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Probable mechanism of hypoglycemic activity of basic acid, a natural product isolated from. Bumelia sartorum
Abstract
Bassic acid, an unsaturated triterpene acid isolated from an ethanol extract of Bumelia sartorum rootbark, elicited significant hypoglycemic activity in alloxan-diabetic rats and altered the pattern of glucose tolerance in these animals. In addition, bassic acid treatment increased significantly the glucose uptake process and glycogen synthesis in isolated rat diaphragm. Bassic acid treatment increased plasma insulin levels significantly in alloxan-diabetic rats. It is suggested that the hypoglycemia activity of bassic acid may be mediated through enhanced secretion of insulin from the pancreatic beta-cells.
... and a member of the Sapotaceae family which is native to Brazil. The phytochemical studies of B.sartorum showed the presence of triterpenoids and steroids such as the (2β,3β,4α)-2,3,23trihydroxyoleana-5,12-dien-28-oic acid and bassic acid, identified as hydrolysis product from the ethanol extract [31,32]. ...
... An unsaturated triterpene acid isolated from an ethanol extract of B.sartorum root bark called bassic acid was found to elicit significant hypoglycemic activity in alloxan-diabetic rats and also increase plasma insulin levels significantly [32], the structure of bassic acid is shown in Figure 2. Bassic acid acts by increasing the glucose uptake and glycogen synthesis in isolated rat diaphragm and elevating plasma insulin levels; the effect appears to be mediated by an insulin secretagogue in pancreatic β cells [32]. Sapogenol a steroid from B.sartorum shows hypoglycemic effect in normal and alloxan-induced hyperglycemic mice [33]. ...
... An unsaturated triterpene acid isolated from an ethanol extract of B.sartorum root bark called bassic acid was found to elicit significant hypoglycemic activity in alloxan-diabetic rats and also increase plasma insulin levels significantly [32], the structure of bassic acid is shown in Figure 2. Bassic acid acts by increasing the glucose uptake and glycogen synthesis in isolated rat diaphragm and elevating plasma insulin levels; the effect appears to be mediated by an insulin secretagogue in pancreatic β cells [32]. Sapogenol a steroid from B.sartorum shows hypoglycemic effect in normal and alloxan-induced hyperglycemic mice [33]. ...
It is projected by the World Health Organization (WHO) that by the year 2030, diabetes will be the leading cause of death in the world judging from the current trend of the disease. Medicinal plants are used in traditional systems all over the world since time immemorial. About 80% of the world population still rely on traditional herbal medicine to meet their primary health care needs especially in rural areas of developing nations.
Scientific studies elucidating the mechanism of action of some traditional medicines have been instrumental in the development of some modern medicines. It is in the light of the above that the present review provides profiles of plants with hypoglycemic properties starting from the discovery of a well-known and acceptable medication for diabetes: metformin. We traced the origin of the discovery of metformin from the plant Galega officinalis (Family: Fabaceae) to the drug form and we have highlighted the various efforts taken for the final product to be arrived at.
Plants discussed in this review include; Anacardium occidentale Linn, Bumelia sartorum Mart, Coccinia indica Wight & Arn, Phaseolus vulgaris L, Vaccinium myrtillus L, Rauwolfia vomitoria Afzel, Panax quinquefolius L, Panax ginseng C.A.Mey, Cinnamomum tamala (Buch.-Ham.).
... Kinsenoside, Azadirachtin, Berberine, and Quercetin extracted from Anoectochilus roxburghii, Azadirachta indica, Berberis aristata, and Boerhavia diffusa, respectively, were reported to induce self-repair of pancreatic β cells by acting as an inhibitor of hepatic tissue enzymes thereby reducing the glycosylated haemoglobin level [95][96][97][98][99][100][101][102][103][104][105][106][107]. Sulforaphane and Basic acid extracted from Brassica juncea and Bumelia sartorum were reported to decrease hepatic gluconeogenesis by nuclear translocation and enhance glucose uptake and glycogen synthesis [108][109][110][111][112]. Cajanin and papain extracted from Cajanus cajan and Carica papaya are well known to enhance glucose uptake, thereby reducing postprandial blood glucose levels [113][114][115][116][117]. Furthermore, Limonene from Cassia auriculata and Carvone from Carum carvi was found to increase the activity of hexokinase in the liver and promote glucosidase inhibitor activity [115][116][117][118][119][120]. ...
... Enhanced insulin secretion, glucose uptake, and glycogen synthesis. [111,112] 13 ...
Background
Diabetes is a chronic metabolic disorder having a global prevalence of nearly doubled over the last 30 years and has become one of the major health concerns worldwide. The number of adults with diabetes increased to 537 million in 2021.
Introduction
The overarching goal of diabetic research and treatment has always been to restore insulin independence and an average blood glucose level. Chemotherapeutic antidiabetic agents can manage diabetes but often show toxicity and drug resistance. Natural phytomedicines may be useful along with stem cell therapy for diabetes management. Even if the whole pancreatic organ and islet transplantation, are becoming benchmark techniques for diabetes management and control, a considerable scarcity of eligible donors of pancreatic tissues and organs severely limits their use. Stem cell treatment provides a bunch of possibilities for treating people with diabetes.
Methods
For this purpose, comprehensive article searching was conducted, with relevant material obtained using search engines such as Scopus, PubMed, MEDLINE, Google, and others, using appropriate keywords.
Results
Stem cell therapies, including induced pluripotent stem cells and mesenchymal stem cells, are now becoming a popular area of investigation. Recent advancements in stem cell therapy might provide a feasible treatment option. Furthermore, in recent years, some novel bioactive compounds derived from plants have demonstrated antidiabetic action with higher potency than oral hypoglycaemic medications. Recent regenerative medicine and stem cell treatment advancements might subsequently provide a feasible diabetic management option. On the other hand, medicinal herbs have been considered a better choice for the extensive treatment of diabetes.
Conclusion
If proper attention is not given to control diabetes by antidiabetic chemotherapeutic agents, natural phytomedicine, and sophisticated treatment like stem cell therapy, then the lifespan of patients will be decreased, and some associated secondary problems will also arise. So, the present review attempts to discuss naturopathy as an alternative resource in combination with stem cell therapy for the progressive management of diabetes and associated disorders.
... The polyherbal formulations might be producing its hypoglycaemic effect by an extra-pancreatic action [12], e.g. possibly by stimulating glucose utilization in peripheral tissues [13,14]. Also, it could be the result of an increase in glycolytic [15] and/or glycogenic enzymes activity in peripheral tissues [13]. ...
... possibly by stimulating glucose utilization in peripheral tissues [13,14]. Also, it could be the result of an increase in glycolytic [15] and/or glycogenic enzymes activity in peripheral tissues [13]. Also it has one more possibility that the polyherbal formulations may decrease the secretion of the counter regulatory hormones (glucagons, cortisols and growth hormones) [16] and thereby decrease the plasma glucose in diabetic patients. ...
Background: The antidiabetic activity of the individual plant parts is well known, but the synergistic or combined effects are unclear. The concept of polyherbalism has been highlighted in Sharangdhar Samhita, an Ayurvedic literature dating back to 1300 AD. Polyherbal formulations enhance the therapeutic action and reduce the concentrations of single herbs, thereby reducing adverse events. The study focuses on polyherbal formulations of five different medicinal plants used for the treatment of Type II diabetic patients.
Methods: In the present study five medicinal plants (Mango, Guava, Amla, Garlic and Onion) with proven antidiabetic and related beneficial effects were selected for the preparation. The efficacy of prepared formulations was tested on Type II diabetic patients and compared with placebo diabetic control patients.
Results: The polyherbal formulations produced a significant decrease in blood glucose level after 8 weeks of treatment. Diabetic patients exhibited increase levels of lipid profiles such as cholesterol, triglycerides, and low density lipoprotein cholesterol (LDL-cholesterol), and a decrease in the level of high density lipoprotein cholesterol (HDL-cholesterol) during the first week of treatment. The elevated lipid profiles were restored to near normal by the treatment of polyherbal formulations for all the estimated parameters at 8th week. In addition, the polyherbal formulations also restored the BMI, blood pressure, haemoglobin, glycosylated
haemoglobin and urinary parameters levels which indicates that they reduce the other complicacies of diabetes. The results of the formulations on Type II diabetic group were strong evidence that not only it restored the glycemic level but also reduced the lipid profile to the near normal.
Conclusion: Based on the findings, the polyherbal formulations have significant antidiabetic potential for Type II diabetic patients
... Other studies showed that S. obtusifolium bark has a hypoglycemic effect in normal and alloxan-induced diabetic rats [7,9] and suggest that bassic acid can be responsible for this hypoglycemic activity [9]. ...
... Other studies showed that S. obtusifolium bark has a hypoglycemic effect in normal and alloxan-induced diabetic rats [7,9] and suggest that bassic acid can be responsible for this hypoglycemic activity [9]. ...
Sideroxylon obtusifolium (Sapotaceae), popularly known as 'quixaba', is used in folk medicine for the treatment of gastritis, ulcer, inflammation and hyperglycemia. The present deals with the determination of antimicrobial action in vitro of S. obtusifolium bark extract. The ethanolic extract and different polarities fractions have been subjected to detect potential antimicrobial activity against Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Candida albicans using a disc diffusion method. The results showed that the S. obtusifolium bark extract and fractions exhibited antimicrobial activity against tested strains, except E. coli.
... acid isolated from an ethanolic extract of Bumelia sartorum root bark produced a hypoglycaemic effect in alloxan-induced diabetic rats (Naik et al., 1991). It increased glucose uptake and glycogen synthesis on isolated rat diaphragm and plasma insulin level (Naik, 1991). ...
... acid isolated from an ethanolic extract of Bumelia sartorum root bark produced a hypoglycaemic effect in alloxan-induced diabetic rats (Naik et al., 1991). It increased glucose uptake and glycogen synthesis on isolated rat diaphragm and plasma insulin level (Naik, 1991). It appears that this effect was mediated by an insulin secretaguogue effect in pancreatic β-cell. ...
The anti-diabetic effect of methanol extract of stem bark of Ceiba pentandra and its beneficial/ toxicological effect on hematological parameters in normal and alloxan-induced-diabetic rats were studied. The acute toxicity (LD 50) test and phytochemical analysis were also carried studied. The diabetic rats were divided into five groups of 5 animals each given oral administration of the extract daily for 14 days. The antidiabetic study was carried out using 200, 400, and 800 mg/kg body weight of C. pentandra extract. The methanol extract of C. pentandra significantly (p < 0.05) reduced the blood glucose level in diabetic and norm glycemic rats in comparison with glibenclamide (standard drug). The effect of C. pentandra at 800 mg/kg (33.6%) was more effective compared to glibenclamide (23.0%) in lowering blood glucose with the added benefit of restoring reduced hematological parameters in diabetic rats to near normal level in norm glycemic rats. The acute toxicity (LD 50) test of the methanol extract was found to be greater than 5000 mg/kg. This showed the extract is relatively safe. The plant is also rich in flavonoids, saponins, resins, terpenoids, glycosides, and tannins. The result of this study shows that C. pentandra does possess anti-diabetic activity, beneficial effect and hence can ameliorate hyperglycemia and anemia in alloxan-induced diabetic rats establishing its potential as a source for isolation of new oral antihyperglycaemic agents.
... acid isolated from an ethanolic extract of Bumelia sartorum root bark produced a hypoglycaemic effect in alloxan-induced diabetic rats (Naik et al., 1991). It increased glucose uptake and glycogen synthesis on isolated rat diaphragm and plasma insulin level (Naik, 1991). ...
... acid isolated from an ethanolic extract of Bumelia sartorum root bark produced a hypoglycaemic effect in alloxan-induced diabetic rats (Naik et al., 1991). It increased glucose uptake and glycogen synthesis on isolated rat diaphragm and plasma insulin level (Naik, 1991). It appears that this effect was mediated by an insulin secretaguogue effect in pancreatic β-cell. ...
... Terpenes are bioactive compounds that occur both as hydrocarbons and terpenoids (oxygen-containing compounds), present naturally in many herbs, and are known to possess significant hypoglycaemic properties [20]. Terpenes show antidiabetic potential by either of the mechanisms that include stimulation of insulin secretion [21][22][23][24], enhanced plasma BER (β-endorphin immunoreactivity) by activation of α1-ARs to improve the discharge of β-endorphin, which has the potential to excite opioid micro-receptors to diminish gluconeogenesis in the liver and boost glucose uptake in the soleus muscle [25,26], α-glucosidase inhibition [27][28][29], increasing glucose uptake and glycogen synthesis and blood insulin concentrations. It appears that the reason for this outcome was the facilitation of insulin secretagogue impact in β-cells of the pancreas [30] by appreciably augmenting the blood pyruvate concentration and liver glycogen level [31] by improving insulin discharge from β-cells of the pancreas, which is due to improved stimulation of β-cells and insulin synthesis [32][33][34], and by enhancing glucose utilization in striated muscles, which leads to lower plasma glucose levels and increases in insulin discharge from pancreatic β-cells [24,28,35,36]. ...
The hypoglycaemic and hypolipidemic potential of ethanol extract of C. bursa-pastoris (ECbp) in streptozotocin (STZ)-provoked diabetic rats was evaluated, and compounds with their α-amylase and α-glucosidase inhibitory potential were isolated. Acute oral toxicity was evaluated in rats. Streptozotocin (STZ) (50 mg/kg body weight) was injected intraperitoneally into rats for diabetes induction. In diabetic rats, ECbp (0.2 g/kg b.w, p.o.) was administered orally for 21 days, and its outcome on blood glucose levels and body weight was observed on a weekly basis besides lipid profile. Compound isolation from ECbp was performed using column chromatography. Oral feeding of ECbp did not produce any toxic effects or death at a dose of 2,000 mg/kg body weight. A serum glucose reduction trend was observed in rats fed with glucose pre-treated with 200 mg/kg b.w. ECbp also appreciably (p < 0.001, p < 0.01, and p < 0.05) diminished raised blood glucose with decreased blood cholesterol levels and led to increased serum high-density lipoprotein levels in comparison to diabetic control rats. Body weight levels were considerably higher (p < 0.05) in diabetic rats treated with ECbp than in diabetic control rats. Isolation of two terpene derivatives (ECbp-1 and ECbp-2) was performed using ECbp, which exhibits significant α-amylase and α-glucosidase inhibition.
... Therefore, carvone of aqueous extract of A. graveolens is responsible for its antidiabetic activity. Mobasseri et al. (2014) conducted a randomized, double-blind, placebo-controlled study to assess the effect of A. graveolens supplementation on insulin sensitivity in type-2 diabetic patients [29]. Fresh leaves and stems of the plant were collected, dried, and powdered, and tablets containing 1.1 gm of A. graveolens were prepared. ...
Apiaceae is one of the biggest and most important plant families, comprising about
3700 species and 434 genera. Most of them are aromatic, flowering plants. The plants in this
family are beneficial for everyday use and treating diseases. They are a rich source of nutraceuti�cals and secondary metabolites attributed to different pharmacological activities. Some plants un�der this family possess antidiabetic activity through different mechanisms, such as inhibiting car�bohydrate hydrolyzing enzymes, stimulating insulin secretion, and regulating glucose transport�ers. Diabetes mellitus has become a chronic metabolic disorder whose management is of utmost
importance in recent days. The present review aims to establish the use of Apiaceae family plants
in treating diabetes mellitus. The availability of plants, their bio-constituents, mode of action, and
experimental studies have also been briefly described here.
... Furthermore, the hyperglycemic effect of flavonoids can be mediated through an increase in hepatic glucose storage by stimulating the action of glycolytic and glycogenic enzymes or by inhibiting glucose-6-phosphatase. This consequently results in the uptake of glucose into cells and the reduction in the blood glucose level through the up-regulation of glycogen formation, down-regulation of the rate of glycogen breakdown, and glucose synthesis (Naik et al., 1999;Waltner et al., 2002;Srkhail et al., 2007). ...
Polyphenolic phytochemicals of Cola nitida, with their potential therapeutic ability can modulate metabolic and transcriptional expression of proteins and enzymatic activities that culminate to hyperglyceamic effects. This study investigated the hyperglyceamic effects of polyphenolic phytochemical extracts of Cola nitida in Wistar rat in-vivo and established a parallel inhibition of the enzymes (α-amylase and α-glucosidase) in their activities as the concentration increased. On administration of the extracts, the activity of α-amylase was inhibited from control, 32 ± 0.00 to 16 ± 0.02u/L as the concentration increased. Also, the activity of α- glucosidase was inhibited from 17 ± 0.01 to 10 ± 0.00u/L in relation to the concentration of the extracts. The inhibitory effect of Cola nitida on carbohydrate hydrolyzing enzymes delayed glucose utilization resulting to elevated glucose concentration from 6.07 ± 0.02 to 9.11 ± 0.01 mMol/L. The composition of the polyphenolic phytochemicals in the Cola nitida analyzed with gas chromatographic techniques was found to contain; apigenin, 6.0 ± 0.01; catechin, 7.1± 0.01; epicatechin, 4.8 ± 0.02; narigenin, 4.9 ± 0.10 mg/100mg and these are the active ingredients of the bioactive compounds that are responsible for the hyperglyceamic effects of Cola nitida.
... The reduced blood glucose level and improved antioxidant activity reported by some authors through administration of safranal intraperitoneally in the diabetic rat in a dose-dependent manner [93]. Anti-hyperglycaemic activity of terpene compounds An unsaturated triterpene presents in the root and bark of Bumelia sartorum isolated from its ethanolic extraction shows hypoglycaemic action by increased insulin production from β-cells [94]. A clinical trial on Momordica charantia reported anti-hyperglycemic activity [95]. ...
Abstract
Background: Diabetes mellitus (DM) is a growing disease across the world; diabetes is a complex metabolic disorder
in which blood glucose concentration level increases and continue for a prolonged period due to a decrease secretion of insulin or action, resulting in the disorder of carbohydrate, lipid, and protein metabolism. The plant-related
bioactive compounds have proven their efcacy with least toxicities and can be utilized for the disease treatment. Our
objective is to elucidate the mechanism of action of plant bioactive compounds which can give future direction in
diabetes treatment.
Main body: In this review paper, we briefy study more than 200 research papers related to disease and bioactive
compounds that have therapeutic applicability in treatment. The plant contains many bio-active compounds which
possess in vitro and in vivo anti-diabetic efect which may be responsible for the hypoglycaemic property by inhibiting the digestive enzyme i.e. alpha-amylase and alpha-glucosidase, by producing mimetic action of insulin, by reducing the oxidative stress, by showing antihyperglycemic activity and hypolipidemic activity, by inhibition of aldose
reductase, and by increasing or enhancing glucose uptake and insulin secretion.
Conclusion: Our study revealed that terpenes, tannin, favonoids, saponin, and alkaloids are important bioactive constituents for anti-diabetic activity. The mechanistic approach on alpha-glucosidase and alpha-amylase, hypolipidemic
activity, and AR inhibitory action clear-cut explain the therapeutic applicability of these bioactive compounds in
disease. Plants that contain these bioactive compounds can be good drug candidates for future research on diabetes
treatment
... Our findings showed that TRDI was a potent insulin mimic in skeletal muscle and lowered blood glucose levels ( Figure 6A). Bassic acid, an unsaturated triterpene isolated from an ethanol extract of Bumelia sartorum root bark, increased hypoglycemic action by increasing insulin release from pancreatic cells [51]. Additionally, TRDI (G4 group) increased GLUT4 expression and glycogen levels in the skeletal muscle in diabetic mice. ...
Insulin resistance (IR) plays a key role in the pathogenesis and clinical outcome of patients with multiple diseases and diabetes. In this study, we examined the antidiabetic effects of a terpenoid-rich extract from Dillenia indica L. bark (TRDI) in palmitic acid-induced insulin resistance (PA-IR) in C2C12 myotube and a streptozotocin (STZ)-induced diabetic mice model and explored the possible underlying mechanism. TRDI showed potential DPPH- and ABTS-radical scavenging effects with a half-maximal inhibitory concentration (IC50) value of 9.76 ± 0.50 µg/mL and 17.47 ± 1.31 µg/mL, respectively. Furthermore, TRDI strongly mitigated α-glucosidase activity with an IC50 value of 3.03 ± 1.01 µg/mL, which was 92-fold higher than the positive control, acarbose (IC50 = 279.49 ± µg/mL). TRDI stimulated the insulin receptor substrarte-1 (INS-1), downregulated phosphoinositide-dependent kinase-1 (PDK1) and protein kinase B (Akt) in both normal and PA-IR C2C12 cells as well as in STZ-induced diabetic mice, enhanced glucose transporter 4 (GLUT4) translocation to the plasma membrane (PM), and increased glucose absorption. Furthermore, TRDI administration significantly reduced PA-induced reactive oxygen species (ROS) formation in C2C12 cells and increased the protein level of numerous antioxidant enzymes such as superoxide dismutase 1 (SOD1), catalase (CAT), glutathione peroxidase-1 (GPx-1) and thioredoxin reductase (TrxR) both in vitro and in vivo. Furthermore, TRDI facilitated nuclear factor erythroid 2 related factor 2 (Nrf2) nuclear translocation and increased HO-1 expression in PA-IR C2C12 cells and STZ-induced diabetic mice. However, for the inhibition of Nrf2, TRDI failed to resist the effects of IR. Thus, this study provides new evidence to support the use of TRDI for diabetes treatment.
... It has been suggested that bassic acid increases insulin secretion from pancreatic beta-cells. This could be the underlying mechanism by which bassic acid shows its hypoglycemic property which was found to be approximately equal to that of chlorpropamide (42). ...
Diabetes, a chronic physiological dysfunction affecting people of different age groups and severely impairs the harmony of peoples’ normal life worldwide. Despite the availability of insulin preparations and several synthetic oral antidiabetic drugs, there is a crucial need for the discovery and development of novel antidiabetic drugs because of the development of resistance and side effects of those drugs in long-term use. On the contrary, plants or herbal sources are getting popular day by day to the scientists, researchers, and pharmaceutical companies all over the world to search for potential bioactive compound(s) for the discovery and development of targeted novel antidiabetic drugs that may control diabetes with the least unwanted effects of conventional antidiabetic drugs. In this review, we have presented the prospective candidates comprised of either isolated phytochemical(s) and/or extract(s) containing bioactive phytoconstituents which have been reported in several in vitro, in vivo, and clinical studies possessing noteworthy antidiabetic potential. The mode of actions, attributed to antidiabetic activities of the reported phytochemicals and/or plant extracts have also been described to focus on the prospective phytochemicals and phytosources for further studies in the discovery and development of novel antidiabetic therapeutics.
... Triterpenoid saponins from Primula denticulate were reported to potentially possess glucose-lowering properties in STZ-induced diabetic rats [25]. Bassic acid, an unsaturated triterpene acid, was reported to increase glucose absorption and glycogen synthesis and increase plasma insulin levels in alloxan-diabetic rats [26]. Hence, the novel compounds could possess insulin-mimetic activity. ...
Here, we identified the mechanisms of action of antidiabetic activity of novel compounds isolated from Cassia fistula stem bark in STZ-diabetic animals. Novel triterpenoid compounds (C1, C2 and C3) were treated to STZ-administered diabetic animals at a concentration of 20mg/kg body weight orally for 60 days to assess their effects on plasma glucose, plasma insulin/C-peptide, serum lipid markers and the enzymes of carbohydrate metabolism, glucose oxidation and insulin signaling molecules. Oral administration of novel triterpenoid compounds to STZ-diabetic animals significantly decreased (p < 0.05) the plasma glucose concentration on the 7th, 15th, 30th, 45th and 60th daysin a duration-dependent manner (p < 0.05). Plasma insulin (p < 0.0001)/C-peptide (p < 0.0006), tissue glycogen (p < 0.0034), glycogen phosphorylase (p < 0.005), glucose 6-phosphatase (p < 0.0001) and lipid markers were significantly increased (p < 0.0001) in diabetic rats, whereas glucokinase (p < 0.0047), glycogen synthase (p < 0.003), glucose oxidation (p < 0.001), GLUT4 mRNA (p < 0.0463), GLUT4 protein (p < 0.0475) and the insulin-signaling molecules IR mRNA (p < 0.0195), IR protein (p < 0.0001), IRS-1 mRNA (p < 0.0478), p-IRS-1Tyr612 (p < 0.0185), Akt mRNA (p < 0.0394), p–AktSer473 (p < 0.0162), GLUT4 mRNA (p < 0.0463) and GLUT4 (p < 0.0475) were decreased in the gastrocnemius muscle. In silico analysis of C1–C3 with IRK and PPAR-γ protein coincided with in vivo findings. C1–C3 possessed promising antidiabetic activity by regulating insulin signaling mechanisms and carbohydrate metabolic enzymes.
... The experiment was repeated using 0.2, 0.4 and 1.0 g/kg body weight of the extract. When testing 0.4 g/kg body weight, a third group of 12 rabbits was included which was given 0.1 g/kg body weight chlorpropamide (Naik et al., 1991). ...
An aqueous extract of Securinega virosa is used by traditional healers in Tanga (northeastern Tanzania) as an aphrodisiac and in the treatment of impotence, which is one of the manifestations of diabetes mellitus. An aqueous extract of the roots at doses of 0.1,0.2, 0.4 and 1.0 g/kg body weight lowered the area under the oral glucose tolerance curve (OGTT) in normal albino rabbits by 0.3 (P >0.05), 7.85, 11.0 and 9.6% (P =0.05), respectively. Chlorpropamide (0.1 g/kg body weight) had a greater effect on blood glucose and lowered area under the OGTT curve by 16.3%. The extract, at a dose of 0.4 g/kg body weight, had no effect on fasting blood glucose (FBG) when compared to controls given distilled water (P >0.05), except at 4 h, when the FBG for treated animals was higher. The LD 50 (95% confidence interval) determined by intraperitoneal administration of the extract to white albino mice was 0.30 (0.20–0.50) g/kg body weight. We conclude that the aqueous extract of Securinega virosa roots lowered the area under the OGTT curve dose-dependently at doses between 0.1 and 1.0 g/kg body weight. It did not lower blood glucose below fasting levels both in the fed and fasted state. More work is required to determine the toxic characteristics of the extract and the utility of the observed activity in the management of diabetes mellitus in humans.
... (syn. Bumelia sartorum), in diabetic rats through enhanced secretion of insulin (Naik et al. 1991). The cumulative publication and citation counts grew steadily in the 2000s and had a much sharper increase in the 2010s (Figure 1). ...
The current study aimed to identify which natural products and which research directions are related to the major contributors to academic journals for diabetes therapy. Bibliometric data were extracted from the Web of Science online database using the search string TOPIC = (‘‘natural product*’ OR ‘‘natural compound*’ OR ‘‘natural molecule*’ OR ‘phytochemical*’ OR ‘‘secondary metabolite*’) AND TS = (‘diabet*’) and analysed by a bibliometric software, VOSviewer. The search yielded 3694 publications, which were collectively cited 80,791 times, with an H-index of 117 and 21.9 citations per publication on average. The top-contributing countries were India, the USA, China, South Korea and Brazil. Curcumin, flavanone, resveratrol, carotenoid, polyphenols, flavonol, flavone and berberine were the most frequently cited natural products or compound classes. Our results provide a brief overview of the major directions of natural product research in diabetes up to now and hint on promising avenues for future research.
... Sesquiterpene 3hydroxycacalolide isolated from Psacalium decompositum has shown anti-hyperglycemic activity (Inman et al. 1999). An unsaturated triterpene, bassic acid isolated from an ethanol extract of Bumelia sartorum root bark stimulated the hypoglycemic activity, mediated through enhanced secretion of insulin from the pancreatic β -cells (Naik et al. 1991). TransDehydrocrotonin (tDCTN: a 19norclerodane diterpene isolated from the bark of Croton cajucara) have shown a hypoglycemic effect equivalent to glibenclamide in alloxaninduced diabetic rats (Farias et al. 1997). ...
Type II diabetes is a metabolic disorder characterized by hyperglycemia arising from defective insulin signaling. Several synthetic drugs are being used for diabetes treatment, but they have adverse effects. So as an alternative approach, compounds from plants with lesser/no side effects and comparatively cheaper are gaining momentum. Terpenes comprise a class of diversified phytochemicals, which have beneficial effects and important functions in plants. They have shown a series of biological properties that healthpromoting conduct in humans. Besides, a lot of terpenes have also been reported to be much less toxic as compared to synthetic compounds. Diabetic people could be benefited from terpenes obtained either from the diet or from plant-derived herbal medicines. Due to the natural origin of terpenes, they are supposed to be a safe and promising agent in eliminating the causes and effects of diabetes. This paper reviews the research reports of terpenes as their antidiabetic potential, mechanistic action, preclinical profile, shortcomings, and prospect in the effective management of diabetes.
... Moreover, flavonoids have their effect either by promoting glucose entry into cells, thereby stimulating glycolytic enzymes and glycogenic enzymes [12] or by inhibiting glucose-6-phosphatein the liver, consequently reducing the release of glucose in the blood. Increased insulin levels could be due to the stimulatory effect of rutin, thereby potentiating the existing β-cells of the islets of Langerhans in diabetic rats [13]. In addition, the aglycone of rutin, i.e., quercetin, is reported to encourage the pancreatic islets to regenerates [14]. ...
Objective: Cyperus squarrosus, belongs to the family Cyperaceae, has been claimed to possess antidiabetic activity in the ethnomedicinal literature in India. Therefore, the present study was to investigate the effects of aqueous and ethanolic extracts of C. squarrosus (EECS) on diabetes and its cardiovascular complications with streptozotocin-induced diabetes in rats. Methods: Wister albino rats of either sex were made diabetic with streptozotocin (65 mg/kg, i.v.). Glibenclamide (5 mg/kg) was taken as standard drug. Treatment of aqueous and EECS (aqueous extract of C. squarrosus and EECS) was given in the dose of 200 and 400 mg/kg/day, p.o for 8 weeks and biochemical (serum glucose, cholesterol, triglycerides, and high-density lipoprotein [HDL]) parameters were recorded. Results: Streptozotocin-treated group produced significant increased levels of serum glucose, cholesterol, triglycerides, HDL, creatine kinase-myocardial band (CK-MB), and lactate dehydrogenase (LDH) levels and all these changes were prevented by the treatment with aqueous and EECS in both doses. Conclusion: As compare with ethanolic extract treated group, aqueous extract treated group exhibits significant (p<0.001) effect on CK-MB and LDH levels. Our result suggests that aqueous and EECS prevents the streptozotocin-induced metabolic abnormalities as well as cardiovascular complications.
... These data showed that eurocristatine treatments can help to alleviate the diabetic symptoms of FBG reduction. This result further proves that eurocristatine, as a natural product, [29][30][31] has the advantages of being nontoxic and efficient in lowering blood sugar. ...
Fuzhuan brick tea (FBT) is a Chinese dark tea that is famous for its significant health benefits, in which Eurotium cristatum (E. cristatum) strains play a vital role in its postfermentation process. In this study, eurocristatine with hypoglycemic activity was discovered for the first time and purified from the spores of E. cristatum growing in FBT. Eurocristatine (98%) was obtained by D-101 macroporous resin-based column chromatography and preparative high performance liquid chromatography (HPLC) with a C18 column as the stationary phase and 35% acetonitrile in ultrapure water as the mobile phase. Hypoglycemic activity in a Hep-G2 cell hypoglycemic model was used as a screening indicator during purification. The chemical structure of eurocristatine was characterized by ESI/MS, ¹H NMR and ¹³C NMR analyses. The antidiabetic effects of eurocristatine were verified in high-fat diet/streptozocin-induced type 2 diabetes mellitus (T2DM) rats. The results showed that eurocristatine significantly reduced fasting blood glucose. Our study demonstrated that eurocristatine, as a newly discovered hypoglycemic active substance, could be considered a potential candidate for the treatment of diabetes and its complications.
... The polyherbal formulations might be involve an extrapancreatic action and produce hypoglycemic effect, [2] for example, possibly by stimulating glucose utilization in peripheral tissues. [35,36] Sustained reduction in hyperglycemia may decrease the risk of developing microvascular complications and most likely reduce the risk of macrovascular complications. [37] Table 1 showed the levels of plasma glucose and insulin in control and experimental animals. ...
... Atractans A [134] Galactomannan gum [135] Terpenoids and steroids α-amyrin acetate [136] Bassic acid [137] Escins-IIA and IIB [138] Ginsenosides [139,140] Momordin [141] β-sitosterol, γ-sitosterol [142,143] stigmasterol [144] Forskolin [145] Saponins Isothiocyanate Prototinosaponins, pseudoprototinosaponin Sulforaphane [115] [57] ...
Background:
Over the past decades, the development and use of an array of prescription medications has considerably improved the clinical management of type 2 diabetes mellitus and the quality of life of patients. However, as our knowledge of the associated risk factors and approaches to its management increases, the increasing roles of diet and the composition of the diet in the aetiology and successful management of diabetes mellitus are being illuminated. Presently, a lot of attention is being given to nutraceuticals and certain phytochemicals that are integral parts of the human diet. It is believed that a clearer understanding of their roles may be crucial to 'non-invasive' or minimally-intrusive management, with regards to daily living of patients. In this review, an overview of nutraceutical components and phytochemicals that may be of benefit, or had been known to be beneficial in diabetes mellitus is given. Also, how the roles of such dietary components are evolving in the management of this disorder is highlighted. Lastly, the obstacles that need to be overcome before nutraceuticals can be considered as options for the clinical management of diabetes mellitus is considered.
Conclusion:
Despite studies that demonstrate their efficacy, no nutraceutical or food-derived compound has been formally adopted as a direct replacement for any class of antidiabetic drugs.
... Previous research on Ajuga species suggested that the hypoglycemic effect of Ajuga iva extract occurs without stimulating insulin secretion [14,32]. Possible mechanism has been proposed to be insulin mimetic effect on muscle and adipose tissues by stimulating glucose uptake and metabolism [33], insulin-like action or inhibitory effect on the hormones that increase the blood glucose levels [14,34]. Chemical studies on Ajuga species have revealed the presence of several flavonoids, tannins, terpenes, steroids and phytoecdysteroids [35]. ...
Background and objective: Ajuga species (Lamiaceae) are traditionally used in the treatment of jaundice, joint pain, sciatic nerve, and diabetes in different countries. The aim of this study was to investigate the antioxidant and hypoglycemic activities and safety of Ajuga chamaecistus ssp. tomentella. Methods: Antioxidant activity, radical scavenging effect, and total phenolics content of the aqueous and methanol extracts were assessed using ferric reducing antioxidant power (FRAP), 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging and Folin-Ciocalteu methods. Streptozotocin (STZ) induced diabetic mice were studied in separate groups comprising aqueous and methanol extracts (200, 400, 800 mg/kg), metformin (500 mg/kg) and a negative control group. Results: The n-butanol fraction showed the most phenolics content (26.5 mg GAE/g of extract) and the highest antioxidant power)346.7 mmol FeІІ/g of extract) as well as the most considerable radical scavenging activity (IC 50 =15.34 µg/mL). In STZ-diabetic mice, repeated oral administration of all doses of extracts showed a significant decrease in plasma glucose levels after 3, 14 and 28 days. The results of acute toxicity study showed that the ethanol extract was non-toxic up to the dose of 6000 mg/kg. Based on the sub-chronic toxicity results, a significant decrease in cholesterol and triglyceride was observed after using the extract (1000 mg/kg) for 23 rd and 45 th days. Histopathology of animal tissues revealed no significant differences in animal tissues between treated and control groups after 23 and 45 days. Conclusion: our study indicated the antioxidant potential, safety and hypoglycemic effect of A. chamaecistus ssp. tomentella extracts.
... In addition, it significantly increased the process of glucose uptake and glycogen synthesis in the isolated rat diaphragm. Bassic acid also increases insulin secretion from pancreatic beta cells [30]. ...
... In addition, it significantly increased the process of glucose uptake and glycogen synthesis in the isolated rat diaphragm. Bassic acid also increases insulin secretion from pancreatic beta cells [30]. ...
Diabetes mellitus is a common and widespread disease that affects citizens in developed and developing countries. Diabetes is a disease that combines inherited and environmental causes that cause high blood sugar levels known as hyperglycemia.Phytotherapy has achieved good clinical practice and shows a bright future in the treatment of diabetes mellitus. The purpose of this review was to provide information about the most useful antidiabetic compounds from plants available through numerous literature sources from various databases. Many researches confirmed the benefits of phytoconstituantswith antidiabetic effects in the management of diabetes mellitus. Thus, drugs from plants may control all pathological aspects of diabetes, either by increasing insulin production by the pancreas, helping to lower the body's insulin requirements, or reducing gluconeogenesis in the liver. The effect of these antidiabetic plants has been tested in vivo and in vitro on rats, mice, rabbits and dogs.Very few have been tested on humans for their effectiveness.
... In addition, high carbohydrate diet has been employed for experimental animal to maintain the good diabetic model. Adrenaline is responsible for hyperglycemia in an animal model, and high carbohydrate diet plays a synergistic role for maintaining diabetes [8,9]. The diabetic rabbits with FPG level 200-250 mg/dl were divided into different groups of six animals each in the following manner. ...
Objective: As per the ethnopharmacological information has Butea monosperma been used to treat diabetes mellitus by the tribal people of tropical and subtropical areas. However, there is no much more scientific report available about the antidiabetic property of the leaves of the plant. Hence, the study was undertaken to evaluate the antidiabetic effect of ethanolic extract of B. monosperma on blood levels of adrenaline-induced and glucose feed diabetic rabbits.Methods: The three different doses of the extracts (100, 200, and 400 mg/kg) were administered orally to an experimental animal. The animals were induced diabetics by adrenaline and high glucose diet. Blood glucose level was measured accordingly. For antidiabetic activity, photocolorimeter was used to monitoring the blood glucose level with crest kit box (GOP-POD method).Results: The extracts showed considerable dose-dependent activity. However, the dose 400 mg/kg showed considerable lower of blood glucose level. p<0.01 indicates the significance result. 8 hrs reading 182.5±3.83 for 400 mg does is most effective for reducing blood sugar.Conclusion: The study indicates that the ethanolic extract of B. monosperma leaves possesses antidiabetic properties which suggest the presence of biologically active components.
... alatus) and many others. They possess the capacity to reduce hyperglycemia by promoting glucose uptake and glycogen synthesis [278][279][280]. Dieckol, a compound isolated from E. cava, too exhibits antidiabetic properties by inhibiting -glucosidase and -amylase as with acarbose, a pharmaceutical antidiabetic [281]. ...
Background:
Diabetes has turned into a pandemic disorder that is affecting millions of people worldwide. Industries are aggressively racing and pursuing research towards the discovery of antidiabetic drug and the current global sale of such drugs are ever on the increase. However, in spite of such massive level and expenditure thereof, WHO projects that by 2030, diabetes will rank as the 7th leading cause of mortality.
Objective:
It is in this context that we have reviewed here the various approaches available and possible towards diabetes management. This review also includes the WHO guidelines for controlling the glycemic levels, which must be known and followed by clinicians for a better diabetes management.
Conclusion:
Despite having a wealth of FDA-approved therapeutic options for type 2 diabetes majorities of the patients are not able to achieve the appropriate glycemic control due to various factors. The development of new options with actions at multiple foci of diabetic manifestation and better efficacy may potentially help in improving the current scenario of T2D management.
... Glabridin constituted the major flavonoid in the licorice root extract. The flavonoid exert its hypoglycemic effect by either promoting the entry of glucose into cells, stimulation of glycolytic enzymes and glycogenic enzymes, depression of gluconeogenic enzymes or inhibiting the glucose-6-phosphatase in the liver, subsequently reducing the release of glucose in the blood 30 . These modulatory effects of glabridin on the previous parameters were dose dependent. ...
Glabridin (component of Licorice), a major flavonoid of Glycyrrhiza glabra L. (Fabaceae), is commonly used in the treatment of cardiovascular and central nervous system diseases. Also, it has been associated with a wide range of biological properties such as antioxidant, anti-inflammatory, estrogenic and anti-osteoporotic. Here, we investigated the antidiabetic effects of oral treatment with glabridin on streptozotocin (STZ)-induced diabetic rats. Type 1 diabetes was induced in male albino rats by a single intraperitoneal injection of STZ (60 mg/kg body weight). Diabetes appeared after 1-3 days after STZ injection. The animals were randomly divided into6 groups (7 animals each) as follows; Group 1: Normal control group (negative control group); Group 2 & 3: glabridin-treated control groups (25&50 mg/kg body weight); Group 4:STZ diabetic group (positive control group); Group 5 & 6:glabridin treated diabetic groups(25&50 mg/kg body weight). In normal rats, no harmful effects were detected after orally administration of both doses of glabridin on all parameters measured.The antidiabetic activity of glabridin (especially high dose) was mediated through significantly increased the body weight gain, enzymic/non-enzymic antioxidants and HDL-cholesterol, and significantly decreased relative organ weights, serum glucose, lipid profiles, lipid peroxidation (LPO), pro-inflammatory cytokine, liver and kidney functions. The present study indicated that the anti-inflammatory/anti-oxidant activity of glabridin (especially high dose) may have beneficial effects against complications shown in STZ diabetic rats. © 2016, National Institute of Science Communication and Information Resources (NISCAIR). All Rights Reserved.
... Bumelia sartorum root bark contains bassic acid, an unsaturated triterpene acid showed significant hypoglycemic activity altered glucose tolerance, increased significantly the glucose uptake process and glycogen synthesis in isolated rat diaphragm, increased plasma insulin levels mediated through enhanced secretion of insulin from the pancreatic beta-cells significantly in alloxan-diabetic rats ( Table 1 & Fig. 3) [76]. ...
Diabetes is a major chronic metabolic disorder globally and around of 285 million people are affected by the disease and the number is expected to double in the next two decades. The major focus of anti-diabetic therapies is to enhance insulin production, sensitivity and/or reduce the blood glucose level. Although several synthetic drugs have been developed as antidiabetic agents but their utility has been hampered due to their side effects and poor efficacy. In this scenario, research on natural products has been gained importance due their safety profile in toxicity studies. Terpenoids belong to an important class of natural products and several terpenoids have been reported as antidiabetic agents. Some of them are under various stages of pre-clinical and clinical evaluation to develop them as antidiabetic agents. These agents can inhibit enzymes responsible for the development of insulin resistance, normalization of plasma glucose and insulin levels and glucose metabolism. Triterpenes can act as promising agents in the treatment of diabetic retinopathy, neuropathy and nephropathy or in impaired wound healing by inhibiting several pathways involved in the diabetes and associated complications. However, efforts in understanding the biological actions and clinical studies involving the applications of triterpenes in treating diabetes are very limited. Hence, special attention is imperative to explore the therapeutic potential of these compounds and provide new information to the scientific community. This review aims tp provide the recent advances in triterpenes chemistry, its derivatives, biological interventions and its therapeutic applications with special emphasis on diabetes and its associated disorders.
... Bumelia sartorum root bark contains bassic acid, an unsaturated triterpene acid showed significant hypoglycemic activity altered glucose tolerance, increased significantly the glucose uptake process and glycogen synthesis in isolated rat diaphragm, increased plasma insulin levels mediated through enhanced secretion of insulin from the pancreatic beta-cells significantly in alloxan-diabetic rats ( Table 1 & Fig. 3) [76]. ...
Diabetes is a major chronic metabolic disorder globally and around of 285 million people are affected by the disease and the number is expected to double in the next two decades. The major focus of anti-diabetic therapies is to enhance insulin production, sensitivity and/or reduce the blood glucose level. Although several synthetic drugs have been developed as antidiabetic agents but their utility has been hampered due to their side effects and poor efficacy. In this scenario, research on natural products has been gained importance due their safety profile in toxicity studies. Terpenoids belong to an important class of natural products and several terpenoids have been reported as antidiabetic agents. Some of them are under various stages of pre-clinical and clinical evaluation to develop them as antidiabetic agents. These agents can inhibit enzymes responsible for the development of insulin resistance, normalization of plasma glucose and insulin levels and glucose metabolism. Triterpenes can act as promising agents in the treatment of diabetic retinopathy, neuropathy and nephropathy or in impaired wound healing by inhibiting several pathways involved in the diabetes and associated complications. However, efforts in understanding the biological actions and clinical studies involving the applications of triterpenes in treating diabetes are very limited. Hence, special attention is imperative to explore the therapeutic potential of these compounds and provide new information to the scientific community. This review aims tp provide the recent advances in triterpenes chemistry, its derivatives, biological interventions and its therapeutic applications with special emphasis on diabetes and its associated disorders.
... Based on the data obtained, it was shown that aqueous and ethanolic G. procumbens extracts possess the ability to regulate blood glucose level in Type 1 diabetic rats, which concurs with other reports 16,21,[29][30][31][32] . A parallel study demonstrated that administration of G. procumbens leaves aqueous and ethanolic extracts significantly lowered blood glucose and HbA1c levels as well as increased liver glycogen content and activities of enzymes involved in carbohydrate metabolism without affecting plasma insulin levels in diabetic rats 33 . It has been suggested that instead of acting as an insulinotropic agent, G. procumbens leaves extracts elicit their effects through extrapancreatic pathways, where these extracts might contain chemical compounds such as kaempferol-3-O-glycoside and other glycoside flavonoids 34 that mimic the action of insulin or act by enhancing the effects of insulin at cellular level 29,31 . ...
Diabetes mellitus have been shown to bring about deteriorating effects on the male reproductive system due to increased oxidative stress. Gynura procumbens, an herb with known anti-diabetic properties, was used in this investigation to determine the effect of its aqueous and ethanolic extracts on sperm quality and testosterone level of male streptozotocin-induced Type 1 diabetic rats. Metformin and glibenclamide were used as control drugs in this study. Diabetic rats force-fed with 150 mg/kg of ethanolic G. procumbens extract showed dramatic increase in sperm count (206.89%) and motility as well as testosterone level (16.71%), along with decrease in fasting blood glucose level (38.71%) and sperm mortality (57.62%) when compared to the controls. Treatment with aqueous G. procumbens extract showed similar results with 23.38% and 31.14% decrease in blood glucose level and sperm mortality respectively, coupled with improvement in testosterone level (8.60%), sperm count (124.79%) and motility. The present data indicate that traditional use of G. procumbens as an anti-hyperglycemic agent is justified and may be beneficial for male diabetic patients that suffer from sexual dysfunction as a side effect of prolonged hyperglycemia seen in Type 1 diabetic patients. © 2016, International Journal of Pharmacognosy and Phytochemical Research. All rights reserved.
... The plasma glucose lowering effect in the absence of significant change in plasma insulin concentration (Table 1), suggests that AI treatment may involve an insulin independent mechanism (Dabis et al., 1984), like some species either in the same family (Labiatae) (Jimenz et al., 1986), or in others (Jouad et al., 2000;Benwahhoud et al., 2001). Also, it can act by enhancing glucose utilisation in the peripheral tissues (Naik et al., 1991;Obatomi et al., 1994;Peungvicha et al., 1998). ...
The purpose of this study was to examine the hypoglycaemic effect of the lyophilised aqueous extract of the whole plant of Ajuga iva (L.) Schreber (Labiatae) in normal and streptozotocin-induced diabetic rats. Single and repeated oral administration of the extract of Ajuga iva L (Al) at a dose of 10 mg/kg produced a slight and significant decrease in plasma glucose levels in normal rats 6 h after administration and after 3 weeks of treatment. Al reduced plasma glucose levels of streptozotocin diabetic rats from 337 +/- 9.3 to 102.2 +/- 17.7 mg/dl after 6 h of oral administration (P < 0.001). Repeated oral administration of Al to streptozotocin diabetic rats significantly decreased the plasma glucose levels after I week of treatment (112 +/- 14.4 mg/dl at 1 week vs 337 +/- 9.3 mg/dl at the baseline values, (P < 0.00 1). It continuously decreased thereafter and showed a rapid normalisation after I week of Al treatment. It is concluded that these results demonstrated that the water extract of the whole plant of Al possess a strong hypoglycaemic effect in diabetic rats, and support therefore. its traditional use in diabetes mellitus control. (C) 2002 Published by Elsevier Science Ireland Ltd.
... The flavonoids are group of compounds possessing potential antioxidant properties that may protect pancreatic islets and help in regeneration of βcells which in turn may lead to increase in insulin levels. In addition, flavonoids exert their effect either by promoting the entry of glucose into cells, thus stimulating glycolytic enzymes and glycogenic enzymes [16] or by inhibiting the glucose6phosphatase in the liver, consequently reducing the release of glucose in the blood [17]. Rutin is a flavonol type of flavonoid present in about 3.14% in AQTP. ...
Tephrosia purpurea has been reported to possess antidiabetic activity, however, its effects on cardiovascular complications and cataract associated with diabetes have not been studied. The objective of the present study was to investigate the effects of aqueous extract of Tephrosia purpurea on cardiovascular complications and cataract associated with streptozotocin-induced diabetes in rats. Sprague Dawley rats of either sex were made diabetic with streptozotocin (45 mg/kg, i.v.). Treatment of aqueous extract of Tephrosia purpurea was given in the dose of 300 and 500 mg/kg/day, p.o for 8 weeks. Various hemodynamic (blood pressure, heart rate, +dp/dt, -dp/dt) and biochemical (serum glucose, cholesterol, triglycerides, creatinine, urea, lactate dehydrogenase and creatinine kinase) parameters were recorded after 8 weeks of the treatment. To evaluate cataract, various biochemical estimations were done in eye lens. Streptozotocin produced hyperglycemia; hypoinsulinemia; hyperlipidemia; increased blood pressure; increased creatinine, cardiac enzymes, reduction in heart rate and cardiac hypertrophy in rats and all these changes were prevented by the treatment with aqueous extract of Tephrosia purpurea in both the doses. Streptozotocin also produced decrease in soluble protein and reduced glutathione in lens of rats that was prevented by aqueous extract of Tephrosia purpurea. Our data suggest that aqueous extract of Tephrosia purpurea prevents not only the streptozotocin-induced metabolic abnormalities but also cardiovascular complications as well as reduce the risk of development of cataract.
... Bassic acid, an unsaturated triterpene acid isolated from an ethanolic extract of the root bark exhibits hypoglycaemic effect in alloxan-induced diabetic rats. The hypoglycemic potential was also demonstrated in vitro using isolated rat diaphragm [58]. Assesment of the hypoglycemic effect of the plant extract rich in polyphenols and the possible mechanism of action was also made. ...
... The mechanisms of action include promoting regeneration of β cells of islets of langerhans in the pancreas, enhancement of insulin release and activity on the cells, decrease peripheral glucose uptake at the duodenal cellular level and other aspects of small intestine. Restriction of the rise in blood glucose levels caused by pituitary hormones responsible for inhibiting peripheral utilization of glucose as well as glycogenolysis, and the presence of high level of fibre in plants which interferes with carbohydrate absorption (88)(89)(90)(91) . The active compounds present in the plant with confirmed anti diabetic properties are given in the Table 5. ...
Diabetes mellitus (DM) is one of the oldest diseases known to man. DM is a chronic metabolic disorder resulting from a reduced insulin secretion by the pancreas or insulin action in the body or both. Currently 200 million people worldwide are found to be affected with DM and it is estimated and expected to reach 300 million by 2025. People can live normal with a healthy live by combining the elements of a balanced and nutritious diet, regular exercise or physical activity and proper medication. A regular blood glucose testing at intervals will be a guide to control the disease. Despite the publication of numerous original and review articles on the subject and availability of many natural as well as synthetic marketed products the effective management and treatment is not understood. This article highlights an overview of the historical background of the diabetes, classification (i.e., Type-I, Type-II, gestational, genetic defects of the β-cell), pathological changes and complications. It is briefed on treatment and management of the diabetes and the novel drug delivery systems such as nanoparticles, liposomes, aquasomes, emulsosomes, ethosomes, transdermals, microspheres, and implant in therapy. Thus, a better understanding concerning the DM and novel approaches in formulation technology and therapy could guide the formulation scientists and clinicians towards successful management of DM.
... Shows insulin secretaguogue effect in pancreatic cells(Naik et al., 1991, Almeida et al., 1985.Increases the beta cells production in the pancreas or may permit the recovery of partially destroyed cells and also stimulates the insulin secretion from the beta cells(Savula et al., 2012, Garau et al., 2003.Reduces the uronic acid, total amino acid, total cholesterol, triglyceride and total lipid which indicate its hypoglycemic and hypolipidemic effects (Agrawal et al., 1996,Rai et al., 1997). ...
Diabetes mellitus is a metabolic disorder characterized by hyperglycemia, hyperlipidemia, hyperaminoacidemia, and hypoinsulinaemia which leads to reduce in both insulin secretion and insulin action. It is often connected with the development of micro and macro vascular diseases which include a long term damage, dysfunction and failure of various organs especially the eye, nerves, heart, kidney and blood vessels. Various approaches have been developed for the treatment of diabetes, like insulin management and use of a variety of oral hypoglycemic agents but these synthetic drugs are costly and often associated with high chances of side effects. A wide number of medicinal plants are described in Ayurveda and traditional medicinal system which are used for the treatment of diabetes from ancient time. The present paper is an attempt to represent the list of the anti-diabetic plants, and their active constituents with a particular mechanism of action. The active principles present in medicinal plants have been reported to possess various activities such as pancreatic beta cell regeneration, stimulating insulin release, showing insulin-like action, fighting the problem of insulin resistance, and reducing the uptake, absorption and utilization of glucose. The recent development of herbal formulations for the treatment of diabetes include using combined extracts of the different plants or different parts of the same plants; development of novel targeted drug delivery systems etc. Perceived effectiveness, fewer side effects, controlled rate of drug release and targeted approaches are the recent areas of herbal technological developments.
... Tem ocorrência no Nordeste brasileiro, das restingas litorâneas e do Pantanal Mato-grossense (Agra, 1996;Delfi no et al., 2005;Lorenzi e Matos, 2008). Pode ser utilizada para diversos fi ns, arborização (Dantas e Souza, 2010), mata ciliar (Ribeiro-Filho et al., 2009), propriedades fi toterápicas (Naik et al., 1991;Agra et al., 2007). ...
The offi cial methods for testing germination of seeds of 50 species Brazilian forest
were the result of a validation process. The steps of this process ranged from the choice of species, an
extensive literature review, pre-tests with variations in temperature, photoperiod, substrate type and
moisture, asepsis, counting times and pre-germination treatments, especially for breaking dormancy, as well as metrology and statistical studies. The proposed methods for the germination of seeds of 50
species native forest cannot be the only effi cient but are safe for germination of seeds with different
qualities. This robustness of the methods culminated in the publication of Normative Instructions No.
44 of December 23, 2010, No. 35, July 14, 2011 and No. 26 of 14 September 2012 that formalized
methods for 50 Brazilian forest species. The presence of dormancy is not a determining factor for the
variances of repeatability and reproducibility, because the greatest differences between percentages of
normal seedlings occur between replications of the same lot.
... Bassic acid acts by increasing glucose uptake and glycogen synthesis in isolated rat diaphragm and plasma insulin levels. It appears that this effect was mediated by an insulin secretagogue effect in pancreatic cells [101]. ...
Diabetes mellitus is a complex metabolic disorder resulting from either insulin insufficiency or insulin dysfunc- tion. Diabetes mellitus affects most of the people in both developed and developing countries. The treatment of diabetes with synthetic drugs is costly and chances of side effects are high. Phytomedicine has been used since ancient times in various parts of the world where access to modern medicine is limited. Medicinal plants and phytoconstituents play an important role in the management of diabetes mellitus especially in developing countries where resources are meagre. Phytochemicals identified from medicinal plants present an exciting opportunity for the development of new types of therapeutics for diabetes mellitus. Most prevalent among phytochemical groups are the alkaloids, glycosides, polysaccha- rides, and phenolics such as flavonoids, terpenoids and steroids. Despite considerable progress in the development of syn- thetic drugs, the discovery of phytomedicine as an alternative therapy is progressing. This article aims to provide a com- prehensive review on various plant species from globe and their constituents, which have been shown to display potent hypoglycemic activity.
A preocupação com os problemas ambientais e os escassos conhecimentos sobre a propagação das espécies nativas, sobretudo por meio sexuado tem provocado, nos últimos anos, o interesse pelo estudo dos fatores que influenciam no processo germinativo das sementes de diferentes espécies. Nesse sentido, o presente trabalho foi realizado com o objetivo de avaliar o efeito de diferentes regimes de luz e temperaturas na germinação e vigor de sementes de quixaba - Sideroxylon obtusifolium (Roem. & Schult.) T.D. Penn., buscando determinar um protocolo eficiente para a realização do teste de germinação para as suas sementes. O experimento foi realizado no Laboratório de Análise de Sementes do Centro de Ciências Agrárias da Universidade Federal da Paraíba (CCA-UFPB), em Areia-PB. As temperaturas avaliadas foram 25, 30 e 35 °C constantes e 20-30 °C alternada, nos regimes de luz branca, verde, vermelha, vermelha-distante e escuro contínuo, adotando-se o delineamento inteiramente ao acaso, em esquema fatorial 4 x 5 (temperaturas e regimes de luz), em quatro repetições de 25 sementes cada. As variáveis analisadas foram: porcentagem de germinação, primeira contagem de germinação e índice de velocidade de germinação, bem como comprimento e massa seca de parte aérea e raiz das plântulas. As sementes germinam em todos os regimes de luz, podendo ser classificadas como fotoblásticas neutras e, as temperaturas constantes de 25 °C no regime de luz verde e 30 °C em luz vermelha-extrema favoreceu o vigor quando avaliados pela primeira contagem e índice de velocidade de germinação. Palavras-chave: Espécie nativa, Sideroxylon, Caatinga.
Diabetes mellitus (DM) is a group of metabolic disorders characterized by hyperglycemia due to insufficient insulin secretion or action. Contributing factors include genetic predisposition, obesity, family history, inactivity, and environmental risks. Type 2 diabetes mellitus (T2DM), the most common form, involves impaired insulin secretion by pancreatic β-cells, leading to insulin resistance. By 2045, it is projected that India and China will have approximately 134.3 and 110.8 million diabetic individuals, respectively. Although synthetic drugs are effective in managing DM, they often come with side effects. Consequently, plant-based phytochemicals with antidiabetic properties are gaining attention. Research indicates that around 115 medicinal plants (MPs) have antidiabetic effects, particularly those from the Fabaceae, Liliaceae, and Lamiaceae families. Bioactive compounds like alkaloids, triterpenoids, flavonoids, and phenolics are known to combat DM. Traditional medicinal systems, particularly in developing countries, offer effective DM management. This review highlights the importance of MPs and their bioactive compounds in treating diabetes and underscores the need for further research to commercialize plant-based antidiabetic drugs.
Na região do Semiárido, ocorre um dos grandes biomas brasileiro, a Caatinga, que ocupa uma área contínua, com clima quente e seco, circundada por áreas de clima mais úmido. Com o conhecimento popular como fonte de dados importantes para novas descobertas científicas sobre as propriedades terapêuticas das plantas, esse livro analisa o estado da arte de espécies nativas do semiárido brasileiro visando o desenvolvimento e a caracterização da tolerância a estresses abióticos, em espécies vegetais nativas dessa região.
Currently, there is no known cure for diabetes. Different pharmaceutical therapies have been approved for the management of type 2 diabetes mellitus (T2DM), some are in clinical trials and they have been classified according to their route or mechanism of action. Insulin types, sulfonylureas, biguanides, alpha-glucosidase inhibitors, thiazolidinediones, meglitinides, sodium–glucose cotransporter type 2 inhibitors, and incretin-dependent therapies (glucagon-like peptide-1 receptor agonists: GLP-1R, and dipeptidyl peptidase 4 inhibitors: DPP-4). Although some of the currently available drugs are effective in the management of T2DM, the side effects resulting from prolonged use of these drugs remain a serious challenge. GLP-1R agonists are currently the preferred medications to include when oral metformin alone is insufficient to manage T2DM. Medicinal plants now play prominent roles in the management of various diseases globally because they are readily available and affordable as well as having limited and transient side effects. Recently, studies have reported the ability of phytochemicals to activate glucagon-like peptide-1 receptor (GLP-1R), acting as an agonist just like the GLP-1R agonist with beneficial effects in the management of T2DM. Consequently, we propose that careful exploration of phytochemicals for the development of novel therapeutic candidates as GLP-1R agonists will be a welcome breakthrough in the management of T2DM and the co-morbidities associated with T2DM.
Medicinal plants have been largely used for the treatment of several illnesses including lifestyle diseases. The observed pharmacological properties of these plants are mainly attributed to the presence of secondary metabolites. Several of these secondary metabolites have been isolated, characterized, and assessed for their biological potential against lifestyle diseases. Reports on the chemical investigation of some medicinal plants involved in the management of lifestyle diseases such as diabetes, respiratory chronic diseases, cancer, and cardiovascular diseases have revealed that the main classes of compounds involved are phenolic compounds, terpenoids, steroids, alkaloids, etc. This chapter provides an overview of these phytoconstituents frequently involved in the management of lifestyle diseases and the various chemical techniques used for their characterization.
Diabetes mellitus (DM) is a metabolic disorder disease, and the number of diabetic patients will reach 578 million by 2030 predictably. Currently, 8 classes of small molecular drugs are used for treating diabetes. However, these drugs cannot completely meet patients' needs, due to diabetic complications need to be addressed along with diabetes, such as nephropathy, and cardiovascular diseases. Besides, more types of drugs need to be provided for more choices. Hence, scientists still seek lead compounds with hypoglycemic effects. Natural products (NPs) are a reservoir of diverse structures and bioactivities with low toxicity and less side effects. And some of them show effects on diabetic complications, which is a significant idea for drug development. This review aims to summarize natural products with hypoglycemic effects and their details, such as potential mechanisms, biological data, and particularly their advantages in treating diabetes. Considering the huge number of NPs was reported with anti-diabetic activity, and some of them need to be re-validated, this review focuses on the bioactive compounds with in vivo activities. In the end, the trend of natural products treating diabetes was discussed. We hope this review provide a comprehensive and convincing summary, thus lending support to anti-diabetic natural products research.
Introdução: Diabetes mellitus (DM) é um grupo de distúrbios metabólicos de destaque por sua alta prevalência e incidência no Brasil. Assim, a fitoterapia surgiu como uma alternativa terapêutica complementar de baixo custo para pacientes acometidos por essa patologia. Objetivo: Realizar uma revisão sistemática sobre o uso de plantas medicinais em pacientes diabéticos, definir seus mecanismos de atuação e identificar lacunas do conhecimento e desafios a serem enfrentados para sua ampla utilização. Metodologia: Realizou-se uma busca sistematizada nas bases de dados Scielo, Lilacs e PubMed. Em seguida, foram aplicados critérios de inclusão e exclusão, restando 10 artigos ao presente trabalho. Seus dados foram tabulados em 3 tabelas e, posteriormente, analisados. Resultados: Os estudos foram publicados entre os anos de 2007 e 2018, sendo cinco deles observacionais, quatro experimentais pré-clínicos e apenas um clínico. A maioria (60%) foi publicada na língua portuguesa. Dentre os estudos clínicos e pré-clínicos (50%), todos comprovaram a redução da glicemia após o tratamento com fitoterápicos específicos. Discussão: Foram identificados diversos benefícios da fitoterapia, tais como baixo custo e facilidade de obtenção. Destaque foi dado para a Bauhinia forficata e Syzygium cumini, plantas de amplo uso empírico. Os principais efeitos metabólicos proporcionados pelos fitoterápicos são a redução da glicemia e do estresse oxidativo. Identificou-se a necessidade de seguimento dos estudos na área, bem como capacitação dos profissionais e da comunidade. Conclusão: A fitoterapia apresenta-se como uma importante alternativa terapêutica para diabéticos no Brasil, contudo, lacunas do conhecimento ainda devem ser preenchidas. Palavras-chave: Diabetes Mellitus. Fitoterapia. Hipoglicemiantes. Plantas Medicinais.
Ethnopharmacological relevance
One of the commonly prescribed ‘anti-diabetic’ polyherbal mixtures by European herbalists is made of Rubus fruticosus and Vaccinium myrtillus leaves, Potentilla erecta roots, Geum urbanum aerial parts and Phaseolus vulgaris pods.
Aim of the study
This study aimed to evaluate the phytochemical composition, antioxidant capacity, potential toxicity, hypoglycemic, hypolipidemic, nephroprotective and hepatoprotective activities of this polyherbal mixture decoction.
Materials and methods
The phytochemical composition was evaluated using HPLC-UV. The antioxidant activity was assessed using the DPPH test. Potential toxicity was evaluated using the acute and sub-chronic oral toxicity method. Diabetes was induced in Wistar female rats with a single intraperitoneal injection of alloxan monohydrate (150 mg/kg). The animals whose blood glucose was >20 mmol/L for 14 consecutive days were considered diabetic. For the next 14 days, D-10 and D-20 groups were treated with the polyherbal mixture (10 and 20 g of dry plant material/kg, respectively). I and M were control groups treated with insulin glargine (13 IU/kg) and metformin (150 mg/kg), respectively. Healthy control (HC) and diabetic control (DC) groups were treated with water. The blood glucose level was measured on days 14, 21 and 28. Lipid profile analysis was done on day 28. Pancreas, kidney and liver histopathology was evaluated using the H&E and Masson’s trichrome staining. The liver tissue was additionally tested for PAS-positive cells.
Results
The HPLC-UV analysis revealed the presence of quinic, gallic and caftaric acid, arbutin, rutin, trifolin, astragalin, hyperoside, isoquercetin and quercitrin. The antioxidant activity of the extract was higher than the reference's one (p < 0.01). Treatment with the polyherbal mixture (10 and 20 g/kg) has shown no toxic effects. No major decline in blood sugar was recorded in I and M groups compared to the DC one (22.86 ± 2.58, 28.5 ± 0.42 and 27.82 ± 0.9 mmol/L, respectively). The polyherbal mixture lowered the blood glucose level to the normal value (8.64 ± 4.09, 5.26 ± 1.3 and 6.76 ± 1.54 mmol/L in D-10, D-20 and HC groups, respectively). Furthermore, it decreased the levels of total cholesterol, triglycerides, VLDL, LDL, atherogenic and cardiovascular risk indices (p < 0.001) compared to the DC group. In addition, the extract restored histopathological changes of the pancreas, kidneys and liver to the healthy animal level.
Conclusion
Treatment with the polyherbal mixture extract was more effective than the standard drugs (insulin and metformin) in the amelioration of hyperglycemia, hyperlipidemia, and histopathological changes of the pancreas, kidney and liver tissue.
Management of diabetes mellitus is a challenge for clinicians. Uncontrolled hyperglycemia increases the risk of microvascular and
macrovascular complications, damaging the body systems. Although a number of antidiabetic drugs are available for therapeutic
intervention, toxicity, loss of efficacy in chronic use and high cost of treatment have necessitated the search for new molecules to manage
diabetes. Safety and cost are the main prerequisite for the new antidiabetic molecules. Medicinal plants and their purified phytochemicals
have shown promising antidiabetic potential in the past few years. The current review summarizes the antidiabetic activity of alkaloids,
phenols, flavonoids, saponins, polysaccharides, terpenoids, glycosides and xanthones isolated from medicinal plants
Bassic acid, an unsaturated triterpene acid isolated from Mimusops elangii , was tested for its antileishmanial properties both in vitro and in vivo . The in vitro antileishmanial activity of bassic acid being encouraging, its activity in vivo was evaluated in hamster models of visceral leishmaniasis, both in free form, as well as incorporated in two different delivery systems, viz microemulsions and polylactide nanoparticles. The delivery systems were prepared by published protocols. The percentage intercalation of bassic acid in nanoparticles and microemulsion was found to be about 50 and 100, respectively, when determined at its absorption maxima (lambda(max)) 285 nm (epsilon(rn) = 2.3 x 10(2) M-1 cm(-1)). At an equivalent dose of 2 mg kg(-1) body weight, when injected subcutaneously for a total of six doses in 15 days, bassic acid was found to reduce spleen parasite loads by 45, 62 and 78% in free, microemulsion-incorporated and nanoparticle-incorporated forms, respectively. A comparison of specific biochemical tests related to normal liver and kidney functions revealed that the nanoparticulate form was successful in significantly reducing the hepatotoxicity and nephrotoxicity of the free drug, but the microemulsion delivery system was less effective and toxic to liver and kidney to some extent. Confocal microscopic images of Leishmania donovani promastigotes treated with bassic acid revealed that the drug induced necrotic cell death due to non-specific membrane damage. Because of its high efficacy as well as non-hepatotoxicity and non-nephrotoxicity, the nanoparticulate form of bassic acid may be considered for clinical application in humans rather than the microemulsion incorporated form.
Bioactive natural products are an excellent source of novel therapeutics. The search for bioactive molecules from nature continues to play a major role in developing new generation natural products of therapeutic importance. The present critical review includes research work carried out by active researchers in natural products’ chemistry, pharmacology and therapeutics, and their implications in antidiabetic medications. This compiled scientific information will be a useful resource for future research especially in indentifying promising leads and direction for the development of novel drugs including useful adjuvants for the treatment of diabetic patient.
Oxidative stress plays a major role in diabetic cardiomyopathy pathogenesis. Anti-oxidant therapy has been investigated in preventing or treating several diabetic complications. However, anti-oxidant action on diabetic-induced cardiac remodeling is not completely clear. This study evaluated the effects of rutin, a flavonoid, on cardiac and myocardial function in diabetic rats.
Wistar rats were assigned into control (C, n = 14); control-rutin (C-R, n = 14); diabetes mellitus (DM, n = 16); and DM-rutin (DM-R, n = 16) groups. Seven days after inducing diabetes (streptozotocin, 60 mg/kg, i.p.), rutin was injected intraperitoneally once a week (50 mg/kg) for 7 weeks. Echocardiogram was performed and myocardial function assessed in left ventricular (LV) papillary muscles. Serum insulin concentration was measured by ELISA. Statistics: One-way ANOVA and Tukey’s post hoc test.
Glycemia was higher in DM than DM-R and C and in DM-R than C-R. Insulin concentration was lower in diabetic groups than controls (C 2.45 ± 0.67; C-R 2.09 ± 0.52; DM 0.59 ± 0.18; DM-R 0.82 ± 0.21 ng/mL). Echocardiogram showed no differences between C-R and C. DM had increased LV systolic diameter compared to C, and increased left atrium diameter/body weight (BW) ratio and LV mass/BW ratio compared to C and DM-R. Septal wall thickness, LV diastolic diameter/BW ratio, and relative wall thickness were lower in DM-R than DM. Fractional shortening and posterior wall shortening velocity were lower in DM than C and DM-R. In papillary muscle preparation, DM and DM-R presented higher time to peak tension and time from peak tension to 50% relaxation than controls; time to peak tension was lower in DM-R than DM. Under 0.625 and 1.25 mM extracellular calcium concentrations, DM had higher developed tension than C.
Rutin attenuates cardiac remodeling and left ventricular and myocardial dysfunction caused by streptozotocin-induced diabetes mellitus.
The study was aimed at testing the hypothesis that sulfonylureas do not readily penetrate the pancreatic-cells but more probably stimulate insulin release by a direct action on the-cell plasma membrane. Uptake of radioactively labelled tolbutamide and glibenclamide by microdissected pancreatic islets of obesehyperglycemic mice was compared with the uptake of 3-O-methyl-D-glucose, to which the-cells are permeable. In contrast to tolbutamide, glibenclamide was taken up in amounts exceeding the 3-O-methyl-D-glucose space of islets incubated in the absence of serum albumin. Uptake of the sulfonylureas was easily reversible. It was depressed by serum albumin, whereas glucose, leucine or diazoxide had no effects. Antimycin A,p-chloromercuriphenylsulfonic acid and chlorpromazine, all of which increase the uptake of extracellular space markers, strongly stimulated the islet uptake of tolbutamide and glibenclamide but had no effect on the uptake of glibenclamide by subcellular particles of homogenized islets. The results suggest that sulfonylureas bind reversibly to islet tissue but are normally restricted to the outside of the-cells.
The action of blood sugar depressing sulfonylureas on glucose and oxygen uptake, as well as on glycogen content and formation of C14O2 from uniformly labelled C14-glucose was investigated in rat hemidiaphragms incubated in phosphate buffer. The following results were obtained: (1) Tolbutamide and Carbutamide increased the glucose uptake. (2) Tolbutamide decreased the glycogen-content. (3) Oxygen uptake as well as formation of C14O2 were increased by Tolbutamide. (4) The action of Tolbutamide and insuline was equal with respect to glucose uptake but different as regarding the glycogen content, oxygen uptake and CO2-formation.It is concluded that sulfonylureas increase glucose oxidation in the rat hemidiaphragm probably without increasing insulin sensitivity. To our knowledge this mechanism of action has hitherto not been described.
The following evidence suggests that diabetes mellitus may not be the simple consequence of relative or absolute insulin deficiency by itself, but may require the presence of glucagon: (1) relative or absolute hyperglucogonaemia has been identified in every form of endogenous hyperglycaemia, including total pancreatectomy in dogs; (2) insulin lack in the absence of glucagon does not cause endogenous hyperglycaemia, but when endogenous or exogenous glucagon is present, it quickly appears, irrespective of insulin levels at the time. These facts are compatible with a bihormonal-abnormality hypothesis, which holds that the major consequence of absolute or relative insulin lack is glucose underutilisation and that absolute or relative glucagon excess is the principal factor in the over-production of glucose in diabetes.
The effect of sulfonylureas on insulin and glucagon secretion is reviewed. Although these agents stimulate insulin release acutely, a chronic effect to increased insulin levels is usually not found. Both in vivo and in vitro experiments are inconsistent regarding the effects of sulfonylureas on glucagon release. Studies in the perfused rat pancreas suggest the effect of tolbutamide on glucagon secretion is concentration dependent: low concentrations are stimulatory and high concentrations become inhibitory. Inhibitory effects may be secondary to concomitant increased insulin. However, studies presented using exogenous insulin and pancreas from the streptozotocin-treated rat suggest tolbutamide also may act directly to inhibit glucagon secretion. Effects of increased K+ and tolbutamide were similar, suggesting depolarization and resultant ion flux may be the predominant mechanism of sulfonylurea action.
Glucagon suppression by somatostatin reduces or abolishes hyperglycemia in dogs made insulin-deficient by somatostatin, alloxan, or total pancreatectomy. This suggests that the development of severe diabetic hyperglycemia requires the presence of glucagon, whether secreted by pancreatic or newly identified gastrointestinal A cells, as well as a lack of insulin. Glucagon suppression could improve therapeutic glucoregulation in diabetes.
Bumelia sartorum has been mentioned in Brazilian folklore for its reputed use in the treatment of diabetes mellitus and inflammatory disorders. An ethanol extract of root bark elicited a hypoglycemic effect in normal and alloxan-induced diabetic rats. In addition, the extract altered glucose tolerance in alloxan-induced diabetic rats, enhanced glucose uptake in skeletal muscle and significantly inhibited glycogenolysis in the liver. These results indicate that the hypoglycemic effect may be similar to chlorpropamide and possibly due to an enhanced secretion of insulin from the islets of Langerhans or an increased utilization of glucose by peripheral tissues. Besides hypoglycemic activity, the ethanol extract also elicited significant anti-inflammatory activity, but did not show any significant effects on blood pressure, respiration or on the various isolated tissue preparations studied. Basic acid has been isolated from the ethanol extract and this component may be responsible for the observed anti-inflammatory activity. However, it is yet to be established whether basic acid is responsible for the observed hypoglycemic activity of the ethanol extract.
Charcoal premixed with dextran of average molecular weight 80,000 almost instantly adsorbs free insulin but rejects antibody-bound insulin. The use of such dextran-coated charcoal makes simpler and more rapid the immunoassay of insulin in biologic fluids, using radioisotope dilution with 131I-insulin and “biopsy” of the insulin pool by antibody to insulin. The procedure here described yields a straight line graph when insulin added is plotted against insulin recovered.
The role of endogenous glucagon and somatostatin in insulin release was studied. Islets isolated from adult rats were incubated for 60 min in 3.3, 8,3 and 16.7 mM glucose with anti-glucagon antiserum (AGA) or anti-somatostatin antiserum (ASA) which was produced in rabbits. For the control experiments the antiserum was replaced by normal rabbit serum (NRS). Insulin release from islets treated with AGA was suppressed in 3.3 and 8.3 mM glucose as compared to islets treated with NRS, while insulin release was not affected in 16.7 mM glucose. On the other hand, insulin release from islets treated with ASA was enhanced in 3.3 and 8.3 mM glucose as compared to that from islets treated with NRS, whereas in 16.7 mM glucose it was not different from the control. These observations indicate that endogenous glucagon and somatostatin play a physiological role in the regulation of insulin release, but their regulation of insulin release is deranged at non-physiologically high glucose concentrations.
Tolbutamide and carbutamide given orally to fasted rats cause a rise in the liver glycogen content 1(1/2) to 3(1/2) hr. after administration of the drugs. Glycogen accumulates preferentially in the right lobe. Subcutaneously injected tolbutamide has the same effect. Both sulphonylureas cause inhibition of glucose-6-phosphatase activity of rat liver homogenates in vitro, but at drug concentrations comparable with those found in plasma of treated patients the degree of inhibition is less than 10%. Livers from treated rats show normal glucose-6-phosphatase activity. The glucose uptake of the isolated rat diaphragm is unaffected by the sulphonylureas added in vitro. Diaphragms from treated rats show normal glucose uptake in the presence or absence of insulin. The inferences to be drawn from these results are discussed in the light of previous work. It is concluded that the sulphonylureas exert hypoglycaemic action by inhibiting glycogenolysis and it is suggested that they might do so by inhibiting release of glucagon from the pancreas.
For years investigators have sought an assay for insulin which would combine virtually absolute specificity with a high degree of sensitivity, sufficiently exquisite for measurement of the minute insulin concentrations usually present in the circulation. Methods in use recently depend on the ability of insulin to exert an effect on the metabolism of glucose in vivo or in excised muscle or adipose tissue. Thus, the insulin concentration in plasma has been estimated: a) from the degree of hypoglycemia produced in hypophysectomized, adrenalectomized, alloxan-diabetic rats (1); b) from the augmentation of glucose uptake by isolated rat hemidiaphragm (2); or c) from the increased oxidation of glucose-1-C14 by the rat epididymal fat pad (3). Since there have been reports indicating the presence, in plasma, of inhibitors of insulin action (4) and of noninsulin substances capable of inducing an insulin-like effect (5,6), these procedures, while yielding interesting information regarding the effects of various plasmas on glucose metabolism in tissues, are of doubtful specificity for the measurement of insulin per se (5).
Preliminary studies on the hypoglycemic activity of crude extract of Guettarda angelica
- Tavares