Article

Antihyperglycemic, Antihyperlipidemic and Modulatory Effects of Apple Cider Vinegar on Digestive Enzymes in Experimental Diabetic Rats

Authors:
  • High school of sciences and technics of health
  • Higher School of Health Sciences and Technics, University of Tunis El Manar, Tunis, Tunisia
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Abstract

Background: Apple Cider Vinegar (ACV) is an ancient folk remedy and it is common for patients with diabetes daily because of its positive effect on blood glucose and insulin sensitivity. The present study was undertaken to investigate the possible antihyperglycemic and antihyperlipidemic effects of ACV, particularly in terme of its inhibitory effects on some carbohydrate metabolising enzymes in the intestine and the livers in normal and diabetic rats. Materials and Methods: The assays of the present study were conducted on adult male Wistar rats. The animals were fasted overnight and diabetes mellitus was induced by an intraperitoneal injection of freshly prepared streptozotocin (STZ). Control rats were injected with citrate buffer only. The ACV was administrated orally during 4 weeks. Results: Our findings indicated that the admnistration of ACV significantly decreased intestinal maltase, sucrase and lactase and hepatic glucokinase (GK) activities which led to a significant decrease in blood glucose rate and an increase in hepatic glycogen levels. In addition to that, significant increase in hepatic phosphofructokinase (PFK) and glucose 6 dehydrogenase (G6PDH) was observed. Moreover, the treatment with ACV potentially inhibited key enzymes of lipid metabolism and absorption such as lipase activity in small intestine which led to a notable decrease in serum Total Cholesterol (TC), Low Density Lipoprotein-cholesterol (LDL-c) and triglyceride (TG) rates and an increase in High Density Lipoprotein-cholesterol (HDL-c) levels. The ACV was also observed to protect the liver-kidney functions efficiently, which were evidenced by the significant decrease in the serum aspartate and lactate transaminases (AST and ALT) activities and the level of total and direct bilirubin, creatinine and urea. Conclusion: The present findings showed that ACV significant improves glucose and lipid homeostatis in diabetes by delaying carbohydrate and lipid digestion and absorption.

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... The inhibition of carbohydrate hydrolyzing enzymes could decrease postprandial hyperglycemia [34]. Numerous studies proved the ability of apple vinegar to reduce hyperglycemia [35][36][37][38]. In this context, the activity on α-glucosidase and α-amylase inhibition of the two samples of apple vinegar produced by different techniques were evaluated ( Table 4). ...
... The inhibition of both enzymes contributes to the management of type 2 diabetes through suppression or interrupting glucose generation carbohydrates absorption [33]. Diminution of carbohydrates hydrolyzing is considered as one of the successful approaches to reduce hyperglycemia and hyperlipidemia [38]. There are many bioactive substances such as terpenes (22-a hydroxychiisanoside) and alkaloids (palmatine) that can inhibit αglucosidase and α-amylase enzymes [39,40]. ...
... Moreover, syringic, vanillic, and sinapic acids, present in both artisanal and industrial vinegars (Table 5), inhibit α-amylase and α-glucosidase activities through a specific binding between methoxy group of their aromatic ring and the active sites of these enzymes, which could be the target pathway involved by other hydroxycinnamic and hydroxybenzoic acids identified in our vinegar samples [45]. Furthermore, acetic acid, as a major organic acid present in apple vinegar, was suggested as a key factor in reducing disaccharidase activity, intestine maltase, lactase, and sucrase activities [38,46]. In the same context, the administration of acetic acid suppressed carbohydrates hydrolyzing enzymes (sucrase, maltase, lactase, and trehalase) [46]. ...
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The main objective of the current study was to determine the physicochemical properties, antioxidant activities, and α-glucosidase and α-amylase inhibition of apple vinegar produced by artisanal and industrial methods. Apple vinegar samples were analyzed to identify their electrical conductivity, pH, titratable acidity, total dry matter, Brix, density, mineral elements, polyphenols, flavonoids, and vitamin C. The antioxidant activity of apple vinegar samples was evaluated using two tests, total antioxidant capacity (TAC) and DPPH radical scavenging activity. Finally, we determined α-glucosidase and α-amylase inhibitory activities of artisanal and industrial apple vinegar. The results showed the following values: pH (3.69–3.19); electrical conductivity (2.81–2.79 mS/cm); titratable acidity (3.6–5.4); ash (4.61–2.90); ◦Brix (6.37–5.2); density (1.02476–1.02012), respectively, for artisanal apple vinegar and industrial apple vinegar. Concerning mineral elements, potassium was the most predominant element followed by sodium, magnesium, and calcium. Concerning bioactive compounds (polyphenols, flavonoids, and vitamin C), the apple vinegar produced by the artisanal method was the richest sample in terms of bioactive compounds and had the highest α-glucosidase and α-amylase inhibition. The findings of this study showed that the quality and biological activities of artisanal apple vinegar were more important than industrial apple vinegar
... Apple vinegar is widely used and appreciated by the Moroccan population and around the world. Several studies clearly demonstrated many benefits of vinegar consumption such as glucose-lowering effect in patient with glucose abnormalities [16][17][18], improved insulin sensitivity in insulinresistant patients [19], decreasing the glycemic index of carbohydrate food for people with and without diabetes [19], antihyperlipidemic [18], hepatoprotective effect [20,21], and modulation of lipid peroxidation [22]. ...
... Apple vinegar is widely used and appreciated by the Moroccan population and around the world. Several studies clearly demonstrated many benefits of vinegar consumption such as glucose-lowering effect in patient with glucose abnormalities [16][17][18], improved insulin sensitivity in insulinresistant patients [19], decreasing the glycemic index of carbohydrate food for people with and without diabetes [19], antihyperlipidemic [18], hepatoprotective effect [20,21], and modulation of lipid peroxidation [22]. ...
... The intake of apple vinegar ameliorates the insulin sensitivity and increase the uptake of glucose in the skeletal muscles [17]. Acetic acid (a major component of vinegar) was suggested as a key to slowing down of gastric emptying [34] and decreasing of disaccharidase activity in the small intestinal [15], intestine maltase, lactase, and sucrose activities [18]. Additionally, it promotes the uptake of glucose by muscle performance [17,36], consequently, decreasing fasting blood glucose. ...
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The main objective of this study is to determine the effects of apple vinegar on the metabolic changes caused by hypercaloric diet in Wistar rats. Apple vinegar was first analyzed to find out the total acidity, the polyphenolic and flavonoid contents, the total antioxidant capacity, and the free radical scavenging activity. In vivo study on adult male and female Wistar rats was conducted by administering a drink containing either 10% D-glucose or water (control) for five weeks. Apple vinegar is administered daily by gavage (2 mL/kg) to rats fed D-glucose for 5 weeks. The results showed that the polyphenolic content in apple vinegar was 148.02±10.16 mg GAE/100 mL, flavonoid content was 22.93±0.73 QE/100 mL, and total antioxidant capacity was 13.4±0.47 mg AAE/100 mL. Free radical IC50 apple vinegar scavenging activity (DPPH) was 0.74±0.154 μL/mL. The total acidity was (3.24±0.02 mg AAE/100 mL). The treatment during five weeks with D-glucose leads to increased plasma glucose, lipid profile, hepatic enzyme levels, urea, and creatinine. Simultaneous treatment with apple vinegar improves the parameters studied. These results clearly show that the daily consumption of vinegar can reduce the rise in blood sugar and lipid profile induced by hypercaloric diet in rats. Therefore, the use of apple vinegar would have a very beneficial effect in the prevention of metabolic disorders caused by high-caloric food.
... Several mechanisms may explain the ways in which acetic acid lowers plasma glucose have been suggested. These include inhibition of disaccharidase activity [23][24][25] and/or decrease in the hydrolytic enzyme α-amylase [26], delayed gastric emptying [27,28] and an enhanced glucose uptake and conversion to glycogen in the periphery [23,29,30]. ...
... Several mechanisms may explain the ways in which acetic acid lowers plasma glucose have been suggested. These include inhibition of disaccharidase activity [23][24][25] and/or decrease in the hydrolytic enzyme α-amylase [26], delayed gastric emptying [27,28] and an enhanced glucose uptake and conversion to glycogen in the periphery [23,29,30]. ...
... It was suggested that suppression of the disacharrides may occur in the post-translational processes, such as trafficking of the enzymes to the cell membrane [24]. Consumption of 100mL ACV (5% acetic acid) in diabetic rats demonstated a significant decrease in the activity of maltase, sucrase and lactase [23]. In addition, vinegar ingestion (10g) was found to have no effect on postprandial glycemia (PPG) when only monosaccharides were ingested while a meal of complex carbohydrates consumed with vinegar did result in decreased PPG, further indicating that a acetic acid may inhibit disaccharidase activity [31]. ...
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Type 2 Diabetes represents a large burden on public health systems worldwide. The chronic metabolic condition is characterised by hyperglycaemia and insulin resistance and is frequently associated with obesity, hypertension and dyslipidaemia. There is a growing need for effective management techniques of these conditions that patients can utilise complementary to conventional therapy. Apple cider vinegar (ACV) has been the subject of growing interest in this field. The main component of ACV, acetic acid, has demonstrated effectiveness in reducing hyperglycaemia, correcting dyslipidaemia and assisting weight loss. The dominant polyphenol compound in ACV, chlorogenic acid may also be useful in managing the condition.
... All studies found some lowering effects of AV on either blood glucose/HbA1c [17,[53][54][55][56][57][58] or blood lipid levels [17,40,[53][54][55][56][57][58][59][60][61][62]. The study by Shishehbor et al. [54] found no effect on fasting glucose, but a decreasing effect on HbA1c, while Budak et al. [40] found that AV consumption increased TC compared to controls (p < 0.05). ...
... All studies found some lowering effects of AV on either blood glucose/HbA1c [17,[53][54][55][56][57][58] or blood lipid levels [17,40,[53][54][55][56][57][58][59][60][61][62]. The study by Shishehbor et al. [54] found no effect on fasting glucose, but a decreasing effect on HbA1c, while Budak et al. [40] found that AV consumption increased TC compared to controls (p < 0.05). ...
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IntroductionApple vinegar (AV) has been proclaimed to have different health benefits, such as a weight loss, the ability to lower blood glucose levels, and reducing the risk of heart diseases. Studies on animals have demonstrated effects of AV consumption, deepening our knowledge of the beneficial effects and side effects.AimThe aims of this study were to evaluate the evidence of the effect of AV on metabolic parameters and body weight in humans, furthermore, to evaluate the safety and side effects of ingesting AV, and additionally to evaluate the evidence of the effect of AV on metabolic parameters, safety, and side effects of AV from studies performed on animals (mammals).MethodsA systematic literature search was performed. The databases PubMed (MEDLINE), PsycInfo (Ebsco), CINAHL (Ebsco), and Embase (Ovid) were searched for relevant articles. Primary outcomes were glycated hemoglobin, postprandial glucose, and synonyms for blood glucose. Secondary outcomes were waist circumference, visceral fat, high-density lipoprotein, low-density lipoprotein, triglycerides, and total cholesterol. Studies performed on humans and animals were included. The included studies performed on humans were quality assessed for risk of bias using a version of the Cochrane Collaboration’s tool.ResultsA total of 487 papers were identified in the literature search. Of these, 13 studies performed on humans and 12 studies performed on animals were included. There may be beneficial health effects from the consumption of AV. The risk of side effects when ingested in recommended quantities and in recommended ways seems inconsiderable.Conclusion Due to inadequate research of high quality, the evidence for the health effects of AV is insufficient. Therefore, more large-scale, long-term clinical studies with a low risk of bias are needed before definitive conclusions can be made.
... A large number of natural products are widely used in folk medicine to prevent and/or to alleviate anemia, including herbs and bee products [27][28][29]. Additionally, fruit by-products such as apple vinegar have been documented as having several biological properties due to its rich composition in phenolic compounds [30][31][32][33][34][35][36][37][38]. Apple vinegar is considered to be an antioxidant, antihyperglyceamic, antihyperlipidimic and hepato-nephroprotective agent [39][40][41][42]. ...
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This study aims to examine the ability of apple vinegar on phenylhydrazine (PHZ)-induced hemolytic anemia in Wistar rats. In vitro, phenolic and flavonoid content and antioxidant activity were determined. In vivo, phenylhydrazine (10 mg/kg) was injected intravenously into rats for 4 days and then treated with apple vinegar daily by gavage (1 mL/kg) for five weeks. high level of polyphenols and flavonoids (90 ± 1.66 mg GAE/100 mL and 7.29 ± 0.23 mg QE/100 mL, respectively) were found in the apple vinegar which gives it a good ability to scavenge free radicals (TAC = 4.22 ± 0.18 mg AAE/100 mL and DPPH, IC50= 0.49 ± 0.004 µL/mL). The phytochemical composition of apple vinegar revealed the presence of numerous bioactive compounds including arbutin, apig-enin, sinapic, ferulic and trans-ferulic acids. The major antioxidant components in apple vinegar were ferulic and trans-ferulic acids (40% and 43%, respectively). PHZ treatment induced changes in platelets, blood cell count, mean corpuscular volume, hemoglobin concentration and mean capsu-lated hemoglobin. However, the co-administration of apple vinegar revealed its capacity to ameliorate the changes induced by phenylhydrazine. Therefore, apple vinegar use could have a positive impact on the prevention of hemolytic anemia induced by phenylhydrazine due to the antioxidant properties of its major components.
... This finding, though inconclusive, suggests that Nypa fruticans Wurmb.'s AE can act as a hepatoprotective agent. Similar findings were observed by Halima et al. [40] and Omar et al. [16] when studying the effect of apple cider vinegar on the livers of diabetic rats. ...
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