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Aqueous extract of Zizyphus jujuba fruit attenuates glucose induced neurotoxicity in an in vitro model of diabetic neuropathy

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The neuroprotective effect of fruit aqueous extract of Ziziphus jujuba Lam on glucose-induced neurotoxicity in PC12 cells as an appropriate in vitro model of diabetic neuropathy was investigated. Cell viability was determined by the MTT assay. Cellular reactive oxygen species (ROS) generation was measured by DCFH-DA analysis. Cleaved caspase-3, a biochemical parameter of cellular apoptosis, was measured by western blot analysis. Our data showed that a 4-fold elevation in glucose levels within the medium significantly reduced cell viability, increased intracellular ROS and caspase-3 activation in PC12 cells after 24 hr. Incubation of the high glucose medium cells with 300-μg/ml Z. jujuba fruit (ZJF) extract decreased the high glucose-induced cell toxicity and prevented caspase-3 activation and excited ROS generation. Thus, we concluded that the aqueous extract of Z. jujuba protects against hyperglycaemia-induced cellular toxicity. This could be associated with the prevention of ROS generation and neural apoptosis. Moreover, the results suggest that the ZJF has a therapeutic potential to attenuate diabetes complications such as neuropathy.
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Iranian Journal of Basic Medical Sciences
ijbms.mums.ac.ir
Aqueous extract of
Zizyphus jujuba
fruit attenuates glucose
induced neurotoxicity in an
in vitro
model of diabetic
neuropathy
Ayat Kaeidi 1, Majid Taati 1*, Zahra Hajializadeh 2, Faranak Jahandari 2, Marzieh Rashidipour 3
1 Department of Physiology, School of Veterinary Medicine, Lorestan University, Khorramabad, Iran
2 Kerman Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran
3 Young Researchers Club, Khoramabad Brach, Islamic Azad University, Khoramabad, Iran
A R T I C L E I N F O
A B S T R A C T
Article type:
Short communication
Objective(s): The neuroprotective effect of fruit aqueous extract of Ziziphus jujuba Lam on glucose-
induced neurotoxicity in PC12 cells as an appropriate in vitro model of diabetic neuropathy was
investigated.
Materials and Methods: Cell viability was determined by the MTT assay. Cellular reactive oxygen
species (ROS) generation was measured by DCFH-DA analysis. Cleaved caspase-3, a biochemical
parameter of cellular apoptosis, was measured by western blot analysis.
Results: Our data showed that a 4-fold elevation in glucose levels within the medium significantly
reduced cell viability, increased intracellular ROS and caspase-3 activation in PC12 cells after 24 hr.
Incubation of the high glucose medium cells with 300-μg/ml Z. jujuba fruit (ZJF) extract decreased the
high glucose-induced cell toxicity and prevented caspase-3 activation and excited ROS generation.
Conclusion: Thus, we concluded that the aqueous extract of Z. jujuba protects against hyperglycaemia-
induced cellular toxicity. This could be associated with the prevention of ROS generation and neural
apoptosis. Moreover, the results suggest that the ZJF has a therapeutic potential to attenuate diabetes
complications such as neuropathy.
Article history:
Received: Apr 30, 2014
Accepted: Oct 14, 2014
Keywords:
Apoptosis
Diabetes
Neuropathy
Ziziphus jujube
Please cite this paper as:
Kaeidi A, Taati M, Hajializadeh Z, Jahandari F, Rashidipour M. Aqueous extract of
Zizyphus jujuba
fruit attenuates glucose induced
neurotoxicity in an
in vitro
model of diabetic neuropathy. Iran J Basic Med Sci 2015; 18:301-306.
Introduction
Diabetes mellitus is one of the most frequent
metabolic disorders that cause various central and
peripheral nervous system complications such as
neuropathy (1, 2). However, the exact mechanisms for
the pathogenesis of glucose neurotoxicity remain
unclear. Current therapeutic approaches are unable to
completely relieve the neuropathic complications such
as loss of sensation, pain and motor weakness (2).
Incurable diabetic side effects are typically related to
sustained high glucose concentrations; consequently,
chronic hyperglycaemia is considered to be a key
pathogenic factor of diabetic neuropathy and tissue
damage (3, 4). Both basic and clinical studies suggest
that the oxidative stress caused by hyperglycaemia
plays an important role in the pathogenesis of
neurotoxicity (2). Oxidative stress is stimulated by
glucose through a combination of free radical
production and decreased free radical scavenging.
Hydrogen peroxide is produced by the action of
superoxide dismutase on superoxide, and it is
produced in the mitochondria by elevated oxidative
metabolism of glucose (5). Elevated cellular oxidative
stress induced by hyperglycaemia stimulates several
glucose metabolic pathways that are associated with
neuropathy progression. These include protein kinase
C (PKC) activation, NADPH redox imbalances, sorbitol
and fructose accumulation, activation of nuclear
enzyme poly (ADP-ribose) polymerase, increased
hexosamine pathway activity and superoxide
overproduction and reduced levels of crucial anti-
oxidative enzymes (2, 6).
Apoptosis is suggested as a potential mechanism
for high glucose-induced neural cell death by both in
vitro and in vivo studies (7, 8). Several forms of
chemical and physiological inducers of oxidative
stress can promote apoptotic cell death. For example,
hydrogen peroxide can induce apoptosis in various
cell types, and this effect can be inhibited by
antioxidants (9). Studies have shown remedial
properties of natural products or their active
components, and antioxidant therapy in the prevention
and/or treatment of chronic diseases such as
neurodegenerative and cardiovascular disorders (10).
Ziziphus jujuba is broadly distributed in Iran, and
the fruit of this plant has gained wide attention in
*Corresponding author: Majid Taati. Department of Physiology, School of Veterinary Medicine, Lorestan University, Khorramabad, Iran. Tel: +98 661-
6200109; email: Taatimajid@yahoo.com
Zizyphus jujuba attenuates neurotoxicity Kaeidi et al
Iran J Basic Med Sci, Vol. 18, No. 3, Mar 2015
302
folk herbal medicine for the treatment of a wide
range of disorders. Chemical analysis of the Z. jujuba
fruit revealed that it contains flavonoids (quercetin
and kaempferol) and phloretin derivatives (11). In
our pervious study, we demonstrated the anti-
oxidant activity of Z. jujube in the central nervous
system and improvements on spatial memory
deficits induced by ethanol toxicity in rats (12).
In the present study, we evaluated the effect of
the Z. jujuba fruit (ZJF) aqueous extract on glucose
induced neurotoxicity, and the potential anti-
apoptotic effect of this extract on high glucose-
treated pheochromocytoma (PC12) cells as an in
vitro model of diabetic neuropathy. PC12 cells, which
are derived from catecholamine-secreting adrenal
chromaffin tumour in rats, are appropriate model for
the assessment of neuronal cell death.
Materials and Methods
Materials
Dulbecco’s modified Eagle’s medium (DMEM),
fetal bovine serum (FBS), heat-inactivated horse
serum (HS), penicillinstreptomycin solution and
trypsin EDTA were purchased from Gibco BRL
(Grand Island, NY, USA). Culture dishes were
obtained from SPL Life sciences Inc. (Gyeonggi-Do,
South Korea). 3-[4,5-Dimethyl-2-thiazolyl]-2,5-
diphenyl-2-tetrazolium bromide (MTT) and
dichlorofluorescein diacetate (DCFH-DA) were
acquired from Sigma (St. Louis, MO, USA). D-(+)-
glucose powder was acquired from Merck Chemicals
(Darmstadt, Germany). Primary monoclonal anti-β-
actin and primary polyclonal anti-caspase 3
antibodies were purchased from Cell Signaling
Technology, Inc. (Beverly, MA, USA).
Preparation of extract
Fresh ripened fruits of Z. jujuba were obtained
from local herbal shops of Khoramabad, Iran during
the October to November, 2012. Identification of the
plant was certified at the botany department of
Lorestan University, Lorestan, Iran. Seeds were
separated from fruits and about seven hundred
grams of the pulp material were ground into fine
powder. The powder was extracted three times with
distilled water (1500 ml totally). It was centrifuged
at 4°C for 20 min at 4000 g, and the supernatant was
collected, lyophilized and stored at -20°C until use.
The extract was weighed and dissolved in phosphate
buffered saline (PBS) to give 10 mg/ml extract as
stock aliquot.
Cell culture
PC12 cells were obtained from Pasteur Institute
(Tehran, Iran). PC12 cells were cultured in high
glucose DMEM supplemented with 10% fetal bovine
serum, 5% heat-inactivated horse serum, penicillin
(100 U/ml) and streptomycin (100 μg/ml) at 37 °C in
a humidified atmosphere (90%) containing 5% CO2.
Growth medium was renewed three times a week.
Differentiated PC12 cells were plated at the density
of 5000 per well in a 96 micro plate well for the cell
viability assay. Control cells were grown in DMEM
with 25 mM glucose, and the other cells (high
glucose-treated) grown in DMEM with 100 mM
glucose. For protein extraction, cells were grown in a
6 well plate and allowed to attach and grow for 24
hr. Then the cells were incubated in medium
containing 100 mM glucose and different
concentration of ZJF extract for 24 hr.
Cell viability assay
The cell viability was explored with MTT assay.
This method is based on reduction of 2-
(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium
bromide (MTT) to formazan. MTT (0.5 mg/ml) was
added to the 96-well plates and the cells were
incubated for 2 hr at 37°C. After removing medium,
the resulting formazan was solubilized in 100 μl
Dimethyl sulfoxide (DMSO) per well. The optical
density was determined at 570 nm by an automatic
microplate reader (Eliza MAT 2000, DRG
Instruments, GmbH). Results were expressed as
percentages of control.
Intracellular ROS generation assay
Generation of intracellular reactive oxygen
species (ROS) was assessed by the oxidative-
sensitive fluorescent probe DCFH-DA. After
treatment of cells with high-glucose media and ZJF
extract, attached cells were washed twice with PBS.
PC12 Cells were loaded with 10 μM DCFH-DA in
culture media and incubated at 37 °C for 30 min.
Extra DCFH-DA was excluded by washing with fresh
PBS tree times. One hundred micro liter of phosphate
buffered saline was added to each well. Fluorescence
was evaluated with a micro-plate reader (Perkin
Elmer Victor 2) at 485 nm for excitation and at 530
nm for emission.
Western blot analysis
Western blot analysis was used to detect caspase-
3 activation in PC12 cells. In brief, cultured cells
were collected by trypsin-EDTA (0.5%), followed by
two washes with cold PBS and lysed in cold lysis
buffer [10 mM TrisHCl (pH 7.4), 1 mM EDTA, 0.1%
sodium dodecyl sulphate (SDS), 0.1% Na
deoxycholate, 1% NP-40; 2 μg each of the protease
inhibitors aprotinin, leupeptin, and pepstatin A; and
0.5 μmol/l PMSF] and incubated on ice for 30 min.
The homogenate was centrifuged twice at 14000
rpm at 4°C for 20 min. The resulting supernatant was
removed to clean tubes as the whole cell fraction.
Protein concentrations of each fraction were
measured with the Bradford method (Bio-Rad
Laboratories, Muenchen, Germany). The protein
samples from each fraction were separated via 10%
sodium dodecyl sulphate- poly acrylamide gel
Kaeidi et al Zizyphus jujuba attenuates neurotoxicity
Iran J Basic Med Sci, Vol. 18, No. 3, Mar 2015
303
Figure 1. Effect of glucose on PC12 cell viability. PC12 cells
exposed to increasing levels of glucose. Cell viability was
determinate by MTT assay. Data are expressed as mean ± SD; n = 5
to 6 wells for each group; ** P<0.01 and *** P<0.001 compared to
control cells
electrophoresis (SDS/PAGE), and subsequently
transferred to PVDF membrane for western blotting.
Membranes were probed using rabbit monoclonal
antibody to caspase-3 (Cell Signaling Technology,
USA, 1:1000 overnight at 4ºC), and subsequently
exposed to secondary HRP-conjugated IgG. Antigen-
antibody complexes were then visualized by ECL
system and exposed to Lumi-Film chemiluminescent
detection film (Roch, Germany). Beta-actin
immunoblotting (antibody from Cell Signaling
Technology, INC. Beverly, MA, USA; 1:1000) was
used as control for loading. Photographs were
digitized and the band intensity was quantified using
Lab Work analyzing software (UVP, UK).
Statistical analyses
All results are presented as the mean±SD The
difference in cell viability (mean MTT assay)
between groups was determined by one-way
ANOVA, followed by the Tukey test. The values of
caspase 3, and beta-actin band density were
expressed as tested cleaved caspase-3/beta-actin
ratio for each sample. A probability level of P<0.05
was considered significant.
Results
Analysis of cell viability
Since the optimal glucose concentration for PC12
cell cultures is 25 mM, we simulated in vitro
Figure 3. Effects of various doses of Ziziphus jujuba fruit (ZJF)
extract on high glucose-treated PC12 cell viability. High-glucose
medium reduced cell viability and ZJF extract (300 μg/ml)
protected the PC12 cells against high-glucose-induced cell death.
Data are expressed as mean±SD; n = 5 to 6 wells for each group;
** P<0.01 and *** P<0.001 compared to high glucose-treated cells
Figure 2. Effects of various doses of Ziziphus jujuba fruit (ZJF)
extract for 24 hr on PC12 cells viability. Cell viability was
determinate by MTT assay. Data are expressed as mean ± SD; n =
56 wells for each group
hyperglycemia by increasing the medium glucose
level at the concentrations of 50, 75, 100, 125 and
150 mM for 24 hr. PC12 cells exposed to increasing
levels of glucose at 50, 75, 100, 125 and 150 mM
exhibited toxicity, reaching a maximal effect in 100
mM glucose, which resulted in 49.6±12.82% of
relative cell viability. The glucose concentration of
100 mM was selected for further study as
representative of hyperglycemic conditions that can
decrease the viability of PC12 cells for assessing the
protective effects of the ZJF extract (Figure 1). In this
study, 24 hr treatment of cultured PC12 cells with
different doses of ZJF extract did not show toxic
effects (Figure 2). As shown in Figure 3, ZJF extract in
the dose of 300 μg/ml significantly inhibited high
glucose-induced toxicity in PC12 cells after 24 hr;
whereas, ZJF extract could not prevent cell damage in
other concentrations (Figure 3).
Analysis of ROS generation assay
To examine the intracellular ROS in the
hyperglycemic condition, we used the DCFH-DA
fluorescent method. As shown in Figure 4, the levels
of DCF-DA fluorescence in PC12 cells treated 24 hr
with high glucose media were increased markedly
compared to control cells. Furthermore, treatment
with 300 μg/ml ZJF extract significantly decreased
the production of the reactive oxygen spices in
hyperglycemic cells (Figure 4).
Figure 4. Effects of Ziziphus jujuba fruit (ZJF) extract on glucose-
induced ROS production in PC12 cells. ROS production was
evaluated by fluorescent probe DCFH-DA assay. ZJF extract (300
μg/ml) decreased glucose-induced ROS production. Data are
expressed as mean±SD; n= 5 to 6 wells for each group; *** P<0.001
compared to control cells
Zizyphus jujuba attenuates neurotoxicity Kaeidi et al
Iran J Basic Med Sci, Vol. 18, No. 3, Mar 2015
304
Figure 5. The activation of caspase-3 protein in PC12 cells
exposed to high glucose medium and high-glucose plus 300 μg/ml
of Ziziphus jujuba fruit (ZJF) extract for 24 hr. Caspase 3 activity
was determinated by Western blotting. Each value in the graph is
the mean ± SD band intensity for each group. Beta-actin was used
as an internal control. **P < 0.01 compared to control cells
The effect of hyperglycemic condition on the levels
of caspase-3 activation
We examined caspase-3 activation by western blot
analysis to evaluate the potential activity of ZJF on
preventing apoptosis after glucose induced
cytotoxicity in PC12 cells. The PC12 cells were
categorized to several groups including control, high
glucose media and high-glucose media plus different
concentrations of ZJF extract. As shown in Figure 5, 24
hr incubation with glucose at 100 mM enhanced
expression of procaspase-3 protein compared to the
control and vehicle groups. Caspase-3 activation was
increased in glucose treated cells after 24 hr.
Furthermore, treatment of PC12 cells with 300 μg/ml
ZJF significantly antagonized high glucose-induced up-
regulation of cleaved caspase-3 (Figure 5).
Discussion
It is well known that diabetes and hypergly-
caemic conditions elevate the formation of reactive
oxygen species (ROS) and decrease the cellular
antioxidant defence capacity (5). Oxidative stress is a
main contributor to the development of neuropathy
in diabetes. Hyperglycaemia produces oxidative
stress, which leads to the production of superoxide
and hydroxyl radicals, which in turn have direct toxic
effects on nerve tissue (13). Also, caspase (such as
caspase-3 and -9) activation reportedly increases in
high glucose conditions (13-16). Our data in the
present study revealed that glucose-induced toxicity
in PC12 cells is mediated through ROS generation
and apoptosis. Furthermore, 300 μg/ml ZJF aqueous
extract successfully decreased the high glucose-
induced ROS generation and suppressed the
activation of caspase-3, an apoptosis biomarker.
ROS can cause cell death through apoptosis (17).
Chemical and physiological oxidative stress inducers
can promote apoptosis by producing additional ROS.
For example, hydrogen peroxide can induce
apoptotic cell death in several cell types (9). The
mechanism by which oxidative stress induces
apoptosis is not well understood. Several pathology
situations can result from the oxidative stress-
induced apoptotic signalling that follows ROS
elevation and/or antioxidant diminutions, the
disruption of intracellular redox homeostasis and
irreversible oxidative reforms of DNA, lipids and
proteins (18). Furthermore, caspase-3 activation
through oxidative stress is important in the
promotion of diabetic neuropathy (6).
In recent years, the demonstration of anti-
oxidative and neuroprotective characters of natural
herbal products has drawn attention. It is notable
that several natural herbal products reportedly
protect neuronal cells from death and apoptosis in
several neurodegenerative diseases (19, 20).
Zizyphus species (Rhamnaceae) are broadly used as
herbal medicines in different parts of the world,
particularly in Asia, for the treatment of various
acute and chronic diseases (21). The ZJF has been
defined as the ‘fruit of life’, as it is an excellent source
of vital functional components such as flavonoids,
polyphenols, polysaccharides and saponins that are
responsible for different biological activities
including antitumor activity, improvement of central
nervous system complaint, regulation of immune
function, pain relief and decrease of blood glucose
and triglyceride (12, 22-26).
Previous studies have shown that caffeic acid, p-
coumaric acid, ferrulic acid and p-hydroxybenzoic
acid have the highest amount of phenolic
components in Ziziphus that are responsible for the
considerable antioxidant activity (27, 28). As
mentioned before, our results revealed that
hyperglycaemia leads to a significant increase in
caspase-3 activation (as a main biochemical factor of
apoptosis), and the ZJF extract had a suppressing
effect on its activation and eventually prevented high
glucose-induced apoptosis in PC12 (Figure 5). In
addition, several studies show that some natural
extracts suppress high glucose-induced neuronal cell
dysfunction complications (such as diabetic
neuropathy) through apoptosis inhibition (14, 29,
30). Among the various natural antioxidants in
Ziziphus, caffeic acid and ferrulic acid were reported
as potent anti-apoptotic flavonoid compounds (31).
Additionally, caffeic acid prevents protein tyrosine
kinase, lipoxygenase and cyclooxygenase activities
(32-34). Some studies show that caffeic acid can
block/reduce the activation of tumour necrosis
factor-alpha (TNF-α) (35). In addition, TNF-α
activates nuclear factor kappa B (NF-κB) (36, 37),
which exists in neurons (8, 34). NF-κB activation has
been implicated as an important regulator of genes
that control apoptosis. Therefore, caffeic acid (one of
the main components of Z. jujuba) can prevent
apoptosis induced by hyperglycaemic conditions.
Normally, the generation of ROS and other free
radicals are controlled by several innate scavenger
molecules, which are typically found in the cell and
quench free radicals. Antioxidant enzymes such as
Kaeidi et al Zizyphus jujuba attenuates neurotoxicity
Iran J Basic Med Sci, Vol. 18, No. 3, Mar 2015
305
superoxide dismutase, glutathione peroxidase (GPx)
and several non-enzymatic free radical scavengers
are involved in the antioxidant defence mechanisms
(38). Our previous study demonstrated that the ZJF
extract increased GPx activity in the hippocampus of
ethanol-treated rats (12). With regard to this, the
Z. Jujuba extract may prevent hyperglycaemic
toxicity by elevating the intracellular antioxidant
system (such as GPx) and detoxify the generation of
the high glucose-induced mass of free radical and the
generation of apoptosis.
Conclusion
This study suggests that the aqueous extract of the
ZJF protects PC12 cells against high glucose-induced
toxicity. The mechanisms underlying these effects may
be due, at least in part, to reduced ROS generation and
apoptosis.
Acknowledgment
We are grateful to Headof the Department of Cell
Engineering and Cell Therapy at Tarbiat Moddares
University, Tehran, Iran for their experiment
equipment’s and technical assistance.
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... Luteolin has been shown to improve blood glucose, glycosylation, insulin, and HOMR-IR levels in diabetic model mice, with positive effects against diabetes and its complications [39]. Kaempferol has excellent antioxidant properties and can correct hyperglycemia in DM rats by regulating oxidative stress and reducing AGE accumulation, thus preventing the risk of complications [40,41]. It reduces the expression of IL-1β and TNF-α, thereby inhibiting the neuroimmune activation of microglia and alleviating the progression of diabetic neuropathy [42]. ...
... x z y (p) Figure 6: The docking model diagram of the active ingredient of the drug and the core target molecule: (a-d) the action mode of TP53 and quercetin, luteolin, kaempferol, and formononetin; (e-h) the action mode of STAT3 and quercetin, luteolin, kaempferol, and formononetin; (i-l) the action mode of MAPK1 and quercetin, luteolin, kaempferol, and formononetin; (m-p) the action mode of JUN and quercetin, luteolin, kaempferol, and formononetin. Activated the Nrf-2/HO-1 pathway, inhibited the NF-κB pathway, and inhibited iNOS, COX-2, IL-6, and TNF-α DRG cells [35] Upregulated Beclin-1 and LC3 protein expression levels, increased cell proliferation, and upregulated autophagy Schwann cells [36] Reduced total cholesterol and TBARS levels, increased HDL-cholesterol, SOD, CAT, and GSH-Px activity Db/db mice [37] Luteolin Upregulated protein levels of Nrf2 and HO-1, improved nerve conduction velocity and nerve blood flow Diabetic rats [38] Improved the levels of blood glucose, HbA 1c, insulin, and HOMR-IR KK-A y mice [39] Reduced mRNA expression of SREBP-1c, TNF-α Kaempferol Regulated oxidative and nitrosative stress and reduced the formation of AGEs Diabetic rats [40] Reduced ROS production and inhibited caspase-3 activation PC12 cells [41] Reduction IL-1β, TNF-α, IC, and ROS and inhibited neuroimmune activation of microglia Diabetic mice [42] Formononetin Inhibited islet B cell apoptosis and promoted islet B cell regeneration, insulin secretion, hepatic glycogen synthesis, and hepatic glycolysis Diabetic mice [43] Controlled hyperglycemia and increased expression of SIRT1 and NGF Diabetic rats [44] Increased SIRT1 expression and reduced blood glucose Diabetic rats [45] 12 Journal of Diabetes Research and activator of transcription 3, a member of the signal transducer and activator of transcription family, is closely associated with central cell growth, proliferation and survival, and immune response [56]. Activated STAT3 can be implicated in the activity of downstream mediators such as p27kip1, P16INK4A, and p21kip1 proteins, which regulate cell growth, differentiation, and angiogenesis and are involved in the pathogenesis of diabetes [57]. ...
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Objective. To investigate the potential mechanism of action of Yi-Qi-Huo-Xue-Tong-Luo formula (YQHXTLF) in the treatment of diabetic peripheral neuropathy (DPN). Methods. Network pharmacology and molecular docking techniques were used in this study. Firstly, the active ingredients and the corresponding targets of YQHXTLF were retrieved using the Traditional Chinese Medicine Systems Pharmacology (TCMSP) platform; subsequently, the targets related to DPN were retrieved using GeneCards, Online Mendelian Inheritance in Man (OMIM), Pharmgkb, Therapeutic Target Database (TTD) and Drugbank databases; the common targets of YQHXTLF and DPN were obtained by Venn diagram; afterwards, the “YQHXTLF Pharmacodynamic Component-DPN Target” regulatory network was visualized using Cytoscape 3.6.1 software, and Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed on the potential targets using R 3.6.3 software. Finally, molecular docking of the main chemical components in the PPI network with the core targets was verified by Autodock Vina software. Results. A total of 86 active ingredients and 229 targets in YQHXTLF were screened, and 81 active ingredients and 110 targets were identified to be closely related to diabetic peripheral neuropathy disease. PPI network mapping identified TP53, MAPK1, JUN, and STAT3 as possible core targets. KEGG pathway analysis showed that these targets are mostly involved in AGE-RAGE signaling pathway in diabetic complications, TNF signaling pathway, and MAPK signaling pathway. The molecular docking results showed that the main chemical components of YQHXTLF have a stable binding activity to the core pivotal targets. Conclusion. YQHXTLF may act on TP53, MAPK1, JUN, and STAT3 to regulate inflammatory response, apoptosis, or proliferation as a molecular mechanism for the treatment of diabetic peripheral neuropathy, reflecting its multitarget and multipathway action, and providing new ideas to further uncover its pharmacological basis and mechanism of action. 1. Introduction Diabetic peripheral neuropathy (DPN) is one of the most common and serious microvascular complications of diabetes which is characterized by pain, sensory abnormalities, and loss of sensation [1, 2]. It has been shown that DPN affects approximately 40% to 60% of people with diabetes [3], and if not well treated, it increases the risk of disability and mortality [4]. Currently, there is no specific treatment for DPN in modern medicine, which consists mainly of improving metabolic disorders and pain management [5, 6]. With the continuous improvement in medical care and the increasing demand for health, the main issue facing us today is how to prevent and control the progression of DPN and improve the quality of survival of patients. Traditional Chinese Medicine (TCM) has a long history of treating diabetes mellitus and its complications [7, 8]. In TCM, DPN is often classified as “paralysis,” “impotence,” and “blood paralysis” [9]. It is often caused by prolonged thirst, depletion of Qi and blood, deficiency of both yin and yang, and loss of nourishment for the tendons and veins, resulting in coldness, numbness, and muscle atrophy [10, 11]. Treatment is mostly based on benefiting Qi and nourishing Yin, invigorating blood circulation and relieving pain, emphasizing the treatment of both the symptoms and the root cause, and overall regulation [12]. A large number of studies have shown that Chinese medicine is effective in treating DPN, significantly improving the clinical symptoms of patients and delaying the development of the disease, with few toxic side effects [13]. Therefore, exploring the regulatory mechanisms of TCM can help develop new therapeutic approaches to improve the treatment of DPN. Yi-Qi-Huo-Xue-Tong-Luo formula (YQHXTLF) is an in-hospital preparation for the prevention and control of diabetic peripheral neuropathy at Anhui Provincial Hospital of Traditional Chinese Medicine. It consists of 7 Chinese herbal medicines: Astragalus (Huangqi), Radix Angelicae Sinensis (Danggui), Radix et Rhizoma Dioscoreae (Dihuang), Radix et Rhizoma Yanhusuo (Yanhusuo), Radix et Rhizoma Puerariae (Gegen), Radix et Rhizoma Chrysanthemum (Jixueteng), and Radix et Rhizoma Weilingensis (Weilingxian). The combination of all the herbs in this formula can treat both the symptoms and the root cause of pain by treating Qi and blood together, which can benefit Qi and invigorate blood, as well as promote circulation and relieve pain. Preliminary clinical studies have shown that this formula can alleviate abnormal skin sensation, numbness, and tingling in the limbs and improve motor nerve conduction speed and sensory nerve conduction speed in DPN patients [14]. Basic research found that this formula can reduce islet cell damage in db/db mice, improve blood flow in the sciatic nerve area, and promote the repair and regeneration of damaged nerves, and the mechanism of action may be related to the improvement of diabetic inflammatory lesions and inhibition of excessive activation of the MAPK signaling pathway [15]. However, due to the multicomponent and multitarget nature of the Chinese medicine formula, the exact mechanism of action of the formula is still unclear. Network pharmacology is a new discipline involving the analysis of drug-target-disease network associations [16]. It provides a systematic approach to the analysis of complex drug mechanisms of action and potential disease interventions by identifying the core targets shared by drugs and diseases [17, 18]. Through the use of network pharmacology, we can not only explore the complex active molecular components and potential molecular targets in Chinese medicine formulations but also understand the molecular relationships between different components in a compound formula and between the components and complex diseases and extract possible pathways for drug interventions to target diseases [19]. With the rapid development of network pharmacology, the mechanisms of TCM in the treatment of many serious diseases have been successfully predicted, and the multitarget integrated prevention and treatment approach has been applied to cancer [20], arthritis [21], diabetes, and other diseases with certain results [22, 23]. In this study, we use network pharmacology as a tool to further analyze the possible targets, molecular mechanisms, biological processes, and pathways of YQHXTLF for the treatment of DPN. We modeled the interrelationship between the targets of DPN and elucidated the synergistic mechanism between the active components of Chinese medicine, providing insights into the interrelationship and changes between Chinese medicine and diseases from the perspective of biological networks, which provided new possibilities and directions for the treatment of DPN. The flow chart of this study is shown in Figure 1.
... Recent studies on Z. jujuba revealed anxiolytic and sedative effects , as well as hepatoprotective actions (Peng et al. 2000). Other findings showed that the fruits of Z. jujuba possess neuroprotective ) and anti-inflammatory properties (Kaeidi et al. 2015). The aqueous extract of Z. jujuba leaves was demonstrated to exhibit antioxidant (Hovaneţ et al. 2016) and antiinflammatory properties (Damiano et al. 2017). ...
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Pharmacological treatments against Alzheimer disease provide only symptomatic relief and are associated with numerous side effects. Previous studies showed that a concoction of Ziziphus jujuba leaves possesses anti-amnesic effects in scopolamine-treated rats. More recently, an aqueous macerate of Z. jujuba leaves has been shown to reduce short-term memory impairment in D-galactose-treated rats. However, no study on the effect of an aqueous macerate of Z. jujuba on long-term memory impairment was performed. Therefore, this study evaluates the effect of an aqueous macerate of Z. jujuba on long-term spatial memory impairment in D-galactose-treated rats. Long-term spatial memory impairment was induced in rats by administering D-galactose (350 mg/kg/day, s.c.), once dailyfor 21 days. On the 22nd day, the integrity of this memory was assessed using the Morris water maze task. Rats that developed memory impairment were treated with tacrine (10 mg/kg, p.o.), or aspirin (20 mg/kg, p.o.), or extract (41.5, 83, and 166 mg/kg, p.o.), once daily, for 14 days. At the end of the treatment, memory impairment was once more assessed using the same paradigm. Animals were then euthanized, and some pro-inflammatory cytokine markers were analyzed in the hippocampus or blood. The extract at all doses significantly reduced the latency to attain the platforming of the water maze test. The extract (83 mg/kg) also increased the time spent in the target quadrant during the retention phase. The extract markedly reduced the concentration of pro-inflammatory cytokine markers in the hippocampus and blood. Together, these results suggest that this aqueous extract Z. jujuba reduces long-term spatial memory impairment. This effect may be mediated in part by its anti-inflammatory activity.
... Similar results were previously obtained for whole-fruit extracts of Z. mistol [32]. Although there are no reports on the genotoxicity of Z. mistol seed, pulp, and skin extracts, studies indicate the absence of toxicity for Z. jujuba extracts on the DNA of cells such as lymphocytes, PC12 cells, and HepG2 cells [42][43][44]. Additionally, the acute toxicity of mistol PEE, using brine shrimp larvae as an organism model, was evaluated. Acute toxicity tested through the Artemia salina has been used for decades as a rapid and simple detection method on a laboratory scale due to its good correlation with animal models [45]. ...
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Background: The Ziziphus mistol fruit (vulgar name mistol) is used in northwestern Argentina in traditional food and beverage preparations and popular medicines for liver and respiratory disorders. Aims: The aim of this research was to evaluate the hypoglycemic and anti-inflammatory activity in pulp powders and sub-products (skin and seeds) of mistol fruit, along with their toxicity. Methods: Powders from mistol seeds, pulp, and skin were obtained. Antioxidant capacity and inhibitory activity against key enzymes involved in metabolic syndrome were determined by in vitro assays. Results: The mistol powders obtained from the different fruit parts reduced glucose bioaccessibility. Before and after simulated gastroduodenal digestion, the polyphenol-enriched extracts (PEE) obtained from mistol powders increased glucose uptake by yeast cells and inhibited the pivotal enzymes of the inflammatory pathway (cyclooxygenase-2, lipooxygenase-1, and phospholipase A2). The analyzed mistol powders did not show acute toxicity or genotoxicity in model organisms and cell cultures. Conclusions: These results evince the potentiality of both the pulp from Z. mistol fruits and residual biomass (seeds and skin) to obtain biofunctional powders to use as supplements for metabolic disorders associated with chronic diseases.
... Z. Jujuba traditionally is considered as a good remedy for controlling infection, fever and cough. Recent studies confirmed the anti-viral, immunomodulatory, anti-inflammatory, and neuroprotective effects of this medicinal plant [21][22][23][24]. The other herb is C. ...
Article
Background With the pandemic of coronavirus disease 2019 (COVID-19), and the growing attention of people around the world to the use of traditional and complementary medicines to control the disease, evaluating the effectiveness of these treatments has received special attention. Aim This study aimed to assess the clinical efficacy of a barley-based remedy combined with conventional medicine in comparison to the conventional therapy in confirmed COVID-19 patients. Materials and methods Seventy COVID-19 patients were randomly divided into barley-based remedy plus conventional medicine (barley-based remedy group) and conventional therapy (control group). Both groups were treated for 5 days. The outcomes were O2 saturation, main symptoms (fever, respiratory rate, cough, and fatigue), and laboratory data (lymphocytic count, and CRP); they were measured for 6 days. Results In comparison to the control group, the O2 saturation level in the barley-based remedy group significantly increased, from the second day of the intervention (P < 0.05). The herbal remedy significantly improved fatigue from the third day (P < 0.05). Meanwhile, the severity and frequency of cough between the groups were not significantly different. The herbal remedy had no significant effect on the CRP and the lymphocytic count of every time points of measurement. The average of respiratory rate and temperature of patients were in the normal range in both groups during the intervention. Conclusion Barley-based remedy could significantly enhance the blood O2 saturation and reduce fatigue. However, it needs to be confirmed by large sample size trials.
... A study detected a total of 18 amino acids in four jujube cultivars ("Hupingzao," "Huizao," "Xiaozao," and "Junzao") grown in northwest China. Proline (Pro), aspartic acid (Asp), and glutamic acid (Glu) accounted for 64.5%-70.0% of the total amino acids (Kaeidi et al., 2015). These amino acids have about 76.5% -80.8% of the antioxidant and anti-inflammatory properties of the total amino acids. ...
Article
Jujube (Ziziphus jujuba Mill.), a highly nutritious and functional fruit, is reported to have various health benefits and has been extensively planted worldwide, especially in China. Many studies have shown that bioactive components derived from jujube fruit have significant nutritional and potential biological effects. In this paper, the latest progress in research on major bioactive compounds obtained from jujube is reviewed, and the potential biological functions of jujube fruit resources are discussed. As a dietary supplement, jujube fruit is well recognized as a healthy food which contains a variety of bioactive substances, such as polysaccharides, polyphenols, amino acids, nucleotides, fatty acids, dietary fiber, alkaloids, and other nutrients. These nutrients and non-nutritive phytochemicals obtained from jujube fruit have physiological functions including anticancer, antioxidant, anti-inflammatory, anti-hyperlipidemic, anti-hyperglycemic, immunoregulatory, neuroprotective, sedative, and antiviral functions. Of note is that new constituents, including alkaloids, dietary fiber, and other bioactive substances, as well as the antiviral, hypoglycemic, lipid-lowering, and neuroprotective effects of jujube fruit, are systematically reviewed here for the first time. Meanwhile, problems affecting the exploitation of jujube fruit resources are discussed and further research directions proposed. Therefore, this review provides a useful bibliography for the future development of jujube-based products and the utilization of jujube nutritional components in functional foods.
... ese abundant bioactive compounds may account for the pharmacological properties of the plant [30][31][32]. e ethanolic extract of Z. jujuba has been shown nontoxic [22,24]. Despite the interesting reports on the beneficial effects in ameliorating several disorders as highlighted, there is, currently, no report on the antiamnesic effect of the aqueous extract of Z. jujuba. ...
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Alzheimer’s disease is a progressive cognitive dysfunction. However, pharmacological treatments are symptomatic and have many side effects, opening the opportunity to alternative medicine. This study investigated the antiamnesic effect of the aqueous extract of Ziziphus jujuba on D-galactose-induced working memory impairment in rats. Impairment of working memory was induced by subcutaneous (s.c.) injection of D-galactose (350 mg/kg/day) to rats for 21 days. These animals were then subjected to object recognition and Y-maze tests. Rats with confirmed memory impairment were treated per os (p.o.) with tacrine (10 mg/kg), aspirin (20 mg/kg, p.o.), extract (41.5, 83, and 166 mg/kg, p.o.), and distilled water (10 mL/kg, p.o.) daily for 14 days. At the end of the treatments, alteration in working memory was assessed using the above paradigms. Afterward, these animals were euthanized, and cholinergic, proinflammatory, and neuronal damage markers were analyzed in the prefrontal cortex. Rats administered D-galactose and treated with distilled water had impaired working memory (evidenced by decreased time spent on the novel object and discrimination index) and decreased spontaneous alternation in the Y-maze. D-galactose also decreased the levels of acetylcholinesterase and acetylcholine and increased the level of glial fibrillary acidic protein, ionized calcium-binding adapter molecule 1, tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1β), interleukin 6 (IL-6), and interferon-gamma (IFN-γ). Treatment with the extract (166 mg/kg) reversed the time spent on the novel object and the discrimination index. It equally increased the percentage of spontaneous alternation. Neurochemical analysis revealed that the extract markedly alleviated acetylcholinesterase activity and neuroinflammation. These observations were corroborated by the reduction in neuronal loss. Taken together, these results suggest that Ziziphus jujuba aqueous extract possesses an antiamnesic effect. This effect seems to involve cholinergic and anti-inflammatory modulations. This, therefore, claims using this plant in the treatment of dementia in Cameroon subject to further studies and trials. 1. Introduction Alzheimer’s disease (AD) is the most common form of dementia in the aging population. This condition is associated with progressive degeneration of thinking and memory [1]. This condition affects the cerebral cortex and hippocampus and leads to progressive degeneration in brain function. AD is estimated to affect over 44 million people worldwide [2, 3]. According to the WHO, the number of people affected by this disease is expected to double every 20 years, from 65.7 million in 2030 to 115.4 million in 2050 [4, 5]. The risk factors for AD include aging, hypertension, obesity, stroke, obesity, and diabetes. Despite the enormous research on AD and its etiology, the exact molecular mechanisms underlying AD remain unclear [6]. Nonetheless, research in animals and humans suggests that the central degeneration characteristic of AD can be classified into three categories: neurofibrillary pathology, deposits of amyloprotein beta peptide, and loss of cholinergic neurons in the hippocampus [7]. Furthermore, AD is linked in part to a deficiency in the brain neurotransmitter, acetylcholine, and the inhibition of acetylcholinesterase (AchE) is important for the treatment of AD. Several scientific findings implicate other pathways such as oxidative stress, excitotoxicity, apoptosis, and neuroinflammation in the pathophysiology of AD [8]. This latter can be modeled in rodents by the systemic administration of certain chemicals such as scopolamine or D-galactose. D-galactose is a monosaccharide sugar found in dairy products, avocados, sugar beets, and mucilages; it is used as a model for senescence in age-related neurodegenerative diseases [9]. Accumulating evidence has shown that chronic systemic exposure of rodents to D-galactose leads to progressive neuronal loss and associated memory impairment [6]. These effects appear to be mediated through oxidative stress, neuroinflammation, among others and converge to lead to neurodegeneration [10]. To manage AD, many drugs are currently being used (Tacrine, Donepezil, Rivastigmine, Galanthamine, and Memantine) [11]. Unfortunately, these treatments are symptomatic and have many side effects including insomnia, anorexia, diarrhea, fatigue, nausea, gastrointestinal disorders, and cardiovascular disorders [12]. The plant products on the other have long been used in treating memory impairment. Ginkgo biloba, Catharanthus roseus, Bacopa monnieri, Acorus calamus, and Centella asiatica are some of the plants whose extracts are used in the herbal formulation as remedies for AD. Therefore, herbal remedies could potentially be a great source for the discovery of effective and safe drugs against AD. According to the WHO, herbal medicine has become a major component of primary health care [13]. Ziziphus jujuba, which is the subject of the present study, is a plant of the Rhamnaceae family, used in Asia and African traditional medicines to treat asthma, sleep disorders, obesity, gastrointestinal disorders, urinary disorders, and neurodegenerative diseases [14, 15]. In Cameroon, according to the claims of traditional healers, the fruits are used to treat ear infections, rickets, and anorexia [16, 17]. Also, the seeds are used as dewormers, while the leaves are used to treat mental disorders [16, 17]. In recent years, Z. jujuba has been shown to exert nephroprotective [18], hepatoprotective [18], anxiolytic, antioxidant, and sedative effects [19, 20]. The fruit of Z. jujuba was shown to possess anti-inflammatory [21] and neuroprotective [22] activities. Besides, the leaves of Z. jujuba were shown to possess anti-inflammatory and antioxidant properties [23, 24]. Neuropharmacological studies showed that the ethanolic extract of the seeds improves cognitive dysfunction in experimental models of AD in rats [25, 26] and ameliorates seizures and cognition in experimental models of seizures in rats [27]. Phytochemical analysis by high-performance liquid chromatography indicates the presence of (‒)-catechin, quercetin-3-O-robinobioside, rutin, chlorogenic acid, caffeic acid, ferulic acid, ellagic acid, epicatechin, and quercetin-3-O-α-L-arabinosyl-(1⟶2)-α-L-rhamnoside in the leaves of Z. jujuba [28–30]. These abundant bioactive compounds may account for the pharmacological properties of the plant [30–32]. The ethanolic extract of Z. jujuba has been shown nontoxic [22, 24]. Despite the interesting reports on the beneficial effects in ameliorating several disorders as highlighted, there is, currently, no report on the antiamnesic effect of the aqueous extract of Z. jujuba. Therefore, this study aimed to examine the antiamnesic effect of the aqueous extract of Z. jujuba on memory impairment induced by D-galactose in rats. The involvement of cholinergic and anti-inflammatory pathways was also explored. 2. Materials and Methods 2.1. Plant Material and Extract Preparation The leaves of Z. jujuba used in this study were harvested in Mora (Far-North region, Cameroon), in November 2018. The whole plant was identified at the National Herbarium of Cameroon (Yaoundé) by Mr. Ngansop Tchatchouang Eric and compared to sample N°14446/HNC. To prepare the aqueous extract, the healer macerates two teaspoons (50 g) of leaf powder in 5 L of tap water for 72 h. Then, he filters the mixture and prescribes a full glass six-time daily to an adult of about 70 kg. This corresponds to a daily intake of approximately 3.6 L. In our laboratory, the extract of Z. jujuba was prepared mimicking the traditional healer’s method. Briefly, the leaves of Z. jujuba were washed, dried in the shade, and crushed. The resulting powder was macerated (50 g) in 5000 mL of distilled water for 72 h. In the end, the mixture was filtered using Whatman number 3, and the macerate (stock solution) was evaporated in an oven at 45°C. A stock solution was made from the dry extract (6 g), representing a 12% yield. Thus, the dose administered to an adult of about 70 kg was 13.45 mg/kg. To obtain the corresponding dose in rats, the dose above was multiplied by 6.17 (metabolism factor), giving an 83 mg/kg dose. Also, to achieve a dose-dependent effect, the stock solution was either diluted two times to a dose of 41.5 mg/kg and concentrated 2 times to a dose of 166 mg/kg. Therefore, solutions were administered per os (p.o.) to rats at doses of 41.5, 83, or 166 mg/kg. 2.2. Animals and Ethics 3-month-old male rats (Wistar), weighing between 150 and 250 g, were used for this study. These animals were acquired from a private animal house and acclimatized for 7 days at the Laboratory of Animal Physiology (University of Yaoundé I) and were kept 4 per cage (50 cm × 50 cm) under ambient temperature (26–28°C) and natural light/dark cycle. During the experiments, the rats had free access to food and tap water ad libitum. The study was carried out following the principles governing the use of laboratory animals by the national (No: FWA-IRB00001954) and international (NIH publication No: 8023, revised 1996) ethic committees. All efforts were made to reduce the number of animals used. 2.3. Chemicals Tacrine, acetylsalicylic acid (aspirin), D-galactose, and other chemicals or reagents were purchased from Sigma Chemical laboratories, St. Louis (USA), while ethyl ether was purchased from Cooper laboratory (France). The doses of aspirin (20 mg/kg) [31, 32] and tacrine (10 mg/kg) [33, 34] were determined based on previous laboratory findings and dose-response curve [35]. 2.4. Methods 2.4.1. Experimental Design and Induction of Memory Loss with D-Galactose The experimental rats were randomly divided into two groups as follows:(i)Group I (n = 7): rats received subcutaneously (s.c.) distilled water (10 mL/kg)(ii)Group II (n = 52): rats received D-galactose (350 mg/kg, s.c.) Rats in groups above were administered the corresponding substances once daily for 21 days. At the end of the treatments, the animals that received D-galactose were subjected to object recognition and Y-maze tests. Rats with memory loss were selected and divided into 6 groups of 7 rats each as follows:(i)D-galactose group received distilled water (10 mL/kg, p.o.)(ii)Test groups received Z. jujuba extract (41.5, 83, or 166 mg/kg, p.o.)(iii)Positive control groups received tacrine (10 mg/kg, p.o.) or aspirin (20 mg/kg, p.o.) The seventh group of mice (normal group) received distilled water (10 mL/kg, p.o.). These groups were treated once daily for 14 days. Three hours following the last treatment, the rats were subjected to object recognition and Y-maze tests. Afterward, they were euthanized and the prefrontal cortex was collected for the analysis of cholinergic and proinflammatory markers. Histological analysis of the prefrontal cortex was performed elsewhere (Figure 1).
... Recent studies have reported various biological activities of Zj, including antioxidant and anti-inflammatory functions [8,9]. It has been reported that Zj attenuates neurotoxicity induced by diabetic neuropathy in PC12 cells, indicating that Zj exerts a protective effect against neurotoxicity [10]. Zj contains several bioactive compounds such as polysaccharides, flavonoids, alkaloids, saponins and triterpenoids [6,11]. ...
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Backgroud/objectives: Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Due to the increased incidence of dementia, there is a corresponding increase concerning the importance of AD. In this study, we investigated the protective effects conferred by Zizyphus jujuba (Zj) and Zizyphus jujuba fermented by yeast (Zj-Y), on cognitive impairment in an AD mouse model. Materials/methods: AD was induced by injecting amyloid beta25-35 (Aβ25-35) in ICR mice, and subsequently 200 mg/kg Zj or Zj-Y was administered daily for 14 days. The cognitive ability of AD mice was observed through behavioral experiments in T-maze, novel object recognition, and Morris water maze tests. We subsequently measured the levels of malondialdehyde (MDA), nitric oxide (NO), aspartate aminotransferase, and alanine aminotransferase in either tissues or serum. Results: In behavioral tests, deterioration was revealed in the short- and long-term learning and memory functions in the Aβ25-35-injected control group compared to the normal group, indicating that Aβ25-35 injection impairs cognitive functions. However, administration of Zj and Zj-Y improved cognitive function in mice, as compared to the Aβ25-35-injected control mice. In addition, the Aβ25-35 induced elevations of MDA and NO in the brain, kidney, and liver were suppressed after exposure to Zj and Zj-Y. Especially, Zj-Y showed stronger scavenging effect against MDA and NO, as compared to Zj. Conclusions: Results of the present study indicate that Zj-Y exerts a protective effect on cognitive impairment and memory dysfunction, which is exerted by attenuating the oxidative stress induced by Aβ25-35.
... Seeds are used as dewormers [12] and leaves in cases of dementia [12]. In recent years, research on Z. jujuba fruits have shown to possesses anti-in ammatory [13] and neuroprotective activity [14], while the leaves showed to possess antiin ammatory [15], antifungal, anticancer, antifertility, antibacterial, anxiolytic, sedative, and antioxidant properties [16][17][18]. Research undertaken on the anti-amnesic effect of Z. jujuba revealed that the seed possesses a protective effect against spatial memory impairments in rats [19][20][21]. ...
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Background: Alzheimer's disease is a neurological condition that affects more than 44 million people worldwide. The available treatments target the symptoms rather than underlying causes. Ziziphus jujuba (Rhamnaceae) is used in traditional Cameroonian medicine to treat many disorders including memory impairments. The study aimed to evaluate the anti-amnesic and neuroprotective effects of Z. jujuba aqueous extract on scopolamine-induced memory disorders in rats. Methods: Learning and memory impairments were induced in rats by scopolamine (1mg/kg, i.p.) for 15 days. Rats that developed cognitive impairments were divided as follows: two positive control groups received piracetam (200 mg/kg, p.o.) or tacrine (1 mg/kg, p.o.); three test groups received the extract (29, 57, and 114 mg/kg, p.o., respectively) daily for 15 days. At the end of treatments, memory impairments were assessed by Morris water maze and Y-maze tests. Thereafter, animals were sacrificed and some biochemical parameters (oxidative stress, inflammation, and apoptosis) were estimated in the hippocampus and prefrontal cortex. Results: Z. jujuba decreased the time to reach the platform and increased the time in the target quadrant. However, it failed to affect spontaneous alternation in the Y-maze. Furthermore, the extract reversed scopolamine-induced oxidative stress, inflammation, and apoptosis. This was confirmed with the prevention of neuronal loss in the hippocampus or prefrontal cortex. Conclusions: These findings suggest that Z. jujuba extract possesses ant-amnesic and neuroprotective effects. It seems that these effects are mediated in part by antioxidant, anti-inflammatory, and anti-apoptotic activities. This, therefore, justify its use to treat dementia and psychiatric disorders in Cameroon’s folk medicine.
... Their research revealed the ability of ZJ in preventing ROS generation and neuronal apoptosis. Also, they concluded that ZJ could be used to ameliorate the management of diabetic neuropathy (Kaeidi et al. 2015). In addition, Ghaly et al. reported the scavenging effect of ZJ on free radicals generated by hydroquinone (Ghaly et al. 2008). ...
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All components of Ziziphus jujube (ZJ) were used in medicine and food in ancient Iran and China. Cisplatin is one of the most important drugs in the treatment of solid tumors. Taking this drug can result in nephrotoxicity through several mechanisms. The purpose of this study was to evaluate the effects of ZJ on the nephrotoxicity induced by cisplatin in rats. Thirty-five experimental rats were randomly divided into the following five groups (n = 7 per group) for an 8-day study: 1- Group C1 was the control group and received distilled water (1 ml/day); 2- Group C2 received a single dose of intraperitoneal cisplatin (5 mg/kg); 3- Group ZJ received 1500 mg/kg/day Ziziphus Jujube extract orally; 4- Group ZJ1 was given 1500 mg/kg/day of Ziziphus Jujube extract orally with taking a single dose of cisplatin (5 mg/kg) on the first day only; 5- Group ZJ2 received 3000 mg/kg/day of Ziziphus jujube extract orally with taking a single dose of cisplatin (5 mg/kg) on the first day only. Eventually, histopathological parameters, blood urea nitrogen (BUN), malondialdehyde (MDA), alanine transaminase (ALT), and aspartate transaminase (AST) were assessed. The findings showed that cisplatin administration resulted in severe degeneration in all parts of the nephron tubules. Also, the present study showed that MDA levels were significantly lower in both ZJ1 and ZJ2 groups compared with those in group C2 (p < 0.01). Moreover, the cisplatin-induced elevation of serum BUN levels significantly decreased in both ZJ1 and ZJ2 groups in comparison with that in group C2 (p < 0.01). In addition, serum levels of both ALT and AST were significantly higher in group C2 in comparison with those in group C1 (p < 0.05). Extensive tubular necrosis was seen in group C2. In brief, results of this research indicated that ZJ could prevent cisplatin-induced kidney injury in rats.
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Objective: To evaluate the effect of Ziziphus jujuba leaves extract in cafeteria diet and atherogenic diet induced obesity. Methods: Obesity was induced in albino rats by feeding cafeteria diet/atherogenic diet daily for 40 days in addition to normal diet ad libitum. Body weight was measured on day 1 and then on alternate days for 40 days. Daily food intake for group of 6 rats was assessed. Serum glucose and lipid levels and internal organs and fat pad weight analysis was carried out on day 41. Results: The Z. jujuba leaves extract treatment caused significant reduction in body weight, daily food intake, serum glucose and lipid levels, internal organs and fat pad weights in cafeteria and atherogenic diet fed rats when compared with control group of rats. Conclusion: The results of the present study conclude that alcoholic extract of Z. jujuba leaves showed anti-obese property by decreasing the body weight, food intake, serum glucose and lipid levels and internal organs and fat pad weights in dietary obese rats. The effect produced was comparable with that produced by standard anti-obese drug, Sibutramine.
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Objective: To study the effect of hydroalcoholic extract of Ziziphus jujuba leaves on neutrophil phagocytic function. Methods: The different concentrations (5, 10, 25, 50 and100μg/ml) of Ziziphus jujuba leaves extract was subjected, to study its effect on different in vitro methods of phagocytosis such as neutrophil locomotion and chemotaxis test, in vitro immunostimulant activity by slide method and qualitative nitro blue tetrazolium test using human neutrophils. Results: The Ziziphus jujuba leaves extract has stimulated chemotactic, phagocytic and intracellular killing potency of human neutrophils at the concentration range of 5-50μg/ml. Conclusion: The hydroalcoholic extract of Ziziphus jujuba leaves stimulates cell-mediated immune system by increasing neutrophil phagocytic function.
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The physico-chemical properties and antioxidant capacity of the five main jujube varieties: Junzao, Lingbaozao, Jinzao, Zanhuangzao and Lizao collected from loess plateau of China were determined. The analyzed components included fruit yield, moisture content, total mass per fruit, pH, titratable acidity (TA), reducing sugars, total sugars, total soluble solids (TSS), ascorbic acid, total phenolics content, total flavonoids content and several pure phenolic compounds. The output of the analyses showed higher amounts of ascorbic acid and phenolics in these jujube varieties than in some common fruits. The antioxidative capacity of the jujube extracts, evaluated with the reducing power, the β-carotene bleaching, the 2,2-diphenyl-1-picrylhydracyl (DPPH•), and the 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonicacid) (ABTS•+) scavenging methods, showed that the antioxidant activity of the extracts of Lingbaozao was excellent for free radical scavenging and a potent natural antioxidant of commercial value. Statistically significant differences were observed between jujube cultivars investigated with regards to the measured parameters except rutin content of fruit. These results demonstrated that the cultivar was the main factor which influences the physico-chemical properties and antioxidant activity of jujubes.
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Parkinson's disease is the most common progressive neurodegenerative disorder characterized by progressive death of midbrain dopaminergic neurons. Most neurodegenerative disease treatments are, at present, palliative.However, some natural herbal products have been shown to rescue neurons from death and apoptosis in some of neurodegenerative diseases. Not only the olive (Olea europaea L.) oil, but also the leaves have been used for medical purposes. Olive leaf extract (OLE) is being used by people as a drink across the world and as an integral ingredient in their desire to maintain and improve their health. Here, we investigated the effects of OLE and its main phenolic component, oleuropein, on 6-OHDA-induced toxicity in rat adrenal pheochromocytoma (PC12) cells as an in vitro model of Parkinson's disease. Cell damage was induced by 150 μM 6-OHDA and the cells survival rate was examined by MTT assay. Generation of intracellular reactive oxygen species (ROS) was studied using fluorescence spectrophotometry. Immunoblotting and DNA analysis were also employed to determine the levels of biochemical markers of apoptosis in the cells. The data showed that 6-OHDA could decrease the viability of the cells. In addition, intracellular ROS, activated caspase 3, Bax/Bcl-2 ratio as well as DNA fragmentation were significantly increased in 6-OHDA-treated cells. Incubation of cells with OLE (400 and 600 µg/ml) and oleuropein (20 and 25 µg/ml) could decrease cell damage and reduce biochemical markers of cell death. The results suggest that OLE and oleuropein have antioxidant protective effects against 6-OHDA-induced PC12 cell damage. The protective effects of OLE and oleuropein are correlative with their anti-oxidative and anti-apoptotic properties and suggest their therapeutic potential in the treatment of Parkinson's disease.
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Aims: The present study was undertaken to investigate the relationship between glyoxalase 1 (Glo1) enzyme activity and painful diabetic neuropathy (DN) in patients with diabetes mellitus. Methods: Glo1 activity and biochemical markers were determined in blood samples from 108 patients with type 1 diabetes, 109 patients with type 2 diabetes, and 132 individuals without diabetes as a control. Painful and painless peripheral DN was assessed and multivariate regression analysis was used to determine independent association of Glo1 activity with occurrence of painful DN. Results: In patients with type 1 and type 2 diabetes mellitus and painful DN compared to patients with painless DN, Glo1 activity was significantly reduced by 12 and 14%, respectively. The increase in Glo1 activity was significantly associated with reduced occurrence of painful DN after adjusting for confounders by multivariate analysis. Conclusions: Our results demonstrate for the first time that Glo1 activity is lower in patients with both types of diabetes mellitus who were diagnosed with painful DN. These data support the hypothesis that Glo1 activity modulates the phenotype of DN and warrant further investigation into the role of Glo1 in DN.
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In developing as well as developed countries, diabetes mellitus is one of the major problems. Oxidative stress plays a vital role in generation and maintenance of the diabetic neuropathy. The aim of present investigation was to study the effect of quercetin (10, 20 and 40 mg/kg; p.o.) in n-STZ-induced diabetic neuropathy in rats. Streptozotocin (90 mg/kg i.p.) was administered to rat pups of age 2 days (10-12 g), resultedin significant decrease in mechanical and thermal hyperalgesia, mechanical allodynia, motor and sensory nerve conduction velocity as well as superoxide dismutase, glutathione peroxidase along with membrane bound inorganic phosphate which was confirmed after 6 weeks of induction of diabetes. It caused enhanced hyperlipidemia, blood glucose level, glycated hemoglobin, oxidative-nitrosative stress, total calcium levels, inflammatory mediators (TNF-α and IL-1β levels) along with DNA damage. The 8-week treatment of quercetin (10, 20 and 40 mg/kg; p.o.) started 6 weeks after diabetes induction significantly improved nerve functions, biochemical as well as molecular parameters and DNA damage in sciatic nerve evidence in histological findings that were associated with n-STZ-induced diabetic neuropathic pain. Results of the present investigation suggest the neuroprotective effect of quercetin may be mediated through the inhibition of hyperglycemia and modulation of oxidative-nitrosative stress, pro-inflammatory cytokine (TNF-α and IL-1β) as well as DNA damage.
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The ripe edible fruits of jujube, Zizyphus jujuba Miller (syn. Z. sativa Gaertner, Z. vulgaris Lam.) and Christ's thorn jujube Zizyphus spina-christi (L.) Willd (Rhamnaceae family) were phytochemically investigated, comparing their quali-quantitative flavonoids profile. Twelve compounds from both methanol extracts have been recognized as quercetin, kaempferol, and phloretin derivatives by means of HPLC/ESI-MS analyses. Six major compounds have been purified by Sephadex LH-20 column chromatography followed by HPLC and were characterized using NMR spectroscopy. One C-glycoside, 3′,5′-di-C-β-d-glucosylphloretin, was detected in Z. spina-christi. The quantitative analysis of all compounds was also reported showing a higher content of flavonoids in Z. jujuba. © 2008 Elsevier Ltd. All rights reserved.
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The phenolic, alpha-tocopherol, beta-carotene and fatty acid composition of four jujube selections were investigated in this study. Phenolic compounds, alpha-tocopherol and beta-carotene were analyzed with an HPLC device equipped with a diode array detector, and the fatty acid methyl esters were analyzed with QP 5050 GC/MS equipped with a CP-Wax 52 CB column. Among the jujube selections, considerable differences in phenolic and fatty acid contents were found. Catechin, caffeic acid, p-coumaric acid, ferulic acid, rutin, apigenin-7-glucoside, eriodictyol, quercetin, p-hydroxybenzoic acid, chlorogenic acid and syringic acid were isolated from leaves. Rutin content was very high in the leaves of all the jujube selections, ranging from 269.0 to 367.90 mg/100 g, followed by apigenin-7-glucoside (22.90–49.38 mg/100 g) and eriodictyol (5.06–6.27 mg/100 g). Seven phenolic compounds, catechin, caffeic acid, epicatechin, ferulic acid, rutin, p-hydroxybenzoic acid and chlorogenic acid, were isolated from fruits of jujube selections. Catechin level ranged from 2.46 to 3.74 mg/100 g, and rutin level ranged from 0.88 to 3.60 mg/100 g for fruits. Predominant phenolics were rutin and apigenin-7-glucoside for leaves, and catechin and rutin for fruits. Jujube leaves contained higher amounts of phenolic compounds than jujube fruits. Alpha-tocopherol was only detected in fruits of selections 20-Ç-22 and 20-Ç-52 (0.04 and 0.07 mg/100 g, respectively). Beta-carotene was significantly higher in 20-Ç-22 (35.0 μg/100 g) than in the other selections. Lipid content of the fresh fruits ranged from 0.06% to 0.10% among the four jujube selections. The predominant fatty acids in all jujube selections were oleic acid, linoleic acid, palmitic acid and palmitoleic acid. Unsaturated fatty acids comprised 68.54–72.44% of the total fat in jujube fruit.