Improvement of Insulin Secretion and Pancreatic β-cell Function in Streptozotocin-induced Diabetic Rats Treated with Aloe vera Extract

Deciphering the ameliorative effect of Aloe vera (L.) burm. F. extract on histopathological alterations in Streptozotocin-induced WNIN/GR-ob rats

ETHNOPHARMACOLOGICAL RELEVANCE

Natural products have emerged as a novel source in the management of non-communicable diseases, more so in diabetes mellitus and its comorbidities. Aloe vera is widely recognized for its anti-hyperglycemic and anti-hyperlipidemic properties and numerous researchers have identified component (s) from Aloe vera attributing to these therapeutic effects.

AIM OF THE STUDY

The current work was undertaken to gain insight into the protective effect of Aloe vera (L.) Burm. f. extract to study the cytoarchitecture/histopathological alterations in the target organs in mutant Obese WNIN/GR-Ob rats that were made frank diabetic with streptozotocin.

MATERIALS AND METHODS

Rats were divided into five groups. 1)WNIN-GR-Ob/control group 2)WNIN-GR-Ob treated with STZ 3)WNIN-GR-Ob + STZ + Sitagliptin 4)WNIN-GR-Ob + STZ + Aloe vera 5)WNIN-GR-Ob/control group + Aloe vera. Histopathological analysis of the pancreas, kidney, liver, and adipocytes was done after 4 weeks of treatment.

RESULTS

The histopathological examination of STZ-induced diabetic rats revealed significant changes in all the vital organs including cell infiltration, degeneration, and necrosis. Treatment with A. vera negated most of the histopathological changes seen in STZ induced rats. Sitagliptin-which served as a positive control in the present study-reversed the alterations seen in streptozotocin rats.

CONCLUSION

Considering the hypoglycaemic and hypolipidemic activities of Aloe vera that have been previously demonstrated by us, the present study further re-instates the therapeutic efficacy of Aloe vera towards vital organs. It was able to restore islet cells and reduce β-cell damage. In addition, it was also able to aid in kidney tubular regeneration and reverse the degenerative changes brought on by streptozotocin on liver. Further, Aloe vera treated group exhibited moderate hyperplasia with decreased size of adipocytes and reduced macrophage infiltration. Thus, our findings advocate its application as an important nutraceutical in the therapeutic management of diabetes mellitus and associated complications.

Comprehensive review of opportunities and challenges of ethnomedicinal plants for managing type 2 diabetes

Diabetes mellitus is a prevalent metabolic disorder worldwide. A variety of antidiabetic medications have been developed to help manage blood glucose levels in diabetic patients, but adverse reactions and efficacy loss over time have spurred research into new therapeutic agents. In view of this, investigations into the antidiabetic effect of herbal products have been encouraged due to their potential availability, inexpensiveness, and relatively minimal side effects. This review explores the antidiabetic potentials of the eight most promising medicinal plants in terms of molecular mechanisms, phytochemistry, toxicology, and efficacy. These plant extracts have gone through clinical trials and demonstrated good control of blood glucose levels by increasing serum insulin levels, enhancing tissue glucose uptake, and/or decreasing intestinal glucose uptake. Yet, medicinal plants are far from being able to replace conventional antidiabetic drugs for patient management but they have the potential for further development if rigorous clinical trials on their mechanisms, delivery, and dose regimen are performed. To date, no study has been performed to isolate and characterize active compounds in these plant extracts, suggesting that further investigations in this area would be the next step to advance this field.

Chemical Characterization, Evaluation of Acute Oral Toxicity, and Anti-Diabetic Activity of Aloe sabaea Flowers Extract on Alloxan-Induced Diabetic Rats

The study aimed to conduct chemical profiling, acute in-vivo toxicity evaluation, and the potential anti-diabetic effect of standardized Aloe sabaea flowers ethanolic extracts (ASFEE) on alloxan-induced diabetic rats. The chemical composition was analyzed using GC-MS and TLC techniques. The oral acute toxicity study was performed according to the WHO 2000 and the OECD 420 guidelines. Furthermore, anti-diabetic activity was investigated using two doses of ASFEE (0.2 and 0.5 g/kg/day BW, p.o.) compared with glibenclamide (5 mg/kg/day, p.o.). A molecular docking investigation of the identified components with the PTPN9 enzyme was performed to figure out the proposed anti-diabetic mechanism. GC-MS analysis displayed the existence of 18 compounds; most of the compounds were fatty acids and their esters, and phytosterols. Total phenolic and flavonoid contents were 42.00±1.26 mg GAE/g DW and 22.21±1.55 mg QE/g DW, respectively. The results of the in-vivo toxicity study revealed the absence of noticeable signs of toxicity or mortality at various doses establishing the safety of the tested extract. The estimated LD50 value was higher than 10 g/kg. Antidiabetic action exhibited a noticeable decline in fasting blood glucose (FBG) levels comparable to glibenclamide with no inducing intense hypoglycemia and considerable excess weight.

Structural changes of thermally treated starch during digestion and the impact on postprandial glucose homeostasis

Intake of foods upon thermal treatment is typically associated with an elevated postprandial glycemic response, which is one of the risk factors for type 2 diabetes development and progression. In this study, rice starch was thermally treated using aqueous phase (boil), air phase (bake), and lipid phase (fry). Peak blood glucose levels in C57 mice increased by 16.94 %, 12.60 %, and 8.1 % after ingestion of thermally treated starch (20.23, 19.48, and 18.70 mmol/L), compared with raw starch (17.30 mmol/L). The insulin response to the intake of thermally treated starch increased (4.73 %-6.83 % higher than the control), whereas the concentration of GLP-1, a hormone used to promote insulin secretion, decreased (1.54 %-8.56 % lower than the control). Furthermore, thermally treated starch accelerated food absorption by enhancing gastrointestinal digestion, exacerbating postprandial glucose fluctuation at the next meal. Structural characterization showed thermal treatment reduced starch branching density and degree of structure order, which were not conducive to preventing the attack of enzymes. During digestion, they were highly hydrolyzed into low-molecular-weight fragments, and the proportion of ultrashort chains substantially increased. These findings provide a better understanding of the fine structure of starch that promotes hypoglycemia and initially explain how diets high in thermally treated starch impair glucose balance.

Nutraceutical management of metabolic syndrome as a palliative and a therapeutic to coronavirus disease (COVID) crisis

The global market for medicinal plants and herbs is on the increase due to their desirability, efficacy, and less adverse effects as complementary and alternative medications to the orthodox pharmaceuticals, perhaps due to their natural components and qualities. Metabolic syndromes are managed with changes in diet, exercise, lifestyle modifications and the use of pharmacological agents. Plants are now known to have potent antioxidant and cholinergic activities which are relevant to the management of several metabolic syndromes, which are unfortunately, co-morbidity factors in the coronavirus disease crisis. This review will focus on the biological activities of some plant products used as complementary and alternative medicines in the management of metabolic syndromes, and on their reported antiviral, antithrombotic, angiotensin-converting enzyme inhibitory properties, which are integral to their usage in the management of viral infections and may give an avenue for prophylactic and therapeutics especially in the absence of vaccines/formulated antiviral therapies.

Evaluation of acute oral toxicity, anti-diabetic and antioxidant effects of Aloe vera flowers extract

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe vera (L.) Burm.f. is widely used in various traditional systems of medicine worldwide. Since over 5000 years ago, several cultures have used A. vera extract medicinally for conditions ranging from diabetes to eczema. It has been shown to reduce the symptoms of diabetes by enhancing insulin secretion and protecting pancreatic islets.

AIM OF THE WORK

This research study aimed to investigate the in-vitro antioxidant effect, the acute oral toxicity, and the possible pharmacological in-vivo anti-diabetic activity with histological examination of the pancreas of the standardized deep red A. vera flowers methanolic extracts (AVFME).

MATERIALS AND METHODS

The liquid-liquid extraction procedure and TLC technique were used to investigate chemical composition. Total phenolics and flavonoids in AVFME were quantified by Folin-Ciocalteu and AlCl₃ colorimetric methods, respectively. The present study involved evaluating the in-vitro antioxidant effect of AVFME using ascorbic acid as the reference standard, an acute oral toxicity study by using thirty-six albino rats and different concentrations of AVFME (200 mg/kg, 2, 4, 8 and 10 g/kg b.w.). Furthermore, the in-vivo anti-diabetic study was performed on alloxan-induced diabetes in rats (120 mg/kg, I.P.) and two doses of AVFME (200 and 500 mg/kg b.w., orally) were used as compared to glibenclamide (5 mg/kg, orally) as a standard hypoglycemic sulfonylurea medication. A histological examination of the pancreas was performed.

RESULTS

AVFME resulted in the highest phenolic content of 150.44 ± 4.62 mg gallic acid equivalent per gram (GAE/g) along with flavonoid content of 70.38 ± 0.97 mg of quercetin equivalent per gram (QE/g). An in-vitro study revealed that the antioxidant effect of AVFME was strong as ascorbic acid. The results of the in-vivo studies showed that the AVFME didn't cause any apparent toxicity signs or death in all groups at different doses which proves the safety of this extract with a wide therapeutic index. The antidiabetic activity of AVFME demonstrated a considerable drop in blood glucose levels as glibenclamide, without severe hypoglycemia or significant weight gain which is considered an advantage of AVFME over glibenclamide use. The histopathological study of pancreatic tissues confirmed the protective effect of AVFME on the pancreatic beta-cells. The extract is proposed to have antidiabetic activity through inhibition of α-amylase, α-glucosidase, and dipeptidyl peptidase IV (DPP-IV). Molecular docking studies were conducted to understand possible molecular interactions with these enzymes.

CONCLUSION

AVFME represents a promising alternative source of active constituents against diabetes mellitus (DM) based on its oral safety, antioxidant, anti-hyperglycemic activities, and pancreatic protective effects. These data revealed the antihyperglycemic activity of AVFME is mediated by pancreatic protective effects while significantly enhancing insulin secretion through increasing functioning beta cells. This suggests that AVFME has the potential as a novel antidiabetic therapy or a dietary supplement for the treatment of type 2 diabetes (T2DM).

Insulin: A connection between pancreatic β cells and the hypothalamus

Insulin is a hormone secreted by pancreatic β cells. The concentration of glucose in circulation is proportional to the secretion of insulin by these cells. In target cells, insulin binds to its receptors and activates phosphatidylinositol-3-kinase/protein kinase B, inducing different mechanisms depending on the cell type. In the liver it activates the synthesis of glycogen, in adipose tissue and muscle it allows the capture of glucose, and in the hypothalamus, it regulates thermogenesis and appetite. Defects in insulin function [insulin resistance (IR)] are related to the development of neurodegenerative diseases in obese people. Furthermore, in obesity and diabetes, its role as an anorexigenic hormone in the hypothalamus is diminished during IR. Therefore, hyperphagia prevails, which aggravates hyper-glycemia and IR further, becoming a vicious circle in which the patient cannot regulate their need to eat. Uncontrolled calorie intake induces an increase in reactive oxygen species, overcoming cellular antioxidant defenses (oxidative stress). Reactive oxygen species activate stress-sensitive kinases, such as c-Jun N-terminal kinase and p38 mitogen-activated protein kinase, that induce phos-phorylation in serine residues in the insulin receptor, which blocks the insulin signaling pathway, continuing the mechanism of IR. The brain and pancreas are organs mainly affected by oxidative stress. The use of drugs that regulate food intake and improve glucose metabolism is the conventional therapy to improve the quality of life of these patients. Currently, the use of antioxidants that regulate oxidative stress has given good results because they reduce oxidative stress and inflammatory processes, and they also have fewer side effects than synthetic drugs.

Onopordum acanthium L. extract attenuates pancreatic β-Cells and cardiac inflammation in streptozocin-induced diabetic rats

BACKGROUND AND OBJECTIVE

Methanolic extract from Onopordum acanthium L. leaves (MEOAL) has been discovered to treat diabetic complications. The objective of this study is to evaluate the ameliorative role of MEOAL on pancreatic islet injury and myocardial inflammation in diabetic rats.

METHODS

Forty male Wister albino rats were allocated into five groups of eight rats each. Group A was the negative control group. Single intraperitoneal injection of streptozocin (50mg/kg) were used for the four experimental groups. Group B served as the positive control group. The rats in Groups C, D, and E received glibenclamide (5mg/kg), MEOAL (200, and 400 mg/kg) respectively, for eight weeks. Group C served as the standard drug group. High performance liquid chromatography (HPLC) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assays for antioxidant activity were conducted in MEOAL. In silico study, calculation of molecular binding energy (DG), and inhibition constant (pKi) of bioactive constituents in MEOAL were performed.

RESULTS

Administration of MEOAL significantly increases insulin content in β-cells with a marked enhancement of pancreatic islet structure, resulting in a significant reduction of blood glucose level and body weight loss. MEOAL treatment suppressed the increase of inflammatory cell score in myocardial tissue with an elevation of M2 -like macrophage. The phytochemical studies recorded the presence of six polyphenols, including catechin, kaempferol, syringic acid, p-coumaric acid, epicatechin and gallic acid in MEOAL. Moreover, the antioxidant activity of the extract was greater than that of standard ascorbic acid. The docking studies of the ligands Catechin, kaempferol and epicatechin with proteins showed high affinities with various targets related in β-Cells and cardiac inflammation.

CONCLUSIONS

The attenuation of pancreatic β-Cells damage and cardiac inflammation by MEOAL could be attributed to the presence of Catechin, kaempferol and epicatechin which have high affinities with the receptors namely pancreatic alpha-amylase, glucokinase, COX-2, and COX-1.

Apoptotic susceptibility of pancreatic alpha cells to environmentally relevant dose levels of bisphenol-A versus dibutyl phthalate is mediated by HSP60/caspase-3 expression in male albino rats

Unfortunately, humanity is exposed to mixed plasticizers such as bisphenol-A (BPA) and dibutyl phthalate (DBP) that are leached from the daily used plastic products. Previous studies have demonstrated their potential in pancreatic beta cell injury and diabetes induction. The study hypothesized that both compounds would affect the pancreatic alpha cells in albino rats when administered at environmentally relevant doses. Heat shock protein 60 (HSP60) and caspase-3 protein expression was also investigated as potential mechanisms. Thirty-six male Wistar albino rats were separated into four equal groups: control, BPA alone, DBP alone, and BPA + DBP combined groups. BPA and DBP were given in drinking water for 45 days in a dose of 4.5 and 0.8 µg/L, respectively. Fasting blood glucose, serum insulin, pancreatic tissue levels of malondialdehyde, and superoxide dismutase were measured. Pancreatic sections were subjected to hematoxylin & eosin (H & E) staining, glucagon, HSP60, and caspase-3 immunohistochemistry. Although all three experimental groups showed diffuse islet cell HSP60 immunoreactivity, rats exposed to BPA alone showed α-cell-only apoptosis, indicated by H & E changes and caspase-3 immunoreactivity, associated with reduced glucagon immunoreaction. However, rats exposed to DBP alone showed no changes in either α or β-cells. Both combined-exposed animals displayed α and β apoptotic changes associated with islet atrophy and reduced glucagon expression. In conclusion, the study suggested HSP60/caspase-3 interaction, caspase-3 activation, and initiation of apoptosis in α-cell only for BPA-alone exposure group, meanwhile DBP alone did not progress to apoptosis. Interestingly, both α/β cell effect was observed in the mixed group implying synergetic/additive action of both chemicals when combined.

Natural products for the treatment and management of diabetes mellitus in Zimbabwe-a review

Use of medicinal plants and herbs in the treatment and management of diseases, including diabetes mellitus and its complications remains an integral part of African tradition. In Zimbabwe, nearly one million people are living with diabetes mellitus. The prevalence of diabetes mellitus in Zimbabwe is increasing every year due to lifestyle changes, and has accelerated the use of traditional medicines for its treatment and management in urban areas. In addition, the high cost of modern medicine has led many people in rural parts of Zimbabwe to rely on herbal plant medicine for the treatment of diabetes mellitus and its complications. This review highlights a number of studies carried out to evaluate the antidiabetic properties of indigenous plants found in Zimbabwe with the goal of treating diabetes mellitus. Further, we discuss the mechanism of action of various plant extracts in the treatment and management of diabetes mellitus. Together, this review article can open pathways leading to discovery of new plant derived medicines and regularization of use of crude plant remedies to treat diabetes mellitus by the Zimbabwean government and others across Africa.

Exploring the plant-derived bioactive substances as antidiabetic agent: An extensive review

Diabetes mellitus (DM) is a metabolic syndrome. Diabetes has become more common in recent years. Chemically generated drugs are used to lessen the effects of DM and its following repercussions due to unpleasant side effects such as weight gain, gastrointestinal issues, and heart failure. On the other hand, medicinal plants could be a good source of anti-diabetic medications. This article aims to determine any plant matrix's positive potential. Food restriction, physical activity, and the use of antidiabetic plant-derived chemicals are all being promoted as effective ways to manage diabetes because they are less expensive and have fewer or no side effects. This review focuses on antidiabetic plants, along with their bioactive constituent, chemically characterization, and plant-based diets for diabetes management. There is minimal scientific data about the mechanism of action of the plant-based product has been found. The purpose of this article is to highlight anti-diabetic plants and plant-derived bioactive compounds that have anti-diabetic properties. It also provides researchers with data that may be used to build future strategies, such as identifying promising bioactive molecules to make diabetes management easier.

Aloe vera and Streptozotocin-Induced Diabetes Mellitus

Diabetes mellitus is defined as prolonged hyperglycemia, which can harm the eyes, kidneys, and cardiovascular and neurological systems. Herbal agents and their derived supplements have been used for treatment of diabetes mellitus as a part of integrated complementary medicine for centuries. Numerous studies have considered Aloe vera (L.) Burm.f, Xanthorrhoeaceae, as an alternative medicine due to its abundant bioactive chemicals, such as alkaloids, anthraquinones, and enthrones, with therapeutical properties including antioxidant, anti-inflammatory, neuro-protective, and anti-diabetic effects. Aloe vera has received considerable attention in traditional medicine for the treatment of several diseases including diabetes mellitus. Numerous studies have investigated the effects of herbal agents on diabetes mellitus using a streptozotocin-induced diabetic model. Thereby, this article reviews the effects of Aloe vera prescription on streptozotocin-induced diabetes mellitus to provide a clear insight into the role of this medicinal plant in several biological functions, such as antioxidant, wound healing, anti-inflammatory, anti-hyperglycemic, and anti-hyperlipidemic in diabetic models.

Aloe vera in diabetic dyslipidemia: Improving blood glucose and lipoprotein levels in pre-clinical and clinical studies

Dyslipidemia is a common feature of type 2 diabetes mellitus and is characterised by elevated triglyceride, decreased HDL cholesterol, and increased small dense LDL cholesterol levels. The underlying causes appears to be associated with insulin resistance, increased free fatty acid reflux, and low-grade inflammation, resulting in increased hepatic lipogenesis, and altered lipoprotein metabolism. Improved glycaemic control has been shown to have a positive effect on lipoprotein levels in diabetics. This can be achieved through medications/therapeutics and life style changes. Several classes of pharmacologic agents are currently in use to treat dyslipidemia. However, they may have dangerous long-term side effects, including an increased risk of liver dysfunction, weight gain, and cardiovascular diseases. Therefore, stronger alternatives with fewer side effects are required to reduce the diabetes associated complications. Many secondary plant metabolites have been shown to improve glucose homeostasis and lower lipid levels. Aloe vera and its constituents have long been used in a traditional medicine system for a diverse range of biological activities, including hypoglycaemic, antioxidant, anticarcinogenic, anti-inflammatory, and wound healing effects through various mechanisms and they have been covered well in literature. However, studies on the potential role of Aloe vera in the treatment of diabetic dyslipidemia are scanty. Therefore, in this systematic review, we focussed on the potential effect of Aloe vera and its active components in alleviating diabetic dyslipidemia, as well as their mechanism of action in pre-clinical and clinical studies.

The effects of oral Aloe vera on the efficacy of transplanted human endothelial cells and the expression of matrix metalloproteinases in diabetic wound healing

Background

Diabetic wounds are characterized by delayed healing and impaired angiogenesis. Aloe vera and human umbilical vein endothelial cells (HUVECs) are reported to facilitate wound healing, and the former also has hypoglycemic property. Matrix metalloproteinases are enzymes that play a role in diabetic wound pathogenesis.

Objective

To investigate whether oral Aloe vera can enhance the efficacy of HUVEC transplantation and inhibit the expression of matrix metalloproteinases in wound healing of diabetic mice.

Materials and methods

BALB/c nude mice were randomly assigned into five groups: normal control group, diabetic group (DM), DM transplanted with HUVECs, DM treated with oral Aloe vera, and DM treated with combined HUVECs and oral Aloe vera. Diabetes was induced by streptozotocin. Bilateral full-thickness excision cutaneous wounds were created. At days 7 and 14 post-wounding, the following parameters were determined: blood glucose, wound area, wound perfusion, capillary vascularity, re-epithelialization rate and tissue VEGF levels. Tissue expressions of MMP-2 and MMP-9 were compared between the DM mice and those treated with oral Aloe vera.

Results

Over days 7 and 14, Aloe vera exerted glucose-lowering effect in diabetic mice. Higher wound closure rate, blood flow and capillary vascularity, and lower MMP-2 and MMP-9 expressions were observed at both time points in DM treated with Aloe vera group compared with DM group (P < 0.05). Moreover, combined therapy of HUVECs and oral Aloe vera was more effective than Aloe vera or HUVECs alone in increasing VEGF levels, capillary vascularity and wound perfusion. Blood glucose levels were negatively correlated with angiogenesis (P = 0.000.

Conclusion

It is suggested that oral Aloe vera enhances the efficacy of HUVEC transplantation on diabetic wound angiogenesis, partly through improving glycemic control. Oral Aloe vera also promotes diabetic wound healing via inhibition of MMP-2 and MMP-9 expressions.

Aloe vera carbohydrates regulate glucose metabolism through improved glycogen synthesis and downregulation of hepatic gluconeogenesis in diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe vera (L.) Burm.f. is an ancient medicinal plant that belongs to the family Asphodelaceae. It has a rich source of bioactive constituents such as carbohydrates, polyphenols, peptides, sterols and tannins, etc. Aloe vera has multiple biological activities such as anti-inflammatory, antioxidant and antidiabetic activity etc. AIM OF THE STUDY: The present study investigated the antidiabetic mechanism of Aloe vera carbohydrate fraction (AVCF) and aimed to provide insights into the regulation of carbohydrate metabolism enzymes in glucose homeostasis.

MATERIALS AND METHODS

The antidiabetic effect of AVCF was evaluated using α-amylase, α-glucosidase inhibition, glucose diffusion and glucose uptake assay. The in vitro AVCF effect on insulin secretion, cell proliferation and inflammatory markers were determined using streptozotocin-induced oxidative stress on RIN-m5F cells. Streptozotocin-induced male Wistar diabetic rats were treated for 21 days with AVCF (54 mg/kg bw). The in vivo AVCF effect was measured on fasting plasma glucose, insulin, glucagon, hexokinase, glycogen synthase and glucose-6-phosphatase, levels in diabetic rats. Histopathological studies for organ-specific effects in the pancreas, liver and small intestine were also conducted.

RESULTS

AVCF-treated RIN-m5F cells significantly increased BrdU levels, with insulin secretion, and decreased TNF-α, IL-6 and nitric oxide levels. AVCF treated streptozotocin-induced diabetic rats showed significantly decreased fasting plasma glucose, glucagon and glucose-6-phosphatase levels with a concomitant increase in insulin, hexokinase, and glycogen synthase levels and, glycogen content. These findings corroborate with the improved hepatic glycogen content in the PAS stained histological section of the liver of AVCF treated diabetic rats.

CONCLUSION

These results suggest that CF of Aloe vera improved glucose metabolism by activation of glycogenesis and down-regulation of gluconeogenesis thereby, maintaining glucose homeostasis. Hence, AVCF can be used as an alternative medicine in the alleviation of diabetes mellitus symptoms.

Aloe vera and its two bioactive constituents in alleviation of diabetes -proteomic & mechanistic insights

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe barbadensis Miller, commonly known as Aloe vera has been used since time immemorial for treatment of various diseases such as cancer, inflammatory disorders, diabetes, wound healing etc. AIM: Diabetes mellitus is a complex disorder and understanding the molecular mechanisms involved is a key to identify different markers for early diagnosis of the disease. The proteomic approach offers a plethora of opportunities to identify markers and targets involved in pathogenesis of diabetes. The present study was undertaken to understand the mechanism of action of Aloe vera and its two constituents (Carbohydrates and Polypeptides) in the alleviation of diabetes in streptozotocin-induced diabetic rats through a proteomics approach.

METHODS

Different groups of rats were fed with Aloe vera extract, carbohydrate fraction and peptide/polypeptide fraction for three weeks. The diabetic rats fed with Aloe vera and its two fractions restored the glucose and insulin levels to normal. The plasma of the rats was depleted with IgG and albumin and proteomic analysis was carried out. Apolipoproteins (dyslipidemia), complement factors (inflammatory pathways), zonulin (intestinal permeability), anti-oxidant related proteins were selected in this study as these are involved in the progression of diabetes.

RESULTS

It was observed that Aloe vera extract is involved in the alleviation of diabetes through these pathways while the carbohydrate fraction alleviates diabetes through an anti-oxidant mechanism and glucose uptake while the polypeptide fraction alleviates diabetes through the restoration of intestinal permeability by reduced zonulin levels.

CONCLUSION

The constituents of Aloe vera works different pathways involved in diabetes and the synergistic effect of these constituents make Aloe vera extract a prospective candidate, which can alleviate diabetes through regulation of the pathways involved in the progression of diabetes.

Evaluation of pancreatic regeneration activity of Tephrosia purpurea leaves in rats with streptozotocin-induced diabetes

Background and aim

Flavonoid rich plant Tephrosia purpurea (T. purpurea), commonly known as Sarpunkha has been used in traditional systems of medicine to treat diabetes mellitus. However, its effectiveness in promoting regeneration of pancreas in diabetes has not been investigated. Therefore, the present study was undertaken to evaluate pancreatic β-cells regeneration, antioxidant and antihyperlipidemic potentials of T. purpurea leaves extract, its fractions and main constituent Rutin in diabetic rats.

Experimental procedure

The leaves extract and its fractions were first screened for acute and sub-chronic antidiabetic activity in a dose range of 250–500 mg/kg orally. Further, fractions with potent antidiabetic activity were screened for pancreatic β-cells regeneration activity using histopathological studies and morphometric analysis, which was followed by estimation of biochemical parameters.

Results and conclusion

The most significant antidiabetic, pancreatic regeneration and antihyperlipidemic activity was exhibited by n-butanol soluble fraction of ethanol extract at the dose level of 500 mg/kg. Histopathology revealed that treatment with this fraction improved the β-cell granulation of islets and prevented the β-cells damage which was further confirmed by morphometric analysis. Thus, the present study validated the traditional use of T. purpurea plant in the treatment of diabetes, which might be attributed to pancreatic β-cells regeneration potential of its active constituent Rutin.

Taxonomy (classification by EVISE)

Traditional Medicine; Metabolic Disorder; Experimental Design; Cell Regeneration and Histopathology.

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Polyphenol rich extract possesses potent in vitro antioxidant activity.

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Extract and its fractions are having pancreatic regeneration potential in STZ induced diabetic model.

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Histopathological study of the pancreas extract and fraction treated diabetic rats showed islets expansion and decreased fatty infiltrate of the islets.

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Study validates the use of plant in treatment of diabetes.

Herbal Medicines Targeting the Improved β-Cell Functions and β-Cell Regeneration for the Management of Diabetes Mellitus

There is an increasing trend of investigating natural bioactive compounds targeting pancreatic β-cells for the prevention/treatment of diabetes mellitus (DM). With the exploration of multiple mechanisms by which β-cells involve in the pathogenesis of DM, herbal medicines are gaining attention due to their multitasking ability as evidenced by traditional medicine practices. This review attempts to summarize herbal medicines with the potential for improvement of β-cell functions and regeneration as scientifically proven by in vivo/in vitro investigations. Furthermore, attempts have been made to identify the mechanisms of improving the function and regeneration of β-cells by herbal medicines. Relevant data published from January 2009 to March 2020 were collected by searching electronic databases "PubMed," "ScienceDirect," and "Google Scholar" and studied for this review. Single herbal extracts, polyherbal mixtures, and isolated compounds derived from approximately 110 medicinal plants belonging to 51 different plant families had been investigated in recent years and found to be targeting β-cells. Many herbal medicines showed improvement of β-cell function as observed through homeostatic model assessment-β-cell function (HOMA-β). Pancreatic β-cell regeneration as observed in histopathological and immunohistochemical studies in terms of increase of size and number of functional β-cells was also prominent. Increasing β-cell mass via expression of genes/proteins related to antiapoptotic actions and β-cell neogenesis/proliferation, increasing glucose-stimulated insulin secretion via activating glucose transporter-2 (GLUT-2) receptors, and/or increasing intracellular Ca2+ levels were observed upon treatment of some herbal medicines. Some herbal medicines acted on various insulin signaling pathways. Furthermore, many herbal medicines showed protective effects on β-cells via reduction of oxidative stress and inflammation. However, there are many unexplored avenues. Thus, further investigations are warranted in elucidating mechanisms of improving β-cell function and mass by herbal medicines, their structure-activity relationship (SAR), and toxicities of these herbal medicines.

Analysis of polyphenols in Aegle marmelos leaf and ameliorative efficacy against diabetic mice through restoration of antioxidant and anti-inflammatory status

The biomedical survey reports edible plant Aegle marmelos has been utilized for centuries by tribal communities in India as a dietary supplement for the management of diabetes. Herein, we have investigated cytotoxicity, cytoprotective and antidiabetic activity of characterized alkaloid-free hydroalcoholic extract of A. marmelos (AFEAM; 200 and 400 mg/kg). Identification of polyphenols and quantification of major compounds were done using UPLC-MS and HPTLC, respectively. AFEAM showed good cytocompatibility and cytoprotective potential against oxidative stress induced by hyperglycemia in HepG₂ cells. The AFEAM intake had significantly ameliorated the serum blood glucose level, state of dyslipidemia, level of pro-inflammatory markers (tumor necrosis factor-α, interleukin-6, and interleukin-1β), and antioxidant (superoxide dismutase, catalase, glutathione peroxidase, and malondialdehyde) status in diabetic mice. Histological examination of the treated groups showed amelioration of damaged pancreas, liver, and kidney tissues. Conclusively, AFEAM intake might be promising dietary supplements for prediabetics as well as an adjuvant to modern treatment in diabetics. PRACTICAL APPLICATIONS: Different reports have been published on Aegle marmelos but as per our understanding till date, no study has been reported on the amelioration of diabetes due to alkaloid free hydroalcoholic extract of A. marmelos /polyphenolic content in the animal model. The result of this study indicated that A. marmelos supplementation effectively ameliorates diabetes through the restoration of antioxidant and anti-inflammatory status. This study has collated sufficient scientific evidence for the dietary application of A. marmelos in society especially for prediabetics, however, it can also be used as an adjuvant to modern treatments in diabetics.

Evaluation of testicular glycogen storage, FGF21 and LDH expression and physiological parameters of sperm in hyperglycemic rats treated with hydroalcoholic extract of Securigera Securidaca seeds, and Glibenclamide

Structural and physiological changes in sperm and semen parameters reduce fertility in diabetic patients. Securigera Securidaca (S. Securidaca) seed is a herbal medicine with hypoglycemic, antioxidant, and anti-hypertensive effects. The question now is whether this herbal medicine improves fertility in diabetic males. The study aimed to evaluate the effects of hydroalcoholic extract of S. Securidaca seeds (HESS), glibenclamide and a combination of both on fertility in hyperglycemic rats by comparing histological and some biochemical changes in testicular tissue and sperm parameters. The treatment protocol included administration of three doses of HESS and one dose of glibenclamide, as well as treatment with both in diabetic Wistar diabetic rats and comparison of the results with untrated groups. The quality of the testicular tissue as well as histometric parameters and spermatogenesis indices were evaluated during histopathological examination. Epididymal sperm analysis including sperm motility, viability, abnormalities, maturity, and chromatin structure were studied. The effect of HESS on the expression of LDH and FGF21 genes and tissue levels of glycogen, lactate, and total antioxidant capacity in testicular tissue was investigated and compared with glibenclamide. HESS improved sperm parameters in diabetic rats but showed little restorative effect on damaged testicular tissue. In this regard, glibenclamide was more effective than the highest dose of HESS and its combination with HESS enhanced its effectiveness so that histological tissue characteristics and sperm parameters were were comparable to those of healthy rats. The expression level of testicular FGF21 gene increased in diabetic rats, which intensified after treatment with HESS as well as glibenclamide. The combination of HESS and glibenclamide restored the expression level of testicular LDH gene, as well as tissue storage of glycogen, lactate and LDH activity, and serum testosterone to the levels near healthy control. S. Securidaca seeds can be considered as an effective supplement in combination with hypoglycemic drugs to prevent infertility complications in diabetes.

Plantago major L. Extracts Reduce Blood Glucose in Streptozotocin-Induced Diabetic Mice

Plantago major L. (P. major L.) is a perennial plant belonging to the family Plantaginaceae. It has been used as a folk remedy for diabetes in Europe and Asia. However, the biologically active constituents responsible for the antidiabetic effects have not been reported. The objectives of this study aimed at determining the chemical components of Plantago major L. and evaluating the antidiabetic activity of the extracts using streptozotocin- (STZ-) induced diabetic mice. In this study, the Swiss mice were fed a high-fat diet to gain weight before STZ injections to induce diabetic conditions. The STZ-induced diabetic mice were orally treated with P. major L. extracts. The blood glucose test results from the treated diabetic mice and nontreated diabetic mice were compared. We found that a 15-day treatment with EP6 extract from P. major L. at a dose of 400 mg/kg could reduce the blood glucose level to the same level as a 15-day treatment with glucophage at a dose of 70 mg/kg. The major chemical components and structural characterization of EP6 extract were also reported. AST (aspartate transferase) and ALT (alanine aminotransferase) indicators of liver damage were measured in the treated and nontreated diabetic mice to give an overall view of the antidiabetic effect of P. major L. extracts.

Alleviation of diabetes mellitus through the restoration of β-cell function and lipid metabolism by Aloe vera (L.) Burm. f. extract in obesogenic WNIN/GR-Ob rats

ETHNOPHARMACOLOGICAL RELEVANCE

Aloe vera (L.) Burm. f. extract has been medicinally used for over 5000 years in different cultures for its curative and therapeutic properties ranging from dermatitis to diabetes. It has been demonstrated to alleviate diabetes through its protective effects on pancreatic islets and by improving insulin secretion.

AIM OF THE STUDY

To investigate the simultaneous effect of ethanolic A. vera gel extract on diabetes and obesogenic milieu in Streptozotocin-induced WNIN/GR-Ob mutant obese rats.

MATERIALS AND METHODS

A total of 30 rats were grouped equally into WNIN/GR-Ob control (received water as a vehicle), WNIN/GR-Ob Diabetic rats (Streptozotocin-35 mg/kg bw), WNIN/GR-Ob Diabetic rats + Sitagliptin (10 mg/kg bw), WNIN/GR-Ob Diabetic rats + A. vera (300 mg/kg bw) and GR-Ob control + A. vera (300 mg/kg bw). After 4 weeks of treatment, fasting blood glucose, serum insulin, Homeostatic Model Assessment - Insulin Resistance and β-cell function, glucose-stimulated insulin secretion, Dipeptidyl peptidase-IV activity, and lipid profiles were studied. In addition, ultrastructural analysis of isolated islets and dual-energy X-ray absorptiometry analysis for body composition were also carried out.

RESULTS

The A. vera treated group showed a significant reduction (p < 0.05) in triglyceride, Very low-density lipoprotein levels, Triglyceride to High-density lipoprotein ratio as well as fasting blood glucose levels and DPP-IV activity with a concomitant increase in the serum insulin levels. The increase in IR was observed in both WNIN/GR-Ob control and diabetic rats with a significant decrease in β-cell function in the diabetic rats as per Homeostatic Model Assessment values. Oral administration of A. vera was effective in both reducing Homeostatic Model Assessment-Insulin Resistance and increasing Homeostatic Model Assessment-β values. Also, the treated group demonstrated preservation of islets and a significant increase (p < 0.05) in the diameter of β-cell as evident through Scanning electron microscope analysis. The increase in lean body mass was manifested in the treated group with a reduction in Fat percent in comparison with other groups.

CONCLUSION

The beneficial effects of A. vera in WNIN/GR-Ob strain may be attributed to its ability to lower lipid profile thus improve insulin sensitivity and/or modulating β-cell function. Thus, it has great therapeutic potential as an herbal remedy for the treatment of diabetes and associated adverse effects such as obesity. The exact mechanism underlying the observation needs to be investigated further to explore the anti-obesity and anti-diabetic properties of A. vera and advocate its potential application as alternative medicine.

Role of zonulin and GLP-1/DPP-IV in alleviation of diabetes mellitus by peptide/polypeptide fraction of Aloe vera in streptozotocin- induced diabetic wistar rats

ETHNO-PHARMACOLOGICAL RELEVANCE

The genus Aloe has a long history of usage in medicine. Aloe barbadensis Miller, commonly known as Aloe vera, is said to possess anti-diabetic, anti-inflammatory, anti-cancer, anti-microbial, immunomodulation, wound healing properties.

AIM OF THE STUDY

In diabetes mellitus, loss in intestinal permeability is observed with high levels of zonulin and low levels of glucagon-like peptide-1 (GLP-1) leading to hyperglycemia. The aim of the study was to understand the role of peptide/polypeptide fraction (PPF) of Aloe vera in the alleviation of diabetes through maintaining the intestinal permeability by regulating the zonulin and GLP-1 levels.

MATERIALS AND METHODS

The PPF of Aloe vera was obtained through trichloroacetic acid precipitation. The anti-diabetic potential of the PPF was tested through DPP-IV inhibition, glucose diffusion assay, and by using Rin-m5F cells. The anti-diabetic potential of the PPF was tested at a dose of 0.450 mg/kg bw in vivo using streptozotocin-induced diabetic Wistar rats. The effect of PPF on fasting plasma glucose, insulin, glucagon, Zonulin, GLP-1, DPP-IV, levels were studied in diabetic rats. The histopathological studies of the pancreas, small intestine, and liver were carried out for organ-specific effects.

RESULTS

PPF has the ability to reduce fasting plasma glucose levels with concomitant increase in insulin levels in streptozotocin-induced diabetic rats. It was also observed that increase in GLP-1 levels with a decrease in DPP-IV and zonulin levels thereby mitigating the loss of intestinal permeability. These findings correlate with the small intestine's histopathological observation where the excessive proliferation of epithelium in the small intestine of diabetic rats was reduced after PPF treatment.

CONCLUSION

These results suggest that the PPF of Aloe vera alleviates diabetes through islet cell rejuvenation via GLP-1/DPP-IV pathway and thereby suggesting the usage of PPF as an alternate medicine for diabetes mellitus with the possibility to reduce the intestinal permeability and zonulin levels.

Clinical trials with plants in diabetes mellitus therapy: a systematic review

INTRODUCTION

The chronic metabolic disorder diabetes mellitus is a fast-growing global problem with huge social, health, and economic consequences, having one of the highest morbidities and mortality rates. Prolonged use of many available medications can produce undesirable side effects. Thus, plants appear as an important source of bioactive resources for the discovery of new treatments for diabetes.

AREAS COVERED

In this sense, this systematic review focused on clinical trials involving plants of National List of Medicinal Plants of Interest to the Unified Health System (RENISUS) (or compounds) with antidiabetic properties. We analyzed indexed studies in PubMed following the reporting guidelines of PRISMA.

EXPERT OPINION

Of the 51 clinical trials found, Curcuma longa, Glycine max, Zingiber officinale, Punica granatum, Aloe vera, Momordica charantia are the species with the greatest amount of clinical trials and the attenuation of insulin resistance, decreased fasting blood glucose and glycosylated hemoglobin levels are some of the main mechanisms by which these plants exert hypoglycemic effects. Thus, we speculate that the Clinical Pharmacology should explore the field of plant-based compounds that will keep concentrating the attention of researchers, and therefore, we gathered studies in advanced stages that highlight the role of plants in the diabetes therapy.

Dietary polyvinyl alcohol and alginate nanofibers ameliorate hyperglycemia by reducing insulin and glucose-metabolizing enzyme levels in rats with streptozotocin-induced diabetes

Background and Aim:

Dietary management and antidiabetic drugs are used as therapies for diabetic patients worldwide. Alginate nanofibers were developed as a digestible food product that provides sufficient calories. This study aimed to evaluate the effect of polyvinyl alcohol (PVA) and alginate nanofibers on weight gain, blood glucose levels, and insulin and other serum parameters in diabetic rats.

Materials and Methods:

A total of 24 male Wistar rats were divided into six groups: (C−) Control group, (C+) diabetic rats, (T1) diabetic rats + fasting treatment for 12 h, (T2) diabetic rats + nanofibers ad libitum, (T3) diabetic rats + metformin + nanofibers ad libitum, and (T4) diabetic rats + metformin. All groups were treated for 21 days. Weight gain was evaluated by comparing initial and final weights. Blood glucose levels were evaluated weekly. Serum parameters were also evaluated at the end of the study. All variables were analyzed statistically using analysis of variance followed by Tukey’s post hoc test (p<0.05).

Results:

The T2, T3, and T4 groups showed a significant increase in weight compared to that of the C+ and T1 groups. The T3 group had the lowest blood glucose level of all groups at the end of the study. In the serum evaluation, the T2 and T3 groups showed a significant decrease compared to the C+ group for the following variables: Alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyltransferase (GGT), creatinine, tumor necrosis factor-alpha (TNF-α), and interleukin-1β (IL-1β). In contrast, the T2 group showed a significant decrease compared to the T3 group for aspartate aminotransferase and insulin levels.

Conclusion:

PVA and alginate nanofibers can modulate obesity, reduce blood glucose levels, and reduce serum levels of insulin, ALT, ALP, GGT, creatinine, TNF-α, and IL-1β in diabetic rats.

Flavonoids in the Treatment of Diabetes: Clinical Outcomes and Mechanism to Ameliorate Blood Glucose Levels

BACKGROUND

For thousands of years, natural food products have been used as a medicine for treating diseases that affect the human body, including diabetes mellitus (DM). Lately, several investigations have been performed on the flavonoid derivatives of plant origin, and their biological activity has been extensively studied.

METHODS

Given our need to know more mechanisms for treating DM, we performed a thorough research review on treating diabetes mellitus based on flavonoids, their therapeutic potential, and biological action.

RESULTS

Flavonoids reduce complications in addition to their vital role as effective supplements for preventing diabetes mellitus by regulating glucose metabolism, lipid profile, liver enzyme activity, a protein kinase inhibitor, PPAR, and AMPK with NF-κB.

CONCLUSION

The articles that we reviewed showed the positive role of flavonoids, which in a certain way reduce diabetes, but their side effects still need to be studied further.This review is focused on describing the different types of dietary flavonoids along with their mechanisms of reducing blood glucose and enhancing insulin sensitivity, as well as their side effects.

Ethnobotanical study and phytochemical profiling of Heptapleurum hypoleucum leaf extract and evaluation of its antimicrobial activities against diarrhea-causing bacteria

Background

Due to the development of superbugs as a result of unprescribed and frequent use of antibiotics in recent years, an alternate form of medicine had to be introduced. In light of this global threat, researchers all over the world have been gravitating towards herbal medicines. In order to find out new ways of saving the planet using medicinal plants, ethnobotanical studies must be carried out. Concerning this, an ethnobotanical study has been done in this paper to identify potential medicinal plants in Rangamati, Bangladesh.

Results

For the ethnobotanical survey, randomized 104 people were interviewed and 62 different plant species were found to treat 19 different kinds of diseases and 84% of people reported to be completely recovered. Furthermore, among the 19 diseases found, the majority of them were common cold, abdominal pain or gastric, diarrhea, and dysentery. From the 62 different plant species, Heptapleurum hypoleucum, used for the treatment of diarrhea, was selected for conducting further studies due to its heavy use as reported by the tribal people. In this study, the aqueous, ethanol, and methanol extracts of Heptapleurum hypoleucum were subjected to microbial susceptibility assays using the agar well diffusion method. The test microorganisms were Salmonella typhi, Streptococcus pneumoniae, Staphylococcus aureus, Shigella flexneri, and Escherichia coli. Among these, the most susceptible organisms were Staphylococcus aureus (21 mm) and Salmonella typhi (19 mm) in the ethanolic extract. Also, the methanolic extract showed an inhibition zone of 13 mm against E. coli, which was more than that of the antibiotic’s (11 mm). Phytochemical screening of the plant revealed that it contains alkaloids, phenols, steroids, and flavonoids, but lacks saponins and tannins.

Conclusion

To combat the rising threat of antibiotic resistance, ethnoscience needs to be consolidated with modern biotechnological techniques to make the most use of the vast amount of natural resources. The findings of this study indicate that Heptapleurum hypoleucum, an ethnobotanical medicinal plant, has shown comparable antimicrobial activity with commercial antibiotics against several diarrhea-causing pathogens and also contains several medically important phytochemicals.

Sperm Proteomics Analysis of Diabetic Induced Male Rats as Influenced by Ficus carica Leaf Extract

Diabetes mellitus is shown to bring negative effects on male reproductive health due to long-term effects of insulin deficiency or resistance and increased oxidative stress. Ficus carica (FC), an herbal plant, known to have high antioxidant activity and antidiabetic properties, has been used traditionally to treat diabetes. The objective of this study is to determine the potential of the FC leaf extract in improving sperm quality of streptozotocin (STZ) induced diabetic male rats from proteomics perspective. A total of 20 male rats were divided into four groups; normal (nondiabetic rats), negative control (diabetic rats without treatment), positive control (diabetic rats treated with 300 mg/kg metformin), and FC group (diabetic rats treated with 400 mg/kg FC extract). The treatments were given via oral gavage for 21 consecutive days. The fasting blood glucose (FBG) level of FC treated group demonstrated a significant (p < 0.05) decrease compared to negative group after 21 days of treatment, as well as a significant (p < 0.05) increase in the sperm quality parameters compared to negative group. Sperm proteomics analysis on FC treated group also exhibited the increase of total protein expression especially the proteins related to fertility compared to negative group. In conclusion, this study clearly justified that FC extract has good potential as antihyperglycemic and profertility agent that may be beneficial for male diabetic patients who have fertility problems.

Effect of Caesalpinia bonduc Polyphenol Extract on Alloxan-Induced Diabetic Rats in Attenuating Hyperglycemia by Upregulating Insulin Secretion and Inhibiting JNK Signaling Pathway

Caesalpinia bonduc has been used in herbal medicines for the treatment of a wide range of diseases from decades. The present study has explored the remedial potential and underlying mechanism of polyphenol extract of Caesalpinia bonduc in alloxanized diabetic rats. HPLC/MS analysis confirmed the presence of phenolics in considerable concentrations in Caesalpinia bonduc extract. Administration of different doses (250 and 500 mg/kg) of CPP extract to hyperglycemic rats for 8 weeks restored blood and serum glucose, insulin, glycosylated hemoglobin, leptin, amylin, and carbohydrate metabolizing enzymes level towards normal compared to alloxanized diabetic group. The effect of CPP extract on various genes such as Pdx-1, Ins-1, ngn-3, GLUT-4, and IRS-1 in insulin signaling pathway and Traf-4, Traf-6, and Mapk-8 in MAPK downstream JNK cascade was examined through qRT-PCR to access the core molecular mechanism involved in CPP-induced recovery of diabetes. Results have revealed that CPP extract reduced oxidative stress in pancreatic β cells by restoring free radical scavenging potential, reducing the mRNA expression of Mapk-8, Traf-4, and Traf-6, and increasing the Pdx-1, Ins-1, ngn-3, GLUT-4, and IRS-1 expression ensuing regeneration of β cells and subsequent insulin release from pancreas. The results obtained in this study recommend that CPP extract may be a promising therapeutic restorative agent in the treatment of diabetes mellitus.

Pharmacological Update Properties of Aloe Vera and its Major Active Constituents

Aloe vera has been traditionally used to treat skin injuries (burns, cuts, insect bites, and eczemas) and digestive problems because its anti-inflammatory, antimicrobial, and wound healing properties. Research on this medicinal plant has been aimed at validating traditional uses and deepening the mechanism of action, identifying the compounds responsible for these activities. The most investigated active compounds are aloe-emodin, aloin, aloesin, emodin, and acemannan. Likewise, new actions have been investigated for Aloe vera and its active compounds. This review provides an overview of current pharmacological studies (in vitro, in vivo, and clinical trials), written in English during the last six years (2014–2019). In particular, new pharmacological data research has shown that most studies refer to anti-cancer action, skin and digestive protective activity, and antimicrobial properties. Most recent works are in vitro and in vivo. Clinical trials have been conducted just with Aloe vera, but not with isolated compounds; therefore, it would be interesting to study the clinical effect of relevant metabolites in different human conditions and pathologies. The promising results of these studies in basic research encourage a greater number of clinical trials to test the clinical application of Aloe vera and its main compounds, particularly on bone protection, cancer, and diabetes.

Effect of simulated microgravity on the antidiabetic properties of wheatgrass (Triticum aestivum) in streptozotocin-induced diabetic rats

Microgravity affects plant growth and content. A three-dimensional clinostat was used at 4 rotations/min to rotate the seeds of Triticum aestivum cultivar (Ammon) in three dimensions for 7 days, following which the antioxidant activities of ethanolic extracts were evaluated using both nitric oxide- and hydrogen peroxide-scavenging activities. The antidiabetic activities of ethanolic extracts were evaluated by measuring the concentration of plasma glucose, insulin, C peptide, and glycated hemoglobin (HbA1c); determining the number of β cells in the pancreatic islets; and performing the glucose tolerance test. Furthermore, the effects of the ethanolic extracts on the lipid profile and liver function were estimated. After rats were sacrificed, their pancreases were isolated and used for histopathological processing. The results indicated that the antioxidant potential and antioxidant metabolite content were significantly increased under microgravity conditions in comparison to those under normal gravity conditions. Rats treated with an extract of wheatgrass (T. aestivum) germinated over a period of 6-10 days under microgravity (WGM) showed a significant reduction in the levels of serum glucose, HbA1C, urea, creatinine, aspartate aminotransferase and alanine aminotransferase, and insulin resistance compared to rats treated with an extract of wheatgrass germinated under gravity. Additionally, the total cholesterol and low-density lipoprotein cholesterol levels were significantly decreased. In contrast, high-density lipoprotein cholesterol, C-peptide, and insulin levels rose significantly after treatment with T. aestivum germinated under microgravity. WGM is a promising potential diabetic treatment without side effects with a low manufacturing cost.

Effects of Securigera Securidaca seed extract in combination with glibenclamide on antioxidant capacity, fibroblast growth factor 21 and insulin resistance in hyperglycemic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Undesired effects of synthetic antidiabetic agents have made researchers to seek for safer and healthier resources. With this aspect, herbal materials have attracted substantial research interest and are being extensively investigated. Considering that herb-drug interactions can be a double-edged sword presenting both risks and benefits, investigation of such interactions is greatly in demand.

AIM OF THE STUDY

to investigate possible beneficial effects of hydroalcoholic extract of SecurigeraSecuridaca seed (HESS) on antioxidant capacity, fibroblast growth factor 21 (FGF21) and insulin resistance in Streptozotocin (STZ)-induced diabetic rats, alone and in combination with glibenclamide.

MATERIALS AND METHODS

Forty male Wistar rats were randomly divided in to eight equal groups including healthy and diabetic controls and six treated groups with a various doses of HESS alone and in combination with glibenclamide, for 35 consecutive days. Serum samples were taken and analyzed for biochemical profile, HOMA indexes, FGF21, oxidative/nitrosative stress and inflammatory biomarkers as compared with the controls. Moreover, total phenolic and flavonoid contents of herbal extract were assessed.

RESULTS

The herbal extract was found to be rich in flavonoid and phenolic components. Both of glibenclamide and the HESS decreased glucose and insulin resistance, as well as increased body weight and insulin sensitivity. Moreover, the extract could mitigate oxidative/nitrosative stress and inflammation dose-dependently, however, the standard drug was less effective than HESS. Induction of diabetes increased FGF21 levels and both of the treatments could reduce its contents, however, glibenclamide was more effective than HESS.

CONCLUSIONS

The results clearly show that there is no contradiction between HESS and glibenclamide. Moreover, the herbal extract could augment antioxidant and anti-inflammatory properties of the standard drug.

A dipyrrole derivative from Aloe vera inhibits an anti-diabetic drug target Dipeptidyl Peptidase (DPP)-IV in vitro

Aloe vera, a succulent herb, has a long history of use in traditional medicine, including diabetes. Earlier studies from our laboratory demonstrated that the Aloe vera extract has the ability to inhibit the diabetic drug target dipeptidyl peptidase (DPP) IV in vitro. This current study focuses on the isolation of small water soluble active molecule(s) involved in DPP-IV inhibition from Aloe vera extract, and further to characterize its structure and to elucidate the mode of inhibition of the DPP-IV enzyme. Aloe vera gel ethanolic extract was subjected to preparative reverse-phase high-pressure liquid chromatography (RP-HPLC), LH-20 Sephadex gel filtration chromatography, followed by analytical RP-HPLC, to isolate the active molecule involved in DPP-IV inhibition. Based on the spectroscopic studies, the structure of the isolated DPP-IV inhibitor was predicted to be 3, 6-dioxo-3, 3a, 6, 6 a-tetrahydropyrrolo [3, 4-c] pyrrole-1, 4-dicarboxamide with the chemical formula C8H6N4O4, having the molecular weight of 225.175 Da. This molecule inhibited the DPP-IV enzyme in a noncompetitive manner with an IC50 value of 8.59 ± 2.61 µM, with a Ki of 4.7 ± 0.038 µM. Thus, the mechanism of DPP-IV inhibition and the inhibitory constants were determined. The results of our studies suggested that the inhibition of the DPP-IV enzyme as one of the pathways by which the Aloe vera extract may restore the pancreatic islets cell mass in diabetic animal model.

The Biological Impacts of Sitagliptin on the Pancreas of a Rat Model of Type 2 Diabetes Mellitus: Drug Interactions with Metformin

Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is a beneficial class of antidiabetic drugs. However, a major debate about the risk of developing pancreatitis is still existing. The aim of the work was to study the histological and immunohistochemical effects of sitagliptin on both endocrine and exocrine pancreases in a rat model of type 2 diabetes mellitus and to correlate these effects with the biochemical findings. Moreover, a possible synergistic effect of sitagliptin, in combination with metformin, was also evaluated. Fifty adult male rats were used and assigned into five equal groups. Group 1 served as control. Group 2 comprised of untreated diabetic rats. Group 3 diabetic rats received sitagliptin. Group 4 diabetic rats received metformin. Group 5 diabetic rats received both combined. Treatments were given for 4 weeks after the induction of diabetes. Blood samples were collected for biochemical assay before the sacrification of rats. Pancreases were removed, weighed, and were processed for histological and immunohistochemical examination. In the untreated diabetic group, the islets appeared shrunken with disturbed architecture and abnormal immunohistochemical reactions for insulin, caspase-3, and inducible nitric oxide synthase (iNOS). The biochemical findings were also disturbed. Morphometrically, there was a significant decrease in the islet size and islet number. Treatment with sitagliptin, metformin, and their combination showed an improvement, with the best response in the combined approach. No evidence of pancreatic injury was identified in the sitagliptin-treated groups. In conclusion, sitagliptin had a cytoprotective effect on beta-cell damage. Furthermore, the data didn't indicate any detrimental effects of sitagliptin on the exocrine pancreas.

Anil Kumar N, Sharopov F, Ramírez-Alarcón K, Ruiz-Ortega A, Abdulmajid Ayatollahi S, Valere Tsouh Fokou P, Kobarfard F, Amiruddin Zakaria Z, Iriti M, Taheri Y, Martorell M, Sureda A, N. Setzer W, Durazzo A, Lucarini M, Santini A, Capasso R, Adrian Ostrander E, -ur-Rahman A, Iqbal Choudhary M, C. Cho W, Sharifi-Rad J. Antidiabetic Potential of Medicinal Plants and Their Active Components

Diabetes mellitus is one of the major health problems in the world, the incidence and associated mortality are increasing. Inadequate regulation of the blood sugar imposes serious consequences for health. Conventional antidiabetic drugs are effective, however, also with unavoidable side effects. On the other hand, medicinal plants may act as an alternative source of antidiabetic agents. Examples of medicinal plants with antidiabetic potential are described, with focuses on preclinical and clinical studies. The beneficial potential of each plant matrix is given by the combined and concerted action of their profile of biologically active compounds.

Protective effect of hypoxylonol C and 4,5,4',5'-tetrahydroxy-1,1'-binaphthyl isolated from Annulohypoxylon annulatum against streptozotocin-induced damage in INS-1 cells

We evaluated the protective effects of hypoxylonol C and 4,5,4',5'-tetrahydroxy-1,1'-binaphthyl (BNT) isolated from Annulohypoxylon annulatum on pancreatic β-cell apoptosis, using the β-cell toxin streptozotocin (STZ). Hypoxylonol C and BNT restored the STZ-induced decrease in INS-1 cell viability in a dose-dependent manner. In addition, treatment of INS-1 cells with 50 μM STZ resulted in an increase in apoptotic cell death, which was observed as annexin V fluorescence intensity. Apoptotic cell death was decreased by co-treatment with 100 μM hypoxylonol C and 100 μM BNT. Similarly, STZ caused a marked increase in the expression of cleaved caspase-8, caspase-3, Bax, and poly (ADP-ribose) polymerase (PARP), as well as a decrease in the expression of B-cell lymphoma 2 (Bcl-2), which was reversed by co-treatment with 100 μM hypoxylonol C and 100 μM BNT. These findings suggest that hypoxylonol C and BNT play an important role in protecting pancreatic β-cells against apoptotic damage.

Ethnomedicinal Investigation of Medicinal Plants of Chakrata Region (Uttarakhand) Used in the Traditional Medicine for Diabetes by Jaunsari Tribe

The Himalayan region is the treasure house of natural wealth, particularly of medicinal and aromatic plants. These plants are used by the Indian traditional healers for the past many centuries to treat various ailments such as skin disorders, asthma, diabetes, snake bite, fever, pain, eye diseases, diarrhoea, indigestion, jaundice, burn, wound, liver disorder, CNS disorders and urinary tract infection. The indigenous traditional knowledge of medicinal plants and therapies of various local communities has been lost due to changes in traditional culture and the introduction of modern technologies. Therefore, it is essential to explore the traditional knowledge of the indigenous medicinal plants mainly in such areas where there is a severe threat to natural vegetation owing to human inhabitation. The present study aimed to explore the medicinal plants of Chakrata region (Jaunsar-Bawar Hills), Uttarakhand, India used in the folk medicine for the management of diabetes by Jaunsari Tribe. In a comprehensive field survey, the information about the medicinal plants have been mainly collected from the traditional healers and other elderly people belong to the tribal community. All the information about the medicinal plants of the study area was documented in a field book. Various tools have been used to collect the samples for identification purpose and the authentication of the plants was done with the help of taxonomists. The literature on these plants was also searched from online (PubMed and Scopus) as well as from some textbooks and Ayurvedic classical texts. The present survey-based work described a total of 54 plants belonging to 47 genera and 30 families used in the traditional medicine for the management of diabetes in Chakrata region. The information gathered from the local community revealed that the plants are effective in diabetes and one can use most of them without consulting a practitioner or traditional healer. The literature revealed that most of the surveyed plants are already used in the preparation of various antidiabetic formulations such as Chandraprabha vati, Nishamalaki chunra, Amritamehari churna and Nisakathakadi kashayam along with various patent drugs which are frequently prescribed by the Ayurvedic practitioners in India. The present study explored the traditional as well as scientific knowledge on the antidiabetic plants used by the tribal community. The documented information on these plants can be further used by the scientific community to develop new drugs/formulations with the help of modern techniques.

α-Amylase and α-glucosidase inhibitor effects and pancreatic response to diabetes mellitus on Wistar rats of Ephedra alata areal part decoction with immunohistochemical analyses

Ephedra alata, known as a medicinal plant in China, was used in this study as aqueous extract from aerial parts, for diabetes mellitus treatment. This study was carried out on two parts, in vitro, we tested the effect of the studied extract on the inhibition of α-glucosidase and α-amylase activities, and in vivo on Wistar male rats receiving alloxan intraperitoneally at a rate of 125 mg/kg. Extract (100, 200, and 300 mg/kg of body weight) was administrated for 28 days by oral gavage. Blood glucose, amylase, lipase, and lipid profile level were determined. Oxidative stress was evaluated by enzymatic activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and by estimation of lipid peroxidation and protein carbonyl (PC) level. Histopathological changes in pancreas were investigated under photonic microscopy using immunohistochemical procedure. Our findings showed that aqueous extract inhibited in vitro both α-glucosidase and α-amylase activities and its use in vivo at 300 mg/kg of body weight restored pancreas weight and weight gain, ameliorated significantly (p ˂ 0.05) biochemical parameters; it prevented the increase in lipid and protein oxidation and the decrease in enzymatic and non-enzymatic defense system. Histological study of treated animals showed a comparable healed regeneration of beta cells.