Antidiabetic activity of extracts of Anacardium occidentale Linn. leaves on n-streptozotocin diabetic rats

Antidiabetic and hepato-renal protective effects of medicinal plants in STZ induced diabetic rats

Abstract The antidiabetic and hepato-renal protective effects of Citrullus colocynthis and Momordica charantia ethanol extracts were investigated in streptozotocin (STZ) induced diabetic male albino rats. Diabetic rats were treated with C. colocynthis, M. charantia or C. colocynthis + M. charantia mixed extract at a dose of 250 mg /kg body weight per oral per day for 21 days. The mean body weight of all the diabetic rat groups on day 1 of treatment (day 10 of diabetes) was significantly lower than the normal control rat group (P<0.05). The blood glucose level of all the diabetic rat groups on day 1 of treatment (day 10 of diabetes) was significantly (P<0.05) higher (> 200 mg/dl) than the normal control rat group (95.5 ± 2.7). At the end of treatment (day 21), the diabetic rats treated with plant extracts showed significant increase (P<0.05) in body weight and significant (P<0.05) reduction in blood glucose level when compared to diabetic control animals. Significant increase (< 0.05) was observed in the serum bilirubin, alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), urea and creatinine levels of diabetic control rat group. The serum levels of these liver and kidney-related parameters of diabetic rats treated with plant extract were significantly lower when compared to diabetic control rat group (p < 0.05). Photomicrographs of liver and kidney microsections from diabetic rats treated with these plant extracts showed amelioration in the hepato-renal histoarchitectures. It was concluded that the C. colocynthis and M. charantia methanol extracts are antidiabetic and hepato-renal protective in STZ induced diabetic male rats. Treatment of the diabetic rats with C. colocynthis + M. charantia mixed extract is more effective in the amelioration of diabetes and hepato-renal injuries in STZ induced diabetic male rats.

Controlling diabetes with the aid of medicinal herbs: a critical compilation of a decade of research

Diabetes is a metabolic disorder owing to the insulin faulty production or the resistance to the action mechanism where the accumulation of glucose is the major side effect in the body in the case of diabetes. Numerous herbs with the potential of reducing glucose production along with combating the secondary ailments associated with it but >1% out of 250,000 have been pharmacologically validated. Affordability and historical usage of these herbal remedies often result in patients' preference as primary or as adjunctive to conventional therapies. Clinical trials conducted with herbs are necessary for determining the efficacy of the herbs against diabetes. Additional benefits of herbal employment include the treatment of secondary ailments in patients along with diabetes including triglyceride reduction, cholesterol level management, body mass index, and cardiovascular disease control. Any individual extract marketed as antidiabetic formulations requires clinical validation before adoption but with ongoing disease status, quick validation in protocols and testing is needed to understand, isolate and cross-verify the status of the bioactive ingredient in individual herb and the polyherb extract formulations. Standardization, characterization, long-term role and impact on the human body, efficacy status, and toxicity profile need to be addressed fully for each active ingredient before it is advanced for production. Therefore, after trials, the related regulatory bodies will be approached to confirm the safety status and efficacy of the prepared concoction.

Ethnomedicinal Knowledge of Plants Used in Nonconventional Medicine in the Management of Diabetes Mellitus in Kinshasa (Democratic Republic of the Congo)

Background

People with diabetes, herbalists, and traditional medicine practitioners (TMPs) from Kinshasa use plants to treat diabetes, but no study has inventoried the plants used by these populations. The present study was conducted to identify the plants used in Kinshasa to treat diabetes mellitus.

Methods

The survey conducted in the form of a semistructured interview between March 2005 and August 2006 made it possible to collect ethnobotanical information from people with diabetes (n = 126), herbalists (n = 80), and TMPs (n = 120).

Results

The 326 subjects consulted (sex ratio M/F = 0.6, age 51 ± 7 years, and experience: 17 ± 5 years) provided information on 71 plants, most of which are trees (35%), belonging to 38 families dominated by Fabaceae (19.7%) and indicated in 51 other cases of consultation dominated by malaria (12%). From these 71 plants derived, 86 antidiabetic recipes were administered orally, where the leaf is the most used part (>50%) and the decoction (>46%) is the most common mode of preparation. This study reports for the first time the antidiabetic use of 11 species, among which Tephrosia vogeliiX (0.08), Chromolaena corymbosaX (0.06), and Baphia capparidifoliaX (0.06) present the highest consensus indexes (CI) and Marsdenia latifoliaW (UVp = 0.08) and Rauvolfia manniiX (UVp = 0.06) present the highest UVs.

Conclusion

The results show that Kinshasa people treat diabetes using several plants. Some are specific to the ecological environment; others are used in other regions. Pharmacological studies are underway to assess the therapeutic efficacy of these plants.

Crude extract from Euphorbia prostrata extended curative period of glibenclemide in alloxan-induced diabetic rats

OBJECTIVES

Euphorbia prostrata is traditionally used alongside antidiabetic agents to manage diabetes. Bioactive ingredients of medicinal herbs may alter the overall pharmacokinetics of antidiabetic agents.

METHODS

We assessed hypoglycemic activities of ethanolic plant extract (EPE) singly and its effects on antidiabetic properties of gliclazide, glibenclemide and metformin in allaxonized rats. Varying concentrations of EPE (250 and 500 mg/kg) with or without metformin (10 mg/kg), glibenclemide (2 mg/kg) and gliclazide (5 mg/kg) were orally administered to evaluate herb-drug interaction.

RESULTS

The levels of blood glucose declined significantly after treatment with metformin, glibenclemide and gliclazide singly (p<0.01) or concomitantly with EPE (p<0.001). Concentration dependent mild to moderate reduction (5.2 and 10.0%) was registered in blood glucose for 250 and 500 mg/kg of EPE respectively. The overall reduction in blood glucose due to combined treatment with EPE and standard agents was additive. On the other hand, synergistic herb-drug interaction was registered for insulin levels in rats that received glibenclamide and gliclazide alongside EPE. Extract with metformin had antagonistic insulin outcome. Regarding the duration of hypoglycemic activities, periodical changes were similar in case of glibenclamide and gliclazide separately or in combination with EPE. However, in case of metformin with extract, the blood glucose continued to decline for 14 h and retained at 15.0% below the baseline values even after 24 h of treatment.

CONCLUSIONS

In conclusion, the extract itself had weak hypoglycemic effects but prolonged the therapeutic duration of metformin to more than 24 h when administered combinedly.

Anacardium occidentale leaves extract and riboceine mitigate hyperglycemia through anti-oxidative effects and modulation of some selected genes associated with diabetes

Background

Diabetes mellitus (DM) is one of the leading causes of death globally and complications of DM have become a major health concern. Anacardium occidentale is a plant widely recognized for its hypoglycemic properties and traditionally used in developing nations as remedy for DM treatment. Riboceine is a supplement that enhances production of glutathione and known for its vital role in supporting cellular function. This study was designed to evaluate the antidiabetic and antioxidant potential of riboceine and ethanolic extract of A. occidentale leaves in streptozotocin (STZ)-induced diabetic rats.

Method

Twenty-nine adult male Wistar rats were induced with DM intraperitoneally using a single dose of STZ (70 mg/kg). The STZ-induced rats were divided into groups and administered the same dose (100 mg/kg) of A. occidentale leaves extract and riboceine via gastric gavage at the dose (100 mg/kg) for seventeen days while metformin (40 mg/kg) was used as positive control. Fasting blood glucose and weight of the model rats were examined periodically. Activities of total protein, creatinine, urea, antioxidants (SOD, GSH and GPX), and level of serum insulin were determined. Expression of diabetes related genes including pancreas (Insulin, pdx-1, P16NK4A, and Mki-67), Liver (FAS, ACC, and GFAT) and KIM-1 genes were also determined.

Results

Data showed that treatment of STZ-induced diabetic rats with A. occidentale and riboceine at the same dose significantly (p < 0.05) ameliorated hyperglycemic effects by improving hepatic and renal functions and antioxidants, preventing hepatic fat accumulation by downregulation of ACC, FAS and GFAT expression, improving β-cell functions through up-regulation of pancreatic insulin, P16NK4A, Mki-67 and pdx-1 expression. Induction of diabetes upregulated mRNA expression of KIM-1, which was ameliorated after treatment of the rats with A. occidentale and riboceine.

Conclusion

The results obtained in this study demonstrate significant antidiabetic properties of ethanolic extract of A. occidentale and riboceine.

In vitro and in vivo antidiabetic activity of bitter honey in streptozotocin-nicotinamide-induced diabetic Wistar rats

Diabetes mellitus is a metabolic syndrome considered one of the life-threatening diseases in the last two decades. This research aimed to investigate the anti-diabetic potential of bitter honey collected from Nilgiris using both in vitro and in vivo methods. The mineral content of bitter honey was also estimated using atomic absorption spectrophotometer. Bitter honey had a higher amount of zinc and copper, while heavy metals like lead, nickel, and cadmium were below the detection limit. The in vitro antidiabetic study was performed using alpha-amylase and alpha-glucosidase inhibition methods. Acute toxicity (OECD 423) was conducted in female Wistar rats to determine the lethal dose of bitter honey. The antidiabetic activity was carried out in type-2 diabetic Wistar Albino rats induced with streptozotocin and nicotinamide. The experimental rats were categorized into five groups (n=8): the normal group, the diabetic control group, standard glibenclamide-treated diabetic group, bitter honey 200 mg/kg, and 400 mg/kg b.w. treated diabetic group. After the treatment period (28 days), blood samples were collected for biochemical studies, and the pancreas was dissected for histopathological studies. The in vitro antidiabetic studies revealed the antidiabetic potential of bitter honey compared to standard acarbose. Treatment of diabetic rats with bitter honey revealed a statistically significant reduction (P<0.05) in the levels of fasting blood glucose (FBG) compared to untreated diabetic rats. This was accompanied by an elevated HDL and a decrease in LDL, VLDL, triglycerides, total cholesterol, SGOT, SGPT, urea, and creatinine. Histopathological changes in the pancreas indicated a marked improvement in a dose-dependent manner. The study concluded that bitter honey could potentially decrease the levels of FBG in diabetic rats and the various biochemical and histopathological abnormalities associated with diabetes mellitus.

Plant bioactive compounds and their mechanistic approaches in the treatment of diabetes: a review

Background

Diabetes mellitus (DM) is a growing disease across the world; diabetes is a complex metabolic disorder in which blood glucose concentration level increases and continue for a prolonged period due to a decrease secretion of insulin or action, resulting in the disorder of carbohydrate, lipid, and protein metabolism. The plant-related bioactive compounds have proven their efficacy with least toxicities and can be utilized for the disease treatment. Our objective is to elucidate the mechanism of action of plant bioactive compounds which can give future direction in diabetes treatment.

Main body

In this review paper, we briefly study more than 200 research papers related to disease and bioactive compounds that have therapeutic applicability in treatment. The plant contains many bio-active compounds which possess in vitro and in vivo anti-diabetic effect which may be responsible for the hypoglycaemic property by inhibiting the digestive enzyme i.e. alpha-amylase and alpha-glucosidase, by producing mimetic action of insulin, by reducing the oxidative stress, by showing antihyperglycemic activity and hypolipidemic activity, by inhibition of aldose reductase, and by increasing or enhancing glucose uptake and insulin secretion.

Conclusion

Our study revealed that terpenes, tannin, flavonoids, saponin, and alkaloids are important bioactive constituents for anti-diabetic activity. The mechanistic approach on alpha-glucosidase and alpha-amylase, hypolipidemic activity, and AR inhibitory action clear-cut explain the therapeutic applicability of these bioactive compounds in disease. Plants that contain these bioactive compounds can be good drug candidates for future research on diabetes treatment.

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.

Antidiabetic Potential of Plants from the Caribbean Basin

Diabetes mellitus (DM) is a group of metabolic disorders characterized by hyperglycemia, insulin insufficiency or insulin resistance, and many issues, including vascular complications, glycative stress and lipid metabolism dysregulation. Natural products from plants with antihyperglycemic, hypolipidemic, pancreatic protective, antioxidative, and insulin-like properties complement conventional treatments. Throughout this review, we summarize the current status of knowledge of plants from the Caribbean basin traditionally used to manage DM and treat its sequelae. Seven plants were chosen due to their use in Caribbean folk medicine. We summarize the antidiabetic properties of each species, exploring the pharmacological mechanisms related to their antidiabetic effect reported in vitro and in vivo. We propose the Caribbean flora as a source of innovative bioactive phytocompounds to treat and prevent DM and DM-associated complications.

Monoclonal Antibody Functionalized, and L-lysine α-Oxidase Loaded PEGylated-Chitosan Nanoparticle for HER2/Neu Targeted Breast Cancer Therapy

Simple Summary

Breast cancer is one of the dominant cancers that threaten human beings worldwide. Moreover, the treatment of HER2+ breast cancer is challenging due to heterogeneity. The L-lysine α-oxidase (LO) enzyme is a well-known antitumor enzyme, but its clinical utility has been limited due to side effects, decreased stability, and inability to target tumor cells. To overcome the clinical challenges in delivery of LO enzymes and improve HER2+ breast cancer therapeutics, the present study developed the dual stimuli responsive nanocarrier system (CS-LO-PEG-HER NPs) for pH sensitive and HER2/neu targeted breast cancer therapy.

Abstract

Herein, we designed a nanocarrier to deliver the LO specifically to HER2+ breast cancer (BC) cells, where functionalization of mAb (anti-HER2+) with PEGylated chitosan enabled it to target the HER2+ BC cells. Taking advantage of overexpression of HER2+ in cancer cells, our nanocarrier (CS-LO-PEG-HER NPs) exhibited promising potency and selectivity against HER2+ BC cells (BT474). The CS-LO-PEG-HER NPs demonstrated the cytotoxicity in BT474 cells by promoting reactive oxygen species, mitochondrial membrane potential loss, and nucleus damage. The biocompatibility of CS-LO-PEG-HER NPs was evidenced by the hemolysis assay and H & E staining of major organs. The CS-LO-PEG-HER NPs showed anticancer potency against the BT474-xenograft tumor-bearing mice, as evident by the reduction of tumor size and cell density. These results indicate that CS-LO-PEG-HER NPs are biocompatible with mice while inhibiting tumor growth through alter the oxidative stress. Overall, this work provides a promising approach for the delivery of LO for good therapeutic effect in combination with mAb.

Fucoidan ameliorates glucose metabolism by the improvement of intestinal barrier and inflammatory damage in type 2 diabetic rats

It has been reported that fucoidan possesses anti-diabetic activities by inhibiting α-glucosidase activity, improving β-cell dysfunction, and enhancing insulin sensitivity. However, as a macromolecular carbohydrate, fucoidan is rarely absorbed and indigestible in gastrointestinal tract. The study aimed to explore whether the fucoidan can regulate glucose metabolism by improving intestinal barrier and inflammation in type 2 diabetes mellitus (T2DM) rats. A high-fat diet combined with streptozotocin was used to induce T2DM rats. Different doses of fucoidan (50, 100 and 200 mg/kg) were administered respectively by lavage to T2DM rats for 8 weeks and saline was given to controls. The results showed that in addition to hyperglycemia and hyperlipidemia, T2DM rats were also characterized by increased intestinal permeability and proinflammatory cytokines. Notably, fucoidan reduced fasting blood glucose and insulin resistance index along with alleviated the accumulation of proinflammatory cytokines in T2DM rats. Furthermore, fucoidan repaired the intestinal barrier function, which was accompanied by the up-regulation of tight junction proteins and the improvement of intestinal inflammation via inhibiting TLR4/NF-κB signaling. Meanwhile, fucoidan also mitigated the liver damage, and alleviated insulin resistance by activating PI3K/AKT signaling. Collectively, these findings supported the potential of fucoidan to be used as a functional ingredient to prevent T2DM.

The Effect of Strobilanthes crispus on Blood Glucose Levels and Lipid Profile of Streptozotocin-induced Diabetic Rats

BACKGROUND: Diabetes mellitus is a metabolic disease associated with unhealthy eating patterns, a lack of physical activity, obesity, smoking habits, and family history. Strobilanthes crispus (SC) contains antioxidant compounds known to exert a hypoglycemic effect during long-term interventions in non-diabetic samples. AIM: This study sought to determine the effect of administering the extract of SC leaves on the blood glucose levels and blood serum lipid profiles of streptozotocin (STZ)-induced diabetic rats. METHODS: A total of 30 male Rattus norvegicus rats were divided into control and treatment groups. The control groups consisted of negative (normal rats) and positive controls (diabetic rats), whereas the treatment groups consisted of diabetic rats administered with 3.2% and 16.8% SC leaf extract, and glibenclamide as the drug comparison groups. Blood samples were collected from the rats’ retro-orbital vein for the purposes of glucose level and lipid profile measurement before and after the induction of diabetes with STZ as well as 14 days after the intervention. The collected data were analyzed statistically by means of a one-way analysis of variance continued with Duncan’s multiple range test. RESULTS: The results showed the rats to be hyperglycemic experienced changes in their lipid profiles following the induction of diabetes. The administration of 3.2% SC leaf extract for 14 days reduced the rats’ blood glucose levels, while the effect of the 16.8% SC leaf extract was more pronounced in terms of reducing the rats’ blood glucose levels and improving their lipid profiles (reducing the triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels, while increasing the high-density lipoprotein cholesterol levels). CONCLUSIONS: This study found 16.8% SC leaf extract to exert a good hypoglycemic effect and leads to an improvement in the lipid profiles in diabetic rats.

Metabolome-based profiling of African baobab fruit (Adansonia digitata L.) using a multiplex approach of MS and NMR techniques in relation to its biological activity

Adansonia digitata L. also known as African baobab is one of the most important fruit-producing trees, widely distributed in the African continent. Baobab fruits are known to possess potential health benefits and nutritional value. This study aimed to holistically dissect the metabolome of A. digitata fruits using a novel comparative protocol using three different analytical platforms. Ultra high performance liquid chromatography coupled to high-resolution tandem mass spectrometry (UHPLC-HRMS/MS), and headspace solid-phase microextraction/gas chromatography coupled to mass spectrometry (HS-SPME/GC-MS) were respectively employed for phytonutrients and aroma profiling, whereas GC-MS post silylation provided an overview of nutrients i.e., sugars. UHPLC-HRMS/MS analysis allowed for the assignment of 77 metabolites, among which 50% are reported for the first time in the fruit. While GC-MS of silylated and aroma compounds led to the identification of 74 and 16 compounds, respectively. Finally, NMR-based metabolite fingerprinting permitted the quantification of the major metabolites for future standardization. In parallel, in vivo antidiabetic potential of the baobab fruit using a streptozotocin (STZ) induced diabetic rat model was assessed. Histopathological and immune-histochemical investigations revealed hepatoprotective and renoprotective effects of A. digitata fruit along with mitigation against diabetes complications. Moreover, the administration of A. digitata fruits (150 mg kg-1) twice a week lowered fasting blood glucose levels.

An Overview on the Therapeutic Function of Foods Enriched with Plant Sterols in Diabetes Management

Diabetes is one of the most significant health issues across the world. People identified with diabetes are more vulnerable to various infections and are at a greater risk of developing cardiovascular diseases. The plant-based food we consume often contains many sterol-based bioactive compounds. It is well documented that these compounds could effectively manage the processes of insulin metabolism and cholesterol regulation. Insulin resistance followed by hyperglycemia often results in oxidative stress level enhancement and increased reactive oxygen species production. At the molecular level, these changes induce apoptosis in pancreatic cells and hence lead to insulin insufficiency. Studies have proved that plant sterols can lower inflammatory and oxidative stress damage connected with DNA repair mechanisms. The effective forms of phyto compounds are polyphenols, terpenoids, and thiols abundant in vegetables, fruits, nuts, and seeds. The available conventional drug-based therapies for the prevention and management of diabetes are time-consuming, costly, and with life-threatening side effects. Thereby, the therapeutic management of diabetes with plant sterols available in our daily diet is highly welcome as there are no side effects. This review intends to offer an overview of the present scenario of the anti-diabetic compounds from food ingredients towards the therapeutic beneficial against diabetes.

An evaluation of pharmacological healing potentialities of Terminalia Arjuna against several ailments on experimental rat models with an in-silico approach

Herbal remedies have been used in many cultures for decades to treat illnesses. These medicinal plants have been found to contain various phytochemical compounds that can help to cure mild to severe illnesses. The inadequacies of conventional medicines and their unusual side effects sparked a determined search for alternative natural therapeutic agents. Another reason for this hunt could be the availability and fewer side effects of natural products. T. arjuna is widely used in traditional medicine to alleviate various diseases like relieving pain, ameliorating diabetes, mitigating inflammation, and back-pedaling of depression. In this study, the ethanolic extract of T. arjuna possesses a promising effect on the animal model (p < 0.05/p < 0.01) as an antihyperglycemic, analgesic, anti-inflammatory, and antidepressant agent, but in a dose-dependent manner. The lower dose of T. arjuna was found to be capable of reversing the disturbed physiological state at a significant level (p < 0.05). However, a higher dose of T. arjuna exerts better therapeutic effects for those diseases. This animal study aims to evaluate the anti-diabetic, anti-depressant, and anti-inflammatory properties of T. arjuna compared to conventional marketed drugs. We will perform an in-silico study for active constituents of T. arjuna against their proposed targets and look for the molecular cascade on their claimed pharmacological properties. This study shows that different doses of T. arjuna bark extracts give similar therapeutic responses compared with established marketed drugs in managing hyperglycemia, stress-induced depression, and inflammation. Besides, our docking study reveals that flavonoids and triterpenoid active constituents of T. arjuna play an important role in its usefulness. This study, therefore, scientifically confirmed the traditional use of this medicinal plant in the management of several diseased conditions.

Chemical composition, antioxidant, and anti-diabetic activities of ethyl acetate fraction of Stachys riederi var. japonica (Miq.) in streptozotocin-induced type 2 diabetic mice

This work analysed the chemical composition, antioxidant, and enzyme inhibitory activities of solvent extract (SJ-ME) and fractions (SJ-HF, SJ-EAF, and SJ-MF) of the Stachys riederi var. japonica (Miq.) (SJ). Furthermore, the effect of SJ-EAF in STZ induced type 2 diabetic mice was examined. Among the samples, SJ-EAF exhibited a lower IC50 concentration of 64.2 ± 0.48 μg/mL for DPPH and 82.6 ± 0.09 μg/mL for ABTS+. The SJ-EAF concentration of 2.89 ± 0.03 μg and 2.27 ± 0.98 μg was equivalent to 1 μg of acarbose mediated enzyme inhibitory effect against α-amylase and α -glucosidase, respectively. The SJ-EAF did not show cytotoxicity (<80%) to NIH3T3 nor HepG2 cells but enhanced the glucose uptake in the IR-HepG2. LC-MS/MS of SJ-EAF showed the presence of a total of 16 compounds. Among the identified compounds, rosmarinic acid, caffeic acid, oleanolic acid, and ursolic acid showed high catalytic activity of α-amylase and α-glucosidase. The treatments of SJ-EAF restored the level of blood glucose, body weight, insulin, HDL and mRNA level of IRS1, GLUT2, GLUT4 and Akt whereas it reduced the excess elevation of total cholesterol, total triglycerides, LDL, AST, ALT, ALP, BUN, and creatinine in STZ induced diabetic mice. Overall, the present study concluded that the SJ-EAF exhibited promising antidiabetic activity.

Gallic acid anti-myotoxic activity and mechanism of action, a snake venom phospholipase A2 toxin inhibitor, isolated from the medicinal plant Anacardium humile

Snakebite envenoming is the cause of an ongoing health crisis in several regions of the world, particularly in tropical and neotropical countries. This scenario creates an urgent necessity for new practical solutions to address the limitations of current therapies. The current study investigated the isolation, phytochemical characterization, and myotoxicity inhibition mechanism of gallic acid (GA), a myotoxin inhibitor obtained from Anacardium humile. The identification and isolation of GA was achieved by employing analytical chromatographic separation, which exhibited a compound with retention time and nuclear magnetic resonance spectra compatible with GA's commercial standard and data from the literature. GA alone was able to inhibit the myotoxic activity induced by the crude venom of Bothrops jararacussu and its two main myotoxins, BthTX-I and BthTX-II. Circular dichroism (CD), fluorescence spectroscopy (FS), dynamic light scattering (DLS), and interaction studies by molecular docking suggested that GA forms a complex with BthTX-I and II. Surface plasmon resonance (SPR) kinetics assays showed that GA has a high affinity for BthTX-I with a K_D of 9.146 × 10^-7 M. Taken together, the two-state reaction mode of GA binding to BthTX-I, and CD, FS and DLS assays, suggest that GA is able to induce oligomerization and secondary structure changes for BthTX-I and -II. GA and other tannins have been shown to be effective inhibitors of snake venoms' toxic effects, and herein we demonstrated GA's ability to bind to and inhibit a snake venom PLA₂, thus proposing a new mechanism of PLA₂ inhibition, and presenting more evidence of GA's potential as an antivenom compound.

Root extracts of Anacardium occidentale reduce hyperglycemia and oxidative stress in vitro

Background

Hyperglycemia is the hallmark of diabetes, and the associated oxidative stress is a major concern that invites an array of diabetic complications. The traditional practices of medicare are of great, current interest due to the high cost and side effects of conventional diabetic medications. The present in vitro study focuses on evaluating the potential of various A. occidentale root extracts for their antihyperglycemic and antioxidant potentials.

Materials and methods

The four different solvent extracts petroleum ether (PEAO), chloroform (CHAO), ethyl acetate (EAAO), and 80 % methanol (80 % MAO) of A. occidentale roots were evaluated for their total phenolic, flavonoid, and antioxidant capacity. Using MIN6 pancreatic β-cells, the cytotoxicity of the extracts was evaluated by MTT assay and the antidiabetic potential by quantifying the insulin levels by ELISA at a higher concentration of glucose. The effect of 80 % MAO on INS gene expression was determined by qRT PCR analysis.

Results

Among the four different solvent extracts of A. occidentale roots, 80 % MAO showed the highest concentration of phenolics (437.33 ± 0.03 µg GAE/mg), CHAO to be a rich source of flavonoids (46.04 ± 0.1 µg QE/mg) and with the highest total antioxidant capacity (1865.33 ± 0.09 µg AAE/ mg). Evaluation of the free radical scavenging and reducing properties of the extracts indicated 80 % MAO to exhibit the highest activity. The MTT assay revealed the least cytotoxicity of all four extracts. 80 % MAO enhanced INS up-regulation as well as insulin secretion even under high glucose concentration (27mM).

Conclusions

The present study demonstrated that the A. occidentale root extracts have effective antihyperglycemic and antioxidative properties, together with the potential of normalizing the insulin secretory system of β-cells. Above mentioned properties have to be studied further by identifying the active principles of A. occidentale root extracts and in vivo effects. The prospect of the present study is identifying drug leads for better management of diabetes from the A. occidentale root extracts.

Graphical abstract

Effect of Adhatoda zeylanica Ethanolic Extract on Attenuated Kidney in Streptozotocin-Induced Diabetic Rats

Objective The present study was aimed to evaluate the effect of ethanolic extract of Adhatoda zeylanica (EAZ) leaves on streptozotocin (STZ)-induced diabetes mellitus (DM) and its renal complications in male Wistar albino rats.

Materials and Methods Adult male Wistar albino rats were randomly selected from a colony, divided into four groups, namely, A, B, C, and D, with each having six rats (n = 6) and each weighing between 200 and 250 g. Group A served as control and received only water per oral (p.o.). Group B, C, and D animals received a single dose of STZ at 45 mg/kg body weight (kbw) intraperitoneal administration (i.p.) on day 1 and observed for fasting blood glucose (FBG) to induce DM for next 72 hours. After the DM was induced, group B served as DM control, group C received the standard drug glibenclamide (GL) at 5 mg/kbw p.o. once daily, and group D received EAZ of 500 mg/kbw p.o. once daily for 35 days. After the observation period, the animals were euthanized, serum creatinine and blood urea, antioxidants in the kidney tissue homogenate, and histopathological studies were assessed to know the ameliorative effect of the test drugs.

Results Renal parameters, such as serum creatinine, blood urea, antioxidants activities, in group D were nearer to the control when compared with groups B and C. Histopathological studies revealed that there was minimal renal damage in group D when compared with groups B and C.

Conclusion Administration of ethanolic EAZ showed significant ameliorative effects on the FBG, biochemical, oxidative, and histopathological parameters on kidney tissues treated with STZ to induce DM.

Trends in diabetes care with special emphasis to medicinal plants: Advancement and treatment

Diabetic mellitus (DM) is a common metabolic disorder prevailing throughout the world. It may affect a child to an older person depending upon the physiology and the factors influencing the internal metabolic system of the body. Several treatments are available in the market ranges from synthetic drugs, insulin therapy, herbal drugs, and transdermal patches. Interestingly, the development of technologies and digital health have proving very helpful in improving the lifestyle of diabetic patients. All treatment approaches have their own advantages and disadvantages in the form of effectiveness and side effects. Medicinal plants have a long history of traditional application in the treatment of diabetes and even the use of plants are growing day-by-day due to the significant results against diseases and fewer side effects as compared to other treatment therapies. The intention behind writing this review is to gather all information and discussed them exhaustively in an article. The novel Coronavirus 2019 (COVID-19) pandemic has affected my lives including diabetic patients. The antidiabetic treatment strategies during this period has also discussed. In this article, we highlighted the molecular mechanism and herbal phytoconstituents that are responsible for lowering blood glucose level. The factors responsible for the progression of metabolic disorders can be controlled with the use of phytoconstituents present in herbal plants to maintain β-cells performance and restore blood glucose level. It can be concluded that medicinal plants are effective and affordable with lesser side effects for treating DM.

Bilobalide Enhances AMPK Activity to Improve Liver Injury and Metabolic Disorders in STZ-Induced Diabetes in Immature Rats via Regulating HMGB1/TLR4/NF-κB Signaling Pathway

This study was aimed at examining the effect and underlying mechanisms of bilobalide (BB) on hepatic injury in streptozotocin- (STZ-) induced diabetes mellitus (DM) in immature rats. Immature rats (one day old) were randomly divided into five groups: group I, control nondiabetic rats; group II, STZ-induced, untreated diabetic rats; groups III/IV/V, STZ-induced and BB-treated diabetic rats, which were intraperitoneally injected with BB (2.5 mg/kg, 5 mg/kg, or 10 mg/kg) after 3 days followed by STZ treatment. We observed that BB improved the histopathological changes and maintained normal glucose metabolism, blood lipid, and liver function indicators, such as fasting blood glucose, obesity index, HbA1c, HOMA-IR, fast serum insulin, adiponectin, total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), aspartate transaminase (AST), and alanine transaminase (ALT) in STZ-induced DM in immature rats by a biochemical analyzer or ELISA. Meanwhile, Western blot analysis showed that in STZ-induced DM immature rats, BB decreased the expression of apoptosis-related proteins Bax, cleaved caspase-3, and cleaved caspase-9 while enhancing the Bcl-2 expression; BB downregulated the expression of ACC related to fat anabolism, while upregulating the expression of CPT-1 related to fat catabolism. Strikingly, treatment with BB significantly increased the expression of AMPKα1 as well as inhibited HMGB1, TLR4, and p-P65 expression in hepatic tissues of immature DM rats. AMPK inhibitor (compound C, CC) cotreated with BB undermined the protective effect of BB on the liver injury. The results of the present study suggested BB may have a significant role in alleviating liver damage in the STZ-induced immature DM rats.

Exploring the antidiabetic potential of compounds isolated from Anacardium occidentale using computational aproach: ligand-based virtual screening

Diabetes mellitus is becoming an important public health challenge worldwide and especially in developing nations. About 8.8 percent of the world adult population has been reported to have diabetes. Glutamine-fructose-6-phosphate amidotransferase 1 (GFAT1) catalyses the first committed step in the pathway for biosynthesis of hexosamines in mammals, and its inhibition has been thought to prevent hyperglycaemia. Dipeptidyl peptidase-4 (DPP-4), on the other hand, degrades hormone glucagon-like peptide-1 (GLP-1), an enzyme that plays a major role in the enhancement of glucose-dependent insulin secretion, making these two proteins candidate targets for diabetes. To find potential inhibitors of DPP-4 and GFAT1 from Anacardium occidentale using a computational approach, glide XP (extra precision) docking, Induced Fit Docking (IFD), Binding free energy of the compounds were determined against prepared crystal structure of DPP-4 and GFAT1 using the Maestro molecular interface of Schrödinger suites. The Lipinski's rule of five (RO5) and ADME properties of the compounds were assessed. Predictive models for both protein targets were built using AutoQSAR. This study identified 8 hit compounds. Most of these compounds passed the RO5 and were within the recommended range for defined ADME parameters. In addition, the predicted pIC50 for the hit compounds were promising. The results obtained from the present study can be used to design an antidiabetic drug.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-021-00084-z.

Dual mechanisms of a Sri Lankan traditional polyherbal mixture in the improvement of pancreatic beta cell functions and restoration of lipoprotein alterations in streptozotocin induced diabetic rats

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional polyherbal preparations have been utilized in Sri Lanka since ancient times and have gained a wide acceptance throughout the country. Although an extensive body of evidence supports the use of traditional herbal mixtures in the treatment of diabetes mellitus, only a few polyherbal mixtures have been subjected to systematic scientific investigations and their mechanisms for long-term glucose control remain unclear. In general, scientific evaluations of the effectiveness of antidiabetic formulations which are prescribed by traditional practitioners have received great attention, and therefore uncovering their mechanism of action would be beneficial.

AIM

The aim of the present study was to investigate the therapeutic efficacy, in terms of antidiabetic and antihyperlipidaemic activities, of a well-known traditional polyherbal mixture composed of leaves of Murraya koenigii L., -cloves of Allium sativum L., - fruits of Garcinia quaesita Pierre and seeds of Piper nigrum L. in streptozotocin induced diabetic rats.

MATERIALS AND METHODS

Equal amounts from each of the above plant parts (100 g) were mixed together and extracted into cold water, hot water (3 h, refluxed) and water-acetone (1:1) separately. Dose response study of cold water, hot water, and water-acetone extracts of the polyherbal mixture at three selected doses of 0.5 g/kg, 1.0 g/kg and 1.5 g/kg was conducted in streptozotocin (STZ) induced diabetic rats. Based on the dose response data, hot water and water-acetone extracts at the therapeutic dose of 1.0 g/kg were administered to STZ induced diabetic rats (n = 6/group) daily for 30 days in the long-term study. Glibenclamide (0.5 mg/kg) was used as the positive control. Glycaemic parameters, pancreatic β cell restoration, and lipid profile were evaluated in diabetic rats treated with the plant extract mixture. HPLC fingerprints of hot water and water-acetone extracts of the polyherbal mixture were compared with those of extracts of individual plants with the respective solvents, in the standardisation protocol.

RESULTS

The hot water and water-acetone extracts were shown to be active in the dose response study and 1.0 g/kg was selected for the long term study. Treatment with the hot water and water-acetone extracts of the polyherbal mixture and glibenclamide significantly lowered the glycated haemoglobin by 19%, 26%, and 43%, respectively, at the end of the intervention (p < 0.05). The serum insulin concentration was significantly increased (p < 0.05) upon the plant treatment, corroborating the evidence of β-cell restoration in the pancreas of H and E stained sections. Moreover, the above extracts reported an impressive restoration of lipoproteins in diabetic rats compared to the diabetic control rats. The homeostatic assessment of β-cell functions (HOMA-β) was also improved in rats treated with the hot water and water-acetone extracts of the polyherbal mixture. The HPLC fingerprints of the polyherbal mixture and the individual plants showed shifts in some peaks and formation of new peaks.

CONCLUSION

The results revealed that the aforementioned polyherbal mixture possesses potent antihyperglycaemic and antihyperlipidaemic effects with considerable restoration of pancreatic β-cells, justifying the traditional use of the mixture in diabetes associated dyslipidaemia.

Self-nanoemulsifying Delivery of Andrographolide: Ameliorating Islet Beta Cells and Inhibiting Adipocyte Differentiation

Purpose: Insulin resistance is a characteristic of non-insulin-dependent diabetes mellitus associated with obesity and caused by the failure of pancreatic beta cells to secrete sufficient amount of insulin. Andrographolide (AND) improves beta-cell reconstruction and inhibits fat-cell formation. This research aimed to improve the delivery of water-insoluble AND in self-nanoemulsifying (ASNE) formulation, tested in streptozotocin (STZ)-induced diabetic rats and 3T3-L1 preadipocyte cells.

Methods: A conventional formulation of AND in suspension was used as a control. The experimental rats were orally administered with self-nanoemulsifying (SNE) and suspension of AND for 8 days. Measurements were performed to evaluate blood glucose levels in preprandial and postprandial conditions. Immunohistochemistry was used to assess the process of islet beta cell reconstruction. In vitro study was performed using cell viability and adipocyte differentiation assay to determine the delivery of AND in the formulation.

Results: ASNE lowered blood glucose levels (day 4) faster than AND suspension (day 6). The histological testing showed that ASNE could regenerate pancreatic beta cells. Therefore, ASNE ameliorated pancreatic beta cells. The in vitro evaluation indicated the inhibition of adipocyte differentiation by both AND and ASNE, which occurred in a time-dependent manner. ASNE formulation had better delivery than AND.

Conclusion: ASNE could improve the antidiabetic activity by lowering blood glucose levels, enhancing pancreatic beta cells, and inhibiting lipid formation in adipocyte cells.

Anti-Inflammatory, Antinociceptive, and Antioxidant Properties of Anacardic Acid in Experimental Models

Anacardic acid (AA), a compound extracted from cashew nut liquid, exhibits numerous pharmacological activities. The aim of the current investigation was to assess the anti-inflammatory, antinociceptive, and antioxidant activities of AA in mouse models. For this, Swiss albino mice were pretreated with AA (10, 25, 50 mg/kg, intraperitoneally, ip) 30 min prior to the administration of carrageenan, as well as 25 mg/kg of prostaglandin E2, dextran, histamine, and compound 48/80. The antinociceptive activity was evaluated by formalin, abdominal, and hot plate tests, using antagonist of opioid receptors (naloxene, 3 mg/kg, ip) to identify antinociceptive mechanisms. Results from this study revealed that AA at 25 mg/kg inhibits carrageenan-induced edema. In addition, AA at 25 mg/kg reduced edema and leukocyte and neutrophilic migration to the intraperitoneal cavity, diminished myeloperoxidase activity and malondialdehyde concentration, and increased the levels of reduced glutathione. In nociceptive tests, it also decreased licking, abdominal writhing, and latency to thermal stimulation, possibly via interaction with opioid receptors. Taken together, these results indicate that AA exhibits anti-inflammatory and antinociceptive actions and also reduces oxidative stress in acute experimental models, suggesting AA as a promising compound in the pharmaceutical arena.

Antidiabetic effect of Drymaria cordata leaf against streptozotocin-nicotinamide-induced diabetic albino rats

Drymaria cordata (Caryophyllaceae), commonly known as Abhijalo in Sikkimese-Tibetan, is a creeping herb grown in tropical and subtropical regions of the world. It is used by ethnic groups of Sikkim, North-East India, for the treatment of various diseases including diabetes. This study aimed to investigate the antidiabetic effect of methanol extract from D. cordata leaf (DCME) in streptozotocin (STZ) and nicotinamide (NA)-induced type 2 diabetes in rats. Diabetic Wistar albino rats were treated with DCME at 200 mg/kg and 400 mg/kg orally for 28 days. Metformin (150 mg/kg b.w.) was used as a reference drug. Fasting blood glucose (FBG) level; serum biochemical parameters; and liver, kidney, and antioxidant parameters were estimated, and pancreatic histopathology was performed after 28 days of treatment. Administration of DCME to STZ-NA-induced diabetic rats at 200 mg/kg and 400 mg/kg orally for 28 days exhibited statistically significant (P < 0.05) and dose-dependent reduction of FBG, glycosylated hemoglobin, serum lipid, and hepatorenal antioxidative parameters in DCME-treated groups when compared to those of diabetic controls. Histopathological studies of pancreas in DCME-treated rats showed improvement in β-cell density compared to diabetic group. The results demonstrate the significant antidiabetic potential of D. cordata leaf in albino rats plausibly by reducing oxidative stress and serum lipids levels, justifying the folkloric use of this plant in the treatment of diabetes.

Cashew nuts (Anacardium occidentale L.) decrease visceral fat, yet augment glucose in dyslipidemic rats

The objective of this study was to evaluate the biological effects of roasted Cashew nuts consumption on biochemical and murinometric parameters in dyslipidemic rats receiving lipid supplementation. Young male rats were randomly assigned to three experimental groups (n = 10). The Control group (CONT) was treated with water, the Dyslipidemic group (DL) received a high fat content emulsion throughout the experiment, and the Dyslipidemic Cashew Nuts group (DLCN) received the same high fat content emulsion throughout the experiment, yet was treated with Cashew nuts. Body parameters, biochemical, hepatic and fecal fatty acid profiles were all evaluated. The levels of total cholesterol and triglycerides were higher in the DL and DLCN groups as compared to the control group. DLCN and CONT presented no difference in HDL levels. DLCN presented higher glycemia levels than the other groups. There was reduction of body fat in DLCN as compared to other groups, but with higher accumulations of liver fat. DLCN presented a reduction in saturated hepatic fatty acids of 20.8%, and an increase of 177% in relation to CONT; there was also a 21% in increase DL for ω9 fatty acids in comparison to CONT. As for fecal fatty acids, there was a lower concentration of polysaturates in DLCN as compared to the other groups. The data showed that the consumption of Cashew nuts by the dyslipidemic animals treated with a hyperlipidic diet induced greater accumulations of liver fat and worsened glycemic levels, despite having reduced visceral fats and increased fecal fat excretion.

Antidiabetic effects of Maclura cochinchinensis (Lour.) corner heartwood extract

Background and aim

Maclura cochinchinensis (MC) (Lour.) heartwood extract have been used traditionally to treat diabetes in Thailand, but their mechanism of action has not been elucidated.

Experimental procedure

This study investigated the effects of an aqueous heartwood extract of MC on α-glucosidase and α-amylase activities. Moreover, its antidiabetic effect was evaluated using an oral glucose tolerance test (OGTT) and a 28-day administration to streptozotocin (STZ)-nicotinamide (NA)-induced type 2 diabetic mice.

Results

In both OGTT and the daily oral administration for 28 days in STZ-NA-induced type 2 diabetic mice models, the extract (1,000 mg/kg) significantly decreased fasting blood glucose. This hypoglycemic effect was explained by increased insulin levels and α-glucosidase inhibition (IC₅₀:1.53 ± 0.03 μg/mL).

Conclusion

This first study on the hypoglycemic activity of MC heartwood extract indicates that it could be a potential natural remedy for type 2 diabetes.

•

Maclura cochinchinensis (MC) extract exhibits hypoglycemic activity in STZ-NA-induced diabetic mice.

•

TMorin is the major active compound found in the MC heartwood extract.

•

The antidiabetic properties of MC extract may be due to the inhibition of α-glucosidase and enhance plasma insulin level.

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 Cashew Gum (Anacardium occidentale L.) on 5-Fluorouracil-Induced Intestinal Mucositis

Intestinal mucositis is a common complication associated with 5-fluorouracil (5-FU), a chemotherapeutic agent used for cancer treatment. Cashew gum (CG) has been reported as a potent anti-inflammatory agent. In the present study, we aimed to evaluate the effect of CG extracted from the exudate of Anacardium occidentale L. on experimental intestinal mucositis induced by 5-FU. Swiss mice were randomly divided into seven groups: Saline, 5-FU, CG 30, CG 60, CG 90, Celecoxib (CLX), and CLX + CG 90 groups. The weight of mice was measured daily. After treatment, the animals were euthanized and segments of the small intestine were collected to evaluate histopathological alterations (morphometric analysis), levels of malondialdehyde (MDA), myeloperoxidase (MPO), and glutathione (GSH), and immunohistochemical analysis of interleukin 1 beta (IL-1β) and cyclooxygenase-2 (COX-2). 5-FU induced intense weight loss and reduction in villus height compared to the saline group. CG 90 prevented 5-FU-induced histopathological changes and decreased oxidative stress through decrease of MDA levels and increase of GSH concentration. CG attenuated inflammatory process by decreasing MPO activity, intestinal mastocytosis, and COX-2 expression. Our findings suggest that CG at a concentration of 90 mg/kg reverses the effects of 5-FU-induced intestinal mucositis.