Effects of butanol fraction of Ziziphus mucronata root ethanol extract on glucose homeostasis, serum insulin and other diabetes-related parameters in a murine model for type 2 diabetes

Ethyl Acetate Fractions of Tectona Grandis Crude Extract Modulate Glucose Absorption and Uptake as Well as Antihyperglycemic Potential in Fructose-Streptozotocin-Induced Diabetic Rats

Type 2 diabetes (T2D) is a global health challenge with increased morbidity and mortality rates yearly. Herbal medicine has provided an alternative approach to treating T2D with limited access to formal healthcare. Tectona grandis is being used traditionally in the treatment of diabetes. The present study investigated the antidiabetic potential of T. grandis leaves in different solvent extractions, and the crude extract that demonstrated the best activity was further fractionated through solvent-solvent partitioning. The ethyl acetate fraction of the ethanol crude extract showed the best antidiabetic activity in inhibiting α-glucosidase, delaying glucose absorption at the small intestine's lumen, and enhancing the muscle's postprandial glucose uptake. The ethyl acetate fraction was further elucidated for its ability to reduce hyperglycemia in diabetic rats. The ethyl acetate fraction significantly reduced high blood glucose levels in diabetic rats with concomitant modulation in stimulated insulin secretions through improved pancreatic β-cell function, insulin sensitivity by increasing liver glycogen content, and reduced elevated levels of liver glucose-6-phosphatase activity. These activities could be attributed to the phytochemical constituents of the plant.

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.

Potential antidiabetic phytochemicals in plant roots: a review of in vivo studies

Background

Medicinal plants are used to treat various disorders, including diabetes, globally in a range of formulations. While attention has mainly been on the aerial plant parts, there are only a few review studies to date that are focused on the natural constituents present in the plant roots with health benefits. Thus, the present study was performed to review in vivo studies investigating the antidiabetic potential of the natural compounds in plant roots.

Methods

We sorted relevant data in 2001-2019 from scientific databases and search engines, including Web of Knowledge, PubMed, ScienceDirect, Medline, Reaxys, and Google Scholar. The class of phytochemicals, plant families, major compounds, active constituents, effective dosages, type of extracts, time of experiments, and type of diabetic induction were described.

Results

In our literature review, we found 104 plants with determined antidiabetic activity in their root extracts. The biosynthesis pathways and mechanism of actions of the most frequent class of compounds were also proposed. The results of this review indicated that flavonoids, phenolic compounds, alkaloids, and phytosteroids are the most abundant natural compounds in plant roots with antidiabetic activity. Phytochemicals in plant roots possess different mechanisms of action to control diabetes, including inhibition of α-amylase and α-glucosidase enzymes, oxidative stress reduction, secretion of insulin, improvement of diabetic retinopathy/nephropathy, slow the starch digestion, and contribution against hyperglycemia.

Conclusion

This review concludes that plant roots are a promising source of bioactive compounds which can be explored to develop against diabetes and diabetes-related complications.

Graphical abstract

Kolaviron attenuates cardiovascular injury in fructose-streptozotocin induced type-2 diabetic male rats by reducing oxidative stress, inflammation, and improving cardiovascular risk markers

The prevalence of cardiovascular disease among type-2 diabetic patients has become a source of major concern world over. This study explored the protective effect of kolaviron, a bioflavonoid, against oxidative cardiovascular injury in fructose- streptozotocin-induced type 2 diabetic male Sprague Dawley rats. After acclimatization, induction, and confirmation of type-2 diabetes, kolaviron was administered for 28days, after which the animals were anesthetized with Isofor and euthanized. Blood from each rat were collected, and blood samples were then centrifuged for serum and plasma. Cardiac troponin I (cTnI), creatine kinase myocardial band (CK-MB), Creatine phosphokinase (CK), and insulin levels were immediately determined in serum, while remaining samples (serum, plasma, and organs) were stored in the bio-freezer at - 80 °C and 10% formalin for enzyme-link immunosorbent assay (ELISA), biochemical, molecular, and histopathological studies. The results show that type-2 diabetes induction with fructose and streptozotocin led to increased blood glucose levels, decreased insulin levels and cardiac antioxidant enzyme activities, increased malondialdehyde levels, cardiac biomarkers and pro-inflammatory cytokines levels, resulted in abnormal lipid profile, increased blood pressure and angiotensin-converting enzyme (ACE) activity, and decreased plasma endothelial nitric oxide synthase (eNOS) concentration. The histopathological examination of the cardiac tissue revealed severe lesion, hypertrophy, and myofibrils degeneration. However, administration of kolaviron for 28days remarkably improved these conditions. Hence the result from the study validates the potency of kolaviron, and suggests it could serve as an alternative to existing remedy in ameliorating or protecting against cardiovascular injury in type-2 diabetes.

Plant Extracts for Type 2 Diabetes: From Traditional Medicine to Modern Drug Discovery

Type 2 diabetes mellitus (T2DM) is one of the largest public health problems worldwide. Insulin resistance-related metabolic dysfunction and chronic hyperglycemia result in devastating complications and poor prognosis. Even though there are many conventional drugs such as metformin (MET), Thiazolidinediones (TZDs), sulfonylureas (SUF), dipeptidyl peptidase 4 (DPP-4) inhibitors, glucagon like peptide 1 (GLP-1) and sodium-glucose cotransporter-2 (SGLT-2) inhibitors, side effects still exist. As numerous plant extracts with antidiabetic effects have been widely reported, they have the potential to be a great therapeutic agent for type 2 diabetes with less side effects. In this study, sixty-five recent studies regarding plant extracts that alleviate type 2 diabetes were reviewed. Plant extracts regulated blood glucose through the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway. The anti-inflammatory and antioxidant properties of plant extracts suppressed c-Jun amino terminal kinase (JNK) and nuclear factor kappa B (NF-κB) pathways, which induce insulin resistance. Lipogenesis and fatty acid oxidation, which are also associated with insulin resistance, are regulated by AMP-activated protein kinase (AMPK) activation. This review focuses on discovering plant extracts that alleviate type 2 diabetes and exploring its therapeutic mechanisms.

Comparison Among Garlic, Berberine, Resveratrol,Hibiscus sabdariffa, GenusZizyphus, Hesperidin, Red Beetroot,Catha edulis,Portulaca oleracea, and Mulberry Leaves in the Treatment of Hypertension and Type 2 DM: A Comprehensive Review

Diabetes mellitus (DM) and hypertension are 2 of the most prevalent diseases with poor impact on health status worldwide. In most cases, they coexist with other metabolic disorders as well as cardiac, micro- and macrovascular complications. Many plants are known for their hypotensive, cardioprotective, and/or antidiabetic activities. Their active ingredients either identified and isolated or still utilized as herbal preparations of certain plant parts. The use of medicinal plants comprises the main basis for most of the traditional medicine (TM) systems and procedures. As conventional medicines seem insufficient to control such progressive diseases, herbal agents from TM could be used as adjuvant with good impact on disease control and progression as well as other concomitant health conditions. The aim of this study is to compare the efficacy of 10 different herbal medicines of botanical origin or herbal preparations in the management of hypertension and its cardiovascular complications and type 2 DM along with various coexisting health disorders. These herbal medicines are garlic, berberine, resveratrol, Hibiscus sabdariffa, Zizyphus ( oxyphylla, mucronate, jujube, rugosa), hesperidin, red beetroot, Catha edulis, mulberry leaves, and Portulaca oleracea.

Ziziphus mucronata Willd. (Rhamnaceae): it's botany, toxicity, phytochemistry and pharmacological activities

Ziziphus mucronata is an important multi-purpose plant species that has been used in African traditional medicine for ages in the treatment of various devastating human and animal infections. The current paper is aimed at providing an overview of uses, toxicology, pharmacological properties and phytochemistry of Z. mucronata. The information used in the current work was retrieved using various search engines, including Pubmed, Science Direct, Google Scholar, Scielo, SciFinder and Scopus. The key words used included Ziziphus mucronata, secondary metabolites, chemistry, biological activity and pharmacology, anti-inflammatory, antimicrobial, antifungal, antiviral, ethnobotanical survey, medicinal uses, safety, toxicology and other related words. Out of the 46 infections which the plant species is used to treat, the most common uses includes sexually transmitted infections, skin infections, diarrhoea and dysentery, respiratory and chest complaints and gynaecological complaints (citations ≥6). Pharmacologically, the plant species exhibited a potential antimicrobial activity yielding a minimum inhibitory concentration of <1 mg/ml against important pathogens which includes Mycobacterium tuberculosis, Moraxella catarrhalis, Staphylococcus aureus, Escherichia coli, Propionibacterium acnes, Candida albicans, Cryptoccoos neoformans amongst other microorganisms. Furthermore, the extracts and compounds from Z mucronata revealed potent antiviral, antioxidant, anti-inflammatory and other activities in vitro. Phytochemically, cyclo-peptide alkaloids (commonly called mucronines) dominates and in conjunction with triterpenes, flavonoids, phenolic acids and anthocyanins. Besides these compounds, the plant species exhibited the presence of important in minerals. These phytoconstituents may well explain the reported biological activities. Although the extracts revealed no cytotoxic effect to Vero cells, further toxicological characteristics of the plant species still needs to be explored. There is also a need to carry out the comprehensive safety profiles of the plant species, including heavy metal detection. Although the plant species revealed important biological activities, which includes antimicrobial, antiviral, anti-diabetic, anti-inflammatory, anti-oxidant, anti-plasmodial, anthelmintic, and anti-anaemic activity in vitro, further research is needed to explore the in vivo studies, other compounds responsible for such activities and the mechanisms of action thereof. Such activities validates the use of the plant species in traditional medicine. The data on the possible use of the plant species in the treatment of diarrhoea, sexually transmitted infections, skin related and gynaecological complaints are scant and still needs to be explored and validated both in vitro and in vivo. Furthermore, the anticancer and anthelmintic activity of the plant species also needs to be explored.

Anti-hyperglycemic and ameliorative effect of concentrated hot water-infusion of Phragmanthera incana leaves on type 2 diabetes and indices of complications in diabetic rats

Objectives

This study investigated the anti-hyperglycemic effects of concentrated hot water infusion of Phragmanthra incana leaves as well as its ameliorative effect on indices related to diabetic complications in a type 2 diabetes model of rats.

Methods

Type 2 diabetes was induced by feeding 10% fructose solution ad libitum for two weeks followed by an intraperitoneal injection of streptozotocin (40 mg/kg body weight (b.w.)). Concentrated plant infusion was administered orally at a dose of 150 and 300 mg/kg b.w. to two type 2 diabetes rat groups. Diabetic rats without treatment served as a negative control while the group administered with metformin was served as a positive control. The intervention lasted for 4 weeks when a single oral dose was given daily for 5 days a week. Body weight and blood glucose were determined every week. An oral glucose tolerance test was performed in the last week of treatment. The rats were sacrificed after 4 weeks of intervention, and the blood and organs were harvested for further analysis.

Results

Both dosages of the plant infusion significantly improved body weight, pancreatic β-cell function (HOMA-β), insulin secretion and reduced blood glucose, insulin resistance (HOMA-IR) with concomitant reduction in the elevated level of serum α-amylase activity, fructosamine, uric acid, urea, and liver function enzymes. The liver glycogen content was significantly improved while the activity of liver glucose-6-phosphatase was significantly reduced.

Conclusion

The results demonstrate the anti-hyperglycemic ability of P. incana and its ability to delay the onset of diabetic complications which can be exploited for the anti-diabetic drug discovery.

Quercetin modulates hyperglycemia by improving the pancreatic antioxidant status and enzymes activities linked with glucose metabolism in type 2 diabetes model of rats: In silico studies of molecular interaction of quercetin with hexokinase and catalase

Quercetin was assessed for its antihyperglycemic effect in fructose-streptozotocin (STZ) induced diabetic rats. The oral administration of quercetin at the dosage of 25 and 50 mg/kg for 28 days remarkably reduced the level of blood glucose, glycosylated hemoglobin (Hb), and hepatic glycogen but enhanced plasma Hb concentration. The altered activities of glucose-6-phosphatase and hexokinase in diabetic rats were significantly improved upon quercetin treatment. Furthermore, the antioxidant activity of pancreatic superoxide dismutase, catalase (CAT), and reduced glutathione was effectively increased while the value for thiobarbituric acid reactive species was decreased. A significant reduction of glycemia was observed in the glucose tolerance test, 120 min after the glucose pulse. Also, the damage caused by fructose-STZ in the liver and pancreas of diabetic animals were restored to near normal. Molecular docking of quercetin showed a high affinity for hexokinase and CAT with a binding energy of -7.82 and -9.83 kcal/mol, respectively, more elevated than the standard drugs. PRACTICAL APPLICATIONS: Functional foods and nutraceuticals have increasingly interested the consumers in terms of health benefits and have started focussing on the prevention or cure of disease by the foods and their health-enhancing phytochemicals. Quercetin is one of the most potent naturally occurring antioxidants within the flavonoid subclasses, mostly distributed as a secondary metabolite in fruits, vegetables, and black tea. Based on the results exhibited in the present study, we proposed that the consumption of foods rich in quercetin could be a cheap and affordable nutraceutical that can be developed for the treatment of T2DM and its complications. Further studies on the safety aspects of quercetin in long-term usage are strongly recommended before implementing for the treatment of human diseases.

Inhibition of JAK-STAT and NF-κB signalling systems could be a novel therapeutic target against insulin resistance and type 2 diabetes

AIMS

Chronic inflammation is associated with the production of high levels of proinflammatory cytokines via the JAK-STAT and NF-κB signalling pathways which are known to be inhibited by tofacitinib and aspirin respectively. High levels of these cytokines increase the synthesis of suppressors of cytokines (SOCS), which at high levels inhibit insulin signalling leading to insulin resistance. The effects of tofacitinib and aspirin on the degree of insulin resistance in type 2 diabetic rats were determined.

MATERIALS AND METHODS

Rats were induced with type 2 diabetes (T2D) by administration of 10% fructose solution (ad libitum) followed by streptozotocin injection (40 mg/kg BW) and treated with different doses of tofacitinib (10 and 20 mg/kg BW), aspirin (100 and 200 mg/kg BW) and combination of the two drugs at both doses for 9 weeks.

KEY FINDINGS

Results showed that separate treatment with 10 mg/kg BW tofacitinib and 100 mg/kg BW aspirin significantly (P < 0.05) decreased tumour necrosis factor-α (TNF-α), interleukin 6 (IL-6) and serum amyloid A when compared to diabetic untreated rats. However, the combined therapy (10 mg/kg BW tofacitinib and 100 mg/kg BW aspirin) significantly decreased the levels of TNF-α, IL-6, serum amyloid A, HOMA-IR, blood glucose level and SOC-3 gene expression but significantly (P < 0.05) improved glucose homoestasis, insulin secretion, HOMA-β and GLUT-4 gene expression when compared to diabetic untreated rat.

CONCLUSION

It was concluded that simultaneous inhibition of the JAK-STAT and NF-κB signalling pathways with tofacitinib and aspirin respectively, could mitigate insulin resistance and hyperglycemia in T2D.

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.