Assessment of the influence of the mineral complex of rutin on the degree of expression of anti-diabetic activity

Introduction. Type 2 diabetes mellitus is currently considered one of the most common non-communicable diseases. For the prevention and concomitant treatment of this pathology, various herbal remedies are successfully used, such as, for example, blueberry shoots. The plant contains phenolic compounds (anthocyanins, flavonoids, phenolcarboxylic and organic acids), which have antioxidant and hypoglycemic effects, and also accumulates macro- and microelements (Ca, Mg, Zn, Mn), which in turn can affect the course of diabetes mellitus. Complexes of elements with phenolic biological active substances (BAS) can affect the formation of a pharmacological response or change its severity. Therefore, it is possible to put forward a hypothesis about the potentiation of the antidiabetic action of phenolic compounds when they exist in the form of mineral complexes.Aim. To carry out a comparative assessment of the antidiabetic activity of the mineral complex rutin with zinc in comparison with precursor substances and extraction from blueberry shoots to predict the effect of elements on the course of this pathology.Materials and methods. The objects of the study were an aqueous solution (C = 0.18 mg/ml) of a model complex of rutin with zinc with a molar ratio of components of 1 : 1 and blueberry shoots purchased from a pharmacy in St. Petersburg. According to the information on the packaging, the region of raw material procurement is Altai Territory, Barnaul, the period for harvesting blueberries is July 2020. The complex of rutin with zinc was obtained according to the method described in the literature from the pharmaceutical substance rutin (Rutin, batch 332, valid until 26.03.2023, Sichuan Guangsong Pharmaceutical Co., Ltd., China, FS 000569-060514) and an aqueous solution (С = 0.13 mg/ml) zinc chloride (Zinc chloride, batch 39/G 4, valid until 09.10.2021, Neva Reaktiv, Russia, STP TU COMP 1-533-2012). The optimal ratio of components 1 : 1 for the formation of a mineral complex was established by us earlier experimentally using the Job's method. The mass of zinc chloride, which must be added to the extraction, and the mass of the complex for the preparation of its aqueous solution were calculated on the basis of the quantitative content of biologically active substances in blueberry shoots and the molar ratio of the components involved in the formation of the complex compound determined by the spectral method. The quantitative content of the main groups of biologically active substances (flavonoids, hydroxycinnamic acids, organic acids) was determined spectrophotometrically on SF-2000 instrument (Russia) and titrimetrically using the methods presented in Russian Pharmacopoeia XIV FS.2.5.0093.18 and FS.2.5.0012.15. The antidiabetic effect of the complex of rutin with zinc was evaluated in comparison with an aqueous extract from the shoots of common blueberries (the ratio of raw materials: extractant – 1 : 80), an aqueous solution of zinc chloride (concentration – 0.36 mg/ml) and their mixture (ratio 1 : 1) on a model of dexamethasone-induced type 2 diabetes mellitus in laboratory animals. Determination of blood glucose concentration was carried out using a portable glucometer "AccuChek Active" (Roche Diabetes Care, Germany). The presence of glucosuria and ketonuria was established using Ketoglyuk-1 test strips (Biosensor AN, Russia). Statistical processing of the results was carried out using the Microsoft Excel program according to OFS.1.1.0013.15.Results and discussion. The results of the content of glucose and ketones in urine showed that in the process of modeling diabetes mellitus, glucosuria and ketonuria are characteristic for all groups of animals, which confirmed the formation of a pathological process in rats. A lower content of glucose and ketones in urine was found in a group of animals that received a complex of rutin with zinc (glucose concentration – less than 2.3 mmol/l, ketone concentration – less than 0.2 mmol/l). Measurement of the concentration of glucose in the blood showed that the complex of rutin with zinc has the most pronounced hypoglycemic effect, while the water extract from blueberry shoots and an aqueous solution of zinc chloride have a minimal antidiabetic effect (blood glucose is 6.9 mmol/l versus 8,1 mmol/l and 7.9 mmol/l, respectively).Conclusion. The study of the influence of elements in the composition of phenolic complexes on the course of diabetes mellitus showed that the introduction of minerals has a positive effect on the severity of the pharmacological effect, which can serve as confirmation of the hypothesis about the potentiation of the antidiabetic effect of phenolic compounds when they exist in the form of mineral complexes. Thus, the complex of rutin with zinc showed the maximum activity in comparison with the solution of zinc chloride, extraction from blueberry shoots and their mixture, which suggests that the form of existence of natural phenolic compounds in the composition of mineral complexes is optimal both from the point of view of accumulation and from the side manifestations of a pharmacological response. The results of the study create the preconditions for further study of the effect of various elements in combination with marker phenolic components of antidiabetic herbal preparations on the course of diabetes mellitus, and also make it possible to conclude that natural mineral complexes have a prophylactic effect against this pathology.

The Antidiabetic Effect of Grape Pomace Polysaccharide-Polyphenol Complexes

Type 2 diabetes mellitus (T2DM) is one of the most prevalent chronic metabolic diseases of the 21st century. Nevertheless, its prevalence might be attenuated by taking advantage of bioactive compounds commonly found in fruits and vegetables. This work is focused on the recovery of polyphenols and polysaccharide–polyphenol conjugates from grape pomace for T2DM management and prevention. Bioactives were extracted by solid–liquid extraction and by pressurized hot water extraction (PHWE). Polyphenolic fraction recovered by PHWE showed the highest value for total phenolic content (427 mg GAE.mg−1), mainly anthocyanins and proanthocyanidins, and higher antioxidant activity compared to the fraction recovered by solid–liquid extraction. Polysaccharide–polyphenol conjugates comprehended pectic polysaccharides to which approximately 108 mg GAE of phenolic compounds (per mg fraction) were estimated to be bound. Polyphenols and polysaccharide–polyphenol conjugates exhibited distinct antidiabetic effects, depending on the extraction methodologies employed. Extracts were particularly relevant in the inhibition of a-glucosidase activity, with free polyphenols showing an IC50 of 0.47 mg.mL−1 while conjugates showed an IC50 of 2.7, 4.0 and 5.2 mg.mL−1 (solid–liquid extraction, PHWE at 95 and 120°C, respectively). Antiglycation effect was more pronounced for free polyphenols recovered by PHWE, while the attenuation of glucose uptake by Caco-2 monolayers was more efficient for conjugates obtained by PHWE. The antidiabetic effect of grape pomace bioactives opens new opportunities for the exploitation of these agri-food wastes in food nutrition, the next step towards reaching a circular economy in grape products.

Antidiabetic Activity of Gomphogyne bonii Gagnep. Extract against High-Fat Diet and Alloxan-Induced Type 2 Diabetes in Mice

So far, diabetes mellitus has become a health threat to society all over the world. Especially, people with diabetes have always coped with complications related to this disease and unexpected side effects of synthetic drugs. Thus, there has been a current trend for researchers to find out new natural ingredients which were safer and still effective in the treatment of diabetes. Gomphogyne bonii Gagnep. extract (G. bonii extract) was an herbal-derived product of the Pharmacy Department, Vietnam University of Traditional Medicine. This study was designed to assess the antidiabetic effect of G. bonii extract on a high-fat diet (HFD) and alloxan-induced diabetes in mice. Mice were first fed a high-fat diet for 8 weeks and then given an intraperitoneal injection of alloxan (ALX) at the dose of 180 mg/kg b.w. After the diabetic mice model was successfully established, mice were administered orally with G. bonii extract at two doses of 4 mL/kg b.w/day and 12 mL/kg b.w/day for 2 weeks. The results revealed that G. bonii extract at both doses ameliorated the effects of ALX on the concentration of glucose, total cholesterol (TC), triglyceride (TG), and low-density lipoprotein-cholesterol (LDL-C) and microhistological images of livers. Besides, the antidiabetic effect of G. bonii extract at the dose of 12 mL/kg b.w/day was better than that at the dose of 4 mL/kg b.w/day. This suggested that G. bonii extract could be a potential agent for treating diabetes mellitus in clinical practice.

Trace Mineral, Qualitative Phytochemical Composition and Antidiabetic Effect of Ethanol Extract of Citrullus lanatus Seeds on Diabetic Rats

The trace mineral concentration, phytochemical composition and antidiabetic effect of the ethanol extract of C. lanatus seeds were carried out using standard methods. The preclinical experimental model was 120 mgkg-1 b.w. (via intraperitoneal) Alloxan induced diabetic rat model, with ethanol extract of C. lanatus seeds administered orally at 500mgkg-1 b.w. Qualitative phytochemical screening showed presence of alkaloids, flavonoids, saponins, cardiac glycosides, steroids/triterpenoids, tannins, carbohydrates and oils. Atomic Absorption Spectrophotometric analysis revealed that iron had the highest value (8.31mgkg-1), followed by zinc (5.78 mgkg-1), then manganese (4.28 mgkg-1). Selenium concentration was appreciable (0.85 mgkg-1). Ethanol extract of C. lanatus seeds significantly (p < 0.05), dose and time dependently reduced blood glucose level, increased body weights of rats and had positive effect on organ weights and organ volume. The results in this study showed that Citrullus lanatus seeds are rich in zinc, selenium, manganese, iron, alkaloids, flavonoids, saponins, cardiac glycosides, steroids/triterpenoids, and tannins. They may therefore serve as good sources of these trace mineral nutrients and bio actives for nutritional and medicinal purposes relating to diabetes management.