Diabetes mellitus is a global medical and social issue. In the developed countries of the world, from 5 to 12% of the population are diagnosed with diabetes mellitus and, according to WHO prognosis, the level of this disease may increase to 30-35%. Type 2 diabetes is a disease that progresses over time, but the rational and systematic use of hypoglycemic synthetic drugs and phytopreparations can significantly delay the onset of insulin therapy. A promising source of BAS with a hypoglycemic effect is the raw material of plants of the Heather family, namely, bearberry leaves. However, on the Ukrainian market there are no domestic galenic and novo-galenic preparations based on biologically active substances of this raw material, which indicates the prospects for the development of new drugs, including those with hypoglycemic action. The aim. The aim of the study was to study the phytochemical composition and to carry out a screening of the hypoglycemic activity of dry extracts from bearberry leaves modified with various amino acids to identify promising substances with hypoglycemic action. Materials and methods. The objects of the study were 11 dry extracts from bearberry leaves, 10 of which were modified with various amino acids. The study of the phenolic compounds of the extracts was carried out by TLC, HPLC, and spectrophotometry. To assess the hypoglycemic activity of the extracts, two experiments were carried out - primary screening and oral glucose tolerance test. Results. Using TLC and HPLC, in the extracts obtained arbutin, gallic acid, 5 flavonoids were identified, among which hyperoside was dominant, 4 hydroxycinnamic acids, among which chlorogenic and caffeic acids were dominant, and their content was established. In the extracts obtained, main groups of phenolic compounds were quantified using a spectrophotometric method. Dry extracts from bearberry leaves, modified with cysteine, arginine and glutamic acid, showed the strongest hypoglycemic activity. Conclusions. The chemical composition of phenolic compounds and the hypoglycemic activity of dry extracts from bearberry leaves modified with 10 different amino acids were determined. The most promising substances turned out to be extracts modified with cysteine, arginine and glutamic acid; therefore, they are promising agents for the development of new drugs.
Introduction. In recent decades, diabetes mellitus type 2 (DM2) has become one of the leading causes of deaths worldwide. A number of studies confirmed the causal relationship between the development of insulin resistance (IR) and DM2. At the same time, traditionally and for many years the plants or substances isolated from them have been using in the DM2 treatment and correction of its complications. The aim of the study – to find out the effect of ethanolic polyphenol Bearberry leaves (Arctostaphylos uva-ursi) extract enriched with arginine (PE50_arg) on tolerance to glucose and lipid metabolism under experimental IR in rats. Research Methods. Adult male outbred albino rats were used in the present study. Two experimental IR models were conducted: daily intraperitoneal administration of dexamethasone and a diet enriched with fructose. Treating was performed by oral administration of polyphenolic alcohol extract (PE50) and the corresponding extract with the addition of arginine (PE50_arg). IR was confirmed by measuring immunoreactive insulin (IRI) and plasma glucose levels. At the end of the experiment, the lipid profile was investigated in the obtained serum samples. The statistical processing of the data was carried out using the STATISTICA program (StatSoftInc., USA, version 6.0). Results and Discussion. A diet for 7 weeks enriched with fructose caused IR in rats. Also we observed increased triacylglycerol (TAG), free fatty acids (FFA) and cholesterol (Ch) levels. Daily injections of dexamethasone, which maintained the hormone level for 5 weeks, led to the IR development. Under hormone-induced IR also FFA and TAG levels were elevated, but Ch concentration in blood plasma did not significantly change. Both extracts, PE50 and PE50_arg, improve cell sensitivity to insulin in experimental IR models. At the same time, PE50_arg has a more pronounced normalizing effect on the lipid parameters being investigated. Conclusions. Our results suggest that PE50_arg may be a potentially promising anti-diabetic agent.
Bearberry (Arctostaphylos uva-ursi L.) is a perennial plant of the heather family (Ericaceae). The leaves are dominated by arbutin, phenol carbonic acids flavonoids, saponins, etc. It was previously shown that the bearberry leaves extract reduced blood glucose level in healthy animals under glucose overload, so it need to be studied more detail. The aim of the study was to investigate the chemical composition and the effect of dry alcohol extract from bearberry leaves, which enriched with cysteine, on the rats pancreas under experimental dexamethasone-induced insulin resistance (IR). Arctostaphylos uva-ursi L. leaves extract and its modified cysteine preparation were obtained according to the developed method with 50% ethanol solution. Their phytochemical profile, hypoglycaemic and pancreatic protective effect were investigated. Phenologlycoside (arbutin), phenolic carboxylic acid (gallic acid), 5 flavonoids and 4 hydroxycinnamic acids were identified and quantified in the extracts by HPLC. Present data revealed that bearberry leaves alcoholic dry extract enriched with cysteine has a hypoglycaemic and pancreatic protective effect in treated animals under dexamethasone-induced IR model. Treatment improved hyperglycaemia, insulin resistance and beta cell reduction induced by dexamethasone injections. Graphical Abstract
Topicality. The metabolic syndrome is pathogenetically interrelated metabolic disorders in the condition of a sick person. A large set of factors is involved in its occurrence. Risk factors include genetic predisposition, overeating, insulin resistance, obesity, bad habits, hypodynamics, stress and unfavorable environmental conditions. First of all, defects of the lipid and carbohydrate metabolism provoke a cascade of genetic, metabolic, hormonal, nervous, inflammatory and other reactions and disorders in cells, tissues and organs, causing the metabolic syndrome and associated diseases, such as diabetes, kidney and gallstone disease, hypertension, platelet hyperaggregation, etc. Therefore, the rational use of synthetic and herbal medicines in the complex correction of these disorders can slow down the development of the metabolic syndrome. Aim. To develop the method for obtaining a dry modified extract from bearberry, study its chemical composition, hypoglycemic and hypolipidemic activity in order to determine the prospects of its use for the correction of the metabolic syndrome. Materials and methods. The study object was a dry extract of bearberry leaves modified with cysteine. HPLC and spectrophotometry were used to analyze the extract obtained. The hypoglycemic and hypolipidemic activity of dry extracts of bearberry was studied in rats with insulin resistance. Results and discussion. The method for obtaining a dry modified extract from bearberry leaves was developed by adding cysteine. Phenologlycoside (arbutin), 2 phenolic acids (gallic and ellagic), 6 flavonoids, 8 saponins were identified in the extract, and their quantitative content was determined. Hyperoside and catechin were dominant among flavonoids, and ursolic acid, uvaol, and lupeol prevailed among saponins. The content of the main groups of phenolic compounds was determined in the extract by spectrophotometry. The introduction of the dry extract from bearberry leaves modified with cysteine has a normalizing effect on metabolic disorders on the background of a high-fructose diet; therefore, it can be a promising agent for the correction of the metabolic syndrome. Conclusions. As a result of the research conducted, a new dry extract from bearberry leaves modified with cysteine has been created. The phytochemical composition, hypoglycemic and hypolipidemic activities of the extract have been studied, indicating the prospects for its use to correct the metabolic syndrome.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.