Evaluation of anti-diabetic effects of phytochemicals from urtica dioica (stinging nettle),salvia officinali(sage),Psidium(Guava) and citrus limon(lemon) using an experimental mice model

Abstract

Diabetes mellitus affects millions of people Worldwide. In developing countries, diabetes mellitus causes significant morbidity and mortality to both children and adults. Although extensive research has been conducted on diabetes mellitus, effective treatment has not yet been reported. Oral anti-diabetic drugs and insulin used in clinical management are expensive, unavailable or have side effects. Therefore, there is need for safer and effective bio-active drugs from medicinal plants. The aim of this study was thus to investigate the anti- diabetic efficacy of phytochemicals from Urtica dioica, Salvia oflicinalis, Psidium guajava and Cirrus limon leaf extracts. Three months old fresh leaves of the plants were collected from Egeflon University’s Botanical Garden for extraction of phytochemicals. Methanol Was used as the primary solvent for extraction. The resultant plants extracts were partitioned with Water, ethyl acetate and hexane and concentrated using a rotary vacuum evaporator to obtain ethyl acetate, hexane, and aqueous crude extracts. Diabetes was induced in the experimental mice using a single intraperitoneal injection of alloxan monohydrate at a dose of 200 mg/kg body Weight. The crude extracts Were subjected to preliminary in vivo bio-assays for 7 days Where they Were administered orally to experimental mice. Ethyl acetate extract of S. oflicinalis and methanol extract of C. limon did not reveal any anti-diabetic effect while the aqueous extract of S. Qflicinalis showed significant hypoglycemic effect, p< 0.05 compared to other extracts. It Was, therefore, subjected to further hypoglycemic studies Where fasting blood sugar and live Weights of various groups were monitored at intervals of 72 hours for 15 days. There was a significant drop in blood sugar levels of the groups treated With S. ojficinalis aqueous extract at 400 mg/kg and 600 mg/kg dosage levels from 452.00 zk 11.13 Mg/dl and 431.00 :1: 10.65 Mg/dl to 256.33 :1: 5.12 Mg/dl and 256.67 :1: 8.74 Mg/dl and Weight gain improvement from 28.05 i 0.39 g and 27.38 i 0.52 g to 29.32 i 0.42 g and 28.55 zt 0.38g respectively compared to controls, p< 0.05. Histopathological analysis of liver and kidney tissues obtained from euthanized mice did not reveal any significant changes compared to the controls. This indicated that the extracts did not confer adverse effects on these tissues. Phytochemical tests of the extracts revealed presence of flavonoids, sterols, saponins, tannins, alkaloids, and triterpenes. Flavonoids and triterpenes particularly have been documented to possess anti-diabetic effects on alloxan induced mice. Results from this study indicate that U. dioica, S. ojjficinalis, C. limon and P. guajava extracts are potential anti-hyperglycemic and can be used in modulating blood glucose with exception of ethyl acetate extract of S. oflicinalis and methanol extract of C. limon.