Background: The incidence of diabetes is increasing rapidly in world wide. It produces disturbances in the metabolism of carbohydrate, protein, and lipid. Evidences recommended that the natural medicines originating from plant source may represent a culturally relevant complementary treatment for diabetes. Objective: The aim of the present study is to investigate the antioxidant activities of the ethanolic leaf extract of Psidium guajava Linn. in streptozotocin (STZ) induced oxidative stress in rats. Methods: Oxidative stress is induced with a single dose of STZ 60 mg/kg b.w. and then the animals are treated with a dose of various concentrations of ethanolic leaf extract of P. guajava (100 mg/kg b.w, 200 mg/kg b.w, and 300 mg/ kg b.w) for 45 days. After the treatment, the glucose, lipid peroxides (LPO), reduce glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), urea and creatinine levels are determined. Glibenclamide is used as a standard drug (3 mg/kg b.w.). Results: The present study exposed that the administration of ethanolic leaf extract of P. guajava showed a significant decrease in glucose and LPO levels. The treatment also finds that the significant increase in GSH, GPx, SOD and CAT levels in the liver, when compared with diabetic control rats. Conclusion: The results proved that the ethanolic leaf extract of P. guajava treated group may effectively regulate the antioxidant status in STZ induced diabetic treated groups.

Free radicals which induces the oxidative stress, it induces the cellular damages in macromolecules such as protein, DNA and lipids. The uncontrolled production of free radicals which causes the various diseases such as rheumatoid arthiritis, cirrhosis, diabetes, cancer, cardiovascular diseases, aging etc. Antioxidants have been reported to prevent the oxidative damages through radical scavenging and chelating metal ions. Some synthetic drugs are available but it causes the various side effects in human body. Some natural products have antioxidative materials in their extracts and it prevents the oxidative damages. Psidium guajava is one of the important plant in the Myrtaceae family. It reported that the extracts have a various activities like antibacterial, antimalarial, antidiarrhoeal, antihyperglycemic etc. The aim of this review to compile the data of the antioxidant activity of P. guajava extract in a recent years.

Cardiovascular disease (CVD) and its complications have been regarded as the leading cause of morbidity and mortality. The drugs available in the market are effective to treat CVD, but with many adverse reactions. Nowadays, herbal products are the attention of researchers because of their less adverse effects. In this study, the cardioprotective effects of ethanolic leaves extract of Psidium guajava Linn. (Guava) (P. guajava) were evaluated in streptozotocin (STZ)-treated animal models. Mice acquired for the study were divided into five groups, each consisting of six mice. The toxin-induced mice were treated with the ethanolic leaves extract of P. guajava (300 mg/kg body weight [b.w.]). The results were compared to the standard drug (glibenclamide)-treated mice (3 mg/kg b.w.). The following parameters were considered for further investigations: creatine kinase-muscle brain (CK-MB), creatine kinase (CK), troponin, lysosomal, and mitochondrial enzymes. Then the docking study was accomplished. The levels of cardiac marker enzymes and lysosomal enzymes increased significantly in the toxin-induced mice, while the level of mitochondrial enzyme decreased significantly. During treatment with the ethanolic leaves extract of P. guajava, the levels of all parameters were notably reversed to normal range (P < 0.05). Further, in docking analysis, the interaction of compounds, such as alpha-terpineol, cyclopentanecarboxamide, guaiol (a sesquiterpenoid alcohol), 1H-cyclopropanaphthalene, tetracyclotridecan-9-ol, dormin/abscisic acid, and epiglobulol, with the respective protein molecules, evidenced the cardioprotective effect of P. guajava leaves. Hence, it was concluded that the ethanolic leaves extract of P. guajava leaves have a cardioprotective effect.

The cardio-protective effects of Terminalia catappa and Terminalia chebula are well-recognized in Ayurveda for its antimicrobial, antidiabetic and antioxidant potentials. The present study evaluate...

The present study aims to investigate the protective effect of Euphorbia thymifolia and Euphorbia hirta extracts on in vitro antioxidant activity and in vivo analysis on hepatic marker enzyme level...

This study was conducted to find out the anti-diabetic and hypolipidemic potential of ethanolic extract of Psidium guajava Linn leaves and its one of the important compound of caryophyllene in a streptozotocin (STZ) induced diabetic rats. The rats were divided into eight groups. Diabetes was induced by STZ at a dosage of 60 mg/kg b.w. The various dosages of extract (100, 200, 300 mg/kg b.w), caryophyllene (300 mg/kg b.w) were injected and glibenclamide (3 mg/kg b.w) is used as a standard drug. After the treatment of the extract and caryophyllene the levels of blood glucose, HbA1c, glucose-6-phosphatase, fructose-1,6-bis phosphatase, total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), high density lipoprotein (HDL) were determined. Pancreatic tissue changes were noticed in all the groups. The present study showed that there was a significant reduction in blood glucose, HbAlc, glucose-6-phosphatase, fructose-1,6-bis phosphatase, TC, TG, LDL, VLDL and the enhancement was noticed in the level of insulin, glucokinase and HDL. Pancreas was damaged in diabetic induced rats and it altered to normal size and shape in the plant extract treated and caryophyllene treated groups. The results proved that the STZ induced diabetic rat models had revealed anti-diabetic and hypolipidemic effect treated with ethanolic leaf extract of P. guajava and caryophyllene.