Antioxidant activity and hypoglycemic effect assessment of the leaves from Syzygium cumini (L. ) Skeels in Wistar rats

Syzygiumcumini(L.) Skeels wasadaptedto the climatic conditionsandsoil typesin Brazil. Its fruits, leaves andinner barkare usedin folk medicinedue to their highantioxidant, anti-inflammatory, anticarcinogenicandantidiabeticactivities mainlyassociated with the presenceof phenolic compounds. It is estimated thatat least300million peopleworldwide developdiabetesand approximately 11million peopleare carriersof the disease in Brazil.The objectiveof this workwas to evaluate thein vitro antioxidant activity, as well as thehypoglycemic actionofhydroethanolic extract(HEE), the ethyl acetate(EAF) andhydromethanolic(HMF) fractions from leavesofS.cumini(L.) Skeels in rats. All assays werecarried out in three replications. Data wereexpressed as meanSDand significance was evaluated by ANOVAand Bonferronitest (p < 0.05). The results indicatea significant(p < 0.05) total phenolcontent (207 ± 2.3GAE mg g-1) andantioxidant activity(EC50=9.05±0.170 µg mL-1) for EAF. HEE and its fractions showed no significant (p > 0.05) actionto modulateglucosebytheOGTT assayinnondiabetic micecompared to control. Thus the use of the plant against diabetes in individuals is not proven.

Does Croton Argyrophyllus Extract Has an Effect on Muscle Damage and Lipid Peroxidation in Rats Submitted to High Intensity Strength Exercise?

Many species of the genus Croton have been used for anti-inflammatory, antiproliferative, antidiabetic, and antitumor purposes. The objective was to evaluate the effect of a hydroethanolic extract (HEE) from the inner bark of Croton argyrophyllus (Euphorbiaceae) on muscle damage and oxidative stress in rats after high intensity exercise. The animals were divided into four groups: (i) the sedentary group (SV; n = 7), (ii) the exercise vehicle group (EV, n = 7), (iii) the sedentary group HEE (SHG; n = 7) composed of sedentary animals and treated with the hydroethanolic extract of C. argyrophyllus (200 mg/kg, v.o.), and (iv) the HEE exercise group (HEE; n = 7) composed of animals submitted to resistance exercise (RE) and treated with the hydroethanolic extract of C. argyrophyllus (200 mg/kg, v.o.). In the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) test, the HEE showed lower values of inhibition potential (IP%) at 39.79% compared to gallic acid, 87.61%, and lipoperoxidation inhibition at 27.4% (100 µg/mL) or 28.6% (200 µg/mL) (p < 0.001). There was inhibition in free radicals in vivo. The HEE of C. argyrophyllus partially reduced the biomarkers of oxidative stress in muscle tissue and muscular damage (creatine kinase (CK) and Lactate Dehydrogenase (LDH)) (p < 0.05) in rats, and in this sense it can be an aid to the recovery process after exhaustive efforts.