Subchronic toxicity study of herbal tea of Moringa stenopetala (Baker f.) Cudof. and Mentha spicata L. leaves formulation in Wistar albino rats

Moringa stenopetala (Baker f.) Cudof. and Mentha spicata L. are widely used in the traditional system of medicine for the treatment of diabetes, hypertension, digestive problems and various disorders. The leaves formulation of M. stenopetala and M. spicata herbal tea showed better antidiabetic and antihypertensive effects in rodent models. However, its long-term safety profile has not been investigated yet. Thus, this study investigated the subchronic (90 days) oral toxicity of the leaves formulation of M. stenopetala and M. spicata herbal tea in Wistar albino rats. Four groups of rats (n = 10, with 5/sex/group) were randomly assigned into a control (vehicle) group and three test groups (559.36, 1118.72 and 2237.44 mg/kg, respectively). The three test groups received the herbal tea of M. stenopetala and M. spicata leaves blend daily for 90 days. The control group received distilled water. During the treatment period, clinical signs were observed daily, and food consumption and body weight changes of the rats were measured weekly. At the end of the experiment, macro-pathological, hematological and biochemical parameters were evaluated. Furthermore, histopathology of liver, kidney, heart, stomach and pancreas were examined. Subchronic oral administration of the herbal tea of M. stenopetala and M. spicata leaves blend did not result in death or significant toxicity signs in the treated group rats. Moreover, the herbal tea caused no significant changes on body weight, food intake, organ weight, hematological and biochemical parameters in either sex. However, the serum AST, CK and LDH levels were significantly elevated in rats treated with 2237.44 mg/kg of herbal tea in both sexes. There was no significant alteration in the histology of organs, only minor lesions in the liver, kidney and pancreas were observed. The study results indicate that the herbal tea of M. stenopetala and M. spicata leaves blend is relatively safe/low toxic to rats in subchronic exposure. However, further preclinical (chronic, teratogenic, reproductive and developmental toxicity) studies in animals are required in order to have sufficient safety and toxicity profiles for its use in humans.