Safety assessment of Cissus quadrangularis extract (CQR-300): Subchronic toxicity and mutagenicity studies

Cissus quadrangularis has been used for centuries for therapeutic and culinary purposes. Extract from this plant (CQR-300) has been claimed for its health benefits. The objective of present investigation was to delineate adverse effects, if any, of CQR-300 in subchronic toxicity, and gentotoxicity studies. In the subchronic study, Sprague Dawley rats (20/sex/group) were administered (gavage) C. quadrangularis extract (CQR-300) at dose levels of 0, 100, 1000, and 2500 mg/kg body weight (bw)/day for 90 days. No treatment related clinical signs of toxicity, mortality or changes in body weights, body weight gain or food consumption were noted. Functional observation tests and ophthalmological examination did not reveal any changes. No toxicologically significant treatment related changes in hematological, clinical chemistry, urine analysis parameters, and organ weights were noted. No treatment related macroscopic and microscopic abnormalities were noted at the end of treatment period. The results of mutagenicity studies as evaluated by Ames assay, in vitro chromosomal aberration and in vivo micronucleus assay did not reveal any genotoxicity of CQR-300. Based on the subchronic study, the no-observed-adverse-effect level (NOAEL) for C. quadrangularis extract (CQR-300) determined as 2500 mg/kg bw/day, the highest dose tested.