Protective effects of three selected standardized medicinal plant extracts used in Sri Lankan traditional medicine in adriamycin induced nephrotoxic Wistar rats

Ethnopharmacological relevance: Abelmoschus moschatus Medik. (family: Malvaceae), Asparagus falcatus (family: Asparagaceae) and Barleria prionitis Linn. (family: Acanthaceae) have been used in the treatment of kidney diseases in Sri Lankan traditional medicine. Besides the traditional use, scientific scrutinization of safe therapeutic use of these medicinal plants in the management of kidney diseases has not been reported to date.

Aim of the study: The three selected doses of the aqueous extracts of the selected medicinal plants were studied for their protective effects against adriamycin (ADR) induced nephrotoxicity in Wistar rats.

Materials and methods: Chemically standardized plant materials were used in the study. The nephroprotective activity of the lyophilized powder of the aqueous refluxed (4hr) leaf extracts of A. moschatus, A. falcatus and the whole plant extract of B. prionitis was investigated in adriamycin (20 mg/kg, ip) induced nephrotoxicity in Wistar rats (n = 6/group). The treatment regimens were initiated 24 h after the induction of nephrotoxicity and continued daily as a single dose for three consecutive days at three selected doses (200, 400 and 600 mg/kg). Fosinopril sodium (0.09 mg/kg) was used as the standard drug. Nephroprotective activity was assessed by estimating the selected biochemical parameters and by the assessment of histopathology on H and E stained sections of the kidney.

Results: The plant extracts at the three selected doses significantly attenuated the elevations in serum creatinine, blood urea nitrogen and the loss of urine total protein in a dose related manner in ADR induced nephrotoxic rats (p < 0.001). The serum concentration of albumin and total protein increased significantly (p < 0.001). Histopathological findings corroborated the biochemical evidence of nephroprotective activity. The aqueous extracts of the three selected medicinal plants exerted a relatively high antioxidant activity in vitro.

Conclusions: Evaluation of the protective effects based on biochemical parameters and histopathology assessment revealed that the aqueous leaf extracts of A. moschatus, A. falcatus and the whole plant extract of B. prionitis possess significant nephroprotective activity against ADR induced acute nephrotoxicity. The secondary metabolites present in the plant extracts may attribute to the total antioxidant activities of the selected medicinal plant extracts thereby exerting protective effects against nephrotoxicity in Wistar rats.