Evaluation of the estrogenic activity of Indian medicinal plants in immature rats

INTRODUCTION: The objective of the study was to evaluate the estrogenic activity of four Indian medicinal plants Saraca indica (Si), Symplocos racemosa (Sr), Cyperus rotundus (Cr), Terminalia arjuna (Ta), a marketed preparation of Si (Aśokāriṣṭa) and a combination of Si + Sr using an experimental model of estrogenicity. MATERIALS AND METHODS: After approval of the institutional animal ethics committee, 22 day old female rats (n = 54) were randomly allocated to 9 groups – Group 1 and Group 2: Vehicle controls, Group 3: Ethinyl estradiol, Group 4: Si (270 mg/kg), Group 5: Sr (270 mg/kg), Group 6: Cr (540 mg/kg), Group 7: Ta (270 mg/kg), Group 8: Ashokarishta (4 ml/kg), Group 9: Si + Sr (135 mg/kg). Variables studied were: Body weight, uterine weight, relative uterine weight, presence of vaginal opening, histomorphology of the uterus and total uterine glycogen content. Parametric data were analyzed using one-way ANOVA and the categorical data were analyzed using Chi-square test. RESULTS: All animals in the ethinyl estradiol group showed a significant change in all the variables. None of the individual test drugs, neither the marketed preparation produced change in any of the variables. The plant drug combination also did not produce a change in any of the variables studied except in histomorphology wherein it caused a slight increase in the height of the luminal epithelium of the uterus (P < 0.05 vs. Group 1). CONCLUSION: The plant drugs Si, Sr, Cr, Ta and Aśokāriṣṭa did not demonstrate estrogenic activity in the immature rat model. The plant drug combination Si + Sr showed questionable estrogenic activity which needs to be evaluated in further studies.