Evaluation of anticancer activity of the alkaloid fraction of Alstonia scholaris (Sapthaparna) in vitro and in vivo

Abstract

The anticancer effect of various doses of an alkaloid fraction of Sapthaparna, Alstonia scholaris (ASERS), was studied in vitro in cultured human neoplastic cell lines (HeLa, HepG(2), HL60, KB and MCF-7) and in Ehrlich ascites carcinoma bearing mice. Treatment of HeLa cells with 25 microg/mL ASERS resulted in a time dependent increase in the antineoplastic activity and the greatest activity was observed when the cells were exposed to ASERS for 24 h. However, exposure of cells to ASERS for 4 h resulted in 25% viable cells and hence this time interval was considered to be the optimum time for treatment and further studies were carried out using this time. Treatment of various cells with ASERS resulted in a concentration dependent decline in the viable cells and a nadir was reached at 200 microg/mL in all the cell lines studied. The IC50 was found to be 5.53, 25, 11.16, 10 and 29.76 microg/mL for HeLa, HePG2, HL60, KB and MCF-7 cells, respectively. Similarly, administration of ASERS, once daily for 9 consecutive days to the tumor bearing mice caused a dose dependent remission of the tumor up to 240 mg/kg body weight, where the greatest antitumor effect was observed. Since 240 mg/kg ASERS showed toxic manifestations, the next lower dose of 210 mg/kg was considered as the best effective dose, in which 20% of the animals survived up to 120 days post-tumor-cell inoculation as against no survivors in the saline treated control group. The ASERS treatment resulted in a dose dependent elevation in the median survival time (MST) and the average survival time (AST) up to 240 mg/kg ASERS and declined thereafter. The surviving animals were healthy and disease free. The effect of ASERS was better than cyclophosphamide, which was used as a positive control, where all the animals succumbed to death by 40 days and the MST and AST were 19.5 and 18.3 days, respectively. The effective dose of 210 mg of ASERS was 3/10 of the LD50 dose, which increased the MST and AST up to 54 and 49.5 days, respectively.