Methanolic Bark Extract of Abroma augusta (L.) Induces Apoptosis in EAC Cells through Altered Expression of Apoptosis Regulatory Genes

Abstract

Abroma augusta (L.), one of the herbal medicinal plants, is widely used for treatment of various maladies. The present study was initiated to determine the antioxidant, hemolytic, cytotoxicity, and anticancer activities of methanolic extract from the bark of the plant. The phytochemical screening was done by analyzing different phytochemicals present in the extract. We observed the presence of alkaloids, steroids, terpenoids, flavonoids, reducing sugars, and glycosides in the bark extract which showed the highest antioxidant capacity. Antioxidant potential of the methanolic extract was evaluated in vitro by DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging assay method. This extract showed prominent scavenging activity with IC₅₀ value of 38.65μg/ml. The hemolytic activity of the extract was evaluated at concentrations ranging from 250 to 1000μg/ml. It was observed that the extract induced hemolysis percentage of 9.41 to 4.1, which implies that the extract has no potent hemolytic activity. Cytotoxicity and anticancer activities were observed on Ehrlich ascites carcinoma (EAC) cells. In addition, the bark showed promising cytotoxicity with IC₅₀ value of 329.41μg/ml, and the study indicated that the extract was capable of inhibiting EAC cell growth by 75.5 when administered at 100mg/kg/day body weight intraperitoneally for five consecutive days to Swiss albino mice. Morphological change of apoptotic cell was determined by fluorescence and optical microscopy. DNA fragmentation is another marker for apoptosis, and the bark extract-treated EAC cells showed smeared and fragmented DNA bands. Apoptosis correlated well with the upregulation of p53 and Bax and also with the downregulation of NF-κB and Bcl-2. Furthermore, activity and interaction of two A. augusta compounds were tested through molecular docking simulation study. In conclusion, our results suggest that A. augusta bark has the potential to be considered as an anticancer agent.