Figure 2: Senescence associated growth arrest in B/CMBA.Ov (mouse ovarian epithelial) cells after exposure to 0.005 μM MIC. (i) Control showing percentage of cells in G1, S and G2/M phases of the cell cycle, respectively, (ii) Cells after 24 h treatment showing significant arrest in G1 phase, (iii) sustained distinct G1 arrest even after 48 h treatment, (iv) cells after 96 h treatment showing onset of aneuploidy in cells with considerable G1 arrest. (b) Senescence associated β-galactosidase activity. Representative phase contrast microphotograph (20μm) of B/CMBA.Ov cells prior to and after exposure to 0.005 μM MIC showing multiple senescent cells which display the characteristics of senescence, including increased cell size, poly-nucleation, accumulation of vacuoles and senescence-associated β-galactosidase activity expression at 24 h (small black arrows). (Inset; treated cells showing increased in accumulation of beta gal stain). (c) SIPS associated increase in cell size. Graphical plot representing flow cytometric measurement of changes in cell size after exposure to 0.005 μM MIC in B/CMBA.Ov cells in comparison to control. The representative curves correspond to (i) control untreated cells at 0 h and cells observed during 48 h (ii) and 72 h (iii) of treatment. Increase in the cellular size is implicated by the shift of the curve to the right during acquisition of senescence phenotype along the time course.