Figure 5. Effect of Tβ4 on antioxidant and antiapoptotic genes under siRNA knock down of catalase, Cu/Zn-SOD and Bcl₂ genes in cardiac fibroblasts under normal and oxidative stress condition.

Representative western blot illustrating the restoration of the expression of catalase, Cu/Zn-SOD and Bcl₂ in the cardiac fibroblasts upon knockdown of antioxidant and antiapoptotic genes, viz., (A) siRNA-catalase vs. (B) scrambled siRNA; (C) siRNA-Cu/Zn-SOD vs. (D) scrambled siRNA and (E) siRNA-Bcl₂ vs. (F) scrambled siRNA, respectively. (G and H) GAPDH was used as an internal loading control for the above experiments. (I) Effect of Tβ4 on antioxidant and antiapoptotic genes under control and siRNA knock down of catalase, Cu/Zn-SOD and Bcl₂ genes in cardiac fibroblasts under normal and oxidative stress condition. Data represent the means±SE of at least three separate experiments. Clear bars represent the normalized protein expression of respective proteins in the si-scrambled RNA condition while the color bars represent the normalized protein expression under the respective siRNA knockdown conditions. * denotes p<0.05, compared to si-scramble control, ^# denotes p<0.05, compared to si-scramble and H₂O₂ treated group, ** denotes p<0.05, compared to si-RNA control group and ^## denotes p<0.05, compared to the respective si-RNA and H₂O₂ treated group while ^@ denotes p = ns, compared to si-RNA and H₂O₂ treated group. (J) Bar graph shows relative fold-change in the mRNA expression of caspase-3 in Tβ4 pretreated cardiac fibroblasts under respective siRNA knockdown and H₂O₂ induced oxidative stress. Data represent the means±SE of at least three separate experiments. * denotes p<0.05, compared to controls while ^# denotes p<0.05 compared to the H₂O₂-treated group.