Figure 4. HO-1 gene knockdown impairs antioxidant defenses in GCs exposed to heat stress. GCs were transfected with NC or siHO-1 and exposed to heat stress for 2 h. (A–C) Western blot expression of HO-1 and SOD2. (D) SOD activity. (E) MDA content. (F) GSH-Px activity. Data represent mean ± SEM; n = 3 in each group. *P < 0.05; **P < 0.01; ***P < 0.001.