(A) SND treatment exerts anti-oxidant effects in H295R cells. Adrenocortical H295R cells were subjected to pre-treatment with or without SND for 24 h, followed by incubation with H2O2 for 30 min. In all groups, culture media was replaced at 24 h following treatment and COX-2 mRNA expression was measured. (B) SND treatment antagonizes H2O2-induced generation of ROS in adrenocortical H295R cells. H295R cells were subjected to pre-treatment with or without SND for 24 h, followed by H2O2 treatment for 15 min. ROS generation evaluated by quantification of DFCH-DA staining under a fluorescence microscope (magnification, ×40). (C) SND protects against H2O2-induced loss of mitochondrial membrane potential in adrenocortical H295R cells. Cultured H295R cells were treated as in B and mitochondrial membrane integrity was quantified using JC-1 staining and evaluation under a fluorescence microscope (magnification, ×40). Values are expressed as the mean ± standard error of the mean (n=6/group). ##P<0.01 and ###P<0.001 vs. blank or SND+H2O2 group; **P<0.01 vs. H2O2 group. COX-2, cyclooxygenase 2; SND, Sini decoction; ROS, reactive oxygen species; DFCH-DA, 2′-7′-dichlorodihydrofluorescein diacetate.