Studies concerning correlations between pituitary adenomas and cell apoptosis have mainly focused on upstream apoptosis signaling, but seldom on downstream mediators. In the present study, second mitochondria-derived ...Studies concerning correlations between pituitary adenomas and cell apoptosis have mainly focused on upstream apoptosis signaling, but seldom on downstream mediators. In the present study, second mitochondria-derived activator of caspases (Smac), X-linked inhibitor of apoptosis protein (XIAP), and caspase-3 protein were qualitatively analyzed using immunohistochemistry, and quantified by western blot. Smac, XIAP, and caspase-3 mRNA expressions were detected by reverse transcription-PCR. Results showed that XIAP protein and mRNA expressions were greater in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. However, Smac and caspase-3 protein and mRNA expressions were lower in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. In the invasive pituitary adenomas, Smac expression was positively correlated with caspase-3 protein and mRNA expression (Protein: r = 0.55, P 0.01; mRNA: r = 0.50, P 0.01). Smac and caspase-3 expressions were negatively correlated with XIAP protein and mRNA expression (Protein: r = -0.56, -0.64, P 0.01; mRNA: r = -0.69, -0.67, P 0.01). However, no significant differences in correlation among Smac, XIAP, and caspase-3 were detectable in noninvasive pituitary adenomas. These data indicated that high expression of XIAP and low expression of Smac and caspase-3 suppressed cell apoptosis and led to enhanced invasiveness of pituitary adenomas. Thus, Smac, XIAP, and caspase-3 may be useful markers in determining the invasive behavior of pituitary adenomas.展开更多
文摘Studies concerning correlations between pituitary adenomas and cell apoptosis have mainly focused on upstream apoptosis signaling, but seldom on downstream mediators. In the present study, second mitochondria-derived activator of caspases (Smac), X-linked inhibitor of apoptosis protein (XIAP), and caspase-3 protein were qualitatively analyzed using immunohistochemistry, and quantified by western blot. Smac, XIAP, and caspase-3 mRNA expressions were detected by reverse transcription-PCR. Results showed that XIAP protein and mRNA expressions were greater in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. However, Smac and caspase-3 protein and mRNA expressions were lower in the invasive pituitary adenoma group compared with the noninvasive pituitary adenoma group. In the invasive pituitary adenomas, Smac expression was positively correlated with caspase-3 protein and mRNA expression (Protein: r = 0.55, P 0.01; mRNA: r = 0.50, P 0.01). Smac and caspase-3 expressions were negatively correlated with XIAP protein and mRNA expression (Protein: r = -0.56, -0.64, P 0.01; mRNA: r = -0.69, -0.67, P 0.01). However, no significant differences in correlation among Smac, XIAP, and caspase-3 were detectable in noninvasive pituitary adenomas. These data indicated that high expression of XIAP and low expression of Smac and caspase-3 suppressed cell apoptosis and led to enhanced invasiveness of pituitary adenomas. Thus, Smac, XIAP, and caspase-3 may be useful markers in determining the invasive behavior of pituitary adenomas.
文摘目的探讨黄酮类化合物芹菜素对大鼠实验性心肌缺血/再灌注(ischemia/reperfusion,I/R)时心肌细胞凋亡与Bcl-2、Bax、Caspase-3蛋白表达的影响,并分析心肌组织病理学损伤程度。方法采用结扎左冠状动脉前降支,心肌缺血45 min,再灌注2 h制作缺血/再灌注模型。将大鼠随机分为8组,即正常组(normal group,Normal)、假手术组(sham oper-ation group,Sham)、生理盐水缺血/再灌注组(saline ischemi-a-reperfusion group,NS)、溶剂对照组(solvent control group,Sol)、美托洛尔对照组(metoprolol control group,Meto)、芹菜素低、中、高剂量(1、2、4 mg.kg-1)用药组(apigenin low,medium and high dose treatment group,Api1,Api2,Api4)。再灌注2 h后迅速取出心脏,TUNEL法原位标记凋亡的心肌细胞;免疫组化法测Bcl-2、Bax和Caspase-3蛋白表达;做病理组织切片检查心肌损伤情况。结果芹菜素各剂量组心肌细胞凋亡率明显低于NS组(P<0.05),Api1,Api2,Api4能剂量依赖性地降低大鼠缺血/再灌注心肌细胞凋亡率;芹菜素各剂量组剂量依赖性地提高大鼠心肌缺血/再灌注的Bcl-2蛋白表达量(P<0.05)、降低大鼠心肌缺血/再灌注的Bax、Caspase-3蛋白表达量(P<0.05);芹菜素各剂量组与NS组比较,心肌组织损伤的病理学变化明显减轻(P<0.05)。结论芹菜素对缺血/再灌注心肌的保护效应可能与其抑制缺血/再灌注心肌细胞凋亡有关;芹菜素抗心肌凋亡作用的机制可能与其上调Bcl-2蛋白表达和下调Bax、Caspase-3蛋白表达有关;芹菜素能明显减轻心肌组织损伤。