To investigate the effect of Myocardin-related transcription factor A (MRTF-A) on apoptosis induced by ischemic/reperfusion (I/R), middle cerebral artery occlusion/reperfusion (MCAO/R) in rats were applied to mimic I/R. The neurological deficit score, cerebral infarct size, cortical neuron apoptosis and cleaved caspase 3 level were evaluated to determine the effect and the level of apoptosis by TTC straining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) straining, Western blot and immunofluorescence staining. The myeloid cell leukemia-1 (Mcl-1) expression, release of cytochrome C (Cyt C) and its colocalization with apoptotic protease activating factor-1 (Apaf-1) were analyzed by quantitative real-time PCR (qRT-PCR), Western blot, and immunofluorescence staining. The results showed that MRTF-A overexpression could decrease the neurological deficit score and reduce cerebral infarct size ([Formula: see text] versus Sham). In the MRTF-A-I/R group, TUNEL-positive cells and apoptosis ratio (%) ([Formula: see text]%) were significantly decreased compared to the Neg-I/R group ([Formula: see text]%) at 24[Formula: see text]h reperfusion. Meanwhile, the cleaved caspase 3 expression revealed a similar trend while the expression of Mcl-1 was the opposite. Moreover, MRTF-A overexpression significantly enhanced Mcl-1 fluorescence intensity, which up-regulated the mRNA and protein level ([Formula: see text] or [Formula: see text] versus Neg-I/R). Furthermore, MRTF-A overexpression markedly inhibited the release of Cyt C, and decreased the colocalization with Apaf-1 in the cytoplasm ([Formula: see text] or [Formula: see text] versus Neg-I/R). All the data indicated that MRTF-A overexpression could improve the neurological function against cerebral I/R-induced apoptosis since underlying mechanism might be involved in the Mcl-1/Cyt C/cleaved caspase 3 signaling pathway.

中文翻译：

---

心肌素相关转录因子 A 的过表达通过 Mcl-1/Cyt C/cleaved caspase 3 通路减弱大脑中动脉闭塞/再灌注诱导的细胞凋亡

为了研究心肌素相关转录因子A（MRTF-A）对缺血/再灌注（I/R）诱导的细胞凋亡的影响，应用大鼠大脑中动脉闭塞/再灌注（MCAO/R）模拟I/R。通过 TTC 过滤、末端脱氧核苷酸转移酶 dUTP 缺口末端标记 (TUNEL) 过滤、蛋白质印迹和免疫荧光染色，评估神经功能缺损评分、脑梗死面积、皮质神经元凋亡和切割的 caspase 3 水平以确定细胞凋亡的效果和水平。通过定量实时PCR（qRT-PCR）分析髓细胞白血病-1（Mcl-1）的表达，细胞色素C（Cyt C）的释放及其与凋亡蛋白酶激活因子-1（Apaf-1）的共定位， Western印迹和免疫荧光染色。结果表明，MRTF-A 过表达可以降低神经功能缺损评分并减少脑梗死面积（[公式：见正文] vs Sham）。MRTF-AI/R组TUNEL阳性细胞和凋亡率（%）（[公式：见文]%）较Neg-I/R组（[公式：见文]%）显着降低。 24【公式：见正文】h再灌注。同时，裂解的 caspase 3 表达显示出相似的趋势，而 Mcl-1 的表达则相反。此外，MRTF-A 过表达显着增强了 Mcl-1 荧光强度，从而上调了 mRNA 和蛋白质水平（[公式：参见文本] 或 [公式：参见文本] 与 Neg-I/R）。此外，MRTF-A 过表达显着抑制 Cyt C 的释放，并降低了与 Apaf-1 在细胞质中的共定位（[公式：见正文]或 [公式：见文本] 与 Neg-I/R)。所有数据表明，MRTF-A 过表达可以改善神经功能对抗脑 I/R 诱导的细胞凋亡，因为潜在机制可能涉及 Mcl-1/Cyt C/cleaved caspase 3 信号通路。