Prescimone Tommaso, Masotti Silvia, D'Amico Andrea, Caruso Raffaele, Cabiati Manuela, Caselli Chiara, Viglione Federica, Verde Alessandro, Del Ry Silvia, Giannessi Daniela
CNR Institute of Clinical Physiology, Laboratory of Cardiovascular Biochemistry, Pisa, Italy.
Scuola Superiore Sant'Anna, Pisa, Italy.
Cardiovasc Pathol. 2014 Sep-Oct;23(5):272-82. doi: 10.1016/j.carpath.2014.04.003. Epub 2014 Apr 13.
Cardiomyocyte apoptosis increases in heart failure (HF) and is implicated in disease progression. The apoptotic cell is not inevitably committed to death, and appropriate therapy like left ventricular assist device (LVAD) support could offer a rescue of cellular functions. Literature data regarding the modulation of the apoptotic process during LVAD support are still controversial.
To assess whether LVAD implantation modifies the apoptotic profile in the heart, cardiac tissue was collected from end-stage HF patients before LVAD implant (pre-LVAD, n=22) and at LVAD removal (post-LVAD, n=6) and from stable HF patients on medical therapy without prior circulatory support (HTx, n=7) at heart transplantation as control. Caspase (Casp)-3, Bax, Bcl-2, and Hsp72 cardiac mRNA and protein expression were evaluated by real-time polymerase chain reaction and Western blotting (WB) in the three groups of patients. Immunohistochemical analysis, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, and DNA laddering analysis were performed; cellular size and interstitial fibrosis content were also determined.
All the apoptotic indices were increased in the post-LVAD group compared to pre-LVAD, specially antiapoptotic Hsp72 and proapoptotic Bax (Hsp72: 3.27±0.41 vs. 0.76±0.14, P<.001; Bax: 2.15±0.38 vs. 1.10 ± 0.29, P=.035; post-LVAD vs. pre-LVAD, respectively). The significant increase in Hsp72 was confirmed by WB and immunohistochemical analysis.
LVAD appears to induce an activation of apoptotic mediators, mainly at the mitochondrial level, while the following activation of Casp-3 is reduced by the significant increase of Hsp72, whose enhancement could be an important factor in cardiac remodeling associated with LVAD support.
心力衰竭（HF）时心肌细胞凋亡增加，并与疾病进展有关。凋亡细胞并非必然走向死亡，而诸如左心室辅助装置（LVAD）支持等适当治疗可挽救细胞功能。关于LVAD支持期间凋亡过程调节的文献数据仍存在争议。
为评估LVAD植入是否改变心脏的凋亡特征，在LVAD植入前（LVAD植入前，n = 22）和LVAD移除时（LVAD植入后，n = 6）从终末期HF患者收集心脏组织，并在心脏移植时从接受药物治疗且无先前循环支持的稳定HF患者（HTx，n = 7）收集心脏组织作为对照。通过实时聚合酶链反应和蛋白质印迹法（WB）评估三组患者中半胱天冬酶（Casp）-3、Bax、Bcl-2和Hsp72的心脏mRNA和蛋白质表达。进行免疫组织化学分析、末端脱氧核苷酸转移酶介导的dUTP缺口末端标记测定和DNA梯状分析；还测定细胞大小和间质纤维化含量。
与LVAD植入前相比，LVAD植入后组所有凋亡指标均升高，特别是抗凋亡的Hsp72和促凋亡的Bax（Hsp72：3.27±0.41对0.76±0.14，P<0.001；Bax：2.15±0.38对1.10±0.29，P = 0.035；分别为LVAD植入后与LVAD植入前）。WB和免疫组织化学分析证实Hsp72显著增加。
LVAD似乎诱导凋亡介质的激活，主要在线粒体水平，而随后Casp-3的激活因Hsp72的显著增加而降低，Hsp72的增强可能是与LVAD支持相关的心脏重塑的重要因素。
