Stem cell-based therapy has emerged as an attractive method for regenerating and repairing the lost heart organ. On other hand, poor survival and maintenance of the cells transferred into the damaged heart tissue are broadly accepted as serious barriers to enhance the efficacy of the regenerative therapy. For this reason, external factors, such as antioxidants are used as a favorite strategy by the investigators to improve the cell survival and retention properties. Therefore, the present study was conducted to investigate the In -vitro effect of L-carnitine (LC) on the telomere length and human telomerase reverse transcriptase (hTERT) gene expression in the cardiac differentiated bone marrow resident CD117⁺ stem cells through Wnt3/β-catenin and ERK1/2 pathways. To do this, bone marrow resident CD117⁺ stem cells were enriched by the magnetic-activated cell sorting (MACS) method, and were differentiated to the cardiac cells in the absence (-LC) and presence of the LC (+LC). Also, characterization of the enriched c-kit⁺ cells was performed using the flow cytometry and immunocytochemistry. At the end of the treatment period, the cells were subjected to the real-time PCR technique along with western blotting assay for measurement of the telomere length and assessment of mRNA and protein, respectively. The results showed that 0.2 mM LC caused the elongation of the telomere length and increased the hTERT gene expression in the cardiac differentiated CD117⁺ stem cells. In addition, a significant increase was observed in the mRNA and protein expression of Wnt3, β-catenin and ERK1/2 as key components of these pathways. It can be concluded that the LC can increase the telomere length as an effective factor in increasing the cell survival and maintenance of the cardiac differentiated bone marrow resident CD117⁺ stem cells via Wnt3/β-catenin and ERK1/2 signaling pathway components.

基于干细胞的疗法已成为再生和修复失去的心脏器官的一种有吸引力的方法。另一方面，转移到受损心脏组织中的细胞存活和维持不佳被广泛认为是提高再生治疗功效的严重障碍。出于这个原因，外部因素，如抗氧化剂，被研究人员用作提高细胞存活和保留特性的首选策略。因此，本研究以调查在-vitro对端粒长度和人端粒酶逆转录酶（L-肉碱（LC）的效果的hTERT在心脏分化的骨髓驻地CD117）的基因表达⁺干细胞通过 Wnt3/β-catenin 和 ERK1/2 通路。为此，骨髓驻留 CD117 ⁺干细胞通过磁激活细胞分选 (MACS) 方法富集，并在不存在 (-LC) 和存在 LC (+LC) 的情况下分化为心脏细胞。此外，使用流式细胞术和免疫细胞化学对富集的 c-kit ⁺细胞进行了表征。在治疗期结束时，对细胞进行实时 PCR 技术和蛋白质印迹分析，分别测量端粒长度和评估 mRNA 和蛋白质。结果表明，0.2 mM LC引起端粒长度延长并增加心脏分化CD117中hTERT基因的表达⁺干细胞。此外，观察到 Wnt3、β-连环蛋白和 ERK1/2 作为这些途径的关键组成部分的 mRNA 和蛋白质表达显着增加。可以得出结论，LC 可以通过 Wnt3/β-catenin 和 ERK1/2 信号通路组分增加端粒长度，作为增加心脏分化骨髓驻留 CD117 ⁺干细胞的细胞存活和维持的有效因素。