L-carnitine Effectively Induces hTERT Gene Expression of Human Adipose Tissue-derived Mesenchymal Stem Cells Obtained from the Aged Subjects.

Abstract

Human mesenchymal stem cells (hMSCs) are attractive candidates for cell therapy and regenerative medicine due to their multipotency and ready availability, but their application can be complicated by the factors such as age of the donors and senescence-associated growth arrest during culture conditions. The latter most likely reflects the fact that aging of hMSCs is associated with a rise in intracellular reactive oxygen species, loss of telomerase activity, decrease in human telomerase reverse transcriptase (hTERT) expression and finally eroded telomere ends. Over-expression of telomerase in hMSCs leads to telomere elongation and may help to maintain replicative life-span of these cells. The aim of this study was to evaluate of the effect of L-carnitine (LC) as an antioxidant on the telomerase gene expression and telomere length in aged adipose tissue-derived hMSCs.For this purpose, cells were isolated from healthy aged volunteers and their viabilities were assessed by MTT assay. Quantitative gene expression of hTERT and absolute telomere length measurement were also performed by real-time PCR in the absence and presence of different doses of LC (0.1, 0.2 and 0.4 mM).The results indicated that LC could significantly increase the hTERT gene expression and telomere length, especially in dose of 0.2 mM of LC and in 48 h treatment for the aged adipose tissue-derived hMSCs samples.It seems that LC would be a good candidate to improve the lifespan of the aged adipose tissue-derived hMSCs due to over-expression of telomerase and lengthening of the telomeres.