Platelet-Derived Microparticles Increase Expression of hTERT in Umbilical Cord Mesenchymal Stem Cells

Abstract

Introduction: Mesenchymal stem cells (MSCs) are widely studied due to their self- renewal potential and capacity to differentiate into multiple tissues. However, they have a limited life span of several divisions in vitro, which alters various cellular characteristics and reduces their application. Aim: We evaluated the effect of platelet-derived microparticles on gene expression of hTERT, one of the main factors involved in aging and cell longevity. Materials and methods: Umbilical cord MSCs were used for this study. Cells were characterized by evaluating morphology via inverted microscope and identifying associated surface markers using flow cytometry. Platelet-derived microparticles were prepared by centrifuging platelet bags at varying speeds, and their concen- trations were determined by Bradford assay. At 30% confluency, MSCs were treated with 50 μg/mL of microparticles for five days. Then, RNA was extracted and cDNA was synthesized. Quantitative expression of hTERT was assessed using real-time polymerase chain reaction (PCR). Results: Fibroblast-like cells were isolated from umbilical cord tissue and MSCs were identified by the presence of mesenchymal surface markers via flow cytometry. Real- time PCR showed that gene expression of hTERT increased by more than three times when treated with platelet-derived microparticles, in comparison to expression of the control group. Conclusion: We concluded that platelet-derived microparticles may be a potentially safe and effective method to increase hTERT gene expression in MSCs, ultimately prolonging their life span in vitro.

Platelet Microparticles Accelerate Proliferation and Growth of Mesenchymal Stem Cells through Longevity-Related Genes

“…10,26 However, evidence suggests that sheer shortening of telomere length does not call for aging of MSCs. 5,28 Two main tumor suppressor pathways, namely p16INK4A/pRb and p53/ p21WAF1, are also known as permanent factors implicated in MSC senescence. Some senescent states are primarily determined by high expression of p16 while others are specified by p53, which is needed for coupling of arrested cell cycle progression to other cellular responses in order to face with various physiological requirements and to meet the deserved responses to different forms of stress.…”

Characterization and Therapeutic Use of Extracellular Vesicles Derived from Platelets

“…They demonstrated the potential effect of PRP-EXOs on the proliferation and migration of MSCs. In addition to bone marrow MSCs, PL-EVs increased the gene expression of human telomerase reverse transcriptase (hTERT) in umbilical cord-derived MSCs in vitro [ 150 ]. These results suggest that PL-EVs could potentially prolong the lifespan of MSCs, but this statement needs to be definitively verified in vivo.…”