Effect of miR-21 in mesenchymal stem cells-derived extracellular vesicles behavior

BACKGROUND

A challenging new branch of research related to aging-associated diseases is the identification of miRNAs capable of modulating the senescence-associated secretory phenotype (SASP) which characterizes senescent cells and contributes to driving inflammation.

METHODS

Mesenchymal stem cells (MSC) from human umbilical cord stroma were stable modified using lentivirus transduction to inhibit miR-21-5p and shotgun proteomic analysis was performed in the MSC-derived extracellular vesicles (EV) to check the effect of miR-21 inhibition in their protein cargo. Besides, we studied the paracrine effect of those modified extracellular vesicles and also their effect on SASP.

RESULTS

Syndecan-1 (SDC1) was the most decreased protein in MSC-miR21--derived EV, and it was involved in inflammation and EV production. MSC-miR21--derived EV were found to produce a statistically significant inhibitory effect on SASP and inflammaging markers expression in receptor cells, and in the opposite way, these receptor cells increased their SASP and inflammaging expression statistically significantly when treated with MSC-miR-21+-derived EV.

CONCLUSION

This work demonstrates the importance of miR-21 in inflammaging and its role in SASP through SDC1.

Therapy free of cells vs human mesenchymal stem cells from umbilical cord stroma to treat the inflammation in OA

Osteoarthritis (OA) is closely linked to the increase in the number of senescent cells in joint tissues, and the senescence-associated secretory phenotype (SASP) is implicated in cartilage degradation. In the last decade, extracellular vesicles (EV) in combination with the use of miRNAs to modify post-transcriptional expressions of multiple genes have shown their utility in new therapies to treat inflammatory diseases. This work delves into the anti-inflammatory effect of extracellular vesicles derived from mesenchymal stem cells (MSC) previously modified to inhibit the expression of miR-21. We compare the efficacy of two treatments, MSC with their miR-21 inhibited through lentiviral transfection and their EV, against inflammation in a new OA animal model. The modified MSC and their EV were intraperitoneally injected in an OA animal model twice. One month after treatment, we checked which therapy was the most effective to reduce inflammation compared with animals untreated. Treated OA model sera were analyzed for cytokines and chemokines. Subsequently, different organs were analyzed to validate the results obtained. EV were the most effective treatment to reduce chemokines and cytokines in serum of OA animals as well as SASP, in their organs checked by proteomic and genomic techniques, compared with MSC alone in a statistically significant way. In conclusion, MSC-miR-21⁻-derived EV showed a higher therapeutic potential in comparison with MSCs-miR-21-. They ameliorate the systemic inflammation through inactivation of ERK1/2 pathway in OA in vivo model.

Action Mechanisms of Small Extracellular Vesicles in Inflammaging

The accumulation process of proinflammatory components in the body due to aging influences intercellular communication and is known as inflammaging. This biological mechanism relates the development of inflammation to the aging process. Recently, it has been reported that small extracellular vesicles (sEVs) are mediators in the transmission of paracrine senescence involved in inflammatory aging. For this reason, their components, as well as mechanisms of action of sEVs, are relevant to develop a new therapy called senodrugs (senolytics and senomorphic) that regulates the intercellular communication of inflammaging. In this review, we include the most recent and relevant studies on the role of sEVs in the inflammatory aging process and in age-related diseases such as cancer and type 2 diabetes.