In Vitro and In Vivo Potential of Human Stem Cell-Derived Conditioned Medium (Secretome) and Exosomes as a Novel Treatment for Osteoarthritis: A Systematic Review of Experimental Studies.

BACKGROUND

Osteoarthritis is a disease that occurs due to articular cartilage degeneration. It commonly manifests as fluctuating joint pain, stiffness, and locomotor restriction. In the past decade, researchers have discovered that mesenchymal stem cells (MSCs) could potentially treat osteoarthritis. However, improper administration of MSCs may cause serious adverse events, and the process can be costly. Recent findings suggest that MSC secretomes can reverse the damage caused by osteoarthritis. This study aims to systematically report the in vitro and in vivo potential of the secretome as a novel treatment for osteoarthritis.

METHODS

We searched PubMed, the Cochrane Library, and the Directory of Open Access Journals (DOAJ) for open-access experimental articles in English containing primary data regarding in vivo and in vitro effects of secretome on osteoarthritis, excluding studies utilizing non-physiologic human stem cells. The outcomes assessed included method and timing of assessment, all reported outcomes, and any significant differences found.

RESULTS

Secretome was significantly able to preserve mechanical tensile and compressive strength, increase chondrocyte survival and proliferation, promote autophagy of senescent and damaged cells, reduce fibrosis and joint stiffness, reduce joint inflammation, inhibit pathologic processes following inflammation, and reduce the expression of pain-associated genes in osteoarthritic joints. Experimental studies reported that joints receiving secretome therapy demonstrated histologic and functional recovery to levels comparable to healthy joints.

CONCLUSIONS

Secretome therapy represents a novel treatment modality with the potential to provide a definitive and comprehensive solution for osteoarthritis. Further research regarding the safety and efficacy of secretome therapy in human joints is needed to facilitate its clinical application as soon as possible.