Effects of young extracellular matrix on the biological characteristics of aged tendon stem cells

Age-related changes in the properties of tendon stem cells (TSCs) may play a role in the progressive degeneration and increased risk of injury to tendon tissue. Recent reports have demonstrated that a decellularized extracellular matrix (DECM) can provide an appropriate niche to maintain the proliferation and differentiation capacity of adult stem cells.We investigated the biological effects of DECM obtained from young TSCs on the proliferation, stemness, senescence, and differentiation of the aged TSCs.Tendon stem cells were isolated from rat patellar tendons and the DECM was collected. The proliferative capacity, β-galactosidase activity, stem cell marker expression, and tenogenic differentiation potential of TSCs were assessed.Our results showed that DECM from young TSCs enhanced the proliferation and tenogenic differentiation of aged TSCs. Moreover, the senescence-associated β-galactosidase activity of aged TSCs was decreased by young DECM. After being cultured on the young DECM, the expression of stem cell markers by aged TSCs was more extensive. The young DECM preserved stem cell properties of aged TSCs.Taken together, the impaired capacity of aged TSCs can be rejuvenated by exposure to young DECM. The positive results in our study suggest that young TSC-derived DECM may provide a novel approach for the prevention and treatment of age-dependent tendon disorders.