No abstract

We aimed to assess the effects of ACE2/GHRL on the proliferation and apoptosis of synovial cells in osteoarthritis (OA). 20 healthy mice were randomly assigned into blank group and experimental group (ACE2 was knocked down). In addition, 30 mice were subdivided into 3 group (n = 10) and treated with saline solution, GHRL (auxin), and GHRL+CHPAA (Auxin inhibitor) followed by analysis of synovial cell proliferation, apoptosis and inflammatory factor level by Western blot analysis, MTT and flow cytometry. Experimental group exhibited decreased cell proliferation, increased apoptosis upon silencing of ACE2 (p < 0.05) along with elevated expressions of Caspase3 and Bax protein and decreased Bcl-2, inflammatory factors and the GHRL level (p < 0.05). Treatment with GHRL increased cell proliferation cells and decreased apoptosis. Meanwhile, Bcl-2 expression and IL-1β, IL-6 and IL-8 levels in GHRL group were significantly lower than other two groups whilst Caspase-3 and Bax level was significantly higher (p < 0.05). After CHPAA treatment, ACE2 expression in CHPAA group was dramatically declined (p < 0.01). In conclusion, ACE2/GHRL might alleviate OA progression through regulation of cell proliferation, apoptosis and inflammation of synoviocytes, providing insight into a therapeutic target for treating OA.