Fig 2: Vitamin D inhibited macrophage apoptosis induced by S. aureus associated infection. (A) Apoptosis detection, Caspase-3/7 (green) and PI (red). Magnification, ×200. (B) Result of western blotting for apoptosis-related proteins. “ns” for not significant, *p < 0.05, **p < 0.01, and ***p < 0.001.

Fig 3: PRP resisted the apoptosis induced by Dex in BMSCs. A TUNEL assay evaluated cell apoptosis. B Western blot analysis shows the expression for Bcl-2 and Caspase-3 apoptosis-related protein in BMSCs exposed to Dex and co-treated with PRP. GAPDH served as an endogenous control. (*p < 0.05 vs. Dex group)

Fig 4: Effects of PRCR, UC-MSCs, and PRCR + UC-MSCs on DEX-treated BMSCs and HUVEC apoptosis. (a, b) Representative images of TUNEL-positive cells (apoptotic cells) of DEX-treated BMSCs and HUVEC apoptosis in different coculture conditions. (c) Quantitative analysis of apoptosis rates of BMSCs and HUVECs, respectively. The PRCR and PRCR+UC-MSCs rescued the DEX-induced apoptotic effects (P < 0.05). (d) Western blotting was conducted to evaluate the expression of the apoptosis-related proteins. The PRCR, UC-MSC, and PRCR + UC-MSC groups significantly blocked caspase-3 activation and increased Bcl-2 expression compared to the DEX group (n = 5, #Comparisons between the DEX group and other groups, P < 0.05; ∗Comparisons between the two groups, P < 0.05). PRCR: platelet-rich plasma clot releasate; UC-MSCs: umbilical cord mesenchymal stem cells; DEX: dexamethasone; HBMSCs: human bone marrow mesenchymal stem cells; HUVECs: human umbilical vein endothelial cells; TUNEL: terminal transferase-mediated deoxyuridine triphosphate (dUTP) nick-end labeling; DAPI: 4′, 6-diamidino-2-phenylindole; GADPH: glyceraldehyde-3-phosphate dehydrogenase.

Fig 5: Vitamin D inhibited excessive ROS expression during S. aureus associated infection. (A) ROS generation fluorescence detection, ROS (green). Magnification, 1,000×. (B) Mean grey value of ROS generation. (C) Apoptosis detection, caspase-3/7 (green) and PI (red). Magnification, ×200. (D) Result of western blotting for apoptosis-related proteins. “ns” for not significant, *p < 0.05, **p < 0.01, and ***p < 0.001.