Abstract:

Objective   To explore the proliferation, anti-apoptosis characteristics and osteogenic differentiation of BMSCs isolated from diabetic rats. Methods   Forty 6-week female adult Sprague-Dawley rats were randomly divided into the control group and experimental group, with 20 animals in each group. The rats in the experimental group were administrated with a single intraperitoneal injection of streptozotocin (STZ, 65mg/kg, dissolved in 5mmol/L citrate buffer, pH 4.5) to induce diabetes mellitus. The control group was treated with the same dose of normal saline. After 10-week treatment, BMSCs were isolated from the two groups by using adherent method. The proliferation of secondpassage BMSCs was evaluated by CCK-8 assay. The apoptosis induced by serum deprivation and 0.3% hydrogen peroxide was assessed by flow cytometry. After 4-week osteoinductive culture, the expressions of COL-I, OCN, and Runx-2 mRNA were detected by RT-PCR. Alkaline phosphatase (ALP) activity was determined in cell lysates using enzyme-linked immunosorbent assay (ELISA). Meanwhile, the capacities of mineralization of BMSCs were measured by VonKossa and alizarin red staining. Results   Diabetic rat models were successfully induced by intraperitoneal injection of STZ. The proliferative and antiapoptotic abilities of BMSCs derived from diabetic rats were significantly decreased compared with those from normal rats (P<0.01). The mRNA expressions of COL-I, OCN and Runx-2 were down-regulated in experimental group. ALP activity in the experimental group was lower than that in the control group. In addition, the ability of osteogenic differentiation decreased significantly. Conclusion   BMSCs derived from diabetic rats show an impaired ability of proliferative, anti-apoptosis and osteogenic differentiation in vitro.

Key words: Diabetes; Osteoporosis; Bone mesenchymal stem cells; Bone formation; Apoptosis