April - June 2021, Volume 17, Issue 2

Qu P, Li Y, Hu X, Guo Y, Zhu Y, Li X , Zhao J

The Effect of Adiponectin Via Regulating the Bone Microenvironment Oxidative Stress on Osteogenesis in Type 2 Diabetic Rats

Acta Endo (Buc) 2021, 17 (2): 168-176
doi: 10.4183/aeb.2021.168

Objective. To observe the effect of adiponectin on osteogenesis in type 2 diabetic rats. Methods. The 4th-week-old male SD rats were divided into normal control group (n=18) and diabetic model group (n = 42). Type 2 diabetes was induced by high-fat and high-sugar diet and intraperitoneal injection of a low dose of streptozotocin (STZ). The successfully-induced diabetic rats were divided into diabetic group (DM=18) and adiponectin intervention group (APN=18). APN group was injected with APN 10 μg/kg*d. The rats were separately sacrificed at the 4th, 8th and 12th week after the intervention. Bone microstructure and adipose tissue were observed via HE staining. Bone marrow was extracted from one side of the femur, and the supernatant was achieved by centrifugation. After BMD assessed by DXA, the other side of the femur was for further HE staining. Runx-2 expression in the bone marrow cells was detected by RT-PCR. BALP and AOPPs in bone marrow supernatant were assayed by ELISA. AGEs were detected by immunohistochemical staining. Results. With the feeding time over, blood glucose, AOPP, and AGEs were increased, and Runx-2 mRNA, BALP, BMD were decreased in diabetic rat group(P<0.05). Oxidative stress (OS) maker (AOPP) was decreased and osteogenesis makers (Runx2 mRNA, BALP) were increased after intervention with exogenous adiponectin (P<0.05). At the 8th and 12th week, the trabecular bone became thinner and broken, and the fat cell number increased in all 3 groups, especially in the DM group. The adiponectin intervention group showed that the trabecular bone structure was moderately restored. Conclusions. OS is obvious in bone microenvironment in diabetic rats. OS may have an inhibitory effect on regulation of osteogenic differentiation factor Runx2, causing down regulation of osteoblast differentiation and bone formation. Adiponectin may improve OS response and protect the bone structure.

Keywords: type 2 diabetes, osteoporosis, oxidative stress, adiponectin, osteogenesis.

Correspondence: Yikun Zhu, Shanxi Medical University, Second Hospital, Department of Endocrinology, 382 Wuyi Road, Taiyuan, Shanxi, 030001, PR China, E-mail: zyk1003@126.com