Research finds link between diabetes and bone health
Diabetes can cause serious health complications, including heart disease, blindness, kidney failure and lower-extremity amputations. A lesser-known but equally grave complication is the effect of diabetes on bone health.
“Clinical trials have revealed a startling elevation in fracture risk in diabetic patients,” said Liyun Wang, associate professor of mechanical engineering at the University of Delaware, USA. “Bone fractures can be life threatening – nearly one in six hip fracture patients dies within a year of injury.”
Because physical exercise is proven to improve bone properties and reduce fracture risk in non-diabetic people, Wang and her research group decided to test its efficacy in Type 1 diabetes. The findings of their study are reported in the journal Bone.
Wang explained that osteocytes are critical to maintenance of the tissue quality and mechanical integrity of bone. As the primary “mechanosensing” cells, osteocytes orchestrate bone’s adaptation processes under mechanical cues such as exercise.
“We suspected that the response of diabetic bone to mechanical loading would be compromised due to impaired mechanosensing of osteocytes under hyperglycaemic, or high blood sugar, conditions,” she said.
The study demonstrated that exercise-induced bone formation was maintained in mildly diabetic mice at a similar level as non-diabetic controls, while the positive effects of exercise were nearly abolished in severely diabetic mice. At the cellular level, the researchers found that hyperglycaemia reduced the sensitivity of osteocytes to mechanical stimulation and suppressed osteocytes’ secretion of proteins and signalling molecules that help build stronger bone.
“Our work demonstrates that diabetic bone can respond to exercise when the hyperglycaemia is not severe, which suggests that mechanical interventions may be useful to improve bone health and reduce fracture risk in mildly affected diabetic patients,” said Wang. “Coming at it from the other side, our results stress the importance of maintaining good control of blood sugar in diabetic patients so that exercise can do its work in maintaining bone health.”
Source: University of Delaware
Parajuli A, Liu C, Li W, et al. Bone’s responses to mechanical loading are impaired in type 1 diabetes. Bone. 2015 Jul 13;81:152-160. doi: 10.1016/j.bone.2015.07.012.