Source: University of California
Summary: New research in animal models suggests that the Type 2 diabetes compromises the collagen within bones, making the bones less flexible and more likely to break.
In healthy bones, networks of collagen fibers stretch and slide in response to strain, which helps the bones resist cracking. Type 2 diabetes impairs cardiovascular and kidney function, and is also known to be a risk factor for bone fractures, but exactly how diabetes makes bones more fragile has been unclear. According to the new study by the researchers from the University of California, hyperglycemia in diabetes leads to the accumulation of so-called advanced glycation end products, which bind collagen fibers to each other and impair their stretching and sliding. The team looked at factors outside of bone density that could explain bone fragility in diabetes. They found that the disease compromises the collagen within bones, making the bones less flexible and more likely to break. The study findings were published in the journal Journal of Bone and Mineral Research.
The researchers examined bones from the lower back and forearm of lean, obese and diabetic obese rat models. They imaged the bones with high-resolution CT scans, tested their biomechanical properties, and measured the collagen networks‘ response to strain using small-angle X-ray scattering. They then simulated the contribution of these various factors to bone strength using supercomputers. By comparing the obese rats with the diabetic obese rats, the research team could isolate the effect of hyperglycemia on bone fragility. The researchers note that they did not study animals with an advanced duration and severity of diabetes, which may limit generalizability, but they expect that long-term diabetes would only further impair bone strength.
Assoc. Prof. Aaron Fields said, “Our findings shed light on why bones in a diabetic milieu are so fragile”, “And in doing so, may lead to better diagnostic tools and therapies for managing fracture risk in adults with diabetes.”
More Information: Claire Acevedo et al, “Contributions of material properties and structure to increased bone fragility for a given bone mass in the UCD-T2DM rat model of type 2 diabetes”, Journal of Bone and Mineral Research (2018). DOI: 10.1002/jbmr.3393