In Diabetes, A Material Witness
A handheld tool that measures the properties making up bone has enabled researchers to validate a trend long associated with many diabetics—an increased risk of fractures. The test, conducted by the Mayo Clinic and published online last month in the Journal of Bone and Mineral Research1 could eventually have broad implications for the screening, monitoring and treatment of a disease that now affects about 347 million people worldwide. It bolsters the argument that bone strength should be added to the list of complications associated with diabetes.
The data collected from this study represents yet another example of how researchers are gaining new insights into diabetes. Eureka’s four-part series earlier this year looked specifically at the interplay between the regulation of glucose and fat metabolism, and the skeletal system.2
The Mayo study, which was conducted in 60 postmenopausal women ages 50-80, is significant in that it allows researchers to go beyond the traditional dual energy X-ray absorptiometry or DEXA scans now used to determine bone density in the aging, and actually assess the material properties that make up the bone.
The small study included 30 women who had been diagnosed with Type 2 diabetes (T2D) at least a decade ago and 30 nondiabetic matched controls. Using a device designed to measure the ability of bone tissue to prevent small cracks growing into full-blown fractures, researchers inserted a microscopic needle into the shinbones of study participants, causing a tiny fracture. Essentially, the deeper the probe, the more fragile the bone.
Sundeep Khosla, an expert in the pathophysiology of bone loss in women and men who led the study, said the T2D patients had significantly lower bone material strength compared to the controls, though the differences were not as striking when researchers adjusted for age, hypertension, nephropathy, neuropathy, retinopathy, and vascular disease.
Khosla said the study also found that the women with T2D had significantly reduced serum markers of bone turnover compared to the controls. The results of the study correlate with what was previously observed in diabetic animal models, says Khosla.
What leads to bone deterioration in diabetics is still not well understood, however. One theory is that the chronic hyperglycemia that persists in diabetics emits sugar molecules as end products that get stuck on different tissues, including bone collagen. When this happens, it can weaken the structure of the collagen, potentially altering the bone environment, says Khosla.
Rana Samadfam, a principal scientist at Charles River Laboratories who was not involved in the study, said the cross-talk between bone and organs involved in energy metabolism may also play a role in weakening the diabetic bones.
Samadfam, who plays a key role in designing studies and interpreting data relevant to bone, diabetes and endocrine system, said the test used in the Mayo study is an interesting one. “However, the reproducibility of this test in different labs requires more validation,” she said. “Also, because the test is performed by inserting a needlelike device in the bone, some patients may not be willing to participate.”
Going forward, Khosla said his team wants to study bone material strength in a much larger cohort of patients. He said he also would like to look at diabetics with fractures and compare them to those without fractures to see if there are any differences in bone strength between the two groups.
- Journal of Bone and Mineral Research DOI: 10.1002/jbmr.2106 2013
- Eureka, https://eureka.criver.com/diabetic-bones/ https://eureka.criver.com/diabetes-and-the-skeleton-a-sweeter-look-to-the-future/ https://eureka.criver.com/type-2-diabetes-treatments-effects-on-bone/; https://eureka.criver.com/anti-diabetes-therapies-and-bone-safety/