A research team led by a Michigan State University professor has discovered a link between diabetes and bone marrow nerve damage that may help treat one of the disease's most common and potentially blindness-causing complications.
The key to better treating retinopathy - damage to blood vessels in the retina that affects up to 80 percent of diabetic patients - lies not in the retina but in damage to the nerves found in bone marrow that leads to the abnormal release of stem cells, said Julia Busik, an associate professor in MSU's Department of Physiology.
"With retinopathy, blood vessels grow abnormally in the retina, distort vision and eventually can cause blindness," said Busik, whose research appears in a recent issue of the Journal of Experimental Medicine. "There has been a lot of progress in treating the complication, but most treatments use a laser that is painful to the patient and destroys parts of the retina."
Busik and her team found that nerve damage in diabetic bone marrow - where stem cells known as endothelial progenitor cells reside - affects the daily release of those EPCs into the bloodstream. Normally EPCs would exit the bone marrow and repair damage done in the vascular system during sleep.
Using animal models, the research team observed that the pattern of EPC release is faulty in diabetic bone marrow, creating abnormally low levels of EPCs during sleep, when they are needed most. That decrease in EPC release from a diabetic patient's bone marrow preceded the development of retinopathy.
"When the bone marrow suffers nerve damage in diabetic patients, it no longer provides a signal for the timely release of these reparative stem cells," Busik said.