Diabetic nephropathy, in itself a debilitating condition, is also a milepost on the road to endstage renal disease and kidney failure. It represents the beginning of the process of the deterioration of the kidneys that occurs as a result of the blood imbalances inherent in diabetes, and is associated with constant or intermittent hyperglycemia. The higher glucose levels go, and the longer they stay high, the more strain is put on the blood vessels of the kidneys, as well as on those of the eye, heart, limbs, and the entire circulatory system. This is the reason that hyperglycemia causes not only nephropathy, but also diabetic retinopathy, neuropathy, lower-extremity arterial disease, and eventually heart disease and kidney failure. Now, a study on rats suggests that a selenium supplement reduces the overall plasma glucose level and also greatly reduces the effect of hyperglycemia in the kidneys.
More testing remains to confirm that it offers the same benefits to humans with diabetes.
Christelle Douillet other researchers who conducted the study report that selenium has an antioxidant effect that helps to a certain extent in preventing kidney disease. But it also appears to have an insulin-like effect in lowering blood glucose. Antioxidants alone generally help to delay diabetic complications, but since renal complications are caused by microaneurysms in small vessels that appear to be caused partly by high glucose, the insulin-like effect of selenium adds an extra protection, the researchers state.