Diabetic Amputation Cause Better Understood

Due to poor blood function and diminished ability to battle infections, limb amputations are a common occurrence in diabetics. Researchers have recently found that a specific blood vessel receptor that results from diabetes might be responsible for these amputations.

Amputations in diabetics occur due to dysfunction in the cells lining blood vessels in the limbs. This dysfunction can lead to “gangrene and cutaneous ulcers with a severely impaired healing potential, which makes amputation of the diabetic foot an all-too-frequent necessity,” say the study authors.

A receptor known as p75NTR was found to be present in the blood vessels of diabetics, but not in those of healthy non-diabetic individuals. p75NTR was shown in the study to limit new blood vessel growth that is essential in cell tissue healing.

Injecting p75NTR into healthy blood vessels produced cell dysfunction. demonstrating the harmful function of p75NTR. To simulate the effects p75NTR has on diabetics, blood flow was restricted (a common occurrence in diabetes) to healthy muscles, which were then injected with p75NTR. This caused diminished healing abilities, much the same as what happens in the limbs of diabetics.

Researchers then tried to solve the problem by inhibiting p75NTR in diabetic mice, then restricting blood flow to the limbs. The suppression of p75NTR allowed the limbs of the diabetic mice to heal properly.

By better understanding the mechanism that leads to diabetic amputations, and by demonstrating a way to combat this harmful function, this research could bring much needed help to diabetics at risk for amputation. As study author Dr. Costanza Emanueli concludes, “our findings demonstrate the importance of understanding the individual factors responsible for such diabetes-induced complications. The data reveal that by suppressing the action of one particular gene, we can improve recovery of tissues following inadequate blood flow, and this opens up new avenues for its use to combat diabetes-induced vascular disease.”

Source: Defeat Diabetes Foundation: Emanueli, Costanza. Coparali, Andrea. et al. Circulation Research. “Neurotrophin p75 Receptor (p75NTR) Promotes Endothelial Cell Apoptosis and Inhibits Angiogenesis.” July 2008. Fryer, Joanne. Circulation Research news release. July 2008.