Role of Inflammation in the Pathogenesis of Diabetic Peripheral Neuropathy

BACKGROUND: Diabetic peripheral neuropathy (DPN) means the presence of symptoms and/or signs of peripheral nerve damage that occur to people with diabetes, excluding all other causes of neuropathy. Chronic hyperglycaemia leads to increased secretion of tumour necrotic factor-alpha (TNF-α), with the development of micro and macroangiopathy, damage to nerve fibres and local demyelination. AIM: To determine the role of inflammation in the peripheral nerve damage process concerning people suffering from type II diabetes mellitus. MATERIAL AND METHODS: The study included a total of 80 subjects, men and women, divided into two groups: an examined group (n = 50) consisting of subjects with DPN at the age from 30 to 80 years and a control group (n = 30) of healthy subjects aged from 18 to 45. In the investigated group, a neurological examination was performed using the Diabetic Neuropathy Symptoms (DNS) Score and Electroneurography. All the subjects had the blood plasma concentration of TNF-α by ELISA technique. RESULTS: The average value of TNF-α in the test group was 8.24 ± 2.899 pg/ml, while the control group was 4.36 ± 2.622 pg/ml (p < 0.0001). The average value of TNF-α was correlated with the achieved DNS score in the investigated group (p = 0.005). Concerning the linear association of the concentration of TNF-α with the peripheral nerve velocity in the investigated group, no statistical significance was detected. CONCLUSION: Inflammation can play a role in the pathogenesis of diabetic autonomic neuropathy and cranial neuritis.