Heat shock protein 27 is associated with better nerve function and fewer signs of neuropathy

Abstract

High levels of serum heat shock protein 27 (sHSP27) have been associated with distal symmetric polyneuropathy in patients with type 1 diabetes. Our objective was to investigate the association between sHSP27, neuropathic signs and nerve function in individuals with normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and type 2 diabetes. Participants were recruited consecutively from the population-based Västerbotten Intervention Program (NGT, n = 39, IGT, n = 29, and type 2 diabetes, n = 51) and were matched for age and sex. sHSP27 levels were measured and nerve conduction studies were performed (peroneal and sural nerves). z Scores for each nerve conduction measure were calculated and compiled into a composite z score for the leg. Neuropathy disability score (NDS) was used to assess neuropathic signs. Patients with diabetes had significantly lower sHSP27 levels (geometric mean sHSP27 206 pg/ml, 95% CI 142, 299) than those with IGT (geometric mean sHSP27 455 pg/ml, 95% CI 319, 650, p < 0.05) and controls (geometric mean sHSP27 361 pg/ml, 95% CI 282, 461, p < 0.05). Participants with few signs of neuropathy (first tertile, NDS ≤2) had significantly higher sHSP27 levels (geometric mean sHSP27 401 pg/ml, 95% CI 310, 520) than participants with many signs (third tertile, NDS ≥7) (geometric mean sHSP27 192 pg/ml, 95% CI 128, 288, p = 0.007). The highest sHSP27 tertile was associated with better nerve function, adjusted for age, sex, statin medication and HbA(1c) (OR 2.51, 95% CI 1.25, 5.05, p < 0.05). High sHSP27 levels were associated with better nerve function and fewer neuropathic signs in NGT, IGT and type 2 diabetes.