Plasma heat shock protein 27 is increased in renal dysfunction and habitual smoking in a Japanese general population

Heat shock proteins (HSPs) work as "chaperones" to affect protein folding of newly synthesized or denatured proteins. HSP 27 plays an important role in coronary artery disease or renal disease as the result of oxidative stress. Although habitual smoking is well known to induce oxidative stress, there is no epidemiological evidence between plasma HSP 27 and renal dysfunction or smoking habits.

A total of 451 residents (167 men and 284 women, age 65.7 years) underwent a history and physical examination, and determination of blood chemistries, including plasma levels of HSP 27. HSP 27 levels were measured by using enzyme-linked immunosorbent assay kits.

Elevated HSP 27 levels were independently associated with estimated glomerular filtration rate (eGFR) (p<0.001) and smoking habits (p<0.05). HSP 27 levels were significantly decreased stratified by groups of eGFR (p<0.001 for trend) by analysis of co-variance (ANCOVA) adjusted for age, sex, and smoking habits. HSP 27 levels were increased with more smoking of cigarettes. In particular, HSP 27 levels were increased in the heavy smokers (≥20cigarettes/day) by ANCOVA adjusted for age, sex, and eGFR compared with non-smokers and light smokers (p<0.05 for trend).

The present study demonstrated that HSP 27 levels were strongly related to renal dysfunction and habitual smoking in a dose-response manner in a Japanese general population.