Stress Response Profiles in Human Fibroblasts Exposed to Heat Shock or Oxidative Stress

The upregulation of stress proteins is an important step in the cellular defense against various endogenous and exogenous stressors, and the stress response systems are therefore essential to cell maintenance and survival. In order to evaluate the cellular capability to cope with exogenous stressors, we investigated stress response profiles in cultured human fibroblasts exposed to short-term heat shock or oxidative stress. Quantitative PCR analysis as well as Western blotting demonstrated a specific upregulation of Hsp70 mRNA and protein after heat shock, while heme oxygenase 1 (HO1 or Hsp32) mRNA and protein was specifically upregulated following H₂ O₂ -induced oxidative stress. Hsp70 and HO1 should therefore be considered as useful biomarkers for acute heat stress and oxidative stress, respectively. Moreover, the results indicate that the expression of Hsp70 and HO1 in response to exogenous stressors may be regulated through different mechanisms.