Relationship Between Heat Shock Protein Expression and Obesity With and Without Metabolic Syndrome

Abstract

<b><i>Background:</i></b> Obesity is considered a chronic inflammatory disease in which the physiological mechanism responsible for reducing inflammation is weakened, prompting low-grade inflammation throughout the body. One of the key stress response systems that is dysregulated in obesity is the heat shock response, which is a critical defense mechanism that is activated in stressful conditions. Obesity is primary to metabolic syndrome (MetS) as it appears to lead to the increase in other MetS risk factors. <b><i>Aim of the Study:</i></b> We aimed to investigate the different expression levels of intracellular heat shock protein (<i>iHSP</i>) 70 and <i>iHSP27</i> in obese patients with and without MetS and compare these levels to those of a lean control group. <b><i>Patients and Methods:</i></b> One hundred ten lean subjects were compared with 44 obese subjects without MetS and 56 obese subjects with MetS. <i>HSP70</i> and <i>HSP27</i> mRNA expression levels were measured by quantitative real-time polymerase chain reaction. <b><i>Results:</i></b> <i>iHSP70</i> mRNA expression was significantly higher in obese subjects without MetS than in lean subjects (<i>p</i> = 0.04), whereas <i>iHSP70</i> mRNA expression was significantly lower in obese subjects with MetS than in those without MetS (<i>p</i> = 0.02) as well as in those in the lean group (<i>p</i> = 0.03). <i>iHSP27</i> mRNA expression was significantly lower in obese subjects with MetS than in those without MetS and in lean subjects (<i>p</i> = 0.037 and 0.031, respectively). <b><i>Conclusion:</i></b> We conclude that the intracellular expression levels of <i>HSP70</i> and <i>HSP27</i> may play an important role in the pathogenesis of MetS.