Cytochrome c oxidase as the target of the heat shock protective effect in septic liver.
Liver function failure is one of the characteristics of critically ill, septic patients and is associated with worse outcome. Our previous studies have demonstrated that heat-shock response protects cells and tissue from subsequent insults and improves survival during sepsis. In this study, we have shown that mitochondrial cytochrome c oxidase (CCO) is one of the major sources of that protective effect. Experimental sepsis was induced by the cecal ligation and puncture (CLP) method. Heat-shock treatment was induced in rats by hyperthermia 24 h before CLP operation. The results showed that ATP content of the liver declined significantly, and the enzymatic activity of mitochondrial CCO was apparently suppressed during the late stages of sepsis. The mitochondrial ultrastructure of septic liver showed the deformity, mild swelling and inner membrane budding. Heat-shock treatment led to heat-shock protein 72 overexpression and prevented the downregulation of Grp75 during sepsis. On the contrary, the expression of the enzyme complex and its activity were preserved, associated with the minimization of ultrastructural deformities. In conclusion, the maintenance of mitochondrial function, especially the CCO, may be an important strategy in therapeutic interventions of a septic liver.
Chen
Hsiang-Wen
HW
Department of Microbiology, School of Medicine, Kaohsiung Medical University, Kaohsiung City, Taiwan.
Kuo
Hung-Tien
HT
Lu
Tzong-Shi
TS
Wang
Shu-Jung
SJ
Yang
Rei-Cheng
RC
D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D015536:Down-Regulation / Q000502:physiology; D003576:Electron Transport Complex IV / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000032:analysis; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000032:analysis; D018869:Heat-Shock Response / Q000502:physiology*; D008107:Liver Diseases / Q000378:metabolism* / Q000473:pathology / Q000628:therapy; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D008854:Microscopy, Electron; D008930:Mitochondria, Liver / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018805:Sepsis / Q000378:metabolism / Q000628:therapy
D018840:HSP70 Heat-Shock Proteins; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; C018551:glucose-regulated proteins; D000255:Adenosine Triphosphate; D003576:Electron Transport Complex IV