Cardiac complex II activity is enhanced by fat and mediates greater mitochondrial oxygen consumption following hypoxic re-oxygenation.

Cardiac complex II activity is enhanced by fat and mediates greater mitochondrial oxygen consumption following hypoxic re-oxygenation. Pflugers Arch. 2020 Feb 20;: Authors: Zhu SC, Chen C, Wu YN, Ahmed M, Kitmitto A, Greenstein AS, Kim SJ, Shao YF, Zhang YH Abstract Recent evidence suggests that mitochondrial complex II is an essential mediator of myocardial ischemia-reperfusion injury. The present study aimed to investigate the effects of fatty acid supplementation or high-fat diet (HFD) on cardiac mitochondrial activity. The changes of complex I and complex II activities and mitochondrial oxygen consumption rate (OCR) following hypoxia and re-oxygenation under these conditions were studied. Our results have shown that OCR (mitochondrial activity) was significantly increased with palmitoylcarnitine supplementation in mitochondria-enriched fraction from C57BL/6 mice hearts. Mitochondrial complex I activity was unaffected by palmitoylcarnitine but complex II activity was enhanced. Re-oxygenation following 30-min hypoxia transiently increased OCR but such an effect on OCR was abolished by complex II inhibitor, malonate, but not by complex I inhibitor, rotenone, despite that complex I activity was significantly increased with re-oxygenation following hypoxia in the presence of palmitoylcarnitine. Furthermore, OCR and complex II activity were significantly increased in the mitochondria from high-fat diet mice heart compared with those of...
Source: Pflugers Archiv : European Journal of Physiology - Category: Physiology Authors: Tags: Pflugers Arch Source Type: research