Effect of anthocyanins on cerebral mitochondrial functions and ischemia-induced cell death

Abstract

Introduction:Ischemia/oxygen-glucose deprivation causes changes in mitochondrial structure and function. Disturbed energy metabolism results in brain cell death - apoptosis and necrosis pathway activation. It was shown in literature, that anthocyanins reduce cytochrome c directly and block caspase activation, furthermore they act as substrates for cardiac mitochondria I complex. Currently in the scientific literature there is no data about anthocyanin affect on brain mitochondria function and ischemia-caused cell death. It is considered that compounds promoting energy metabolism recovery may have neuroprotective effect. Aim:The aim of this study is to investigate effect of cyanidin-3-O-gliucoside (Cy3G) and pelargonidin-3-O-gliucoside (Pg3G) on rat brain mitochondria oxidative pshosphorylation system and ischemia-induced cell death. Methods:In this study in vivo perfusion and in vitro global brain ischemia model were performed. Mitochondrial respirometry assays were performed using oxygraph. Cell apoptosis was determined by fluorometric measurement of caspase-3 substrate hydrolysis. Cell necrosis was detected by spectrophotometric lactate dehydrogenase activity assay. Brain tissue injury was evaluated by TTC (2,3,5-triphenyltetrazolium chloride) staining. Spectrophotometric assay for complex I of the respiratory chain was performed. Results:It was determined, that 10μM anthocyanins have neuroptotective effect without restoring of mitochondrial main function: Cy3G blocks apoptosis, Cy3G and Pg3G strongly inhibit ischemia induced necrosis. Moreover, administration of 10 μM Cy3G or Pg3G reduces brain infarct size. 20 μM Cy3G increases caspase-3 and lactate dehydrogenase activity compared with ischemic group. Also it was found, that directly added Cy3G and Pg3G inhibit non-ischemic brain mitochondria I respiratory chain complex (NADH dehydrogenase) activity