Curcumin Alleviates Chromium-induced Mitochondrial Metabolism Disturbance In Duck Intestinal Epithelial Cells Through AMPK/PINK1/Parkin Pathway

This paper aims to investigate the therapeutic effect of curcumin on the disruption of metabolism in duck intestinal epithelial cells induced by hexavalent chromium(Cr(VI))exposure.The relationship between mitochondrial autophagy and energy metabolism was investigated using the PINK1 activator valinomycin.The experiment was divided into six experimental groups: control group,chromium group(16 μM Cr),chromium+curcumin group(16 μM Cr + 10 μM Cur),curcumin group(10 μM Cur),Valinomycin group(,8 μM Valinomycin),Cr+Valinomycin group(16 μM Cr+8 μM Valinomycin)The cell status and damage were observed using ordinary light microscopy and electron microscopy;the key enzymes of the tricarboxylic acid cycle,citrate synthase(CS)and malate dehydrogenase(MDH),were detected.The relative activity of citrate synthase(CS)and malate dehydrogenase(MDH),the mitochondrial membrane potential(JC-1)fluorescence staining,and the relationship between mitochondrial metabolism and autophagy by co-localization of PGC-1α and LC3 were also assessed by q PCR,PGC-1α,HK2,G-6-pase,PEPCK,GLUT2,PPARγ,CPT-1α)by q PCR,and mitochondrial autophagy proteins(PINK1,Parkin,LC3Ⅰ and LC3Ⅱ)and energy metabolism proteins(AMPK,p-AMPK,PGC-1α,HK2,GLUT2,PPARγ)expression.The results showed that Cr(VI)exposure led to mitochondrial damage in intestinal epithelial cells,decreased membrane potential,inhibition of mitochondrial autophagy and decreased activity of key enzymes related to the tricarboxylic acid cycle.Compared with the Cr group,the Cr+Cur group showed a significant increase in protein expression of genes related to mitochondrial autophagy and energy metabolism,an increase in mitochondrial membrane potential and an increase in the activity of key enzymes related to the tricarboxylic acid cycle,as well as a positive correlation between PGC-1α and LC3 co-localization,indicating a positive correlation between mitochondrial autophagy and mitochondrial energy metabolism.It can activate mitochondrial autophagy.The results of the Cr+Valinomycin group were similar to those of the Cr+Cur group compared to the Cr group.This suggests that Valinomycin can alleviate the disruption of energy metabolism in duck small intestine cells induced by Cr(VI)exposure by activating the PINK1/Parkin-mediated mitochondrial autophagy pathway.The above results showed that Cr(VI)inhibited mitochondrial autophagy in duck small intestine epithelial cells and caused disruption of energy metabolism.The mitochondrial autophagy disorder induced by Cr(VI)was alleviated by curcumin through activation of the PINK/Parkin-mediated mitochondrial autophagy pathway.