Diethyldithiocarbamate improves lipotoxic injury of hepatocytes by regulating Perilipin 5

Abstract

Abstract: Objective To investigate the molecular mechanism of diethyldithiocarbamate (DDC) ameliorating fatty acid-induced lipotoxic injury of hepatocytes. Methods Lipotoxic model of LO2 cells was induced by 0.5mM palmitic acid (PA) (PA group), and treated with 300μM DDC (DDC+PA group) at the same time, while a corresponding control group was established. Quantitative real-time PCR was performed to measure the mRNA levels of TNF-α, CHOP, ATF4 and BAX. Mitochondrial membrane potential was assessed using JC-1 staining. Real-time PCR and Western blot were used to detect the expression of Perilipin5 (Plin5) gene and protein. The content of lipid droplets and their interaction with mitochondria were visualized through staining of lipid droplets and mitochondria. SiRNA interference was used to knockdown Plin5. The effects of DDC on mitochondrial-lipid droplet interaction, inflammation, endoplasmic reticulum stress and apoptosis-related genes, mitochondrial membrane potential, were observed after Plin5 knockdown. Results Compared with the control group, the expression of TNF-α, CHOP, ATF4 and BAX were increased in PA group [(1.436 ± 0.447) vs (37.762 ± 9.715), (1.005 ± 0.024) vs (20.892 ± 2.721), (1.467 ± 0.332) vs (15.184 ± 7.006), (2.095 ± 0.814 ) vs (29.480 ± 13.564)] (P<0.05). Compared with the PA group, the expression of TNF-α, CHOP, ATF4 and BAX were decreased in DDC+PA group [(37.762 ± 9.715) vs (2.890 ± 0.939), (20.892 ± 2.721) vs (12.56 ± 4.175), (15.184 ± 7.006) vs (3.41 ± 1.159), (29.480 ± 13.564) vs (8.462 ± 5.441)] (P<0.05). Compared with the control group, the mitochondrial membrane potential (MP) was decreased in PA group [(2.341 ± 0.491) vs (0.805 ± 0.214)] (P<0.05), whereas increased significantly in DDC+PA group compared with the PA group [(0.805 ± 0.214) vs (1.507 ± 0.292)] (P<0.05). Compared with the PA group, the expression of Plin5 was increasedin DDC+PA group [(1.567 ± 0.152) vs (3.807 ± 0.579)] (P<0.05). Compared with the PA group, the content of lipid droplet and the contact between mitochondria and lipid droplets were increased in the DDC+PA group [(3.123 ± 1.102) vs (9.795 ± 1.740), (0.362 ± 0.100) vs (2.550 ± 0.521)] (P<0.05). Plin5 knockdown blocked the effects of DDC on the interaction of mitochondria-lipid droplet, TNF-α, CHOP, ATF4, BAX, and mitochondrial membrane potential in LO2 cells (P<0.05). Conclusion DDC promotes mitochondria-lipid droplet interaction, and improves PA-induced lipotoxic injury of hepatocytes through regulating Plin5.

Key words: Diethyldithiocarbamate, Lipotoxicity, Perilipin 5, Mitochondrion, Metabolic dysfunction associated fatty liver disease

SUN Xiang-yun, YU Qing-hong, QI Yi-fei, BAI Shi-jin, LIU Tian-hui. Diethyldithiocarbamate improves lipotoxic injury of hepatocytes by regulating Perilipin 5[J]. Chinese Hepatolgy, 2025, 30(4): 537-541.

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