Peridroplet mitochondria regulated by perilipin 5 are involved in the
prevention of non-alcoholic steatohepatitis in mice by
Diethyldithiocarbamate
Abstract
Background and Purpose: Diethyldithiocarbamate(DDC) alleviates hepatic
inflammation and fibrosis of methionine- and choline-deficient(MCD)
diet-induced non-alcoholic steatohepatitis(NASH) in mice. Interestingly,
increased macrovesicular steatosis replace the ballooning of hepatocytes
by DDC. The therapeutic mechanism of DDC on NASH remains unclear.
Experimental Approach: C57BL/6 mice received choline-deficient, L-amino
acid-defined(CDAA) diet to induce NASH with or without DDC
treatment. Lipidomic and microarray analyses were used to find the lipid
metabolites and genes regulated by DDC. RNAscope and immunoblotting were
used to detect perilipin 5(Plin5) in the liver. Peridroplet
mitochondria(PDM) were isolated from liver tissues, stained and observed
by confocal microscope. Mixture of Oleic and palmitic acid were used to
treat C3A cells. The effect of DDC on Plin5, mitochondria-LD contact and
mitochondrial function were analyzed. Key Results: DDC alleviated
hepatic inflammation and fibrosis, whereas steatosis increased in
CDAA-diet induced NASH. Triglyceride content and genes related to
LDs and mitochondrial function increased by DDC. Plin5 which can promote
the expansion of LD and formation of PDM was upregulated in the liver by
DDC. PDM were observed in steatotic liver and have enhanced
mitochondrial function relative to cytoplasm mitochondria. DDC increased
the size of LDs and the number of PDM, and improved mitochondrial
function both in vivo and in vitro. Conclusion and Implications: PDM
promote triglyceride synthesis and reduce lipotoxicity-induced liver
injury, inflammation and fibrosis. PDM regulated by Plin5 contribute to
the therapeutic effect of DDC on NASH. The regulation of PDM may
represent an attractive pharmacological target for NAFLD.