Improvment of high fat diet induced metabolic dysfunction-associated fatty liver disease of mice by leucine
10.3867/j.issn.1000-3002.2025.08300
- VernacularTitle:亮氨酸对高脂饮食诱导小鼠代谢相关脂肪性肝病的改善作用及机制
- Author:
Yizhi DING
1
;
Huiwen ZHAO
;
Shan SHAN
;
Liwen ZHANG
;
Xiulan ZHAO
Author Information
1. 山东大学公共卫生学院毒理与营养系，山东 济南 250012
- Publication Type:Journal Article
- Keywords:
leucine;
metabolic dysfunction-associated fatty liver disease;
energy metabolism;
fat synthesis
- From:
Chinese Journal of Pharmacology and Toxicology
2025;39(5):343-351
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE To explore the effect and underlying mechanism of leucine(Leu)on meta-bolic dysfunction-associated fatty liver disease induced by high fat diet(HFD)in mice.METHODS C57BL/6J male mice were randomly divided into chow diet(normal),chow diet+Leu(normal+Leu),HFD and HFD+Leu groups,with 10 mice in each group.The mice in the normal and normal+Leu groups received chow diet while those in the HFD and HFD+Leu groups received HFD.Drinking water for mice in the normal+Leu and HFD+Leu groups was supplemented with 1.5%Leu.The experiment lasted 24 weeks,total food and water intake of mice were recorded weekly to calculate energy and Leu intake respectively.Energy metabolism of mice was detected at week 20 by the Oxymas/CLAMS Animal Metabolic System heat production,CO2 exhalation,O2 consumption and respiratory exchange rate(RER).At the end of week 24,the mice were sacrificed and the livers were harvested,followed by the oil red O staining to reveal the fat content.Western blotting was performed to analyze the changes in the activity of the liver branched-chain α-keto acid dehydrogenase E1α(BCKDE1A),the activation of AMP-activated protein kinase alpha subunit(AMPKα),and the protein expressions of downstream effector molecules including silent information regulator 1(SIRT1)and peroxisome proliferator-activated receptor coactivator-1α(PGC-1α),fatty acid synthetase(FAS)and fatty acid binding protein 4(FABP4)in the liver of mice.RESULTS Total Leu intake of mice was significantly reduced in the HFD+Leu group,compared with the normal+Leu group.The mice fed with HFD significantly increased the energy intake body mass gain and liver mass,accompanied by fat accumulation in the liver,compared to the mice in the normal group.Simultaneously,the mice in the HFD group showed a decrease in CO2 exha-lation both by day and by night,and in the respiratory exchange ratio by day compared to the normal group.Compared with the HFD group,the body mass gain and liver mass obviously decreased in mice of the HFD+Leu group,and the liver fat accumulation was reduced.The mice in the HFD+Leu group exhib-ited higher heat production and O2 consumption,along with an increase in CO2 exhalation by day and by night.In addition,heat production,CO2 exhalation,and O2 consumption were significantly higher by night than by day(P<0.01).As for the respiratory exchange ratio,a night increase was seen in the mice from the normal group,normal+Leu group,and HFD group,but not in the HFD+Leu group.The results of Western blotting showed that compared with the normal group,the BCKDE1A phosphorylation inacti-vation was enhanced,AMPKα phosphorylation activation alleviated,the protein expressions of SIRT1 and PGC-1α downregulated(P<0.05),and the protein expressions of FAS and FABP4 increased in the livers of mice in the HFD group.Compared with the HFD group,the BCKDE1A phosphorylation inacti-vation was alleviated,AMPKα phosphorylation activation enhanced,the protein expressions of SIRT1 and PGC-1α increased,and the protein expressions of FAS and FABP4 downregulated in the livers of mice in the HFD+Leu group.CONCLUSION Leu can alleviate HFD-induced metabolic dysfunction-associated fatty liver disease in mice,which may be closely related to the promotion of energy metabo-lism and inhibition of fat synthesis.
