Restoration of lipid homeostasis between TG and PE by the LXRα-ATGL/EPT1 axis ameliorates hepatosteatosis

• Published in: Cell death & disease Vol. 14; no. 2; p. 85
• Main Authors: Chen, Yulian, Jiang, Huanguo, Zhan, Zhikun, Lu, Jindi, Gu, Tanwei, Yu, Ping, Liang, Weimin, Zhang, Xi, Liu, Shuwen, Bi, Huichang, Zhong, Shilong, Tang, Lan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 06-02-2023; Springer Nature B.V; Nature Publishing Group
• Subjects: 13/89; 59; 59/5; 59/57; 64/110; 692/699/2743/2099; 692/699/2743/393; Animals; Antibodies; Biochemistry; Biomedical and Life Sciences; Body mass index; Cell Biology; Cell Culture; Enzymes; High fat diet; Homeostasis; Homeostasis - physiology; Immunology; Life Sciences; Lipid Metabolism - genetics; Lipids; Liver X receptors; Liver X Receptors - genetics; Liver X Receptors - metabolism; Medical prognosis; Metabolic syndrome; Metabolism; Mice; Mice, Knockout; Obesity; Phosphatidylethanolamine; Phosphatidylethanolamines; Triglycerides - metabolism
• ISSN: 2041-4889; 2041-4889
• DOI: 10.1038/s41419-023-05613-6

Converting lipid disturbances in response to energy oversupply into healthy lipid homeostasis is a promising therapy to alleviate hepatosteatosis. Our clinical studies found that a further elevation of triglyceride (TG) in obese patients with the body mass index (BMI) greater than 28 was accompanied by a further reduction of phosphatidylethanolamine (PE). Shorter survival and poor prognosis were shown for the patients with high TG and low PE levels. Liver X receptor alpha (
LXRα
) knockout mice aggravated high-fat diet (HFD)-induced obesity and lipid disorders, making the TG enrichment and the PE decrease more pronounced according to the liver lipidomics analysis. The RNA-seq from mice liver exhibited that these metabolism disorders were attributed to the decline of
Atgl
(encoding the TG metabolism enzyme ATGL) and
Ept1
(encoding the PE synthesis enzyme EPT1) expression. Mechanistic studies uncovered that LXRα activated the
ATGL
and
EPT1
gene via direct binding to a LXR response element (LXRE) in the promoter. Moreover, both the supplement of PE in statin or fibrate therapy, and the LXRα inducer (oridonin) ameliorated cellular lipid deposition and lipotoxicity. Altogether, restoration of lipid homeostasis of TG and PE via the LXRα-ATGL/EPT1 axis may be a potential approach for the management of hepatosteatosis and metabolic syndrome.