NR1H3 (liver X receptor alpha) is a ligand-dependent nuclear receptor that functions as a master regulator of cholesterol and lipid homeostasis. Upon activation by oxysterols, NR1H3 heterodimerizes with the retinoid X receptor (RXR), shifting RXR from a silent DNA-binding partner to an active ligand-binding subunit capable of mediating transcriptional responses at LXR response elements (LXREs). NR1H3 controls cholesterol uptake by regulating MYLIP-dependent ubiquitination of lipoprotein receptors (LDLR, VLDLR, LRP8) and induces hepatic lipogenesis through LPCAT3-dependent phospholipid remodeling of endoplasmic reticulum membranes, facilitating SREBF1 processing and VLDL assembly. Additionally, NR1H3 counteracts lipid-induced ER stress and inflammation via LPCAT3-mediated modulation of SRC kinase signaling. NR1H3 variants are associated with multiple sclerosis risk; rs7120118 and rs2279238 significantly regulate NR1H3 expression across human tissues, and a rare p.Arg415Gln mutation in familial MS cases disrupts heterodimerization and transcriptional activation 12. In colorectal cancer, reduced NR1H3 expression correlates with elevated EGFR and increased proliferation 3, while in pulmonary tuberculosis patients from Punjab, NR1H3 mRNA expression is significantly downregulated 4. Recent evidence suggests silibinin protects against septic myocardial injury through NR1H3 pathway activation 5. Genetic polymorphisms in NR1H3 (e.g., rs3758672) influence vitiligo susceptibility and response to narrowband UVB phototherapy in Han Chinese populations 6. Pharmacological LXR agonists represent potential therapeutic strategies for atherosclerosis, diabetes, and inflammatory disorders 7.