To evaluate the relationship between GLP-1R gene polymorphisms and type 2 diabetes mellitus with dyslipidemia and without dyslipidemia in China. A total of 200 patients with Type 2 Diabetes Mellitus (T2DM) were included in this study, including 115 with dyslipidemia and 85 without dyslipidemia. We used Sanger double deoxygenation terminal assay and PCR-RFLP to detect genotype of the GLP-1R rs10305420 and rs3765467 loci. T-test was used to analyze the association between gene polymorphisms and lipid indicators. SHEsis online analysis software was used to analyze the linkage balance effect of loci, and SPSS 26 was used to calculate the gene interaction by dominant model. The genotype distribution of the two loci in the sample of this study was in accordance with Hardy-weinberg equilibrium. There were significant differences in the genotype distribution and allele frequency of rs3765467 between T2DM patients with and without dyslipidemia (GG 52.9%, GA + AA 47.1% vs. GG 69.6%, GA + AA 30.4%; P = 0.017). Under the dominant model, the effects of rs3765467 A allele and rs10305420 T allele on dyslipidemia had multiplicative interactions (P = 0.016) and additive interactions (RERI = 0.403, 95% CI [-2.708 to 3.514]; AP = 0.376, 95% CI [-2.041, 2.793]). Meanwhile, HbA_1c levels in rs3765467 A allele carriers (GA + AA) were found to be significantly lower than those in patients with GG genotype (P = 0.006). The rs3765467 (G/A) variant is associated with the incidence of dyslipidemia, and G allele may be a risk factor for dyslipidemia.

To investigate the mechanism of liraglutide affecting lipid metabolism by regulating lipolysis and lipogenesis in cells and ob/ob mice. 3 T3-L1 cells were treated with liraglutide in vitro, and differentially expressed genes were screened by RNA sequencing. Gene Ontology (GO) and KEGG (Kvoto Encyclopedia of Genes and Genomes) enrichment analyses identified target genes for lipid regulation of liraglutide. 3 T3-L1 preadipocytes were induced to differentiate into adipocytes using a "cocktail method". Western blot and immunofluorescence were used to detect the expression of target genes and the lipid regulatory effect of liraglutide. 3 T3-L1 preadipocytes were transfected with lentivirus overexpressing Zbtb20 to study its role in adipogenesis, and gene expression was analyzed by RT-qPCR and Western blot. In vivo, ob/ob mice were subcutaneously injected with liraglutide or saline for 4 weeks. Blood lipids, adipose tissue volume and adipocyte size were detected. Immunohistochemical analysis and RT-qPCR were used to detect the expression of target genes in adipose tissue. Liraglutide reduced lipid droplets and TG levels and altered the expression of genes related to fatty acid metabolism, lipogenesis, fatty acid oxidation, and adipocyte browning. The results of PCR, Western blot and immunofluorescence confirmed that liraglutide could regulate the adipogenesis by downregulating the transcriptional suppressor ZBTB20, and overexpression of Zbtb20 inhibited the expression of LPL, the key enzyme for lipohydrolysis. Liraglutide regulates lipid metabolism through ZBTB20-LPL pathway to reveal its molecular mechanism.