Background: Insulin resistance (IR) and lipid peroxidation are accepted as ‘two-hit’ hypothesis of Non-alcoholic fatty liver disease (NAFLD). However, there are few published research on identifying genes which connect lipid and glucose metabolism by gene microarray. Objective: To identify target genes related to lipid and glucose metabolism that might be responsible for the pathogenesis of NAFLD. Methods: A rat model of NAFLD was established by feeding male rats with high-fat diet and gene expression profiles of liver tissues were determined using Agilent DNA microarray. We then investigated differentially expressed genes (DEGs) and intersection of them by using Gene Ontology (GO) and Pathway Analyses. Target genes were verified by Real-time polymerase chain reaction (RT-PCR). Results: Compared with control, 932 genes, including 783 up-regulated and 149 down-regulated, exhibited differences in expression. The up-regulated genes were involved in biosynthesis, cell development, cell differentiation and down-regulated genes contributed to biological metabolic process, adipokine metabolic pathway and insulin signaling pathway. We identified genes involved in insulin signaling pathway, Notch signaling pathway and lipid synthetic process to be closely related to liver fat accumulation and insulin resistance. Among them, IGFBP7, Notch1 and HMGCR were up-regulated (2.85-fold, 3.22-fold, and 2.06-fold, respectively, all P < 0.05) and ACACB was down-regulated (2.08-fold, P < 0.01). These four genes supposed to connect lipid and glucose metabolism after GO and Pathway analyses. Conclusions: These findings provide innovative information on the whole genome expression profile due to high-fat diet feeding, and bring new insight into the regulating effects of genes on the lipid and glucose metabolism of NAFLD.

Gut microbiota dysbiosis is an essential factor contributing to non-alcoholic fatty liver disease (NAFLD), in which the gut-liver axis plays a crucial role. Peroxisome proliferator-activated receptor δ (PPARδ) is considered a new direction for the research on NAFLD due to its positive regulation of glucose and lipid metabolism. Our experiment aimed to investigate the effect of PPARδ gene deletion on gut microbiota and NAFLD through the gut-liver axis. PPARδ-/- mice and wild-type mice were randomly divided into high-fat diet(HFD) groups and normal diet groups. In each group, six mice were sacrificed at weeks 4, 8, and 12. Metabolic indicators and inflammation indicators were measured, and the degree of liver steatosis and the ileum mucosa integrity were evaluated. Additionally, fecal samples were subjected to 16S rDNA gene sequencing and analysis of gut microbiota. Deletion of the PPARδ gene exhibited exacerbated effects on HFD-induced NAFLD and displayed more severe liver inflammation and intestinal mucosal barrier injuries. The HFD reduced the abundance of short-chain fatty acid (SCFA)-producing bacteria and increased the abundance of intestinal endotoxin-rich bacteria in mice. Deletion of the PPARδ gene exacerbated this trend, resulting in decreased abundances of norank_f__Eubacterium_coprostanoligenes_group and Alloprevotella and increased abundances of Acidibacter, unclassified_f__Comamonadaceae, unclassified_c__Alphaproteobacteria, unclassified_f__Beijerinckiaceae, unclassified_f__Caulobacteraceae, unclassified_c__Bacteroidia and Bosea. Spearman’s correlation analysis found Lachnoclostridium, unclassified_f__Rhizobiaceae, Allobaculum, Acinetobacter, Romboutsia, norank_f__Muribaculaceae and Dubosiella showed some correlations with metabolic indicators, inflammation indicators, NAS and occludin. Deletion of the PPARδ gene exacerbated HFD-induced gut microbiota dysbiosis and affected NAFLD through the gut-liver axis.

N6‑methyladenosine (m⁶A) serves a critical role in regulating gene expression and has been associated with various diseases; however, its role in the differentiation of endothelial progenitor cells (EPCs) remains unclear. The present study used liquid chromatography with tandem mass spectrometry and immunofluorescence assays to quantify the levels of m6A in human peripheral blood‑derived EPCs (HPB‑EPCs) before and after differentiation into mature cells. The present study performed Cell Counting Kit 8, Transwell, and tube formation assays to determine the effects of overexpression and knockdown of Wilms' tumor 1‑associated protein (WTAP) on HPB‑EPCs. The results revealed that the level of m⁶A modification was significantly increased during HPB‑EPCs differentiation, and WTAP exhibited the most significant alteration among the enzymes involved in m⁶A regulation. When WTAP was overexpressed in HPB‑EPCs, cell proliferation, invasion, and the formation of tubes were improved, whereas WTAP knockdown yielded the opposite effects. In conclusion, the present study highlighted the involvement of m⁶A in regulating EPC differentiation, with WTAP acting as a promoter of EPC differentiation.