[Study on the correlation between small intestinal dendritic cells and non-alcoholic fatty liver disease in mice]

Objective: To preliminary, explore the effect of small intestinal epithelial dendritic cells on the occurrence and development of nonalcoholic fatty liver disease in mice. Methods: Thirty-two (half male and half female) 4-week-old C57BL/6 mice were randomly divided into two groups. The mice were fed with normal diet (SD group) and high-fat diet (HFD group). Eight mice (half male and half female) were randomly killed from each group over the 14 and 20-weeks feeding period to observe their body weight, liver and small-intestine wet weight. Alanine aminotransferase, aspartate aminotransferase, blood glucose, high-density lipoprotein, low-density lipoprotein, total cholesterol and triglyceride were determined by eyeball blood samples. Pathological diagnosis and alcoholic fatty liver disease activity score were collected. The number of mice small intestinal dendritic cells was observed under a microscope. Statistical analysis was performed to compare two groups of independent samples with homogeneity test of variance, t test, and covariance analysis. Results: The body weight, liver wet weight, serum alanine aminotransferase and aspartate aminotransferase of mice in HFD group were significantly higher than those of control group at 20 weeks (P < 0.05), and the serum high density lipoprotein of mice in HFD group was significantly higher than that of SD group at 14 weeks (P < 0.05). At 14th weeks, the liver tissue of mice in HFD group had early pathological manifestations of hepatitis (fatty degeneration, punctate necrosis and balloon-like degeneration). Of which 87.5% (7/8) of them were diagnosed as non-alcoholic steatohepatitis or non-alcoholic fatty liver disease, while only a few mice in SD group had early pathological manifestations of hepatitis. At 20th weeks, all mice in HFD group were diagnosed with non-alcoholic steatohepatitis or non-alcoholic fatty liver disease, while none of the mice in SD group was diagnosed with non-alcoholic fatty liver disease. At both time points, the percentage of small intestinal dendritic cells in HFD group was significantly higher than that in SD group (14 weeks: 4.181 ± 4.314 vs. 15.099 ± 10.349; 20 weeks: 9.615 ± 8.267 vs. 32.839 ± 24.475, both P < 0.05). Statistical analysis combined with the alcoholic fatty liver disease activity score showed that there was no linear correlation between the two groups (regression coefficient was 20.196%). Conclusion: The number and different staging of small intestinal dendritic cells in mice is associated with the occurrence and development of NAFLD.