[Quantitative detection and clinical value of CD44 in patients with nonalcoholic fatty liver disease]

Objective: To quantitatively detect CD44 expression in patients with nonalcoholic fatty liver disease (NAFLD) for comparative analysis. Methods: Patients with chronic liver diseases accompanied with or without NAFLD, including chronic hepatitis B, cirrhosis and hepatocellular carcinoma after chronic hepatitis B, and healthy blood donors as normal controls who admitted to the Affiliated Hospital of Nantong University from May to October 2018 were selected. The proportion of CD44 positive cells was analyzed by flow cytometry. CD44 level was quantified by an enzyme-linked immunosorbent assay, and the biochemical indicators such as serum aspartate aminotransferase, alanine aminotransferase activity, total cholesterol and triglyceride were routinely analyzed. The cancerous and adjacent cancerous tissues of patients accompanied with or without NAFLD were collected by self-matching method and analyzed by immunoblotting and histochemistry and compared by CD44 integrated optical density. Image-Pro Plus version 6.0, Image J, GraphPad Prism 5.0, Photoshop, Microsoft Excel and IBM SPSS statistics 23 were used to analyze and draw pictures. An independent sample t-test was used to compare the differences between groups. Results: Patients accompanied with NAFLD had hepatocyte injury and dyslipidemia. NAFLD and chronic liver disease patients had significantly elevated serum CD44 levels than normal control group (P < 0.01). CD44 positive lymphocyte ratio was 78.19 % ± 16.33 % in NAFLD patients and 68.47% ± 20.91% in chronic hepatitis B group, which was higher than the control group (46.51% ± 20.52%). Chronic hepatitis B group with steatosis had significantly higher CD44 concentration (181.42 ± 49.36) ng/ml than chronic hepatitis B group (142.52 ± 53.87) ng/ml and normal control group (99.47 ± 15.23) ng/ml. CD44/GAPDH ratio in the liver cancer group (1.306 ± 0.614) was significantly higher than paracancerous group (0.477 ± 0.291) and the difference between the two groups was statistically significant (t = 3.451, P = 0.004). The integrated optical density of CD44 in the NAFLD-related liver cancer and paracancerous group were 25.721 ± 5.881 and 14.155 ± 4.001 and the difference between the groups was statistically significant (t = 14.544, P < 0.001). The pathological features of high expression of CD44 in patients with hepatocellular carcinoma were significantly correlated with HBV infection, tumor size, single/multi-center, and lymph node metastasis, degree of differentiation, TNM grade, Child-Pugh score, portal vein tumor thrombus and extrahepatic metastasis. HCC patients with NAFLD had significantly higher serum CD44 (234.62 ± 69.40) ng/ml than patients without NAFLD (186.49 ± 58.89) ng/ml (t = -3.191, P = 0.002), but there was no statistically significant difference in the clinicopathological characteristics between the high/low CD44 groups of HCC patients with NAFLD. Conclusion: The results suggest that CD44 is abnormally activated and its mechanism may play an important role in the progression of NAFLD.

[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.

[Advances in epidemiology and serum markers for the noninvasive diagnosis of nonalcoholic fatty liver disease]

The global prevalence rate of nonalcoholic fatty liver disease (NAFLD) has increased year by year, and it has become the number one cause for chronic liver disease in China. In addition, the trend of NAFLD has become more pronounced and evident in female gender and younger age group. The long-term persistence of fatty liver disease may cause serious consequences. There are no accepted diagnostic criteria for diagnosing noninvasive diagnosis of NAFLD. Alpha-ketoglutarate is a newly discovered serological marker of high diagnostic value and considered the most valuable potential biomarker along with cytokeratine-18 (CK-18).

[The role of cytochrome P450 in nonalcoholic fatty liver induced by high-fat diet: a gene expression profile analysis]

Objective: To clarify the role of cytochrome P450 in nonalcoholic fatty liver disease (NAFLD) by RNA-Seq and bioinformatics analysis. Methods: A total of 20 male C57BL/6 mice were used. Ten mice were fed with high-fat diet (D12492, 60% kcal fat) for 16 weeks to establish a mouse model of NAFLD, and the other 10 mice were fed with low-fat diet (D12450B, 10% kcal fat) as control group. At the end of the experiment, the body weight, liver weight, and hepatic triglyceride (TG) content were measured. Meanwhile, HE staining and RNA-Seq analysis were performed for the liver tissues. The differentially expressed genes were screened out and subjected to bioinformatics analysis, including KEGG and GO BP enrichment analyses and interaction network analysis. Comparison of means between the two groups was made using t-test. Results: Compared with the control group, the mice in the model group were obviously obese, with significantly increased body weight (41.41 ± 6.01 g vs 28.78 ± 1.79 g, t = 6.04, P < 0.01) and liver weight (1.38 ± 0.30 g vs 1.08 ± 0.10 g, t = 2.89, P < 0.01). The mice in the model group showed obvious steatosis, accompanied by a small amount of inflammatory cell infiltration, but with no obvious fibrosis, according to the results of HE staining. In addition, the hepatic TG content in the model group was significantly increased compared with that in the control group (0.64 ± 0.01 mg/mg vs 0.29 ± 0.06 mg/mg, t = 10.11, P = 0.04). Compared with the control group, a total of 367 differentially expressed genes, including 211 down-regulated and 156 up-regulated ones, were identified in the model group according to the RNA-seq results. Meanwhile, 19 CYP450 subtypes, accounting for 5% of the differentially expressed genes, were identified, and CYP2E1, CYP2C70, CYP3A11, CYP3A25, CYP2D26, CYP4A10, CYP17A1, CYP2B10, and CYP2C38 were involved in oxidative stress, steroid hormone metabolism, fatty acid metabolism, arachidonic acid metabolism, and the PPAR signaling pathway. An interaction network was constructed with 30 nodes, and CYP2E1 and CYP2C70 were identified as key nodes. RT-PCR validation results showed that the expression changes of CYP450 subtypes and lipid metabolism-related genes were consistent with the findings of sequencing. Conclusion: The CYP450 family plays a vital role in the pathogenesis of fatty liver by regulating lipid metabolism-related pathways, including oxidative stress, arachidonic acid metabolism, steroid hormone metabolism , and fatty acid metabolism.