Fig. 4: Allogeneic hepatocyte transplantation using lentivirus-mediated Trim31 expression alleviates HFD-triggered hepatic steatosis, insulin resistance, and inflammation.

Preconditioned liver-specific Trim31 deletion (THKO) mice with an 8-week HFD treatment as donors were transduced (THKO)(LV−). The hepatocytes isolated from the (THKO)(LV−) group mice were transduced with a lentivirus-loaded full-length Trim31 sequence. The corresponding blank vector was transduced as controls. Then the additional HFD-fed THKO mice as recipient were injected with transduced hepatocytes via the portal vein. The HFD-fed transplanted (THKO)(LV+) mice were harvested for further experimental detection. a The strategy diagram for ex vivo gene therapy used in the current study. b Records for the liver weight, body weight, and the ratio of liver weight/body weight (%) of the HFD-fed recipient (THKO)(LV−) and (THKO)(LV+) mice at the last week of HFD treatment (n = 25 mice per group) (**P < 0.01 vs. HFD-fed recipient (THKO)(LV−) groups). c Representative pictures for liver appearance and Oil red O staining, H&E staining, and PAS staining-indicated liver histopathologic changes of the HFD-fed recipient (THKO)(LV−) and (THKO)(LV+) mice after ex vivo experiment (magnification, ×100; n = 10 images per group for each staining). d Liver function markers ALT and AST levels were detected in transduced recipient mice (n = 25 mice per group) (**P < 0.01 vs. HFD-fed recipient (THKO)(LV-) groups). e, f Records for the glucose tolerance test (GTT) (e) and insulin tolerance test (ITT) (f), and the corresponding fasting insulin levels and HOMA-IR index in the HFD-fed recipient (THKO)(LV−) and (THKO)(LV+) mice after transplantation (n = 25 mice per group) (**P < 0.01 vs. HFD-fed recipient (THKO)(LV−) groups). g Liver lipid contents including TG, TC, and NEFA of the transduced mice (n = 25 mice per group) (**P < 0.01 vs. HFD-fed recipient (THKO)(LV−) groups). h qPCR analysis of the relative mRNA expression of genes associated with fatty acid uptake, synthesis, and β-oxidation in the HFD-fed recipient (THKO)(LV−) and (THKO)(LV+) mice after transplantation (n = 10 liver samples per group) (**P < 0.01 vs. HFD-fed recipient (THKO)(LV-) groups). i, j Representative immunoblotting bands for expression alterations of total amounts and phosphorylated forms of critical indicators involved in insulin signaling (i), including IRS1, p-IRS1(Ser307), p-IRS1(Tyr608), AKT, and p-AKT, and Rhbdf2–MAP3K7 axis and p-NF-κB pathway (j) in the liver of HFD-fed recipient (THKO)(LV−) and (THKO)(LV+) mice (n = 4 per experiment) (**P < 0.01 vs. HFD-fed recipient (THKO)(LV−) groups). The GAPDH was used as a loading control. Data are expressed as mean ± SEM. The relevant experiments presented in this part were performed independently at least three times. Significance determined by Student’s two-tailed t test analysis.