Figure 7.

PRMT6 in macrophages suppresses liver fibrosis. (A–C) Cells (liver macrophages (A), endothelial cells (EC) (B), or hepatic stellate cells (HSC) (C)) isolated from Prmt6^-/- (KO) mice were treated with control vector or vector expressing Prmt6 at indicated concentrations. N = 3–4 mice. ns, not significant. ∗P < .05, ∗∗P < .01, ∗∗∗P < .001. Prmt6 expression is presented relative to WT cells. (A, bottom) TGF-β1 and PRMT6 protein levels in cells expressing Prmt6. Cells overexpressing PRMT6 are marked with asterisks. (D) Liver macrophages from WT or KO mice were used in a co-culture experiment with WT HSCs for 24 hours in the presence of 5 μg/mL of TGF-B1 antibodies or control immunoglobulin G. Relative gene expression in HSCs, ∗∗P < .01. N = 4. (E and F) Prmt6^-/- (KO) mice were fed Western diet with alcohol in the drinking water (WDA, alcohol) for 12 weeks. Mice were treated with chlodronate liposomes and 1 day later were injected with 10⁶ BMDM per mouse. Shortly after (within 1 hour after injection) mice liver biopsy was collected. Then mice were fed Western diet and alcohol for 4 more weeks. (E) Schematic of performed procedures. (Bottom left) Gene expression in liver biopsies from mice that received WT or KO macrophages as percent expression of a WT mouse. (Bottom right) International normalized ratio and prothrombin time in mice before chlodronate injection and after 16 weeks of feeding. N = 3 per group. ∗∗∗P < .001 paired t test. (F, left) Sirius red staining of biopsy and corresponding liver sections. Corresponding sections were placed on the same slide and stained simultaneously. Bars, 100 μm. (Right) Percent positive area of Sirius red staining. ns, not significant. ∗P < .05. (Bottom) Fold change in liver mRNA during last 4 weeks of feeding. ∗P < .05.