1-benzyl-6-nitro-4-phenyl-4-(methoxycarbonyl)-2(1H)-pyridinone, a novel pirfenidone derivative, alleviate hepatic fibrosis through T cells

Abstract

Hepatic fibrosis (HF) is a pathological process in many liver diseases, which lack of specific agents. Pirfenidone (PFD) derivatives are potential new drug. The purpose of this study was to investigate the effect and immunological mechanism of PFD derivatives on HF. A total of 11 PFD derivatives were designed, synthesized and screened. 1-benzyl-6-nitro-4-phenyl-4-(methoxycarbonyl)-2(1 H)-pyridinone (code: Compound 5) had optimal effect on inhibiting nitric oxide release, hepatic stellate cells (HSCs) and T cell proliferation, which suggested that Compound 5 showed anti-inflammatory, anti-fibrosis and immunoregulation effects. Compound 5 inhibited the proliferation of HSC-T6 and T cell in dose-dependent manner, the IC₅₀ was 10.19 μM and 17.16 μM, respectively. Compound 5 inhibited the differentiation of CD8⁺T cells and promoted the differentiation of T_regs in the splenic T lymphocyte of CCl₄-induced mouse HF model. Besides, Compound 5 promoted HSC-T6 apoptosis in dose-dependent manner, accompanied by the down-regulation of α-smooth muscle actin (α-SMA) and collagen-I (Col-I). In terms of mechanism, Compound 5 had no significant effect on glucose uptake of T cells. But it inhibited non-esterified fatty acid (NEFA) secretion of T cell by inhibiting the phosphorylation of PI3K-AKT-mTOR signal, which related to the metabolism of T cell. Subsequently, Compound 5 affected α-SMA and Col-I expression of HSC-T6 by T cell modulating in cell co-culture.

Conclusion

Compound 5 is a promising new drug against HF by the dual role of inhibiting HSCs and modulating T cells lipid metabolism, which affects the immune microenvironment of HF.