Hepatic stellate cell (HSC) activation is a key phenomenon in development of liver fibrosis. Recently, Akkermansia muciniphila has been introduced as a next-generation microbe residing in the mucosal layer of the human gut. Due to the probable risks associated with the use of live probiotics, the tendency to use heat-killed bacteria has been raised. Herein, we investigated the potential anti-fibrotic effects of heat-killed A. muciniphila MucT on activation of HSCs. The human LX-2 cells were stimulated by various concentrations of LPS to evaluate the optimal concentration for HSC activation. Cell viability of LX-2 cells treated with LPS and heat-killed A. muciniphila MucT was measured by MTT assay. Scanning electron microscopy was used to analyze the morphology of heat-killed bacteria. Quiescent and LPS-stimulated LX-2 cells were coinfected with heat-killed A. muciniphila MucT. The gene expression of α-SMA, TIMP, Col1, TGF-β, TLR4, and PPARγ was analyzed using quantitative real-time PCR. Our results showed that LPS treatment led to a significant increase in fibrosis markers in a concentration-independent manner (P < 0.0001), and significantly downregulated the expression of PPARγ (P < 0.0001). The heat-killed A. muciniphila MucT could significantly modulate the expression of fibrosis markers particularly in MOI 10 (P < 0.0001), and reversed the HSC activation in LPS-stimulated LX-2 cells. In conclusion, we demonstrated that heat-killed A. muciniphila MucT was safe and capable to ameliorate LPS-induced HSC activation through modulation of fibrosis markers. Further in vivo studies are required to validate the anti-fibrotic properties of heat-killed A. muciniphila MucT.

肝星状细胞 (HSC) 激活是肝纤维化发展的关键现象。最近，Akkermansia muciniphila已被引入作为居住在人类肠道粘膜层中的下一代微生物。由于与使用活益生菌相关的可能风险，使用热灭活细菌的趋势有所增加。在此，我们研究了热灭活的A. muciniphila MucT 对 HSC 活化的潜在抗纤维化作用。用不同浓度的 LPS 刺激人 LX-2 细胞，以评估 HSC 活化的最佳浓度。用 LPS 和热灭活A. muciniphila处理的 LX-2 细胞的细胞活力MucT通过MTT测定法测量。扫描电子显微镜用于分析热灭活细菌的形态。静止和 LPS 刺激的 LX-2 细胞与热灭活的A. muciniphila MucT共感染。使用实时定量 PCR 分析 α-SMA、TIMP、Col1、TGF-β、TLR4 和 PPARγ 的基因表达。我们的结果表明，LPS 治疗导致纤维化标志物以浓度独立的方式显着增加（P  < 0.0001），并显着下调 PPARγ 的表达（P  < 0.0001）。热灭活的A. muciniphila MucT 可以显着调节纤维化标志物的表达，尤其是在 MOI 10 ( P < 0.0001)，并逆转 LPS 刺激的 LX-2 细胞中的 HSC 激活。总之，我们证明了热灭活的A. muciniphila MucT 是安全的，并且能够通过调节纤维化标志物来改善 LPS 诱导的 HSC 活化。需要进一步的体内研究来验证热灭活A. muciniphila MucT的抗纤维化特性。