P38γ drives aerobic glycolysis in liver sinusoidal endothelial cells and regulates alcoholic liver disease via the PFKFB3 signaling pathway.

OBJECTIVES

During alcoholic liver disease (ALD), alcohol induces functional impairment of LSECs, thereby exacerbating inflammation and fibrosis. This research aims to investigate whether P38γ drives aerobic glycolysis in LSECs via the PFKFB3 signaling axis, thereby participating in the progression of ALD.

METHODS

An ALD cell model was established by treating primary hHSECs with EtOH, followed by silencing P38γ expression. The expression of LYVE-1, CD34, HK2, PKM2, LDHA, and PFKFB3/p-PFKFB3 was assayed by Western blotting, RT-qPCR, and immunofluorescence. Cell viability and migration were evaluated via the MTT method and Transwell assay, respectively. Angiogenesis ability was analyzed through the Matrigel tube formation assay. Levels of lactate, ATP, TNF-α, IL-1β, IL-6, and TGF-β1 were measured via ELISA. Glucose uptake efficiency was assessed by the 2-NBDG uptake assay. The co-localization of LYVE-1 and CD34 was observed via immunofluorescence. PFKFB3 was overexpressed in rescue experiments to verify its role in P38γ-regulated glycolysis.

RESULTS

EtOH induction upregulated P38γ expression in hHSECs. Silencing P38γ enhanced cell viability, promoted the expression of the LSEC differentiation marker LYVE-1, and inhibited the expression of the dedifferentiation marker CD34. Silencing P38γ suppressed EtOH-induced migration of hHSECs, abnormal angiogenesis, inflammation, and fibrosis. Silencing P38γ reduced glucose uptake, lactate production, and ATP levels in cells and downregulated HK2, PKM2, and LDHA. P38γ drove glycolysis by phosphorylating PFKFB3. Overexpression of PFKFB3 reversed the inhibitory effect on glycolysis caused by P38γ silencing.

CONCLUSION

P38γ is a key driver of hHSEC injury in ALD. P38γ reprograms cellular energy metabolism and promotes hHSEC capillarization, inflammation, and fibrosis via the P38γ/PFKFB3 signaling axis.