Thymoquinone (TQ) is a main aromatic component of Nigella sativa L. seeds or Agastache rugosa (Fisch. & C.A.Mey.) Kuntze. The protective mechanism of TQ against acute liver injury induced by acetaminophen (APAP), however, remains unclear. We aimed to investigated the hepato-protective mechanism of TQ on the development of APAP-induced acute liver injury. Male kunming mice were pretreated with TQ or N-acetylcysteine (NAC) before a single APAP injection. Human Chang liver cells were incubated with TQ, SP600125 or AICAR in presence of APAP for 24[Formula: see text]h. TQ pretreatment reduced levels of serum aminotransferases and increased hepatic glutathione and glutathione peroxidase activities via inhibiting CYP2E1 expression. TQ inhibited JNK, ERK and P38 phosphorylation induced by APAP. Meanwhile, TQ inhibited PI3K/mTOR signaling activation and activated AMPK phosphorylation. Moreover, TQ prevented APAP-induced hepatocytes apoptosis regulated by Bcl-2 and Bax. Furthermore, TQ inhibited STAT3 phosphorylation on APAP-induced acute liver injury. In addition, TQ significantly inhibited P2X7R protein expression and IL-1[Formula: see text] release. APAP-enhanced JNK phosphorylation and APAP-suppressed AMPK phosphorylation were also observed in Chang liver cells, and these changes were recovered by pretreatment with TQ, SP600125 and AICAR. Our findings suggest that TQ may actively prevent APAP-induced acute liver injury, and the effect may be mediated by JNK and AMPK signaling pathways.

Excessive alcohol drinking and high-fat diets (HFD) promotes steatohepatitis in comorbidity of NAFLD and AFLD. Taxifolin (TAX) is a rich dihydroxyflavone compound found in onions, milk thistle and Douglas fir....

Background and Purpose:Regulating macrophage-hepatocyte crosstalk through P2X7 receptors has led to new pharmacological strategies to reverse alcoholic hepatosteatosis. We investigated how tetrahydroxystilbene glucoside (2354glu), isolated from Polygonum multiflorum, modulates macrophage-hepatocyte crosstalk during alcoholic hepatosteatosis.Experimental Approach: A model of alcoholic hepatosteatosis was established by giving ethanol intragastrically to C57BL/6 mice. HepG2 cells were incubated in conditioned medium from LPS+ATP-activated THP-1 human macrophages with silenced or overexpressed P2X7 receptors. THP-1 macrophages or mouse peritoneal macrophages were pretreated with 2354glu for 1 hr prior to LPS+ATP stimulation.Western blots, RT-PCR and immunohistochemical analysis were used, along with over-expression and silencing of P2X7 receptors.Key Results: Knockdown or overexpression of P2X7 receptors in THP-1 macrophages affected release of mature IL-1β and, subsequently, modulated lipid metabolism in HepG2 cells via the LKB-AMPK pathway. 2354glu ameliorated alcoholic hepatosteatosis in mice by regulating LKB1-AMPK-SREBP1 pathway and its target genes. Suppression of P2X7 receptor activation by 2354glu inhibited IL-1β release and reduced macrophage and neutrophil infiltration. In macrophages stimulated with LPS+ATP, expression of P2X7 receptors, caspase-1 and NF-κB, release of IL-1β, calcium influx and PI uptake were reduced by 2354glu. SIRT1-LKB1-AMPK-SREBP1 axis-mediated lipid accumulation in HepG2 cells was reduced when they were cultured with conditioned media from LPS+ATP-activated THP-1 macrophages pretreated with 2354glu.Abbreviations: 2345glu, tetrahydroxystilbene glucoside, 2,3,5,4 0 -tetrahydroxy-stilbene-2-O-β-D-glucoside; AMPK, AMP-activated protein kinase; LKB1, liver kinase B1; NLRP3, nucleotidebinding oligomerization domain-like receptor protein 3; SIRT1, sirtuin 1; SREBP1, sterol regulatory element-binding protein 1; TLRs, toll like receptors.

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