Paeonol alleviates lipopolysaccharide‑induced hepatocytes injury through alteration of mitochondrial function and NF‑κB translocation

Exploring the anti-inflammatory and immunomodulatory potential of licochalcone B against psoralidin-induced liver injury

ETHNOPHARMACOLOGICAL RELEVANCE

Herb-induced liver injury (HILI) represents an exacerbated inflammatory response, with Psoraleae fructus (PF) and its preparations recently associated with hepatotoxicity. Licorice, historically recognized as a detoxifying herbal remedy, is considered to possess hepatoprotective properties. Our previous research identified bavachin, bakuchiol, and psoralidin (PSO) as potential toxic constituents in PF, while licochalcone B (LCB) and echinatin were identified as bioactive components in licorice. However, evidence regarding the interactions of active compounds in herbs and their underlying mechanisms remains limited.

AIM OF THE STUDY

The objective of this study is to assess the potential mechanisms through which LCB modulates immunological and anti-inflammatory responses to treat PSO-induced liver injury by using human hepatocyte cells (L02) and LPS-primed mice.

METHODS

The ameliorative effects of LCB and echinatin on bavachin, bakuchiol, and PSO-induced liver injury were demonstrated in L02 cells. Subsequently, the efficacy of LCB on PSO-induced idiosyncratic liver injury was further validated in C57BL/6 mice under moderate inflammatory stress induced by LPS priming. The mechanisms were preliminarily explored with an integrated strategy of molecular docking, RT-PCR verification, and untargeted metabolomics.

RESULTS

The study shows that LCB significantly reduced cell injury induced by the three chemicals in PF and provided substantial protection against PSO-induced hepatic damage, as indicated by the levels of ALT, AST, and LDH. LCB normalized liver function and remarkedly alleviated hepatic lesions and inflammation caused by PSO in mice under moderate inflammatory stress. The mRNA profiles of both L02 cells and mice liver tissue revealed that LCB mitigated PSO-induced hepatotoxicity by regulating the gene expression of pro-inflammatory cytokines IL1B and TNF, as well as immunoinflammatory genes PIK3CA, AKT1, NFKB1, and NLRP3. Furthermore, untargeted metabolomics of liver tissue indicated that LCB could reverse the abnormal expression of 11 discriminatory metabolites, with the interrelationship between differential metabolites and target genes primarily clustering in glycerophospholipid metabolism, arachidonic acid metabolism, and phosphatidylinositol signaling system.

CONCLUSION

LCB demonstrated a superior anti-inflammatory and immunomodulatory effect on PSO-induced hepatotoxicity by modulating the inflammatory response and metabolic signaling system. Key interactive targets included phosphatidylcholine, phosphatidic acid, and subunit isoforms of PI3K.

Calycosin inhibits hepatocyte apoptosis in acute liver failure by suppressing the TLR4/NF-κB pathway: An in vitro study

BACKGROUND

Acute liver failure (ALF) is a serious liver disease that is difficult to treat owing to its unclear pathogenesis. This study aimed to investigate the roles and molecular mechanisms of calycosin (CA) in ALF.

METHODS

In this study, the roles and mechanism of CA in ALF were explored using an in vitro lipopolysaccharide (LPS)-induced ALF cell model. Additionally, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide assay was used to assess the effect of CA on the activity of LPS-induced L02 human liver epithelial cells, and flow cytometry was used to detect apoptosis in L02 cells. Expression levels of apoptosis-related genes, Bax and Bcl-2, were measured using reverse transcription-quantitative polymerase chain reaction and Western blot analysis. Expression levels of inflammatory factors in LPS-induced L02 cells were measured using an enzyme-linked immunosorbent assay. Additionally, the effect of CA on ALF was inhibited via transfection of a toll-like receptor 4 (TLR4)-plasmid to elucidate the relationship between CA and TLR4/nuclear factor (NF)-κB signaling pathway in ALF.

RESULTS

CA had no toxic effects on L02 cells, but enhanced the activity of LPS-induced L02 cells in a dose-dependent manner. Apoptosis and inflammatory factor release was increased in ALF, activating the TLR4/NF-κB signaling pathway. However, CA treatment inhibited the apoptosis and release of inflammatory factors. Further mechanistic studies revealed that the upregulation of TLR4 expression reversed the alleviating effects of CA on inflammation and apoptosis in LPS-induced L02 cells.

CONCLUSION

CA alleviates inflammatory damage in LPS-induced L02 cells by inhibiting the TLR4/NF-κB pathway and may be a promising therapeutic agent for ALF treatment.

Chitinase 3 like 1 deficiency ameliorates lipopolysaccharide-induced acute liver injury by inhibition of M2 macrophage polarization

Chitinase 3-like-1 protein (CHI3L1) is involved in various infectious diseases, especially sepsis. Aberrant CHI3L1 expression potentially plays a critical role in chronic inflammation because a considerable number of macrophages are associated with immune/inflammatory diseases. In this study, we examined the effect of CHI3L1 on hepatic sepsis injury using a lipopolysaccharide (LPS)-induced model. LPS-treated CHI3L1 knockout (KO) mice exhibited a higher survival rate than LPS-treated CHI3L1 wild-type (WT) mice. In addition, hepatic injury-related enzyme levels (aspartate transaminase, alanine transaminase, and lactate dehydrogenase) decreased in CHI3L1 KO mice sera, suggesting attenuated LPS-induced septic liver damage in CHI3L1 KO mice. A greater reduction in the mRNA and protein expressions of M2 polarization markers, such as MRC1, ARG1, IL-10, and IL-4, was observed in LPS-induced CHI3L1 KO mice livers than in LPS-induced WT mice livers. Nonetheless, no change in the mRNA and protein expressions of M1 polarization markers, such as INOS, CD86, TNF-α, and IL6, was noted in LPS-induced CHI3L1 KO mice livers compared with those in LPS-induced WT and KO mice. Similar to the in vivo scenario, liver CHI3L1 depletion in LPS-treated HEP3B cells significantly decreased M2 polarization marker protein expression. However, M1 polarization marker protein expression did not differ significantly. These results suggest that CHI3L1 depletion decreases M2 macrophage polarization, and this effect is potentially associated with the alleviation of liver sepsis in CHI3L1 KO mice.

Antioxidant mitoquinone ameliorates EtOH-LPS induced lung injury by inhibiting mitophagy and NLRP3 inflammasome activation

Chronic ethanol abuse is a systemic disorder and a risk factor for acute respiratory distress syndrome (ARDS) and chronic obstructive pulmonary disease (COPD). However, the mechanisms involved are unknown. One explanation is that ethanol produces damaging reactive oxygen species (ROS) and disturbs the balance of mitochondria within the lungs to promote a pro-injury environment. We hypothesized that targeting an antioxidant to the mitochondria would prevent oxidative damage and attenuate EtOH-LPS-induced lung injury. To test this, we investigated the effects of mitochondria-targeted ubiquinone, Mitoquinone (MitoQ) on ethanol-sensitized lung injury induced by LPS. Lung inflammation, ROS, mitochondria function, and mitophagy were assessed. We demonstrated that chronic ethanol feeding sensitized the lung to LPS-induced lung injury with significantly increased reactive oxygen species ROS level and mitochondrial injury as well as lung cellular NLRP3 inflammasome activation. These deleterious effects were attenuated by MitoQ administration in mice. The protective effects of MitoQ are associated with decreased cellular mitophagy and NLRP3 inflammasome activation in vivo and in vitro. Taken together, our results demonstrated that ethanol aggravated LPS-induced lung injury, and antioxidant MitoQ protects from EtOH-LPS-induced lung injury, probably through reducing mitophagy and protecting mitochondria, followed by NLRP3 inflammasome activation. These results will provide the prevention and treatment of ethanol intake effects with new ideas.