Carnosic acid suppressed the formation of NETs in alcoholic hepatosteatosis based on P2X7R-NLRP3 axis

Embelin improves alcoholic steatohepatitis in alcohol-associated liver disease via ATF6-mediated P2X7r-NLRP3 signaling pathway

BACKGROUND

Alcohol-associated liver disease (ALD) manifests with impaired lipid metabolism and inflammation within the liver. Embelin (EB), a natural para-benzoquinone compound derived from the Embelia ribes Burm.f. has several pharmacological properties.

OBJECTIVE

This research examines how EB influences the inflammatory milieu of the liver in ALD.

METHODS

In vivo, we created an ALD model by subjecting mice to the Lieber-DeCarli diet for ten days, supplemented by a solitary binge, and subsequent ATF6 silencing. We employed RNA sequencing to analyze the ALD-related signaling pathways. In vitro experiments involved treating AML12 with EB and ethanol, and administering a siRNA-ATF6 to HepG2 cells. We investigated the ATF6 and P2 × 7r promoter interaction through a dual-luciferase assay. Mouse bone marrow-derived macrophages (BMDMs) were also treated with lipopolysaccharide/adenosine triphosphate (LPS/ATP) and EB to produce a conditioned medium.

RESULTS

EB effectively mitigated lipid synthesis and the formation of neutrophil extracellular traps (NETs) during ALD. RNA sequencing revealed significant alterations in the ATF6/NOD-like receptor pathway in alcohol-induced mice. EB up-regulated ATF6 while down-regulating P2 × 7r-NLRP3 and its target genes. shRNA-mediated ATF6 knockdown markedly increased P2 × 7r protein and mRNA levels in mouse livers and exacerbated lipid accumulation. The absence of ATF6 in hepatocytes impaired the inhibitory effect of EB on the P2 × 7r-NLRP3 pathway. It was demonstrated that ATF6 directly binds to the P2 × 7r promoter. Moreover, EB reduced pyroptosis in BMDMs, thereby diminishing the inflammatory response.

CONCLUSIONS

These findings suggest that EB ameliorates alcoholic steatohepatitis (ASH) by modulating the ATF6-P2 × 7r/NLRP3 signaling pathway in ALD. EB might be a prospective therapeutic candidate, and its mechanism would be a new direction or strategy for alcoholic liver disease.

Thiazole isomers as potential ALK5 inhibitors alleviate P2X7R-mediated inflammation during liver fibrosis

Liver fibrosis is a critical precursor to the progression of cirrhosis and liver cancer. However, the development of precision therapies for this condition has been impeded by incompletely elucidated molecular mechanisms. Activin receptor like kinase 5 (ALK5), termed TGF-β type I receptor (TGF-βRI), has been identified as a promising therapeutic target for antifibrotic drug development. In this study, we designed and synthesized two novel thiazole derivatives (J-1155 and J-1156) featuring enantiomeric amino acid moieties to selectively target ALK5 for hepatic fibrosis treatment. Our data demonstrated that both compounds effectively attenuate hepatic fibrosis and associated inflammation through dual inhibition of the TGF-β/Smad signaling pathway and blockade of the P2X7R-NLRP3 inflammasome axis. In comparison, J-1156 demonstrated superior overall therapeutic efficacy to J-1155 in terms of anti-fibrotic efficacy, while J-1155 exhibited superior modulation of Smurf2. Collectively, our observations demonstrate the potential of J-1155 and J-1156 as dual novel therapeutic agents targeting hepatic fibrosis.

Neutrophil extracellular traps (NETs) and NETosis in alcohol-associated diseases: A systematic review

Heavy alcohol consumption is implicated in the alteration of the antimicrobial function of neutrophils, such as phagocytosis, chemotaxis, the formation of neutrophil extracellular traps (NETs), and the occurrence of NETosis. NETosis is an endogenous process of elimination of invading microbes, autoantibodies, and inflammatory elements such as danger-associated molecular patterns (DAMPs) and pathogen-associated patterns (PAMPs). However, both exaggeration and suppression of NETosis modulate normal physiological and metabolic processes by influencing events at the molecular and cellular levels. Recent research shows that binge alcohol consumption induces NETosis, leading to tissue damage and inflammation. Binge alcohol consumption, chronic alcohol intake, and alcohol use disorder (AUD) can affect immunity and often lead to alcohol-associated liver disease (ALD) and/or other organ damage. Alcohol can lead to detrimental consequences in multiple organs, including the brain, liver, pancreas, and gut. Gut-derived microbial substances, such as endotoxins in the circulation, induce systemic inflammation. Sterile danger signals from damaged cells, cytokines, and prostaglandins act as proinflammatory stimuli and are involved in multiple signaling pathways. The alcohol-induced proinflammatory cytokines chemoattract neutrophils, which interact and coordinate with other immune cells to exaggerate or suppress inflammation within the inflammatory milieu, depending on the alcohol effects. Several proteins, including different receptors, play important roles in the activation and formation of NETs as well as the initiation and execution of NETosis. This review article specifically gathers the current information on NETosis, its biological components, and signaling pathways relating to the formation of NETs and the occurrence of NETosis associated with ALD and AUD in multiorgans, specifically in the brain, liver, and gut. We also briefly describe various therapeutic strategies against AUD-associated NETosis in experimental models and human disease states.

Dihydromyricetin regulates the miR-155-5p/SIRT1/VDAC1 pathway to promote liver regeneration and improve alcohol-induced liver injury

BACKGROUND

Alcohol-related liver disease (ALD) has become an increasingly serious global health issue. In recent years, growing evidence has highlighted the restoration of liver regenerative capacity as an effective therapeutic strategy for improving ALD. Previous studies have demonstrated the protective effect of dihydromyricetin (DMY) in alcohol-induced liver injury, but its pharmacological role in ALD-related liver regeneration impairment remains poorly understood.

OBJECTIVE

This study aims to explore the therapeutic potential and molecular mechanisms of DMY in the context of liver regeneration impairment in ALD.

METHODS

The classic Lieber-DeCarli alcohol liquid diet was used to establish an ALD model in vivo. DMY (75 and 150 mg/kg/day) and silybin (200 mg/kg) were administered for 7 weeks to assess the hepatoprotective effects of DMY. First, biochemical markers and liver histopathology were used to evaluate liver inflammation and steatosis in ALD mice. Second, we explored the potential molecular mechanisms by which DMY improves ALD through serum untargeted metabolomics, hepatic transcriptomics, and single-cell sequencing data. Furthermore, in vivo and in vitro experiments, combined with Western blotting, dual-luciferase reporter assays, and immunofluorescence, were conducted to elucidate the protective mechanisms underlying DMY's effects on ALD.

RESULTS

In vivo studies showed that DMY significantly ameliorated ALT/AST abnormalities, liver inflammation, and steatosis in ALD mice. Multi-omics and bioinformatics analyses revealed that DMY may exert its anti-ALD effects by regulating the miR-155-5p/SIRT1/VDAC1 pathway, thereby mitigating cellular senescence. Notably, knockdown of miR-155 provided partial protection against ethanol-induced liver damage. Additionally, clinical ALD samples and in vivo and in vitro experiments further confirmed that excessive alcohol exposure induces the production of miR-155-5p in liver Kupffer cells. miR-155-5p targets and inhibits SIRT1, promoting the expression of mitochondrial VDAC1, leading to mitochondrial DNA leakage, thereby accelerating hepatocyte senescence and inflammation. However, DMY improved the disruption of the miR-155-5p/SIRT1/VDAC1 pathway and hepatocyte senescence, thereby restoring liver regenerative function and exerting anti-ALD effects.

CONCLUSION

In this study, we provide the first evidence that DMY improves liver inflammation and cellular senescence by regulating the miR-155-5p/SIRT1/VDAC1 positive feedback loop, promoting liver regeneration to improve ALD. In summary, our work provides important research evidence and theoretical support for DMY as a promising candidate drug for the prevention and treatment of ALD.

Casting NETs on Psoriasis: The modulation of inflammatory feedback targeting IL-36/IL-36R axis

NETosis happens when neutrophils are activated and neutrophil extracellular traps (NETs) are formed synchronously, which is a hallmark of psoriasis. However, the specific trigger that drives NET formation and the distinct contents and interaction with interleukin-36 receptor (IL-36R) of NETs remain to be further elucidated. This work identified NET formation driven by toll-like receptor (TLR) 3 ligand (especially polyinosinic-polycytidylic acid (Poly(I:C)) were enhanced by purinergic receptor P2X ligand-gated ion channel 7 receptor (P2X7R) ligands (especially adenosine 5'-triphosphate (ATP)). NET formation was accompanied by the secretion of inflammatory cytokines and characterized by IL-1β decoration. NET formation blockade decreased expressions of inflammatory cytokines and chemokines, which consequently improved inflammatory responses. Additionally, imiquimod (IMQ)-induced psoriasiform symptoms including neutrophilic infiltration tended to be time-sensitive. Mouse primary keratinocytes and mice deficient in Il1rl2, which encodes IL-36R, mitigated inflammatory responses and NET formation, thereby delaying the pathophysiology of psoriasis. Together, the findings provided the therapeutic potential for IL-36 targeting NET inhibitors in psoriasis treatment.

Specnuezhenide ameliorates hepatic fibrosis via regulating SIRT6-Mediated inflammatory signaling cascades

ETHNOPHARMACOLOGICAL RELEVANCE

Ligustrum lucidum W.T. Aiton is a traditional Chinese medicine that has long been used with high hepatoprotective therapeutic and condition value. Specnuezhenide (SP), the standard prominent secoiridoid compound of Fructus Ligustri Lucidi may ameliorate hepatic inflammation in chronic liver diseases.

AIM OF THE STUDY

Regulating inflammation through SIRT6-P2X7R axis has caused the emergence of novel molecular mechanism strategies for reversing hepatic fibrosis. This study focused on the mechanism of SP in modulating the liver inflammatory microenvironment in hepatic fibrosis.

MATERIALS AND METHODS

C57BL/6 mice with hepatic fibrosis were stimulated with thioacetamide (TAA) prior to administration of SP. Hepatic stellate cells (HSCs) or normal mouse primary hepatocytes were exposed to transforming growth factor-β (TGF-β) treatment. Meanwhile, normal mouse bone marrow-derived macrophages (BMDMs) were treated with lipopolysaccharide/adenosine triphosphate (LPS/ATP), aiming to obtain the conditioned medium. HSCs and hepatocytes were transfected with SIRT6 knockdown vector (siRNA-SIRT6) to estimate the impact of SP on the SIRT6-P2X7R/NLRP3 signaling pathway.

RESULTS

SP suppressed the HSCs extracellular matrix (ECM) deposition as well as pro-inflammatory cytokine levels induced by the medium of BMDMs or TGF-β. In addition, SP also significantly up-regulated SIRT6, inhibited P2X7R-NLRP3 inflammasome in HSCs and hepatocytes, and functioned as MDL-800 (a SIRT6 agonist). SP reduced the hepatocytes pyroptosis and further prevented the occurrence of inflammatory response in the liver. SP could inhibit the activation of BMDMs and impede IL-1β and IL-18 from entering extracellular regions. Moreover, deficiency of SIRT6 in HSCs or hepatocytes reduced SP's regulation of P2X7R suppression. For TAA-treated mice, SP mitigated histopathological changes, ECM accumulation, EMT process, and NETs formation in hepatic fibrosis.

CONCLUSIONS

Therefore, SP decreased inflammatory response via SIRT6-P2X7R/NLRP3 pathway and suppressed fibrillogenesis. These findings supported SP as the novel candidate to treat hepatic fibrosis.

An integrated network pharmacology approach reveals that Ampelopsis grossedentata improves alcoholic liver disease via TLR4/NF-κB/MLKL pathway

BACKGROUND

Alcohol-related liver damage is the most prevalent chronic liver disease, which creates a heavy public health burden worldwide. The leaves of Ampelopsis grossedentata have been considered a popular tea and traditional herbal medicine in China for more than one thousand years, and possess anti-inflammatory, antioxidative, hepatoprotective, and antiviral activities.

PURPOSE

We explored the protective effects of Ampelopsis grossedentata extract (AGE) against chronic alcohol-induced hepatic injury (alcoholic liver disease, ALD), aiming to elucidate its underlying mechanisms.

METHODS

Firstly, UPLC-Q/TOF-MS analysis and network pharmacology were used to identify the constituents and elucidate the potential mechanisms of AGE against ALD. Secondly, C57BL/6 mice were pair-fed the Lieber-DeCarli diet containing either isocaloric maltodextrin or ethanol, AGE (150 and 300 mg/kg/d) and silymarin (200 mg/kg) were administered to chronic ethanol-fed mice for 7 weeks to evaluate the hepatoprotective effects. Serum biochemical parameters were determined, hepatic and ileum sections were used for histologic examination, and levels of inflammatory cytokines and oxidative stress in the liver were examined. The potential molecular mechanisms of AGE in improving ALD were demonstrated by RNA-seq, Western blotting analysis, and immunofluorescence staining.

RESULTS

Ten main constituents of AGE were identified using UPLC-Q/TOF-MS and 274 potential ALD-related targets were identified. The enriched KEGG pathways included Toll-like receptor signaling pathway, NF-κB signaling pathway, and necroptosis. Moreover, in vivo experimental studies demonstrated that AGE significantly reduced serum aminotransferase levels and improved pathological abnormalities after chronic ethanol intake. Meanwhile, AGE improved ALD in mice by down-regulating oxidative stress and inflammatory cytokines. Furthermore, AGE notably repaired damaged intestinal epithelial barrier and suppressed the production of gut-derived lipopolysaccharide by elevating intestinal tight junction protein expression. Subsequent RNA-seq and experimental validation indicated that AGE inhibited NF-κB nuclear translocation, suppressed IκB-α, RIPK3 and MLKL phosphorylation and alleviated hepatic necroptosis in mice.

CONCLUSION

In this study, we have demonstrated for the first time that AGE protects against alcoholic liver disease by regulating the gut-liver axis and inhibiting the TLR4/NF-κB/MLKL-mediated necroptosis pathway. Therefore, our present work provides important experimental evidence for AGE as a promising candidate for protection against ALD.

Regulation of the Nur77-P2X7r Signaling Pathway by Nodakenin: A Potential Protective Function against Alcoholic Liver Disease

Alcoholic liver disease (ALD) is the main factor that induces liver-related death worldwide and represents a common chronic hepatopathy resulting from binge or chronic alcohol consumption. This work focused on revealing the role and molecular mechanism of nodakenin (NK) in ALD associated with hepatic inflammation and lipid metabolism through the regulation of Nur77-P2X7r signaling. In this study, an ALD model was constructed through chronic feeding of Lieber-DeCarli control solution with or without NK treatment. Ethanol (EtOH) or NK was administered to AML-12 cells, after which Nur77 was silenced. HepG2 cells were exposed to ethanol (EtOH) and subsequently treated with recombinant Nur77 (rNur77). Mouse peritoneal macrophages (MPMs) were treated with lipopolysaccharide/adenosine triphosphate (LPS/ATP) and NK, resulting in the generation of conditioned media. In vivo, histopathological alterations were markedly alleviated by NK, accompanied by reductions in serum triglyceride (TG), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels and the modulation of Lipin-1, SREBP1, and Nur77 levels in comparison to the EtOH-exposed group (p < 0.001). Additionally, NK reduced the production of P2X7r and NLRP3. NK markedly upregulated Nur77, inhibited P2X7r and Lipin-1, and promoted the function of Cytosporone B, a Nur77 agonist (p < 0.001). Moreover, Nur77 deficiency weakened the regulatory effect of NK on P2X7r and Lipin-1 inhibition (p < 0.001). In NK-exposed MPMs, cleaved caspase-1 and mature IL-1β expression decreased following LPS/ATP treatment (p < 0.001). NK also decreased inflammatory-factor production in primary hepatocytes stimulated with MPM supernatant. NK ameliorated ETOH-induced ALD through a reduction in inflammation and lipogenesis factors, which was likely related to Nur77 activation. Hence, NK is a potential therapeutic approach to ALD.

Gut-immunity-joint axis: a new therapeutic target for gouty arthritis

Gouty arthritis (GA) is an inflammatory disease characterized by pain. The primary goal of current treatment strategies during GA flares remains the reduction of inflammation and pain. Research suggests that the gut microbiota and microbial metabolites contribute to the modulation of the inflammatory mechanism associated with GA, particularly through their effect on macrophage polarization. The increasing understanding of the gut-joint axis emphasizes the importance of this interaction. The primary objective of this review is to summarize existing research on the gut-immune-joint axis in GA, aiming to enhance understanding of the intricate processes and pathogenic pathways associated with pain and inflammation in GA, as documented in the published literature. The refined comprehension of the gut-joint axis may potentially contribute to the future development of analgesic drugs targeting gut microbes for GA.

Rosemary: Unrevealing an old aromatic crop as a new source of promising functional food additive-A review

Rosemary (Rosmarinus officinalis L.) is one of the most famous spice plants belonging to the Lamiaceae family as a remarkably beautiful horticultural plant and economically agricultural crop. The essential oil of rosemary has been enthusiastically welcome in the whole world for hundreds of years. Now, it is wildly prevailing as a promising functional food additive for human health. More importantly, due to its significant aroma, food, and nutritional value, rosemary also plays an essential role in the food/feed additive and food packaging industries. Modern industrial development and fundamental scientific research have extensively revealed its unique phytochemical constituents with biologically meaningful activities, which closely related to diverse human health functions. In this review, we provide a comprehensively systematic perspective on rosemary by summarizing the structures of various pharmacological and nutritional components, biologically functional activities and their molecular regulatory networks required in food developments, and the recent advances in their applications in the food industry. Finally, the temporary limitations and future research trends regarding the development of rosemary components are also discussed and prospected. Hence, the review covering the fundamental research advances and developing prospects of rosemary is a desirable demand to facilitate their better understanding, and it will also serve as a reference to provide many insights for the future promotion of the research and development of functional foods related to rosemary.