Silent information regulator sirtuin 1 ameliorates acute liver failure via the p53/glutathione peroxidase 4/gasdermin D axis

BACKGROUND Acute liver failure(ALF)has a high mortality with widespread hepatocyte death involving ferroptosis and pyroptosis.The silent information regulator sirtuin 1(SIRT1)-mediated deacetylation affects multiple biological processes,including cellular senescence,apoptosis,sugar and lipid metabolism,oxidative stress,and inflammation.AIM To investigate the association between ferroptosis and pyroptosis and the upstream regulatory mechanisms.METHODS This study included 30 patients with ALF and 30 healthy individuals who underwent serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)testing.C57BL/6 mice were also intraperitoneally pretreated with SIRT1,p53,or glutathione peroxidase 4(GPX4)inducers and inhibitors and injected with lipopolysaccharide(LPS)/D-galactosamine(D-GalN)to induce ALF.Gasdermin D(GSDMD)^(-/-)mice were used as an experimental group.Histological changes in liver tissue were monitored by hematoxylin and eosin staining.ALT,AST,glutathione,reactive oxygen species,and iron levels were measured using commercial kits.Ferroptosis-and pyroptosis-related protein and mRNA expression was detected by western blot and quantitative real-time polymerase chain reaction.SIRT1,p53,and GSDMD were assessed by immunofluorescence analysis.RESULTS Serum AST and ALT levels were elevated in patients with ALF.SIRT1,solute carrier family 7a member 11(SLC7A11),and GPX4 protein expression was decreased and acetylated p5,p53,GSDMD,and acyl-CoA synthetase long-chain family member 4(ACSL4)protein levels were elevated in human ALF liver tissue.In the p53 and ferroptosis inhibitor-treated and GSDMD^(-/-)groups,serum interleukin(IL)-1β,tumour necrosis factor alpha,IL-6,IL-2 and C-C motif ligand 2 levels were decreased and hepatic impairment was mitigated.In mice with GSDMD knockout,p53 was reduced,GPX4 was increased,and ferroptotic events(depletion of SLC7A11,elevation of ACSL4,and iron accumulation)were detected.In vitro,knockdown of p53 and overexpression of GPX4 reduced AST and ALT levels,the cytostatic rate,and GSDMD expression,restoring SLC7A11 depletion.Moreover,SIRT1 agonist and overexpression of SIRT1 alleviated acute liver injury and decreased iron deposition compared with results in the model group,accompanied by reduced p53,GSDMD,and ACSL4,and increased SLC7A11 and GPX4.Inactivation of SIRT1 exacerbated ferroptotic and pyroptotic cell death and aggravated liver injury in LPS/D-GalNinduced in vitro and in vivo models.CONCLUSION SIRT1 activation attenuates LPS/D-GalN-induced ferroptosis and pyroptosis by inhibiting the p53/GPX4/GSDMD signaling pathway in ALF.

Sirtuin 1 in regulating the p53/glutathione peroxidase 4/gasdermin D axis in acute liver failure

In this editorial,we comment on the article by Zhou et al.The study reveals the connection between ferroptosis and pyroptosis and the effect of silent information regulator sirtuin 1(SIRT1)activation in acute liver failure(ALF).ALF is characterized by a sudden and severe liver injury resulting in significant hepatocyte damage,often posing a high risk of mortality.The predominant form of hepatic cell death in ALF involves apoptosis,ferroptosis,autophagy,pyroptosis,and necroptosis.Glutathione peroxidase 4(GPX4)inhibition sensitizes the cell to ferroptosis and triggers cell death,while Gasdermin D(GSDMD)is a mediator of pyroptosis.The study showed that ferroptosis and pyroptosis in ALF are regulated by blocking the p53/GPX4/GSDMD pathway,bridging the gap between the two processes.The inhibition of p53 elevates the levels of GPX4,reducing the levels of inflammatory and liver injury markers,ferroptotic events,and GSDMDN protein levels.Reduced p53 expression and increased GPX4 on deletion of GSDMD indicated ferroptosis and pyroptosis interaction.SIRT1 is a NAD-dependent deacetylase,and its activation attenuates liver injury and inflammation,accompanied by reduced ferroptosis and pyroptosis-related proteins in ALF.SIRT1 activation also inhibits the p53/GPX4/GSDMD axis by inducing p53 acetylation,attenuating LPS/D-GalN-induced ALF.

Understanding the molecular crossroads in acute liver failure:A pathway to new therapies

In this editorial we comment on the article published in a recent issue of the World Journal of Gastroenterology.Acute liver failure(ALF)is a critical condition characterized by rapid hepatocellular injury and organ dysfunction,and it often necessitates liver transplant to ensure patient survival.Recent research has eluci-dated the involvement of distinct cell death pathways,namely ferroptosis and pyroptosis,in the pathogenesis of ALF.Ferroptosis is driven by iron-dependent lipid peroxidation,whereas pyroptosis is an inflammatory form of cell death;both pathways contribute to hepatocyte death and exacerbate tissue damage.This comprehensive review explores the interplay between ferroptosis and pyroptosis in ALF,highlighting the role of key regulators such as silent information regulator sirtuin 1.Insights from clinical and preclinical studies provide valuable perspectives on the dysregulation of cell death pathways in ALF and the therapeutic potential of targeting these pathways.Collaboration across multiple disciplines is essential for translating the experimental insights into effective treatments for this life-threatening condition.

Targeting both ferroptosis and pyroptosis may represent potential therapies for acute liver failure

In this editorial,we comment on the article published in the recent issue of the World Journal of Gastroenterology.Acute liver failure(ALF)is a fatal disease that causes uncontrolled massive hepatocyte death and rapid loss of liver function.Ferroptosis and pyroptosis,cell death forms that can be initiated or blocked concurrently,can play significant roles in developing inflammation and various malignancies.However,their roles in ALF remain unclear.The article discovered the positive feedback between ferroptosis and pyroptosis in the progression of ALF,and revealed that the silent information regulator sirtuin 1(SIRT1)inhibits both pathways through p53,dramatically reducing inflammation and protecting hepatocytes.This suggests the potential use of SIRT1 and its downstream molecules as therapeutics for ALF.Thus,we will discuss the role of ferroptosis and pyroptosis in ALF and the crosstalk between these cell death mechanisms.Additionally,we address potential treatments that could alleviate ALF by simultaneously inhibiting both cell death pathways,as well as examples of SIRT1 activators being used as disease treatment strategies,providing new insights into the therapy of ALF.

Novel nervous and multi-system regenerative therapeutic strategies for diabetes mellitus with mTOR

Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin（m TOR） is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1（m TORC1） and m TOR Complex 2（m TORC2） and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase（PI 3-K）,protein kinase B（Akt）,AMP activated protein kinase（AMPK）,silent mating type information regulation 2 homolog 1（Saccharomyces cerevisiae）（SIRT1）,Wnt1 inducible signaling pathway protein 1（WISP1）,and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.