Necroptosis molecular mechanisms: Recent findings regarding novel necroptosis regulators

Pristimerin ameliorates colitis‑induced intestinal mucosal injury by inhibiting intestinal epithelial necroptosis

Ulcerative colitis (UC) is a non‑specific inflammatory bowel disease characterized by inflammation of the colonic and rectal mucosa and submucosa and has a globally increasing incidence. A compromised intestinal epithelial barrier function has been established as the primary etiological factor in UC, with necroptosis of intestinal epithelial cells exacerbating barrier disruption. Consequently, the inhibition of necroptosis in these cells has the potential to ameliorate colitis severity and preserve intestinal integrity, thereby offering a promising therapeutic approach for UC management. Pristimerin, a naturally occurring pentacyclic triterpenoid derived from Tripterygium wilfordii Hook.f., has been used in the treatment of various diseases. Although pristimerin has been documented to have therapeutic effects on UC, there is a lack of studies exploring its mechanism of action via necroptosis. The present study aimed to elucidate the role of pristimerin in the treatment of UC by examining its inhibitory effects on necroptosis through both in vivo and in vitro experimental approaches. Pristimerin was found to markedly enhance body weight, colon length and intestinal barrier function, while concurrently reducing fecal blood loss in murine models of colitis. Furthermore, both in vivo and in vitro, pristimerin effectively inhibited the phosphorylation of key necroptosis mediators, including receptor‑interacting protein kinase 1, receptor‑interacting protein kinase 3 and mixed lineage kinase domain‑like protein. These findings collectively suggested that the therapeutic effects of pristimerin in UC may be attributed, at least in part, to its ability to suppress necroptosis, thereby improving intestinal barrier integrity.

Circulating RIPK3 level predicts all-cause mortality in patients on maintenance hemodialysis: a 4-year prospective cohort study

BACKGROUND

Maintenance hemodialysis (MHD) is a well-established modality of renal replacement treatment for patients with end-stage renal disease. Currently, receptor-interacting protein kinase-3 (RIPK3) is considered as a key regulator of inflammation. But its association with mortality in MHD patients remains unclear. Thus, the aim of the present study was to observe the predictive value of plasma RIPK3 for all-cause mortality in patients undergoing MHD with a 4-year follow-up.

METHODS

148 patients undergoing MHD treatment during June 2020 were enrolled. The plasma RIPK3 levels were measured via enzyme-linked immunosorbent assay. Patients were followed up for 4 years to record all-cause mortality until June 2024.

RESULTS

During the 4-year follow-up period, the total incidence of all-cause mortality was 34.46% (51 of 148 participants). Compared with the survival group, the non-survival group presented significantly greater age, diabetes prevalence, serum hs-CRP, plasma RIPK3, and lower serum albumin levels. Cox multivariate analysis revealed an independent association between plasma RIPK3 levels and all-cause mortality. The optimal cutoff value to predict all-cause mortality in patients receiving MHD was 251.54 ng/mL with the AUC of 0.7 (95% CI 0.61-0.79). Kaplan-Meier estimates showed a significantly greater overall survival probability for patients with RIPK3 concentrations lower than 251.5 ng/mL than for those with RIPK3 concentrations ≥ 251.5 ng/mL (p < 0.001).

CONCLUSION

Plasma RIPK3 level may serve as an independent predictor for all-cause mortality in MHD patients.

RIPK1: A Promising Target for Intervention Neuroinflammation

Necroptosis is a novel mode of cell death that differs from traditional apoptosis, characterized by distinct molecular mechanisms and physiopathological features. Recent research has increasingly underscored the pivotal role of necroptosis in various neurological diseases, including stroke, Alzheimer's disease and multiple sclerosis. A defining hallmark of these conditions is neuroinflammation, a complex inflammatory response that critically influences neuronal survival. This review provides a comprehensive analysis of the mechanistic underpinnings of necroptosis and its intricate interplay with neuroinflammation, exploring the interrelationship between the two processes and their impact on neurological disorders. In addition, we discuss potential therapeutic strategies that target the intervention of necroptosis and neuroinflammation, offering novel avenues for intervention. By deepening our understanding of these interconnected processes, the development of more effective treatments approaches holds significant promise for improving patient outcomes in neurological disorders.

An Overview of Hexavalent Chromium-Induced Necroptosis, Pyroptosis, and Ferroptosis

Heavy metals are common environmental industrial pollutants. Due to anthropogenic activity, chromium, especially its hexavalent form [Cr(VI)], is a widespread environmental contaminant that poses a threat to human health. In this review paper, we summarize the currently reported molecular mechanisms involved in chromium toxicity with a focus on the induction of pro-inflammatory non-apoptotic cell death pathways such as necroptosis, pyroptosis, and ferroptosis. The review highlights the ability of chromium to induce necroptosis, pyroptosis, and ferroptosis revealing the signaling pathways involved. Cr(VI) can induce RIPK1/RIPK3-dependent necroptosis both in vitro and in vivo. Chromium toxicity is associated with pyroptotic NLRP3 inflammasome/caspase-1/gasdermin D-dependent secretion of IL-1β and IL-18. Furthermore, this review emphasizes the role of redox imbalance and intracellular iron accumulation in Cr(VI)-induced ferroptosis. Of note, the crosstalk between the investigated lethal subroutines in chromium-induced toxicity is primarily mediated by reactive oxygen species (ROS), which are suggested to act as a rheostat determining the cell death pathway in cells exposed to chromium. The current study provides novel insights into the pro-inflammatory effects of chromium, since necroptosis, pyroptosis, and ferroptosis affect inflammation owing to their immunogenic properties linked primarily with damage-associated molecular patterns. Inhibition of these non-apoptotic lethal subroutines can be considered a therapeutic strategy to reduce the toxicity of heavy metals, including chromium.

RIPK3 in necroptosis and cancer

Receptor-interacting protein kinase-3 is essential for the cell death pathway called necroptosis. Necroptosis is activated by the death receptor ligands and pattern recognition receptors of the innate immune system, leading to significant consequences in inflammation and in diseases, particularly cancer. Necroptosis is highly proinflammatory compared with other modes of cell death because cell membrane integrity is lost, resulting in releases of cytokines and damage-associated molecular patterns that potentiate inflammation and activate the immune system. We discuss various ways that necroptosis is triggered along with its potential role in cancer and therapy.

Cynaropicrin Induces Reactive Oxygen Species-Dependent Paraptosis-Like Cell Death in Human Liver Cancer Cells

Cynaropicrin, a sesquiterpene lactone found in artichoke leaves exerts diverse pharmacological effects. This study investigated whether cynaropicrin has a paraptosis-like cell death effect in human hepatocellular carcinoma Hep3B cells in addition to the apoptotic effects reported in several cancer cell lines. Cynaropicrin-induced cytotoxicity and cytoplasmic vacuolation, a key characteristic of paraptosis, were not ameliorated by inhibitors of necroptosis, autophagy, or pan caspase inhibitors in Hep3B cells. Our study showed that cynaropicrin-induced cytotoxicity was accompanied by mitochondrial dysfunction and endoplasmic reticulum stress along with increased cellular calcium ion levels. These effects were significantly mitigated by endoplasmic reticulum stress inhibitor or protein synthesis inhibitor. Moreover, cynaropicrin treatment in Hep3B cells increased reactive oxygen species generation and downregulated apoptosis-linked gene 2-interacting protein X (Alix), a protein that inhibits paraptosis. The addition of the reactive oxygen species scavenger N-acetyl-L-cysteine (NAC) neutralized cynaropicrin-induced changes in Alix expression and endoplasmic reticulum stress marker proteins counteracting endoplasmic reticulum stress and mitochondrial impairment. This demonstrates a close relationship between endoplasmic reticulum stress and reactive oxygen species generation. Additionally, cynaropicrin activated p38 mitogen activated protein kinase and a selective p38 mitogen activated protein kinase blocker alleviated the biological phenomena induced by cynaropicrin. NAC pretreatment showed the best reversal of cynaropicrin induced vacuolation and cellular inactivity. Our findings suggest that cynaropicrin induced oxidative stress in Hep3B cells contributes to paraptotic events including endoplasmic reticulum stress and mitochondrial damage.

S-acylation in apoptotic and non-apoptotic cell death: a central regulator of membrane dynamics and protein function

Protein lipidation is a collection of important post-translational modifications that modulate protein localization and stability. Protein lipidation affects protein function by facilitating interactions with cellular membranes, changing the local environment of protein interactions. Among these modifications, S-acylation has emerged as a key regulator of various cellular processes, including different forms of cell death. In this mini-review, we highlight the role of S-acylation in apoptosis and its emerging contributions to necroptosis and pyroptosis. While traditionally associated with the incorporation of palmitic acid (palmitoylation), recent findings indicate that other fatty acids can also participate in S-acylation, expanding its functional repertoire. In apoptosis, S-acylation influences the localization and function of key regulators such as Bcl-2-associated X protein and other proteins modulating their role in mitochondrial permeabilization and death receptor signaling. Similarly, in necroptosis, S-acylation of mixed lineage kinase domain-like protein (MLKL) with palmitic acid and very long-chain fatty acids enhances membrane binding and membrane permeabilization, contributing to cell death and inflammatory responses. Recent studies also highlight the role of S-acylation in pyroptosis, where S-acylated gasdermin D facilitates membrane localization and pore assembly upon inflammasome activation. Blocking palmitoylation has shown to suppress pyroptosis and cytokine release, reducing inflammatory activity and tissue damage in septic models. Collectively, these findings underscore S-acylation as a shared and important regulatory mechanism across cell death pathways affecting membrane association of key signaling proteins and membrane dynamics, and offer insights into the spatial and temporal control of protein function.

Epigenetic modulation of the NLRP6 inflammasome sensor as a therapeutic modality to reduce necroptosis-driven gastrointestinal mucosal dysfunction in HIV/SIV infection

BACKGROUND

Gastrointestinal (GI) disease/dysfunction persists in people living with HIV (PLWH) receiving suppressive combination anti-retroviral therapy (ART) leading to epithelial barrier breakdown, microbial translocation and systemic inflammation that can drive non-AIDS associated comorbidities. Although epigenetic mechanisms are predicted to drive GI dysfunction, they remain unknown and unaddressed in HIV/SIV infection. The present study investigated genome-wide changes in DNA methylation, and gene expression exclusively in colon epithelial cells (CE) in response to simian immunodeficiency virus infection (SIV) and long-term low-dose delta-9-tetrahydrocannabinol (THC).

METHODS

Using reduced-representation bisulfite sequencing, we characterized DNA methylation changes in colonic epithelium (CE) of uninfected controls (n=5) and SIV-infected rhesus macaques (RMs) administered vehicle (VEH/SIV; n=7) or THC (THC/SIV; n=6). Intact jejunum resection segments (~5cm) were collected from sixteen ART treated SIV-infected RMs [(VEH/SIV/ART; n=8) and (THC/SIV/ART; n=8)] to confirm protein expression data identified in the colon of ART-naïve SIV-infected RMs. Transcriptomics data was used to confirm expression of differentially methylated genes. Protein expression of differentially methylated genes and their downstream targets was assessed using Immunofluorescence followed by HALO quantification.

RESULTS

SIV infection in ART-naïve RMs induced marked hypomethylation throughout promoter-associated CpG islands (paCGIs) in genes related to inflammatory response (NLRP6, cGAS), cellular adhesion (PCDH17, CDH7) and proliferation (WIF1, SFRP1, TERT, and HAND2) in CEs. Moreover, low-dose THC reduced NLRP6 protein expression in CE by hypermethylating the NLRP6 paCGI and blocked polyI:C induced NLRP6 upregulation in vitro. In ART suppressed SIV-infected RMs, significant NLRP6 protein upregulation during acute infection was unaffected by long-term ART administration during chronic infection despite successful plasma and tissue viral suppression. In this group, NLRP6 protein upregulation was associated with significantly increased expression of necroptosis-driving proteins; phosphorylated-RIPK3(Ser199), phosphorylated-MLKL(Thr357/Ser358), and HMGB1. Most strikingly, adding ART to THC-treated SIV-infected RMs effectively reduced NLRP6 and necroptosis-driving protein expression to pre-infection levels.

CONCLUSIONS

We conclude that DNA hypomethylation-assisted NLRP6 upregulation can lead to its constitutively high expression resulting in the activation of necroptosis signaling via the RIPK3/p-MLKL pathway that can eventually drive intestinal epithelial loss/death. From a clinical standpoint, low-dose phytocannabinoids in combination with ART could safely and successfully reduce/reverse persistent GI inflammatory responses via modulating DNA methylation.

The role and intrinsic connection of cellular senescence and cell death in inflammatory bowel disease

Cellular senescence in the intestine can induce cell death, which extends beyond the mere clearance of senescent cells. This phenomenon is prevalent in inflammatory and immune-related diseases, particularly in inflammatory bowel disease (IBD). IBD is characterized by recurrent and chronic intestinal inflammation, with the occurrence and development of the disease being influenced by multiple factors, including genetics, environment, lifestyle, intestinal immunity, and gut microbiota. Chronic intestinal inflammation drives aging of the IBD immune system, reducing its efficiency and impairing the clearance of senescent cells. The disruption of cell death regulation and the interplay between cell death and cellular senescence contribute to disease progression in IBD, with inflammaging and immunosenescence playing the key role in this process. However, the mechanisms underlying the interplay between cell death and cellular senescence in the context of IBD remain unclear. Therefore, this paper comprehensively reviews the impact of cellular death and cellular senescence on intestinal aging in IBD, emphasizing the exploration of their potential interrelationships.

The Role of Post-Translational Modifications in Necroptosis

Necroptosis, a distinct form of regulated necrosis implicated in various human pathologies, is orchestrated through sophisticated signaling pathways. During this process, cells undergoing necroptosis exhibit characteristic necrotic morphology and provoke substantial inflammatory responses. Post-translational modifications (PTMs)-chemical alterations occurring after protein synthesis that critically regulate protein functionality-constitute essential regulatory components within these complex signaling cascades. This intricate crosstalk between necroptotic pathways and PTM networks presents promising therapeutic opportunities. Our comprehensive review systematically analyzes the molecular mechanisms underlying necroptosis, with particular emphasis on the regulatory roles of PTMs in signal transduction. Through systematic evaluation of key modifications including ubiquitination, phosphorylation, glycosylation, methylation, acetylation, disulfide bond formation, caspase cleavage, nitrosylation, and SUMOylation, we examine potential therapeutic applications targeting necroptosis in disease pathogenesis. Furthermore, we synthesize current pharmacological strategies for manipulating PTM-regulated necroptosis, offering novel perspectives on clinical target development and therapeutic intervention.

The interplay between Salmonella and host: Mechanisms and strategies for bacterial survival

Salmonella, an intracellular pathogen, infects both humans and animals, causing diverse diseases such as gastroenteritis and enteric fever. The Salmonella type III secretion system (T3SS), encoded within its pathogenicity islands (SPIs), is critical for bacterial virulence by directly delivering multiple effectors into eukaryotic host cells. Salmonella utilizes these effectors to facilitate its survival and replication within the host through modulating cytoskeletal dynamics, inflammatory responses, the biogenesis of Salmonella-containing vacuole (SCV), and host cell survival. Moreover, these effectors also interfere with immune responses via inhibiting innate immunity or antigen presentation. In this review, we summarize the current progress in the survival strategies employed by Salmonella and the molecular mechanisms underlying its interactions with the host. Understanding the interplay between Salmonella and host can enhance our knowledge of the bacterium's pathogenic processes and provide new insights into how it manipulates host cellular physiological activities to ensure its survival.

Recent advances in the role of gasotransmitters in necroptosis

Necroptosis is a finely regulated programmed cell death process involving complex molecular mechanisms and signal transduction networks. Among them, receptor-interacting protein kinase 1 (RIPK1), receptor-interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein are the key molecules regulating this process. In recent years, gasotransmitters such as nitric oxide, carbon monoxide and hydrogen sulfide have been suggested to play a regulatory role in necroptosis. This paper reviews the evidence that these gasotransmitters are involved in the regulation of necroptosis by influencing the production of reactive oxygen species, regulating the modification of S subunits of RIPK1 and RIPK3, regulating inflammatory mediators, and signal transduction. In addition, this review explores the potential therapeutic applications of these gasotransmitters in pathological conditions such as cardiovascular disease and ischemia-reperfusion injury. Although some studies have revealed the important role of gasotransmitters in necroptosis, the specific mechanism of action is still not fully understood. Future research is needed to further elucidate the molecular mechanisms of gasotransmitters in precisely regulating necroptosis, which will help develop new therapeutic strategies to prevent and treat related diseases.

The Role of Necroptosis, Pyroptosis, and Ferroptosis in Porcine Intestinal Injury and Their Regulation by Nutrients and Bioactive Substances

In the early stages of development, piglets exhibit immature intestinal morphology and function, rendering them susceptible to a range of internal and external stressors, such as viral and bacterial infection, and mycotoxin exposure, which causes intestinal damage. The intestinal damage is characterized by various types of cell death within intestinal epithelium. The traditional cell death types have been categorized as necrosis, apoptosis, and autophagy. However, recent research has identified several forms of novel regulated cell death (RCD) such as necroptosis, pyroptosis, and ferroptosis. A growing body of evidence has underscored the pivotal role of necroptosis, pyroptosis, and ferroptosis in intestinal damage in pigs. Moreover, intervention strategies have been shown to mitigate these 3 RCDs when pigs are exposed to excessive adverse factors. This review aims to elucidate the role of these emerging RCDs in intestinal damage and summarize current understanding of their regulation by nutrients and bioactive substances in pigs. Our goal was to provide future intervention strategies designed to alleviate intestinal damage in pigs.

PLGA/HA sustained-release system loaded with liraglutide for the treatment of diabetic periodontitis through inhibition of necroptosis

Diabetes and periodontitis exhibit a bidirectional relationship, posing significant challenges for the treatment of periodontitis in patients with diabetes. Our previous studies showed that the hypoglycemic agent liraglutide (LIRA), together with glycemic control, had favorable therapeutic effects on diabetic periodontitis (DP), achieving a "two birds with one stone" effect. Therefore, exploration of the topical application of LIRA for treating DP is warranted. In this study, nanoparticles were loaded with LIRA using poly (lactic-co-glycolic acid) (PLGA), and their morphology, particle size, encapsulation efficiency, drug loading, and drug release profiles were characterized. These nanoparticles were further encapsulated with hyaluronic acid (HA) to form a LIRA@PLGA/HA sustained-release system. The cytotoxicity of LIRA@PLGA/HA was analyzed using CCK-8 assays, and its anti-inflammatory and osteogenic effects on periodontitis in diabetic rats were evaluated by histology, ELISA, and micro-CT analysis, while its influence on necroptosis-related factors was assessed using qRT-PCR and Western blotting. The results indicated that LIRA@PLGA (30000 Da) exhibited an encapsulation efficiency of 86.2 %, a drug loading capacity of 4.3 %, and a cumulative release of LIRA reaching approximately 60 % after 8 days, thereby meting the requirement for sustained release. Following 24 h of stimulation with various concentrations (0-20 mg/ml) of LIRA@PLGA/HA, the viability of human periodontal ligament cells (HPDLCs) remained above 85 %. Topical application for four weeks significantly inhibited the expression of the inflammatory factors TNF-α and IL-1β in gingival crevicular fluid and serum, reduced inflammatory cell infiltration in periodontal tissues, and attenuated alveolar bone resorption while improving alveolar bone microstructure, showing therapeutic effects similar to the commercial drug PERIOCLINE® (PERIO). Furthermore, LIRA@PLGA/HA reduced the expression of necroptosis-related factors RIPK1, RIPK3, and MLKL. In conclusion, these results suggest that topical application of LIRA@PLGA/HA is effective for the treatment of DP through inhibition of necroptosis, representing a promising treatment strategy.

The role of hydrogen sulfide in the regulation of necroptosis across various pathological processes

Necroptosis is a programmed cell death form executed by receptor-interacting protein kinase (RIPK) 1, RIPK3 and mixed lineage kinase domain-like protein (MLKL), which assemble into an oligomer called necrosome. Accumulating evidence reveals that necroptosis participates in many types of pathological processes. Hence, clarifying the mechanism of necroptosis in pathological processes is particularly important for the prevention and treatment of various diseases. For over 300 years, hydrogen sulfide (H2S) has been widely known in the scientific community as a toxic and foul-smelling gas. However, after discovering the important physiological and pathological functions of H2S, human understanding of this small molecule changed, believing that H2S is the third gas signaling molecule after carbon monoxide (CO) and nitric oxide (NO). H2S plays an important role in various diseases, but the related mechanisms are not yet fully understood. In recent years, more and more studies have shown that H2S regulation of necroptosis is involved in various pathological processes. Herein, we focus on the recent progress on the role of H2S regulation of necroptosis in different pathological processes and profoundly analyze the related mechanisms.

Sorafenib-induced cardiovascular toxicity: A cause for concern

Sorafenib, a multi-target tyrosine kinase inhibitor, is primarily used to manage hepatocellular carcinoma, advanced renal cell carcinoma, and differentiated thyroid cancer. Although this drug extends patient survival and slows tumor progression, its cardiovascular toxicity substantially impacts of quality of life. Effective the prevention and treatment of the resulting complications are needed. The mechanisms underlying of sorafenib-induced cardiovascular toxicity are complex, and remain incompletely understood despite extensive research. In this review, we discuss the incidence of sorafenib-induced cardiovascular toxicity, including hypertension, thromboembolism, and heart failure in clinical settings. We also summarize current research on the underlying mechanisms, such as ferroptosis, necroptosis, autophagy, mitochondrial damage, and endoplasmic reticulum stress. Additionally, we explore studies regarding the protective effects of various drugs against sorafenib-induced cardiovascular toxicity. This in-depth synthesis of data regarding the clinical manifestations and mechanisms of sorafenib-induced cardiotoxicity provides a valuable scientific foundation for developing therapeutic drugs to combat these adverse effects.

Mechanisms and preventive measures of ALDH2 in ischemia‑reperfusion injury: Ferroptosis as a novel target (Review)

Ischemia‑reperfusion injury (IRI) refers to tissue or organ damage that occurs following a period of inadequate blood supply (ischemia) followed by restoration of blood flow (reperfusion) within a short time frame. This phenomenon is prevalent in clinical conditions such as cardiovascular and cerebrovascular disease, organ transplantation and stroke. Despite its frequency, effective therapeutic strategies to mitigate IRI remain elusive in clinical practice, underscoring the need for a deeper understanding of its molecular mechanisms. Aldehyde dehydrogenase 2 (ALDH2), a key enzyme in alcohol metabolism, serves a role in alleviating oxidative stress and cell damage during IRI by modulating oxidative stress, decreasing apoptosis and inhibiting inflammatory responses. ALDH2 exerts protective effects by detoxifying reactive aldehydes, thereby preventing lipid peroxidation and maintaining cellular homeostasis. Furthermore, ferroptosis, a regulated form of cell death driven by iron accumulation and subsequent lipid peroxidation, is a key process in IRI. However, the precise role of ALDH2 in modulating ferroptosis during IRI remains incompletely understood. Although there is an interaction between ALDH2 activity and ferroptosis, the underlying mechanisms have yet to be clarified. The present review examines the role of ALDH2 and ferroptosis in IRI and the potential regulatory influence of ALDH2 on ferroptosis mechanisms, as well as potential targeting of ALDH2 and ferroptosis for IRI treatment and prevention. By elucidating the complex interplay between ALDH2 and ferroptosis, the present review aims to provide new insights for the development of innovative therapeutic strategies to mitigate ischemic tissue damage and improve clinical outcomes.

Insights into the roles of macrophages in Klebsiella pneumoniae infections: a comprehensive review

Klebsiella pneumoniae (KP) infections represent a significant global health challenge, characterized by severe inflammatory sequelae and escalating antimicrobial resistance. This comprehensive review elucidates the complex interplay between macrophages and KP, encompassing pathogen recognition mechanisms, macrophage activation states, cellular death pathways, and emerging immunotherapeutic strategies. We critically analyze current literature on macrophage pattern recognition receptor engagement with KP-associated molecular patterns. The review examines the spectrum of macrophage responses to KP infection, including classical M1 polarization and the newly described M(Kp) phenotype, alongside metabolic reprogramming events such as glycolytic enhancement and immune responsive gene 1 (IRG1)-itaconate upregulation. We systematically evaluate macrophage fate decisions in response to KP, including autophagy, apoptosis, pyroptosis, and necroptosis. Furthermore, we provide a critical assessment of potential future therapeutic modalities. Given the limitations of current treatment paradigms, elucidating macrophage-KP interactions is imperative. Insights gained from this analysis may inform the development of novel immunomodulatory approaches to augment conventional antimicrobial therapies, potentially transforming the clinical management of KP infections.

Natural products targeting regulated cell deaths for adriamycin-induced cardiotoxicity

Adriamycin (ADR), as an anti-cancer drug in routine clinical application, is utilized to treat various cancers such as ovarian cancer, hematological malignant tumor, and endometrial carcinoma. However, its serious dose-dependent cardiotoxicity extremely limits its clinical application. Currently, there remains a dearth of therapeutic agents to mitigate ADR-induced cardiotoxicity. Extensive research has demonstrated that ADR can simultaneously trigger various regulated cell death (RCD) pathways, such as apoptosis, autophagy, ferroptosis, necroptosis, and pyroptosis. Therefore, drugs targeting these RCD pathways may represent effective strategies for treating ADR-induced cardiotoxicity. Natural products, with their wide availability, low cost, and diverse pharmacological activities, have increasingly gained attention. Various natural products, including polyphenols, flavonoids, terpenoids, and alkaloids, can target the RCD pathways involved in ADR-induced cardiotoxicity. Furthermore, these natural products have exhibited excellent properties in preclinical studies or in vitro experiments. This review summarizes the mechanisms of RCD in ADR-induced cardiotoxicity and systematically reviews the natural products targeting these RCD pathways. Finally, we propose future research directions of natural products in this field.

From death to birth: how osteocyte death promotes osteoclast formation

Bone remodeling is a dynamic and continuous process involving three components: bone formation mediated by osteoblasts, bone resorption mediated by osteoclasts, and bone formation-resorption balancing regulated by osteocytes. Excessive osteocyte death is found in various bone diseases, such as postmenopausal osteoporosis (PMOP), and osteoclasts are found increased and activated at osteocyte death sites. Currently, apart from apoptosis and necrosis as previously established, more forms of cell death are reported, including necroptosis, ferroptosis and pyroptosis. These forms of cell death play important role in the development of inflammatory diseases and bone diseases. Increasing studies have revealed that various forms of osteocyte death promote osteoclast formation via different mechanism, including actively secreting pro-inflammatory and pro-osteoclastogenic cytokines, such as tumor necrosis factor alpha (TNF-α) and receptor activator of nuclear factor-kappa B ligand (RANKL), or passively releasing pro-inflammatory damage associated molecule patterns (DAMPs), such as high mobility group box 1 (HMGB1). This review summarizes the established and potential mechanisms by which various forms of osteocyte death regulate osteoclast formation, aiming to provide better understanding of bone disease development and therapeutic target.

Equal performance of HTK-based and UW-based perfusion solutions in sub-normothermic liver machine perfusion

Machine perfusion (MP) is gaining importance in liver transplantation, the only cure for many end-stage liver diseases. Varieties of different MP protocols are available. Currently, various MP protocols are available, differing not only in perfusion temperature but also in the specific perfusion solution required. We aimed to investigate the performance of an HTK-based perfusate during sub-normothermic MP (SNMP) of discarded human liver grafts compared to that of a UW-based solution. Twenty discarded livers (rejected for transplantation by all centers) were subjected to ex-vivo SNMP at 21°C with either HTK- or UW-based solution for 12 h. Perfusate and tissue samples collected before the start, after 6 h, and at the end of SNMP were analyzed for liver enzymes, along with mRNA expression of perfusate and tissue markers associated with organ damage. Hepatocellular viability was assessed by measuring bile production, monitoring pH stability, and analyzing histological changes in HE stained tissue sections. After propensity score matching 16 livers were analyzed. Overall, no differences between HTK- and UW-based solution were detected, except for an increased MLKL mRNA expression and impaired pH stability during SNMP with HTK-based perfusate. No other investigated parameters of cell injury, inflammation or hepatocellular viability supported this finding. Bile production was higher in the 6 HTK-perfused livers compared to the three UW-perfused livers that produced bile. Overall, these findings suggest that HTK performs comparably to a UW-based solution during 12 h of liver SNMP.

SIRT1 Alleviates Mitochondrial Fission and Necroptosis in Cerebral Ischemia/Reperfusion Injury via SIRT1-RIP1 Signaling Pathway

Programmed cell death, including necroptosis, plays a critical role in the pathogenesis of cerebral ischemia/reperfusion injury (CIRI). Silent information regulator 1 (SIRT1) has been identified as a potential therapeutic target for CIRI, yet its precise role in regulating necroptosis remains controversial. Furthermore, the potential interaction between SIRT1 and receptor-interacting protein kinase 1 (RIP1) in this context is not fully understood. Sanpian Decoction (SPD), a classical traditional herbal formula, was previously shown to enhance SIRT1 expression in our studies. Our findings demonstrated that, both in vivo and in vitro, CIRI was associated with a decrease in SIRT1 levels and phosphorylated dynamin-related protein 1 (p-DRP1) at Ser637, alongside an increase in RIP1 and other necroptosis-related proteins. Co-immunoprecipitation and immunofluorescence analyses revealed a weakened interaction between SIRT1 and RIP1. Furthermore, abnormal mitochondrial fission and dysfunction were mediated through the phosphoglycerate mutase 5-DRP1 pathway. Notably, SPD treatment improved neurological outcomes and reversed these pathological changes by enhancing the SIRT1-RIP1 interaction. In conclusion, this study suggests that SIRT1 is a promising therapeutic target for CIRI, capable of inhibiting necroptosis and mitigating mitochondrial fission via the SIRT1-RIP1 pathway. SPD exhibits therapeutic potential by activating SIRT1, thereby attenuating necroptosis and mitochondrial fission during CIRI.

Mitochondrial alterations and signatures in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer worldwide. Its primary risk factors are chronic liver diseases such as metabolic fatty liver disease, non-alcoholic steatohepatitis, and hepatitis B and C viral infections. These conditions contribute to a specific microenvironment in liver tumors which affects mitochondrial function. Mitochondria are energy producers in cells and are responsible for maintaining normal functions by controlling mitochondrial redox homeostasis, metabolism, bioenergetics, and cell death pathways. HCC involves abnormal mitochondrial functions, such as accumulation of reactive oxygen species, oxidative stress, hypoxia, impairment of the mitochondrial unfolded protein response, irregularities in mitochondrial dynamic fusion/fission mechanisms, and mitophagy. Cell death mechanisms, such as necroptosis, pyroptosis, ferroptosis, and cuproptosis, contribute to hepatocarcinogenesis and play a significant role in chemoresistance. The relationship between mitochondrial dynamics and HCC is thus noteworthy. In this review, we summarize the recent advances in mitochondrial alterations and signatures in HCC and attempt to elucidate its molecular biology. Here, we provide an overview of the mitochondrial processes involved in hepatocarcinogenesis and offer new insights into the molecular pathology of the disease. This may help guide future research focused on improving patient outcomes using innovative therapies.

Cuproptosis: A Copper-Mediated Programmed Cell Death

It has been found that various heavy metals can initiate different types of regulated cell deaths. Among these metals, copper, an essential trace micronutrient that plays a major role in a lot of physiological processes, also can initiate cell death. It can act as a constituent of metalloenzymes, and can act as a mediator for signaling pathways to regulate proliferation and metastasis of tumor. It is also an integral part of some metal-based anticancer drugs. Recent studies have revealed that excessive intracellular copper accumulation leads to the aggregation of mitochondrial lipoylated proteins, causing proteotoxic stress and ultimately resulting in cell death. This newly discovered copper-induced cell death is termed as cuproptosis. In the last few years, a lot of research has been done to understand the mechanism of copper-mediated cell death, and attempts have also been made to identify the relationship between cuproptosis and the development of cancer. In this review, we have provided a comprehensive overview on the significance of copper, its regulation inside the body, the possible mechanism of cuproptosis, and how this cuproptosis can be employed as a therapeutic tool for cancer ablation.

Neuronal Injury after Ischemic Stroke: Mechanisms of Crosstalk Involving Necroptosis

Ischemic stroke is a leading cause of disability and death worldwide, largely due to its increasing incidence associated with an aging population. This condition results from arterial obstruction, significantly affecting patients' quality of life and imposing a substantial economic burden on healthcare systems. While current treatments primarily focus on the rapid restoration of blood flow through thrombolytic therapy or surgical interventions, a limited understanding of neuronal injury mechanisms hampers the development of more effective treatments.This article explores the interplay among various cell death pathways-necroptosis, apoptosis, autophagy, ferroptosis, and pyroptosis-in the context of ischemic stroke to identify novel therapeutic targets. Each mode of cell death displays unique characteristics and roles post-stroke, and the activation of these pathways may vary across different animal models, complicating the translation of therapeutic strategies to clinical settings. Notably, the interaction between apoptosis and necroptosis is highlighted; inhibiting apoptosis might heighten the risk of necroptosis. Therefore, a balanced regulation of these pathways could promote enhanced neuronal survival.Additionally, we introduce PANoptosis, a form of cell death that encompasses pyroptosis, apoptosis, and necroptosis, emphasizing the complexity and potential therapeutic implications of these interactions. In summary, understanding the relationships among these cell death mechanisms in ischemic stroke is vital for developing new neuroprotective agents. Future research should aim for combinatorial interventions targeting multiple pathways to optimize treatment strategies and improve patient outcomes.

Curcuminoids as natural modulators of necroptosis: therapeutic implications

Necroptosis is an emerging form of programmed cell death characterized by necrosis, an inflammatory type of cell death. Necroptosis is primarily initiated by specific mediators that interact with receptor proteins, leading to the activation of protein kinases RIPK1 and RIPK3. These kinases transmit death signals and recruit and phosphorylate mixed lineage kinase domain-like protein (MLKL), which ultimately triggers cell death and necroptosis. Curcuminoids, natural compounds derived from turmeric, have been shown to possess various therapeutic benefits, including neuroprotective, anti-metabolic syndrome, anti-inflammatory, and anti-cancer effects. In this concise overview, we aim to explore the relationship between curcuminoids and the molecular mechanisms of the necroptosis pathway based on recent in vivo and in vitro studies. The available literature indicates that curcuminoids, mainly curcumin, can act as inhibitors of necroptosis in tissue damage scenarios while serving as a necroptosis inducer in cancer cells. Curcuminoids significantly influence key indicators of necroptosis, highlighting their potential to enhance disease treatment. Future studies should focus on further investigating this important component of turmeric to advance therapeutic approaches.

CHMP4C promotes pancreatic cancer progression by inhibiting necroptosis via the RIPK1/RIPK3/MLKL pathway

INTRODUCTION

Pancreatic cancer (PC) cannot currently be completely cured and has a poor prognosis. Necroptosis is a distinct form of regulated cell death that differs from both necrosis and apoptosis. Understanding the role of necroptosis during PC progression would open new avenues for targeted therapy.

OBJECTIVES

The purpose of this study is to examine the impact of necroptosis on the progression of PC and related mechanisms.

METHODS

RNA sequencing was performed to identify necroptosis-related genes that are differentially expressed in PC tissues. The biological functions of CHMP4C and its necroptosis effects were determined in vitro and in vivo. RNA immunoprecipitation, MeRIP-qPCR, Co-immunoprecipitation assays were conducted to evaluate the interaction among CHMP4C, YBX1 and caspase-8 mRNA. Extracellular vesicles were isolated using the differential ultracentrifugation method. The expression of CHMP4C, p-MLKL and CD117 were detected on a PC tissue microarray using multiplex immunofluorescence staining.

RESULTS

CHMP4C was significantly overexpressed in PC cells and tissues. It promoted cell growth and suppressed necroptosis of PC cells in both in vivo and in vitro settings. Mechanistically, CHMP4C interacted with YBX1 to mediate m5C modification of caspase-8 mRNA, resulting in increased caspase-8 expression and inhibition of RIPK1/RIPK3/MLKL pathway phosphorylation. Furthermore, CHMP4C promoted extracellular exocytosis of p-MLKL to further suppress necroptosis. Additionally, PC cells used CHMP4C within extracellular vesicles to recruit and stimulate mast cells (MCs), which in turn promoted PC cell proliferation. In PC tissues, the expression of CHMP4C showed a negative correlation with p-MLKL and a positive association with CD117. High expression levels of CHMP4C in patients were associated with poorer overall survival outcomes.

CONCLUSIONS

CHMP4C promotes PC progression by inhibiting necroptosis, which has potential as a biomarker and therapeutic target in PC.

Elucidating the dual roles of apoptosis and necroptosis in diabetic wound healing: implications for therapeutic intervention

Wound healing is a complex and multistep biological process that involves the cooperation of various cell types. Programmed cell death, including apoptosis and necrotizing apoptosis, plays a crucial role in this process. Apoptosis, a controlled and orderly programmed cell death regulated by genes, helps eliminate unnecessary or abnormal cells and maintain internal environmental stability. It also regulates various cell functions and contributes to the development of many diseases. In wound healing, programmed cell death is essential for removing inflammatory cells and forming scars. On the other hand, necroptosis, another form of programmed cell death, has not been thoroughly investigated regarding its role in wound healing. This review explores the changes and apoptosis of specific cell groups during wound healing after an injury and delves into the potential underlying mechanisms. Furthermore, it briefly discusses the possible mechanisms linking wound inflammation and fibrosis to apoptosis in wound healing. By understanding the relationship between apoptosis and wound healing and investigating the molecular mechanisms involved in apoptosis regulation, new strategies for the clinical treatment of wound healing may be discovered.

Cuproptosis: molecular mechanisms, cancer prognosis, and therapeutic applications

Cuproptosis differs from other forms of cell death, such as apoptosis, necroptosis, and ferroptosis, in its unique molecular mechanisms and signaling pathways. In this review, we delve into the cellular metabolic pathways of copper, highlighting the role of copper in biomolecule synthesis, mitochondrial respiration, and antioxidant defense. Furthermore, we elucidate the relationship between cuproptosis-related genes (CRGs) and cancer prognosis, analyzing their expression patterns across various tumor types and their impact on patient outcomes. Our review also uncovers the potential therapeutic applications of copper chelators, copper ionophores, and copper-based nanomaterials in oncology. In addition, we discuss the emerging role of cuproptosis in remodeling the tumor microenvironment, enhancing immune cell infiltration, and converting "cold tumors" into "hot tumors" that respond better to immunotherapy. In short, this review underscores the pivotal importance of cuproptosis in cancer biology and highlights its translational potential as a novel therapeutic target.

Ferroptosis: A New Pathway in the Interaction between Gut Microbiota and Multiple Sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disorder marked by neuroinflammation, demyelination, and neuronal damage. Recent advancements highlight a novel interaction between iron-dependent cell death, known as ferroptosis, and gut microbiota, which may significantly influences the pathophysiology of MS. Ferroptosis, driven by lipid peroxidation and tightly linked to iron metabolism, is a pivotal contributor to the oxidative stress observed in MS. Concurrently, the gut microbiota, known to affect systemic immunity and neurological health, emerges as an important regulator of iron homeostasis and inflammatory responses, thereby influencing ferroptotic pathways. This review investigates how gut microbiota dysbiosis and ferroptosis impact MS, emphasizing their potential as therapeutic targets. Through an integrated examination of mechanistic pathways and clinical evidence, we discuss how targeting these interactions could lead to novel interventions that not only modulate disease progression but also offer personalized treatment strategies based on gut microbiota profiling. This synthesis aims at deepening insights into the microbial contributions to ferroptosis and their implications in MS, setting the stage for future research and therapeutic exploration.

The Necroptotic Process-related Signature Predicts Immune Infiltration and Drug Sensitivity in Kidney Renal Papillary Cell Carcinoma

BACKGROUND

It remains controversial whether the current subtypes of kidney renal papillary cell carcinoma (KIRP) can be used to predict the prognosis independently.

OBJECTIVE

This observational study aimed to identify a risk signature based on necroptotic process- related genes (NPRGs) in KIRP.

METHODS

In the training cohort, LASSO regression was applied to construct the risk signature from 158 NPRGs, followed by the analysis of Overall Survival (OS) using the Kaplan-Meier method. The signature accuracy was evaluated by the Receiver Operating Characteristic (ROC) curve, which was further validated by the test cohort. Wilcoxon test was used to compare the expressions of immune-related genes, neoantigen genes, and immune infiltration between different risk groups, while the correlation test was performed between NPRGs expressions and drug sensitivity. Gene set enrichment analysis was used to investigate the NPRGs' signature's biological functions.

RESULTS

We finally screened out 4-NPRGs (BIRC3, CAMK2B, PYGM, and TRADD) for constructing the risk signature with the area under the ROC curve (AUC) reaching about 0.8. The risk score could be used as an independent OS predictor. Consistent with the enriched signaling, the NPRGs signature was found to be closely associated with neoantigen, immune cell infiltration, and immune-related functions. Based on NPRGs expressions, we also predicted multiple drugs potentially sensitive or resistant to treatment.

CONCLUSION

The novel 4-NPRGs risk signature can predict the prognosis, immune infiltration, and therapeutic sensitivity of KIRP.

Unraveling the role of RIPKs in diabetic kidney disease and its therapeutic perspectives

Nephropathy is the microvascular complication of diabetes mellitus and is the leading cause of chronic kidney disease. This review discusses the implications of receptor-interacting protein kinase (RIPK) family members and their regulation of inflammation and cell death pathways in the initiation and progression of diabetic kidney disease. Hyperglycemia leads to reactive oxygen species (ROS) generation and RIPK1 overexpression, the first regulator of necroptosis. Further, RIPK1 can form complex I to promote nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) pathway activation or complex II to cause programmed cell death in the kidneys. The rise in RIPK1 level upon ROS generation declines the apoptosis regulators' level while the necroptosis regulators' level is boosted. Necroptosis is a programmed or controlled necrosis-type cell death pathway executed by RIPK1, RIPK3, and mixed lineage kinase domain-like (MLKL) proteins, and recent research suggests its importance in diabetic nephropathy. In necroptosis, RIPK1 and RIPK3 interrelate with their RIP homotypic interaction motif (RHIM) domains and cause the recruitment of MLKL. Next, MLKL gets oligomerized, migrate towards the plasma membrane, and causes its rupture. We emphasized different research studies on drugs highlighting the nephroprotective effects via regulating the RIPKs. We hope that the conclusions of this review may provide new strategies for diabetic kidney disease treatment and promising targets for drug development based on necroptosis.

Regulated Cell Death of Alveolar Macrophages in Acute Lung Inflammation: Current Knowledge and Perspectives

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a common and serious clinical lung disease characterized by extensive alveolar damage and inflammation leading to impaired gas exchange. Alveolar macrophages (AMs) maintain homeostatic properties and immune defenses in lung tissues. Several studies have reported that AMs are involved in and regulate ALI/ARDS onset and progression via different regulated cell death (RCD) programs, such as pyroptosis, apoptosis, autophagic cell death, and necroptosis. Notably, the effects of RCD in AMs in disease are complex and variable depending on the environment and stimuli. In this review, we provide a comprehensive perspective on how regulated AMs death impacts on ALI/ARDS and assess its potential in new therapeutic development. Additionally, we describe the crosstalk between different RCD types in ALI, and provide new perspectives for the treatment of ALI/ARDS and other severe lung diseases.

A20 negatively regulates necroptosis-induced microglia/macrophages polarization and mediates cerebral ischemic tolerance via inhibiting the ubiquitination of RIP3

Neuronal necroptosis appears to be suppressed by the deubiquitinating enzyme A20 and is capable to regulate the polarization of microglia/macrophages after cerebral ischemia. We have demonstrated that hypoxic preconditioning (HPC) can alleviate receptor interacting protein 3 (RIP3)-induced necroptosis in CA1 after transient global cerebral ischemia (tGCI). However, it is still unclear whether HPC serves to regulate the phenotypic polarization of microglia/macrophages after cerebral ischemia by mitigating neuronal necroptosis. We hence aim to elucidate the underlying mechanism(s) by which the ubiquitination of RIP3-dependent necroptosis regulated by A20 affects microglia/macrophages phenotype after cerebral ischemic tolerance. We found that microglia/macrophages in CA1 of rats underwent M1 and M2 phenotypic polarization in response to tGCI. Notably, the treatment with HPC, as well as inhibitors of necroptosis, including Nec-1 and mixed lineage kinase domain-like (MLKL) siRNA, attenuated neuroinflammation associated with M1 polarization of microglia/macrophages induced by tGCI. Mechanistically, HPC was revealed to upregulate A20 and in turn enhance the interaction between A20 and RIP3, thereby reducing K63-linked polyubiquitination of RIP3 in CA1 after tGCI. Consequently, RIP3-dependent necroptosis and the M1 polarization of microglia/macrophages were blocked either by HPC or via overexpression of A20 in neurons, which ultimately mitigated cerebral injury in CA1 after tGCI. These data support that A20 serves as a crucial mediator of microglia/macrophages polarization by suppressing neuronal necroptosis in a RIP3 ubiquitination-dependent manner after tGCI. Also, a novel mechanism by which HPC functions in cerebral ischemic tolerance is elucidated.

A systematic review of associations between the environment, DNA methylation, and cognition

The increasing prevalence of neurodegenerative diseases poses a significant public health challenge, prompting a growing focus on addressing modifiable risk factors of disease (e.g. physical inactivity, mental illness, and air pollution). The environment is a significant contributor of risk factors which are known to impact the brain and contribute to disease risk (e.g. air pollution, noise pollution, green and blue spaces). Epigenetics can offer insights into how various environmental exposures impact the body to contribute to cognitive outcomes. In this systematic review, we examined studies which have associated an environmental exposure to a type of epigenetic modification, DNA methylation, and a cognitive outcome. We searched four databases with keywords "environmental exposures," "epigenetics," and "cognition." We yielded 6886 studies that we screened by title/abstract followed by full text. We included 14 studies which focused on four categories of environmental exposure: air pollution (n = 3), proximity to roads (n = 1), heavy metals (n = 6), and pesticides (n = 4). Overall, n = 10/14 studies provided evidence that DNA methylation is statistically significant in the association between the environment and a cognitive outcome. Furthermore, we identified that n = 5/14 studies performed a type of biological pathway analysis to determine the presence of biological pathways between their environmental exposure and cognitive outcome. Our findings underscore the need for methodological improvements and considerations in future studies, including investigation of other environmental exposures considering tissue-specificity of methylation profiles and stratifying analysis by sex, ethnicity and socioeconomic determinants of disease. This review demonstrates that further investigation is warranted, the findings of which may be of use in the development of preventative measures and risk management strategies for neurodegenerative disease.

Integrating necroptosis into pan-cancer immunotherapy: a new era of personalized treatment

Introduction

Necroptosis has emerged as a promising biomarker for predicting immunotherapy responses across various cancer types. Its role in modulating immune activation and therapeutic outcomes offers potential for precision oncology.

Methods

A comprehensive pan-cancer analysis was performed using bulk RNA sequencing data to develop a necroptosis-related gene signature, termed Necroptosis.Sig. Multi-omics approaches were employed to identify critical pathways and key regulators of necroptosis, including HMGB1. Functional validation experiments were conducted in A549 lung cancer cells to evaluate the effects of HMGB1 knockdown on tumor proliferation and malignancy.

Results

The Necroptosis.Sig gene signature effectively predicted responses to immune checkpoint inhibitors (ICIs). Multi-omics analyses highlighted HMGB1 as a key modulator of necroptosis, with potential to enhance immune activation and therapeutic efficacy. Functional experiments demonstrated that HMGB1 knockdown significantly suppressed tumor proliferation and malignancy, reinforcing the therapeutic potential of targeting necroptosis.

Discussion

These findings underscore the utility of necroptosis as a biomarker to guide personalized immunotherapy strategies. By advancing precision oncology, necroptosis provides a novel avenue for improving cancer treatment outcomes.

Metabolomics combined with network pharmacology reveals the protective effect of astragaloside IV on alcoholic liver disease

BACKGROUND

Alcoholic liver disease (ALD) is a significant contributor to liver damage. However, the clinical options for the treatment of ALD are limited. Astragaloside IV (AST-IV) is a saponin isolated from Astragalus membranaceus (AM). This study aimed to explore the underlying mechanisms of action of AST-IV in ALD by integrating metabolomics and network pharmacology.

METHODS

Sprague-Dawley (SD) rats were used to establish a rat model of ALD. AST-IV and polyene phosphatidyl choline (PPC; a positive control drug) were administered to rats with ALD for 4 weeks. We measured the body weight, liver index, ALT, AST, TC, TG, inflammatory markers (IL-1β, IL-6, and TNF-α), and oxidative stress markers (SOD, MDA) and used H&E and ORO staining to evaluate the hepatoprotective effect of both AST-IV and PPC on ALD. Subsequently, we performed untargeted metabolomics to predict the influence of AST-IV on lipid metabolism in rats with ALD. We then used a network pharmacology approach to identify the core targets through which AST-IV corrected lipid metabolism disorders and validated these targets through molecular docking, qRT-PCR and western blot analyses. Finally, we calculated the relationships between ALD-related biochemical markers, differential liver metabolites, and core targets using Spearman's correlation analysis.

RESULTS

AST-IV improved pathological damage and reduced lipid accumulation in the hepatocytes of rats with ALD. Furthermore, AST-IV inhibited oxidative stress and inflammatory responses in rats with ALD. The metabolomic results showed that AST-IV corrected hepatic lipid metabolism disorders by targeting linoleic acid, necrosis, sphingolipid, and glycerophospholipid metabolism. The Network pharmacology analysis revealed that the core targets of AST-IV exerting the above effects were p-RIPK3, p-MLKL, CYP1A2, CYP2C19, PPARα, PCSK9. Spearman's correlation analysis showed a strong correlation between ALD-related serum biochemical indices, core targets, and liver differential metabolites.

CONCLUSION

AST-IV corrects the metabolic disorders of linoleic acid, sphingolipid, and glycerophospholipid, and alleviates necrosis in rats with ALD through the core targets p-RIPK3, p-MLKL, CYP1A2, CYP2C19, PPARα, and PCSK9. This study is the first to reveal the mechanism of ALD protection through AST-IV from the perspective of metabolomics and network pharmacology. Therefore, a novel target has been identified to exert protection against ALD. This study provides a reference for ALD treatment.

LGR6 protects against myocardial ischemia-reperfusion injury via suppressing necroptosis

Regulated necrosis (necroptosis) and apoptosis are important biological features of ischemia-reperfusion (I/R) injury. However, the molecular mechanisms underlying myocardial necroptosis remain elusive. Leucine rich repeat containing G protein-coupled receptor 6 (LGR6) has been reported to play important roles in various cardiovascular disease. In this study, we aimed to determine whether LGR6 suppresses I/R-induced myocardial necroptosis and the underlying molecular mechanisms. We generated LGR6 knockout mice and used ligation of left anterior descending coronary artery to produce an in vivo I/R model. The effects of LGR6 and its downstream molecules were subsequently identified using RNA sequencing and CHIP assays. We observed significantly downregulated LGR6 expression in hearts post myocardial I/R and cardiomyocytes post hypoxia and reoxygenation (HR). LGR6 deficiency promoted and LGR6 overexpression inhibited necroptosis and acute myocardial injury after I/R. Mechanistically, in vivo and in vitro experiments suggest that LGR6 regulates the expression of STAT2 and ZBP1 by activating the Wnt signaling pathway, thereby inhibiting cardiomyocyte necroptosis after HR. Inhibiting STAT2 and ZBP1 effectively alleviated the aggravating effect of LGR6 deficiency on myocardial necroptosis after I/R. Furthermore, activating LGR6 with RSPO3 also effectively protected mice from acute myocardial I/R injury. Our findings reveal that RSPO3-LGR6 axis downregulates the expression of STAT2 and ZBP1 through the Wnt signaling pathway, thereby inhibiting I/R-induced myocardial injury and necroptosis. Targeting the RSPO3-LGR6 axis may be a potential therapeutic strategy to treat myocardial I/R injury.

Prenatal exposure to di-n-butyl phthalate promotes RIPK1-regulated necroptosis of uroepithelial cells and induces hypospadias through the epithelial-mesenchymal transition process in newborn male rats

Maternal exposure to di-n-butyl phthalate (DBP) has been linked to the induction of hypospadias; however, the underlying mechanism remains unclear. Necroptosis is reported to be implicated in developmental malformations. This study aimed to investigate the underlying mechanism of necroptosis in the development of hypospadias. DBP was dissolved in corn oil, and pregnant rats were administered a precisely measured dose of DBP (750 mg/kg/day) via gastric intubation from gestation day 14-18. Control rats received only corn oil. The day of birth was considered postnatal day (PND) 1. Male hypospadias rats were identified on PND 7. Genital tubercle tissues were collected and stored at -80°C for subsequent PCR analysis, cryopreserved in liquid nitrogen for western blot, or fixed in formalin for immunohistochemistry (IHC) staining. IHC staining and western blot analysis revealed increased expression of RIPK1 and necroptosis markers in genital tubercle (GT) tissue compared to the control group. Additionally, higher levels of EMT and impaired androgen receptor expression were observed in GT tissue. Exposure to increased DBP concentrations in rat primary uroepithelial cells (PUCs) led to elevated ROS production. Necroptosis markers and EMT expression levels were upregulated in PUCs following DBP incubation. Notably, treatment with DBP combined with necrostatin-1, a necroptosis inhibitor, reduced the expression of EMT markers and ROS production compared to DBP treatment alone. In vitro studies further revealed that DBP-induced necroptosis promoted the degradation of E-cadherin through the ubiquitin-proteasome pathway in PUCs. Our findings suggest that maternal exposure to DBP promotes necroptosis in uroepithelial cells by elevating ROS level and EMT status. Thus, necroptosis may play an essential role in the development of hypospadias.

Triggering immunogenic death of cancer cells by nanoparticles overcomes immunotherapy resistance

Immunotherapy resistance poses a significant challenge in oncology, necessitating novel strategies to enhance the therapeutic efficacy. Immunogenic cell death (ICD), including necroptosis, pyroptosis and ferroptosis, triggers the release of tumor-associated antigens and numerous bioactive molecules. This release can potentiate a host immune response, thereby overcoming resistance to immunotherapy. Nanoparticles (NPs) with their biocompatible and immunomodulatory properties, are emerging as promising vehicles for the delivery of ICD-inducing agents and immune-stimulatory adjuvants to enhance immune cells tumoral infiltration and augment immunotherapy efficacy. This review explores the mechanisms underlying immunotherapy resistance, and offers an in-depth examination of ICD, including its principles and diverse modalities of cell death that contribute to it. We also provide a thorough overview of how NPs are being utilized to trigger ICD and bolster antitumor immunity. Lastly, we highlight the potential of NPs in combination with immunotherapy to revolutionize cancer treatment.

Necroptosis-based glioblastoma prognostic subtypes: implications for TME remodeling and therapy response

BACKGROUND

Glioblastoma (GBM) is an aggressive primary brain tumor with a high recurrence rate and poor prognosis. Necroptosis, a pathological hallmark of GBM, is poorly understood in terms of its role in prognosis, tumor microenvironment (TME) alteration, and immunotherapy.

METHODS & RESULTS

We assessed the expression of 55 necroptosis-related genes in GBM and normal brain tissues. We identified necroptosis-stratified clusters using Uni-Cox and Least Absolute Shrinkage and Selection Operator (LASSO) regression to establish the 10-gene Glioblastoma Necroptosis Index (GNI). GNI demonstrated significant prognostic efficacy in the TCGA dataset (n = 160) and internal validation dataset (n = 345) and in external validation cohorts (n = 591). The GNI-high subgroup displayed a mesenchymal phenotype, lacking the IDH1 mutation, and MGMT methylation. This subgroup was characterized by significant enrichment in inflammatory and humoral immune pathways with prominent cell adhesion molecules (CD44 and ICAM1), inflammatory cytokines (TGFB1, IL1B, and IL10), and chemokines (CX3CL1, CXCL9, and CCL5). The TME in this subgroup showed elevated infiltration of M0 macrophages, neutrophils, mast cells, and regulatory T cells. GNI-related genes appeared to limit macrophage polarization, as confirmed by immunohistochemistry and flow cytometry. The top 30% high-risk score subset exhibited increased CD8 T cell infiltration and enhanced cytolytic activity. GNI showed promise in predicting responses to immunotherapy and targeted treatment.

CONCLUSIONS

Our study highlights the role of necroptosis-related genes in glioblastoma (GBM) and their effects on the tumor microenvironment and patient prognosis. TheGNI demonstrates potential as a prognostic marker and provides insights into immune characteristics and treatment responsiveness.

A new strategy for the treatment of intracerebral hemorrhage: Ferroptosis

Intracerebral hemorrhage, is a cerebrovascular disease with high morbidity, mortality, and disability. Due to the lack of effective clinical treatments, the development of new drugs to treat intracerebral hemorrhage is necessary. In recent years, ferroptosis has been found to play an important role in the pathophysiological process of intracerebral hemorrhage, which can be treated by inhibiting ferroptosis and thus intracerebral hemorrhage. This article aims to explain the mechanism of ferroptosis and its relationship to intracerebral hemorrhage. In the meantime, it briefly discusses the molecules identified to alleviate intracerebral hemorrhage by inhibiting ferroptosis, along with other clinical agents that are expected to treat intracerebral hemorrhage through this mechanism. In addition, a brief overview of the morphological alterations of different forms of cell death and their role in ICH is provided. Finally, the challenges that may arise in translating ferroptosis inhibitors from basic research to clinical use are presented. This article serves as a reference and provides insights to aid in the treatment of intracerebral hemorrhage in the clinic.

Autophagy in oral cancer: Promises and challenges (Review)

Autophagy captures damaged or dysfunctional proteins and organelles through the lysosomal pathway to achieve proper cellular homeostasis. Autophagy possesses distinct characteristics and is given recognized functions in numerous physiological and pathological conditions, such as cancer. Early stage cancer development can be stopped by autophagy. After tumor cells have successfully undergone transformation and progressed to a late stage, the autophagy-mediated system of dynamic degradation and recycling will support cancer cell growth and adaptation to various cellular stress responses while preserving energy homeostasis. In the present study, the dual function that autophagy plays in various oral cancer development contexts and stages, the existing arguments for and against autophagy, and the ways in which autophagy contributes to oral cancer modifications, such as carcinogenesis, drug resistance, invasion, metastasis and self-proliferation, are reviewed. Special attention is paid to the mechanisms and functions of autophagy in oral cancer processes, and the most recent findings on the application of certain conventional drugs or natural compounds as novel agents that modulate autophagy in oral cancer are discussed. Overall, further research is needed to determine the validity and reliability of autophagy promotion and inhibition while maximizing the difficult challenge of increasing cancer suppression to improve clinical outcomes.

Necroptosis and autophagy in cisplatinum-triggered nephrotoxicity: Novel insights regarding their prognostic and diagnostic potential

Necroptosis is an innovative class of programmed autophagy (Atg) and necrosis; considered as a type of homeostatic housekeeping machinery that have observed an escalating concern due to its power in alleviating Cisplatinum-induced nephrotoxicity. This article elucidated in details the prospective role of both autophagy and necroptosis on Cisplatinum-triggered nephrotoxicity and investigating more potent therapy via lactoferrin and Ti-NPS conjugation. Cisplatinum is a commonly used chemotherapeutic drug; one of the limiting adverse actions of cisplatinum is renal toxicity. Upon cisplatinum administration, autophagy is highly stimulated in the kidney to shield against nephrotoxicity. Atg is a lysosomal degradation process which discards detorirated proteins to retain cell homeostasis. This article summarizes necroptosis progress in reconizing cisplatinum nephrotoxicity and debates how this progress can help in discovering more potent therapy via lactoferrin and Ti-NPS conjugation via monitoring autophagy and apoptotic biomarkers X-box-binding protein 1 (XBP), C/EBP homologous protein (CHOP), hypoxanthine phosphoribosyltransferase-1 (HPRT), FKBP prolyl isomerase 1B (FKBP), Cellular myelocytomatosis oncogene (C-myc), tumor suppressor gene (P53) and tumor necrosis factor (TNF-α). Cisplatinum nephrotoxicity was conducted in rat model via an oral dose of (2 mg/kg BW) for one month furthermore a comparative study was conducted among TiNPs-loaded Cisplatinum and Lactoferrin loaded Cisplatinum. Loaded drug delivery system counteracted Cisplatinum triggered nephrotoxicity via controlling autophagy and apoptotic XBP, CHOP, HPRT, FKBP, C-myc, P53 and TNF-α signaling pathway.

Navigating the complexities of cell death: Insights into accidental and programmed cell death

Cell death is a critical biological phenomenon that can be categorized into accidental cell death (ACD) and programmed cell death (PCD), each exhibiting distinct signaling, mechanistic and morphological characteristics. This paper provides a comprehensive overview of seven types of ACD, including coagulative, liquefactive, caseous, fat, fibrinoid, gangrenous and secondary necrosis, discussing their pathological implications in conditions such as ischemia and inflammation. Additionally, we review eighteen forms of PCD, encompassing autophagy, apoptosis, necroptosis, pyroptosis, paraptosis, ferroptosis, anoikis, entosis, NETosis, eryptosis, parthanatos, mitoptosis, and newly recognized types such as methuosis, autosis, alkaliptosis, oxeiptosis, cuprotosis and erebosis. The implications of these cell death modalities for cellular processes, development, and disease-particularly in the context of neoplastic and neurodegenerative disorders-are also covered. Furthermore, we explore the crosstalk between various forms of PCD, emphasizing how apoptotic mechanisms can influence pathways like necroptosis and pyroptosis. Understanding this interplay is crucial for elucidating cellular responses to stress, as well as for its potential relevance in clinical applications and therapeutic strategies. Future research should focus on clarifying the molecular mechanisms that govern different forms of PCD and their interactions.

Epigenetic modulation of NLRP6 inflammasome sensor as a therapeutic modality to reduce necroptosis-driven gastrointestinal mucosal dysfunction in HIV/SIV infection

The epigenetic mechanisms driving persistent gastrointestinal mucosal dysfunction in HIV/SIV infection is an understudied topic. Using reduced-representation bisulfite sequencing, we identified HIV/SIV infection in combination anti-retroviral therapy (cART)-naive rhesus macaques (RMs) to induce marked hypomethylation throughout promoter-associated CpG islands (paCGIs) in genes related to inflammatory response ( NLRP6, cGAS ), cellular adhesion and proliferation in colonic epithelial cells (CEs). Moreover, low-dose delta-9-tetrahydrocannabinol (THC) administration reduced NLRP6 protein expression in CE by hypermethylating the NLRP6 paCGI and blocked polyI:C induced NLRP6 upregulation in vitro. In cART suppressed SIV-infected RMs, NLRP6 protein upregulation associated with significantly increased expression of necroptosis-driving proteins; phosphorylated-RIPK3(Ser199), phosphorylated-MLKL(Thr357/Ser358), and HMGB1. Most strikingly, supplementing cART with THC effectively reduced NLRP6 and necroptosis-driving protein expression to pre-infection levels. These findings for the first time demonstrate that NLRP6 upregulation and ensuing activation of necroptosis promote HIV/SIV-induced gastrointestinal mucosal dysfunction and that epigenetic modulation using phytocannabinoids represents a feasible therapeutic modality for alleviating HIV/SIV-induced gastrointestinal inflammation and associated comorbidities.

An intracellular bacterial pathogen triggers RIG-I/MDA5-dependent necroptosis

RIG-I and MDA5 are members of RIG-I-like receptors (RLRs) that detect viral RNA within the cytoplasm and subsequently initiate antiviral immune responses. Necroptosis is a form of programmed cell death (PCD) executed by mixed lineage kinase domain-like (MLKL), which, upon phosphorylation by receptor-interacting protein kinase 3 (RIPK3), causes necrotic cell death. To date, no link between RLRs and necroptosis has been observed during bacterial infection. Edwardsiella tarda is a zoonotic bacterial pathogen that can thrive in host macrophages. In a previous study, we identified RIG-I and MDA5 as two hub factors of RAW264.7 cells responsive to E. tarda infection. The present study aimed to determine the specific form of cell death triggered by E. tarda and explore the association between RIG-I/MDA5 and PCD in the context of bacterial infection. Our results showed that E. tarda infection induced RIPK3-MLKL-mediated necroptosis, rather than pyroptosis or apoptosis, in RAW264.7 cells. Meanwhile, E. tarda promoted RIG-I/MDA5 production and activated the RIG-I/MDA5 pathways that led to IRF3 phosphorylation, IFN-β secretion, and interferon-stimulated gene (ISG) and cytokine expression. Both RIG-I and MDA5 were essential for E. tarda-triggered necroptosis and required for effective inhibition of intracellular bacterial replication. Furthermore, the regulatory effect of RIG-I/MDA5 on necroptosis was not affected by type I IFN or TNF-α signaling blockage. Together these results revealed that necroptosis could be triggered by intracellular bacterial infection through the RIG-I/MDA5 pathways, and that there existed intricate interplays between PCD and RLRs induced by bacterial pathogen.

Exposure to perfluorodecanoic acid impairs follicular development via inducing granulosa cell necroptosis

Per- and polyfluoroalkyl substances (PFAS) have attracted significant attention due to their environmental toxicity. However, the detrimental impact of PFAS on the development of the female reproductive system remains controversial. In this study, we investigated the effects of three specific PFAS compounds perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA) on ovarian development. Among these compounds, PFDA demonstrated the most pronounced cytotoxic effect on ovarian granulosa cells. The results showed that a 200 μM concentration of PFDA induced cell apoptosis via the intrinsic pathway by elevating reactive oxygen species (ROS) levels and activating Caspase-9 and Caspase-3. Furthermore, 200 μM PFDA triggered necroptosis, a form of regulated cell death (RCD), through the receptor-interacting serine/threonine kinase 1 (RIPK1), receptor interacting protein kinase 3 (RIPK3), and mixed-lineage kinase domain-like protein (MLKL) axis, mediated by inhibition of the canonical apoptosis proteolytic enzyme Caspase-8. In vivo experiments confirmed that mice exposed to PFDA displayed a significantly reduced ovarian index compared to the control group, accompanied by evident follicular atresia. Ovarian tissues from the PFDA-exposed group showed upregulated necroptosis markers, which were effectively mitigated by inhibiting the phosphorylation of RIPK1 at Ser166. Importantly, this study provides the first evidence that PFDA disrupts ovarian development through a novel mechanism involving the RIPK1-mediated necroptosis pathway, alongside the detection of the intrinsic apoptosis pathway. This greatly expands our insight into the effects of PFDA on cell death. This finding highlights the potential public health hazards associated with PFDA exposure and emphasizes the need for further research to fully understand its broader implications.

Cuproptosis, ferroptosis and PANoptosis in tumor immune microenvironment remodeling and immunotherapy: culprits or new hope

Normal life requires cell division to produce new cells, but cell death is necessary to maintain balance. Dysregulation of cell death can lead to the survival and proliferation of abnormal cells, promoting tumor development. Unlike apoptosis, necrosis, and autophagy, the newly recognized forms of regulated cell death (RCD) cuproptosis, ferroptosis, and PANoptosis provide novel therapeutic strategies for tumor treatment. Increasing research indicates that the death of tumor and immune cells mediated by these newly discovered forms of cell death can regulate the tumor microenvironment (TME) and influence the effectiveness of tumor immunotherapy. This review primarily elucidates the molecular mechanisms of cuproptosis, ferroptosis, and PANoptosis and their complex effects on tumor cells and the TME. This review also summarizes the exploration of nanoparticle applications in tumor therapy based on in vivo and in vitro evidence derived from the induction or inhibition of these new RCD pathways.

Integrated multiomics analysis identified comprehensive crosstalk between diverse programmed cell death patterns and novel molecular subtypes in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a highly aggressive malignancy with increasing global prevalence and is one of the leading causes of cancer-related mortality in the human population. Developing robust clinical prediction models and prognostic stratification strategies is crucial for developing individualized treatment plans. A range of novel forms of programmed cell death (PCD) plays a role in the pathological progression and advancement of HCC, and in-depth study of PCD is expected to further improve the prognosis of HCC patients. Sixteen patterns (apoptosis, autophagy, anoikis, lysosome-dependent cell death, immunogenic cell death, necroptosis, ferroptosis, netosis, pyroptosis, disulfidptosis, entotic cell death, cuproptosis, parthanatos, netotic cell death, alkaliptosis, and oxeiptosis) related to PCD were collected from the literatures and used for subsequent analysis. Supervised (Elastic net, Random Forest, XgBoost, and Boruta) and unsupervised (Nonnegative Matrix Factorization, NMF) clustering algorithms were applied to develop and validate a novel classifier for the individualized management of HCC patients at the transcriptomic, proteomic and single-cell levels. Multiple machine learning algorithms developed a programmed cell death index (PCDI) comprising five robust signatures (FTL, G6PD, SLC2A1, HTRA2, and DLAT) in four independent HCC cohorts, and a higher PCDI was predictive of higher pathological grades and worse prognoses. Furthermore, a higher PCDI was found to be correlated with the presence of a repressive tumor immune microenvironment (TME), as determined through an integrated examination of bulk and single-cell transcriptome data. In addition, patients with TP53 mutation had higher PCDI in comparison with TP53 WT patients. Three HCC subtypes were identified through unsupervised clustering (NMF), exhibiting distinct prognoses and significant biological processes, among the three subtypes, PCDcluster 3 was of particular interest as it contained a large proportion of patients with high risk and low metabolic activity. Construction and evaluation of the Nomogram model was drawn based on the multivariate logistic regression analysis, and highlighted the robustness of the Nomogram model in other independent HCC cohorts. Finally, to explore the prognostic value, we also validated the frequent upregulation of DLAT in a real-world cohort of human HCC specimens by qPCR, western blot, and immunohistochemical staining (IHC). Together, our work herein comprehensively emphasized PCD-related patterns and key regulators, such as DLAT, contributed to the evolution and prognosis of tumor foci in HCC patients, and strengthened our understanding of PCD characteristics and promoted more effective risk stratification strategies.