Silencing of activating transcription factor 4 inhibits neuronal necroptosis after intracerebral hemorrhage in vitro / 中国组织工程研究

BACKGROUND:Neuronal necroptosis induced by intracerebral hemorrhage is an important cause of secondary brain injury.Activating transcription factor 4(ATF4)is a member of the transcription activator family,which plays an important role in secondary brain injury after intracerebral hemorrhage.However,the mechanism of ATF4 in neuronal necroptosis after intracerebral hemorrhage remains unclear. OBJECTIVE:To explore the effect of ATF4 silencing(ATF4 small interfering RNA,ATF4 siRNA)on neuronal necroptosis after intracerebral hemorrhage. METHODS:The HT-22 mouse hippocampal neuron cell line and the BV-2 mouse microglial cell line were co-cultured,and hemin was used to mimic an in vitro model of intracerebral hemorrhage.A gradient concentration of hemin was used to treat cells and was set in the interval of 0-100 μmol/L,and the cell viability was evaluated by MTT assay after 24 hours of administration of hemin.The cells were divided into four groups:the blank control group without any intervention;the control group was treated with hemin(50 μmol/L),and the other two groups were treated with negative control small interfering RNA(NC siRNA)and ATF4 small interfering RNA(ATF4 siRNA)48 hours before administration of hemin.After the cells were treated with hemin(50 μmol/L)for 24 hours,PI/Hoechst staining was used to detect neuronal necroptosis.Western blot assay was used to detect the protein expression of ATF4,receptor-interacting protein 3(RIP3),and mixed lineage kinase domain-like protein(MLKL),and double immunofluorescent staining was located in neurons to observe the level of neuronal necroptosis and the regulatory effect of ATF4 on it. RESULTS AND CONCLUSION:(1)50 μmol/L of hemin could induce neuronal necroptosis to a greater extent.(2)The number of PI+/Hoechst+ cells in the control group and NC siRNA group was higher than that in the blank control group(P<0.000 1).The number of PI+/Hoechst+ cells in the ATF4 siRNA group was lower than that in the control group(P<0.000 1).(3)Compared with the control group,the ATF4 siRNA group not only inhibited the expression of ATF4 protein(P<0.001),but also inhibited the expression of RIP3 and MLKL protein(P<0.001).(4)Through double immunofluorescent staining,compared with the control group,the protein expression of RIP3 and MLKL was significantly reduced in the ATF4 siRNA group(P<0.000 1).(5)The results show that the silencing of the ATF4 gene can directly or indirectly inhibit the expression of genes related to neuronal necroptosis after intracerebral hemorrhage,and play a vital role in alleviating secondary brain injury.

Novel programmed cell death in periprosthetic osteolysis / 中国组织工程研究

BACKGROUND:In addition to apoptosis,recent studies have discovered novel forms of programmed cell death in periprosthetic osteolysis,which is involved in regulating local chronic inflammation and the outcome of osteoblast and osteoclast under pathological conditions.This has an important value for the treatment and prognosis of periprosthetic osteolysis. OBJECTIVE:To provide new ideas and strategies for the prevention and treatment of periprosthetic osteolysis by summarizing studies on the novel forms of programmed cell death. METHODS:The first author used the computer to search the articles published from 2005 to 2022.Chinese search terms"wear particles,periprosthetic osteolysis,programmed cell death,apoptosis,autophagy,pyroptosis,necrotizing apoptosis,iron death"were used to search the databases of CNKI,WanFang and VIP.English search terms"osteolysis,wear debris,wear particles,peri*prosthetic osteolysis,PPOL,aseptic loosening,autophagy,regulated cell death,programmed cell death,apoptosis,pyroptosis,autophagic cell death,autophagy,necroptosis,ferroptosis"were used for search in PubMed and Web of Science databases.A total of 68 articles were finally included according to the inclusion criteria. RESULTS AND CONCLUSION:(1)Inadequate or excessive activation of autophagy can cause cell death,inhibit bone formation,and promote bone resorption,leading to bone metabolism disorders and osteolysis.(2)Recent studies have paid close attention to pyroptosis in periprosthetic osteolysis,where the Nod-like receptor,pyrin containing 3 inflammasome plays an important role in local inflammation.Inhibiting pyroptosis can effectively alleviate osteolysis.(3)In vitro studies have shown that necroptosis can inhibit the formation and function of osteoblasts and osteoclasts,affecting the process of osteolysis and destruction.(4)Ferroptosis is the newest form of programmed cell death,which is regulated by complex signaling pathways and mechanisms,but is not yet fully understood.(5)Autophagy,pyroptosis,necroptosis,and ferroptosis play important roles in the development of periprosthetic osteolysis,and their associated signaling pathways and genes require further investigation.

Effects of stress-induced protein Sestrin2 on necroptosis of dendritic cells induced by lipopolysaccharide / 中华危重病急救医学

Objective:To investigate the effect of stress-induced protein Sestrin2 (SESN2) on necroptosis of mouse dendritic cell (DC) induced by lipopolysaccharide (LPS) combined with zVAD, a panaspartate-specific cysteine protease (caspase) inhibitor.Methods:The DC2.4 cell line derived from the bone marrow of mouse in the 3rd to 10th generations was cultured. The cells were stimulated with LPS for 0 hour, 6 hours, 12 hours, and 24 hours, and grouped according to the stimulation time points. Western blotting was performed to determine the protein expression of SESN2 in each group. Overexpression empty lentivirus (NC), SESN2 gene overexpression RNA sequence lentivirus (SESN2 LV-RNA), small interfering empty lentivirus (NS), and SESN2 gene small interfering RNA sequence lentivirus (SESN2 siRNA) were transfected into DC2.4 cells. After 72 hours of transfection, cell fluorescence expression was observed under the inverted fluorescence microscope. Cells in each transfection group were stimulated with LPS for 24 hours. The blank control groups were set up and cultured with phosphate buffered saline (PBS) for 24 hours. Western blotting was performed to measure SESN2 protein expression. In the same groups as above, cells were stimulated with LPS+zVAD for 24 hours. The blank control groups were set up and cultured with PBS for 24 hours. Western blotting was used to determine the expression of mixed lineage kinase domain-like protein (MLKL) and phosphorylated-MLKL (p-MLKL). The p-MLKL levels and the number of positive cells were observed using laser scanning confocal microscopy. The necroptotic cell ratios were assessed by both flow cytometry and Hoechst staining.Results:Compared to the LPS 0 hour group, the expression of SESN2 in the LPS 24 hours group showed a significant increase. Therefore, 24 hours was chosen as the subsequent stimulation time point. After successful lentivirus transduction and 24 hours of cultivation, the MLKL phosphorylation level in the SESN2 siRNA+LPS+zVAD group was significantly higher than that in the NS+LPS+zVAD group. The MLKL phosphorylation in the SESN2 LV-RNA+LPS+zVAD group was significantly lower than that in the NC+LPS+zVAD group. The MLKL phosphorylation levels in both the NS+LPS+zVAD group and the NC+LPS+zVAD group were obviously higher than those in the NS+PBS group and the NC+PBS group, respectively. Laser scanning confocal microscopy showed that the trends in quantity and fluorescence intensity of p-MLKL protein expressions were consistent with the above results. The results from flow cytometry analysis and Hoechst staining showed that the rates of cell necrotic apoptosis in SESN2 siRNA+LPS+zVAD group were significantly higher than those in NS+LPS+zVAD group [flow cytometry analysis: (30.800±1.153)% vs. (20.800±1.114)%, Hoechst staining: (75.267±0.451)% vs. (46.267±3.371)%, both P < 0.05], indicating that knocking down SESN2 further exacerbated the occurrence of necroptosis. The necrotic apoptosis rates in SESN2 LV-RNA+LPS+zVAD group were significantly lower than those in NC+LPS+zVAD group [flow cytometry analysis: (7.160±0.669)% vs. (19.240±2.322)%, Hoechst staining: (32.433±3.113)% vs. (48.567±4.128)%, both P < 0.05], indicating that overexpressing SESN2 reversed such response and markedly reduced the proportion of necroptotic cells compared to the corresponding empty vector group. Conclusion:SESN2 exhibits an inhibitory effect on necroptosis of DC in sepsis. Targeted SESN2 expression may regulate the process of DC-mediated immune response in sepsis.

Effect of naringenin regulating RIP1-RIP3-MLKL signaling pathway on apoptosis of ovarian granulosa cells in rats with polycystic ovary syndrome / 中国药理学通报

Aim Based on the apoptotic pathway mediated by receptor interacting protein kinase(RIP)1-RIP3-mixed spectrum kinase domain like protein(MLKL), to explore the effects of naringenin on ovarian granulosa cell apoptosis in rats with polycystic ovary syndrome(PCOS). Methods SD rats were randomly assigned into normal control group, model group, naringenin group, RIP1 inhibitor(Nec-1)group, RIP1-RIP3-MLKL necrosis signal activator(Z-VAD-fmk)group, naringenin+Z-VAD-fmk group, 15 rats per group. ELISA method was performed to measure the levels of IL-1β and TNF-α in ovarian tissue. HE method was performed to observe the shape of the ovary. Granular cells were isolated from ovarian tissue, and flow cytometry was performed to measure apoptosis rate and necrosis rate. Immunohistochemistry was performed to measure the positive expression of p-RIP1 in ovarian tissue. Western blot was employed to detect the expression of RIP1-RIP3-MLKL pathway. Results RIP1 specific inhibitor Nec-1 and naringenin could block the phosphorylation and activation of RIP1, inhibit the RIP1-RIP3-MLKL signaling pathway, reduce the inflammation level in PCOS rats, and alleviate the necrosis and apoptosis of ovarian granulosa cells(P<0.05). Z-VAD-fmk could promote the activation of RIP1-RIP3-MLKL pathway, aggravate the apoptosis of ovarian granulosa cells, and partially weaken the anti-apoptosis effect of naringenin(P<0.05). Conclusions Naringenin may inhibit the apoptosis of ovarian granulosa cells in PCOS rats by blocking the activation of the necrotic apoptotic pathway mediated by RIP1-RIP3-MLKL.

Research progress in RIPK3 and its inhibitors / 中国药理学通报

Receptor-interacting serine/threonine-protein kinase 3(RIPK3),a member of the RIP kinase family,plays an important role in cell death,especially in necroptosis. In addition,RIPK3 is also involved in apoptosis and pyroptosis,suggesting that RIPK3 may be the intersection of multiple cell death and it possesses the potential to be a target for precise regulation of cell death. According to the kinase binding mode,current RIPK3 inhibitors can be classified into type ,type Ⅱ and other types. This review summarizes the research progress in the role of RIPK3 in cell death and its inhibitors,which is of great significance in seeking drugs for the treatment of injury-related diseases.

Structure-based development of potent and selective type-II kinase inhibitors of RIPK1

Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) functions as a key regulator in inflammation and cell death and is involved in mediating a variety of inflammatory or degenerative diseases. A number of allosteric RIPK1 inhibitors (RIPK1i) have been developed, and some of them have already advanced into clinical evaluation. Recently, selective RIPK1i that interact with both the allosteric pocket and the ATP-binding site of RIPK1 have started to emerge. Here, we report the rational development of a new series of type-II RIPK1i based on the rediscovery of a reported but mechanistically atypical RIPK3i. We also describe the structure-guided lead optimization of a potent, selective, and orally bioavailable RIPK1i, 62, which exhibits extraordinary efficacies in mouse models of acute or chronic inflammatory diseases. Collectively, 62 provides a useful tool for evaluating RIPK1 in animal disease models and a promising lead for further drug development.

To Explore the Harmful Outcomes Induced by Traditional Chinese Medicine Based on the Mechanism of Programmed Cell Death and Inflammatory Response / 世界科学技术-中医药现代化

Objective In this paper,the harmful effects and mechanisms induced by traditional Chinese medicine were expounded by combining the mechanism of programmed cell death and inflammatory reaction.It is expected to provide data support and theoretical reference for the rational use of traditional Chinese medicine and toxicology research.Methods By systematically analyzing the correlation between cell death and inflammatory response,the molecular mechanisms of pyroptosis,programmed cell necrosis and ferroptosis at home and abroad were summarized,and the harmful outcomes induced by traditional Chinese medicine were further discussed.Results Different toxic traditional Chinese medicines and their active ingredients have different tolerances to biological organisms.Programmed cell death is an important molecular mechanism for the toxicity of traditional Chinese medicines.Its signaling pathways are complex and diverse and are often accompanied by inflammatory reactions.Both of them have a certain effect on the toxic effects of traditional Chinese medicine.Conclusion Traditional Chinese medicine can provide inflammatory mediators for inflammatory response pathways through cell death or change the physiological balance of cells,thereby inducing inflammatory cascade reactions and promoting harmful outcomes in various systems of the body under the dual effects of cell death and inflammatory response.

A preliminary study on the effect of arsenic exposure on necroptosis of mouse myocardial cells / 中华地方病学杂志

Objective:To study the effects of arsenic exposure on necroptosis pathway and inflammatory response of mouse myocardial cells.Methods:Sixty male C57BL/6J mice were randomly divided into control group (group C) and low, medium, and high dose arsenic exposure groups (groups L, M, H) based on body weight using a random number table method. Each group had 15 mice, and they drank 0.00, 0.15, 1.50, and 15.00 mg/L arsenic trioxide (As 2O 3) solution prepared with deionized water. The exposure period was 12 weeks. Hematoxylin-eosin (HE) staining and Masson trichrome staining of paraffin-embedded heart tissues were used to observe the histopathology changes of the heart. Transmission electron microscopy (TEM) was used to evaluate the ultrastructural changes of myocardial cells. The quantitative real-time PCR (qRT-PCR) was used to detect the mRNA expression of inflammatory genes [tumor necrosis factor (TNF)-α and interleukin(IL)-6] and the genes involved in necroptosis pathway [receptor-interacting protein (RIP) 1, RIP3 and mixed-lineage kinase domain-like protein (MLKL)]. Protein expressions of RIP1 and RIP3 in the heart were assessed by western blotting. Results:Histopathological examination results showed there were myocardial necrosis, inflammatory cells infiltration and fibroblasts hyperplasia and other changes in groups M and H. TEM analysis revealed marked ultrastructural changes in groups M and H, including fractured myofibril, fractured Z lines of sarcomere, and swollen mitochondria with fractured cristae. Compared with group C (1.00 ± 0.00), the mRNA expression of RIP1 in group H was significantly up-regulated (1.41 ± 0.06, P < 0.05); the mRNA expressions of RIP3 (1.29 ± 0.14, 1.56 ± 0.08), MLKL (1.23 ± 0.05, 1.36 ± 0.07), TNF-α (2.20 ± 0.10, 2.23 ± 0.18) and IL-6 (1.87 ± 0.16, 1.63 ± 0.15) were significantly up-regulated in groups M and H ( P < 0.05). The protein expressions of RIP1 (0.43 ± 0.04, 0.50 ± 0.04) and RIP3 (0.68 ± 0.02, 0.84 ± 0.05) in groups M and H were higher than those in group C (0.25 ± 0.01, 0.45 ± 0.04, P < 0.05). Conclusion:Subchronic arsenic exposure induces histopathological changes such as myocardial necrosis and fibrosis in mice, inducing necroptosis and inflammatory reactions in myocardial cells.

Effect of Usnic Acid on Neuronal Necroptosis in Rats with Cerebral Infarction by Regulating the RIPK1/RIPK3/MLKL Signaling Pathway / 中药新药与临床药理

Objective To investigate the impact of usnic acid on neuronal necroptosis in rats with cerebral infarction by regulating the receptor-interacting protein kinase 1(RIPK1)/receptor-interacting protein kinase 3(RIPK3)/mixed lineage kinase domain-like protein(MLKL)signaling pathway.Methods The rat model of cerebral infarction was established by middle cerebral artery occlusion and reperfusion(MCAO/R).The successfully modeled rats were divided into model group,NEC-1(RIP1 inhibitor)group,low-,medium-,and high-dose of usnic acid groups,with 20 rats in each group.Another 20 rats were selected as a sham-operation group.After 3 days of drug intervention,the modified Neurological Severity Scale(mNSS)was applied to evaluate the degree of neurological damage of rats in each group.TTC staining was applied to detect the volume of cerebral infarction.HE staining was selected to observe pathological damage in brain tissue.PI/NeuN staining was selected to observe neuronal necrosis.RT-qPCR was used to detect mRNA levels of RIPK1,RIPK3 and MLKL in rat ischemic brain tissue.Western Blot was used to determine the expressions of RIPK1/RIPK3/MLKL signaling pathway related proteins in rat ischemic brain tissue.Results Compared with the sham-operation group,the neural cells in the model group showed structural damage,cell disrupted,deformation,and nuclear pyknosis,furthermore,the mNSS score,the cerebral infarction volume,proportion of PI-positive neurons were significantly increased(P＜0.05).The mRNA levels of RIPK1,RIPK3,MLKL in brain tissue,ratio of p-RIPK1/RIPK1,and the levels of RIPK3 and MLKL proteins were obviously increased(P＜0.05).Compared with the model group,the damage degree of neurocyte morphology in the low-,medium-,and high-dose of usnic acid groups was gradually alleviated,the nuclear membrane was gradually became clear,and the cell body was gradually returned to normal.The neurocyte morphology in the NEC-1 group was basically intact,and the nuclear membrane was basically clear.The mNSS score,cerebral infarction volume and proportion of PI-positive neurons in NEC-1 group and usnic acid groups were significantly decreased(P＜0.05).The mRNA levels of RIPK1,RIPK3,MLKL,ratio of p-RIPK1/RIPK1,and levels of RIPK3 and MLKL proteins in brain tissue were obviously reduced in usnic acid groups and NEC-1 group.Also,there was dose-dependent decrease in usnic acid groups(P＜0.05).No statistically obvious difference was found between the high-dose usnic acid group and the NEC-1 group(P＞0.05).Conclusion Usnic acid inhibits neuronal necroptosis in rats with cerebral infarction by inhibiting the RIPK1/RIPK3/MLKL signaling pathway,thereby alleviating brain injury in rats with cerebral infarction.

Programmed cell death and infectious diseases / 中国热带医学

@#Abstract: Cell death is a fundamental biological phenomenon that is essential for the survival and development of organisms. Cell death can be either a spontaneous programmed process by the host or an accidentally triggered process. According to the different signaling pathway activated by various stimulates, programmed cell death exhibits the lytic or non-lytic morphology. For example, apoptosis, a typical non-lytic form of cell death, exhibits cell shrinkage and induces the formation of apoptotic bodies. Pyroptosis mediated by cysteine-containing aspartate-specific protease-1/11 (caspase-1/11) and necroptosis can induce inflammatory reactions and promote cell lysis to release inflammatory cytokines via triggering the pore-forming mechanism of the cell membrane, representing a typical modes of lytic cell death. In addition, the release of reactive oxygen species caused by the damaged mitochondria may further trigger ferroptosis during the pathogen infection. Programmed cell death can play an immune defensive role by eliminating infected cells and intracellular pathogens and stimulating the innate immune response through the resulting cell corpses. Here, we discuss the molecular mechanisms of five programmed cell death pathways: apoptosis, pyroptosis, ferroptosis, necroptosis and PANoptosis. We describe their roles in the innate immune defense against bacterial infections and give a brief statement of the interactions between the different programmed cell death, hoping to provide new insights for in-depth study of the pathogenic mechanisms of infectious diseases.

Advances on mechanisms of regulated cell death in neurotoxicity of aluminum / 环境与职业医学

Aluminum is a light metal which is rich in the earth's crust and widely used. Recently, the adverse health effects of environmental and occupational aluminum exposure on human have attracted more and more attention. Aluminum exposure has toxic effects on the central nervous system and is believed to be closely related to the development and progression of Alzheimer's disease. The neurotoxic mechanism of aluminum is complex, especially the role of regulated cell death (RCD) in aluminum-induced neuronal death remains to be further studied. RCD refers to all modes of cell death regulated by multiple intracellular signal transduction pathways under physiological and pathological conditions, including apoptosis, necroptosis, autophagy, pyroptosis, and ferroptosis. This review summarized the morphological characteristics and mechanisms of each RCD mode in the process of aluminum-induced neuronal death, and discussed the relationship and transformation between different RCD modes, providing a new scientific basis for future studies on the treatment and intervention of neurotoxicity induced by aluminum exposure.

PANoptosis： Molecular Mechanism of Action and Effects on Blinding Eye Diseases / 中山大学学报(医学科学版)

Previous studies focused on the unique regulatory mechanisms of different cell death pathways. However， recent studies highlight crosstalk and co-ordination between these pathways and initiate a new cell death process called PANoptosis （pyroptosis， apoptosis， necroptosis）. PANoptosis is an inflammatory programmed cell death pathway regulated by the PANoptosome complex with critical features of pyroptosis， and/or necroptosis but cannot be characterized by any of the death modes of pyroptosis， apoptosis or necroptosis alone. By activating the PANoptosis pathway， some triggers like bacterial， viral， and fungal infections can cause death of the host. This review explains the PANoptosis-related routes， regulators and their potential effects on blinding eye diseases.

Progress in study on the final executor of necroptosis MLKL and its inhibitors / 中南大学学报(医学版)

Necroptosis is one of the regulated cell death, which involves receptor interacting protein kinase (RIPK) 1/RIPK3/mixed lineage kinase domain like protein (MLKL) signaling pathway. Among them, MLKL is the final execution of necroptosis. The formation of RIPK1/RIPK3/MLKL necrosome induces the phosphorylated MLKL, and the activated MLKL penetrates into the membrane bilayer to form membrane pores, which damages the integrity of the membrane and leads to cell death. In addition to participating in necroptosis, MLKL is also closely related to other cell death, such as NETosis, pyroptosis, and autophagy. Therefore, MLKL is involved in the pathological processes of various diseases related to abnormal cell death pathways (such as cardiovascular diseases, neurodegenerative diseases and cancer), and may be a therapeutic target of multiple diseases. Understanding the role of MLKL in different cell death can lay a foundation for seeking various MLKL-related disease targets, and also guide the development and application of MLKL inhibitors.

Protective role and mechanism of human umbilical cord mesenchymal stem cell-derived exosome in renal ischemia-reperfusion injury / 器官移植

Objective To investigate the protective effect of human umbilical cord mesenchymal stem cell-derived exosome (hucMSC-Exo) on renal ischemia-reperfusion injury (IRI), and to clarify the critical role and regulating mechanism of transient receptor potential canonical (TRPC) 6/poly adenosine-diphosphate-ribose polymerase (PARP) 1 signaling pathway during this process. Methods The hucMSC-Exo was extracted by ultracentrifugation, and identified by transmission electron microscope (TEM), nanoparticle tracing analysis and Western blot. SD rats were randomly divided into the sham operation group (group S), sham operation+TRPC6 inhibitor SKF96365 group (group SS), renal IRI group (group IRI), exosome treatment group (group EXO) and exosome +TRPC6 inhibitor SKF96365 group (group ES), with 6 rats in each group. Serum creatinine and blood urea nitrogen levels were detected. Pathological changes of renal tissues were observed by hematoxylin-eosin (HE) staining and Paller score was calculated. The expression levels of key molecules of necroptosis in rat renal tissues, including receptor-interacting protein kinase (RIPK)1, RIPK3 and mixed-lineage kinase domain-like protein (MLKL), TRPC6 and PARP1, were detected by Western blot. Results Typical saucer-like structure was observed under TEM. Nanoparticle tracing analysis showed that the average diameter of the extracted substance was 125.9 nm. Western blot revealed that the surface markers of CD9, CD63 and CD81 were positively expressed, confirmed that the extracted substance was exosome. Compared with group S, the serum creatinine and blood urea nitrogen levels were up-regulated, the pathological damage of renal tissues was worsened, Paller score was elevated, the relative expression levels of TRPC6 and PARP1 proteins were down-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were up-regulated in group IRI (all P < 0.05). Compared with group IRI, the serum creatinine and blood urea nitrogen levels were down-regulated, the pathological damage of renal tissues was mitigated, Paller score was decreased, the relative expression levels of TRPC6 and PARP1 proteins were up-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were down-regulated in group EXO (all P < 0.05). Compared with group EXO, the serum creatinine and blood urea nitrogen levels were up-regulated, the pathological damage of renal tissues was aggravated, Paller score was increased, the relative expression levels of TRPC6 and PARP1 proteins were down-regulated, and the relative expression levels of RIPK1, RIPK3 and MLKL proteins were up-regulated in group ES (all P < 0.05). Conclusions hucMSC-Exo may alleviate the necroptosis induced by renal IRI in rat models, which is related to the activation of TRPC6/PARP1 signaling pathway.

Progress of Different Programmed Cell Death Pathways in Kidney Cancer / 肿瘤防治研究

Programmed cell death (PCD) is a genetically determined, active and orderly cell death in the organism, and it affects the evolution of the organism, maintenance of its homeostasis, and development of several tissues and organs. The abnormal regulation of this process is closely related to various human diseases, including cancer. The identified pathways of PCD include apoptosis, autophagy, necroptosis, pyroptosis, and ferroptosis, which can be activated when cells are stimulated by various internal and external environmental factors. These pathways can induce cell death or maintain cell survival in kidney cancer cells under the regulation of various signaling molecules, thus affecting tumor progression or therapeutic efficacy. In this paper, the role of these PCD pathways in the development of kidney cancer was reviewed in light of recent research advances to provide new directions for the in-depth study of the pathogenesis of kidney cancer and the development of targeted antitumor drugs.

Effects and mechanisms of total flavones of Abelmoschus manihot in inhibiting podocyte necroptosis and renal fibrosis in diabetic kidney disease / 中国中药杂志

Previous studies have shown that high blood glucose-induced chronic microinflammation can cause inflammatory podocyte injury in patients with diabetic kidney disease(DKD). Therein, necroptosis is a new form of podocyte death that is closely associated with renal fibrosis(RF). To explore the effects and mechanisms in vivo of total flavones of Abelmoschus manihot(TFA), an extract from traditional Chinese herbal medicine Abelmoschus manihot for treating kidney diseases, on podocyte necroptosis and RF in DKD, and to further reveal its scientific connotation with multi-pathway and multi-target, the authors randomly divided all rats into four groups: a namely normal group, a model group, a TFA group and a rapamycin(RAP) group. After the modified DKD rat models were successfully established, four group rats were given double-distilled water, TFA suspension and RAP suspension, respectively by gavage every day. At the end of the 4th week of drug treatment, all rats were sacrificed, and the samples of their urine, blood and kidneys were collected. And then, the various indicators related to podocyte necroptosis and RF in the DKD model rats were observed, detected and analyzed, respectively. The results indicated that, general condition, body weight(BW), serum creatinine(Scr), urinary albumin(UAlb), and kidney hypertrophy index(KHI) in these modified DKD model rats were both improved by TFA and RAP. Indicators of RF, including glomerular histomorphological characteristics, fibronectin(FN) and collagen type Ⅰ(collagen Ⅰ) staining extent in glomeruli, as well as the protein expression levels of FN, collagen Ⅰ, transforming growth factor-β1(TGF-β1) and Smad2/3 in the kidneys were improved respectively by TFA and RAP. Podocyte damage, including foot process form and the protein expression levels of podocin and CD2AP in the kidneys was improved by TFA and RAP. In addition, tumor necrosis factor-α(TNF-α)-mediated podocyte necroptosis in the kidneys, including the morphological characteristics of podocyte necroptosis, the extent and levels of the protein expression of TNF-α and phosphorylated mixed lineage kinase domain like pseudokinase(p-MLKL) was improved respectively by TFA and RAP. Among them, RAP had the better effect on p-MLKL. More importantly, the activation of the receptor interacting serine/threonine protein kinase 1(RIPK1)/RIPK3/MLKL signaling axis in the kidneys, including the expression levels of its key signaling molecules, such as phosphorylated receptor interacting serine/threonine protein kinase 1(p-RIPK1), p-RIPK3, p-MLKL and cysteinyl aspartate specific proteinase-8(caspase-8) was improved respectively by TFA and RAP. Among them, the effect of TFA on p-RIPK1 was superior. On the whole, in this study, the authors demonstrated that TFA alleviates podocyte necroptosis and RF in DKD through inhibiting the activation of the TNF-α-mediated RIPK1/RIPK3/MLKL signaling axis in diabetic kidneys. The authors' findings provide new pharmacological evidence to reveal the scientific connotation of TFA in treating RF in DKD in more depth.

Resveratrol Prevents Vibrio vulnificus-Induced Sepsis by Attenuating Necroptosis / 生物医学与环境科学（英文）

OBJECTIVE@#This study investigated how the natural phytophenol and potent SIRT1 activator resveratrol (RSV) regulate necroptosis during Vibrio vulnificus (V. vulnificus)-induced sepsis and the potential mechanism.@*METHODS@#The effect of RSV on V. vulnificus cytolysin (VVC)-induced necroptosis was analyzed in vitro using CCK-8 and Western blot assays. Enzyme-linked immunosorbent assays and quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry and survival analyses were performed to elucidate the effect and mechanism of RSV on necroptosis in a V. vulnificus-induced sepsis mouse model.@*RESULTS@#RSV relieved necroptosis induced by VVC in RAW264.7 and MLE12 cells. RSV also inhibited the inflammatory response, had a protective effect on histopathological changes, and reduced the expression level of the necroptosis indicator pMLKL in peritoneal macrophages, lung, spleen, and liver tissues of V. vulnificus-induced septic mice in vivo. Pretreatment with RSV downregulated the mRNA of the necroptosis indicator and protein expression in peritoneal macrophages and tissues of V. vulnificus-induced septic mice. RSV also improved the survival of V. vulnificus-induced septic mice.@*CONCLUSION@#Our findings collectively demonstrate that RSV prevented V. vulnificus-induced sepsis by attenuating necroptosis, highlighting its potency in the clinical management of V. vulnificus-induced sepsis.

Polissacarídeos de Lentinula edodes suprimem a expressão de citocinas pró-inflamatórias e de colite em camundongos / Lentinula edodes polysaccharides suppressed pro-inflammatory cytokines expression and colitis in mice

ABSTRACT Background: Polysaccharides from edible mushrooms possess immunomodulatory, anti-inflammatory, and anti-tumor activities. Recent studies indicated that necroptosis plays a role in the pathogenesis of inflammatory diseases and mediates increased expression of inflammatory cytokines. Objective: Therefore, it is imperative to determine the impact of polysaccharide extract from Lentinula edodes (L. edodes) on inflammatory cytokines in experimental model of colitis in mice. Methods: Female C57BL/6 mice divided into three or four mice per group were used for this study. Polysaccharide sample was orally administered to mice prior to (7 days) and during colitis induction with 2.5% dextran sodium sulfate (7 days), followed by additional 3 days of administration. Changes in body weight and colon length were used as markers for colitis, and pro-inflammatory cytokines and tumor necrosis factor receptor 1 (TNFR1) expressions, as well as necroptosis were analyzed in the colon of colitis mice. Data obtained were analysed by Tukey-Kramer and two-tailed standard t tests. Results: The results indicated that the polysaccharide sample suppressed colitis in mice using effects on the body weight and colon length as markers. Also, it was demonstrated that necrostatin-1, a specific inhibitor of necroptosis, suppressed the expression of interleukin (IL)-8, a pro-inflammatory chemokine, in Caco-2 cells induced necroptosis induced by zVAD and TNF-α, an indication that necroptosis may be involved in the expression of pro-inflammatory cytokines. Moreover, the polysaccharide sample suppressed the expression of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α, IL-6, IL-1β, and interferon (IFN)-γ in the colon of mice. Conclusion: These results suggested that the suppressive effects of the polysaccharide sample on inflammatory cytokines expression may contribute to its anti-colitis effect, and so may serve as a potent therapeutic agent against inflammatory bowel disease.

RESUMO Contexto: Polissacarídeos de cogumelos comestíveis possuem atividades imunomodulatórias, anti-inflamatórias e anti-tumorais. Estudos recentes indicaram que a necroptose desempenha um papel na patogênese de doenças inflamatórias e regula o aumento da expressão de citocinas inflamatórias. Objetivo: Torna-se imprescindível determinar o impacto do extrato de polissacarídeo de Lentinula edodes (L. edodes) em citocinas inflamatórias em modelo experimental de colite em camundongos. Métodos: Foram utilizados para este estudo os camundongos C57BL/6 femininos divididos em três ou quatro camundongos por grupo. A amostra de polissacarídeo foi administrada oralmente em camundongos antes (7 dias) e durante a indução de colite com sulfato de dextran sulfato de sódio (7 dias), seguido por 3 dias adicionais de administração. Alterações no peso corporal e comprimento do cólon foram utilizadas como marcadores para colite, e citocinas pró-inflamatórias e tumores receptor fator 1 (TNFR1), bem como necroptose foram analisadas no cólon de camundongos colite. Os dados obtidos foram analisados por testes Tukey-Kramer e testes padrão t de duas caudas. Resultados: Os resultados indicaram que a amostra de polissacarídeo suprimiu colite em camundongos usando efeitos sobre o peso corporal e o comprimento do cólon como marcadores. Além disso, foi demonstrado que a necrostatina-1, inibidora específica da necroptose, suprimiu a expres são de interleucina (IL)-8, uma quimiocina pró-inflamatória, em células caco-2 induzidas necroptose induzidas por zVAD e TNF-α, uma indicação de que a necroptose pode estar envolvida na expressão de citocinas pro-inflamatórias. Além disso, a amostra de polissacarídeo suprimiu a expressão de citocinas pró-inflamatórias, como o fator de necrose tumoral (TNF)-α, IL-6, IL-1β e interferon (IFN)-γ no cólon dos camundongos. Conclusão: Esses resultados sugeriram que os efeitos supressivos da amostra de polissacarídeo na expressão de citocinas inflamatórias podem contribuir para o seu efeito anti-colite, podendo, portanto, servir como um potente agente terapêutico contra doença inflamatória intestinal.

Preliminary evidence for the presence of multiple forms of cell death in diabetes cardiomyopathy

Diabetic mellitus (DM) is a common degenerative chronic metabolic disease often accompanied by severe cardiovascular complications (DCCs) as major causes of death in diabetic patients with diabetic cardiomyopathy (DCM) as the most common DCC. The metabolic disturbance in DCM generates the conditions/substrates and inducers/triggers and activates the signaling molecules and death executioners leading to cardiomyocyte death which accelerates the development of DCM and the degeneration of DCM to heart failure. Various forms of programmed active cell death including apoptosis, pyroptosis, autophagic cell death, autosis, necroptosis, ferroptosis and entosis have been identified and characterized in many types of cardiac disease. Evidence has also been obtained for the presence of multiple forms of cell death in DCM. Most importantly, published animal experiments have demonstrated that suppression of cardiomyocyte death of any forms yields tremendous protective effects on DCM. Herein, we provide the most updated data on the subject of cell death in DCM, critical analysis of published results focusing on the pathophysiological roles of cell death, and pertinent perspectives of future studies.

Aging-elevated inflammation promotes DNMT3A R878H-driven clonal hematopoiesis

Aging-elevated DNMT3A R882H-driven clonal hematopoiesis (CH) is a risk factor for myeloid malignancies remission and overall survival. Although some studies were conducted to investigate this phenomenon, the exact mechanism is still under debate. In this study, we observed that DNMT3A R878H bone marrow cells (human allele: DNMT3A R882H) displayed enhanced reconstitution capacity in aged bone marrow milieu and upon inflammatory insult. DNMT3A R878H protects hematopoietic stem and progenitor cells from the damage induced by chronic inflammation, especially TNFα insults. Mechanistically, we identified that RIPK1-RIPK3-MLKL-mediated necroptosis signaling was compromised in R878H cells in response to proliferation stress and TNFα insults. Briefly, we elucidated the molecular mechanism driving DNMT3A R878H-based clonal hematopoiesis, which raises clinical value for treating DNMT3A R882H-driven clonal hematopoiesis and myeloid malignancies with aging.