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.

Advances in relationship between pyroptosis and pulmonary arterial hypertension and therapeutic drugs / 中国药理学通报

Pyroptosis is the programmed death of cells accompanied by an inflammatory response and is widely involved in the development of a variety of diseases, such as infectious diseases, cardiovascular diseases, and neurodegeneration. It has been shown that cellular scorching is involved in the pathogenesis of pulmonary arterial hypertension ( PAH) in cardiovascular diseases. Patients with PAH have perivascular inflammatory infiltrates in lungs, pulmonary vasculopathy exists in an extremely inflam-matory microenvironment, and pro-inflammatory factors in cellular scorching drive pulmonary vascular remodelling in PAH patients. This article reviews the role of cellular scorch in the pathogenesis of PAH and the related research on drugs for the treatment of PAH, with the aim of providing new ideas for clinical treatment of PAH.

Tripterine promotes pyroptosis of liver cancer cells by regulating ATF4/caspase-3/GSDME signaling pathway / 中国药理学通报

Aim To explore the new mechanism of triptolide (TRI) inhibiting the progression of hepatocellular carcinoma (HCC) . Methods Different concentrations (0, 0 . 5, 2, and 8 jjunol • L~) of TRI were administered to act on liver cancer cells, and then the cell phenotypes and possible mechanisms were explored using experimental methods such as CCK-8, cell cloning, Transwell, and protein immunoblotting; siRNA was used to interfere with the target gene GSDME and its role was determined. Finally, the mechanism of TRI inhibiting the growth of HCC cells in vivo was validated using a transplanted tumor model. Results TRI could inhibit the proliferation, cloning, and invasion of HCC cells, and promote cell apoptosis. Immunoblotting results showed that the expression of GSDME was significantly upregulated in HepG2 or He-pal-6 hepatocellular carcinoma after TRI treatment, while the expression of cleaved caspase-3 and PARP also significantly increased. Knocking out GSDME could partially reverse TRI-induced cell apoptosis. At the same time, cells knocked down by GSDME had stronger cloning and migration abilities, and the apoptosis rate was reduced compared to the TRI treatment group alone. In vivo experiments showed that TRI inhibited HCC tumor growth, and the TRI + siGSDME group had a faster tumor growth rate than the TRI treatment group alone did. In addition, after TRI stimulation, p-eIF2a and ATF4 in HepG2 and Hepal-6 cells significantly increased. The immunofluorescence results showed a dose-dependent increase in the number of ATF4 positive cells in HepG2 and Hepal-6 cells after TRI stimulation. Conclusion The inhibitory effect of TRI on the growth and invasion of liver cancer cells may be related to its regulation of the ATF4/caspase-3/GSDME signaling pathway and promotion of liver cancer cell apoptosis.

Salvianolic Acid F Regulates Bax/Caspase-3/GSDME Signaling Pathway to Inhibit Pyroptosis of HK-2 Cells / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of salvianolic acid F （Sal F） in repairing the high glucose-induced injury in human kidney-2 （HK-2） cells via the B-cell lymphoma-2 （Bcl-2）-associated X protein （Bax）/cysteinyl aspartate-specific proteinase 3 （Caspase-3）/gasdermin-E （GSDME） pathway. MethodThe cell counting kit-8 （CCK-8） was used to measure the relative viability of HK-2 cells exposed to high glucose and different concentrations （2.5， 5， 10， 20 μmol·L-1） of Sal F and the relative viability of HK-2 cells treated with Sal F for different time periods. The levels of lactate dehydrogenase （LDH） and interleukin-1β （IL-1β） in the supernatant of the cell culture were measured by the LDH assay kit and enzyme-linked immunosorbent assay （ELISA） kit， respectively. Flow cytometry combined with Annexin V-FITC/propidium iodide （PI） and Hoechst 33342/PI staining was employed to reveal the proportion of PI-positive HK-2 cells exposed to high glucose. Western blotting was employed to determine the protein levels of Bax， Bcl-2， cytochrome C， cysteinyl aspartate-specific proteinase （Caspase）-9， Caspase-3， and GSDME in the HK-2 cells exposed to high glucose and treated with Sal F. The 2，7-dichlorodihydrofluorescein diacetate fluorescence probe （DCFH-DA） and mitochondrial membrane potential assay kit （JC-1） were used to determine the production of reactive oxygen species （ROS） and the mitochondrial membrane potential in the HK-2 cells exposed to high glucose and treated with Sal F. ResultCompared with the blank group， the model group showed decreased cell viability （P<0.01）， elevated levels LDH and IL-1β， increased proportion of PI-positive cells （P<0.01）， up-regulated protein levels of Bax， cytochrome C， Caspase-9， Caspase-3， and GSDME （P<0.01）， down-regulated protein level of Bcl-2 （P<0.01）， decreased mitochondrial membrane potential， and excessive ROS accumulation. Compared with the model group， Sal F repaired the high glucose-induced injury in HK-2 cells （P<0.05）， lowered the levels of LDH and IL-1β （P<0.05， P<0.01）， and decreased the proportion of PI-positive cells （P<0.01）. In addition， Sal F down-regulated the protein levels of Bax， cytochrome C， Caspase-9， Caspase-3， and GSDME and up-regulated the protein level of Bcl-2 （P<0.05， P<0.01）， increased the mitochondrial membrane potential， and decreased the accumulation of ROS in HK-2 cells. ConclusionSal F can reduce the production of ROS， restore the balance of mitochondrial membrane potential， and inhibit pyroptosis via the Bax/Caspase-3/GSDME signaling pathway to repair the high glucose-induced injury in HK-2 cells.

Scutellariae Radix-Coptidis Rhizoma Treats Atherosclerosis via NLRP3 Inflammasome-mediated Pyroptosis of Macrophages / 中国实验方剂学杂志

ObjectiveTo investigate the therapeutic effect of Scutellariae Radix-Coptidis Rhizoma （SRCR） on atherosclerosis （AS） in mice and the effect of SRCR on macrophage pyroptosis in plaques via NOD-like receptor thermal protein domain-associated protein 3 （NLRP3） inflammasomes. MethodApoE-/- mice were fed with a high-fat diet for the modeling of AS and randomized into model， atorvastatin （5 mg·kg-1）， and low-， medium-， and high-dose （1.95， 3.9， 7.8 g·kg-1， respectively） SRCR groups. Normal C57BL/6J mice were selected as the control group. After 8 weeks of administration， hematoxylin-eosin staining was used to observe the pathological status of the aortic plaque. The lipid accumulation in aortic plaque was observed by oil red O staining. The serum levels of total cholesterol （TC）， triglyceride （TG）， high-density lipoprotein cholesterol （HDL-C）， and low-density lipoprotein cholesterol （LDL-C） in mice were measured. Immunofluorescence double staining was employed to detect the co-localized expression of EGF-like module-containing mucin-like hormone receptor-like 1 （EMR1）/NLRP3 and EMR1/gasdermin D （GSDMD）. The serum levels of interleukin-1β （IL-1β） and interleukin-18 （IL-18） were determined by enzyme-linked immunosorbent assay （ELISA）. The protein levels of NLRP3， apoptosis-associated speck-like protein （ASC）， Caspase-1， cleaved Caspase-1， GSDMD， N-terminus of GSDMD （GSDMD-NT）， pro-IL-1β， IL-1β， and IL-18 were determined by Western blot， and the mRNA levels of NLRP3， ASC， Caspase-1， GSDMD， IL-1β， and IL-18 were determined by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the control group， the model group showed obvious plaques， elevated serum levels of TG， TC， LDL-C， IL-1β， and IL-18 （P<0.01）， lowered serum level of HDL-C （P<0.01）， and up-regulated expression of NLRP3 inflammasomes and molecules related to pyroptosis in the aortic plaques （P<0.01）. Compared with the model group， SRCR， especially at the medium and high doses， alleviated the plaque pathology， reduced the lipid content in plaques （P<0.05， P<0.01）， recovered the serum lipid levels （P<0.05）， reduced the macrophage recruitment （P<0.01）， activation of NLRP3 inflammasomes， and pyroptosis in aortic root plaques （P<0.05）， lowered the serum IL-1β and IL-18 levels （P<0.01）， and down-regulated the protein levels of NLRP3， ASC， Caspase-1， cleaved Caspase-1， GSDMD， GSDMD-NT， pro-IL-1β， IL-1β， and IL-18 （P<0.05） and the mRNA levels of NLRP3， ASC， Caspase-1， GSDMD， IL-1β， and IL-18 in the aortic tissue （P<0.05）. ConclusionSRCR exerts a therapeutic effect on high-fat diet-induced AS in mice by inhibiting the activation NLRP3 inflammasomes and reducing the pyroptosis of macrophages in plaques.

Role of NOD-like receptor protein 3 inflammasome in the development and progression of hepatocellular carcinoma / 临床肝胆病杂志

In recent years， NOD-like receptor protein 3 （NLRP3） inflammasome in tumors has become a research hotspot， especially in melanoma， colorectal cancer， lung cancer， and breast cancer， and more and more evidence has shown that inflammation plays a role in the development， progression， angiogenesis， and invasion of cancer. Hepatocellular carcinoma （HCC） is the most common type of primary liver cancer， and there are still controversies over the role of NLRP3 inflammasome in the development and progression of HCC. Therefore， this article reviews the potential impact of NLRP3 inflammasome in the progression of HCC and its mechanism of action in anticancer therapy， and it is believed that NLRP3 inflammasome can be used as an effective therapeutic target for HCC patients.

Effect of Dendrobium officinale leaf fermentation fluid on a mouse model of alcoholic hepatitis and its mechanism of action / 临床肝胆病杂志

ObjectiveTo investigate the intervention mechanism of Dendrobium officinale leaf fermentation fluid in mice with alcoholic hepatitis. MethodsA total of 70 healthy male C57BL/6J mice， aged 6-8 weeks， were randomly divided into normal group， model group， liquid feed control group， silybin group， and low-， middle-， and high-dose Dendrobium officinale leaf fermentation fluid groups， with 10 mice in each group. The mice in the normal group were given normal diet， and those in the other groups were given Lieber-DeCarli classic liquid diet for 8 weeks to induce alcoholic hepatitis. During modeling， the mice in the low-， middle-， and high-dose Dendrobium officinale leaf fermentation fluid groups were given Dendrobium liquid manufactured by Warmen Pharmaceutical， and the mice in all the other groups were given pure water； the mice in the normal group， the model group， and the liquid feed control group were given normal saline by gavage， those in the silybin group were given silybin 0.25 mL/10 g by gavage， and those in the low-， middle-， and high-dose Dendrobium officinale leaf fermentation fluid groups were given Dendrobium officinale leaf fermentation fluid at a dose of 0.125 mL/10 g， 0.250 mL/10 g， and 0.375 mL/10 g， respectively， by gavage， once a day. At week 8， chloral hydrate was injected intraperitoneally for anesthesia， and blood samples were collected from the eyeball. After serum was separated， the biochemical method was used to measure the levels of aspartate aminotransferase （AST） and alanine aminotransferase （ALT）； HE staining and oil red staining were used to observe liver histopathology and lipid accumulation in mice； multiplex Luminex assay was used to measure the serum levels of interleukin-6 （IL-6）， interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， and CCL2； quantitative real-time PCR， Western blot， and immunofluorescence assay were used to measure the protein expression levels of NLRP3， caspase-1， caspase-11， gasdermin D （GSDMD）， N-terminal gasdermin D （GSDMD-N） in liver tissue. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the normal group， the model group had significant increases in the serum levels of AST， ALT， IL-6， IL-1β， TNF-α， and CCL2 （all P<0.05）， and compared with the model group， the high-dose Dendrobium officinale leaf fermentation fluid group had significant reductions in the serum levels of AST， ALT， IL-6， IL-1β， TNF-α， and CCL2 （all P<0.05）. HE staining showed that the model group had disordered structure of hepatic lobules， with a large number of steatosis vacuoles and massive cell necrosis， and compared with the model group， the high-dose Dendrobium officinale leaf fermentation fluid group had alleviation of liver histopathological injury， intact structure of most hepatic lobules， and a small amount of inflammatory cell infiltration. Oil red staining showed that the model group had accumulation of large and small lipid droplets in the liver and a significant increase in liver fat content， and compared with the model group， the high-dose Dendrobium officinale leaf fermentation fluid group had significant alleviation of hepatic steatosis， with the presence of sporadic small lipid droplets. Immunofluorescence assay of liver tissue showed that compared with the normal group， the model group had a significant increase in the ratio of GSDMD-positive staining area in hepatocyte cytoplasm （P<0.001）， and compared with the model group， the high-dose Dendrobium officinale leaf fermentation fluid group had a significant reduction in such ratio in hepatocyte cytoplasm （P<0.001）. Quantitative real-time PCR showed that compared with the normal group， the model group had significant increases in the protein expression levels of NLRP3， caspase-1， caspase-11， GSDMD， GSDMD-N， interleukin-18 （IL-18）， and IL-1β in liver tissue （all P<0.05）， and compared with the model group， the high-dose Dendrobium officinale leaf fermentation fluid group had significant reductions in the protein expression levels of NLRP3， caspase-1， caspase-11， GSDMD， GSDMD-N， IL-18， and IL-1 （all P<0.05）. Compared with the model group， the high-dose Dendrobium officinale leaf fermentation fluid group had significant reductions in the protein expression levels of caspase-1 and caspase-11 （both P<0.05）， with a relative expression level of caspase-1 of 1.757 （reduced by 26.6% compared with the model group） and a relative expression level of caspase-11 of 0.455 （reduced by 70.3% compared with the model group）， suggesting that caspase-11 showed a greater reduction than caspase-1. ConclusionDendrobium officinale leaf fermentation fluid can alleviate alcoholic hepatitis in mice， possibly by inhibiting the non-classical cell pyroptosis pathway mediated by caspase-11.

Mechanism of Traditional Chinese Medicine Intervening in Pyroptosis to Prevent and Treat Bone and Joint Related Diseases： A Review / 中国实验方剂学杂志

Osteoarthritis （OA）， rheumatoid arthritis （RA）， gouty arthritis （GA）， and intervertebral disc degeneration （IVDD） are the most common bone and joint-related diseases in clinical practice. They can all affect related joints， leading to joint pain， swelling， dysfunction， and other symptoms. The difference is that OA is mainly caused by joint wear and age-related degradation and is manifested as joint pain， stiffness， and limited movement. RA is an autoimmune disease， manifested as joint pain， swelling， morning stiffness， and systemic symptoms. GA is caused by abnormal uric acid metabolism， manifested as acute arthritis， and IVDD is caused by intervertebral disc degeneration. Studies have shown that the mechanism of the occurrence and development of these bone and joint diseases is extremely complex. Pyroptosis is closely related to these bone and joint-related diseases by participating in bone and joint inflammation， cartilage metabolism imbalance， extracellular matrix degradation， and pathological damage of bone and joint. Inhibition of bone and joint-related pyroptosis will effectively prevent and treat bone and joint-related diseases. At the same time， many studies have confirmed that traditional Chinese medicine （TCM） has a prominent curative effect and obvious advantages in the prevention and treatment of bone and joint-related diseases. TCM can reduce the inflammatory reaction of bone and joints， improve the pathological damage of bone and joint diseases， and relieve bone and joint pain by inhibiting pyroptosis. Therefore， this article aims to briefly explain the relationship between pyroptosis and the occurrence and development of bone and joint-related diseases and summarize the latest research reports on the intervention of pyroptosis in the treatment of bone and joint-related diseases by TCM monomers， TCM extracts， and TCM compounds. It offers new ideas for the in-depth study of the pathogenesis and drug treatment of bone and joint diseases and provides a basis for the clinical use of TCM to prevent and treat bone and joint diseases.

The Effect of Shenqi Jianxin Formula （参芪健心方） on Cardiomyocyte Pyroptosis in Chronic Heart Failure Model Rats Based on the NLRP3/Caspase-1 Signaling Pathway / 中医杂志

ObjectiveTo investigate the possible mechanism of Shenqi Jianxin Formula （参芪健心方） in the treatment of chronic heart failure （CHF） from the perspective of pyroptosis. MethodsFifty-two rats were randomly divided into sham operation group （n=8） and modeling group （n=44）. In the modeling group， the anterior descending branch of the left coronary artery was ligated to construct CHF rat model. Forty successfully-modelled rats were randomly divided into model group， Entresto group， Shenqi Jianxin Formula group， MCC950 group and the combination group （Shenqi Jianxin Formula plus MCC950）， with 8 rats in each group. In Shenqi Jianxin Formula group， 7.4 g/（kg·d） of Shenqi Jianxin Formula was given by gavage， while in Entresto group， 68 mg/（kg·d） of Entresto suspension was given by gavage； in MCC950 group， MCC950 was injected intraperitoneally with 10 mg/kg once every other day， and in the combination group， 7.4 g/（kg·d） of Shenqi Jianxin Formula was given by gavage， and MCC950 was injected intraperitoneally with 10 mg/kg once every other day； 10 ml/（kg·d） of saline was given by gavage in the sham operation group and the model group. After 3 weeks of continuous intervention， serum brain B-type natriuretic peptide （BNP）， creatine kinase isoenzyme MB （CK-MB）， interleukin 1β （IL-1β）， and interleukin 18 （IL-18） levels were detected by ELISA； HE staining and MASSON staining were used to observe pathological changes in rat myocardium. Except for the Entresto group， western blot technique was used to detect the expression of NOD-like receptor protein 3 （NLRP3）， caspase-1， and apoptosis-associated speck-like protein possessing a caspase-recruiting domain （ASC）； RT-PCR was used to detect the expression of NLRP3 and caspase-1 mRNA. ResultsCompared with the sham operation group， HE staining of rats in the model group showed obvious myocardial injury， while MASSON staining showed increased area of collagen fibrosis， and serum BNP， CK-MB， IL-1β， IL-18， myocardial tissue NLRP3， caspase-1， ASC protein expression and NLRP3， caspase-1 mRNA expression were all elevated （P＜0.05）. Compared with those in the model group， cardiomyocyte injury of rats and collagen fibrosis area were reduced， and serum BNP， CK-MB， IL-1β， and IL-18 contents were all reduced in Shenqi Jianxin Formula group， Entresto group， MCC950 group， and the combination group； except for Entresto group， myocardial tissue NLRP3， caspase-1， ASC protein expression and NLRP3， caspase-1 mRNA expression were reduced in the remaining three medication group （P＜0.05）. Compared with Shenqi Jianxin Formula group， the MCC950 group and the combination group showed decreased serum IL-1β and IL-18 content， collagen fibrosis area， myocardial tissue NLPR3， caspase-1 protein expression， and caspase-1 mRNA expression， and decreased ASC and NLRP3 mRNA expression was shown in the combination group （P＜0.05）. Compared with MCC950 group， collagen fibrosis area was reduced， and serum IL-18 content， NLRP3， caspase-1 mRNA expression were reduced in the combination group （P＜0.05）. ConclusionShenqi Jianxin Formula can effectively improve the myocardial injury and heart failure in rats with CHF， and its mechanism may be related to the inhibition of cardiomyocyte pyroptosis through NLPR3/Caspase-1 pathway to reduce the level of intramyocardial inflammation. The combined use of MCC950 with Shenqi Jianxin Formula could more effectively inhibite myocardial pyroptosis， with better therapeutic result than single use of each part.

Effect of Salvianolic Acid B Combined with Puerarin on Pyroptosis of SH-SY5Y Cells Injured by Oxygen-glucose Deprivation/Reoxygenation / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of salvianolic acid B combined with puerarin in protecting the SH-SY5Y cells from the damage by oxygen-glucose deprivation/reoxygenation （OGD/R） based on pyroptosis. MethodSH-SY5Y cells were used to establish the model of OGD/R， and cells were classified into the control， OGD/R， 10 μmol·L-1 salvianolic acid B， 100 μmol·L-1 puerarin， 10 μmol·L-1 salvianolic acid B + 100 μmol·L-1 puerarin， and 10 μmol·L-1 NOD-like receptor protein 3 （NLRP3） inhibitor MCC950 groups. Except the control group， other groups were rapidly reoxygenated for 12 h after 6 h OGD for modeling. The cell survival rate was determined by the methyl thiazolyl tetrazolium （MTT） assay. An optical microscope was used to observe the cell morphology. A spectrophotometer was used to determine the content of lactic dehydrogenase （LDH） in culture supernatant. Cell damage was measured by Hoechst/PI staining. The mRNA levels of NLRP3， cysteinyl aspartate specific proteinase-1 （Caspase-1）， gasdermin D （GSDMD）， apoptosis-associated speck-like protein （ASC）， and interleukin-1β （IL-1β） were determined by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The protein activation of Caspase-1 and NLRP3 was detected by immunofluorescence. Western blot was employed to determine the protein levels of IL-1β， ASC， NLRP3， Caspase-1， and cleaved Caspase-1. ResultCompared with the control group， the OGD/R group showed decreased cell survival rate （P<0.01）， damaged cell morphology， increased leakage rate of LDH （P<0.01）， up-regulated mRNA levels of NLRP3， Caspase-1， GSDMD， ASC， and IL-1β （P<0.01）， and up-regulated protein levels of IL-1β， ASC， NLRP3， Caspase-1， and cleaved Caspase-1 （P<0.01）. Compared with the OGD/R group， salvianolic acid B， puerarin， and salvianolic acid B combined with puerarin improved cell survival rate （P<0.01）， and the combined treatment group outperformed salvianolic acid B and puerarin used alone （P<0.01）. Salvianolic acid B combined with puerarin and MCC950 both improved cell morphology， reduced the leakage of LDH （P<0.01）， alleviated cell damage， and down-regulated the mRNA levels of NLRP3， Caspase-1， GSDMD， ASC， and IL-1β （P<0.05， P<0.01） and also the protein levels of IL-1β， ASC， NLRP3， Caspase-1， and cleaved Caspase-1 （P<0.05， P<0.01）. ConclusionThe results indicated that salvianolic acid B combined with puerarin can alleviate the OGD/R-induced damage of SH-SY5Y cells by inhibiting pyroptosis.

Acidic Environment Induces Pyroptosis of NLRP3 Inflammatory Vesicle-Mediated Nucleus Pulposus Cells Through Up-Regulation of POSTN Expression

SUMMARY: Intervertebral disc degeneration (IVDD) is induced by nucleus pulposus (NP) dysfunction as a result of massive loss of NP cells. It has been reported that the acidic microenvironment of the intervertebral disc (IVD) can induce NP cell pyroptosis, and that up-regulation of periostin (POSTN) expression has a negative effect on NP cell survival. However, the relationship between the acidic environment, POSTN expression level and NP cell pyroptosis is unclear. Therefore, the aim of this study was to explore the relationship between acidic environment and POSTN expression level in NP cells, as well as the effect of POSTN in acidic environment on NP cell pyroptosis. NP cells were obtained from the lumbar vertebrae of Sprague Dawley (SD) male rats. These cells were divided into normal and acidic groups according to whether they were exposed to 6 mM lactic acid solution. And NP cells in the acidic group were additionally divided into three groups: (1) Blank group: no transfection; (2) NC group: cells transfected with empty vector plasmid; (3) sh-POSTN group: cells transfected with sh-POSTN plasmid to knock down the expression level of POSTN. Quantitative real-time PCR (qRT-PCR) and western blot was performed to assess the expression of POSTN at the mRNAand protein levels. CCK8 was used to evaluate cell survival. Western blot, in addition, was performed to examine acid-sensing ion channels (ASIC)-related proteins. And pyroptosis was detected by ELISA and western blot. The expression level of POSTN was significantly increased in NP cells in acidic environment. Knockdown of POSTN expression promoted the survival of NP cells in acidic environment and reduced the protein levels of ASIC3 and ASIC1a in NP cells. Moreover, knockdown of POSTN expression decreased the pyroptosis proportion of NP cells and the levels of pro-inflammatory cytokines interleukin (IL)-1β and IL-18. The levels of pyroptosis-related proteins NLRP3, ASC, cleaved-Caspase-1, and cleaved-GSDMD were also affected by the decreased POSTN expression. The extracellular acidic environment created by lactic acid solution activated NLRP3 inflammatory vesicle-induced caspase-1 to get involved in NP cell pyroptosis by up-regulating POSTN expression.

La degeneración del disco intervertebral (DDIV) es inducida por una disfunción del núcleo pulposo (NP) como resultado de una pérdida masiva de células NP. Se ha informado que el microambiente ácido del disco intervertebral (DIV) puede inducir la piroptosis de las células NP y que la regulación positiva de la expresión de periostina (POSTN) tiene un efecto negativo en la supervivencia de las células NP. Sin embargo, la relación entre el ambiente ácido, el nivel de expresión de POSTN y la piroptosis de las células NP es poco clara. Por lo tanto, el objetivo de este estudio fue explorar la relación entre el ambiente ácido y el nivel de expresión de POSTN en células NP, así como el efecto de POSTN en ambiente ácido sobre la piroptosis de las células NP. Las células NP se obtuvieron de las vertebras lumbares de ratas macho Sprague Dawley (SD). Estas células se dividieron en grupos normales y ácidos según se expusieron a una solución de ácido láctico 6 mM. Las células NP en el grupo ácido se dividieron adicionalmente en tres grupos: (1) Grupo en blanco: sin transfección; (2) grupo NC: células transfectadas con plásmido vector vacío; (3) grupo sh-POSTN: células transfectadas con plásmido sh-POSTN para reducir el nivel de expresión de POSTN. Se realizó una PCR cuantitativa en tiempo real (qRT-PCR) y una transferencia Western para evaluar la expresión de POSTN en los niveles de ARNm y proteína. Se utilizó CCK8 para evaluar la supervivencia celular. Además, se realizó una transferencia Western para examinar las proteínas relacionadas con los canales iónicos sensibles al ácido (ASIC). La piroptosis se detectó mediante ELISA y Western blot. El nivel de expresión de POSTN aumentó significativamente en células NP en ambiente ácido. La eliminación de la expresión de POSTN promovió la supervivencia de las células NP en un ambiente ácido y redujo los niveles de proteína de ASIC3 y ASIC1a en las células NP. Además, la eliminación de la expresión de POSTN disminuyó la proporción de piroptosis de las células NP y los niveles de citocinas proinflamatorias interleucina (IL) - 1β e IL-18. Los niveles de proteínas relacionadas con la piroptosis NLRP3, ASC, Caspasa-1 escindida y GSDMD escindida también se vieron afectados por la disminución de la expresión de POSTN. El ambiente ácido extracelular creado por la solución de ácido láctico activó la caspasa-1 inducida por vesículas inflamatorias NLRP3 para involucrarse en la piroptosis de las células NP mediante la regulación positiva de la expresión de POSTN.

Puerarin protects renal ischemia-reperfusion injury in rats through NLRP3/Caspase-1/GSDMD pathway

Purpose: To observe the effect of puerarin on renal ischemia-reperfusion (I/R) injury in rats, and to explore its mechanism based on NLRP3/Caspase-1/GSDMD pathway. Methods: Twenty-one Sprague-Dawley rats were divided into three groups: sham-operated group (sham), model group (RIRI), and puerarin treatment group (RIRI + Pue). The model of acute renal I/R injury was established by cutting the right kidney and clamping the left renal pedicle for 45 min. Results: Renal function parameters were statistically significant in group comparisons. The renal tissue structure of rats in sham group was basically normal. Pathological changes were observed in the RIRI group. The renal pathological damage score and apoptosis rate in the RIRI group were higher than those in the sham group, and significantly lower in the RIRI + Pue group than in the RIRI group. Indicators of oxidative stress-superoxide dismutase, malondialdehyde, and glutathione peroxidase-were statistically significant in group comparisons. Compared with the sham group, the relative expressions of NLRP3, Caspase-1 and GSDMD proteins in the RIRI group were increased. Compared with the RIRI group, the RIRI + Pue group had significant reductions. Conclusions: Puerarin can inhibit the activation of NLRP3/Caspase-1/GSDMD pathway, inhibit inflammatory response and pyroptosis, and enhance the antioxidant capacity of kidney, thereby protecting renal I/R injury in rats.

Mechanism underlying Müller cell pyroptosis and its role in the development of proliferative vitreoretinopathy

Abstract Objectives To explore the mechanism underlying Müller Cell Pyroptosis (MCP) and its role in the development of Proliferative Vitreoretinopathy (PVR). Method The expression of pyroptosis-related factors, namely, cysteinyl aspartate-specific proteinase (caspase-1), interleukin (IL)-1β, IL-18, and Gasdermin D (GSDMD), was detected by quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) and western blotting at the mRNA and protein levels, respectively, in retinal tissues. Müller and spontaneously Arising Retinal Pigment Epithelia (ARPE)-19 primary cells with GSDMD overexpression or knockdown were cultivated. Western blotting was used to detect the levels of the following pyroptosis-related factors in retinal tissues: caspase-1, IL-1β, IL-18, and GSDMD. Through Cell Adhesion (CA) experiments, the changes in ARPE-19 CA in each group were observed. The migration and invasion of ARPE-19 cells were measured using the Transwell assay. The proliferation of ARPE-19 cells was measured with a Cell Counting Kit 8 (CCK-8) assay. Finally, the expression of the cytokines IL-1β and IL-18 in the ARPE-19 cell culture medium was detected using the Enzyme-Linked Immunosorbent Assay (ELISA). Results Compared with the surrounding normal tissues, the expression of caspase-1, IL-1β, IL-18, and GSDMD at the protein and mRNA levels in the retinal proliferative membrane samples of the patients decreased significantly (p < 0.05). MCP significantly enhanced ARPE-19 CA, migration and invasion, proliferation, and cytokine expression (p < 0.05). Conclusions MCP can promote the development of PVR lesions.

Alpha-kinase1 promotes tubular injury and interstitial inflammation in diabetic nephropathy by canonical pyroptosis pathway

BACKGROUND: Alpha-kinase 1 (ALPK1) is a master regulator in inflammation and has been proved to promote renal fibrosis by promoting the production of IL-1ß in diabetic nephropathy (DN) mice. Pyroptosis is involved in high glucose (HG)-induced tubular cells injury, characterized by activation of Gasdermin D (GSDMD) and the release of IL-1ß and IL-18, resulting in inflammatory injury in DN. It is reasonable to assume that ALPK1 is involved in pyroptosis-related tubular injury in DN. However, the mechanism remains poorly defined. METHODS: Immunohistochemistry (IHC) staining was performed to detect the expression of pyroptosis- and fibrosis-related proteins in renal sections of DN patients and DN mice. DN models were induced through injection of streptozotocin combined with a high-fat diet. Protein levels of ALPK1, NF-κB, Caspase-1, GSDMD, IL-1ß, IL-18 and α-SMA were detected by Western blot. HK-2 cells treated with high-glucose (HG) served as an in vitro model. ALPK1 small interfering RNA (siRNA) was transfected into HK-2 cells to down-regulate ALPK1. The pyroptosis rates were determined by flow cytometry. The concentrations of IL-1ß and IL-18 were evaluated by ELISA kits. Immunofluorescence staining was used to observe translocation of NF-κB and GSDMD. RESULTS: The heat map of differentially expressed genes showed that ALPK1, Caspase-1 and GSDMD were upregulated in the DN group. The expression levels of ALPK1, Caspase-1, GSDMD and CD68 were increased in renal biopsy tissues of DN patients by IHC. ALPK1expression and CD68+ macrophages were positively correlated with tubular injury in DN patients. Western blot analysis showed increased expressions of ALPK1, phospho-NF-κB P65, GSDMD-NT, and IL-1ß in renal tissues of DN mice and HK-2 cells, accompanied with increased renal fibrosis-related proteins (FN, α-SMA) and macrophages infiltration in interstitial areas. Inhibition of ALPK1 attenuated HG-induced upregulation expressions of NF-κB, pyroptosis-related proteins Caspase-1, GSDMD-NT, IL-1ß, IL-18, α-SMA, and pyroptosis level in HK-2 cells. Also, the intensity and nuclear translocation of NF-κB and membranous translocation of GSDMD were ameliorated in HG-treated HK-2 cells after treatment with ALPK1 siRNA. CONCLUSIONS: Our data suggest that ALPK1/NF-κB pathway initiated canonical caspase-1-GSDMD pyroptosis pathway, resulting in tubular injury and interstitial inflammation of DN.

Effect of procalcitonin on lipopolysaccharide-induced expression of nucleotide-binding oligomerization domain-like receptor protein 3 and caspase-1 in human umbilical vein endothelial cells / 中国当代儿科杂志

OBJECTIVES@#To study the effect of procalcitonin (PCT) on lipopolysaccharide (LPS)-induced expression of the pyroptosis-related proteins nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) and caspase-1 in human umbilical vein endothelial cells (HUVECs).@*METHODS@#HUVECs were induced by LPS to establish a model of sepsis-induced inflammatory endothelial cell injury. The experiment was divided into two parts. In the first part, HUVECs were randomly divided into four groups: normal control, LPS (1 μg/mL), PCT (10 ng/mL), and LPS+PCT (n=3 each). In the second part, HUVECs were randomly grouped: normal control, LPS, and LPS+PCT of different concentrations (0.1, 1, 10, and 100 ng/mL) (n=3 each). Quantitative real-time PCR and Western blot were used to measure the mRNA and protein expression levels of NLRP3 and caspase-1 in each group.@*RESULTS@#In the first experiment: compared with the normal control group, the PCT, LPS, and LPS+PCT groups had significantly upregulated mRNA and protein expression levels of NLRP3 and caspase-1 (P<0.05); compared with the LPS group, the LPS+PCT group had significantly downregulated mRNA and protein expression levels of NLRP3 and caspase-1 (P<0.05). In the second experiment: compared with those in the LPS group, the mRNA and protein expression levels of NLRP3 and caspase-1 in the LPS+PCT of different concentrations groups were significantly downregulated in a concentration-dependent manner (P<0.05).@*CONCLUSIONS@#LPS can promote the expression of the pyroptosis-related proteins NLRP3 and caspase-1 in HUVECs, while PCT can inhibit the LPS-induced expression of the pyroptosis-related proteins NLRP3 and caspase-1 in HUVECs in a concentration-dependent manner.

Anti-glioma mechanism of pterostilbene by regulating apoptosis and GSDME-mediated pyroptosis pathways: a study based on network pharmacology and experimental research / 中国中药杂志

This study aimed to explore the anti-glioma effect of natural compound pterostilbene(PTE) through regulating pyroptosis and apoptosis pathways, and to analyze the possible anti-glioma pathways and targets of PTE by network pharmacology and molecular docking. In this study, the action targets of PTE and the glioma targets were obtained by network pharmacology to construct a target network and a protein-protein interaction(PPI) network to predict the possible action targets of PTE against glioma. Molecular docking was performed on the core targets by AutoDock and the action pathways of PTE against glioma were predicted by enrichment analysis. In addition, the effect of PTE on the viability of U87MG and GL261 glioma cells was detected by CCK-8 assay. Clone formation assay and cell scratching assay were used to explore the effect of different concentrations of PTE on the proliferation and migration, respectively of glioma cells. Hoechst staining was used to observe PTE-induced apoptosis in glioma cells. The changes in mitochondrial membrane potential were detected by JC-1 staining. The pyroptosis-inducing effect of PTE on glioma cells was observed by inverted microscopy and lactate dehydrogenase(LDH) assay. Hoechst 33342/PI dual staining assay was performed to detect the integrity of glioma cell membranes. The expressions of pyroptosis and apoptosis-related proteins in glioma cells after PTE induction were determined by Western blot. In this study, 37 anti-glioma targets of PTE were obtained, and enrichment analysis suggested that PTE exerted anti-glioma effects through various signaling pathways including cancer pathway, proteoglycan in cancer, PI3K/AKT pathway, and apoptosis regulatory pathway. Molecular docking revealed that PTE had good binding activity with the main targets. Compared with the control group, PTE significantly reduced the viability as well as the proliferation, migration and adhesion abilities of U87MG and GL261 cells; it induced the apoptosis of the two glioma cells and the decrease of mitochondrial membrane potential in U87MG cells, and the effects increased with the increase of drug concentration. Compared with the conditions in the control group, glioma cells in the PTE group had increased pyroptosis-specific appearance and gradually increased LDH release; the number of PI positive cells was significantly elevated with the increase of PTE concentration as revealed by Hoechst 33342/PI staining; the expression levels of apoptosis-related factors cleaved PARP1 and B-cell lymphoma-2(Bcl-2) associated X(BAX) in the PTE group were markedly up-regulated, while the expression level of Bcl-2 was markedly down-regulated; the activation levels of pyroptosis-related proteins cleaved caspase-3 and gasdermin E-N(GSDME-N) had a remarkable rise in the PTE group, while no significant changes were found in the activation levels of gasdermin D-N(GSDMD-N) and cleaved caspase-1. In summary, PTE plays an anti-glioma role by inhibiting cell viability, proliferation, and migration and activating the caspase-3/GSDME-mediated pyroptosis pathway and mitochondrial apoptosis pathway.

Effect of Gualou Xiebai Decoction on pulmonary fibrosis in rats based on pyroptosis pathway / 中国中药杂志

This study investigated the effect of Gualou Xiebai Decoction on rats with bleomycin-induced pulmonary fibrosis. The rats were randomly divided into a control group, a model group, a low-dose Gualou Xiebai Decoction group(2.4 g·kg~(-1)), a high-dose Gualou Xiebai Decoction group(4.8 g·kg~(-1)), and pirfenidone group(150 mg·kg~(-1)). The model of pulmonary fibrosis was established by intratracheal instillation of bleomycin in all groups, except the control group. Since the second day of modeling, the corresponding drugs were given to rats by intragastric administration, once a day for 14 d and 28 d. The hematoxylin-eosin(HE) staining was used to evaluate the degree of inflammatory injury in lung tissues. The immunofluorescence staining was used to detect the expression of CD68 and CD163 in lung tissues of rats. The levels of tumor necrosis factor-α(TNF-α) and interleukin-10(IL-10) in serum and brochoalveolar lavage fluid(BALF) were detected by enzyme-linked immunosorbent assay(ELISA). The expression of pyroptosis-related genes in lung tissues of rats was detected by qRT-PCR. The results of HE staining and immunofluorescence staining showed that the lung tissue structure was normal in the control group. In addition, there were alveolar collapse or even closure in lung tissues of rats in the model group, with obvious inflammatory cell infiltration, and the expression of CD68 and CD163 was significantly up-regulated. As compared with the model group, the lung tissue structure of rats in the Gualou Xiebai Decoction groups was significantly improved, with alleviated inflammation, and the expression of CD68 and CD163 was decreased. As compared with the control group, the level of TNF-α in serum and BALF of rats in the model group was significantly increased(P<0.01), the mRNA expression levels of alpha smooth muscle actin(α-SMA), collagen type Ⅰ alpha 1 chain(Col1a1), caspase-1, IL-1β, IL-18, gasdermin D(Gsdmd), and NOD-like receptor thermal protein domain associated protein 3(NLRP3) in lung tissues were significantly increased(P<0.05, P<0.01), and the mRNA expression level of E-cadherin was significantly decreased(P<0.01). As compared with the model group, the level of TNF-α in serum and BALF was significantly down-regulated in the high-dose Gualou Xiebai Decoction group(P<0.05, P<0.01), and that of IL-10 was up-regulated(P<0.05, P<0.01). The mRNA expression levels of α-SMA, Col1a1, caspase-1, IL-18, Gsdmd, NLRP3 and IL-1β in lung tissues were significantly decreased(P<0.05, P<0.01) in the high-dose Gualou Xiebai Decoction group, and the mRNA expression level of E-cadherin was significantly increased(P<0.05, P<0.01). In conclusion, Gualou Xiebai Decoction can down-regulate the levels of inflammatory factors and related genes and effectively mitigate pulmonary fibrosis by regulating the pyroptosis pathways.

Compound Tinglizi Decoction intervenes COPD-associated pulmonary hypertension through regulation of HMGB1-mediated pyroptosis and immune imbalance / 中国中药杂志

This paper aimed to investigate the effects of high mobility group box 1(HMGB1)-mediated pulmonary artery smooth muscle cell pyroptosis and immune imbalance on chronic obstructive pulmonary disease-associated pulmonary hypertension(COPD-PH) in rats and the intervening mechanism of Compound Tinglizi Decoction. Ninety rats were randomly divided into a normal group, a model group, low-dose, medium-dose, and high-dose Compound Tinglizi Decoction groups, and a simvastatin group. The rat model of COPD-PH was established by fumigation combined with lipopolysaccharide(LPS) intravascular infusion, which lasted 60 days. Rats in the low, medium, and high-dose Compound Tinglizi Decoction groups were given 4.93, 9.87, and 19.74 g·kg~(-1) Compound Tinglizi Decoction by gavage, respectively. Rats in the simvastatin group were given 1.50 mg·kg~(-1) simvastatin by gavage. After 14 days, the lung function, mean pulmonary artery pressure, and arterial blood gas of rats were analyzed. Lung tissues of rats were collected for hematoxylin-eosin(HE) staining to observe the pathological changes. Real-time fluorescent quantitative polymerase chain reaction(qRT-PCR) was used to determine the expression of related mRNA in lung tissues, Western blot(WB) was used to determine the expression of related proteins in lung tissues, and enzyme linked immunosorbent assay(ELISA) was used to determine the levels of inflammatory factors in the lung tissues of rats. The ultrastructure of lung cells was observed by transmission electron microscope. The forced vital capacity(FVC), forced expiratory volume in 0.3 second(FEV_(0.3)), FEV_(0.3)/FVC, peek expiratory flow(PEF), respiratory dynamic compliance(Cdyn), arterial partial pressure of oxygen(PaO_2), and arterial oxygen saturation(SaO_2) were increased, and resistance of expiration(Re), mean pulmonary arterial pressure(mPAP), right ventricular hypertrophy index(RVHI), and arterial partial pressure of carbon dioxide(PaCO_2) were decreased by Compound Tinglizi Decoction in rats with COPD-PH. Compound Tinglizi Decoction inhibited the protein expression of HMGB1, receptor for advanced glycation end products(RAGE), pro caspase-8, cleaved caspase-8, and gasdermin D(GSDMD) in lung tissues of rats with COPD-PH, as well as the mRNA expression of HMGB1, RAGE, and caspase-8. Pulmonary artery smooth muscle cell pyroptosis was inhibited by Compound Tinglizi Decoction. Interferon-γ(IFN-γ) and interleukin-17(IL-17) were reduced, and interleukin-4(IL-4) and interleukin-10(IL-10) were incresead by Compound Tinglizi Decoction in lung tissues of rats with COPD-PH. In addition, the lesion degree of trachea, alveoli, and pulmonary artery in lung tissues of rats with COPD-PH was improved by Compound Tinglizi Decoction. Compound Tinglizi Decoction had dose-dependent effects. The lung function, pulmonary artery pressure, arterial blood gas, inflammation, trachea, alveoli, and pulmonary artery disease have been improved by Compound Tinglizi Decoction, and its mechanism is related to HMGB1-mediated pulmonary artery smooth muscle cell pyroptosis and helper T cell 1(Th1)/helper T cell 2(Th2), helper T cell 17(Th17)/regulatory T cell(Treg) imbalance.

Relationship between pyroptosis and cardiovascular diseases and traditional Chinese medicine prevention and treatment research / 中国中药杂志

Pyroptosis is a programmed cell death initiated by the activation of caspases, which is involved in the development and progression of several cardiovascular diseases. The gasdermins, a protein family, are key executive proteins in the development of pyroptosis, which increase cell membrane permeability, mediate the release of inflammatory factors, and aggravate the inflammatory injury. Traditional Chinese medicine(TCM)has shown unique therapeutic advantages in cardiovascular diseases with multi-component and multi-target characteristics. Currently, the effective prevention and treatment of cardiovascular diseases based on the theory of pyroptosis become a new research hotspot in this field. Based on the theories of TCM and modern medicine, this study summarized the role of pyroptosis in cardiovascular diseases such as atherosclerosis, myocardial infarction, diabetic cardiomyopathy, hypertension, and myocarditis. The role of TCM, including active monomers, crude extracts, and compound preparations, in cardiovascular protection through the regulation of pyroptosis was also summarized, providing a theoretical basis for the clinical prevention and treatment of cardiovascular diseases by TCM.

Effect of multi-glycosides of Tripterygium wilfordii on renal injury in diabetic kidney disease rats through NLRP3/caspase-1/GSDMD pyroptosis pathway / 中国中药杂志

This study investigated the effect of multi-glycosides of Tripterygium wilfordii(GTW) on renal injury in diabetic kidney disease(DKD) rats through Nod-like receptor protein 3(NLRP3)/cysteine-aspartic acid protease-1(caspase-1)/gsdermin D(GSDMD) pyroptosis pathway and the mechanism. To be specific, a total of 40 male SD rats were randomized into the normal group(n=8) and modeling group(n=34). In the modeling group, a high-sugar and high-fat diet and one-time intraperitoneal injection of streptozotocin(STZ) were used to induce DKD in rats. After successful modeling, they were randomly classified into model group, valsartan(Diovan) group, and GTW group. Normal group and model group were given normal saline, and the valsartan group and GTW group received(ig) valsartan and GTW, respectively, for 6 weeks. Blood urea nitrogen(BUN), serum creatinine(Scr), alanine ami-notransferase(ALT), albumin(ALB), and 24 hours urinary total protein(24 h-UTP) were determined by biochemical tests. The pathological changes of renal tissue were observed based on hematoxylin and eosin(HE) staining. Serum levels of interleukin-1β(IL-1β) and interleukin-18(IL-18) were detected by enzyme-linked immunosorbent assay(ELISA). Western blot was used to detect the expression of pyroptosis pathway-related proteins in renal tissue, and RT-PCR to determine the expression of pyroptosis pathway-related genes in renal tissue. Compared with the normal group, the model group showed high levels of BUN, Scr, ALT, and 24 h-UTP and serum levels of IL-1β and IL-18(P<0.01), low level of ALB(P<0.01), severe pathological damage to kidney, and high protein and mRNA levels of NLRP3, caspase-1, and GSDMD in renal tissue(P<0.01). Compared with the model group, valsartan group and GTW group had low levels of BUN, Scr, ALT, and 24 h-UTP and serum levels of IL-1β and IL-18(P<0.01), high level of ALB(P<0.01), alleviation of the pathological damage to the kidney, and low protein and mRNA levels of NLRP3, caspase-1, and GSDMD in renal tissue(P<0.01 or P<0.05). GTW may inhibit pyroptosis by decreasing the expression of NLRP3/caspase-1/GSDMD in renal tissue, thereby relieving the inflammatory response of DKD rats and the pathological injury of kidney.