L-AP Alleviates Liver Injury in Septic Mice by Inhibiting Macrophage Activation via Suppressing NF-κB and NLRP3 Inflammasome/Caspase-1 Signal Pathways.

Liver injury and progressive liver failure are severe life-threatening complications in sepsis, further worsening the disease and leading to death. Macrophages and their mediated inflammatory cytokine storm are critical regulators in the occurrence and progression of liver injury in sepsis, for which effective treatments are still lacking. l-Ascorbic acid 6-palmitate (L-AP), a food additive, can inhibit neuroinflammation by modulating the phenotype of the microglia, but its pharmacological action in septic liver damage has not been fully explored. We aimed to investigate L-AP's antisepticemia action and the possible pharmacological mechanisms in attenuating septic liver damage by modulating macrophage function. We observed that L-AP treatment significantly increased survival in cecal ligation and puncture-induced WT mice and attenuated hepatic inflammatory injury, including the histopathology of the liver tissues, hepatocyte apoptosis, and the liver enzyme levels in plasma, which were comparable to NLRP3-deficiency in septic mice. L-AP supplementation significantly attenuated the excessive inflammatory response in hepatic tissues of septic mice in vivo and in cultured macrophages challenged by both LPS and ATP in vitro, by reducing the levels of NLRP3, pro-IL-1ß, and pro-IL-18 mRNA expression, as well as the levels of proteins for p-I-κB-α, p-NF-κB-p65, NLRP3, cleaved-caspase-1, IL-1ß, and IL-18. Additionally, it impaired the inflammasome ASC spot activation and reduced the inflammatory factor contents, including IL-1ß and IL-18 in plasma/cultured superannuants. It also prevented the infiltration/migration of macrophages and their M1-like inflammatory polarization while improving their M2-like polarization. Overall, our findings revealed that L-AP protected against sepsis by reducing macrophage activation and inflammatory cytokine production by suppressing their activation in NF-κB and NLRP3 inflammasome signal pathways in septic liver.

Effect of electroacupuncture on Nrf2/NLRP3/Caspase-1 pathway mediated-pyroptosis in mice with Parkinson's disease. / ç”µé’ˆå¯¹å¸•é‡‘æ£®ç— å°é¼ Nrf2/NLRP3/Caspase-1通路介导的细胞焦亡的影响.

OBJECTIVES: To observe the effect of electroacupuncture (EA) on nuclear transcription factor E2 related factor 2 (Nrf2)/NOD-like receptor family pyrin domain-containing protein 3 (NLRP3)/cysteine aspartic acid specific protease-1 (Caspase-1) pathway in the substantia nigra (SN) of mice with Parkinson's disease (PD), so as to explore the neuroprotective mechanism of EA. METHODS: Forty C57BL/6 male mice were randomly divided into 4 groups, namely, control, PD model, EA and sham-EA groups, with 10 mice in each group. The PD mouse model was established by gavage of rotenone for 4 weeks. Mice in the EA group were given EA stimulation (1 mA, 2 Hz) at "Fengfu" (GV36), bilateral "Taichong" (LR3) and "Zusanli" (ST36) for 30 min, once daily for 2 consecutive weeks. And mice in the sham-EA group were given acupuncture at the subcutaneous areas of the same acupoints without EA stimulation. The open-field test was used for assessment of mouse behavior. The levels of interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) in the serum were detected by enzyme-linked immunosorbent assay . The positive expression of tyrosine hydroxylase (TH) in SN was determined by immunohistochemistry. The mRNA expression levels of Nrf2, NLRP3, Caspase-1, gasdermin D(GSDMD), IL-1ß, IL-18 and the protein expression levels of Nrf2, NLRP3, Caspase-1 and GSDMD in the SN were detected by quantitative real-time PCR and Western blot, separately. RESULTS: After modeling, compared with the control group, the behavioral score was increased (P<0.01), the total exercise time, the total distance and the average speed were decreased (P<0.01), and the positive expression of TH and the mRNA and protein expression levels of Nrf2 in the SN were decreased (P<0.01), while the contents of IL-1ß and IL-18 in serum, the mRNA and protein expression levels of NLRP3, Caspase-1 and GSDMD and the mRNA expression levels of IL-1ß and IL-18 in the SN were up-regulated (P<0.01) in the PD model group. Following EA intervention, the behavioral score was decreased(P<0.01), the total exercise time, total distance and average speed were increased (P<0.01), the positive expression of TH and the mRNA and protein expressions of Nrf2 in SN were up-regulated (P<0.01, P<0.05), while the contents of IL-1ß and IL-18 in serum, the mRNA and protein expression levels of NLRP3, Caspase-1 and GSDMD as well as the mRNA expression levels of IL-1ß and IL-18 in the SN were down-regulated (P<0.01, P<0.05) in the EA group relative to the PD model and sham-EA groups. There were no significant differences in the above indicators between the PD model and sham-EA groups. CONCLUSIONS: EA stimulation of GV36, LR3 and ST36 can improve motor deficits, reduce the loss of dopamine neurons in the SN, and inhibit neuroinflammatory responses in mice with PD, which may be related to its effects in regulating the Nrf2/NLRP3/Caspase-1 pathway mediated pyroptosis.

Moxibustion intervention improves synovitis by down-regulating NLRP3/Caspase-1/IL-1ß signaling of synovial tissue in rats with adjuvant arthritis. / 基于NLRP3/Caspase-1/IL-1ßä¿¡å·é€šè·¯æŽ¢è®¨è‰¾ç¸æ”¹å–„ä½å‰‚æ€§å ³èŠ‚ç‚Žå¤§é¼ æ»‘è†œç‚Žçš„æœºåˆ¶.

OBJECTIVES: To observe the effect of moxibustion on activities of NOD-like receptor family protein 3 (NLRP3)/cysteine aspartic acid specific protease-1 (Caspase-1)/interleukin-1ß (IL-1ß) signaling pathway in rats with adjuvant arthritis (AA), so as to explore its mechanisms underlying improvement of rheumatoid arthritis (RA). Me-thods Thirty male Wistar rats were randomly divided into normal control, AA model and moxibustion groups, with 10 rats in each group. The AA model was replicated by raising in wind, cold and damp environment combined with complete Freund's adjuvant injection. In the moxibustion group, moxibustion was applied to bilateral "Shenshu" (BL23) and "Zusanli"(ST36) for 20 min each time, once daily for 21 days. Changes of joint swelling degree (JSD) and arthritis index (AI) in each group were observed. The ultrastructural changes of synovial cells in each group were observed by transmission electron microscopy. The protein expression levels of NLRP3, apoptosis-associated speck-like protein (ASC), Caspase-1, tumor necrosis factor-α (TNF-α) and IL-1ß in the synovial tissues of the knee joint were measured by Western blot. RESULTS: Compared with the normal control group, JSD, AI and the protein expressions of NLRP3, ASC, Caspase-1, TNF-α and IL-1ß in the synovial tissues were significantly increased (P<0.01) in the model group. In comparison with the model group, JSD, AI and the protein expression levels of NLRP3, ASC, Caspase-1, TNF-α and IL-1ß were significantly decreased (P<0.01) in the moxibustion group. Results of transmission electron microscope showed an irregular and vague nuclear membrane of synovial cells, and unclear mitochondrial membrane boundary with sparse, swelling crests in the model group, which was relatively milder in the damage degree in the moxibustion group. CONCLUSIONS: Moxibustion can relieve the inflammatory response in the synovial membrane of AA rats, which may be related to its function in down-regulating synovial NLRP3/Caspase-1/IL-1ß inflammatory signaling.

[Acupoint catgut embedding relieves colonic inflammatory injury by down-regulating NLRP3/Caspase-1 signaling pathway in rats with ulcerative colitis].

OBJECTIVE: To observe the effect of acupoint catgut embedding (CE) on Nod-like receptor protein 3 (NLRP3)/Caspase-1 signaling pathway in "deficiency-stasis" syndrome type ulcerative colitis (UC) rats, so as to explore its mechanisms underlying improvement of UC. METHODS: A total of 58 male SD rats were randomly divided into control group (10 rats) and model group (48 rats). The "deficiency-stasis" type UC model was established by gavage of adenine and folium sennae solution for 4 weeks, followed by clycter of mixture solution of 5% trinitro-benzene-sulfonic acid and 50% ethanol. A total of 44 UC rats were randomized into model, salicylazosulfapyridine (SASP), non-acupoint CE, and acupoint CE groups (11 rats in each group). The catgut embedment was applied to bilateral "Zusanli"(ST36), "Shenshu"(BL23), "Pishu"(BL20), "Dachangshu"(BL25), "Geshu" (BL17) and "Tianshu"(ST25), or non-acupoints (the fat muscles of the buttocks), separately, once every two weeks, 3 times altogether. Rats of the SASP group received gavage of SASP solution, and those of the other groups received gavage of same amount of normal saline, once daily for 42 days. The rat's general conditions and the colon length were recorded, the disease activity index (DAI, 0 to 4 points) and colonic mucosal damage index (CMDI, 0 to 5 points) were calculated. Histopathological changes of the colonic mucosa tissue were observed after HE staining, and the tissue damage index (TDI, 0 to 6 points) was given. The levels of serum NLRP3, interleukin (IL)-1ß and IL-18 were measured by ELISA, and the expression levels of NLRP3, Caspase-1, apoptosis-associated speck-like protein (ASC), IL-1ß and IL-18 mRNAs were measured by fluorescence quantitative PCR. The expression levels of NLRP3 and Caspase-1 proteins in the colon tissues were measured by Western blot, and the immunoactivity of colonic ASC was detected by immunohistochemistry. RESULTS: Compared with the control group, the rats' body mass and colonic length were significantly decreased (P<0.01), and DAI score, CMDI score, TDI score, contents of serum NLRP3, IL-1ß and IL-18, expression levels of colonic NLRP3, ASC, Caspase-1, IL-1ß and IL-18 mRNAs, and NLRP3 and Caspase -1 proteins as well as colonic ASC immunoactivity were significantly up-regulated in the model group (P<0.01). Compared with the model group, both SASP and acupoint CE groups had a significant increase in body mass and colonic length (P<0.01), and a marked decrease in DAI score, CMDI score, TDI score, contents of serum NLRP3, IL-1ß and IL-18, expression levels of NLRP3, ASC, Caspase-1, IL-1ß and IL-18 mRNAs and NLRP3 and Caspase-1 proteins and ASC immunoactivity (P<0.01). The above indexes were improved in the acupoint CE group in relevant to those of the non-acupoint CE group (P<0.01). HE staining of colonic mucosal tissue showed obvious ulcerative surface, destroyed recess, disordered arrangement of glands, mucosal edema and congestion, infiltration of a large number of inflammatory cells in the model group, which was obviously milder in both SASP and acupoint CE groups. CONCLUSION: Acupoint embedding can alleviate colonic injury and inhibit inflammatory reaction in rats with "deficiency-stasis" type UC by down-regulating colonic NLRP3/Caspase-1 signaling.

[Effects of electroacupuncture on NLRP3/Caspase-1/GSDMD axis and neurological function in rats with cerebral ischemic reperfusion].

OBJECTIVE: To investigate the neuroprotective effect of electroacupuncture (EA) at "Quchi" (LI 11) and "Zusanli" (ST 36) in the rats with cerebral ischemic reperfusion and the potential mechanism of microglia pyroptosis. METHODS: Sixty SD rats were randomly divided into a sham-operation group, a model group and an EA group, with 20 rats in each group. The Zea Longa method was employed to establish the rat model of the middle cerebral artery occlusion and reperfusion (MACO/R) in the left brain. In the EA group, since the 2nd day of modeling, EA was given at "Quchi" (LI 11) and "Zusanli" (ST 36) of right side with disperse-dense wave, 4 Hz/20 Hz in frequency and 0.2 mA in current intensity, 30 min each time, once a day for lasting 7 consecutive days. The reduction rate of cerebral blood flow was measured with laser Doppler flowmetry during operation. The neurological function of rats was observed using Zea Longa neurobehavioral score. The cerebral infarction volume was detected by TTC staining method. The microglia positive expression in the ischemic side of the cortex was detected with the immunofluorescence method. Under transmission electron microscope, the ultrastructure of cell in the ischemic cortex was observed. The mRNA expression levels of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), cysteinyl aspartate specific proteinase-1 (Caspase-1) and gasdermin D (GSDMD) in the ischemic cortex were detected using real-time PCR. RESULTS: Compared with the sham-operation group, in the model group, the reduction rate of cerebral blood flow was increased during operation (P<0.001); Zea Longa neurobehavional score and the percentage of cerebral infarction volume were increased (P<0.001), the numbers of M1-type microglia marked by CD68+ and M2-type microglia marked by TMEM119+ were elevated in the ischemic cortex (P<0.001), the mRNA expression of NLRP3, ASC, Caspase-1 and GSDMD was increased (P<0.001, P<0.01); the cytomembrane structure was destroyed, with more cell membrane pores formed in the ischemic cortex. Compared with the model group, after intervention, Zea Longa neurobehavioral score and the percentage of cerebral infarction volume were reduced (P<0.05), the number of M1-type microglia marked by CD68+ was reduced (P<0.05) and the number of M2-type microglia marked by TMEM119+ was increased (P<0.05); and the mRNA expression of NLRP3, ASC, Caspase-1 and GSDMD was decreased (P<0.01, P<0.05) in the EA group. Even though the cytomembrane structure was incomplete, there were less membrane pores presented in the ischemic cortex in the EA group after intervention. CONCLUSION: The intervention with EA attenuates the neurological dysfunction and reduces the volume of cerebral infarction in the rats with cerebral ischemic reperfusion. The underlying mechanism is related to the inhibition of microglia pyroptosis through modulating NLRP3/Caspase-1/GSDMD axis.

[Electroacupuncture alleviates cerebral ischemia injury in rats by regulating melatonin-NLRP3 and inhibiting pyroptosis].

OBJECTIVE: To investigate the mechanism of electroacupuncture in alleviating cerebral ischemia injury in cerebral ischemia-reperfusion rats by regulating melatonin - NOD-like receptor protein 3 (NLRP3) mediated pyroptosis. METHODS: A total of 48 SD rats were randomly divided into sham operation group, model group, electroacupuncture (EA) group and EA +Luz group, with 12 rats in each group. The focal cerebral ischemia-reperfusion injury model was established by middle cerebral artery embolization. Rats of the EA group was treated with EA stimulation (4 Hz/20 Hz, 0.5 mA,20 min) at "Baihui" (GV20) and "Shenting" (GV24) once a day for 7 consecutive days; rats of EA+Luz group were given the same EA treatment and intraperitoneally administered melatonin receptor antagonist (luzindole, 30 mg/kg), once a day for 7 consecutive days. The neurological impairment was evaluated by Zea Longa score. The level of serum melatonin content at 12:00 and 24:00 was detected by ELISA. The percentage of cerebral infarction volume was evaluated by MRI of small animals. The apoptosis rate of nerve cells in cerebral cortex of infarct side was detected by TUNEL staining. The activation of microglia cells was detected by immunofluorescence staining. The expression levels of pyroptosis-related proteins NLRP3, Caspase-1 and interleukin (IL) -1ß were detected by Western blot. RESULTS: Compared with the sham operation group, the neural function score was significantly increased (P<0.01); the melatonin content was significantly decreased at 24:00 (P<0.01); the percentage of cerebral infarction volume, apoptosis rate of nerve cells in cerebral cortex area of infarction side, the expressions of NLRP3, Caspase-1 and IL-1ß proteins were significantly increased (P<0.01); and microglia cells were significantly activated in the model group.Compared with the model and EA +Luz groups, the nerve function score was significantly decreased (P<0.05); the percentage of cerebral infarction volume, the nerve cell apoptosis rate, the activation level of microglia cells, the expression levels of NLRP3, Caspase-1 and IL-1ß were significantly decreased (P<0.01, P<0.05) in the EA group. Compared with the model and EA+Luz groups, the melatonin content at 24:00 was significantly increased (P<0.01, P<0.05) in the EA group. CONCLUSION: EA at GV20 and GV24 can reduce the neurolo-gical injury in cerebral ischemia reperfusion model rats, which may be related to regulating the expression of endogenous melatonin, inhibiting cell scorchification and reducing cerebral ischemia injury.

[Anti-pyroptosis effect of Albiziae Cortex-Tribuli Fructus combination on hepatic stellate cell line LX2: based on network pharmacology].

Based on network pharmacology, molecular docking, and in vitro experimental verification, this study aims to explore the effect of Albiziae Cortex-Tribuli Fructus combination on HSC-LX2 pyroptosis. Specifically, the targets of Albiziae Cortex, Tribuli Fructus, and hepatic fibrosis were retrieved from an online database and CNKI, and "drug-component-target" network and "drug-component-target-disease" network were constructed. Protein-protein interaction(PPI) network was established based on STRING. Metascape was employed for Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment, and the mechanism of Albiziae Cortex-Tribuli Fructus combination against liver fibrosis was predicted. Molecular docking was used to verify some of the results of network pharmacology, and in vitro experiment was carried out to further verify the above conclusions. According to the results of network pharmacological analysis, 25 active components and 439 targets of Albiziae Cortex-Tribuli Fructus combination and 152 anti-liver fibrosis targets were screened out, including nucleotide-binding oligomerization domain and leucine-rich-repeat-and pyrin-domain-containing 3(NLRP3) and caspase-1. The key targets were involved in 194 KEGG pathways in which the NOD-like receptor signaling pathway topped. The binding common targets were related to pyroptosis. The results of in vitro experiment showed that the pair-containing serum reduced the proliferation rate of HSC-LX2 and the content of reactive oxygen species(ROS), interleukin-18(IL-18), and interleukin-1ß(IL-1ß)(P<0.05). Western blot and qRT-PCR suggested that the protein and gene expression of NLRP3, caspase-1, α-smooth muscle actin(α-SMA), and gasdermin D(GSDMD) in HSC-LX2 increased after AngⅡ stimulation, and the expression decreased after the intervention of pair-containing serum(P<0.05). In summary, the pair-containing serum can inhibit the classic pathway of pyroptosis, which may be the anti-liver fibrosis mechanism. This is consistent with the predicted results of network pharmacology.

[Effects of Huangqin Tang on NLRP3/Caspase-1 pathway in mice model of ulcerative colitis].

The aim of this study was to explore the effects of Huangqin Tang(HQT) on the NLRP3/Caspase-1 signaling pathway in mice with DSS-induced ulcerative colitis(UC). C57BL/6J mice were randomly divided into a blank group, a model group(DSS group), and low-, medium-and high-dose HQT groups(HQT-L, HQT-M, and HQT-H), and western medicine mesalazine group(western medicine group). The UC model was induced in mice. Subsequently, the mice in the HQT-L, HQT-M, HQT-H groups, and the western medicine group were given low-, medium-, high-dose HQT, and mesalazine suspension by gavage, respectively, while those in the blank and DSS groups were given an equal volume of distilled water by gavage. After 10 days of administration, the body weight, DAI scores, and colonic histopathological score of mice in each group were determined. The levels of IL-6, IL-10, IL-1ß, and TNF-α in serum were determined by ELISA. The mRNA expression of NLRP3 and Caspase-1 in colon tissues was determined by RT-qPCR. The protein expression of NLRP3 and Caspase-1 in colon tissues was detected by immunohistochemistry. The results showed that compared with the blank group, the DSS group showed decreased body weight of mice and increased DAI scores and intestinal histopathological score. Compared with the DSS group, the HQT groups and the western medicine group showed improved DAI scores, especially in the HQT-M, HQT-H, and the western medicine groups(P<0.05). The intestinal histopathological scores of the HQT groups and the western medicine group significantly decreased, especially in the HQT-M, HQT-H, and the western medicine groups(P<0.05). In addition, compared with the blank group, the DSS group showed elevated expression of NLRP3 and Caspase-1 in colon tissues, increased serum levels of IL-6, IL-1ß, and TNF-α, and decreased IL-10 level. Compared with the DSS group, the HQT groups and the western medicine group displayed decreased expression of NLRP3 and Caspase-1 in colon tissues, reduced serum levels of IL-6, IL-1ß, and TNF-α, and increased IL-10 level. The improvement was the most significant in the HQT-H group and the western medicine group(P<0.01). In conclusion, HQT may reduce the expression of NLRP3 and Caspase-1 in colon tissues, reduce the se-rum levels of IL-6, IL-1ß, and TNF-α, and increase the expression of IL-10 by regulating the classic pyroptosis pathway of NLRP3/Caspase-1, thereby improving the symptoms of intestinal injury and inflammatory infiltration of intestinal mucosa in DSS mice to achieve its therapeutic effect.

Selenium Deficiency Promotes the Expression of LncRNA-MORC3, Activating NLRP3-Caspase-1/IL-1ß Signaling to Induce Inflammatory Damage and Disrupt Tight Junctions in Piglets.

Selenium (Se), as a trace element, is widely found in animals in the form of selenomethionine, which can provide nutrition to the body and has anti-inflammatory effects to prevent inflammatory damage in animals. In the past decade, there have been many studies on piglet diseases caused by selenium deficiency; however, under Se deficiency, the relationship between LncRNA-MORC3, inflammatory injury, and tight junctions in piglets has not yet been studied. We established piglet selenium deficiency models divided into three groups and obtained small intestinal tissues after 35 days of feeding. Small intestinal epithelial IPEC-J2 cells were divided into three groups, and samples were collected after 24 h of culture for qPCR and Western blot experiments. First, we found that Se deficiency led to an increase in LncRNA-MORC3 expression in piglets in vivo and in vitro. We found that the binding site of NLRP3 on LncRNA-MORC3 and the expression trends of both were the same: Se deficiency increased the secretion of NLRP3 and the expression levels of the inflammatory factors Caspase-1, ASC, IL-1ß, IL-17, IL-6, IL-10, and TNF-α, which are related to the NLRP3-Caspase-1/IL-1ß signaling pathway. At the same time, Se deficiency decreased the expression levels of the tight junction factors ZO-1, Z0-2, Occludin, E-cadherin, and ZEB-1. This result showed that the tight junctions were disrupted. Herein, we demonstrated that Se deficiency promotes the expression of both LncRNA-MORC3 and inflammatory factors in piglets to activate the NLRP3-Caspase-1/IL-1ß signaling pathway and disrupt tight junctions. Ultimately, these factors lead to inflammatory damage in piglet small intestinal tissues.

Effects of electroacupuncture on NLRP3/Caspase-1/GSDMD axis and neurological function in rats with cerebral ischemic reperfusion / 中国针灸

OBJECTIVE@#To investigate the neuroprotective effect of electroacupuncture (EA) at "Quchi" (LI 11) and "Zusanli" (ST 36) in the rats with cerebral ischemic reperfusion and the potential mechanism of microglia pyroptosis.@*METHODS@#Sixty SD rats were randomly divided into a sham-operation group, a model group and an EA group, with 20 rats in each group. The Zea Longa method was employed to establish the rat model of the middle cerebral artery occlusion and reperfusion (MACO/R) in the left brain. In the EA group, since the 2nd day of modeling, EA was given at "Quchi" (LI 11) and "Zusanli" (ST 36) of right side with disperse-dense wave, 4 Hz/20 Hz in frequency and 0.2 mA in current intensity, 30 min each time, once a day for lasting 7 consecutive days. The reduction rate of cerebral blood flow was measured with laser Doppler flowmetry during operation. The neurological function of rats was observed using Zea Longa neurobehavioral score. The cerebral infarction volume was detected by TTC staining method. The microglia positive expression in the ischemic side of the cortex was detected with the immunofluorescence method. Under transmission electron microscope, the ultrastructure of cell in the ischemic cortex was observed. The mRNA expression levels of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), cysteinyl aspartate specific proteinase-1 (Caspase-1) and gasdermin D (GSDMD) in the ischemic cortex were detected using real-time PCR.@*RESULTS@#Compared with the sham-operation group, in the model group, the reduction rate of cerebral blood flow was increased during operation (P<0.001); Zea Longa neurobehavional score and the percentage of cerebral infarction volume were increased (P<0.001), the numbers of M1-type microglia marked by CD68+ and M2-type microglia marked by TMEM119+ were elevated in the ischemic cortex (P<0.001), the mRNA expression of NLRP3, ASC, Caspase-1 and GSDMD was increased (P<0.001, P<0.01); the cytomembrane structure was destroyed, with more cell membrane pores formed in the ischemic cortex. Compared with the model group, after intervention, Zea Longa neurobehavioral score and the percentage of cerebral infarction volume were reduced (P<0.05), the number of M1-type microglia marked by CD68+ was reduced (P<0.05) and the number of M2-type microglia marked by TMEM119+ was increased (P<0.05); and the mRNA expression of NLRP3, ASC, Caspase-1 and GSDMD was decreased (P<0.01, P<0.05) in the EA group. Even though the cytomembrane structure was incomplete, there were less membrane pores presented in the ischemic cortex in the EA group after intervention.@*CONCLUSION@#The intervention with EA attenuates the neurological dysfunction and reduces the volume of cerebral infarction in the rats with cerebral ischemic reperfusion. The underlying mechanism is related to the inhibition of microglia pyroptosis through modulating NLRP3/Caspase-1/GSDMD axis.

Effects of Huangqin Tang on NLRP3/Caspase-1 pathway in mice model of ulcerative colitis / 中国中药杂志

The aim of this study was to explore the effects of Huangqin Tang(HQT) on the NLRP3/Caspase-1 signaling pathway in mice with DSS-induced ulcerative colitis(UC). C57BL/6J mice were randomly divided into a blank group, a model group(DSS group), and low-, medium-and high-dose HQT groups(HQT-L, HQT-M, and HQT-H), and western medicine mesalazine group(western medicine group). The UC model was induced in mice. Subsequently, the mice in the HQT-L, HQT-M, HQT-H groups, and the western medicine group were given low-, medium-, high-dose HQT, and mesalazine suspension by gavage, respectively, while those in the blank and DSS groups were given an equal volume of distilled water by gavage. After 10 days of administration, the body weight, DAI scores, and colonic histopathological score of mice in each group were determined. The levels of IL-6, IL-10, IL-1β, and TNF-α in serum were determined by ELISA. The mRNA expression of NLRP3 and Caspase-1 in colon tissues was determined by RT-qPCR. The protein expression of NLRP3 and Caspase-1 in colon tissues was detected by immunohistochemistry. The results showed that compared with the blank group, the DSS group showed decreased body weight of mice and increased DAI scores and intestinal histopathological score. Compared with the DSS group, the HQT groups and the western medicine group showed improved DAI scores, especially in the HQT-M, HQT-H, and the western medicine groups(P<0.05). The intestinal histopathological scores of the HQT groups and the western medicine group significantly decreased, especially in the HQT-M, HQT-H, and the western medicine groups(P<0.05). In addition, compared with the blank group, the DSS group showed elevated expression of NLRP3 and Caspase-1 in colon tissues, increased serum levels of IL-6, IL-1β, and TNF-α, and decreased IL-10 level. Compared with the DSS group, the HQT groups and the western medicine group displayed decreased expression of NLRP3 and Caspase-1 in colon tissues, reduced serum levels of IL-6, IL-1β, and TNF-α, and increased IL-10 level. The improvement was the most significant in the HQT-H group and the western medicine group(P<0.01). In conclusion, HQT may reduce the expression of NLRP3 and Caspase-1 in colon tissues, reduce the se-rum levels of IL-6, IL-1β, and TNF-α, and increase the expression of IL-10 by regulating the classic pyroptosis pathway of NLRP3/Caspase-1, thereby improving the symptoms of intestinal injury and inflammatory infiltration of intestinal mucosa in DSS mice to achieve its therapeutic effect.

Anti-pyroptosis effect of Albiziae Cortex-Tribuli Fructus combination on hepatic stellate cell line LX2: based on network pharmacology / 中国中药杂志

Based on network pharmacology, molecular docking, and in vitro experimental verification, this study aims to explore the effect of Albiziae Cortex-Tribuli Fructus combination on HSC-LX2 pyroptosis. Specifically, the targets of Albiziae Cortex, Tribuli Fructus, and hepatic fibrosis were retrieved from an online database and CNKI, and "drug-component-target" network and "drug-component-target-disease" network were constructed. Protein-protein interaction(PPI) network was established based on STRING. Metascape was employed for Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment, and the mechanism of Albiziae Cortex-Tribuli Fructus combination against liver fibrosis was predicted. Molecular docking was used to verify some of the results of network pharmacology, and in vitro experiment was carried out to further verify the above conclusions. According to the results of network pharmacological analysis, 25 active components and 439 targets of Albiziae Cortex-Tribuli Fructus combination and 152 anti-liver fibrosis targets were screened out, including nucleotide-binding oligomerization domain and leucine-rich-repeat-and pyrin-domain-containing 3(NLRP3) and caspase-1. The key targets were involved in 194 KEGG pathways in which the NOD-like receptor signaling pathway topped. The binding common targets were related to pyroptosis. The results of in vitro experiment showed that the pair-containing serum reduced the proliferation rate of HSC-LX2 and the content of reactive oxygen species(ROS), interleukin-18(IL-18), and interleukin-1β(IL-1β)(P<0.05). Western blot and qRT-PCR suggested that the protein and gene expression of NLRP3, caspase-1, α-smooth muscle actin(α-SMA), and gasdermin D(GSDMD) in HSC-LX2 increased after AngⅡ stimulation, and the expression decreased after the intervention of pair-containing serum(P<0.05). In summary, the pair-containing serum can inhibit the classic pathway of pyroptosis, which may be the anti-liver fibrosis mechanism. This is consistent with the predicted results of network pharmacology.

[Effect of Polygonati Rhizoma in improving pyroptosis injury of diabetic macroangiopathy via NLRP3/caspase-1/GSDMD pathway].

This study aims to explore the influence of Polygonati Rhizoma on the pyroptosis in the rat model of diabetic macroangiopathy via the NOD-like receptor thermal protein domain associated protein 3(NLRP3)/cysteinyl aspartate specific proteinase-1(caspase-1)/gasdermin D(GSDMD) pathway. The rat model of diabetes was established by intraperitoneal injection of streptozotocin(STZ) combined with a high-fat, high-sugar diet. The blood glucose meter, fully automated biochemical analyzer, hematoxylin-eosin(HE) staining, enzyme-linked immunosorbent assay, immunofluorescence, immunohistochemistry, and Western blot were employed to measure blood glucose levels, lipid levels, vascular thickness, inflammatory cytokine levels, and expression levels of pyroptosis-related proteins. The mechanism of pharmacological interventions against the injury in the context of diabetes was thus explored. The results demonstrated the successful establishment of the model of diabetes. Compared with the control group, the model group showed elevated levels of fasting blood glucose, total cholesterol(TC), triglycerides(TG) and low-density lipoprotein cholesterol(LDL-c), lowered level of high-density lipoprotein cholesterol(HDL-c), thickened vascular intima, and elevated serum and aorta levels of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß) and interleukin-18(IL-18). Moreover, the model group showed increased NLRP3 inflammasomes and up-regulated levels of caspase-1 and GSDMD in aortic vascular cells. Polygonati Rhizoma intervention reduced blood glucose and lipid levels, inhibited vascular thickening, lowered the levels of TNF-α, IL-1ß, IL-18 in the serum and aorta, attenuated NLRP3 inflammasome expression, and down-regulated the expression levels of caspase-1 and GSDMD, compared with the model group. In summary, Polygonati Rhizoma can slow down the progression of diabetic macroangiopathy by inhibiting pyroptosis and alleviating local vascular inflammation.

[Intervention effect of Jingfang Mixture on urticaria mice based on NF-κB/NLRP3/IL-1ß signaling pathway].

This study explored the curative effect of Jingfang Mixture on urticaria mice induced by aluminum hydroxide/ovalbumin, and discussed its mechanism. Sixty male Kunming mice were randomly divided into a normal group, a model group, three Jingfang Mixture(low-dose, medium-dose, and high-dose) groups, and a positive drug(cetirizine hydrochloride) group. The urticarial model in mice was induced by the intraperitoneal injection of the mixed solution of ovalbumin and aluminum hydroxide. The degrees of pruritus were observed after the second immunization. Pathological changes were detected by hematoxylin and eosin(HE) staining. Levels of interleukin 1ß(IL-1ß) and tumor necrosis factor α(TNF-α) in the serum were detected by enzyme linked immunosorbent assay(ELISA). Expressions of NOD-like receptor protein 3(NLRP3) and IL-1ß were detected by immunohistochemistry(IHC). Expressions of nuclear factor kappa-B(NF-κB p65), NLRP3, apoptosis-associated speck-like protein containing a CARD(ASC), cysteinyl aspartate-specific proteases 1(caspase-1), and IL-1ß proteins were detected by Western blot. The results showed that, except for the normal group, the mice in all groups had different degrees of pruritus. Compared with the model group, the Jingfang Mixture groups and the positive drug group prolonged the scratching latency of mice(P<0.05), and significantly reduced the number of scratching(P<0.05). In addition, the Jingfang Mixture groups and the positive drug group improved the pathological morphology of skin tissue. The expression levels of IL-1ß and TNF-α in serum were significantly reduced(P<0.05), and the number of NLRP3 and IL-1ß positive cells was decreased(P<0.01). The expressions of p-NF-κB p65, NLRP3, ASC, cleaved caspase-1, and IL-1ß protein were significantly down-regulated(P<0.05). The results of the above study indicate that Jingfang Mixture inhibit the inflammatory response in urticaria mice, and the mechanism may be related to the inhibition of activating NF-κB/NLRP3/IL-1ß signaling pathway.

[Effect of electroacupuncture regulating NLRP3/Caspase-1 pathway on pyroptosis of dopaminergic neurons in rats with Parkinson's disease].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the pyrolysis of dopaminergic neurons in rats with Parkinson's disease (PD), so as to explore its underlying molecular mechanism. METHODS: Male SD rats were randomly divided into the sham operation, model, EA, MCC950 and EA+MCC950 groups, with 12 rats in each group. The PD rat model was established by two-point injection of 6-OHDA. Rats in the MCC950 group were injected with MCC950 at the dose of 10 mg/kg, once a day; for rats of EA group, EA was applied to "Taichong" (LR3) and "Fengfu"(GV16) for 30 min, once a day; rats in the EA+ MCC950 group were given MCC950 injection and EA once a day. All above interventions were performed for 2 weeks. After the intervention, the behavioral changes of rats were observed using rotating induction experiment, rotating rod experiment and open field experiment; the positive expressions of dopaminergic neuronal markers tyrosine hydroxylase (TH) and α-Synuclein (α-Syn) in substantia nigra striatum were detected by immunohistochemistry; the damage of dopaminergic neurons in substantia nigra striatum was observed after HE staining; immunopositive coexpression of brain nucleotide-binding oligomerization domain like receptor protein 3 (NLRP3), Caspase-1 and ionized calcium binding adapter1 (Iba-1) were detected by immunofluorescence double staining; the levels of interleukin (IL)-1ß and IL-18 in brain tissues were detected by ELISA; the protein expression levels of NLRP3, Cleaved Caspase-1 and apoptosis-associated speck-like protein containing a CARD (ASC) in the substantia nigra striatum were detected by Western blot. RESULTS: Compared with the sham operation group, the number of rotations of rotating induction experiment, the residence time in the central area of open field experiment, the positive expression of α-Syn, the positive co-expressions of NLRP3/Iba-1 and Caspase-1/Iba-1, the contents of IL-1ß and IL-18 in brain tissues, and the protein expression levels of NLRP3, ASC and Cleaved Caspase-1 in substantia nigra striatum were significantly increased (P<0.05), while the drop latency of rotating rod experiment, the rearing times and the total distance of open field experiment, and the positive expression of TH in substantia nigra striatum were significantly decreased (P<0.05) in the model group. Compared with the model group, the above mentioned markers were reversed in EA, MCC950 and EA+MCC950 groups (P<0.05), and the improvement of the EA+MCC950 group was more obvious than those of the MCC950 and EA groups. In the model group, the neurons were disorderly arranged, the number of neurons was reduced, the cytoplasm was swollen, and some of them were vacuolar degeneration; while the degree of neuronal arrangement disorder, cytoplasmic swelling and the vacuolar degeneration were reduced in varying degrees in the MCC950, EA and EA+MCC950 groups. CONCLUSION: The ameliorative effect of EA on dopaminergic neuron damage in PD rats may be related to its effects in inhibiting NLRP3/Caspase-1 mediated neuronal pyrosis.

[Effect of heat-reinforcing needling on expression of P2X7R, NLRP3 and Caspase-1 in synovial tissues of knee joint in rabbits with cold syndrome rheumatoid arthritis].

OBJECTIVE: To observe the effects of heat-reinforcing needling on the expression of purinergic ligand-gated ion channel 7 receptor(P2X7R)，Nodlike receptor protein 3(NLRP3) and Caspase-1 in synovium tissues of knee joint of rabbits with cold syndrome rheumatoid arthritis(RA)，so as to explore the anti-inflammatory mechanism of heat reinforcing needling in the treatment of RA. METHODS: Thirty male New Zealand white rabbits were randomly divided into normal group, model group, reinforcing-reducing needling group(RRG), heat-reinforcing needling group(HRG), and antagonist group(AG), with 6 rabbits in each group.The model of cold syndrome RA was established by ovalbumin combined with Freund's adjuvant and cryogenic freezing. Rabbits of RRG and HRG were treated with corresponding acupuncture techniques on both sides of "Zusanli"(ST36) for 30 min, once a day for 7 days; Rabbits of the AG was intraperitoneally injected with A438079(2.5 mg/kg), once a day for 7 days. After intervention, color Doppler ultrasound was used to observe the joint cavity effusion, synovial thickness and internal blood flow signal.The histomorphological changes of synovial tissues were observed by HE staining. Quantitative real-time PCR method was used to detect the mRNA expression levels of P2X7R, NLRP3, and Caspase-1 in synovial tissues. Western blot was used to detect the protein expression of interleukin(IL)-1ß, IL-6 and tumor necrosis factor(TNF)-α in synovial tissues. RESULTS: Compared with the normal group, the synovial tissues in the model group was thickened, linear and punctate blood flow signals were increased, joint effusion was obvious, synovial coating cells were enlarged, the synovial matrix was severely hyperplasia, inflammatory cells infiltration was obvious.The mRNAs expression levels of P2X7R, NLRP3, Caspase-1 and IL-1ß, IL-6, TNF-α proteins in synovial tissues were significantly increased(P<0.01). Compared with model group, abnormal blood flow signals, synovial thickness, joint effusion, proliferation of synovial matrix, inflammatory cell infiltration and synovial coating cells in the RRG, HRG and AG were improved. The mRNAs expression levels of P2X7R, NLRP3, Caspase-1 and IL-1ß, IL-6, TNF-α proteins in synovial tissues were decreased in the RRG, HRG and AG (P<0.05, P<0.01). Compared with the RRG, the above indexes were lower in the HRG and AG (P<0.05, P<0.01).There was no significant difference in all indexes above between the HRG and AG (P<0.01, P<0.05). CONCLUSION: Heat reinforcing needling can improve synovial inflammation of RA, which may be related to regulating the expressions of P2X7R/NLRP3/Caspase-1 signaling pathway.

Sennoside A is a novel inhibitor targeting caspase-1.

The assembly of inflammasomes drives caspase-1 activation, which further promotes proinflammatory cytokine secretion and downstream pyroptosis. The discovery of novel caspase-1 inhibitors is pivotal to developing new therapeutic means for inflammasome-involved diseases. In our present study, sennoside A (Sen A), a popular ingredient in multiple weight-loss medicines and dietary supplements, is found to potently inhibit the enzymatic activity of caspase-1 in vitro. Sen A considerably decreased IL-1ß production in macrophages stimulated by LPS plus ATP, nigericin or MSU as well as poly(dA:dT) transfection, and remedied ROS-involved pyroptosis via caspase-1 inhibition. Mechanistically, Sen A not only suppressed the assembly of both NLRP3 and AIM2 inflammasome but also affected the priming process of NLRP3 inflammasome by blocking NF-κB signaling. Sen A significantly ameliorated the pathophysiological effect in LPS-, MSU- and carrageenan-challenged rodent models by suppressing inflammasome activation. Furthermore, P2X7 was indispensable for Sen A inhibiting NLRP3 inflammasome since it failed to further decrease IL-1ß and IL-18 production in LPS plus ATP-stimulated BMDMs that were transfected with P2X7 siRNA. Sen A also restrained the large pore-forming functionalities of the P2X7R as verified by the YO-PRO-1 uptake assay. Taken together, Sen A inactivates caspase-1 to inhibit NLRP3 and AIM2 inflammasome-involved inflammation in a P2X7-dependent manner, making it an attractive candidate as a caspase-1 small-molecular inhibitor.

Kaempferol-3-O-rutinoside exerts cardioprotective effects through NF-κB/NLRP3/Caspase-1 pathway in ventricular remodeling after acute myocardial infarction.

Ventricular remodeling (VR) after acute myocardial infarction (AMI) is the main pathogenesis of chronic heart failure (CHF). Kaempferol-3-O-rutinoside (KR) is the flavonoid glycoside with the highest content in Lu'an GuaPian tea, which has good pharmacological activities. However, the mechanism of KR against VR after AMI remains unclear. Molecular docking was used to predict the targets of KR on the NLRP3/Caspase-1 signaling pathway. Histological changes in the myocardium were visualized using HE staining, Masson staining. Cardiomyocyte apoptosis was detected using TUNEL. Immunohistochemistry was used to examine NLRP3, Caspase-1 p20, and GSDMD. IL-1ß level in serum was detected using ELISA. Finally, the expressions of NF-κB p65, NLRP3, ASC, Caspase-1 p20, GSDMD, and IL-1ß were measured using RT-PCR and Western blotting. Our results showed that KR had a good binding activity with NLRP3, Caspase-1, and GSDMD, significantly improved cardiac function, alleviated cardiac pathological changes, reduced the excessive deposition of myocardial interstitial collagen, and inhibited cardiomyocyte apoptosis in AMI rats. Furthermore, KR could decrease the IL-1ß level and inhibit the expressions of NF-κB p65, NLRP3, ASC, Caspase-1 p20, GSDMD, and IL-1ß. Our study suggests that KR can prevent and treat VR after AMI, and the protective effect is related to its regulatory NF-κB/NLRP3/Caspase-1 signaling pathway. PRACTICAL APPLICATIONS: Kaempferol-3-O-rutinoside is present in Carthamus tinctorius L., Nymphaea candida, Afgekia mahidoliae and green tea, which has good pharmacological activities against liver injury, cerebral ischemia/reperfusion injury, dementia, hyperglycemia, and myocardial infarction. Our previous study found that kaempferol-3-O-rutinoside had an obvious anti-inflammatory effect, and could significantly improve the cell survival rate of H9c2 myocardium inflammatory injury induced by LPS. In this study, kaempferol-3-O-rutinoside significantly improved cardiac function, alleviated cardiac pathological changes, reduced the excessive deposition of myocardial interstitial collagen, and inhibited cardiomyocyte apoptosis in AMI rats. Furthermore, kaempferol-3-O-rutinoside could decrease the IL-1ß level and inhibit the expressions of NF-κB p65, NLRP3, ASC, Caspase-1, GSDMD and IL-1ß, suggesting that kaempferol-3-O-rutinoside could regulate NF-κB/NLRP3/Caspase-1 signaling pathway.

[Effect of electroacupuncture preconditioning on expression of Gasdermin D, Caspase-1 and IL-1ß in rats with myocardial ischemia reperfusion injury].

OBJECTIVE: To observe the effect of electroacupuncture(EA) preconditioning on expression of Caspase-1, Gasdermin D(GSDMD) and interleukin-1ß(IL-1ß) in myocardial tissue of myocardial ischemia reperfusion injury (MIRI) rats in order to explore its underlying mechanisms in resisting MIRI. METHODS: Forty male rats were randomly divided into 4 groups: normal control (normal), sham operation (sham), MIRI model and EA groups. The MIRI model was established by ligation of the left anterior descending branch of the left coronary artery for 30 min and perfusion. EA (2 Hz/100 Hz, 1 mA) was applied to bilateral "Neiguan" (PC6) for 20 min, once a day for 3 consecutive days. The echocardiography was used to analyze the left ventricular end-diastolic dimension (LVEDD), left ventricular end-systolic dimension (LVESD) and left ventricular ejection fraction (LVEF, by using Teichholz formula) 4 h after modeling. The myocardial TTC staining was used to observe the proportion of the infarct area, and Western blot was used to detect the expression levels of GSDMD, Caspase-1, IL-1ß proteins in the myocardium. RESULTS: Compared with the normal group, the immunoactivity of GSDMD was increased in the sham group (P<0.05). Compared with the sham group, the LVEF was significantly decreased (P<0.000 1), while the myocardial infarction area, immunoactivity of GSDMD, and the expression levels of Caspase-1, GSDMD and IL-1ß proteins were considerably increased in the model group (P<0.000 1, P<0.001). In comparison with the model group, the decreased ejection fraction and the increased myocardial infarction area, and Caspase-1, GSDMD and IL-1ß expression were reversed in the EA group (P<0.001, P<0.000 1, P<0.01). CONCLUSION: EA preconditioning may ameliorate myocardial injury in MIRI rats which may be associated with its function in down-regulating the expression of myocardial Caspase-1 protein to reduce cardiomyocyte pyroptosis.

Uranium induces kidney cells pyroptosis in culture involved in ROS/NLRP3/caspase-1 signaling.

Pyroptosis is an exceptional mode of inflammation and programmed cell death involved in inflammasomes and Caspase-1 activation and inflammatory cytokines releasing. Our goal is to explore whether uranium (U)-intoxication could induce NRK-52E cells pyroptosis in vitro and its underlying molecular mechanism. Rat NRK-52E cells were intoxicated with U concentrations (400-500 µM) for 24 h. The results indicate that the cells showed characteristic features of pyroptosis, which were identified through augmented NLRP3 and cleaved Caspase-1 proteins expression, GSDMD mRNA level, mature interleukin IL-18 and IL-1ß contents, LDH leakage, and the number of double-positive cells. But, administration of glycine (an inhibitor of pyroptosis) effectively attenuated U-induced pyroptosis, LDH releasing and cytotoxicity. Pretreatment of CRID3 (an inhibitor of NLRP3 inflammasome) evidently abrogated NLRP3 and cleaved Caspase-1 proteins and GSDMD mRNA expression which all were up-regulated by U exposure. Simultaneously, CRID3 significantly reversed U-increased pyroptosis rate and active interleukin IL-18 and IL-1ß contents. NAC application (an ROS scavenger) effectively decreased U-increased ROS content and NLRP3 expression and restored U-induced pyroptosis. Taken together, our results suggest that U-treatment can trigger NRK-52E cells pyroptosis which is involvement of ROS/NLRP3/Caspase-1 pathway. Targeting ROS/NLRP3/Caspase-1-mediated pyroptosis may be a novel approach for attenuating U nephrotoxicity.