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.

Therapeutic mechanism of Psammosilene tunicoides extract on rheumatoid arthritis based on NLRP3 inflammasome / 中国中药杂志

In this study, we investigated the mechanism of crude extract of Psammosilene tunicoides(CEPT) in the treatment of rheumatoid arthritis(RA) based on the Nod-like receptor protein 3(NLRP3) inflammasome. The collagen-induced arthritis(CIA) mouse model was established. On day 32 after the primary immunization, according to the arthritis score, the mice were randomly divided into model group, positive control(methotrexate) group, low-and high-dose CEPT groups, and normal group, with 10 mice in each group. According to the administration dose of each group, the mice were continuously administered for 21 days. Every four days during the administration, the paw edema degree, arthritis score, and spleen index of the mice were measured; histopathological examination was performed for the ankles of the mice; the contents of IL-1β and IL-18 in the serum were determined; the protein expression levels of NLRP3, caspase-1, and apoptosis-associated speck-like protein containing a CARD(ASC), as well as the mRNA expression levels of NLRP3 and caspase-1 in the ankle joints of the mice were detected. The results showed that compared with those in the model group, the mice in the positive control group and CEPT groups had significantly decreased the contents of IL-1β and IL-18 in the serum and spleen index(P<0.01), significantly lowered arthritis score and degree of paw edema(P<0.01), alleviated arthritic infiltration of the knee, and down-regulated protein and mRNA levels of NLRP3, ASC, and caspase-1 in the ankle joint(P<0.01). These results suggest that P. tunicoides may reduce the paw edema and arthritis score and alleviate the inflammatory response in CIA mice by inhibiting the expression of NLRP3. This study provides a basis for the study of immune regulation of P. tunicoides in RA.

Mechanism of Huanglian Wendan Decoction in improving impaired glucose tolerance based on skeletal muscle NLRP3/caspase-1/IL-1β, IL-18 pathway / 中国中药杂志

This study investigated the mechanism of improving impaired glucose tolerance(IGT) of rats by Huanglian Wendan Decoction from the perspective of the skeletal muscle Nod-like receptor protein 3(NLRP3)/cysteinyl aspartate specific proteinase-1(caspase-1)/interleukin-1β(IL-1β), interleukin-18(IL-18) pathway. Healthy male SD rats were fed with the diet containing 45% fat for 20 weeks, accompanied by a high-temperature and high-humidity environment and an inactive lifestyle, for the establishment of the IGT rat model. The rats were divided into the blank control group, model control group, metformin hydrochloride group(positive drug group, 0.05 g·kg~(-1)·d~(-1)) and Huanglian Wendan Decoction group(7.8 g·kg~(-1)·d~(-1)). After continuous intragastric administration for 4 weeks, the obesity and glycemic indexes of all the rats were measured. The fasting serum insulin(FINS) level was determined by ELISA, with the insulin sensitivity index(ISI) and insulin resistance index(IRI) calculated. The mRNA and protein expression le-vels of nuclear factor kappaB(NF-κB), NLRP3, caspase-1, IL-1β and IL-18 in skeletal muscle tissue were detected by real-time polymerase chain reaction(PCR), Western blot and immunofluorescence. Compared with the blank control group, the model control group witnessed significantly increased mRNA and protein expression of NF-κB, NLRP3, caspase-1, IL-1β and IL-18. As revealed by the comparison with the model control group, Huanglian Wendan Decoction could effectively regulate the obesity status, reduce body weight, correct the abnormal levels of 2-hour plasma glucose(2 hPG), insulin resistance index(IRI), insulin sensitivity index(ISI), and lower the mRNA and protein expression of NF-κB, NLRP3, caspase-1, IL-1β and IL-18 in the skeletal muscle tissue of IGT rats. Combined with previous studies, the above results showed that the occurrence and development of IGT was closely related to inflammatory response and the classic pyroptosis pathway in skeletal muscle, such as NLRP3/caspase-1/IL-1β, IL-18. It is inferred that the mechanism of Huanglian Wendan Decoction was to alleviate insulin resistance(IR) and then reverse the course of IGT lies in the regulation of the abnormal insulin receptor signaling pathway based on the NLRP3 inflammasome pathway.

Effect of Huangqin Decoction on pyroptosis pathway of NLRP3/caspase-1 in mice with ulcerative colitis / 中国中药杂志

To explore the effect of Huangqin Decoction on ulcerative colitis(UC) pyroptosis, and to explain the mechanism of pyroptosis based on NOD-like receptor thermoprotein domain 3(NLRP3)/cysteine proteinase 1(caspase-1) pathway. The animal model of UC induced with 3% dextran sodium sulfate(DSS) was established. The experimental animals were divided into control group, model group, low-dose(4.55 g·kg~(-1)), medium-dose(9.1 g·kg~(-1)) and high-dose(18.2 g·kg~(-1)) Huangqin Decoction groups and salazosulfapyridine group(0.45 g·kg~(-1)). While modeling, intragastric administration was given for 7 consecutive days. On the 8 th day, the mice were euthanized, the colon length was collected, and the histopathological changes were observed by HE staining. The content of interleukin-18(IL-18) was observed by ELISA. The content of lactatedehydrogenase(LDH)was determined by microplate method. TUNEL assay kit was used to detect the cell death. The immunohistochemical staining was used to detect the expressions of NLRP3 and apoptosis-associated speck-like protein containing a CARD(ASC). Western blot was used to detect the expressions of interleukin-1β(IL-1β), caspase-1 and gasdermin D(GSDMD).The experimental study showed that compared with normal group, the LDH content, TUNEL positive staining, inflammatory factors(IL-18, IL-1β), and proteins associated with pyroptosis were significantly increased(P<0.05). Compared with model control group, the LDH content, TUNEL positive staining, inflammatory factors(IL-18, IL-1β), and proteins associated with pyroptosis were decreased, and these results were more significant in high-dose groups(P<0.05). The results of HE staining showed that Huangqin Decoction could improve the pathological changes of colon. Huangqin Decoction could inhibit UC cell pyroptosis, and the mechanism may be closely related to NLRP3/caspase-1 signaling pathway.

The role of atenolol in the modulation of the expression of genes encoding pro- (caspase-1) and anti- (Bcl2L1) apoptotic proteins in endothelial cells exposed to intestinal ischemia and reperfusion in rats

Abstract Purpose: To investigate the role of atenolol in the gene expression of caspase 1 (Casp1) and Bcl2L1 on vascular endothelium of rat intestine after ischemia and reperfusion (IR). Methods: Eighteen adult male Wistar rats were randomly divided into 3 groups (n=6): SG (Sham group): no clamping of the superior mesenteric artery; IRG: IR plus saline group: IRG+At: IR plus Atenolol group. Rats from IRG and IRG+At were subjected to 60 min of intestinal ischemia and 120 min of reperfusion. Atenolol (2mg/kg) or saline were injected in the femoral vein 5 min before ischemia, 5 min and 55 min after reperfusion. Thereafter, intestinal segments were appropriately removed and processed for Endothelial Cell Biology Rat RT2 Profiler PCR Array. Results: the anti-apoptotic Bcl2L1 gene expression was significantly down-regulated (-1.10) in the IRG and significantly up-regulated in the IRG+At (+14.15). Meanwhile, despite Casp1 gene expression was upregulated in both groups, it was significantly higher in the IRG (+35.06) than the IRG+At (+6.68). Conclusions: Atenolol presents antiapoptotic effects on rat intestine subjected to IR partly by the up-regulation of the anti-apoptotic Bcl2L1 gene expression. Moreover, atenolol can mitigate the pro-apoptotic and pro-inflammatory effects of Casp1 gene on rat intestine after IR.

Association of caspase-1 polymorphisms with Chagas cardiomyopathy among individuals in Santa Cruz, Bolivia

Abstract INTRODUCTION: Trypanosoma cruzi (Tc) infection is usually acquired in childhood in endemic areas, leading to Chagas disease, which progresses to Chagas cardiomyopathy in 20-30% of infected individuals over decades. The pathogenesis of Chagas cardiomyopathy involves the host inflammatory response to T. cruzi, in which upstream caspase-1 activation prompts the cascade of inflammatory chemokines/cytokines, cardiac remodeling, and myocardial dysfunction. The aim of the present study was to examine the association of two caspase-1 single nucleotide polymorphisms (SNPs) with cardiomyopathy. METHODS: We recruited infected (Tc+, n = 149) and uninfected (Tc−, n = 87) participants in a hospital in Santa Cruz, Bolivia. Cardiac status was classified (I, II, III, IV) based on Chagas cardiomyopathy-associated electrocardiogram findings and ejection fractions on echocardiogram. Genotypes were determined using Taqman probes via reverse transcription-polymerase chain reaction of peripheral blood DNA. Genotype frequencies were analyzed according to three inheritance patterns (dominant, recessive, additive) using logistic regression adjusted for age and sex. RESULTS: The AA allele for the caspase-1 SNP rs501192 was more frequent in Tc+ cardiomyopathy (classes II, III, IV) patients compared to those with a normal cardiac status (class I) [odds ratio (OR) = −2.18, p = 0.117]. This trend approached statistical significant considering only Tc+ patients in class I and II (OR = −2.64, p = 0.064). CONCLUSIONS: Caspase-1 polymorphisms may play a role in Chagas cardiomyopathy development and could serve as markers to identify individuals at higher risk for priority treatment.

Black rice anthocyanidins prevent retinal photochemical damage via involvement of the AP-1/NF-kappaB/Caspase-1 pathway in Sprague-Dawley Rats

The effects of black rice anthocyanidins (BRACs) on retinal damage induced by photochemical stress are not well known. In the present study, Sprague-Dawley rats were fed AIN-93M for 1 week, after which 80 rats were randomly divided into two groups and treated with (n = 40) or without BRACs (n = 40) for 15 days, respectively. After treatment, both groups were exposed to fluorescent light (3,000 +/- 200 lux; 25degrees C), and the protective effect of dietary BRACs were evaluated afterwards. Our results showed that dietary BRACs effectively prevented retinal photochemical damage and inhibited the retinal cells apoptosis induced by fluorescent light (p < 0.05). Moreover, dietary BRACs inhibited expression of AP-1 (c-fos/c-jun subunits), up-regulated NF-kappaB (p65) expression and phosphorylation of IkappaB-alpha, and decreased Caspase-1 expression (p < 0.05). These results suggest that BRACs improve retinal damage produced by photochemical stress in rats via AP-1/NF-kappaB/Caspase-1 apoptotic mechanisms.