Frontiers in Cellular and Infection Microbiology
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2021
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IF 5.293
Zhang Wei,Li Zhixing,Yang Haitao,Wang Guanglu,Liu Gang,Wang Yu,Bello Babatunde Kazeem,Zhao Panpan,Liang Wei,Dong Jingquan
Aeromonas sobria, a common conditional pathogenic bacteria, is widely distributed in the environment and causes gastroenteritis in humans or septicemia in fish. Of all Aeromonas species, A. sobria is the most frequently isolated from human infections especially in immunocompromised subjects. Innate immunity is the first protection system of organism to resist non-specific pathogens invasion; however, the immune response process of hosts against A. sobria infection re\mains unexplored. The present study established an A. sobria infection model using primary mouse peritoneal macrophages (PMφs). The adherence and cytotoxicity of A. sobria on PMφs were determined by May-Grünwald Giemsa staining and LDH release measurement. Pro-inflammatory cytokine expression levels were measured using qPCR, western blotting, and ELISA methods. We also investigated the levels of ASC oligomerization and determined the roles of active caspase-1 in IL-1β secretion through inhibition assays and explored the activated pattern recognition receptors through immunofluorescence. We further elucidated the roles of activated inflammasome in regulating the host’s inflammatory response through inhibition combined with ELISA assays. Our results showed that A. sobria induced lytic cell death and LDH release, whereas it had no adhesive properties on PMφs. A. sobria triggered various proinflammatory cytokine transcription level upregulation, and IL-1β occupied the highest levels. The pro-IL-1β protein expression levels increased in a dose-dependent manner with MOI ranging from 1 to 100. This process was regulated by ASC-dependent inflammasome, which cleavage pro-IL-1β into active IL-1β p17 with activated caspase-1 p20. Meanwhile, the expression levels of NLRP3 receptor significantly increased, location analysis revealed puncta-like surrounding nuclear, and inhibition of NLRP3 inflammasome downregulated caspase-1 activation and IL-1β secretion. Blocking of NLRP3 inflammasome activation through K+ efflux and cathepsin B or caspase approaches downregulated A. sobria–induced proinflammatory cytokine production. Overall, these data indicated that A. sobria induced proinflammatory cytokine production in PMφs through activating NLRP3 inflammasome signaling pathways.
研究领域:
免疫学
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微生物学
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细胞生物学
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传染病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2023
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IF 11.2
E Zhang,Chuangeng Shang,Mingtao Ma,Xuanfeng Zhang,Yu Liu,Shuliang Song,Xia Li
Polyguluronic acid (PG), a polysaccharide from alginate , possesses excellent bioactivities. We prepared high-purity PG with 10.41 kDa molecular weight (Mw) and a 59 average degree of polymerization (DP) by acid hydrolysis , three pH grades, Q-Sepharose column elution, and Sephadex G-25 column desalination . Then, we evaluated the PG protective effects on doxorubicin-induced cardiotoxicity (DIC) in vitro and in vivo. The nontoxic PG enhanced cellular viability , reduced cell pyroptosis morphology, diminished the LDH and IL-1β release, and downregulated expressions of ASC oligomerization , NLRP3 , cl-CASP1, and GSDMD, by which PG protected the cardiomyocytes from NLRP3 inflammasome-mediated pyroptosis in doxorubicin-stimulated HL-1 cells and C57BL/6J mice. The probable underlying mechanism may be that PG downregulated doxorubicin -induced Peli1, the deficiency of which could inhibit doxorubicin-induced NLRP3 inflammasome-mediated pyroptosis. These results suggested that polysaccharide PG from alginate could prevent DIC and may be a potential therapeutic agent or bioactive material for preventing DIC.
研究领域:
药理学
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心脏病学
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免疫学
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生物化学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
METABOLISM-CLINICAL AND EXPERIMENTAL
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2021
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IF 8.697
Suling Huang,Yanwei Wu,Zhuohui Zhao,Bing Wu,Kai Sun,Haoyu Wang,Li Qin,Fang Bai,Ying Leng,Wei Tang
Objective Obeticholic acid (OCA) has been proved to play potential therapeutic effect on nonalcoholic steatohepatitis (NASH). Up to now, the study of OCA on NLRP3 inflammasome activation in macrophage is still blank and merits great attention. Here, we aimed to better characterize the role and mechanism of OCA on NASH treatment focusing on NLRP3 inflammasome activation in macrophages. Methods The effects of OCA on inflammasome activation were investigated in BMDM , Kupffer cell , BMDC and LX2 cell. Preconditioned media from BMDM culture was used to treat primary hepatocytes to explore the effects of macrophage NLRP3 inflammasome activation on the function of hepatocytes. In vivo, high fat diet plus CCl 4 (DIO + CCl 4 ) induced murine NASH model and choline-deficient and amino acid-defined (CDA) diet-induced NASH mice were used to verify the inhibitory effect of OCA on inflammasome activation in liver macrophages and recapitulate its protective role on NASH progressing. To clear up the effect of OCA on macrophage is FXR dependent or not, FXR siRNA was introduced into BMDMs. Results OCA blockaded NLRP3 inflammasome in BMDMs by impacting on the activation stage and disrupting ASC oligomerization . Preconditioned supernatant from LPS + ATP treated BMDMs increased mRNA expression of lipogenic enzymes and lipid content, whereas preconditioned supernatant from OCA treated BMDM blocked these effects in both normal and the FXR knockdown hepatocytes. In DIO + CCl 4 mice, the population of inflammatory myeloid lineage cells in livers was decreased upon OCA treatment. Accordingly, the level of IL-1β and IL-18 in liver, the hepatic expression of ASC, pro-caspase-1 and active caspase-1, the expression of caspase 1 p20 in liver macrophages were also reduced. Similar results were obtained in CDA diet-fed mice. Furthermore, OCA maintained the inhibition on NLRP3 inflammasome activation in FXR knockdown BMDMs, suggesting FXR could be dispensable in this effect. Conclusions This finding brings up a new mechanism of OCA on NASH treatment, suggested by direct inhibition on NLRP3 inflammasome activation in macrophage, further suppression on inflammasome activation-elicited hepatic lipid accumulation , and contributing to the amelioration of NASH.
研究领域:
药理学
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免疫学
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肝病学
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细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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