scholarly journals Molecular mechanism of pyroptosis of mononuclear macrophages induced by pathogenic E. coli high pathogenicity island (HPI) in Yunnan Saba pigs

2020 ◽  
Author(s):  
Chunlan Shan ◽  
Shushu Miao ◽  
Chaoying Liu ◽  
Weiwei Zhao ◽  
Bo Zhang ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Molecular Mechanism ◽  
Pathogenicity Island ◽  
Control Group ◽  
Tunel Staining ◽  
Membrane Pore ◽  
Expression Levels ◽  
E Coli ◽  
Caspase 1 ◽  
High Pathogenicity

Abstract Background In this study we evaluated the molecular mechanism by which pyroptosis is induced in mononuclear macrophages isolated from Saba pigs following infection with pathogenic E. coli high pathogenicity island (HPI). Mononuclear macrophages were divided into four treatment groups: control, Lipopolysaccharide (LPS) + adenosine triphosphate (ATP), HPI positive (+) strain and HPI negative (-) strain. The mononuclear macrophages and their culture supernatants were collected at 0.5, 3, 6, 9, 12 and 24 h after infection. DNA changes were detected by TUNEL staining and the integrity of the cell membrane was evaluated by propidium iodide (PI) staining. Changes in mRNA expression levels of NLRP3, caspase-1, IL-1β, and IL-18 gene in mononuclear macrophages were analyzed by quantitative real-time polymerase chain reaction (RT-PCR) and caspase-1 protein expression was detected by indirect immunofluorescence. IL-1β and IL-18 concentration in the mononuclear macrophage culture supernatant were measured by ELISA. Results Compared with the control group, TUNEL and PI staining of mononuclear macrophages was significantly increased following infection with the HPI + /HPI - strains ( P < 0.01 or P < 0.05), with significantly higher levels detected in the HPI + group compared with those in the HPI - group ( P < 0.01 and P < 0.05). Compared with the control group, the expression levels of NLRP3, caspase-1, IL-1β, and IL-18 in the HPI groups were upregulated after pathogenic E. coli infection, with significantly higher levels detected in the HPI + group compared with those in the HPI - group ( P < 0.01 or P < 0.05). Conclusions These findings showed that pathogenic E. coli HPI infection of Saba pigs results induced pyroptosis of mononuclear macrophages characterized by increased expression of NLRP3, caspase-1, IL-1β and IL-18 mRNA in mononuclear macrophages, the induction of cell membrane pore formation, nuclear DNA damage, and the secretion of IL-1β and IL-18 to enhance the inflammatory response.

scholarly journals Induction of macrophage pyroptosis-related factors by pathogenic E. coli high pathogenicity island (HPI) in Yunnan Saba pigs

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Chunlan Shan ◽  
Shushu Miao ◽  
Chaoying Liu ◽  
Bo Zhang ◽  
Weiwei Zhao ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Inflammatory Diseases ◽  
Pathogenicity Island ◽  
Cell Membrane Permeability ◽  
Inflammatory Factor ◽  
Related Factors ◽  
Membrane Pore ◽  
E Coli ◽  
Caspase 1 ◽  
High Pathogenicity

Abstract Background Pyroptosis plays a pivotal role in the pathogenesis of many inflammatory diseases. The molecular mechanism by which pyroptosis is induced in macrophages following infection with pathogenic E. coli high pathogenicity island (HPI) will be evaluated in our study. Results After infection with the HPI+/HPI− strains and LPS, decreased macrophage cell membrane permeability and integrity were demonstrated with propidium iodide (PI) staining and the lactate dehydrogenase (LDH) assay. HPI+/HPI−-infection was accompanied by upregulated expression levels of NLRP3, ASC, caspase-1, IL-1β, IL-18 and GSDMD, with significantly higher levels detected in the HPI+ group compared to those in the HPI− group (P < 0.01 or P < 0.05). HPI+ strain is more pathogenic than HPI− strain. Conclusion Our findings indicate that pathogenic E. coli HPI infection of Saba pigs causes pyroptosis of macrophages characterized by upregulated expression of pyroptosis key factors in the NLRP3/ASC/caspase-1 signaling pathway, direct cell membrane pore formation, and secretion of the inflammatory factor IL-1β and IL-18 downstream of NLRP3 and caspase-1 activation to enhance the inflammatory response.

scholarly journals Expression of AIM2 in rheumatoid arthritis and its role on fibroblast-like synoviocyte

2020 ◽  
Author(s):  
fujuan qiu ◽  
Chen Yong ◽  
Qiu Fujuan ◽  
Zhao Xiaofeng ◽  
Xiao Changhong
Keyword(s):  
Rheumatoid Arthritis ◽  
Mtt Assay ◽  
Control Group ◽  
Expression Levels ◽  
Potential Target ◽  
Caspase 1 ◽  
Significant Difference ◽  
And Migration ◽  
Fibroblast Like Synoviocytes ◽  
Proliferation And Migration

Abstract Background To determine whether any differences of AIM2 inflammasome expression levels between rheumatoid arthritis (RA) and osteoarthritis (OA) and investigate the effects of AIM2 when transferred into RA fibroblast-like synoviocytes (RA-FLS).Methods Serum AIM2 levels between OA and RA patients were compared by ELISA. Different expression levels of AIM2, ASC, Caspase-1 and IL-1β between RA and OA synovium were semi-quantified by RT-qPCR and immunohistochemical (IHC) staining. IHC staining were recorded by H scores, and determine the correlation with ESR and CRP levels of RA patients. SiRNA AIM2 was transferred to RA-FLS and observe its effects on proliferation and migration by MTT assay and transwell test respectively.Results In RA sera, no significant difference was observed between OA and RA patients. However, in affected knee synovium, AIM2, ASC, Caspase-1 and IL-1β were expressed higher in RA than that of OA. Plus, H score of AIM2, ASC, and IL-1β were positively correlated to ESR and CRP levels in RA patients. After transferred AIM2 siRNA to FLS and incubation for 48 hours, the proliferation of FLS were significantly inhibited, and the apoptosis rate were significantly increased compared to FLS in control group. However, no effect on migration was detected.Conclusions AIM2 participated in the proliferation of FLS, and might be a potential target for therapy.

scholarly journals Prevalence of the “High-Pathogenicity Island” of Yersinia Species among Escherichia coliStrains That Are Pathogenic to Humans

1998 ◽  
Vol 66 (2) ◽  
pp. 480-485 ◽  
Author(s):  
S. Schubert ◽  
A. Rakin ◽  
H. Karch ◽  
E. Carniel ◽  
J. Heesemann
Keyword(s):  
Gene Cluster ◽  
Yersinia Pseudotuberculosis ◽  
Pathogenicity Island ◽  
Uptake System ◽  
Highly Pathogenic ◽  
E Coli ◽  
Yersinia Species ◽  
The Family ◽  
High Pathogenicity ◽  
Dna Sequence Comparison

ABSTRACT The fyuA-irp gene cluster contributes to the virulence of highly pathogenic Yersinia (Yersinia pestis,Yersinia pseudotuberculosis, and Yersinia enterocolitica 1B). The cluster encodes an iron uptake system mediated by the siderophore yersiniabactin and reveals features of a pathogenicity island. Two evolutionary lineages of this “high pathogenicity island” (HPI) can be distinguished on the basis of DNA sequence comparison: a Y. pestis group and a Y. enterocolitica group. In this study we demonstrate that the HPI of the Y. pestis evolutionary group is disseminated among species of the family Enterobacteriaceae which are pathogenic to humans. It prevails in enteroaggregativeEscherichia coli and in E. coli blood culture isolates (93 and 80%, respectively), but is rarely found in enteropathogenic E. coli, enteroinvasive E. coli, and enterotoxigenic E. coli isolates. In contrast, the HPI was absent from enterohemorrhagic E. coli, Shigella, and Salmonella entericastrains investigated. Polypeptides encoded by the fyuA,irp1, and irp2 genes located on the HPI could be detected in E. coli strains pathogenic to humans. However, these E. coli strains showed a reduced sensitivity to the bacteriocin pesticin, whose uptake is mediated by the FyuA receptor. Escherichia strains do not possess thehms gene locus thought to be a part of the HPI of Y. pestis. Deletions of the fyuA-irp gene cluster affecting solely the fyuA part of the HPI were identified in 3% of the E. coli strains tested. These results suggest horizontal transfer of the HPI between Y. pestis and some pathogenic E. coli strains.

Molecular Mechanism Of Regulation Of Extramedullary Infiltration In AML1/ETO Positive Acute Myeloid Leukemia By APP/ERK/MMP-2

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3769-3769
Author(s):  
Guopan Yu ◽  
Fan Yi Meng ◽  
Ling Jiang ◽  
Changxin Yin ◽  
Zhixiang Wang ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Myeloid Leukemia ◽  
Molecular Mechanism ◽  
Myeloid Leukemia ◽  
High Expression ◽  
Control Group ◽  
Expression Levels ◽  
High Expression Group ◽  
App Gene ◽  
Acute Myeloid

Abstract Amyloid precursor protein (APP) has been reported to be highly expressed in AML1/ETO positive acute myeloid leukemia (AML1/ETO+ AML), and we found it express even higher in those with extramedullary infiltration in our previous study. But it’s still unknown what role APP plays and how it works in AML1/ETO+ AML. This study was designed to investigate the effect of APP gene on the prognosis and its molecular mechanism of extramedullary infiltration in the patients with AML1/ETO+ AML. 44 cases of AML1/ETO+ AML patients with median age of 29 years old, who were admitted to our hospital from February, 2006 to February, 2012 and made the diagnosis according to WHO2008 diagnosis standard, and had completed conventional induction, consolidation and intensive therapy, were investigated in this study. They were divided into high expression group (n=22) and low one (n=22) according to APP mRNA median expression level from bone marrow cells before the first chemotherapy by QRT-PCR. Some of bone marrow samples were checked by Western Blot, and 5 biopsy specimens from extramedullary infiltration were tested by APP antibody immunohistochemistry staining. Incidence of extramedullary leukemia (EML), complete response (CR), overall survival (OS), and recurrence free survival (RFS) was differentiated between the two groups. Differences of cell ultrastructure, migration, proliferation, apoptosis and expression of ERK, MMP-2, MMP-9 and CXCR4 were studied on Kasumi-1 cell line between wild, negative control (NC) and si-APP group in which the expression levels of APP gene were down regulated with application of siRNA technology.Çå The incidence of EML was significantly different (45.5% versus 9.1%) in the two groups (P=0.007) and it was positively correlative with the expression levels of APP mRNA (rp=0.435, P=0.004). Extramedullary infiltration site also showed high expression of APP by immunohistochemistry, while the control group was negative. Not only CR rate after two courses of chemotherapy, but also OS and RFS with median follow-up of 28(4-70) months, of high expression group was all significantly lower than that of low expression group (Table 1). Compared with the wild and NC group, cell apoptosis of si-APP group was significantly increased (12.33 ± 0.75 vs 19.80 ± 1.51, P=0.000); the number of microvilli on the surface of the cell membrane significantly reduced; the ability of the cell migration by Tanswell chamber migration assay significantly decreased (P=0.004); and expression of P-ERK, c-MYC, MMP-2 decreased significantly which was confirmed by ERK and c-MYC blocker treatment (Figure 1). In sum, incidence of EML is significantly higher and the prognosis is poor in the patients with AML1/ETO+ AML with high expression of APP gene. We first describe that APP gene may mediate AML1/ETO+ leukemia cells in the development of extramedullary infiltration by up-regulation of the ERK/MMP-2 pathway. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Attenuation of Cardiac Ischaemia-reperfusion Injury by Treatment with Hydrogen-rich Water

2019 ◽  
Vol 19 (4) ◽  
pp. 294-302 ◽  
Author(s):  
Xiangzi Li ◽  
Liangtong Li ◽  
Xuanchen Liu ◽  
Jiawen Wu ◽  
Xiaoyu Sun ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Left Ventricular ◽  
Control Group ◽  
Tunel Staining ◽  
Ischaemia Reperfusion Injury ◽  
Expression Levels ◽  
Water Group ◽  
Ischaemia Reperfusion ◽  
Chip Technology ◽  
Male Wistar Rats

Background: Hydrogen has been shown to exert a bioactive effect on the myocardium. This study examined the signalling pathways for hydrogen attenuating ischaemia-reperfusion injury. Methods: In total, 20 male Wistar rats were evaluated for the effects of hydrogen-rich water on ischaemia-reperfusion in hearts. Left ventricular tissue was taken for screening and analysis of active protein factors by protein chip technology. The enrichment of the KEGG pathway was obtained by using the Gene Ontology (GO) enrichment principle. The expression of JAK2, STAT1, STAT3, p-STAT1, p-JAK2, p-STAT3 in rat myocardium was detected by Western blot analysis and immunohistochemistry. The apoptosis rates of the control and hydrogen-rich water groups were detected by TUNEL staining. Results: The expression levels of 25 proteins, including five transduction pathways, were downregulated in the hydrogen-rich water group. The expression levels of p- JAK2/JAK2, p-STAT3/STAT3 were upregulated in the hydrogen-rich water group compared with the control group, and p-STAT1/STAT1 was downregulated in the hydrogen-rich water group compared with the control group. Furthermore, the apoptosis rate was significantly decreased in the hydrogen-rich water group, as well. Conclusion: Hydrogen-rich water may inhibit the apoptosis of cardiomyocytes after ischaemia-reperfusion by upregulating the expression of the JAK2-STAT3 signalling pathway, which reduces ischaemia-reperfusion injury.

Molecular Mechanism of the Cell Membrane Pore Formation Induced by Bubble Stable Cavitation

2018 ◽  
Vol 123 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Viet Hoang Man ◽  
Phan Minh Truong ◽  
Mai Suan Li ◽  
Junmei Wang ◽  
Nguyen-Thi Van-Oanh ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Molecular Mechanism ◽  
Pore Formation ◽  
Membrane Pore

scholarly journals A Genomic Island, Termed High-Pathogenicity Island, Is Present in Certain Non-O157 Shiga Toxin-Producing Escherichia coli Clonal Lineages

1999 ◽  
Vol 67 (11) ◽  
pp. 5994-6001 ◽  
Author(s):  
H. Karch ◽  
S. Schubert ◽  
D. Zhang ◽  
W. Zhang ◽  
H. Schmidt ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Wide Spectrum ◽  
Pathogenicity Island ◽  
Immunoblot Analysis ◽  
Ecological Niches ◽  
Pathogenic Potential ◽  
Integrase Gene ◽  
E Coli ◽  
High Pathogenicity

ABSTRACT Shiga toxin-producing Escherichia coli (STEC) strains cause a wide spectrum of diseases in humans. In this study, we tested 206 STEC strains isolated from patients for potential virulence genes including stx, eae, and enterohemorrhagicE. coli hly. In addition, all strains were examined for the presence of another genetic element, the high-pathogenicity island (HPI). The HPI was first described in pathogenic Yersiniaspecies and encodes the pesticin receptor FyuA and the siderophore yersiniabactin. The HPI was found in the genome of distinct clonal lineages of STEC, including all 31 eae-positive O26:H11/H− strains and 7 of 12 eae-negative O128:H2/H− strains. In total, the HPI was found in 56 (27.2%) of 206 STEC strains. However, it was absent from the genome of all 37 O157:H7/H−, 14 O111:H−, 13 O103:H2, and 13 O145:H− STEC isolates, all of which were positive for eae. Polypeptides encoded by the fyuA gene located on the HPI could be detected by using immunoblot analysis in most of the HPI-positive STEC strains, suggesting the presence of a functional yersiniabactin system. The HPI in STEC was located next to the tRNA gene asnT. In contrast to the HPI of other pathogenic enterobacteria, the HPI of O26 STEC strains shows a deletion at its left junction, leading to a truncated integrase geneint. We conclude from this study that theYersinia HPI is disseminated among certain clonal subgroups of STEC strains. The hypothesis that the HPI in STEC contributes to the fitness of the strains in certain ecological niches rather than to their pathogenic potential is discussed.

Trimetazidine Pretreatment Inhibits Myocardial Apoptosis and Improves Cardiac Function in a Swine Model of Coronary Microembolization

Cardiology ◽  
2015 ◽  
Vol 130 (2) ◽  
pp. 130-136 ◽  
Author(s):  
Yang-Chun Liu ◽  
Lang Li ◽  
Qiang Su ◽  
Tao Liu ◽  
Zhong-li Tang
Keyword(s):  
Cardiac Function ◽  
Control Group ◽  
Tunel Staining ◽  
Swine Model ◽  
Caspase 9 ◽  
Apoptotic Pathway ◽  
Expression Levels ◽  
Coronary Microembolization ◽  
Myocardial Apoptosis ◽  
Operation Results

Objective: Trimetazidine (TMZ) is a well-known anti-ischemic agent; however, its efficacy and mechanism of cardioprotection on coronary microembolization (CME) are largely unknown. The present study was undertaken to determine whether TMZ pretreatment could attenuate myocardial apoptosis and improve cardiac function in a swine model of CME. Methods: Fifteen swine were randomly and equally divided into a sham-operated (control) group, CME group and CME plus TMZ (TMZ) group. CME was induced by injecting inert plastic microspheres (42 μm in diameter) into the left anterior descending artery. For the control group, the same dose of normal saline was substituted for the microspheres, and the TMZ group was pretreated with TMZ 30 min before microsphere injection. Cardiac function was assessed by echocardiography, myocardial apoptosis was detected by TUNEL staining, and the expression levels of cleaved caspase-9/3 were measured by Western blot 12 h after operation. Results: Compared to the control group, cardiac function in the CME group was significantly decreased (p < 0.05); however, TMZ pretreatment showed significantly improved cardiac function as compared to the CME group (p < 0.05). The myocardial apoptotic rate and the expression levels of cleaved caspase-9/3 increased remarkably in CME group as compared with the control group (p < 0.001). Again, TMZ pretreatment significantly reduced the apoptotic rate and also the expression levels of cleaved caspase-9/3 (p < 0.001). Conclusion: The present study demonstrated that TMZ pretreatment could significantly inhibit CME-induced myocardial apoptosis and improve cardiac function, and that the cardioprotective effect appeared to be mediated by the blockade of the mitochondrial apoptotic pathway. These results emphasize the importance of TMZ pretreatment in the therapy of CME-induced myocardial injury.

scholarly journals Intraperitoneal injection of ketamine enhances apoptosis in urothelium via autophagy in rats

2020 ◽  
Vol 18 ◽  
pp. 205873922093566
Author(s):  
Liqin Wei ◽  
Jitao Wu ◽  
Danxia Li ◽  
Zhengfei Shan
Keyword(s):  
Treatment Time ◽  
Control Group ◽  
Tunel Staining ◽  
High Dose ◽  
Sprague Dawley ◽  
Control Groups ◽  
Bladder Epithelium ◽  
Bladder Tissue ◽  
Expression Levels ◽  
Sprague Dawley Rats

Ketamine abusing is associated with ulcerative cystitis, but the mechanisms remain unclear. This study aimed to investigate the existence of ketamine-induced symptom in a rat model and evaluate the underlining mechanisms. Sprague-Dawley rats were chosen and randomly divided into 12 groups (n = 8), such as the control group, low dose of ketamine (10 mg/kg/day), middle dose of ketamine (30 mg/kg/day) and high dose of ketamine (50 mg/kg/day) groups. The experimental groups were administrated ketamine i.p. daily, whereas the control groups were administrated with saline. After 1, 3, and 6 months of treatment, the bladder tissues were collected. Haematoxylin and eosin (HE) staining and a transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay were used to evaluate the bladder epithelium pathology and urothelial apoptosis, respectively. The protein expression levels of LC3, p62, Beclin1 were assessed by Western blotting. HE staining results of the experimental rats showed the bladder tissue denudation of the urothelial epithelium with edema and congestion compared with the control groups. TUNEL staining showed a significantly higher number of apoptotic cells in experimental groups than in the control groups. The protein LC3 and Beclin1 had significantly higher levels compared with control groups. The protein p62 had lower levels compared with control groups. The expression levels correlated with contraction of ketamine and treatment time. HE staining, TUNEL staining and Western blot results showed dose-dependent, time-dependent autophage in ketamine-treated rats. All the results suggested that autophagy proteins might be involved in inflammatory response in rats.

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