scholarly journals RORA regulates neutrophil migration and activation in zebrafish

2021 ◽  
Author(s):  
Alan Y. Hsu ◽  
Tianqi Wang ◽  
Ramizah Syahirah ◽  
Sheng Liu ◽  
Kailing Li ◽  
...  
Keyword(s):  
Tissue Injury ◽  
Neutrophil Migration ◽  
Dominant Negative ◽  
Orphan Receptor ◽  
Human Neutrophils ◽  
Transcriptional Level ◽  
Protein Coding ◽  
Dominant Negative Form ◽  
Microbial Defense ◽  
Increased Susceptibility

AbstractNeutrophil migration and activation are essential for defense against pathogens. However, this process may also lead to collateral tissue injury. We used microRNA overexpression as a platform and discovered protein-coding genes that regulate neutrophil migration. Here we show that miR-99 decreased the chemotaxis of zebrafish neutrophils and human neutrophil-like cells. In zebrafish neutrophils, miR-99 directly targets the transcriptional factor RAR-related orphan receptor alpha (roraa). Inhibiting RORα, but not the closely related RORγ, reduced chemotaxis of zebrafish and primary human neutrophils without causing cell death, and increased susceptibility of zebrafish to bacterial infection. Expressing a dominant-negative form of Rorα or disrupting the roraa locus specifically in zebrafish neutrophils reduced cell migration. At the transcriptional level, RORα regulates transmembrane signaling receptor activity and protein phosphorylation pathways. Our results, therefore, reveal previously unknown functions of miR- 99 and RORα in regulating neutrophil migration and anti-microbial defense.

scholarly journals Phenotypical microRNA screen reveals a noncanonical role of CDK2 in regulating neutrophil migration

2019 ◽  
Author(s):  
A.Y. Hsu ◽  
D. Wang ◽  
S. Liu ◽  
J. Lu ◽  
R. Syahirah ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Systemic Inflammation ◽  
Cell Cycle Progression ◽  
Inflammatory Responses ◽  
Tissue Injury ◽  
Neutrophil Migration ◽  
Human Neutrophils ◽  
Neutrophil Chemotaxis ◽  
Cycle Progression

AbstractNeutrophil migration is essential for inflammatory responses to kill pathogens, however it also causes tissue injury. To discover novel therapeutic targets that modulate neutrophil migration, we performed a neutrophil-specific microRNA overexpression screen in zebrafish, and identified eight microRNAs as potent suppressors of neutrophil migration. Among those,miR-199decreases neutrophil chemotaxis in zebrafish and human neutrophil-like cells. Intriguingly, in terminally differentiated neutrophils,miR-199alters the cell cycle-related pathways and directly suppressescyclin-dependent kinase 2(cdk2), whose known activity is restricted to cell cycle progression and cell differentiation. Inhibiting CDK2, but not DNA replication, disrupts cell polarity and chemotaxis of zebrafish neutrophils. Chemotaxis of primary human neutrophils are also reduced by CDK2 inhibition. Furthermore,miR-199overexpression or CDK2 inhibition significantly improves the outcome of lethal systemic inflammation challenges in zebrafish. Together, our results reveal previously unknown functions ofmiR-199and CDK2 in regulating neutrophil migration and provide new directions in alleviating systemic inflammation.One Sentence SummarymiR-199directly suppressescdk2expression, neutrophil chemotaxis and systemic inflammation.

scholarly journals Progesterone Stimulates Adipocyte Determination and Differentiation 1/Sterol Regulatory Element-binding Protein 1c Gene Expression

2001 ◽  
Vol 276 (15) ◽  
pp. 11512-11516 ◽  
Author(s):  
Danièle Lacasa ◽  
Xavier Le Liepvre ◽  
Pascal Ferre ◽  
Isabelle Dugail
Keyword(s):  
Adipose Tissue ◽  
Fatty Acid Synthase ◽  
Binding Protein ◽  
Regulatory Element ◽  
Cancer Cell Line ◽  
Dominant Negative ◽  
Transcriptional Level ◽  
Dominant Negative Form ◽  
Element Binding Protein ◽  
Sterol Regulatory Element

Fatty acid synthase (FAS), a nutritionally regulated lipogenic enzyme, is transcriptionally controlled by ADD1/SREBP1c (adipocyte determination and differentiation 1/sterol regulatory element-binding protein 1c), through insulin-mediated stimulation of ADD1/SREBP1c expression. Progesterone exerts lipogenic effects on adipocytes, and FAS is highly induced in breast tumor cell lines upon progesterone treatment. We show here that progesterone up-regulates ADD1/SREBP1c expression in the MCF7 breast cancer cell line and the primary cultured preadipocyte from rat parametrial adipose tissue. In MCF7, progesterone induced ADD1/SREBP1c and Metallothionein II (a well known progesterone-regulated gene) mRNAs, with comparable potency. In preadipocytes, progesterone increased ADD1/SREBP1c mRNA dose-dependently, but not SREBP1a or SREBP2. Run-on experiments demonstrated that progesterone action on ADD1/SREBP1c was primarily at the transcriptional level. The membrane-bound and mature nuclear forms of ADD1/SREBP1 protein accumulated in preadipocytes cultured with progesterone, and FAS induction could be abolished by adenovirus-mediated overexpression of a dominant negative form of ADD1/SREBP1 in these cells. Finally, in the presence of insulin, progesterone was unable to up-regulate ADD1/SREBP1c mRNA in preadipocytes, whereas its effect was restored after 24 h of insulin deprivation. Together these results demonstrate that ADD1/SREBP1c is controlled by progesterone, which, like insulin, acts by increasing ADD1/SREBP1c gene transcription. This provides a potential mechanism for the lipogenic actions of progesterone on adipose tissue.

scholarly journals Phenotypical microRNA screen reveals a noncanonical role of CDK2 in regulating neutrophil migration

2019 ◽  
Vol 116 (37) ◽  
pp. 18561-18570 ◽  
Author(s):  
Alan Y. Hsu ◽  
Decheng Wang ◽  
Sheng Liu ◽  
Justice Lu ◽  
Ramizah Syahirah ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Systemic Inflammation ◽  
Human Neutrophil ◽  
Cell Cycle Progression ◽  
Inflammatory Responses ◽  
Tissue Injury ◽  
Neutrophil Migration ◽  
Formyl Peptide Receptor ◽  
Human Neutrophils ◽  
Formyl Peptide

Neutrophil migration is essential for inflammatory responses to kill pathogens; however, excessive neutrophilic inflammation also leads to tissue injury and adverse effects. To discover novel therapeutic targets that modulate neutrophil migration, we performed a neutrophil-specific microRNA (miRNA) overexpression screen in zebrafish and identified 8 miRNAs as potent suppressors of neutrophil migration. Among those,miR-199decreases neutrophil chemotaxis in zebrafish and human neutrophil-like cells. Intriguingly, in terminally differentiated neutrophils,miR-199alters the cell cycle-related pathways and directly suppresses cyclin-dependent kinase 2 (Cdk2), whose known activity is restricted to cell cycle progression and cell differentiation. Inhibiting Cdk2, but not DNA replication, disrupts cell polarity and chemotaxis of zebrafish neutrophils without inducing cell death. Human neutrophil-like cells deficient in CDK2 fail to polarize and display altered signaling downstream of the formyl peptide receptor. Chemotaxis of primary human neutrophils is also reduced upon CDK2 inhibition. Furthermore,miR-199overexpression or CDK2 inhibition significantly improves the outcome of lethal systemic inflammation challenges in zebrafish. Our results therefore reveal previously unknown functions ofmiR-199and CDK2 in regulating neutrophil migration and provide directions in alleviating systemic inflammation.

Increased susceptibility to ischemia‐induced brain damage in transgenic mice overexpressing a dominant negative form of SHP2

2000 ◽  
Vol 14 (13) ◽  
pp. 1965-1973 ◽  
Author(s):  
Yoko Aoki ◽  
Zhihong Huang ◽  
Sunu S. Thomas ◽  
Pradeep G. Bhide ◽  
Ivana Huang ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Brain Damage ◽  
Dominant Negative ◽  
Dominant Negative Form ◽  
Increased Susceptibility ◽  
Negative Form

The Inhibitory Effect of Heparin and Related Glycosaminoglycans on Neutrophil Chemotaxis

1984 ◽  
Vol 52 (02) ◽  
pp. 134-137 ◽  
Author(s):  
Yaacov Matzner ◽  
Gerard Marx ◽  
Ruth Drexler ◽  
Amiram Eldor
Keyword(s):  
Specific Binding ◽  
Anticoagulant Activity ◽  
Neutrophil Migration ◽  
Inhibitory Effect ◽  
Chemotactic Factor ◽  
Human Neutrophils ◽  
Boyden Chamber ◽  
Neutrophil Chemotaxis ◽  
Inhibitory Effects ◽  
Chemotactic Factors

SummaryClinical observations have shown that heparin has antiinflammatory activities. The effect of heparin on neutrophil chemotaxis was evaluated in vitro in the Boyden Chamber. This method enabled differentiation between the direct effects of heparin on neutrophil migration and locomotion, and its effects on chemotactic factors. Heparin inhibited both the random migration and directed locomotion of human neutrophils toward zymosan-activated serum (ZAS) and F-met-leu-phe (FMLP). Inhibition was found to be dependent on the concentrations of the heparin and of the chemotactic factors. No specific binding of heparin to the neutrophils could be demonstrated, and heparin’s inhibitory effects were eliminated by simple washing of the cells. When added directly to the chamber containing chemotactic factor, heparin inhibited the chemotactic activity of ZAS but not that of FMLP, suggesting a direct inhibitory effect against C5a, the principal chemotactic factor in ZAS.Experiments performed with low-molecular-weight heparin, N-desulfated heparin, dextran sulfate, chondroitin sulfate and dextran indicated that the inhibitory effects of heparin on neutrophil chemotaxis are not related to its anticoagulant activity, but probably depend on the degree of sulfation of the heparin molecule.

THE ROLE OF MYELOPEROXIDASE AND NEUTROPHIL EXTRACELLULAR TRAPS IN THE PATHOGENESIS OF INFLAMMATORY BOWEL DISEASE

2021 ◽  
Vol 27 (Supplement_1) ◽  
pp. S4-S4
Author(s):  
Belal Chami ◽  
Gulfam Ahmad ◽  
Angie Schroder ◽  
Patrick San Gabriel ◽  
Paul Witting
Keyword(s):  
Disease Severity ◽  
Hypochlorous Acid ◽  
Tissue Injury ◽  
Activity Index ◽  
Critical Role ◽  
Neutrophil Migration ◽  
Sodium Sulphate ◽  
Host Tissue ◽  
Neutrophil Extracellular Trap

Abstract Neutrophils are short-lived immune cells that represent the major cell type recruited to the inflamed bowel releasing their azurophilic granules containing enzymes myeloperoxidase (MPO). Fecal and serum MPO levels has previously been shown to correlate to disease severity in IBD patients. MPO, in the presence of H2O2 and free Cl- undergoes a halogenation cycle, yielding the two-electron oxidant, hypochlorous acid (HOCl) - a potent bactericidal agent. However, chronic intestinal exposure to MPO/HOCl due to perpetual inflammation may cause secondary host-tissue injury and cell death. Neutrophil Extracellular Trap (NET)osis is a specialised form of neutrophil death where MPO is entrapped in a DNA scaffold and continues to elicit HOCl activity and may further contribute to host-tissue injury. We investigated the presence of NETs in surgically excised ileum samples from CD and healthy patients using advanced confocal microscopic techniques and found MPO, Neutrophil Elastase (NE) and Citrullinated Histone h3 (CitH3) - critical components of NET formation, individually positively correlate to the severity of histopathological intestinal injury. Furthermore, multiplex Opal™ IHC performed using LMS880 Airyscan-moduled microscopy with z-stacking revealed colocalization of NE, MPO, CitH3 and DAPI indicating the extensive presence of NETs in severely affected CD tissue. Using two pharmacological inhibitors of MPO in a dextran sodium sulphate (DSS) model of murine colitis, we demonstrated the pathological role of MPO in experimental colitis. MPO inhibitors, TEMPOL and AZD3241 delivered via daily i.p significantly rescued the course of colitis by abrogating clinical indices including body weight loss, disease activity index, inhibiting serum peroxidation, and preserving colon length, while significantly mitigating histoarchitectural damage associated with DSS-induced colitis. We also showed that MPO inhibition decreased neutrophil migration to the gut, suggesting MPO may play a role in perpetuating the inflammatory cell by further recruiting cells to the inflamed gut. Collectively, we have shown for the first time that MPO is not only an important clinical marker of disease severity but may also play a critical role in perpetuating host-tissue damage and inflammation.

scholarly journals Intestinal Apolipoprotein A-IV Gene Transcription Is Controlled by Two Hormone-Responsive Elements: A Role for Hepatic Nuclear Factor-4 Isoforms

2005 ◽  
Vol 19 (9) ◽  
pp. 2320-2334 ◽  
Author(s):  
Amena Archer ◽  
Dominique Sauvaget ◽  
Valérie Chauffeton ◽  
Pierre-Etienne Bouchet ◽  
Jean Chambaz ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transgenic Mice ◽  
Distal Region ◽  
Proximal Region ◽  
Dominant Negative ◽  
Specific Expression ◽  
Nuclear Factors ◽  
Dominant Negative Form ◽  
Responsive Element ◽  
Hormone Responsive Element

Abstract In the small intestine, the expression of the apolipoprotein (apo) C-III and A-IV genes is restricted to the enterocytes of the villi. We have previously shown that, in transgenic mice, specific expression of the human apo C-III requires a hormone-responsive element (HRE) located in the distal region of the human apoA-IV promoter. This HRE binds the hepatic nuclear factors (HNF)-4α and γ. Here, intraduodenal injections in mice and infections of human enterocytic Caco-2/TC7 cells with an adenovirus expressing a dominant-negative form of HNF-4α repress the expression of the apoA-IV gene, demonstrating that HNF-4 controls the apoA-IV gene expression in enterocytes. We show that HNF-4α and γ functionally interact with a second HRE present in the proximal region of the human apoA-IV promoter. New sets of transgenic mice expressing mutated forms of the promoter, combined with the human apo C-III enhancer, demonstrate that, whereas a single HRE is sufficient to reproduce the physiological cephalo-caudal gradient of apoA-IV gene expression, both HREs are required for expression that is restricted to villi. The combination of multiple HREs may specifically recruit regulatory complexes associating HNF-4 and either coactivators in villi or corepressors in crypts.

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