Defective interleukin-1-induced ACTH release in cholestatic rats: impaired hypothalamic PGE2 release

1995 ◽  
Vol 268 (3) ◽  
pp. G404-G409 ◽  
Author(s):  
M. G. Swain ◽  
M. Maric ◽  
L. Carter

A complete regulatory loop exists between the immune and neuroendocrine systems. Proinflammatory mediators such as endotoxin (lipopolysaccharide) and interleukin-1 (IL-1) are capable of activating the hypothalamic-pituitary-adrenal (HPA) axis at the hypothalamic level, presumably by inducing the synthesis of prostaglandins. We have recently identified abnormalities in the stress-induced activation of the HPA axis in cholestatic rats. Therefore, in rats with cholestasis due to bile duct resection and sham-resected controls, we studied alterations in proinflammatory mediator-induced activation of the HPA axis and documented the role of alterations in hypothalamic prostaglandin synthesis in these abnormalities. Systemic administration of endotoxin and IL-1 resulted in a significant attenuation of adrenocorticotropic hormone (ACTH) release into plasma in bile duct-resected compared with sham-resected animals. This suppression of endotoxin- or IL-1-induced ACTH release in bile duct-resected rats was associated with a complete absence of IL-1-induced hypothalamic release of prostaglandin E2 (PGE2) in vitro in these animals. In contrast, sham-resected rats exhibited a 70% increase in hypothalamic PGE2 secretion in vitro in response to IL-1. However, bile duct-resected rats exhibited HPA axis activation similar to that of sham-resected animals in response to intracerebroventricularly infused PGE2. Therefore, cholestasis in the rat is associated with an attenuation of central activation of the HPA axis by proinflammatory mediators that appears to be mediated, at least in part, by defective IL-1-induced hypothalamic prostaglandin production.

1996 ◽  
Vol 271 (2) ◽  
pp. G275-G281 ◽  
Author(s):  
P. Montuschi ◽  
G. Tringali ◽  
A. Mirtella ◽  
L. Parente ◽  
E. Ragazzoni ◽  
...  

Interleukin-1 (IL-1) is known to regulate gastric functions via a central action at the hypothalamic level, and it has also been shown that this cytokine can directly modulate rat gastric motility. This study was conducted to determine whether IL-1 beta is produced and released by rat gastric fundi in vitro. IL-1 beta immunoreactivity was released in measurable amounts from explanted rat gastric tissue. This release was not affected by electrical stimulation of the gastric strips or by agents that induce IL-1 biosynthesis. It could be inhibited only by the glucocorticoid dexamethasone. Ex vivo experiments confirmed the inhibitory role of glucocorticoids and showed that IL-1 beta release can be inhibited by agents that reduce gastric acid secretion, suggesting that the latter might stimulate IL-1 beta synthesis and release. In light of the well-established gastroprotection exerted by IL-1, H(+)-induced IL-1 beta release might serve as a protection against mucosal injuries caused by acid secretion, and the inhibition of this release by glucocorticoids might be involved in the pathogenesis of gastric damage associated with severe stress or steroid therapy.


2021 ◽  
Vol 20 ◽  
pp. 153303382199528
Author(s):  
Qing Lv ◽  
Qinghua Xia ◽  
Anshu Li ◽  
Zhiyong Wang

This study was performed to investigate the role of interleukin-1 receptor accessory protein (IL1RAP) in stomach carcinoma in vitro and in vivo, determine whether IL1RAP knockdown could regulate the development of stomach carcinoma, and elucidate the relationship between IL1RAP knockdown and inflammation by tumor microenvironment-related inflammatory factors in stomach carcinoma. We first used TCGA and GEPIA systems to predict the potential function of IL1RAP. Second, western blot and RT-PCR were used to analyze the expression, or mRNA level, of IL1RAP at different tissue or cell lines. Third, the occurrence and development of stomach carcinoma in vitro and in vivo were observed by using IL1RAP knockdown lentivirus. Finally, the inflammation of stomach carcinoma in vitro and in vivo was observed. Results show that in GEPIA and TCGA systems, IL1RAP expression in STAD tumor tissue was higher than normal, and high expression of IL1RAP in STAD patients had a worse prognostic outcome. Besides, GSEA shown IL1RAP was negative correlation of apopopsis, TLR4 and NF-κB signaling pathway. We also predicted that IL1RAP may related to IL-1 s, IL-33, and IL-36 s in STAD. The IL1RAP expression and mRNA level in tumor, or MGC803, cells were increased. Furthermore, IL1RAP knockdown by lentivirus could inhibit stomach carcinoma development in vitro and in vivo through weakening tumor cell proliferation, migration, invasion, therefore reducing tumor volume, weight, and biomarker levels, and increasing apoptotic level. Finally, we found IL1RAP knockdown could increase inflammation of tumor microenvironment-related inflammatory factors of stomach carcinoma, in vitro and in vivo. Our study demonstrates that IL1RAP is possibly able to regulate inflammation and apoptosis in stomach carcinoma. Furthermore, TLR4, NF-κB, IL-1 s, IL-33, and IL-36 s maybe the downstream target factor of IL1RAP in inflammation. These results may provide a new strategy for stomach carcinoma development by regulating inflammation.


2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
S. Memmert ◽  
A. Damanaki ◽  
A. V. B. Nogueira ◽  
S. Eick ◽  
M. Nokhbehsaim ◽  
...  

Cathepsin S is a cysteine protease and regulator of autophagy with possible involvement in periodontitis. The objective of this study was to investigate whether cathepsin S is involved in the pathogenesis of periodontal diseases. Human periodontal fibroblasts were cultured under inflammatory and infectious conditions elicited by interleukin-1β and Fusobacterium nucleatum, respectively. An array-based approach was used to analyze differential expression of autophagy-associated genes. Cathepsin S was upregulated most strongly and thus further studied in vitro at gene and protein levels. In vivo, gingival tissue biopsies from rats with ligature-induced periodontitis and from periodontitis patients were also analyzed at transcriptional and protein levels. Multiple gene expression changes due to interleukin-1β and F. nucleatum were observed in vitro. Both stimulants caused a significant cathepsin S upregulation. A significantly elevated cathepsin S expression in gingival biopsies from rats with experimental periodontitis was found in vivo, as compared to that from control. Gingival biopsies from periodontitis patients showed a significantly higher cathepsin S expression than those from healthy gingiva. Our findings provide original evidence that cathepsin S is increased in periodontal cells and tissues under inflammatory and infectious conditions, suggesting a critical role of this autophagy-associated molecule in the pathogenesis of periodontitis.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Quanxin Ma ◽  
Kai Wang ◽  
Qinqin Yang ◽  
Shun Ping ◽  
Weichun Zhao ◽  
...  

Veronicastrum axillare is a traditional medical plant in China which is widely used in folk medicine due to its versatile biological activities, especially for its anti-inflammatory effects. However, the detailed mechanism underlying this action is not clear. Here, we studied the protective effects of V. axillare against acute lung injury (ALI), and we further explored the pharmacological mechanisms of this action. We found that pretreatment with V. axillare suppressed the release of proinflammatory cytokines in the serum of ALI mice. Histological analysis of lung tissue demonstrated that V. axillare inhibited LPS-induced lung injury, improved lung morphology, and reduced the activation of nuclear factor-κB (NF-κB) in the lungs. Furthermore, the anti-inflammatory actions of V. axillare were investigated in vitro. We observed that V. axillare suppressed the mRNA expression of interleukin-1β (IL-1β), IL-6, monocyte chemotactic protein-1 (MCP-1), cyclooxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α) in RAW264.7 cells challenged with LPS. Furthermore, pretreatment of V. axillare in vitro reduced the phosphorylation of p65 and IκB-α which is activated by LPS. In conclusion, our data firstly demonstrated that the anti-inflammatory effects of V. axillare against ALI were achieved through downregulation of the NF-κB signaling pathway, thereby reducing the production of inflammatory mediators.


2018 ◽  
Vol 215 (6) ◽  
pp. 1709-1727 ◽  
Author(s):  
Kelly Mitchell ◽  
Laura Barreyro ◽  
Tihomira I. Todorova ◽  
Samuel J. Taylor ◽  
Iléana Antony-Debré ◽  
...  

The surface molecule interleukin-1 receptor accessory protein (IL1RAP) is consistently overexpressed across multiple genetic subtypes of acute myeloid leukemia (AML) and other myeloid malignancies, including at the stem cell level, and is emerging as a novel therapeutic target. However, the cell-intrinsic functions of IL1RAP in AML cells are largely unknown. Here, we show that targeting of IL1RAP via RNA interference, genetic deletion, or antibodies inhibits AML pathogenesis in vitro and in vivo, without perturbing healthy hematopoietic function or viability. Furthermore, we found that the role of IL1RAP is not restricted to the IL-1 receptor pathway, but that IL1RAP physically interacts with and mediates signaling and pro-proliferative effects through FLT3 and c-KIT, two receptor tyrosine kinases with known key roles in AML pathogenesis. Our study provides a new mechanistic basis for the efficacy of IL1RAP targeting in AML and reveals a novel role for this protein in the pathogenesis of the disease.


2020 ◽  
Vol 40 (9) ◽  
pp. 2070-2083
Author(s):  
Lin-Lin Wei ◽  
Ning Ma ◽  
Kun-Yi Wu ◽  
Jia-Xing Wang ◽  
Teng-Yue Diao ◽  
...  

Objective: Emerging evidence suggests that C3aR (C3a anaphylatoxin receptor) signaling has protective roles in various inflammatory-related diseases. However, its role in atherosclerosis has been unknown. The purpose of the study was to investigate the possible protective role of C3aR in aortic atherosclerosis and explore molecular and cellular mechanisms involved in the protection. Approach and Results: C3ar −/− /Apoe −/− mice were generated by cross-breeding of atherosclerosis-prone Apoe −/− mice and C3ar −/− mice. C3ar −/− /Apoe −/− mice and Apoe −/− mice (as a control) underwent high-fat diet for 16 weeks were assessed for (1) atherosclerotic plaque burden, (2) aortic tissue inflammation, (3) recruitment of CD11b + leukocytes into atherosclerotic lesions, and (4) systemic inflammatory responses. Compared with Apoe −/− mice, C3ar −/− /Apoe −/− mice developed more severe atherosclerosis. In addition, C3ar −/− /Apoe −/− mice have increased local production of proinflammatory mediators (eg, CCL2 [chemokine (C-C motif) ligand 2], TNF [tumor necrosis factor]-α) and infiltration of monocyte/macrophage in aortic tissue, and their lesional macrophages displayed an M1-like phenotype. Local pathological changes were associated with enhanced systemic inflammatory responses (ie, elevated plasma levels of CCL2 and TNF-α, increased circulating inflammatory cells). In vitro analyses using peritoneal macrophages showed that C3a stimulation resulted in upregulation of M2-associated signaling and molecules, but suppression of M1-associated signaling and molecules, supporting the roles of C3a/C3aR axis in mediating anti-inflammatory response and promoting M2 macrophage polarization. Conclusions: Our findings demonstrate a protective role for C3aR in the development of atherosclerosis and suggest that C3aR confers the protection through C3a/C3aR axis–mediated negative regulation of proinflammatory responses and modulation of macrophage toward the anti-inflammatory phenotype.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Linh Le ◽  
Lingzi Niu ◽  
Matthew J. Barter ◽  
David A. Young ◽  
Tamas Dalmay ◽  
...  

AbstractMicroRNAs have been shown to play a role in cartilage development, homeostasis and breakdown during osteoarthritis. We previously identified miR-3085 in humans as a chondrocyte-selective microRNA, however it could not be detected by Northern blot. The aim of the current study was to prove that miR-3085 is a microRNA and to investigate the function of miR-3085 in signaling pathways relevant to cartilage homeostasis and osteoarthritis. Here, we confirm that miR-3085 is a microRNA and not another class of small RNA using (1) a pre-miR hairpin maturation assay, (2) expression levels in a Dicer null cell line, and (3) Ago2 pulldown. MicroRNA-3085-3p is expressed more highly in micromass than monolayer cultured chondrocytes. Transfection of miR-3085-3p into chondrocytes decreases expression of COL2A1 and ACAN, both of which are validated as direct targets of miR-3085-3p. Interleukin-1 induces the expression of miR-3085-3p, at least in part via NFκB. In a feed-forward mechanism, miR-3085-3p then potentiates NFκB signaling. However, at early time points after transfection, its action appears to be inhibitory. MyD88 has been shown to be a direct target of miR-3085-3p and may be responsible for the early inhibition of NFκB signaling. However, at later time points, MyD88 knockdown remains inhibitory and so other functions of miR-3085-3p are clearly dominant. TGFβ1 also induces the expression of miR-3085-3p, but in this instance, it exerts a feedback inhibition on signaling with SMAD3 and SMAD4 shown to be direct targets. This in vitro analysis shows that miR-3085-3p functions in chondrocytes to induce IL-1-signaling, reduce TGFβ1 signaling, and inhibit expression of matrix genes. These data suggest that miR-3085-3p has a role in chondrocyte function and could contribute to the process of osteoarthritis.


Nephrology ◽  
2002 ◽  
Vol 7 (3) ◽  
pp. 136-144
Author(s):  
Kazunori Takazoe ◽  
Rita Foti ◽  
Lynette A Hurst ◽  
Hui Y Lan ◽  
Robert C Atkins ◽  
...  

1992 ◽  
Vol 1 (5) ◽  
pp. 347-353 ◽  
Author(s):  
Andrew C. Issekutz ◽  
Nancy Lopes ◽  
Thomas B. Issekutz

The cytokines IL-1 and TNF-α are involved in inflammation and their production is stimulated by various agents, especially endotoxin (LPS). Here, using the human IL-1 receptor antagonist (IL-1RA) and a new monoclonal antibody (mAb 7F11) to rabbit TNF, the role of endogenous IL-l and TNF production in acute (3h) leukocyte (PMNL) recruitment to dermal inflammation in rabbits has been studied. IL-1RA inhibited by 27% the PMNL accumulation in reactions induced by killed Escherichia coli (p < 0.05) but not by LPS. The monoclonal antibody to TNF inhibited by 27% and 38% (p < 0.002) the PMNL accumulation in LPS and E. coli reactions respectively, but a combination of the mAb with IL-1RA was not more effective. Treatment of human umbilical vein endothelium with LPS for 3 h activated endothelium to induce PMNL transendothelial migration in vitro, which was not inhibited by IL-1RA, antibody to TNF-α, IL-1 or to IL-8. In conclusion, TNF and IL-1 may partially mediate acute PMNL infiltration in vivo to LPS and Gram negative bacteria, but there is a major IL-1/TNF independent mechanism, at least in dermal inflammation, which may be due to direct LPS activation of the microvasculature or perhaps the generation of cytokines other than IL-1 and TNF.


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