scholarly journals A Novel OGR1 (GPR68) Inhibitor Attenuates Inflammation in Murine Models of Colitis

2021 ◽  
pp. 1-14
Author(s):  
Cheryl de Vallière ◽  
Katharina Bäbler ◽  
Philipp Busenhart ◽  
Marlene Schwarzfischer ◽  
Chiaki Maeyashiki ◽  
...  

<b><i>Background and Aims:</i></b> Local extracellular acidification is associated with several conditions, such as ischemia, cancer, metabolic disease, respiratory diseases, and inflammatory bowel disease (IBD). Several recent studies reported a link between IBD and a family of pH-sensing G protein-coupled receptors. Our previous studies point to an essential role for OGR1 (GPR68) in the modulation of intestinal inflammation and fibrosis. In the current study, we evaluated the effects of a novel OGR1 inhibitor in murine models of colitis. <b><i>Methods:</i></b> The effects of a novel small-molecule OGR1 inhibitor were assessed in the acute and chronic dextran sulfate sodium (DSS) murine models of colitis. Macroscopic disease indicators of intestinal inflammation were evaluated, and epithelial damage and immune cell infiltration and proliferation were assessed by immunohistochemistry. <b><i>Results:</i></b> The OGR1 inhibitor ameliorated clinical parameters in acute and chronic DSS-induced colitis. In mice treated with the OGR1 inhibitor, endoscopy showed no thickening and normal vascularity, while fibrin was not detected. Histopathological findings revealed a decrease in severity of colonic inflammation in the OGR1 inhibitor group when compared to vehicle-DSS controls. In OGR1 inhibitor-treated mice, staining for the macrophage marker F4/80 and cellular proliferation marker Ki-67 revealed a reduction of infiltrating macrophages and slightly enhanced cell proliferation, respectively. This was accompanied by a reduction in pro-inflammatory cytokines, TNF and IL-6, and the fibrosis marker TGF-β1. <b><i>Conclusion:</i></b> This is the first report providing evidence that a pharmacological inhibition of OGR1 has a therapeutic effect in murine colitis models. Our data suggest that targeting proton-sensing OGR1 using specific small-molecule inhibitors may be a novel therapeutic approach for the treatment of IBD.

2019 ◽  
Author(s):  
Edward J. Sanderlin ◽  
Mona Marie ◽  
Juraj Velcicky ◽  
Pius Loetscher ◽  
Li V. Yang

AbstractInflammatory bowel disease (IBD) is characterized by chronic, recurring inflammation of the digestive tract. Current therapeutic approaches are limited and include biologics and steroids such as anti-TNFα monoclonal antibodies and corticosteroids, respectively. Significant adverse drug effects can occur for chronic usage and include increased risk of infection in some patients. GPR4, a pH-sensing G protein-coupled receptor, has recently emerged as a potential therapeutic target for intestinal inflammation. We have assessed the effects of a GPR4 antagonist, 2-(4-((2-Ethyl-5,7-dimethylpyrazolo[1,5-a]pyrimidin-3-yl)methyl)phenyl)-5-(piperidin-4-yl)-1,3,4-oxadiazole (GPR4 antagonist 13, also known as NE 52-QQ57) in the dextran sulfate sodium (DSS)-induced acute colitis mouse model. The GPR4 antagonist 13 inhibited intestinal inflammation. The clinical parameters such as body weight loss and fecal score were reduced in the GPR4 antagonist 13 treatment group compared to vehicle control. Macroscopic disease indicators such as colon shortening, splenic expansion, and mesenteric lymph node enlargement were all reduced in severity in the GPR4 antagonist 13 treated mice. Histopathological features of active colitis were alleviated in GPR4 antagonist 13 treatment groups compared to vehicle control. Finally, inflammatory gene expression in the colon tissues and vascular adhesion molecule expression in the intestinal endothelia were attenuated by GPR4 antagonist 13. Our results indicate that GPR4 antagonist 13 provides a protective effect in the DSS-induced acute colitis mouse model, and inhibition of GPR4 can be explored as a novel anti-inflammatory approach.


Medicina ◽  
2021 ◽  
Vol 57 (6) ◽  
pp. 607
Author(s):  
Rudolfs Janis Viksne ◽  
Gunta Sumeraga ◽  
Mara Pilmane

Background and Objectives: Chronic rhinosinusitis (CRS) is a condition that affects as much as 10.9% of the population and, along with presence of nasal polyps, is associated with significant morbidity and decreased quality of life. Studies on molecular pathways that have been activated in nasal polyp tissue are mainly based on cytokine concentration detection. Therefore, our aim is to investigate the complex appearance, relative distribution and interlinks of IL-1, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 and Ki 67 in chronic rhinosinusitis with nasal polyps (CRSwNP) affected human nasal mucosa. Materials and Methods: Samples of nasal polyps were obtained from 12 patients with previously diagnosed CRSwNP and no prior surgery. Control group consisted of samples from 17 otherwise healthy individuals with isolated nasal septum deviation. Tissues were stained for IL-1, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 and Ki67 immunohistochemically. Non-parametric statistic, Mann–Whitney U test and Spearman’s rank correlation coefficient were used. Results: All factors, except connective tissue cytokine IL-10 and proliferation marker Ki-67, had increased presence in connective tissue and decreased presence in epithelium of nasal polyps when compared to controls. Very strong and strong positive correlations between factors were observed. Conclusions: Decreased appearance of IL-1α, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12 positive structures in the nasal epithelium with selective increase of IL-1α and IL-12 in nasal subepithelial connective tissue characterize the cytokine endotype with dysfunctional epithelial barrier and local stimulation of immune response in the connective tissue in case of chronic rhinosinusitis with polyps. Decrease of IL-6 in both—epithelium and connective tissue with strong correlation between it and IL-7 and IL-10 in connective tissue suggests significant stimulation of this regulatory cytokine and, possibly, the important role in pathogenesis of the development in nasal polyps. Correlations between Ki67 and cytokines indicate possible involvement of IL-4, IL-7 and IL-12 in regulation of cellular proliferation.


Cancers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 56
Author(s):  
Allison A. Fitzgerald ◽  
Eric Li ◽  
Louis M. Weiner

Cancer immunotherapy has revolutionized cancer treatment, spurring extensive investigation into cancer immunology and how to exploit this biology for therapeutic benefit. Current methods to investigate cancer-immune cell interactions and develop novel drug therapies rely on either two-dimensional (2D) culture systems or murine models. However, three-dimensional (3D) culture systems provide a potentially superior alternative model to both 2D and murine approaches. As opposed to 2D models, 3D models are more physiologically relevant and better replicate tumor complexities. Compared to murine models, 3D models are cheaper, faster, and can study the human immune system. In this review, we discuss the most common 3D culture systems—spheroids, organoids, and microfluidic chips—and detail how these systems have advanced our understanding of cancer immunology.


2021 ◽  
Vol 22 (5) ◽  
pp. 2645
Author(s):  
Dinh Nam Tran ◽  
Seon Myeong Go ◽  
Seon-Mi Park ◽  
Eui-Man Jung ◽  
Eui-Bae Jeung

Inflammatory bowel diseases (IBDs) comprises a range of chronic inflammatory conditions of the intestinal tract. The incidence and prevalence of IBDs are increasing worldwide, but the precise etiology of these diseases is not completely understood. Calcium signaling plays a regulatory role in cellular proliferation. Nckx3, a potassium-dependent Na+/Ca2+ exchanger, is not only expressed in the brain but also in the aortic, uterine, and intestinal tissues, which contain abundant smooth muscle cells. This study investigated the role of Nckx3 in intestinal inflammation. Microarray analyses revealed the upregulation of the innate immune response-associated genes in the duodenum of Nckx3 knockout (KO) mice. The Nckx3 KO mice also showed an increase in IBD- and tumorigenesis-related genes. Using dextran sodium sulfate (DSS)-induced experimental colitis mice models, the Nckx3 KO mice showed severe colitis. Furthermore, the pathways involving p53 and NF-κB signaling were significantly upregulated by the absence of Nckx3. Overall, Nckx3 plays a critical role in the innate immune and immune response and may be central to the pathogenesis of IBD.


2016 ◽  
Vol 311 (6) ◽  
pp. R1135-R1148 ◽  
Author(s):  
Joshua W. Smith ◽  
Nikki A. Ford ◽  
Jennifer M. Thomas-Ahner ◽  
Nancy E. Moran ◽  
Eric C. Bolton ◽  
...  

β-Carotene-15,15’-dioxygenase (BCO1) cleaves dietary carotenoids at the central 15,15’ double bond, most notably acting on β-carotene to yield retinal. However, Bco1 disruption also impacts diverse physiological end points independent of dietary carotenoid feeding, including expression of genes controlling androgen metabolism. Using the Bco1−/− mouse model, we sought to probe the effects of Bco1 disruption on testicular steroidogenesis, prostatic androgen signaling, and prostatic proliferation. Male wild-type (WT) and Bco1−/− mice were raised on carotenoid-free AIN-93G diets before euthanasia between 10 and 14 wk of age. Weights of the prostate and seminal vesicles were significantly lower in Bco1−/− than in WT mice (−18% and −29%, respectively). Serum testosterone levels in Bco1−/− mice were significantly reduced by 73%. Bco1 disruption significantly reduced Leydig cell number and decreased testicular mRNA expression of Hsd17b3, suggesting inhibition of testicular testosterone synthesis. Immunofluorescent staining of the androgen receptor (AR) in the dorsolateral prostate lobes of Bco1−/− mice revealed a decrease in AR nuclear localization. Analysis of prostatic morphology suggested decreases in gland size and secretion. These findings were supported by reduced expression of the proliferation marker Ki-67 in Bco1−/− prostates. Expression analysis of 200 prostate cancer- and androgen-related genes suggested that Bco1 loss significantly disrupted prostatic androgen receptor signaling, cell cycle progression, and proliferation. This is the first demonstration that Bco1 disruption lowers murine circulating testosterone levels and thereby reduces prostatic androgen receptor signaling and prostatic cellular proliferation, further supporting the role of this protein in processes more diverse than carotenoid cleavage.


2021 ◽  
Vol 12 (9) ◽  
Author(s):  
Fan Zhao ◽  
Tao Zheng ◽  
Wenbin Gong ◽  
Jie Wu ◽  
Haohao Xie ◽  
...  

AbstractCrohn’s disease (CD) is an intestinal immune-dysfunctional disease. Extracellular vesicles (EVs) are membrane-enclosed particles full of functional molecules, e.g., nuclear acids. Recently, EVs have been shown to participate in the development of CD by realizing intercellular communication among intestinal cells. However, the role of EVs carrying double-strand DNA (dsDNA) shed from sites of intestinal inflammation in CD has not been investigated. Here we isolated EVs from the plasma or colon lavage of murine colitis and CD patients. The level of exosomal dsDNA, including mtDNA and nDNA, significantly increased in murine colitis and active human CD, and was positively correlated with the disease activity. Moreover, the activation of the STING pathway was verified in CD. EVs from the plasma of active human CD triggered STING activation in macrophages in vitro. EVs from LPS-damaged colon epithelial cells were also shown to raise inflammation in macrophages via activating the STING pathway, but the effect disappeared after the removal of exosomal dsDNA. These findings were further confirmed in STING-deficient mice and macrophages. STING deficiency significantly ameliorated colitis. Besides, potential therapeutic effects of GW4869, an inhibitor of EVs release were assessed. The application of GW4869 successfully ameliorated murine colitis by inhibiting STING activation. In conclusion, exosomal dsDNA was found to promote intestinal inflammation via activating the STING pathway in macrophages and act as a potential mechanistic biomarker and therapeutic target of CD.


2021 ◽  
Vol 28 (10) ◽  
pp. 683-693
Author(s):  
Vivian Rosery ◽  
Henning Reis ◽  
Konstantinos Savvatakis ◽  
Bernd Kowall ◽  
Martin Stuschke ◽  
...  

The tumor immune microenvironment (TME) represents a key determinant for responses to cancer treatment. However, the immune phenotype of highly proliferative gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) is still largely elusive. In this retrospective study, we characterized the TME of high-grade (G3, Ki-67 > 20%) GEP-NEN. We analyzed formalin-fixed paraffin-embedded samples from 37 patients with GEP-NEN G3 by immunohistochemistry and multiplex immunofluorescence to address the abundance and spatial interaction of relevant immune subsets. We focused on the expression of immune checkpoint molecules PD-1 and PD-L1, the cytotoxic T-cell marker CD8, and the tumor-associated macrophage marker CD206. Findings were correlated with overall survival (OS) from the date of a cancer diagnosis. Patients with PD-L1-positive tumors (CPS ≥ 1) and intense PD-1+CD8+ immune cell infiltration showed the most favorable median OS. Multiplex immunofluorescence staining of ten representative tissue samples illustrated intratumoral heterogeneity of PD-L1 expression. Dense PD-1+CD8+ immune cell infiltrates were observed in PD-L1-positive tumor regions but not in PD-L1-negative regions. Proximity analysis revealed a spatial interaction between PD-1+CD8+ cells and PD-L1-positive cells. Our data suggest a pre-existing antitumor immune response in the TME in a subgroup of GEP-NEN G3. This supports a targeted clinical exploration of immunotherapeutic approaches.


Author(s):  
Kent Tadokoro ◽  
Colten Wolf ◽  
Joseph Toth ◽  
Cara Joyce ◽  
Meharvan Singh ◽  
...  

Abstract Objectives Ki-67/MIB-1 is a marker of cellular proliferation used as a pathological parameter in the clinical assessment of pituitary adenomas, where its expression has shown utility in predicting the invasiveness of these tumors. However, studies have shown variable results when using Ki-67/MIB-1 association with recurrence. The purpose of this study is to determine if a high Ki-67/MIB-1 labeling index (LI) is predictive of recurrence in pituitary adenomas. Methods A retrospective chart review was performed for patients undergoing pituitary adenoma resection with at least 1 year of follow-up. Additionally, systematic data searches were performed and included studies that correlated recurrence rate to Ki-67/MIB-1 LI. Our institutional data were included in a synthesis with previously published data. Results Our institutional review included 79 patients with a recurrence rate of 26.6%. We found that 8.8% of our patients had a high Ki-67/MIB-1 LI (>3%); however, high Ki-67/MIB-1 was not associated with recurrence. The systematic review identified 244 articles and 49 full-text articles that were assessed for eligibility. Quantitative analysis was performed on 30 articles including our institutional data and 18 studies reported recurrence by level of Ki-67/MIB-1 LI. Among studies that compared Ki-67/MIB-1 ≥3 vs. <3%, 10 studies reported odds ratios (OR) greater than 1 of which 6 were statistically significant. A high Ki-67/MIB-1 had higher odds of recurrence via the pooled odds ratio (OR = 4.15, 95% confidence interval [CI]: 2.31–7.42). Conclusion This systematic review suggests that a high Ki-67/MIB-1 should prompt an increased duration of follow-up due to the higher odds of recurrence of pituitary adenoma.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Christopher T Cottage ◽  
Savilla Tuck ◽  
Kimberlee Fischer ◽  
Natalie Gude ◽  
John Muraski ◽  
...  

Cardiac progenitor cells (CPCs) blunt cardiomyopathic damage and increase survival following adoptive transfer into hearts subjected to myocardial infarction (MI), but the initial survival, persistence, and long term engraftment of the donated cell population remains problematic. Previous studies from our group have demonstrated that transgenes driven by the α -myosin heavy chain gene promoter are expressed in the CPC population allowing for enhanced proliferation and survival. This study details a genetic engineering strategy to augment the salutary effects of CPCs through the use of a serine/threonine kinase named Pim-1 that promotes cellular proliferation and survival. Transgenic mice created with cardiac-specific Pim-1 overexpression (Pim-wt) exhibit enhanced Pim-1 activity in both cardiomyocytes and CPCs, both of which show increased proliferative activity assessed using BrdU or Ki-67 markers relative to non-transgenic (NTG) controls. However, CPC population number was not increased in the Pim-wt hearts during normal postnatal growth or after infarction challenge, suggesting that Pim-1 expression promotes asymmetric division resulting in maintenance of the CPC pool as well as expansion of the cardiomyocyte population. Localization and quantitation of cell fate determinants Numb and α -adaptin by confocal microscopy were employed to assess levels of asymmetric division in the CPC population. Polarization of Numb in mitotic phospho-histone positive cells demonstrates asymmetric division in 65% of the CPC population in hearts of Pim-wt mice versus 26% in NTG hearts after infarction challenge. Similarly, Pim-wt hearts had fewer cells with uniform α -adaptin staining indicative of symmetrically dividing CPCs, with in 36% of the CPCs versus vs. 73% in NTG sections. These findings define a mechanistic basis for enhanced myocardial regeneration in transgenic mice overexpressing Pim-1 kinase in the myocardial lineage cells.


2015 ◽  
Vol 26 (4) ◽  
pp. 416-421 ◽  
Author(s):  
Fernanda Viviane Mariano ◽  
Ana Flávia Costa ◽  
Rogério Oliveira Gondak ◽  
Antonio Santos Martins ◽  
André Del Negro ◽  
...  

<p>Carcinoma ex pleomorphic adenoma (CXPA) has been considered an interesting model of carcinogenesis, presenting various histological subtypes and invasiveness phase. The objective was to determine the proliferative index of CXPA and comparing to pleomorphic adenoma (PA). Thirty six cases of CXPA (36 PA) and 22 areas of PA in CXPA (residual PA) were studied by Ki-67 expression. All CXPA cases were classified according to invasiveness phase (intracapsular, minimally and frankly invasive) and histopathological subtypes. Data was statistically analyzed by Wilcoxon, Mann-Whitney and Kruskal-Wallis tests. CXPA included 5 intracapsular, 9 minimally invasive and 22 frankly invasive cases. Fifteen cases corresponded to salivary duct carcinoma, 7 to adenocarcinoma NOS, 7 myoepithelial, 5 epithelial-myoepithelial, one case of squamous cell and one case of sarcomatoid carcinoma. The Ki-67 index of PA and residual PA were significantly lower than CXPA. Intracapsular and minimally invasive showed smaller proliferative index than frankly invasive. Considering the subtypes of CXPA, there was not a statistic difference among them. Ki-67 is a useful marker in the differential diagnosis of PA and CXPA, even when in the early invasive phase.</p>


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