scholarly journals Roles of 5-Lipoxygenase and Cysteinyl-Leukotriene Type 1 Receptors in the Hematological Response to Allergen Challenge and Its Prevention by Diethylcarbamazine in a Murine Model of Asthma

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Daniela Masid-de-Brito ◽  
Túlio Queto ◽  
Maria Ignez C. Gaspar-Elsas ◽  
Pedro Xavier-Elsas

Diethylcarbamazine (DEC), which blocks leukotriene production, abolishes the challenge-induced increase in eosinopoiesis in bone-marrow from ovalbumin- (OVA-) sensitized mice, suggesting that 5-lipoxygenase (5-LO) products contribute to the hematological responses in experimental asthma models. We explored the relationship between 5-LO, central and peripheral eosinophilia, and effectiveness of DEC, using PAS or BALB/c mice and 5-LO-deficient mutants. We quantified eosinophil numbers in freshly harvested or cultured bone-marrow, peritoneal lavage fluid, and spleen, with or without administration of leukotriene generation inhibitors (DEC and MK886) and cisteinyl-leukotriene type I receptor antagonist (montelukast). The increase in eosinophil numbers in bone-marrow, observed in sensitized/challenged wild-type mice, was abolished by MK886 and DEC pretreatment. In ALOX mutants, by contrast, there was no increase in bone-marrow eosinophil counts, nor in eosinophil production in culture, in response to sensitization/challenge. In sensitized/challenged ALOX mice, challenge-induced migration of eosinophils to the peritoneal cavity was significantly reduced relative to the wild-type PAS controls. DEC was ineffective in ALOX mice, as expected from a mechanism of action dependent on 5-LO. In BALB/c mice, challenge significantly increased spleen eosinophil numbers and DEC treatment prevented this increase. Overall, 5-LO appears as indispensable to the systemic hematological response to allergen challenge, as well as to the effectiveness of DEC.

Endocrinology ◽  
2008 ◽  
Vol 149 (8) ◽  
pp. 4080-4085 ◽  
Author(s):  
Maria Pini ◽  
Melissa E. Gove ◽  
Joseph A. Sennello ◽  
Jantine W. P. M. van Baal ◽  
Lawrence Chan ◽  
...  

Adipokines, cytokines mainly produced by adipocytes, are active participants in the regulation of inflammation. Administration of zymosan (ZY) was used to investigate the regulation and role of adipokines during peritonitis in mice. Injection of ZY led to a significant increase in leptin levels in both serum and peritoneal lavage fluid, whereas a differential trend in local vs. systemic levels was observed for both resistin and adiponectin. The role of leptin in ZY-induced peritonitis was investigated using leptin-deficient ob/ob mice, with and without reconstitution with exogenous leptin. Leptin deficiency was associated with delayed resolution of peritoneal inflammation induced by ZY, because ob/ob mice had a more pronounced cellular infiltrate in the peritoneum as well as higher and prolonged local and systemic levels of IL-6, TNFα, IL-10, and chemokine (C-X-C motif) ligand 2 compared with wild-type mice. Reconstitution with exogenous leptin exacerbated the inflammatory infiltrate and systemic IL-6 levels in ob/ob mice while inhibiting production of TNFα, IL-10, and chemokine (C-X-C motif) ligand 2. In contrast with the important role of leptin in regulating each aspect of ZY-induced peritonitis, adiponectin deficiency was associated only with a decreased inflammatory infiltrate, without affecting cytokine levels. These findings point to a complex role for adipokines in ZY-induced peritonitis and further emphasize the interplay between obesity and inflammation.


Vaccines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 743
Author(s):  
Ricardo Wesley Alberca ◽  
Eliane Gomes ◽  
Momtchilo Russo

Allergen-specific T helper (Th)2 cells orchestrate upon allergen challenge the development of allergic eosinophilic lung inflammation. Sensitization with alum adjuvant, a type 2 adjuvant, has been used extensively in animal models of allergic lung disease. In contrast, type 1 adjuvants like CpG-ODN, a synthetic toll-like receptor 9 agonist, inhibit the development of Th2 immunity. CpG-ODN induce type 1 and suppressive cytokines that influence Th2 cell differentiation. Here, we investigated the immune modulatory effect of CpG-ODN on allergic sensitization to OVA with alum focusing on dendritic cells (DCs) expressing the MyD88 molecule and the suppressive IL-10 cytokine. Using mice with specific cell deletion of MyD88 molecule, we showed that CpG-ODN suppressed allergic sensitization and consequent lung allergic inflammation signaling through the MyD88 pathway on dendritic cells, but not on B-cells. This inhibition was associated with an increased production of IL-10 in the bronchoalveolar lavage fluid. Sensitization to OVA with CpG-ODN of IL-10-deficient, but not wild-type mice, induced a shift towards Th1 pattern of inflammation. Employing bone marrow-derived dendritic cells (BM-DCs) pulsed with OVA for sensitizations with or without CpG-ODN, we showed that IL-10 is dispensable for the inhibition of allergic lung Th2 responses by CpG-ODN. Moreover, the lack of IL-10 on DCs was not sufficient for the CpG-ODN-induced immune-deviation towards a Th1 pattern. Accordingly, we confirmed directly the role of MyD88 pathway on DCs in the inhibition of allergic sensitization.


2011 ◽  
Vol 300 (5) ◽  
pp. R1250-R1260 ◽  
Author(s):  
Katherine J. Motyl ◽  
Michelle Raetz ◽  
Srinivasan Arjun Tekalur ◽  
Richard C. Schwartz ◽  
Laura R. McCabe

Bone loss in type 1 diabetes is accompanied by increased marrow fat, which could directly reduce osteoblast activity or result from altered bone marrow mesenchymal cell lineage selection (adipocyte vs. osteoblast). CCAAT/enhancer binding protein beta (C/EBPβ) is an important regulator of both adipocyte and osteoblast differentiation. C/EBPβ-null mice have delayed bone formation and defective lipid accumulation in brown adipose tissue. To examine the balance of C/EBPβ functions in the diabetic context, we induced type 1 diabetes in C/EBPβ-null (knockout, KO) mice. We found that C/EBPβ deficiency actually enhanced the diabetic bone phenotype. While KO mice had reduced peripheral fat mass compared with wild-type mice, they had 5-fold more marrow adipocytes than diabetic wild-type mice. The enhanced marrow adiposity may be attributed to compensation by C/EBPδ, peroxisome proliferator-activated receptor-γ2, and C/EBPα. Concurrently, we observed reduced bone density. Relative to genotype controls, trabecular bone volume fraction loss was escalated in diabetic KO mice (−48%) compared with changes in diabetic wild-type mice (−22%). Despite greater bone loss, osteoblast markers were not further suppressed in diabetic KO mice. Instead, osteoclast markers were increased in the KO diabetic mice. Thus, C/EBPβ deficiency increases diabetes-induced bone marrow (not peripheral) adipose depot mass, and promotes additional bone loss through stimulating bone resorption. C/EBPβ-deficiency also reduced bone stiffness and diabetes exacerbated this (two-way ANOVA P < 0.02). We conclude that C/EBPβ alone is not responsible for the bone vs. fat phenotype switch observed in T1 diabetes and that suppression of CEBPβ levels may further bone loss and decrease bone stiffness by increasing bone resorption.


2017 ◽  
Vol 5 (6) ◽  
pp. 771-773 ◽  
Author(s):  
Ahmet Öğrenci ◽  
Orkun Koban ◽  
Murat Ekşi ◽  
Onur Yaman ◽  
Sedat Dalbayrak

Downward displacement of cerebellar tonsils more than 5 mm below the foramen magnum is named as Chiari type I malformation and named benign tonsillar ectopia if herniation is less than 3 mm. It does not just depend on congenital causes. There are also some reasons for acquired Chiari Type 1 and benign tonsillar ectopia/herniation. Trauma is one of them. Trauma may increase tonsillar ectopia or may be the cause of new-onset Chiari type 1. The relationship between the tonsil contusion and its position is unclear. We present a case of pediatric age group with tonsillar herniation with a hemorrhagic contusion. Only 1 case has been presented so far in the literature. A case with unilateral tonsil contusion has not been presented to date. We will discuss the possible reasons for taking the place of the tonsils to the above level of the foramen magnum in the follow-up period, by looking at the literature.


Blood ◽  
2000 ◽  
Vol 96 (6) ◽  
pp. 2172-2180 ◽  
Author(s):  
Kotaro Suzuki ◽  
Hiroshi Nakajima ◽  
Norihiko Watanabe ◽  
Shin-ichiro Kagami ◽  
Akira Suto ◽  
...  

Abstract The regulatory roles of the common cytokine receptor γ chain (γc)– and Jak3-dependent signaling in the proliferation and survival of mast cells were determined using γc-deficient (γc−) and Jak3-deficient (Jak3−) mice. Although the mast cells in γc− and Jak3− mice were morphologically indistinguishable from those in wild-type mice, the number of peritoneal mast cells was decreased in γc− and Jak3− mice as compared with that in wild-type mice. Among γc-related cytokines, interleukin (IL)-4 and IL-9, but not IL-2, IL-7, or IL-15, enhanced the proliferation and survival of bone marrow–derived mast cells (BMMCs) from wild-type mice. However, the effects of IL-4 and IL-9 were absent in BMMCs from γc− and Jak3−mice. In addition, IL-4Rα, γc, and Jak3, but not IL-2Rβ or IL-7Rα, were expressed in BMMCs. In contrast, IL-13 did not significantly induce the proliferation and survival of BMMCs even from wild-type mice, and IL-13Rα1 was not expressed in BMMCs. Furthermore, IL-4 phosphorylated the 65-kd isoform of Stat6 in BMMCs from wild-type mice but not from γc− and Jak3− mice. These results indicate that γc- and Jak3-dependent signaling is essential for IL-4– and IL-9–induced proliferation and survival of murine mast cells, that the effects of IL-4 are mediated by type I IL-4R and that type II IL-4R is absent on mast cells, and that IL-4 phosphorylates the 65-kd isoform of Stat6 in mast cells in a γc- and Jak3-dependent manner.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
P. Xavier-Elsas ◽  
C. L. C. A. Silva ◽  
L. Pinto ◽  
T. Queto ◽  
B. M. Vieira ◽  
...  

Allergic airway inflammation is attenuated by oral tolerization (oral exposure to allergen, followed by conventional sensitization and challenge with homologous antigen), which decreases airway allergen challenge-induced eosinophilic infiltration of the lungs and bone marrow eosinophilia. We examined its effects on bone marrow eosinophil and neutrophil production. Mice of wild type (BP-2, BALB/c, and C57BL/6) and mutant strains (lacking iNOS or CD95L) were given ovalbumin (OVA) or water (vehicle) orally and subsequently sensitized and challenged with OVA (OVA/OVA/OVA and H2O/OVA/OVA groups, resp.). Anti-OVA IgG and IgE, bone marrow eosinophil and neutrophil numbers, and eosinophil and neutrophil production ex vivo were evaluated. T lymphocytes from OVA/OVA/OVA or control H2O/OVA/OVA donors were transferred into naïve syngeneic recipients, which were subsequently sensitized/challenged with OVA. Alternatively, T lymphocytes were cocultured with bone marrow eosinophil precursors from histocompatible sensitized/challenged mice. OVA/OVA/OVA mice of the BP-2 and BALB/c strains showed, relative to H2O/OVA/OVA controls, significantly decreased bone marrow eosinophil counts and ex vivo eosinopoiesis/neutropoiesis. Full effectiveness in vivo required sequential oral/subcutaneous/intranasal exposures to the same allergen. Transfer of splenic T lymphocytes from OVA/OVA/OVA donors to naive recipients prevented bone marrow eosinophilia and eosinopoiesis in response to recipient sensitization/challenge and supressed eosinopoiesis upon coculture with syngeneic bone marrow precursors from sensitized/challenged donors.


1997 ◽  
Vol 186 (12) ◽  
pp. 1997-2004 ◽  
Author(s):  
Mitsuru Matsumoto ◽  
Yang-Xin Fu ◽  
Hector Molina ◽  
Guangming Huang ◽  
Jinho Kim ◽  
...  

In mice deficient in either lymphotoxin α (LT-α) or type I tumor necrosis factor receptor (TNFR-I), organized clusters of follicular dendritic cells (FDC) and germinal centers (GC) are absent from the spleen. We investigated the role of LT-α and TNFR-I in the establishment of spleen FDC and GC structure by using reciprocal bone marrow (BM) transfer. When LT-α–deficient mice were reconstituted with wild-type BM, FDC organization and the ability to form GC were restored, indicating that the LT-α–expressing cells required to establish organized FDC are derived from BM. The role of LT-α in establishing organized FDC structure was further investigated by the transfer of complement receptor 1 and 2 (CR1/2)–deficient BM cells into LT-α–deficient mice. Organized FDC were identified with both the FDC-M1 and anti-CR1 monoclonal antibodies in these BM-chimeric mice, indicating that these cells were derived from the LT-α–deficient recipient. Thus, expression of LT-α in the BM-derived cells, but not in the non–BM-derived cells, is required for the maturation of FDC from non-BM precursor cells. In contrast, when TNFR-I–deficient mice were reconstituted with wild-type BM, they showed no detectable FDC clusters or GC formation. This indicates that TNFR-I expression on non–BM-derived cellular components is necessary for the establishment of these lymphoid structures. TNFR-I–deficient BM was able to restore FDC organization and GC formation in LT-α–deficient mice, indicating that formation of these structures does not require TNFR-I expression on BM-derived cells. The data in this study demonstrate that FDC organization and GC formation are controlled by both LT-α–expressing BM-derived cells and by TNFR-I-expressing non–BM-derived cells.


2010 ◽  
Vol 87 (5) ◽  
pp. 885-893 ◽  
Author(s):  
Tulio Queto ◽  
Maria I. Gaspar-Elsas ◽  
Daniela Masid-de-Brito ◽  
Zilton F. M. Vasconcelos ◽  
Fausto K. Ferraris ◽  
...  

2021 ◽  
Author(s):  
Katarina Bojkovic ◽  
Jennifer Rodgers ◽  
Riddhi Vichare ◽  
Asmita Nandi ◽  
Hussein Mansour ◽  
...  

Abstract Oxygen supplementation, although a cornerstone of emergency and cardiovascular medicine, often results in hyperoxia, a condition characterized by excessive tissue oxygen which results in adverse cardiac remodeling and subsequent injurious effects to physiological function. Cardiac remodeling is further influenced by various risk factors, including pre-existing conditions and sex. Thus, the purpose of this experiment was to investigate cardiac remodeling in Type I Diabetic (Akita) mice subjected to hyperoxic treatment. Overall, we demonstrated that Akita mice experience distinct challenges from wild type (WT) mice. Specifically, Akita males at both normoxia and hyperoxia showed significant decreases in body and heart weights, prolonged PR, QRS, and QTc intervals, and reduced %EF and %FS at normoxia compared to WT controls. Moreover, Akita males largely resemble female mice (both WT and Akita) with regards to the parameters studied. Finally, statistical analysis revealed hyperoxia to have the greatest influence on cardiac pathophysiology, followed by sex, and finally genotype. Taken together, our data suggest that Type I diabetic patients may have distinct cardiac pathophysiology under hyperoxia compared to uncomplicated patients, with males being at high risk. These findings can be used to enhance provision of care in ICU patients with Type I diabetes as a comorbid condition.


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