The effects of an insertion in the 5 ' UTR of the AMCase on gene expression and pulmonary functions

Cataloged from PDF version of article.Background: Studies regarding the physiological role of acidic mammalian chitinase (AMCase) and the effects of its genetic variants on asthma have produced conflicting results. Objectives: We aimed to determine the genetic variants in the AMCase gene that could regulate the gene expression and thus influence disease severity. Methods: Genetic variants of the AMCase gene were determined by sequencing of asthmatics and healthy controls in up to -1 kb in the promoter region and exon 1 and 2. In an association study, a population of asthmatic (n = 504) and healthy Turkish children (n = 188) were genotyped for the observed SNPs. A replication study was performed in a North American adult population of patients with mild (n = 317) and severe (n = 145) asthma. The functional properties of the insertion were determined by promoter reporter assay, electromobility shift assay and transcription factor ELISA experiments. Results: Of the identified SNPs, only a ten base pair insertion (CAATCTAGGC) in the 5'UTR region of exon 2 was significantly associated with lower FEV(1) (beta = -14.63 SE = 6.241, P = 0.019) in Turkish children with asthma. However, in the adult population, the same insertion showed a trend toward higher FEV(1). The insertion was shown to have enhancer activity and the mutant probe possessing the insertion had higher binding affinity for the nuclear extracts. Conclusion: Our study shows that a ten base pair insertion in the 5'UTR region of AMCase gene may modify gene expression and thus may affect the severity of asthma. However, its effects appear to be different in different populations. (C) 2011 Elsevier Ltd. All rights reserved

Antiangiogenic response after 70% hepatectomy and its relationship with hepatic regeneration and angiogenesis in rats

Background: The aim of this study was to evaluate the antiangiogenic response and its relation to regeneration and angiogenesis after 70% hepatectomy in a rat model. Methods: Sixty-four Wistar albino rats were included in the study. Animals were allocated into 8 groups (n = 8). After a 70% hepatectomy, liver regeneration, angiogenesis, and antiangiogenic response were evaluated in the remnant liver on days 0, 1, 2, 3, 5, 7, 10, and 14. Regeneration and angiogenesis were determined with immunoreactivity to proliferating cell nuclear antigen and vascular endothelial growth factor. Antiangiogenic response was evaluated by detecting collagen 18 m RNA with reverse transcriptase polymerase chain reaction. Results: We showed that liver regeneration peaked at day 1, whereas angiogenesis in the periportal and perisinusoidal areas reached their peak values on days 3 and 7, respectively. Both regeneration and angiogenic activity around perisinusoidal hepatocytes returned to basal activity on the day 10. Antiangiogenic response first appeared on day 5, reached a peak on day 10, and returned to basal values on day 14. Conclusion: Collagen18 mRNA expression is present in the normal liver during the regenerative process. We suggest that the stimulus that causes the cessation of regeneration process may come from hepatocytes, and collagen 18 produced by hepatocytes may modulate this event by inhibiting the angiogenesis. © 2010 Mosby, Inc. All rights reserved

Triclosan Disrupts SKN-1/Nrf2- Mediated Oxidative Stress Response in C. elegans and Human Mesenchymal Stem Cells

Triclosan (TCS), an antimicrobial chemical with potential endocrine-disrupting properties, may pose a risk to early embryonic development and cellular homeostasis during adulthood. Here, we show that TCS induces toxicity in both the nematode C. elegans and human mesenchymal stem cells (hMSCs) by disrupting the SKN-1/Nrf2-mediated oxidative stress response. Specifically, TCS exposure affected C. elegans survival and hMSC proliferation in a dose-dependent manner. Cellular analysis showed that TCS inhibited the nuclear localization of SKN-1/Nrf2 and the expression of its target genes, which were associated with oxidative stress response. Notably, TCS-induced toxicity was significantly reduced by either antioxidant treatment or constitutive SKN-1/Nrf2 activation. As Nrf2 is strongly associated with aging and chemoresistance, these findings will provide a novel approach to the identification of therapeutic targets and disease treatment

Association Between Tuberculosis and Atopy: Role of the CD14-159C/T Polymorphism

WOS: 000305365200007PubMed: 22697010Background: The development of allergic hypersensitivity depends on both genetic and environmental factors. Different amounts of microbial products could affect patients with atopy and different genotypes. Objective: We aimed to evaluate the role of varying degrees of exposure to infection by Mycobacterium tuberculosis (tuberculosis) in atopic patients and analyze the association with genetic factors. Methods: We performed CD14-159C/T genotyping in atopic patients (n=118) and healthy individuals (n=62) and recorded the following variables: rural lifestyle, exposure to persons with tuberculosis, bacille Calmette-Guerin (BCG) vaccination, tuberculin skin test (TST), skin prick test, and phenotypes of atopy. Blood samples were analyzed for soluble-CD14 (sCD14), interferon (IFN) gamma, total immunoglobulin (Ig) E, and eosinophil levels. A score was used to identify the likelihood of exposure to tuberculosis. Results: Almost all the study participants had had a BCG vaccination, and half had a positive TST result. No differences were observed between atopic patients with high/low tuberculosis scores and CD14 genotypes in terms of atopic phenotypes, allergen sensitization, and levels of total IgE, sCD14, and IFN-gamma. However, the frequency of asthma was higher in atopic patients with a high tuberculosis score and was not associated with CD14 genotypes. Eosinophil counts in blood were higher in atopic patients with a high tuberculosis score and CC+CT genotypes. Conclusions: These results suggest that the C allele of the CD14-159C/T polymorphism has a marked effect on eosinophil levels in atopic patients with increased exposure to tuberculosis. In addition, the degree of exposure to tuberculosis in atopic patients may modify the development of asthma.Kirikkale UniversityKirikkale University [2008/5]This work was supported by a grant from Kirikkale University Projects of Scientific Research (Grant No. 2008/5) awarded to Drs Baccioglu Kavut, Kalpaklioglu, and Ayaslioglu. None of the authors have any other financial disclosures to make

Is CD14-159C/T gene polymorphism in atopy associated with tuberculosis or with hygiene hypothesis ?

29th Congress of the European-Academy-of-Allergy-and-Clinical-Immunology (EAACI) -- JUN 05-09, 2010 -- London, ENGLANDWOS: 000329462100450…European Acad Allergy and Clin Immuno

The effect of CD14 C159T polymorphism on in vitro IgE synthesis and cytokine production by PBMC from children with asthma

BACKGROUND: Even though the genotype at the promoter region of the CD14 molecule is known to affect the atopic phenotypes, the cellular and molecular basis of this association is largely unknown. OBJECTIVE: To investigate the effect of lipopolysaccharide (LPS) on IgE production and cytokine profile by peripheral blood mononuclear cells (PBMC) obtained from asthmatic children with the TT and the CC genotypes at position -159 of the CD14 gene. METHODS: Peripheral blood mononuclear cells from asthmatic children with alternative genotypes at CD14 C159T locus were stimulated with 2 and 200 ng/ml LPS in vitro. The IgE, IgG and, IgM response was determined by ELISA and Ig έ-germline, IgG, and IgM transcription by real-time PCR. A cluster of cytokines was measured by cytometric bead array. RESULTS: Asthmatic children with the TT genotype but not those with the CC genotype responded with increased IgE synthesis and germline transcription to LPS stimulation. There were no genotype-related differences in IgG and IgM. TT but not the CC genotype was associated with significantly increased interleukin (IL)-4/IL-12 and IL-4/interferon-gamma (IFN-γ) ratios in the culture supernatant. There were no genotype-related differences in IL-1β, IL-7, IL-10, IL-13, IL-17A, granulocyte colony stimulating factor, granulocyte macrophage colony stimulating factor, monocyte chemotactic protein, and tumor necrosis factor alpha. CONCLUSION: Peripheral blood mononuclear cells from asthmatic children with the TT genotype at position -159 of the CD14 gene make more IgE than those with the CC genotype following LPS stimulation because of increased germline transcription and have an augmented Th2 cytokine profile