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BACKGROUND: Asthma is a complex and chronic inflammatory airway disease. Asthma's etiology is unknown; however, genetic and environmental factors could affect disease susceptibility. We designed a case-control study aimed to evaluate the role of single-nucleotide polymorphisms (SNP), and copy-number variants (CNV) in the IL4 and IL13 genes in asthma susceptibility and their participation in plasma cytokine levels depending on genotypes Methods: We include 486 subjects, divided into asthma patients (AP, n = 141) and clinically healthy subjects (CHS, n = 345). We genotyped three SNP, two in the IL4 and two in the IL13 gene; also, two CNVs in IL4. The IL-4, IL-13 and IgE plasma levels were quantified. RESULTS: Biomass-burning smoke exposure was higher in the AP group compared to CHS (47.5% vs. 20.9%; p < 0.01, OR = 3.4). No statistical differences were found in the genetic association analysis. In both CNV, we only found the common allele. For the analysis of IL-4, IL-13, and IgE measures stratified by genotypes, no significant association or correlation was found. CONCLUSION: In the Mexican-mestizo population, SNPs neither CNVs in IL4 nor IL13 are associated with asthma susceptibility or involved serum cytokine levels. Biomass-burning smoke is a risk factor in asthma susceptibility.
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Purpose: The protease inhibitor S (PiS) and Z (PiZ) variants have been stated as the only genetic cause of chronic obstructive pulmonary disease (COPD) in Caucasians. However, its frequency in admixed populations is low. We aimed to identify genetic susceptibility between PiS (rs17580) and PiZ (rs28929474) polymorphisms with COPD related to tobacco smoking and biomass-burning smoke as well as to determine its frequencies in Mestizo and Amerindian populations from Mexico. Patients and Methods: One thousand and eight hundred seventy-eight subjects were included in two comparisons of cases and controls, (1) smokers with and without COPD (COPD-S, n=399; SWOC, n=1106); (2) Biomass-burning smoke-exposed subjects with and without COPD (COPD-BS, n=98; BBES, n=275). In addition, 2354 Mexican subjects identified as Mestizos (n=1952) and Amerindian (n=402) were included. The population structure was evaluated using 59 informative ancestry markers. Results: The AT genotype of rs17580 is associated with COPD in both comparisons (COPD-S vs SWOC p<0.001, OR=2.16; COPD-BS vs BBES p<0.0001, OR=11.50). The population of the Mexico-North has a greater Caucasian contribution (54.7%) compared to the center (46.9%) and southeast (42.7%). Conclusion: The rs17580, AT genotype, is associated with COPD in Mexican-Mestizo smokers and exposed to biomass-burning smoke. The rs17580 AT is more frequent in the Mexican-Mestizo population of the North of the country, which has a high Caucasian component.
Assuntos
Doença Pulmonar Obstrutiva Crônica , alfa 1-Antitripsina , Biomassa , Estudos de Casos e Controles , Genótipo , Humanos , México/epidemiologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Fumar Tabaco , alfa 1-Antitripsina/genéticaRESUMO
There is an increase in the prevalence of asthma and obesity, constituting a public health problem at national and global levels. The association between the two pathologies has not been clearly determined; however, a certain synergy has been proposed, which leads to more severe bronchospasms, longer recovery time, and more prolonged use of medications in obese asthmatic patients. The discovery of leptin, an adipokine that is directly related to the amount of total body fat and the production of proinflammatory cytokines, has generated greater interest in white adipose tissue. Our objective was to describe the possible mechanisms involved and the association between obesity and asthma. A bibliographic search was conducted in the scientific literature using the National Biotechnology Information Center (NCBI) database of the USA as a search tool; keywords used were: asthma, leptin, obesity and inflammation. There are numerous clinical and experimental studies that explore the role of obesity as an inflammatory entity in asthma, some of which have evaluated the role of "shared" genetic polymorphisms in both pathologies. Apparently, the interaction between asthma and obesity is complex, there are mechanisms that link both pathologies, these can influence the improvement or exacerbation of symptoms.
El incremento en la prevalencia de asma y obesidad constituye un problema de salud pública en los ámbitos nacional y mundial. Se ha propuesto una sinergia entre estas patologías que genera broncoespasmos más severos, mayor tiempo de recuperación y uso de medicamentos por un lapso más prolongado en los pacientes asmáticos con obesidad. El descubrimiento de la leptina, relacionada directamente con la cantidad de grasa corporal total y la producción de citocinas proinflamatorias ha generado mayor interés en el tejido adiposo blanco. El objetivo de esta investigación fue describir la asociación entre obesidad, asma y los mecanismos fisiopatológicos involucrados. Se realizó una búsqueda bibliográfica en la literatura científica empleando el Centro Nacional de Información sobre Biotecnología (NCBI) de Estados Unidos como herramienta de búsqueda; las palabras claves utilizadas fueron asma, leptina, obesidad e inflamación. Numerosos estudios clínicos y experimentales exploran la participación de la obesidad como una entidad inflamatoria en el asma; algunos han evaluado el papel de polimorfismos genéticos "compartidos" por ambas patologías. Al parecer, existen mecanismos comunes a ambas patologías que pueden influir en la exacerbación de los síntomas del asma en pacientes con obesidad.
Assuntos
Asma/imunologia , Mediadores da Inflamação/fisiologia , Inflamação/imunologia , Obesidade/imunologia , Tecido Adiposo/fisiopatologia , Asma/epidemiologia , Asma/genética , Asma/fisiopatologia , Espasmo Brônquico/etiologia , Espasmo Brônquico/fisiopatologia , Comorbidade , Citocinas/fisiologia , Dieta , Predisposição Genética para Doença , Humanos , Inflamação/epidemiologia , Leptina/sangue , Obesidade/epidemiologia , Obesidade/genética , Mecânica RespiratóriaRESUMO
Aspirin exacerbated respiratory disease (AERD) is characterized by chronic hyperplastic rhinosinusitis, nasal polyposis, asthma, and aspirin sensitivity. The mechanisms which produce these manifestations of intolerance are not fully defined, current research focuses on cyclooxygenase 1 (COX-1) inhibition, metabolism of arachidonic acid, and the COX pathway to the lipoxygenase (LO) route, inducing increased synthesis of leukotrienes (LT). The biological plausibility of this model has led to the search for polymorphisms in genes responsible for proinflammatory cytokines synthesis, such as IL1B and IL8. We performed a genetic association study between IL8-251 (rs4073) and IL1B-511 (rs16944) polymorphisms in AERD, aspirin-tolerant asthma (ATA), and healthy control subjects. Using allelic discrimination by real-time PCR, we found statistically nonsignificant associations between AERD, ATA, and healthy control subjects for the GG and GA genotypes of IL1B (rs16944). Interestingly, the AA genotype showed an increased frequency in the AERD patients versus the ATA group (GF = 0.19 versus 0.07, p = 0.018, OR 2.98, and 95% CI 1.17-7.82). This is the first observation that IL1B polymorphisms are involved in AERD. Thus, future studies must investigate whether interleukin-1ß is released in the airways of AERD patients and whether it relates to genetic polymorphisms in the IL1B gene.