RESUMO
Objective: To study the NAT2 gene polymorphisms 481T, 590A and 857A in the Chimila, Wiwa and Wayuu indigenous groups of the Colombian Caribbean to determine the frequencies of the alleles NAT2*4, NAT2*5, NAT2*6, and NAT2*7 and to determine the types of acetylators present in these populations. Methods: A total of 202 subjects were studied: 47 Chimila, 55 Wiwa, and 100 Wayuu. The polymorphisms were identified using a real-time PCR method for allelic discrimination designed using Taqman of Applied Biosystems. Results: The following alleles were found at the highest frequency in the following groups: the NAT2*4 allele (wild type) in the Wayuu group (55.3%), the NAT2*5 allele in the Wiwa group (34.5%), and the NAT2*7 allele in the Chimila group (24.2%). A higher frequency of the rapid acetylator status was found in the Wayuu group (31.3%) and Chimila group (29.5%) compared with the Wiwa group (12.7%). The intermediate acetylator status distribution was very similar in all three groups, and the frequency of the slow acetylator status was higher in the Wiwa group (32.7%) compared with the Chimila and Wayuu groups (20.5% and 21.2%, respectively). Conclusion: The results demonstrated the allelic distribution and pharmacogenetic differences of the three groups studied and revealed the most frequent acetylator status and phenotype. Because of the high prevalence of slow acetylators, a greater incidence of tuberculosis (TB) drug-induced hepatotoxicity is predicted in these populations, with a higher frequency in the Wiwa group.
Objetivo: Estudiar los polimorfismos tipo SNP (del inglés- single nucleotide polymorphism) 481T, 590A y 857A del gen NAT2, en los grupos indígenas Chimila, Wiwa y Wayúu del Caribe Colombiano para determinar las frecuencias de los alelos NAT2*4, NAT2*5, NAT2*6 y NAT2*7 y caracterizar el tipo de acetiladores presentes en estas poblaciones. Métodos: Se estudiaron 202 individuos en total, 47 Chimila, 55 Wiwa y 100 Wayúu. Los polimorfismos se determinaron mediante la técnica de PCR en tiempo real por el método de discriminación alélica Taqman de Applied Biosystems. Resultados: El alelo NAT2*4 (wild type) mostró una mayor frecuencia en el grupo Wayúu (55.3%), el alelo NAT2*5 en el grupo Wiwa (34.5%) y el alelo NAT2*7 en el grupo Chimila (24.2%). Se encontró una mayor frecuencia del estado acetilador rápido en el grupo Wayúu (31.3%) y en el grupo Chimila (29.5%) al compararse con el grupo Wiwa (12.7%). La distribución del estado acetilador intermedio es muy similar en los tres grupos, y para el estado acetilador lento observamos que en el grupo Wiwa la frecuencia es mayor (32.7%) con respecto a Chimila y Wayúu con 20.5% y 21.2% respectivamente. Conclusiones: Los resultados permitieron conocer la distribución alélica y el componente farmacogenético de los tres grupos estudiados; igualmente, deducir el estado acetilador y/o fenotipo más frecuente. Debido a la alta prevalencia de acetiladores lentos, se podría predecir un aumento de la incidencia de hepatotóxicidad inducida por medicamentos antituberculosos como la Isoniacida indicados en estas poblaciones y en mayor frecuencia en el grupo Wiwa.
Assuntos
Feminino , Humanos , Masculino , Arilamina N-Acetiltransferase/genética , Indígenas Sul-Americanos/genética , Farmacogenética , Polimorfismo de Nucleotídeo Único , Acetilação , Alelos , Colômbia , Reação em Cadeia da Polimerase em Tempo RealRESUMO
There is an increased susceptibility to infections during elderly, mainly because of the decreased efficacy of adaptive immunity to contain microorganisms. Albeit most of the elderly adults develop this deficiency in adaptive immunity only a minor percentage of them developed recurrent infectious diseases, thus innate immunity represents an important barrier to avoid infections in this group of aged people. Since antimicrobial peptides are important molecules of innate immunity in the study we sought to determine whether healthy aging correlates with a proper antimicrobial production. Our results by ELISA and flow cytometry showed that healthy elder individuals produce significant amounts of both cathelicidin and ß-defensin-2 (hBD-2) comparable with those found in healthy young individuals. Our results suggest that during healthy aging the maintenance of the antimicrobial peptide innate immune response may be responsible for the protection against infectious diseases.
Assuntos
Envelhecimento/imunologia , Peptídeos Catiônicos Antimicrobianos/biossíntese , Regulação da Expressão Gênica/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Peptídeos Catiônicos Antimicrobianos/genética , Feminino , Humanos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , beta-Defensinas/biossíntese , beta-Defensinas/genética , CatelicidinasRESUMO
In spite of advances in immunology on mycobacterial infection, there are few studies on the role of anti-microbial peptides in tuberculosis. The cathelin-related anti-microbial peptide (CRAMP) is the only cathelicidin isolated from mice. In this work we investigated the cellular sources and the production kinetics of this molecule during experimental tuberculosis, using two well-characterized models of latent or chronic infection and progressive disease. The lung of non-infected control mice expressed CRAMP at very low levels. In both models of experimental tuberculosis the main cells immunolabelled for CRAMP were bronchial epithelial cells, macrophages and pneumocytes types II and I. After intratracheal infection with a high bacilli dose (H37Rv strain) in Balb/c mice to produce progressive disease, a high CRAMP gene expression was induced showing three peaks: very early after 1 day of infection, at day 21 when the peak of protective immunity in this model is raised, and at day 28 when the progressive phase starts and the immunoelectronmicroscopy study showed intense immunolabelling in the cell wall and cytoplasm of intracellular bacilli, as well as in cytoplasmic vacuoles. Interestingly, at day 60 post-infection, when advanced progressive disease is well established, characterized by high bacillary loads and extensive tissue damage, CRAMP gene expression decreased but strong CRAMP immunostaining was detected in vacuolated macrophages filled with bacilli. Thus, cathelicidin is highly produced during experimental pulmonary tuberculosis from diverse cellular sources and could have significant participation in its pathogenesis.