RESUMO
Inflammatory bowel disease consists of multifactorial diseases whose common manifestation is inflammation of the gastrointestinal tract and their pathogenesis remains unknown. This study aimed to analyse the gene polymorphisms in Brazilian patients with inflammatory bowel disease. A total of 101 patients diagnosed with inflammatory bowel disease were analysed for the tumour necrosis factor-alpha (-308 G/A; rs1800629) and interleukin-10 (-1082 G/A; rs1800896) gene polymorphisms. Genotyping was performed through polymerase chain reaction-sequence-specific primer, then fractionated on 2% agarose gel and visualized after staining by ethidium bromide. The anatomic-clinical form of Crohn's disease (CD) predominant was the inflammatory (32.75%), followed by fistulizing (29.31%) and 27.58% stricturing. As control group, a total of 136 healthy subjects, from the same geographical region, were enrolled. The statistical analyses were performed using R program. The frequency of the A allele at tumour necrosis factor-alpha was high in ulcerative colitis (UC) patients (51%) than in controls (22%; P > 0.01). No statistical difference was found with the genotypic and allelic frequencies of CD patients compared to controls (P = 0.54). The polymorphism -1082G/A of interleukin-10 was not statistical different between the diseases compared to controls. Tumour necrosis factor-alpha (TNF-α) (-308G/A) is associated with UC onset, suggesting that the presence of -308A allele could confer a relative risk of 3.62 more to develop UC in general population. Further studies, increasing the number of individuals, should be performed to ratify the role of TNF-α in the inflammatory bowel disease pathogenesis.
Assuntos
Colite Ulcerativa/genética , Doença de Crohn/genética , Estudos de Associação Genética , Doenças Inflamatórias Intestinais/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Colite Ulcerativa/patologia , Doença de Crohn/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Doenças Inflamatórias Intestinais/patologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras GenéticasRESUMO
BACKGROUND: Epidemiological studies have indicated the lack of breast feeding as a risk factor associated with later development of inflammatory bowel disease. Nevertheless, the repercussion of little feeding during suckling on large intestine inflammatory response and anti-oxidant resources has not yet been completely understood. This study hypothesized that unfavorable lactation is able to induce oxidative stress and release of inflammatory mediators modifying the integrity of the colon epithelium in weanling rats. METHODS: Wistar rats were reared under different early nutritional conditions according to litter size in two groups: N6 (6 pups/dam) and N15 (15 pups/dam) until the 25th postnatal day. The distal colon was removed and processed for biochemical, morphometric, and immunohistochemical analyzes. Lipoperoxidation, nitric oxide (NO), reduced (GSH) and oxidized (GSSG) glutathione, tumor necrosis factor-alpha (TNF-α), interleukins-1ß, 4 and 10 (IL-1ß; IL-4; IL-10) levels, and total superoxide dismutase (tSOD), and catalase (CAT) activities were assessed. Morphometric analysis was carried out using paraffin sections and wholemount myenteric plexus preparations. KEY RESULTS: Increased lipoperoxidation, NO, TNF-α and IL-1b levels, reduced tSOD and increased CAT activities were found in the N15 compared to N6 group. No intergroup difference was detected for IL-10, while lower levels of IL-4, GSH and GSSG and lower neuronal size and density were induced by undernutrition. CONCLUSIONS & INFERENCES: Reduced feeding during suckling changed the inflammatory response and oxidative status in the colon of weanling rats. These data suggest potential mechanisms by which malnutrition early in life may increase the vulnerability of the large intestine to insults.