IL-10 and TNF-alpha polymorphisms in subjects with irritable bowel syndrome in Mexico.

BACKGROUND: there has been recent evidence of an alteration in irritable bowel syndrome (IBS) immune regulation, as well as variations in cytokine polymorphisms. AIMS: to determine the frequency of the IL-10 (-1082G/A) and TNF-alpha (-308G/A) polymorphisms in subjects with IBS in Mexico. METHODS: volunteers answered the Rome II Questionnaire and were classified as IBS (n = 45) and controls (n = 92). The IBS subjects were then categorized as IBS-D: 22.2%, IBS-C: 28.9%, and IBS-A/M: 48.9%. The polymorphism frequency among groups was compared. RESULTS: there were no differences between IBS vs. controls in the frequency of the high (8.9 vs. 18.5%), intermediate (60.0 vs. 57.6%), or low (23.9 vs. 38.9%) producer IL-10 genotypes, p = 0.315. Neither were there differences in the high (0 vs. 1.1%), intermediate (55.4 vs. 43.2%), or low (43.5 vs. 56.8%) producer TNF-alpha genotypes, p = 0.296. However the low producer of IL-10 was more frequent in IBS-D vs. IBS-C vs. IBS-A/M (63.6 vs. 7.1 vs. 33,3%) p = 0.023. CONCLUSIONS: in this group of volunteers in Mexico, the frequency of the IL-10 (-1082G/A) and TNF-alpha (-308G/A) genotypes was similar in IBS and controls. However, there was a greater frequency of the low producer of IL-10 in those subjects with IBS-D, suggesting a genetic predisposition to abnormal immune regulation due to a lower anti-inflammatory component in this subgroup.

Polimorfismos de IL-10 y TNF-alfa en sujetos con síndrome de intestino irritable en México / IL-10 and TNF-alpha polymorphisms in subjects with irritable bowel syndrome in Mexico

Antecedentes: evidencias recientes han mostrado una alteración en la regulación inmune en el síndrome de intestino irritable (SII) así como variaciones en los polimorfismos de citocinas. Objetivos: determinar la frecuencia de polimorfismos IL-10 (-1082G/A) y TNF-alpha (-308G/A) en sujetos con SII en México. Métodos: sujetos voluntarios contestaron el Cuestionario de Roma II y fueron clasificados como SII (n = 45) y controles (n = 92). Aquellos con SII fueron a su vez clasificados en SII-D: 22,2 %, SII-E: 28,9 % y SII-A/M: 48,9 %. Se comparó la frecuencia de los polimorfismos entre los grupos. Resultados: no hubo diferencias entre SII vs. controles en la frecuencia del genotipo alto (8,9 vs. 18,5 %), intermedio (60,0 vs. 57,6 %) y bajo productor (23,9 vs. 38,9 %) de IL-10, p = 0,315. Tampoco en alto (0 vs. 1,1 %), intermedio (55,4 vs. 43,2 %) o bajo productor (43,5 vs. 56,8 %) de TNF-alpha, p = 0,296. Sin embargo, el bajo productor de IL-10 fue más frecuente en SII-D vs. SII-E vs. SII-A/M (63,6 vs. 7,1 vs. 33,3 %) p = 0,023. Conclusiones: en este grupo de voluntarios en México la frecuencia de genotipos de IL-10 (-1082G/A) y TNF-alpha (-308G/A) fue similar en SII y controles, pero aquellos con SII-D presentaron mayor frecuencia del bajo productor de IL-10 sugiriendo una predisposición genética a una regulación inmune anormal dada por un menor componente antiinflamatorio en este subgrupo (AU)

Background: there has been recent evidence of an alteration in irritable bowel syndrome (IBS) immune regulation, as well as variations in cytokine polymorphisms. Aims: to determine the frequency of the IL-10 (-1082G/A) and TNF-áalpha(-308G/A) polymorphisms in subjects with IBS in Mexico. Methods: volunteers answered the Rome II Questionnaire and were classified as IBS (n = 45) and controls (n = 92). The IBS subjects were then categorized as IBS-D: 22.2 %, IBS-C: 28.9 %, and IBS-A/M: 48.9 %. The polymorphism frequency among groups was compared. Results: there were no differences between IBS vs. controls in the frequency of the high (8.9 vs. 18.5 %), intermediate (60.0 vs. 57.6 %), or low (23.9 vs. 38.9 %) producer IL-10 genotypes, p = 0.315. Neither were there differences in the high (0 vs. 1.1 %), intermediate (55.4 vs. 43.2 %), or low (43.5 vs. 56.8 %) producer TNF-alpha genotypes, p = 0.296. However the low producer of IL-10 was more frequent in IBS-D vs. IBS-C vs. IBS-A/M (63.6 vs. 7.1 vs. 33,3 %) p = 0.023. Conclusions: in this group of volunteers in Mexico, the frequency of the IL-10 (-1082G/A) and TNF-alpha (-308G/A) genotypes was similar in IBS and controls. However, there was a greater frequency of the low producer of IL-10 in those subjects with IBS-D, suggesting a genetic predisposition to abnormal immune regulation due to a lower anti-inflammatory component in this subgroup (AU)

Lower serum IL-10 is an independent predictor of IBS among volunteers in Mexico.

OBJECTIVES: Studies suggest that altered immune activation, manifested by an imbalance in anti- and pro-inflammatory cytokine levels, exists in a subgroup of irritable bowel syndrome (IBS) patients. However, similar studies have not been conducted in Latin populations. The objective of this study was to measure serum levels of interleukin (IL)-10 and tumor necrosis factor (TNF)-α in subjects fulfilling symptom criteria for IBS and controls. METHODS: Volunteers (n=178) from a university population in Mexico City, participated in the study. Of the sample, 34.8% met Rome II criteria for IBS and 65.2% were designated as controls. Serum cytokines were measured by enzyme-linked immunoabsorbent assay. Analysis of covariance models were used to test main effects between gender, IBS symptoms, and bowel habit subtype to explain the cytokine serum levels. Statistical models were tested using body mass index as a covariate. RESULTS: IL-10 levels were significantly lower in IBS vs. controls (mean (95% confidence interval): 15.6 (14.8, 16.3) vs. 18.6 (17.9, 19.4) pg/ml, P<0.001), while TNF-α levels were higher in IBS (20.9 (19.1, 23.0) vs. 17.9 (16.7, 19.3) pg/ml, P=0.010). IBS and female gender were independent predictors for IL-10 (P<0.05). In contrast, female gender was an independent predictor for TNF-α. In addition, women with IBS-D had the lowest IL-10 (P<0.001) and highest TNF-α (P=0.021) vs. other subtypes. CONCLUSIONS: The lower serum IL-10 in our subjects fulfilling IBS Rome II symptom criteria suggests an altered immune regulation. Further studies are needed to elucidate if a lower serum IL-10 may be useful as a biomarker for IBS in the Mexican population, especially for women with IBS-D.