背景:肠易激综合征(IBS)是一种肠动力改变的多因素疾病,分泌,和感觉。5-羟色胺(5-HT)刺激肠道运动并改变5-羟色胺信号,这可能导致IBS的肠道和肠外症状。
目的:本研究的目的是研究IBS中5-羟色胺转运体基因启动子多态性(5-HTTLPR)与乳果糖氢呼气试验测量的口肠转运时间(OCTT)的相关性。
方法:这项前瞻性病例对照研究包括151例IBS患者(平均±SD37.4±11.6年,中位数36,范围19-68)。92例患者为腹泻型IBS(D-IBS),44便秘型IBS(C-IBS),15交替腹泻和便秘IBS(M-IBS),和100名健康对照(平均值±SD37.2±11.4年,中位数36,范围20-64岁)。通过基于聚合酶链反应的方法研究5-HTTLPR基因多态性。通过酶联免疫吸附测定(ELISA)测量5-HT水平。通过非侵入性乳果糖氢呼气试验测量食道通过时间(OCTT)。还将OCTT与不同IBS表型中的5-HTTLPR基因型进行了比较。
结果:所有IBS患者的血清5-羟色胺水平明显升高(152±77ng/mL,p<0.001),D-IBS(184±76ng/mL,p<0.001),与健康对照组相比(129±56ng/mL)。C-IBS(124±53ng/mL)和对照组之间的5-HT水平没有差异。在M-IBS的情况下,5-HT水平(88±49ng/mL,p<0.05)明显低于对照组。与对照组(112±41分钟)相比,D-IBS患者的OCTT显着缩短(95±36分钟)。相比之下,C-IBS显示OCTT显著延长(136±54分钟)。D-IBS和C-IBS患者的OCTT存在显著差异(p<0.001)。在OCTT和5-HTTLPR之间没有发现显著关联。
结论:与对照组和C-IBS相比,D-IBS的血清5-羟色胺浓度升高。D-IBS患者的OCTT较短,C-IBS患者的OCTT延迟。5-HTLPR多态性与OCTT无关。
Irritable bowel syndrome (IBS) is a multifactorial disorder with altered intestinal motility, secretion, and sensation. Serotonin (5-HT) stimulates gut motility and alters serotonin signaling that may lead to both intestinal and extraintestinal symptoms in IBS.
The aim of this study was to examine the association of serotonin transporter gene promoter polymorphism (5-HTTLPR) in IBS with orocecal transit time (OCTT) measured by lactulose hydrogen breath test.
This prospective case-control study included 151 IBS patients (mean±SD 37.4±11.6 years, median 36, range 19-68). Ninety-two patients were diarrhea-predominant IBS (D-IBS), 44 constipation-predominant IBS (C-IBS), 15 alternating diarrhea and constipation IBS (M-IBS), and 100 healthy controls (mean±SD 37.2±11.4 years, median 36, range 20-64 years). 5-HTTLPR gene polymorphism was studied by polymerase chain reaction-based method. 5-HT levels were measured by enzyme-linked immunosorbent assay (ELISA). Orocecal transit time (OCTT) was measured by a non-invasive lactulose hydrogen breath test. OCTT was also compared with respect to 5-HTTLPR genotypes in different IBS phenotypes.
Serum serotonin levels were significantly higher in overall IBS patients (152±77 ng/mL, p<0.001), D-IBS (184±76 ng/mL, p<0.001), compared to healthy controls (129±56 ng/mL). There was no difference in 5-HT levels between C-IBS (124±53 ng/mL) and controls. In the case of M-IBS, 5-HT levels were (88±49 ng/mL p<0.05) significantly lower than that of controls. OCTT was significantly shorter in D-IBS patients (95±36 min) as compared to controls (112±41 min). In contrast, C-IBS showed significantly prolonged OCTT (136±54 min). There was a significant difference in OCTT between D-IBS and C-IBS patients (p<0.001). There was no significant association found between OCTT and 5-HTTLPR.
Serum serotonin concentrations were increased in D-IBS compared to controls and C-IBS. OCTT was shorter in D-IBS and delayed in C-IBS patients. There was no association of 5-HTLPR polymorphism with OCTT.