Sodium Butyrate Attenuates Diarrhea in Weaned Piglets and Promotes Tight Junction Protein Expression in Colon in a GPR109A-Dependent Manner
Sodium Butyrate Attenuates Diarrhea in Weaned Piglets and Promotes Tight Junction Protein Expression in Colon in a GPR109A-Dependent Manner
复制标题
丁酸钠以 GPR109A 依赖性方式减轻断奶仔猪腹泻并促进结肠中紧密连接蛋白的表达
DOI：
10.1159/000490981
复制
发表时间：
2018-01-01
影响因子：
--
通讯作者：
Liu, Juxiong
中科院分区：
文献类型：
--
作者：
Feng, Wenqian;Wu, Yancheng;Liu, Juxiong
背景/目的：丁酸在维持肠道健康中起着重要作用。丁酸作为一种短链脂肪酸受到了特别的关注，但其在保护肠道屏障方面的作用却很少。丁酸不仅为上皮细胞提供能量，还作为组蛋白脱乙酰酶抑制剂;它也是G蛋白偶联受体109 A（GPR 109 A）的天然配体。GPR 109 A类似物在野猪中表达并介导β-羟基丁酸的抗炎作用。本研究探讨了丁酸盐对21日龄断奶仔猪生长性能、腹泻症状和紧密连接蛋白水平的影响。我们还研究了丁酸调节肠道通透性的机制。研究方法：选用21日龄断奶仔猪24头，随机分为基础日粮组和丁酸钠+基础日粮组。饲喂3周后观察腹泻率、生长性能，采用高效液相色谱法检测尿中乳果糖/甘露醇比值，实时荧光定量PCR或蛋白质印迹法检测肠道紧密连接蛋白和结肠中GPR 109 A、Akt等相关信号分子的表达水平。Caco-2细胞被用作结肠细胞模型，并在有或没有丁酸钠的情况下培养，以评估紧密连接蛋白的表达和相关信号分子的活化。GPR 109 A短发夹RNA（shRNA）和Akt和ERK 1/2的特异性拮抗剂被用作信号通路抑制剂，以阐明丁酸调节紧密连接蛋白表达和结肠上皮屏障的机制。结果如下：丁酸钠日粮可减轻早期断奶仔猪的腹泻症状，降低肠道通透性，但不影响仔猪的生长。紧密连接蛋白Claudin-3、Occludin和闭合小带1的表达水平在结肠和Caco-2细胞中被丁酸钠上调。在Caco-2细胞中使用shRNA敲低GPR 109 A或阻断Akt信号通路抑制丁酸钠诱导的Claudin-3表达。结论：丁酸钠以GPR 109 A依赖的方式作用于Akt信号通路，促进Claudin-3在结肠的表达。
Background/Aims: Butyric acid plays an important role in maintaining intestinal health. Butyric acid has received special attention as a short-chain fatty acid, but its role in protecting the intestinal barrier is poorly characterized. Butyric acid not only provides energy for epithelial cells but also acts as a histone deacetylase inhibitor; it is also a natural ligand for G protein-coupled receptor 109A (GPR109A). A GPR109A analog was expressed in Sus scrofa and mediated the anti-inflammatory effects of beta-hydroxybutyric acid. This study investigated the effects of butyrate on growth performance, diarrhea symptoms, and tight junction protein levels in 21-day-old weaned piglets. We also studied the mechanism by which butyric acid regulates intestinal permeability. Methods: Twenty-four piglets that had been weaned at an age of 21 days were divided randomly into 2 equal groups: basal diet group and sodium butyrate + basal diet group. Diarrhea rate, growth performance during 3 weeks of feeding on these diets were observed, the lactulose-mannitol ratio in urine were detected by High Performance Liquid Chromatography, the expression levels of tight junction proteins in the intestinal tract and related signaling molecules, such as GPR109A and Akt, in the colon were examined by quantitative real-time PCR or western blot analyses on day 21. Caco-2 cells were used as a colon cell model and cultured with or without sodium butyrate to assess the expression of tight junction proteins and the activation of related signaling molecules. GPR109A-short hairpin RNA (shRNA) and specific antagonists of Akt and ERK1/2 were used as signaling pathway inhibitors to elucidate the mechanism by which butyric acid regulates the expression of tight junction proteins and the colonic epithelial barrier. Results: The sodium butyrate diet alleviated diarrhea symptoms and decreased intestinal permeability without affecting the growth of early weaned piglets. The expression levels of the tight junction proteins Claudin-3, Occludin, and zonula occludens 1 were up-regulated by sodium butyrate in the colon and Caco-2 cells. GPR109A knockdown using shRNA or blockade of the Akt signaling pathway in Caco-2 cells suppressed sodium butyrate-induced Claudin-3 expression. Conclusions: Sodium butyrate acts on the Akt signaling pathway to facilitate Claudin-3 expression in the colon in a GPR109A-dependent manner.