Luciano L, Busche R, von Engelhardt W, Reale E
Zentrum Anatomie, Abteilung Zellbiologie, Medizinische Hochschule Hannover, Germany.
Ital J Anat Embryol. 2001;106(2 Suppl 1):347-52.
Short-chain fatty acids (SCFA) in particular butyrate are regarded as an energy source acting in beneficial, protective manner on the colonic mucosa. Previous investigations showed that the colonic mucosa bathed in Ussing chamber with a solution lacking butyrate induced massive apoptosis of epithelial cells. The apoptotic material (bodies and cells) was shed at the mucosa surface. In the present study we aimed to investigate the effects caused in vivo on the colonic mucosa by the absence of butyrate. For this purpose the colon of guinea pigs was perfused in situ with solutions either containing or lacking butyrate. The results show that within 2h of perfusion without butyrate a large amount of epithelial cells underwent apoptosis as in the in vitro experiments. However, apoptotic material instead to be extruded at the epithelial surface accumulates into the intercellular spaces from which it becomes removed by an unusual high number of macrophages. These, engorged with phagocytozed material, lie assembled in a layer below the epithelium. Similar alterations have not been observed after perfusion in the presence of butyrate. The results suggest that this SCFA may protect the colonic mucosa in that it prevents apoptosis. The alterations occurring during 2h of its absence allow to assume that a protracted butyrate deprivation may lead to a breakdown of the integrity of the mucosa thus influencing differently the activity of the macrophages.
短链脂肪酸（SCFA）尤其是丁酸，被视为一种对结肠黏膜具有有益保护作用的能量来源。先前的研究表明，在尤斯灌流室中用缺乏丁酸的溶液浸泡结肠黏膜会诱导上皮细胞大量凋亡。凋亡物质（小体和细胞）会在黏膜表面脱落。在本研究中，我们旨在探究体内缺乏丁酸对结肠黏膜所造成的影响。为此，我们对豚鼠的结肠进行原位灌注，灌注液分别含有或缺乏丁酸。结果表明，在无丁酸灌注的2小时内，大量上皮细胞如同在体外实验中一样发生凋亡。然而，凋亡物质并未像在体外实验中那样被挤出上皮表面，而是积聚在细胞间隙中，随后被数量异常多的巨噬细胞清除。这些巨噬细胞吞噬了大量物质，聚集在上皮下方形成一层。在有丁酸存在的情况下进行灌注后未观察到类似变化。结果表明，这种短链脂肪酸可能通过防止凋亡来保护结肠黏膜。在缺乏丁酸的2小时内所发生的变化表明，长期缺乏丁酸可能导致黏膜完整性破坏，从而对巨噬细胞的活性产生不同影响。
