Centre for Nutrition and Food Sciences, The University of Queensland, Hartley Teakle Building, St Lucia, Queensland 4072, Australia.
Food Funct. 2010 Nov;1(2):149-55. doi: 10.1039/c0fo00080a. Epub 2010 Sep 30.
A number of studies have shown a positive relationship between diets rich in soluble dietary fibres (SDF) such as β-glucan, pectin, guar gum and psyllium, and reduced serum cholesterol and thus a decreased risk of cardiovascular disease (CVD). Three major biological mechanisms have been proposed to explain the cholesterol-reducing effects of SDF: prevention of bile salt (BS) re-absorption from the small intestine leading to an excess faecal BS excretion; reduced glycemic response leading to lower insulin stimulation of hepatic cholesterol synthesis; and physiological effects of fermentation products of SDF, mainly propionate. Evidence for the latter mechanism is inconclusive, whereas in vivo, ex vivo and in vitro experiments suggest that BS micelles "bind" to SDF preventing their re-absorption. Whereas, glycemic responses to SDF have been studied extensively, the nature of interactions between bile salt micelles and SDF that lead to incomplete BS re-absorption are poorly defined. Three potential physicochemical mechanisms are proposed together with suggestions for in vitro experiments to test them.
许多研究表明，富含可溶性膳食纤维（SDF）的饮食，如β-葡聚糖、果胶、瓜尔胶和车前子，与血清胆固醇降低有关，从而降低了心血管疾病（CVD）的风险。有三种主要的生物学机制被提出来解释 SDF 的降低胆固醇作用：防止从小肠中重新吸收胆汁盐（BS），导致粪便 BS 排泄过多；降低血糖反应，从而降低胰岛素对肝脏胆固醇合成的刺激；SDF 发酵产物的生理作用，主要是丙酸。后一种机制的证据尚不确定，而在体内、离体和体外实验表明，BS 胶束“结合”到 SDF 上，阻止其再吸收。然而，人们对 SDF 的血糖反应进行了广泛的研究，但导致不完全 BS 再吸收的胆汁盐胶束与 SDF 之间相互作用的性质还没有得到很好的定义。本文提出了三种潜在的物理化学机制，并提出了体外实验来检验它们的建议。
