Younes H, Alphonse J C, Behr S R, Demigné C, Rémésy C
INRA, Centre de Recherches en Nutrition Humaine de Clermont-Ferrand/Theix, St-Genès-Champanelle, OH, USA.
Am J Kidney Dis. 1999 Apr;33(4):633-46. doi: 10.1016/s0272-6386(99)70213-1.
During the past few years, considerable attention has been given to the impact of nutrition on kidney disease. The question arises of whether the effect of a moderate dietary protein restriction could be reinforced by enrichment of the diet with fermentable carbohydrates. Feeding fermentable carbohydrates may stimulate the extrarenal route of nitrogen (N) excretion through the fecal route. Such an effect has been reported in several species, including healthy humans and patients with chronic renal failure (CRF). Furthermore, studies of these subjects show that the greater fecal N excretion during the fermentable carbohydrate supplementation period was accompanied by a significant decrease in plasma urea concentration. In animal models of experimental renal failure, the consumption of diets containing fermentable carbohydrates results in a greater rate of urea N transfer from blood to the cecal lumen, where it is hydrolyzed by bacterial urease before subsequent microflora metabolism and proliferation. Therefore, this results in a greater fecal N excretion, coupled with a reduction in urinary N excretion and plasma urea concentration. Because elevated concentrations of serum urea N have been associated with adverse clinical symptoms of CRF, these results suggest a possible usefulness of combining fermentable carbohydrates with a low-protein diet to increase N excretion through the fecal route. Further investigations in this population of patients of whether fermentable carbohydrates in the diet may be beneficial in delaying or treating the symptoms and chronic complications of CRF will certainly emerge in the future. This should be realized without adversely affecting nutritional status and, as far as possible, by optimizing protein intake for the patients without being detrimental to renal function.
在过去几年中，营养对肾脏疾病的影响已受到相当多的关注。一个问题随之而来：适度的膳食蛋白质限制的效果是否可以通过在饮食中添加可发酵碳水化合物来增强。摄入可发酵碳水化合物可能会刺激氮（N）通过粪便途径的肾外排泄途径。在包括健康人和慢性肾衰竭（CRF）患者在内的几个物种中都报道过这种效果。此外，对这些受试者的研究表明，在补充可发酵碳水化合物期间粪便氮排泄增加的同时，血浆尿素浓度显著降低。在实验性肾衰竭的动物模型中，食用含有可发酵碳水化合物的饮食会导致尿素氮从血液转移到盲肠腔的速率更高，在那里它在随后的微生物群代谢和增殖之前被细菌脲酶水解。因此，这导致粪便氮排泄增加，同时尿氮排泄和血浆尿素浓度降低。由于血清尿素氮浓度升高与CRF的不良临床症状有关，这些结果表明将可发酵碳水化合物与低蛋白饮食相结合以增加通过粪便途径的氮排泄可能是有用的。未来肯定会对这类患者群体进一步研究饮食中的可发酵碳水化合物是否有利于延缓或治疗CRF的症状和慢性并发症。这应该在不负面影响营养状况的情况下实现，并且尽可能通过优化患者的蛋白质摄入量而不损害肾功能来实现。
