Burstad Kendal M, Cladis Dennis P, Vorland Colby J, Wastney Meryl E, Biruete Annabel, Dominguez James M, O'Neill Kalisha D, Chen Neal X, Moe Sharon M, Hill Gallant Kathleen M
Department of Food Science and Nutrition University of Minnesota Saint Paul MN USA.
Department of Nutrition Science Purdue University West Lafayette IN USA.
JBMR Plus. 2022 Nov 16;6(12):e10698. doi: 10.1002/jbm4.10698. eCollection 2022 Dec.
Dietary phosphorus restriction and phosphorus binders are commonly prescribed for patients with chronic kidney disease (CKD). However, occurrences of non-adherence to these interventions are common. As low-phosphorus (LP) diets have been consistently experimentally shown in vitro to increase intestinal phosphorus absorption efficiency, a bout of non-adherence to diet or binders may cause an unintended consequence of enhanced intestinal phosphorus absorption. Thus, we aimed to determine the effect of a single bout of high-phosphorus (HP) intake after acclimation to a LP diet. Male Sprague Dawley rats with 5/6 nephrectomy ( = 36) or sham operation ( = 36) were block-randomized to 1 of 3 diets: LP (0.1% P w/w), HP (1.2%), or LP followed by acute HP (LPHP 0.1% then 1.2%). Phosphorus absorption tests were conducted using P radioisotope administrated by oral gavage or intravenously (iv). Although the overall two-way ANCOVA model for intestinal fractional phosphorus absorption was non-significant, exploratory comparisons showed intestinal fractional phosphorus absorption efficiency tended to be higher in rats in the LP compared with HP or LPHP groups. Rats in the HP or LPHP groups had higher plasma phosphorus compared with rats in the LP group, but the LPHP group was not different from the HP group. Gene expression of the major intestinal phosphate transporter, NaPi-2b, was lower in the jejunum of rats in the LPHP group compared with rats in the HP group but not different in the duodenum. These results demonstrate that an acute HP load after acclimation to a LP diet does not lead to enhanced intestinal fractional phosphorus absorption efficiency in 5/6 nephrectomized male rats. These data provide evidence against the notion that dietary phosphorus restriction or binder use adversely increases absorption efficiency after a single instance of dietary or binder non-adherence. However, other adverse consequences of fluctuating dietary phosphorus intake cannot be ruled out. © 2022 The Authors. published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
对于慢性肾脏病（CKD）患者，通常会开具饮食磷限制和磷结合剂的处方。然而，不遵守这些干预措施的情况很常见。由于低磷（LP）饮食在体外实验中一直显示会提高肠道磷吸收效率，一次不遵守饮食或结合剂规定可能会导致肠道磷吸收增强这一意外后果。因此，我们旨在确定在适应LP饮食后单次摄入高磷（HP）的影响。将36只进行了5/6肾切除术的雄性Sprague Dawley大鼠或36只假手术大鼠随机分为3种饮食组中的1组：LP（0.1%磷，w/w）、HP（1.2%）或先LP后急性HP（LPHP，先0.1%然后1.2%）。使用经口灌胃或静脉注射（iv）给予的P放射性同位素进行磷吸收测试。尽管肠道磷吸收分数的总体双向协方差分析模型无显著差异，但探索性比较显示，与HP或LPHP组相比，LP组大鼠的肠道磷吸收分数效率往往更高。HP或LPHP组大鼠的血浆磷水平高于LP组大鼠，但LPHP组与HP组无差异。与HP组大鼠相比，LPHP组大鼠空肠中主要肠道磷酸盐转运体NaPi-2b的基因表达较低，但在十二指肠中无差异。这些结果表明，在适应LP饮食后，一次急性HP负荷不会导致5/6肾切除雄性大鼠的肠道磷吸收分数效率提高。这些数据提供了证据，反驳了饮食磷限制或使用结合剂在单次饮食或结合剂不遵守后会不利地提高吸收效率的观点。然而，不能排除饮食磷摄入量波动的其他不良后果。© 2022作者。由Wiley Periodicals LLC代表美国骨与矿物质研究学会出版。
