Laboratory of Clinical Nutrition and Management, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan.
Laboratory of Clinical Nutrition and Management, Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan; Department of Human and Nutrition, School of Life Studies, Sugiyama Jogakuen University, Nagoya, Japan.
Nutrition. 2020 Apr;72:110694. doi: 10.1016/j.nut.2019.110694. Epub 2019 Dec 6.
The ratio of dietary carbohydrate to fat may affect phosphorus metabolism because both calcium and phosphorus are regulated by similar metabolic mechanisms, and a high-fat diet (HFD) induces deleterious effects on the absorption of dietary calcium. We hypothesized that an HFD induces an increase in phosphorus absorption. The aim of this study was to evaluate the effects of differences in the quantity and quality of dietary fat on phosphorus metabolism over the short- and long-term.
Eighteen 8-wk-old Sprague-Dawley male rats were fed an isocaloric diet containing varied ratios of carbohydrates to fat energy and sources of fat (control diet, HFD, and high- saturated fat diet [HF-SFA]). At 3 d and 7 wk after the allocation and initiation of the test diets, feces and urine were collected and used for phosphorus and calcium measurement.
The fecal phosphorous concentration (F-Pi) was lower in the HF-SFA group than in the other two groups; however, the urine phosphorus concentration (U-Pi) was significantly higher in the HF-SFA group than the other two groups when the rats were fed over the short- (P < 0.01) and long -term (P < 0.01 versus control, P < 0.05 versus HFD group). There were no significant differences in type-IIa sodium-phosphate cotransporter (NaPi-2 a) and type-IIc sodium-phosphate cotransporter (NaPi-2 c) mRNA expression, which are renal phosphate transport-related genes; however, the expression of type-IIb sodium-phosphate cotransporter (NaPi-2 b) and type-III sodium-phosphate cotransporter (Pit-1) mRNA in the duodenum was higher in the HFD and HF-SFA groups than in the control group (P < 0.05), although there were no significant differences in these in the jejunum.
The present results indicated that an HFD, particularly HF-SFA, increases intestinal phosphate absorption compared with control.
饮食中碳水化合物与脂肪的比例可能会影响磷代谢，因为钙和磷受类似的代谢机制调节，而高脂肪饮食（HFD）会对膳食钙的吸收产生有害影响。我们假设 HFD 会导致磷吸收增加。本研究旨在评估短期和长期内不同数量和质量的脂肪对磷代谢的影响。
将 18 只 8 周龄的 Sprague-Dawley 雄性大鼠喂食等热量的含有不同碳水化合物与脂肪能量比和脂肪来源的饮食（对照饮食、HFD 和高饱和脂肪饮食[HF-SFA]）。在分配和开始测试饮食后的 3 天和 7 周时，收集粪便和尿液用于磷和钙的测量。
HF-SFA 组的粪便磷浓度（F-Pi）低于其他两组；然而，当大鼠短期（P<0.01）和长期（与对照相比，P<0.01；与 HFD 组相比，P<0.05）喂食时，HF-SFA 组的尿磷浓度（U-Pi）显著高于其他两组。IIa 型钠磷共转运体（NaPi-2a）和 IIc 型钠磷共转运体（NaPi-2c）mRNA 表达无显著差异，这是与肾脏磷转运相关的基因；然而，HFD 和 HF-SFA 组十二指肠中 IIb 型钠磷共转运体（NaPi-2b）和 Pit-1 型钠磷共转运体（Pit-1）mRNA 的表达高于对照组（P<0.05），尽管空肠中无显著差异。
本研究结果表明，HFD，特别是 HF-SFA，与对照相比增加了肠道磷吸收。
