Laboratory of Nutrigenomics, Inflammation and Obesity Research, Department of Nutritional Sciences, Texas Tech University (TTU), Lubbock, TX 79409-1270, USA.
Obesity Research Institute, Texas Tech University, Lubbock, TX 79409-1270, USA.
Nutrients. 2022 Jun 22;14(13):2583. doi: 10.3390/nu14132583.
(1) Consumption of diets that are caloric dense but not nutrient dense have been implicated in metabolic diseases, in part through low-grade metabolic acidosis. Mitigation strategies through dietary intervention to alleviate acidosis have not been previously reported. Our objective is to determine the effects of pH enhancement (with ammonia) in high fat diet-induced obese mice that were fed beef or casein as protein sources compared to low fat diet-fed mice. (2) Methods: B6 male and female mice were randomized ( = 10) into eight diets that differ in protein source, pH enhancement of the protein, and fat content, and fed for 13 weeks: low fat (11% fat) casein (LFC), LF casein pH-enhanced (LFCN), LF lean beef (LFB), LFBN, high fat (46%) casein (HFC), HFCN, HF beef (HFB), and HFBN. Body weights and composition, and glucose tolerance tests were conducted along with terminal serum analyses. Three-way ANOVA was performed. (3) Results: A significant effect of dietary fat (LF vs. HF) was observed across all variables in both sexes (final body weight, fat mass, glucose clearance, and serum leptin). Importantly, pH enhancement significantly reduced adiposity (males only) and final body weights (females only) and significantly improved glucose clearance in both sexes. Lastly, clear sex differences were observed across all variables. (4) Conclusions: Our findings demonstrate metabolic benefits of increasing dietary pH using ammonia, while high fat intake per se (not protein source) is the major contributor to metabolic dysfunctions. Additional research is warranted to determine mechanisms underlying the beneficial effects of pH enhancement, and interactions with dietary fat content and proteins.
（1）高热量但营养密度低的饮食与代谢疾病有关，部分原因是低度代谢性酸中毒。通过饮食干预来减轻酸中毒的缓解策略以前没有报道过。我们的目的是确定在高脂肪饮食诱导肥胖的小鼠中增强 pH 值（用氨）的效果，这些小鼠以牛肉或酪蛋白作为蛋白质来源，与低脂肪饮食喂养的小鼠进行比较。
（2）方法：B6 雄性和雌性小鼠被随机分为 8 种不同蛋白质来源、蛋白质 pH 值增强和脂肪含量的饮食组（每组 10 只），并喂养 13 周：低脂肪（11%脂肪）酪蛋白（LFC）、LF 酪蛋白 pH 增强（LFCN）、LF 瘦牛肉（LFB）、LFBN、高脂肪（46%）酪蛋白（HFC）、HFCN、HF 牛肉（HFB）和 HFBN。进行体重和成分以及葡萄糖耐量试验以及终末血清分析。进行三因素方差分析。
（3）结果：在雄性和雌性小鼠中，饮食脂肪（LF 与 HF）对所有变量都有显著影响（最终体重、脂肪量、葡萄糖清除率和血清瘦素）。重要的是，pH 值增强显著降低了肥胖（仅男性）和最终体重（仅女性），并显著改善了两性的葡萄糖清除率。最后，观察到所有变量都有明显的性别差异。
（4）结论：我们的研究结果表明，使用氨增加膳食 pH 值具有代谢益处，而高脂肪摄入本身（而不是蛋白质来源）是导致代谢功能障碍的主要原因。需要进一步研究来确定 pH 值增强的有益效果的机制，以及与饮食脂肪含量和蛋白质的相互作用。
