Short-term consumption of highly processed diets varying in macronutrient content impair the sense of smell and brain metabolism in mice.

Food processing greatly contributed to increased food safety, diversity, and accessibility. However, the prevalence of highly palatable and highly processed food in our modern diet has exacerbated obesity rates and contributed to a global health crisis. While accumulating evidence suggests that chronic consumption of such foods is detrimental to sensory and neural physiology, it is unclear whether its short-term intake has adverse effects. Here, we assessed how short-term consumption (<2 months) of three diets varying in composition and macronutrient content influence olfaction and brain metabolism in mice. The diets tested included a grain-based standard chow diet (CHOW; 54% carbohydrate, 32% protein, 14% fat; #8604 Teklad Rodent diet , Envigo Inc.), a highly processed control diet (hpCTR; 70% carbohydrate, 20% protein, 10% fat; #D12450B, Research Diets Inc.), and a highly processed high-fat diet (hpHFD; 20% carbohydrate, 20% protein, 60% fat; #D12492, Research Diets Inc.). We performed behavioral and metabolic phenotyping, electro-olfactogram (EOG) recordings, brain glucose metabolism imaging, and mitochondrial respirometry in different brain regions. We also performed RNA-sequencing (RNA-seq) in the nose and across several brain regions, and conducted differential expression analysis, gene ontology, and network analysis. We show that short-term consumption of the two highly processed diets, but not the grain-based diet, regardless of macronutrient content, adversely affects odor-guided behaviors, physiological responses to odorants, transcriptional profiles in the olfactory mucosa and brain regions, and brain glucose metabolism and mitochondrial respiration. Even short periods of highly processed food consumption are sufficient to cause early olfactory and brain abnormalities, which has the potential to alter food choices and influence the risk of developing metabolic disease. Short-term ingestion of highly processed diets adversely affects olfaction. Highly processed diets dysregulate the transcriptional profiles of the nose and brain. Short-term ingestion of highly processed diets affects brain metabolism and connectivity. Brain mitochondrial function is mildly affected by highly processed diets.

食品加工极大地促进了食品安全、多样性和可获取性的提升。然而，在我们现代饮食中，高美味度和高度加工食品的盛行加剧了肥胖率，并导致了一场全球健康危机。虽然越来越多的证据表明，长期食用此类食品对感官和神经生理有害，但尚不清楚短期摄入是否有不良影响。在此，我们评估了三种成分和常量营养素含量不同的饮食在短期（<2个月）食用情况下如何影响小鼠的嗅觉和大脑代谢。 所测试的饮食包括一种以谷物为基础的标准饲料饮食（CHOW；54%碳水化合物，32%蛋白质，14%脂肪；#8604特克拉德啮齿动物饲料，Envigo公司），一种高度加工的对照饮食（hpCTR；70%碳水化合物，20%蛋白质，10%脂肪；#D12450B，研究饮食公司），以及一种高度加工的高脂肪饮食（hpHFD；20%碳水化合物，20%蛋白质，60%脂肪；#D12492，研究饮食公司）。我们在不同的大脑区域进行了行为和代谢表型分析、嗅电图（EOG）记录、大脑葡萄糖代谢成像以及线粒体呼吸测定。我们还在鼻子和几个大脑区域进行了RNA测序（RNA - seq），并进行了差异表达分析、基因本体论和网络分析。 我们表明，短期食用两种高度加工的饮食（而非以谷物为基础的饮食），无论常量营养素含量如何，都会对气味引导的行为、对气味物质的生理反应、嗅黏膜和大脑区域的转录谱，以及大脑葡萄糖代谢和线粒体呼吸产生不利影响。 即使是短期食用高度加工食品也足以导致早期的嗅觉和大脑异常，这有可能改变食物选择并影响患代谢疾病的风险。 短期摄入高度加工的饮食对嗅觉有不利影响。 高度加工的饮食会失调鼻子和大脑的转录谱。 短期摄入高度加工的饮食会影响大脑代谢和连接性。 大脑线粒体功能受到高度加工饮食的轻度影响。