LAQV/REQUIMTE, Department of Chemical Sciences, Laboratory of Food Science and Hydrology, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; LAQV/REQUIMTE, ICBAS, School of Medicine and Biomedical Sciences, University of Porto, Rua de Jorge Viterbo, Ferreira 228, 4050-313 Porto, Portugal.
LAQV/REQUIMTE, Department of Chemical Sciences, Laboratory of Food Science and Hydrology, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
Food Res Int. 2023 Apr;166:112576. doi: 10.1016/j.foodres.2023.112576. Epub 2023 Feb 6.
The stomach is a relevant spot of lipolysis for milk fat, but research on the effect of digested milk fat in the gastric epithelium is scarce and difficult to evaluate. In the present study, we implemented the semi-dynamic in vitro digestion model of INFOGEST, combined with gastric NCI-N87 cells, to study the effect of fat-free, whole conventional, and whole pasture-based milk on gastric epithelium. Cellular messenger ribonucleic acid (mRNA) expression of membrane fatty acids receptors (GPR41, GPR84), antioxidant enzymes (CAT, SOD, GPX), and inflammatory molecules (NF-κB p65, IL-1β, IL-6, IL-8 and TNF-α) was assessed. No significant differences were observed in mRNA expression of GPR41, GPR84, SOD, GPX, IL-6, IL-8, and TNF-α, after exposure of the NCI-N87 cells to milk digesta samples (p > 0.05). An increase of CAT mRNA expression was observed (p < 0.05), at a similar level, for all milk types. Whole milk digested samples induced higher mRNA expression of NF-κB p65 and IL-1β than fat-free milk (p < 0.05); while no differences were observed between whole conventional and whole pasture-based milk (p > 0.05). Moreover, the effect of milk digesta on gastric mRNA expression was studied in a scenario of subsequent stimulation of NCI-N87 monolayer with the pro-inflammatory cytokine IFN-γ. In these conditions, milk digesta samples increased CAT mRNA expression (p < 0.05), but had no effect in the expression of NF-κB p65 and IL-1β (p > 0.05). The increase of CAT mRNA expression suggests that milk fatty acids are used for energy production by gastric epithelial cells. Cellular antioxidant response to higher milk fatty acids availability could be associated to gastric epithelial inflammation, but did not contribute to increased inflammation in case of an external contact with IFN-γ. Besides, a conventional or a pasture-based origin did not affect the impact of whole milk in the NCI-N87 monolayer. The combined model responded to differences in milk fat content, which indicates its usefulness to study effects of foods at the gastric level.
胃是乳脂脂肪分解的相关部位，但关于消化乳脂在胃上皮细胞中的作用的研究很少且难以评估。在本研究中，我们实施了 INFOGEST 的半动态体外消化模型，结合胃 NCI-N87 细胞，研究无脂、全常规和全草饲牛奶对胃上皮细胞的影响。评估了膜脂肪酸受体 (GPR41、GPR84)、抗氧化酶 (CAT、SOD、GPX) 和炎症分子 (NF-κB p65、IL-1β、IL-6、IL-8 和 TNF-α) 的细胞信使核糖核酸 (mRNA) 表达。在 NCI-N87 细胞暴露于奶消化物样品后，GPR41、GPR84、SOD、GPX、IL-6、IL-8 和 TNF-α 的 mRNA 表达没有观察到显著差异 (p > 0.05)。CAT mRNA 表达增加 (p < 0.05)，所有牛奶类型的水平相似。全脂奶消化物样品诱导的 NF-κB p65 和 IL-1β mRNA 表达高于无脂奶 (p < 0.05)；而全常规奶和全草饲奶之间没有差异 (p > 0.05)。此外，还研究了在随后用促炎细胞因子 IFN-γ刺激 NCI-N87 单层的情况下，奶消化物对胃 mRNA 表达的影响。在这些条件下，奶消化物样品增加了 CAT mRNA 表达 (p < 0.05)，但对 NF-κB p65 和 IL-1β 的表达没有影响 (p > 0.05)。CAT mRNA 表达的增加表明胃上皮细胞利用乳脂肪酸进行能量产生。细胞对更高乳脂肪酸可用性的抗氧化反应可能与胃上皮炎症有关，但在与 IFN-γ外部接触的情况下，不会导致炎症增加。此外，常规或草饲来源并没有影响全脂奶对 NCI-N87 单层的影响。组合模型对牛奶脂肪含量的差异有反应，这表明它可用于研究食物在胃水平的作用。
