Redox homeostasis in stomach medium by foods: The Postprandial Oxidative Stress Index (POSI) for balancing nutrition and human health

Abstract

Red-meat lipid peroxidation in the stomach results in postprandial oxidative stress (POS) which is characterized by the generation of a variety of reactive cytotoxic aldehydes including malondialdehyde (MDA). MDA is absorbed in the blood system reacts with cell proteins to form adducts resulting in advanced lipid peroxidation end products (ALEs), producing dysfunctional proteins and cellular responses. The pathological consequences of ALEs tissue damage include inflammation and increased risk for many chronic diseases that are associated with a Western-type diet. In earlier studies we used the simulated gastric fluid (SGF) condition to show that the in vitro generation of MDA from red meat closely resembles that in human blood after consumption the same amount of meat. In vivo and in vitro MDA generations were similarly suppressed by polyphenol-rich beverages (red wine and coffee) consumed with the meal. The present study uses the in vitro SGF to assess the capacity of more than 50 foods of plant origin to suppress red meat peroxidation and formation of MDA. The results were calculated as reducing POS index (rPOSI) which represents the capacity in percent of 100 g of the food used to inhibit lipid peroxidation of 200 g red-meat a POSI enhancer (ePOSI). The index permitted to extrapolate the need of rPOSI from a food alone or in ensemble such Greek salad, to neutralize an ePOSI in stomach medium, (ePOS–rPOSI=0). The correlation between the rPOSI and polyphenols in the tested foods was R2=0.75. The Index was validated by comparison of the predicted rPOSI for a portion of Greek salad or red-wine to real inhibition of POS enhancers. The POS Index permit to better balancing nutrition for human health.

Intake of Oxidized Proteins and Amino Acids and Causative Oxidative Stress and Disease: Recent Scientific Evidences and Hypotheses

“…The ( in vivo ) oxidative stress occurred as a result of the intake of a pro‐oxidative diet is defined by Kanner et al. () as “postprandial oxidative stress.” The interconnection between all these terms is illustrated in Figure . Disappointingly, Kanner et al.…”

“…Furthermore, the ongoing oxidation of food components at stages during which such components eventually become tissue components leads to a reasonable deduction: the connection between "dietary oxidative stress" (including food and luminal oxidative stress) and "in vivo oxidative stress" (as understood in classic definitions) is definite as the former contribute to the latter in a straightforward manner. The (in vivo) oxidative stress occurred as a result of the intake of a pro-oxidative diet is defined by Kanner et al (2017) as "postprandial oxidative stress." The interconnection between all these terms is illustrated in Figure 1.…”

“…The interconnection between all these terms is illustrated in Figure 1. Disappointingly, Kanner et al (2017) identify such a diet as a "meal rich in lipids" though it is certainly known that proteinrich foods, such as lean red meat causes postprandial oxidative stress, inflammation, and increased risk to suffer serious diseases, as aforementioned (Jakobsen et al, 2017;Turner et al, 2017). It is assumed that oxidizing lipids play a major role in the pathogenesis of oxidative-driven pathologies while proteins are considered mere recipients of posttranslational changes.…”

Gut metabolites associated with pH and antioxidant capacity during in vitro colonic fermentation of Mexican corn products

“…FRAP values of IT decreased by 82.1% in the 12-to 48-hr fermentation period. This has led to the appearance of alternative analyses, such as ORAC (Rocchetti et al, 2018), FOX-2, and TBA assay (Kanner et al, 2017), which should be preferred for future studies. For FRAP, the values correspond to 40.45, 39.10, and 19.50 mmol TE for IT, BCT, and TCT, respectively, at 12 hr of fermentation.…”

“…Although the DPPH assay is still widely used for the assessment of antioxidant activity (An, Sun, Shen, & Ji, 2017;Wattananapakasem, Costabile, & Suwannaporn, 2018), the physiological relevance of this method has been questioned. This has led to the appearance of alternative analyses, such as ORAC (Rocchetti et al, 2018), FOX-2, and TBA assay (Kanner et al, 2017), which should be preferred for future studies. It should also be noted that the actual in vivo antioxidant capacity depends on several factors, including gut absorption, metabolism, bioavailability, and the presence of coantioxidants and transition metal ions (Kasote, Katyare, Hegde, & Bae, 2015).…”