Assessment of inflammatory resilience in healthy subjects using dietary lipid and glucose challenges

Abstract

BackgroundResilience or the ability of our body to cope with daily-life challenges has been proposed as a new definition of health, with restoration of homeostasis as target resultant of various physiological stress responses. Challenge models may thus be a sensitive measure to study the body’s health. The objective of this study was to select a dietary challenge model for the assessment of inflammatory resilience. Meals are a challenge to metabolic homeostasis and are suggested to affect inflammatory pathways, yet data in literature are limited and inconsistent.MethodThe kinetic responses of three different dietary challenges and a water control challenge were assessed on various metabolic and inflammatory markers in 14 healthy males and females using a full cross-over study design. The dietary challenges included glucose (75 g glucose in 300 ml water), lipids (200 ml whipping cream) and a mix of glucose and lipids (same amounts as above), respectively. Blood samples were collected at baseline and at 0.5, 1, 2, 4, 6, 8 and 10 h after consumption of the treatment products. Inflammation (IFNγ, IL-1β, IL-6, IL-8, IL-10, IL-12p70, TNF-α CRP, ICAM-1, VCAM-1, SAA, E-selectin, P-selectin, thrombomodulin, leukocytes, neutrophils, lymphocytes) and clinical (e.g. glucose, insulin, triglycerides) markers as well as gene expression in blood cells and plasma oxylipin profiles were measured.ResultsAll three dietary challenges induced changes related to metabolic control such as increases in glucose and insulin after the glucose challenge and increases in triglycerides after the lipid challenge. In addition, differences between the challenges were observed for precursor oxylipins and some downstream metabolites including DiHETrE’s and HODE’s. However, none of the dietary challenges induced an acute inflammatory response, except for a modest increase in circulating leukocyte numbers after the glucose and mix challenges. Furthermore, subtle, yet statistically significant increases in vascular inflammatory markers (sICAM-1 and sVCAM-1) were found after the mix challenge, when compared to the water control challenge.ConclusionsThis study shows that dietary glucose and lipid challenges did not induce a strong acute inflammatory response in healthy subjects, as quantified by an accurate and broad panel of parameters.

Multi-parameter comparison of a standardized mixed meal tolerance test in healthy and type 2 diabetic subjects: the PhenFlex challenge

“…Also, most markers related to oxidative stress represented by uric acid, vitamin E, ribose, erythronic acid, and mannose showed a significant time response as well as metabolic flexibility (RQ). These processes are known to be augmented by a mixed meal challenge as compared to single macronutrient challenges such as OGTT and oral lipid tolerance test (OLTT) [3,8]. Therefore, we conclude that PFT modulated phenotypic flexibility as expected in healthy individuals.…”

“…The use of emerging technologies like metabolic profiling and targeted proteomics in metabolic tolerance tests has allowed the development of a new generation of biomarkers [5] by the simultaneous quantification of multiple processes [3,[6][7][8][9][10][11]. The response to challenges may be used to derive biomarkers for maintenance of physiological function and ultimately as indicator for prevention of (metabolic) diseases.…”

Design and implementation of a cross-sectional nutritional phenotyping study in healthy US adults

“…The strengths of this study include the multiple dietary data collection tools used for assessment of dietary intake, the broad range of outcomes to be included in the phenotypic analysis, and a study design that minimizes losses to follow-up. The similarity of the challenge meal formula to one previously designed by European Nutrigenomics Organization [18] also provides the potential for comparison with phenotypic flexibility data in a US population to similar data collected in European populations. Limitations of this study include a lack of control group for comparison of the postprandial changes in response to the challenge meal and the unknown contamination of particular measurements that may result from performing other study tasks during the same day (e.g.…”

“…A mixed macronutrient liquid challenge meal patterned after a similar meal developed by the European Nutrigenomics Organization [18] contains the main ingredients: palm oil, sucrose, and pasteurized liquid egg white. Xanthan gum and cellulose gum standardized with maltodextrin are added as emulsifying agents; vanilla and almond extracts and artificial butter flavoring are added to improve palatability.…”

Quantifying phenotypic flexibility as the response to a high‐fat challenge test in different states of metabolic health

“…Acute high-fat tolerance tests (with or without additional glucose and protein) have also been applied to evaluate postprandial responses of multiple processes, but not in a standardized manner. High-fat challenge tests are used to study lipid metabolism and metabolic flexibility, but also induce low-grade postprandial inflammation and endothelial dysfunction (4)(5)(6)(7).…”