Abstract 16807: The Association Between Dietary Factors and the Distribution of Monocyte Subsets: A Systematic Review

Abstract

Introduction: Three subsets of monocytes have been identified in humans (i.e. classical, intermediate and non-classical), which have been proposed to differently contribute to the pathogenesis of atherosclerosis, a major cause of cardiovascular disease (CVD). Previous studies implicate a shift in the distribution of monocyte subsets from classical (CM) to intermediate (IM) and non-classical monocytes (NCM) in individuals with cardiometabolic disorders, which is hypothesized to contribute to CVD development. The risk of cardiometabolic disease is strongly associated with dietary habits. Thus, the aim of the current systematic review was to evaluate the association between dietary factors and the distribution of monocyte subsets. Methods: Articles were systematically searched in CINAHL, Cochrane Central Register of Controlled Trials, and PubMed until May 2020. A total of 2496 articles were independently screened by 2 reviewers. Eligible study subjects were adults > 18 years old. Eligible studies were cross-sectional, cohort, within-subject design studies and randomized-controlled trials that examine the effect of dietary factors on monocyte subset distribution. A total of 12 studies were included in this review. Results: A single high fat meal challenge increased the number and percentage of NCM (n=1) and increased the number and percentage of CM (n=1) in healthy subjects. Consuming a high-salt diet for a week increased the number and percentage of IM in healthy subjects, whereas these changes were reversed after switching to a low-salt diet (n=2). EPA+DHA supplementation (4 g/day) for 2 weeks decreased the number and percentage of IM in patients with hypertriglyceridemia (n=2). Lastly, one cross-sectional study showed that the number and percentage of IM was lower in patients with CVD who consumed a high quality diet compared to low quality diet. Conclusions: Dietary factors may influence the distribution of monocyte subsets. However, the role of diet-induced changes in the distribution of monocytes on atherosclerosis risk remains unknown. Additional mechanistic studies are needed to understand the relationship between dietary factors, changes in the distribution of monocyte subsets and atherosclerotic risk.