title: Metabolic Effects of Inflammation on Vitamin A and Carotenoids in Humans and Animal Models.
abstract: The association between inflammation and vitamin A (VA) metabolism and status assessment has been documented in multiple studies with animals and humans. The relation between inflammation and carotenoid status is less clear. Nonetheless, it is well known that carotenoids are associated with certain health benefits. Understanding these relations is key to improving health outcomes and mortality risk in infants and young children. Hyporetinolemia, i.e., low serum retinol concentrations, occurs during inflammation, and this can lead to the misdiagnosis of VA deficiency. On the other hand, inflammation causes impaired VA absorption and urinary losses that can precipitate VA deficiency in at-risk groups of children. Many epidemiologic studies have suggested that high dietary carotenoid intake and elevated plasma concentrations are correlated with a decreased risk of several chronic diseases; however, large-scale carotenoid supplementation trials have been unable to confirm the health benefits and in some cases resulted in controversial results. However, it has been documented that dietary carotenoids and retinoids play important roles in innate and acquired immunity and in the body's response to inflammation. Although animal models have been useful in investigating retinoid effects on developmental immunity, it is more challenging to tease out the effects of carotenoids because of differences in the absorption, kinetics, and metabolism between humans and animal models. The current understanding of the relations between inflammation and retinoid and carotenoid metabolism and status are the topics of this review.
authors.affiliation: Texas Tech Health Sciences Center El Paso, El Paso, TX.
authors.forename: Lewis P
authors.initials: LP
authors.lastname: Rubin
authors.affiliation: Pennsylvannia State University, State College, PA.
authors.forename: A Catharine
authors.initials: AC
authors.lastname: Ross
authors.affiliation: USDA Western Human Nutrition Research Center, Davis, CA.
authors.forename: Charles B
authors.initials: CB
authors.lastname: Stephensen
authors.affiliation: Luxembourg Institute of Health, Population Health Department, Strassen, Luxembourg; and.
authors.forename: Torsten
authors.initials: T
authors.lastname: Bohn
authors.affiliation: Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI sherry@nutrisci.wisc.edu.
authors.forename: Sherry A
authors.initials: SA
authors.lastname: Tanumihardjo
mesh_terms: D000818:Animals; D002338:Carotenoids / Q000008:administration & dosage / Q000097:blood*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000150:complications; D014801:Vitamin A / Q000008:administration & dosage / Q000097:blood*; D014802:Vitamin A Deficiency / Q000097:blood / Q000150:complications / Q000175:diagnosis
chemical_list: D014801:Vitamin A; D002338:Carotenoids
keywords: biomarkers; cytokines; infection; retinol; retinol-binding protein; sequestration; urinary loss