title: Impact of a cholesterol membrane transporter's inhibition on vitamin D absorption: A double-blind randomized placebo-controlled study.
abstract: Oral supplements are important to prevent and treat vitamin D deficiency. Despite the growing number of prescriptions, vitamin D's absorptive mechanisms are not clearly elucidated. By evaluating the effect of ezetimibe on vitamin D absorption, we aim to determine if the cholesterol transporter Niemann-Pick C1-Like 1 transporter contributes to it. This randomized, double-blind, placebo-controlled trial (ClinicalTrials.govNCT02234544) was developed in a South Brazilian University Hospital. Fifty-one medical students were randomized to ezetimibe 10mg/day or placebo for 5 days. On the fifth and 19th days, blood samples for 25-hydroxycholecalciferol (25OHD), parathyroid hormone (PTH), calcium, and albumin were collected. After the first blood sample collection, all participants received a single oral 50,000 IU cholecalciferol dose during a 15 g-fat meal. Serum 25OHD levels were measured by the immunoassay Diasorin Liaison®. Measurements were compared in a general linear model adjusted for multiple comparisons by the Bonferroni test. Before cholecalciferol administration, 25OHD was <30 ng/mL and <20 ng/mL, respectively, in all and in 82.3% of the participants. Fourteen days after a single 50,000 IU oral dose of cholecalciferol, mean (SD) changes in serum 25OHD were similar in both groups, after adjustment to BMI and 25OHD levels before cholecalciferol administration (p=0.26): 8.7 (3.7) ng/mL in the ezetimibe group, versus 10.0 (3.8) ng/mL in the placebo group. Mean serum 25OHD, PTH, calcium and albumin levels remained similar in both groups. We conclude that ezetimibe had no effect on the mean change in serum 25OHD after a single oral dose of cholecalciferol, in these healthy and young adults.
authors.affiliation: Postgraduation Program in Medicine, Medical Science, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Mariana Costa
authors.initials: MC
authors.lastname: Silva
authors.affiliation: Postgraduation Program in Medicine, Medical Science, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil; Internal Medicine Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Gustavo Adolpho Moreira
authors.initials: GAM
authors.lastname: Faulhauber
authors.affiliation: Internal Medicine Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Érica Neves
authors.initials: ÉN
authors.lastname: Leite
authors.affiliation: Internal Medicine Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Kamila Ramborger
authors.initials: KR
authors.lastname: Goulart
authors.affiliation: Internal Medicine Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Jorge Mario Ahumada
authors.initials: JMA
authors.lastname: Ramirez
authors.affiliation: Internal Medicine Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Fernanda Mariani
authors.initials: FM
authors.lastname: Cocolichio
authors.affiliation: Postgraduation Program in Medicine, Medical Science, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil; Internal Medicine Division, Hospital de Clinicas de Porto Alegre, Porto Alegre, RS, Brazil. Electronic address: taniafurlanetto@gmail.com.
authors.forename: Tania Weber
authors.initials: TW
authors.lastname: Furlanetto
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000418:Albumins / Q000737:chemistry; D000924:Anticholesteremic Agents / Q000737:chemistry; D015992:Body Mass Index; D001938:Brazil; D002112:Calcifediol / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics*; D002118:Calcium / Q000097:blood; D002784:Cholesterol / Q000378:metabolism*; D019587:Dietary Supplements; D004311:Double-Blind Method; D000069438:Ezetimibe / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007118:Immunoassay; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000097:blood; D014807:Vitamin D / Q000737:chemistry / Q000493:pharmacokinetics*; D014808:Vitamin D Deficiency / Q000188:drug therapy*; D055815:Young Adult
chemical_list: D000418:Albumins; D000924:Anticholesteremic Agents; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; C410800:NPC1L1 protein, human; D010281:Parathyroid Hormone; D014807:Vitamin D; D002784:Cholesterol; D000069438:Ezetimibe; D002112:Calcifediol; D002118:Calcium
keywords: 25-Hydroxycholecalciferol; Absorption; Ezetimibe; Membrane transport proteins; Vitamin D