Study title
Ex vivo inflammatory challenge of PBMNC from vitamin C supplemented healthy subjects
Template
Intervention/Observation study
title
Ex vivo inflammatory challenge of PBMNC from vitamin C supplemented healthy subjects
description
In order to study the effects of vitamin C supplementation on gene expression and compare its action between physiological and inflammatory conditions, a pilot study was set up utilizing microarray and qPCR technologies. Five healthy volunteers were supplemented with 1 g vitamin C (Redoxon) per day for five consecutive days. Peripheral blood mononuclear cells (PBMNC) were isolated before and just after the last supplementation, and RNA was isolated for the Affymetrix gene 1.0 ST chip analysis. PBMNC were also, ex vivo, treated with LPS, and gene expression was quantified by means of a ‘‘Human NFkB Signaling’’ qPCR array.
startDate
2011-03-21 00:00:00.0
Study type
Human Intervention
Principle Investigator
Raffaella Canali
Primary endpoint
Transcriptome
Objectives
To study the effects of vitamin C supplementation on gene expression and compare its action between physiological and inflammatory conditions.
Central conclusion
This study suggests that vitamin C supplementation in healthy subjects,
not selected according to a specific genetic profile, consuming an adequate amount of vitamin C, and having a satisfactory vitamin C plasma concentration at the baseline,
does not result in a significant modification of gene expression profile. Under this satisfactory micronutrient status, supplementation of vitamin C is ‘‘buffered’’ within a homeostatic physiological equilibrium. Differently, following
a second ‘‘hit’’ constituted of an inflammatory stimulus such as LPS, able to trigger a critical burst to the normal physiological state, the higher availability of
ascorbic acid emerges, and results in a significant modulation
of cell response.
Main health-related outcome
The effects of vitamin C supplementation on gene expression and compare its action between physiological and inflammatory conditions
Exclusion criteria
(1) no history of chronic disease, (2) no antibiotic or supplemental vitamin or mineral use for 4 weeks before the beginning of the study, (3) nonsmoking, (4) low physical activity, and (5) no drugs or nonsteroidal
Inclusion criteria
In good health as determined by a medical history questionnaire and clinical laboratory tests
Institute
CREA-NUT, Centro di ricerca per gli alimenti e la nutrizione - Roma
Country (for multicentre study overall PI)
Italy
Funding body
Bayer Consumer Care AG, Basel, Switzerland
Ethical approval number
The study protocol was approved by the internal ethical committee
Study design
Before and after
Diet short codes and descriptions
Type of controls
Untreated cells
Number of factors (for factorial designs only)
1
Total number of arms (Give number of distinct treatments in study)
1
Explanatory text (Give a textual account of the overall design leading to the total number of groups) or provide the study protocol.
Five healthy volunteers were supplemented with 1 g vitamin C (Redoxon) per day for five consecutive days. PBMNC were isolated at T=0 (fasting condition), and at day 5. RNA was isolated for Affymetrix gene 1.0 ST chip analysis. PBMNC were also treated with LPS ex vivo, and gene expression was quantified by means of a Human NFkB Signaling qPCR array.
Treatments (Number and types of foods, drugs or other treatments compared)
Subjects were instructed to maintain their usual habits (diet and physical activity) during the 5 days of Vitamin C supplementation. The subjects were asked to abstain from eating vegetables, fruits, and drinking alcohol the evening before the day of blood withdrawals. Subjects were asked to assume one tablet of Redoxon (Bayer) a day (containing 1 g of ascorbate), for 5 days.
Number of volunteers screened N(M:xx, F: xx)
10(M:6, F:4)
Number of volunteers enrolled N(M:xx, F: xx)
5(M:3, F:2)
Number of subjects (Male; Female)
5(M:3, F:2)
Start of recruitment (Start year or date)
2011-01-03 00:00:00.0
End of recruitment (End year or date)
2011-03-31 00:00:00.0
