β-Carotene, α-tocopherol and ascorbic acid: differential profile of antioxidant, inflammatory status and regulation of gene expression in human mononuclear cells of diabetic donors.

Background: Diabetic patients are exposed to increased oxidative stress due to several mechanisms, mainly hyperglycaemia. Pathological processes, such as those in type 1 diabetes, include diminished activity of the antioxidant defense system(s) or excessive oxidative generation resulting in an oxidative/antioxidant imbalance and development of oxidative stress.

Methods: The purpose of this study was to evaluate the production of reactive oxygen species (ROS) (chemiluminescence) and reduction capacity (MTT dye reduction), the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits, superoxide dismutase and catalase using quantitative reverse-transcriptase polymerase chain reaction, and the levels of cytokines [interleukin (IL)-6, tumour necrosis factor-α, IL-8, IL-10 and IL-4] by sandwich enzyme-linked immunosorbent assay in mononuclear cells from non-diabetic and diabetic donors treated with a vitamin complex (ascorbic acid, β-carotene and α-tocopherol) in two different concentrations ([A] = ascorbic acid = 0.

High doses of in vitro beta-carotene, alpha-tocopherol and ascorbic acid induce oxidative stress and secretion of IL-6 in peripheral blood mononuclear cells from healthy donors.

Background: Oxidative stress represents an imbalance between the production and manifestation of reactive oxygen species (ROS) and a biological system's ability to readily detoxify the reactive intermediates or repair the resulting damage. Our objective was to verify the existence of an in vitro dual effect of alpha-tocopherol, beta-carotene and ascorbic acid in peripheral blood mononuclear cells (PBMNC) of healthy donors and the inflammatory capacity by IL-6 production.

Methods: PBMNC were incubated with two concentrations of vitamin complex: [A] = Ascorbic Acid = 0.

Ascorbic acid, alpha-tocopherol, and beta-carotene reduce oxidative stress and proinflammatory cytokines in mononuclear cells of Alzheimer's disease patients.

Objectives: The in vitro effect of a vitamin complex in generating and reducing oxidative species in peripheral blood mononuclear cells (PBMNC) and plasma of patients with Alzheimer's disease (AD) and healthy subjects (HS) was evaluated.

Methods: Two concentrations of a vitamin complex ([A] and [20A]) with ascorbic acid, alpha-tocopherol, and beta-carotene were incubated with either mononuclear cells or plasma. The generation of oxidizing species was measured in a luminol-dependent chemiluminescence assay and the reducing response by the MTT dye reduction assay.

Role PKA and p38 MAPK on ROS production in neutrophil age-related: Lack of IL-10 effect in older subjects.

Background: There is a large increase in the number of elderly people in modern societies. This demographic phenomenon has been paralleled by an epidemic of chronic diseases and inflammatory processes usually associated with advanced age.

Objective: We studied the role of protein kinase A (PKA), protein kinase B (Akt/PKB) and p38 mitogen-activated protein kinase (p38 MAPK) signaling pathways in ROS produced by neutrophils induced by pro-interferon-gamma (IFN-gamma) or anti-inflammatory interleukin 10 (IL-10) cytokines age-related.