PMID: 

Zhonghua Yu Fang Yi Xue Za Zhi. 2006 Sep ;40(5):314-8. PMID: 17166420

Abstract Title: 

[Effects of vitamin C on the inhibition of human leucocyte antigen class I (HLA-I) expression of human peripheral blood mononuclear cells induced by deoxynivalenol in vitro].

Abstract: 

OBJECTIVE: To explore the putative effects of Vitamin C (Vit C) on inhibition of human leucocyte antigen class I (HLA-I) expression of human peripheral blood mononuclear cells (HPBMCs) induced by deoxynivalenol (DON) in vitro.METHODS: The effects of Vit C on the changes of HLA-I expression of HPBMCs induced by DON in vitro were evaluated with cell culture, flow cytometry (FCM), Western blotting and immunocytochemical methods.RESULTS: FCM analysis showed that HLA-I expression of HPBMCs in DON treated cells was significantly lower than that in controls (FI 0.88 +/- 0.02 vs 1.00 +/- 0.03, P

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PMID: 

Br J Nutr. 2007 Jan ;97(1):19-26. PMID: 17217556

Abstract Title: 

Dose-dependent modulation of the T cell proteome by ascorbic acid.

Abstract: 

To investigate the hypothesis that the micronutrient ascorbic acid can modulate the functional genome, T cells (CCRF-HSB2) were treated with ascorbic acid (up to 150 microM) for up to 24 h. Protein expression changes were assessed by two-dimensional electrophoresis. Forty-one protein spots which showed greater than two-fold expression changes were subject to identification by matrix-assisted laser desorption ionisation time of flight MS. The confirmed protein identifications were clustered into five groups; proteins were associated with signalling, carbohydrate metabolism, apoptosis, transcription and immune function. The increased expression of phosphatidylinositol transfer protein (promotes intracellular signalling) within 5 min of ascorbic acid treatment was confirmed by Western blotting. Together, these observations suggest that ascorbic acid modulates the T cell proteome in a time- and dose-dependent manner and identify molecular targets for study following antioxidant supplementation in vivo.

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PMID: 

Med Sci Monit. 2007 Mar ;13(3):BR51-8. PMID: 17325628

Abstract Title: 

A novel vitamin C preparation enhances neurite formation and fibroblast adhesion and reduces xenobiotic-induced T-cell hyperactivation.

Abstract: 

BACKGROUND: Vitamin C (ascorbic acid, ascorbate) has been shown to enhance neurite outgrowth, promote fibroblast adhesion during wound healing, and reduce xenobiotic-induced leukocyte hyperactivity and inflammatory damage. In this study, a comparison was made between Ester-C and PureWay-C on these various cellular activities.MATERIAL/METHODS: PC12 cells were stimulated to form neurites with nerve growth factor, NIH 3T3 fibroblasts were seeded on fibronectin and H9 T-cells were stimulated to aggregate with the pyrethroid pesticide bifenthrin. The rate of neurite formation, fibroblast adhesion and T-cell homotypic aggregation was then measured in the absence and presence of various formulations of vitamin C including Ester-C and PureWay-CTM.RESULTS: With PureWay-C treatment, 12% of PC12 cells extended neurites within one hour of treatment and 45% of the cells extended neurites by hour nine. With Ester-C, 0% and 15% extended neurites at one and nine hours, respectively. NIH-3T3 fibroblast adhesion to fibronectin was enhanced by 4.7-fold with a 30 minute PureWay-CTM treatment while Ester-C increased fibroblast adhesion by only 1.5 fold. Further, PureWay-CTM reduced pesticide-mediated T-cell homotypic aggregation by 83% within 30 minutes of treatment while the reduction seen with Ester-C was only 33%.CONCLUSIONS: These data confirm the previous observations that vitamin C supplementation can promote neurite outgrowth, increase fibroblast adhesion and reduce xenobiotic induce immunocytes aggregation. More importantly, these data show that PureWay-C has a faster and greater beneficial effect on these parameters when compared to other vitamin C formulations.

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PMID: 

Neonatology. 2007 ;91(1):54-60. Epub 2006 Nov 10. PMID: 17344653

Abstract Title: 

Immunomodulatory effect of vitamin C on intracytoplasmic cytokine production in neonatal cord blood cells.

Abstract: 

BACKGROUND: Vitamin C (ascorbic acid) is an essential water-soluble antioxidant in cells and plasma. Besides metabolic functions, vitamin C is also known to contribute to immune homeostasis. Recently, it has been demonstrated that vitamin C has an inhibitory effect on the expression of pro-inflammatory cytokines such as interleukin (IL)-6 and tumor necrosis factor alpha (TNF-alpha) in adult whole blood cells in vitro. It has been postulated that vitamin C might be an interesting compound for modulation of an over-exuberant immune response, e.g., in patient cohorts susceptible for the development of systemic inflammatory response syndrome such as neonates. It was the aim of this study to investigate the modulatory effects of vitamin C on the production of inflammatory mediators in neonatal cord blood cells.METHODS: The intracytoplasmic production of pro-inflammatory cytokines in neonatal cord blood cells stimulated with lipopolysaccharide or phorbol 12-myristate 13-acetate/ionomycin was assessed by flow-cytometry.RESULTS: In contrast to our previous observations from adult whole blood cells, 20 mM vitamin C mildly stimulated the percentage of neonatal monocytes producing IL-6 after lipopolysaccharide stimulation (e.g., 11.3% increase compared to control, p = 0.005). In the presence of 20 mM vitamin C, even a stronger stimulatory effect was noted for the percentage of IL-8 (e.g., 46.7% increase, p

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PMID: 

Br J Nutr. 2007 Apr ;97(4):639-43. PMID: 17349075

Abstract Title: 

Orange juice vs vitamin C: effect on hydrogen peroxide-induced DNA damage in mononuclear blood cells.

Abstract: 

The intake of fruits rich in vitamin C seems to increase the antioxidant defence of the organism. However, it is still not clear whether vitamin C alone is responsible for this effect. The aim of the present investigation was to study the effect of the intake of a single portion of blood orange juice (BOJ, 300 ml, providing 150 mg vitamin C) on mononuclear blood cell (MNBC) DNA damage, compared with a drink supplemented with the same amount of vitamin C (C-drink) or sugars (S-drink). Seven young healthy subjects were randomised in a repeated-measures design in which they received each drink on different occasions, 2 weeks apart. Blood samples were collected at baseline, every hour for 8 h, and at 24 h after the intake of each drink. Vitamin C was analysed at each time point by HPLC, whereas H2O2-induced MNBC DNA damage was evaluated at 0, 3 and 24 h by means of the comet assay. Plasma vitamin C concentration increased similarly following BOJ or C-drink intake and was not affected by the S-drink. DNA damage significantly decreased 3 h after BOJ intake (about 18 %; P

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PMID: 

Mutat Res. 2008 Jan 8 ;649(1-2):71-8. Epub 2007 Aug 6. PMID: 17851119

Abstract Title: 

Modulation of gamma-ray-induced apoptosis in human peripheral blood leukocytes by famotidine and vitamin C.

Abstract: 

To study the radioprotective effects of vitamin C and famotidine against radiation-induced apoptosis in human peripheral blood leukocytes, peripheral blood was obtained from six healthy volunteers including three males and three females. Twelve microlitres of blood sample diluted in 1 ml complete RPMI-1640 medium was irradiated with various doses of gamma-rays (4, 8 and 12 Gy) in the presence or absence of various doses of vitamin C and famotidine. After 48 and 72 h incubation in a 37 degrees C CO(2) incubator, neutral comet assay was performed for all samples. At least 1000 cells were analyzed for each sample for presence of apoptosis. Data were statistically evaluated using Mann-Whitney non-parametric and ANOVA tests. Results show a significant increase in apoptosis induction following gamma-irradiation with a dose dependent manner compared to controls (p

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PMID: 

Br J Nutr. 2007 Oct ;98 Suppl 1:S29-35. PMID: 17922955

Abstract Title: 

Selected vitamins and trace elements support immune function by strengthening epithelial barriers and cellular and humoral immune responses.

Abstract: 

Adequate intakes of micronutrients are required for the immune system to function efficiently. Micronutrient deficiency suppresses immunity by affecting innate, T cell mediated and adaptive antibody responses, leading to dysregulation of the balanced host response. This situation increases susceptibility to infections, with increased morbidity and mortality. In turn, infections aggravate micronutrient deficiencies by reducing nutrient intake, increasing losses, and interfering with utilization by altering metabolic pathways. Insufficient intake of micronutrients occurs in people with eating disorders, in smokers (active and passive), in individuals with chronic alcohol abuse, in certain diseases, during pregnancy and lactation, and in the elderly. This paper summarises the roles of selected vitamins and trace elements in immune function. Micronutrients contribute to the body's natural defences on three levels by supporting physical barriers (skin/mucosa), cellular immunity and antibody production. Vitamins A, C, E and the trace element zinc assist in enhancing the skin barrier function. The vitamins A, B6, B12, C, D, E and folic acid and the trace elements iron, zinc, copper and selenium work in synergy to support the protective activities of the immune cells. Finally, all these micronutrients, with the exception of vitamin C and iron, are essential for antibody production. Overall, inadequate intake and status of these vitamins and trace elements may lead to suppressed immunity, which predisposes to infections and aggravates malnutrition. Therefore, supplementation with these selected micronutrients can support the body's natural defence system by enhancing all three levels of immunity.

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PMID: 

Circ J. 2008 Apr ;72(4):654-9. PMID: 18362440

Abstract Title: 

Vitamin C reversed malfunction of peripheral blood-derived mononuclear cells in smokers through antioxidant properties.

Abstract: 

BACKGROUND: Smoking impairs neovascularization, possibly, through the impaired function of peripheral blood-derived mononuclear cells (PB-MNCs). Thus, the mechanism of impaired function of PB-MNCs caused by chronic smoking was examined, and whether vitamin C reversed the malfunction of PB-MNCs in smokers was investigated.METHODS AND RESULTS: The cohort comprised 27 healthy male volunteers (16 smokers and 11 age-matched non-smokers). For evaluation of the colony-forming activity of PB-MNCs, the number of endothelial colony-forming units (e-CFUs) was counted in a culture assay. Migration activity of PB-MNCs was evaluated by the modified Boyden chamber method. In smokers, the number of e-CFUs was reduced to 56% and migratory activity of PB-MNCs to 40% compared with non-smokers (p

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PMID: 

Radiat Res. 2008 Apr ;169(4):384-96. PMID: 18363433

Abstract Title: 

Dietary antioxidants protect hematopoietic cells and improve animal survival after total-body irradiation.

Abstract: 

The purpose of this study was to determine whether a dietary supplement consisting of L-selenomethionine, vitamin C, vitamin E succinate, alpha-lipoic acid and N-acetyl cysteine could improve the survival of mice after total-body irradiation. Antioxidants significantly increased the 30-day survival of mice after exposure to a potentially lethal dose of X rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 h after 1 Gy and 8 Gy. Antioxidants were effective in preventing peripheral lymphopenia only after low-dose irradiation. Antioxidant supplementation was also associated with increased bone marrow cell counts after irradiation. Supplementation with antioxidants was associated with increased Bcl2 and decreased Bax, caspase 9 and TGF-beta1 mRNA expression in the bone marrow after irradiation. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow after sublethal or potentially lethal irradiation. Taken together, oral supplementation with antioxidants appears to be an effective approach for radioprotection of hematopoietic cells and improvement of animal survival, and modulation of apoptosis is implicated as a mechanism for the radioprotection of the hematopoietic system by antioxidants.

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PMID: 

J Sports Med Phys Fitness. 2008 Jun ;48(2):217-24. PMID: 18427418

Abstract Title: 

Effect of vitamin C supplementation on lipid peroxidation, muscle damage and inflammation after 30-min exercise at 75% VO2max.

Abstract: 

AIM: Hypothetically, supplementation with the antioxidant vitamins C could alleviate exercise-induced lipid peroxidation. The purpose of this study was to evaluate the effect of vitamin C supplementation on exercise-induced lipid peroxidation, muscle damage and inflammation.METHODS: Sixteen healthy untrained male volunteers participated in a 30-min exercise at 75% Vo2max. Subjects were randomly assigned to one of two groups: 1) placebo and 2) vitamin C (VC: 1 000 mg vitamin C). Blood samples were obtained prior to supplementation (baseline), 2 h after supplementation (immediately pre-exercise), post-exercise, 2 and 24 h after exercise. Plasma levels of VC, total antioxidant capacity (TAC), creatine kinase (CK), malondealdehyde (MDA), total leukocytes, neutrophils, lymphocytes, interleukin-6 (IL-6) and cortisol were measured.RESULTS: Plasma vitamin C concentrations increased significantly in the VC in response to supplementation and exercise (P

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