Author(s): Anitra CC, Silvia M
Vitamin C is an essential micronutrient for humans, with pleiotropic functions related to its ability to donate electrons. It is a potent antioxidant and a cofactor for a family of biosynthetic and gene regulatory enzymes. Vitamin C contributes to immune defense by supporting various cellular functions of both the innate and adaptive immune system. Vitamin C supports epithelial barrier function against pathogens and promotes the oxidant scavenging activity of the skin, thereby potentially protecting against environmental oxidative stress. Vitamin C accumulates in phagocytic cells, such as neutrophils, and can enhance chemotaxis, phagocytosis, generation of reactive oxygen species, and ultimately microbial killing. It is also needed for apoptosis and clearance of the spent neutrophils from sites of infection by macrophages, thereby decreasing necrosis/NETosis and potential tissue damage. The role of vitamin C in lymphocytes is less clear, but it has been shown to enhance differentiation and proliferation of B- and T-cells, likely due to its gene regulating effects. Vitamin C deficiency results in impaired immunity and higher susceptibility to infections. In turn, infections significantly impact on vitamin C levels due to enhanced inflammation and metabolic requirements. Furthermore, supplementation with vitamin C appears to be able to both prevent and treat respiratory and systemic infections. Prophylactic prevention of infection requires dietary vitamin C intakes that provide at least adequate, if not saturating plasma levels (i.e., 100–200 mg/day), which optimize cell and tissue levels. In contrast, treatment of established infections requires significantly higher (gram) doses of the vitamin to compensate for the increased inflammatory response and metabolic demand.
Referred From: http://www.mdpi.com/2072-6643/9/11/1211
Author(s): Yoshida M, Takashima Y, Inoue M, Iwasaki M, Otani T, et al.
Author(s): Aguirre R, May JM
Author(s): Harding AH, Wareham NJ, Bingham SA, Khaw K, Luben R, et al.
Author(s): Godic A, Poljšak B, Adamic M, Dahmane R
Author(s): Tyrrell RM
Author(s): Chen L, Hu JY, Wang SQ
Author(s): Mikirova NA, Casciari JJ, Riordan NH
Author(s): Casciari JJ, Riordan NH, Schmidt TL, Meng XL, Jackson JA, et al.
Author(s): Juan Du, Joseph J. Cullena, Garry R. Buettner
Author(s): Murray JC, Burch JA, Streilein RD, Lannacchione MA, Hall RP, et al.
Author(s): Mohammed BM, Fisher BJ, Kraskauskas D, War S, Wayne JS, et al.
Author(s): Desneves KJ, Todorovic BE, Cassar A, Crowe TC
Author(s): Blass SC, Goost H, Tolba RH, Stoffel-Wagner B, Kabir K, et al.
Author(s): Oresajo C, Stephens T, Hino PD, Law RM, Yatskayer M, et al.
Author(s): Mohammed B, Fisher BJ, Kraskauskas D, War S, Wayne JS, et al.
Author(s): Savini I, Catani MV, Rossi A, Duranti G, Melino G, et al.
Author(s): Uchida Y, Behne M, Quiec D, Elias PM, Holleran WM
Author(s): Sram RJ, Binkova B, Rossner P
Author(s): Pozzer A, Zimmermann P, Doering U, Van Aardenne J, Tost H, et al.
Author(s): Bruno RS, Leonard SW, Atkinson J, Montine TJ, Ramakrishnan R, et al.
Author(s): Lin FH, Lin JY, Gupta RD, Tournas JA, Burch JA, et al.
Author(s): Huijskens MJ, Walczak M, Koller N, Briede JJ, Senden-Gijsbers BL, et al.
Author(s): Huijskens MJ, Walczak M, Sarkar S, Atrafi F, Senden-Gijsbers BL, et al.
Author(s): Boura P, Tsapas G, Papadopoulou A, Magoula I, Kountouras G
Author(s): Matsui MS, Hsia A, Miller JD, Hanneman K, Scull H, et al.
Author(s): Hagel AF, Layritz CM, Hagel WH, Hagel HJ, Hagel E, et al.