Ascorbic acid inhibits replication and infectivity of avian RNA tumor virus.

Bissell, Mina J.; Hatié, Carroll; Farson, Deborah; Schwarz, Richard I.; Soo, Whaijen

doi:10.1073/pnas.77.5.2711

Cited by 40 publications

(18 citation statements)

References 24 publications

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“…Ascorbate also has been found to have no effect on total collagen synthesis in human synovial cells, but this may be due to the much shorter duration oftreatment used (29). In primary avian tendon cells, however, collagen synthesis was stimulated by ascorbate (15) although a later report from the same laboratory contradicted the earlier observation (30). Furthermore, it was difficult to be sure if this was a primary effect or was secondary to changes in cell density which has been found to exert a significant influence on collagen synthesis relative to noncollagen protein synthesis (17).…”

Section: Methodscontrasting

confidence: 47%

Regulation of collagen synthesis by ascorbic acid.

Murad¹,

Grove²,

Lindberg³

et al. 1981

Proc. Natl. Acad. Sci. U.S.A.

396

221

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After prolonged exposure to ascorbate, collagen synthesis in cultured human skin fibroblasts increased approximately 8-fold with no significant change in synthesis ofnoncollagen protein. This effect of ascorbate appears to be unrelated to its cofactor function in collagen hydroxylation. The collagenous protein secreted in the absence of added ascorbate was normal in hydroxylysine but was mildly deficient in hydroxyproline. In parallel experiments, lysine hydroxylase (peptidyllysine, 2-oxoglutarate:oxygen 5-oxidoreductase, EC 1.14.11.4) activity increased 3-fold in response to ascorbate administration whereas proline hydroxylase (prolyl-glycyl-peptide, 2-oxoglutarate:oxygen oxidoreductase, EC 1.14.11.2) activity decreased considerably. These results suggest that collagen polypeptide synthesis, posttranslational hydroxylations, and activities of the two bydroxylases are independently regulated by ascorbate.Ascorbic acid is essential for normal collagen formation (1-3) by virtue ofthe fact that it is a required component in the synthesis of hydroxyproline and hydroxylysine in collagen (4). Hydroxyproline serves to stabilize the collagen triple helix (5, 6); its absence results in structurally unstable collagen (7, 8) which is not secreted from cells at a normal rate (9). Hydroxylysine is necessary for formation of the intermolecular crosslinks in collagen (10). In addition, specific carbohydrate residues are linked glycosidically to collagen through hydroxylysine, a process that may be important in the regulation of crosslink formation (11).It is generally believed that ascorbate modulates collagen production through its effect on prolyl hydroxylation (12). There have been indications, however, that ascorbate may have an additional role in collagen biosynthesis (13-16). Notable are the early studies by Jeffrey and Martin (13) who observed a substantial increase in the size of chicken long bones cultured in the presence of ascorbate, concomitant with an increase in the incorporation of proline into peptidyl hydroxyproline.In this study we have examined the long-term effect of ascorbate on collagen production by cultured human skin fibroblasts. The influence ofascorbate on prolyl hydroxylase (prolylglycyl-peptide, 2-oxoglutarate:oxygen oxidoreductase, EC 1.14.11.2) and lysyl hydroxylase (peptidyllysine, 2 oxoglutarate:oxygen 5-oxidoreductase, EC 1.14.11.4) levels was also examined simultaneously to understand better the interrelationship of collagen synthesis and posttranslational hydroxylation. The data indicate that ascorbate increases collagen synthesis by acting at a level other than hydroxylation. MATERIALS AND METHODSHuman skin fibroblasts from a normal 3-day-old boy (GM 970) were obtained from the Institute for Medical Research (Camden, NJ) and grown to confluent density in Dulbecco's modified Eagle's medium buffered with 24 mM sodium bicarbonate and 25 mM Hepes and supplemented with 20% fetal calf serum (GIBCO) which had been inactivated for 30 min at 560C. Cultures were growth arrested for 90 hr in ...

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Section: Methodscontrasting

confidence: 47%

Regulation of collagen synthesis by ascorbic acid.

Murad¹,

Grove²,

Lindberg³

et al. 1981

Proc. Natl. Acad. Sci. U.S.A.

396

221

View full text Add to dashboard Cite

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“…In particular, Bissell et al (1980) found similar suppression of viral replication in cell culture with L-and D-ascorbic acid. Accordingly, in the current state of knowledge it seems reasonable to combine the Clegg & Macdonald (1975) L-and D-isomer groups.…”

Section: Reply By Hemilämentioning

confidence: 53%

Nutrition Discussion Forum

Boucher¹

1998

Br J Nutr

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“…The half-life of AsA in the medium is less than 8 hr (16). Therefore, AsA was added repeatedly to the culture at 12-hr intervals, and its effect on antibody production was studied (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…We found that AA-2G stimulated PWM (17) and SAC (18)-induced antibody production remark ably, whereas AsA had no stimulating effect by a single addition. AsA in the medium rapidly decomposed with a very short half-life (1-8 hr) (16), but the high stability of AA-2G in neutral solution (6, 9) makes it more useful than AsA in a long-term cell culture. Moreover, we confirmed that AA-2G had no cytotoxicity in PBLs, but AsA showed cytotoxicity at concentrations higher than 0.25 mM.…”

Section: Discussionmentioning

confidence: 99%

Enhancement by Ascorbic Acid 2-Glucoside or Repeated Additions of Ascorbate of Mitogen-Induced IgM and IgG Productions by Human Peripheral Blood Lymphocytes

Tanaka

Muto

Gohda

et al. 1994

Japanese Journal of Pharmacology

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ABSTRACT-In this study, the effect of ascorbic acid 2-glucoside (AA-2G), a stable derivative of ascorbic acid (AsA), or repeated additions of ascorbate on antibody productions by human peripheral blood lym phocytes (PBLs) was examined, and the physiological function of AsA was evaluated. When human PBLs were stimulated with Staphylococcus aureus Cowan I or pokeweed mitogen, AA-2G remarkably increased the numbers of IgM and IgG-secreting cells which were detected by enzyme-linked immunospot assay. Although a single addition of ascorbate was without effect, the effect of AA-2G was remarkably inhibited by the addition of castanospermine, an a-glucosidase inhibitor; and moreover, repeated additions of AsA to the culture medium during the culture period enhanced the response to the same level as did a single addi tion of AA-2G. These results indicate that AsA has the ability to stimulate the immunoglobulin productions by AA-2G. The phytohemagglutinin-induced proliferative response of PBLs was also stimulated by AA 2G. The intracellular AsA content in PBLs cultured with AA-2G was maintained at relatively high levels dur ing the culture period, whereas the content with a single dose of AsA reached nearly zero by the end of the experiment. These in vitro findings suggest that AA-2G and AsA function as potent immunostimulators of antibody production in humans and that the intracellular AsA content is a key parameter for establishing the immune response of PBLs.

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Ascorbic acid inhibits replication and infectivity of avian RNA tumor virus.

Cited by 40 publications

References 24 publications

Regulation of collagen synthesis by ascorbic acid.

Regulation of collagen synthesis by ascorbic acid.

Nutrition Discussion Forum

Enhancement by Ascorbic Acid 2-Glucoside or Repeated Additions of Ascorbate of Mitogen-Induced IgM and IgG Productions by Human Peripheral Blood Lymphocytes

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