scholarly journals The Genotoxicity of Vitamin C in vitro

2008 ◽  
Vol 8 (2) ◽  
pp. 141-146 ◽  
Author(s):  
Hilada Nefić
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Chromosome Segregation ◽  
Human Lymphocytes ◽  
Genotoxic Effects ◽  
Multipolar Spindles ◽  
Index Value ◽  
Chromosome Bridges ◽  
Spindle Function

The genotoxic effects of Vitamin C (ascorbic acid) on human lymphocytes in vitro were estimated by analyzing and identifying various chromosome abnormalities, in relation to the concentration of Vitamin C. Testing concentrations of Vitamin C induced different aberrations including the impairment of spindle function. The spindle disturbances can result in mitotic arrest, multipolar spindles and multipolar segregation, errors in chromosome segregation, formation of chromosome bridges and chromosome laggards. The most frequent irregularities were found in anaphase and telophase. A certain number of lymphocytes were arrested at anaphase or telophase (in colchicine-untreated cultures of human lymphocytes). Testing concentrations of ascorbic acid did not induce a significant increase in the number of aneuploid mitoses and were not clastogenic except at the highest concentration (1,000 μg/ml) in colchicine-treated cultures, and in colchicine-untreated cultures of human lymphocytes the pulverization of chromosome was observed. Vitamin C changed the mitotic index value of lymphocytes notably at the higher concentrations (250, 500 and 1,000 μg/ml).

Decreased Platelet Vitamin C in Diabetes Mellitus; Possible Role in Peraggregatoon

1979 ◽  
Author(s):  
K.E. Sarji ◽  
J. Gonzalez ◽  
H. Hempling ◽  
J.A. Colwell
Keyword(s):  
Ascorbic Acid ◽  
Arachidonic Acid ◽  
Platelet Aggregation ◽  
Vitamin C ◽  
Platelet Rich Plasma ◽  
Solution Ph ◽  
Dose Dependent Fashion ◽  
Insulin Dependent Diabetic ◽  
Induced Aggregation

To determine whether Vitamin C might relate to the increased platelet sensitivity in the diabetic, we have measured levels of platelet Vitamin C and studied the effects of Vitamin C on platelet aggregation. Ascorbic acid levels in washed platelets from diabetics were significantly lower than from normals (4s.2±3 μg/1010 platelets vs. 2s.s±2 μg/1010 platelets, p<.001). The effects of ascorbic acid on platelet aggregation in vitro were studied by adding ascorbic acid in buffered solution (pH 7.35) prior to-aggregating agents. Ascorbic acid in platelet-rich plasma consistently inhibited platelet aggregation with threshold concentrations of ADP, epinephrine, and collagen. With washed platelets, ascorbic acid inhibited arachidonic, acid-induced aggregation. When platelets were incubated at 37°C for 10 minutes with varying concentrations of ascorbic acid, rewashed, and aggregation with arachidonic acid tested, aggregation was inhibited in a linear dose-dependent fashion. Oral ingestion of ascorbic acid (2 gm/day) for seven days by normal non-smoking males produced a marked inhibition of aggregation. In a similar study, platelets from an insulin-dependent diabetic showed no change in aggregation. These results suggest that platelet levels of ascorbic acid may relate to the hyperaggregat ion of platelets from diabetics.

Genotoxic Effects of Amplitude-Modulated Microwaves on Human Lymphocytes Exposed in Vitro under Controlled Conditions

1995 ◽  
Vol 14 (3) ◽  
pp. 157-164 ◽  
Author(s):  
G. D'ambrosio ◽  
M. B. Lioi ◽  
R. Massa ◽  
M. R. Scarfi ◽  
O. Zeni
Keyword(s):  
Human Lymphocytes ◽  
Genotoxic Effects ◽  
Controlled Conditions

Dietary regulation of intestinal ascorbate uptake in guinea pigs

1991 ◽  
Vol 260 (1) ◽  
pp. G108-G118 ◽  
Author(s):  
W. H. Karasov ◽  
B. W. Darken ◽  
M. C. Bottum
Keyword(s):  
Ascorbic Acid ◽  
Vitamin C ◽  
Brush Border ◽  
Guinea Pigs ◽  
Dietary Regulation ◽  
Intestinal Brush Border ◽  
Pregnancy And Lactation ◽  
Human Adults ◽  
Ascorbate Uptake

We measured ascorbic acid (AA) uptake across the intestinal brush border in vitro in intact tissue from guinea pigs fed maintenance AA (200 mg/kg diet) or made hypervitaminotic (5,000 mg/kg diet) or hypovitaminotic (chronically and acutely). Total uptake per centimeter ileum was 25-50% lower in hypervitaminotic juvenile, adult male, and lactating guinea pigs compared with their respective controls, whereas carrier-mediated D-glucose uptake and Na(+)-independent AA uptake were similar. High dietary ascorbate specifically reduced the Vmax for carrier-mediated AA uptake. Hypovitaminosis had no significant effect on uptake of AA or other solutes. We performed diet-switching experiments (high-AA diet to maintenance diet) with young and adult guinea pigs to determine the reversibility of the downregulation. In adult guinea pigs, the downregulation of AA uptake was reversible within 7 days. In the young of mothers fed high AA during pregnancy and lactation, and which fed on high AA for 14 days after weaning, the downregulation was reversible within 14 days. Thus regulation of AA uptake is reversible and therefore probably does not play a significant role in the development of vitamin C dependency in human adults, or their young, after ingestion of megadoses of ascorbic acid.

Cytotoxic and genotoxic effects of paraquat in Hordeum vulgare and human lymphocytes in vitro

2009 ◽  
Vol 25 (3) ◽  
pp. 294-303 ◽  
Author(s):  
Gabriele Jovtchev ◽  
Svetla Gateva ◽  
Mila Stergios ◽  
Stanislava Kulekova
Keyword(s):  
Hordeum Vulgare ◽  
Human Lymphocytes ◽  
Genotoxic Effects

A study on the genotoxic effects of 8-Cl-cAMP on human lymphocytes in vitro

2008 ◽  
Vol 44 (5) ◽  
pp. 546-552
Author(s):  
V. Bajić ◽  
N. Djelić ◽  
B. Spremo-Potparević ◽  
L. Živković ◽  
Z. Milićević
Keyword(s):  
Human Lymphocytes ◽  
Genotoxic Effects

scholarly journals In Vitro Dissolution Evidence for Sustained and Prolonged Release of Vitamin C in a Phosphatidyl Choline-Enriched Lipid Encapsulation

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 1328-1328
Author(s):  
Mastaneh Sharafi ◽  
Tyler White ◽  
Kelli Fowler ◽  
Kevin Ewell ◽  
Noe Galvan ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Los Angeles ◽  
Vitamin C ◽  
Phosphatidyl Choline ◽  
Release Profile ◽  
In Vitro Dissolution ◽  
Simulated Gastric Fluid ◽  
Prolonged Release ◽  
Lauryl Sulfate

Abstract Objectives In vitro dissolution tests are valuable first-step tools in the development of bioavailable delivery systems, making it possible to assess the performance of novel technologies in releasing active ingredients through the amount dissolved in a dissolution medium. The objective of this study was to evaluate whether phosphatidyl choline-enriched lipid encapsulation releases the majority of vitamin C as ascorbic acid past the stomach in a standard in vitro dissolution procedure and to assess the release profile. Methods A novel phosphatidyl choline-enriched lipid encapsulation that is solid at room temperature was tested for dissolution in a standard dissolution apparatus according to compendial United States Pharmacopeia methods, as per Good Manufacturing Practices for dietary supplements. One serving (included 1000 mg ascorbic acid) was placed into vessels containing simulated gastric fluid (0.1 M HCl) for 120 minutes then changed to simulated intestinal fluid (buffered 2% sodium lauryl sulfate, pH 6.8) for an additional 360 minutes. Aliquots were tested for ascorbic acid concentration at 8 time points by titration. The data was compared with 1000 mg of regular ascorbic acid in a capsule format. Results The phosphatidyl choline-enriched lipid encapsulation released 36% of the vitamin C at 2 hours in the acid phase and released 56% at 3 hours, 67% at 4 hours, 85% at 6 hours and 98% at 8 hours in the intestinal phase. Regular vitamin C filled capsules released 100% of the vitamin C at 30 minutes. Conclusions The dissolution results indicated that phosphatidyl choline-enriched lipid encapsulation can pass the stomach and release the majority of vitamin C in the small intestine. The encapsulation demonstrated a sustained and prolonged release of vitamin C over an 8 hour period. The release profile observed in this in vitro study suggests phosphatidyl choline-enriched lipid encapsulation may improve nutrient absorption and bioavailability which requires further testing including human clinical trials. Funding Sources This study was supported by Lonza (Greenwood, SC) and Ritual (Natals Inc, Los Angeles, CA).

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