Vitamine C - de supervitamine
Misschien wel de belangrijkste vitamine
voor de mensheid is vitamine C. Deze is cruciaal voor een goede gezondheid. Terwijl een
kat, hond etc deze vitamine zelf naar behoefte kan aanmaken is er bij de mens in de
evolutie iets misgegaan. Een Amerikaanse wetenschapper noemt het "het missende stress
hormoon" waardoor onze lever geen vitamine C meer kan aanmaken.
THE MISSING STRESS HORMONE
Stone has described the genetic defect whereby the higher primates lost the ability to
synthesize ascorbate. This defect is caused by a mutated defective gene for the liver
enzyme, L-gulonolactone oxidase. The higher mammals (except for the higher primates)
developed a feedback mechanism which increases ascorbate synthesis under the influence of
external and internal stresses (23).
There are many well-established
functions of vitamin C that help in the handling of stress. When stressed, the higher
mammals can augment these functions by this feedback mechanism. For the higher primates,
including humans, ascorbate can amount to the MISSING STRESS HORMONE (4).
Bron: http://www.orthomed.com/titrate.htm
Ortho - Vitamine C Time Release
Vitamine C time-released is onzin. Vitamine
C wordt boven in het maagdarmkanaal opgenomen in het bloed. Dat betekent dat het tablet
dan al uit elkaar moet zijn gevallen. Zo niet, dan zal een deel gewoon met de ontlasting
in de WC-pot belanden.
http://www.orthoeurope.com/nl/institute_persberichten.php#83
Vitamine C kan belangrijke rol
spelen bij kanker therapie
In Nederland wordt er vaak door de medici
laagdunkend gedaan over de mogelijke rol van hoge dosis vitamine C bij kanker. Maar
wetenschappers zoals Linus Pauling zeggen dit al vele jaren. Ook natuurartsen blijven vaak
hameren op hogere dosis vitamine C dan de armzalige 70mg die het Nederlands
Voedingscentrum voorschrijft als dagelijkse dosis.
Maar nu blijkt uit een studie door
onderzoekers van de McGill Universiteit in Montreal en het Nationale Instituut Gezondheid
in Canada dat hoge dosis Vitamine C direct ingespoten in de aderen en oraal gebruikt toch
verbeteringen van symptomen kan geven en zelfs levensverlengend kan werken bij mensen met
een terminal vorm van kanker. Deze studie beschrijft de effecten van hoge dosis vitamine C
bij een drietal patiënten die blaaskanker, nierkanker en lymfkliekanker hadden. De
resultaten waren dusdanig positief dat er nu meerdere vervolgstudies zullen worden gedaan.
Vitamin C could have a role in cancer
therapy
Researchers at McGill University and
the National Institutes of Health have found in preliminary studies that high-dose vitamin
C given by intravenous and oral routes may improve symptoms and prolong life in patients
with terminal cancer. Several clinical trials of the procedure are set to begin, including
one at McGill.
The study, published in the March 28
issue of the Canadian Medical Association Journal, detailed case reports of three
individual patients with different types of cancer. The patients had unexpectedly long
survival times after receiving high-dose intravenous vitamin C therapy. McGill
University's Dr. L. John Hoffer, of the Faculty of Medicine and Project Director at the
Lady Davis Institute for Medical Research, Jewish General Hospital, co-authored the
article with researchers from the NIH.
Dr. Hoffer said the case reports
indicate that the role of high-dose intravenous vitamin C therapy in cancer treatment
should be explored further. "Our findings are important because they provide
significant grounds to continue this research on vitamin C and cancer therapy," he
said.
Source: University Relations Office
(URO)
For more information: McGill University
- http://www.mcgill.ca/
Canadian Medical Association Journal - http://www.cmaj.ca/
Interne links
Acerola - de bes met de meeste
vitamine C
Op zoek naar fruit met het hoogste
percentage vitamine C ? Dan kom je terecht bij de Acerola bes uit Brazilië. Is nu ook in
poeder vorm te koop en het alternatief voor chemische vitamine C (abcorbaat zuur). Wordt
al volop in Amerika, Japan en Duitsland gebruikt en steeds meer in de duurdere
voedingsupplementen en vitamine C supplementen.
Meer info
Vitamine C boek (Engelstalig)
Een uitgebreid boek van Erwin Stone over de geschiedenis en rol van vitamine C
bij ziektes.
oa de rol bij kanker en vele virussen wordt
genoemd. Een klein stukje:
One thing, however, is certain. Cancer
and its present-day therapy are intense biochemical stresses which deplete the bodies of
cancer victims of their ascorbic acid. The irradiation, the surgery, or the chemotherapy
wit highly toxic materials, are all severe biochemical stresses. Biochemical stresses, in
the majority of the mammals which are able to produce their own ascorbic acid, cause them
to produce more ascorbic acid to combat the stresses. Because of their defective genetic
inheritance, mammals such as guinea pigs, monkeys, and man are dependent on their food
intake for ascorbic acid and their response to stress is ascorbic acid depletion.
Experiments on rats, mice, and guinea pigs are enlightening on this point. When rats and
mice (animals that can make their own ascorbic acid) are exposed to cancer-producing
agents (carcinogens), they start producing much more ascorbic acid in their livers (1).
However, when guinea pigs (animals which, like man, cannot produce their own ascorbic
acid) are exposed to the same carcinogens, their ascorbic acid is used up and not replaced
(2); to quote the authors of this 1955 paper, when mammals are exposed to carcinogens this
will "excite an increased demand for this compound (ascorbic acid) to which the
animals capable of synthesizing it respond by over protection, whereas in those lacking
this power the store is depleted."
Klik hier
Vitamine C en hartaandoeningen
Amerikaans onderzoek - James Enstrom van de
Universiteit van California - over een periode van tien jaar liet zien, dat het aantal
hartaandoeningen bij mannen die dagelijks ten minste driehonderd milligram vitamine C
innamen, met vijftig procent afnam. Bij vrouwen lag dit percentage op veertig. De
levensverwachting nam bovendien met zes jaar toe. De Canadese arts Willis toonde aan, dat
vitamine C aderverkalking in de beenaderen op een natuurlijke wijze kan tegengaan.
Europees onderzoek is zo mogelijk nog duidelijker: het was een bekend gegeven dat
aandoeningen van de kransslagader meer voorkomen in Scandinavië en andere Noord-Europese
landen dan in mediterrane landen.
Professor Gey onderzocht aan de
Universiteit van Basel in hoeverre de verschillen tussen Noord- en Zuid-Europa verband
hielden met de vitaminetoevoer via de voeding. Het bleek dat Noord-Europese mensen
gemiddeld de laagste hoeveelheden vitaminen in het bloed hebben. Ook bleek, dat de opname
van vitaminen veel belangrijker was voor de afname van kransslagaderlijke aandoeningen dan
verlaging van het cholesterolgehalte in het bloed. Vooral de consumptie van zuidvruchten,
wijn, olijfolie en andere vegetarische producten zorgt voor een betere vitamine-inname van
de zuidelijke landen.
Niet alleen vitamine C, maar ook E en
provitamine A (bèta-caroteen) draagt bij aan de vermindering van de kans op een
hartinfarct. De resultaten van onderzoek onder 87.000 deelnemers liet zien, dat
regelmatige inname van vitamine E de kans op aandoeningen van de kransslagader met een
derde doet afnemen. De inname van provitamine A had een vergelijkbaar resultaat. Van geen
enkel geneesmiddel is ooit aangetoond dat het even effectief is in het voorkomen van
hartziekten als deze drie vitaminen.
Bron:
Kruidenvrouwtje
Honden en HD problemen
Kort geleden las ik ook een theorie over doorgefokte honden met heupproblemen. De
auteur zocht de oorzaak in een slechte kwaliteit bindweefsel door een tekort aan vitamine
C die hier een rol bij speelt. Doordat de hond minder vitamine C aanmaakte als normaal
ontstonden er problemen met de heupen (HD). Na veel leeswerk rees het vermoeden dat de
problemen veroorzaakt worden door fabrieksvoeding waarin chemische vitamine C zit ipv de
natuurlijke vorm.
De fabrikanten van dit voedsel voegen
ascorbine zuur toe, maar deze chemische vorm van vitamine C is niet goed genoeg. Dr. Don
Lawson, een voedingsdeskundige: hiervan is bekend dat 80% door de nieren wordt afgevoerd
binnen de 2 uren. Dit wil zeggen dat het lichaam niet de nodige tijd krijgt om chemische
vitamine C op te nemen. Wanneer de hond echter een natuurlijke voeding krijgt met
dagelijks verse groenten, wat rauwe geraspte wortelen en wat gekookte aardappelen, kan hij
de aanwezige natuurlijke vitamine C opnemen en verbruiken tot het vormen van het juiste
collageen.
Vitamine C en kanker
Cellen worden omgeven door collageen en
bindweefsel. Om te kunnen groeien moeten gezonde cellen deze extracellulaire barrières,
waardoor ze worden ingesloten, doorbreken. Dit proces is essentieel voor het leven. De
cellen produceren hiervoor verschillende enzymen, die worden afgescheiden
voor het verteren van bindweefselcomponenten, zoals collageen en elastine. Het is
belangrijk dat die bindweefselvertering wordt gereguleerd, zodat de stabiliteit van het
bindweefsel altijd gehandhaafd blijft. Excessieve
afbraak van bindweefsel maakt deel uit van het ziektebeeld en nadat deze afbraak is
opgetreden, kunnen infectueuze microben, waaronder virussen, het weefsel binnendringen.
In extreme gevallen, zoals bij kanker,
vormen de excessieve productie van verteringsenzymen en de afbraak van collageen en
bindweefsel door kankercellen de gevaarlijke mechanismen met behulp waarvan deze cellen
andere organen binnendringen en daar uitzaaien. In zijn boek ”Kanker” onderbouwt
dr. Rath zijn wetenschappelijke ontdekking dat bepaalde voedingsstoffen, zoals L-lysine,
krachtige natuurlijke remmers van collageenverterende enzymen zijn.
Hij noemt met name de belangrijke rol van
vitamine C bij het in staat houden van deze barriëre tegen het woekeren van kankercellen.
Klik hier voor
het gratis boek
Het is intussen bekend dat rokers vitamine
C onttrekken aan hun lichaam. Als je uitgaat van 25mg per sigaret die je kwijtraakt dan
zal je vitamine C tekort snel oplopen. Doordat vitamine C ook nog eens snel verdwijnt uit
je lichaam (korte halveringstijd) zul je al gauw een cruciale vitamine gaan missen, met
een sinasappeltje extra zal je dus niet veel meer bereiken.
Een ander gevolg van roken is een snellere
veroudering van je huid. Dit wordt veroorzaakt doordat roken bepaalde erfelijke
eigenschappen (genen) activeren die ervoor zorgen dat het collageen in de huid wordt
afgebroken. Collageen zorgt ervoor dat de huid stevig soepel blijft. Bij afbraak van het
collageen wordt de huid slap en rimpelig.
Dus roken breekt je collageen dus ook nog
eens af terwijl die volgens Dr Rath je juist kan helpen celwoekering te voorkomen. Verder
is vitamine C heel belangrijk voor je bloedvaten, door het roken ontstaan dus ook nog eens
problemen in je bloedvaten en leg nu al de basis van je eerste hartaanval. Klinkt hard
maar als je kiest voor roken dan kies je voor een oude kop (huid verouderd stuk sneller)
en verhoog je je kansen op een kort en ongezond leven. En wie lacht er het laatst, de
industrie die je letterlijk heeft leeggezogen en de overheid die flink accijnzen heeft
binnengehaald en daarna een leuke besparing heeft op de aow kosten. Klinkt hard maar zo
zijn de feiten......
Vitamine C bevordert de groei van
collageen
Dit is een stof die het lichaam zelf
produceert om wonden te genezen. Littekenweefsel, genezende wonden maar ook bloedvaten
bestaan voor een belangrijk deel uit collageen. Waarschijnlijk heeft die extra aanmaak de
bloedvatwanden verdikt. Dat is niet 'slecht'. Dat is zelfs 'goed'. Vaatwanden worden
dunner naarmate je ouder wordt en daardoor stijgt de kans op beroertes en infarcten. Het
proces gaat sneller naarmate je bloed meer agressieve stoffen bevat die de vaatwanden
aantasten.
Meer hier
Multinationals achter paniek rond
Vitamine C
De verontrustende berichten over de kankerverwekkende eigenschappen van vitamine C komen
van grote farmaceutische bedrijven. Zij vrezen dat vitamines en andere supplementen het
gebruik van medicijnen zullen verminderen. Daarnaast willen de bedrijven de markt voor
supplementen bederven, zodat er meer vraag komt naar hun veel duurdere functional foods.
Dat zegt supplementenexpert Bill Sardi in een persbericht dat door Michael Mooney is
doorgestuurd.
Meer hier
Vogelgriep en vitamine C
Vitamine C is in staat elke (virus-)
infectie te genezen als het maar in een voldoende hoge dosering wordt ingenomen. En dan
hebben we het niet over milligrammen zoals regulier vaak nog wordt gedacht. Het gaat dan
om tientallen grammen, 10, 20, 30 , 40 of 50 gram per dag.
In feite dien je zoveel in te nemen totdat
je er diarree van krijgt, dan heb je de ‘bowel tolerance dose’ bereikt. Als je
dan iets minder inneemt gaat de diarree vanzelf weer over. Daarmee bestrijdt je niet
alleen de griep, maar ook de ernstige complicaties zoals een longontsteking,
keelontsteking, en zelfs de pijn neemt er door af. En laat je niet weerhouden door artsen
of anderen die beweren dat je het teveel toch weer uitplast en het dus onzin is dat je
zoveel inneemt. Dit soort praatjes zijn allang weerlegd. Elk regulier medicijn plas je uit
en moet je steeds weer opnieuw innemen om een bepaalde concentratie in het bloed te
bereiken. Dat geldt ook voor Vitamine C, je hebt een zekere overdruk in het bloed nodig om
voldoende Vitamine C in de weefsels te krijgen.
Anderen beweren dat je van veel Vitamine C
nierstenen zou krijgen, ook dat is allang weerlegd. Er is nog nooit één geval van
beschreven in de medische litteratuur. Vitamine C is het meest veilige geneesmiddel dat er
bestaat en heeft zelfs in doseringen van 200 gram per infuus geen bijwerkingen.
Meer hier
Robert Carthcart - Vitamine C
onderzoeker
Naast Dr Rath is er nog een belangrijke
vitamine C onderzoeken. Kijk eens op de site van Robert Carthcart:
http://www.orthomed.com
Internationaal
Vitamin C and
Vascular Disease
Scurvy is marked by the breakdown of
collagen tissue throughout the body and frequent infections. Collagen is the protein with
which strong connective tissue is made throughout the body. Sailors were known to have had
scurvy on long voyages, until someone discovered that a little citrus fruit intake avoided
the disease. The way those "scorbutic" (the term we apply to a person with
scurvy) sailors died was by leakage of blood out of their blood vessels. Their blood
vessels literally cracked open and they bled to death.
The same sort of thing happened to many of
our ancestors who lived through the ice ages. Many of them bled to death because they had
little or no ascorbate, and without ascorbate there is no collagen production or repair
throughout the body. The wall of a blood vessel is made of collagen. Therefore, when you
run out of ascorbate, it is only a matter of time until that wall of collagen breaks down,
is not repaired, cracks open and you bleed to death.
http://www.medical-library.net/sites/vitamin_c_and_vascular_disease.html
Vitamin C fulfils many important tasks in
the human body. It is an antioxidant, plays a role in the breakdown of cholesterol, the
detoxification of the liver, supports the absorption of iron, takes part in the production
of hormones and the synthesis of neurotransmitters, the collagen production (connective
tissue), the control of histamine levels (allergies) and carnitine synthesis
(decomposition of fat). Vitamin C has been studied on many occasions and shows
preventative or even curative effects in the case of many diseases. Vitamin C is the most
important antioxidant of our bodies. Antioxidants neutralize free radicals and slow down
the aging process of our bodies. There is a division of labor between Antioxidants.
Vitamin C neutralizes the free radicals in aqueous parts in and around the cells, vitamin
E and carotinoids, on the other hand, in the fatty parts of the cells, such as the cell
membranes. Vitamin C supports and protects the other antioxidants by intercepting free
radicals before they reach the fatty parts of the cells. That way it can reduce the usage
of vitamin E and other antioxidants.
Meer
The Dr. Rath Research Institute applauded
the findings of Dr. Mark Levine and colleagues at the U.S. National Institutes of Health,
which show that vitamin C has the potential to fight cancer when used in high dosages. The
study confirms earlier research findings published in numerous scientific cancer journals
by scientists from the Dr. Rath Research Institute.
The institute's research documents that
vitamin C, when used in combination with the amino acids L-lysine and L-proline and a
polyphenol fraction of green tea known as Epigallocatechin Gallate (EGCG), could not only
kill cancer cells, but limit tumor growth, its infiltration by blood vessels
(angiogenesis), and completely stop the invasion and spread of more than two dozen cancer
cell types. While the NIH study showed a 50 percent decrease in survival of cancer cells
exposed to high doses of vitamin C in five out of nine cancer cell types, the combination
of nutrients used by Rath's group was effective not only in eliminating cancer cells, but
in arresting cancer cell tissue invasion -- a hallmark of metastasis responsible for 90
percent of deaths from cancer. Today, there are no effective measures to stop cancer
metastasis.
Dr. Matthias Rath, founder of the Dr. Rath
Research Institute, said, "The use of lysine, an amino acid, in combination with
ascorbic vitamin C addresses common pathomechanisms of cancer, will lead to a breakthrough
in the control of many forms of cancer and other diseases." Dr. Rath first published
his concept of the natural control of cancer in the Journal of Applied Nutrition in 1992.
Research that confirmed Dr. Rath's approach
was publicized in an advertisement in USA Today on March 8, 2002. Further research was
presented at the 19th Annual Miami Breast Cancer Conference in February of 2002; at the
American Association of Cancer Research Special Conference in Cancer Research in South
Carolina in October of 2002; at many other national and international conferences; and in
many publications. The most recent findings can be found at the Breast Cancer Research Web
site at http://breast-cancer-research.com/content/7/3/R291.
"By using nutrient synergy and
defining correct biological targets, we could achieve superior physiological effects,
which is not possible with a single nutrient therapy, even if applied at extreme
doses," said Dr. Aleksandra Niedzwiecki, director of research at the institute.
The Dr. Rath Research Institute is calling
for a radical change in the treatment of cancer, one that takes advantage of new natural
approaches. Conventional approaches, such as chemotherapy and radiation, have been
unsuccessful in reducing the high mortality rate of the disease, have contributed only to
the accelerated cost of health care, and led to the development of new diseases that
result from the side effects of these treatments.
The Dr. Rath Research Institute offers
innovative, safe, effective, and natural solutions to cancer. To learn more, visit www.drrathresearch.org.
Source: Dr. Rath Education Services
USA, BV
Ascorbid Acid can kill cancer cells
Pharmacologic ascorbic acid concentrations selectively kill cancer cells: Action
as a pro-drug to deliver hydrogen peroxide to tissues
Meer
Interessante studies mbt Vitamine C
1. Cathcart, R.F. Clinical trial of vitamin
C. Medical Tribune, June 25, 1975.
2. Cathcart, R.F. Clinical use of large
doses of ascorbic acid. Presented at the annual meeting of the California Orthomolecular
Medical Society, San Francisco, February 19, 1976.
3. Cathcart, R.F. Vitamin C as a
detoxifying agent. Presented at the annual meeting of the Orthomolecular Medical Society,
San Francisco, January 21, 1978.
4. Cathcart, R.F. Vitamin C - The missing
stress hormone. Presented at the annual meeting of the Orthomolecular Medical Society, San
Francisco, March 3, 1979.
5. Cathcart, R.F. The method of determining
proper doses of vitamin C for the treatment of disease by titrating to bowel tolerance. J.
Orthomolecular Psychiatry, 10:125-132, 1981.
6. Klenner, F.R. Virus pneumonia and its
treatment with vitamin C. J. South. Med. and Surg., 110:60-63, 1948.
7. Klenner, F.R. The treatment of
poliomyelitis and other viral diseases with vitamin C. J. South. Med. and Surg.,
111:210-214, 1949.
8. Klenner, F.R. Observations on the dose
and administration of ascorbic acid when employed beyond the range of a vitamin in human
pathology. J. App. Nutr., 23:61-88, 1971.
9. Klenner, F.R. Significance of high daily
intake of ascorbic acid in preventive medicine. J. Int. Acad. Prev. Med., 1:45-49, 1974.
10. Stone, I. Studies of a mammalian enzyme
system for producing evolutionary evidence on man. Am. J. Phys. Anthro., 23:83-86, 1965.
11. Stone, I. Hypoascorbemia: The genetic
disease causing the human requirement for exogenous ascorbic acid. Perspectives in Biology
and Medicine, 10:133-134, 1966.
12. Stone, I. The Healing Factor: Vitamin C
Against Disease. Grosset and Dunlap, New York, 1972.
13. Pauling, L. Vitamin C and the Common
Cold. W.H. Freeman and Company, San Francisco, 1970.
14. Pauling, L. Vitamin C, the Common Cold,
and the Flu. W.H. Freeman and Company, San Francisco, 1976.
15. Cameron, E. and Pauling, L.
Supplemental ascorbate in the supportive treatment of cancer: Prolongation of survival
times in terminal human cancer. Proc. Natl. Acad. Sci. USA, 73:3685-3689, 1976.
16. Cameron, E. and Pauling, L. The
orthomolecular treatment of cancer: Reevaluation of prolongation of survival times in
terminal human cancer. Proc. Natl. Acad. Sci. USA, 75:4538-4542, 1978.
17. Cameron, E. and Pauling, L. Cancer and
Vitamin C. The Linus Pauling Institute for Science and Medicine, Menlo Park, 1979.
18. Williams, R.J. Biochemical
Individuality. John Wiley, New York, 1956. University of Texas Press, Austin, Texas, 1973.
19. Siegel, B.V. Enhancement of Interferon
Response by poly(rI).- poly(rC) in Mouse Cultures by Ascorbic Acid. Nature 254:531-532,
1975.
20. Siegel, B.V., Morton, J.I. Vitamin C
and the Immune Response. Experientia 33:393-395, 1977.
21. Lewin, S. Vitamin C: Its Molecular
Biology and Medical Potential. Academic Press, London, 1976.
22. Kalokerinos, A. Every Second Child,
Thomas Nelson, Australia, 1974.
23. Subramanian, N. et al. Detoxification
of histamine with ascorbic acid. Biochemical Pharmacology. 27:1671-1673, 1973.
24. Murata, A. Virucidal activity of
vitamin C: Vitamin C for the prevention and treatment of viral diseases. Proceedings of
the First Intersectional Congress of Microbiological Societies, Science Council of Japan,
3:432-442, 1975.
25. Salaman, M. Fighting infection-the cat
and the "C". Let's Live, 128-130, April 1980.
26. Libby, A.F. and Stone, I. The
hypoascorbemia-kwashiorkor approach to drug addiction therapy: A pilot study. J.
Orthomolecular Psychiatry, 6:300-308, 1977.
27. Greenwood, J. Optimum vitamin C intake
as a factor in the preservation of disc integrity. Medical Annals of the District of
Columbia, 33:274-276, 1964.
28. Cousins, N. Anatomy of an Illness as
Perceived by the Patient. W.W. Norton & Company, New York, 1979.
29. Williams, R.J. The Prevention of
Alcoholism Through Nutrition. Bantam Books, New York, 1981.
30. Campbell, G.D. Jr., Steinberg, M.H. and
Bower, J.D. Ascorbic acid induced hemolysis in G-6-PD deficiency. Ann. Int. Med. 82:810,
1975.
31. Herbert, V. and Jacob, E. Destruction
of vitamin B12 by ascorbic acid. JAMA, 230:241-242, 1974.
32. Belfield, W.O. and Stone, I.
Megascorbic prophylaxis and megascorbic therapy: A new orthomolecular modality in
veterinary medicine. Journal of the International Academy of Preventive Medicine, 2:10-26,
1975.
Hemilä, Harri and Herman, Zelek.
Vitamin C and the common cold: a retrospective analysis of Chalmers' review. Journal of
the American College of Nutrition, volume 14, number 2, pp. 116-123 (1995)
Drs. Hemilä and Herman examined the influential review of the efficacy of vitamin C
against the common cold published by Dr. Thomas Chalmers in 1975, which they found to be
seriously flawed due to data errors and the inclusion in Chalmers' analysis of a clinical
study using only 25-50 mg/day of supplemental vitamin C. Using the correct data from the
original publications, Drs. Hemilä and Herman found that supplemental vitamin C in doses
from 1-6 grams/day significantly decreased both the duration and symptoms of the common
cold.
Harakeh, Steve and Jariwalla,
Raxit. Ascorbate effect on cytokine stimulation of HIV production. Nutrition (supplement),
volume 11, number 5, pp. 684-687 (1995)
Drs. Harakeh and Jariwalla investigated the effects of vitamin C and AZT, a commonly
prescribed AIDS drug, on the production of the human immunodeficiency virus (HIV) in cells
stimulated with tumor necrosis factor alpha (TNF-a, an inflammatory cytokine. (Cytokines
are small proteins that trigger cell differentiation or proliferation and also regulate
the immune response.) TNF-a caused a very significant increase in viral production in
control cells, as assayed by the amount of reverse transcriptase (RT), a viral enzyme
whose amount correlates with viral replication. However; pretreatment of the cells with
ascorbate significantly reduced the amount of extracellular RT indicating inhibition of
viral replication, whereas AZT had no effect.
Jariwalla, Raxit. Micro-nutrient
imbalance in HIV infection and AIDS: relevance to pathogenesis and therapy. Journal of
Nutritional & Environmental Medicine, volume 5, pp. 297-306 (1995)
Dr. Jariwalla reviewed the causes and
consequences of micronutrient imbalance in HIV-infected persons and AIDS patients.
Abnormalities in micronutrient status due to malnutrition, oxidative stress, or
malabsorption contribute to immunological impairment and AIDS-related pathologies. Dr.
Jariwalla noted that prospective studies of asymptomatic HIV-infected persons indicate
that micronutrient consumption or repletion may delay the onset of AIDS.
Jariwalla, Raxit and Harakeh,
Steve. Antiviral and immunomodulatory activities of ascorbic acid. In Subcellular
Biochemistry, Volume 25: Ascorbic Acid: Biochemistry and Biomedical Cell Biology, edited
by J. Robin Harris, NY: Plenum Press, pp. 215-231 (1996)
Drs. Jariwalla and Narakeh reviewed the virucidal and immunostimulatory effects of vitamin
C presented in scores of studies published in the last three decades. Vitamin C has been
found to inhibit viral infectivity by inactivating viruses and by affecting viral
replication. Additionally, vitamin C promotes immunological functions, such as
phagocytosis, chemotaxis, and neutrophil adhesion, and acts as a powerful antioxidant,
thereby alleviating oxidative stress engendered by viral infection. Ascorbate is also
involved in the regulation or synthesis of crucial immune system molecules, such as
cytokines, antibodies, and interferon. The authors cite numerous relevant animal, cell
culture, and human studies and, on the basis of positive results of clinical studies using
small amounts of supplemental vitamin C, conclude that more clinical studies are needed to
determine the optimal therapeutic dose of vitamin C.
Harakeh, Steve and Jariwalla,
Raxit. NF-kB-independent suppression of HIV expression by ascorbic acid. AIDS Research and
Human Retroviruses, vol.13, number 3, pp. 235-239 (1997)
In this paper; the authors narrowed the focus on the molecular mechanism by which vitamin
C inhibits HIV, a retrovirus, by determining that the inhibition by ascorbate occurs at a
step after transcription of the viral genetic material, whereas other antioxidants inhibit
HIV replication by blocking transcription. (In most organisms, DNA is transcribed into
RNA, which then controls the synthesis of proteins, but in retroviruses, RNA is
transcribed into DNA, which then becomes integrated into the host cell's genomic DNA.)
Jariwalla, Raxit and Harakeh,
Steve. Mechanisms underlying the action of vitamin C in viral and immunodeficiency
disease. In Vitamin C in Health and Disease, edited by Lester Packer and JÜrgen Fuchs,
NY: Marcel Dekker, pp. 309-322 (1997)
This book chapter reviews the manifold mechanisms by which vitamin C exerts antiviral and
immunostimulatory effects. Ascorbate potentiates the immune system, spares glutathione (an
important intracellular antioxidant), combats oxidative stress, neutralizes extracellular
free radicals liberated by immune cells in response to pathogens, selectively kills
virally infected cells, suppresses viral replication, and directly inactivates viruses.
Roomi, M. Waheed and Tsao, Constance. Effect of ascorbic acid deficiency on plasma
prothrombin time and partial thromboplastin time in guinea pigs. Clinica Chimica Acta,
volume 248, pp. 209-211 (1996)
Using guinea pigs, Drs. Roomi and Tsao determined the clotting, or coagulation, time for
the plasma of guinea pigs fed different amounts of vitamin C. They found that ascorbic
acid deficiency resulted in coagulation abnormalities, i.e. prothrombin time was increased
and thromboplastin time was decreased, and that these defects were corrected by increasing
the ascorbic acid intake.
Ivanov, Vadim; Ivanova, Svetlana;
and Niedzwiecki, Aleksandra. Ascorbate affects proliferation of guinea pig vascular smooth
muscle cells by direct and extracellular matrix-mediated effects. Journal of Molecular and
Cellular Cardiology, in press (1997)
The proliferation of vascular smooth muscle cells (VSMC) and the proteins secreted by them
into the extracellular matrix, which forms a structural lattice for cells, contribute to
the development of atherosclerotic plaque. In cell culture experiments, the authors found
that these events can be modified by high concentrations of vitamin C, which inhibit the
proliferation of VSMC directly and indirectly by modifying the extracellular matrix
deposited by VSMC. Vitamin E also inhibited DNA synthesis by VSMC, resulting in decreased
cell proliferation, but did not alter the extracellular matrix.
Dunham, Wolcott; Tsao, Constance; Barth, Roger; and Herman, Zelek. Protection by
dietary ascorbate of guinea pigs from neurolathyrism. Nutrition Research, vol. 15, pp.
993-1004 (1995)
Neurolathyrism, a paralytic disease caused by consumption of Lathyrus sativus, or the
grass pea, is prevalent in many regions of the world. The grass pea provides protein and
grows readily in areas of drought or flooding. However; the pea and its flour contain
several neurotoxins, including B-N-oxalylamino-L-alanine (BOAA), that can cause paralysis
in humans and guinea pigs, which, like humans, are unable to synthesize vitamin C and
provide a good experimental model to study this disease. Dr. Dunham and his colleagues
found that guinea pigs on an ascorbate-deficient diet given an injection of an extract of
the pea containing BOAA died or exhibited paralysis, whereas guinea pigs supplemented with
vitamin C were completely protected or showed only minor; transient weakness. These
results may have important relevance to humans who rely on the grass pea for nutrition but
succumb to its toxicity.
Roomi, M. Waheed and Tsao,
Constance. Ascorbic acid protection of guinea pigs against B-aminopropionitrile induced
neurolathyrism. Research Communications in Biological Psychology and Psychiatry, vol.20,
numbers 3 and 4, pp.113-122 (1995)
To determine the mechanism of protection against neurolathyrism afforded by vitamin C,
Drs. Roomi and Tsao compared the effect of two free-radical trapping agents, vitamin C and
N-tert-butyl-a-phenylnitrone (BPN), on the neurotoxicity in guinea pigs of another
neurotoxin, B-aminopropionitrile (BAPN), contained in the grass pea. Both free-radical
scavengers protected the guinea pigs from neurolathyrism when given before or with BAPN,
indicating that free radicals generated by the neurotoxin are probably responsible for the
symptoms of the disease.
Tsao, Constance; Dunham, Wolcott; and Leung; Ping. Growth control of human colon
tumor xenografts by ascorbic acid, copper, and iron. The Cancer Journal, vol. 8, pp.
157-163 (1995)
The authors of this study previously reported that a combination of ascorbic acid and
copper sulfate inhibited the growth of small fragments of human mammary or lung tumors
explanted in mice. Fragments of the human tumors were implanted under the renal capsule of
mice and measured after six days of treatment. This method allows for evaluation of the
immune-independent anti-cancer effect of the test agents, since the immune system does not
respond quickly to the xenograft. In another set of experiments reported in this paper,
Drs. Tsao, Dunham, and Leung showed that the growth of human colon adenocarcinoma explants
in mice was also inhibited by a combination of large amounts of ascorbic acid in the diet
and copper or iron ions supplied in the drinking water. The administration of metal ions
without vitamin C increased tumor growth, whereas vitamin C alone suppressed tumor growth
in some animals. The combination of ascorbic acid and metal ions proved much more
effective than the vitamin alone, indicating that the anti-cancer effect was due to
products formed by the oxidation of vitamin C, which is catalyzed by the metal ions,
rather than to its vitamin activity.
Tsao, Constance and Young,
May. Molecular structure-dependent cytotoxic effect of ascorbate derivatives. In Vitro
Cellular and Developmental Biology, volume 31, pp. 87-90 (1995)
In this letter, Dr. Tsao and Ms. Young suggest that the anticancer, cytotoxic effect of
ascorbate derivatives and degradation products are dependent on the chemical structure,
rather than the vitamin activity, of ascorbic acid. They compared the cytotoxic effect of
derivatives of vitamin C formed by oxidation, other degradation products of vitamin C, and
its isomers on mouse leukemia cells. Their results suggest that the cytotoxic moiety
resides in the enediol lactone ring structure of the molecules. This line of research may
suggest novel therapeutics for cancer treatment.
Roomi, M. Waheed and Tsao,
Constance. Dietary ascorbic acid does not alter the expression of the 58-kDa acetaminophen
binding protein nor the arylation of other cytosolic proteins in guinea pig liver.
Research Communications in Pharmacology and Toxicology, volume 1, number 4, pp. 269-278
(1996)
Acetaminophen, an over-the-counter analgesic, is metabolized in a similar manner by most
animal species. However; susceptibility to toxicity of acetaminophen overdose, which may
result in liver necrosis, varies among species. Drs. Roomi and Tsao determined that the
major protein in mouse and human livers that binds acetaminophen is not synthesized in
guinea pigs, thereby providing the basis for additional studies to determine the mechanism
involved in acute acetaminophen toxicity in guinea pigs and how this may be influenced by
ascorbic acid.
Roomi, M. Waheed; Ogg, M.; Tsao,
Constance; and Gibson, G. Ascorbic acid deficiency decreases the expression of CYP4A1 in
liver microsomes of guinea pigs. Research Communications in Molecular Pathology and
Pharmacology, volume 95, number 1, pp .3-10 (1997)
The cytochrome P-450 system is the main drug metabolizing system in humans. The activity
of many of the enzymes comprising this system is affected by nutritional status, age,
gender; and other factors. Dr. Roomi and his colleagues measured the amount of a
particular cytochrome P-450, CYP4A1, which is induced in the liver by the hypolipidemic
drug clofibrate, in guinea pigs. They found that the expression, or synthesis, of total
cytochrome P-4S0 and of CYP4A1 decreased in ascorbic acid deficient animals, which may
indicate less efficient detoxification of the drug.
Netke, Shrirang; Roomi, M. Waheed;
Tsao, Constance; and Niedzwiecki, Aleksandra. Ascorbic acid protects guinea pigs from
acute aflatoxin toxicity. Toxicology and Applied Pharmacology, volume 143, pp.429-435
(1997)
Aflatoxins are mycotoxins produced by molds
that grow on grain and nuts. Their consumption is associated with liver damage and liver
cancer in many regions of the world (see George Bailey's article in this issue). Dr. Netke
and his colleagues gave an oral dose of aflatoxin B1 to guinea pigs fed diets containing
no vitamin C or a small amount of vitamin C, or given a larger amount of vitamin C by
mouth. 70% of the unsupplemented guinea pigs died, but all of the vitamin C-supplemented
animals survived. The largest dose of vitamin C also protected the animals' livers from
any pathological abnormalities. These results may be applicable to humans, who might be
spared the misery of aflatoxin induced liver cancer.
Vitamin C: Cold comfort unless
you're stressed
Vitamin C has been proven ineffective in
combating the common cold in most people, but significantly effective in reducing the
incidence of cold in people exposed to cold and/or physical stress, such as marathon
runners, skiers and soldiers, according to a new study.
The new review of the role of vitamin C in
the prevention and treatment of the common cold, conducted by ANU Professor Bob Douglas
and Finnish colleague Associate Professor Harri Hemilä, includes findings from 55
comparative studies that have been carried out over the past 65 years.
The reviewers set out to discover whether
vitamin C in doses of at least 200 milligrams daily reduces the incidence or duration of
the common cold when used either as continuous preventive treatment or after the onset of
cold symptoms. The results of the research are published in the June issue of PLoS
Medicine, an international peer reviewed, open access online medical journal.
“We found that incidence of the common
cold was not altered in 23 community studies representing 10,435 participants where
regular preventive doses as high as two grams daily were used,” Professor Douglas
said.
“However, in a subgroup of six
studies, representing 642 participants who were marathon runners, skiers or soldiers
exposed to significant cold and/or physical stress, incidence of common colds was reduced
by 50 per cent by those taking vitamin C.
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