2. • It is a powerful antioxidant as well as a co-factor for a
number of biosynthetic and gene controlling enzymes.
Vitamin C aids immune protection by supporting a variety of
immunological functions.
• Vitamin C promotes epithelial cells. The skin’s oxidant
scavenging activity is boosted, providing a barrier against
infections, potentially shielding against oxidative damage in
the environment.
• It’s also required for apoptosis and the removal of dead cells.
. Macrophages remove neutrophils from infected sites,
reducing necrosis and netosis. Vitamin C involvement in
lymphocytes less apparent, however, it has been
demonstrated to improve B and T-cell differentiation and
proliferation, most likely due to gene regulatory properties.
Abstract
3. Continue…
Vitamin C insufficiency lowers immunity and makes more susceptible to
disease. Vitamin C supplementation appears to be effective in both
preventing and treating cancer. Infections of lungs and rest of body should be
treated. Vitamin C intakes of 100-200mg/day that give acceptable, if not
saturated plasma level, cell and tissue levels should be optimized.
Treatment of established infections, on the other hand, necessitates a great
amount of time and effort. Large vitamin dosage to compensate for the
enhanced inflammatory response and metabolic demand.
4. INTRODUCTION
The essential nutrient vitamin C can not be produced in the body of human
due to loss of its enzyme.(Carr & Maggini, 2017)
Vitamin C is also called as ascorbic acid. The disease or pathogen frightening
system is an elegant network that requires collaborating function of different
organs, tissues, cells, enzymes etc. in body to preserve its function against
dangerous invading substances (for example viruses, bacteria microbes
etc.)(Parkin & Cohen, 2001)
Immune system consists of components of membrane barriers and hormonal
component of natural (innate) and adaptive immune system.(Carr & Maggini,
2017)
5. Vitamin C role in immune process can be suggested by
its rapid consumption during infection and ascorbate
high concentration in leukocyte(Thomas & Holt, n.d.)
Vitamin C role in immune response can be classified into
two functional areas (i) Phagocyte create reactive
oxygen species by their oxidative destruction of foreign
invader. Vitamin C play in neutralizing these foreign
invaders. (II) In immune system vitamin C also has effect
on its different component.(Jacob & Sotoudeh, 2002)
Vitamin C is important in collagen production and act as
co factor in production of catecholamine, cholesterol,
amino acids. Vitamin C is a gluconic acid lactone
originate from glucuronic acid and water soluble
ketolactone with two ionizable hydroxyl group(Telang,
2013)
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6. It is by nature antioxidant exist as D- Ascorbic acid and L- ascorbic
acid. Both of these isomeric and exchangeable.
Ascorbic acid is a potent free radical scavenger, protecting cells
against oxidative damage. Its cytotoxic activity relies on its ability to
reactive oxygen species rather than its popular antioxidant action.
Ascorbic acid may have prooxidant and even mutagenic effects in the
presence of transition metals.(Gallie, 2013) .
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7. The available data suggested the role of vitamin C in immune
response especially in the mobility of leukocytes but as yet there is
no justification for the intake of vitamin C for the prolonged period
of time.(Thomas & Holt, n.d.)
Age RDA
0-12 months 40-50 mg
1-3 years 15mg
4-8 years 25mg
9-13 years 45mg
Table no 1: Recommended dietary allowance of vitamin c
(Carr & Maggini, 2017)
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8. Role of ascorbic acid in
treatment of cancer
Ascorbic acid proposed as chemotherapeutic agent but it
has controversial history
10g/day of ascorbic daily in some reports was seen
effective in wellbeing of patient
Ascorbic acid kills cancer cells rather than normal cells
Its intravenous dose not given to fulfill any deficiency but
to some extent oxidative stress on cancer cells
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Studies showed that selectively higher concentration of
ascorbic acid in cancer cells results in depletion of acid in
normal cells
Ascorbate and its derivatives exerts inhibitory effect on
growth of tumor cells
Ascorbate needed for hydroxylation of amino acids and
mixed function oxidase(group of microsomal enzymes)
One of the anticancer function of ascorbate is to enhance
secretion of sodium from urine
10. Role as barrier of skin
Skin plays a vital role as barrier stopping the entrance of
dangerous agents
Skin constitute two layers
1st layer-------epidermis
2nd layer------dermis
Most fencing function of skin performed by epidermis
composed of cells called keratoniytes
The level of vitamin C is higher in 1st layer inspite of 2nd
Epidermal layer face challenging environment in
transportation of nutrient as blood vessels are absent it
11. Continue…
Using a transporter vitamin C gathered actively in cells of
dermis and epidermis
Vitamin C also act as cofactor for hydroxlase enzyme lysyl
and prolyl that aids in stabilizing tertiary structure of
collagen
Vitamin C plays a part in forming collagen and skin barrier
,opposing oxidation prevent wrinkles
Also plays a important role in resisting oxidative that is
caused due to UV radiations , prevents melanogenesis ,
differentiate dermis cells and vitamin C has been used as
a treating agent at a clinical level for a longer period of
time.
12. Ascorbic acid and its role in
heart health:
The antioxidant properties of vitamin C support the theory that it also has
role in prevention of cardiovascular diseases.
Vitamin C, for example, has been demonstrated to inhibit monocyte
adherence to the endothelium.
Vitamin C has been proven to boost endothelial nitric oxide production, which
leads towards increasing vasodilation and lowering blood pressure.(Moser &
Chun, 2016)
In older men, higher plasma vitamin C was correlated with lowers the risk of
heart failure regardless of the presence or absence of myocardial
infarction.(Ellulu, 2017)
Supplementation of vitamin C has a defensive impact on different disease
conditions, mostly cardiovascular disease, common cold and cancer. Vitamin C
along with supplemental consumption >400mg/d seems to be more evident
effects of heart-protection.(Schlueter & Johnston, 2011)
13. Bacterial destruction and
engulfment
Neutrophils have demonstrated to influence extracellular destruction
by production of neutrophil extracellular traps, to which vitamin C act
as controller(Bozonet et al., 2015)
Neutrophil attachment and movement are reduced in patients with
severe infections while formation of free radical enhances(Danikas et
al., 2008).
Studies on people having genetic issues in neutrophil activity have
manifested reduced infection onset through vitamin C
supplementation and appropriate progression in bactericidal function
of neutrophils(Bozonet et al., 2015).Hirsh et. al have described
reduced phagocytosis by neutrophils an monocytes in patients with
severe infections(Danikas et al., 2008)
14. Lymphocyte activity
Vitamin C plays pivotal role in developmental diversity and growth of
premature T-cell(Carr & Maggini, 2017)
Ascorbic acid is needed in vitro for early maturation of T-cells
because it affects synthesis block from DN to DP
.
Ascorbic acid increases the synthesis speed of lymphocytes(van
Gorkom et al., 2018).
In vivo studies, suggested that conjugation of vitamin C with
lymphocytes increases progression(Carr & Maggini, 2017).
Sensitized lymphocytes from normal species were insufficient in
displaying delayed type-hypersensitivity to scorbutic individuals.
15. Vitamin C and COVID 19
One of the best properties of vitamin c is that it is antioxidant in
nature.
It protects the tissues and cells of the body from oxidative damage by
scavenging reactive oxygen species.(Carr, 2020).
Vitamin can act as anti-viral, anti-inflammatory, anti-oxidant and
immunomodulator agent, which makes it a potential candidate for the
management of COVID 19.
Promising results were shown by using high dose of vitamin c in China
and United States.
After administration of vitamin c significant decrease in inflammatory
markers which includes D-dimer and ferritin was seen.
16. Continue…
Some trials are ongoing in coadministration of vitamin D
and vitamin C to find out about their roles for treatment
of mild to moderate COVID 19 infections.(Hiedra et al.,
2020).
Vitamin C is cheap, readily available and no adverse
effect was reported by the administration of vitamin C for
short period of time.
Owing to its pharmacological properties it can be
suggested to include vitamin C as part of treatment of
COVID 19 if the ongoing trials provide positive
results.(Abobaker et al., 2020).