3. In 1956s Dr. Denham Harman studied -
The rate of living theory, which holds that lifespan is an inverse
function of metabolic rate which in turn is proportional to
oxygen consumption .
Rebbeca Gershman's observation that oxygen toxicity and
radiation toxicity could be explained by the same underlying
phenomenon: oxygen free radicals.
On basis of these , he proposed that-
Cells continuously produce free radicals by normal metabolism and
oxidation of organic compounds and these free radicals damage
cellular macromolecules ( like DNA , lipid , proteins ) and due
accumulation of these damage over time period cause aging.
In 1972s, Denham Harman modified his theory-
About 95% energy of a cell is produce in mitochondria and about
97% - 99% of oxygen is use in energy formation and 1%- 3%
oxygen is utilize in reactive oxygen species formation.
It states that reactive oxygen species (ROS ) are produce in
mitochondria during ETC cycle and they cause damage to
macromolecules including lipid , protein, DNA of mitochondria
and nucleus which lead to aging
Dr. Denham
Harman
4. A free radical is defined as any species that contains one or more unpaired
electron occupying an atomic or molecular orbital.
As they are highly reactive and unstable, they pull electron from other
molecules and cause affected molecules to become free radical and then
new free radical pull electron to next molecules , so chain is produce .
Examples of free radicals:.
Superoxide anion, Hydroxyl radical , Peroxynitrite,
Hydrogen radical, Nitric oxide , Lipid peroxyl .
8. Certain “antioxidant” compounds might
“scavenge” these damaging free oxygen
radicals and prevent cellular destruction
and aging. Vitamin C, vitamin E, and
betacarotene, often referred to as
“antioxidant vitamins”, have been
suggested to limit oxidative damage in
humans and lower the risk of certain
chronic diseases.
9. Any synthetic or natural substance that delay or inhibits oxidative damage
to a target molecule and capable to neutralize free radicals by donating
electron or hydrogen molecule.They prevent cell damage and tissue
damage and act as scavenger.
ANTIOXIDANTS
Antioxidant
enzymes
Antioxidant
Vitamins
11. Vitamins must be INGESTED everyday –
and are found in foods like fresh fruits &
vegetables, nutrient dense protein foods
and whole grains.
To get enough of each vitamin it is best to
always eat a wide and colorful variety of
produce.
Dark leafy green vegetables have the
most vitamins & minerals in them!
12. Two Groups of Vitamins
FAT SOLUBLE:
Vitamins A,D,E,K
(All Dogs Eat Kittens)
Transported through
the body in fat.
Too much can cause a
toxicity.
WATER SOLUBLE:
Vitamins B & C
(Be Cool)
Transported through body
in water –excreted in
urine.
Deficiency keeps body
from operating at
capacity.
13. Vitamin A
Function: Promote good vision,
normal growth, and healthy nerve
function
Sources: Liver, yellow & orange
fruits and vegetables, pears,
and broccoli
Prevents: skin problems and
unhealthy hair, poor vision and
night blindness.
TOXICITY can cause liver
damage and severe birth defects.
Carotene in carrots converts to Vitamin A
14. nyctalopia: inability
to see clearly in dim light;
due to a deficiency of
vitamin A or to a retinal
disorder.
Night Blindness
15. Vitamin D
Function: Formation of strong
Bones & Teeth.
Sources: Dairy Products, seafood,
eggs, mushrooms, cereal, pork.
Prevents: Malabsorption of
calcium; Rickets / Osteoporosis
TOXICITY = calcium build up /
bone spurs
16. Rickets
A deficiency disease resulting from a lack of
Vitamin D or from insufficient exposure to sunlight.
Characterized by softening of developing bone,
bow legs, malnutrition, and enlargement of the liver
and spleen.
17. Vitamin E
(alpha tocopherol)
Function: Antioxidant; slows down
aging, promotes healthy skin & hair
Sources: Nuts, seeds, green leafy
vegetables, avacados, grains (germ)
Prevents: Cellular degeneration
(Vitamin E and its analogs are used to
prevent and repair cell and tissue damage
during radiation therapy).
TOXICITY can cause blurred vision,
nausea, diarhea, dizziness, fatigue
18. Toxicities & consumption
Regular consumption of
more than 1,000 mg
(1,500 IU) of tocopherols
per day may be expected
to cause hypervitaminosis
E, with an associated risk
of vitamin K deficiency and
consequently of bleeding
problems.
Recommended Dietary
Allowances (RDAs) for
Vitamin E (Alpha-Tocopherol)
Age Males
0–6 months* 4 mg
(6 IU)
7–12 months* 5 mg
(7.5 IU)
1–3 years 6 mg
(9 IU)
4–8 years 7 mg
(10.4 IU)
9–13 years 11 mg
(16.4 IU)
14+ years 15 mg
(22.4 IU)
19. Deficiency
ataxia
myopathies
peripheral neuropathy
retinopathy
impairment of the immune
response
red blood cell destruction (esp. in
Premature infants)
hemolytic anemia
Atherosclerosis
a 71% decrease in the risk of
advanced prostate cancer.
20. Vitamin K
Function: Assists with blood
clotting; essential for bone healing
and body repair.
Source: Dark green, leafy
vegetables, cabbage, liver,
cauliflower.
Prevents: Hemorrhaging
No known TOXICITY
21. Vitamin C
(ascorbic acid)
Function: Aids in wound
healing, helps promote
healthy immune system,
forms collagen.
Sources: Citrus Fruits,
Cantaloupe, strawberries,
pineapple, broccoli
Prevents: Scurvy
TOXICITY = acid sores in
soft tissues of mouth
22. Scurvy
A lack of (DEFICIENCY) of Vitamin C
characterized by weakness, anemia,
bruising, inflamed pores, bleeding
gums and loose teeth.
23. B Vitamins….
“Vitamin Complex”
a GROUP of vitamins…..
B1 = Thiamine
B2 = Riboflavin
B3 = Niacin
B6 = Pyridoxine
B9 = Folacin / Folic Acid
B12 = Cobalamin
24. Vitamin B1 =Thiamine
Function: Healthy nerve
function and muscle tissue,
digestive system, energy
metabolism.
Sources: Milk, grains,
poultry, fish, dried beans
Prevents: Beriberi
No known TOXICITY
25. Beriberi
Caused by a deficiency of thiamine
(vitamin B1) that affects many
systems of the body, including the
skin, muscles, heart, nerves, and
digestive system.
Beriberi means…
"I can't, I can't" in Singhalese,
which reflects the crippling effect
it has on its victims.
beriberi is primarily seen in people
with chronic alcoholism.
26. Vitamin B2 =Riboflavin
Function: Growth, nerve function,
digestion, works with protein for
maintenance, energy metabolism.
Sources: Milk, grains, green
vegetables, meat, fish
Prevents Premature aging; Cheilosis
No known TOXICITY
27. Cheilosis
A disorder of the lips
marked by scaling and
fissures at the corners
of the mouth; caused
by a lack of
(DEFICIENCY) of
riboflavin
28. Vitamin B3 = Niacin
Function: Promotes
healthy skin and tissues,
digestion, and nervous
system.
Sources: Milk, grains,
poultry, fish.
Prevents: Pellagra
No known TOXICITY
29. Pellagra
An inability to
absorb Niacin (B3)
or the amino acid
tryptophan may
cause scaly sores,
cellular
degeneration,
mucous PH
imbalance, and
mental barriers.
30. Vitamin B6 = Pyridoxine
Function: Healthy brain
function, formation of red
blood cells, immune
system
support.
Sources: Beans, legumes,
nuts/seeds, eggs
,meat/fish.
Prevents: Helps fight
infection.
No known TOXICITY.
31. Vitamin B9=Folacin
(Folic Acid / Folate)
Functions: Age related
memory, vision and hearing
loss; promotes healthy red
blood cells, maintains body
enzymes.
Sources: beans/ legumes
citrus fruit, dark green
vegetables, grains, meats,
poultry/eggs, liver.
Prevents: Neural Tube birth
Defects, anemia and Vitiligo.
32. Neural Tube Birth Defects:
(NTD) is lack of (DEFICIENCY)
of Folic acid causing a congenital
malformation which occurs
between the 20th and 28th day
after conception.
The cells of the neural plate
make up nervous system. The
cells fold back onto themselves in
order to create what is called the
neural tube, which becomes the
back bone and spinal cord.
34. Vitiligo…
Skin condition in which there
is a loss of brown color
(pigment) from areas of skin,
resulting in irregular white
patches.
Caused by lack
(DEFICIENCY) of Vitamin B
or Folic Acid and other
vitamins such a B12, C and
copper & zinc.
35. Vitamin B12 = Cobalamin
Function: Healthy red blood cell & marrow,
nervous system function, sperm production,
strong immune system. Improves mental
energy, memory, protects against allergies
and toxins (cyanide in cigarettes)
Sources: Milk, eggs, liver, dairy products,
fish, and shellfish
Prevents: Pernicious Anemia, intestinal malabsorption
TOXICITY = slight stomach upset
36. Pernicious Anemia
Chronic disease cause by
lack of (DEFICIENCY)
of Vitamin B12
typified by abnormally large
red blood cells.
Disturbs the nervous system
causing depression and
drowsiness.
37.
38. Conclusion
Free radical theory of aging is only concerned with all free radicals in
our body cause cumulative damage which would eventually lead to loss
of functionality, and ultimately death.
This theory is supported by a vast number of experiments and
observations .
This provide important view about free radicals.
There is no doubt that reactive free radicals such as hydroxyl and peroxy
radicals can damage biomolecules and their activities can be suppressed
by some antioxidants (free radical scavengers) such as α-tocopherol
(vitamin E) and ascorbic acid (vitamin C).
But this theory could not find differences between various free radicals
.However many free radicals help to regulate many functions in cells like
cell-cell signaling, killing of harmful bacteria , co-factors of enzymes.
Free radical theory of aging must be broaden and modify .