VITAMIN E

2. VITAMIN E
Dr. Muhammad Sarfraz
M.B.B.S., M.Phil.(Pharmacology)
Senior Demonstrator
Quaid-e-Azam Medical College
Bahawalpur, pakistan.
2

3. Vitamin E
3

4. Vitamin E
• GENERIC TERM
• used for a
• Group Of Chemically-similar
Compounds Sharing
• Tocopherol
• And
• Tocotrienol
4

5. The primary function of
vitamin E
5

6. ANTIOXIDANT
preventing
Nonenzymic Oxidation
Of
Cell Components
by
Molecular Oxygen
And Free Radicals
example
Polyunsaturated Fatty Acids
6

7. Function of vitamin E
CELL SIGNALING
7

8. Vitamin E
FAT-SOLUBLE vitamin
• ANTI-OXIDANT
protect
• AGAINST LIPID
PEROXIDATION
(Which Could Contribute To
Cell Membrane Weakness)
8

9. Vitamin E
• Chain-breaking antioxidant
• Inactivates free radicles
• Protects
low-density lipoproteins (LDLs)
and
polyunsaturated fatty acids
in membranes from oxidation 9

10. Vitamin E
• Free radicals
Super oxide O-2
Hydroxyl ionns OH
Nitric oxide NO
Cause Oxidative Damage And
Cell Death
10

11. Vitamin E
Prevent Cell Damage By
Binding To The Free
Radical And Neutralising
Its Unpaired Electron
11

12. 12

13. 13

14. 14

15. © 2008 Thomson - Wadsworth

16. α-TOCOPHEROL
Most Biologically Active Form
16

17. Tocotrienol
17

18. Chemistry
• EQUIPPED TO PERFORM A
UNIQUE FUNCTION
• CAN INTERRUPT FREE
RADICAL CHAIN
REACTIONS
BY CAPTURING THE FREE
RADICAL
18

19. Chemistry
FREE HYDROXYL GROUP
ON
THE AROMATIC RING
IS RESPONSIBLE FOR THE
ANTIOXIDANT PROPERTIES.
19

20. Tocotrienol
20

21. Chemistry
•Reacting with the
Lipid Peroxide
Radicals
• formed by
peroxidation of
polyunsaturated fatty
acids 21

22. Chemistry
Hydrogen
DONATED
To
Free Radical
Resulting In A Relatively Stable
Free Radical Form Of The
Vitamin
22

23. Chemistry
Tocopheroxyl Radical
Relatively
Unreactive
23

24. Chemistry
Tocopheroxyl Radical
Reduced Back
To
Tocopherol
by reaction with
vitamin C
24

25. VITAMEN “E”
Absorption From GIT
25

26. Absorption
Vitamin can only be
absorbed
after
being cleaved
by
Esterases
in the intestine
26

27. Transport
•First Absorbed Into
The Hepatic Portal
Vein
After Being packaged
Inside
Chylomicron 27

28. 28

29. Absorption
IN THE LIVER
Packaged into
VLDL
29

30. Vit E
No Specific Carrier
Protein
For
Vitamin E
30

31. Absorption
• VLDLs
released into the
bloodstream
31

32. 32

33. •Without the protective
barrier of the lipoproteins
•Vit E will be exposed to
the oxidative radicals
circulating through the
blood
33

34. Vit E
Prevents
The
Oxidation
Of
LDL 34

35. Oxidized LDL
• An Important Factor In
Atherogenesis
• Adequate Amounts Of
Vitamin E
Help Protect
Against Atherosclerosis
35

36. 36

37. Absorption
Alpha-tocotrienol
Appears To Be Better
Absorbed Than The
Other
Tocopherols
37

38. Tissue Uptake
Adipose Tissue
Adrenal Gland
Having The Highest
Levels
38

39. Tissue Uptake
Stored In Tissue
For
Long Periods Of Time
(Years)
Due To Its Exceedingly
Slow Turnover Rate 39

40. SOURCES OF VITAMIN E
40

41. •Vegetable oils
are rich sources of
vitamin E
41

42. • Liver and eggs
contain moderate
amounts
• RDA
for
α-tocopherol
15 mg for Adults 42

43. The vitamin E
requirement
increases as the
intake of
polyunsaturated fatty
acid increases
43

44. Sources of Vitamin E
Nuts
Seeds
Vegetable Oils
Green Leafy Vegetables
Wheat Germ Oil
Mangoes
Sweet Potato etc. 44

45. 45

46. 46

47. FUNCTIONS
• As an antioxidant
47

48. functions
• It Protects The Red Blood
Cells Against Hemolysis.
• Reduces The Risk Of
Atherosclerosis.
48

49. functions
The Body Needs
Vitamin E To Help
Keep The Immune
System Strong
Against Viruses And
Bacteria 49

50. functions
Cells Use Vitamin E To
Interact With Each
Other And Carry Out
Many Important
Functions
(Cell Signaling)
50

51. 51

52. Vitamin E deficiency is
almost entirely
restricted to premature
infants
52

53. Vitamin E Deficiency
• Dietary Deficiency Of
Vitamin E In Humans Is
Unknown
53

54. Vitamin E Deficiency
• Patients With
• Severe Fat Malabsorption
Cystic Fibrosis
Chronic Liver Disease
Suffer Deficiency Because
They Are Unable To Absorb
The Vitamin Or Transport It54

55. Vitamin E Deficiency
• Exhibiting Nerve And
Muscle Membrane
Damage
55

56. Vitamin E Deficiency
• Premature Infants
Inadequate Reserves Of The
Vitamin
• Erythrocyte Membranes
Fragile
Peroxidation
Leading To Hemolytic Anemia56

57. Vitamin E Deficiency
Retrolental fibroplasia
57

58. TOXICITY
• Least toxic
of the
fat-soluble vitamins
• No toxicity has been
observed at doses of
300 mg/day.
58