This is a lecture class presentation for the students of Medical Biochemistry on the water-soluble vitamin - vitamin B1, its dietary sources, co-enzyme forms, chemical structure, functions, deficiency diseases, and their prevention and treatments.

1. Thiamine (Vitamin B1)
Anti beriberi
or
Anti neuritic
vitamin

2. Thiamine or vitamin B1
is a water soluble vitamin
essential for
glucose metabolism and
healthy nerve,
muscle &
heart function.

3. Thiamine (Vitamin B1)
Dietary Source Functions
Disorders Treatment

4. Chemistry of Vitamin B1

5. Chemistry:
Structure of thiamine

6. Active form: Thiamine pyrophosphate (TPP)
TPP is formed by the transfer of a
pyrophosphate group from
adenosine triphosphate (ATP)
to thiamine.

7. RDA

8. RDA:
1 -1.5 mg/ day - in adult
0.7 -1.2 mg/ day - in children
2 mg/ day - in pregnancy
& lactation

9. The requirement increases in
pregnancy & lactation,
elderly and
in alcoholics.

10. Dietary sources

11. Dietary sources:
1. Plant source:
Whole grain cereals (unpolished rice,
bran of cereals), pulses, oil seeds, nuts &
yeast
2. Animal source:
Meat (Pork), liver, heart, kidney, milk

12. Reactions dependent
on TPP

13. Phases of catabolism

14. Glycolysis
Glucose

15. TPP
TPP
α- Ketogluterate
dehydrogenase
Pyruvate
CO2
Pyruvate
dehydrogenase

16. Pentose phosphate pathway

18. Biomedical functions:
1. Helps in glucose oxidation by acting as
coenzyme for oxidative decarboxylation
reaction.
Pyruvate Acetyl Co A
α- Ketogluterate Succinyl Co A
TPP
pyruvate dehydrogenase
α- Ketoglutarate dehydrogenase
TPP
CO2
CO2

19. 2. Helps in glucose oxidation through hexose
monophosphate shunt by acting as
coenzyme for transketolase.

20. 3. The branched chain a-keto acid
dehydrogenase catalyses the
oxidative decarboxylation of branched chain
amino acids to the respective keto acids also
requires TPP.

21. 4. TPP plays an important role in the
nerve impulse transmission .
TPP is required for
acetylcholine synthesis
and
ion translocation of
neural tissue.

22. Deficiency disorsers

23. Deficiency disorders:
1. Beriberi
2. Wernicke – Korsakoff syndrome
3. Korsakoff psychosis

24. 1. Beriberi:
This is a severe thiamine deficiency
syndrome seen in populations consuming
exclusively polished rice or other highly
refined foods such as white flour.

25. Types:
1. Infantile beriberi:
This is seen in infants born to mothers
suffering from thiamine deficiency.

26. Clinical features:
Tachycardia
Vomiting
Convulsion
Abdominal colic
Death may occur due to cardiac failure

27. 2. Adult beriberi:
Adult beriberi is of two types-
a. Dry beriberi
b. Wet beriberi

28. a. Dry beriberi:
It is characterized by-
peripheral neuropathy
Dry skin
Muscular degeneration
Weakness

29. Neurological manifestations
Dry Beriberi
Peripheral neuritis
Severe leg pain
Paralysis

30. b. Wet beriberi:
It is characterized by-
Oedema of face , leg , & ascitis
Tachycardia
Breathlessness
Palpitation
Rise of systolic blood pressure
Cardiac failure

31. Wet Beriberi
Edema
Difficulty in breathing
Heart failure

32. 2. Wernicke - Korsakoff syndrome:
In the United States, thiamine deficiency,
seen primarily in association with chronic
alcoholism ,is due to dietary insufficiency
or impaired intestinal absorption of the
vitamin.

33. Wernicke - Korsakoff syndrome is a
thiamin deficiency state characterized by
apathy, confusion, loss of memory, ataxia &
a rhythmic to-and-fro motion of the eyeballs
(nystagmus).

34. Memory problems and hallucinations
also occurs with
Korsakoff dementia.
Hallucination
Dementia

35. The neurologic consequences of
Wernicke - Korsakoff syndrome
can be treated with
thiamine supplementation.

36. Treatment of of Wernicke -
Korsakoff syndrome
B1 supplementation
Dietary intake No alcohol