These slides containing a brief introduction of thiamine including diseases caused by its deficiency.

1. Thiamine
(Vitamin B1)
Komal Soni
M.sc.(Deptt. Of Nutrition Biology)
2nd Semester
Central University of Haryana
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2. Contents
 Introduction
 Chemistry of Thiamine
 Functions
 Sources
 Absorption
 Transportation
 Storage
 Excretion
 Deficiency
 Common symptoms of thiamine deficiency
 Some researches on Thiamine
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3. Introduction
 Thiamine is also known as vitamin B1, anti Beri-Beri
vitamin.
 Discovered by Christian Eijkman in 1897.
 Water –soluble.
 Needed on daily basis.
 Non-toxic.
 Plays critical role in energy production.
 Required as co-enzyme.
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4. Chemistry of Thiamine
 White, water soluble crystalline solid.
 It’s an organosulphur compound having formula
C12H17ON4S
 Structure consists of an aminopyrimidine & thiazolium ring
linked by a methylene bridge.
 Stable at acidic pH, destroys at alkaline pH.
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5. Functions
 Precursor of co-enzyme TPP(Thiamine pyro
phosphate).
 Stimulate appetite.
 Normal nerve function by providing energy.
 Synthesize & regulate neurotransmitters (myelin
sheath production)
 Cure Beri-Beri.
 Proper function of heart muscles.
 Formation of RBCs
 Healthy mucus membrane.
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6. Sources
Plant sources
 Vegetables
 Cereals
 Pulses
 Nuts
 Oil seeds
 Orange & tomato juices
Animal sources
 Milk
 Pork
 Egg
 Poultry
 Fish
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8. Absorption
 Most of the absorption of thiamine occurs in the
jejunum & ileum of small intestine.
 If thiamine is consumed in small amounts, is absorbed
by sodium dependent active transport mechanism.
 If large amounts are consumed, passive diffusion takes
place.
 Thiamine as TPP within food must be dephosphorylated
to thiamine before absorption.
 TPP is then reformed from thiamine & phosphate
within cells whenever required.
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9. Thiamine Pyrophosphate
Thiamine Monophosphate
Thiamine
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Thiamine Pyrophosphatase
Thiamine Monophosphatase
ThiaminePyrophosphokinase

10. Transportation
 Thiamine is transported via blood.
 Majority of thiamine is bound to protein Albumin.
 Approx. 90% of total thiamine in blood is in
erythrocytes.
 Thiamine-Binding Protein (TBP) is important for tissue
distribution of thiamine.
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11. Storage
 Very low Thiamine is stored in liver & erythrocytes in
the form of TPP.
 When circulating thiamine levels decrease , the stored
TPP TMP Thiamine
Released into the circulation
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12. Excretion
 Excess thiamine is excreted in urine.
 Mainly excreted as thiamine & TMP.
Other acid metabolites are:
 2-methyl-4-amino-5-pyrimidine carboxylic acid
 4-methyl-thiazole-5-acetic acid
 Thiamine acetic acid
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13. Deficiency
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 When healthy individuals are deprived of Thiamine,
thiamine stores are depleted within one month.
 Within a week after thiamine intake stops :
tachycardia, weakness, decreased tendon reflexes,
some develops diseases.

14. Deficiency Diseases
B1
Deficiency
Wet Beri -
Beri
Dry Beri-
Beri
Infantile
Beri- Beri
Wernicke–
Korsakoff
Syndrome
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15. Wet Beri- Beri
 Affects cardiovascular system.
 Pathophysiology :
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vasodilat
ation
Left
ventricle do
not pump
blood
effectively
Blood
backs up
in left
atrium
Pulmonary
veins
Pulmonary
capillaries
Pulmonary
hypertension
Watercomes
into
interstitial
space
Pulmonary
edema
Less
oxygen

16. Symptoms:
 Dyspnea
 Orthopnea
 Increased heart rate
 Pulmonary edema
 Swelling in legs
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17. Dry Beri- Beri
 Affects central nervous system.
 Causes peripheral neuropathy with myelin
degeneration.
Thiamine helps in myelin sheath production.
Symptoms:
 Difficulty in walking
 Paralysis in lower legs
 Mental confusion
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19. Infantile Beri- Beri
 It occurs in infants between 2-5 months of age( who are
fed only breast milk) & whose mothers are thiamine
deficient.
 The affected baby develops cyanosis ( skin turns blue
due to lack of oxygen), tachycardia, vomiting &
convulsions.
 Cyanosis becomes visible when there is >3-5g/dl of
deoxygenated hemoglobin.
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Cyanosis

21. Wernicke- Korsakoff Syndrome
 Consumption of excessive alcohol can lead to
malnutrition & poor absorption of thiamine.
 Sometimes reason may be Bariatric surgery
(Gastrectomy).
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Wernicke’s encephalopathy Korsakoff’s syndrome
 Language problem
 Unusual eye movements
 Mental confusion
 Memory loss
 Impaired ability to learn
 Confabulation( making up
stories)

22. Common symptoms of thiamine deficiency
 Tachycardia
 Numbness in legs & hands
 Edema
 Weakness
 Mental confusion
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23. Some researches on Thiamine
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Helps in treatment of Lactic Acidosis

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Vascular complications in Diabetes

25.  In diabetic patient, endothelial glycocalyx layer damages
so can’t restrict albumin excretion.
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Thiamine could reverse early kidney diseases
in Diabetes

26.  Consuming high thiamine (300mg/day) will reduce the
excretion of albumin.
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27.  Consumption of Thiamine fortified Fish Sauce by
pregnant women for 6 months – reduces chances of
infantile beri -beri.
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Thiamine fortified Fish Sauce help fight Infantile
Beri-Beri in Southeast Asia.

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