Thiamin

维生素 B1

Place · Level 3

糖进入线粒体的门票 · 高耗能神经和心脏最怕它缺

Connected to · 2

cofactor · 1

α-Lipoic Acid
PDH/KGDH/BCKD all carry TPP (B1) and lipoyl (ALA): B1 cleaves the C-C bond, lipoyl carries reducing equivalents.

depletes · 1

Alcohol Metabolism
Chronic alcohol → ↓thiamine absorption (gut + liver) + ↑demand (ALDH consumes NAD → more cofactors needed). Alcoholic Wernicke-Korsakoff is the most severe B1 deficiency consequence. Classic triad: ophthalmoplegia + ataxia + confusion. B1 must be given before glucose infusion (glucose accelerates depletion → acute Wernicke).

TPP coenzyme

Stop 1/5

TPP 辅酶

Once B1 enters the body, it's converted to thiamin pyrophosphate (TPP). TPP isn't fuel — it's an indispensable tool-head for several key enzymes.

The three most important targets:

1. Pyruvate dehydrogenase complex (PDC): converts pyruvate from glycolysis into acetyl-CoA, which enters the cycle. When B1 is deficient, this step jams — carbon from glucose can't enter mitochondrial oxidation
2. Alpha-ketoglutarate dehydrogenase: a step in the TCA cycle, also requiring TPP
3. Transketolase: in the pentose phosphate pathway, linked to nucleotide synthesis and NADPH production

Read story Open mechanism

Educational content, not medical advice — consult a clinician.

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Thiamin

维生素 B1

Place · Level 3

糖进入线粒体的门票 · 高耗能神经和心脏最怕它缺

Connected to · 2

cofactor · 1

α-Lipoic Acid
PDH/KGDH/BCKD all carry TPP (B1) and lipoyl (ALA): B1 cleaves the C-C bond, lipoyl carries reducing equivalents.

depletes · 1

Alcohol Metabolism
Chronic alcohol → ↓thiamine absorption (gut + liver) + ↑demand (ALDH consumes NAD → more cofactors needed). Alcoholic Wernicke-Korsakoff is the most severe B1 deficiency consequence. Classic triad: ophthalmoplegia + ataxia + confusion. B1 must be given before glucose infusion (glucose accelerates depletion → acute Wernicke).

TPP coenzyme

Stop 1/5

TPP 辅酶

Once B1 enters the body, it's converted to thiamin pyrophosphate (TPP). TPP isn't fuel — it's an indispensable tool-head for several key enzymes.

The three most important targets:

1. Pyruvate dehydrogenase complex (PDC): converts pyruvate from glycolysis into acetyl-CoA, which enters the cycle. When B1 is deficient, this step jams — carbon from glucose can't enter mitochondrial oxidation
2. Alpha-ketoglutarate dehydrogenase: a step in the TCA cycle, also requiring TPP
3. Transketolase: in the pentose phosphate pathway, linked to nucleotide synthesis and NADPH production

Read story Open mechanism

Educational content, not medical advice — consult a clinician.