Question

Chronic alcoholism is a common contributor to thiamin deficiency which can cause lactic acid acidosis. Briefly explain.

Answer 1

Chronic alcoholism causes thiamine deficiency by

i. Inhibiting nutritional intake

ii. Decreased absorption of thiamine from the intestine

iii. Reduced uptake into the cells

iv. Impaired utilization of thiamine in the cells

Thiamine plays an important role in carbohydrate metabolism. It is a component of the cofactor TPP.

Pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase are thiamine-dependent enzymes.

If thiamine levels are low, pyruvate is not converted to acetyl CoA by PDH and YCA cycle can not function efficiently.

This results in the increased conversion of pyruvate to lactate even in the presence of oxygen. Accumulation of lactate in the tissues leads to Lactic Acidosis.