Formative 2

• -          Alcohol also delays glycogenolysis leading to longer periods of hypoglycemia with no glycogen breakdown

  -          Chronic alcohol ingestion can also lead to deficiency in vitamin B1 and other B vitamins, which are required for the enzymatic activity of enzymes involved in glucose metabolism
• -          Alcohol affects the body’s glucose metabobolism by blocking synthesis of glucose through gluconeogenesis. Alcohol’s interference with this process causes hypoglycemia

  -          Alcohol dehydrogenase produces NADH when alcohol is broken down, giving the body a false sense of energy and blocking gluconeogenesis

  -          Alcohol increases the body’s sensitivity to insulin, glucose intake in cells is higher after a meal, causing a quick “crash” in blood sugar as too much glucose is taken in by cells leading to hypoglycemia
• What are the necessary vitamins for the TCA cycle?

  -          Vitamin B1 is a coenzyme for the pyruvate and alpha keto-glutarate dehydrogenase enzyme complexes in the form of thiamine pyrophosphate

  -          Pantothenic acid (vitamin B5) is also a component of coenzyme A, which is used to synthesize acetyl CoA and succinyl CoA

  -          Vitamin B2 is a coenzyme for the succinate and alpha keto-glutarate dehydrogenase enzyme complexes in the form of FAD

  -          Vitamin B3 is a coenzyme for the malate, isocitrate and alpha keto-glutarate dehydrogenase enzyme complexes in the form of NAD
• Why is Thiamine deficiency clinically important?

  -          Dietary thiamin is used for the synthesis of its coenzyme thiamine pyrophosphate

  -          TPP is required for the metabolism of glucose and branched-chain amino acids

  -          TPP is involved in the decarboxylation of alpha keto-acids

  -          TPP is a cofactor for pyruvate dehydrogenase and a-ketoglutarate dehydrogenase in the TCA cycle
• -          TPP is also the cofactor for transketolase in the Pentose Phosphate Pathway

  -          Many major catabolic, energy producing pathways are dependant on TPP – thus causing muscle weakness

  -          TPP also assists in DNA and RNA production as well as synthesis of neurotransmitters – thus causing amnesia

  -          Lactate and pyruvate accumulate in people with thiamine deficiency as pyruvate dehydrogenase requires TPP