This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: TCA Cycle, Subject name: Biochemistry
[{'content': 'Which of the following intermediates of TCA cycle is depleted in Type-I Diabetes mellitus to suppress TCA cycle? \nSelect and explain. \nA. Succinate, B. Malate, C. a-Ketoglutarate, D. Oxaloacetate', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Remember diabetic condition is similar to fasting/starvation (catabolic state) as body tissues does not get enough glucose. Hence gluconeogenesis and lipolysis is upregulated. TCA suppression in diabetes occurs due to following reasons: Oxaloacetate is used up for gluconeogenesis, which is not available for TCA. Excess lipolysis leads to increased beta oxidation of fatty acids which lead to the formation of excess NADH , which fuher depletes NAD. This suppresses TCA. Acetyl CoA is diveed to ketone body synthesis.', 'role': 'assistant'}]