This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: vitamins, Subject name: Biochemistry
Pellagra symptoms are aggravated if diet contains 
Select and explain. 
A. High amount of leucine, B. High amount of lysine, C. Low amount of leucine, D. Low amount of lysine
A: High amount of leucine
Answer: A: High amount of leucine 
Explanation: Pellagra symptoms are aggravated if diet contains high amount of leucine. Dietary deficiency of Tryptophan: Pellagra is seen among people whose staple diet is maize (South and Central America). In maize, niacin is present; but it is in a bound form, and is unavailable. Pellagra is also seen when staple diet is sorghum (jowar or guinea corn) as in Central and Western India. Sorghum contains leucine in high quantities. Leucine inhibits the QP enzyme, and so cannot be conveed to NAD+ (Leucine pellagra). Reference: Textbook of Biochemistry by D M Vasudevan, sixth edition pg no. 395, 396.