Biochem Exam 2 Flashcards
PDH Deficiency
Causes chronic lactic acidosis in kids (fatal)
Neuro probs
Thiamine (B1) Deficiency
Alcoholics, poor diet, nausea, constipation, appetite loss
Beri-beri
Advanced deficiency syndromes
Alcoholics, Wernicke-Korsakoff syndrome
confusion, ataxia, loss of eye coordination
Beri-beri
Dry: neuromuscular, no fluid retention
Wet: peripheral edema, cardiac failure
Thiamine deficiency affects transketolase of PPP
Also affects PDH, alpha-KGDH (alcohol abuse)
CAC enzyme defects
lactic acidosis
Pyruvate carboxylase deficiency
lactic acidosis
Ketosis/ketoacidosis
High ketone bodies, excessive acetyl-CoA
Starvation (low carb/Atkins diets) => ketosis
DM => ketoacidosis
Arsenate
looks like phosphate and binds to form 3-phosphoglycerate using phosphoglycerate kinase but no energy output means cells starve
Essential fructosuria
no fructokinase, no uptake, benign
Hereditary Fructose Intolerance
Deficient in aldolase B so fructose-P accumulates in liver
Phosphate depletes, then can’t break down glycogen so it accumulates
Solution: avoid fructose and sucrose
Galactosemia
Gal-P accumulates in liver/CNS/kidney causing liver failure
Galactose-1-phosphate uridyl transferase deficiency s most common/severe
Galactokinase deficiency
UDP-gal-epimerase deficiency
G6PD deficiency
Lowered PPP activity -> low NADPH levels -> deprive RBCs of antioxidants
Pt sensitive to H2O2 and Fava beans
Fructose-1,6-Bisphosphatase Deficiency
Fasting hypoglycemia and metabolic acidosis
High lactate/pyruvate/ketones
Low glucose
Pompe Disease
Glycogen buildup, GSD II
Glycogen phosphorylase deficiency
Cannot break down glycogen
Muscle: GSD V = McArdle
Liver: GSD VI = Hers
McArdle
Muscle glycogen phosphorylase deficiency; cannot breakdown glycogen
GSD V
Hers
Liver glycogen phosphorylase deficiency; cannot breakdown glycogen
GSD VI
GSD III
Cori
Problem with debranching enzyme
No phosphorylase
GSD I
Von Gierke
G6 phosphatase cannot form glucose from Glu-6P
GSD II
Pompe
Alpha-glucosidase cannot make glucose from lysosome/glycogen
Mucopolysaccharidoses
problem with degradation of proteoglycans so they accumulate in lysosomes over years
Hunter’s
Defective Iduronate synthase causing accumulation of dermatan sulfate and heparin sulfate
Causes skeleton abnormalities and MR