PFKFB2 and pulmonary arterial hypertension: Despite a decrease in glycolytic key intermediates and enzymes, PFKFB2, an enzyme responsible for irreversibly converting fructose-6-phosphate (F6P) to fructose-1,6-bisphosphate (1,6-FBP) in the committed step of glycolysis was increased, perhaps in response to increased F6P levels, yet there was a decrease in the product fructose 1,6-bisphosphate in PAH lungs.