MAPK8 and pulmonary arterial hypertension: Concurrently, Akt activation enhances aerobic glycolysis and glycolysis-dependent lipogenesis.180,374,375 In vitro stimulation of bovine PASMCs with 5-HT demonstrated that activated JNK enhances Cyclin D expression by activating the Akt pathway, ultimately leading to increased cell proliferation.374 JNK plays a central role in metabolic reprogramming in PASMCs affected by PAH.