title: KMUP-1 inhibits pulmonary artery proliferation by targeting serotonin receptors/transporter and NO synthase, inactivating RhoA and suppressing AKT/ERK phosphorylation.
abstract: KMUP-1 inhibits monocrotaline (MCT)-induced pulmonary artery (PA) proliferation by targeting serotonin (5-HT) receptors, inactivating RhoA and reducing phosphorylation of AKT/ERK. In MCT-treated rats, KMUP-1 f (5 mg/kg p.o.; 1mg/kg i.p.x 21 days) decreased proliferation (PCNA-positive) cells and 5-HTT-expression in lung and 5-HT levels in plasma. In isolated PA, KMUP-1 and simvastatin (0.1-100 μM) inhibited 5-HT (10 μM)-induced PA constriction. l-NAME-pretreatment reduced KMUP-1-induced relaxation. In pulmonary arterial smooth muscle cells (PASMCs), KMUP-1 (1-100 μM) and simvastatin (10 μM) inhibited 5-HT-induced cell migration and proliferation and KMUP-1 (1-100 μM) inhibited 5-HT-induced Ca²+ influx. Similar to Y27632, KMUP-1 (1-100 μM) inhibited 5-HT-induced RhoA/ROCK expression, while KMUP-1, Y27632 and simvastatin at 10 μM inhibited 5-HT-induced 5-HTT expression and KMUP-1 inhibited 5-HT-induced phosphorylation of AKT and ERK1/2 in PASMCs. In human pulmonary arterial endothelial cell (HPAEC), KMUP-1 (1-100 μM) increased the expression of eNOS and 5-HT(2B) and also at 10 μM augmented eNOS expression and production of nitric oxide (NO) in 5-HT-treated HPAEC. In radioligand binding, the IC₅₀/K(i) values of KMUP-1 for 5-HT(2A), 5-HT(2B) and 5-HT(2C) receptors were 0.34/0.0971, 0.04/0.0254, and 0.408/0.214 μM respectively. In conclusion, KMUP-1 inhibits MCT-induced PA proliferation by binding to 5-HT(2A), 5-HT(2B) and 5-HT(2C) receptors, increasing endothelial eNOS/5-HT(2B) receptor expression and NO release and inhibiting 5-HTT/RhoA/ROCK expression and AKT/ERK phosphorylation. KMUP-1 is suggested to be useful in the treatment of 5-HT-induced pulmonary artery proliferation.
authors.affiliation: Graduate Institute of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Hui-Hsuan
authors.initials: HH
authors.lastname: Chung
authors.forename: Zen-Kong
authors.initials: ZK
authors.lastname: Dai
authors.forename: Bin-Nan
authors.initials: BN
authors.lastname: Wu
authors.forename: Jwu-Lai
authors.initials: JL
authors.lastname: Yeh
authors.forename: Chee-Yin
authors.initials: CY
authors.lastname: Chai
authors.forename: Koung-Shing
authors.initials: KS
authors.lastname: Chu
authors.forename: Chung-Pin
authors.initials: CP
authors.lastname: Liu
authors.forename: Ing-Jun
authors.initials: IJ
authors.lastname: Chen
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D016686:Monocrotaline; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D010766:Phosphorylation; D010880:Piperidines / Q000494:pharmacology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D011651:Pulmonary Artery / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011985:Receptors, Serotonin / Q000378:metabolism*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D014970:Xanthines / Q000494:pharmacology*; D054460:rho-Associated Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D010880:Piperidines; D011985:Receptors, Serotonin; D050486:Serotonin Plasma Membrane Transport Proteins; D014970:Xanthines; C439304:KMUP 1; D016686:Monocrotaline; D019001:Nitric Oxide Synthase; D051057:Proto-Oncogene Proteins c-akt; D054460:rho-Associated Kinases; D048049:Extracellular Signal-Regulated MAP Kinases