Monocrotaline Induces Endothelial Injury and Pulmonary Hypertension by Targeting the Extracellular Calcium-Sensing Receptor.
BACKGROUND
Monocrotaline has been widely used to establish an animal model of pulmonary hypertension. The molecular target underlying monocrotaline-induced pulmonary artery endothelial injury and pulmonary hypertension remains unknown. The extracellular calcium-sensing receptor (CaSR) and particularly its extracellular domain hold the potential structural basis for monocrotaline to bind. This study aimed to reveal whether monocrotaline induces pulmonary hypertension by targeting the CaSR.


RESULTS
Nuclear magnetic resonance screening through WaterLOGSY (water ligand-observed gradient spectroscopy) and saturation transfer difference on protein preparation demonstrated the binding of monocrotaline to the CaSR. Immunocytochemical staining showed colocalization of monocrotaline with the CaSR in cultured pulmonary artery endothelial cells. Cellular thermal shift assay further verified the binding of monocrotaline to the CaSR in pulmonary arteries from monocrotaline-injected rats. Monocrotaline enhanced the assembly of CaSR, triggered the mobilization of calcium signaling, and damaged pulmonary artery endothelial cells in a CaSR-dependent manner. Finally, monocrotaline-induced pulmonary hypertension in rats was significantly attenuated or abolished by the inhibitor, the general or lung knockdown or knockout of CaSR.


CONCLUSIONS
Monocrotaline aggregates on and activates the CaSR of pulmonary artery endothelial cells to trigger endothelial damage and, ultimately, induces pulmonary hypertension.
Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Rui
R
Xiao
Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Department of Respiratory Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Yuan
Y
Su
Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Tian
T
Feng
Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Mengxiang
M
Sun
Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Bingxun
B
Liu
Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Department of Pathology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Jiwei
J
Zhang
Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Department of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Yankai
Y
Lu
Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Department of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Jiansha
J
Li
Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Department of Respiratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Tao
T
Wang
Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China qinghuaa@mails.tjmu.edu.cn 16654396@qq.com.|Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.
Liping
L
Zhu
Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China qinghuaa@mails.tjmu.edu.cn 16654396@qq.com.|Key Laboratory of Pulmonary Diseases of Ministry of Health, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology (HUST), Wuhan, China.|Key Laboratory of Molecular Biophysics of the Ministry of Education, Huazhong University of Science and Technology (HUST), Wuhan, China.
Qinghua
Q
Hu
D000818:Animals; D002478:Cells, Cultured; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D020022:Genetic Predisposition to Disease; D006976:Hypertension, Pulmonary / Q000139:chemically induced* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008297:Male; D016686:Monocrotaline / Q000378:metabolism / Q000633:toxicity*; D019906:Nuclear Magnetic Resonance, Biomolecular; D010281:Parathyroid Hormone / Q000172:deficiency / Q000235:genetics; D010641:Phenotype; D011485:Protein Binding; D011651:Pulmonary Artery / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D034622:RNA Interference; D017207:Rats, Sprague-Dawley; D055647:Rats, Transgenic; D044169:Receptors, Calcium-Sensing / Q000819:agonists* / Q000172:deficiency / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects; D014162:Transfection
D010281:Parathyroid Hormone; D044169:Receptors, Calcium-Sensing; C473605:extracellular calcium cation-sensing receptor, rat; D016686:Monocrotaline
endothelial injury; extracellular calcium–sensing receptor; intracellular calcium; monocrotaline; pulmonary hypertension