Masson Bastien, Le Ribeuz Hélène, Sabourin Jessica, Laubry Loann, Woodhouse Emily, Foster Richard, Ruchon Yann, Dutheil Mary, Boët Angèle, Ghigna Maria-Rosa, De Montpreville Vincent Thomas, Mercier Olaf, Beech David J, Benitah Jean-Pierre, Bailey Marc A, Humbert Marc, Montani David, Capuano Véronique, Antigny Fabrice
Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France (B.M., H.L.R., L.L.., Y.R, M.D, A.B., M.-R.G., M.H., D.M., V.C., F.A.).
INSERM UMR_S 999 « Hypertension pulmonaire: Physiopathologie et Innovation Thérapeutique », Hôpital Marie Lannelongue, Le Plessis-Robinson, France. B.M., H.L.R., L.L.., Y.R, M.D, A.B., M.-R.G., M.H., D.M., V.C., F.A.).
Circ Res. 2022 Oct 14;131(9):e102-e119. doi: 10.1161/CIRCRESAHA.122.321041. Epub 2022 Sep 27.
Pulmonary arterial hypertension (PAH) is characterized by progressive distal pulmonary artery (PA) obstruction, leading to right ventricular hypertrophy and failure. Exacerbated intracellular calcium (Ca) signaling contributes to abnormalities in PA smooth muscle cells (PASMCs), including aberrant proliferation, apoptosis resistance, exacerbated migration, and arterial contractility. Store-operated Ca entry is involved in Ca homeostasis in PASMCs, but its properties in PAH are unclear.
Using a combination of Ca imaging, molecular biology, in vitro, ex vivo, and in vivo approaches, we investigated the roles of the Orai1 SOC channel in PA remodeling in PAH and determined the consequences of pharmacological Orai1 inhibition in vivo using experimental models of pulmonary hypertension (PH).
Store-operated Ca entry and Orai1 mRNA and protein were increased in human PASMCs (hPASMCs) from patients with PAH (PAH-hPASMCs). We found that MEK1/2 (mitogen-activated protein kinase kinase 1/2), NFAT (nuclear factor of activated T cells), and NFκB (nuclear factor-kappa B) contribute to the upregulation of Orai1 expression in PAH-hPASMCs. Using small interfering RNA (siRNA) and Orai1 inhibitors, we found that Orai1 inhibition reduced store-operated Ca entry, mitochondrial Ca uptake, aberrant proliferation, apoptosis resistance, migration, and excessive calcineurin activity in PAH-hPASMCs. Orai1 inhibitors reduced agonist-evoked constriction in human PAs. In experimental rat models of PH evoked by chronic hypoxia, monocrotaline, or Sugen/hypoxia, administration of Orai1 inhibitors (N-{4-[3,5-bis(Trifluoromethyl)-1H-pyrazol-1-yl]phenyl}-4-methyl-1,2,3-thiadiazole-5-carboxamide [BTP2], 4-(2,5-dimethoxyphenyl)-N-[(pyridin-4-yl)methyl]aniline [JPIII], or 5J4) protected against PH.
In human PAH and experimental PH, Orai1 expression and activity are increased. Orai1 inhibition normalizes the PAH-hPASMCs phenotype and attenuates PH in rat models. These results suggest that Orai1 should be considered as a relevant therapeutic target for PAH.
肺动脉高压（PAH）的特征是远端肺动脉（PA）进行性阻塞，导致右心室肥厚和衰竭。细胞内钙（Ca）信号的加剧导致PA平滑肌细胞（PASMCs）出现异常，包括异常增殖、抗凋亡、迁移加剧和动脉收缩性改变。储存式Ca内流参与PASMCs的Ca稳态，但在PAH中的特性尚不清楚。
我们结合Ca成像、分子生物学、体外、离体和体内方法，研究了Orai1储存式Ca通道在PAH中PA重塑中的作用，并使用肺动脉高压（PH）实验模型确定了体内药理学抑制Orai1的后果。
PAH患者的人PASMCs（PAH-hPASMCs）中储存式Ca内流以及Orai1 mRNA和蛋白增加。我们发现，丝裂原活化蛋白激酶激酶1/2（MEK1/2）、活化T细胞核因子（NFAT）和核因子κB（NFκB）促成了PAH-hPASMCs中Orai1表达上调。使用小干扰RNA（siRNA）和Orai1抑制剂，我们发现抑制Orai1可减少PAH-hPASMCs中的储存式Ca内流、线粒体Ca摄取、异常增殖、抗凋亡、迁移及钙调神经磷酸酶活性过高。Orai1抑制剂可减少人PA中激动剂诱发的收缩。在慢性缺氧、野百合碱或Sugen/缺氧诱发的PH实验大鼠模型中，给予Orai1抑制剂（N-{4-[3,5-双（三氟甲基）-1H-吡唑-1-基]苯基}-4-甲基-1,2,3-噻二唑-5-甲酰胺[BTP2]、4-（2,5-二甲氧基苯基）-N-[(吡啶-4-基）甲基]苯胺[JPIII]或5J4）可预防PH。
在人类PAH和实验性PH中，Orai1表达和活性增加。抑制Orai1可使PAH-hPASMCs表型正常化，并减轻大鼠模型中的PH。这些结果表明，Orai1应被视为PAH的一个相关治疗靶点。
