Browsing by Author "Makino, Ayako"

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    Endothelial eNAMPT drives EndMT and preclinical PH: rescue by an eNAMPT-neutralizing mAb
    (Wiley, 2021-11-12) Ahmed, Mohamed; Zaghloul, Nahla; Zimmerman, Prisca; Casanova, Nancy G.; Sun, Xiaoguang; Song, Jin H.; Reyes Hernon, Vivian; Sammani, Saad; Rischard, Franz; Rafikova, Olga; Rafikov, Ruslan; Makino, Ayako; Kempf, Carrie L.; Camp, Sara M.; Wang, Jian; Desai, Ankit A.; Lussier, Yves; Yuan, Jason X.-J.; Garcia, Joe G. N.; Medicine, School of Medicine
    Pharmacologic interventions to halt/reverse the vascular remodeling and right ventricular dysfunction in pulmonary arterial hypertension (PAH) remains an unmet need. We previously demonstrated extracellular nicotinamide phosphoribosyltransferase (eNAMPT) as a DAMP (damage-associated molecular pattern protein) contributing to PAH pathobiology via TLR4 ligation. We examined the role of endothelial cell (EC)-specific eNAMPT in experimental PH and an eNAMPT-neutralizing mAb as a therapeutic strategy to reverse established PH. Hemodynamic/echocardiographic measurements and tissue analyses were performed in Sprague Dawley rats exposed to 10% hypoxia/Sugen (three weeks) followed by return to normoxia and weekly intraperitoneal delivery of the eNAMPT mAb (1 mg/kg). WT C57BL/6J mice and conditional EC-cNAMPTec-/- mice were exposed to 10% hypoxia (three weeks). Biochemical and RNA sequencing studies were performed on rat PH lung tissues and human PAH PBMCs. Hypoxia/Sugen-exposed rats exhibited multiple indices of severe PH (right ventricular systolic pressure, Fulton index), including severe vascular remodeling, compared to control rats. PH severity indices and plasma levels of eNAMPT, IL-6, and TNF-α were all significantly attenuated by eNAMPT mAb neutralization. Compared to hypoxia-exposed WT mice, cNAMPTec-/- KO mice exhibited significantly reduced PH severity and evidence of EC to mesenchymal transition (EndMT). Finally, biochemical and RNAseq analyses revealed eNAMPT mAb-mediated rectification of dysregulated inflammatory signaling pathways (TLR/NF-κB, MAP kinase, Akt/mTOR) and EndMT in rat PH lung tissues and human PAH PBMCs. These studies underscore EC-derived eNAMPT as a key contributor to PAH pathobiology and support the eNAMPT/TLR4 inflammatory pathway as a highly druggable therapeutic target to reduce PH severity and reverse PAH.
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    Endothelial upregulation of mechanosensitive channel Piezo1 in pulmonary hypertension
    (American Physiological Society, 2021) Wang, Ziyi; Chen, Jiyuan; Babicheva, Aleksandra; Jain, Pritesh P.; Rodriguez, Marisela; Ayon, Ramon J.; Ravellette, Keeley S.; Wu, Linda; Balistrieri, Francesca; Tang, Haiyang; Wu, Xiaomin; Zhao, Tengteng; Black, Stephen M.; Desai, Ankit A.; Garcia, Joe G. N.; Sun, Xin; Shyy, John Y-J; Valdez-Jasso, Daniela; Thistlethwaite, Patricia A.; Makino, Ayako; Wang, Jian; Yuan, Jason X-J; Medicine, School of Medicine
    Piezo is a mechanosensitive cation channel responsible for stretch-mediated Ca2+ and Na+ influx in multiple types of cells. Little is known about the functional role of Piezo1 in the lung vasculature and its potential pathogenic role in pulmonary arterial hypertension (PAH). Pulmonary arterial endothelial cells (PAECs) are constantly under mechanic stretch and shear stress that are sufficient to activate Piezo channels. Here, we report that Piezo1 is significantly upregulated in PAECs from patients with idiopathic PAH and animals with experimental pulmonary hypertension (PH) compared with normal controls. Membrane stretch by decreasing extracellular osmotic pressure or by cyclic stretch (18% CS) increases Ca2+-dependent phosphorylation (p) of AKT and ERK, and subsequently upregulates expression of Notch ligands, Jagged1/2 (Jag-1 and Jag-2), and Delta like-4 (DLL4) in PAECs. siRNA-mediated downregulation of Piezo1 significantly inhibited the stretch-mediated pAKT increase and Jag-1 upregulation, whereas downregulation of AKT by siRNA markedly attenuated the stretch-mediated Jag-1 upregulation in human PAECs. Furthermore, the mRNA and protein expression level of Piezo1 in the isolated pulmonary artery, which mainly contains pulmonary arterial smooth muscle cells (PASMCs), from animals with severe PH was also significantly higher than that from control animals. Intraperitoneal injection of a Piezo1 channel blocker, GsMTx4, ameliorated experimental PH in mice. Taken together, our study suggests that membrane stretch-mediated Ca2+ influx through Piezo1 is an important trigger for pAKT-mediated upregulation of Jag-1 in PAECs. Upregulation of the mechanosensitive channel Piezo1 and the resultant increase in the Notch ligands (Jag-1/2 and DLL4) in PAECs may play a critical pathogenic role in the development of pulmonary vascular remodeling in PAH and PH.
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    Transcriptomic profiles in pulmonary arterial hypertension associate with disease severity and identify novel candidate genes
    (Sage, 2020-12-07) Romanoski, Casey E.; Qi, Xinshuai; Sangam, Shreya; Vanderpool, Rebecca R.; Stearman, Robert S.; Conklin, Austin; Gonzalez-Garay, Manuel; Rischard, Franz; Ayon, Ramon J.; Wang, Jian; Simonson, Tatum; Babicheva, Aleksandra; Shi, Yinan; Tang, Haiyang; Makino, Ayako; Kanthi, Yogendra; Geraci, Mark W.; Garcia, Joe G.N.; Yuan, Jason X.-J.; Desai, Ankit A.; Medicine, School of Medicine
    Using RNAseq, we identified a 61 gene-based circulating transcriptomic profile most correlated with four indices of pulmonary arterial hypertension severity. In an independent dataset, 13/61 (21%) genes were differentially expressed in lung tissues of pulmonary arterial hypertension cases versus controls, highlighting potentially novel candidate genes involved in pulmonary arterial hypertension development.