Browsing by Author "Wang, Ziyi"

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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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    Loss-of-function OGFRL1 variants identified in autosomal recessive cherubism families
    (Oxford University Press, 2024-04-09) Kittaka, Mizuho; Mizuno, Noriyoshi; Morino, Hiroyuki; Yoshimoto, Tetsuya; Zhu, Tianli; Liu, Sheng; Wang, Ziyi; Mayahara, Kotoe; Iio, Kyohei; Kondo, Kaori; Kondo, Toshio; Hayashi, Tatsuhide; Coghlan, Sarah; Teno, Yayoi; Doan, Andrew Anh Phung; Levitan, Marcus; Choi, Roy B.; Matsuda, Shinji; Ouhara, Kazuhisa; Wan, Jun; Cassidy, Annelise M.; Pelletier, Stephane; Nampoothiri, Sheela; Urtizberea, Andoni J.; Robling, Alexander G.; Ono, Mitsuaki; Kawakami, Hideshi; Reichenberger, Ernst J.; Ueki, Yasuyoshi; Anatomy, Cell Biology and Physiology, School of Medicine
    Cherubism (OMIM 118400) is a rare craniofacial disorder in children characterized by destructive jawbone expansion due to the growth of inflammatory fibrous lesions. Our previous studies have shown that gain-of-function mutations in SH3 domain-binding protein 2 (SH3BP2) are responsible for cherubism and that a knock-in mouse model for cherubism recapitulates the features of cherubism, such as increased osteoclast formation and jawbone destruction. To date, SH3BP2 is the only gene identified to be responsible for cherubism. Since not all patients clinically diagnosed with cherubism had mutations in SH3BP2, we hypothesized that there may be novel cherubism genes and that these genes may play a role in jawbone homeostasis. Here, using whole exome sequencing, we identified homozygous loss-of-function variants in the opioid growth factor receptor like 1 (OGFRL1) gene in 2 independent autosomal recessive cherubism families from Syria and India. The newly identified pathogenic homozygous variants were not reported in any variant databases, suggesting that OGFRL1 is a novel gene responsible for cherubism. Single cell analysis of mouse jawbone tissue revealed that Ogfrl1 is highly expressed in myeloid lineage cells. We generated OGFRL1 knockout mice and mice carrying the Syrian frameshift mutation to understand the in vivo role of OGFRL1. However, neither mouse model recapitulated human cherubism or the phenotypes exhibited by SH3BP2 cherubism mice under physiological and periodontitis conditions. Unlike bone marrow-derived M-CSF-dependent macrophages (BMMs) carrying the SH3BP2 cherubism mutation, BMMs lacking OGFRL1 or carrying the Syrian mutation showed no difference in TNF-ɑ mRNA induction by LPS or TNF-ɑ compared to WT BMMs. Osteoclast formation induced by RANKL was also comparable. These results suggest that the loss-of-function effects of OGFRL1 in humans differ from those in mice and highlight the fact that mice are not always an ideal model for studying rare craniofacial bone disorders