title: HIV-1/cocaine induced oxidative stress disrupts tight junction protein-1 in human pulmonary microvascular endothelial cells: role of Ras/ERK1/2 pathway.
abstract: Intravenous drug use (IVDU) is the major risk factor in the development of HIV-related pulmonary arterial hypertension (HRPAH); however, the pathogenesis of HRPAH in association with IVDU has yet to be characterized. Endothelial injury is considered to be an initiating factor for pulmonary vascular remodeling in animal models of PAH. Our previous study shows that simultaneous exposure to HIV-Trans-activator of transcription (Tat) and cocaine exacerbates both disruption of tight junction proteins and permeability of human pulmonary artery endothelial cells compared with either treatment alone. We here now demonstrate that this HIV-Tat and cocaine mediated endothelial dysfunction accompanies with increase in hydrogen peroxide and superoxide radicals generation and involves redox sensitive signaling pathway. Pretreatment with antioxidant cocktail attenuated the cocaine and Tat mediated disassembly of Zonula Occludens (ZO)-1 and enhancement of endothelial monolayer permeability. Furthermore, inhibition of NADPH oxidase by apocynin or siRNA-mediated knockdown of gp-91(phox) abolished the Tat/cocaine-induced reactive oxygen species (ROS) production, suggesting the NADPH oxidase mediated generation of oxidative radicals. In addition, ROS dependent activation of Ras and ERK1/2 Kinase was observed to be mediating the TJP-1 disassembly, and endothelial dysfunction in response to cocaine and Tat exposure. In conclusion, our findings demonstrate that Tat/cocaine -mediated production of ROS activate Ras/Raf/ERK1/2 pathway that contributes to disruption of tight junction protein leading to pulmonary endothelial dysfunction associated with pulmonary vascular remodeling.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Pranjali
authors.initials: P
authors.lastname: Dalvi
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Kun
authors.initials: K
authors.lastname: Wang
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Joel
authors.initials: J
authors.lastname: Mermis
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Ruoxi
authors.initials: R
authors.lastname: Zeng
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Miles
authors.initials: M
authors.lastname: Sanderson
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Sara
authors.initials: S
authors.lastname: Johnson
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Yuqiao
authors.initials: Y
authors.lastname: Dai
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Garima
authors.initials: G
authors.lastname: Sharma
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Amy O'Brien
authors.initials: AO
authors.lastname: Ladner
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America ; Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
authors.forename: Navneet K
authors.initials: NK
authors.lastname: Dhillon
mesh_terms: D000975:Antioxidants / Q000494:pharmacology; D002199:Capillary Permeability / Q000187:drug effects / Q000235:genetics; D003042:Cocaine / Q000494:pharmacology*; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism* / Q000821:virology; D055785:Gene Knockdown Techniques; D015497:HIV-1 / Q000378:metabolism*; D006801:Humans; D008168:Lung / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism / Q000821:virology; D020935:MAP Kinase Signaling System; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D011485:Protein Binding; D016283:Proto-Oncogene Proteins p21(ras) / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D017480:Receptors, sigma / Q000378:metabolism; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism; D062826:Zonula Occludens-1 Protein / Q000378:metabolism*; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000378:metabolism / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D017480:Receptors, sigma; D062826:Zonula Occludens-1 Protein; D054322:tat Gene Products, Human Immunodeficiency Virus; D019255:NADPH Oxidases; D040301:Vascular Endothelial Growth Factor Receptor-2; D016283:Proto-Oncogene Proteins p21(ras); D003042:Cocaine