Medical Toxicology Commons^™

Neprilysin Is A Mediator Of Alternative Renin-Angiotensin-System Activation In The Murine And Human Kidney, Oliver Domenig, Arndt Manzel, Nadja Grobe, Eva Königshausen, Christopher C. Kaltenecker, Johannes J. Kovarik, Susan B. Gurley, Dunja Van Oyen, Marlies Antlanger, Michael Bader, Daisy Motta-Santos, Jose Carlos Santos, Robson A. Santos, Khalid M. Elased, Marcus D. Säemann, Ralf A. Linker, Marko Poglitsch

Pharmacology and Toxicology Faculty Publications

Cardiovascular and renal pathologies are frequently associated with an activated renin-angiotensin-system (RAS) and increased levels of its main effector and vasoconstrictor hormone angiotensin II (Ang II). Angiotensin-converting-enzyme-2 (ACE2) has been described as a crucial enzymatic player in shifting the RAS towards its so-called alternative vasodilative and reno-protective axis by enzymatically converting Ang II to angiotensin-(1-7) (Ang-(1-7)). Yet, the relative contribution of ACE2 to Ang-(1-7) formation in vivo has not been elucidated. Mass spectrometry based quantification of angiotensin metabolites in the kidney and plasma of ACE2 KO mice surprisingly revealed an increase in Ang-(1-7), suggesting additional pathways to be responsible for …

Injury-Induced Microvesicle Particle Release In Keratinocyte Cell Line And Abdominoplasty Skin, Katherine E. Fahy, Langni Liu, Christina E. Borchers, Christine M. Rapp, Mike Kemp, Richard Simman, Ji C. Bihl, Jeffrey B. Travers

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Endothelial Progenitor Cells And Neural Progenitor Cells Synergistically Protect Cerebral Endothelial Cells From Hypoxia/Reoxygenation-Induced Injury Via Activating The Pi3k/Akt Pathway, Jinju Wang, Yusen Chen, Yi Yang, Xiang Xiao, Shuzhen Chen, Cheng Zhang, Bradley S. Jacobs, Bin Zhao, Ji C. Bihl, Yanfang Chen

Pharmacology and Toxicology Faculty Publications

Background

Protection of cerebral endothelial cells (ECs) from hypoxia/reoxygenation (H/R)-induced injury is an important strategy for treating ischemic stroke. In this study, we investigated whether co-culture with endothelial progenitor cells (EPCs) and neural progenitor cells (NPCs) synergistically protects cerebral ECs against H/R injury and the underlying mechanism.

Results

EPCs and NPCs were respectively generated from inducible pluripotent stem cells. Human brain ECs were used to produce an in vitro H/R-injury model. Data showed: 1) Co-culture with EPCs and NPCs synergistically inhibited H/R-induced reactive oxygen species (ROS) over-production, apoptosis, and improved the angiogenic and barrier functions (tube formation and permeability) in …

Uvb Generates Microvesicle Particles Via Platelet-Activating Factor-Receptor Signaling: A Novel Pathway By Which A Skin-Specific Stimulus Exerts Systemic Effects, Jeffrey B. Travers, Christine M. Rapp, Katherine E. Fahy, Christina E. Borchers, Richard Simman, Langni Liu, Yanfang Chen, Ji C. Bihl

Pharmacology and Toxicology Faculty Publications

Though Ultraviolet B radiation (290-320 nm; UVB) exerts profound systemic effects, it is absorbed only in the epidermis. One important question in photobiology is how UVB signals are emanated from the epidermis. Microvesicle particles (MVP) are small (200-1000nm diameter) membrane-bound vesicles released by numerous cell types and can be found in the circulation. MVP can contain both nuclear and cytoplasmic components and are thought to provide a mechanism by which cells transmit signals systemically. Though various stressors have been demonstrated to generate MVP, the ability of UVB to exert this effect has not been demonstrated. Previous studies from ours and …

Analyses Of Endothelial Cells And Endothelial Progenitor Cells Released Microvesicles By Using Microbead And Q-Dot Based Nanoparticle Tracking Analysis, Jinju Wang, Yun Zhong, Xiaotang Ma, Xiang Xiao, Chuanfang Cheng, Yusen Chen, Ifeanyi Iwuchukwu, Kenneth J. Gaines, Bin Zhao, Shiming Liu, Jeffrey B. Travers, Ji C. Bihl, Yanfang Chen

Pharmacology and Toxicology Faculty Publications

Accurate analysis of specific microvesicles (MVs) from biofluids is critical and challenging. Here we described novel methods to purify and detect MVs shed from endothelial cells (ECs) and endothelial progenitor cells (EPCs) by combining microbeads with fluorescence quantum dots (Q-dots) coupled nanoparticle tracking analysis (NTA). In the in vitroscreening systems, we demonstrated that 1) anti-CD105 (EC marker) and anti-CD34 (EPC marker) conjugated-microbeads had the highest sensitivity and specificity for isolating respective MVs, which were confirmed with negative controls, CD41 and CD235a; 2) anti-CD144 (EC marker) and anti-KDR (EPC marker) conjugated-Q-dots exhibited the best sensitivity and specificity for their respective …

The Novel Methods For Analysis Of Exosomes Released From Endothelial Cells And Endothelial Progenitor Cells, Jinju Wang, Runmin Guo, Yi Yang, Bradley S. Jacobs, Suhong Chen, Ifeanyi Iwuchukwu, Kenneth J. Gaines, Yanfang Chen, Richard Simman, Guiyuan Lv, Keng Wu, Ji C. Bihl

Pharmacology and Toxicology Faculty Publications

Exosomes (EXs) are cell-derived vesicles that mediate cell-cell communication and could serve as biomarkers. Here we described novel methods for purification and phenotyping of EXs released from endothelial cells (ECs) and endothelial progenitor cells (EPCs) by combining microbeads and fluorescence quantum dots (Q-dots®) techniques. EXs from the culture medium of ECs and EPCs were isolated and detected with cell-specific antibody conjugated microbeads and second antibody conjugated Q-dots by using nanoparticle tracking analysis (NTA) system. The sensitivities of the cell origin markers for ECs (CD105, CD144) and EPCs (CD34, KDR) were evaluated. The sensitivity and specificity were determined by using positive …

Microvascular Endothelial Cells-Derived Microvesicles Imply In Ischemic Stroke By Modulating Astrocyte And Blood Brain Barrier Function And Cerebral Blood Flow, Qunwen Pan, Caixia He, Hua Liu, Xiaorong Liao, Bingyan Dai, Yanfang Chen, Yi Yang, Bin Zhao, Ji C. Bihl, Xiaotang Ma

Pharmacology and Toxicology Faculty Publications

Background

Endothelial cell (EC) released microvesicles (EMVs) can affect various target cells by transferring carried genetic information. Astrocytes are the main components of the blood brain barrier (BBB) structure in the brain and participate in regulating BBB integrity and blood flow. The interactions between ECs and astrocytes are essential for BBB integrity in homeostasis and pathological conditions. Here, we studied the effects of human brain microvascular ECs released EMVs on astrocyte functions. Additionally, we investigated the effects of EMVs treated astrocytes on regulating BBB function and cerebral ischemic damage.

Results

EMVs prepared from ECs cultured in normal condition (n-EMVs) or …