Medicine and Health Sciences Commons^™

Developing A More Clinically-Relevant Mouse Model Of Cisplatin-Induced Nephrotoxicity., Cierra N. Sharp

Electronic Theses and Dissertations

Cisplatin is a nephrotoxic chemotherapeutic that causes acute kidney injury (AKI) in 30% of patients. Although recovery can occur after one episode of cisplatin-induced AKI, studies have indicated multiple episodes may lead to the development of chronic kidney disease (CKD), an irreversible disease with no current treatments. The standard mouse model of cisplatin-induced AKI consists of one, high dose of cisplatin (> 20 mg/kg) that is lethal to the animal three days later. This model doesn’t accurately reflect the repeated dosing regimen patients receive, and doesn’t allow for long-term outcome studies of pathologies associated with CKD. We have developed a …

Regulation Of Phosphatase And Tensin Homolog Expression And Activity By Transforming Growth-Factor Beta In The Trabecular Meshwork Cells: Implications For Primary Open Angle Glaucoma, Nikoleta Tellios

Electronic Thesis and Dissertation Repository

Glaucoma is a multifactorial condition caused, in part, by fibrosis of the sieve-like trabecular meshwork (TM) tissue, which impedes drainage of aqueous humor (AH), leading to increased intraocular pressure and associated optic nerve damage and blindness. Fibrosis of the TM is mainly caused by the increased levels of active transforming growth factor-β 2 (TGFβ2) in the AH of glaucoma patients.

Previous reports have shown that TGFβ decreases the expression of Phosphatase and Tensin Homolog (PTEN) gene and that PTEN is a major regulator of ECM deposition. In this study we investigate the regulation of PTEN protein expression and …

Na/K-Atpase Amplification Of Oxidant Stress; A Universal But Unrecognized Clinical Target?, Zijian Xie, Phd, Joseph I. Shapiro, Md

Joseph I Shapiro MD

The Na/K-ATPase has a signaling function which appears to be separate from its ion pumping function. This signaling function refers to the transduction of conformational changes in the Na/K-ATPase alpha1 subunit into activating Src’s tyrosine kinase activity, triggering a cascade which generates reactive oxygen species (ROS), modulates other signaling pathways, and causes many physiological and pathophysiological effects. We have recently observed that ROS themselves as well as cardiotonic steroids can actually initiate the signal by directly inducing conformational changes in alpha1. It therefore appears that the Na/K-ATPase signal cascade can serve as a feed forward amplification for ROS with circulating …

Na/K-Atpase Amplification Of Oxidant Stress; A Universal But Unrecognized Clinical Target?, Zijian Xie, Phd, Joseph I. Shapiro, Md

Marshall Journal of Medicine

The Na/K-ATPase has a signaling function which appears to be separate from its ion pumping function. This signaling function refers to the transduction of conformational changes in the Na/K-ATPase alpha1 subunit into activating Src’s tyrosine kinase activity, triggering a cascade which generates reactive oxygen species (ROS), modulates other signaling pathways, and causes many physiological and pathophysiological effects. We have recently observed that ROS themselves as well as cardiotonic steroids can actually initiate the signal by directly inducing conformational changes in alpha1. It therefore appears that the Na/K-ATPase signal cascade can serve as a feed forward amplification for ROS with circulating …

Angiogenic Therapy In A Fibrotic Murine Model Of Duchenne Muscular Dystrophy, Kelly M. Gutpell

Electronic Thesis and Dissertation Repository

Duchenne muscular dystrophy (DMD) is a devastating neuromuscular disorder that affects approximately 1 in 5000 males. Vascular-targeted therapy has been proposed as a treatment for DMD to reduce ischemia and enhance endogenous repair. Additionally, a more vascularized environment may enhance regenerative approaches currently under investigation. Vascular endothelial growth factor (VEGF) and angiopoietin-1 (ANG1) are two of the most studied pro-angiogenic factors for this approach. To date, little is known regarding the effect of these pro-angiogenic factors on muscle function and whether they may exacerbate fibrosis in a relevant murine model of DMD. The first aim of this thesis was to …

Rapamycin Attenuates Cardiac Fibrosis In Experimental Uremic Cardiomyopathy By Reducing Marinobufagenin Levels And Inhibiting Downstream Pro-Fibrotic Signaling, Steven T. Haller Phd, Yanling Yan Phd, Christopher A. Drummond Phd, Joe Xie Md, Jiang Tian Phd, David J. Kennedy Phd, Victoria Y. Shilova Phd, Zijian Xie Phd, Jiang Liu Phd, Christopher J. Cooper Md, Deepak Malhotra Md, Phd, Joseph I. Shapiro Md, Olga V. Fedorova Phd, Alexei Y. Bagrov Md, Phd

Pharmaceutical Science and Research

Background: Experimental uremic cardiomyopathy causes cardiac fibrosis and is causally related to the increased circulating levels of the cardiotonic steroid, marinobufagenin (MBG), which signals through Na/K‐ATPase. Rapamycin is an inhibitor of the serine/threonine kinase mammalian target of rapamycin (mTOR) implicated in the progression of many different forms of renal disease. Given that Na/K‐ATPase signaling is known to stimulate the mTOR system, we speculated that the ameliorative effects of rapamycin might influence this pathway.

Methods and Results: Biosynthesis of MBG by cultured human JEG‐3 cells is initiated by CYP27A1, which is also a target for rapamycin. It was demonstrated that 1 …

Epigenetic Modification Prevents Excessive Wound Healing And Scar Formation After Glaucoma Filtration Surgery, Ajay Sharma, Govindaraj Anumanthan, Marcos Reyes, Huiyi Chen, Jason W. Brubaker, Saad Siddiqui, Suneel Gupta, Frank G. Rieger, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

PURPOSE. The purpose of this study was to determine the efficacy of suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor (HDACi), in prevention of excessive wound healing and scar formation in a rabbit model of glaucoma filtration surgery (GFS).

METHODS. A rabbit model of GFS was used. Rabbits that underwent GFS received balanced salt solution, or SAHA (50 lM), or mitomycin C (0.02%). Clinical scores of IOP, bleb vascularity, and slit-lamp examination were performed. On postoperative day 14, rabbits were killed and the bleb tissues were collected for evaluation of tissue fibrosis with hematoxylin and eosin, Masson trichrome, a-smooth muscle …

Molecular Mechanisms Of Suberoylanilide Hydroxamic Acid In The Inhibition Of Tgf-Β1-Mediated Canine Corneal Fibrosis, Kristina M. Gronkiewicz, Elizabeth A. Giuliano, Ajay Sharma, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Objective—To investigate molecular mechanisms mediating anti-fibrotic effect of SAHA in the canine cornea using an in vitro model. We hypothesized that SAHA attenuates corneal fibrosis by modulating Smad-dependent and, to a lesser extent, Smad-independent signaling pathways activated by TGF-β1, as well as matrix metalloproteinase (MMP) activity.

Methods—Cultured canine corneal fibroblasts (CCF) were incubated in the presence/absence of TGF-β1 (5ng/ml) and SAHA (2.5μM) for 24hrs. Western blot analysis was used to quantify non-phosphorylated and phosphorylated isoforms of Smad2/3, p38 MAP kinase (MAPK), ERK1/2 and JNK1. Real-time PCR and zymography were utilized to quantify MMP1, MMP2, MMP8 and MMP9 mRNA expression and …

Effects Of Cepae Extract, Allantoin, And Heparin Mixture On Developing Andalready Formed Epidural Fibrosis In A Rat Laminectomy Model, Rafet Özay, Osman Yüksel Yavuz, Abi̇t Aktaş, Funda Yi̇ği̇t, Nuri̇ Eralp Çeti̇nalp, Haci Mustafa Özdemi̇r, Zeki̇ Şekerci̇

Turkish Journal of Medical Sciences

Background/aim: The study was designed to investigate whether local administration of a mixture composed of cepae extract, allantoin, and heparin (CAH) decreased already formed epidural fibrosis (EF) at the laminectomy site. Materials and methods: Twenty-four adult male Sprague Dawley rats were equally divided into four groups. Laminectomy was performed at the L5 level in all rats. The group 2 and group 4 rats were treated with local drug administration. While the group 1 and 2 rats were sacrificed after 6 weeks, the remaining rats were reoperated and CAH mixture was applied in group 4. The vertebral columns of all rats …

Efficacy Of Mitomycin-C And Infliximab In Reducing Adhesionand Fibrosis Following Strabismus Surgery*, Emi̇n Serbülent Güçlü, Ayşe Ayça Sari, Erdem Di̇nç, Tuba Özcan Meti̇n, Banu Coşkun Yilmaz, Bahar Taşdelen

Turkish Journal of Medical Sciences

Background/aim: The present study aimed to investigate the efficacy of mitomycin-C (MMC) and infliximab (INF) in reducing adhesion and fibrosis following strabismus surgery. Materials and methods: Forty eyes of 20 albino rabbits were separated into MMC and INF groups. Right and left eyes of rabbits were assigned to the drug and control groups, respectively. The superior rectus muscle was disinserted, the drug was administered to the surgical area for 5 min in the drug eyes (MMC 0.2 mg/mL or INF 5 mg/mL), and physiological saline was administered to the control eyes. Surgical areas were rinsed with 10 mL of physiological …