Musculoskeletal Diseases Commons^™

Disruption Of Proteoglycan 4 (Prg4)-Cd44 Signaling Modulates Chronic Synovitis In Conditionally Inactivated Mice, Khaled A. Elsaid, Ling Zhang, Thomas Zhao, Ava Marks, Derek Jenkins, Gregory D. Jay

Pharmacy Faculty Articles and Research

Background

Proteoglycan-4 (PRG4) is a mucinous glycoprotein secreted by synovial fibroblasts and superficial zone chondrocytes. PRG4 inhibits synovial macrophage (SM) activation via xanthine oxidase (XO) and hypoxia inducible factor alpha (HIF-1α) suppression. We aimed to evaluate the contribution of PRG4-CD44 interaction to synovial homeostasis and investigate PRG4’s signaling dysfunction in synovial tissues from patients with osteoarthritis (OA). We hypothesized that CD44 mediates synovitis due to PRG4 loss and that PRG4 signaling dysfunction is associated with high-grade synovitis in OA.

Methods

Prg4^{FrtloxP/FrtloxP} are transgenic mice wherein tamoxifen (TAM) inactivates the Frt allele and creates a knockout state (Prg4^{FrtKO/FrtKO …}

P-78. Susceptibility Of Omadacycline In Bone And Joint Infections: Pathogen Susceptibility And Regimen Decisions From An Ongoing Randomized Controlled Trial, Amy Y. Kang, Evelyn A. Flores, Donna Phan Tran, Buchen (Olivia) Han, Isabel Payan, Guarina Garcia Delgado, Loren G. Miller

Pharmacy Faculty Articles and Research

Background   Treatment of Bone and joint infections (BJIs) with oral antibiotics may have benefits compared to IV therapy. Yet oral treatment options may be limited by lack of options due to antibiotic-resistant pathogens and tolerability concerns. Omadacycline has in vitro activity against common BJI pathogens, including MRSA and most Enterobacterales. However, real-world susceptibility data and implications for oral therapy are limited.   Methods

We conducted a descriptive analysis of data from adult patients enrolled to date in an open-label, randomized controlled trial of comparing omadacycline-containing antibiotic regimen vs. standard of care (SOC) antibiotics for BJIs. Omadaycline susceptibility was assessed on available …

Safety Of Omadacycline Versus Standard-Of-Care Oral Antibiotic Treatment For Bone And Joint Infections: Interim Results From An Open-Label, Non- Inferiority, Randomized Controlled Trial, Amy Y. Kang, Guarina Garcia Delgado, Donna Phan Tran, Evelyn A. Flores, Vanessa Romo-Kozan, Isabel Payan, Loren G. Miller

Pharmacy Faculty Articles and Research

Background

The incidence of bone and joint infections (BJIs) continues to increase, and existing oral BJI antibiotics have limitations. Omadacycline may be a potential treatment option for BJI treatment due to activity against doxycycline-resistant S. aureus and ESBL-producing Enterobacterales for which there are often no viable oral options. However, the safety of omadacycline in this setting is poorly defined.

Methods

We performed an open label, randomized, controlled clinical trial of adults with BJIs in the outpatient setting. Participants were randomized to omadacycline-containing regimen (omadacycline 300mg po daily) or Standard-of-Care (SOC) antibiotics. Adjunctive antibiotics were permitted in addition to omadacycline. Safety …

Proteoglycan 4 (Lubricin) And Regulation Of Xanthine Oxidase In Synovial Macrophage As A Mechanism Of Controlling Synovitis, Khaled A. Elsaid, Ling X. Zhang, Thomas Zhao, Ava Marks, Derek Jenkins, Tannin A. Schmidt, Gregory D. Jay

Pharmacy Faculty Articles and Research

Background

Synovial macrophages (SMs) are important effectors of joint health and disease. A novel Cx3CR1 + TREM2 + SM population expressing the tight junction protein claudin-5, was recently discovered in synovial lining. Ablation of these SMs was associated with onset of arthritis. Proteoglycan 4 (PRG4) is a mucinous glycoprotein that fulfills lubricating and homeostatic roles in the joint. The aim of this work is to study the role of PRG4 in modulating synovitis in the context of SM homeostasis and assess the contribution of xanthine oxidase (XO)-hypoxia inducible factor alpha (HIF-1a) axis to this regulation.

Methods

We used Prg4FrtloxP/FrtloxP …

Murine Models Of Graft Versus Host Disease (Gvhd): Focus On Ocular Gvhd, Philipp Steven, Victor L. Perez, Ajay Sharma

Pharmacy Faculty Articles and Research

Graft versus host disease (GVHD) remains a major and serious complication of allogeneic hematopoietic stem cell transplantation. Based on the time of onset, clinical phenotypes, progression kinetics, and pathophysiology, GVHD is stratified into acute, chronic, and overlapping types. The eyes are among the most commonly affected organs in GVHD. Mouse models have played an important role in understanding the several key elements of GVHD pathobiology. The current review discusses the immunology, pathology, and key phenotypic features of mouse models of systemic GVHD. Furthermore, a critical appraisal of mouse models of ocular GVHD (oGVHD) is provided. The disease mechanisms …

Proteoglycan 4 (Prg4)/Lubricin And The Extracellular Matrix In Gout, Khaled A. Elsaid, Gregory D. Jay, Ru Liu-Bryan, Robert Terkeltaub

Pharmacy Faculty Articles and Research

Proteoglycan 4 (PRG4) is a mucinous glycoprotein secreted by synovial fibroblasts and superficial zone chondrocytes, released into synovial fluid, and adsorbed on cartilage and synovial surfaces. PRG4′s roles include cartilage boundary lubrication, synovial homeostasis, immunomodulation, and suppression of inflammation. Gouty arthritis is mediated by monosodium urate (MSU) crystal phagocytosis by synovial macrophages, with NLRP3 inflammasome activation and IL-1β release. The phagocytic receptor CD44 mediates MSU crystal uptake by macrophages. By binding CD44, PRG4 limits MSU crystal uptake and downstream inflammation. PRG4/CD44 signaling is transduced by protein phosphatase 2A, which inhibits NF-κB, decreases xanthine oxidoreductase (XOR), urate production, and ROS-mediated IL-1β …

Development And Validation Of An Ultrahigh-Performance Liquid Chromatography–Tandem Mass Spectrometry Method To Investigate The Plasma Pharmacokinetics Of A KCa2.2/KCa2.3 Positive Allosteric Modulator In Mice, Mohammad Asikur Rahman, Devaraj Venkatapura Chandrashekar, Young-Woo Nam, Basir Syed, David Salehi, Hamidreza Montazeri Aliabadi, Miao Zhang, Reza Mehvar

Pharmacy Faculty Articles and Research

Rationale

There is currently no treatment for spinocerebellar ataxias (SCAs), which are a group of genetic disorders that often cause a lack of coordination, difficulty walking, slurred speech, tremors, and eventually death. Activation of K_Ca2.2/K_Ca2.3 channels reportedly exerts beneficial effects in SCAs. Here, we report the development and validation of an analytical method for quantitating a recently developed positive allosteric modulator of K_Ca2.2/K_Ca2.3 channels (compound 2q) in mouse plasma.

Methods

Mouse plasma samples (10 μL) containing various concentrations of 2q were subjected to protein precipitation in the presence of a structurally similar …

Protein Phosphatase 2a Regulates Xanthine Oxidase-Derived Ros Production In Macrophages And Influx Of Inflammatory Monocytes In A Murine Gout Model, Sandy Elsayed, Khaled A. Elsaid

Pharmacy Faculty Articles and Research

Background: Gout is a common arthritis, due to deposition of monosodium urate (MSU) crystals which results in IL-1β secretion by tissue-resident macrophages. Xanthine oxidase (XO) catalyzes uric acid (UA) production and in the process, reactive oxygen species (ROS) are generated which contributes to NLRP3 inflammasome activation. Protein phosphatase 2A (PP2A) may be involved in regulating inflammatory pathways in macrophages. The objective of this study was to investigate whether PP2A regulates gout inflammation, mediated by XO activity modulation. We studied UA and ROS generations in MSU stimulated murine bone marrow derived macrophages (BMDMs) in response to fingolimod phosphate, a PP2A activator, …

Quadruped Gait And Regulation Of Apoptotic Factors In Tibiofemoral Joints Following Intra-Articular Rhprg4 Injection In Prg4 Null Mice, Daniel S. Yang, Edward E. Dickerson, Ling X. Zhang, Holly Richendrfer, Padmini N. Karamchedu, Gary A. Badger, Tannin A. Schmidt, Alger M. Fredericks, Khaled A. Elsaid, Gregory D. Jay

Pharmacy Faculty Articles and Research

Camptodactyly-arthropathy-coxa vara-pericarditis (CACP) syndrome leads to diarthrodial joint arthropathy and is caused by the absence of lubricin (proteoglycan 4—PRG4), a surface-active mucinous glycoprotein responsible for lubricating articular cartilage. In this study, mice lacking the orthologous gene Prg4 served as a model that recapitulates the destructive arthrosis that involves biofouling of cartilage by serum proteins in lieu of Prg4. This study hypothesized that Prg4-deficient mice would demonstrate a quadruped gait change and decreased markers of mitochondrial dyscrasia, following intra-articular injection of both hindlimbs with recombinant human PRG4 (rhPRG4). Prg4^−/− (N = 44) mice of both sexes were injected with rhPRG4 …

Proteoglycan-4 Regulates Fibroblast To Myofibroblast Transition And Expression Of Fibrotic Genes In The Synovium, Marwa Qadri, Gregory D. Jay, Ling X. Zhang, Holly Richendrfer, Tannin A. Schmidt, Khaled A. Elsaid

Pharmacy Faculty Articles and Research

Background: Synovial tissue fibrosis is common in advanced OA with features including the presence of stress fiber-positive myofibroblasts and deposition of cross-linked collagen type-I. Proteoglycan-4 (PRG4) is a mucinous glycoprotein secreted by synovial fibroblasts and is a major component of synovial fluid. PRG4 is a ligand of the CD44 receptor. Our objective was to examine the role of PRG4-CD44 interaction in regulating synovial tissue fibrosis in vitro and in vivo.

Methods: OA synoviocytes were treated with TGF-β ± PRG4 for 24h and α-SMA content was determined using immunofluorescence. Rhodamine-labeled rhPRG4 was incubated with OA synoviocytes ± anti-CD44 or …

Cd44 Receptor Mediates Urate Crystal Phagocytosis By Macrophages And Regulates Inflammation In A Murine Peritoneal Model Of Acute Gout, Emira Bousoik, Marwa Qadri, Khaled A. Elsaid

Pharmacy Faculty Articles and Research

Gout is a chronic arthritis caused by the deposition of poorly soluble monosodium urate monohydrate (MSU) crystals in peripheral joints. Resident macrophages initiate inflammation in response to MSU mediated by NF-κB nuclear translocation and NLRP3 inflammasome activation. We investigated the role of CD44, a transmembrane receptor, in mediating MSU phagocytosis by macrophages. We used an antibody that sheds the extracellular domain (ECD) of CD44 to study the role of the receptor and its associated protein phosphatase 2A (PP2A) in macrophage activation. We also studied the significance of CD44 in mediating MSU inflammation in-vivo. Cd44^−/− BMDMs showed reduced MSU …

Design And Biological Evaluation Of Colchicine-Cd44-Targeted Peptide Conjugate In An In Vitro Model Of Crystal Induced Inflammation, Khalid A. Zoghebi, Emira Bousoik, Keykavous Parang, Khaled A. Elsaid

Pharmacy Faculty Articles and Research

Gout is an inflammatory arthritis due to the joint deposition of monosodium urate (MSU) crystals. Phagocytosis of MSU crystals by tissue macrophages results in the generation of reactive oxygen species (ROS) and production of inflammatory cytokines and chemokines. Colchicine use in gout is limited by severe toxicity. CD44 is a transmembrane glycoprotein that is highly expressed in tissue macrophages and may be involved in gout pathogenesis. The P6 peptide is a 20-amino acid residue peptide that binds to CD44. We hypothesized that the conjugation of colchicine to the P6 peptide would reduce its off-target cytotoxicity while preserving its anti-inflammatory effect. …

Changes In The Utilization Of Osteoporosis Drugs After The 2010 Fda Bisphosphonate Drug Safety Communication, Bander Balkhi, Enrique Seoane-Vazquez, Rosa Rodriguez-Monguio

Pharmacy Faculty Articles and Research

Introduction

In October 2010, the US Food and Drug Administration (FDA) issued a safety communication regarding the risks of atypical fractures of the femur, with bisphosphonates drugs. This study evaluated the impact of the bisphosphonates FDA safety communication on the utilization of osteoporosis medications in Medicaid programs.

Methods

Osteoporosis drugs utilization data from the July 2006 to June 2014 were extracted from the national Summary Files from the Medicaid State Drug Utilization Data maintained by the Centers for Medicare & Medicaid Services (CMS). We performed an interrupted time series analyses to evaluate trends in utilization of osteoporosis drugs before and …

Calcium Phosphate As A Key Material For Socially Responsible Tissue Engineering, Vuk Uskoković, Victoria M. Wu

Pharmacy Faculty Articles and Research

Socially responsible technologies are designed while taking into consideration the socioeconomic, geopolitical and environmental limitations of regions in which they will be implemented. In the medical context, this involves making therapeutic platforms more accessible and affordable to patients in poor regions of the world wherein a given disease is endemic. This often necessitates going against the reigning trend of making therapeutic nanoparticles ever more structurally complex and expensive. However, studies aimed at simplifying materials and formulations while maintaining the functionality and therapeutic response of their more complex counterparts seldom provoke a significant interest in the scientific community. In this review …

Intra-Articular Interleukin-1 Receptor Antagonist (Il1-Ra) Microspheres For Posttraumatic Osteoarthritis: In Vitro Biological Activity And In Vivo Disease Modifying Effect, Khaled A. Elsaid, Anand Ubhe, Ziyad Shaman, Gerard D'Souza

Pharmacy Faculty Articles and Research

Background: Interleukin-1 receptor antagonist (IL-1 ra) can be disease-modifying in posttraumatic osteoarthritis (PTOA). One limitation is its short joint residence time. We hypothesized that IL-1 ra encapsulation in poly (lactide-co-glycolide) (PLGA) microspheres reduces IL-1 ra systemic absorption and provides an enhanced anti-PTOA effect.

Methods: IL-1 ra release kinetics and biological activity: IL-1 ra encapsulation into PLGA microsphere was performed using double emulsion solvent extraction. Lyophilized PLGA IL-1 ra microspheres were resuspended in PBS and supernatant IL-1 ra concentrations were assayed. The biological activity of IL-1 ra from PLGA IL-1 ra microspheres was performed using IL-1 induced lymphocyte proliferation …