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Full-Text Articles in Medicinal and Pharmaceutical Chemistry

Proteoglycan 4 (Prg4)/Lubricin And The Extracellular Matrix In Gout, Khaled A. Elsaid, Gregory D. Jay, Ru Liu-Bryan, Robert Terkeltaub Jul 2023

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 …


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 Apr 2022

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 …


A Two Compartment Pharmacokinetic Model Describes The Intra‐Articular Delivery And Retention Of Rhprg4 Following Acl Transection In The Yucatan Mini Pig, Mark Hurtig, Iman Zaghoul, Heather Sheardown, Tannin A. Schmidt, Lina Liu, Ling Zhang, Khaled A. Elsaid, Gregory D. Jay Nov 2018

A Two Compartment Pharmacokinetic Model Describes The Intra‐Articular Delivery And Retention Of Rhprg4 Following Acl Transection In The Yucatan Mini Pig, Mark Hurtig, Iman Zaghoul, Heather Sheardown, Tannin A. Schmidt, Lina Liu, Ling Zhang, Khaled A. Elsaid, Gregory D. Jay

Pharmacy Faculty Articles and Research

Treatment of the injured joint with rhPRG4 is based on recent observations that inflammation diminishes expression of native PRG4. Re‐establishing lubrication between pressurized and sliding cartilage surfaces during locomotion promotes the nascent expression of PRG4 and thus intra‐articular (IA) treatment strategies should be supported by pharmacokinetic evidence establishing the residence time of rhPRG4. A total of 21 Yucatan minipigs weighing ∼55 Kg each received 4 mg of 131I‐rhPRG4 delivered by IA injection 5 days following surgical ACL transection. Animals were sequentially euthanized following IA rhPRG4 at 10 mins (time zero), 24, 72 hrs, 6, 13 and 20 days later. The …