Rheumatology Commons^™

Mir-574-5p Activates Human Tlr8 To Promote Autoimmune Signaling And Lupus, Tao Wang, Dan Song, Xuejuan Li, Yu Luo, Dianqiang Yang, Xiaoyan Liu, Xiaodan Kong, Yida Xing, Shulin Bi, Yan Zhang, Tao Hu, Yunyun Zhang, Shuang Dai, Zhiqiang Shao, Dahan Chen, Jinpao Hou, Esteban Ballestar, Jianchun Cai, Feng Zheng, James Y Yang

Faculty, Staff and Student Publications

Endosomal single-stranded RNA-sensing Toll-like receptor-7/8 (TLR7/8) plays a pivotal role in inflammation and immune responses and autoimmune diseases. However, the mechanisms underlying the initiation of the TLR7/8-mediated autoimmune signaling remain to be fully elucidated. Here, we demonstrate that miR-574-5p is aberrantly upregulated in tissues of lupus prone mice and in the plasma of lupus patients, with its expression levels correlating with the disease activity. miR-574-5p binds to and activates human hTLR8 or its murine ortholog mTlr7 to elicit a series of MyD88-dependent immune and inflammatory responses. These responses include the overproduction of cytokines and interferons, the activation of STAT1 signaling …

Early Resveratrol Treatment Mitigates Joint Degeneration And Dampens Pain In A Mouse Model Of Pseudoachondroplasia (Psach), Jacqueline T Hecht, Alka C Veerisetty, Debabrata Patra, Mohammad G Hossain, Frankie Chiu, Claire Mobed, Francis H Gannon, Karen L Posey

Faculty, Staff and Student Publications

Pseudoachondroplasia (PSACH), a severe dwarfing condition associated with early-onset joint degeneration and lifelong joint pain, is caused by mutations in cartilage oligomeric matrix protein (COMP). The mechanisms underlying the mutant-COMP pathology have been defined using the MT-COMP mouse model of PSACH that has the common D469del mutation. Mutant-COMP protein does not fold properly, and it is retained in the rough endoplasmic reticulum (rER) of chondrocytes rather than being exported to the extracellular matrix (ECM), driving ER stress that stimulates oxidative stress and inflammation, driving a self-perpetuating cycle. CHOP (ER stress signaling protein) and TNFα inflammation drive high levels of mTORC1 …

Maackia Amurensis Seed Lectin (Masl) Increases Movement Velocity Of Mice With Tnfα Induced Rheumatoid Arthritis, Amanda A. Greenspan, Kelly L. Hamilton, Alan J. Shienbaum, Bradford Fischer, Andrea Bottaro, Gary S. Goldberg

Rowan-Virtua Research Day

Up to 70 million people around the world suffer from rheumatoid arthritis. Current treatment options have varied efficacy and can cause unwanted side effects. New approaches are needed to treat this condition. Sialic acid modifications on chondrocyte receptors have been associated with arthritic inflammation and joint destruction. The transmembrane mucin receptor protein podoplanin (PDPN) has been identified as a functionally relevant receptor that presents extracellular sialic acid motifs. PDPN signaling promotes inflammation and invasion associated with arthritis and, therefore, has emerged as a target that can be used to inhibit arthritic inflammation. Maackia amurensis seed lectin (MASL) can target PDPN …

Curq+, A Next-Generation Formulation Of Curcumin, Ameliorates Growth Plate Chondrocyte Stress And Increases Limb Growth In A Mouse Model Of Pseudoachondroplasia, Jacqueline T Hecht, Alka C Veerisetty, Mohammad G Hossain, Frankie Chiu, Karen L Posey

Faculty, Staff and Student Publications

Mutations in cartilage oligomeric matrix protein (COMP) causes protein misfolding and accumulation in chondrocytes that compromises skeletal growth and joint health in pseudoachondroplasia (PSACH), a severe dwarfing condition. Using the MT-COMP mice, a murine model of PSACH, we showed that pathological autophagy blockage was key to the intracellular accumulation of mutant-COMP. Autophagy is blocked by elevated mTORC1 signaling, preventing ER clearance and ensuring chondrocyte death. We demonstrated that resveratrol reduces the growth plate pathology by relieving the autophagy blockage allowing the ER clearance of mutant-COMP, which partially rescues limb length. To expand potential PSACH treatment options, CurQ+, a uniquely absorbable …

Protective Role Of Colitis In Inflammatory Arthritis Via Propionate-Producing Bacteroides In The Gut, Hoh-Jeong Shon, Yu-Mi Kim, Kyeong Seog Kim, Jin-Ouk Choi, Sang-Hyun Cho, Sujin An, Se-Hyeon Park, Yong-Joon Cho, Joo-Hong Park, Sang-Uk Seo, Joo-Youn Cho, Wan-Uk Kim, Donghyun Kim

Faculty, Staff and Student Publications

OBJECTIVES: To investigate whether and how inflammatory disease in the intestine influences the development of arthritis, considering that organ-to-organ communication is associated with many physiological and pathological events.

METHODS: First, mice were given drinking water containing dextran sodium sulfate (DSS) and then subjected to inflammatory arthritis. We compared the phenotypic symptoms between the cohoused and separately-housed mice. Next, donor mice were divided into DSS-treated and untreated groups and then cohoused with recipient mice. Arthritis was then induced in the recipients. The fecal microbiome was analyzed by 16S rRNA amplicon sequencing. We obtained type strains of the candidate bacteria and generated …

Protein Kinase Cδ And C-Abl Kinase Are Required For Transforming Growth Factor Β Induction Of Endothelial-Mesenchymal Transition In Vitro., Zhaodong Li, Sergio A. Jimenez

Department of Medicine Faculty Papers

OBJECTIVE: The origin of the mesenchymal cells responsible for the intimal fibrosis in systemic sclerosis (SSc) has not been fully identified. The present study was undertaken to investigate whether subendothelial mesenchymal cells may emerge through transdifferentiation of endothelial cells (ECs) into myofibroblasts via endothelial-mesenchymal transition (EndoMT) in vitro and to explore the signaling pathways involved in this process.

METHODS: Primary mouse pulmonary ECs isolated by immunomagnetic methods with sequential anti-CD34 and anti-CD102 antibody selection were cultured in monolayers. Cell morphology and diacetylated low-density lipoprotein uptake assays confirmed their EC characteristics. The induction of EndoMT was assessed by determination of α-smooth …

Decreased Expression Of Caveolin 1 In Patients With Systemic Sclerosis: Crucial Role In The Pathogenesis Of Tissue Fibrosis., Francesco Del Galdo, Federica Sotgia, Cecilia J. De Almeida, Jean-Francois Jasmin, Megan Musick, Michael P. Lisanti, Sergio A. Jimenez

Department of Medicine Faculty Papers

OBJECTIVE: Recent studies have implicated caveolin 1 in the regulation of transforming growth factor beta (TGFbeta) downstream signaling. Given the crucial role of TGFbeta in the pathogenesis of systemic sclerosis (SSc), we sought to determine whether caveolin 1 is also involved in the pathogenesis of tissue fibrosis in SSc. We analyzed the expression of CAV1 in affected SSc tissues, studied the effects of lack of expression of CAV1 in vitro and in vivo, and analyzed the effects of restoration of caveolin 1 function on the fibrotic phenotype of SSc fibroblasts in vitro.

METHODS: CAV1 expression in tissues was analyzed by …

Transcriptional Inhibition Of Type I Collagen Gene Expression In Scleroderma Fibroblasts By The Antineoplastic Drug Ecteinascidin 743., Natalia Louneva, Biagio Saitta, David J Herrick, Sergio A. Jimenez

Department of Medicine Faculty Papers

We previously showed that COL1A1 expression is up-regulated at the transcriptional level in systemic sclerosis (SSc) fibroblasts and that the CCAAT-binding factor (CBF) is involved in this increased expression. Ecteinascidin 743 (ET-743) is a chemotherapeutic agent that binds with sequence specificity to the minor groove of DNA and inhibits CBF-mediated transcriptional activation of numerous genes. Therefore, we examined the effects of ET-743 on the increased COL1A1 expression in SSc fibroblasts. The drug caused a potent and dose-dependent inhibition of type I collagen biosynthesis, which reached 70-90% at 700 pM without affecting cell viability. The same drug concentration caused 60-80% reduction …

Regulation Of Human Col9a1 Gene Expression. Activation Of The Proximal Promoter Region By Sox9., Ping Zhang, Sergio A. Jimenez, David G Stokes

Department of Medicine Faculty Papers

The COL9A1 gene contains two promoter regions, one driving expression of a long alpha1(IX) chain in cartilage (upstream) and one driving expression of a shorter chain in the cornea and vitreous (downstream). To determine how the chondrocyte-specific expression of the COL9A1 gene is regulated, we have begun to characterize the upstream chondrocyte-specific promoter region of the human COL9A1 gene. Transient-transfection analyses performed in rat chondrosarcoma (RCS) cells, human chondrosarcoma (HTB) cells, and NIH/3T3 cells showed that the COL9A1 promoter was active in RCS cells but not HTB or NIH/3T3 cells. Inclusion of the first intron had no effect on promoter …

Stimulation Of Alpha 1(I) Procollagen Gene Expression In Nih-3t3 Cells By The Human T Cell Leukemia Virus Type 1 (Htlv-1) Tax Gene., E. Munoz, D. Suri, S. Amini, K. Khalili, Sergio A. Jimenez

Selected Works of Sergio Jiménez, MD, MACR

The mechanisms that regulate the expression of genes encoding extracellular matrix proteins in fibroblasts and other mesenchymal cells have remained elusive. Studies from several laboratories have indicated that Tax, a trans-regulatory protein from the human T cell leukemia virus type I not only augments viral gene expression but also triggers the expression of various cellular genes. Here, we examined the hypothesis that the expression of collagen genes may also be modulated by Tax. NIH-3T3 cells were simultaneously transfected with a Tax expressor plasmid and a chimeric construct containing regulatory sequences (-804 to +42 bp) of the alpha 1(I) procollagen gene …

Increased Alpha 1(I) Procollagen Gene Expression In Tight Skin (Tsk) Mice Myocardial Fibroblasts Is Due To A Reduced Interaction Of A Negative Regulatory Sequence With Ap-1 Transcription Factor., Neena Philips, Reza I. Bashey, Sergio A. Jimenez

Department of Medicine Faculty Papers

The TSK mouse, a model of fibrosis, displays exaggerated connective tissue accumulation in skin and visceral organs including the heart. To study the mechanisms of myocardial fibrosis in TSK mice, we established several strains of TSK mice myocardial fibroblasts in culture and examined the regulation of collagen gene expression in these cells. These strains displayed increased collagen gene expression in comparison with myocardial fibroblasts established from normal mice. On an average, the TSK myocardial fibroblast cultures showed a 4-fold increase in collagen synthesis and 4.4- and 3.6-fold increases, respectively, in alpha 1(I) and alpha 1(III) collagen mRNA steady state levels. …

Epidermal Growth Factor Coordinately Regulates The Expression Of Prostaglandin G/H Synthase And Cytosolic Phospholipase A2 Genes In Embryonic Mouse Cells., Kenneth P. Chepenik, Arturo Diaz, Sergio A. Jimenez

Department of Medicine Faculty Papers

Confluent, primary cultures of mouse embryo palate mesenchyme (MEPM) cells are refractory to activation of phospholipase A2 (PLA2) by the calcium ionophore A23187. However, treatment of these cultures with epidermal growth factor (EGF) permits the cells to activate PLA2 in response to A23187. We have developed this finding by exploring molecular mechanisms by which growth factors modulate mobilization and metabolism of arachidonic acid. We found chronic treatment (> 6 h) of confluent MEPM cells with EGF (a) increases their ability to metabolize exogenous arachidonic acid to prostaglandin E2 (PGE2) and (b) stimulated constitutive expression of activities of PLA2 and cyclooxygenase …

Functional Analysis Of Human Alpha 1(I) Procollagen Gene Promoter. Differential Activity In Collagen-Producing And -Nonproducing Cells And Response To Transforming Growth Factor Beta 1., Sergio A. Jimenez, John A. Varga, Anne Olsen, Liye Li, Arturo Diaz, Janet Herhal, Julie Koch

Department of Medicine Faculty Papers

To gain a further understanding of the regulation of human type I collagen gene expression under physiologic and pathologic conditions, we characterized 5.3 kilobase pairs (kb) of the human alpha 1(I) procollagen gene promoter. A series of deletion constructs containing portions of the alpha 1(I) procollagen 5'-flanking region (with end points from -5.3 kb to -84 base pairs (bp)) ligated to the chloramphenicol acetyltransferase (CAT) reporter gene were transiently transfected into NIH/3T3 cells. Maximal CAT activity was observed with constructs having 5' end points from -804 to -174 bp. A further 5' deletion to -84 bp caused a marked reduction …

The Tight Skin Mouse: Demonstration Of Mutant Fibrillin-1 Production And Assembly Into Abnormal Microfibrils, Cay M. Kielty, Michael Raghunath, Linda D. Siracusa, Michael J. Sherratt, Reiner Peters, C. Adrian Shuttleworth, Sergio A. Jimenez

Selected Works of Sergio Jiménez, MD, MACR

Mice carrying the Tight skin (Tsk) mutation harbor a genomic duplication within the fibrillin-1 (Fbn 1) gene that results in a larger than normal in-frame Fbn 1 transcript. In this study, the consequences of the Tsk mutation for fibrillin-containing microfibrils have been examined. Dermal fibroblasts from Tsk/+ mice synthesized and secreted both normal fibrillin (approximately 330 kD) and the mutant oversized Tsk fibrillin-1 (approximately 450 kD) in comparable amounts, and Tsk fibrillin-1 was stably incorporated into cell layers. Immunohistochemical and ultrastructural analyses of normal and Tsk/+ mouse skin highlighted differences in the gross organization and distribution of microfibrillar arrays. Rotary …

Expression Of A Human Cartilage Procollagen Gene (Col2a1) In Mouse 3t3 Cells., Leena Ala-Kokko, James Hyland, Carol Smith, Kari I. Kivirikko, Sergio A. Jimenez, Darwin J. Prockop

Department of Medicine Faculty Papers

Expression in a recombinant system has been difficult to obtain for any of the major fibrillar collagens that require processing by eight or more post-translational enzymes. Here, two DNA constructs were designed so that the promoter region of the gene for the pro-alpha 1(I) chain of human type I procollagen drove expression of the human type II procollagen gene in mouse NIH 3T3 cells, a culture line that normally synthesizes type I procollagen but not any cartilage-specific protein such as type II procollagen. Both constructs were expressed as both mRNA and protein. In clones expressing the construct at high levels, …