Dermatology Commons^™

Effect Of Oxidative Stress On Protein Tyrosine Phosphatase 1b In Scleroderma Dermal Fibroblasts., Pei-Suen Tsou, Nadine N. Talia, Adam J. Pinney, Ann Kendzicky, Sonsoles Piera-Velazquez, Sergio A. Jimenez, James R. Seibold, Kristine Phillips, Alisa E Koch

Department of Dermatology and Cutaneous Biology Faculty Papers

OBJECTIVE: Platelet-derived growth factor (PDGF) and its receptor, PDGFR, promote fibrosis in systemic sclerosis (SSc; scleroderma) dermal fibroblasts, and such cells in scleroderma skin lesions produce excessive reactive oxygen species (ROS). PDGFR is phosphorylated upon PDGF stimulation, and is dephosphorylated by protein tyrosine phosphatases (PTPs), including PTP1B. This study was undertaken to determine whether the thiol-sensitive PTP1B is affected by ROS in SSc dermal fibroblasts, thereby enhancing the phosphorylation of PDGFR and synthesis of type I collagen. This study also sought to investigate the effect of a thiol antioxidant, N-acetylcysteine (NAC), in SSc.

METHODS: Fibroblasts were isolated from the skin …

A Prospective Observational Study Of Mycophenolate Mofetil Treatment In Progressive Diffuse Cutaneous Systemic Sclerosis Of Recent Onset., Fabian A. Mendoza, Md, Sarah J. Nagle, Jason B. Lee, Md, Sergio A. Jimenez

Jefferson Institute of Molecular Medicine Papers and Presentations

OBJECTIVE: A prospective observational study of mycophenolate mofetil (MMF) treatment in patients with diffuse progressive cutaneous systemic sclerosis (SSc) of recent onset.

METHODS: Twenty-five previously untreated consecutive patients with recent-onset (< 24 mo) diffuse progressive cutaneous SSc received MMF as the only disease-modifying therapy. Modified Rodnan skin score (mRSS) and affected body surface area (BSA) were compared from initiation of MMF to study end. Pulmonary function tests performed at the same institution before therapy and at study end were available in 15 patients. Histopathology and real-time PCR assessment of fibrosis-related gene expression were performed before and after treatment in skin biopsies from 3 patients.

RESULTS: At 18.2 ± 8.73 months of MMF therapy (median 2000 mg/day) the mRSS decreased from 24.56 ± 8.62 to 14.52 ± 10.9 (p = 0.0004) and the affected BSA from 36% ± 16% to 14% ± 13.3% (p = 0.00001). Pulmonary function tests remained stable from initiation of MMF to the end of the study. Skin histopathology showed a remarkable reduction in accumulation of fibrotic tissue. Real-time PCR …