Anti-inflammatory and antiproliferative actions of PPAR-gamma agonists on T lymphocytes derived from MS patients.
Peroxisomal proliferator-activated receptors (PPARs) belong to a nuclear receptor superfamily of ligand-activated transcription factors. The PPAR-gamma isoform is expressed in human T lymphocytes, and oral administration of PPAR-gamma agonists ameliorates the clinical course and histopathological features in experimental autoimmune encephalomyelitis, an animal model for multiple sclerosis, suggesting a potential role for PPAR-gamma agonists in the treatment of autoimmune diseases. To assess a potential therapeutic role of PPAR-gamma agonists in multiple sclerosis, we compared the immunomodulatory effects of the thiazolidinedione (TZD) drugs pioglitazone (PIO) and ciglitazone and the non-TZD PPAR-gamma agonist GW347845 on human T leukemia cells (Jurkat cells) and phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMCs) derived from 21 multiple sclerosis patients and 12 healthy donors. PIO, ciglitazone, and GW347845 suppressed PHA-induced T cell proliferation by 40-50% and secretion of interferon-gamma and tumor necrosis factor alpha, by 30-50%. Inhibition of proliferation was increased to approximately 80% and that of proinflammatory cytokine secretion, to 80-90% when PBMCs were first preincubated with PPAR-gamma agonists and re-exposed at the time of PHA stimulation, indicating a sensitizing effect of PPAR-gamma agonists. Inhibition of proliferation was also observed in the tetanus toxoid-specific T cell line KHS.TT2, albeit to a lesser extent. The antiproliferative effects of PIO and GW347845 were accompanied by a decrease of cell viability. Electron microscopy and Western blot analysis revealed DNA condensation and down-regulation of bcl-2, suggesting the induction of apoptosis in activated T lymphocytes. In summary, the data support the potential use of PPAR-gamma agonists as immunomodulatory, therapeutic agents for autoimmune diseases.
Schmidt
Stephan
S
Department of Neurology, University of Bonn, Germany.
Moric
Edin
E
Schmidt
Martina
M
Sastre
Magdalena
M
Feinstein
Douglas L
DL
Heneka
Michael T
MT
D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000293:Adolescent; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D016022:Case-Control Studies; D002455:Cell Division / Q000187:drug effects / Q000276:immunology; D016207:Cytokines / Q000378:metabolism; D005260:Female; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000276:immunology*; D000077205:Pioglitazone; D018160:Receptors, Cytoplasmic and Nuclear / Q000819:agonists*; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D045162:Thiazolidinediones / Q000494:pharmacology; D014157:Transcription Factors / Q000819:agonists*
D000276:Adjuvants, Immunologic; D000893:Anti-Inflammatory Agents; D016207:Cytokines; D018160:Receptors, Cytoplasmic and Nuclear; D045162:Thiazolidinediones; D014157:Transcription Factors; C039671:ciglitazone; D000077205:Pioglitazone