ABSTRACT
Jun N-terminal kinase (JNK) is a stress-activated protein kinase that can be induced by inflammatory cytokines, bacterial endotoxin, osmotic shock, UV radiation, and hypoxia. We report the identification of an anthrapyrazolone series with significant inhibition of JNK1, -2, and -3 (K(i) = 0.19 microM). SP600125 is a reversible ATP-competitive inhibitor with >20-fold selectivity vs. a range of kinases and enzymes tested. In cells, SP600125 dose dependently inhibited the phosphorylation of c-Jun, the expression of inflammatory genes COX-2, IL-2, IFN-gamma, TNF-alpha, and prevented the activation and differentiation of primary human CD4 cell cultures. In animal studies, SP600125 blocked (bacterial) lipopolysaccharide-induced expression of tumor necrosis factor-alpha and inhibited anti-CD3-induced apoptosis of CD4(+) CD8(+) thymocytes. Our study supports targeting JNK as an important strategy in inflammatory disease, apoptotic cell death, and cancer.
Subject(s)
Anthracenes/pharmacology , Enzyme Inhibitors/pharmacology , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Pyrazolones , Adenosine Triphosphate/metabolism , Animals , Anthracenes/chemistry , Anthracenes/metabolism , Anthraquinones , Binding, Competitive , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , Cell Differentiation/drug effects , Cells, Cultured , Cytokines/metabolism , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/metabolism , Female , Gene Expression/drug effects , Humans , JNK Mitogen-Activated Protein Kinases , Jurkat Cells , Lymphocyte Activation/drug effects , Mice , Mice, Inbred C57BL , Molecular Structure , Monocytes/cytology , Monocytes/metabolism , Protein Kinase Inhibitors , Pyrazoles , Structure-Activity Relationship , Tumor Necrosis Factor-alpha/biosynthesisABSTRACT
To investigate the role of interleukin 6 (IL-6) in adjuvant-induced arthritis, serum from adjuvant-immunized Lewis rats treated with cyclosporin, indomethacin, or saline was evaluated for IL-6 activity. Inflammation was quantitated by measuring paw volume. We found that an increase in serum IL-6 activity parallels the kinetics of paw edema development in adjuvant-immunized rats. Daily treatment with 5 mg cyclosporin A/kg prevented the increase in paw volume and held serum IL-6 activity to levels observed in untreated (normal) rats. Daily treatment with 1 mg indomethacin/kg resulted in a 50% reduction in serum IL-6 levels and a significant decrease (approximately 50%) in paw volume on Day 17 compared to saline-treated rats. Linear regression analysis confirmed the positive correlation between mean paw volume and mean serum IL-6 activity (R2 = 0.783, P less than 0.01 on Day 17) in normal, arthritic, and cyclosporin A- or indomethacin-treated groups. These results are consistent with a role for IL-6 in the pathology of arthritis and suggest that serum IL-6 activity may be a useful parameter for monitoring disease activity.
Subject(s)
Arthritis, Experimental/blood , Arthritis/blood , Cyclosporins/therapeutic use , Indomethacin/therapeutic use , Interleukin-6/blood , Animals , Arthritis, Experimental/drug therapy , Disease Models, Animal , Edema , Foot , Male , Mycobacterium tuberculosis , Rats , Rats, Inbred LewABSTRACT
The single-anastomosis heart-lung transplantation method in the rat developed by Lee and associates has been examined and has proven to be simple and reproducible. Technical procedures are discussed emphasizing those procedures that require special caution to ensure successful graft function. The donor and recipient rat strain combination has been found to influence the success of the transplantation procedure. Rat strain combinations used in our laboratories resulted in different percentages of donor heart survival. Using Lewis rat (RT1 1/1) recipients, 68% of Brown Norway rat (RT1n/n) donor hearts and 97% of NBR rat (RT1 1/1) donor hearts survived. However, only 29% of Fischer rat (RT1 1/1) donor hearts survived longer than 2 days when transplanted into Lewis rat recipients. In our laboratories, the Lee method of single-anastomosis heart-lung transplantation has been used successfully to evaluate whether immunoregulatory compounds alter heart allograft rejection.
