ABSTRACT
The effects of small-molecule p38 inhibitors in numerous models of different disease states have been published, including those of SD-282, an indole-5-carboxamide inhibitor. The aim of the present study was to evaluate the pharmacological activity of SD-282 on cytokine production in vitro as well as in 2 in vivo models of inflammation in order to illuminate the role of this particular inhibitor in diverse disease states. The results presented here provide further characterization of SD-282 and provide a context in which to interpret the activity of this p38 inhibitor in models of arthritis, pain, myocardial injury, sepsis and asthma; all of which have an inflammatory component. SD-282 represents a valuable tool to elucidate the role of p38 MAP kinase in multiple models of inflammation.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Enzyme Inhibitors/pharmacology , Indoles/pharmacology , Inflammation/drug therapy , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , Animals , Disease Models, Animal , Enzyme Inhibitors/pharmacokinetics , Female , Granulocytes/drug effects , Granulocytes/metabolism , Guinea Pigs , Humans , In Vitro Techniques , Indoles/pharmacokinetics , Lung/drug effects , Lung/pathology , Male , Mice , Mice, Inbred BALB C , Ovalbumin , Sepsis/drug therapy , Sepsis/physiopathology , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/drug effectsABSTRACT
Mitogen-activated protein kinases (MAPKs) and heat shock proteins (HSPs) are ubiquitous proteins that function within T cells in both normal and stress-related pathophysiological states, including type 1 diabetes. The nonobese diabetic (NOD) mouse spontaneously develops T cell-mediated autoimmune pancreatic beta cell destruction that is similar to type 1 diabetes in humans. Because p38 MAPKs have been shown to modulate T cell function, we studied the effects of a p38alpha MAPK-selective inhibitor, indole-5-carboxamide (SD-169), on the development and progression of type 1 diabetes in the NOD mouse. In preventive treatment studies, SD-169 significantly reduced p38 and HSP60 expression in T cells of the pancreatic beta islets. Following treatment, the incidence of diabetes as determined by blood glucose levels was significantly lower, and immuno-histochemistry of pancreatic beta islet tissue demonstrated significant reduction in CD5+ T cell infiltration in the SD-169 treatment group as compared with untreated NOD mice. In therapeutic studies using mildly and moderately hyperglycemic NOD mice, SD-169 treatment lowered blood glucose and improved glucose homeostasis. Furthermore, following cessation of SD-169 treatment, NOD mice showed significant arrest of diabetes. In conclusion, we report that this p38alpha-selective inhibitor prevents the development and progression of diabetes in NOD mice by inhibiting T cell infiltration and activation, thereby preserving beta cell mass via inhibition of the p38 MAPK signaling pathway. These results have bearing on current prophylactic and therapeutic protocols using p38alpha-selective inhibitors in the prediabetic period for children at high risk of type 1 diabetes, in the honeymoon period, and for adults with latent autoimmune diabetes.
Subject(s)
Diabetes Mellitus, Type 1/enzymology , Diabetes Mellitus, Type 1/prevention & control , Mitogen-Activated Protein Kinase 14/antagonists & inhibitors , Protein Kinase Inhibitors/therapeutic use , Animals , Diabetes Mellitus, Type 1/drug therapy , Female , Mice , Mice, Inbred NOD , Mitogen-Activated Protein Kinase 14/metabolism , Protein Kinase Inhibitors/pharmacologyABSTRACT
BACKGROUND: In mitogen-stimulated lymphocyte responses (sLR), cytokines and cell-surface receptors in peripheral human blood lymphocytes (PBL) are sensitive to cyclosporine (CsA), and can predict its in vivo effect with pharmacodynamic (PD) modeling. This is not known for multiple-agent combinations. METHODS: Twenty-five concentration mixtures of CsA (0-1200 ng/ml) plus sirolimus (SRL, 0-30 ng/ml) were added to whole blood from five normal human subjects (NHS) for effect on a limited array of six targets. Effect-concentration relationships were analyzed with E(max) PD equations, and expressed as the range of concentration mixtures associated with one-half of maximal inhibitory effect (EC(50)) on a model biomarker target. This predicted range was examined to see whether it contained representative concentration mixtures of these two drugs, which were associated with a stable post-transplant outcome in a logistic regression model of 1039 clinical trial patients. RESULTS: PD analyses suggested that in NHS samples containing CsA+SRL (n=5), (1) PMA-Ionomycin-stimulated T-cell expression of intracellular IL-2, TNF-alpha, and IFN-gamma was inhibited by CsA, and minimally by SRL, and (2) the two agents inhibited pokeweed mitogen (PWM)-stimulated B-cell expression of CD54 and CD95, but not CD86 (ICAM-1, Fas antigen, and B7.2), synergistically. With CD54 as the model biomarker, contour plots also predicted a wide range of concentration mixtures of the two agents across which an EC(50) could be predicted for CsA+SRL in a population (e.g., CsA-72 ng/ml+SRL 15 ng/ml, n=5), as well as in the individual subject (e.g., CsA-0 ng/ml+SRL-13.75 ng/ml in NHS-D310). Logistic regression analysis of clinical outcomes in 1039 patients suggested that the concentration mixture of CsA congruent with 50-150 ng/ml+SRL congruent with 10 ng/ml was associated with a stable post-transplant course. The EC(50) contour plot for CD54 suggested a nearly identical CsA concentration of 120 ng/ml in the presence of 10 ng/ml of sirolimus. CONCLUSIONS: Our data suggest that pharmacodynamic evaluation of immunosuppressive agents with biomarkers may be an efficient process with which to characterize immunosuppressive effect of combination agents in individual patients and in patient populations.
