RESUMO
Administration of endotoxin (LPS) in humans results in profound physiological responses, including activation of peripheral blood mononuclear cells and the release of inflammatory factors. The time course of the response of selected inflammatory proteins was examined in healthy subjects (n = 6) administered a single intravenous dose of the purified derivative of endotoxin (3.0 ng/kg). Microarray analysis demonstrated changes in the expression of a number of genes, which were confirmed in separate in vitro endotoxin stimulation experiments. Subsequent TaqMan analysis of genes of interest indicated time-dependent changes in the expression of many of these genes. This included pre-B cell enhancing factor, which was identified on microarray analysis as being markedly upregulated following endotoxin stimulation. Protein expression of the genes examined by TaqMan analysis was measured and demonstrated the appearance of tumor necrosis factor (TNF)-alpha and sTNF-R proteins in the plasma beginning within 1 h after dosing, followed by other cytokines/ inflammatory markers (e.g., IL-1ra, G-CSF, IL-6, IL-8, and IL-10) and suppressors of cytokine signaling (SOCS-1 and SOCS-3). In general, cytokine protein expression correlated well with gene expression; however, the temporal profile of expression of some genes did not correlate well with the protein data. For many of these proteins, the lack of correlation was attributable to alternate tissue sources, which were demonstrated on TaqMan analysis. Principal component analysis indicated that cytokines could be grouped according to their temporal pattern of response, with most transcript levels returning to baseline 24 h following endotoxin administration. The combination of cDNA microarray and TaqMan analysis to identify and quantify changes in gene expression, along with the analysis of protein expression, can be useful in investigating inflammatory and other diseases.
Assuntos
Citocinas/metabolismo , Endotoxinas/administração & dosagem , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas/análise , Adolescente , Adulto , Endotoxinas/farmacologia , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Inflamação/patologia , Injeções Intravenosas , Interleucina-1/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Cinética , Masculino , Análise em Microsséries , Nicotinamida Fosforribosiltransferase , Reação em Cadeia da Polimerase , Proteínas/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para CimaRESUMO
Clinical pharmacology is the investigation of drug effects in humans. This review discusses the basic tenets of clinical pharmacology research, including pharmacokinetic and pharmacodynamic analysis, therapeutic window, and clinical trial design, and the issues that may arise in the application of transcriptome analysis to clinical pharmacology studies. Examples of how transcriptome analysis can be applied to clinical pharmacology research are described, including a model system of endotoxin challenge (in vitro and in vivo), and an example of a cross-over drug study in normal volunteers. Various data display and analysis methods are also illustrated, including principal component analysis, hierarchical cluster analysis, and pathways analysis.
