ABSTRACT
El Consejo Federal de Medicina de Brasil (CFM) -órgano normativo y fiscalizador del ejercicio ético de la medicina- prohibió, en 2008, la participación de médicos brasileños en investigaciones que utilizaran placebo para enfermedades con tratamiento eficaz y efectivo, en contraposición a la Declaración de Helsinki, que permite su uso en condiciones metodológicamente justificadas. Con el objetivo de verificar si la normativa ética del CFM modificó el uso de placebo en ensayos clínicos de fase III en Brasil, se analizaron varias características de sus registros en el ClinicalTrials.gov, en los períodos de 2003 a 2007 y de 2009 a 2013. Se concluye que: a) la normativa promulgada por el CFM en 2008 fue ineficaz y prevaleció la posición adoptada por la Declaración de Helsinki; b) el patrocinio de ensayos con placebo por parte de la industria farmacéutica multinacional fue significativo; c) predominaron las investigaciones de fármacos para enfermedades crónicas, y fueron poco significativas para las enfermedades postergadas, de importancia para Brasil.
In 2008, Brazil's Federal Council of Medicine [Conselho Federal de Medicina] (CFM) - regulatory and supervisory agency on the ethical practice of medicine - banned the participation of Brazilian doctors in studies using placebos for diseases with efficient and effective treatment. This position differs with the Helsinki Declaration, which allows the use of placebos in methodologically justified conditions. To ascertain whether the CMF's ethical regulation modified the use of placebos in phase III clinical trials in Brazil, characteristics of the records in ClinicalTrials.gov were researched in the periods from 2003 to 2007 and from 2009 to 2013. The conclusions reached were: a) the regulations issued by the CFM in 2008 were ineffective and the position adopted by the Helsinki Declaration prevails; b) there was significant sponsorship by the multinational pharmaceutical industry of trials with placebos; c) the research was predominantly on new drugs for chronic diseases, with little study done of the neglected diseases which are of great importance to Brazil.
Subject(s)
Animals , Rats , Apoptosis/genetics , Gene Expression Regulation, Enzymologic/genetics , Heme/deficiency , Nerve Degeneration/genetics , Neurons/metabolism , Porphyrias/complications , Apoptosis/drug effects , Caspases/drug effects , Caspases/metabolism , Cell Survival/drug effects , Cell Survival/genetics , Collagen Type XI/drug effects , Collagen Type XI/metabolism , Cyclic AMP Response Element-Binding Protein/drug effects , Cyclic AMP Response Element-Binding Protein/genetics , Cyclic AMP Response Element-Binding Protein/metabolism , Down-Regulation/drug effects , Down-Regulation/physiology , Enzyme Inhibitors , Gene Expression Regulation, Enzymologic/drug effects , Heme/biosynthesis , Heptanoates , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/physiology , Membrane Proteins/drug effects , Membrane Proteins/genetics , Membrane Proteins/metabolism , Nerve Degeneration/metabolism , Nerve Degeneration/physiopathology , Nerve Tissue Proteins/drug effects , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neural Cell Adhesion Molecules/drug effects , Neural Cell Adhesion Molecules/genetics , Neural Cell Adhesion Molecules/metabolism , Neurons/drug effects , Neurons/pathology , Poly(ADP-ribose) Polymerases , Porphyrias/metabolism , Porphyrias/physiopathology , RNA, Messenger/drug effects , RNA, Messenger/metabolism , RNA-Binding Proteins/drug effects , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , SMN Complex Proteins , Up-Regulation/drug effects , Up-Regulation/physiology , Vesicular Transport Proteins/drug effects , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolismABSTRACT
OBJECTIVE: The objective of this study was to determine the effect of nonspecific phosphodiesterase inhibition on transcription factor activation and tumor necrosis factor-alpha (TNF-a) production in lipopolysaccharide (LPS)-stimulated human mononuclear cells. INTRODUCTION: The production of TNF-a following LPS stimulation is one of the key steps in bacterial sepsis and inflammation. The mechanism by which phosphodiesterase inhibition alters TNF-a production in the presence of LPS remains unclear. METHODS: Human mononuclear cells were stimulated with LPS (1 µg/mL), in the presence and absence of Pentoxifylline (PTX; 20 mM), a nonspecific phosphodiesterase inhibitor. Western blotting of phosphorylated cytoplasmic I-kBa, nuclear factor-kB p65 (NF-kB), and nuclear cAMP-response element binding protein (CREB) was performed. DNA binding of NF-kB and CREB was verified by electrophoretic mobility shift assay. TNF-a levels were determined in the supernatant of stimulated cells in the presence and absence Protein kinase A inhibition by an enzyme-linked immunosorbent assay (ELISA). RESULTS: PTX was demonstrated to significantly reduce cytoplasmic I-kBa phosphorylation, nuclear p65 phosphorylation, and the DNA binding activity of NF-kB. In contrast, PTX markedly enhanced the phosphorylation and DNA binding activity of CREB. Cells concomitantly treated with PTX and LPS secreted similar levels of TNF-a in the presence and absence Protein kinase A inhibition. DISCUSSION: The increased level of cAMP that results from phosphodiesterase inhibition affects cytoplasmic and nuclear events, resulting in the attenuation of NF-kB and the activation of CREB transcriptional DNA binding through pathways that are partially Protein kinase A-independent. CONCLUSION: PTX-mediated phosphodiesterase inhibition occurs partially through a Protein kinase A-independent pathway and may serve as a useful tool in the attenuation of LPS-induced inflammation.