2005 - 02

Pharmacol Biochem Behav. 2005 Feb;80(2):327-32. Epub 2004 Dec 23.

Subanalgesic doses of dexketoprofen and HCT-2037 (nitrodexketoprofen) enhance fentanyl antinociception in monoarthritic rats.

Gaitan G, Herrero JF. Departamento de Fisiologia, Facultad de Medicina, Campus Universitario, Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain.

Subanalgesic doses of the non-steroidal antiinflammatory drugs (NSAID) dexketoprofen trometamol and nitroparacetamol (NCX-701) enhance mu-opiate fentanyl effect in acute nociception. It is not known if a similar combination of drugs is effective in situations of spinal cord sensitization. The aim of this study was to assess if the enhancement of fentanyl antinociception can be observed in carrageenan-induced monoarthritis, when combined with dexketoprofen (DKT) or nitrodexketoprofen (HCT-2037). Withdrawal reflexes were recorded as single motor units in male Wistar rats anesthetized with alpha-chloralose. Fentanyl was studied alone and in the presence of 0.4, 0.8 micromol/kg of DKT or 0.3 micromol/kg of HCT-2037. In responses to noxious mechanical stimulation, the ID50 of fentanyl was enhanced twofold by 0.8 micromol/kg DKT and more than fourfold by HCT-2037 and no significant recovery was observed 45 min later. DKT 0.4 micromol/kg was, however, very little effective. The opioid antagonist naloxone did not reverse the effect. Enhancement of fentanyl effect on wind-up was only observed with HCT-2037 but not with DKT. We conclude that the combined administration of subanalgesic doses of dexketoprofen derivatives, specially its nitroderivative, and the mu-opiate fentanyl is an effective antinociceptive therapy in situations of articular inflammation involving a naloxone-independent mechanism of action.



J Neurochem. 2005 Feb;92(4):895-903.

Nuclear receptor peroxisome proliferator-activated receptor-gamma is activated in rat microglial cells by the anti-inflammatory drug HCT1026, a derivative of flurbiprofen.

Bernardo A, Ajmone-Cat MA, Gasparini L, Ongini E, Minghetti L. Department of Cell Biology and Neuroscience, Istituto Superiore di Sanita, Rome, Italy.

The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is constitutively expressed in primary cultures of rat microglia, the main population of brain resident macrophages, and its ligand-dependent activation leads to the repression of several microglial functions. A few non-steroidal anti-inflammatory drugs (NSAIDs), e.g. indomethacin and ibuprofen, show PPAR-gamma agonistic properties. It has been proposed that PPAR-gamma activation contributes to the potential benefits of the long-term use of certain NSAIDs in delaying the progression of Alzheimer's disease (AD). Previous data have shown that the NSAID HCT1026 [2-fluoro-alpha-methyl(1,1'-biphenyl)4-acetic acid-4-(nitrooxy)butyl ester], a derivative of flurbiprofen which releases nitric oxide (NO), reduces the number of reactive microglial cells in a variety of models. This evidence together with the chemical analogy with ibuprofen led us to investigate whether flurbiprofen and HCT1026 interact with PPAR-gamma and interfere with microglial activation. We found that a low concentration (1 microm) of HCT1026, but not flurbiprofen, activated PPAR-gamma in primary cultures of rat microglia, with kinetics similar to those of the synthetic agonist ciglitazone. The PPAR-gamma antagonist GW9662 (2-chloro-5-nitrobenzanilide) prevented the activation of PPAR-gamma by HCT1026. Interestingly, unlike other NSAIDs that activate PPAR-gamma at concentrations higher than those required for cyclooxygenase inhibition, HCT1026 activated PPAR-gamma and inhibited prostaglandin E2 synthesis at the same low concentration (1 microm). The results suggest that HCT1026 may exert additional anti-inflammatory actions through PPAR-gamma activation, allowing a more effective control of microglial activation and brain inflammation.