Anti-inflammatory and antinociceptive effects, and safety toxicological profile of a new paracetamol analog, LQFM291.

In the scope of a research program with the goal of developing treatments for inflammatory diseases, the pharmacological evaluation of LQFM291, designed by molecular hybridization from butylated hydroxytoluene and paracetamol, was described. The antioxidant profile of LQFM291 was evaluated by electrochemical measurement. Also, acute or repeated treatments with equimolar doses to paracetamol were used to evaluate the antinociceptive and/or anti-inflammatory activities of LQFM291 in animal models. The toxicologic potential of LQFM291 was also evaluated and compared to paracetamol through biochemical and histopathological analysis after the repeated treatment schedule. As a result of the acute treatment, paracetamol showed a similar antinociceptive effect in formalin test compared to LQFM291. Whereas, after the repeated treatment, when carrageenan-induced hyperalgesia and edema tests were performed, paracetamol showed a delayed antinociceptive and anti-inflammatory effect compared to LQFM291. Furthermore, as other advantages the LQFM291 showed a high redox capacity, a gastroprotective activity and a safety pharmacological profile without any liver or kidney damage. These effects can be related to the prevention of oxidative stress by reduction of protein and lipid peroxidation in gastric tissue, maintenance of glutathione levels in hepatic homogenate, and a systemic reduction of pro-inflammatory cytokine levels, which may characterize the LQFM291 as a more viable and effective alternative to relief pain and inflammatory signs in patients with chronic disorders.

Mechanisms involved in the antinociceptive and anti-inflammatory effects of a new triazole derivative: 5-[1-(4-fluorophenyl)-1H-1,2,3-triazol-4-yl]-1H-tetrazole (LQFM-096).

The aim of this study was to design, synthesize and evaluate the potential analgesic and anti-inflammatory effects of 5-[1-(4-fluorphenyl)-1H-1,2,3-triazol-4-yl]-1H-tetrazole-(LQFM-096: a new triazole compound) as well as to elucidate its possible mechanisms of action. The oral administration of LQFM-096 (10, 20 or 40 mg/kg) decreased the number of writhing in mice. At the dose of 20 mg/kg, LQFM-096 reduced the licking time at both neurogenic and inflammatory phases of the formalin test. Pretreatment with naloxone (3 mg/kg) and glibenclamide (3 mg/kg) attenuated the antinociceptive effect of LQFM-096 in the first phase of the formalin test. At the dose of 20 mg/kg, LQFM-096 also decreased the licking time in the acidified saline-induced and capsaicin-induced nociception. This effect was blocked by naloxone (3 mg/kg) pretreatment prior to the administration of LQFM-096. In addition, LQFM-096 inhibited hyperalgesia induced by carrageenan and PGE2. Naloxone (3 mg/kg) attenuated the effect of LQFM-096 through disinhibition of PGE2-induced hyperalgesia. The anti-inflammatory effect of LQFM-096 was demonstrated in carrageenan-induced oedema or pleurisy as well as CFA-induced arthritis. The hyperalgesia and cellular migration in CFA-induced arthritis were reduced significantly. Altogether, these findings suggest antinociceptive effect of LQFM-096 and implicate the modulation of ASICs/TRPV1 channels by opioid/KATP pathway. The anti-inflammatory effect of LQFM-096 was mediated by a reduction in oedema, leukocytes migration, TNF-α, PGE2 levels and myeloperoxidase activity.