Estudo da atividade antinoceptiva e anti-inflamatoria protótipos de fármacos

Abstract

This work was conducted to evaluate the activity anti-inflammatory and antinocieptive two series of derivatives of N-acilidrazonas (NAH) rationally designed and synthesized by LASSBio® UFRJ. The first series consists of four compounds, being two metal complexes generated from the coordination of prototypes LASSBio-1064 and LASSBio-466 and second prototype LASSBio-1064 and LASSBio-466. The second series comprised eight derivatives, designed as structural analogues of piroxicam. Were performed nociception models of functional chemical (writhing induced by acetic acid 0.1 N, formalin test), thermal nociception (hot plate test), cell migration assay (peritonitis induced by zymosan A and / or induced by carrageenin) assay evaluation of inhibition of COX-1/COX-2. All compounds and standards were administered 40 min before starting the test (p.o) at a dose of 100 mmol / kg. In the first series, Animal constriction induced by acetic acid was inhibited by all the compounds studied, highlighting the [Zn(LASSBio-466)H2O]2 and H2LASSBio-1064 that inhibited (p˂0.01) at 82.7 % (p˂0.01) and 81.3% (p˂0.01) the number of writhes, as the standard drug (dipyrone) inhibited 77.7% (p˂0.01). In the first phase of the formalin test H2LASSBio-466 and H2LASSBio-1064 reduced the latency time to lick 53.1% (p ˂ 0.05) and 46.5% (p˂0.01), respectively. In the second phase of the test compounds H2LASSBio-1064 and [Zn(LASSBio-466)H2O]2 reduced the latency time to lick at 48.5% (p˂0.05) and 37.3% (p˂0.05), respectively. All compounds showed levels of inhibition of peritonitis induced by zymosan comparable or superior to indomethacin (drug standard). In the second series, the compounds were active in the assay of writhing induced by acetic acid highlighting the LASSBio-1638, LASSBio-1604 and LASSBio-1639 inhibited the contortions that abdmoniais in 84.0% (p˂0.01), 82.7% (p˂ 0.01) and 90.4% (p˂ 0.01), respectively, whereas piroxicam (drug standard), inhibited by 95.4% (p˂0.01) . In the formalin test, only LASSBio-1617 significantly inhibited the nociceptive activity in the first stage by 58.2% (p<0.01). In the second phase the LASSBio-1637, LASSBio-1638 inhibited the nociceptive activity in 60.0% (p<0.05) and 54.2% (p<0.05), respectively, and piroxicam inhibited 53.9 % (p<0.01). In models of acute inflammation, the compounds showed inhibitory activity against cell migration similar to or greater than the piroxicam. In the trial of carrageenan-induced acute peritonitis compounds LASSBio-1604LASSBio-1637, LASSBio-1638 and LASSBio-1639 inhibited cell migration by 74.2% (p˂ 0.01), 73.2% (p˂0.01), 77.6% (p˂ 0.01) and 81.8% (p ˂ 0.01), respectively, where as piroxicam inhibited by 25.5% (p˂0.01). The compounds LASSBio-1637, LASSBio-1638-1639 and LASSBio highlighted in the testing of acute peritonitis induced by zymosan A, inhibiting cell migration in 78.6% (p˂0.01), 81.2% (p ˂ 0.01) and 82.7% (p ˂ 0.01), showing that, in this essay, more active than piroxicam (57.3%). LASSBio-1604 and LASSBio-1617 inhibited the enzyme COX in vitro, presenting, respectively, IC50 values of 0.22 M and 0.28 M for inhibition of COX-1 and 0.24 M and 0.26 M for inhibition of COX-2. Pharmacological Evaluation results suggest that in the first series, the coordination of zinc (II) is a good strategy to improve the antinociceptive activity of the compound H2LASSBio-466 associated with inflammatory pain, and in the second series, all compounds exhibit antinociceptive and anti-inflammatory similar or superior to piroxicam.