Roberto C Debom, Margarete M Trachez, Gisele Zapata Sudo, Jaqueline S da Silva, Kesley M Oliveira, Ariel L Garcia, Lidiane M Godoy, Ogari C Pacheco and Roberto T Sudo
Diabetic Peripheral Neuropathic Pain (DPNP) has been attributed to abnormal glucose metabolism and oxidative stress. It is among the most common consequence of chronic diabetes and is treated with antiepileptic compounds, antidepressants, and opioids. However, many patients with DPNP experience lack of treatment efficacy and/or adverse secondary effects that impair quality of life. Here we report the identification of a novel agonist targeting neuronal nicotinic Acetylcholine Receptors (nAChRs) that may alleviate neuropathic pain. A new pyrazole analogue, Cris-104, has been observed to produce antinociceptive activity in acute and chronic pain models. In the present study, Cris-104 effects on thermal hyperalgesia and mechanical allodynia were evaluated in a rat DPNP model. Oral administration of Cris-104 (35 mg.kg-1.day-1 for 7 days) induced antinociception as evidenced by reductions in thermal hyperalgesia and mechanical allodynia in DPNP rats. The mechanism of antinociception cannot be attributed to a diabetes-alleviating effect because blood glucose levels were not reduced significantly by the treatment. The analgesia could be mediated by activation of nAChRs since Cris-104 is a specific ligand for the nAChR. In conclusion, Cris-104 is a compound with potential to be used as a pain reliever in patients with DPNP.