EFFECT OF ADMINISTRATION OF NANO-ZINC OXIDE ON THERMAL HYPERALGESIA INDUCED BY ACUTE AND CHRONIC TREATMENT OF PACLITAXEL IN MICE

Multiple evidences available about zinc oxide nanoparticles (nano-ZnO) ameliorative effects on neuroinflammation that worked in contrast to mechanisms activate with paclitaxel. In this study, effect of local and intraperitoneal application of nano-ZnO on paclitaxel-induced acute and chronic thermal hyperalgesia in mice was evaluated.
Adult male mice (35-40 g) were divided into acute and chronic studies categories. Acute groups received paclitaxel (20 mg/kg, single dose, i.p.) and nano-ZnO (100 and 500 µg, intraplantar) with paclitaxel and Chronic groups received nano-ZnO (0.1, 1, 10, mg/kg, i.p.) and (4.5 mg/kg, i.p.) for 4 days. The control group received paclitaxel (4.5 mg/kg, i.p.) for 4 days. Paw withdrawal latency from hot (46ºC) and cold (2-3ºC) water was evaluated after each treatment.
Paclitaxel caused hot and cold thermal hyperalgesia in chronic regimen but only induced hot thermal hyperalgesia in acute treatment regimen. In mice, treatment with nano-ZnO significantly and dose-dependently suppressed cold and hot hyperalgesia induced by chronic paclitaxel treatment and also reduced hot thermal hyperalgesia in acute paclitaxel treated.
The results indicate that nano-ZnO can reduce hot thermal neuropathic hyperalgesia induced by acute and chronic models of paclitaxel hyperalgesia. The efficacy of nano-ZnO treatment on acute and chronic models of paclitaxel-induced painful thermal hyperalgesia can provide useful evidence for further exploring in clinical researches on it.