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 paclitaxelinduced acute and chronic thermal hyperalgesia in mice was evaluated.
Materials & Methods: 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.
Results: 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.
Conclusion: 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