Spearmint (Mentha spicata L.) essential oil from tipaza (Algeria): in vivo anti-infl ammatory and analgesic activities in experimental animal models

Introduction: Although analgesic and nonsteroidal anti-infl ammatory drugs (NSAIDs) are usually used to treat a diversity of illnesses, their administration is linked with acute kidney injury and gastrointestinal side eff ects. The research of new biomolecules and natural products is still needed such as medicinal plants. Aims: The present research was aimed to investigate, for the fi rst time, the anti-infl ammatory and anti-nociceptive eff ects of spearmint essential oil (SEO) in mouse models of acute infl ammation and pain. Materials and Method: Chemical analysis of SEO was done by gas chromatography. The anti-infl ammatory activity was tested using two models of acute infl ammation namely carrageenan-induced paw edema and xylene-induced ear edema. Histological examination of both non-infl amed and infl amed tissues was evaluated. The anti-nociceptive activity was tested using the pain model induced by acetic acid. Results: The main constituent of the SEO was found to be carvone (52.60%). The SEO exhibited a promising anti-infl ammatory eff ect as demonstrated by statistically signifi cant (p<0.05) inhibition of paw volume by 77.24% at the dose of 20 μL/kg and 65.87% at the dose of 200 μL/kg. Furthermore, topical administration of the SEO inhibited xylene-induced ear edema in comparison with the control group (p<0.05). The higher dose (200 μL /kg) signifi cantly (p<0.001) reduced xylene-induced ear edema which was similar to that observed with positive control (ketoprofen). The pathological analysis of the paws and ears revealed that SEO was capable of reducing cellular infi ltration and subcutaneous edema. Else, the SEO produced signifi cant anti-nociceptive activity (p<0.001) at higher dose by inhibiting spontaneous nociception. Conclusion: These results support the use of SEO in the development of pharmaceuticals for the management of infl ammation and pain