Mentha longifolia L. (Lamiaceae), a traditional medicinal herb, has been highly valued for exhibiting antimicrobial, antioxidant and antispasmodic properties.For the first time, the synergetic anti-inflammatory effects of deuterium depleted water (DDW) and M. longifolia essential oils (ML) were investigated in experimental sepsis.Fifty Wistar rats were divided into 5 groups (n = 10): negative control (laparotomy), CLP, treatment groups including the combination of DDWs (15 and 30 ppm) and ML (100 mg/kg b.w) and indomethacin. At 24 h after CLP induction, lipid peroxidation (LP), glutathione (GSH), glutathione in S-transferases (GST), ferric reducing ability of plasma (FRAP), myeloperoxidase (MPO), prostaglandin E2 (PGE2), and COX-2 expression were determined in the plasma and liver tissues.Compared with the CLP group, the administration of DDWs and ML significantly (p < 0.05) prevented the increase of LP, COX-2 and PGE2 levels and liver enzymes. Additionally, the decreased levels of FRAP and GSH induced by sepsis were remarkably (p < 0.05) risen by the administration of DDWs and ML in comparison to the CLP group. However, no significant (p > 0.05) differences were observed regarding GST, ALP and bilirubin levels. Our results also proved the synergistic anti-inflammatory activities of the DDWs and ML. The anti-inflammatory effects of the DDWs and ML were confirmed by histopathological studies.The combination of DDWs and ML exerted synergistic anti-inflammatory activity against CLP-induced sepsis possibly through modulating oxidative stress/antioxidant parameters.
