Partial liquid ventilation with various types of
perfluorocarbon (PFC) has been shown to be beneficial in treating
acute lung injury, a clinical outcome that may involve the anti-inflammatory activity of PFC.
FC-77 is a type of PFC with relatively higher vapor pressure and evaporative loss than other PFCs during
partial liquid ventilation. Overproduction of
nitric oxide (NO) by
inducible nitric oxide synthase (iNOS) has been proposed to play a crucial role in the pathogenesis of inflammatory diseases. However, whether the iNOS/NO pathway is affected by
FC-77 is unknown. Thus, the aim of this study was to investigate whether
FC-77 inhibits iNOS expression and NO production in
lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. We found that treatment with
FC-77 significantly attenuated LPS-induced iNOS expression/activity and production of NO and
reactive oxygen species (ROS).
FC-77 also attenuated LPS-induced pro-inflammatory
cytokine formation, but enhanced
interleukin-10 production. Furthermore, the LPS-induced degradation of cytosolic
IkappaB-alpha and activation of nuclear
transcription factor-kappaB (
NF-kappaB) were also inhibited by
FC-77. In conclusion, the present study is the first to demonstrate that
FC-77 decreases LPS-induced NO production in macrophages, which may be associated with the suppression of pro-inflammatory
cytokines, and ROS production, as well as
NF-kappaB activation. These results also provide a novel explanation for its anti-inflammatory activity.