The investigators previously found that the administration of
lemnalol, a natural marine compound isolated from the Formosan soft coral Lemnalia cervicorni, produced anti-inflammatory and
analgesic effects in
carrageenan-injected rats. Recently, several studies have demonstrated that the development and maintenance of
neuropathic pain are accompanied by releasing of proinflammatory mediators from activated glial cells in the spinal cord. In this study, we investigated the antinociceptive properties of
lemnalol, a potential anti-inflammatory compound, on chronic constriction injury (CCI) in a well-established rat model of
neuropathic pain. Our results demonstrated that a single intrathecal administration of
lemnalol (0.05-10 μg) significantly attenuated CCI-induced
thermal hyperalgesia and
mechanical allodynia, 14 days postsurgery. Furthermore, immunohistofluorescence analyses showed that
lemnalol (10 μg) also significantly inhibits CCI-induced upregulation of microglial and astrocytic immunohistochemical activation markers in the dorsal horn of the lumbar spinal cord. Double immunofluorescent staining demonstrated that
intrathecal injection of
lemnalol (10 μg) markedly inhibited spinal proinflammatory mediator
tumor necrosis factor-α expression in microglial cells and astrocytes in neuropathic rats. Collectively, our results indicate that
lemnalol is a potential therapeutic agent for
neuropathic pain, and that further exploration of the effects of
lemnalol on glial proinflammatory responses is warranted.