Marine Compound May Provide New Treatment for Neuropathic Pain

A compound that was initially isolated from a soft coral on an island off of Taiwan may enable scientists to create a new treatment for neuropathic pain.

Researchers in the Department of Marine Biotechnology and Resources at National Sun Yat-Sen University in Taiwan found that capnellene, the chemical isolated from the soft coral Capnella imbricata, “significantly reduced pain-related activities in isolated microglia, and that these compounds also significantly reversed hyperalgesic behaviour in the experimental rats.”

Treatment for neuropathic pain is limited and the treatments that do exist work poorly for controlling symptoms. The discovery of capnellene as an analgesic indicates a new candidate for treating neuropathic pain, the researchers said.

The researchers examined the effects of capnellene (GB9) and its acetylated derivative, GB10, “on the expression of inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) in interferon-γ (IFN-γ)-stimulated mouse microglial BV2 cells,” according to a study published in the British Journal of Pharmacology.

The key results of the study showed that, “in BV2 cells, GB9 and GB10 inhibited the expression of iNOS and COX-2, stimulated by IFN-γ.” In addition, “intrathecal administration of GB9 and GB10 inhibited CCI-induced nociceptive sensitization and thermal hyperalgesia in a dose-dependent manner” and “intraperitoneal injection of GB9 inhibited CCI-induced thermal hyperalgesia and also inhibited CCI-induced activation of microglial cells and up-regulation of COX-2 in the dorsal horn of the lumbar spinal cord ipsilateral to the injury.”

"To provide better quality of life, we need new drugs that can act rapidly and have specific functions with low side effects. Moreover, we need better management for chronic pain conditions," said Dr Zhi-Hong Wen, one author of the study. "Today there are few pharmacological agents that can help people suffering from neuropathic pain, but we believe that these marine-derived compounds could lead to the development of a new range of drugs of great potential.”