Neuropathic pain: The sea provides a new hope of relief

August 04, 2009

A compound initially isolated from a soft coral (Capnella imbricata) collected at Green Island off Taiwan, could lead scientists to develop a new set of treatments for neuropathic pain - chronic pain that sometimes follows damage to the nervous system. Currently this form of pain is very poorly controlled by the usual analgesics (aspirin like drugs (NSAIDS) or even opioids like morphine) and novel treatments are urgently required. The conclusion of a paper published today in the British Journal of Pharmacology is that this new compound could be a candidate.

Recent research suggests inflammation in the nervous system is a major causative factor for this condition. Inflammation activates supporting cells, such as microglia and astrocytes, that surround the nerve cells. These activated cells release compounds called cytokines that can excite nerves carrying pain sensation (nociceptive pathways) and cause the person to experience mildly uncomfortable stimuli as very painful (hyperalgesia), or stimuli that would normally induce no discomfort at all as painful (allodynia). Thus, cold drafts or lightly brushing the skin can produce intense pain, severely affecting the person's quality of life.

The treatments that give some relief to some patients are a very mixed bunch, nearly all found empirically and with many other effects. Amitriptyline, an anti depressant now used for urinary incontinence, has given relief in neuropathic pain; similarly, two drugs designed for treating epilepsy - gabapentin and pentagabalin have also proved effective for some sufferers. However, many patients do not respond to these currently available drugs.

"New, effective and safe painkillers are urgently needed for patients with neuropathic pain," says Dr Zhi-Hong Wen, who played a key role in a research study searching for novel compounds that have potential for use in pain relief. Dr Wen and colleagues work at the Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Taiwan.

Although the chemical they studied, capnellene, was originally isolated in 1974, it is only recently that scientists have started to appreciate its potential. Capnellene is interesting because its structure is very different from pain-relieving drugs currently in use. Initial experiments suggested that it may have pain-relieving properties. Working with Yen-Hsuan Jean MD, PhD and other colleagues, Dr Wen tested capnellene and a second very similar compound, in isolated microglial cells and in experimental models of the condition in rats.

They found that the compounds significantly reduced pain-related activities in isolated microglia, and that these compounds also significantly reversed hyperalgesic behaviour in the experimental rats.

"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," says Dr Wen.

"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," he adds.
-end-


Wiley

Related Chronic Pain Articles from Brightsurf:

Researchers are developing potential treatment for chronic pain
Researchers from the University of Copenhagen have developed a new way to treat chronic pain which has been tested in mice.

Molecular link between chronic pain and depression revealed
Researchers at Hokkaido University have identified the brain mechanism linking chronic pain and depression in rats.

How chikungunya virus may cause chronic joint pain
A new method for permanently marking cells infected with chikungunya virus could reveal how the virus continues to cause joint pain for months to years after the initial infection, according to a study published Aug.

Gastroesophageal reflux associated with chronic pain in temporomandibular joint
Gastroesophageal reflux (GERD) is associated with chronic, painful temporomandibular disorder -- pain in the temporomandibular joint -- and anxiety and poor sleep contribute to this association, according to a study in CMAJ.

One step closer to chronic pain relief
While effective drugs against chronic pain are not just around the corner, researchers from Aarhus University, Denmark, have succeeded in identifying a protein as a future potential target for medicinal drugs.

Gut bacteria associated with chronic pain for first time
In a paper published today in the journal Pain, a Montreal-based research team has shown, for the first time, that there are alterations in the bacteria in the gastrointestinal tracts of people with fibromyalgia.

Nearly 5.4 million cancer survivors suffer chronic pain
A new report finds about one in three cancer survivors (34.6%) reported having chronic pain, representing nearly 5.4 million cancer survivors in the United States.

New opioid speeds up recovery without increasing pain sensitivity or risk of chronic pain
A new type of non-addictive opioid developed by researchers at Tulane University and the Southeast Louisiana Veterans Health Care System accelerates recovery time from pain compared to morphine without increasing pain sensitivity, according to a new study published in the Journal of Neuroinflammation.

New target for chronic pain relief confirmed by scientists
A research group at Hiroshima University observed a potential new target for chronic pain treatment.

Menopause symptoms nearly double the risk of chronic pain
In addition to the other health conditions affected by estrogen, it has also been shown to affect pain sensitivity.

Read More: Chronic Pain News and Chronic Pain Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.