New form of Botox relieves chronic pain – in mice

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This is not just for fine lines and wrinkles: Botox is promising as a treatment for chronic pain. Or, rather, botulinum toxin that is used commercially to erase the signs of aging is also being studied as a potential alternative to opioid drugs.

A new article in Science shows that a single dose of botulinum toxin, injected into the vertebral cavity, caused several weeks of pain relief from chronic and neuropathic pain – in mice. The researchers have developed a new form of neurotoxin to selectively disable the neurons responsible for pain in the spinal cord. It worked for 23 days without killing nerve cells and without causing toxicity, according to the study.

"At the moment, opioids are the norm for treating pain – but they are at the origin of an addiction epidemic – the United States right now," said Maria Maiarù, Lead author of the study and researcher at the Department of Cell and Developmental Biology at University College London. "What we provide is an opioid-free treatment for chronic pain."

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But if Maiarù's work is enticing, it is still too early to tackle the epidemic. Opioids with Botox. research say.

"It's interesting and hopeful," said Dr. Michael Andary, a professor in the Department of Physical Medicine and Rehabilitation at the Michigan State University College of Osteopathic Medicine

Vijay Babu , medical director of the Clinic of Spine and Pain of Florida, agrees: "The establishment of results in the field of opioid epidemic seems to be a little away for me, "he said," models for humans: There are very few patterns of pain that translate across species, "said Andary." And Babu is not convinced that animal models are reliable representations of chronic pain: it is difficult to disentangle the acute pain of chronic pain in mice Babu said that it would take a lot of measures to move from acute pain treatment in mice the treatment of chronic pain in humans. 19659003] Babu and Andary said that injecting botulinum toxin into the intrathecal space – that is, into the spinal cbad.

But the study is biochemically very interesting, they said, and if Maiarù's work is successful, it could have significant clinical implications.

The work is far from the clinic: Maiarù hopes to spend mice and test the drug in dogs with osteoarthritis. This could help prove the duration of treatment, since arthritic dogs will already be in demonstrable pain.

Although the study indicates 23 days of pain relief in mouse models, Maiarù is confident that animals would benefit from injections for up to three months. The question, she said, is that the nature of the design of the trial limited the time during which pain tolerance could be studied in mice. Thanks to the UK's ethical regulations on animal testing, mice can stay in pain for about a month only – so researchers have not been able to badess the effect injection of botulinum toxin in animals

. neurotoxin produced by the bacterium Clostridium botulinum – the virus responsible for botulinum disease. Cosmetically, it works by preventing the injected muscles from contracting, thus appearing smooth. It has been marketed by drug giant Allergan for a variety of indications; the synthetic form of the toxin has been specifically developed to target pain – by attaching a protein targeting the same receptor used by morphine in the spinal cavity.

This is not the first time that Botox is used for pain. far from thinking that he could have clinical use in chronic pain. It is already approved by the Food and Drug Administration for neck spasms and as a migraine therapy, along with other indications like bladder pain and excessive sweating. It is used off-label for many different conditions – ranging from very cold hands to premature ejaculation.

Biotech Correspondent

Meghana covers biotechnology and writes the Readout newsletter.