Imagine being able to erase fibromyalgia pain from you brain, making it just go away. It sounds like a dream, but - someday - scientists may actually be able to make that happen.
A team of researchers has made an important discovery about how the memory of pain is stored in the brain. Why is that important? Because the memory of pain intensifies future pain. That's something scientists have know for a long time. Every broken arm, every burn, every toothache, every surgery ... they've all formed trace memories that change how your brain responds to pain. In some of us, that leads to pain hypersensitivity.
Now researchers are saying they've found the substance responsible for forming those memories, and by blocking it, they may be able to erase pain memories and reduce hypersensitivity.
Manipulating Memories of Pain
The enzyme researchers are targeting is called PKMzeta. They say it deals with long-term memory storage in several regions of the brain and also affects how pain is processed by specialized nerves (nociceptors) in an area called the spinal cord dorsal horn (SCDH.) PMKzeta helps for connections between neurons, building pathways that activate when you experience new pain.
By blocking PKMzeta in rats, scientists were able to reverse both the pain-processing abnormality in the SCDH and hypersensitivity to movement across the skin (called mechanical allodynia, which is common in fibromyalgia.)
They concluded that PKMzeta is responsible for maintaining persistent pain and could be lead to a new type of drug for chronic pain. If so, this could finally be a drug that treats the cause of pain instead of merely covering it up.
Relevance to Fibromyalgia
This study was about chronic pain in general, not fibromyalgia specifically. However, many of the things they looked at are known to be involved in fibromyalgia, including:
- SCDH nociceptors
- Hypersensitivity to pain
- Allodynia (pain from typically non-painful stimuli)
- Pain from ischemia (impaired blood flow)
Nociceptors are specialized cells that can cause fast reactions to pain without having to first send signals to the brain and receive information back. They're what makes your hand flinch away just before you burn your fingers on the stove. If they had to communicate with the brain, they wouldn't be able to stop you.
In fibromyalgia, nociceptors can become chronically activated, which means they keep sending pain signals even when they pain should be gone. Those persistent itching, tingling, burning, stabbing pains that aren't tied to any current problem? They come from nociceptors.
"Hypersensitivity to pain" pretty much describes fibromyalgia. Something that would cause mild pain in someone else can cause moderate or severe pain in us. We're always going to be a few notches higher on the pain scale. That's due to a lowered pain threshold, which is the point at which sensation becomes painful.
Allodynia is one of those symptoms that really lets you know you have fibromyalgia. It's the pain from a loose waistband, a breeze against your skin, or a gentle touch. It's what makes your body scream when shower spray hits it or when you scratch an itch. Allodynia is a rare symptom, only showing up in a handful of conditions, most of which involve nerve damage (which fibromyalgia doesn't.) It's believed to originate in the nociceptors.
Ischemia is the medical term for a body part "falling asleep" due to restricted blood flow. Some research suggests that blood-flow problems in fibromyalgia lead to ischemia, which then becomes painful when the blood returns to the area and "wakes it up." With most people, it only happens in the feet and hands. With us, it can happen anywhere in the body.
First Steps in a Long Process
Sadly, science moves at a slow pace.† This study was done on rats, which means they still need to test the hypothesis on humans. Even if someone was working on a PKMzeta-blocking drug right now, it wouldn't likely be on the market for at least 5 years. However, someone may discover that an existing drug blocks this enzyme, or maybe that a particular supplement does. That could give us treatment options a lot sooner.
At the very least, it's good to know that work like this is being done and further validates fibromyalgia as a very real, physiological illness.
Learn more or join the conversation!
Photo © A.D.A.M.