A protein called Piezo2 may help protect the myelin sheath that insulates nerve fibers in the brain and spinal cord, offering a potential new way to prevent nerve damage in multiple sclerosis (MS). Researchers found that when this protein is missing, mice develop motor problems and abnormal myelin wrapping, and that Piezo2 levels are significantly reduced in nerve tissue from people with MS.

What Is Piezo2 and Why Does It Matter for MS?

Piezo2 is a channel protein that helps cells sense mechanical forces like pressure and stretching. While scientists have mostly studied it in the peripheral nervous system (the nerves outside the brain and spinal cord), its role in the central nervous system, particularly in oligodendrocytes (the cells that produce myelin), remained largely unknown until now.

In MS, the immune system attacks myelin, the fatty insulating layer wrapped around nerve fibers. This damage disrupts electrical signals traveling through the brain and spinal cord, leading to progressive nerve degeneration and loss of function. Current MS treatments primarily focus on slowing disease progression by suppressing the immune response, but they don't repair the underlying damage.

The new research suggests Piezo2 plays a critical role in maintaining myelin integrity rather than forming new myelin. This distinction is important because it points to a potential way to preserve existing nerve protection rather than just slow its loss.

What Did the Research Show?

A team of German researchers examined how Piezo2 functions in the optic nerve, which is commonly affected by demyelination and inflammation in MS. They engineered mice lacking Piezo2 specifically in oligodendrocytes and compared them to normal mice.

The findings were striking:

• Motor Function: Mice without Piezo2 developed age-related motor problems, with effects appearing earlier and more severely in female mice.
• Myelin Structure: Myelin layers in Piezo2-deficient mice were loosely wrapped rather than tightly packed, particularly around small nerve fibers vulnerable to demyelination in MS.
• Nerve Fiber Integrity: The nerve fibers themselves remained intact, indicating the problem was specifically with myelin, not the underlying axons.

When researchers examined human nerve tissue, the difference was clear. In tissue from people without MS, about 73% of myelin-producing oligodendrocytes expressed the PIEZO2 gene. By contrast, only about 50% of these cells expressed it in tissue from people with MS, with expression progressively decreasing toward lesion areas.

How Could This Lead to New MS Treatments?

The discovery opens a new avenue for MS therapy development. Rather than focusing solely on immune suppression, researchers could potentially target Piezo2 signaling to preserve myelin integrity and prevent further nerve damage. This approach aligns with growing interest in remyelination therapies, which aim to repair or replace damaged myelin.

One company already pursuing this myelin-repair strategy is Imunexus, an Australian biotech firm preparing for a stock exchange listing. The company is developing IMX39, a first-in-class biologic therapy for MS designed to repair the damaged myelin sheath rather than just manage symptoms. Preclinical animal studies have shown evidence of myelin repair and improvements in mobility, and the company plans to begin Phase I clinical trials following its proposed listing.

"If there's an opportunity to reverse the disease, that's pretty fabulous," said Philippa Lewis.

Philippa Lewis, Chief Executive Officer at Imunexus

However, researchers emphasize that more work is needed. The team concluded that "future work will be required to validate these mechanisms across additional models and to determine whether targeting Piezo2 signaling can restore myelin integrity and improve functional outcomes in demyelinating disease".

Future Research Directions for Piezo2-Targeted Therapies

• Mechanism Validation: Scientists need to test Piezo2 signaling in additional animal models to confirm the findings hold across different experimental systems and disease contexts.
• Human Tissue Studies: Researchers must examine how Piezo2 expression changes in human MS lesions at different stages to understand the protein's role throughout disease progression.
• Functional Restoration: Future studies will determine whether activating or enhancing Piezo2 signaling can not only preserve myelin but also restore some lost nerve function in people with MS.

The research represents an important shift in MS treatment strategy. For decades, the field has focused on halting immune attacks. Now, scientists are increasingly interested in repairing the damage those attacks cause. If Piezo2-targeted therapies prove effective in human trials, they could offer MS patients something current treatments cannot: the possibility of reversing neurological damage rather than simply slowing its progression.