A little-known protein could be a major culprit in type 2 diabetes
Scientists have discovered that a buildup of a protein called Miro1 may be a hidden driver of insulin resistance in Type 2 diabetes, with preclinical experiments showing that removing it restores the muscles’ response to insulin. Exercise was also found to lower Miro1 levels in people with diabetes, revealing a potential new pathway for treating the disease.
Key points
- Researchers found higher levels of the protein Miro1 in skeletal muscle of people with Type 2 diabetes.
- Removing Miro1 restored insulin response in preclinical experiments, and exercise lowered Miro1 levels in patients.
- The study, published in Nature Communications, points to Miro1 as a possible new treatment target.
- A randomized trial compared aerobic exercise with standard medical care in people with obesity and Type 2 diabetes.
Researchers have identified a protein called Miro1 that may play an important role in Type 2 diabetes by interfering with the body's response to insulin, according to findings published in Nature Communications. The protein was found at higher levels in the skeletal muscles of people with the disease.
In preclinical experiments, removing Miro1 restored the muscles' response to insulin. The team also found that exercise lowered Miro1 levels in people with Type 2 diabetes, offering insight into how physical activity improves insulin sensitivity.
How Miro1 affects muscle
Miro1 (Mitochondrial Rho GTPase1) sits on the outer membrane of mitochondria, the cell structures that produce energy. Researchers believe excessive amounts of the protein may interfere with how muscles respond to insulin, making blood sugar harder to regulate.
The team studied Miro1 in laboratory cells, preclinical models and people with Type 2 diabetes. The results showed that Miro1 buildup impaired the muscles' insulin response, and removing it in preclinical models restored responsiveness.
Insulin resistance in muscle is at the heart of Type 2 diabetes, and its molecular causes have remained frustratingly unclear.
— Dr. John P. Kirwan
Exercise and next steps
In a randomized controlled trial of participants with obesity and Type 2 diabetes, researchers compared aerobic exercise with standard medical care. The exercise group saw Miro1 levels in muscle decline, alongside improvements in insulin sensitivity and the muscles' capacity to produce energy.
Scientists still need to establish whether directly targeting Miro1 can produce safe and effective treatments. Senior author Dr. John P. Kirwan, now executive director of the OU Health Harold Hamm Diabetes Center at the University of Oklahoma, plans to continue the research there.
