There is no doubt that modern weight-loss medications have transformed the treatment of obesity, helping millions of people lose weight more effectively than ever before. However, these drugs are not without drawbacks. One of the biggest concerns is that patients often lose muscle mass along with body fat.

Now, researchers believe they may have found a way to overcome that problem. A newly discovered biological mechanism could allow the body to burn more fat while preserving muscle, potentially addressing one of the biggest limitations of current weight-loss treatments. At the center of this discovery is a protein known as MTCH2.

Scientists from the Weizmann Institute of Science, working with researchers from the University of Pennsylvania and the University of Texas, have uncovered the important role that the MTCH2 protein plays in regulating how cells use energy and store fat. According to findings published in the journal EMBO and reported by ScienceDaily, disabling this protein in human cells significantly increased the burning of both fats and carbohydrates while also reducing the formation of new fat cells.

Earlier Mouse Studies Showed Remarkable Results

The new findings build on previous research conducted in mice, where scientists made a surprising discovery. Animals lacking the MTCH2 protein in their muscles displayed greater physical fitness, improved endurance, and a strong resistance to obesity.

These findings suggested that MTCH2 could become an attractive target for future obesity treatments that improve metabolism without sacrificing muscle health.

A Surprising Discovery

Several years ago, Professor Atan Gross and his team in the Department of Immunology and Regenerative Biology at the Weizmann Institute were studying MTCH proteins when they noticed an unexpected effect.

After blocking the production of MTCH2 in mouse muscle tissue, the researchers observed major improvements in body composition. The mice developed more muscle fibers, gained protection against obesity, performed better during physical stress tests, and even showed improved heart function.

These muscle fibers consume large amounts of oxygen and are associated with better endurance and athletic performance, making the findings even more significant.

The Role of Mitochondria

The discovery led researchers to focus on mitochondria, often called the “powerhouses” of cells because they generate the energy needed for nearly every cellular function.

Mitochondria constantly change their structure. Sometimes they fuse into large interconnected networks that produce energy very efficiently. At other times they remain separated into smaller, less efficient units.

When energy production becomes less efficient, cells compensate by burning more fuel—including fats, carbohydrates, and proteins—to meet their energy demands.

After years of research, Professor Gross’s team concluded that the MTCH2 protein helps regulate this process by controlling how mitochondria fuse together, providing a possible explanation for the remarkable effects seen in mice.

Testing the Theory in Human Cells

In the latest study, led by PhD student Sabita Chaurasia, researchers used genetic engineering techniques to remove the MTCH2 protein from human cells.

The results were striking.

Without MTCH2, the normal mitochondrial network broke apart into smaller units, making energy production less efficient. As a result, the cells entered what researchers described as a state of constant energy shortage.

While this may sound harmful, it actually produced an interesting metabolic effect. Because the cells struggled to generate energy efficiently, they were forced to consume significantly more fuel to meet their energy needs.

Cells Burned More Fat

Researchers observed increased breakdown of fats, carbohydrates, and amino acids. Even more importantly, the cells changed the way they produced energy.

Normally, human cells rely heavily on carbohydrates and proteins. However, cells lacking MTCH2 shifted their metabolism and began using fat as their primary energy source, dramatically increasing fat burning.

The team also discovered another important benefit.

Previous studies had shown that women with obesity tend to have higher levels of MTCH2. This prompted scientists to investigate whether the protein also influences the creation of new fat cells.

Fewer New Fat Cells Formed

Fat cells originate from immature progenitor cells. Under the right conditions, these cells accumulate fat and mature into fully developed fat-storing cells through a process called differentiation.

When researchers removed MTCH2 from these progenitor cells, this transformation became much more difficult. As a result, fewer new fat cells were created, and overall fat storage declined.

In other words, cells lacking MTCH2 not only burned more fat but also became less capable of producing new fat-storing cells.

A Potential Future Treatment

Although the findings are still at the research stage and more studies—including clinical trials in humans—will be needed before any treatment becomes available, the discovery highlights MTCH2 as a promising target for next-generation obesity therapies.

If future research confirms these results, scientists may eventually develop treatments that help people lose fat more efficiently while preserving muscle mass and limiting the body’s ability to create new fat cells—potentially marking a major advance in the fight against obesity.