Beyond GLP-1: A New Route to Appetite Control?

Key takeaways

• Stanford researchers used a computational tool to identify BRP, a naturally occurring peptide that reduced food intake in mice and minipigs.

• A single injection reduced food consumption by up to 50% over the following hour. Daily treatment for two weeks also promoted weight loss in mice, primarily from fat rather than muscle.

• BRP appeared to activate different brain pathways from semaglutide, suggesting another possible route to appetite regulation.

• These are animal findings—not evidence of a safe, effective human treatment. “Naturally occurring” does not mean proven safe.

A small molecule with a striking effect

The body contains countless protein fragments. Some are biological leftovers; others carry powerful instructions.

Stanford researchers set out to find overlooked fragments that might regulate appetite. Their search identified BRP, a peptide just 12 amino acids long.

When injected into mice and minipigs before feeding, BRP reduced food intake by up to half during the next hour.

That is a striking short-term response. But suppressing one meal is different from producing sustained, healthy weight loss—so the researchers tested repeated treatment.

The more interesting result was what the mice lost

After 14 days of daily injections, treated mice lost an average of approximately 3 grams. Untreated mice gained approximately 3 grams.

Nearly all the lost weight came from fat rather than muscle. The animals also showed improvements in glucose and insulin tolerance, measures of how effectively the body handles blood sugar.

For healthy aging, composition matters: a lower number on the scale is not the same as losing fat while preserving the tissue that supports strength and mobility.

Still, preserving muscle mass over two weeks does not establish preserved strength, long-term function, or the same result in people.

How researchers found it

The team developed an algorithm called Peptide Predictor to search roughly 20,000 human protein-coding genes for potential hormone-like molecules.

They focused on proteins that could be cut by an enzyme involved in producing several known hormones, including GLP-1. After narrowing the search, they tested 100 candidate peptides in laboratory-grown nerve cells.

BRP stood out for its strong effect on neuronal activity.

The computational tool helped identify where to look. The experiments—not the algorithm alone—established that the peptide had biological effects.

Not simply another version of GLP-1

BRP appeared to act more selectively in the hypothalamus, a brain region involved in hunger and energy regulation. It activated different neuronal pathways from those engaged by semaglutide.

That distinction raises the possibility of suppressing appetite without reproducing all the effects of existing medications.

Researchers found no significant changes in several monitored measures, including movement, water consumption, and fecal output.

But “no changes in the measures tested” is not the same as “no side effects.” Animal experiments cannot establish whether people would experience nausea, digestive problems, or other complications.

Calling BRP a “natural” alternative also skips an important detail: the animals received injections. This was not a food, supplement, or dietary strategy.

What still needs to happen

Researchers still need to identify the receptor that recognizes BRP and investigate ways to make its effects last longer.

Human trials would then need to establish appropriate dosing, safety, effectiveness, and whether the apparent muscle-sparing benefit translates.

There is also a commercial interest to disclose: two researchers are named inventors on related patents, and senior author Katrin Svensson cofounded a company developing the approach.

The takeaway

BRP offers an intriguing possibility: appetite regulation through a different biological pathway, with early animal evidence of fat loss and muscle preservation.

The next question is not whether it can match a headline. It is whether those advantages survive longer experiments and carefully controlled human testing.

References:

1. Laetitia Coassolo, Niels B. Danneskiold-Samsøe, Quennie Nguyen, Amanda Wiggenhorn, Meng Zhao, David Cheng-Hao Wang, David Toomer, Jameel Lone, Yichao Wei, Aayan Patel, Irene Liparulo, Deniz Kavi, Lianna W. Wat, Saranya Chidambaranathan Reghupaty, Julie Jae Kim, Tina Asemi, Ewa Bielczyk-Maczynska, Veronica L. Li, Maria Dolores Moya-Garzon, Nicole A. J. Krentz, Andreas Stahl, Danny Hung-Chieh Chou, Liqun Luo, Katrin J. Svensson. Prohormone cleavage prediction uncovers a non-incretin peptide. Nature, 2025; 641 (8061): 192 DOI: 10.1038/s41586-025-08683-y