Snake urine may hold the secret to ending the pain of gout and kidney stones

If you’ve never kept a reptile before, you may be surprised to learn that many of them actually “urinate” in crystal form. In a study published in Journal of the American Chemical SocietyResearchers examined the solid urine of more than 20 different species of reptiles, and found that they all contained tiny balls made of uric acid. This discovery highlights how reptiles evolved a unique way to safely store and remove waste in crystalline form. The findings could also lead to new ways to treat human conditions associated with uric acid buildup, such as kidney stones and gout.

How reptiles provide water with solid waste

Every living organism needs to eliminate waste, and reptiles are no exception. In humans, the body gets rid of excess nitrogen by excreting it through the urine as urea, uric acid, and ammonia. But reptiles and birds take a different approach. They convert some of those nitrogen-based compounds into solids known as urates, which are expelled through a common opening called the cloaca. Scientists believe this solid form of waste evolved as an adaptation to conserve water, a valuable trait for animals that often live in dry environments.

What is dangerous to humans is normal for snakes

Although the formation of crystals in urine helps reptiles survive, the same process can cause serious health problems in humans. When uric acid levels become too high in humans, crystals can collect in the joints, leading to gout, or form in the urinary tract as kidney stones. To understand how reptiles are able to excrete these crystals safely, Jennifer Swift and her research team analyzed urates from more than 20 species.

“This research was really inspired by a desire to understand the ways in which reptiles are able to excrete this substance safely, with the hope that it might inspire new approaches to disease prevention and treatment,” explains Swift, the study’s corresponding author.

Microscopic fields with great medical potential

Using powerful microscopes, researchers have discovered that species such as ball pythons, Angolan pythons, and the Madagascar tree snake produce galls consisting of tiny balls between 1 and 10 micrometers across. X-ray analysis revealed that these microspheres are made of smaller nanocrystals made of uric acid and water. The team also found that uric acid helps convert ammonia, a toxic compound, into a safer solid form. They believe that uric acid may play a similar protective role in humans. Although more research is needed, these findings suggest that the chemistry behind reptile waste could eventually help scientists develop better treatments for uric acid-related diseases.

Support research and collaboration

This study received support from the National Science Foundation, Georgetown University, the International Diffraction Data Center, and the Chiricahua Desert Museum.