New Discovery Could Change How Asthma Is Treated, Scientists Say

WEDNESDAY, Jan. 28, 2026 (HealthDay News) — Scientists may have uncovered a new cause of asthma that could change how the disease is treated.

Researchers at Case Western Reserve University in Cleveland, Ohio, say they’ve identified previously unknown molecules that may play a major role in asthma-related inflammation.

The findings suggest these chemicals, called “pseudo leukotrienes,” could be more important than the leukotrienes doctors have focused on for decades.

"We've found molecules that are alike in structure but generated through a completely different chemical pathway in the body," lead researcher Robert Salomon, a professor of research in chemistry, said in a news release. "We think the molecules we're calling 'pseudo leukotrienes,' may be the dominant players in the inflammatory cascade that causes disease."

The study, funded by the National Institutes of Health, was published in the January issue of the Journal of Allergy and Clinical Immunology.

For years, scientists thought asthma inflammation was mainly driven by leukotrienes — chemicals that white blood cells release when airways are irritated.

Many asthma drugs were designed to block their effects.

But Salomon’s team found that pseudo leukotrienes form in a different way. Instead of being made by enzymes, they are created when free radicals add oxygen to lipids, fatty or waxy compounds made by the body. 

Free radicals are highly reactive molecules that can be damaging if left uncontrolled.

"The free radical process is almost like an explosion or a fire," Salomon said. "It's just like when oxygen reacts with fuel and you get flames. It can easily get out of control."

The researchers think people with asthma may have fewer of the enzymes and antioxidants that normally help stop free radicals before they do harm.

Like a key turning an ignition to start an engine, both leukotrienes and pseudo leukotrienes trigger inflammation by activating the same receptor. The result: Tightened airways and breathing problems.

Current drugs like Singulair work by blocking that receptor.

But researchers say future treatments may target the free radical process itself.

"The real importance of this discovery is the possibility of treating these diseases with drugs that prevent the free radical process or moderate it rather than drugs that block the receptor," Salomon said.

Inflammation isn’t always bad. It helps the body heal and plays a role in normal brain function. Blocking inflammation too broadly could interfere with those benefits.

"If the molecules that are causing the problem are not the leukotrienes but these other molecules," Salomon said, "a better treatment would be to just stop the formation of these other molecules rather than gumming up the ignition."

To test their theory, the team compared urine samples from people with mild and severe asthma to samples from people without asthma.

They found pseudo leukotrienes were four to five times higher in people with asthma.

Levels also closely matched how severe the disease was, suggesting these molecules could someday help doctors track asthma or measure how well treatments are working.

Next, researchers plan to study whether pseudo leukotrienes also play a role in other respiratory conditions like RSV, bronchiolitis in infants and chronic obstructive pulmonary disease.

More information

The Cleveland Clinic has more on asthma.

SOURCE: Case Western Reserve University, news release, Jan. 27, 2026