Asthma drug activates healthy fat, no cold plunges needed
Take a look at the health influencers clicking up followers on social media these days and you'll start to notice a trend involving some variation of taking cold showers, soaking in special tubs that make the water ice-cold, or diving into freezing bodies of water. While these self-styled health gurus tout the ability of cold-water bathing to do everything from reducing anxiety to helping with depression, actual scientists have discovered something it can do: convert unhealthy white fat cells into healthy brown fat. Now, researchers have figured out how to activate this process chemically with no need to brave frigid water. The discovery could lead to better treatments for diabetes and cardiovascular diseases.
While body fat gets a bad rap overall, brown fat really belongs in its own category. That's because, unlike white fat – the stuff that accumulates on our bellies and thighs, and leads to a wide range of health conditions – brown fat actually helps us lose weight. It does so by burning up sugar and fat molecules in the body to create heat, in a process known as thermogenesis. It's long been known that cold can activate brown fat, but not everyone wants to sit in a chilly bath to get the beneficial effects.
This fact has led scientists to find alternative ways to recruit brown fat cells into action. In 2020, endocrinologist Patrick Rensen and his colleagues figured out that we have a chemical target called a beta2-adrenergic receptor (b2-AR) in our bodies which can activate brown fat cells. Working with researchers at Leiden University Medical Center in the Netherlands, Rensen was able to take the lab findings and apply them to human volunteers.
He and his team gave 10 volunteers a drug called salbutamol, a b2-RA activator that is typically used to treat asthma. They then watched how brown fat behaved in the body using PET-CT scans. The team saw that after the drug was administered, it dramatically increased the amount of sugar that was consumed by the brown fat cells. When the b2-AR receptor was blocked, the effect vanished.
"With this knowledge, we can make new stimulators that activate brown fat," said Rensen, adding that the finding could help fight cardiovascular disease and type 2 diabetes because of the way in which brown fat not only gobbles glucose but cholesterol as well.
While the finding is promising, much like the study that associated another asthma drug called zafirlukast with brown fat production last year, more research is needed. In the case of zafirlukast, the quantities needed to have a beneficial effect in the body would be toxic. In this new study, beta-2 receptors were activated across the body, not just in brown fat cells.
"The first step will be to find a substance that 'turns on' this receptor only on brown fat cells," Rensen said, regarding future research. "This is because the beta-2 receptor is also found on other tissues in our body. We must first find a way to direct such stimulators very specifically to brown fat. That way, we can prevent side effects of these stimulators elsewhere in the body."
Still, along with other techniques such as using a hydrogel and light to convert white fat to brown, the current research adds another potential tool that may not only help banish beer bellies, but could also help save the lives of those struggling with serious illnesses, including cancer.
The research was published in the journal Cell Reports Medicine.
Source: Leiden University Medical Center