Sweet, sour, salty, bitter. We were all taught the four tastes detected by our tongues, and we’re getting to know a fifth, the recently recognized savory taste, or umami. Now researchers have found bitter taste receptors in another place: the lungs. That’s certainly unexpected, and so are the implications for potentially better asthma treatments based on the discovery.
Dr. Stephen B. Liggett and his team at the University of Maryland School of Medicine stumbled onto the bitter taste receptors when studying human lung tissue. Like tastebuds on the tongue, the receptors react to bitterness, but unlike tastebuds they do not send any signals to the brain. The researchers thought the taste receptors might have evolved as a protection against toxic plants, triggering constriction and then coughing after inhaling something bitter.
But when they exposed the receptors to bitter tastes, the lungs relaxed instead of tightening. Working with mice engineered to have a human form of asthma, they found that aerosolized bitter substances, such as quinine and saccharin (for its bitter aftertaste), opened up airways much more than the asthma medication albuterol did in similar mice.
BOTTOM LINE: Bitter taste receptors found in the lungs caused constricted airways to relax when exposed to bitter substances, responding more powerfully than they do to asthma drugs.
CAUTIONS: The research was conducted on cells in lab dishes and on mice, so the results might differ in humans. Also, the researchers say eating bitter food would not have the same effect seen in mice that inhaled droplets of bitter substances.
WHAT’S NEXT: Chemical modifications to bitter compounds could be devised and then tested as aerosols.
WHERE TO FIND IT: Nature Medicine, online Oct. 24
Hospital ratings not useful for high-risk surgeryPatients facing serious surgery may be highly motivated to check how well hospitals perform. Public reporting of hospital quality is intended both to help people choose where they get their care and to spur hospitals to improve. A new study says that a government website may not be helpful to patients looking for hospitals with good outcomes for certain high-risk procedures.
Lauren Nicholas of the University of Michigan and colleagues compared how well hospitals scored on the government’s Hospital Compare site with how well they did on six surgical procedures: abdominal aortic aneurysm repair, aortic valve repair, coronary artery bypass graft, esophageal resection, mitral valve repair, and pancreatic resection.
On the Hospital Compare site, researchers looked at how often hospitals complied with treatment guidelines. For the high-risk surgeries, researchers tracked whether patients died, had dangerous blood clots, or developed surgical site infections.
Compliance rates ranged from 54 percent to 91 percent, but there was no consistent relationship between compliance rates for Hospital Compare measures and surviving high-risk surgeries without complications. The authors recommend that other measures of safety and quality be used for high-risk surgery.
BOTTOM LINE: Currently available information on the government’s Hospital Compare website does not shed light on which hospitals have better outcomes for high-risk surgery.
CAUTIONS: Relatively few of the high-risk procedures were done at low-compliance hospitals.
WHERE TO FIND IT: Archives of Surgery, October