Possible link between chitin found in fungal spores and asthma

You might remember the term chitin from Biology class when discussing the exoskeletons of insects, crustaceans, and spiders.    Basically, it is a polysaccharide (sugar)  responsible for “storage materials, structural components, or protective substances.”(1)  However what you may not know is that chitin is also found in the cell walls of fungi.

The following is from Mold In Home May Be Asthma Risk by Kristina Fiore:

“Patients with certain gene variants may have an increased risk of severe asthma attacks when exposed to fungus, researchers have found…

“Our results support increasing evidence that CHIT1, which is primarily expressed in the lung, plays an important role in the pathophysiology of asthma in the proper environmental context of exposure to chitin, which was approximated by mold levels,” Wu said in a statement.

Chitinases are enzymes that metabolize chitin, a compound found in fungal cells. Two types of human chitinases — CHIT1 and acidic mammalian chitinase (CHIA) — and the chitinase-3 like 1 protein (CHI3LI) appear to play an important role in asthma.

Researchers say they perform important defensive functions against chitin-containing pathogenic organisms in both the gastrointestinal tract and lungs. CHIT1 is primarily expressed in the lung.

 And since fungal exposure has long been associated with severe asthma, the researchers decided to investigate whether exposure to environmental fungi may modulate the effect of chitinases in asthmatics.”

To read the complete article http://www.medpagetoday.com/AllergyImmunology/Asthma/20863

1. Biochemistry, by Garrett and Grisham. 1995 Sauders College Publishing