Mold Toxins Found in Foods Can Weaken Respiratory Defenses

While most people are afraid of pesticides in their food, they are usually unaware of the dangers posed by natural toxins produced by fungi (mycotoxins). Mycotoxins can be poisonous and carcinogenic. For example, the group of toxins known as aflatoxins is the second leading cause of cancer in the world.

One-quarter of the world’s food is contaminated with these types of molds. In addition, grain-based food for livestock and pets frequently contains toxin-producing molds. While eating contaminated food is highly unhealthy, another way that these toxins can enter the system is through inhaling contaminated dust during food processing.

New research from the University of Pennsylvania’s Perelman School of Medicine showed that inhaling these toxic chemicals can dramatically impair the ability of the cells in the airways to defend themselves.

The researchers looked at the effect of aflatoxins on human upper airway cells. They found that contact with these toxins inhibited the ability of the cilia to clean out dirt and dust from airway tracts.

This can enhance the pathogenicity of the fungi and possibly bacteria found in the respiratory tracts. This situation is particularly dangerous for people with compromised immune systems and could exacerbate more serious lung diseases such as COPD or cystic fibrosis. Such infections can be fatal in immunocompromised people such as those undergoing chemotherapy or poorly controlled diabetics.

Antibiotic treatment can help contain these upper respiratory diseases, but heavy antibiotic use can contribute to resistance to the drugs. Chronic sinus infections can seed lower respiratory tract infections especially in people who are immunocompromised.

About 20% of antibiotic prescriptions in the US are for chronic sinus infections. In addition to costing $8 billion a year, these prescriptions are a major driver of antibiotic resistance.

This research provided insights into potential ways to treat such fungal infections without the need for antibiotics. The scientists identified increased activity of an enzyme called protein kinase C (PKC) that inhibits the cilia. Using inhibitors to PKC may provide treatment for fungal respiratory diseases and reduce the need for antibiotics.

This study examined acute exposure of respiratory cells to aflatoxins, and longer-term studies should help to shed light on the effect of chronic exposure in the airways.