A research study by scientists at the Perelman School of Medicine found that toxins from a type of mold called aflatoxins can weaken the airways’ self-clearing mechanisms and immunity, which may lead to respiratory diseases and the exacerbation of existing ones. Aflatoxins are mycotoxins produced by fungi, known as molds, which are pathogens that can opportunistically colonize the human respiratory tract, according to Lung Disease News. For the study, researchers examined the effects of acute exposure to aflatoxins on airway cell physiology using human upper airway cells.
The research team found that acute exposure to aflatoxins decelerated and weakened key defense mechanisms in the airways, specifically the mucosal ciliary clearance (MCC) and ciliary beat frequency (CBF). MCC is the primary physical defense of the respiratory tract against inhaled pathogens, and when the MCC fails, respiratory infections can occur and notably impair the patient’s quality of life.
According to the researchers, the findings of the study show that aflatoxins boost fungi development and other co-infecting pathogens, such as bacteria, reports Lung Disease News. Lead author of the study Robert J. Lee, PhD, says “With these defenses impaired, it may create a window of opportunity for the infection, and potentially a domino effect.”
Noam A. Cohen, MD, PhD, explains that some patients “may become more susceptible to upper respiratory infections and chronic rhinosinusitis (CRS) that can ‘seed’ lower respiratory infections, especially in those with a compromised immune system. It can also exacerbate the more severe lung diseases, such as cystic fibrosis or chronic obstructive pulmonary disease.”
Researchers also found that aflatoxins activate the protein kinase C (PKC), which is involved in decreasing ciliary beat frequency and decrease MCC. According to the researchers, PKC can represent a treatment target.
The researchers tested the effects of two PKC inhibitors and found that the drugs blocked the reduction in ciliary beat frequency. As a result, PKC inhibitors may be used as a treatment for fungal infections and to prevent other co-infections, as indicated on the Lung Disease News report. Cohen says, “PKC inhibitors may decrease fungal respiratory disease and ultimately help alleviate some of those consequences.”
Additional studies of aflatoxin exposure levels are critically needed to help understand the consequences of both acute and chronic aflatoxin respiratory exposure in both human and animal models, the researchers note. Overall, the research team concluded, “Longer-term studies of the effects of aflatoxins will help to shed light on situations of chronic exposure and effects on airways.”
Source: Lung Disease News