Scientists discovered odor receptors in lungs – what is their clinical significance?

medical doctor looking at x-ray picture of lungs in hospitalResearchers from Washington University in St. Louis and the University of Iowa announced that odor receptors are presented not only in the nasal cavity but also on the surface of specific lung cells. Their data has been recently published in the Journal of Respiratory Cell and Molecular Biology.

Smell as well as taste belongs to the group of chemosensory senses. The olfactory system detects and discriminates volatile, airborne substances and transduce this chemical signals into perception. For many years the mechanism of olfaction has been considered as a scientific mystery. The molecular and cellular mechanisms for the reception of odor molecules in the nose has been described quite recent. In 2004, for the research on odorant receptors and the organization of the olfactory system, Linda Buck and Richard Axel received The Nobel Prize in Physiology or Medicine.

Meanwhile, Scientists at Washington University in St. Louis and the University of Iowa have showed that our lungs have odor receptors as well. The newly discovered class of cells expressing olfactory receptors in human airways is named pulmonary neuroendocrine cells (PNECs). Overexposure of human airway epithelial cells to volatile chemicals decreased levels of serotonin and others neuropeptides in PNEC resulting in airways constriction and cough. Unlike the receptors in nasal cavity which constitute a part of olfactory pathway, odor receptors in the lungs dose not send nerve impulses to the central nervous system. According to the researchers, the main role of the above mentioned receptors is to elicit a rapid, physiological response to the irritating or toxic inhaled volatile compounds.

According to the authors of the study, their findings explain clinical observations of odorant-induced airway reactions and might have a practical application. The scientists suspect that PNEC are responsible for the hypersensitivity to airborne irritants that characterize respiratory diseases, such chronic obstructive pulmonary disease (COPD), and asthma. Patients suffering from COPD display higher level of PNECs than healthy donors.

Together, these data suggest that the odor receptors on the surface of PNECs may be a potential therapeutic target. Pharmacological blockade of this receptors gives opportunity to create new, therapeutic options and improve the course of chronic diseases of the respiratory track. Regarding, still rising overall incidence of respiratory system disorders, investigating new, therapeutic methods in this group of patients seems to be crucial.

Written by: Justyna Markowicz, Agnieszka Szymczyk, Tomasz Roman

Source:
1. Gu X, Karp PH, Brody SL, Pierce RA, Welsh MJ, Holtzman MJ, Ben-Shahar Y. Volatile-Sensing Functions for Pulmonary Neuroendocrine Cells. Am J Respir Cell Mol Biol 2013 [Epub ahead of print]
2. Białaczewski L. Nagroda Nobla za rok 2004: odkrycie genów receptorów węchowych. Otorynolaryngologia 2005, 4(4), 163-168.
3. DeMaria S, Ngai J. The cell biology of smell. JCB 2010, vol. 191 no. 3 443-452.
4. Farbiszewski R, Kranc R. Olfactory receptors and the mechanism of odor perception. Polish Annals of Medicine 2013, Vol. 20, Issue 1, Pages 51–55.

Would you like to know more? Watch on MEDtube.net: Empty Nose Syndrome – Allograft Implantation

No Comments.

Leave a Reply

(required)

(required)

Time limit is exhausted. Please reload the CAPTCHA.