Psychophysical effects of nasal and oral inflammation

Smell and Taste Function and Their Disturbances in Sjögren's Syndrome

Chemosensory disorders are a possible disturbance in Sjögren's syndrome (SS). The aim of the study is to comprehensively present chemosensory disorders in SS and to indicate their possible causes. The possible causes of taste and smell disorders in SS are changes in the structure of exocrine glands and their dysfunction, damage to receptors and weakening of their ability to regenerate, and neurological changes in the form of peripheral neuropathy and impaired cognitive function. Other postulated causes of chemosensory disorders are autoimmune mechanisms, adverse effects of drugs used in SS, and primary potentially SS-triggering viral infections. They are multifactorial and may occur independently of each other. The time of their onset and correlation with other disease symptoms may facilitate the determination of their primary cause in each patient. Awareness of chemosensory disorders in SS may help to ease their progress and eliminate other factors responsible for their more severe manifestation. In the prevention and treatment of chemosensory disorders in SS, the most important thing is to alleviate xerostomia and dryness in the nasal cavity and their effects in the form of chronic local inflammations, counteract receptor atrophy, and an implementation of appropriate neurological diagnosis and treatment.

Immune responses in the injured olfactory and gustatory systems: a role in olfactory receptor neuron and taste bud regeneration?

Sensory cells that specialize in transducing olfactory and gustatory stimuli are renewed throughout life and can regenerate after injury unlike their counterparts in the mammalian retina and auditory epithelium. This uncommon capacity for regeneration offers an opportunity to understand mechanisms that promote the recovery of sensory function after taste and smell loss. Immune responses appear to influence degeneration and later regeneration of olfactory sensory neurons and taste receptor cells. Here we review surgical, chemical, and inflammatory injury models and evidence that immune responses promote or deter chemosensory cell regeneration. Macrophage and neutrophil responses to chemosensory receptor injury have been the most widely studied without consensus on their net effects on regeneration. We discuss possible technical and biological reasons for the discrepancy, such as the difference between peripheral and central structures, and suggest directions for progress in understanding immune regulation of chemosensory regeneration. Our mechanistic understanding of immune-chemosensory cell interactions must be expanded before therapies can be developed for recovering the sensation of taste and smell after head injury from traumatic nerve damage and infection. Chemosensory loss leads to decreased quality of life, depression, nutritional challenges, and exposure to environmental dangers highlighting the need for further studies in this area.

Olfaction in Chronic Rhinosinusitis

Olfactory dysfunction is a frequent complaint in chronic rhinosinusitis patients and has a significant impact on quality of life. Therefore, it is essential that clinicians are aware of the importance of olfactory dysfunction in chronic rhinosinusitis (CRS) patients and know how to deal with it. Notably, the evaluation of olfactory function (i.e., using psychophysical testing) and imagery of olfactory bulb play an important role in the evaluation of patients and give essential information about the "baseline" olfactory function. Because the high impact of olfactory function on quality of life and medical and/or surgical treatment should be proposed to patients. However, it remains difficult to predict the outcome of treatment as well as long-term efficacy. The first section of this review is dedicated to the assessment of olfactory function. Secondly, we will discuss the etiopathology of olfactory dysfunction in CRS with and without nasal polyps. Finally, we will review literature findings about the efficacy of different treatments on olfactory function.

Taste bud regeneration and the search for taste progenitor cells

While the taste periphery has been studied for over a century, we are only beginning to understand how this important sensory system is maintained throughout adult life. With the advent of molecular genetics in rodent models, and the upswing in translational approaches that impact human patients, we expect the field will make significant advances in the near future.