Distraction of olfactory bulb-medial prefrontal cortex circuit may induce anxiety-like behavior in allergic rhinitis

Abstract

Allergic rhinitis is a chronic inflammatory disease of the upper respiratory tract, which is associated with high incidence of anxiety symptom. There is evidence that medial prefrontal cortex modulates anxiety-related behaviors and receives projections from olfactory bulb. Since olfactory dysfunction has been reported in allergic rhinitis, we aimed to evaluate anxiety-like behavior and oscillations of olfactory bulb-medial prefrontal cortex circuit in an animal model of allergic rhinitis. The number of open arm entries in elevated zero maze was significantly reduced in sensitized rats exposed to intranasal ovalbumin compared to the control group, which was indicating the enhancement of anxiety-like behavior in allergic rhinitis animals. Analysis of local field potentials in olfactory bulb and medial prefrontal cortex during immobility and exploration state showed that anxiety-like behavior induced by allergic rhinitis was in association with increased activity of medial prefrontal cortex and enhancement of olfactory bulb-medial prefrontal cortex coupling in delta and theta bands. Moreover, in allergic rhinitis animals, theta strongly coordinates local gamma activity in olfactory bulb and medial prefrontal cortex, which means to have a strong local theta/gamma coupling. We suggested that disruption of olfactory bulb-medial prefrontal cortex circuit due to allergic reactions might have a governing role for inducing anxiety-like behavior in the allergic rhinitis experimental model.

Microgliosis and neuronal proteinopathy in brain persist beyond viral clearance in SARS-CoV-2 hamster model

“…Release of factors from local immune-cells or infected mucosa cells may provide a potential mechanism of communication between infected/inflamed nasal tissue and brain. 51 , 52 , 53 , 54 , 55 Similar observations of host response to combat viral entry were made for other viruses that enter via the olfactory system. 56 , 57 , 58 Therefore, it is important to compare our observations with other respiratory virus infections, such as influenza to enable identification of SARS-CoV-2 specific effects.…”

Mechanism of allergic rhinitis treated by Centipeda minima from different geographic areas

“…2013 ; Salimi et al. 2019 ). After successful establishment of the model, the rats in the blank group and model group were given normal saline in nasal cavity every day.…”

“…Thirty rats were randomly divided into 3 groups. All groups, except the blank control group, were injected with ovalbumin OVA (purchased from Sigma) and aluminum-containing adjuvant to initiate allergic rhinitis model according to the previously described method (Liu et al 2013;Salimi et al 2019). After successful establishment of the model, the rats in the blank group and model group were given normal saline in nasal cavity every day.…”

Allergic Rhinitis and Depression: Profile and Proposal

“…There have been no other animal studies on AR-related depression in recent years. However, some animal studies on abnormal brain responses secondary to nasal immune-inflammatory responses after AR have been reported, and it has been suggested that brain regions such as hippocampus, cortex, and olfactory bulb are closely related to the development of mental disorders in AR animals (35)(36)(37). Along with the achievements in animal model studies, some authors have also conducted relevant experiments using blood samples and cells from depressed patients and AR patients, and confirmed the correlation between the neurotransmitter 5-hydroxytryptamine and the cytokines secreted by T lymphocytes during an allergic reaction (38).…”