Short-term impact of a Western diet on the physiology of the peripheral olfactory system

Current feeding behaviors contribute to the epidemic levels of obesity and diabetes observed in Europe and worldwide. Both the quantity and the quality of ingested food are incriminated. Together with other sensory modalities, olfaction is involved in the control of food intake. Olfactory cues can influence eating behaviors, yet the nutritional status and diet can also alter olfactory abilities. Patients with metabolic disorders present impaired olfactory sensitivity which could in turn worsen their eating behaviors.Here we examined the short-term impact of a Western diet enriched in fat and sugar (High Fat High Sugar, HFHS) on the anatomy and physiology of the olfactory epithelium of postn…

In vivo high-throughput identification of olfactory receptor repertoire coding for a blending mixture

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Functional analysis of broadly tuned odorant receptors expressed in the mouse septal organ through patch-clamp recordings in an intact preparation and luciferase assay in a heterologous expression system

The septal organ (SO) is a small island of olfactory epithelium located at the ventral base of the nasal septum. SO neurons express identified odorant receptors, but its function remains unknown. Using perforated patch clamp recordings, we investigated the response properties of SO neurons in the intact epithelium of mice to a panel of 45 odorants or mixtures. Out of 328 neurons tested, approximately 70% responded to odor stimulation. Among the responsive neurons, 72.5 % responded to multiple odorants. Responding neurons were tested with increasing concentrations of 3 odorants (octanoic acid, (+) camphor, amylacetate) and a mixture (fox urine). Dose-response curves show nanomolar threshold …

G-protein-coupled odorant receptors underlie mechanosensitivity in olfactory sensory neurons

G-protein-coupled odorant receptors underlie mechanosensitivity in olfactory sensory neurons. 34. annual meeting - Association for chemoreception sciences (AChemS)

G protein-coupled odorant receptors underlie mechanosensitivity in mammalian olfactory sensory neurons

Mechanosensitive cells are essential for organisms to sense the external and internal environments, and a variety of molecules have been implicated as mechanical sensors. Here we report that odorant receptors (ORs), a large family of G protein-coupled receptors, underlie the responses to both chemical and mechanical stimuli in mouse olfactory sensory neurons (OSNs). Genetic ablation of key signaling proteins in odor transduction or disruption of OR–G protein coupling eliminates mechanical responses. Curiously, OSNs expressing different OR types display significantly different responses to mechanical stimuli. Genetic swap of putatively mechanosensitive ORs abolishes or reduces mechanical res…

Short-term impact of a Western diet on the physiology of the peripheral olfactory system

Negative impact of high fructose diet on olfactory habilities

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Impact of diets unbalanced in n-3 polyunsaturated fatty acids on the mouse olfactory function

Negative impact of high fructose diet on olfactory abilities

Plasticity in the olfactory system: modulation by the odorant environment and diet

As the primary neuronal element in the olfactory system, olfactory sensory neurons (OSNs) are responsible for detecting odor molecules, transforming chemical information to electrical signals and sending these signals to the brain. Being exposed to the environment, their lifetime is limited. The olfactory epithelium has the remarkable ability to regenerate sensory neurons throughout life. There is little data showing the effects of the environment, such as odorant exposure, on the properties of OSNs. Similarly, knowledge on the modulation by the physiological state of the animal (i.e. nutritional status) is limited. The long-term goal of our group is to investigate how the OSNs function dur…

Olfactory receptors in the septal organ.

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Olfactory system in mammals: structural and functional anatomy

Olfactory system in mammals: structural and functional anatomy

Negative impact of high fructose diet on olfactory performances: behavioral and functional analysis

Negative impact of high fructose diet on olfactory performances: behavioral and functional analysis. 9. Forum of Neuroscience FENS

Psychobiological effects of perinatal exposure to odorants in mice. Part II: Behavioural alteration

Early exposure to odorants pre-, post- or transnatally is known to. result in a decreased avoidance or increased preference for these. odorants in mammals. There are also indications that olfactory sensitivity. for these odorants can be affected. We exposed C57-Bl/6. mice of Mor23-GFP and M71-GFP lines to lyral (LY) or acetophenone. (AC), respectively, either transnatally through the water of the. mother (1*10-5 M) or postnatally in air for 1 hr per day (20 ll pure). Animals were weaned on postnatal day 20 (P20), and 3 tests were. performed:. 1) A 3-min exploration test on P20 in a rectangular arena presenting. LY and AC under a wire mesh to measure the time spent in each. half of the arena…

High Fructose Diet inducing diabetes rapidly impacts olfactory epithelium and behavior in mice

AbstractType 2 Diabetes (T2D), a major public health issue reaching worldwide epidemic, has been correlated with lower olfactory abilities in humans. As olfaction represents a major component of feeding behavior, its alteration may have drastic consequences on feeding behaviors that may in turn aggravates T2D. In order to decipher the impact of T2D on the olfactory epithelium, we fed mice with a high fructose diet (HFruD) inducing early diabetic state in 4 to 8 weeks. After only 4 weeks of this diet, mice exhibited a dramatic decrease in olfactory behavioral capacities. Consistently, this decline in olfactory behavior was correlated to decreased electrophysiological responses of olfactory n…

Early impact of a diabetes inducing high-fructose diet on olfaction in mice

The influence of nutritional status on olfactory processes has been thoroughly investigated over the last few years. It is now well-established that both nutritional status and hormones implicated in food metabolism can effectively modulate the olfactory system from the single neuron to the behavior. Therefore, it seems likely that metabolic disorders such as type 2 diabetes (T2D) can induce olfactory dysfunctions. Indeed T2D patients display poor olfactory performances although the direct effects of diabetes on olfaction were not yet demonstrated. Here, we investigated the modulation of olfaction in young adult (5 weeks old) C57Bl/6 male mice caused by a high-fructose diet (HFruD), known t…

Olfactory sensory neurons plasticity induced by postnatal odorant exposure

Olfactory sensory neurons plasticity induced by postnatal odorant exposure. 16. International symposium on olfaction and taste (ISOT)

Biogenic Amines Modulate Olfactory Receptor Neurons Firing Activity in Mamestra brassicae

The modulatory effects of the biogenic amines octopamine and serotonin on pheromonal receptor neurons of Mamestra brassicae were investigated. The responses to sex pheromone components of two cells types (A and B) in single male long sensilla trichodea were monitored. Cell types A and B do not respond to the same compound. The response of type A to a pulse of the major sex pheromone component increased 5 min after octopamine injection. Responses of type B to other odorants increased after 30 min. In the absence of any pheromone stimulation the background firing activity of type A increased following octopamine injection. This background activity was used to evaluate the kinetics of octopami…

Broad tuning and high sensitivity of septal organ neurons in response to odorants

Impact of a high fat high sucrose maternal diet on the progeny's olfactory system

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Odorant response properties of septal organ neurons: broad tuning and high sensitivity

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Centrifugal projections to the main olfactory bulb revealed by trans‐synaptic retrograde tracing in mice

A wide range of evidence indicates that olfactory perception is strongly involved in food intake. However, the polysynaptic circuitry linking the brain areas involved in feeding behavior to the olfactory regions is not well known. The aim of this article was to examine such circuits. Thus, we described, using hodological tools such as transsynaptic viruses (PRV152) transported in a retrograde manner, the long-distance indirect projections (two to three synapses) onto the main olfactory bulb (MOB). The ß-subunit of the cholera toxin which is a monosynaptic retrograde tracer was used as a control to be able to differentiate between direct and indirect projections. Our tracing experiments show…

Odor-induced electrical and calcium signals from olfactory sensory neurons in situ

Electrophysiological recording and optical imaging enable the characterization of membrane and odorant response properties of olfactory sensory neurons (OSNs) in the nasal neuroepithelium. Here we describe a method to record the responses of mammalian OSNs to odorant stimulations in an ex vivo preparation of intact olfactory epithelium. The responses of individual OSNs with defined odorant receptor types can be monitored via patch-clamp recording or calcium imaging.

Post-natal unilateral naris occlusion in mice induces olfactory receptor-specific plasticity at the cellular level

Psychobiological effects of perinatal exposure to odorants in mice. Part II: Behavioural alterations

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Impact of a maternal high fat high sucrose diet on progeny's olfactory system

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CA-139: Impact précoce d'un régime gras et sucré sur la perception olfactive

Introduction L'odorat est un sens primordial pour guider les choix alimentaires. Certains patients diabetiques presentent une alteration de leurs capacites olfactives. De nombreuses interactions existent entre les hormones impliquees dans la regulation de l'homeostasie energetique et le systeme olfactif. Cependant, les consequences du diabete sur le systeme olfactif sont peu connues. Nous avons ici etudie les effets precoces d'un regime diabetogene enrichi en gras et sucre sur le systeme olfactif de souris. Materiels et Methodes Des souris mâles ont ete alimentees pendant 8 semaines avec un regime diabetogene enrichi en graisse et en sucre (HFHS). L'etat metabolique des animaux a ete caract…

Perforated Patch-clamp Recording of Mouse Olfactory Sensory Neurons in Intact Neuroepithelium: Functional Analysis of Neurons Expressing an Identified Odorant Receptor.

Analyzing the physiological responses of olfactory sensory neurons (OSN) when stimulated with specific ligands is critical to understand the basis of olfactory-driven behaviors and their modulation. These coding properties depend heavily on the initial interaction between odor molecules and the olfactory receptor (OR) expressed in the OSNs. The identity, specificity and ligand spectrum of the expressed OR are critical. The probability to find the ligand of the OR expressed in an OSN chosen randomly within the epithelium is very low. To address this challenge, this protocol uses genetically tagged mice expressing the fluorescent protein GFP under the control of the promoter of defined ORs. O…

Morphological and molecular changes in mouse olfactory epithelium following postnatal odorant exposures

Morphological and molecular changes in mouse olfactory epithelium following postnatal odorant exposures. 10. annual meeting of the french neuroscience society

Postnatal odorant exposure induces peripheral olfactory plasticity at the cellular level

Mammalian olfactory sensory neurons (OSNs) form the primary elements of the olfactory system. Inserted in the olfactory mucosa lining of the nasal cavity, they are exposed to the environment and their lifespan is brief. Several reports say that OSNs are regularly regenerated during the entire life and that odorant environment affects the olfactory epithelium. However, little is known about the impact of the odorant environment on OSNs at the cellular level and more precisely in the context of early postnatal olfactory exposure. Here we exposed MOR23-green fluorescent protein (GFP) and M71-GFP mice to lyral or acetophenone, ligands for MOR23 or M71, respectively. Daily postnatal exposure to …