Study on in vitro differentiation of human adenoid-derived mesenchymal stem cells into olfactory sensory neurons / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate the feasibility of isolation and culture of human adenoid-derived mesenchymal stem cells (aMSCs) in vitro, and to observe the differentiation of aMSCs into olfactory sensory neurons. Methods: Adenoid tissues surgically removed from children with adenoid hypertrophy in the Second Xiangya Hospital of Central South University from September to November of 2020 were collected. The adenoid tissues were digested and isolated by trypsin and then cultured with adhesion method. The expressions of cell surface antigens CD45, CD73 and CD90 on aMSCs of P5 generation were tested by flow cytometry, and the ability of osteogenic and adipogenic induction were used to identify cell differentiation ability. Then, aMSCs were induced into differentiation by retinoic acid (RA), sonic hedgehog (SHH), basic fibroblast growth factor (bFGF), RA+SHH, RA+bFGF, SHH+bFGF and RA+SHH+bFGF, respectively. The morphology of differentiated cells was observed under inverted microscope. The expression of β-tubulin 3, which was the specific marker of sensory neuron, the expressions of growth associated protein-43 (GAP43) and olfactory maker protein (OMP), which were the specific markers of olfactory sensory neuron, were detected by immunofluorescence antibody assay. The expression intensities were compared by Chi-square test of four-grid table data. Results: aMSCs were successively isolated and cultured from human adenoid tissues. P0 cells generation had good adhesion and proliferation performance. P2 cells were basically purified. P5 cells expressed CD73 and CD90 with the purity of 99.3% and 99.75% respectively, without CD45 expression. P5 cells had a good ability of osteogenic differentiation and adipogenic differentiation. Neuron-like morphology and expression of β-tubulin 3 were found in differentiated cells after induced by RA, SHH, or bFGF, respectively. An induction of expression of GAP43 was found in differentiated cells of bFGF+SHH group and RA+SHH+bFGF group, without expression of OMP of each group. The intensity of GAP43 expression of RA+SHH+bFGF group was stronger than that of bFGF+SHH group (χ2=17.48, P<0.005). Conclusions: aMSCs can be cultured from human adenoid tissues, with the stably passaged and good differentiation ability. As a new population of mesenchymal stem cells, aMSCs have the neuroregenerative properties and could differentiate into immature olfactory sensory neurons under the induction of RA+SHH+bFGF in vitro.

Alteração na representação de subpopulações de neurônios no epitélio olfatório de camundongos Ric8b cKO / Altered representation of neuronal sub-populations in the olfactory epithelium of Ric8b conditional knock-out mice

O objetivo desse trabalho foi identificar as consequências moleculares e funcionais da falta da proteína Ric8b no epitélio olfatório de camundongos. Para esse fim, comparamos o transcriptoma de epitélio olfatório de camundongos knock-out tecido específico para a proteína RIC8B (Ric8b cKO) com o dos seus irmãos tipo selvagem (WT). Identificamos muitos genes que apresentaram expressão reduzida no epitélio olfatório do camundongo Ric8b cKO, mas também vários genes que apresentaram a sua expressão aumentada. A maioria dos genes com expressão reduzida corresponde a genes normalmente expressos em neurônios olfatórios maduros, como por exemplo os genes de receptores olfatórios, o que é compatível com o fato já conhecido de que os camundongos Ric8b cKO apresentam um menor número desses neurônios. Inesperadamente, apesar de a maioria dos genes de receptores olfatórios ter a sua expressão diminuída no camundongo Ric8b cKO, observamos que um grupo destes genes de receptores teve a sua expressão aumentada. Os camundongos Ric8b cKO apresentaram também genes marcadores de outros tipos celulares que não neurônios canônicos com expressão aumentada no seu epitélio olfatório. Dentre eles, os mais significativamente alterados foram os genes marcadores de neurônios Trpc2+ tipo B (que expressam a guanilato ciclase solúvel Gucy1b2). Sabe-se que este tipo de neurônio é responsável pela sensibilidade a diferentes gases, e concordantemente, observamos que os camundongos Ric8b cKO apresentaram um aumento da sensibilidade a gás carbônico. Como o olfato apresenta um papel importante na regulação de ingestão alimentar, analisamos como os camundongos Ric8b cKO se comportam frente a diferentes dietas. Interessantemente, observamos que esses animais não apresentam preferência por alimento rico em gorduras quando comparado aos seus irmãos tipo selvagem. Nossos resultados sugerem, portanto, que a ausência da proteína RIC8B resulta na alteração de representatividade de neurônios canônicos e não canônicos no epitélio olfatório de camundongos, o que por sua vez leva a alterações funcionais e comportamentais

The objective of this work was to identify the molecular and functional consequences of the lack of the RIC8B protein in the main olfactory epithelium of mice. To this end, we compared the olfactory epithelium transcriptome of Ric8b tissue-specific knock-out mice (Ric8b cKO) with that of their wild-type littermates (WT). We identified many genes with differential expression, many of which were downregulated and also some which were upregulated in the olfactory epithelium of the Ric8b cKO mice. Most of the downregulated genes correspond to genes normally expressed in mature olfactory sensory neurons, such as olfactory receptor genes. This is compatible with the already known fact that the Ric8b cKO mice have less of this kind of neuron. Unexpectedly, even though most of the olfactory receptor genes were downregulated, we observed a subset of these genes that had their expression upregulated in the Ric8b cKO mice. The Ric8b cKO mice also showed upregulation for genes that are markers for cell types other than canonic neurons in their olfactory epithelium. Among these, the most significantly altered were the markers for neurons Trpc2+ type B (that express the soluble guanylate cyclase Gucy1b2). It is known that this kind of neuron is responsible for sensitivity to different gases. Accordingly, we observed that the Ric8b cKO mice presented a higher sensitivity to carbon dioxide. Since olfaction has an important role in food intake, we analyzed how the Ric8b cKO mice behaved with different diets. Interestingly, we observed that the Ric8b cKO mice lack preference for high fat diet when compared to their wild-type littermates. Our results indicate, therefore, that the lack of the RIC8B protein results in altered representativity of canonic and non-canonic neurons in the olfactory epithelium of mice, which then leads to altered function and behavior

Spheroid Culture of Mammalian Olfactory Receptor Neurons: Potential Applications for a Bioelectronic Nose

The olfactory system can detect many odorants with high sensitivity and selectivity based on the expression of nearly a thousand types of olfactory receptors (ORs) in olfactory receptor neurons (ORNs). These ORs have a dynamic odorant detection range and contribute to signal encoding processes in the olfactory bulb (OB). To harness the capabilities of the olfactory system and develop a biomimetic sensor, stable culture and maintenance of ORNs are required. However, in vitro monolayer culture models have several key limitations: i) short available period of cultured neurons, ii) low cultural efficiency, and iii) long-term storage challenges. This study aims to develop a technique: i) to support the spheroid culture of primary ORN precursors facilitating stable maintenance and long-term storage, and ii) to demonstrate the viability of ORN spheroid culture in developing an olfactory system mimetic bioelectronic nose. Recombinant protein (REP; TGPG[VGRGD(VGVPG)₆]₂₀WPC) was used to form the ORN spheroids. Spheroid formation enabled preservation of primary cultured ORNs without a significant decrease in viability or the expression of stemness markers for ten days. Physiological characteristics of the ORNs were verified by monitoring intracellular calcium concentration upon odorant mixture stimulation; response upon odorant stimulation were observed at least for ten days in these cultivated ORNs differentiated from spheroids. Coupling ORNs with multi electrode array (MEA) enabled the detection and discrimination of odorants by analyzing the electrical signal patterns generated following odorant stimulation. Taken together, the ORN spheroid culture process is a promising technique for the development of a bioelectronic nose and high-throughput odorant screening device.

Editor's Introduction to This Issue (G&I 16:1, 2018)

No abstract available.

The Hitchhiker’s guide to the rhinencephalon / Um guia prático sobre a anatomia do rinencéfalo

ABSTRACT Pathology of the rhinencephalon has been a subject of interest in the fields of neurodegenerative diseases, trauma, epilepsy and other neurological conditions. Most of what is known about the human rhinencephalon comes from comparative anatomy studies in other mammals and histological studies in primates. Functional imaging studies can provide new and important insight into the function of the rhinencephalon in humans but have limited spatial resolution, limiting its contribution to the study of the anatomy of the human rhinencephalon. In this study we aim to provide a brief and objective review of the anatomy of this important and often overlooked area of the nervous system.

RESUMO As patologias do rinencéfalo tem sido assunto de interesse para os estudiosos das doenças neurodegenerativas, do traumatismo cranio-encefálico, epilepsia e outras doenças neurológicas. A maior parte do conhecimento sobre a anatomia do rinencéfalo vem de estudos de anatomia comparativa com outros mamíferos e estudos histológicos em primatas. Estudos de imagem funcional, apesar de proporcionarem informações úteis e interessantes a respeito do funcionamento do rinencéfalo em humanos, sofrem de resolução espacial limitada, e portanto contribuem de maneira restrita ao estudo dos limites das áreas anatômicas. Neste artigo buscamos proporcionar ao neurologista e neurocientista interessado uma revisão prática e objetiva da anatomia desta área importante e muitas vezes esquecida do sistema nervoso.

Yeast CUP1 protects HeLa cells against copper-induced stress

As an essential trace element, copper can be toxic in mammalian cells when present in excess. Metallothioneins (MTs) are small, cysteine-rich proteins that avidly bind copper and thus play an important role in detoxification. Yeast CUP1 is a member of the MT gene family. The aim of this study was to determine whether yeast CUP1 could bind copper effectively and protect cells against copper stress. In this study, CUP1 expression was determined by quantitative real-time PCR, and copper content was detected by inductively coupled plasma mass spectrometry. Production of intracellular reactive oxygen species (ROS) was evaluated using the 2',7'-dichlorofluorescein-diacetate (DCFH-DA) assay. Cellular viability was detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the cell cycle distribution of CUP1 was analyzed by fluorescence-activated cell sorting. The data indicated that overexpression of yeast CUP1 in HeLa cells played a protective role against copper-induced stress, leading to increased cellular viability (P<0.05) and decreased ROS production (P<0.05). It was also observed that overexpression of yeast CUP1 reduced the percentage of G1 cells and increased the percentage of S cells, which suggested that it contributed to cell viability. We found that overexpression of yeast CUP1 protected HeLa cells against copper stress. These results offer useful data to elucidate the mechanism of the MT gene on copper metabolism in mammalian cells.

Understanding the Human Sensory Conduction of Smell / 한양의대학술지

The olfactory epithelium is the main end organ for the sense of smell in humans and vertebrates. Specially differenciated neuronal cells called olfactory receptor neurons (ORNs) play a key role in the olfactory epithelium by expressing the olfactory receptors (ORs) on their apical surface membrane. The ORs are G-protein coupled receptors that transmit signals from odorants to ORNs by molecular cascades using cyclic adenosine monophosphate, calcium ions and other molecules, which result in the depolarization of ORN. Unlike other mammalian animals, only about 30% of OR genes in the human genome are expressed. The Nobel Prize was awarded to the scientists who cloned these ORs for the first time. Each ORN expresses only a single type of OR, and ORNs which express the same type of OR converge together into the same glomeruli in the olfactory bulb. A single OR recognizes multiple odorants, and a single odorant is recognized by multiple ORs with varying affinities. At the higher neurons beyond the bulb, neuronal connections are divergent. The combinatorial model of odor identification and discrimination is well established at the convergence level, but little is known about the action mechanisms of neuronal divergence for odor identification and discrimination and further study is required.

Interplay of Signaling Molecules in Olfactory Sensory Neuron toward Signal Amplification / 한양의대학술지

Over the last decades, piles of data have been accumulated to understand the olfactory sensation in every aspect, ranging from the intracellular signaling to cognitive perception. This review focuses on the ion conduction through multiple ion channels expressed in olfactory sensory neurons (OSNs) to describe how odorant binding to olfactory receptors is transduced into an electrical signal. Olfactory signal transduction and the generation of the depolarizing receptor current occur in the cilia, where the unique extraciliary environment of the nasal mucosa assists in the neuronal activation. Upon contacting with odorants, OSNs dissociate G protein-coupled receptors, initiating a signal transduction pathway that leads to firing of action potential. This signaling pathway has a unique, two step organization: a cAMP-gated Ca2+ (CNG) channel and a Ca2+-activated Cl- channel (CACC), both of which contribute to signal amplification. This transduction mechanism requires an outward-directed driving force of Cl- established by active accumulation of Cl- within the lumen of the sensory cilia. To permit Cl- accumulation, OSNs avoid the expression of the 'Chloride Sensor: WNK3', that functions as the main Cl- exclusion co-transporter in neurons of the central nervous system (CNS). Cl- accumulation provides OSNs with the driving force for the depolarization, increasing the excitatory response magnitude. This is an interesting adaptation because of the fact that the olfactory cilia reside in the mucus, outside the body, where the concentrations of ions are not as well regulated as they are in normal interstitial compartments.

Preputial gland activates olfactory receptor neurons in rat: Calcium imaging study using laser scanning confocal microscopy.

The rodent preputial gland is one of the major sources of odours and is reported to be involved in several behavioural activities. However, how the preputial gland initiates the olfactory response to manifest the effects is not known. Olfactory receptor neurons (ORNs) present in the olfactory epithelium are involved in the perception of odorant/pheromonal compounds. In the present study, the response of rat ORNs to preputial gland extract was evaluated by calcium imaging analysis. We found that some rat ORNs responded to the preputial gland extract by exhibiting an intracellular calcium response. By contrast, the ORNs did not respond at all to the foot pad extract (control). The results indicated that the substances contained in the preputial gland might interact with a type of receptor expressed in the female rat ORNs, suggested to manifest the behavioural responses, such as social and sexual interactions. This study provided the first evidence of activation of ORNs by the preputial gland extract.

RIC-8B, um fator trocador de nucleotídeo guanina (GEF), é essencial para a embriogênese / RIC-8B, a guanine nucleotide exchange factor (GEF), is essential for embryogenesisPalavras-chave em inglês Cilia

RIC-8B é uma proteína que apresenta, in vitro, atividade de fator de troca de nucleotídeos guanina (GEF). No entanto, seu papel in vivo não é conhecido. Dados anteriores do nosso laboratório demonstraram que essa proteína interage especificamente com Gαolf, que é uma proteína G exclusiva do sistema olfatório, presente nos cílios dos neurônios olfatórios, onde ocorre a transdução de sinal ativada pelos odorantes. No camundongo adulto verificou-se, por meio de ensaios de hibridização in situ, que RIC-8B está presente somente em regiões de expressão de Gαolf: no epitélio olfatório maduro e no núcleo estriado do sistema nervoso central. Para avaliar a função fisiológica de RIC-8B in vivo, resolvemos gerar uma linhagem de camundongo knockout para Ric-8B. Verificamos que a linhagem é inviável devido à letalidade dos embriões já em fases precoces do desenvolvimento (por volta de E8,5 e E9,0). A coloração de embriões com X-gal mostra que RIC-8B é especificamente expressa em regiões que darão origem ao sistema nervoso, como na região ventral do tubo neural, e em regiões cefálicas. Interessantemente, mostramos que RIC-8B é expressa na placa do assoalho do tubo neural, de uma maneira muito semelhante ao padrão de expressão de Sonic Hedgehog (SHH), que apresenta um papel fundamental para a organização do sistema nervoso, entre outras funções. Nossos resultados indicam, portanto, que RIC-8B desempenha um papel crucial durante a embriogênese, e que este papel pode estar relacionado com o papel exercido por SHH. Além disso, como a via de sinalização de SHH ocorre em cílios primários nas células alvo, nossos dados levantam a interessante possibilidade de que RIC-8B apresenta funções relacionadas a cílios, tanto no camundongo adulto (neste caso nos cílios dos neurônios olfatórios) como no embrião (neste caso nos cílios primários)

RIC-8B is a protein that, in vitro, acts as a guanine nucleotide exchange factor (GEF). However, its role in vivo remains unknown. Previous data from our laboratory demonstrated that this protein is able to interact specifically with Gαolf, a G protein found only in the olfactory system. This G protein is located in the cilia from olfactory neurons, where odorant signaling occurs. In situ hybridization experiments showed that RIC-8B, in adult mice, is expressed only in regions where Gαolf is expressed, such as the olfactory epithelium and the nucleus striatum in the central nervous system. In order to determine the function of RIC-8B in vivo, we decided to generate a knockout mouse strain for Ric-8B. We found that this strain is not viable due to the lethality of embryos in the early stages of development (around days E8.5 and E9.0). X-gal staining of embryos shows that RIC-8B is specifically expressed in regions that originate the nervous system, such as the ventral neural tube and also cephalic regions. Interestingly, we show that RIC-8B is restrictedly expressed in the floor plate of the neural tube, in a pattern that is very similar to the one shown by Sonic Hedgehog (SHH). The SHH protein plays a fundamental role in the organization of the nervous system, among other functions. Therefore, our results indicate that RIC-8B plays an essential role during the embryogenesis, and that this role can be related to the role played by SHH. Furthermore, because the SHH signaling pathway occurs in primary cilia in the target cells, our data raise the interesting possibility that the role played by RIC-8B is related to ciliary functions, both in adult mice (in this case, in olfactory cilia), and in the embryo (in this case, in primary cilia)

Research progress of external tufted cells in olfactory glomerulus / 生物医学工程学杂志

External tufted (ET) cells are the major excitatory elements coordinating the activities of glomerulars and mediating the input from the olfactory neurons to mitral cells. The ET cells participate in inter-and intra-glomerular microcircuits in the olfactory bulb, link the isofunctional odor columns within the same olfactory bulb, and play an important role in olfactory information processing. This paper reviews the research progress of the anatomy and physiological properties and electrophysiological modeling of ET cells, elaborate the problems and defects in the field. And then it further gives some proposals for the future research of electrophysiological properties, development of olfactory information coding and performance of modeling of ET cells.

Research progress on olfactory receptor / 浙江大学学报·医学版

The olfactory perception is the process that the olfactory receptor is activated by odorous molecules, which induce the transduction of signal in the cell and the chemical information is transduced into electrical impulses. After the changed signal is transmitted to the brain, the whole perception process completes. OR gene belongs to the multigene family. The coded olfactory receptor proteins belong to the G-protein-coupled receptor (GPCR) superfamily and therefore are invariably seven-transmembrane domain(7TM) protein. Olfactory receptor protein plays an important role in olfactory perception and signal transduction process.

Microstructural changes of olfactory mucosa in rat model with acute rhinosinusitis leading to olfactory dysfunction / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To observe the microstructural changes of olfactory mucosa in rat model with acute rhinosinusitis leading to olfactory dysfunction, and to provide foundation for further exploration of corresponding mechanism.</p><p><b>METHODS</b>On the basis of prior successfully established rat model of acute rhinosinusitis through inoculation with Streptococcus pneumoniae and with the help of merocel strips, one hundred healthy SD rats were randomly divided into experimental group (80) and control group (20). After inoculation, every 20 rats in the experimental groups were sacrificed in first week, second week, third week and fourth week respectively; and all rats in the control group were sacrificed in first week after the inoculation. Before the rats were sacrificed, the method called "buffed food pellet test, BFPT" was adopted, which was advanced by professor Nathan, to measure the rats' olfaction,and the time of every rat spending in finding out the food pellet was recorded and analyzed. BFPT showed that the rats in experimental group spent (402.9 ± 9.3), (453.7 ± 7.3), (351.9 ± 8.9), (278.7 ± 8.1) s respectively in searching the food pellet, which were more than the rats in the control group [(178.3 ± 6.6) s]. Then the olfactory mucosa was collected under anatomic microscope from all the rats to make frozen section and detect the changes of mature olfactory receptor neurons (ORN) and olfactory ensheathing cells (OEC) by immunofluorescence technique.</p><p><b>RESULTS</b>The reduction of ORN in various degrees could be detected in the tissue samples of olfactory mucosa among all the rats in experimental group, with a tendency to become thinner in the thickness of epithelial lamina during the inflammation developing course. This kind of pathology was most marked in the second week and it gradually developed into the stage showing the lesion being the feeblest in the forth week following the beginning of modeling. Although the number of olfactory ensheathing cells appeared reduction in the first week following the beginning of modeling as well,it came to increase from the second week before olfactory receptor neurons and almost completely recovered to normal in the fourth week. In addition, some olfactory ensheathing cells could be detected in the tissue samples of olfactory mucosa among all the rats in experimental group.</p><p><b>CONCLUSIONS</b>Both mature olfactory sensory neurons and olfactory ensheathing cells appeared to reduction when sinonasal mucosa taken place acute rhinosinusitis. But the number of olfactory ensheathing cells increased faster than olfactory sensory neurons. In addition, some olfactory ensheathing cells could be detected in the olfactory epithelium.</p>

Research progress of olfactory receptor neurons and its application in olfactory biosensors / 生物医学工程学杂志

Olfactory organ is an important sensory system and therefore it can serve as the research object of the neural information processing and biologic evolution due to its simplicity and ancient characteristics of the system. Besides, the olfactory biosensors based on olfactory receptor neurons (ORNs) have prosperous applications in environmental monitoring and food testing. This review introduces configuration and signal transduction of ORNs. Then it examines neuronal coding strategies and how the characteristic of responses to mechanical stimuli applied to olfactory processing. Finally, it illustrates the recent research of olfactory biosensors based on ORNs/olfactory receptors and puts forward the direction of future research.

The role of intracellular Ca2+ release in olfactory signal transduction / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To setup the real time monitor system of the concentration of free intracellular calcium ([Ca2+]i) of olfactory receptor neurons (ORNs) cultured from olfactory epithelium explant, and to analyze the role of several important components in olfactory signal transduction.@*METHOD@#The [Ca2+]i of the cultured ORNs was determined by fluorescence microscopy using the fluorescent calcium indicator, Fura-2 AM, and calculated by means of dual-wavelength ratiometric method. Forskolin and IBMX were used to stimulate the cultured ORNs respectively. The source of corresponding [Ca2+]i elevation was studied by the depletion of extracellular or intracellular calcium.@*RESULT@#The [Ca2+]i of silent ORNs was (58.5 +/- 12.8) nmol/L. Forskolin or IBMX stimulation led to reversible accumulation of [Ca2+]i in the ORNs. The [Ca2+]i change was abolished with the removal of extracellular Ca2+ and un-affected by treatment with thapsigargin.@*CONCLUSION@#A system to visualize and quantify [Ca2+]i of the ORNs was established. [Ca2+]i of the ORNs was regulated by second messenger gated calcium channels.

Expression of odorant receptor genes on the olfactory epithelium following olfactory nerve disconnection / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To constitute the animal model of unilateral olfactory nerve transection and observe the expression level and distribution of odorant receptors.</p><p><b>METHODS</b>Thirty-two rats were divided into two groups: the olfactory nerve transection group (20) and the control group (12). The former group received the operation to transect the left olfactory nerve following the left olfactory bulb was exposed under microscope and the latter group did not give any disposal. At every stage of five days, two weeks, four weeks and six weeks after the operation, five rats from the nerve transection group and three from the control group were anaesthetized simultaneously, and olfactory epithelium were taken out after transcardial perfusion, then paraffin imbedding. Coronal sections were sliced for HE staining to observe the thickness changes of the olfactory epithelium, and for in situ hybridization (ISHs) to investigate the expression of olfactory receptor genes (Olr287, Olr226, Olr1493 and Olr1654) in the epithelium, also to evaluate the changes of the expression level and location of the selected receptors during the regeneration of olfactory epithelium.</p><p><b>RESULTS</b>HE staining showed that 5 days after the operation cell quantity and thickness of the olfactory epithelium decreased obviously, which increased gradually 2 or 4 weeks after operation. After 6 weeks' recovery, the thickness of the epithelium could reach the control level. The pattern of cell staining by ISH showed a specific spatial distribution along the anteroposterior (AP) and dorsoventral (DV) axis. Evidence suggested that odorant receptors were distributed in continuous and multiple overlapping bands in the normal or nerve transected-recovered epithelium rather than in the conventionally accepted three or four zones. The data also demonstrated that the distribution of sensory neuron types, as identified and defined by odorant receptor expression, was restored to normal or nearly so by 6 weeks after operation. Likewise, the numbers of probe-labeled neurons in the nerve transected-recovered had an obvious decrease 5 days after olfactory nerve transection. Reactive cells (x(-) +/- s) of Olr1493 in the operated side was (53.9 +/- 19.9), compared with (419.0 +/- 21.2) in the unoperated side, there was statistic significance between them (t = 63.960, P < 0.01). Reactive cells increased gradually according to the regeneration of the epithelium, and were nearly equivalent to the normal side 6 weeks later without significant differentiation (t = 2.600, P > 0.05), according to the absolute positive cells in the operated and unoperated side of (417.8 +/- 32.4) and (445.3 +/- 10.0) respectively.</p><p><b>CONCLUSION</b>The regeneration of the sensory neurons and receptors, both the number and the distribution, can recover to normal after olfactory nerve transection.</p>

RIC-8B, uma GEF putativa do sistema olfatório, interage com G´ALFA´olf, G´BETA´1, e G´GAMA´13 / RIC-8B, a putative GEF of the olfactory system, interacts with G´ALFA´olf, G´BETA´1, e G´GAMA´13

O sistema olfatório de mamíferos é capaz de detectar milhares de substâncias químicas diferentes, mesmo em baixas concentrações. Um odorante disperso no ar pode se ligar a um receptor olfatório (OR) iniciando o processo de detecção. Os ORs são membros da super família de receptores acoplados a proteína G (GPCRs). Apesar de a via de transdução de sinal de odorantes estar bem descrita, pouco se sabe sobre os seus moduladores. Em 2005, nosso laboratório identificou RIC-8B como um possível fator de troca de nucleotídeos de guanina (GEF) que poderia amplificar a atividade da proteína G olfatória (Golf). No presente trabalho mostramos que RIC-8B é capaz de interagir com Gγ13. Procurando os outros componentes desse complexo identificamos Gβ1 como sendo a subunidade Gβ mais expressa no epitélio olfatório...

Análise das regiões promotoras dos genes de receptores olfatórios e de receptores de feromônios do tipo 1 / Analysis of promoter regions of the olfactory and type 1 vomeronasal receptor genes

No genoma de camundongo existem por volta de 1000 genes que codificam para receptores olfatórios (ORs) e 150 genes que codificam para receptores de feromônios do tipo 1 (V1Rs) distribuídos em vários cromossomos. Cada neurônio olfatório e vomeronasal seleciona um único alelo de um único gene de receptor OR ou de V1R, respectivamente, para expressar enquanto que o restante do repertório é mantido silenciado. Os mecanismos que regulam esse padrão de expressão não são conhecidos. As similaridades no padrão de expressão dos genes de ORs e de V1Rs sugerem que o mecanismo de regulação possa ser comum. Até então poucas regiões promotoras de genes de ORs e de genes de V1Rs haviam sido experimentalmente determinadas e pesquisadas. Realizamos uma análise na qual regiões a montante de um grande número de diferentes genes de ORs e de genes de V1Rs foram comparadas...

Biología feromonal en la especie humana / Pheromone biology and human behaviour

Las funciones de quimiosensitividad y quimiosensorialidad de la nariz humana han sido siempre despreciadas, pero el incremento de evidencias a partir de investigaciones en otras especies animales sugiere que la olfación puede servir para otros propósitos muy importantes. En mamíferos está mediada por distintos órganos localizados en la cavidad nasal, como el epitelio olfatorio que une moléculas volátiles, responsable de la percepción consciente de olores y el órgano vomeronasal (OVN) que une feromonas y origina varias respuestas sobre todo entre individuos de una misma especie. Moléculas olorosas y feromonas se unen a receptores que permiten la señal de transducción, que son codificados por grandes familias multigénicas. Esta revisión presenta la información reciente y actualizada acerca de la temática de feromonas humanas.

Research progress of the olfactory neural system recognition model / 生物医学工程学杂志

Compared with other sensory system, olfactory neural system may be the most unknown one. And it is reported that the research of the complicated olfactory system is beneficial to clarifying the whole mechanism of the sensory system. Focused on spatiotemporal coding and decoding mechanism, the studies on the olfactory neural system recognition models are especially introduced. Finally, this paper presents the research work carried out in our lab, and prospects the development of this field in the future.