7 results on '"Franceschini, Valeria"'
Search Results
2. Immunocytochemical characterization of olfactory ensheathing cells in fish
- Author
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Lazzari, Maurizio, Bettini, Simone, and Franceschini, Valeria
- Published
- 2013
- Full Text
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3. Immunocytochemical characterisation of olfactory ensheathing cells of zebrafish.
- Author
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Lazzari, Maurizio, Bettini, Simone, and Franceschini, Valeria
- Subjects
IMMUNOCYTOCHEMISTRY ,OLFACTORY receptors ,DEVELOPMENTAL neurobiology ,REGENERATION (Biology) ,LABORATORY zebrafish ,NEUROGLIA - Abstract
Continuous lifelong neurogenesis is typical of the vertebrate olfactory system. The regenerative ability of olfactory receptor neurons is dependent on the glial cell type specific to the olfactory pathway, designated 'olfactory ensheathing cells'. Several studies to date have focused on mammalian olfactory ensheathing cells, owing to their potential roles in cell-based therapy for spinal cord injury repair. However, limited information is available regarding this glial cell type in non-mammalian vertebrates, particularly anamniotes. In the current immunocytochemical study, we analysed the features of olfactory ensheathing cells in the zebrafish, Danio rerio. Fish provide a good model for studying glial cells associated with the olfactory pathway of non-mammalian vertebrates. In particular, zebrafish has numerous valuable features that enable its use as a prime model organism for genetic, neurobiological and developmental studies, as well as toxicology and genomics research. Paraffin sections from decalcified heads of zebrafish were processed immunocytochemically to detect proteins used in the research on mammalian olfactory ensheathing cells, including glial fibrillary acid protein ( GFAP), S100, neural cell adhesion molecule ( NCAM), polysialylated NCAM ( PSA- NCAM), vimentin (VIM), p75 NTR and galactin (Gal)-1. Notably, GFAP, S100, NCAM and Gal-1 were clearly observed, whereas no vimentin staining was detected. Weak immunostaining for PSA- NCAM and p75 NTR was evident. Moreover the degree of marker expression was not uniform in various tracts of the zebrafish olfactory pathway. The immunostaining patterns of the zebrafish olfactory system are distinct from those of other fish to some extent, suggesting interspecific differences. We also showed that the olfactory pathway of zebrafish expresses markers of mammalian olfactory ensheathing cells. The olfactory systems of vertebrates have similarities but there are also marked variations between them. The issue of whether regional and interspecific differences in immunostaining patterns of olfactory pathway markers have functional significance requires further investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
4. Differential nickel-induced responses of olfactory sensory neuron populations in zebrafish
- Author
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Valeria Franceschini, Maria Gabriella Maurizii, Simone Bettini, Liliana Milani, Maurizio Lazzari, Lazzari, Maurizio, Bettini, Simone, Milani, Liliana, Maurizii, Maria Gabriella, and Franceschini, Valeria
- Subjects
Olfactory system ,Nickel ion ,Crypt cell ,Health, Toxicology and Mutagenesis ,Crypt ,Sensory system ,010501 environmental sciences ,Aquatic Science ,Biology ,01 natural sciences ,Olfactory Receptor Neurons ,Olfactory sensory neuron ,Rosette (botany) ,03 medical and health sciences ,Olfactory Mucosa ,Nickel ,medicine ,Animals ,Zebrafish ,030304 developmental biology ,0105 earth and related environmental sciences ,0303 health sciences ,Olfactory epithelium ,biology.organism_classification ,Immunohistochemistry ,GTP-Binding Protein alpha Subunits ,Sensory neuron ,Cell biology ,medicine.anatomical_structure ,Water Pollutants, Chemical ,Immunostaining - Abstract
The olfactory epithelium of fish includes three main types of olfactory sensory neurons (OSNs). Whereas ciliated (cOSNs) and microvillous olfactory sensory neurons (mOSNs) are common to all vertebrates, a third, smaller group, the crypt cells, is exclusive for fish. Dissolved pollutants reach OSNs, thus resulting in impairment of the olfactory function with possible neurobehavioral damages, and nickel represents a diffuse olfactory toxicant. We studied the effects of three sublethal Ni2+ concentrations on the different OSN populations of zebrafish that is a widely used biological model. We applied image analysis with cell count and quantification of histochemically-detected markers of the different types of OSNs. The present study shows clear evidence of a differential responses of OSN populations to treatments. Densitometric values for Gα olf, a marker of cOSNs, decreased compared to control and showed a concentration-dependent effect in the ventral half of the olfactory rosette. The densitometric analysis of TRPC2, a marker of mOSNs, revealed a statistically significant reduction compared to control, smaller than the decrease for Gα olf and without concentration-dependent effects. After exposure, olfactory epithelium stained with anti-calretinin, a marker of c- and mOSNs, revealed a decrease in thickness while the sensory area appeared unchanged. The thickness reduction together with increased densitometric values for HuC/D, a marker of mature and immature neurons, suggests that the decrements in Gα olf and TRPC2 immunostaining may depend on cell death. However, reductions in the number of apical processes and of antigen expression could be a further explanation. We hypothesize that cOSNs are more sensitive than mOSNs to Ni2+ exposure. Difference between subpopulations of OSNs or differences in water flux throughout the olfactory cavity could account for the greater susceptibility of the OSNs located in the ventral half of the olfactory rosette. Cell count of anti-TrkA immunopositive cells reveals that Ni2+ exposure does not affect crypt cells. The results of this immunohistochemical study are not in line with those obtained by electro-olfactogram.
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- 2019
5. Differential response of olfactory sensory neuron populations to copper ion exposure in zebrafish
- Author
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Valeria Franceschini, Liliana Milani, Maria Gabriella Maurizii, Simone Bettini, Maurizio Lazzari, Lazzari, Maurizio, Bettini, Simone, Milani, Liliana, Maurizii, Maria Gabriella, and Franceschini, Valeria
- Subjects
Olfactory system ,Crypt cell ,Health, Toxicology and Mutagenesis ,Sensory system ,Olfaction ,010501 environmental sciences ,Aquatic Science ,Biology ,01 natural sciences ,Olfactory Receptor Neurons ,Olfactory sensory neuron ,03 medical and health sciences ,Olfactory mucosa ,0302 clinical medicine ,Olfactory Mucosa ,medicine ,Animals ,Zebrafish ,0105 earth and related environmental sciences ,Copper ion ,Olfactory epithelium ,biology.organism_classification ,Immunohistochemistry ,Sensory neuron ,Cell biology ,medicine.anatomical_structure ,Immunology ,Copper ,Water Pollutants, Chemical ,030217 neurology & neurosurgery ,Immunostaining ,Olfactory recovery - Abstract
The peripheral olfactory system of fish is in direct contact with the external aqueous environment, so dissolved contaminants can easily impair sensory functions and cause neurobehavioral injuries. The olfactory epithelium of fish is arranged in lamellae forming a rosette in the olfactory cavity and contains three main types of olfactory sensory neurons (OSNs): ciliated (cOSNs) and microvillous olfactory sensory neurons (mOSNs), common to all vertebrates, and a third minor group of olfactory neurons, crypt cells, absent in tetrapods. Since copper is a ubiquitously diffusing olfactory toxicant and a spreading contaminant in urban runoff, we investigated the effect of low copper concentration on the three different OSNs in the olfactory epithelium of zebrafish, a model system widely used in biological research. Image analysis was applied for morphometry and quantification of immunohistochemically detected OSNs. Copper exposure resulted in an evident decrease in olfactory epithelium thickness. Moreover, after exposure, the lamellae of the dorsal and ventral halves of the olfactory rosettes showed a different increase in their sensory areas, suggesting a lateral migration of new cells into non-sensory regions. The results of the present study provide clear evidence of a differential response of the three neural cell populations of zebrafish olfactory mucosa after 96 h of exposure to copper ions at the sublethal concentration of 30 µg/L-1. Densitometric values of cONS, immunostained with anti-G αolf, decreased of about 60% compared to the control. When the fish were transferred to water without copper addition and examined after 3, 10 and 30 days, we observed a partial restoration of anti-Gαolf staining intensity to normal condition. The recovery of cOSNs appeared sustained by neuronal proliferation, quantified with anti-PCNA immunostaining, in particular in the early days after exposure. The densitometric analysis applied to mOSNs, immunostained with anti-TRPC2, revealed a statistically significant decrease of about 30% compared to the control. For cOSNs and mOSNs, the decrement in staining intensity may be indicative of cell death, but reduction in antigen expression may not be excluded. In the post-exposure period of 1 month we did not find recovery of mOSNs. We hypothesize that cOSNs are more sensitive than mOSNs to copper treatment, but also more prompted to tissue repair. Anti-TrkA-immunopositive crypt cells appeared not to be affected by copper exposure since statistical analysis excluded any significant difference between the control and treated fish. Comparative studies on OSNs would greatly enhance our understanding of the mechanisms of olfaction.
- Published
- 2017
6. Immunocytochemical characterisation of ensheathing glia in the olfactory and vomeronasal systems of Ambystoma mexicanum (Caudata: Ambystomatidae)
- Author
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Valeria Franceschini, Simone Bettini, Maurizio Lazzari, Lazzari, Maurizio, Bettini, Simone, and Franceschini, Valeria
- Subjects
0301 basic medicine ,Olfactory system ,Histology ,Vomeronasal organ ,Biology ,Receptor, Nerve Growth Factor ,Ambystoma ,Ensheathing cell ,Amphibia ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Animals ,Ambystoma mexicanum ,Spinal Cord Injuries ,Olfactory receptor ,Neuroscience (all) ,General Neuroscience ,Neurogenesis ,Olfactory Pathways ,Immunohistochemistry ,Axons ,Smell ,030104 developmental biology ,medicine.anatomical_structure ,Anamniotes ,nervous system ,Vomeronasal system ,Neural cell adhesion molecule ,Olfactory ensheathing glia ,Vomeronasal Organ ,Anatomy ,Neuroglia ,Neuroscience ,030217 neurology & neurosurgery - Abstract
The olfactory and vomeronasal systems of vertebrates are characterised by neurogenesis occurring throughout life. The regenerative ability of olfactory receptor neurons relies on specific glial cells, the olfactory and vomeronasal axon-surrounding cells. Numerous studies have examined mammalian olfactory ensheathing cells which are considered potential candidates for spinal cord injury repair using cell-based therapy. With regard to non-mammalian vertebrates, limited information is available on these glial cells in fish, and there is no information on them in terrestrial anamniotes, the amphibians. In the present research, we studied the immunocytochemical characteristics of axon-surrounding cells in Ambystoma mexicanum. Urodeles have relatively simple olfactory and vomeronasal systems, and represent a good model for studying ensheathing cells in extant representatives of basal tetrapods. Sections from the decalcified heads of A. mexicanum were immunocytochemically processed for the detection of proteins used in research on mammalian olfactory-ensheathing cells. S100, GFAP and NCAM were clearly observed. p75NTR, Gal-1 and PSA-NCAM showed weak staining. No vimentin immunopositivity was observed. The corresponding areas of the olfactory and vomeronasal pathways displayed the same staining characteristics, with the exception of Gal-1, p75NTR and PSA-NCAM in the mucosae. The degree of marker expression was not uniform throughout the sensory pathways. In contrast to fish, both olfactory and vomeronasal nerves displayed uniform staining intensity. This study showed that some markers for mammalian and fish-ensheathing glia are also applicable in urodeles. The olfactory systems of vertebrates show similarities, and also clear dissimilarities. Further investigations are required to ascertain the functional significance of these regional and interspecific differences.
- Published
- 2016
7. Histopathological analysis of the olfactory epithelium of zebrafish (Danio rerio) exposed to sublethal doses of urea
- Author
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Simone Bettini, Valeria Franceschini, Maurizio Lazzari, Sara Ferrando, Lorenzo Gallus, Bettini, Simone, Lazzari, Maurizio, Ferrando, Sara, Gallus, Lorenzo, and Franceschini, Valeria
- Subjects
0301 basic medicine ,Olfactory system ,medicine.medical_specialty ,Pathology ,Histology ,Evolution ,Gα olf ,Biology ,TRPC2 ,Olfactory Receptor Neurons ,03 medical and health sciences ,chemistry.chemical_compound ,Olfactory mucosa ,0302 clinical medicine ,Olfactory Mucosa ,Behavior and Systematics ,Internal medicine ,medicine ,Animals ,Urea ,PCNA ,Water Pollutants ,Chronic toxicity ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics ,Zebrafish ,Analysis of Variance ,Ecology ,TrkA ,Environmental exposure ,Original Articles ,Cell Biology ,Ecology, Evolution, Behavior and Systematic ,Immunohistochemistry ,Olfactory Bulb ,GTP-Binding Protein alpha Subunits ,Olfactory bulb ,030104 developmental biology ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Toxicity ,Anatomy ,Olfactory epithelium ,030217 neurology & neurosurgery ,Neuroepithelium ,Developmental Biology - Abstract
Chronic renal disease is known to alter olfactory function, but the specific changes induced in olfactory organs during this process remain unclear. Of the uraemic toxins generated during renal disease, high levels of urea are known to induce hyposmic conditions. In this study, the effects of environmental exposure to elevated concentrations of urea (7, 13.5 and 20 g L(-1)) on the sensory mucosa of zebrafish in acute toxicity and chronic toxicity tests were described. It was observed that lamellae maintained structural integrity and epithelial thickness was slightly reduced, but only following exposure to the highest concentrations of urea. Pan-neuronal labelling with anti-Hu revealed a negative correlation with levels of urea, leading to investigation of whether distinct neuronal subtypes were equally sensitive. Using densitometric analysis of immunolabelled tissues, numbers of Gα olf-, TRPC2- and TrkA-expressing cells were compared, representing ciliated, microvillous and crypt neurons, respectively. The three neuronal subpopulations responded differently to increasing levels of urea. In particular, crypt cells were more severely affected than the other cell types, and Gα olf-immunoreactivity was found to increase when fish were exposed to low doses of urea. It can be concluded that exposure to moderate levels of urea leads to sensory toxicity directly affecting olfactory organs, in accordance with the functional olfactometric measurements previously reported in the literature.
- Published
- 2015
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