Papers by Marilyn Getchell
The Annals of otology, rhinology, and laryngology, 1995
The cellular expression of alpha, mu, and pi classes of glutathione S-transferases (GSTs) was inv... more The cellular expression of alpha, mu, and pi classes of glutathione S-transferases (GSTs) was investigated in human nasal mucosa by means of immunocytochemical techniques. In the olfactory mucosa, immunoreactivity for GST-alpha was most intense in the acinar cells of the Bowman's glands, with weak immunoreactivity in the supranuclear region of sustentacular cells. Whereas GST-pi was localized only in the sustentacular cells, no GST-mu was detected. In the respiratory mucosa, GST-alpha and GST-pi were detected at the brush borders of ciliated columnar epithelial cells. There were age- and gender-related trends in the expression of GST-alpha, but not GST-pi, in the olfactory mucosa. The intensity of immunoreactivity in the olfactory mucosa was decreased in older subjects. The expression of GST-alpha in the olfactory mucosa of females consistently exhibited greater intensity than that of males at all the ages studied. These differences were not observed in the respiratory mucosa. T...
BMC bioinformatics, 2005
Cluster analyses are used to analyze microarray time-course data for gene discovery and pattern r... more Cluster analyses are used to analyze microarray time-course data for gene discovery and pattern recognition. However, in general, these methods do not take advantage of the fact that time is a continuous variable, and existing clustering methods often group biologically unrelated genes together. We propose a quadratic regression method for identification of differentially expressed genes and classification of genes based on their temporal expression profiles for non-cyclic short time-course microarray data. This method treats time as a continuous variable, therefore preserves actual time information. We applied this method to a microarray time-course study of gene expression at short time intervals following deafferentation of olfactory receptor neurons. Nine regression patterns have been identified and shown to fit gene expression profiles better than k-means clusters. EASE analysis identified over-represented functional groups in each regression pattern and each k-means cluster, w...
Brain Research, 2002
Numerous in vitro studies of neurogenesis of olfactory receptor neurons (ORNs) suggest that trans... more Numerous in vitro studies of neurogenesis of olfactory receptor neurons (ORNs) suggest that transforming growth factor (TGF)-β promotes the maturation/differentiation of olfactory progenitors. We demonstrate that in vivo both mature and immature ORNs, and possibly a basal neuronal progenitor cell, express the TGF-β type II receptor (TGF-βRII), suggesting that these cells are targets for TGF-β signaling. In a previous study
The Anatomical Record, 1984
Secretory components of the salamander olfactory mucosa, sustentacular cells (SC), and Bowman's g... more Secretory components of the salamander olfactory mucosa, sustentacular cells (SC), and Bowman's glands (BG), were examined histologically and histochemically. In the aquatic larval salamander, SC in sensory grooves contained secretory granules; the submucosa contained a single layer of homogeneous, ductless glands. In the land-dwelling adult salamander, SC spanning a flat epithelial sheet contained vesicles. Subjacent to the epithelium in both dorsal and ventral mucosae lay BG whose ducts opened at the surface of the epithelium. In the ventral mucosa, two additional layers of olfactory glands (OG) lying below the BG were identified; ducts were not observed in association with the OG. The 0-adrenergic agonist isoproterenol caused depletion of secretory granules from BG and OG of larval, young, and adult salamanders but had no discernible effect on SC. Histochemical techniques (Alcian blue at pH 2.5 and pH 1.0, high-iron diamine, and the periodic acid-Schiff reaction) demonstrated that SC contained neutral, acidic, and small amounts of sulfated mucopolysaccharides (MPS). BG and OG contained only neutral MPS. In contrast, glands under adjacent respiratory epithelium contained both acidic and sulfated MPS. Unilateral olfactory nerve section (ONX) caused changes in the histochemical reactivity of acidic and sulfated MPS in SC on the ipsilateral and later on the contralateral side. Neutral MPS staining became enhanced first in the OG that lay under the BG, then in BG cells, and later in the deepest OG layer. Ipsilateral changes preceded contralateral ones. At 24 days post-ONX, some acinar cells in the deep OG contained acidic but not sulfated MPS.
The Anatomical Record, 1991
Lectin histochemistry at the light microscope level was used to determine the distribution of sug... more Lectin histochemistry at the light microscope level was used to determine the distribution of sugar residues in secretory cells of the olfactory mucosae of salamander, hamster, and mouse. Differences in sugar composition and distribution of glycoconjugates found in sustentacular cells and acinar cells of Bowman's glands of these three animals were characterized. Oligosaccharides in secretory products of sustentacular cells in salamander olfactory mucosa contained sialic acid, galactose (Gal), N-acetylgalactosamine (GalNAc), N-acetylglucosamine (GlcNAc), fucose, and mannose residues. Glycoconjugates of these cells lacked terminal galactosyl-beta-(1,3)N-acetylgalactose (Gal beta 1,3GalNAc) residues. The sequences Gal beta 1,3GalNAc, N-acetyllactosamine (Gal beta 1,4GlcNAc), and GalNAc were penultimate to sialic acid residues. Sustentacular cells of mouse and hamster did not appear to contain O-linked oligosaccharides but stained for mannose-containing N-linked oligosaccharides. Glycoconjugates of acinar and duct cells of Bowman's glands in the salamander, hamster, and mouse contained variable amounts of beta(1,4)GlcNAc residues, and terminal N-acetyllactosamine, Gal beta 1,3GalNAc, and GalNAc residues. In the salamander, glycoconjugates of acinar cells possessed terminal GlcNAc residues but were not sialylated, while those of hamster and mouse generally stained for sialic acid but did not possess terminal GlcNAc residues. Secretory products of a subpopulation of rodent acinar cells also contained penultimate Gal beta 1,3GalNAc residues. Staining for sialic acid, Gal, GalNAc, and GlcNAc in glycoconjugates of rodents was often limited to a sub-population of Bowman's glands. This was especially noticeable in the mouse.
The Anatomical Record, 1989
Pharmacological and ultrastructural methods were used to demonstrate alpha-adrenergic regulation ... more Pharmacological and ultrastructural methods were used to demonstrate alpha-adrenergic regulation of secretory granule content of acinar cells of Bowman's glands and to localize and identify adrenergic and cholinergic axonal varicosities and terminals in the olfactory mucosa of the tiger salamander.
Physiology & Behavior, 2006
We have investigated olfactory-mediated pre-ingestive behavior in leptin (ob/ob) and leptin recep... more We have investigated olfactory-mediated pre-ingestive behavior in leptin (ob/ob) and leptin receptor (db/db) mutant mice compared to age-and gender-matched wild-type (wt) mice. Olfactory-mediated behavior was tested using a buried food paradigm 5 times/day at 2-h intervals for 6 days. Mean food-finding times of ob/ob and db/db mice were approximately 10 times shorter than those of wt mice. To test the effect of leptin replacement in ob/ob mice, leptin (1 or 5 μg/g body weight in sterile saline) or carrier was injected i.p. once daily prior to testing. Mean food finding times in ob/ob mice injected with carrier or with 1 μg/g leptin were similar and were 2-3 times faster than in wt mice. Mean food finding times in ob/ob mice injected with 5 μg/g leptin tripled compared to carrier-injected ob/ob mice and were of the same order of magnitude as those of wt mice, suggesting functional leptin replacement. A 3-factor repeated measures ANOVA demonstrated significant differences between the 6 cohorts (P = 0.0001), food finding times (P ≤ 0.0001), and cohort by day interaction (P ≤ 0.0001). Post hoc tests suggested that the ob/ob + 5 μg/g leptin cohort performed more like the wt cohort in the food-finding test than like the ob/ob or ob/ob + carrier cohort. Potential local sites of leptin production and action were identified with immunohistochemistry and in situ hybridization in epithelial and gland cells of the olfactory and nasal mucosae. Our results strongly suggest that leptin acting through leptin receptors modulates olfactory-mediated pre-ingestive behavior.
BMC bioinformatics, 2004
Two or more factor mixed factorial experiments are becoming increasingly common in microarray dat... more Two or more factor mixed factorial experiments are becoming increasingly common in microarray data analysis. In this case study, the two factors are presence (Patients with Alzheimer's disease) or absence (Control) of the disease, and brain regions including olfactory bulb (OB) or cerebellum (CER). In the design considered in this manuscript, OB and CER are repeated measurements from the same subject and, hence, are correlated. It is critical to identify sources of variability in the analysis of oligonucleotide array experiments with repeated measures and correlations among data points have to be considered. In addition, multiple testing problems are more complicated in experiments with multi-level treatments or treatment combinations. In this study we adopted a linear mixed model to analyze oligonucleotide array experiments with repeated measures. We first construct a generalized F test to select differentially expressed genes. The Benjamini and Hochberg (BH) procedure of contr...
BMC bioinformatics, 2006
In gene networks, the timing of significant changes in the expression level of each gene may be t... more In gene networks, the timing of significant changes in the expression level of each gene may be the most critical information in time course expression profiles. With the same timing of the initial change, genes which share similar patterns of expression for any number of sampling intervals from the beginning should be considered co-expressed at certain level(s) in the gene networks. In addition, multiple testing problems are complicated in experiments with multi-level treatments when thousands of genes are involved. To address these issues, we first performed an ANOVA F test to identify significantly regulated genes. The Benjamini and Hochberg (BH) procedure of controlling false discovery rate (FDR) at 5% was applied to the P values of the F test. We then categorized the genes with a significant F test into 4 classes based on the timing of their initial responses by sequentially testing a complete set of orthogonal contrasts, the reverse Helmert series. For genes within each class,...
NeuroReport, 1995
The cellular expression of olfactory marker protein (OMP) mRNA and protein was investigated in th... more The cellular expression of olfactory marker protein (OMP) mRNA and protein was investigated in the olfactory mucosa of humans ranging in age from 26 weeks of gestation to 85 years using in situ hybridization and immunocytochemistry. OMP mRNA and protein were most abundant in the somas of olfactory receptor neurons (ORNs). The hybridization signal over the ORN somal layer was greater in older subjects than in younger ones, reflecting either a higher neuronal density or more OMP mRNA per cell. In contrast, it was significantly lower in subjects with Alzheimer's disease when compared with an age-matched control. Characteristics of older subjects were patchiness in the distribution of OMP-expressing ORNs and the occurrence of subepithelial invaginations containing OMP-positive neurons. In addition, a significant hybridization signal was detected in the apical olfactory epithelium containing the dendrites, dendritic knobs, and cilia of ORNS, and over olfactory nerve bundles in the lamina propria, indicating the occurrence of OMP mRNA in dendritic and axonal domains.
Chemical Senses - CHEM SENSES, 1981
Page 1. Chemical Senses Volume 6 Number 4 1981 Functional correlates of degeneration and renewal ... more Page 1. Chemical Senses Volume 6 Number 4 1981 Functional correlates of degeneration and renewal of cilia and knobs of olfactory receptor neurons in the frog Scott M. Burns, Jerald A. Mitchell, Marilyn L. Getchell and Thomas V. Getchell* ...
Progress in Neurobiology, 1984
In this article we have summarized the basic information which identifies several key issues in t... more In this article we have summarized the basic information which identifies several key issues in the study of perireceptor and receptor events in vertebrate olfaction. We have emphasized the biophysical and biochemical data which have established a pivotal role for the olfactory mucus in the access of odorants to receptor sites as well as their clearance from the micro-environment. In addition, based on initial reports in the literature, we have postulated that the uptake of odorants by cells in the olfactory epithelium and their subsequent enzymatic degradation is an important mechanism in odorant removal. Hence, the pre- and post-interactive events in vertebrate olfaction play a key role in molecular recognition, sensory transduction and receptor desensitization. Study of the primary events in vertebrate olfaction is an increasingly active area of research in neurobiology. Application of contemporary techniques in cell and molecular biology as well as biochemistry and cellular biophysics is yielding new insights into the process and into establishing new hypotheses to be tested.
Physiological Genomics, 2004
The chemokine macrophage inflammatory protein (MIP)-1α recruits macrophages to sites of epithelia... more The chemokine macrophage inflammatory protein (MIP)-1α recruits macrophages to sites of epithelial remodeling. We showed previously that mRNA and protein levels of MIP-1α in the olfactory epithelium (OE) increased significantly at 3 d after bilateral olfactory bulbectomy (OBX). The first aim of this study was to investigate the effect of the absence of MIP-1α on macrophage recruitment to the OE 3 d after OBX in Mip-1α -/mice compared to C57BL/6 mice and to test if chemokine function could be restored by MIP-1α-protein injection into Mip-1α -/mice. OBX was performed on C57BL/6 and Mip-1α -/mice. The mice received 6 injections (s.c.) at 12-h intervals of either 10 µg/ml MIP-1α protein in carrier or carrier only. Macrophage recruitment was evaluated with antibodies to CD68 for all macrophages and F4/80 for activated macrophages. Compared to C57BL/6 mice, at 3 d post-OBX the numbers of CD68 + and F4/80 + macrophages were significantly lower in carrier-injected Mip-1α -/mice and were comparable in MIP-1α protein-injected Mip-1α -/mice. The second aim was to determine the identity of genes regulated at 3 d post-OBX in the OE of carrier-injected Mip-1α -/mice compared with carrierinjected C57BL/6 mice. Total RNA from the OE was hybridized to Affymetrix microarrays. A number of chemokine-, cytokine-, and growth factor-related genes were significantly regulated in the Mip-1α -/mice, and were restored in MIP-1α protein-injected Mip-1α -/mice. The results illustrated that MIP-1α played a key role in recruitment of macrophages to the OE and provided insight into the genomic regulation involved in OE remodeling.
Physiological Genomics, 2007
Resident and recruited olfactory epithelial macrophages participate in the regulation of the surv... more Resident and recruited olfactory epithelial macrophages participate in the regulation of the survival, degeneration, and replacement of olfactory sensory neurons (OSNs). We have reported that liposome-encapsulated clodronate (Lip-C) induced selective and statistically significant depletion of macrophages in the OE of sham and 48 h OBX mice (38 and 35%, respectively) that resulted in increased OSN apoptosis and decreased numbers of mature OSNs and proliferating basal cells compared to controls (Lip-O). The aim of this study was to identify molecular mechanisms by which the selective depletion of macrophages in the OE resulted in these cellular changes by using a microarray expression pattern analysis. A 2ϫ2 ANOVA identified 4,085 overall significantly (P Ͻ 0.01) regulated genes in the OE of Lip-O and Lip-C sham and 48 h OBX mice, and further statistical analysis using pairwise comparisons identified 4,024 genes that had either a significant (P Ͻ 0.01) treatment main effect (n ϭ 2,680), group main effect (n ϭ 778), or interaction effect (n ϭ 980). The mean hybridization signals of immune response genes, e.g., Cxcr4, and genes encoding growth factors and neurogenesis regulators, e.g., Hdgf and Neurod1, respectively, were primarily lower in Lip-C mice compared with Lip-O mice. Apoptosis genes, e.g., Bak1, were also differentially regulated in Lip-C and/or OBX mice. Expression patterns of selected genes were validated with real-time RT-PCR; immunohistochemistry was used to localize selected gene products. These results identified the differential regulation of several novel genes through which alternatively activated macrophages regulate OSN progenitor cell proliferation, differentiation, and maturation, and the survival of OSNs. clodronate; liposomes; microarray; immune response THE DYNAMIC ENVIRONMENT of the olfactory epithelium (OE), where olfactory sensory neurons (OSNs) undergo apoptosis and are replaced from a pool of basal progenitor cells throughout life , continues to provide insight into mechanisms of neuroprotection, neuronal apoptosis, and neurogenesis. More specifically, recent studies (6, 23, 33) on the interaction between the immune system and neurogenesis in the OE have strengthened the case for the participation of macrophages in the regulation of OSN survival and the proliferation, differentiation, and maturation of Address for reprint requests and other correspondence: A. Borders,
Physiological Genomics, 2006
Target ablation (removal of the olfactory bulb, OBX) induces apoptotic death of olfactory sensory... more Target ablation (removal of the olfactory bulb, OBX) induces apoptotic death of olfactory sensory neurons (OSNs) and an immune response in which activation and recruitment of macrophages (m s) into the olfactory epithelium (OE) occupies a central role. M s phagocytose apoptotic neurons and secrete cytokines/growth factors that regulate subsequent progenitor cell proliferation and neurogenesis. Scavenger receptor A (SR-A) is a pattern recognition receptor that mediates binding of m s to apoptotic cells and other relevant immune response functions.
Neuroscience Letters, 1987
Spectrophotometric techniques were used to determine the concentrations of Na +, K + and Ca 2+ in... more Spectrophotometric techniques were used to determine the concentrations of Na +, K + and Ca 2+ in the olfactory mucus of frogs. The mean concentrations in mEq/l were: [Na+], 52.7 + 4.1; [K÷], 10.6 ___ 1.9 and [Ca2+], 10.7 + 1.7. Topical application of the odorant cineole was associated with statistically significant increases in [Na ÷] and [Ca2+]; the secretagogues methacholine and isoproterenol induced transient increases in [Na+]. Cineole and methacholine caused sustained increases in [Na+]/[K +] from the control value of 5:1, while isoproterenol caused a transient increase followed by a decline. The results indicate that the cation concentrations in olfactory mucus samples are more similar to those derived from secretory tissue than to those found in the extracellular fluids surrounding typical neural tissue.
NeuroReport, 1992
The NMa and NMb isoforms of cytochrome P450 enzymes are expressed in three nasal chemosensory org... more The NMa and NMb isoforms of cytochrome P450 enzymes are expressed in three nasal chemosensory organs: the olfactory, septal and vomeronasal mucosae. The NMa isoform is widely distributed throughout the nasal mucosa whereas the NMb isoform is present primarily in the chemosensory mucosae. The localization of cytochromes P450 demonstrates that sustentacular cells in the olfactory and septal epithelia, the mucus of the vomeronasal organ and the acinar cells of glands in the lamina propria of all three chemosensory systems engage in xenobiotic metabolism and participate in odorant/pheromone clearance, a perireceptor process associated with chemosensory transduction.
NeuroReport, 1995
Effects of overexpression of nerve growth factor (NGF) on mast cell phenotype and numbers were in... more Effects of overexpression of nerve growth factor (NGF) on mast cell phenotype and numbers were investigated in nasal and oral mucosae and skin of 3- and 6-week-old transgenic mice in which NGF expression in epithelial basal cells was driven by the keratin-14 promoter. Mast cell phenotypes were identified by Alcian blue/safranin and berberine sulfate histochemistry. In the 3-week-old transgenic mice, NGF overexpression had no effect on phenotype except in tongue, where mast cells exhibited mixed or connective tissue phenotypes compared with the mucosal phenotype in the non-transgenic. In 6-week-old transgenic animals, NGF overexpression resulted in the mucosal phenotype in tissues which contained connective tissue or mixed mast cells in non-transgenics. Mast cell hyperplasia occurred at both ages. NGF effects on mast cell phenotype were age-dependent and involve complex microenvironmental interactions.
NeuroReport, 1993
Immunohistochemical localization of three molecular markers, neuron-specific enolase (NSE) and pr... more Immunohistochemical localization of three molecular markers, neuron-specific enolase (NSE) and protein gene product (PGP) 9.5 for neurons and neuroendocrine cells, and olfactory marker protein (OMP) for olfactory receptor neurons (ORNs) was investigated in the vomeronasal epithelium (VNE) of adult humans. NSE- and PGP 9.5-immunoreactive cells were identified in the VNE. ORNs in the olfactory epithelium of approximately age-matched controls were immunoreactive for the three markers. Most NSE-immunoreactive cells in the VNE were bipolar and similar in shape to the NSE- and PGP 9.5-immunoreactive ORNs. The results indicate that the adult human VNE contains cells expressing two molecular markers characteristic of neurons and that these cells bear a striking morphological similarity to ORNs.
Neurobiology of Aging, 2006
The brain is susceptible to oxidative stress, which is associated with age-related brain dysfunct... more The brain is susceptible to oxidative stress, which is associated with age-related brain dysfunction, because of its high content of peroxidizable unsaturated fatty acids, high oxygen consumption per unit weight, high content of key components for oxidative damage, and the relative scarcity of antioxidant defense systems. Protein oxidation, which results in functional disruption, is not random but appears to be associated with increased oxidation in specific proteins. By using a proteomics approach, we have compared the protein levels and specific protein carbonyl levels, an index of oxidative damage in the brains of old mice, to these parameters in the brains of young mice and have identified specific proteins that are altered as a function of aging. We show here that the expression levels of dihydropyrimidinase-like 2 (DRP2), ␣-enolase (ENO1), dynamin-1 (DNM1), and lactate dehydrogenase 2 (LDH2) were significantly increased in the brains of old versus young mice; the expression levels of three unidentified proteins were significantly decreased. The specific carbonyl levels of -actin (ACTB), glutamine synthase (GS), and neurofilament 66 (NF-66) as well as a novel protein were significantly increased, indicating protein oxidation, in the brains of old versus young mice. These results were validated by immunochemistry. In addition, enzyme activity assays demonstrated that oxidation was associated with decreased GS activity, while the activity of lactate dehydrogenase was unchanged in spite of an up-regulation of LDH2 levels. Several of the up-regulated and oxidized proteins in the brains of old mice identified in this report are known to be oxidized in neurodegenerative diseases as well, suggesting that these proteins may be particularly susceptible to processes associated with neurodegeneration. Our results establish an initial basis for understanding protein alterations that may lead to age-related cellular dysfunction in the brain. (D.A. Butterfield). macromolecules . A number of studies indicate a strong role for increases in protein oxidation as a primary cause of cellular dysfunction observed during aging as well as in agerelated neurodegenerative diseases . The brain is susceptible to oxidative stress because of its high content of peroxidizable unsaturated fatty acids, high oxygen consumption per unit weight, high levels of free radical-inducing iron/ascorbate, and relatively low levels of antioxidant defense systems . In most cases, the oxidation of proteins, including those involved in biosynthesis, energy production, cytoskeletal dynamics, and signal 0197-4580/$ -see front matter
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Papers by Marilyn Getchell