RESUMEN
We recently reported that phogrin, also known as IA-2ß or PTPRN2, forms a complex with the insulin receptor in pancreatic ß cells upon glucose stimulation and stabilizes insulin receptor substrate 2. In ß cells of systemic phogrin gene knockout (IA-2ß-/-) mice, impaired glucose-induced insulin secretion, decreased insulin granule density, and an increase in the number and size of lysosomes have been reported. Since phogrin is expressed not only in ß cells but also in various neuroendocrine cells, the precise impact of phogrin expressed in ß cells on these cells remains unclear. In this study, we performed a comprehensive analysis of morphological changes in RIP-Cre+/-Phogrinflox/flox (ßKO) mice with ß cell-specific phogrin gene knockout. Compared to control RIP-Cre+/- Phogrin+/+ (Ctrl) mice, aged ßKO mice exhibited a decreased density of insulin granules, which can be categorized into three subtypes. While no differences were observed in the density and size of lysosomes and crinosomes, organelles involved in insulin granule reduction, significant alterations in the regions of lysosomes responding positively to carbohydrate labeling were evident in young ßKO mice. These alterations differed from those in Ctrl mice and continued to change with age. These electron microscopic findings suggest that phogrin expression in pancreatic ß cells plays a role in insulin granule homeostasis and crinophagy during aging, potentially through insulin autocrine signaling and other mechanisms.
Asunto(s)
Células Secretoras de Insulina , Insulina , Animales , Ratones , Glucosa/metabolismo , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Proteínas de la Membrana/metabolismo , Ratones NoqueadosRESUMEN
Secretogranin II (SgII) and III (SgIII) function within peptide hormone-producing cells and are involved in secretory granule formation. However, their function in active amine-producing cells is not fully understood. In this study, we analyzed the expression profiles of SgII and SgIII in canine adrenal medulla and pheochromocytomas by immunohistochemical staining. In normal adrenal tissues, the intensity of coexpression of these two secretogranins (Sgs) differed from each chromaffin cell, although a complete match was not observed. The coexpression of vesicular monoamine transporter 2 (VMAT2) with SgIII was similar to that with chromogranin A, but there was a subpopulation of VMAT2-expressing cells that were negative or hardly detectable for SgII. These results are the first to indicate that there are distinct expression patterns for SgII and SgIII in adrenal chromaffin cells. Furthermore, the expression of these two Sgs varied in intensity among pheochromocytomas and did not necessarily correlate with clinical plasma catecholamine levels in patients. However, compared with SgIII, the expression of SgII was shown to be strong at the single-cell level in some tumor tissues. These findings provide a fundamental understanding of the expression differences between SgII and SgIII in normal adrenal chromaffin cells and pheochromocytomas.
Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Células Cromafines , Feocromocitoma , Neoplasias de las Glándulas Suprarrenales/metabolismo , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/veterinaria , Animales , Células Cromafines/metabolismo , Células Cromafines/patología , Cromograninas/metabolismo , Perros , Humanos , Feocromocitoma/metabolismo , Feocromocitoma/patología , Feocromocitoma/veterinaria , Secretogranina II/metabolismoRESUMEN
In the present study, the expression of secretory components and vesicular transport proteins in the canine lacrimal gland was examined and morphometric analysis was performed. The secretory epithelium consists of two types of secretory cells with different morphological features. The secretory cells constituting acinar units (type A cells) exhibited higher levels of glycoconjugates, including ß-GlcNAc, than the other cell type constituting tubular units (type T cells). Immunoblot analysis revealed that antimicrobial proteins, such as lysozyme, lactoferrin and lactoperoxidase, Rab proteins (Rab3d, Rab27a and Rab27b) and soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) proteins (VAMP2, VAMP4, VAMP8, syntaxin-1, syntaxin-4 and syntaxin-6), were expressed at various levels. We immunohistochemically demonstrated that the expression patterns of lysozyme, lactoferrin, Raba27a, Rab27b, VAMP4, VAMP8 and syntaxin-6 differed depending on the secretory cell type. Additionally, in type T cells, VAMP4 was confined to a subpopulation of secretory granules, while VAMP8 was detected in almost all of them. The present study displayed the morphological and histochemical characteristics of the secretory epithelium in the canine lacrimal gland. These findings will help elucidate the species-specific properties of this gland.
Asunto(s)
Aparato Lagrimal/metabolismo , Vesículas Secretoras/metabolismo , Animales , Perros , Epitelio/metabolismo , Aparato Lagrimal/citología , Masculino , Proteínas SNARE/metabolismoRESUMEN
Secretogranin III (SgIII) is a granin protein involved in secretory granule formation in peptide-hormone-producing endocrine cells. In this study, we analyzed the expression of the LacZ reporter in the SgIII knockout mice produced by gene trapping (SgIII-gtKO) for the purpose of comprehensively clarifying the expression patterns of SgIII at the cell and tissue levels. In the endocrine tissues of SgIII-gtKO mice, LacZ expression was observed in the pituitary gland, adrenal medulla, and pancreatic islets, where SgIII expression has been canonically revealed. LacZ expression was extensively observed in brain regions, especially in the cerebral cortex, hippocampus, hypothalamic nuclei, cerebellum, and spinal cord. In peripheral nervous tissues, LacZ expression was observed in the retina, optic nerve, and trigeminal ganglion. LacZ expression was particularly prominent in astrocytes, in addition to neurons and ependymal cells. In the cerebellum, at least four cell types expressed SgIII under basal conditions. The expression of SgIII in the glioma cell lines C6 and RGC-6 was enhanced by excitatory glutamate treatment. It also became clear that the expression level of SgIII varied among neuron and astrocyte subtypes. These results suggest that SgIII is involved in glial cell function, in addition to neuroendocrine functions, in the nervous system.
Asunto(s)
Cromograninas/genética , Operón Lac/genética , Animales , Células Cultivadas , Cromograninas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , RatasRESUMEN
The expression of soluble N-ethyl-maleimide sensitive fusion attachment protein receptor (SNARE) proteins in apocrine glands has not been fully elucidated. In addition to performing ultrastructural observation of the ceruminous glands in goats, our study focuses on the demonstration of ß-defensins, SNARE proteins and Rab3D in these glands with the use of immunohistochemical methods. The secretory cells were equipped with two types of vesicles, Golgi apparatus and abundant rough endoplasmic reticulum (ER). Additionally, in some of them, the characteristic concentric structures composed of rough ER were observed in their circum- and infranuclear parts. The expression of phosphorylated inositol requiring enzyme 1a was also detected. These findings may indicate their ability to produce numerous secretory proteins and the maintenance of homeostasis in the glandular cells. Furthermore, ß-defensins were demonstrated as products of the ceruminous glands. The present investigation also revealed the presence of SNARE proteins and Rab3D. It is suggested that these proteins are concerned with the secretory machinery of this gland type.
Asunto(s)
Glándulas Apocrinas/metabolismo , Proteínas/metabolismo , Proteínas/ultraestructura , Animales , Glándulas Apocrinas/anatomía & histología , Glándulas Apocrinas/ultraestructura , Cerumen/metabolismo , Defensinas/metabolismo , Cabras , Inmunohistoquímica , Proteínas SNARE/metabolismo , Proteínas de Unión al GTP rab3/metabolismoRESUMEN
The comparative structure and expression of salivary components and vesicular transport proteins in the canine major salivary glands were investigated. Histochemical analysis revealed that the morphology of the five major salivary glands-parotid, submandibular, polystomatic sublingual, monostomatic sublingual, and zygomatic glands-was greatly diverse. Immunoblot analysis revealed that expression levels of α-amylase and antimicrobial proteins, such as lysozyme, lactoperoxidase, and lactoferrin, differed among the different glands. Similarly, Rab proteins (Rab3d, Rab11a, Rab11b, Rab27a, and Rab27b) and soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) proteins VAMP4, VAMP8, syntaxin-2, syntaxin-3, syntaxin-4, and syntaxin-6 were expressed at various levels in individual glands. mmunohistochemistry of Rab3d, Rab11b, Rab27b, VAMP4, VAMP8, syntaxin-4, and syntaxin-6 revealed their predominant expression in serous acinar cells, demilunes, and ductal cells. The VAMP4/syntaxin-6 SNARE complex, which is thought to be involved in the maturation of secretory granules in the Golgi field, was found more predominantly in the monostomatic sublingual gland than in the parotid gland. These results suggest that protein expression profiles in canine salivary glands differ among individual glands and reflect the properties of their specialized functions.
Asunto(s)
Proteínas de Unión al ARN/metabolismo , Proteínas SNARE/metabolismo , Glándulas Salivales/metabolismo , Animales , Western Blotting , Perros , Inmunohistoquímica , Inmunoprecipitación , Masculino , Unión Proteica , Proteínas y Péptidos Salivales/metabolismoRESUMEN
PURPOSE: The effects of lumbosacral and spinal orthoses on low back pain and gait are not exactly clear. We previously developed a trunk orthosis with joints providing resistive force on low back load to decrease such load, and confirmed its positive effects during level walking in healthy young adults. Therefore, we aimed to determine the efficacy of this trunk orthosis during level walking in healthy elderly subjects. METHODS: Fifteen community-dwelling elderly subjects performed level walking at a self-selected speed without an orthosis, with our orthosis, and with a lumbosacral orthosis. Kinematic and kinetic data were recorded using a three-dimensional motion analysis system, and erector spinae activity was recorded by electromyography. RESULTS: When comparing the three conditions, our orthosis showed the following effects: it decreased the peak extension moment, increased the peak flexion moment, decreased the lateral bending angle, increased the peak thoracic extension angle, and had significantly lower erector spinae activity and significantly larger peak pelvic forward tilt angles. CONCLUSION: Our orthosis with joints providing resistive force decreased low back load and modified trunk and pelvis alignments during level walking in healthy elderly people.
Asunto(s)
Marcha , Dolor de la Región Lumbar/terapia , Aparatos Ortopédicos , Rango del Movimiento Articular , Caminata , Anciano , Fenómenos Biomecánicos , Electromiografía , Voluntarios Sanos , Humanos , Japón , Región Lumbosacra , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Few studies have examined the efficacy of trunk orthoses that support the upper trunk and a paretic limb in stroke patients. To improve stability and alignment of the trunk and pelvis in hemiparetic patients, we developed a newly designed trunk orthosis that provides resistive force through spring joints. OBJECTIVES: This study aimed to determine the newly designed trunk orthosis's biomechanical effects during level walking. STUDY DESIGN: Before-after trials must be better. METHODS: Measurements were taken for nine chronic-phase (>2 years post-onset) stroke patients using a three-dimensional motion capture system and force plates under three experimental conditions: self-selected gait speed without the newly designed trunk orthosis, with the newly designed trunk orthosis, and after newly designed trunk orthosis removal. We analyzed and compared spatiotemporal and kinetic parameters of the paretic and non-paretic limbs and kinematic parameters of the trunk and bilateral limbs. RESULTS: Several pre-swing gait parameters (e.g. hip joint flexion moment and ankle joint plantar flexion angle) after newly designed trunk orthosis removal were significantly increased compared to those without newly designed trunk orthosis. Step length of the paretic limb tended to increase after newly designed trunk orthosis removal. CONCLUSION: The newly designed trunk orthosis effectively modified trunk alignment, but larger improvements in kinetic and kinematic parameters were observed in the bilateral limbs after newly designed trunk orthosis removal than with the newly designed trunk orthosis. CLINICAL RELEVANCE: Stroke patients improved only trunk malalignment while wearing the newly designed trunk orthosis. Gait after newly designed trunk orthosis removal was better than with the newly designed trunk orthosis. Positive changes after removal were mostly observed in pre-swing of the hemiparetic limb. The newly designed trunk orthosis might be effective for gait training in stroke patients.
Asunto(s)
Diseño de Equipo , Aparatos Ortopédicos , Paresia/rehabilitación , Columna Vertebral/fisiopatología , Rehabilitación de Accidente Cerebrovascular , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Marcha/fisiología , Humanos , Japón , Masculino , Persona de Mediana Edad , Paresia/diagnóstico , Postura/fisiología , Muestreo , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Accidente Cerebrovascular/diagnóstico , Resultado del TratamientoRESUMEN
PURPOSE: Postural alignment of elderly people becomes poor due to aging, possibly leading to low-back pain and spinal deformity. Although there are several interventions for treating these conditions, no previous study has reported the effectiveness of a spinal orthosis or lumbosacral orthosis (LSO) in healthy elderly people without specific spinal deformity. We therefore developed a trunk orthosis to decrease low-back muscle activity while training good postural alignment through resistive force provided by joints with springs (here, called the ORF, which stands for orthosis with joints providing resistive force) as a preventive method against abnormal posture and low-back pain in healthy elderly persons. PATIENTS AND METHODS: Fifteen community-dwelling elderly men participated in this study. Participants stood freely for 10 seconds in a laboratory setting under three conditions: without an orthosis, with the ORF, and with an LSO. The Damen corset LSO was selected as it is frequently prescribed for patients with low-back pain. Postural alignment during static standing was recorded using a three-dimensional motion capture system employing infrared cameras. Two force plates were used to record center of pressure. Electromyograms were obtained for bilateral erector spinae (ES), left internal abdominal oblique, and right gluteus medius muscles. RESULTS: Pelvis forward tilt angle tended to increase while wearing the ORF and decrease while wearing the LSO, but these results were not significant compared to no orthosis. Thorax extension angle and thorax angle on pelvis coordinate system significantly increased while wearing the ORF compared to the other two conditions. ES activity significantly decreased while wearing the ORF compared to the other two conditions. Internal oblique activity was significantly smaller while wearing the LSO than with no orthosis. Center of pressure did not significantly differ among the conditions. CONCLUSION: The ORF significantly improved trunk alignment and decreased ES activity in healthy elderly subjects during static standing.
Asunto(s)
Dorso/fisiología , Dolor de la Región Lumbar/prevención & control , Músculo Esquelético/fisiología , Aparatos Ortopédicos , Postura/fisiología , Anciano , Fenómenos Biomecánicos , Electromiografía , Humanos , Región Lumbosacra/fisiología , Masculino , Tórax/fisiologíaRESUMEN
The expression of secretogranin III (SgIII) in chicken endocrine cells has not been investigated. There is limited data available for the immunohistochemical localization of SgIII in the brain, pituitary, and pancreatic islets of humans and rodents. In the present study, we used immunoblotting to reveal the similarities between the expression patterns of SgIII in the common endocrine glands of chickens and rats. The protein-protein interactions between SgIII and chromogranin A (CgA) mediate the sorting of CgA/prohormone core aggregates to the secretory granule membrane. We examined these interactions using co-immunoprecipitation in chicken endocrine tissues. Using immunohistochemistry, we also examined the expression of SgIII in a wide range of chicken endocrine glands and gastrointestinal endocrine cells (GECs). SgIII was expressed in the pituitary, pineal, adrenal (medullary parts), parathyroid, and ultimobranchial glands, but not in the thyroid gland. It was also expressed in GECs of the stomach (proventriculus and gizzard), small and large intestines, and pancreatic islet cells. These SgIII-expressing cells co-expressed serotonin, somatostatin, gastric inhibitory polypeptide, glucagon-like peptide-1, glucagon, or insulin. These results suggest that SgIII is expressed in the endocrine cells that secrete peptide hormones, which mature via the intragranular enzymatic processing of prohormones and physiologically active amines in chickens.
Asunto(s)
Cromograninas/metabolismo , Glándulas Endocrinas/metabolismo , Secuencia de Aminoácidos , Animales , Encéfalo/metabolismo , Pollos , Femenino , Tracto Gastrointestinal/metabolismo , Masculino , Ratones , Datos de Secuencia Molecular , Especificidad de Órganos , Ratas Wistar , Homología de Secuencia de AminoácidoRESUMEN
BACKGROUND: An ankle-foot orthosis using an oil damper is designed to enable natural movement of the ankle joint. Wearing an ankle-foot orthosis using an oil damper has been demonstrated to assist the first rocker in stroke patients, but its effect on their gait when not wearing it is unclear. OBJECTIVES: To determine the effect of use of ankle-foot orthosis using an oil damper on the gait of stroke patients with hemiparesis when not wearing the ankle-foot orthosis. STUDY DESIGN: Crossover study. METHODS: The gait of eight stroke patients in the chronic phase when not wearing an ankle-foot orthosis was measured, using a three-dimensional motion analysis system, before using the ankle-foot orthosis using an oil damper and then without and with using the ankle-foot orthosis using an oil damper after 3 weeks of use. Differences in gait were compared between the three measurement conditions. RESULTS: Use of ankle-foot orthosis using an oil damper significantly decreased preswing time and significantly increased the positive ankle joint power in stance when not wearing the ankle-foot orthosis using an oil damper. CONCLUSIONS: These changes indicate the promising therapeutic effects of ankle-foot orthosis using an oil damper use and suggest the ankle-foot orthosis using an oil damper's potential as a therapeutic device. CLINICAL RELEVANCE: After 3 weeks of use of an ankle-foot orthosis using an oil damper, which assists the first rocker, the gait of stroke patients in the chronic phase when not wearing the ankle-foot orthosis using an oil damper was improved. Preswing time was significantly decreased and positive ankle joint power was significantly increased. The ankle-foot orthosis using an oil damper, which assists the first rocker function with natural movement of the ankle joint during gait, has the potential to improve the gait of stroke patients after immediate-term use.
Asunto(s)
Tobillo , Diseño de Equipo/instrumentación , Ortesis del Pié , Pie , Marcha/fisiología , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/terapia , Adulto , Anciano , Articulación del Tobillo/fisiología , Fenómenos Biomecánicos/fisiología , Estudios Cruzados , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Movimiento/fisiología , Rango del Movimiento Articular/fisiología , Caminata/fisiologíaRESUMEN
BACKGROUND: The abnormal synergy seen in patients after stroke is considered to limit the ability of these patients. However, in the lower extremity, antigravity torque generation rather than precise movement is needed for functions such as sit-to-stand movement and gait. Therefore, the ability to generate torque may be important either as a primary movement or as an abnormal synergy. We attempted to quantify the torque generation in the lower limb, selectively and as an abnormal synergy, and its relation with gait. METHODS: Selectively generated plantar flexion torque in the ankle and plantar flexion torque secondarily generated accompanying maximal hip extension (i.e., torque generated with abnormal synergy) were measured in subjects after stroke and control subjects. In subjects after stroke, secondary torque generation while controlling hip extension torque as 25%, 50%, and 75% of the maximal hip extension was also measured. The relation of torque generation with the gait speed and timed-up-and go test (TUG) was also analyzed. RESULTS: In subjects after stroke, there was no difference between the amount of plantar flexion torque generated secondarily and the selectively generated torque, whereas the selective torque was significantly greater in control subjects. Pearson product-moment correlation coefficient analysis revealed that TUG speed is related to secondarily generated torque accompanying maximal hip extension but not with selectively generated torque. CONCLUSION: Secondarily generated torque was found to be a factor that affects TUG speed, and the ability to generate torque even through abnormal synergy may help for gait ability in subjects after stroke.
Asunto(s)
Trastornos Neurológicos de la Marcha/fisiopatología , Marcha/fisiología , Accidente Cerebrovascular/fisiopatología , Fenómenos Biomecánicos , Femenino , Humanos , Extremidad Inferior , Masculino , Persona de Mediana Edad , TorqueRESUMEN
The distribution of sialoglycoconjugates and lysozyme in the secretory cells of canine anal glands was studied by means of electron microscopic cytochemical methods, particularly lectin cytochemistry and immunocytochemistry. Sialic acids were predominantly present in the secretory granules, Golgi bodies, surface coat of the plasma membrane and luminal secretions. In addition, within these structures, the secretory granules, Golgi bodies and luminal secretions exhibited high levels of sialoglycoconjugates that terminated in Siaα2-6Gal/GalNAc or Siaα2-3Galß1-4GlcNAc. In the secretory cells, reactive gold particles representing lysozyme were mainly detectable in the secretory granules and Golgi bodies. Sialic acids possess diverging functional properties, whereas lysozyme contributes to the non-specific defense against microorganisms. Therefore, their presence and secretion are suggestive of protective effects of both secretory products at the anal mucosa.
Asunto(s)
Canal Anal/química , Canal Anal/enzimología , Glucolípidos/análisis , Muramidasa/análisis , Canal Anal/citología , Canal Anal/ultraestructura , Animales , Perros , Histocitoquímica , Microscopía Electrónica , Muramidasa/metabolismo , Muramidasa/ultraestructuraRESUMEN
BACKGROUND: An ankle-foot orthosis with an oil damper was previously developed to assist the first rocker function during gait, but the effects of the amount of resistive moment generated on gait have not been clarified. OBJECTIVES: To measure the amount of resistive moment generated by the ankle-foot orthosis with an oil damper during gait and determine its effect on the gait of patients with stroke. STUDY DESIGN: Preliminary cross-sectional study. METHODS: The gait of four patients with stroke in the chronic phase was measured in four conditions: without an ankle-foot orthosis and with the ankle-foot orthosis with an oil damper generating three different amounts of resistive moment. Measurements were taken with a three-dimensional motion analysis system and a specially designed device to determine the resistive moment. RESULTS: The resistive moment was observed in the former half in stance of the paretic limb, and its magnitude was less than 10 N m. Some gait parameters related to terminal stance and preswing were affected by the amount of resistive moment. The forward component of floor reaction force and the shank vertical angle showed peak values when the patients reported feeling most comfortable during gait. CONCLUSION: Although the resistive moment generated by the ankle-foot orthosis with an oil damper was small, it was sufficient to alter gait. CLINICAL RELEVANCE: To maximize the effectiveness of ankle-foot orthoses, it is necessary to know the effects of resistive moment on the gait of patients with stroke. The ankle-foot orthosis with an oil damper assists the first rocker function in gait and also affects the gait in a later phase in stance. The peak values of some gait parameters coincided with patients reporting gait to be most comfortable. It is important to know that ankle-foot orthosis with an oil damper assistance in the first rocker alters the weight acceptance on the paretic limb and affects the gait parameters related to propulsion ability in stance.
Asunto(s)
Articulación del Tobillo/fisiología , Ortesis del Pié , Pie/fisiología , Marcha/fisiología , Rehabilitación de Accidente Cerebrovascular , Anciano , Fenómenos Biomecánicos/fisiología , Estudios Transversales , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Rango del Movimiento Articular/fisiología , Accidente Cerebrovascular/fisiopatología , Resultado del TratamientoRESUMEN
In most mammals except for humanoid primates, eccrine glands are confined to the skin of a series of specific body regions. Sialic acids and antimicrobial substances exhibit various functional properties and serve as a component of nonspecific defense against micro-organisms, respectively. In this study, the distribution of these moieties was studied by electron microscopic histochemical methods. The eccrine glandular acini consisted of two types of dark cells as well as clear cells. The secretory granules and Golgi apparatus of both types of dark cells contained sialic acid residues linked to α2-6Gal/GalNAc. On the other hand, sialoglycoconjugates with Siα2-3Galß1-4GlcNAc sequence were confined to those of the Type II dark cells. In addition, lysozyme and ß-defensin were mainly detected in the secretory granules of the Type II dark cells. These secretory products may create a defensive barrier against microbial invasion and play an essential role in preservation of the integrity of porcine snout skin as a sensory organ.
Asunto(s)
Glándulas Ecrinas/metabolismo , Muramidasa/metabolismo , Ácido N-Acetilneuramínico/química , Piel/metabolismo , beta-Defensinas/metabolismo , Animales , Glándulas Ecrinas/química , Glándulas Ecrinas/enzimología , Glándulas Ecrinas/ultraestructura , Histocitoquímica , Masculino , Microscopía Electrónica , Muramidasa/análisis , Ácido N-Acetilneuramínico/metabolismo , Piel/química , Piel/enzimología , Piel/ultraestructura , Coloración y Etiquetado , Porcinos , Porcinos Enanos , beta-Defensinas/análisisRESUMEN
Islet-associated protein-2 (IA-2) and IA-2ß (also known as phogrin) are unique neuroendocrine-specific protein tyrosine phosphatases (PTPs). The IA-2 family of PTPs was originally identified from insulinoma cells and discovered to be major autoantigens in type 1 diabetes. Despite its expression in the neural and canonical endocrine tissues, data on expression of the IA-2 family of PTPs in gastrointestinal endocrine cells (GECs) are limited. Therefore, we immunohistochemically investigated the expression of the IA-2 family of PTPs in the rat gastrointestinal tract. In the stomach, IA-2 and IA-2ß were expressed in GECs that secrete serotonin, somatostatin, and cholecystokinin/gastrin-1. In addition to these hormones, secretin, gastric inhibitory polypeptide (also known as the glucose-dependent insulinotropic peptide), glucagon-like peptide-1, and glucagon, but not ghrelin were coexpressed with IA-2 or IA-2ß in duodenal GECs. Pancreatic islet cells that secrete gut hormones expressed the IA-2 family of PTPs. The expression patterns of IA-2 and IA-2ß were comparable. These results reveal that the IA-2 family of PTPs is expressed in a cell type-specific manner in rat GECs. The extensive expression of the IA-2 family of PTPs in pancreo-gastrointestinal endocrine cells and in the enteric plexus suggests their systemic contribution to nutritional control through a neuroendocrine signaling network.
Asunto(s)
Células Enteroendocrinas/citología , Inmunohistoquímica , Proteínas Tirosina Fosfatasas Clase 8 Similares a Receptores/análisis , Animales , Anticuerpos , Tracto Gastrointestinal/ultraestructura , Hormonas/análisis , Inmunohistoquímica/métodos , Islotes Pancreáticos/ultraestructura , Masculino , Hipófisis/ultraestructura , Ratas , Ratas Long-EvansRESUMEN
The porcine perianal skin shows prominent apocrine glands with large saccular dilatations, whereby the functional significance of the glandular secretions is rather unexplained. Our study focuses on the demonstration of sialoglycoconjugates and antimicrobial substances in these glands, using glycoconjugate histochemical and immunohistochemical methods. The result obtained emphasized the general presence of sialic acids, linked to α2-6Gal/GalNAc and α2-3Gaßl1-4GlcNAc, in the secretory cells. The secretory epithelium and luminal secretions also contained a spectrum of antimicrobial substances, such as lysozyme, IgA, lactoferrin, and the peptide group of ß-defensins. Realizing that sialic acids possess diverging functional properties through various saccharide residues, and that antimicrobial substances serve as a non-specific defense against microorganisms, these secretory products may function as protective agents in order to preserve the integrity of the perianal region. This view includes that the amounts of bacteria on the skin surface are controlled and maintained at the certain level.
Asunto(s)
Glándulas Perianales/metabolismo , Glándulas Perianales/microbiología , Ácidos Siálicos/metabolismo , Piel/metabolismo , Piel/microbiología , Animales , Glándulas Apocrinas/metabolismo , Glándulas Apocrinas/microbiología , Inmunidad Innata , Inmunohistoquímica , Vías Secretoras , PorcinosRESUMEN
The localization of sialic acids and antimicrobial products (lysozyme, IgA, lactoferrin, ß-defensin 2) as well as Rab3D in the carpal glands of pig was studied by sialoglycoconjugate histochemistry and immunohistochemistry. The secretory epithelium of the carpal glands consisted of dark and clear cells. The dark cells of these glands exhibited high levels of sialoglycoconjugates, including O-acetylated sialic acids, whereas the localization of sialic acids linked to α2-3Gal1-4GlcNAc was confined to a subpopulation of the dark cells. Furthermore, all antimicrobial substances and Rab3D were mainly detectable in a subpopulation of the dark cells. The results obtained are discussed with regard to the functional significance of these glands. Our findings suggested that Rab3D is involved in the secretory regulation of sialoglycoconjugates and antimicrobial substances. These secretory products may create a defensive barrier against microbial invasion and play an essential role in the preservation of skin integrity.
Asunto(s)
Carpo Animal/metabolismo , Glándulas Ecrinas/metabolismo , Ácidos Siálicos/metabolismo , Animales , Carpo Animal/microbiología , Células Cultivadas , Inmunidad Innata , Inmunoglobulina A/metabolismo , Inmunohistoquímica , Lactoferrina/metabolismo , Muramidasa/metabolismo , Especificidad de Órganos , Porcinos , beta-Defensinas/metabolismo , Proteínas de Unión al GTP rab3/metabolismoRESUMEN
Saliva is known to protect the oral cavity and contains glycoproteins and antimicrobial substances. The distribution of these salivary secretions was studied in the labial glands of the Japanese miniature (Shiba) goat using lectin histochemical and immunohistochemical methods. The mucous acinar cells of the labial glands exhibited glycoconjugates with different saccharide residues, such as GalNAcα1-3GalNAc, Galß1-4GalNAc, ß-D-GlcNAc and sialic acid linked to α2-6Gal/GalNAc. Furthermore, α-D-Man, α-L-Fuc, α-D-GalNAc, ß-D-Gal and sialic acid residues were present, in particular, in the serous demilunar cells. Antimicrobial substances (lysozyme, IgA, lactoferrin and ß-defensin) were shown to be mainly immunolocalized in the serous demilunes and duct cells. The results obtained are discussed with regard to the functional role of labial glands. The secretory compounds demonstrated may play an important role in the maintenance of oral health with regard to saliva.
Asunto(s)
Antiinfecciosos/análisis , Glicoconjugados/análisis , Cabras/anatomía & histología , Cabras/metabolismo , Glándulas Salivales Menores/metabolismo , Animales , Inmunoglobulina A/análisis , Inmunohistoquímica , Lactoferrina/análisis , Masculino , Moco/química , Moco/citología , Muramidasa/análisis , Muramidasa/metabolismo , Glándulas Salivales Menores/citología , beta-Defensinas/análisisRESUMEN
The distribution of sialic acids and antimicrobial products (lysozyme, ß-defensin-1, lactoferrin, IgA) in the anal glands of miniature pig was studied by glycoconjugate histochemistry and immunohistochemistry. The glandular acini of these glands exhibited considerable amounts of sialoglycoconjugates that terminated in Siaα2-6Gal/GalNAc or Siaα2-3Gal1-4GlcNAc, including O-acetylated sialic acids. Additionally, all antimicrobial products examined could be demonstrated in the anal glands, especially in the serous cells. The results obtained are discussed with regard to the functional significance of the anal glands. Our observations corroborated the view that sialic acids closely interact with defense cells and antimicrobial substances in the innate immune response. Therefore, the anal glandular secretions may function as protective agents in order to preserve the integrity of the anal region.