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Edna Freymuller - One of the best experts on this subject based on the ideXlab platform.
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Testosterone modulation of the male marsupial Metachirus nudicaudatus paracloacal (scent) glands
Zoomorphology, 2016Co-Authors: Manuel Jesus Simões, Edna FreymullerAbstract:We investigated the possible influence of androgens on the odoriferous (scent) glands of the neotropical male marsupial Metachirus nudicaudatus . Glands of control animals from wild populations in the breeding and non-breeding seasons were compared with the ones of castrated animals. Radioimmunoassay was used to detect testosterone levels in all studied groups. When compared with the major (yellow) and the minor (brown) glands in the breeding season, the yellow gland was larger in two of three animals. In the non-breeding season, they were closely the same size, whereas in castrated animals, the major glands were smaller than the minor ones. The number of layers of the Holocrine secretory epithelium and the mean cell area of the major (yellow) gland were also well developed in the breeding season (8–12 layers) in contrast to non-breeding (1–9 layers) and castrated animals (1–5 layers). There was no significant difference in the minor (brown) gland concerning the gland volume and the number of layers of the Holocrine secretory epithelium in all surveyed groups. The mean cellular areas of tubular glands inserted in yellow glands of the breeding season were larger than those in the non-breeding season and castrated subjects. On the other hand, some variations observed in the average cell areas of the brown glands did not obey the standard of testosterone activity. In conclusion, the major (yellow) paracloacal gland of Metachirus nudicaudatus males is under the influence of testosterone, while the minor (brown) gland is not.
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Morphophysiology of the paracloacal (scent) glands in females of the marsupial Metachirus nudicaudatus: action of estrogens
Zoomorphology, 2014Co-Authors: Erasmo Garcia Mendes, Manuel Jesus Simões, Nancy Marques Carneiro, Edna FreymullerAbstract:The histophysiology of both brown and yellow paracloacal glands of control animals from wild populations was analyzed in the breeding and non-breeding seasons and in oophorectomized animals. The effect of estrogens on the scent glands of female Metachirus nudicaudatus was investigated. Radioimmunoassay indicated that estradiol levels in the breeding season were high, while those in the non-breeding season and oophorectomized had minute amounts. No apparent change in gland volume was observed in the various animal groups. Light microscopy showed a wide variation in the number of layers of the Holocrine secretory epithelium of the major (brown) gland between the breeding (1–7) and non-breeding season (8–19) and in oophorectomized (8–18) animals. The minor (yellow) gland showed the most evident variation: the Holocrine epithelium was restricted to the basal layer in the breeding season, but was restored and exhibited up to eight layers in the non-breeding season and in oophorectomized females. The mean cellular area of the secretory Holocrine epithelium in the breeding season was smaller than in the non-breeding period and in castrated animals. On the other hand, the mean cellular areas of tubular glands inserted in both yellow and brown glands in the breeding season were larger than those in the non-breeding season and after castration. The results consistently indicate that the glandular volumes of yellow and brown glands do not depend on estrogens, whereas the Holocrine secretory epithelium and tubular glands of both are estrogenic modulation.
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A MORPHOLOGICAL AND ULTRASTRUCTURAL STUDY OF THE PARACLOACAL (SCENT) GLANDS OF THE MARSUPIAL METACHIRUS NUDICAUDATUS GEOFFROY, 1803
Cells Tissues Organs, 1995Co-Authors: Helder-jose, Edna FreymullerAbstract:Morphological and ultrastructural features of the paracloacal glands of Metachirus nudicaudatus are described. Two pairs of glands, one on the right and the other on the left of the anal canal, are formed, each consisting of a major and a minor portion. Their wall is made up of three layers: a mucosal, a muscular and an external capsule. The inner one is a mucosa the epithelium of which contains Holocrine cells characterized by lipid droplets and intermediate filaments. The surrounding vascular lamina propria contains flattened tubular apocrine glands whose epithelial cells contain abundant endoplasmic reticulum, prominent Golgi complexes and numerous secretory granules. The middle layer is formed by skeletal striated muscle and the outer (third layer) consists of dense connective tissue. Each gland originates from a single duct. Transverse sections show that each duct, except in the female major gland, is in fact formed by a duct system. One of these ducts comes from the central cavity, lined by Holocrine epithelium, and the others result from the branched tubular glands of the lamina propria.
Conor L. Evans - One of the best experts on this subject based on the ideXlab platform.
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longitudinal 3d in vivo imaging of sebaceous glands by coherent anti stokes raman scattering microscopy normal function and response to cryotherapy
Journal of Investigative Dermatology, 2015Co-Authors: Yookyung Jung, Rox R Anderson, Ray H Jalian, Conor L. EvansAbstract:Sebaceous glands perform complex functions, and they are centrally involved in the pathogenesis of acne vulgaris. Current techniques for studying sebaceous glands are mostly static in nature, whereas the gland’s main function—excretion of sebum via the Holocrine mechanism—can only be evaluated over time. We present a longitudinal, real-time alternative—the in vivo, label-free imaging of sebaceous glands using Coherent Anti-Stokes Raman Scattering (CARS) microscopy, which is used to selectively visualize lipids. In mouse ears, CARS microscopy revealed dynamic changes in sebaceous glands during the Holocrine secretion process, as well as in response to damage to the glands caused by cooling. Detailed gland structure, plus the active migration of individual sebocytes and cohorts of sebocytes, were measured. Cooling produced characteristic changes in sebocyte structure and migration. This study demonstrates that CARS microscopy is a promising tool for studying the sebaceous gland and its associated disorders in three dimensions in vivo.
Ray H Jalian - One of the best experts on this subject based on the ideXlab platform.
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longitudinal 3d in vivo imaging of sebaceous glands by coherent anti stokes raman scattering microscopy normal function and response to cryotherapy
Journal of Investigative Dermatology, 2015Co-Authors: Yookyung Jung, Rox R Anderson, Ray H Jalian, Conor L. EvansAbstract:Sebaceous glands perform complex functions, and they are centrally involved in the pathogenesis of acne vulgaris. Current techniques for studying sebaceous glands are mostly static in nature, whereas the gland’s main function—excretion of sebum via the Holocrine mechanism—can only be evaluated over time. We present a longitudinal, real-time alternative—the in vivo, label-free imaging of sebaceous glands using Coherent Anti-Stokes Raman Scattering (CARS) microscopy, which is used to selectively visualize lipids. In mouse ears, CARS microscopy revealed dynamic changes in sebaceous glands during the Holocrine secretion process, as well as in response to damage to the glands caused by cooling. Detailed gland structure, plus the active migration of individual sebocytes and cohorts of sebocytes, were measured. Cooling produced characteristic changes in sebocyte structure and migration. This study demonstrates that CARS microscopy is a promising tool for studying the sebaceous gland and its associated disorders in three dimensions in vivo.
Yookyung Jung - One of the best experts on this subject based on the ideXlab platform.
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longitudinal 3d in vivo imaging of sebaceous glands by coherent anti stokes raman scattering microscopy normal function and response to cryotherapy
Journal of Investigative Dermatology, 2015Co-Authors: Yookyung Jung, Rox R Anderson, Ray H Jalian, Conor L. EvansAbstract:Sebaceous glands perform complex functions, and they are centrally involved in the pathogenesis of acne vulgaris. Current techniques for studying sebaceous glands are mostly static in nature, whereas the gland’s main function—excretion of sebum via the Holocrine mechanism—can only be evaluated over time. We present a longitudinal, real-time alternative—the in vivo, label-free imaging of sebaceous glands using Coherent Anti-Stokes Raman Scattering (CARS) microscopy, which is used to selectively visualize lipids. In mouse ears, CARS microscopy revealed dynamic changes in sebaceous glands during the Holocrine secretion process, as well as in response to damage to the glands caused by cooling. Detailed gland structure, plus the active migration of individual sebocytes and cohorts of sebocytes, were measured. Cooling produced characteristic changes in sebocyte structure and migration. This study demonstrates that CARS microscopy is a promising tool for studying the sebaceous gland and its associated disorders in three dimensions in vivo.
Ana Cotomontes - One of the best experts on this subject based on the ideXlab platform.
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analysis of constant tissue remodeling in syrian hamster harderian gland intra tubular and inter tubular syncytial masses
Journal of Anatomy, 2013Co-Authors: Ana Cotomontes, Russel J Reiter, Beatriz Caballero, Veronica Sierra, Marina Garciamacia, Maria Josefa Rodriguezcolunga, Ignacio VeganaredoAbstract:The Syrian hamster Harderian gland (HG) has a marked sexual dimorphism and exhibits an extraordinary rate of porphyrinogenesis. The physiological oxidative stress, derived from constant porphyrin production, is so high that the HG needs additional survival autophagic mechanisms to fight against this chronic exposure, provoking the triggering of a Holocrine secretion in female glands that forms two types of secretory masses: intra-tubular-syncytial and inter-tubular-syncytial masses. The aim of this work was to study the development of this inter-tubular Holocrine secretion. To approach this task, we have considered that the steps developed during the formation of the so-called invasive masses consist of the growth of epithelial cells, cell detachment from the basal lamina and invasion of surrounding tissues. The presence of these masses, particularly in the female HG, are closely linked to sexual dimorphism in redox balance and to alterations in the expression of certain factors such as cytokeratins, P-cadherin, matrix metalloproteinases, cathepsin H, proliferating cell nuclear antigen, p53, CD-31 and vascular endothelial growth factor, which seem to be involved in tissue remodeling. The results document unusual mechanisms of secretion in Syrian hamster HG: an extraordinary system of massive secretion through the conjunctive tissue, disrupting the branched structure of the gland.
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sexual dimorphism of autophagy in syrian hamster harderian gland culminates in a Holocrine secretion in female glands
Autophagy, 2009Co-Authors: Ignacio Veganaredo, Beatriz Caballero, Veronica Sierra, Covadonga Huidobrofernandez, David De Gonzalocalvo, Marina Garciamacia, Delio Tolivia, Maria Josefa Rodriguezcolunga, Ana CotomontesAbstract:The Syrian hamster Harderian gland (HG) has a large porphyrin metabolism with a sexual dimorphism, showing male HGs much lower porphyrin concentrations than female glands. Damage derived from this production of porphyrins, displayed by reactive oxygen species, forces the gland to develop morphological changes that must have a physiological significance. Thus, oxidative stress is present in two states: mild oxidative stress in male HGs and extreme oxidative stress in female HGs. Cathepsins data gave indirect indications about the presence of programmed cell death affecting the lysosomal pathway, especially in female HGs, which showed an accumulation of autophagic bodies. Our results showed different degrees of autophagy in Syrian hamster HGs depending on sex and probably controlled by the redox-sensitive transcription factors: NF-kappaB and p53. The discovery of these sexual dimorphisms in redox signaling and in autophagy corroborates previous findings and underlines the key role of reactive oxygen species...