scholarly journals Progressive Depletion of Rough Endoplasmic Reticulum in Epithelial Cells of the Small Intestine in Monosodium Glutamate Mice Model of Obesity

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Kazuhiko Nakadate ◽  
Kento Motojima ◽  
Tomoya Hirakawa ◽  
Sawako Tanaka-Nakadate
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Small Intestine ◽  
Epithelial Cells ◽  
Rough Endoplasmic Reticulum ◽  
Defense Mechanism ◽  
Monosodium Glutamate ◽  
Light And Electron Microscopy ◽  
Obese Mice ◽  
Pathological Changes

Chronic obesity is a known risk factor for metabolic syndrome. However, little is known about pathological changes in the small intestine associated with chronic obesity. This study investigated cellular and subcellular level changes in the small intestine of obese mice. In this study, a mouse model of obesity was established by early postnatal administration of monosodium glutamate. Changes in body weight were monitored, and pathological changes in the small intestine were evaluated using hematoxylin-eosin and Nissl staining and light and electron microscopy. Consequently, obese mice were significantly heavier compared with controls from 9 weeks of age. Villi in the small intestine of obese mice were elongated and thinned. There was reduced hematoxylin staining in the epithelium of the small intestine of obese mice. Electron microscopy revealed a significant decrease in and shortening of rough endoplasmic reticulum in epithelial cells of the small intestine of obese mice compared with normal mice. The decrease in rough endoplasmic reticulum in the small intestine epithelial cells of obese mice indicates that obesity starting in childhood influences various functions of the small intestine, such as protein synthesis, and could impair both the defense mechanism against invasion of pathogenic microbes and nutritional absorption.

Development of the lateral palatal brush in larvae of Aedes aegypti (L.) (Diptera: Culicidae)

1990 ◽  
Vol 68 (7) ◽  
pp. 1454-1467 ◽  
Author(s):  
K. M. Fry ◽  
S. B. McIver
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Golgi Apparatus ◽  
Aedes Aegypti ◽  
Rough Endoplasmic Reticulum ◽  
Light And Electron Microscopy ◽  
Fourth Instar ◽  
Muscle Fibres ◽  
Final Length

Light and electron microscopy were used to observe development of the lateral palatal brush in Aedes aegypti (L.) larvae. Development was sampled at 4-h intervals from second- to third-instar ecdyses. Immediately after second-instar ecdysis, the epidermis apolyses from newly deposited cuticle in the lateral palatal pennicular area to form an extensive extracellular cavity into which the fourth-instar lateral palatal brush filaments grow as cytoplasmic extensions. On reaching their final length, the filaments deposit cuticulin, inner epicuticle, and procuticle sequentially on their outer surfaces. The lateral palatal crossbars, on which the lateral palatal brush filaments insert, form after filament development is complete. At the beginning of development, the organelles involved in plasma membrane and cuticle production are located at the base and middle of the cells. As the filament rudiments grow, most rough endoplasmic reticulum, mitochondria, and Golgi apparatus move to the apex of the epidermal cells and into the filament rudiments. After formation of the lateral palatal brush filaments and lateral palatal crossbars, extensive organelle breakdown occurs. Lateral palatal brush formation is unusual in that no digestion and resorption of old endocuticle occurs prior to deposition of new cuticle. No mucopolysaccharide secretion by the lateral palatal brush epidermis was observed, nor were muscle fibres observed to attach to the lateral palatal crossbars, as has been suggested by other workers.

scholarly journals Immunocytochemical localization of actin in epithelial cells of rat small intestine by light and electron microscopy.

1988 ◽  
Vol 36 (7) ◽  
pp. 717-727 ◽  
Author(s):  
S J Hagen ◽  
J S Trier
Keyword(s):  
Electron Microscopy ◽  
Small Intestine ◽  
Epithelial Cells ◽  
Light And Electron Microscopy ◽  
Basal Membrane ◽  
Ground Substance ◽  
Structural Protein ◽  
Thin Sections ◽  
Filament Bundles ◽  
Lowicryl K4m

We used post-embedding immunocytochemical techniques and affinity-purified anti-actin antibody to evaluate localization of actin in epithelial cells of small intestine by fluorescence and electron microscopy. Small intestine was fixed with 2% formaldehyde-0.1% glutaraldehyde and embedded in Lowicryl K4M. One-micron or thin sections were stained with antibody followed by rhodamine- or colloidal gold-labeled goat anti-rabbit IgG, respectively. Label was present overlying microvilli, the apical terminal web, and the cytoplasm directly adjacent to occluding and intermediate junctions. Label was associated with outer mitochondrial membranes of all cells and the supranuclear Golgi region of goblet cells. Lateral cytoplasmic interdigitations between mature cells and subplasmalemmal filaments next to intrusive cells were densely labeled. The cytoplasm adjacent to unplicated domains of lateral membrane was focally labeled. Label was prominent over organized filament bundles within the subplasmalemmal web at the base of mature cells, whereas there was focal labeling of the cytoplasm adjacent to the basal membrane of undifferentiated cells. Basolateral epithelial cell processes were labeled. Label was focally present overlying the cellular ground substance. Our results demonstrate that actin is distributed in a distinctive fashion within intestinal epithelial cells. This distribution suggests that in addition to its function as a structural protein, actin may participate in regulation of epithelial tight junction permeability, in motile processes including migration of cells from the crypt to the villus tip, in accommodation of intrusive intraepithelial cells and in adhesion of cells to one another and to their substratum.

Membranous Structures Directly Come in Contact With p62/SQSTM1 Bodies

2021 ◽  
pp. 002215542110114
Author(s):  
Isei Tanida ◽  
Tomohiro Haruta ◽  
Mitsuo Suga ◽  
Shunsuke Takei ◽  
Akira Takebe ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Click Chemistry ◽  
Rough Endoplasmic Reticulum ◽  
Unique Feature ◽  
Light And Electron Microscopy ◽  
Adaptor Protein

During autophagy, autophagosomes are formed to engulf cytoplasmic contents. p62/SQSTM-1 is an autophagic adaptor protein that forms p62 bodies. A unique feature of p62 bodies is that they seem to directly associate with membranous structures. We first investigated the co-localization of mKate2-p62 bodies with phospholipids using click chemistry with propargyl-choline. Propargyl-choline-labeled phospholipids were detected inside the mKate2-p62 bodies, suggesting that phospholipids were present inside the bodies. To clarify whether or not p62 bodies come in contact with membranous structures directly, we investigated the ultrastructures of p62 bodies using in-resin correlative light and electron microscopy of the Epon-embedded cells expressing mKate2-p62. Fluorescent-positive p62 bodies were detected as uniformly lightly osmificated structures by electron microscopy. Membranous structures were detected on and inside the p62 bodies. In addition, multimembranous structures with rough endoplasmic reticulum–like structures that resembled autophagosomes directly came in contact with amorphous-shaped p62 bodies. These results suggested that p62 bodies are unique structures that can come in contact with membranous structures directly:

scholarly journals Small intestine barrier function failure induces systemic inflammation in monosodium glutamate-induced chronically obese mice

2019 ◽  
Vol 44 (6) ◽  
pp. 587-594 ◽  
Author(s):  
Kazuhiko Nakadate ◽  
Tomoya Hirakawa ◽  
Sawako Tanaka-Nakadate
Keyword(s):  
Small Intestine ◽  
Epithelial Cells ◽  
Systemic Inflammation ◽  
Intestinal Epithelial Cells ◽  
Monosodium Glutamate ◽  
Intestinal Epithelial ◽  
Obese Mice ◽  
Gastrointestinal Barrier ◽  
Small Intestinal ◽  
Functional Deterioration

Chronic obesity has increased worldwide, in conjunction with type 2 diabetes. Chronic obesity causes systemic inflammation that may result in functional deterioration of the gastrointestinal barrier. However, gastrointestinal conditions associated with chronic obesity have not been comprehensively investigated. The purpose of this study was to evaluate morphological changes in small intestine barrier structures during chronic obesity. A mouse model of chronic obesity induced by monosodium glutamate treatment was established. At postnatal week 15, pathological changes including in small intestinal epithelial cells were analyzed in chronically obese mice compared with controls. Numerous gaps were identified between small intestinal epithelial cells in chronically obese mice, and levels of both desmosomal and tight junction proteins were significantly lower in their small intestinal epithelial cells. Moreover, in chronically obese mice, a significant increase in the number of intestinal inflammatory cells, particularly macrophages, was observed; in addition, blood samples from the mouse model show an increase in markers of inflammation, tumor necrosis factor-alpha and interleukin-1-beta. These findings suggest that functional deterioration of adhesion structures between small intestinal epithelial cells causes gastrointestinal barrier function failure, leading to a rise in intestinal permeability to blood vessels and consequent systemic inflammation, characterized by macrophage infiltration.

Morphology and ontogeny of tannin-producing structures in two tropical legume trees

Botany ◽  
2014 ◽  
Vol 92 (7) ◽  
pp. 513-521 ◽  
Author(s):  
Thais Cury de Barros ◽  
Simone Pádua Teixeira
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Rough Endoplasmic Reticulum ◽  
Light And Electron Microscopy ◽  
Stages Of Development ◽  
Tropical Legume ◽  
Legume Trees ◽  
Vegetative Buds ◽  
Tannin Cells

Two legume trees largely known as tannin producers — Dimorphandra mollis Benth. (Caesalpinioideae) and Stryphnodendron adstringens (Mart.) Coville (Mimosoideae) — were used as models to elucidate the morphology and ontogeny of tannin cells. Vegetative parts of plants were processed for observation using light and electron microscopy (scanning and transmission). Idioblasts, found even in young plants of both species, and secretory trichomes, observed in vegetative buds of mature plants of S. adstringens, are responsible for tannin production. The tanniniferous idioblasts originate from protoderm and also from ground meristem cells. The ground meristem proved to be the best place to study the development of tanniniferous idioblasts at different stages of development, which allowed us to monitor the production and accumulation of tannins in the same tissue. Our data indicate that there is a relationship between the production of tannins and the process of vacuolation of tanniniferous cells. The results also indicate the probable performance of rough endoplasmic reticulum (RER) and plastids in the production of tannins.

scholarly journals Gnotobiotic Piglets Experimentally Infected with Neonatal Calf Diarrhoea Reovirus-Like Agent (Rotavirus)

1976 ◽  
Vol 13 (3) ◽  
pp. 197-210 ◽  
Author(s):  
G. A. Hall ◽  
Janice C. Bridger ◽  
R. L. Chandler ◽  
G. N. Woode
Keyword(s):  
Electron Microscopy ◽  
Small Intestine ◽  
Epithelial Cells ◽  
Light And Electron Microscopy ◽  
Severe Damage ◽  
Severe Stunting ◽  
Virus Particles ◽  
Stomach Mucosa ◽  
Neonatal Calf ◽  
Gnotobiotic Piglets

Gnotobiotic piglets were infected with a strain of rotavirus that had been isolated from a calf and passaged four times in piglets. The resulting disease was studied by light and electron microscopy at 21, 44 and 68h after inoculation. In the small intestine infection caused desquamation of the epithelial cells of the villi resulting in severe stunting. There was severe damage to microvilli and accumulation of lipid within the cytoplasm. Virus particles were seen in epithelial cells covering the stunted villi. Infection also caused desquamation of the superficial epithelial cells of the stomach mucosa and of the epithelial cells of the bronchi, bronchioles, and alveoli of the lungs.

scholarly journals Distribution of Heavy Metals in the Liver of Foetuses and Female Mice after Oral Administration during Pregnancy - a Histochemical Study

2010 ◽  
Vol 79 (2) ◽  
pp. 225-231 ◽  
Author(s):  
Lenka Krejčířová ◽  
Irena Lauschová ◽  
Petr Čížek
Keyword(s):  
Electron Microscopy ◽  
Heavy Metals ◽  
Endoplasmic Reticulum ◽  
Oral Administration ◽  
Rough Endoplasmic Reticulum ◽  
Morphological Changes ◽  
Light And Electron Microscopy ◽  
Central Vein ◽  
Cell Nuclei ◽  
Female Mice

The aim of this work was to study the distribution of heavy metals and of subsequently developed morphological changes in the liver of female mice and their foetuses after oral administration of high doses of lead, mercury, and cadmium (0.03 mg of metal per mouse and day). Heavy metals were administered to pregnant female mice on days 9-20 of pregnancy. The animals were euthanised by cervical dislocation. Samples of mother and foetal liver were subsequently collected and processed by means of the common technique for light and electron microscopy. Histochemical reaction based on metal conversion into appropriate sulphide that conjugates with silver was used for detection of heavy metals. Deposits of heavy metals were found at the periphery of lobules of the central vein in the liver of female mice. On the contrary, in the liver of foetuses no predilection site for localisation of the reaction product could be identified. At the electron microscopy level, accumulation of heavy metals was connected as a rule with the occurrence of certain damage to some organelles. Deposits of the reaction product were located mainly in hepatocytes and Kupffer cells. Heavy metals were bound to the heterochromatin of cell nuclei, as well as to some cytoplasmic organelles, such as rough endoplasmic reticulum, mitochondria, ribosomes, and lysosomes. The presence of heavy metals was associated with obliteration of cisternae of the rough endoplasmic reticulum, separation of ribosomes, and destruction of lysosomes. Vacuolation of cell cytoplasm was also a frequent phenomenon. An interesting finding was the "contrasting" of structures containing nucleic acids. Accumulation of metals in the liver of pregnant mice and their foetuses observed in our study indicated that placental barrier does not protect the foetal organism against penetration of metals. Their higher accumulation in foetal compared to maternal liver can be explained by the intense metabolism of differentiating hepatocytes.

Modification of Pineal Ultrastructure by Exogenous Hormones

1967 ◽  
Vol 25 ◽  
pp. 170-171
Author(s):  
R. A. Turner ◽  
A. E. Rodin ◽  
D. K. Roberts
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Rough Endoplasmic Reticulum ◽  
Estradiol Benzoate ◽  
Female Rats ◽  
List Type ◽  
Type Number ◽  
Pregnant Rats ◽  
Gonadal Atrophy ◽  
Pineal Ultrastructure

There have been many reports which establish a relationship between the pineal and sexual structures, including gonadal hypertrophy after pinealectomy, and gonadal atrophy after injection of pineal homogenates or of melatonin. In order to further delineate this relationship the pineals from 5 groups of female rats were studied by electron microscopy:ControlsPregnant ratsAfter 4 weekly injections of 0.1 mg. estradiol benzoate.After 8 daily injections of 150 mcgm. melatonin (pineal hormone).After 8 daily injections of 3 mg. serotonin (melatonin precursor).No ultrastructural differences were evident between the control, and the pregnancy and melatonin groups. However, the estradiol injected animals exhibited a marked increase in the amount and size of rough endoplasmic reticulum within the pineal cells.

scholarly journals Effects of the cationic protein poly-L-arginine on airway epithelial cellsin vitro

2002 ◽  
Vol 11 (3) ◽  
pp. 141-148 ◽  
Author(s):  
Shahida Shahana ◽  
Caroline Kampf ◽  
Godfried M. Roomans
Keyword(s):  
Electron Microscopy ◽  
Epithelial Cells ◽  
Cell Membrane ◽  
Cell Damage ◽  
Membrane Damage ◽  
Light And Electron Microscopy ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Cationic Protein ◽  
Induced Apoptosis

Background: Allergic asthma is associated with an increased number of eosinophils in the airway wall. Eosinophils secrete cationic proteins, particularly major basic protein (MBP).Aim: To investigate the effect of synthetic cationic polypeptides such as poly-L-arginine, which can mimic the effect of MBP, on airway epithelial cells.Methods: Cultured airway epithelial cells were exposed to poly-L-arginine, and effects were determined by light and electron microscopy.Results: Poly-L-arginine induced apoptosis and necrosis. Transmission electron microscopy showed mitochondrial damage and changes in the nucleus. The tight junctions were damaged, as evidenced by penetration of lanthanum. Scanning electron microscopy showed a damaged cell membrane with many pores. Microanalysis showed a significant decrease in the cellular content of magnesium, phosphorus, sodium, potassium and chlorine, and an increase in calcium. Plakoglobin immunoreactivity in the cell membrane was decreased, indicating a decrease in the number of desmosomes.Conclusions: The results point to poly-L-arginine induced membrane damage, resulting in increased permeability, loss of cell-cell contacts and generalized cell damage.

Phase-contrast and electron-microscopic observations on a membranous complex in primary spermatocytes of the mouse

1975 ◽  
Vol 18 (1) ◽  
pp. 1-17
Author(s):  
A. Pleshkewych ◽  
L. Levine
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Phase Contrast ◽  
Cultured Cells ◽  
Light And Electron Microscopy ◽  
Cytoplasmic Inclusion ◽  
Electron Microscopic ◽  
Secondary Spermatocyte ◽  
Living Mouse ◽  
Circular Contour

A prominent cytoplasmic inclusion present in living mouse primary spermatocytes has been observed by both light and electron microscopy. It began to form at prometaphase and continued to increase in thickness and length as the cells developed. By metaphase it was a distinct sausage-shaped boundary that enclosed a portion of the cytoplasm between the spindle and the cell membrane. At the end of metaphase, the inclusion reached its maximum length. At telophase, it was divided between the daughter secondaries. The inclusion persisted as a circular contour in the interphase secondary spermatocyte. Electron microscopy of the same cultured cells that were previously observed with light microscopy revealed that the inclusion was a distinctive formation of membranes. It consisted of agranular cisternae and vesicles, and was therefore a membranous complex. Many of the smaller vesicles in the membranous complex resembled those found in the spindle. The cisternae in the membranous complex were identical to the cisternal endoplasmic reticulum of interphase primary spermatocytes. Nevertheless, the organization of vesicles and cisternae into the membranous complex was unique for the primaries in division stages, since such an organization was not present in their interphase stages.

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