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1.
Rev. esp. investig. quir ; 25(3): 97-102, 2022. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-211158

RESUMO

El páncreas es un órgano de origen endodérmico, que se desarrolla de dos esbozos intestinales separados, uno dorsal y otro ventral,a partir de la cuarta o quinta semana de gestación. El páncreas se origina en el intestino anterior en la parte correspondiente a lafutura segunda porción duodenal. Allí se originan dos brotes: uno posterior o dorsal que aparece a principios de la cuarta semanay crece rápidamente en el mesenterio dorsal y el otro brote es anterior o ventral. Este último da origen a dos brotes, uno origina unaparte del páncreas y otro a la vía biliar e hígado. Existen diferentes variantes anatómicas, derivadas de este desarrollo embrionario;su conocimiento es de vital importancia en pacientes con persistencia de dolor abdominal y episodios de pancreatitis recurrente.El objetivo de este artículo es una revisión de las variantes anatómicas del conducto pancreático que pueden manifestarse como pancreatitis idiopática recurrente. (AU)


The pancreas is an organ of endodermal origin, which develops from two separate intestinal sketches, one dorsal and one ventral,from the fourth or fifth week of gestation. The pancreas originates in the anterior intestine in the part corresponding to the futuresecond duodenal portion. There two shoots originate: one posterior or dorsal that appears at the beginning of the fourth week andgrows rapidly in the dorsal mesentery and the other outbreak is anterior or ventral. The latter gives rise to two outbreaks, oneoriginates a part of the pancreas and another to the bile duct and liver. There are different anatomical variants, derived from thisembryonic development; their knowledge is of vital importance in patients with persistent abdominal pain and episodes of recurrentpancreatitis. The objective of this article is a review of the anatomical variants of the pancreatic duct that can manifest as recurrent idiopathic pancreatitis. (AU)


Assuntos
Humanos , Pâncreas/anormalidades , Pâncreas/anatomia & histologia , Pâncreas/crescimento & desenvolvimento , Pâncreas/ultraestrutura , Ductos Pancreáticos/anormalidades , Ductos Pancreáticos/anatomia & histologia , Ductos Pancreáticos/crescimento & desenvolvimento , Ductos Pancreáticos/ultraestrutura
2.
Sci Rep ; 11(1): 17220, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446743

RESUMO

Primary cilia protrude from the apical surface of many cell types and act as a sensory organelle that regulates diverse biological processes ranging from chemo- and mechanosensation to signaling. Ciliary dysfunction is associated with a wide array of genetic disorders, known as ciliopathies. Polycystic lesions are commonly found in the kidney, liver, and pancreas of ciliopathy patients and mouse models. However, the pathogenesis of the pancreatic phenotype remains poorly understood. Chibby1 (Cby1), a small conserved coiled-coil protein, localizes to the ciliary base and plays a crucial role in ciliogenesis. Here, we report that Cby1-knockout (KO) mice develop severe exocrine pancreatic atrophy with dilated ducts during early postnatal development. A significant reduction in the number and length of cilia was observed in Cby1-KO pancreta. In the adult Cby1-KO pancreas, inflammatory cell infiltration and fibrosis were noticeable. Intriguingly, Cby1-KO acinar cells showed an accumulation of zymogen granules (ZGs) with altered polarity. Moreover, isolated acini from Cby1-KO pancreas exhibited defective ZG secretion in vitro. Collectively, our results suggest that, upon loss of Cby1, concomitant with ciliary defects, acinar cells accumulate ZGs due to defective exocytosis, leading to cell death and progressive exocrine pancreatic degeneration after birth.


Assuntos
Proteínas de Transporte/genética , Cílios/metabolismo , Pâncreas Exócrino/metabolismo , Pâncreas/metabolismo , Pancreatite/genética , Células Acinares/metabolismo , Animais , Atrofia , Proteínas de Transporte/metabolismo , Ciliopatias/genética , Ciliopatias/metabolismo , Exocitose/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Pâncreas/patologia , Pâncreas/ultraestrutura , Pâncreas Exócrino/patologia , Pancreatite/metabolismo , Vesículas Secretórias/metabolismo
3.
PLoS One ; 16(8): e0255733, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34388180

RESUMO

We previously reported that dye was effective to prevent the leakage of enzyme solutions from pancreatic glands during an islet isolation procedure. However, the dye used for islet isolation has not yet been optimized. In this study, we focused on pyoktanin blue (PB), diagnogreen (DG), and indigo carmine (IC) as potential candidates among clinically established dyes. A serial dilution assay was performed to determine minimal effective concentrations of each dye for detecting damaged pancreatic tissues. According to the outcome of serial dilution assays, double minimum effective concentrations of each dye were used for in vitro toxicity assays on islets and used in the isolation procedure to investigate whether they adversely affect islet isolation efficiency. The evaluations included islet yield, ADP/ATP, ATP/DNA, glucose stimulation test, and insulin/DNA assays. Islet viability cultured with PB contained medium was significantly lower than the other dyes. DG and IC appeared to be non-toxic to the islets. In isolation experiments, the islet yield in the DG group was considerably lower than that in the Control group, suggesting that DG might inhibit enzyme activity. The present study demonstrates that IC could be a promising candidate for an effective dye to detect damaged pancreatic tissues without affecting the enzyme activity and islet quality.


Assuntos
Corantes/farmacologia , Índigo Carmim/farmacologia , Ilhotas Pancreáticas/patologia , Pâncreas/efeitos dos fármacos , Fenóis/farmacologia , Pirróis/farmacologia , Difosfato de Adenosina/química , Trifosfato de Adenosina/química , Animais , DNA/efeitos dos fármacos , Glucose/química , Humanos , Insulina/química , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/ultraestrutura , Pâncreas/patologia , Pâncreas/ultraestrutura , Suínos
4.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209772

RESUMO

Due to the limited number of organ donors, 3D printing of organs is a promising technique. Tissue engineering is increasingly using xenogeneic material for this purpose. This study was aimed at assessing the safety of decellularized porcine pancreas, together with the analysis of the risk of an undesirable immune response. We tested eight variants of the decellularization process. We determined the following impacts: rinsing agents (PBS/NH3·H2O), temperature conditions (4 °C/24 °C), and the grinding method of native material (ground/cut). To assess the quality of the extracellular matrix after the completed decellularization process, analyses of the following were performed: DNA concentration, fat content, microscopic evaluation, proteolysis, material cytotoxicity, and most importantly, the Triton X-100 content. Our analyses showed that we obtained a product with an extremely low detergent content with negligible residual DNA content. The obtained results confirmed the performed histological and immuno-fluorescence staining. Moreover, the TEM microscopic analysis proved that the correct collagen structure was preserved after the decellularization process. Based on the obtained results, we chose the most favorable variant in terms of quality and biology. The method we chose is an effective and safe method that gives a chance for the development of transplant and regenerative medicine.


Assuntos
Matriz Extracelular/fisiologia , Pâncreas/ultraestrutura , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Bioimpressão/métodos , Células Cultivadas , Detergentes/química , Detergentes/farmacologia , Matriz Extracelular/química , Fibroblastos/citologia , Fibroblastos/fisiologia , Teste de Materiais , Camundongos , Octoxinol/química , Octoxinol/farmacologia , Pâncreas/citologia , Pós/química , Impressão Tridimensional , Proteômica , Controle de Qualidade , Suínos , Engenharia Tecidual/normas , Tecidos Suporte/química , Tecidos Suporte/normas
5.
PLoS One ; 16(5): e0252287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34043732

RESUMO

In recent years, the rapid development of deep neural networks has made great progress in automatic organ segmentation from abdominal CT scans. However, automatic segmentation for small organs (e.g., the pancreas) is still a challenging task. As an inconspicuous and small organ in the abdomen, the pancreas has a high degree of anatomical variability and is indistinguishable from the surrounding organs and tissues, which usually leads to a very vague boundary. Therefore, the accuracy of pancreatic segmentation is sometimes below satisfaction. In this paper, we propose a 2.5D U-net with an attention mechanism. The proposed network includes 2D convolutional layers and 3D convolutional layers, which means that it requires less computational resources than 3D segmentation models while it can capture more spatial information along the third dimension than 2D segmentation models. Then We use a cascaded framework to increase the accuracy of segmentation results. We evaluate our network on the NIH pancreas dataset and measure the segmentation accuracy by the Dice similarity coefficient (DSC). Experimental results demonstrate a better performance compared with state-of-the-art methods.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Pâncreas/ultraestrutura , Tomografia Computadorizada por Raios X/métodos , Humanos
6.
Inflammation ; 44(3): 1175-1183, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33417178

RESUMO

Acute pancreatitis (AP) is an inflammatory reaction of pancreatic tissue self-digestion, edema, hemorrhage, and even necrosis after the activation of pancreatic enzymes in the pancreas caused by a variety of etiologies. This study was aimed to explore the functions and mechanism of Wip1 in AP. Twenty male SD rats were randomly assigned into 2 groups (control group: saline treatment; AP group: cerulein treatment). And cerulein-treated AR42J cells were conducted as AP model in vitro. The levels of amylase were detected by using the Beckman biochemical analyzer. The levels of IFNß and TNFα were analyzed by ELISA. The autophagosomes were observed by transmission electron microscopy. The Wip1-specific shRNAs were transfected to AR42J cells to silence the expression of Wip1. The levels of Wip1 were measured by qRT-PCR and Western blot. The levels of STING/TBK1/IRF3 and LC3 were measured by Western blot. The AP model was successfully constructed by cerulein administration. Wip1 was notably upregulated in AP models. Autophagy and STING pathway activation were involved in the development of AP. Wip1 inhibition counteracts the promotion effect on inflammatory response induced by cerulein in AR42J Cells. Wip1 inhibition inhibited the activity of the STING/TBK1/IRF3 and reduced LC3 levels in AP. This study preliminarily explored that Wip1 could regulate autophagy and participate in the development of AP through the STING/TBK1/IRF3 signaling pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Autofagia , Fator Regulador 3 de Interferon/metabolismo , Proteínas de Membrana/metabolismo , Pâncreas/enzimologia , Pancreatite/enzimologia , Proteína Fosfatase 2C/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Linhagem Celular , Ceruletídeo , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Masculino , Pâncreas/ultraestrutura , Pancreatite/induzido quimicamente , Pancreatite/patologia , Pancreatite/prevenção & controle , Proteína Fosfatase 2C/genética , Ratos Sprague-Dawley , Transdução de Sinais , Regulação para Cima
7.
Inflammation ; 44(3): 999-1013, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33417179

RESUMO

Acute pancreatitis (AP) is an inflammatory, complicated pancreatic disease, carrying significant morbidity and mortality. However, the molecular and cellular mechanisms involved in AP pathogenesis remain to be elucidated. Here, we explore the role of FOXF1 adjacent non-coding developmental regulatory RNA (FENDRR) in AP progression. Caerulein with or without LPS- induced or taurolithocholic acid 3-sulfate (TLC-S)-induced AP mouse models and cell models were performed for the validation of FENDRR expression in vivo and in vitro, respectively. Histopathological examinations of pancreatic tissues were performed to evaluate the severity of AP. Transmission electron microscopy was utilized to visualize the autophagic vacuoles. siRNA specifically targeting FENDRR was further applied. Flow cytometry was employed to assess cell apoptosis. ELISA, immunoflureoscence, and western blotting analysis were also performed to determine the levels of inflammatory cytokines and autophagy activity. RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays were carried out to reveal the epigenetic regulation of FENDRR on ATG7. Additionally, silencing FENDRR was also verified in AP mouse models. Higher FENDRR and impaired autophagy were displayed in both AP mouse models and cell models. FENDRR knockdown dramatically attenuated caerulein- or TLC-S-induced AR42J cells apoptosis and autophagy suppression. Further mechanistic experiments implied that the action of FENDRR is moderately attributable to its repression of ATG7 via direct interaction with the epigenetic repressor PRC2. Moreover, the silencing of FENDRR significantly induced the promotion of ATG7, thus alleviating the development of AP in vivo. Our study highlights FENDRR as a novel target that may contribute to AP progression, suggesting a therapeutic target for AP treatment.


Assuntos
Proteína 7 Relacionada à Autofagia/metabolismo , Autofagia , Epigênese Genética , Pâncreas/metabolismo , Pancreatite/metabolismo , Complexo Repressor Polycomb 2/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Proteína 7 Relacionada à Autofagia/genética , Linhagem Celular , Ceruletídeo , Citocinas/metabolismo , Modelos Animais de Doenças , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos C57BL , Pâncreas/ultraestrutura , Pancreatite/induzido quimicamente , Pancreatite/genética , Pancreatite/patologia , Complexo Repressor Polycomb 2/genética , RNA Longo não Codificante/genética , Transdução de Sinais
8.
Sci Rep ; 11(1): 1944, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479301

RESUMO

The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is attributed to the highly fibrotic stroma and complex multi-cellular microenvironment that is difficult to fully recapitulate in pre-clinical models. To fast-track translation of therapies and to inform personalised medicine, we aimed to develop a whole-tissue ex vivo explant model that maintains viability, 3D multicellular architecture, and microenvironmental cues of human pancreatic tumours. Patient-derived surgically-resected PDAC tissue was cut into 1-2 mm explants and cultured on gelatin sponges for 12 days. Immunohistochemistry revealed that human PDAC explants were viable for 12 days and maintained their original tumour, stromal and extracellular matrix architecture. As proof-of-principle, human PDAC explants were treated with Abraxane and we observed different levels of response between patients. PDAC explants were also transfected with polymeric nanoparticles + Cy5-siRNA and we observed abundant cytoplasmic distribution of Cy5-siRNA throughout the PDAC explants. Overall, our novel model retains the 3D architecture of human PDAC and has advantages over standard organoids: presence of functional multi-cellular stroma and fibrosis, and no tissue manipulation, digestion, or artificial propagation of organoids. This provides unprecedented opportunity to study PDAC biology including tumour-stromal interactions and rapidly assess therapeutic response to drive personalised treatment.


Assuntos
Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Técnicas de Cultura de Células , Organoides/patologia , Adenocarcinoma/patologia , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Matriz Extracelular/patologia , Matriz Extracelular/ultraestrutura , Humanos , Organoides/ultraestrutura , Pâncreas/patologia , Pâncreas/ultraestrutura , Microambiente Tumoral/genética
9.
FEBS J ; 288(13): 4081-4097, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33403797

RESUMO

Nuclear protein 1 (NUPR1) is a stress response protein overexpressed upon cell injury in virtually all organs including the exocrine pancreas. Despite NUPR1's well-established role in the response to cell stress, the molecular and structural machineries triggered by NUPR1 activation remain largely debated. In this study, we uncover a new role for NUPR1, participating in the unfolded protein response (UPR) and the integrated stress response. Biochemical results and ultrastructural morphological observations revealed alterations in the UPR of acinar cells of germline-deleted NUPR1 murine models, consistent with the inability to restore general protein synthesis after stress induction. Bioinformatic analysis of NUPR1-interacting partners showed significant enrichment in translation initiation factors, including eukaryotic initiation factor (eIF) 2α. Co-immunoprecipitation and proximity ligation assays confirmed the interaction between NUPR1 and eIF2α and its phosphorylated form (p-eIF2α). Furthermore, our data suggest loss of NUPR1 in cells results in maintained eIF2α phosphorylation and evaluation of nascent proteins by click chemistry revealed that NUPR1-depleted PANC-1 cells displayed a slower poststress protein synthesis recovery when compared to wild-type. Combined, these data propose a novel role for NUPR1 in the integrated stress response pathway, at least partially through promoting efficient PERK branch activity and resolution through a unique interaction with eIF2α.


Assuntos
Proteínas de Ligação a DNA/genética , Estresse do Retículo Endoplasmático/genética , Fator de Iniciação 2 em Eucariotos/genética , Regulação da Expressão Gênica , Proteínas de Neoplasias/genética , Pâncreas/metabolismo , Resposta a Proteínas não Dobradas/genética , Células Acinares/metabolismo , Células Acinares/ultraestrutura , Animais , Western Blotting , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Proteínas de Neoplasias/metabolismo , Pâncreas/citologia , Pâncreas/ultraestrutura , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Nat Protoc ; 16(1): 239-262, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33247285

RESUMO

Advances in light-sheet and confocal microscopy now allow imaging of cleared large biological tissue samples and enable the 3D appreciation of cell and protein localization in their native organ environment. However, the sample preparations for such imaging are often onerous, and their capability for antigen detection is limited. Here, we describe FLASH (fast light-microscopic analysis of antibody-stained whole organs), a simple, rapid, fully customizable technique for molecular phenotyping of intact tissue volumes. FLASH utilizes non-degradative epitope recovery and membrane solubilization to enable the detection of a multitude of membranous, cytoplasmic and nuclear antigens in whole mouse organs and embryos, human biopsies, organoids and Drosophila. Retrieval and immunolabeling of epithelial markers, an obstacle for previous clearing techniques, can be achieved with FLASH. Upon volumetric imaging, FLASH-processed samples preserve their architecture and integrity and can be paraffin-embedded for subsequent histopathological analysis. The technique can be performed by scientists trained in light microscopy and yields results in <1 week.


Assuntos
Antígenos/análise , Imunofluorescência/métodos , Imageamento Tridimensional/métodos , Microscopia Confocal/métodos , Animais , Drosophila , Epitopos/análise , Feminino , Humanos , Rim/ultraestrutura , Aparelho Lacrimal/ultraestrutura , Fígado/ultraestrutura , Pulmão/ultraestrutura , Masculino , Glândulas Mamárias Humanas/ultraestrutura , Camundongos , Organoides/ultraestrutura , Pâncreas/ultraestrutura , Estômago/ultraestrutura
11.
Sci Rep ; 10(1): 17572, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067578

RESUMO

Although gold-standard histological assessment is subjective it remains central to diagnosis and clinical trial protocols and is crucial for the evaluation of any preclinical disease model. Objectivity and reproducibility are enhanced by quantitative analysis of histological images but current methods require application-specific algorithm training and fail to extract understanding from the histological context of observable features. We reinterpret histopathological images as disease landscapes to describe a generalisable framework defining topographic relationships in tissue using geoscience approaches. The framework requires no user-dependent training to operate on all image datasets in a classifier-agnostic manner but is adaptable and scalable, able to quantify occult abnormalities, derive mechanistic insights, and define a new feature class for machine-learning diagnostic classification. We demonstrate application to inflammatory, fibrotic and neoplastic disease in multiple organs, including the detection and quantification of occult lobular enlargement in the liver secondary to hilar obstruction. We anticipate this approach will provide a robust class of histological data for trial stratification or endpoints, provide quantitative endorsement of experimental models of disease, and could be incorporated within advanced approaches to clinical diagnostic pathology.


Assuntos
Ciências da Terra/métodos , Técnicas Histológicas , Processamento de Imagem Assistida por Computador/métodos , Patologia Clínica/métodos , Animais , Modelos Animais de Doenças , Humanos , Rim/ultraestrutura , Fígado/ultraestrutura , Hepatopatias/patologia , Aprendizado de Máquina , Camundongos , Especificidade de Órgãos , Pâncreas/ultraestrutura , Reprodutibilidade dos Testes , Software , Doenças da Glândula Tireoide/patologia , Glândula Tireoide/ultraestrutura
12.
J Vis Exp ; (163)2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32955501

RESUMO

Islet transplantation (ITx) has the potential to become the standard of care in beta cell replacement medicine but its results remain inferior to those obtained with whole pancreas transplantation. The protocols currently used for human islet isolation are under scrutiny because they are based on the enzymatic digestion of the organ, whereby the pancreas is demolished, its connections to the body are lost and islets are irreversibly damaged. Islet damage is characterized by critical factors such as the destruction of the extracellular matrix (ECM), which represents the 3D framework of the islet niche and whose loss is incompatible with islet euphysiology. Researchers are proposing the use of ECM-based scaffolds derived from the mammalian pancreas to address this problem and ultimately improve islet viability, function, and lifespan. Currently available methods to obtain such scaffolds are harsh because they are largely detergent based. Thus, we propose a new, detergent-free method that creates less ECM damage and can preserve critical components of pancreatic ECM. The results show that the newly developed decellularization protocol allowed the achievement of complete DNA clearance while the ECM components were retained. The ECM obtained was tested for cytotoxicity and encapsulated with human pancreatic islets which showed a positive cellular behavior with insulin secretion when stimulated with glucose challenge. Collectively, we propose a new method for the decellularization of the human pancreas without the use of conventional ionic and non-ionic chemical detergents. This protocol and the ECM obtained with it could be of use for both in vitro and in vivo applications.


Assuntos
Matriz Extracelular/química , Pâncreas/ultraestrutura , Engenharia Tecidual/métodos , Tecidos Suporte/química , Humanos , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Pâncreas/citologia , Pâncreas/metabolismo , Solubilidade
13.
Biochem Biophys Res Commun ; 529(2): 238-242, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32703417

RESUMO

High-speed imaging of living specimen was performed using two-photon microscopy equipped with a spinning-disk scanning unit. Typically, a high-peak-power laser light source is needed to simultaneously induce two-photon excitation processes at several hundred focal points, generating the limitations of excitable fluorophores. Therefore, a high-peak-power neodymium-based 918-nm laser light source was used for intravital imaging of the most popular fluorophores, green fluorescent proteins. As a result, the proposed system obtained approximately 30 times brighter fluorescent signal than that obtained using a conventional mode-locked titanium:sapphire laser light source. Furthermore, the system visualized four-dimensional (xyz-t) calcium responses of pancreatic acinar cells agonist stimulations in the living G-CaMP7-expressing mouse with 60 million µm3 volume.


Assuntos
Corantes Fluorescentes/análise , Proteínas de Fluorescência Verde/análise , Microscopia de Fluorescência/instrumentação , Células Acinares/ultraestrutura , Animais , Desenho de Equipamento , Lasers , Camundongos , Pâncreas/ultraestrutura , Pele/ultraestrutura
14.
Int J Mol Sci ; 21(6)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192184

RESUMO

The existence of telocytes (TCs) has not yet been established in the pancreases of aquatic reptiles. Here, we report TCs in the exocrine pancreas of Pelodiscus sinensis using transmission electron microscope (TEM), immunohistochemistry (IHC), and immunofluorescence (IF) techniques. TCs surrounded the acini and ducts of the connective tissue of the exocrine pancreas and between lobules and gland cells. The cells were located preferably close to the blood vessels, interlobular ducts, and nerve fibers. Ultrastructurally, TCs exhibited small and large bodies with thick and thin portions, podoms, and podomers, and prolongations that form dichotomous branching with hetero-cellular and homo-cellular junctions. The podom (thick) portions showed caveolae, mitochondria, rough endoplasmic reticulum, and vesicles. The nucleus carries heterochromatin and is irregular in shape. The shape of TCs depends on the number of telopodes (Tps) bearing long, short, spindle, triangular, and "beads on a string" shapes with twisted, tortuous prolongations and ramifications. Shed extracellular vesicles and exosomes were found frequently released from projections and Tps within connective tissue in the vicinity of the acini and collagen fibers. IHC and IF results showed CD34+, α-SMA+, and vimentin+, long and triangle-shaped TCs, consistent with the TEM findings. The presence of shaded vesicles from TCs might implicate their possible role in immune surveillance, tissue regeneration as well as regulatory functions in the reptilian pancreas.


Assuntos
Comunicação Celular , Pâncreas/citologia , Pâncreas/ultraestrutura , Telócitos/fisiologia , Telócitos/ultraestrutura , Tartarugas , Animais , Biomarcadores , Exossomos/metabolismo , Imunofluorescência , Imuno-Histoquímica , Pâncreas/fisiologia
15.
Anat Histol Embryol ; 49(3): 345-350, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32017197

RESUMO

The aim of this research work was to study the histological structure of the pancreatic acini by transmission electron microscope in two avian species, duck and pigeon. The specimens were collected and processed for electron microscopic study. The results showed that the acini of the two avian species were two types; the first one was an electron dense and the second one an electron lucent. The light acinar cells were larger in size than the dark cells. These cells contained centrally located ovoid nuclei with prominent nucleoli and abundant euchromatin. The cytoplasm was electron lucent, with many rough endoplasmic reticulum, polymorphic mitochondria. Numerous zymogen granules were distributed in the basal part and around the nucleus, so these cells considered active cells. The dark acinar cells were characterized by an electron dense cytoplasm. The most prominent cell organelle in these cells were the zymogen granules that appeared in different sizes while other organelles as mitochondria, and rough endoplasmic reticulum were inconspicuous or few, so these cells were considered as inactive cells. The nucleus with indented nuclear membrane located centrally with prominent nucleoli and abundant heterochromatin. Prominent intercellular spaces between the individual acinar cells, as well as well-developed basement membrane separating the electron dense cells and the lumen contained the secretion between acinar cells. It could be concluded that the acinar cells in ducks and pigeons were divided into two types, that is, light and dark acinar cells which mainly attributed to the activity of these cells.


Assuntos
Células Acinares/ultraestrutura , Columbidae , Patos , Pâncreas/ultraestrutura , Animais , Columbidae/anatomia & histologia , Patos/anatomia & histologia , Microscopia Eletrônica/veterinária
16.
Ultrastruct Pathol ; 44(1): 61-70, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31888398

RESUMO

An adequate experimental model is important to understand pathophysiological processes ongoing in the pancreas with diabetes mellitus. Our study was aimed to describe early ultra- and microstructural changes in the rat pancreas in 12-48 h after alloxan administration in a dose of 180 mg/kg. A histopathological examination of the endocrine pancreas revealed the loss of borders between endocrine cells, granular dystrophy and degranulation, sings of necrosis in central cells of the Langerhans islets and apoptosis of their peripheral ones manifested as DNA fragmentation and an increased expression of apoptosis markers. There was a gradual increase of a Langerhans islet area, a decreased percentage of insulin+ cells and an increased one of glucagon+ cells, as well as the presence of proliferating islet cells were found. Structural changes of the exocrine pancreas included fatty degeneration, signs of exocrine cell mitochondrial damage, increased acini, which are located mainly around the Langerhans islets, as well as perivascular edema and leukocytic infiltration. Described ultra- and microstructural alterations suggest a significant contribution of apoptosis to death of endocrine cells exposed to alloxan. Coexisting damage of the exocrine pancreas with its stroma involvement is for the first time described.


Assuntos
Diabetes Mellitus Experimental/patologia , Pâncreas/patologia , Pâncreas/ultraestrutura , Animais , Masculino , Microscopia Eletrônica de Transmissão , Ratos , Ratos Wistar
17.
Biochem Biophys Res Commun ; 522(2): 518-524, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31784085

RESUMO

Acute pancreatitis (AP) is one of the leading causes of hospital admission for gastrointestinal disorders. Although lipid peroxides are produced in AP, it is unknown if targeting lipid peroxides prevents AP. This study aimed to investigate the role of mitochondrial aldehyde dehydrogenase 2 (ALDH2), a critical enzyme for lipid peroxide degradation, in AP and the possible underlying mechanisms. Cerulein was used to induce AP in C57BL/6 J male mice and pancreatic acinar cells were used to elucidate underlying mechanisms in vitro. Pancreatic enzymes in the serum, lipid peroxidation products malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), and Bcl-2, Bax and cleaved caspase-3 were measured. ALDH2 activation with a small-molecule activator, Alda-1, reduced the levels of the pancreatic enzymes in the serum and the lipid peroxidation products MDA and 4-HNE. In addition, Alda-1 decreased Bax and cleaved caspase-3 expression and increased Bcl-2 expression in vivo and in vitro. In conclusion, ALDH2 activation by Alda-1 has a protective effect in cerulein-induced AP by mitigating apoptosis in pancreatic acinar cells by alleviating lipid peroxidation.


Assuntos
Aldeído-Desidrogenase Mitocondrial/metabolismo , Pancreatite/tratamento farmacológico , Pancreatite/patologia , Índice de Gravidade de Doença , Aldeídos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Benzamidas/administração & dosagem , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Benzodioxóis/administração & dosagem , Benzodioxóis/farmacologia , Benzodioxóis/uso terapêutico , Linhagem Celular , Ceruletídeo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos C57BL , Pâncreas/efeitos dos fármacos , Pâncreas/lesões , Pâncreas/patologia , Pâncreas/ultraestrutura , Pancreatite/induzido quimicamente , Pancreatite/enzimologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Bibliotecas de Moléculas Pequenas/farmacologia
19.
Mol Biol Rep ; 46(5): 4787-4797, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31228042

RESUMO

Pancreatic ß cell damage is one of the crucial factors responsible for the development of type 2 diabetes mellitus (T2DM). Previous studies have suggested that puerarin (PR) could regulate the activities of the mitochondrial respiratory chain complex in diabetic nephropathy (DN); however, whether PR can inhibit pancreatic ß-cell apoptosis in T2DM remains to be elucidated. In the present study, T2DM mice induced by high-fat diet and streptozotocin (STZ) injection were used as a working model to investigate the mechanism of PR on pancreatic ß cell apoptosis. The results showed that PR decreased the serum fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG) and low-density lipoprotein (LDL) levels but significantly increased the fasting blood insulin (FINS) and high-density lipoprotein (HDL) levels. Furthermore, decreased caspase-3, 8, 9 and apoptosis-inducing factor (AIF) proteins in the pancreas were detected by Western blot analysis. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) staining demonstrated that the pancreatic ß cell apoptosis was inhibited by PR. Furthermore, PR improved the histopathological changes in pancreatic tissue in T2DM mice. Collectively, the data show that PR can protect the ß cells from apoptotic death in a mouse model of T2DM through regulating the expression of apoptosis-related protein-AIF and caspase family proteins.


Assuntos
Fator de Indução de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Hipoglicemiantes/farmacologia , Isoflavonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/genética , Biomarcadores , Glicemia , Caspases/genética , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Jejum , Expressão Gênica , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Isoflavonas/química , Isoflavonas/uso terapêutico , Lipídeos/sangue , Camundongos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Pâncreas/ultraestrutura
20.
Folia Morphol (Warsz) ; 78(4): 762-772, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30816553

RESUMO

BACKGROUND: Hyperlipidaemia is a risk factor for the development and progression of atherosclerosis and is linked to various diseases. This study was done to evaluate the possible protective effects of virgin olive oil and Nigella sativa seeds on the biochemical and histopathological changes which occurred in the pancreas of the rats. The study lasted 8 weeks and included 24 albino rats that were divided into four groups (6 rats each); Group I - control group, fed with normal standard diet, Group II - fed with high fat diet (HFD), Group III - fed with HFD and virgin olive oil, Group IV - fed with HFD and Nigella sativa seeds powder. MATERIALS AND METHODS: After finishing the experiment, blood samples were collected and assessed for the lipid profile, fasting blood glucose, pancreatic amylase and insulin levels. Then, the rats were sacrificed and the pancreata were extracted and slices of them were processed for histological examination using haematoxylin stain and Masson's trichrome stain. Small fragments from the tail of the pancreata were extracted and processed for electron microscopic examination. The statistical analysis of the data using the appropriate statistical tests was also conducted. RESULTS: In the present study, the serum lipid profile in hyperlipidaemic rats was ameliorated in rats fed on high fat diet with virgin olive oil or Nigella sativa seed powder, which was reflected by a significant decrease in total cholesterol, low-density lipoprotein-cholesterol and triglycerides. Moreover, Nigella sativa decreased high-density lipoprotein (HDL), while virgin olive oil significantly increased HDL. Also a significant decrease in the serum levels of blood glucose and amylase and a significant increase in insulin levels were present in these groups. The histological and ultrastructural results revealed regeneration of the exocrine and endocrine parts of the pancreatic tissues from the hyperlipidaemic rats fed with virgin olive oil or Nigella sativa seeds. CONCLUSIONS: In this study, the biochemical results were paralleled to the histological and ultrastructural results; therefore, it could be concluded that virgin olive oil and Nigella sativa seeds had antihyperlipidaemic and hypoglycaemic effects and they could protect the pancreas from hyperlipidaemia-induced injury. Daily consumption of virgin olive oil and Nigella sativa seeds in the diet is highly recommended.


Assuntos
Hiperlipidemias/patologia , Nigella sativa/química , Azeite de Oliva/farmacologia , Pâncreas/patologia , Substâncias Protetoras/farmacologia , Sementes/química , Animais , Glicemia/metabolismo , Hiperlipidemias/sangue , Lipídeos/sangue , Pâncreas/efeitos dos fármacos , Pâncreas/ultraestrutura , Ratos
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