RESUMEN
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.
Asunto(s)
Colorantes/farmacología , Carmin de Índigo/farmacología , Islotes Pancreáticos/patología , Páncreas/efectos de los fármacos , Fenoles/farmacología , Pirroles/farmacología , Adenosina Difosfato/química , Adenosina Trifosfato/química , Animales , ADN/efectos de los fármacos , Glucosa/química , Humanos , Insulina/química , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/ultraestructura , Páncreas/patología , Páncreas/ultraestructura , PorcinosRESUMEN
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.
Asunto(s)
Proteínas Portadoras/genética , Cilios/metabolismo , Páncreas Exocrino/metabolismo , Páncreas/metabolismo , Pancreatitis/genética , Células Acinares/metabolismo , Animales , Atrofia , Proteínas Portadoras/metabolismo , Ciliopatías/genética , Ciliopatías/metabolismo , Exocitosis/genética , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Electrónica de Transmisión , Páncreas/patología , Páncreas/ultraestructura , Páncreas Exocrino/patología , Pancreatitis/metabolismo , Vesículas Secretoras/metabolismoRESUMEN
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.
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Matriz Extracelular/fisiología , Páncreas/ultraestructura , Ingeniería de Tejidos/métodos , Andamios del Tejido , Animales , Bioimpresión/métodos , Células Cultivadas , Detergentes/química , Detergentes/farmacología , Matriz Extracelular/química , Fibroblastos/citología , Fibroblastos/fisiología , Ensayo de Materiales , Ratones , Octoxinol/química , Octoxinol/farmacología , Páncreas/citología , Polvos/química , Impresión Tridimensional , Proteómica , Control de Calidad , Porcinos , Ingeniería de Tejidos/normas , Andamios del Tejido/química , Andamios del Tejido/normasRESUMEN
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.
Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Páncreas/ultraestructura , Tomografía Computarizada por Rayos X/métodos , HumanosRESUMEN
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.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Autofagia , Factor 3 Regulador del Interferón/metabolismo , Proteínas de la Membrana/metabolismo , Páncreas/enzimología , Pancreatitis/enzimología , Proteína Fosfatasa 2C/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Línea Celular , Ceruletida , Citocinas/metabolismo , Modelos Animales de Enfermedad , Mediadores de Inflamación/metabolismo , Masculino , Páncreas/ultraestructura , Pancreatitis/inducido químicamente , Pancreatitis/patología , Pancreatitis/prevención & control , Proteína Fosfatasa 2C/genética , Ratas Sprague-Dawley , Transducción de Señal , Regulación hacia ArribaRESUMEN
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.
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Proteína 7 Relacionada con la Autofagia/metabolismo , Autofagia , Epigénesis Genética , Páncreas/metabolismo , Pancreatitis/metabolismo , Complejo Represivo Polycomb 2/metabolismo , ARN Largo no Codificante/metabolismo , Animales , Proteína 7 Relacionada con la Autofagia/genética , Línea Celular , Ceruletida , Citocinas/metabolismo , Modelos Animales de Enfermedad , Mediadores de Inflamación/metabolismo , Lipopolisacáridos , Masculino , Ratones Endogámicos C57BL , Páncreas/ultraestructura , Pancreatitis/inducido químicamente , Pancreatitis/genética , Pancreatitis/patología , Complejo Represivo Polycomb 2/genética , ARN Largo no Codificante/genética , Transducción de SeñalRESUMEN
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.
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Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Técnicas de Cultivo de Célula , Organoides/patología , Adenocarcinoma/patología , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Matriz Extracelular/patología , Matriz Extracelular/ultraestructura , Humanos , Organoides/ultraestructura , Páncreas/patología , Páncreas/ultraestructura , Microambiente Tumoral/genéticaRESUMEN
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.
Asunto(s)
Proteínas de Unión al ADN/genética , Estrés del Retículo Endoplásmico/genética , Factor 2 Eucariótico de Iniciación/genética , Regulación de la Expresión Génica , Proteínas de Neoplasias/genética , Páncreas/metabolismo , Respuesta de Proteína Desplegada/genética , Células Acinares/metabolismo , Células Acinares/ultraestructura , Animales , Western Blotting , Línea Celular Tumoral , Proteínas de Unión al ADN/metabolismo , Factor 2 Eucariótico de Iniciación/metabolismo , Humanos , Ratones Noqueados , Microscopía Electrónica de Transmisión , Proteínas de Neoplasias/metabolismo , Páncreas/citología , Páncreas/ultraestructura , Unión Proteica , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
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.
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Antígenos/análisis , Técnica del Anticuerpo Fluorescente/métodos , Imagenología Tridimensional/métodos , Microscopía Confocal/métodos , Animales , Drosophila , Epítopos/análisis , Femenino , Humanos , Riñón/ultraestructura , Aparato Lagrimal/ultraestructura , Hígado/ultraestructura , Pulmón/ultraestructura , Masculino , Glándulas Mamarias Humanas/ultraestructura , Ratones , Organoides/ultraestructura , Páncreas/ultraestructura , Estómago/ultraestructuraRESUMEN
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.
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Ciencias de la Tierra/métodos , Técnicas Histológicas , Procesamiento de Imagen Asistido por Computador/métodos , Patología Clínica/métodos , Animales , Modelos Animales de Enfermedad , Humanos , Riñón/ultraestructura , Hígado/ultraestructura , Hepatopatías/patología , Aprendizaje Automático , Ratones , Especificidad de Órganos , Páncreas/ultraestructura , Reproducibilidad de los Resultados , Programas Informáticos , Enfermedades de la Tiroides/patología , Glándula Tiroides/ultraestructuraRESUMEN
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.
Asunto(s)
Matriz Extracelular/química , Páncreas/ultraestructura , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Humanos , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Páncreas/citología , Páncreas/metabolismo , SolubilidadRESUMEN
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.
Asunto(s)
Colorantes Fluorescentes/análisis , Proteínas Fluorescentes Verdes/análisis , Microscopía Fluorescente/instrumentación , Células Acinares/ultraestructura , Animales , Diseño de Equipo , Rayos Láser , Ratones , Páncreas/ultraestructura , Piel/ultraestructuraRESUMEN
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.
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Comunicación Celular , Páncreas/citología , Páncreas/ultraestructura , Telocitos/fisiología , Telocitos/ultraestructura , Tortugas , Animales , Biomarcadores , Exosomas/metabolismo , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Páncreas/fisiologíaRESUMEN
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.
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Células Acinares/ultraestructura , Columbidae , Patos , Páncreas/ultraestructura , Animales , Columbidae/anatomía & histología , Patos/anatomía & histología , Microscopía Electrónica/veterinariaRESUMEN
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.
Asunto(s)
Diabetes Mellitus Experimental/patología , Páncreas/patología , Páncreas/ultraestructura , Animales , Masculino , Microscopía Electrónica de Transmisión , Ratas , Ratas WistarRESUMEN
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.
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Aldehído Deshidrogenasa Mitocondrial/metabolismo , Pancreatitis/tratamiento farmacológico , Pancreatitis/patología , Índice de Severidad de la Enfermedad , Aldehídos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Benzamidas/administración & dosificación , Benzamidas/farmacología , Benzamidas/uso terapéutico , Benzodioxoles/administración & dosificación , Benzodioxoles/farmacología , Benzodioxoles/uso terapéutico , Línea Celular , Ceruletida , Peroxidación de Lípido/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Ratones Endogámicos C57BL , Páncreas/efectos de los fármacos , Páncreas/lesiones , Páncreas/patología , Páncreas/ultraestructura , Pancreatitis/inducido químicamente , Pancreatitis/enzimología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Bibliotecas de Moléculas Pequeñas/farmacologíaAsunto(s)
Células Acinares/efectos de los fármacos , Autofagia/efectos de los fármacos , Pancreatitis/patología , Puromicina/farmacología , Vacuolas/ultraestructura , Células Acinares/patología , Células Acinares/ultraestructura , Animales , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/farmacología , Humanos , Masculino , Microscopía Electrónica de Transmisión , Páncreas/efectos de los fármacos , Páncreas/patología , Páncreas/ultraestructura , Puromicina/administración & dosificación , Ratas WistarRESUMEN
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.
Asunto(s)
Factor Inductor de la Apoptosis/metabolismo , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Hipoglucemiantes/farmacología , Isoflavonas/farmacología , Transducción de Señal/efectos de los fármacos , Animales , Apoptosis/genética , Biomarcadores , Glucemia , Caspasas/genética , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Ayuno , Expresión Génica , Hipoglucemiantes/química , Hipoglucemiantes/uso terapéutico , Insulina/sangre , Isoflavonas/química , Isoflavonas/uso terapéutico , Lípidos/sangre , Ratones , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Páncreas/patología , Páncreas/ultraestructuraRESUMEN
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.
Asunto(s)
Hiperlipidemias/patología , Nigella sativa/química , Aceite de Oliva/farmacología , Páncreas/patología , Sustancias Protectoras/farmacología , Semillas/química , Animales , Glucemia/metabolismo , Hiperlipidemias/sangre , Lípidos/sangre , Páncreas/efectos de los fármacos , Páncreas/ultraestructura , RatasRESUMEN
OBJECTIVE: We aim to investigate whether C21, a selective angiotensin type 2 receptor agonist, can exert protective effects on pancreatic ß-cells through activation of antiapoptosis and autophagy. METHODS: The high-fat diet-induced obese rats (HFDs) were under C21 treatment for 4 weeks. RESULTS: C21 treatment decreased the fasting glucose levels and improved ß-cell insulin secretory function in the HFD group. Hematoxylin and eosin staining and electron microscopy indicated that the islet morphology was improved in the C21-treated obese rats, which was associated with increased levels of the key transcription factor PDX1, glucose sensing, and uptaking protein GCK and GLUT2, respectively. C21 treatment exerted antiapoptotic effects through decreasing the levels of apoptotic marker Caspase-3 while increasing the levels of antiapoptotic markers AKT, p-AKT, and BCL2. C21 treatment also induced autophagosome formation in the mitochondria of the ß-cells in the HFD group accompanied by increased levels of autophagy markers, LC-3B and Beclin-1. CONCLUSIONS: The results suggested C21 treatment decreased the fasting glucose level and protected ß-cell function in the HFD-induced obese rat model, which in part through activation of antiapoptotic and autophagy processes. This study provided preclinical evidence for the utilization of C21 in the treatment of type 2 diabetes.