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1.
J Clin Invest ; 133(20)2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37843277

RESUMEN

Improving the management of metastasis in pancreatic neuroendocrine tumors (PanNETs) is critical, as nearly half of patients with PanNETs present with liver metastases, and this accounts for the majority of patient mortality. We identified angiopoietin-2 (ANGPT2) as one of the most upregulated angiogenic factors in RNA-Seq data from human PanNET liver metastases and found that higher ANGPT2 expression correlated with poor survival rates. Immunohistochemical staining revealed that ANGPT2 was localized to the endothelial cells of blood vessels in PanNET liver metastases. We observed an association between the upregulation of endothelial ANGPT2 and liver metastatic progression in both patients and transgenic mouse models of PanNETs. In human and mouse PanNET liver metastases, ANGPT2 upregulation coincided with poor T cell infiltration, indicative of an immunosuppressive tumor microenvironment. Notably, both pharmacologic inhibition and genetic deletion of ANGPT2 in PanNET mouse models slowed the growth of PanNET liver metastases. Furthermore, pharmacologic inhibition of ANGPT2 promoted T cell infiltration and activation in liver metastases, improving the survival of mice with metastatic PanNETs. These changes were accompanied by reduced plasma leakage and improved vascular integrity in metastases. Together, these findings suggest that ANGPT2 blockade may be an effective strategy for promoting T cell infiltration and immunostimulatory reprogramming to reduce the growth of liver metastases in PanNETs.


Asunto(s)
Neoplasias Hepáticas , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Animales , Humanos , Ratones , Angiopoyetina 2/genética , Angiopoyetina 2/metabolismo , Células Endoteliales/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Ratones Transgénicos , Tumores Neuroendocrinos/tratamiento farmacológico , Tumores Neuroendocrinos/genética , Tumores Neuroendocrinos/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Linfocitos T/patología , Microambiente Tumoral
2.
Sensors (Basel) ; 23(15)2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37571619

RESUMEN

In recent years, both machine learning and computer vision have seen growth in the use of multi-label categorization. SMOTE is now being utilized in existing research for data balance, and SMOTE does not consider that nearby examples may be from different classes when producing synthetic samples. As a result, there can be more class overlap and more noise. To avoid this problem, this work presented an innovative technique called Adaptive Synthetic Data-Based Multi-label Classification (ASDMLC). Adaptive Synthetic (ADASYN) sampling is a sampling strategy for learning from unbalanced data sets. ADASYN weights minority class instances by learning difficulty. For hard-to-learn minority class cases, synthetic data are created. Their numerical variables are normalized with the help of the Min-Max technique to standardize the magnitude of each variable's impact on the outcomes. The values of the attribute in this work are changed to a new range, from 0 to 1, using the normalization approach. To raise the accuracy of multi-label classification, Velocity-Equalized Particle Swarm Optimization (VPSO) is utilized for feature selection. In the proposed approach, to overcome the premature convergence problem, standard PSO has been improved by equalizing the velocity with each dimension of the problem. To expose the inherent label dependencies, the multi-label classification ensemble of Adaptive Neuro-Fuzzy Inference System (ANFIS), Probabilistic Neural Network (PNN), and Clustering-Based Decision tree methods will be processed based on an averaging method. The following criteria, including precision, recall, accuracy, and error rate, are used to assess performance. The suggested model's multi-label classification accuracy is 90.88%, better than previous techniques, which is PCT, HOMER, and ML-Forest is 65.57%, 70.66%, and 82.29%, respectively.

3.
Environ Sci Pollut Res Int ; 30(60): 125197-125213, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37482589

RESUMEN

The prevalence of organic solid waste worldwide has turned into a problem that requires comprehensive treatment on all fronts. The amount of agricultural waste generated by agro-based industries has more than triplet. It not only pollutes the environment but also wastes a lot of beneficial biomass resources. These wastes may be utilized as a different option/source for the manufacturing of many goods, including biogas, biofertilizers, biofuel, mushrooms and tempeh as the primary ingredients in numerous industries. Utilizing agro-industrial wastes as good raw materials may provide cost reduction and lower environmental pollution levels. Agro-industrial wastes are converted into biofuels, enzymes, vitamin supplements, antioxidants, livestock feed, antibiotics, biofertilizers and other compounds via solid-state fermentation (SSF). By definition, SSF is a method used when there is little to no free water available. As a result, it permits the use of solid materials as biotransformation substrates. Through SSF methods, a variety of microorganisms are employed to produce these worthwhile things. SSFs are therefore reviewed and discussed along with their impact on the production of value-added items. This review will provide thorough essential details information on recycling and the use of agricultural waste.


Asunto(s)
Agricultura , Residuos Industriales , Fermentación , Residuos Industriales/análisis , Residuos Sólidos , Biocombustibles
4.
Cancer Res ; 83(12): 1968-1983, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37093870

RESUMEN

T-cell position in the tumor microenvironment determines the probability of target encounter and tumor killing. CD8+ T-cell exclusion from the tumor parenchyma is associated with poor response to immunotherapy, and yet the biology that underpins this distinct pattern remains unclear. Here we show that the vascular destabilizing factor angiopoietin-2 (ANGPT2) causes compromised vascular integrity in the tumor periphery, leading to impaired T-cell infiltration to the tumor core. The spatial regulation of ANGPT2 in whole tumor cross-sections was analyzed in conjunction with T-cell distribution, vascular integrity, and response to immunotherapy in syngeneic murine melanoma models. T-cell exclusion was associated with ANGPT2 upregulation and elevated vascular leakage at the periphery of human and murine melanomas. Both pharmacologic and genetic blockade of ANGPT2 promoted CD8+ T-cell infiltration into the tumor core, exerting antitumor effects. Importantly, the reversal of T-cell exclusion following ANGPT2 blockade not only enhanced response to anti-PD-1 immune checkpoint blockade therapy in immunogenic, therapy-responsive mouse melanomas, but it also rendered nonresponsive tumors susceptible to immunotherapy. Therapeutic response after ANGPT2 blockade, driven by improved CD8+ T-cell infiltration to the tumor core, coincided with spatial TIE2 signaling activation and increased vascular integrity at the tumor periphery where endothelial expression of adhesion molecules was reduced. These data highlight ANGPT2/TIE2 signaling as a key mediator of T-cell exclusion and a promising target to potentiate immune checkpoint blockade efficacy in melanoma. SIGNIFICANCE: ANGPT2 limits the efficacy of immunotherapy by inducing vascular destabilization at the tumor periphery to promote T-cell exclusion.


Asunto(s)
Angiopoyetina 2 , Melanoma , Humanos , Ratones , Animales , Angiopoyetina 2/genética , Inhibidores de Puntos de Control Inmunológico , Melanoma/terapia , Inmunoterapia , Linfocitos T CD8-positivos/metabolismo , Microambiente Tumoral
5.
Environ Sci Pollut Res Int ; 30(60): 125117-125137, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37115453

RESUMEN

The engine tests aimed to produce comparable data for fuel consumption, exhaust emissions, and thermal efficiency. The computational fluid dynamics (CFD) program FLUENT was used to simulate the combustion parameters of a direct injection diesel engine. In-cylinder turbulence is controlled using the RNG k-model. The model's conclusions are validated when the projected p-curve is compared to the observed p-curve. The thermal efficiency of the 50E50B blend (50% ethanol, 50% biofuel) is higher than the other blends as well as diesel. Diesel has lower brake thermal efficiency among the other fuel blends used. The 10E90B mix (10% ethanol, 90% biofuel) has a lower brake-specific fuel consumption (BSFC) than other blends but is slightly higher than diesel. The temperature of the exhaust gas rises for all mixtures as the brake power is increased. CO emissions from 50E50B are lower than diesel at low loads but slightly greater at heavy loads. According to the emission graphs, the 50E50B blend produces less HC than diesel. NOx emission rises with increasing load in the exhaust parameter for all mixes. A 50E50B biofuel-ethanol combination achieves the highest brake thermal efficiency, 33.59%. The BSFC for diesel is 0.254 kg/kW-hr at maximum load, while the BSFC for the 10E90B mix is 0.269 kg/kW-hr, higher than diesel. In comparison to diesel, BSFC has increased by 5.90%.


Asunto(s)
Biocombustibles , Gasolina , Etanol , Hidrodinámica , Emisiones de Vehículos , Monóxido de Carbono/análisis
6.
Sensors (Basel) ; 23(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36679684

RESUMEN

Recently, with the massive growth of IoT devices, the attack surfaces have also intensified. Thus, cybersecurity has become a critical component to protect organizational boundaries. In networks, Intrusion Detection Systems (IDSs) are employed to raise critical flags during network management. One aspect is malicious traffic identification, where zero-day attack detection is a critical problem of study. Current approaches are aligned towards deep learning (DL) methods for IDSs, but the success of the DL mechanism depends on the feature learning process, which is an open challenge. Thus, in this paper, the authors propose a technique which combines both CNN, and GRU, where different CNN-GRU combination sequences are presented to optimize the network parameters. In the simulation, the authors used the CICIDS-2017 benchmark dataset and used metrics such as precision, recall, False Positive Rate (FPR), True Positive Rate (TRP), and other aligned metrics. The results suggest a significant improvement, where many network attacks are detected with an accuracy of 98.73%, and an FPR rate of 0.075. We also performed a comparative analysis with other existing techniques, and the obtained results indicate the efficacy of the proposed IDS scheme in real cybersecurity setups.


Asunto(s)
Aprendizaje Profundo , Benchmarking , Seguridad Computacional , Simulación por Computador
7.
Sensors (Basel) ; 22(19)2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36236428

RESUMEN

DNA (Deoxyribonucleic Acid) Cryptography has revolutionized information security by combining rigorous biological and mathematical concepts to encode original information in terms of a DNA sequence. Such schemes are crucially dependent on corresponding DNA-based cryptographic keys. However, owing to the redundancy or observable patterns, some of the keys are rendered weak as they are prone to intrusions. This paper proposes a Genetic Algorithm inspired method to strengthen weak keys obtained from Random DNA-based Key Generators instead of completely discarding them. Fitness functions and the application of genetic operators have been chosen and modified to suit DNA cryptography fundamentals in contrast to fitness functions for traditional cryptographic schemes. The crossover and mutation rates are reducing with each new population as more keys are passing fitness tests and need not be strengthened. Moreover, with the increasing size of the initial key population, the key space is getting highly exhaustive and less prone to Brute Force attacks. The paper demonstrates that out of an initial 25 × 25 population of DNA Keys, 14 keys are rendered weak. Complete results and calculations of how each weak key can be strengthened by generating 4 new populations are illustrated. The analysis of the proposed scheme for different initial populations shows that a maximum of 8 new populations has to be generated to strengthen all 500 weak keys of a 500 × 500 initial population.


Asunto(s)
Algoritmos , Proyectos de Investigación , ADN/genética
8.
J Ambient Intell Humaniz Comput ; : 1-12, 2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-36117515

RESUMEN

In the year 2020, the word "pandemic" has become quite popular. A pandemic is a disease that spreads over a wide geographical region. The massive outbreak of coronavirus popularly known as COVID-19 has halted normal life worldwide. On 11th March 2020, the World Health Organization (WHO) quoted the COVID-19 outbreak as a "Pandemic". The outbreak pattern differs widely across the globe based on the findings discovered so far; however, fever is a common and easily detectable symptom of COVID-19 and the new COVID strain. After the virus outbreak, thermal scanning is done using infrared thermometers in most public places to detect infected persons. It is time-consuming to track the body temperature of each person. Besides, close contact with infected persons can spread the virus from the infected persons to the individual performing the screening or vice-versa. In this research, we propose a device architecture capable of automatically detecting the coronavirus or new COVID strain from thermal images; the proposed architecture comprises a smart mask equipped with a thermal imaging system, which reduces human interactions. The thermal camera technology is integrated with the smart mask powered by the Internet of Things (IoT) to proactively monitor the screening procedure and obtain data based on real-time findings. Besides, the proposed system is fitted with facial recognition technology; therefore, it can also display personal information. It will automatically measure the temperature of each person who came into close contact with the infected humans or humans in public spaces, such as markets or offices. The new design is very useful in healthcare and could offer a solution to preventing the growth of the coronavirus. The presented work hasa key focus on the integration of advanced algorithms for the predictive analytics of parameters required for in-depth evaluations. The proposed work and the results are pretty effectual and performance cognizant for predictive analytics. The manuscript and associated research work integrate the IoT and Internet of Everything (IoE) based analytics with sensor technologies with real-time data so that the overall predictions will be more accurate and integrated with the health sector. Supplementary Information: The online version contains supplementary material available at 10.1007/s12652-022-04395-7.

9.
Front Mol Biosci ; 8: 625391, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34124140

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first recognized in Wuhan in late 2019 and, since then, had spread globally, eventually culminating in the ongoing pandemic. As there is a lack of targeted therapeutics, there is certain opportunity for the scientific community to develop new drugs or vaccines against COVID-19 and so many synthetic bioactive compounds are undergoing clinical trials. In most of the countries, due to the broad therapeutic spectrum and minimal side effects, medicinal plants have been used widely throughout history as traditional healing remedy. Because of the unavailability of synthetic bioactive antiviral drugs, hence all possible efforts have been focused on the search for new drugs and alternative medicines from different herbal formulations. In recent times, it has been assured that the Mpro, also called 3CLpro, is the SARS-CoV-2 main protease enzyme responsible for viral reproduction and thereby impeding the host's immune response. As such, Mpro represents a highly specified target for drugs capable of inhibitory action against coronavirus disease 2019 (COVID-19). As there continue to be no clear options for the treatment of COVID-19, the identification of potential candidates has become a necessity. The present investigation focuses on the in silico pharmacological activity of Calotropis gigantea, a large shrub, as a potential option for COVID-19 Mpro inhibition and includes an ADME/T profile analysis of that ligand. For this study, with the help of gas chromatography-mass spectrometry analysis of C. gigantea methanolic leaf extract, a total of 30 bioactive compounds were selected. Our analyses unveiled the top four options that might turn out to be prospective anti-SARS-CoV-2 lead molecules; these warrant further exploration as well as possible application in processes of drug development to combat COVID-19.

10.
J Clin Invest ; 130(6): 2888-2902, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32078586

RESUMEN

Given the numerous health benefits of exercise, understanding how exercise capacity is regulated is a question of paramount importance. Circulating interleukin 6 (IL-6) levels surge during exercise and IL-6 favors exercise capacity. However, neither the cellular origin of circulating IL-6 during exercise nor the means by which this cytokine enhances exercise capacity has been formally established yet. Here we show through genetic means that the majority of circulating IL-6 detectable during exercise originates from muscle and that to increase exercise capacity, IL-6 must signal in osteoblasts to favor osteoclast differentiation and the release of bioactive osteocalcin in the general circulation. This explains why mice lacking the IL-6 receptor only in osteoblasts exhibit a deficit in exercise capacity of similar severity to the one seen in mice lacking muscle-derived IL-6 (mIL-6), and why this deficit is correctable by osteocalcin but not by IL-6. Furthermore, in agreement with the notion that IL-6 acts through osteocalcin, we demonstrate that mIL-6 promotes nutrient uptake and catabolism into myofibers during exercise in an osteocalcin-dependent manner. Finally, we show that the crosstalk between osteocalcin and IL-6 is conserved between rodents and humans. This study provides evidence that a muscle-bone-muscle endocrine axis is necessary to increase muscle function during exercise in rodents and humans.


Asunto(s)
Interleucina-6/inmunología , Músculo Esquelético/inmunología , Osteoblastos/inmunología , Transducción de Señal/inmunología , Animales , Femenino , Interleucina-6/genética , Macaca mulatta , Ratones , Ratones Noqueados , Transducción de Señal/genética
11.
Heliyon ; 6(1): e03310, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32051875

RESUMEN

TBP is a natural product from Tamarindus indica L. seeds used as a natural remedy in India. This product is an antioxidant and may have beneficial effects on endocrine and metabolic functions. However, the regulatory mechanisms involved remain to be elucidated. In males, testosterone is synthesized by Leydig cells from the testis. With aging and obesity, testis function declines, leading to decreased testosterone synthesis. The aim of the current research is to determine how TBP improves testosterone production in male mice under a high fat diet leading to hypoandrogenic condition. Using C2C12 myoblast cells, we have found that TBP increased mitochondrial mass and oxygen respiration, as well as the production of the IGF-1 hormone. In addition, treatment of TM3 Leydig cells with TBP resulted in increased testosterone production. In mice under a high fat diet, TBP lowered blood glucose level and corticosterone production and improved total testosterone production after five weeks of treatment. In addition, testicular expressions of genes encoding the mitochondrial transporter of cholesterol (Star) and steroidogenic enzymes (Cyp11a1, Hsd3b1, Cyp17a1 and Hsd17b3) were increased by TBP. Hence, TBP may prevent the detrimental effects of long-term consumption of a high fat diet and may have health benefits on the endocrine function.

12.
Cell Metab ; 30(5): 890-902.e8, 2019 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-31523009

RESUMEN

We hypothesized that bone evolved, in part, to enhance the ability of bony vertebrates to escape danger in the wild. In support of this notion, we show here that a bone-derived signal is necessary to develop an acute stress response (ASR). Indeed, exposure to various types of stressors in mice, rats (rodents), and humans leads to a rapid and selective surge of circulating bioactive osteocalcin because stressors favor the uptake by osteoblasts of glutamate, which prevents inactivation of osteocalcin prior to its secretion. Osteocalcin permits manifestations of the ASR to unfold by signaling in post-synaptic parasympathetic neurons to inhibit their activity, thereby leaving the sympathetic tone unopposed. Like wild-type animals, adrenalectomized rodents and adrenal-insufficient patients can develop an ASR, and genetic studies suggest that this is due to their high circulating osteocalcin levels. We propose that osteocalcin defines a bony-vertebrate-specific endocrine mediation of the ASR.


Asunto(s)
Huesos/metabolismo , Osteoblastos/metabolismo , Osteocalcina/sangre , Estrés Fisiológico/genética , Insuficiencia Suprarrenal/metabolismo , Adrenalectomía , Adulto , Animales , Células Cultivadas , Femenino , Ácido Glutámico/metabolismo , Voluntarios Sanos , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Persona de Mediana Edad , Neuronas/metabolismo , Osteocalcina/genética , Sistema Nervioso Parasimpático/citología , Ratas , Ratas Sprague-Dawley
13.
J Diabetes ; 9(5): 462-474, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27863006

RESUMEN

In search of direct targets of insulin-like growth factor (IGF)-1 action, we discovered CCN5 (WNT1 inducible signaling pathway protein 2 [WISP2]) as a novel protein expressed in pancreatic ß-cells. As a member of the "CCN" ( C ysteine-rich angiogenic inducer 61 [Cyr61], C onnective tissue growth factor [CTGF in humans], and N ephroblastoma overexpressed [Nov; in chickens]) family, the expression of CCN5/WISP2 is stimulated by IGF-1 together with Wnt signaling. When overexpressed in insulinoma cells, CCN5 promotes cell proliferation and cell survival against streptozotocin-induced cell death. The cell proliferation effect seems to be caused by AKT phosphorylation and increased cyclin D1 levels. These properties resemble those of CCN2/CTGF, another isoform of the CCN family, although CCN5 is the only one within the family of six proteins that lacks the C-terminal repeat. Treatment of primary mouse islets with recombinant CCN5 protein produced similar effects to those of gene transfection, indicating that either as a matricellular protein or a secreted growth factor, CCN5 stimulates ß-cell proliferation and regeneration in a paracrine fashion. This review also discusses the regulation of CCN5/WISP2 by estrogen and its involvement in angiogenesis and tumorigenesis.


Asunto(s)
Proteínas CCN de Señalización Intercelular/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Islotes Pancreáticos/efectos de los fármacos , Proteínas Represoras/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , Animales , Proteínas CCN de Señalización Intercelular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Supervivencia Celular/genética , Humanos , Islotes Pancreáticos/metabolismo , Ratones , Proteínas Represoras/genética
14.
Oncotarget ; 7(22): 32318-28, 2016 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-27086918

RESUMEN

Programmed death-ligand 1(PD-L1) expression on tumor cells is emerging as a potential predictive biomarker in anti-PD-L1 directed cancer immunotherapy. We analyzed PD-L1 expression in papillary thyroid carcinoma (PTC) and its variants and determined its prognostic potential to predict clinical outcome in these patients. This study was conducted at an academic oncology hospital which is a prime referral centre for thyroid diseases. Immunohistochemical subcellular localization (IHC) analyses of PD-L1 protein was retrospectively performed on 251 archived formalin fixed and paraffin embedded (FFPE) surgical tissues (66 benign thyroid nodules and 185 PTCs) using a rabbit monoclonal anti-PD-L1 antibody (E1L3N, Cell Signaling Technology) and detected using VECTASTAIN rapid protocol with diaminobenzidine (DAB) as the chromogen. The clinical-pathological factors and disease outcome over 190 months were assessed; immunohistochemical subcellular localization of PD-L1 was correlated with disease free survival (DFS) using Kaplan Meier survival and Cox multivariate regression analysis. Increased PD-L1 immunostaining was predominantly localized in cytoplasm and occasionally in plasma membrane of tumor cells. Among all combined stages of PTC, patients with increased PD-L1 membrane or cytoplasmic positivity had significantly shorter median DFS (36 months and 49 months respectively) as compared to those with PD-L1 negative tumors (DFS, both 186 months with p < 0.001 and p < 0.01 respectively). Comparison of PD-L1+ and PD-L1- patients with matched staging showed increased cytoplasmic positivity in all four stages of PTC that correlated with a greater risk of recurrence and a poor prognosis, but increased membrane positivity significantly correlated with a greater risk of metastasis or death only in Stage IV patients. In conclusion, PD-L1 positive expression in PTC correlates with a greater risk of recurrence and shortened disease free survival supporting its potential application as a prognostic marker for PTC.


Asunto(s)
Antígeno B7-H1/análisis , Biomarcadores de Tumor/análisis , Carcinoma Papilar/química , Neoplasias de la Tiroides/química , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Papilar/mortalidad , Carcinoma Papilar/secundario , Carcinoma Papilar/terapia , Distribución de Chi-Cuadrado , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Bocio Nodular/metabolismo , Bocio Nodular/patología , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Ontario , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/terapia , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
15.
PLoS One ; 10(8): e0136656, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26305481

RESUMEN

We have reported a high expression of IGF-I in pancreatic islet ß-cells of transgenic mice under the metallothionein promoter. cDNA microarray analysis of the islets revealed that the expression of 82 genes was significantly altered compared to wild-type mice. Of these, 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1), which is responsible for the conversion of inert cortisone (11-dehydrocorticosterone, DHC in rodents) to active cortisol (corticosterone) in the liver and adipose tissues, has not been identified previously as an IGF-I target in pancreatic islets. We characterized the changes in its protein level, enzyme activity and glucose-stimulated insulin secretion. In freshly isolated islets, the level of 11ß-HSD1 protein was significantly lower in MT-IGF mice. Using dual-labeled immunofluorescence, 11ß-HSD1 was observed exclusively in glucagon-producing, islet α-cells but at a lower level in transgenic vs. wild-type animals. MT-IGF islets also exhibited reduced enzymatic activities. Dexamethasone (DEX) and DHC inhibited glucose-stimulated insulin secretion from freshly isolated islets of wild-type mice. In the islets of MT-IGF mice, 48-h pre-incubation of DEX caused a significant decrease in insulin release, while the effect of DHC was largely blunted consistent with diminished 11ß-HSD1 activity. In order to establish the function of intracrine glucocorticoids, we overexpressed 11ß-HSD1 cDNA in MIN6 insulinoma cells, which together with DHC caused apoptosis and a significant decrease in proliferation. Both effects were abolished with the treatment of an 11ß-HSD1 inhibitor. Our results demonstrate an inhibitory effect of IGF-I on 11ß-HSD1 expression and activity within the pancreatic islets, which may mediate part of the IGF-I effects on cell proliferation, survival and insulin secretion.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/biosíntesis , Corticosterona/análogos & derivados , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Insulina/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Animales , Proliferación Celular , Corticosterona/metabolismo , Dexametasona/administración & dosificación , Glucagón/genética , Glucagón/metabolismo , Glucosa/metabolismo , Humanos , Insulina/genética , Secreción de Insulina , Factor I del Crecimiento Similar a la Insulina/genética , Islotes Pancreáticos/enzimología , Islotes Pancreáticos/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones , Ratones Transgénicos , Análisis de Secuencia por Matrices de Oligonucleótidos
16.
Growth Factors ; 33(1): 1-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25370781

RESUMEN

We have reported earlier that murine-regenerating gene mReg2 protects MIN6 mouse insulinoma cells from ER stress and caspase-mediated apoptosis. In apoptotic cells, DNA damage is induced by the nuclear translocation of mitochondrial apoptosis-inducing factor (AIF). Here we tested the hypothesis that mReg2 may regulate Scythe and/or hsp70 which influence the nuclear import of AIF. Treatment with thapsigargin (Tg) or doxorubicin induced an increase in nuclear AIF in MIN6 cells carrying the empty transfection vector (MIN6-VC) but not in cells overexpressing mReg2 (MIN6-mReg2). On one hand, nuclear Scythe was higher in the nucleus of MIN6-mReg2 compared with that in MIN6-VC cells. mReg2 did not alter the expression of AIF or Scythe. On the other hand, mReg2 induced the expression of hsp70 which is known to promote cytosolic retention of AIF. We conclude that mReg2 inhibits AIF-mediated apoptosis by promoting the nuclear presence of Scythe and inducing hsp70.


Asunto(s)
Factor Inductor de la Apoptosis/metabolismo , Núcleo Celular/metabolismo , Células Secretoras de Insulina/metabolismo , Proteínas/metabolismo , Transporte Activo de Núcleo Celular , Animales , Línea Celular Tumoral , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Ratones , Chaperonas Moleculares/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Asociadas a Pancreatitis , Proteínas/genética
17.
FEBS Lett ; 588(11): 2016-24, 2014 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-24801175

RESUMEN

Murine regenerating (mReg) genes have been implicated in preserving islet cell biology. Expanding on our previous work showing that overexpression of mReg2 protects MIN6 insulinoma cells against streptozotocin-induced apoptosis, we now demonstrate that mReg2 induces glucose-regulated peptide 78 (GRP78) expression via the Akt-mTORC1 axis and protects MIN6 cells against ER stress induced by thapsigargin and glucolipotoxicity. Activation of mTORC1 activity results from both mReg2-induced increased mTOR phosphorylation as well as increased expression of Raptor and GßL. Inhibition of Akt and mTORC1 blunted the ability of mReg2 to induce GRP78 and attenuate unfolded protein response (UPR). Knockdown of GRP78 sensitized the cells overexpressing mReg2 to UPR without affecting its ability to activate Akt-mTORC1 signaling. Induced expression of mReg2 may protect insulin producing cells from ER stress in diabetes.


Asunto(s)
Proteínas de Choque Térmico/metabolismo , Proteínas/fisiología , Respuesta de Proteína Desplegada , Factor de Transcripción Activador 6/metabolismo , Animales , Apoptosis , Línea Celular Tumoral , Chaperón BiP del Retículo Endoplásmico , Estrés del Retículo Endoplásmico , Endorribonucleasas/metabolismo , Proteínas de Choque Térmico/genética , Insulinoma , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Complejos Multiproteicos/metabolismo , Proteínas Asociadas a Pancreatitis , Fosforilación , Procesamiento Proteico-Postraduccional , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Activación Transcripcional
18.
Endocrinology ; 155(5): 1629-42, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24552398

RESUMEN

IGF-I is normally produced from hepatocytes and other sources, stimulates protein synthesis, cell survival, and proliferation through receptor-mediated activation of phosphatidylinositol 3-kinase and MAPK, and targets specific molecules within the pancreatic islet cells. The current study was designed to identify novel targets that may mediate its pro-islet actions. Whole-genome cDNA microarray analysis in IGF-I-overexpressing islets identified 82 genes specifically up- or down-regulated. Prominent among them was CCN5/WISP2 whose expression was increased 3- and 2-fold at the mRNA and protein levels. Dual-labeled immunofluorescence revealed that CCN5 expression was low in the ß-cells of wild-type islets but was significantly induced in response to IGF-I overexpression. In vitro treatment of mouse islets with IGF-I increased both CCN5 mRNA and protein levels significantly. To define the role of CCN5 in islet cell biology, we stably overexpressed its cDNA in insulinoma MIN6 cells and detected a 2-fold increase in the proliferation of MIN6-CCN5 compared with that in control cells, which correlated with significant elevations in the levels of cyclin D1 and the phosphorylation of Akt and Erk2. Moreover, MIN6-CCN5 cells were found to be resistant to streptozotocin-induced cell death. Using confocal microscopy and subcellular fractionation, we found that overexpressed CCN5 exhibited cytoplasmic accumulation upon stimulation by high glucose. Our results indicate that CCN5, which is minimally expressed in islet ß-cells, is strongly and directly induced by IGF-I. CCN5 overexpression stimulates the proliferation of insulinoma cells, activates Akt kinase, and inhibits streptozotocin-induced apoptosis, suggesting that increased CCN5 expression contributes to IGF-I-stimulated islet cell growth and/or survival.


Asunto(s)
Apoptosis/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Estreptozocina/farmacología , Regulación hacia Arriba/efectos de los fármacos , Animales , Antibióticos Antineoplásicos/farmacología , Línea Celular , Proliferación Celular/efectos de los fármacos , Ciclina D1/biosíntesis , Ciclina D1/genética , Ciclina D1/metabolismo , Resistencia a Medicamentos , Silenciador del Gen , Humanos , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Factor I del Crecimiento Similar a la Insulina/genética , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/genética , Islotes Pancreáticos/citología , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Técnicas de Cultivo de Tejidos
19.
Regul Pept ; 186: 83-91, 2013 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-23954400

RESUMEN

Poly(ADP-ribose) polymerase (Parp) 1 is a key regulator of cell death, its inhibition prevented streptozotocin-induced diabetes and attenuated caerulein-induced acute pancreatitis. Reg family proteins are significantly induced by Parp1 inhibitor, experimental diabetes and/or acute pancreatitis. We propose that Reg proteins are involved in the protection of pancreatic cells by Parp1 inhibition. To test this possibility, Parp1-/- and wild-type mice were injected with streptozotocin to induce diabetes. Separately, acute pancreatitis was induced with repeated injections of caerulein. Upon streptozotocin administration, Parp1-/- mice displayed much decreased hyperglycemia and preserved serum insulin level. The treatment induced similar levels of Reg1, -2, -3α and -3ß genes in the pancreas of both wild-type and Parp1-/- mice, suggesting that the upregulation of Reg family genes during streptozotocin-induced diabetes was independent of Parp1 ablation. In caerulein-induced pancreatitis, unlike being reported, Parp1 knockout caused no relief on the severity of pancreatitis; the upregulation of pancreatic Reg1, -2, -3α and -3ß genes upon caerulein was unaffected by Parp1 deletion. Our results reconfirmed the protective effect of Parp1 gene deletion on islet ß-cells but questioned its effect on the acinar cells. In either case, the significant induction of Reg family genes seemed independent of Parp1-mediated cell death.


Asunto(s)
Diabetes Mellitus Experimental/enzimología , Litostatina/genética , Pancreatitis/enzimología , Poli(ADP-Ribosa) Polimerasas/deficiencia , Animales , Ceruletida , Diabetes Mellitus Experimental/inducido químicamente , Transportador de Glucosa de Tipo 2/genética , Transportador de Glucosa de Tipo 2/metabolismo , Células Secretoras de Insulina/metabolismo , Litostatina/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Ratones Noqueados , Pancreatitis/inducido químicamente , Poli(ADP-Ribosa) Polimerasa-1 , Poli(ADP-Ribosa) Polimerasas/genética , Estreptozocina , Activación Transcripcional , Regulación hacia Arriba
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