Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 121
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 120(39): e2302292120, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37722044

RESUMO

As a major sink of anthropogenic heat and carbon, the Southern Ocean experienced pronounced warming with increasing extreme temperature events over the past decades. Mesoscale eddies that strongly influence the uptake, redistribution, and storage of heat in the ocean are expected to play important roles in these changes, yet observational evidence remains limited. Here, we employ a comprehensive analysis of over 500,000 historical hydrographic profile measurements combined with satellite-based eddy observations to show enhanced thermal eddy imprints in the Southern Ocean. Our observations reveal that anticyclonic (cyclonic) eddies are responsible for nearly half of the subsurface high (low)-temperature extremes detected, although only 10% of the profiles are located in eddy interiors. Over the past decade (2006 to 2019), both mean and extreme temperature anomalies within eddies in the Antarctic Circumpolar Current increased significantly, promoting the rise in subsurface ocean temperature variability. This enhanced role of eddies is likely a result of enhanced eddy pumping due to the increase in eddy intensity and ocean stratification caused by ocean warming. Our analysis underscores the crucial role of eddies in amplifying ocean temperature variability and extremes, with their effects expected to be even more pronounced as global warming persists.

2.
BMC Genomics ; 25(1): 219, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413888

RESUMO

BACKGROUND: Intramuscular fat (IMF) is an important factor in meat quality, and triglyceride (TG) and Phospholipids (PLIP), as the main components of IMF, are of great significance to the improvement of meat quality. RESULTS: In this study, we used 30 RNA sequences generated from the transcriptome of chicken breast muscle tissues at different developmental stages to construct a gene expression matrix to map RNA sequence reads to the chicken genome and identify the transcript of origin. We used weighted gene co-expression network analysis (WGCNA) and identified 27 co-expression modules, 10 of which were related to TG and PLIP. We identified 150 highly-connected hub genes related to TG and PLIP, respectively, which were found to be mainly enriched in the adipocytokine signaling pathway, MAPK signaling pathway, mTOR signaling pathway, FoxO signaling pathway, and TGF-beta signaling pathway. Additionally, using the BioMart database, we identified 134 and 145 candidate genes related to fat development in the TG-related module and PLIP-related module, respectively. Among them, RPS6KB1, BRCA1, CDK1, RPS3, PPARGC1A, ACSL1, NDUFAB1, NDUFA9, ATP5B and PRKAG2 were identified as candidate genes related to fat development and highly-connected hub genes in the module, suggesting that these ten genes may be important candidate genes affecting IMF deposition. CONCLUSIONS: RPS6KB1, BRCA1, CDK1, RPS3, PPARGC1A, ACSL1, NDUFAB1, NDUFA9, ATP5B and PRKAG2 may be important candidate genes affecting IMF deposition. The purpose of this study was to identify the co-expressed gene modules related to chicken IMF deposition using WGCNA and determine key genes related to IMF deposition, so as to lay a foundation for further research on the molecular regulation mechanism underlying chicken fat deposition.


Assuntos
Galinhas , Músculos , Animais , Galinhas/genética , Galinhas/metabolismo , Músculos/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Análise de Sequência de RNA
3.
Small ; 20(1): e2302440, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37668280

RESUMO

The perception of temperature and pressure of skin plays a vital role in joint movement, hand grasp, emotional expression, and self-protection of human. Among many biomimetic materials, ionic gels are uniquely suited to simulate the function of skin due to its ionic transport mechanism. However, both the temperature and pressure sensing are heavily dependent on the changes in ionic conductivity, making it impossible to decouple the temperature and pressure signals. Here, a pressure-insensitive and temperature-modulated ion channel is designed by synergistic strategies for gel skeleton's compact packing and ultra-thin structure, mimicking the function of the temperature ion channel in human skin. This ion-confined gel can completely suppress the pressure response of the temperature sensing layer. Furthermore, a temperature-pressure decoupled ionic sensor is fabricated and it is demonstrated that the ionic sensor can sense complex signals of temperature and pressure. This novel and effective approach has great potential to overcome one of the current barriers in developing ionic skin and extending its applications.


Assuntos
Biomimética , Percepção do Tato , Humanos , Temperatura , Tato/fisiologia , Canais Iônicos
4.
Small ; 20(11): e2308875, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37880900

RESUMO

As a new approach to "More than Moore", integrated ionic circuits serve as a possible alternative to traditional electronic circuits, yet the integrated ionic circuit composed of functional ionic elements and ionic connections is still challenging. Herein, a stretchable and transparent ionic display module of the integrated ionic circuit has been successfully prepared and demonstrated by pixelating a proton-responsive hydrogel. It is programmed to excite the hydrogel color change by a Faraday process occurring at the electrode at the specific pixel points, which enables the display of digital information and even color information. Importantly, the display module exhibits stable performance under strong magnetic field conditions (1.7 T). The transparent and stretchable nature of such ionic modules also allows them to be utilized in a broad range of scenarios, which paves the way for integrated ionic circuits.

5.
Int J Mol Sci ; 25(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38673925

RESUMO

The protective effects of hydrogen sulfide (H2S) against ischemic brain injury and its role in promoting angiogenesis have been established. However, the specific mechanism underlying these effects remains unclear. This study is designed to investigate the regulatory impact and mechanism of H2S on VEGFR2 phosphorylation. Following expression and purification, the recombinant His-VEGFR2 protein was subjected to LC-PRM/MS analysis to identify the phosphorylation sites of VEGFR2 upon NaHS treatment. Adenovirus infection was used to transfect primary rat brain artery endothelial cells (BAECs) with the Ad-VEGFR2WT, Ad-VEGFR2Y797F, and Ad-VEGFR2S799A plasmids. The expression of VEGFR2 and recombinant Flag-VEGFR2, along with Akt phosphorylation, cell proliferation, and LDH levels, was assessed. The migratory capacity and tube-forming potential of BAECs were assessed using wound healing, transwell, and tube formation assays. NaHS notably enhanced the phosphorylation of VEGFR2 at Tyr797 and Ser799 sites. These phosphorylation sites were identified as crucial for mediating the protective effects of NaHS against hypoxia-reoxygenation (H/R) injury. NaHS significantly enhanced the Akt phosphorylation, migratory capacity, and tube formation of BAECs and upregulated the expression of VEGFR2 and recombinant proteins. These findings suggest that Tyr797 and Ser799 sites of VEGFR2 serve as crucial mediators of H2S-induced pro-angiogenic effects and protection against H/R injury.


Assuntos
Células Endoteliais , Sulfeto de Hidrogênio , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Fosforilação/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Animais , Ratos , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Ratos Sprague-Dawley , Hipóxia Celular , Proliferação de Células/efeitos dos fármacos , Tirosina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Indutores da Angiogênese/farmacologia , Indutores da Angiogênese/metabolismo , Serina/metabolismo , Hipóxia/metabolismo
6.
Langmuir ; 39(47): 16927-16934, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37967407

RESUMO

Sufficient efforts have been put into the design of anti-icing materials to eliminate the icing hazard. Among the currently approved anti-icing concepts, hydrophilic/hydrophobic hybrid anti-icing materials inspired by antifreeze proteins show excellent properties in inhibiting ice nucleation, inhibiting ice crystal growth, and reducing ice adhesion. However, it is still a great challenge to accurately regulate the hydrophilic and hydrophobic hybrid components of the coating surface to clarify the synergistic mechanism. This work proposes a strain-manipulated surface modification strategy, and an anti-icing coating with adjustable hydrophilic/hydrophobic hybrid components prepared by combining chemical vapor deposition and siloxane chemistry is obtained. According to the ice resistance experiment at -15 °C, the performance of anti-icing is closely related to the proportion of hydrophilic and hydrophobic hybrids. The icing delay time and ice adhesion strength of the material with the optimal hydrophilic/hydrophobic components are 280 s and 18.6 kPa, respectively. These unique properties can be attributed to the synergistic effect of hydrophilic and hydrophobic structures on the regulation of interfacial water.

7.
J Mater Sci Mater Med ; 34(7): 35, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37477830

RESUMO

Peripheral nerve injury (PNI) is a common and severe clinical disease worldwide, which leads to a poor prognosis because of the complicated treatments and high morbidity. Autologous nerve grafting as the gold standard still cannot meet the needs of clinical nerve transplantation because of its low availability and limited size. The development of artificial nerve conduits was led to a novel direction for PNI treatment, while most of the currently developed artificial nerve conduits was lack biochemical cues to promote nerve regeneration. In this study, we designed a novel composite neural conduit by inserting decellularized the rat sciatic nerve or kidney in a poly (lactic-co-glycolic acid) (PLGA) grooved conduit. The nerve regeneration effect of all samples was analyzed using rat sciatic nerve defect model, where decellularized tissues and grooved PLGA conduit alone were used as controls. The degree of nerve regeneration was evaluated using the motor function, gastrocnemius recovery, and morphological and histological assessments suggested that the combination of a grooved conduit with decellularized tissues significantly promoted nerve regeneration compared with decellularized tissues and PLGA conduit alone. It is worth to note that the grooved conduits containing decellularized nerves have a promotive effect similar to that of autologous nerve grafting, suggesting that it could be an artificial nerve conduit used for clinical practice in the future.


Assuntos
Ácido Láctico , Traumatismos dos Nervos Periféricos , Ratos , Animais , Ácido Láctico/farmacologia , Nervo Isquiático/fisiologia , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/terapia , Traumatismos dos Nervos Periféricos/patologia , Próteses e Implantes
8.
Microvasc Res ; 141: 104309, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34995553

RESUMO

INTRODUCTION: The aim of present study was to study whether the vascular endothelial growth factor receptor 2 (VEGFR2) mediates hydrogen sulfide (H2S)-induced relaxation of the rat cerebral vasculature. METHODS: Relaxation of cerebral basilar artery (CBA) and vascular smooth muscle cells (VSMCs) was measured by using a pressure myograph system and image analysis system, respectively. The intracellular calcium concentration ([Ca2+]i) in VSMCs was detected using fluorescence imaging analysis. RESULTS: We found that H2S donor NaHS induced significant relaxation of VSMCs from the CBA of wild type rat, but in VEGFR2 knockdown VSMCs, NaHS-induced relaxation reduced markedly. In addition, NaHS-induced vasodilation of rat CBA also attenuated obviously when the expression of VEGFR2 was knocked down in vivo. In addition, pretreatment with the VEGFR2 blocker SU5416 likewise lowered the NaHS-induced relaxation of rat CBA. Nevertheless, the VEGFR2 agonist, vascular endothelial growth factor 164 (VEGF164), induced a concentration-dependent relaxation of CBA, which is similar to the effect of NaHS. Furthermore, we found that both NaHS and VEGF164 significantly inhibited the U46619-induced increase of [Ca2+]i fluorescence intensity in the VSMCs. However, the inhibitory effect of NaHS on the [Ca2+]i fluorescence intensity in VSMCs was markedly inhibited by pretreatment with SU5416 or VEGFR2 knockdown. CONCLUSION: These findings indicated that H2S-induced CBA dilation and reduction of [Ca2+]i in VSMCs occur by acting on VEGFR2.


Assuntos
Sulfeto de Hidrogênio , Músculo Liso Vascular , Animais , Artéria Basilar/metabolismo , Dilatação , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
9.
Molecules ; 27(14)2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35889443

RESUMO

The RhoA-ROCK signaling pathway is associated with the protective effects of hydrogen sulfide (H2S) against cerebral ischemia. H2S protects rat hippocampal neurons (RHNs) against hypoxia-reoxygenation (H/R) injury by promoting phosphorylation of RhoA at Ser188. However, effect of H2S on the phosphorylation of ROCK2-related sites is unclear. The present study was designed to investigate whether H2S can play a role in the phosphorylation of ROCK2 at Tyr722, and explore whether this role mediates the protective effect of H/R injury in RHNs. Prokaryotic recombinant plasmids ROCK2wild-pGEX-6P-1 and ROCK2Y722F-pGEX-6P-1 were constructed and transfected into E. coli in vitro, and the expressed protein, GST-ROCK2wild and GST-ROCK2Y722F were used for phosphorylation assay in vitro. Eukaryotic recombinant plasmids ROCK2Y722-pEGFP-N1 and ROCK2Y722F-pEGFP-N1 as well as empty plasmid were transfected into the RHNs. Western blot assay and whole-cell patch-clamp technique were used to detect phosphorylation of ROCK2 at Tyr722 and BKCa channel current in the RHNs, respectively. Cell viability, leakages of intracellular enzymes lactate dehydrogenase (LDH), and nerve-specific enolase (NSE) were measured. The H/R injury was indicated by decrease of cell viability and leakages of intracellular LDH and NSE. The results of Western blot have shown that NaHS, a H2S donor, significantly promoted phosphorylation of GST-ROCK2wild at Tyr722, while no phosphorylation of GST-ROCK2Y722F was detected. The phosphorylation of ROCK2wild promoted by NaHS was also observed in RHNs. NaHS induced more potent effects on protection against H/R injury, phosphorylation of ROCK2 at Tyr722, inhibition of ROCK2 activity, as well as increase of the BKCa current in the ROCK2Y722-pEGFP-N1-transfected RHNs. Our results revealed that H2S protects the RHNs from H/R injury through promoting phosphorylation of ROCK2 at Tyr722 to inhibit ROCK2 activity and potentially by opening channel currents.


Assuntos
Escherichia coli , Sulfeto de Hidrogênio , Animais , Escherichia coli/metabolismo , Hipocampo/metabolismo , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Hipóxia/metabolismo , Neurônios , Ratos
10.
Metab Brain Dis ; 36(6): 1101-1108, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33745103

RESUMO

Ischemic stroke is one of the most common and undertreated cerebral diseases with high mortality and disability rate. Various intrinsic and extrinsic factors regulate the onset, severity, and progression of ischemic stroke. As an integral part of the neuronal glia system, astrocytes provide many housekeeping functions in nervous system, and perform multiple functions both beneficial and detrimental for neuronal survival after ischemic stroke. In addition, the small GTPase Rho and its downstream Rho kinase (ROCK) are associated with various neuronal functions such as dendrite development, migration and axonal extension, and numerous central nervous system (CNS) diseases. The aim of this review is to summarize the role of RhoA/ROCK signaling pathway and astrocytes on neurological function after ischemic stroke. We also discuss the interaction of RhoA/ROCK signaling pathway and astrocytes on the tissue repair after brain injury.


Assuntos
Astrócitos/metabolismo , Isquemia Encefálica/metabolismo , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Humanos , Neurogênese/fisiologia , Neurônios/metabolismo
11.
Am J Physiol Cell Physiol ; 319(4): C720-C733, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32813542

RESUMO

3-Mercaptopyruvate sulfurtransferase (3-MST) is the major source of hydrogen sulfide (H2S) production in the brain and participates in many physiological and pathological processes. The present study was designed to investigate the role of 3-MST-derived H2S (3-MST/H2S) on oxygen-glucose deprivation/reoxygenation (OGD/R) injury in cerebrovascular endothelial cells (ECs). Using cerebrovascular specimens from patients with acute massive cerebral infarction (MCI), we found abnormal morphology of the endothelium and mitochondria, as well as decreases in H2S and 3-MST levels. In an OGD/R model of ECs, 3-mercaptopyruvate (3-MP) and l-aspartic acid (l-Asp) were used to stimulate or inhibit the production of 3-MST/H2S. The results showed that OGD/R induced significant decreases in H2S and 3-MST levels in both ECs and mitochondria, as well as increases in oxidative stress and mitochondrial energy imbalance. Cellular oxidative stress, destruction of mitochondrial ultrastructure, accumulation of mitochondrial reactive oxygen species (ROS), reduction of mitochondrial adenosine triphosphate (ATP) synthase activity and ATP production, and decreased mitochondrial membrane potential were all significantly ameliorated by 3-MP, whereas they were exacerbated by l-Asp pretreatment. Contrary to the effects of l-Asp, the increase in RhoA activity and expression of ROCK1 and ROCK2 induced by OGD/R were markedly inhibited by 3-MP pretreatment in subcellular fractions without mitochondria and mitochondrial fractions. In addition, 3-MST-/- rat ECs displayed greater oxidative stress than 3-MST+/+ rat ECs after OGD/R injury. These findings suggest that 3-MST/H2S protects ECs against OGD/R-induced injury, which may be related to preservation of mitochondrial function and inhibition of the RhoA/ROCK pathway.


Assuntos
Mitocôndrias/genética , Sulfurtransferases/genética , Proteínas rho de Ligação ao GTP/genética , Quinases Associadas a rho/genética , Trifosfato de Adenosina/biossíntese , Animais , Ácido Aspártico/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Cisteína/análogos & derivados , Cisteína/farmacologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Glucose/metabolismo , Sulfeto de Hidrogênio/metabolismo , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Oxigênio/metabolismo , Substâncias Protetoras , Ratos , Espécies Reativas de Oxigênio/metabolismo
12.
Pharmacology ; 105(1-2): 3-8, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31537002

RESUMO

Cerebral ischemic injury is one of the main causes of adult disability and death. Although significant progress has been made, cerebral ischemia continues to be a major risk to public health worldwide. The Rho kinase (ROCK) signaling pathway has been reported to be significantly involved in many mechanisms of cerebral injury. Although ROCK is ubiquitously expressed in all tissues, ROCK2 subtype expression in brain and the spinal cord is more abundant and improves with age. This makes it a promising target for new therapeutic approaches. In this article, we review the current knowledge on the involvement of ROCK in cerebral ischemia injury and neurodegenerative changes after cerebral injury. After a detailed description of the mechanism of ROCK involvement in axonal regeneration and synaptic function, different roles of ROCK1 and ROCK2 in neurons under physiological and pathological conditions are compared and discussed. In addition, different functions of genetic and pharmacological inhibitions of ROCK1 and ROCK2 on cerebral injury are discussed.


Assuntos
Isquemia Encefálica/metabolismo , Quinases Associadas a rho/metabolismo , Animais , Axônios/fisiologia , Isquemia Encefálica/fisiopatologia , Hipocampo/fisiologia , Humanos , Aprendizagem/fisiologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/fisiopatologia , Regeneração , Sinapses/fisiologia , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/fisiologia
13.
J Med Virol ; 91(5): 803-812, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30570770

RESUMO

Interleukin 6 (IL-6) is a pleiotropic cytokine with pivotal functions in the regulation of the biological responses of several target cells, including hepatocytes. Previous studies have shown that serum IL-6 levels are increased in hepatitis B patients. However, the role of IL-6 in modulating the anti-hepatitis B virus (HBV) activity of interferon-α (IFN-α) remains unclear. In this study, we found that both HBV and viral proteins could induce the expression of IL-6 in hepatocytes (LO2 and HepG2). Exogenous IL-6 had no effect on HBV replication, whereas knockdown of IL-6 expression by RNAi inhibited that. Interestingly, IFN-α markedly induced IL-6 expression in hepatocytes, especially in HBV replicating hepatocytes. In turn, IL-6 impaired the anti-HBV efficiency of IFN-α by decreases the expression of IFN-α downstream effectors by upregulation of suppressor of cytokine signaling-3 (SOCS3). Furthermore, we demonstrated that downregulation of SOCS3 improved IFN antiviral activity to some extent in HBV replicating hepatocytes. These data provided new insights for a better understanding of the mechanism of IFN-α resistance and may represent a novel therapeutic strategy to efficiently target HBV infection.


Assuntos
Antivirais/antagonistas & inibidores , Vírus da Hepatite B/imunologia , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Interferon-alfa/antagonistas & inibidores , Interleucina-6/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Linhagem Celular , Hepatócitos/virologia , Humanos
14.
Inflammopharmacology ; 27(6): 1309-1318, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31168686

RESUMO

SB-706375 is a selective receptor antagonist of human urotensin-II (hU-II), which can block the aorta contraction induced by hU-II in rats. The effect of SB-706375 on myocardial ischaemia-reperfusion (I/R) injury is unclear. The major objective of this study was to investigate whether SB-706375 has a protective effect on myocardial I/R injury in rats and explore its possible mechanisms. Isolated hearts of Adult Sprague-Dawley were perfused in a Langendorff apparatus, and haemodynamic parameters, lactate dehydrogenase (LDH), creatine phosphokinase-MB (CK-MB), cardiac troponin I (cTnI), RhoA, and the protein expressions of U-II receptor (UTR), receptor-interacting protein 3 (RIP3), Rho-associated coiled-coil-containing protein kinase 1 (ROCK1) and Rho-associated coiled-coil-containing protein kinase 2 (ROCK2) were assessed. We found that SB-706375 (1 × 10-6 and 1 × 10-5 mol/L) significantly inhibited the changes of haemodynamic parameters and reduced LDH and CK-MB activities and also cTnI level in the coronary effluents in the heart subjected to myocardial I/R injury. Further experiments studies showed that SB-706375 obviously prevented myocardial I/R increased RhoA activity and UTR, RIP3, ROCK1, and ROCK2 protein expressions. ROCK inhibition abolished the improving effect of SB-706375 on myocardial I/R-induced haemodynamic change in the isolated perfused rat heart. These findings suggested that SB-706375 provides cardio-protection against I/R injury in isolated rats by blocking UTR-RhoA/ROCK-RIP3 pathway.


Assuntos
Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/patologia , Pirrolidinas/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Sulfonamidas/farmacologia , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Quinases Associadas a rho/antagonistas & inibidores , Animais , Feminino , Masculino , Necrose , Ratos , Ratos Sprague-Dawley , Proteína Serina-Treonina Quinases de Interação com Receptores/fisiologia , Receptores Acoplados a Proteínas G/análise , Transdução de Sinais/fisiologia , Proteínas rho de Ligação ao GTP/fisiologia , Quinases Associadas a rho/fisiologia
15.
J Chem Ecol ; 44(10): 905-914, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30097768

RESUMO

Female-released chemical signals are crucial clues for mate-searching males to locate and gain sexual receptivity of conspecific females. Abundant behavioral evidence indicates that female spiders release sex pheromones to guide mate-searching behavior of conspecific mature males. However, the chemical nature of spider pheromones is poorly understood. Females of the funnel-web spider, Allagelena difficilis, employ sit-and-wait tactics for mating. Field observations indicate that males leave their retreats to search for potential mates during the breeding season. Therefore, we investigated whether virgin females release a sex attractant to conspecific males and then explored the chemical nature of the female pheromone. Four fatty acids extracted from the female bodies (palmitic acid, linoleic acid, cis-vaccenic acid and stearic acid) constitute a multiple-component sex attractant to conspecific males in A. difficilis. Unexpectedly, mated females also produce the same fatty acids, but at trace levels. Two-choice experiments showed that males were significantly attracted by the blend of the four fatty acids in appropriate concentrations while avoiding the blend consisting of the same acids at very low concentrations, suggesting that mate-searching males are able to discriminate virgin females from mated females by the quantities of female-specific fatty acids in the funnel-web spider A. difficilis.


Assuntos
Odorantes/análise , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Aranhas/efeitos dos fármacos , Animais , Feminino , Masculino , Atrativos Sexuais/química , Atrativos Sexuais/metabolismo , Aranhas/metabolismo , Volatilização
16.
Zhongguo Zhong Yao Za Zhi ; 42(24): 4782-4787, 2017 Dec.
Artigo em Zh | MEDLINE | ID: mdl-29493147

RESUMO

The results of a toxicity analysis showed differences from those of the existing experimental data. Therefore, HPLC-ICP-MS was used to analyze the soluble arsenic content at different valences in realgar prepared with water grind processing, which were collected from 3 companies. The results showed that the free arsenic of the 3 companies did not exceed the limit of Chinese Pharmacopoeia. However, if the free arsenic was calculated based on the total value of As(Ⅲ) + As(Ⅴ), free arsenic of 1 company exceeded the limit of Chinese Pharmacopoeia. The method of determining free arsenic in Chinese Pharmacopoeia. was ancient Cai's arsenic detection method, which had a certain limitation and failed to effectively avoid the toxicity of remaining arsenics except for trivalent arsenic. Then, we examined the effects of water and temperature on the content and form of soluble arsenic in realgar. The results showed that the content of soluble arsenic increased with the rise of water content, and the form of soluble arsenic did not change, there were only As (Ⅲ) and As (Ⅴ); With the simple temperature factor, there was an increasing trend in the content of soluble arsenic in the samples, the maximum increment was As (Ⅲ) 2.489 mg•g⁻¹ and As (Ⅴ) 0.546 mg•g⁻¹; When water and temperature played an synergistic effect, the increase of soluble arsenic in the samples significantly changed, the maximum increment was As (Ⅲ) 23.690 mg•g⁻¹, As (Ⅴ) 0.468 mg•g⁻¹, respectively. Through comprehensive analysis, we believed that the quality of realgar was susceptible to water content and temperature. Both of the single effect of water content and the synergistic effect of water and temperature can significantly change the content of soluble arsenic in realgar, and the water content was a high-risk factor. In the current Chinese Pharmacopoeia 2015 version, the free arsenic detection method had limitations, hence new techniques shall be introduced; At the same time, realgar does not have a water content inspection item in the current pharmacopoeia, which shall be added. However, due to the limit of water content, more in-depth studies are required.


Assuntos
Arsênio/análise , Arsenicais/análise , Sulfetos/análise , Cromatografia Líquida de Alta Pressão , Sulfetos/toxicidade
17.
J Vasc Res ; 53(3-4): 172-185, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27732975

RESUMO

BACKGROUND/AIM: H2S is a novel vasoactivator. To verify the hypothesis that H2S may act as an endothelium-derived hyperpolarizing factor (EDHF) in the rat cerebrovasculature, the role of H2S in endothelium-derived relaxing factor (EDRF)-mediated responses was investigated. METHODS: Cystathionine-γ-lyase (CSE) was knocked down with an siRNA technique. Artery diameter, hyperpolarization and Ca2+-activated K+ (KCa) current were measured. RESULTS: CSE knockdown was indicated by a decrease in protein and mRNA expression in the rat middle cerebral artery (MCA) and cerebral basilar artery (CBA). Acetylcholine (ACh) induced significant hyperpolarization and vasodilation in endothelium-intact MCA and CBA. Removal of the endothelium abolished these responses. The nitric oxide (NO) synthase inhibitor L-NAME, but not the PGI2 production inhibitor indomethacin, significantly inhibited ACh-induced hyperpolarization and vasodilation in the CBA. In the presence of L-NAME and indomethacin, ACh-induced hyperpolarization and vasodilation in the MCA and CBA were attenuated. The non-NO/PGI2-mediated responses were abolished by the KCa channel blockers charybdotoxin and apamin. In the cerebral arteries from the CSE knockdown rat, non-NO/PGI2-mediated responses were significantly attenuated, and the remaining responses were abolished by charybdotoxin and apamin or the CSE inhibitor propargylglycine. CSE knockdown did not affect L-NAME-sensitive responses in the CBA. Sodium hydrosulfide (NaHS) augmented the KCa current in CBA vascular smooth muscle cells. CONCLUSION: EDHF-mediated responses in rat cerebral arteries were due to H2S activating the KCa channel.


Assuntos
Artéria Basilar/metabolismo , Fatores Biológicos/metabolismo , Sulfeto de Hidrogênio/metabolismo , Artéria Cerebral Média/metabolismo , Vasodilatação , Animais , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/enzimologia , Inibidores de Ciclo-Oxigenase/farmacologia , Cistationina gama-Liase/genética , Cistationina gama-Liase/metabolismo , Relação Dose-Resposta a Droga , Epoprostenol/metabolismo , Masculino , Potenciais da Membrana , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/enzimologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio Cálcio-Ativados/metabolismo , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Ratos Sprague-Dawley , Transdução de Sinais , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
18.
BMC Cancer ; 16: 246, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27012847

RESUMO

BACKGROUND: ACFP is an anti-cancer fusion peptide derived from bovine milk protein. This study was to investigate the anti-cancer function and underlying mechanisms of ACFP in ovarian cancer. METHODS: Fresh ovarian tumor tissues were collected from 53 patients who underwent initial debulking surgery, and primary cancer cells were cultured. Normal ovarian surface epithelium cells (NOSECs), isolated from 7 patients who underwent surgery for uterine fibromas, were used as normal control tissue. Anti-viabilities of ACFP were assessed by WST-1 (water-soluble tetrazolium 1), and apoptosis was measured using a flow cytometry-based assay. Gene expression profiles of ovarian cancer cells treated with ACFP were generated by cDNA microarray, and the expression of apoptotic-specific genes, such as bcl-xl, bax, akt, caspase-3, CDC25C and cyclinB1, was assessed by real time PCR and western blot analysis. RESULTS: Treatment with ACFP inhibited the viability and promoted apoptosis of primary ovarian cancer cells but exhibited little or no cytotoxicity toward normal primary ovarian cells. Mechanistically, the anti-cancer effects of ACFP in ovarian cells were shown to occur partially via changes in gene expression and related signal pathways. Gene expression profiling highlighted that ACFP treatment in ovarian cancer cells repressed the expression of bcl-xl, akt, CDC25C and cyclinB1 and promoted the expression of bax and caspase-3 in a time- and dose-dependent manner. CONCLUSIONS: Our results suggest that ACFP may represent a potential therapeutic agent for ovarian cancer that functions by altering the expression and signaling of cancer-related pathways in ovarian cancer cells.


Assuntos
Proteínas do Leite/administração & dosagem , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Neoplasias Ovarianas/tratamento farmacológico , Peptídeos/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Caspase 3/biossíntese , Bovinos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina B1/biossíntese , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/biossíntese , Fosfatases cdc25/biossíntese
19.
J Surg Res ; 206(2): 307-315, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27884324

RESUMO

BACKGROUND: Severe hemorrhage shock and resuscitation are a systemic ischemia-reperfusion phenomenon which can induce learning and memory deficit in human and rats. Sevoflurane postconditioning has been proved to offer neuroprotection under different setting of cerebral ischemia-reperfusion in rats. The aim of this study was to investigate whether sevoflurane postconditioning could improve spatial learning and memory ability after hemorrhage shock and resuscitation in rats. METHODS: Thirty-five male rats were randomized into five groups: sham group, shock group, low concentration (sevo1, 1.2%), middle concentration (sevo2, 2.4%), and high concentration (sevo3, 3.6%) of sevoflurane postconditioning groups. The spatial learning and memory ability of rats were measured by Morris water maze 3 d after the operation. The expression of choline acetyltransferase (CHAT) and acetylcholinesterase (ACHE) in the hippocampus CA1 region was observed by immunohistochemistry method after the Morris water maze test. RESULTS: The ability of spatial learning and memory of rats and the expression of CHAT was significantly declined, while the expression of ACHE increased in the shock group compared with the sham group (P < 0.05). Sevoflurane postconditioning with the concentrations of 2.4% and 3.6% significantly ameliorated the spatial learning and memory ability and increased the expression of CHAT and decreased the expression of ACHE in hippocampal CA1 region when compared with shock group (P < 0.05). CONCLUSIONS: Postconditioning with sevoflurane at the concentrations of 2.4% and 3.6% which improved the ability of spatial learning and memory after hemorrhage shock and resuscitation in rats may involve the protection of the cholinergic neurons in hippocampal CA1 region.


Assuntos
Pós-Condicionamento Isquêmico/métodos , Éteres Metílicos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Ressuscitação , Choque Hemorrágico/terapia , Animais , Biomarcadores/metabolismo , Colina O-Acetiltransferase/metabolismo , Neurônios Colinérgicos/efeitos dos fármacos , Neurônios Colinérgicos/metabolismo , Hipocampo/irrigação sanguínea , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Deficiências da Aprendizagem/etiologia , Deficiências da Aprendizagem/prevenção & controle , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/etiologia , Transtornos da Memória/prevenção & controle , Éteres Metílicos/farmacologia , Fármacos Neuroprotetores/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/etiologia , Sevoflurano , Choque Hemorrágico/complicações , Aprendizagem Espacial/efeitos dos fármacos , Resultado do Tratamento
20.
Can J Physiol Pharmacol ; 94(12): 1309-1314, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27533316

RESUMO

Sufentanil has been used broadly in cardiac surgery, but the mechanisms by which it modulates coronary vascular tone after ischemia-reperfusion injury are largely unknown. Effects of sufentanil on coronary tone and on the relaxation of rat coronary arteries (CAs) in response to endothelium-dependent (acetylcholine) and endothelium-independent (sodium nitroprusside) relaxing agents in the presence of hypoxia-reoxygenation (H/R) was studied in an in vitro organ chamber setup. Sufentanil (10-7-10-4 mol/L) relaxed rat CA rings in endothelium-dependent and endothelium-independent manners. In endothelium-intact rings, preincubation of H/R-treated CAs with sufentanil (10-5 mol/L) significantly increased the acetylcholine response, but did not augment sodium nitroprusside-induced relaxation. Sufentanil-mediated potentiation of acetylcholine-induced relaxation was not affected by a nitric oxide synthase inhibitor or by intermediate- or small-conductance Ca2+-activated K+ channel blockers. However, potentiation was abolished by iberiotoxin (100 nmol/L), a selective inhibitor of large-conductance Ca2+-activated K+ channels, as well as Rp-cAMPS (30 µmol/L), a cyclic AMP-dependent protein kinase (PKA) inhibitor. Sufentanil induced endothelium-dependent and endothelium-independent relaxation and attenuated H/R-induced impairment of endothelium-dependent vasodilation in the rat CAs. The potentiating effect of sufentanil may involve activation of large-conductance Ca2+-activated K+ channels via cAMP-dependent mechanisms.


Assuntos
Vasos Coronários/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Sufentanil/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Vasos Coronários/fisiologia , Relação Dose-Resposta a Droga , Endotélio Vascular/fisiologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/fisiologia , Masculino , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Vasodilatação/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA