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1.
Food Chem ; 306: 125593, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31610327

RESUMO

The heat-induced aggregation of edible proteins has been regarded as one of the critical challenges for their application in protein-enriched beverages. Therefore, the formulation of thermal stable proteins to improve the stability of these beverages upon heating is highly desired. In this study, soy proteins (SPs) with enhanced heat stability were obtained by low-concentration-preheating (LCPH). Results from reheating of the above samples showed that pretreatment of SPs at low concentrations (≤1.0%, w/v) increased their resistance against aggregation. Additionally, when the suspensions of the particles were reheated at 10% (w/v) protein concentration, no gelation was found for samples prepared by LCPH, indicating collapsed protein-protein interactions, whereas gelled suspensions were obtained for native SPs and samples prepared by preheating at higher protein concentrations (≥2.0%, w/v). Furthermore, suspensions of particles prepared at lower protein concentration showed lower viscosities and higher flow behavior index values before and after reheat treatment. These findings highlighted that LCPH would provide fundamental information on the application of SPs in high protein beverages.

2.
Food Funct ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691684

RESUMO

Seafood provides a range of health benefits due to its nutritional and bioactive components. However, the bioactive peptides derived from Mytilus edulis proteins were seldom reported, especially their beneficial effects related to bone growth in vitro and in vivo. In this study, the water soluble protein from Mytilus edulis was isolated and the osteogenic activity of Mytilus edulis protein was determined in vivo. The protein from Mytilus edulis was subjected to simulated digestion in vitro, and the hydrolysate of different stages for osteogenic activity by osteoblast proliferation. It was found that the hydrolysate, derived from proteins hydrolyzed by pepsin for 2 h and trypsin for 3 h, showed high osteogenic activity, which induced an increase of 35.56 ± 2.92% in mouse-MC3T3-E1-preosteoblast-cell growth and the alkaline-phosphatase activity was 2.94 ± 0.10 mU, which was an increase of 19.78% compared with that of the control. Moreover, the molecular weight distribution of the peptides and the composition of the free amino acids were determined in order to evaluate the nutritional properties. These findings showed that the water soluble protein from Mytilus edulis could be used in functional food as a bioactive ingredient, which would be beneficial for bone growth and health.

3.
Food Chem Toxicol ; : 110881, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31622731

RESUMO

Dietary peptide has been of great interest because of its perspective in nutrition and health of human body. The aim of this study was to develop a dietary nutritional supplement exerting both antioxidant and anti-aging effects. Peptide, named as ERJ-CP, was prepared by mixing enzyme-treated royal jelly (ERJ) with collagen peptide (CP), showing stronger antioxidant activity in vitro. Drosophila was used as model animal to investigate anti-aging effect of ERJ-CP in vivo. ERJ-CP significantly prolonged the average life span of Drosophila treated with H2O2 and paraquat, reducing malondialdehyde (MDA) and protein carbonyl (PCO) levels in Drosophila. In addition, 3 mg/mL of ERJ-CP could prolong the lifespan of natural aging Drosophila by 11.16%. ERJ-CP could up-regulate the levels of total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and down-regulate the contents of MDA and PCO. Moreover, the intake of ERJ-CP increased the food consumption, weight gain and exercise capacity of Drosophila. The results showed that ERJ-CP played a protective role in both antioxidant and anti-aging effects on Drosophila, and the anti-aging effect may be achieved by alleviating oxidative damage. It suggests that ERJ-CP could be developed as a health-promoting ingredient with antioxidant and anti-aging effects for human body.

4.
Chemistry ; 25(61): 13972-13976, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31486561

RESUMO

2,4,6-Tri(4-pyridyl)-1,3,5-triazine (tpt) is a widely used ligand for functional coordination compounds. In this work, tpt has shown unprecedented photochromism in the crystalline state. Experimental and theoretical data has revealed that the photocoloration of tpt very likely originates from intramolecular charge separation and the formation of a triplet diradical product. This finding demonstrates a new simple, neutral photochromic molecule and endows the tpt molecule and related compounds with potential optical applications.

5.
Food Funct ; 10(10): 6473-6483, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31531441

RESUMO

The aroma of grilled eel is affected by three key processing steps: curing, steaming, and grilling. This study was aimed at the determination of the difference between the characteristic volatiles in each processing stage and their influence on the final aroma of grilled eel. A total of 92 volatile compounds were identified by purge and trap (P&T) combined with gas chromatography-mass spectrometry (GC-MS) throughout the processing. Alcohol, ketone, aromatic compounds and methylated compounds were the most important volatiles in the eel meat during processing. Pyrazine was generated gradually during the entire process, and 2,3-dimethylpyrazine was only found in the sample after grilling. Distinct odors among the raw and treated samples could be indirectly distinguished according to their volatile compounds, analyzed by heatmap. Together, these results indicate a relationship between the final aroma and the whole processing. The odor coding made from the odor activity value (OAV) could be as a reference benchmark for the grilled eel product.

6.
Food Funct ; 10(9): 5426-5435, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31402368

RESUMO

In this study, oyster (Crassostrea gigas) proteins were digested under in vitro gastrointestinal conditions to screen potential antithrombotic peptides. The sequences of the released peptides in the intestinal digestion phase were identified by ultra-performance liquid chromatography coupled to quadrupole time-of-flight MS (UPLC-Q-TOF-MS/MS). According to the antithrombotic activity analysis, the inhibitory ratio of oyster peptides showed an increasing trend, reaching up to 35.80% for a digestion period of 4 h. The APTT (activated partial thromboplastin time) and TT (thromboplastin time) were increased by oyster peptides for human serum in vitro. Oyster peptides showed a competitive inhibition effect on thrombin, based on Lineweaver-Burk plot analysis. Molecular docking between the antithrombotic peptides and thrombin (PDB: ) was conducted using Discovery Studio 2017. Potential inhibitors against thrombin and the mechanism of antithrombotic activity were predicted using the algorithm of CDOCKER. There are fourteen potential antithrombotic peptides, whose affinity with thrombin is higher than that of hirudin, as indicated by the "-CDOCKER energy" score (181.491). Peptide LSKEEIEEAKEV is similar in sequence to thrombin inhibitors. The binding sites of potential antithrombotic peptides against thrombin at the S1 pocket were compared with hirudin variant-2 (GDFEEIPEEYLQ). In addition, the peptides containing the RG/RGD sequence were identified, which can be hydrolyzed by thrombin as a substrate. Consequently, the oyster peptides released in simulated gastrointestinal digestion probably inhibit thrombin in two ways, not only as the inhibitor against the active site, but also as the substrate of thrombin. These results maybe be attributed to the potentially strong antithrombotic activity in the human digestive system.

7.
Food Funct ; 10(9): 5616-5625, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31432856

RESUMO

A novel osteogenic dodecapeptide peptide (PIE), IEELEEELEAER, was purified from the protein hydrolysate of blue mussels (Mytilus edulis). PIE was identified using a capillary electrophoresis electrospray ionization-quadrupole-time of flight mass spectrometer. PIE showed a good reduction in the bone loss in ovariectomized mice, and it also increased the bone mineral density of the ovariectomized mice. PIE has a high affinity with integrins (PDB: , ). There are 8 and 12 amino acid residues from PIE that interact with integrins and , respectively. PIE accelerates the transformation of G0/G1 phase cells into G2 M phase cells, which promotes the growth of osteoblasts. PIE (100 µg mL-1) can enhance alkaline phosphatase (ALP) activity by 26.48% compared with the control, and it also inhibits the growth of osteoclasts and tartrate resistant acid phosphatase (TRAP) activity. Therefore, PIE may contribute to preventing osteoporosis both in vitro and in vivo.

8.
Int J Biol Macromol ; 139: 1133-1140, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31419551

RESUMO

The aim of this experiment was to investigate the protective effects of polysaccharides of sea cucumber Acaudina leucoprocta (ALP) against hydrogen peroxide (H2O2) induced oxidative injury in RAW264.7 cells. Analysis of monosaccharide composition and structure of one fraction from ALP (ALPN) were analyzed by High Performance Liquid Chromatography (HPLC) and Fourier Transform Infrared Spectoscopy (FT-IR). The results showed that ALPN contain sulfate groups, which is sulfated polysaccharides. The results from MTT assay indicated that ALPN could markedly increase viability of cells compared with RAW264.7 cells exposed to H2O2. Moreover, ALPN significantly increased the levels of catalase (CAT), glutathione peroxidase (GSH-PX) and superoxide dismutase (SOD), decreased the production of malondialdehyde (MDA) and lactate dehydrogenase (LDH) in RAW264.7 cells. The data from RT-PCR showed that ALPN (300 µg/mL) could increase the gene expression levels of SOD1 and GPX1. ALPN could also observably increase the protein expression level of Nrf2 and decrease the protein expression level of Keap1 with western blot. Collectively, this study suggested that polysaccharides of sea cucumber Acaudina leucoprocta (ALP) could effectively protect RAW264.7 cells against H2O2-induced oxidative injury. This protection mechanism may be related to activation of the Nrf2/Keap1 signaling pathway.

9.
Food Funct ; 10(8): 5140-5151, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31368476

RESUMO

The development of binary protein networks featuring superior nutritional and rheological properties is an intriguing, as well as challenging, aspect in the food industry. In this study, a novel, self-assorted double protein network was constructed, which was achieved by simply heating soy protein (SP) and cod protein (CP) at 100 °C with different SP/CP ratios (5 : 0 to 0 : 5). Atomic force microscopy revealed that the heat-induced protein aggregate size increased with increasing CP ratio from 0 to 100%, which was accompanied by a significant increase in surface hydrophobicity and the content of disulfide bonds. Meanwhile, the ratio of non-network proteins in the gel network decreased significantly from 12.5 to 3.2% with the increase of the CP ratio from 0 to 100%. Concomitantly, the networks formed at a higher CP ratio were found to be less homogeneous and more porous with higher storage modulus. Interestingly, results from far-UV CD, near-UV CD, and fluorescence demonstrated that there were no interactions between SP and CP during thermal treatment, suggesting that the gel formed by mixed proteins was a self-sorted network. The study would advance the utilization of blended fish proteins and plant proteins toward tailor-made double networks that may find many applications in food and relevant areas.

10.
Ann Nucl Med ; 33(11): 806-812, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31388833

RESUMO

OBJECTIVE: As an important membrane protein, aquaglyceroporin involves liver glycerol metabolism, which can be used to stage liver fibrosis. In this study, we synthesized a novel molecular probe carbon-11-labeled AR ([11C]AR) with aminoglycerol (AR), and evaluated its preclinical performance for liver fibrosis diagnosis by positron emission tomography/computed tomography (PET/CT) imaging in vivo. METHODS: We developed a fully automatic synthesis procedure for the preparation of [11C]AR by radiolabeling glycerol analogue precursor AR with carbon-11. The liver uptake kinetics of [11C]AR was investigated using a rat model by the PET/CT scanner. The dynamic PET/CT scans were performed between the control group (n = 5) and experimental group (n = 25), which was divided into three subgroups (S1, S2 + S3, S4) based on the stages of liver fibrosis. The regions of interest (ROIs) of 20 pixels were drawn in the liver area on the reconstructed images. One-way analysis of variance and independent sample t test were used to analyze the statistical difference of the maximum standardized uptake value (SUVmax) among the groups at series of scanning time points (20 s, 60 s, 90 s, 150 s, 5 min, 10 min, 20 min and 25 min). RESULTS: The fully automatic synthesis of [11C]AR was successfully achieved with high synthesis efficiency (above 50%). The uptake of [11C]AR in progressive liver fibrosis tissues was significantly lower than that in healthy livers at all the imaging time points (P < 0.05), especially at early time points (before 10 min p.i.). A cut-off SUVmax value (1.1) at 150 s p.i. was set for discrimination progressive fibrosis from healthy liver. More experimental and healthy rats were tested with this new threshold to evaluate fibrosis situation. The sensitivity of detecting progressive fibrosis with [11C]AR was 100% in the second cohort. CONCLUSION: We demonstrated a new carbon-11-radiolabeled aminoglycerol PET/CT imaging probe [11C]AR for liver fibrosis diagnosis and staging, which may allow potential assessment of liver fibrosis stages in a rapid and noninvasive method.

11.
Cancer Med ; 8(13): 6049-6063, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31433128

RESUMO

An emerging body of evidence has promoted the understanding of the role of microRNAs (miRNAs) in tumorigenesis and progression, but the mediating function of miRNAs in nasopharyngeal carcinoma (NPC) development remains poorly elucidated. In this study, miR-449b-3p was downregulated in NPC specimens (P < .001) and cells (P < .05). Cytological and animal experiments provided evidence that miR-449b-3p inhibited NPC metastasis in vitro and in vivo. Disintegrin and metalloproteinase 17 (ADAM17) was revealed as a direct target of miR-449b-3p. Rescue experiments suggested that the downregulation of ADAM17 in the miR-449b-3p knockdown cells partially reversed the inhibition of cell invasion and migration. Luciferase reporter assay, chromatin immunoprecipitation assay, and Western blot analysis showed that ADAM17 could suppress the promoter activity and expression of miR-449b-3p by inducing NF-κB transcriptional activity. In conclusion, our study provided new insights into the underlying mechanism of the invasion and metastasis of NPC. The novel miR-449b-3p/ADAM17/NF-κB feedback loop could be a target for the clinical treatment of NPC.

12.
J Agric Food Chem ; 67(31): 8677-8688, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31293164

RESUMO

Reversed-phase ultrahigh-performance-liquid chromatography-mass spectrometry (UPLC-MS) is the typical method for the lipidomic analysis of most of biological samples, which was rarely used for the comprehensive lipidomic analysis of marine shellfish. Thus, a range of columns, modifiers, and resuspension solvents were evaluated using UPLC-electrospray ionization-quadrupole time-of-flight-MS to facilitate the ionization efficiency in both the positive and negative electrospray ionization (ESI(+)/(-)) modes for abalone lipids. Optimal lipidomic coverage was acquired with 10 mM ammonium formate in both ESI(+)/(-) modes. The selected resuspension solvents also influenced ionization efficiency through the matrix effect, and resuspension in methanol enhanced the signal intensities by reducing ion suppression. Because of the higher glycerophospholipid content in shellfish, bridged ethylene hybrid C8 columns showed clear advantages over charged surface hybrid C18 columns. A series of glycerophospholipids, lyso-glycerophospholipids, glycerolipids, and fatty acids in different shellfish can be annotated and semiquantified in one injection by the optimized method.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Lipídeos/química , Frutos do Mar/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Cromatografia Líquida de Alta Pressão/instrumentação , Ácidos Graxos/química , Glicerofosfolipídeos/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas em Tandem
13.
Ann Emerg Med ; 74(2): 185-250, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31331495
14.
J Food Biochem ; 43(4): e12801, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31353581

RESUMO

Alaska pollock frame is a kind of byproduct that was rich in protein, amino acids, and mineral elements. However, the unfavorite bitterness may probably be produced in enzymatic processes. In this study, the bitterness accounted from the hydrolysates prepared by neutral proteases, alkaline proteases, papain, flavourzyme, and animal proteases, was investigated. The hydrolysis conditions, amino acids composition, metal ion composition, molecular weight distribution, and peptide composition of the hydrolysates were detected to figure out the relationship between bitterness and compositions of the hydrolysates. The hydrolysate digested by alkaline protease has the highest bitterness intensity, and that amino acids composition, peptide composition, and molecular weight distribution had a significant influence on the bitterness degree. Hydrophobic amino acids and alkaline amino acids, such as leucine, isoleucine, lysine, and so on are likely to contribute to the bitterness and molecular weight distribution of peptides that affect bitterness is mainly lower than 3,000 Da. PRACTICAL APPLICATIONS: Fish bones would produce a bitter taste when reusing them by hydrolysis. Bitterness is one of unfavorable flavor as to consumers. The results of this study are of great significance for the further utilization of Alaska pollock frame. For products obtained from the hydrolysate of Alaska pollock frame, such as condiments and health care product the results of this study provide the processing technology of the lowest bitter hydrolysate, which can effectively improve the flavor and acceptability of the products.

15.
Cell Biol Int ; 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31329322

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF in the inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reduced body weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM-induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM-induced expression of α-smooth muscle actin at both the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor-ß1, interleukin-1ß, and tumor necrosis factor-α in the lungs of BLM-stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM-induced murine model.

16.
J Agric Food Chem ; 67(25): 7174-7182, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31240931

RESUMO

Intake of endocrine-disrupting chemicals (EDCs) by humans could disturb the metabolism of hormones, induce cancer, and damage the liver and other organs. Phthalate acid esters (PAEs) and alkylphenols (APs) are important EDCs and environmental contaminants. With the increasing use of plastics and nonionic surfactants worldwide, PAEs and APs have entered environmental water and accumulated in edible fish, which are finally consumed by humans. In this study, a coated direct inlet probe (CDIP) based on an atmospheric solid analysis probe, which can rapidly and simultaneously extract both PAEs and APs in fish, was developed. Twelve PAEs and APs were quantified by using a stable-isotope-labeled internal standard. Standard curves of the PAEs and APs having correlation coefficients of R2 ≥ 0.9837 were obtained. The limit of detection of the PAEs and APs was distributed from 0.01 to 40 ng g-1. The relative recovery of the method was 78-120% between low, medium, and high spiked levels. Combined with principal component analysis, PAE- and AP-contaminated Carassius auratus from different habitats could be identified. Multiple sample analysis mode allowed the extraction of up to 12 samples at once, and the total analysis time (including sample pretreatment, extraction, and analysis time) was less than 10 min per sample, which indicates that CDIP is useful for rapid quantitative analysis.


Assuntos
Ésteres/análise , Carpa Dourada , Ensaios de Triagem em Larga Escala/métodos , Fenóis/análise , Ácidos Ftálicos/análise , Animais , Disruptores Endócrinos/análise , Disruptores Endócrinos/isolamento & purificação , Ésteres/isolamento & purificação , Carpa Dourada/metabolismo , Ensaios de Triagem em Larga Escala/instrumentação , Limite de Detecção , Fenóis/isolamento & purificação , Ácidos Ftálicos/isolamento & purificação , Extração em Fase Sólida
17.
Acad Radiol ; 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31151899

RESUMO

OBJECTIVE: The aim of the present study was to use pharmacokinetic quantitative parameters with histogram and texture features on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to differentiate between the luminal A and luminal B molecular subtypes of breast cancer. METHODS: We retrospectively reviewed the data of 94 patients with histopathologically proven breast cancer. The pharmacokinetic quantitative parameters (Ktrans, Kep, and Ve) with their corresponding histogram and texture features based on preoperative DCE-MRI were obtained. The parameters were compared using the Mann-Whitney U-test between the luminal A and luminal B groups, the human epidermal growth factor receptor-2 (HER2)-positive luminal B and HER2-negative luminal B groups, and the lymph node metastasis (LNM)-positive and LNM-negative groups. Receiver operating characteristic curves were generated for parameters that presented significant between-group differences. RESULTS: The maximum values of Ktrans, Kep, and Ve, and the mean and 90th percentile values of Ve were significantly higher in the luminal B group than in the luminal A group. Among the texture features, only skewness of Ktrans significantly differed between the luminal A and B groups. All histogram features of Ktrans were higher in the HER2-positive luminal B group than in the HER2-negative luminal B group. However, no parameter differed between the LNM-positive and LNM-negative groups. CONCLUSION: Pharmacokinetic quantitative parameters with histogram and texture features obtained from DCE-MRI are associated with the molecular subtypes of breast cancer, and may serve as potential imaging biomarkers to differentiate between the luminal A and luminal B molecular subtypes.

18.
Int J Biol Macromol ; 135: 203-211, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31108145

RESUMO

The purpose of this study was to investigate structure of Hemp seed polysaccharide (HSP) and the protective effect of HSP from H2O2-induced oxidative damage in IPEC-1 cells and the possible mechanism of this protection. Analysis of monosaccharide composition and structure of two fractions HSP0 and HSP0.2 from polysaccharide of Hemp seed (HSPc) were analyzed by high performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy (FT-IR). The results showed that both HSP0 and HSP0.2 contain sulfate groups, which are sulfated polysaccharides. In IPEC-1 cells model, the release of LDH and MDA was significantly decreased, and the activities of SOD, GSH-Px and CAT were significantly increased in HSP0 and HSP0.2-treated group. HSP0.2 dramatically increased the gene expression of antioxidant enzymes and phase II detoxification enzymes measured by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (qRT-PCR). In addition, HSP0.2 up-regulated the expression level of intracellular transcription factor Nuclear factor erythroid-2-related factor 2 (Nrf2) and inhibited the level of Kelch-like ECH-associated protein 1 (Keap1) with Western blot analysis. Collectively, the present study suggested that HSP0.2 has the protective effect of IPEC-1 cells against H2O2-induecd oxidative stress. This protection mechanism may be related to activation of the Keap1/Nrf2 signaling pathway.

19.
Neurotherapeutics ; 16(3): 901-911, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31073979

RESUMO

Cerebral blood flow (CBF) reduction underlies unfavorable outcomes after subarachnoid hemorrhage (SAH). Transient receptor potential melastatin-4 (TRPM4) has a pivotal role in cerebral artery myogenic tone maintenance and CBF regulation under physiological conditions. However, the role of TRPM4 in CBF reduction after SAH is unclear. In this study, we aimed at testing whether TRPM4 would contribute to CBF reduction after SAH in vivo and determining underlying mechanisms. Rat SAH model was established by stereotaxic injection of autologous nonheparinized arterial blood at the suprasellar cistern. A TRPM4 blocker, 9-phenanthrol (9-Phe), was infused through an intraventricular catheter connected to a programmed subcutaneous pump to evaluate the contribution of TRPM4 to SAH outcomes. TRPM4 expression and translocation in cerebral artery myocytes were detected by immunoblotting. Macroscopic currents in cerebral artery myocytes were determined by whole-cell patch clamp. Myogenic tone of cerebral arteries was studied by pressurized myography. Cortical and global CBFs were measured via laser Doppler flowmetry and fluorescent microspheres, respectively. After SAH, TRPM4 translocation and macroscopic current density increased significantly. Furthermore, TRPM4 accounted for a greater proportion of myogenic tone after SAH, suggesting an upregulation of TRPM4 activity in response to SAH. Cortical and global CBFs were reduced after SAH, but were restored significantly by 9-Phe, implying that TRPM4 contributed to CBF reduction after SAH. Collectively, these discoveries show that increased TRPM4 activity has a pivotal role in CBF reduction after SAH, and provide a novel target for the management of cerebral perfusion dysfunction following SAH.

20.
Cryobiology ; 89: 68-75, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31082378

RESUMO

Vitrification of germinal vesicle (GV) stage oocytes has been shown to be closely associated with decreased rates of meiosis maturation and increased rates of aneuploidy. However, little is known about the effects of melatonin on these events in mice vitrified GV oocytes. In this study, the effects of melatonin on meiosis maturation potential and the incidence rate of aneuploidy in mouse vitrified oocytes were analyzed by supplementing in vitro maturation (IVM) solution with melatonin at different concentrations. This study, for the first time, showed that the mitochondrial heat production was markedly increased in vitrified oocytes (P < 0.05), which compromised the first polar body extrusion (PBE) of vitrified oocytes (73.3% vs. 85.1%, P < 0.05). However, 10-11 mol/L melatonin could significantly decrease mitochondrial heat production and ROS level (9.1 vs. 12.0 pixels, P < 0.05), meanwhile increase ATP level (1.1 vs. 0.88 pmol, P < 0.05) and mtDNA copies (107438 vs. 67869, P < 0.05), which rescued the abnormal chromosome alignment (32% vs. 69%, P < 0.05) and reduced the incidence of aneuploidy (15.6% vs. 38.5%, P < 0.05) in vitrified oocytes. The meiosis maturation ability of vitrified oocytes with melatonin supplementation was similar to that of fresh ones (83.4% vs. 85.1%, P > 0.05). Collectively, our data revealed that melatonin has a protective action against vitrification-induced injuries of oocytes meiosis maturation.

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