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1.
J Vasc Res ; 60(4): 234-244, 2023.
Article in English | MEDLINE | ID: mdl-37643584

ABSTRACT

INTRODUCTION: Culturing cerebrovascular smooth muscle cells (CVSMCs) in vitro can provide a model for studying many cerebrovascular diseases. This study describes a convenient and efficient method to obtain mouse CVSMCs by enzyme digestion. METHODS: Mouse circle of Willis was isolated, digested, and cultured with platelet-derived growth factor-BB (PDGF-BB) to promote CVSMC growth, and CVSMCs were identified by morphology, immunofluorescence analysis, and flow cytometry. The effect of PDGF-BB on vascular smooth muscle cell (VSMC) proliferation was evaluated by cell counting kit (CCK)-8 assay, morphological observations, Western blotting, and flow cytometry. RESULTS: CVSMCs cultured in a PDGF-BB-free culture medium had a typical peak-to-valley growth pattern after approximately 14 days. Immunofluorescence staining and flow cytometry detected strong positive expression of the cell type-specific markers alpha-smooth muscle actin (α-SMA), smooth muscle myosin heavy chain 11 (SMMHC), smooth muscle protein 22 (SM22), calponin, and desmin. In the CCK-8 assay and Western blotting, cells incubated with PDGF-BB had significantly enhanced proliferation compared to those without PDGF-BB. CONCLUSION: We obtained highly purified VSMCs from the mouse circle of Willis using simple methods, providing experimental materials for studying the pathogenesis and treatment of neurovascular diseases in vitro. Moreover, the experimental efficiency improved with PDGF-BB, shortening the cell cultivation period.


Subject(s)
Circle of Willis , Muscle, Smooth, Vascular , Animals , Mice , Becaplermin/pharmacology , Becaplermin/metabolism , Proto-Oncogene Proteins c-sis/pharmacology , Proto-Oncogene Proteins c-sis/metabolism , Muscle, Smooth, Vascular/metabolism , Cells, Cultured , Cell Proliferation , Myocytes, Smooth Muscle/metabolism , Cell Movement
2.
Cardiovasc Diabetol ; 22(1): 216, 2023 08 17.
Article in English | MEDLINE | ID: mdl-37592255

ABSTRACT

BACKGROUND: Myocardial microvascular injury is the key event in early diabetic heart disease. The injury of myocardial microvascular endothelial cells (CMECs) is the main cause and trigger of myocardial microvascular disease. Mitochondrial calcium homeostasis plays an important role in maintaining the normal function, survival and death of endothelial cells. Considering that mitochondrial calcium uptake 1 (MICU1) is a key molecule in mitochondrial calcium regulation, this study aimed to investigate the role of MICU1 in CMECs and explore its underlying mechanisms. METHODS: To examine the role of endothelial MICU1 in diabetic cardiomyopathy (DCM), we used endothelial-specific MICU1ecKO mice to establish a diabetic mouse model and evaluate the cardiac function. In addition, MICU1 overexpression was conducted by injecting adeno-associated virus 9 carrying MICU1 (AAV9-MICU1). Transcriptome sequencing technology was used to explore underlying molecular mechanisms. RESULTS: Here, we found that MICU1 expression is decreased in CMECs of diabetic mice. Moreover, we demonstrated that endothelial cell MICU1 knockout exacerbated the levels of cardiac hypertrophy and interstitial myocardial fibrosis and led to a further reduction in left ventricular function in diabetic mice. Notably, we found that AAV9-MICU1 specifically upregulated the expression of MICU1 in CMECs of diabetic mice, which inhibited nitrification stress, inflammatory reaction, and apoptosis of the CMECs, ameliorated myocardial hypertrophy and fibrosis, and promoted cardiac function. Further mechanistic analysis suggested that MICU1 deficiency result in excessive mitochondrial calcium uptake and homeostasis imbalance which caused nitrification stress-induced endothelial damage and inflammation that disrupted myocardial microvascular endothelial barrier function and ultimately promoted DCM progression. CONCLUSIONS: Our findings demonstrate that MICU1 expression was downregulated in the CMECs of diabetic mice. Overexpression of endothelial MICU1 reduced nitrification stress induced apoptosis and inflammation by inhibiting mitochondrial calcium uptake, which improved myocardial microvascular function and inhibited DCM progression. Our findings suggest that endothelial MICU1 is a molecular intervention target for the potential treatment of DCM.


Subject(s)
Calcium-Binding Proteins , Diabetes Mellitus, Experimental , Diabetic Cardiomyopathies , Mitochondrial Membrane Transport Proteins , Animals , Mice , Calcium , Dependovirus , Diabetic Cardiomyopathies/genetics , Diabetic Cardiomyopathies/prevention & control , Endothelial Cells , Inflammation
3.
ACS Nano ; 17(13): 12072-12086, 2023 07 11.
Article in English | MEDLINE | ID: mdl-37363813

ABSTRACT

Tissue engineering raised a high requirement to control cell distribution in defined materials and structures. In "ink"-based bioprintings, such as 3D printing and photolithography, cells were associated with inks for spatial orientation; the conditions suitable for one ink are hard to apply on other inks, which increases the obstacle in their universalization. The Magneto-Archimedes effect based (Mag-Arch) strategy can modulate cell locomotion directly without impelling inks. In a paramagnetic medium, cells were repelled from high magnetic strength zones due to their innate diamagnetism, which is independent of substrate properties. However, Mag-Arch has not been developed into a powerful bioprinting strategy as its precision, complexity, and throughput are limited by magnetic field distribution. By controlling the paramagnetic reagent concentration in the medium and the gaps between magnets, which decide the cell repelling scope of magnets, we created simultaneously more than a hundred micrometer scale identical assemblies into designed patterns (such as alphabets) with single/multiple cell types. Cell patterning models for cell migration and immune cell adhesion studies were conveniently created by Mag-Arch. As a proof of concept, we patterned a tumor/endothelial coculture model within a covered microfluidic channel to mimic epithelial-mesenchymal transition (EMT) under shear stress in a cancer pathological environment, which gave a potential solution to pattern multiple cell types in a confined space without any premodification. Overall, our Mag-Arch patterning presents an alternative strategy for the biofabrication and biohybrid assembly of cells with biomaterials featured in controlled distribution and organization, which can be broadly employed in tissue engineering, regenerative medicine, and cell biology research.


Subject(s)
Cell Culture Techniques , Ink , Tissue Engineering/methods , Cell Communication , Microfluidic Analytical Techniques , Coculture Techniques , Cell Movement , Magnetics , Humans , Cell Culture Techniques/methods
4.
Sci Rep ; 13(1): 3681, 2023 03 06.
Article in English | MEDLINE | ID: mdl-36878975

ABSTRACT

We evaluated the effect of acute hypobaric hypoxia (AHH) on the hippocampal region of the brain in early-stage spontaneously hypertensive male rats. The rats were classified into a control (ground level; ~ 400 m altitude) group and an AHH experimental group placed in an animal hypobaric chamber at a simulated altitude of 5500 m for 24 h. RNA-Seq analysis of the brains and hippocampi showed that differentially expressed genes (DEGs) were primarily associated with ossification, fibrillar collagen trimer, and platelet-derived growth factor binding. The DEGs were classified into functional categories including general function prediction, translation, ribosomal structure and biogenesis, replication, recombination, and repair. Pathway enrichment analysis revealed that the DEGs were primarily associated with relaxin signaling, PI3K-Akt signaling, and amoebiasis pathways. Protein-protein interaction network analysis indicated that 48 DEGs were involved in both inflammation and energy metabolism. Further, we performed validation experiments to show that nine DEGs were closely associated with inflammation and energy metabolism, of which two (Vegfa and Angpt2) and seven (Acta2, Nfkbia, Col1a1, Edn1, Itga1, Ngfr, and Sgk1) genes showed up and downregulated expression, respectively. Collectively, these results indicated that inflammation and energy metabolism-associated gene expression in the hippocampus was altered in early-stage hypertension upon AHH exposure.


Subject(s)
Phosphatidylinositol 3-Kinases , Transcriptome , Male , Rats , Animals , Rats, Inbred SHR , Energy Metabolism , Hippocampus , Inflammation/genetics , Hypoxia/genetics
5.
Aerosp Med Hum Perform ; 93(6): 487-492, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35729759

ABSTRACT

BACKGROUND: Modafinil, as a wake-promoting agent, is commonly used to relieve fatigue during military operations. However, there is a lack of clarity regarding the effects of modafinil on the equilibrium and vestibular organs, especially when prescribing this drug to flight crewmembers. The objective of this study was to evaluate the equilibrium- and vestibular-related safety effects of modafinil.METHODS: In a randomized, double-blind, placebo-controlled, crossover study, 10 healthy male volunteers received a single 200-mg oral dose of modafinil or placebo. Equilibrium and vestibular functions were assessed 2 h after oral administration by the sensory organization test (SOT), adaptation test (ADT), and video head impulse test (v-HIT).RESULTS: There was no change in the equilibrium scores of the six SOT conditions or the composite scores between the modafinil and placebo groups. Statistically significant differences were not observed for the sway energy score (SES) in the toe-down test. In the toe-up test, the SES decreased by 16.7% in the modafinil group relative to the placebo group in trial 2, while the differences in other trials were not statistically significant. In the v-HIT, there was no significant difference in the gain of each semicircular canal between the two groups.DISCUSSION: A single 200-mg dose of modafinil did not cause any impairment to vestibular function, equilibrium ability, or adaptive balance response; in fact, modafinil might have a positive effect on adaptation function in healthy volunteers. These findings preliminarily suggest that there is no hidden risk of vestibular dysfunction among aviation employees using modafinil.Liu F, Zhang M, Chen T, Zhai L, Zhang Z, Xue J. Equilibrium and vestibular safety of modafinil in healthy volunteers. Aerosp Med Hum Perform. 2022; 93(6):487-492.


Subject(s)
Central Nervous System Stimulants , Vestibule, Labyrinth , Benzhydryl Compounds/adverse effects , Central Nervous System Stimulants/pharmacology , Cross-Over Studies , Double-Blind Method , Healthy Volunteers , Humans , Male , Modafinil/adverse effects
6.
BMC Cancer ; 21(1): 318, 2021 Mar 25.
Article in English | MEDLINE | ID: mdl-33765973

ABSTRACT

BACKGROUND: Icaritin, an active ingredient of the Chinese herb Epimedium, plays an anti-tumor role in liver cancer by inhibiting the proliferation of hepatocellular cells and promoting their apoptosis. In China, phase II and a large phase III clinical trial of icaritin reagent for the treatment of hepatocellular cancer is under-going, but the specific mechanism of icaritin action was unclear. Alpha-fetoprotein (AFP), an oncofetal protein, produced in the healthy fetal liver and yolk sac. Intracellular AFP promoted cellular proliferation and inhibited cellular apoptosis in hepatocellular carcinoma (HCC). The study was aimed to investigate the effect of icaritin on HCC through p53/AFP pathway. METHODS: Real-time RT PCR and western blot were used to detect p53 and AFP expression levels in HCC cells treated with icaritin. The mechanism of icaritin affecting p53 expression was verified by ubiquitination experiment, and the binding activity of icaritin on p53 in AFP promoter region was verified by luciferase experiment. EdU, MTT and flow cytometry were used to determine whether icaritin affected HCC cellular proliferation and apoptosis through p53/ AFP pathway. Expression levels of p53 and AFP in xenograft mouse model were determined by western blotting. RESULTS: Our results showed icaritin inhibited AFP expression at mRNA and protein level. AFP was also identified as the target gene of the p53 transcription factor. Icaritin abrogated murine double minute (Mdm) 2-mediated p53 ubiquitination degradation to improve the stability of p53. Up-regulated p53 protein levels then transcriptionally inhibited the AFP promoter. Icaritin-mediated decrease of AFP through Mdm2/p53 pathways inhibited HCC cellular proliferation and promoted HCC cellular apoptosis. CONCLUSION: Our findings revealed the mechanism of icaritin in promoting apoptosis and inhibiting proliferation in liver cancer cells. The regulatory mechanism of icaritin in AFP protein down-regulation provides a theoretical and experimental basis for further research into new drugs for the treatment of liver cancer.


Subject(s)
Carcinoma, Hepatocellular/drug therapy , Flavonoids/pharmacology , Liver Neoplasms/drug therapy , alpha-Fetoproteins/genetics , Animals , Apoptosis/drug effects , Apoptosis/genetics , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Cell Proliferation/drug effects , Cell Proliferation/genetics , Down-Regulation , Flavonoids/therapeutic use , Gene Expression Regulation, Neoplastic/drug effects , Hep G2 Cells , Humans , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Male , Mice , Signal Transduction/drug effects , Signal Transduction/genetics , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor Assays , alpha-Fetoproteins/metabolism
7.
Sci Total Environ ; 777: 146081, 2021 Jul 10.
Article in English | MEDLINE | ID: mdl-33677293

ABSTRACT

Direct ingestion of urban sediment particles represents an important pathway of human exposure to heavy metals. The effect of particle sizes on metal bioaccessibilities in human digestive system has not been fully understood. In this study, an in-vitro simulation experiment (PBET), along with environmental magnetic measurements, is conducted on two urban sediments (street dusts and beach sediments) with different particle sizes (Φ31.1 ± 7.36 µm for street dusts and Φ134 ± 21.1 µm for beach sediments) for the purposes of assessing the particle size effect on metal bioaccessibilities in simulated gastric and intestinal tracts, and exploring the environmental magnetism response to different digestion processes. For street dusts, the bioaccessibilities of heavy metals decrease significantly from gastric (12.1 (Cu) ~ 39.9% (Pb)) to intestinal phase (0.41 (Pb) ~ 2.08% (Cd)) due to an increase in digestive juice pH. However, for beach sediments, the metal bioaccessibilities in the intestinal phase is similar to, or even higher than, those in the gastric phase. These demonstrate that clay minerals and Fe/Mn oxides concentrated in fine particles play an important role in adsorbing and fixating heavy metals in neutral intestinal tract. Compared with those of the original samples, the χfd% values of the PBET treated street dusts decrease significantly, and the decreasing extents (Δχfd%) are positively correlated with the concentrations of the PBET extracted Fe (p < 0.05). However, a reverse trend is observed for the beach sediment samples. These findings suggest that the magnetic minerals formed during the digestion process might affect the metal bioaccessibilities in gastrointestinal tract.


Subject(s)
Dust , Metals, Heavy , Cities , Dust/analysis , Environmental Monitoring , Humans , Metals, Heavy/analysis , Particle Size , Risk Assessment
8.
Cancer Lett ; 471: 12-26, 2020 02 28.
Article in English | MEDLINE | ID: mdl-31811908

ABSTRACT

Alpha-fetoprotein (AFP) is a well-established biomarker for hepatocellular carcinoma (HCC). Here, we investigated the acetylation state of AFP in vivo. AFP acetylation was regulated by the acetyltransferase CBP and the deacetylase SIRT1. Acetylation of AFP at lysines 194, 211, and 242 increased the stability of AFP protein by decreasing its ubiquitination and proteasomal degradation. AFP acetylation promoted its oncogenic role by blocking binding to the phosphatase PTEN and the pro-apoptotic protein caspase-3, which increased signaling for proliferation, migration, and invasion and decreased apoptosis. High levels of acetylated AFP in HCC tissues were associated with HBV infection and correlated with poor prognosis and decreased patient survival. In HCC cells, hepatitis B virus X protein (HBx) and palmitic acid (PA) increased the level of acetylated AFP by disrupting SIRT1-mediated deacetylation. AFP acetylation plays an important role in HCC progression and provides a new potential prognostic marker and therapeutic target for HCC.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/metabolism , alpha-Fetoproteins/metabolism , Acetylation/drug effects , Amino Acid Sequence , Animals , Apoptosis/physiology , CREB-Binding Protein/metabolism , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/virology , Cell Movement/physiology , Cell Proliferation/physiology , HEK293 Cells , Hep G2 Cells , Hepatitis B, Chronic/metabolism , Humans , Liver Neoplasms/drug therapy , Liver Neoplasms/virology , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Invasiveness , Palmitic Acid/pharmacology , Prognosis , Sirtuin 1/metabolism , Trans-Activators/biosynthesis , Trans-Activators/genetics , Trans-Activators/metabolism , Transfection , Viral Regulatory and Accessory Proteins/biosynthesis , Viral Regulatory and Accessory Proteins/genetics , Viral Regulatory and Accessory Proteins/metabolism
9.
BMC Ophthalmol ; 19(1): 112, 2019 May 16.
Article in English | MEDLINE | ID: mdl-31096936

ABSTRACT

BACKGROUND: Oxidative stress (OS) is an essential factor in the pathogenesis of branch retinal vein occlusion (BRVO). Studies have demonstrated the role of hydrogen gas in the regulation of OS. This study was designed to evaluate the efficacy of hydrogen gas on the BRVO rat model. METHODS: Twenty-four BRVO rats were randomly divided into two groups: the hydrogen gas (H) group (42% H2, 21% O2, 37% N2) and the model (M) group (21% O2, 79% N2). Rats in the H group inhaled hydrogen gas for 8 h every day up to 30 d post-occlusion. Twelve age-matched healthy rats served as the control (C) group. Retinal function and morphology were detected at 1, 7, 14 and 30 d post-occlusion. Furthermore, the expression of vascular endothelial growth factor (VEGF-α) was detected by immunofluorescent staining. RESULTS: Full-field electroretinography (ffERG) revealed that the amplitude of the b-wave (dark-adaptation 3.0 response), the amplitude of the OPs2 wave and the light-adapted flicker response in the H group were all higher than those in the M group at 7 d post-occlusion (all p < 0.05). The reopen time of occlusive retinal vessels in the H group was 2.235 ± 1.128 d, which was shorter than that in the M group (4.234 ± 2.236 d, p < 0.05). The rats in the H group had a thinner IPL + GCL + NFL and an increased total retina compared with those in the M group at 3 d post-occlusion (p < 0.05), while the rats in the H group had a thicker INL, IPL + GCL + NFL and total retina compared with those at 7, 14 and 30 d post-occlusion (p < 0.05). Moreover, the flow velocity of ear vein blood was increased in the H group compared with that in the M group (p < 0.05). The expression of VEGF-α in the H group was dramatically decreased compared with that in the M group at 1, 7 and 14 d post-occlusion (p < 0.05), while the expression kept in similar level at 30 d post-occlusion (p > 0.05). CONCLUSIONS: Our findings demonstrate that inhalation of hydrogen gas could alleviate retinal oedema, shorten reopen time and improve retinal function, and the potential mechanism might be related to a decrease in VEGF-α expression.


Subject(s)
Hydrogen/pharmacology , Retina/drug effects , Retinal Vein Occlusion/metabolism , Vascular Endothelial Growth Factor A/metabolism , Animals , Disease Models, Animal , Electroretinography , Male , Oxidative Stress/drug effects , Rats , Rats, Sprague-Dawley , Retina/metabolism , Retina/physiopathology , Retinal Vein Occlusion/physiopathology
10.
Oncogene ; 38(24): 4835-4855, 2019 06.
Article in English | MEDLINE | ID: mdl-30816344

ABSTRACT

Genome instability is a common feature of tumor cells, and the persistent presence of genome instability is a potential mechanism of tumorigenesis. The E3 ubiquitin ligase MDM2 is intimately involved in genome instability, but its mechanisms are unclear. Our data demonstrated that the transcription factor HBP1 is a target of MDM2. MDM2 facilitates HBP1 proteasomal degradation by ubiquitinating HBP1, regardless of p53 status, thus attenuating the transcriptional inhibition of HBP1 in the expression of its target genes, such as the DNA methyltransferase DNMT1 and histone methyltransferase EZH2, which results in global DNA hypermethylation and histone hypermethylation and ultimately genome instability. The repression of HBP1 by MDM2 finally promotes cell growth and tumorigenesis. Next, we thoroughly explored the regulatory mechanism of the MDM2/HBP1 axis in DNA damage repair following ionizing radiation. Our data indicated that MDM2 overexpression-mediated repression of HBP1 delays DNA damage repair and causes cell death in a p53-independent manner. This investigation elucidated the mechanism of how MDM2 promotes genome instability and enhances tumorigenesis in the absence of p53, thus providing a theoretical and experimental basis for targeting MDM2 as a cancer therapy.


Subject(s)
Genomic Instability , High Mobility Group Proteins/metabolism , Proto-Oncogene Proteins c-mdm2/physiology , Repressor Proteins/metabolism , Ubiquitination , Animals , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Gene Expression Regulation, Neoplastic , Genomic Instability/genetics , HEK293 Cells , HeLa Cells , Humans , MCF-7 Cells , Male , Mice , Mice, Nude , Protein Processing, Post-Translational/genetics , Proto-Oncogene Proteins c-mdm2/metabolism , Tumor Suppressor Protein p53/physiology , Ubiquitination/genetics
11.
Cell Physiol Biochem ; 47(5): 1883-1897, 2018.
Article in English | MEDLINE | ID: mdl-29961073

ABSTRACT

BACKGROUND/AIMS: Our laboratory discovered a Kunming mouse with enormous electroretinogram (ERG) defects. Its auditory brainstem response (ABR) threshold was significantly elevated and closely resembled the features of Usher syndrome (USH). This study sought to cross these USH-like mice (named KMush/ush mice) with CBA/CaJ mice to establish recombinant inbred strains and identify their phenotypes and genotypes. METHODS: KMush/ush mice were crossed with CBA/CaJ mice to establish inbred strains by sibling mating. ERG, ABR, ocular fundus morphology, histological examinations of the retina and inner ear, quantitative real-time polymerase chain reaction, western blotting, and exon sequencing were performed to assess the phenotypes and genotypes of the offspring strains. RESULTS: The F1 hybrids from crossing KMush/ush and CBA/CaJ mice had normal ERG and ABR responses. The F2 offspring from intercrossing the F1 mice showed a segregation of the retinitis pigmentosa (RP) and hearing loss phenotypes. The CBA-1ush/ush mice had an RP phenotype that was characterized by a vanished ERG waveform and loss of the outer nuclear layer. Their Pde6b gene had a nonsense mutation that resulted in the failure of protein production in western blotting. However, the ABR threshold of this strain of mice was normal. The CBA-2ush/ush mice had normal retinal function and architecture. Their ABR threshold was increased, with a dramatic degeneration of the stereocilia bundles in the outer hair cells of the inner ear. Whole exome sequencing and exon sequencing revealed a deletion of one base pair in exon 31 of the Adgrv1 gene, which would result in the premature termination of protein encoding. The level of Adgrv1 mRNA was reduced in the CBA-2ush/ush mice. The CBA-3ush/ush mice had phenotypes of RP, elevated ABR threshold, and degeneration of the stereocilia bundles in the outer hair cells. They were closely associated with the nonsense mutations of Pde6b and Adgrv1, respectively. CONCLUSION: We isolated a mouse strain with hearing loss from inbred mice with retinal degeneration and established it as a recombinant inbred strain with a spontaneous mutation in Adgrv1, the human Usher syndrome 2C gene. The retinal degeneration was cause by a mutation in Pde6b, while the hearing loss was caused by a mutation in Adgrv1.


Subject(s)
Exons , Inbreeding , Receptors, G-Protein-Coupled/genetics , Usher Syndromes/genetics , Animals , Disease Models, Animal , Mice , Mutation , Usher Syndromes/pathology
12.
J Biol Chem ; 292(20): 8207-8222, 2017 05 19.
Article in English | MEDLINE | ID: mdl-28348080

ABSTRACT

Oxidative stress can induce cell dysfunction and lead to a broad range of degenerative alterations, including carcinogenesis, aging, and other oxidative stress-related conditions. To avoid undergoing carcinogenesis in response to oxidative stress, cells trigger a succession of checkpoint responses, including premature senescence and apoptosis. Increasing evidence indicates that H2O2, an important cause of oxidative stress, functions as an important physiological regulator of intracellular signaling pathways that participate in regulation of cell premature senescence and apoptosis. However, the precise mechanisms underlying this process remain to be studied extensively. In this study, we describe the importance of Pim-1 kinase in this checkpoint response to oxidative stress. Pim-1 binds to and phosphorylates the transcription factor high mobility group box transcription factor 1 (HBP1), activating it. H2O2 enhances the interaction between Pim-1 and HBP1 and promotes HBP1 accumulation. In turn, HBP1 rapidly and selectively up-regulates Pim-1 expression in H2O2-stimulated cells, thereby creating a Pim-1-HBP1 positive feedback loop that regulates H2O2-induced premature senescence and apoptosis. Furthermore, the Pim-1-HBP1 positive feedback loop exerts its effect by regulating the senescence markers DNMT1 and p16 and the apoptosis marker Bax. The Pim-1-HBP1 axis thus constitutes a novel checkpoint pathway critical for the inhibition of tumorigenesis.


Subject(s)
Apoptosis/drug effects , Cellular Senescence/drug effects , Gene Expression Regulation, Enzymologic/drug effects , High Mobility Group Proteins/metabolism , Hydrogen Peroxide/pharmacology , Proto-Oncogene Proteins c-pim-1/biosynthesis , Repressor Proteins/metabolism , Up-Regulation/drug effects , Apoptosis/genetics , Cell Cycle Checkpoints/drug effects , Cell Cycle Checkpoints/genetics , Cellular Senescence/genetics , Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclin-Dependent Kinase Inhibitor p16/metabolism , DNA (Cytosine-5-)-Methyltransferase 1 , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA (Cytosine-5-)-Methyltransferases/metabolism , HeLa Cells , High Mobility Group Proteins/genetics , Humans , Oxidative Stress/drug effects , Oxidative Stress/genetics , Proto-Oncogene Proteins c-pim-1/genetics , Repressor Proteins/genetics
13.
Exp Eye Res ; 148: 65-73, 2016 07.
Article in English | MEDLINE | ID: mdl-27215478

ABSTRACT

The N-methyl-N-nitrosourea (MNU)-treated rat is typically used as an animal model of chemically-induced retinitis pigmentosa (RP). Reactive oxygen species (ROS) have been recognized as the crucial contributor to the retinal photoreceptor apoptosis seen in MNU-treated rats. In the present study, we explored the therapeutic effects of hydrogen-rich saline (HRS), a selective ROS scavenger, on MNU-induced photoreceptor degeneration. Intraperitoneal (IP) administration of HRS ameliorated MNU-induced photoreceptor degeneration in terms of morphology and function: Sharply decreased thickness of the retinal outer nuclear layer (ONL) and flattened photopic and scotopic electroretinogram (ERG) waveforms, typically seen in response to MNU treatment, were substantially rescued in rats cotreated with MNU and HRS (MNU + HRS). Moreover, the terminal deoxyuridine triphosphate nick-end labeling (TUNEL) assay revealed a smaller number of apoptotic photoreceptors in the MNU + HRS group compared that in the MNU group. Compared to MNU-treated rats, retinal malondialdehyde (MDA) content in MNU + HRS rats significantly decreased while superoxide dismutase (SOD) activity significantly increased. Morphological and multi-electrode array (MEA) analyses revealed more efficient preservation of the architecture and field potential waveforms in particularly the peripheral regions of the retinas within the MNU + HRS group, compared to that in the MNU group. However, this enhanced protection of structure and function in the peripheral retina is unlikely the result of site-dependent variation in the efficacy of HRS; rather, it is most likely due to reduced susceptibility of peripheral photoreceptors to MNU-induced degeneration. Inner retinal neuron function in the MNU + HRS rats was better preserved, with fewer apoptotic photoreceptors in the ONL. Collectively, these results support the rationale for future clinical evaluation of HRS as a therapeutic agent for human RP.


Subject(s)
Hydrogen/pharmacology , Hypertonic Solutions/pharmacology , Methylnitrosourea/toxicity , Photoreceptor Cells, Vertebrate/drug effects , Retinal Degeneration/drug therapy , Analysis of Variance , Animals , Apoptosis/drug effects , Disease Models, Animal , Electroretinography , Hypertonic Solutions/chemistry , In Situ Nick-End Labeling , Injections, Intraperitoneal , Malondialdehyde/metabolism , Oxidative Stress/physiology , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Retina/metabolism , Retinal Degeneration/chemically induced , Retinal Degeneration/physiopathology , Retinal Ganglion Cells/physiology , Superoxide Dismutase/metabolism
14.
PLoS One ; 11(5): e0155619, 2016.
Article in English | MEDLINE | ID: mdl-27186975

ABSTRACT

Usher syndrome is a group of autosomal recessive diseases characterized by congenital deafness and retinitis pigmentosa. In a mouse model for Usher syndrome, KMush/ush, discovered in our laboratory, we measured the phenotypes, characterized the architecture and morphology of the retina, and quantified the level of expression of pde6b and ush2a between postnatal (P) days 7, and 56. Electroretinograms and auditory brainstem response were used to measure visual and auditory phenotypes. Fundus photography and light microscopy were used to measure the architecture and morphology of the retina. Quantitative real-time PCR was used to measure the expression levels of mRNA. KMush/ush mice had low amplitudes and no obvious waveforms of Electroretinograms after P14 compared with controls. Thresholds of auditory brainstem response in our model were higher than those of controls after P14. By P21, the retinal vessels of KMush/ush mice were attenuated and their optic discs had a waxy pallor. The retinas of KMush/ush mice atrophied and the choroidal vessels were clearly visible. Notably, the architecture of each retinal layer was not different as compared with control mice at P7, while the outer nuclear layer (ONL) and other retinal layers of KMush/ush mice were attenuated significantly between P14 and P21. ONL cells were barely seen in KMush/ush mice at P56. As compared with control mice, the expression of pde6b and ush2a in KMush/ush mice declined significantly after P7. This study is a first step toward characterizing the progression of disease in our mouse model. Future studies using this model may provide insights about the etiology of the disease and the relationships between genotypes and phenotypes providing a valuable resource that could contribute to the foundation of knowledge necessary to develop therapies to prevent the retinal degeneration in patients with Usher Syndrome.


Subject(s)
Deafness/physiopathology , Retinal Degeneration/physiopathology , Usher Syndromes/physiopathology , Animals , Cyclic Nucleotide Phosphodiesterases, Type 6/genetics , Deafness/genetics , Disease Models, Animal , Electroretinography , Evoked Potentials, Auditory, Brain Stem , Extracellular Matrix Proteins/genetics , Female , Fundus Oculi , Male , Mice , Retina/pathology , Retinal Degeneration/genetics , Retinal Degeneration/pathology , Usher Syndromes/genetics , Usher Syndromes/pathology
15.
J Biol Chem ; 291(24): 12688-12705, 2016 Jun 10.
Article in English | MEDLINE | ID: mdl-27129219

ABSTRACT

The activity of the CDK inhibitor p21 is associated with diverse biological activities, including cell proliferation, senescence, and tumorigenesis. However, the mechanisms governing transcription of p21 need to be extensively studied. In this study, we demonstrate that the high-mobility group box-containing protein 1 (HBP1) transcription factor is a novel activator of p21 that works as part of a complex mechanism during senescence and tumorigenesis. We found that HBP1 activates the p21 gene through enhancing p53 stability by inhibiting Mdm2-mediated ubiquitination of p53, a well known positive regulator of p21. HBP1 was also found to enhance p21 transcription by inhibiting Wnt/ß-catenin signaling. We identified histone methyltransferase EZH2, the catalytic subunit of polycomb repressive complex 2, as a target of Wnt/ß-catenin signaling. HBP1-mediated repression of EZH2 through Wnt/ß-catenin signaling decreased the level of trimethylation of histone H3 at lysine 27 of overall and specific histone on the p21 promoter, resulting in p21 transactivation. Although intricate, the reciprocal partnership of HBP1 and p21 has exceptional importance. HBP1-mediated elevation of p21 through the Mdm2/p53 and TCF4/EZH2 pathways contributes to both cellular senescence and tumor inhibition. Together, our results suggest that the HBP1 transcription factor orchestrates a complex regulation of key genes during cellular senescence and tumorigenesis with an impact on protein ubiquitination and overall histone methylation state.


Subject(s)
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Cyclin-Dependent Kinase Inhibitor p21/genetics , Enhancer of Zeste Homolog 2 Protein/genetics , High Mobility Group Proteins/genetics , Proto-Oncogene Proteins c-mdm2/genetics , Repressor Proteins/genetics , Transcription Factors/genetics , Tumor Suppressor Protein p53/genetics , A549 Cells , Animals , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Blotting, Western , Carcinogenesis/genetics , Cell Line , Cell Line, Tumor , Cell Survival/genetics , Cellular Senescence/genetics , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Enhancer of Zeste Homolog 2 Protein/metabolism , Female , Gene Expression Regulation , HEK293 Cells , Hep G2 Cells , High Mobility Group Proteins/metabolism , Humans , Mice, Nude , Protein Binding , Proto-Oncogene Proteins c-mdm2/metabolism , RNA Interference , Repressor Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/genetics , Transcription Factor 4 , Transcription Factors/metabolism , Transplantation, Heterologous , Tumor Suppressor Protein p53/metabolism
16.
Langmuir ; 32(9): 2259-66, 2016 Mar 08.
Article in English | MEDLINE | ID: mdl-26886176

ABSTRACT

Here, we demonstrated that, when the precipitation process of polyamide-6 (PA6) solution happens in cylindrical channels of an anodized aluminum oxide membrane (AAO), interface interactions between a solid surface, solvent, non-solvent, and PA6 will influence the obtained polymer nanostructures, resulting in complex morphologies, increased surface area, and crystallization changes. With the enhancing interaction of PA6 and the AAO surface, the morphology of PA6 nanostructures changes from solid nanofibers, mesoporous, to bamboo-like, while at the same time, metastable γ-phase domains increase in these PA6 nanostructures. Brunauer-Emmett-Teller (BET) surface areas of solid, bamboo-like, and mesoporous PA6 nanofibers rise from 16, 20.9, to 25 m(2)/g. This study shows that interfacial interaction in AAO template fabrication can be used in manipulating the morphology and crystallization of one-dimensional polymer nanostructures. It also provides us a simple and novel method to create porous PA6 nanofibers with a large surface area.

17.
Mar Pollut Bull ; 105(1): 422-9, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26872542

ABSTRACT

Based on geochemical and magnetic approaches, the distribution, sources, and health risk of trace metals in surface sediments from a seashore tourist city were investigated. A significant correlation was found between magnetic susceptibility (χ) and trace metals, which suggested that levels of trace metals in the sediments can be effectively depicted by the magnetic approach. The spatial distribution of χ and trace metals matched well with the city layout with relatively higher values being found in the port and busy tourist areas. This result, together with enrichment factors (EFs) and Tomlinson pollution load index (PLI) of metals, suggested that the influence of human activities on the coastal environment was noticeable. Principal component analysis (PCA) indicated that trace metals in the sediments were derived from both anthropogenic and natural sources. Noncarcinogenic risk assessment showed that there was no potential health risk of exposure to metals by means of ingestion or inhalation.


Subject(s)
Environmental Monitoring , Metals/analysis , Water Pollutants, Chemical/analysis , China , Geologic Sediments/analysis , Geologic Sediments/chemistry , Humans , Metals, Heavy/analysis , Risk Assessment , Trace Elements/analysis
18.
ACS Biomater Sci Eng ; 2(4): 489-493, 2016 Apr 11.
Article in English | MEDLINE | ID: mdl-33465852

ABSTRACT

Herein we for the first time demonstrated a scalable and simple fabrication of polydopamine nanotubes by using curcumin crystal as templates. BET surface area of obtained polydopamine nanotubes is 51.9 m2/g. Polydopamine nanotubes show great potential as biocompatible porous nanomaterials.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 864-70, 2015 Feb 25.
Article in English | MEDLINE | ID: mdl-25280333

ABSTRACT

The coordination structures formed by calcium complexes with nicotinamide (na), isonicotinamide (ina) and picolinamide (pa) and praseodymium bromide-na are reported. The structures of CaCl2·(C6H6N2O)2·2H2O (Ca-na), CaCl2·(C6H6N2O)2·4H2O (Ca-ina), CaCl2·(C6H6N2O)2·5H2O (Ca-pa) and PrBr3·(C6H6N2O)2·6H2O (PrBr-na) in the solid state have been characterized by X-ray single crystal diffraction, FTIR, FIR, THz and Raman spectroscopies. Carbonyl oxygen of nicotinamide is coordinated to Ca(2+), but it is O-monodentate (carbonyl oxygen) and N,O-bidentate ligand (pyridyl nitrogen and carbonyl oxygen) for Pr(3+) to form a chain structure in PrBr-na. For isonicotinamide, only carbonyl oxygen atom is coordinated to Ca(2+). Pyridyl nitrogen and carbonyl oxygen of picolinamide are coordinated to Ca(2+) to form a five-membered ring structure. The crystal structure and spectroscopic results indicate the differences of the coordination of Ca and Pr ions, the changes of hydrogen bonds and conformation of the ligands induced by complexation. Unlike transition metal ions, Sr(2+) or lanthanide ions, Ca(2+) is inclined to coordinate to carbonyl oxygen atoms of the ligands.


Subject(s)
Bromides/chemistry , Calcium Chloride/chemistry , Calcium/chemistry , Niacinamide/chemistry , Picolinic Acids/chemistry , Praseodymium/chemistry , Amides/chemistry , Carbon/chemistry , Hydrogen Bonding , Ions , Ligands , Metals/chemistry , Nitrogen/chemistry , Oxygen/chemistry , Spectrophotometry , Spectrophotometry, Infrared , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman , X-Ray Diffraction
20.
Article in English | MEDLINE | ID: mdl-24553916

ABSTRACT

Recent studies report that a conflict between information from the visual system and vestibular system is one of the main reasons for induction of motion sickness (MS). We may be able to clarify the integration mechanism of visual and vestibular information using an animal model with a visual defect, the retinal degeneration fast (rdf) mouse, and the role of vestibular information in the pathogenesis of MS. The rdf mice and wild-type Kunming mice were subjected to rotary stimulation to induce MS. Conditioned taste anorexia to saccharin solution and behavior score were used to observe the differences in MS sensitivity between two types of mice. The decrease in intake of saccharin solution and the behavior score in rdf mice were greater than those in normal mice. After rotatory stimulation, the reduction of intake mass and the behavior score were greater in rdf mice compared to those of normal mice. The rdf mice were more sensitive to rotation than normal mice. We conclude that visual information plays a role in the pathogenesis of MS. Visual information and vestibular information impact each other and integrate through certain channels in the central nervous system in mice.


Subject(s)
Motion Sickness/physiopathology , Retinal Degeneration/physiopathology , Animals , Anorexia , Conditioning, Psychological , Disease Models, Animal , Drinking , Male , Mice , Motion Sickness/etiology , Physical Stimulation/adverse effects , Rotation/adverse effects , Saccharin , Severity of Illness Index , Time Factors
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