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1.
Talanta ; 215: 120928, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32312465

RESUMO

Cobalt oxyhydroxide nanoflakes (CoOOH NFs), a typical two-dimensional (2D) nanomaterials, were found to induce chemiluminescence (CL) of luminol since the oxidase-like activity of CoOOH NFs enables the dissolved oxygen to generate various radicals (OH, O2-and 1O2) even if without the addition of oxidants such as hydrogen peroxide, and these radicals could be scavenged by glutathione (GSH), making GSH could be detected sensitively in the range of 10 nM to 1 µM with the detection limit of 6.4 nM.

2.
Cancer Biother Radiopharm ; 35(4): 277-283, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32159381

RESUMO

Objective: This study aimed at investigating the specific roles of laminarin from seaweed (Laminaria japonica) in hepatocellular carcinoma (HCC) and its potential mechanisms related to senescence marker protein-30 (SMP-30). Materials and Methods: Human HCC cell lines, including Bel-7404 and HepG2, were incubated with different concentrations of laminarin (0, 5, 15, 25, 35, and 45 mg/mL). The cell viability and apoptosis rates were detected by WST-8 cell proliferation assay and flow cytometry, respectively. Hepa 1-6 tumor-bearing mice were injected with different concentrations of laminarin (400, 800, and 1200 mg/kg·d), and tumor volume and weight were measured. The expression of SMP-30 was detected in laminarin-treated Bel-7404 and HepG2 HCC cells and LO2 normal liver cells by quantitative real-time PCR and Western blotting. Results: The treatment with laminarin (48 h) significantly decreased the viability and increased the apoptosis rates of Bel-7404 and HepG2 cells in a dose-dependent manner. The injection of laminarin also significantly decreased the tumor volumes (beginning on the 10th day) and tumor weights (30 d post-injection) of mice in a dose-dependent manner. In addition, the treatment with laminarin (35 mg/mL for 48 h) significantly upregulated SMP-30 in Bel-7404 and HepG2 cells but not in LO2 cells. Conclusion: Laminarin inhibited the proliferation of Bel-7404 and HepG2 cells and inhibited the growth of tumors in Hepa 1-6 tumor-bearing mice by upregulating SMP-30.

3.
Biochem Pharmacol ; 177: 113926, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32217098

RESUMO

BACKGROUND AND PURPOSE: Indoleamine 2, 3-dioxygenase 1 (IDO1) has been linked to neuropathic pain and IDO1 inhibitors have been shown to reduce pain in animals. Some studies have indicated that IDO1 expression increased after neuropathic pain in hippocampus and spinal cord, whether these changes existing in anterior cingulate cortex (ACC) and amygdala remains obscure and how IDO1 inhibition leads to analgesia is largely unknown. Here, we evaluated the antinociceptive effect of PCC0208009, an indirect IDO1 inhibitor, on neuropathic pain and examined the related neurobiological mechanisms. EXPERIMENTAL APPROACH: The effects of PCC0208009 on pain, cognition and anxiogenic behaviors were evaluated in a rat model of neuropathic pain. Motor disorder, sedation and somnolence were also assessed. Biochemical techniques were used to measure IDO1-mediated signaling changes in ACC and amygdala. KEY RESULTS: In rats receiving spinal nerve ligation (SNL), IDO1 expression level was increased in ACC and amygdala. PCC0208009 attenuated pain-related behaviors in the formalin test and SNL model and increased cognition and anxiogenic behaviors in SNL rats at doses that did not affect locomotor activity and sleeping. PCC0208009 inhibited IDO1 expression in ACC and amygdala by inhibiting the IL-6-JAK2/STAT3-IDO1-GCN2-IL-6 pathway. In addition, PCC0208009 reversed synaptic plasticity at the functional and structural levels by suppressing NMDA2B receptor and CDK5/MAP2 or CDK5/Tau pathway in ACC and amygdala. CONCLUSION AND IMPLICATIONS: These results support the role of IDO1-mediated molecular mechanisms in neuropathic pain and suggest that the IDO1 inhibitor PCC0208009 demonstrates selective pain suppression and could be a useful pharmacological therapy for neuropathic pain.

4.
Am J Chin Med ; 48(2): 463-485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32138532

RESUMO

Oxidative stress (OS) is the common mechanism for age-related diseases. The co-occurrence of osteoporosis (OP) and cardiovascular disease (CVD) in postmenopausal women makes it warranted to find a holistic approach for treatment of multiple diseases or conditions. The rhizome of Ligusticum chuanxiong Hort. (CX), which has high anti-oxidant properties and is widely used for CVD treatment in China, might be the potential candidate. In the present study, CX ethanol extract (CXE) was applied to H2O2 induced MG63 cells to study its effects and mechanisms on osteoblastogenesis against OS. CXE was then administered to six-month-old Sprague Dawley sham or ovariectomized (OVX) rats fed either a low saturated fat-sucrose (LFS) or a high fat-sucrose (HFS) diet for 12 weeks, to confirm its anti-osteoporotic effects. The results demonstrated that CXE directly improved proliferation and differentiation in vitro in an H2O2-induced osteoblast cell model by attenuating cellular reactive oxygen species levels and inhibiting osteoblast apoptosis via PI3K/Akt signaling pathway. CXE significantly improved bone properties as revealed by the increase in trabecular bone mineral density and decrease in trabecular separation at proximal metaphysis of the tibia (PT) in HFS-fed OVX rats but not in LFS-fed OVX rats. CXE ameliorated dyslipidemia, greatly reduced lipid deposition and malondialdehyde levels, improved activities of superoxide dismutase, catalase and glutathione peroxidase in the livers of HFS-fed OVX rats. In conclusion, CXE could favor osteoblastogenesis against OS. The ability of CXE to reduce bone loss in HFS-fed OVX rats was associated with its abilities to correct dyslipidemia, and reduce lipid deposition and OS levels.

5.
Anal Chem ; 92(5): 4046-4052, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32048509

RESUMO

Isothermal nucleic acid amplification technology has been widely adopted for analytical chemistry with the purpose of sensitivity improvement. Herein we present an ultrasensitive concatenated hybridization chain reaction (C-HCR) based surface-enhanced Raman scattering (SERS) immunoassay by forming antibody-antigen-aptamer heterosandwich structures with the model analyte of total prostate specific antigens (tPSA). In the C-HCR, two HCRs, one proceeds with two hairpins and the other with four biotin-modified hairpins, are coupled, making the formation of DNA nanofirecrackers with the lengths longer than 200 nm and more than four hundred million binding sites of streptavidin modified enzymes. These types of DNA nanofirecrackers through the aptamer encoded linker strand to form heterosandwich structures could provide a general signal application platform such as enzyme catalysis with high amplification efficiency. As a proof of concept, the Au@Ag core-shell nanostructure based SERS immunoassay with excellent signal amplification has been developed by employing the streptavidin modified alkaline phosphatase (SA-ALP) through its catalysis of 2-phospho-l-ascorbic acid trisodium salt (AAP) to form Au@Ag core-shell nanostructures via the formation of ascorbic acid (AA) to reduce AgNO3 and deposition of silver element on gold nanorods (AuNRs). The newly developed method has a detection limit as low as 0.94 fg/mL and has successfully achieved the detection of serum samples from clinical patients, which was consistent with the clinical test results, showing that this C-HCR strategy to form DNA nanofirecrackers has great potential in clinical applications.

6.
Int J Food Sci Nutr ; 71(2): 211-220, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31266395

RESUMO

A-type epigallocatechin-3-gallate (EGCG) and epicatechin-3-O-gallate (ECG) dimers have multiply biological activities. In this study, the pharmacokinetics of them were investigated in mice after a single dose intravenous administration, and the metabolites in mice plasma and urine were investigated by ultra-performance liquid chromatography-Quadrupole-time of flight mass spectrometer (UPLC-QTOF-MS). Our results showed that the half-life (t1/2) of A-type EGCG and ECG dimers were 116.37 min and 33.04 min, respectively, and the maximal concentration in plasma was 32.81 µg/mL and 55.59 µg/mL, respectively. It was found that two dimers were firstly experienced by quinone methide (QM) fission to form the EGCG and ECG analogue, and the phase II metabolites were generated subsequently. The main metabolites in plasma and urine were glucuronidation and sulphation derivatives. In addition, small molecule weight of phenolic acids were detected in urine.

7.
PLoS Pathog ; 15(10): e1008079, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31603949

RESUMO

Interferon-inducible p200 family protein IFI204 was reported to be involved in DNA sensing, and subsequently induces the production of type I interferons and proinflammatory mediators. However, its function in the regulation of antiviral innate immune signaling pathway remains unclear. Here we reported a novel role of IFI204 that specifically inhibits the IRF7-mediated type I interferons response during viral infection. IFI204 and other p200 family proteins are highly expressed in mouse hepatitis coronavirus-infected bone marrow-derived dendritic cells. The abundant IFI204 could significantly interact with IRF7 in nucleus by its HIN domain and prevent the binding of IRF7 with its corresponding promoter. Moreover, other p200 family proteins that possess HIN domain could also inhibit the IRF7-mediated type I interferons. These results reveal that, besides the positive regulation function in type I interferon response at the early stage of DNA virus infection, the interferon-inducible p200 family proteins such as IFI204 could also negatively regulate the IRF7-mediated type I interferon response after RNA virus infection to avoid unnecessary host damage from hyper-inflammatory responses.


Assuntos
Infecções por Coronavirus/imunologia , Coronavirus/imunologia , Fator Regulador 7 de Interferon/metabolismo , Interferon Tipo I/imunologia , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Células 3T3 , Células A549 , Animais , Linhagem Celular , Infecções por Coronavirus/patologia , Células HEK293 , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Inflamação/patologia , Fator Regulador 7 de Interferon/genética , Camundongos , Células RAW 264.7
8.
Pharmacol Rep ; 71(6): 1006-1013, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563017

RESUMO

BACKGROUND: Approaches promoting fibroblast-like synoviocytes (FLS) apoptosis are considered as a meaningful strategy for rheumatoid arthritis (RA) treatment. We have previously reported the anti-arthritic effect of penta-acetyl geniposide ((Ac)5GP, an active derivative of geniposide) on adjuvant-induced arthritis (AIA) rats in vivo. The present study aimed to investigate the pro-apoptotic effect of (Ac)5GP on AIA FLS in vitro and the underlying molecular mechanisms. METHODS: Rat AIA was induced by complete Freund's adjuvant, and FLS were primary-cultured from synovial tissues. AIA FLS were treated with (Ac)5GP (50, 100 and 200 µM) for 48 h and cell proliferation and apoptosis were respectively examined. The involvement of apoptosis-related proteins (Bax, Bcl-2 and caspase 3) and nuclear factor kappa B (NF-κB) signaling pathway was checked. RESULTS: (Ac)5GP inhibited the viability of AIA FLS and reduced the percentage of Ki67-positive cells in AIA FLS. Particularly, (Ac)5GP promoted AIA FLS apoptosis in vitro by inducing apoptotic nuclear morphology, facilitating DNA ladder formation and increasing percentages of both early and late apoptotic cells. (Ac)5GP treatment on AIA FLS decreased Bcl-2 protein level whereas increased the levels of Bax and caspase 3 proteins. Moreover, (Ac)5GP reduced the degradation and phosphorylation of IκBα, down-regulated NF-κB p65 protein level in nucleus and inhibited NF-κB p65 nuclear translocation. CONCLUSIONS: (Ac)5GP had a potent pro-apoptotic effect on AIA FLS in vitro, which is associated with regulating apoptosis-related proteins and inhibiting NF-κB activation.

9.
J Agric Food Chem ; 67(40): 11044-11052, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31545599

RESUMO

Persimmon condensed tannins (PT) are highly polymerized (mDP = 26) and highly galloylated (72%) proanthocyanidins. Its pleiotropic effects in oxidation resistance, neuroprotection, hypolipidemia, and cardio-protection both in vitro and in vivo were widely reported. Because large proanthocyanidins are unlikely to be absorbed in the gastrointestinal tract, it is believed that the interaction of PT with biological membranes may play a crucial role in its biological activities. In the present study, the capacities of PT adsorbing to membrane, partitioning into membrane, and its influence on the membrane fluidity were investigated by fluorescence quenching, isothermal titration calorimetry (ITC) and fluorescence anisotropy measurements in a biomembrane-mimetic system composed of 1-palmitoyl-2-oleoylphosphatidylcholine (POPC), 1-palmitoyl-2-oleoylphosphatidylethanolamine (POPE), sphingomyelin (SPM), and cholesterol (CHOL). Besides, the effects of PT on the morphology and integrity of the cell membrane were studied by scanning electron microscopy (SEM) and fluorescence staining in the 3T3-L1 cell model. The results suggested that PT could affect cell membrane rafts domains, destroy the cell membrane morphology, and regulate cell membrane fluidity, which might contribute to its biological effects.


Assuntos
Membrana Celular/química , Diospyros/química , Extratos Vegetais/química , Proantocianidinas/química , Animais , Fenômenos Biofísicos , Membrana Celular/metabolismo , Colesterol/química , Colesterol/metabolismo , Frutas/química , Fluidez de Membrana , Camundongos , Células NIH 3T3 , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Extratos Vegetais/metabolismo , Polimerização , Proantocianidinas/metabolismo , Esfingomielinas/química , Esfingomielinas/metabolismo
10.
ACS Appl Mater Interfaces ; 11(32): 29158-29166, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31313570

RESUMO

Highly active, stable, and cost-effective enzyme-mimicking nanomaterials (nanozymes) hold the potential to be an alternative to replace natural enzymes for the catalysis of enzyme-like reactions in various applications. Here, novel 3D ruthenium-based metal-organic gels (Ru-MOGs) with fibrillar network structures have been successfully synthesized using a facile one-step strategy at room temperature. Surprisingly, the developed 3D fibrillar networked Ru-MOGs simultaneously possess intrinsic horseradish peroxidase and NADH peroxidase mimetic activities. Meanwhile, the horseradish peroxidase mimetic catalytic activity displays well in both acidic environment and alkaline condition. Kinetic analysis reveals that Ru-MOGs make an effective peroxidase mimic with exceptionally high catalytic velocity (Vm), substrate binding affinity (Km), and catalytic efficiency (Kcat/Km). Furthermore, as a proof-of-concept, the mimetic enzyme property of this material was further used to establish a chemiluminescent biosensing platform for glucose detection. These easily synthesized Ru-MOGs as highly active and novel nanozymes not only suggests a bright future for the nanomaterials as enzyme mimics but also provides new insights into the properties of MOGs, greatly broadening and advancing their applications in biocatalysis and bioassays.


Assuntos
Materiais Biomiméticos/química , Nanoestruturas/química , Peroxidases/química , Rutênio/química , Géis , Peroxidase do Rábano Silvestre/química
11.
Adv Colloid Interface Sci ; 270: 165-190, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31265929

RESUMO

Carbon dots (CDs), as a new type of luminescent zero-dimensional carbon nanomaterial, have been applied in a variety of fields. Currently, functionalization of CDs is an extremely useful method for effectively tuning their intrinsic structure and surface state. Heteroatom doping and surface modification are two functionalization strategies for improving the photophysical performance and broadening the range of applications for fluorescent CDs. Heteroatom doping in CDs can be used to tune their intrinsic properties, which has received significant research interests because of its simplicity. Surface modification can be applied for varying active sites and the functional groups on the CDs surface, which can endow fluorescent CDs with the unique properties resulting from functional ligand. In this review, we summarize the structural and physicochemical properties of functional CDs. We focused our review on the latest developments in functionalization strategies for CDs and discuss the detailed characteristics of different functionalization methods. Ultimately, we hope to inform researchers on the latest progress in functionalization of CDs and provide perspectives on future developments for functionalization of CDs and their potential applications.

12.
Anal Chem ; 91(17): 11023-11029, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31266308

RESUMO

Förster resonance energy transfer (FRET) by using fluorescent carbon dots (CDs) as energy donors shows potential for biosensing and bioimaging. However, it remains underused and underestimated for CDs as a building block for FRET owing to the low efficiency and complex operation originating from the surface modification of CDs. To overcome these limitations, herein we develop a novel FRET soft nanoball (fretSNB) in which thousands of green CDs and black hole quencher 2 (BHQ-2) dyes are loaded, and FRET occurs from CDs to BHQ-2 dyes with the consequence of effective fluorescence quenching. These fretSNBs can be ruptured in the presence of phospholipase A2 (PLA2) released in a process of duplex-specific nuclease (DSN)-assisted target recycling amplification (TRA), making the fluorescence of CDs recovered. Thus, a dual amplification strategy is successfully developed for amplified detection of microribonucleic acids (miRNAs) in the concentration range 0.025-10 nM with a limit of detection (3σ) reaching 16.5 pM which is about 515 times lower than without fretSNBs. In addition, the developed strategy exhibits high selectivity for discrimination of a single nucleotide difference and capability to detect miRNAs extracted from cells, suggesting excellent potential in biomedical analysis and clinical diagnosis.

13.
Talanta ; 203: 220-226, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202329

RESUMO

Biothiols play important roles in regulating redox balance in biological systems, but their discrimination is challengeable. In this work, a colorimetric nanosensing array for biothiols was established, which was composed of gold nanorods (AuNRs) and metal ions (Hg2+, Pb2+, Cu2+, Ag+). By employing label-free AuNRs as the colorimetric probe, and the color and spectral changes of AuNRs as the output signal, principal component analysis (PCA) was applied to processing the signal and generating a clustering map. Due to the different binding affinity between biothiols and metal ions, AuNRs exhibited a unique pattern to form a fingerprint-like colorimetric array, which was able to discriminate five biothiols by the naked eyes. This strategy combines PCA and sensor array to achieve rapid and accurate discrimination and detection of biothiols. In addition, the method shows the great potential in analysis of biothiols in human urine samples.


Assuntos
Colorimetria/métodos , Ouro/química , Nanotubos/química , Compostos de Sulfidrila/urina , Acetilcisteína/urina , Cisteamina/urina , Cisteína/urina , Glutationa/urina , Homocisteína/urina , Humanos , Análise de Componente Principal
14.
Chem Commun (Camb) ; 55(45): 6437-6440, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31095140

RESUMO

A precise ricin A-chain (RTA) delivery system was constructed by coupling RTA to carbon dots (CDs) with a distinctive capacity for Golgi targeting. The rational design shows efficient internalization and an exact pathway to the cytoplasm for RTA to exert its real toxic action since it could avoid lysosome degradation.


Assuntos
Carbono/química , Sistemas de Liberação de Medicamentos , Complexo de Golgi/química , Pontos Quânticos/química , Ricina/química , Citoplasma/química , Citoplasma/metabolismo , Complexo de Golgi/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Ricina/toxicidade
15.
Anal Chem ; 91(10): 6761-6768, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31020834

RESUMO

Nonalcoholic fatty liver disease (NAFLD) can progress gradually to liver failure, early warning of which is critical for improving the cure rate of NAFLD. In situ imaging and monitoring of overexpressed miR-21 is an advanced strategy for NAFLD diagnosis. However, this strategy usually suffers from the high background imaging in living cells owing to the complexity of the biological system. To overcome this problem, herein, we have developed a one-donor-two-acceptor nanoprobe by assembling gold nanoparticles (AuNPs) coupled with BHQ2 (AuBHQ) and quantum dots (QDs) through DNA hybridization for imaging of miR-21 in living cells. The fluorescence of QDs was quenched up to 82.8% simultaneously by the AuNPs and the BHQ2 via nanometal surface energy transfer and fluorescence resonance energy transfer, reducing the background signals for target imaging. This low background fluorescent nanoprobe was successfully applied for imaging the target miR-21 in nonalcoholic fatty liver cells by catalyzing the disassembly of QDs with the AuBHQ and the fluorescence recovery of QDs. In addition, the sensitivity of this nanoprobe has also been enhanced toward detecting miR-21 in the range of 2.0-15.0 nM with the detection limit (LOD, 3σ) of 0.22 nM, which was 13.5 times lower than that without BHQ2. The proposed approach provides a new way for early warning, treatments, and prognosis of NAFLD.

16.
Materials (Basel) ; 12(8)2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31010012

RESUMO

Composites of 7055 aluminum (Al) matrix reinforced with SiC particles were prepared using the spray deposition method. The volume fraction of the phase reinforced with SiC particles was 17%. The effect of the introduction of SiC particles on the deposited microstructure and properties of the composites was studied in order to facilitate the follow-up study. The structure and element enrichment zone of spray-deposited SiCp/7055 Al matrix composites were studied by Optical Microscope (OM), X-ray diffraction (XRD), Scanning Electronic Microscopy (SEM) and Transmission electron microscopy (TEM). The results show that the reinforcement phases of the SiC particles were uniformly distributed on the macro and micro levels, and a few SiC particles were segregated into annular closed regions. C and Si on the surface of SiC particles diffused to the Al matrix. The distribution of the two elements was gradient weakening with SiC particles as the center, and the enrichment zones of Si, Mg and Cu formed in the middle of the closed annular area of a few SiC particles. The enrichment zones were mainly composed of alpha-Al, SiC, Al2CuMg, Al2Cu and MgZn2. AlCu and AlMgCu phase precipitate on the surface of the SiC particles, beside the particle boundary, and had the characteristics of preferred nucleation. They tended to grow at the edges and corners of SiC particles. It was observed that the formation of nanoparticles in the alloy had a pinning effect on dislocations. The different cooling rates of the SiC particles and the Al matrix led to different aluminum liquid particle sizes, ranging from 20 to 150 µm. In the region surrounded by SiC particles, the phenomenon of large particles extruding small particles was widespread. Tearing edges and cracks continued to propagate around the SiC particles, increasing their propagation journey and delaying the fracture of the materials.

17.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(1): 62-65, 2019 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-30854821

RESUMO

OBJECTIVE: This study aims to observe the efficacy of vacuum sealing drainage (VSD) by continuous negative pressure drainage and saline irrigation in the treatment of oral and maxillofacial space infection. METHODS: Retrospective analysis was conducted on 116 cases of maxillofacial space infection, and clinical data were collected to compare the therapeutic effects of routine incision with drainage treatment (traditional treatment group, 58 cases) and VSD treatment (VSD group, 58 cases). RESULTS: The length of hospital stay, white blood cell count, scar length, frequency of dressing change, and pain degree of patients in the VSD group were all lower than those in the traditional treatment group. Moreover, the improvement degree of mouth opening in the VSD groups was better than that in the traditional treatment group (P<0.05). CONCLUSIONS: VSD is a more effective method for the treatment of oral and maxillofacial space infection.


Assuntos
Drenagem , Doenças da Boca , Infecção da Ferida Cirúrgica , Líquidos Corporais , Humanos , Doenças da Boca/terapia , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/terapia , Vácuo
18.
Bot Stud ; 60(1): 5, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30923953

RESUMO

BACKGROUND: Melastoma has undergone rapid species radiation during the last one million years, and circumscription of some species in the genus has remained controversial. Melastoma kudoi, an erect species narrowly endemic to central Taiwan was previously treated as a synonym of M. intermedium, a semicreeping hybrid between the erect species M. candidum and the creeping M. dodecandrum, making its identity questionable. We addressed this question based on molecular and morphological data. RESULTS: Phylogenetic analyses based on nrITS sequence data revealed that M. kudoi is most closely related to M. dodecandrum. Further analyses of six nuclear genes (cam, chi, gapC, gbss, tpi and vr) and two chloroplast markers (trnL-trnF and psbA) showed that M. kudoi is well diverged from its close relatives. Morphologically, it is also easily distinguished from related species by its erect habit, center-positioned stigma, and spreading, basally enlarged hairs on the hypanthium. CONCLUSIONS: Both molecular phylogenetic and morphological data suggest that M. kudoi is well separated from M. intermedium, M. dodecandrum, and O. scaberrima, and should be treated as a distinct species. Taxonomic treatment and detailed description of M. kudoi are provided.

19.
Liver Int ; 39(8): 1504-1513, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30721562

RESUMO

BACKGROUND & AIMS: Insulin resistance is strongly associated with non-alcoholic fatty liver disease, a chronic, obesity-related liver disease. Increased endoplasmic reticulum (ER) stress plays an important role in the development of insulin resistance. In this study, we investigated the roles of miRNAs in regulating ER stress in the liver of rats with obesity. METHODS: We used miRNA microarray to determine the miRNA expression profiles in the liver of rats fed with a high fat diet (HFD). We used prediction algorithms and luciferase reporter assay to identify the target gene of miRNAs. To overexpress the miRNA miR-30b or inhibit miR-30b rats were injected with lentivirus particles containing PGLV3-miR-30b or PGLV3-miR-30b antimiR through tail vein. Hepatic steatosis was measured using transient elastography in human subjects. RESULTS: Our data showed that miR-30b was markedly up-regulated in the liver of HFD-treated rats. Bioinformatic and in vitro and in vivo studies led us to identify sarco(endo)plasmic reticulum Ca2+ -ATPase 2b (SERCA2b), as a novel target of miR-30b. Overexpression of miR-30b induced ER stress and insulin resistance in rats fed with normal diet, whereas inhibition of miR-30b by miR-30b antimiR suppressed ER stress and insulin resistance in HFD-treated rats. Finally, our data demonstrated that there was a positive correlation between serum miR-30b levels and hepatic steatosis or homoeostasis model assessment of insulin resistance (HOMA-IR) in human subjects. CONCLUSIONS: Our findings suggest that miR-30b represents not only a potential target for the treatment of insulin resistance, but also a non-invasive disease biomarker of NAFLD.

20.
Brain Res Bull ; 146: 302-309, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30711623

RESUMO

Accumulating reports have highlighted an association between excess retinoids and depression development. Retinoic acid receptor α (RARα) is implicated in the activation of hypothalamus-pituitary-adrenal (HPA) axis and closely involved in the etiology of depression, suggesting it might be a novel target of antidepressant. This study investigated the antidepressant potential of Ro41-5253 (a selective RARα antagonist) and related mechanisms using a depression rat model imitated by social isolation and chronic unpredicted mild stress (CUMS). Sucrose preference test (SPT), open field test (OFT) and forced swimming test (FST) were applied to assess the antidepressant-like effect. HPA axis activity, RARα expression in hypothalamic paraventricular nucleus (PVN) and hypothalamus, and protein levels of brain-derived neurotrophic factor (BDNF) and synapse-related proteins (PSD95, SYP, MAP2) in hippocampus were measured, respectively. We found that Ro41-5253 treatment ameliorated the depressive-like behaviors in CUMS rats, as evidenced by increased sucrose preference in SPT, raised numbers of crossing and rearing in OFT, reduced immobility time and prolonged swimming time in FST. The HPA axis hyperactivity was attenuated by Ro41-5253 (1 mg/kg) treatment, indicated by reduced serum corticosterone level, decreased adrenal gland index, reduced corticotrophin-releasing hormone protein level in hypothalamus, and recovered hypothalamic glucocorticoid receptor protein level. In addition, Ro41-5253 (1 mg/kg) treatment downregulated RARα protein expression in hypothalamic PVN and hypothalamus, and increased the protein levels of BDNF, PSD95, SYP and MAP2 in the hippocampus. We concluded that Ro41-5253 had antidepressant-like effects on CUMS rats by downregulating HPA axis hyperactivity and improving the hippocampal neuronal deficits.

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