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1.
Int J Mol Sci ; 25(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38673941

RESUMO

Abdominal aortic aneurysm (AAA) is a serious vascular disease which is associated with vascular remodeling. CD38 is a main NAD+-consuming enzyme in mammals, and our previous results showed that CD38 plays the important roles in many cardiovascular diseases. However, the role of CD38 in AAA has not been explored. Here, we report that smooth-muscle-cell-specific deletion of CD38 (CD38SKO) significantly reduced the morbidity of AngII-induced AAA in CD38SKOApoe-/- mice, which was accompanied with a increases in the aortic diameter, medial thickness, collagen deposition, and elastin degradation of aortas. In addition, CD38SKO significantly suppressed the AngII-induced decreases in α-SMA, SM22α, and MYH11 expression; the increase in Vimentin expression in VSMCs; and the increase in VCAM-1 expression in smooth muscle cells and macrophage infiltration. Furthermore, we demonstrated that the role of CD38SKO in attenuating AAA was associated with the activation of sirtuin signaling pathways. Therefore, we concluded that CD38 plays a pivotal role in AngII-induced AAA through promoting vascular remodeling, suggesting that CD38 may serve as a potential therapeutic target for the prevention of AAA.


Assuntos
ADP-Ribosil Ciclase 1 , Angiotensina II , Aneurisma da Aorta Abdominal , Camundongos Knockout , Miócitos de Músculo Liso , Remodelação Vascular , Animais , Masculino , Camundongos , ADP-Ribosil Ciclase 1/metabolismo , ADP-Ribosil Ciclase 1/genética , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/patologia , Modelos Animais de Doenças , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Cadeias Pesadas de Miosina/metabolismo , Cadeias Pesadas de Miosina/genética , Transdução de Sinais , Remodelação Vascular/genética
2.
Can J Physiol Pharmacol ; 101(7): 369-381, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37192549

RESUMO

Obesity is a metabolic syndrome characterized by abnormal lipid deposition and energy imbalance. CD38 is a single-chain transmembrane glycoprotein widely expressed in a variety of cell types. The roles of skeletal muscle and brown fat in CD38 deficiency under HFD-induced obesity remain unknown. In this study, we established obesity model with HFD and examined the changes in metabolites with metabonomics. Our results showed that CD38 expression was increased in muscle and brown fat after HFD treatment. Moreover, the results of metabonomics showed that CD38 deficiency significantly altered the metabolites in energy metabolism, cofactor generation, and redox homeostasis. Furthermore, CD38 deficiency reduced the expressions of NADPH oxidase 2 and FASN in mRNA level. We found that the expressions of Sirt1, Sirt3, and PGC1α were upregulated in CD38-deficient muscle tissue. In brown fat, the Sirt1-3, cell death inducing DFFA-like effector A, ELOVL3, and Dio2 expressions were increased in CD38-deficient mice. Our results showed the uncoupling protein 1 expression was upregulated. And NAD+ supplementation increased the expression of Sirt1 and PGC1α after palmitic acid treatment. Taken together, our results demonstrated that the protection of CD38 deficiency on HFD-induced obesity was related to the inhibition of oxidative stress and increasing energy expenditure via activating NAD+/Sirtuins signaling pathways in muscle and brown fat.


Assuntos
Tecido Adiposo Marrom , NAD , Animais , Camundongos , Tecido Adiposo Marrom/metabolismo , Dieta Hiperlipídica , Metabolismo Energético , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , NAD/metabolismo , Obesidade/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo
3.
Nano Lett ; 22(4): 1483-1490, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35148112

RESUMO

Single-photon sources play a key role in photonic quantum technologies. Semiconductor quantum dots can emit indistinguishable single photons under resonant excitation. However, the resonance fluorescence technique typically requires cross-polarization filtering, which causes a loss of the unpolarized quantum dot emission by 50%. To solve this problem, we demonstrate a method for generating indistinguishable single photons with optically controlled polarization by two laser pulses off-resonant with neutral exciton states. This scheme is realized by exciting the quantum dot to the biexciton state and subsequently driving the quantum dot to an exciton eigenstate. By combining with a magnetic field, we demonstrated the generation of photons with optically controlled polarization (the degree of polarization is 101(2)%), laser-neutral exciton detuning up to 0.81 meV, high single-photon purity (99.6(1)%), and indistinguishability (85(4)%). Laser pulses can be blocked using polarization and spectral filtering. Our work makes an important step toward indistinguishable single-photon sources with near-unity collection efficiency.

4.
Int J Mol Sci ; 24(21)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37958991

RESUMO

Diabetic cardiomyopathy is one of the diabetes mellitus-induced cardiovascular complications that can result in heart failure in severe cases, which is characterized by cardiomyocyte apoptosis, local inflammation, oxidative stress, and myocardial fibrosis. CD38, a main hydrolase of NAD+ in mammals, plays an important role in various cardiovascular diseases, according to our previous studies. However, the role of CD38 in diabetes-induced cardiomyopathy is still unknown. Here, we report that global deletion of the CD38 gene significantly prevented diabetic cardiomyopathy induced by high-fat diet plus streptozotocin (STZ) injection in CD38 knockout (CD38-KO) mice. We observed that CD38 expression was up-regulated, whereas the expression of Sirt3 was down-regulated in the hearts of diabetic mice. CD38 deficiency significantly promoted glucose metabolism and improved cardiac functions, exemplified by increased left ventricular ejection fraction and fractional shortening. In addition, we observed that CD38 deficiency markedly decreased diabetes or high glucose and palmitic acid (HG + PA)-induced pyroptosis and apoptosis in CD38 knockout hearts or cardiomyocytes, respectively. Furthermore, we found that the expression levels of Sirt3, mainly located in mitochondria, and its target gene FOXO3a were increased in CD38-deficient hearts and cardiomyocytes with CD38 knockdown under diabetic induction conditions. In conclusion, we demonstrated that CD38 deficiency protected mice from diabetes-induced diabetic cardiomyopathy by reducing pyroptosis and apoptosis via activating NAD+/Sirt3/FOXO3a signaling pathways.


Assuntos
Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Sirtuína 3 , Animais , Camundongos , Apoptose , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatias Diabéticas/genética , Cardiomiopatias Diabéticas/metabolismo , Mamíferos/metabolismo , Miócitos Cardíacos/metabolismo , NAD/metabolismo , Estresse Oxidativo , Piroptose , Sirtuína 3/metabolismo , Volume Sistólico , Função Ventricular Esquerda
5.
Opt Express ; 30(7): 10229-10238, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35472995

RESUMO

Photonic crystal lasers with a high-Q factor and small mode volume are ideal light sources for on-chip nano-photonic integration. Due to the submicron size of their active region, it is usually difficult to achieve high output power and single-mode lasing at the same time. In this work, we demonstrate well-selected single-mode lasing in a line-defect photonic crystal cavity by coupling it to the high-Q modes of a short double-heterostructure photonic crystal cavity. One of the FP-like modes of the line-defect cavity can be selected to lase by thermo-optically tuning the high-Q mode of the short cavity into resonance. Six FP-like modes are successively tuned into lasing with side mode suppression ratios all exceeding 15 dB. Furthermore, we show a continuous wavelength tunability of about 10 nm from all the selected modes. The coupled cavity system provides a remarkable platform to explore the rich laser physics through the spatial modulation of vacuum electromagnetic field at submicron scale.

6.
Opt Lett ; 47(22): 6033-6036, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37219165

RESUMO

The exploration of parity-time (PT) symmetry in micro-/nano-cavity lasers has recently gained immense research interest. The PT symmetric phase transition to single-mode lasing has been achieved by arranging the spatial distribution of optical gain and loss in single or coupled cavity systems. In terms of photonic crystal (PhC) lasers, a non-uniform pumping scheme is usually employed to enter the PT symmetry-breaking phase in a longitudinal PT symmetric system. Instead, we use a uniform pumping scheme to enable the PT symmetric transition to the desired single lasing mode in line-defect PhC cavities based on a simple design with asymmetric optical loss. The flexible control of gain-loss contrast is realized by removing a few rows of air holes in PhCs. We obtain single-mode lasing with a side mode suppression ratio (SMSR) of around 30 dB without affecting the threshold pump power and linewidth. The output power of the desired mode is six times higher than that in multimode lasing. This simple approach enables single-mode PhC lasers without sacrificing the output power, threshold pump power, and linewidth of a multimode cavity design.

7.
Exp Eye Res ; 219: 109058, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35364100

RESUMO

PURPOSE: This study aimed to explore cellular localisation of CD38 in the retina and evaluate the role and potential mechanism of CD38 deficiency in retinal ischaemia/reperfusion (I/R) injury. METHODS: Six-to eight-week-old male CD38 knockout (KO) and wild-type mice in C57BL/6 background were used. Immunostaining was performed to determine the cellular localisation of CD38 in the retina. Haematoxylin and eosin staining and immunostaining of Brn3a were used to evaluate the retinal I/R injury. Western blotting was performed to detect toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), p-p65, ionised calcium-binding adapter molecule 1, Sirtuin1 (Sirt1), Ac-p65, and pro-inflammatory cytokines protein expression. RESULTS: CD38 was highly expressed in mouse retinal microglia and astrocytes/Müller cells. CD38 deficiency reduced I/R-induced retinal damage and retinal ganglion cell death. Following retinal I/R injury, TLR4, MyD88, nuclear factor-κB p-p65 (NF-κB p-p65), pro-inflammatory cytokines and CD38 protein levels were also upregulated. After I/R injury, retinal inflammation factors IL-1ß, IL-6, and TNF-α mRNA and protein levels were increased. IL-1ß, IL-6, and TNF-α were reduced in CD38 KO mice after I/R injury. Retinal I/R injury induced the activation of microglia, but this effect was also suppressed by KO of CD38. Additionally, retinal I/R induced a significant increase in Ac-p65 protein levels and decrease in Sirt1 protein levels, while this effect was greatly attenuated by KO of CD38. CONCLUSION: CD38 deficiency protects the retina from I/R injury by suppressing microglial activation partly via activating Sirt1-mediated suppression of TLR4/MyD88/NF-κB signalling.


Assuntos
Traumatismo por Reperfusão , Receptor 4 Toll-Like , Animais , Citocinas/metabolismo , Interleucina-6/metabolismo , Isquemia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Retina/metabolismo , Sirtuína 1/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
8.
Int J Gynecol Pathol ; 40(4): 333-341, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33021557

RESUMO

Most complete hydatidiform moles (CHMs) showcase an androgenetic nature of the nuclear genome. In the normal female embryo, one of the 2 X chromosomes is inactive. However, the status of X chromosome inactivation (XCI) in androgenetic CHMs remains unknown. Seventy-one androgenetic CHM tissues with the 46, XX karyotype were collected. Seventy-four normal female villi and 74 normal male villi were collected as controls. The expression of XCI markers (XIST, TSIX, and XACT) and an X-linked gene (CDX4) was detected by real-time polymerase chain reaction. Other XCI-associated genes were also examined, including the methylation status of the human androgen receptor gene (HUMARA) by methylation-specific polymerase chain reaction), and the expression of H3K27me3, USP21, and Nanog by Western blot and immunofluorescence, respectively. In addition, 126 CHMs and 63 normal female villous samples were collected for CDX4 immunohistochemical staining. The expression of XIST RNA was significantly lower, and TSIX RNA expression was significantly higher in androgenetic CHMs than that in normal female villi (both P<0.01). The expression of CDX4 mRNA in androgenetic CHMs was elevated compared with that in normal male and normal female villous samples (both P<0.01), and CDX4 protein expression was also higher than that in normal female villous samples (P<0.01). The expression of H3K27me3 was lower in androgenetic CHMs compared with that in normal female villi(P<0.01). The methylation pattern of HUMARA was found lacking in androgenetic CHMs. The expression of Nanog and UPS21 protein in androgenetic CHMs was higher than that in normal villi (both P<0.01). Both X chromosomes are active in androgenetic CHMs with the 46, XX karyotype, and the USP21-Nanog pathway may be involved in the disruption of XCI during this process.


Assuntos
Mola Hidatiforme/genética , RNA Longo não Codificante/genética , Neoplasias Uterinas/genética , Inativação do Cromossomo X/genética , Androgênios/metabolismo , Cromossomos Humanos X/genética , Metilação de DNA , Feminino , Proteínas de Homeodomínio/genética , Humanos , Mola Hidatiforme/patologia , Cariótipo , Proteína Homeobox Nanog/metabolismo , Gravidez , Receptores Androgênicos/genética , Trofoblastos/metabolismo , Ubiquitina Tiolesterase/metabolismo , Neoplasias Uterinas/patologia
9.
Can J Physiol Pharmacol ; 99(8): 803-811, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33356884

RESUMO

Inflammation-induced activation and dysfunction of endothelial cells play an important role in the pathology of multiple vascular diseases. Nicaraven, a potent hydroxyl radical scavenger, has recently been found to have anti-inflammatory roles; however, the mechanism of its action is not fully understood. Here we investigated the effects of Nicaraven on tumor necrosis factor α (TNFα) - induced inflammatory response in human umbilical vein endothelial cells and we explore the underlying mechanisms related to the nuclear factor-κB (NF-κB) signaling pathway. Our results showed that Nicaraven significantly reduced the reactive oxygen species production after TNFα stimulation. Nicaraven suppressed TNFα-induced mRNA expression of multiple adhesion molecules and pro-inflammatory cytokines, including vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), E-selectin, MCP-1, TNFα, interleukin-1ß (IL-1ß), IL-6, and IL-8. In addition, Nicaraven inhibited monocyte adhesion and reduced the protein levels of VCAM-1 and ICAM-1. Mechanistically, Nicaraven prevented TNFα-induced activation of NF-κB signaling pathway by suppressing the phosphorylation of NF-κB p65, IκBα, and IκB kinase (IKK)α/ß, stabilizing IκBα, and inhibiting the translocation of p65 from cytosol to nucleus. Finally, we showed that Nicaraven improved the functions of endothelial cells, seen as the upregulation of endothelial nitric oxide synthase and increased nitric oxide levels. Our findings indicated that Nicaraven effectively inhibits TNFα-induced endothelial activation and inflammatory response at least partly through inhibiting NF-κB signaling pathway.


Assuntos
NF-kappa B , Células Endoteliais da Veia Umbilical Humana , Humanos , Transdução de Sinais
10.
Opt Express ; 28(11): 16486-16496, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32549470

RESUMO

The effective manipulation of mode oscillation and competition is of fundamental importance for controlling light emission in semiconductor lasers. Here we develop a rate equation model which considers the spatially modulated gain and spontaneous emission, which are inherently governed by the ripple of the vacuum electromagnetic field in a Fabry-Pérot (FP) microcavity. By manipulating the interplay between the spatial oscillation of the vacuum field and external optical injection via dual-beam laser interference, single longitudinal mode operation is observed in a FP-type microcavity with a side mode suppression ratio exceeding 40 dB. An exploration of this extended rate equation model bridges the gap between the classical model of multimode competition in semiconductor lasers and a quantum-optics understanding of radiative processes in microcavities.

11.
Chemistry ; 25(8): 2043-2050, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30457684

RESUMO

Stereoselective polymerization of polar vinyl monomers has been a long-standing challenge because the employed transition-metal catalysts are easily poisoned by polar groups of monomers. In this contribution, a series of ß-diketiminato rare-earth metal complexes 1-5 (L1-5 Ln(CH2 SiMe3 )2 (THF)n , Ln=Gd-Lu, Y, and Sc) were successfully synthesized. In combination with AliBu3 and [Ph3 C][B(C6 F5 )4 ], complexes 1 c(Tb)-1 g(Tm) exhibited high activities and excellent isoselectivities for the polymerization of ortho-methoxystyrene (oMOS), in which, the polar methoxy group of oMOS did not poison but activated the polymerization through σ-π chelation to the active species together with the vinyl group. Moreover, the large Gd-attached precursor 1 b showed a higher activity, albeit with a slightly decreased isoselectivity. The small Sc-attached precursor 1 i was completely inert. Meanwhile, the spatial steric arrangement and the coordination mode of the ß-diketiminato ligand could clearly affect and even block oMOS polymerization. This work sheds new light on the coordination polymerization of polar monomers.

12.
Angew Chem Int Ed Engl ; 58(33): 11434-11438, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31166066

RESUMO

The utilization of 5-hydroxymethyl furfural (HMF) as a renewable feedstock for polymer synthesis has not yet been achieved as it is structurally asymmetric and contains three active functional groups. Reported here is the unprecedented step-growth copolymerization of HMF and dihydrosilanes, through a coordination mechanism, to afford linear poly(silyl ether)s in the presence of B(C6 F5 )3 and the heteroscorpionate zinc hydride complex LZnH [L=(Me Pz)2 CP(Ph)2 NPh, Me Pz=3,5-dimethylpyrazolyl]. The adduct B(C6 F5 )3 ⋅⋅⋅H⋅⋅⋅Zn, confirmed by NMR spectroscopy and DFT calculations, plays a key role in the synergistic catalysis, where B(C6 F5 )3 activates ZnH and stabilizes the Zn+ active species, and the sterically bulky ZnH effectively inhibits (C6 F5 )3 B from reacting with dihydrosilane to form (C6 F5 )3 B-H-Si, which facilely initiates ring opening of furan. The mechanism was studied by DFT simulations.

13.
J Cell Mol Med ; 22(7): 3638-3651, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29682889

RESUMO

We previously observed that disruption of FK506-binding protein 12.6 (FKBP12.6) gene resulted in cardiac hypertrophy in male mice. Studies showed that overexpression of FKBP12.6 attenuated thoracic aortic constriction (TAC)-induced cardiac hypertrophy in mice, whereas the adenovirus-mediated overexpression of FKBP12.6 induced hypertrophy and apoptosis in cultured neonatal cardiomyocytes, indicating that the role of FKBP12.6 in cardiac hypertrophy is still controversial. In this study, we aimed to investigate the roles and mechanisms of FKBP12.6 in angiotensin II (AngII)-induced cardiac hypertrophy using various transgenic mouse models in vivo and in vitro. FKBP12.6 knockout (FKBP12.6-/- ) mice and cardiac-specific FKBP12.6 overexpressing (FKBP12.6 TG) mice were infused with AngII (1500 ng/kg/min) for 14 days subcutaneously by implantation of an osmotic mini-pump. The results showed that FKBP12.6 deficiency aggravated AngII-induced cardiac hypertrophy, while cardiac-specific overexpression of FKBP12.6 prevented hearts from the hypertrophic response to AngII stimulation in mice. Consistent with the results in vivo, overexpression of FKBP12.6 in H9c2 cells significantly repressed the AngII-induced cardiomyocyte hypertrophy, seen as reductions in the cell sizes and the expressions of hypertrophic genes. Furthermore, we demonstrated that the protection of FKBP12.6 on AngII-induced cardiac hypertrophy was involved in reducing the concentration of intracellular Ca2+ ([Ca2+ ]i), in which the protein significantly inhibited the key Ca2+ /calmodulin-dependent signalling pathways such as calcineurin/cardiac form of nuclear factor of activated T cells 4 (NFATc4), calmodulin kinaseII (CaMKII)/MEF-2, AKT/Glycogen synthase kinase 3ß (GSK3ß)/NFATc4 and AKT/mTOR signalling pathways. Our study demonstrated that FKBP12.6 protects heart from AngII-induced cardiac hypertrophy through inhibiting Ca2+ /calmodulin-mediated signalling pathways.


Assuntos
Cálcio/metabolismo , Calmodulina/metabolismo , Cardiomegalia/metabolismo , Proteínas de Ligação a Tacrolimo/metabolismo , Angiotensina II/metabolismo , Angiotensina II/toxicidade , Animais , Calcineurina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/patologia , Linhagem Celular , Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas de Ligação a Tacrolimo/genética
14.
J Cell Mol Med ; 22(1): 101-110, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28816006

RESUMO

It has been recently reported that CD38 was highly expressed in adipose tissues from obese people and CD38-deficient mice were resistant to high-fat diet (HFD)-induced obesity. However, the role of CD38 in the regulation of adipogenesis and lipogenesis is unknown. In this study, to explore the roles of CD38 in adipogenesis and lipogenesis in vivo and in vitro, obesity models were generated with male CD38-/- and WT mice fed with HFD. The adipocyte differentiations were induced with MEFs from WT and CD38-/- mice, 3T3-L1 and C3H10T1/2 cells in vitro. The lipid accumulations and the alternations of CD38 and the genes involved in adipogenesis and lipogenesis were determined with the adipose tissues from the HFD-fed mice or the MEFs, 3T3-L1 and C3H10T1/2 cells during induction of adipocyte differentiation. The results showed that CD38-/- male mice were significantly resistant to HFD-induced obesity. CD38 expressions in adipocytes were significantly increased in WT mice fed with HFD, and the similar results were obtained from WT MEFs, 3T3-L1 and C3H10T1/2 during induction of adipocyte differentiation. The expressions of PPARγ, AP2 and C/EBPα were markedly attenuated in adipocytes from HFD-fed CD38-/- mice and CD38-/- MEFs at late stage of adipocyte differentiation. Moreover, the expressions of SREBP1 and FASN were also significantly decreased in CD38-/- MEFs. Finally, the CD38 deficiency-mediated activations of Sirt1 signalling were up-regulated or down-regulated by resveratrol and nicotinamide, respectively. These results suggest that CD38 deficiency impairs adipogenesis and lipogenesis through activating Sirt1/PPARγ-FASN signalling pathway during the development of obesity.


Assuntos
ADP-Ribosil Ciclase 1/deficiência , Adipogenia , Tecido Adiposo/metabolismo , Lipogênese , PPAR gama/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo , ADP-Ribosil Ciclase 1/metabolismo , Adipócitos/metabolismo , Animais , Diferenciação Celular , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Camundongos , NAD/metabolismo
15.
Cell Physiol Biochem ; 48(6): 2350-2363, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30114710

RESUMO

BACKGROUND/AIMS: Previous studies showed that CD38 deficiency protected heart from ischemia/reperfusion injury and high fat diet (HFD)-induced obesity in mice. However, the role of CD38 in HFD-induced heart injury remains unclear. In the present study, we have investigated the effects and mechanisms of CD38 deficiency on HFD-induced heart injury. METHODS: The metabolites in heart from wild type (WT) and CD38 knockout (CD38-/-) mice were examined using metabolomics analysis. Cell viability, lactate hydrogenase (LDH) release, super oxide dismutase (SOD) activity, reactive oxygen species (ROS) production, triglyceride concentration and gene expression were examined by biochemical analysis and QPCR. RESULTS: Our results revealed that CD38 deficiency significantly elevated the intracellular glutathione (GSH) concentration and GSH/GSSG ratio, decreased the contents of free fatty acids and increased intracellular NAD+ level in heart from CD38-/- mice fed with HFD. In addition, in vitro knockdown of CD38 significantly attenuated OA-induced cellular injury, ROS production and lipid synthesis. Furthermore, the expression of mitochondrial deacetylase Sirt3 as well as its target genes FOXO3 and SOD2 were markedly upregulated in the H9C2 cell lines after OA stimulation. In contrast, the expressions of NOX2 and NOX4 were significantly decreased in the cells after OA stimulation. CONCLUSION: Our results demonstrated that CD38 deficiency protected heart from HFD-induced oxidative stress via activating Sirt3/FOXO3-mediated anti-oxidative stress pathway.


Assuntos
ADP-Ribosil Ciclase 1/genética , Dieta Hiperlipídica , Proteína Forkhead Box O3/metabolismo , Glicoproteínas de Membrana/genética , Estresse Oxidativo , Sirtuína 3/metabolismo , ADP-Ribosil Ciclase 1/antagonistas & inibidores , ADP-Ribosil Ciclase 1/metabolismo , Animais , Linhagem Celular , Glutationa/metabolismo , Masculino , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Superóxido Dismutase/metabolismo
16.
Opt Express ; 26(13): 16585-16599, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119486

RESUMO

Sub-diffraction quasi-non-diffracting beams with sub-wavelength transverse size are attractive for applications such as optical nano-manipulation, optical nano-fabrication, optical high-density storage, and optical super-resolution microscopy. In this paper, we proposed an optimization-free design approach and demonstrated the possibility of generating sub-diffraction quasi-non-diffracting beams with sub-wavelength size for different polarizations by a binary-phase Fresnel planar lens. More importantly, the optimization-free method significantly simplifies the design procedure and the generation of sub-diffracting quasi-non-diffracting beams. Utilizing the concept of normalized angular spectrum compression, for wavelength λ0 = 632.8 nm, a binary-phase Fresnel planar lens was designed and fabricated. The experimental results show that the sub-diffraction transverse size and the non-diffracting propagation distances are 0.40λ0-0.54λ0 and 90λ0, 0.43λ0-0.54λ0 and 73λ0, and 0.34λ0-0.41λ0 and 80λ0 for the generated quasi-non-diffracting beams with circular, longitudinal, and azimuthal polarizations, respectively.

17.
Opt Express ; 26(7): 7866-7875, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29715761

RESUMO

A three-dimensional (3D) hollow spot is of great interest for a wide variety of applications such as microscopy, lithography, data storage, optical manipulation, and optical manufacturing. Based on conventional high-numerical-aperture objective lenses, various methods have been proposed for the generation of 3D hollow spots for different polarizations. However, conventional optics are bulky, costly, and difficult to integrate. More importantly, they are diffraction-limited in nature. Owing to their unique properties of small size, light weight, and ease of integration, planar lenses have become attractive as components in the development of novel optical devices. Utilizing the concept of super-oscillation, planar lenses have already shown great potential in the generation of sub-diffraction, or even of super-oscillatory features, in propagating optical waves. In this paper, we propose a binary-phase planar lens with an ultra-long focal length (300λ) for the generation of a 3D hollow spot with a cylindrical vector wave. In addition, we experimentally demonstrate the formation of such a hollow spot with a sub-diffraction transverse size of 0.546λ (smaller than the diffraction limit of 0.5λ/NA, where NA denotes the lens numerical aperture) and a longitudinal size of 1.585λ. The ratio of central minimum intensity to the central ring peak intensity is less than 3.7%. Such a planar lens provides a promising way to achieve tight 3D optical confinement for different uses that might find applications in super-resolution microscopy, nano-lithography, high-density data storage, nano-particle optical manipulation, and nano-optical manufacturing.

18.
Opt Express ; 26(11): 14132-14142, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29877456

RESUMO

Terahertz wave imaging offers promising properties for non-destructive testing applications in the areas of homeland security, medicine, and industrial inspection. However, conventional optical lenses are heavy and bulky and difficult to integrate. An all-dielectric metasurface provides an attractive way to realize a planar lens of light weight that is ultrathin and offers ease of integration. Terahertz lenses based on various metasurfaces have been studied, especially for the application of wave focusing, while there are few experimental demonstrations of terahertz wave imaging lenses based on an all-dielectric metasurface. In the present work, we propose a metalens based on an all-dielectric metasurface with a sub-wavelength unit size of 0.39λ for terahertz wave imaging and experimentally demonstrate its performance in focusing and imaging. A large numerical aperture metalens was fabricated with a focal length of 300λ, radius of 300λ, and numerical aperture of 0.707. The experimental results show that the lens can focus THz waves with an incident angle up to 48°. More importantly, clear terahertz wave images of different objects were obtained for both different cases of forward- and inverse-incident directions, which demonstrate the reversibility of the metalens for imaging. Such a metalens provides a way for realization of all-planar-lens THz imaging system, and might find application in terahertz wave imaging, information processing, microscopy, and others.

19.
Toxicol Appl Pharmacol ; 356: 182-190, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30125596

RESUMO

Taurine-magnesium coordination compound (TMCC) exhibits antiarrhythmic effects in cesium-chloride-and ouabain-induced arrhythmias; however, the mechanism underlying these effects on arrhythmia remains poorly understood. Here, we investigated the effects of TMCC on aconitine-induced arrhythmia in vivo and the electrophysiological effects of this compound in rat ventricular myocytes in vitro. Aconitine was used to induce arrhythmias in rats, and the dosages required to produce ventricular premature contraction (VPC), ventricular tachycardia (VT), ventricular fibrillation (VF), and cardiac arrest (CA) were recorded. Additionally, the sodium current (INa) and L-type calcium current (ICa,L) were analyzed in normal and aconitine-treated ventricular myocytes using whole-cell patch-clamp recording. In vivo, intravenous administration of TMCC produced marked antiarrhythmic effects, as indicated by the increased dose of aconitine required to induce VPC, VT, VF, and CA. Moreover, this effect was abolished by administration of sodium channel opener veratridine and calcium channel agonist Bay K8644. In vitro, TMCC inhibited aconitine-induced increases in INa and ICa,L. These results revealed that TMCC inhibited aconitine-induced arrhythmias through effects on INa and ICa,L.


Assuntos
Aconitina , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/tratamento farmacológico , Canais Iônicos/efeitos dos fármacos , Compostos de Magnésio/uso terapêutico , Taurina/uso terapêutico , Animais , Canais de Cálcio Tipo L/efeitos dos fármacos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Feminino , Parada Cardíaca/induzido quimicamente , Parada Cardíaca/prevenção & controle , Ventrículos do Coração/citologia , Ventrículos do Coração/efeitos dos fármacos , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Canais de Sódio/efeitos dos fármacos
20.
Mediators Inflamm ; 2018: 8736949, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977153

RESUMO

CD38 was first identified as a lymphocyte-specific antigen and then has been found to be widely expressed in a variety of cell types. The functions of CD38 are involved in numerous biological processes including immune responses. Here, we showed the downregulations of both TLR2 mRNA and protein in macrophages from CD38-/- mice and in CD38 knockdown RAW264.7 cells. Several NF-κB-binding motifs in the promoter region of the TLR2 gene were identified by the bioinformatics analysis and were confirmed by the luciferase activity assay with the different truncated TLR2 promoters. CD38 deficiency resulted in the reduction of NF-κB p65 and acetyl-NF-κB p65 (Ac-p65) levels as determined by Western blot. The expression of Sirt1 did not change, but an increased activity of Sirt1 was observed in CD38-deficient macrophages. Inhibition of the Sirt1/NF-κB signaling pathway resulted in downregulation of TLR2 expression in RAW264.7 cells. However, re-expression of CD38 in the knockdown clones reversed the effect on Sirt1/NF-κB/TLR2 signaling, which is NAD-dependent. Moreover, the inflammatory cytokines including G-CSF, IL-1alpha, IL-6, MCP-1, MIP-1alpha, and RANTES were increased in CD38 knockdown RAW264.7 cells. Taken together, our data demonstrated that CD38 deficiency enhances inflammatory response in macrophages, and the mechanism may be partly associated with increased Sirt1 activity, which promoted NF-κB deacetylation and then inhibited expression of the TLR2 gene. Obviously, our study may provide an insight into the molecular mechanisms in CD38-mediated inflammation.


Assuntos
ADP-Ribosil Ciclase 1/deficiência , Inflamação/metabolismo , Macrófagos Peritoneais/metabolismo , Macrófagos/metabolismo , NF-kappa B/metabolismo , Sirtuína 1/metabolismo , ADP-Ribosil Ciclase 1/genética , ADP-Ribosil Ciclase 1/metabolismo , Animais , Western Blotting , Biologia Computacional , Inflamação/genética , Camundongos , Células RAW 264.7 , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Sirtuína 1/genética , Receptor 2 Toll-Like/metabolismo
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