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1.
Cell Mol Life Sci ; 81(1): 204, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700532

RESUMO

The silent information regulator T1 (SIRT1) is linked to longevity and is a crucial mediator of osteoblast function. We investigated the direct role of Sirt1 during bone modeling and remodeling stages in vivo using Tamoxifen-inducible osteoblast-specific Sirt1 conditional knockout (cKO) mice. cKO mice exhibited lower trabecular and cortical bone mass in the distal femur. These phenotypes were coupled with lower bone formation and bone resorption. Metabolomics analysis revealed that the metabolites involved in glycolysis were significantly decreased in cKO mice. Further analysis of the quantitative acetylome revealed 11 proteins with upregulated acetylation levels in both the femur and calvaria of cKO mice. Cross-analysis identified four proteins with the same upregulated lysine acetylation site in both the femur and calvaria of cKO mice. A combined analysis of the metabolome and acetylome, as well as immunoprecipitation, gene knockout, and site-mutation experiments, revealed that Sirt1 deletion inhibited glycolysis by directly binding to and increasing the acetylation level of Glutamine oxaloacetic transaminase 1 (GOT1). In conclusion, our study suggested that Sirt1 played a crucial role in regulating osteoblast metabolism to maintain bone homeostasis through its deacetylase activity on GOT1. These findings provided a novel insight into the potential targeting of osteoblast metabolism for the treatment of bone-related diseases.


Assuntos
Glicólise , Homeostase , Camundongos Knockout , Osteoblastos , Sirtuína 1 , Animais , Camundongos , Acetilação , Osso e Ossos/metabolismo , Fêmur/metabolismo , Osteoblastos/metabolismo , Osteogênese , Sirtuína 1/metabolismo , Sirtuína 1/genética
2.
Curr Issues Mol Biol ; 46(6): 5866-5880, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38921021

RESUMO

Avian leukosis virus (ALV) is an avian oncogenic retrovirus that can impair immunological function, stunt growth and decrease egg production in avian flocks. The capsid protein (P27) is an attractive candidate for ALV diagnostics. In the present study, a new hybridoma cell (1F8) stably secreting an anti-P27 monoclonal antibody (mAb) was developed. The mAb exhibited a high affinity constant (Ka) of 8.65 × 106.0 L/mol, and it could be used for the detection of ALV-A/B/J/K strains. Moreover, a total of eight truncated recombinant proteins and five synthetic polypeptides were utilized for the identification of the B-cell epitopes present on P27. The results revealed that 218IIKYVLDRQK227 was the minimal epitope recognized by 1F8, which had never been reported before. Additionally, the epitopes could strongly react with different ALV subgroup's specific positive serum and had a complete homology among all the ALV subgroups strains. Finally, a new sandwich ELISA method was created for the detection of ALV antigens, demonstrating increased sensitivity compared to a commercially available ELISA kit. These results offer essential knowledge for further characterizing the antigenic composition of ALV P27 and will facilitate the development of diagnostic reagents for ALV.

3.
Opt Express ; 32(11): 18997-19005, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859044

RESUMO

In this work, a double-end diffusion bonded Nd:YVO4 self-Raman laser was designed to drive an intracavity, noncritically-phase-matched KTiOAsO4 (KTA) optical parametric oscillator (OPO). Both conversion efficiency and output power at 1.7 µm (the wavelength of the OPO signal field) were improved by effectively reducing the thermal lens effect and increasing the effective length of self-Raman medium. At an incident pump power of 15.4 W, the output power for 1742 nm output laser reached 2.16 W with a conversion efficiency of 14%, and the output having a pulse width of 10.5 ns and a pulse repetition frequency of 90 kHz. The competition between the OPO and cascaded Raman laser was observed when the incident pump power was above 12.4 W. The results highlight that in order to improve output power at 1742 nm, it is critical that both the cascaded, second-Stokes field at 1313 nm and the signal field generated at 1534 nm from the 1064 nm field driving the KTA-OPO be minimized, if not completely suppressed. This laser system combining the processes of stimulated Raman scattering and optical parametric oscillation for the generation of laser emission at 1742 nm may find significant application across a broad range of fields including biological engineering, laser therapy, optical coherence tomography and for the generation of mid-infrared laser wavelengths.

4.
J Org Chem ; 89(2): 1301-1309, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38176055

RESUMO

An efficient approach for the preparation of tetracyclic indeno[1,2-b]indoles via Rh(III)-catalyzed C-H cascade annulation between arylhydrazines and diazo indan-1,3-diones has been established. In addition, a series of indeno[1,2-b]indoles were obtained in up to 96% yield with a wide range of substrates and high functional group tolerance. Finally, the diverse transformations of the desired products demonstrate the synthetic utility and utilization of this protocol.

5.
Bioorg Chem ; 146: 107274, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503026

RESUMO

The inhibition of transforming growth factor-ß1 (TGF-ß1) signaling by targeting TGF-ß receptor 1 (TßR1) has been considered as an ideal approach for the prevention of pancreatic cancer metastasis. Utilizing a pharmacophore model for TßR1 inhibitors, candidate compounds with the potential TßR1 binding ability were screened from the U.S. Food and Drug Administration (FDA) database, and riboflavin (RF) with a highest fit value was chosen to investigate its binding ability to TßR1 and effect on TGF-ß1 signaling in pancreatic cancer cells. Molecular docking and cellular thermal shift assay (CETSA) proved that RF at pharmacological concentrations could directly bind to TßR1. Further studies showed that pharmacological concentrations of RF in vitro could block TGF-ß1 signaling, suppress the migration and invasion, and prevent epithelial-mesenchymal transition (EMT) process of pancreatic cancer cells in the absence or presence of TGF-ß1 stimulation, indicating that RF presented anti-metastatic effect in pancreatic cancer cells. Knockdown of TßR1 could significantly attenuate the effects of RF on the migration and EMT process in pancreatic cancer cells, further confirming that the anti-metastatic effect of RF was achieved by blocking TGF-ß1 signaling after binding to TßR1. Moreover, in a mouse model of pancreatic cancer metastasis, it was certified that RF administration could block lung and liver metastases, TGF-ß1 signaling and EMT process of pancreatic cancer in vivo. In summary, our findings showed that RF could block TGF-ß1 signaling by directly binding to TßR1, thereby suppressing the metastasis of pancreatic cancer cells by inhibiting EMT process both in vitro and in vivo.


Assuntos
Neoplasias Pancreáticas , Fator de Crescimento Transformador beta1 , Animais , Camundongos , Fator de Crescimento Transformador beta1/metabolismo , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Invasividade Neoplásica/prevenção & controle , Neoplasias Pancreáticas/tratamento farmacológico , Receptores de Fatores de Crescimento Transformadores beta , Transição Epitelial-Mesenquimal
6.
Sensors (Basel) ; 24(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931655

RESUMO

The Jing-Mi Diversion Canal is a large-scale water diversion project in Beijing. Routine monitoring is crucial for the reliability and stability of urban water supply. Compared with traditional monitoring methods, interferometric synthetic aperture radar (InSAR) has the advantages of large scale and high accuracy. Based on the small baseline subset InSAR, 187 ascending and 102 descending SAR images obtained from Sentinel-1 were used to detect the deformation along the diversion canal from 2017 to 2023. The results show that there was a sinking trend along the diversion canal. The subsidence was serious in the first half of the canal, and continued to sink from 2019 to 2020. The subsidence was alleviated in 2023. Combined with leveling measurements, the InSAR deformation monitoring results of important pumping station buildings were verified. The measurement accuracy of InSAR can reach the millimeter level. We extracted the groundwater level time series and subsidence for risky canal segments. Through pixel-by-pixel comparison, it was found that fluctuations in groundwater level would have some impact on surface deformation. Severe local subsidence or uplift deformation occasionally occurred. To ensure the safety of water diversion, the monitoring and maintenance of relevant pump station buildings in risky areas should be increased in the future.

7.
Molecules ; 29(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611943

RESUMO

Luteolin-7-O-ß-d-glucuronide (LGU) is a major active flavonoid glycoside compound that is extracted from Ixeris sonchifolia (Bge.) Hance, and it is a Chinese medicinal herb mainly used for the treatment of coronary heart disease, angina pectoris, cerebral infarction, etc. In the present study, the neuroprotective effect of LGU was investigated in an oxygen glucose deprivation (OGD) model and a middle cerebral artery occlusion (MCAO) rat model. In vitro, LGU was found to effectively improve the OGD-induced decrease in neuronal viability and increase in neuronal death by a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) leakage rate assay, respectively. LGU was also found to inhibit OGD-induced intracellular Ca2+ overload, adenosine triphosphate (ATP) depletion, and mitochondrial membrane potential (MMP) decrease. By Western blotting analysis, LGU significantly inhibited the OGD-induced increase in expressions of receptor-interacting serine/threonine-protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL). Moreover, molecular docking analysis showed that LGU might bind to RIP3 more stably and firmly than the RIP3 inhibitor GSK872. Immunofluorescence combined with confocal laser analyses disclosed that LGU inhibited the aggregation of MLKL to the nucleus. Our results suggest that LGU ameliorates OGD-induced rat primary cortical neuronal injury via the regulation of the RIP3/MLKL signaling pathway in vitro. In vivo, LGU was proven, for the first time, to protect the cerebral ischemia in a rat middle cerebral artery occlusion (MCAO) model, as shown by improved neurological deficit scores, infarction volume rate, and brain water content rate. The present study provides new insights into the therapeutic potential of LGU in cerebral ischemia.


Assuntos
Lesões Encefálicas , Glucuronídeos , Luteolina , Animais , Ratos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Simulação de Acoplamento Molecular , Transdução de Sinais , Proteínas Quinases
8.
Opt Express ; 31(12): 20150-20159, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381415

RESUMO

The tilted fiber Bragg grating (TFBG) with dense comb-like resonances offers a promising fiber-optic sensing platform but could suffer from cross sensitivity dependent on bulk and surface environment. In this work, the decoupling of bulk and surface characteristics (indicated by bulk refractive index (RI) and surface-localized binding film) from each other is attained theoretically with a bare TFBG sensor. This is realized with the proposed decoupling approach based on differential spectral responses of cut-off mode resonance and mode dispersion represented as wavelength interval between P- and S-polarized resonances of the TFBG to the bulk RI and surface film thickness. The results demonstrate that with this method the sensing performance for decoupling bulk RI and surface film thickness is comparative to the cases in which either the bulk or surface environment of the TFBG sensor changes, with the bulk and surface sensitivities over 540 nm/RIU and 12 pm/nm, respectively.

9.
Chemistry ; 29(48): e202301575, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37306241

RESUMO

Manipulating the radical concentration to modulate the properties in solid multifunctional materials is an attractive topic in various frontier fields. Viologens have the unique redox capability to generate radical states through reversible electron transfer (ET) under external stimuli. Herein, taking the viologens as the model, two kinds of crystalline compounds with different molecule-conjugated systems were designed and synthesized. By subjecting the specific model viologens to pressure, the cross-conjugated 2-X all exhibit much higher radical concentrations, along with more sensitive piezochromic behaviors, compared to the linear-conjugated 1-X. Unexpectedly, we find that the electrical resistance (R) of 1-NO3 decreased by three orders of magnitude with the increasing pressure, while that in high-radical-concentration 2-NO3 remained almost unchanged. To date, such unusual invariant conductivity has not been documented in molecular-based materials under high pressure, breaking the conventional wisdom that the generations of radicals are beneficial to improve conductivity. We highlight that adjusting the molecular conjugation modes can be used as an effective way to regulate the radical concentrations and thus modulate properties rationally.

10.
Chemistry ; 29(62): e202302397, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37583100

RESUMO

Inkless and erasable printing (IEP) based on chromic materials holds great promise to alleviate environmental and sustainable problems. Metal-organic polymers (MOPs) are bright platforms for constructing IEP materials. However, it is still challenging to design target MOPs with excellent specific functions rationally due to the intricate component-structure-property relationships. Herein, an effective strategy was proposed for the rational design IEP-MOP materials. The stimuli-responsive viologen moiety was introduced into the construction of MOPs to give it potential chromic behaviors and two different coordination models (i. e. bilateral coordination model, M1 ; unilateral coordinated model, M2 ) based on the same viologen ligand were designed. Aided by theoretical calculations, model M1 was recommended secondarily as a more suitable system for IEP materials. Along this line, two representative viologen-ZnII MOPs 1 and 2 with models M1 and M2 were synthesized successfully. Experiments exhibit that 1 does have quicker stimuli response, stronger color contrast and longer radical lifetime compared to 2. Significantly, the obtained 1-IEP media brightly inherits the excellent chromic characteristics of 1 and the flexibility of the paper at the same time, which achieves most daily printing requirements, as well as enough resolution and durability to be used in identification by smart device.

11.
Theor Appl Genet ; 136(5): 97, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37027047

RESUMO

KEY MESSAGE: AhyHOF1, likely encoding a WRI1 transcription factor, plays critical roles in peanut oil synthesis. Although increasing the oil content of peanut to meet growing demand has long been a primary aim of breeding programs worldwide, the mining of genetic resources to achieve this objective has obviously lagged behind that of other oil crops. In the present study, we developed an advanced recombinant inbred line population containing 192 F9:11 families derived from parents JH5 and KX01-6. We then constructed a high-resolution genetic map covering 3,706.382 cM, with an average length of 185.32 cM per linkage group, using 2840 polymorphic SNPs. Two stable QTLs, qCOA08_1 and qCOA08_2 having the highest contributions to genetic variation (16.1% and 20.7%, respectively), were simultaneously detected in multiple environments and closely mapped within physical intervals of approximately 2.9 Mb and 1.7 Mb, respectively, on chromosome A08. In addition, combined analysis of whole-genome and transcriptome resequencing data uncovered a strong candidate gene encoding a WRI1 transcription factor and differentially expressed between the two parents. This gene, designated as High Oil Favorable gene 1 in Arachis hypogaea (AhyHOF1), was hypothesized to play roles in oil accumulation. Examination of near-inbred lines of #AhyHOF1/#Ahyhof1 provided further evidence that AhyHOF1 increases oil content, mainly by affecting the contents of several fatty acids. Taken together, our results provide valuable information for cloning the favorable allele for oil content in peanut. In addition, the closely linked polymorphic SNP markers within qCOA08_1 and qCOA08_2 loci may be useful for accelerating marker-assisted selection breeding of peanut.


Assuntos
Arachis , Melhoramento Vegetal , Humanos , Arachis/genética , Mapeamento Cromossômico/métodos , Locos de Características Quantitativas , Fatores de Transcrição/genética
12.
Virol J ; 20(1): 151, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452371

RESUMO

Pseudorabies virus (PRV) can infect multiple hosts and lead to fatal encephalitis. There is a significant increase in the number of microglia in the brain of animals infected with PRV. However, whether and how microglia contribute to central nervous system damage in PRV infection remain unknown. In the present study, we elucidated that PRV infection can cause more severe inflammatory cell infiltration, thicker and more numerous vessel sleeve walls, and more severe inflammatory responses in the brains of natural hosts (pigs) than in those of nonnatural hosts (mice). In a mice infection model, activated microglia restricted viral replication in the early stage of infection. Acute neuroinflammation caused by microglia hyperactivation at late-stage of infection. Furthermore, in vitro experiments revealed that microglia restricted viral replication and decreased viral infectivity. This may be associated with the phagocytic ability of microglia because we observed a significant increase in the expression of the membrane receptor TREM2 in microglia, which is closely related to phagocytosis, we observed that depletion of microglia exacerbated neurological symptoms, blood-brain barrier breakdown, and peripheral lymphocyte infiltration. Taken together, we revealed the dual role of microglia in protecting the host and neurons from PRV infection.


Assuntos
Herpesvirus Suídeo 1 , Pseudorraiva , Camundongos , Animais , Suínos , Microglia , Encéfalo , Imunidade
13.
Org Biomol Chem ; 21(10): 2096-2100, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36809537

RESUMO

A Rh(III)-catalyzed C-H bond direct alkylation between 2-arylphthalazine-1,4-diones and α-Cl ketones, which are sp3-carbon synthons, under mild conditions has been disclosed. The corresponding phthalazine derivatives are readily obtained in moderate to excellent yields with a wide range of substrates and high functional group tolerance. The practicality and utility of this method are demonstrated by the derivatization of the product.

14.
Arch Biochem Biophys ; 731: 109448, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36306919

RESUMO

Alzheimer's disease (AD), a common neurodegenerative disease, is characterised by the deposition of amyloid-ß (Aß) plaques and neurofibrillary tangles. An increasing number of studies have demonstrated that Aß causes neuronal damage and mitochondrial dysfunction. Herein, we evaluated the neuroprotective effect of sodium butyrate (NaB) against Aß induced neurotoxicity in PC12 cells. The results revealed that 3 mM of NaB promoted the expression of angiotensin-converting enzyme and brain-derived neurotrophic factor, which exert a neuroprotective effect by activating G protein-coupled receptors. Moreover, NaB could significantly improve mitochondrial dysfunction caused by Aß. In conclusion, NaB protected PC12 cells from Aß-induced cell damage, highlighting the potential of NaB in AD treatment.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Animais , Ratos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/toxicidade , Peptídeos beta-Amiloides/metabolismo , Antioxidantes/metabolismo , Apoptose , Ácido Butírico/farmacologia , Sobrevivência Celular , Potencial da Membrana Mitocondrial , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Fragmentos de Peptídeos/toxicidade , Fragmentos de Peptídeos/metabolismo
15.
FASEB J ; 34(1): 1412-1429, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31914599

RESUMO

Accumulation of amyloid ß (Aß) peptide, inflammation, and oxidative stress contribute to Alzheimer's disease (AD) and trigger complex pathogenesis. The ketone body ß-hydroxybutyrate (BHBA) is an endogenous metabolic intermediate that protects against stroke and neurodegenerative diseases, but the underlying mechanisms are unclear. The present study aims to elucidate the protective effects of BHBA in the early stage of AD model and investigate the underlying molecular mechanisms. Three-and-half-month-old double-transgenic mice (5XFAD) overexpressing ß-amyloid precursor protein (APP) and presenilin-1 (PS1) were used as the AD model. The 5XFAD mice received 1.5 mmol/kg/d BHBA subcutaneously for 28 days. Morris water maze test, nest construction, and passive avoidance experiments were performed to assess the therapeutic effects on AD prevention in vivo, and brain pathology of 5XFAD mice including amyloid plaque deposition and microglia activation were assessed. Gene expression profiles in the cortexes of 5XFAD- and BHBA-treated 5XFAD mice were performed with high-throughput sequencing and bioinformatic analysis. Mouse HT22 cells were treated with 2 mM BHBA to explore its in vitro protective effects of BHBA on hippocampal neurons against Aß oligomer toxicity, ATP production, ROS generation, and mitochondrial aerobic respiratory function. APP, BACE1, and neprilysin (NEP) expression levels were evaluated in HT22 cells following treatment with BHBA by measuring the presence or absence of G protein-coupled receptor 109A (GPR109A). BHBA improved cognitive function of 5XFAD mice in Morris water maze test, nesting construction and passive avoidance experiments, and attenuated Aß accumulation and microglia overactivation in the brain. BHBA also enhanced mitochondrial respiratory function of hippocampal neurons and protected it from Aß toxicity. The enzymes, APP and NEP were regulated by BHBA via G-protein-coupled receptor 109A (GPR109A). Furthermore, RNA sequencing revealed that BHBA-regulated genes mainly annotated in aging, immune system, nervous system, and neurodegenerative diseases. Our data suggested that BHBA confers protection against the AD-like pathological events in the AD mouse model by targeting multiple aspects of AD and it may become a promising candidate for the prevention and treatment of AD.


Assuntos
Ácido 3-Hidroxibutírico/farmacologia , Doença de Alzheimer/tratamento farmacológico , Cognição/efeitos dos fármacos , Hipocampo/metabolismo , Neurônios/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipocampo/patologia , Camundongos , Camundongos Transgênicos , Neurônios/patologia
16.
Opt Express ; 28(23): 34104-34110, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182887

RESUMO

We demonstrate an all-fiber, thulium-doped, mode-locked laser using a black phosphorus (BP) saturable absorber (SA). The BP-SA, exhibiting strong nonlinear response, is fabricated by inkjet printing. The oscillator generates self-starting 139 fs dispersion-managed soliton pulses centered at 1859nm with 55.6 nm spectral bandwidth. This is the shortest pulse duration and widest spectral bandwidth achieved directly from an all-fiber thulium-doped fiber laser mode-locked with a nanomaterial saturable absorber to date. Our findings demonstrate the applicability of BP for femtosecond pulse generation at 2 µm spectral region.

17.
Opt Express ; 28(5): 6937-6944, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32225931

RESUMO

We numerically and experimentally demonstrate the generation of broad bandwidth mode-locked dual-wavelength pulses with diverse-pattern from a dispersion managed erbium-doped (Er-doped) fiber laser. The two-peak gain profile of the Er-doped fiber is shown to have advantages in achieving broadband dual-wavelength pulses compared to a comb filter in our cavity. Our obtained bandwidths of 24 nm and 11.5 nm represent the broadest achieved in an Er-doped dual-wavelength fiber laser to date. In addition, the weak third-order dispersion (TOD) of the fibers facilitates two dispersion-pattern pulses (one stretched pulse and one dissipative soliton) generated in the near zero dispersion regime. Our results provide a convenient, effective way to obtain such sources for potential applications, such as in dual-comb metrology and multicolor pulses in nonlinear microscopy.

18.
J Biol Chem ; 293(22): 8614-8625, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29653943

RESUMO

The NAD+-dependent deacetylase sirtuin-1 (SIRT1) has emerged as an important regulator of chondrogenesis and cartilage homeostasis, processes that are important for physiological skeletal growth and that are dysregulated in osteoarthritis. However, the functional role and underlying mechanism by which SIRT1 regulates chondrogenesis remain unclear. Using cultured rat metatarsal bones and chondrocytes isolated from rat metatarsal rudiments, here we studied the effects of the SIRT1 inhibitor EX527 or of SIRT1 siRNA on chondrocyte proliferation, hypertrophy, and apoptosis. We show that EX527 or SIRT1 siRNA inhibits chondrocyte proliferation and hypertrophy and induces apoptosis. We also observed that SIRT1 inhibition mainly induces the PERK-eIF-2α-CHOP axis of the endoplasmic reticulum (ER) stress response in growth-plate chondrocytes. Of note, EX527- or SIRT1 siRNA-mediated inhibition of metatarsal growth and growth-plate chondrogenesis were partly neutralized by phenylbutyric acid, a chemical chaperone that attenuates ER stress. Moreover, EX527-mediated impairment of chondrocyte function (i.e. of chondrocyte proliferation, hypertrophy, and apoptosis) was partly reversed in CHOP-/- cells. We also present evidence that SIRT1 physically interacts with and deacetylates PERK. Collectively, our findings indicate that SIRT1 deacetylates PERK and attenuates the PERK-eIF-2α-CHOP axis of the unfolded protein response pathway and thereby promotes growth-plate chondrogenesis and longitudinal bone growth.


Assuntos
Condrócitos/citologia , Condrogênese , Fator de Iniciação 2 em Eucariotos/metabolismo , Sirtuína 1/metabolismo , Fator de Transcrição CHOP/metabolismo , Resposta a Proteínas não Dobradas , eIF-2 Quinase/metabolismo , Acetilação , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Condrócitos/metabolismo , Estresse do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/genética , Lâmina de Crescimento/citologia , Lâmina de Crescimento/metabolismo , Ratos , Ratos Sprague-Dawley , Sirtuína 1/genética , Fator de Transcrição CHOP/genética , eIF-2 Quinase/genética
19.
Plant Mol Biol ; 99(3): 283-298, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30623274

RESUMO

KEY MESSAGE: Methane-triggered lateral root formation is not only a universal event, but also dependent on L-cysteine desulfhydrase-dependent hydrogen sulfide signaling. Whether or how methane (CH4) triggers lateral root (LR) formation has not been elucidated. In this report, CH4 induction of lateral rooting and the role of hydrogen sulfide (H2S) were dissected in tomato and Arabidopsis by using physiological, anatomical, molecular, and genetic approaches. First, we discovered that CH4 induction of lateral rooting is a universal event. Exogenously applied CH4 not only triggered tomato lateral rooting, but also increased activities of L-cysteine desulfhydrase (DES; a major synthetic enzyme of H2S) and induced endogenous H2S production, and contrasting responses were observed in the presence of hypotaurine (HT; a scavenger of H2S) or DL-propargylglycine (PAG; an inhibitor of DES) alone. CH4-triggered lateral rooting were sensitive to the inhibition of endogenous H2S with HT or PAG. The changes in the transcripts of representative cell cycle regulatory genes, miRNA and its target genes were matched with above phenotypes. In the presence of CH4, Arabidopsis mutant Atdes1 exhibited defects in lateral rooting, compared with the wild-type. Molecular evidence showed that the transcriptional profiles of representative target genes modulated by CH4 in wild-type plants were impaired in Atdes1 mutant. Overall, our data demonstrate the main branch of the DES-dependent H2S signaling cascade in CH4-triggered LR formation.


Assuntos
Cistationina gama-Liase/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Sulfeto de Hidrogênio/metabolismo , Metano/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Cistationina gama-Liase/genética , Genes de Plantas/genética , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , MicroRNAs/genética , Mutação , Proteínas de Plantas/genética , Raízes de Plantas/citologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transcriptoma
20.
Dig Dis Sci ; 64(11): 3291-3299, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31079261

RESUMO

BACKGROUND: The epidemiology of upper gastrointestinal (L4) Crohn's disease in China remains poorly characterized. AIMS: We aimed to identify the clinical characteristics of L4 disease and clarify the relationship between disease characteristics at diagnosis and early outcomes. METHODS: We retrospectively enrolled 246 patients diagnosed between 2013 and 2017 and followed up for > 1 year post-diagnosis. Primary outcomes included the 1-year rates of hospitalization and abdominal surgery according to disease location and behavior. RESULTS: Of 80 patients with L4 disease (61, 25, and 18 with esophagogastroduodenal, jejunal, and proximal ileal involvement, respectively), none had granuloma, whereas 66.7%, 50%, 46.9%, 75%, and 70% had disease-specific endoscopic lesions in the esophagus, stomach, duodenum, jejunum, and proximal ileum, respectively. Compared to non-L4 disease, L4 disease was associated with higher rates of abdominal surgery (41.3% vs. 11.4%, P < 0.001) but similar rates of hospitalization within 1 year post-diagnosis. In L4 disease, jejunal and proximal ileal involvement was associated with stricturing behavior (P = 0.034, P < 0.001) and higher abdominal surgery rate (both: P < 0.001). Risk factors for abdominal surgery within 1 year post-diagnosis included age ≥ 40 years (OR 1.920; 95% CI 1.095-3.367), L4 phenotype (OR 6.335; 95% CI 3.862-10.390), stricturing disease (OR 3.162; 95% CI 1.103-9.866), and penetrating disease (OR 11.504; 95% CI 3.409-38.825), whereas the protective factor was female sex (OR 0.214; 95% CI 0.123-0.373). CONCLUSIONS: Early outcomes are worse for L4 than for non-L4 disease. Jejunoileum involvement predicts stricturing disease and early surgery. More aggressive initial therapy is needed to improve L4-disease prognosis.


Assuntos
Doença de Crohn/diagnóstico , Doença de Crohn/epidemiologia , Fenótipo , Trato Gastrointestinal Superior/patologia , Adolescente , Adulto , China/epidemiologia , Estudos de Coortes , Doença de Crohn/genética , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Adulto Jovem
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