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1.
Chem Res Toxicol ; 37(4): 620-632, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484110

RESUMO

As a vital micronutrient, zinc is integral to the structure, function, and signaling networks of diverse proteins. Dysregulated zinc levels, due to either excess intake or deficiency, are associated with a spectrum of health disorders. In this context, understanding zinc-regulated biological processes at the molecular level holds significant relevance to public health and clinical practice. Identifying and characterizing zinc-regulated proteins in their diverse proteoforms, however, remain a difficult task in advancing zinc biology. Herein, we address this challenge by developing a quantitative chemical proteomics platform that globally profiles the reactivities of proteinaceous cysteines upon cellular zinc depletion. Exploiting a protein-conjugated resin for the selective removal of Zn2+ from culture media, we identify an array of zinc-sensitive cysteines on proteins with diverse functions based on their increased reactivity upon zinc depletion. Notably, we find that zinc regulates the enzymatic activities, post-translational modifications, and subcellular distributions of selected target proteins such as peroxiredoxin 6 (PRDX6), platelet-activating factor acetylhydrolase IB subunit alpha1 (PAFAH1B3), and phosphoglycerate kinase (PGK1).


Assuntos
Cisteína , Zinco , Cisteína/química , Zinco/metabolismo , Proteínas/química
2.
Clin Exp Dermatol ; 48(2): 89-95, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36730499

RESUMO

BACKGROUND: Mycobacterium marinum is a nontuberculous mycobacterium and a conditional pathogen to humans, which can be inoculated directly and cause chronic skin granulomas. Dermoscopy has been applied to other granulomatous skin diseases, but not to M. marinum infection. AIM: To explore the dermoscopic features of M. marinum infection, and its correlation with clinical and histopathological features. METHODS: In total, 27 lesions from 27 patients (19 women, 8 men, age range 28-71 years) diagnosed with M. marinum infection were identified by clinical examination, histopathological results, PCR sequencing and mycobacterial culture in the dermatology outpatient department of our hospital from March 2020 to February 2022. The dermoscopy images and pathological characteristics were analysed. RESULTS: Lesions were located on the hands, forearms and upper arms. The following dermoscopic features were observed: yellowish-orange structureless areas (85·2%), white striped structures (59·3%), follicular plugs (29·6%), yellowish oval clods (14·8%) and reddish or pinkish areas (14·8%). Vessel structures were visible in all cases: long hairpin vessels (81·5%), corkscrew vessels (25·9%), comma-shaped vessels (22·2%) and linear vessels (22·2%). CONCLUSION: Yellowish-orange structureless areas, white striped structures and long hairpin vessels are the most common dermoscopic features of M. marinum infection. Thus, dermoscopy could be used as a noninvasive auxiliary diagnostic method to provide a diagnostic basis for this disease.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Neoplasias Cutâneas , Masculino , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Dermoscopia , Infecções por Mycobacterium não Tuberculosas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Micobactérias não Tuberculosas
3.
Nano Lett ; 21(7): 2738-2744, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33783214

RESUMO

Aqueous rechargeable zinc ion batteries are promising candidates for grid-scale applications owing to their low cost and high safety. However, they are plagued by the lack of suitable cathode and anode materials. Herein, we report on potassium vanadate (KVO) nanobelts as a promising cathode for an aqueous zinc ion battery, which shows a high discharge capacity of 461 mA h g-1 at 0.2 A g-1 and exhibits a capacity retention of 96.2% over 4000 cycles at 10 A g-1. Furthermore, to enhance the energy efficiency in an aqueous zinc ion battery, a facile and effective method on the anode is demonstrated. The energy efficiency increases from 47.5% for Zn//KVO coupled with the zinc foil anode to 66.5% for AB-Zn//KVO coupled with an acetylene black film improved zinc foil anode at 10 A g-1. The remarkable electrochemical performance makes AB-Zn//KVO a strong candidate for a high-performance aqueous zinc ion battery.

4.
J Cell Mol Med ; 25(7): 3585-3600, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33751819

RESUMO

Obesity is associated with biological dysfunction in skeletal muscle. As a condition of obesity accompanied by muscle mass loss and physical dysfunction, sarcopenic obesity (SO) has become a novel public health problem. Human fibroblast growth factor 19 (FGF19) plays a therapeutic role in metabolic diseases. However, the protective effects of FGF19 on skeletal muscle in obesity and SO are still not completely understood. Our results showed that FGF19 administration improved muscle loss and grip strength in young and aged mice fed a high-fat diet (HFD). Increases in muscle atrophy markers (FOXO-3, Atrogin-1, MuRF-1) were abrogated by FGF19 in palmitic acid (PA)-treated C2C12 myotubes and in the skeletal muscle of HFD-fed mice. FGF19 not only reduced HFD-induced body weight gain, excessive lipid accumulation and hyperlipidaemia but also promoted energy expenditure (PGC-1α, UCP-1, PPAR-γ) in brown adipose tissue (BAT). FGF19 treatment restored PA- and HFD-induced hyperglycaemia, impaired glucose tolerance and insulin resistance (IRS-1, GLUT-4) and mitigated the PA- and HFD-induced decrease in FNDC-5/irisin expression. However, these beneficial effects of FGF19 on skeletal muscle were abolished by inhibiting AMPK, SIRT-1 and PGC-1α expression. Taken together, this study suggests that FGF19 protects skeletal muscle against obesity-induced muscle atrophy, metabolic derangement and abnormal irisin secretion partially through the AMPK/SIRT-1/PGC-α signalling pathway, which might be a potential therapeutic target for obesity and SO.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Fatores de Crescimento de Fibroblastos/fisiologia , Fibronectinas/metabolismo , Atrofia Muscular/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 1/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Animais , Linhagem Celular , Dieta Hiperlipídica , Fatores de Crescimento de Fibroblastos/farmacologia , Hiperglicemia/metabolismo , Hiperlipidemias/metabolismo , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Transdução de Sinais
5.
J Am Chem Soc ; 143(48): 20332-20342, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34817176

RESUMO

Chemoproteomic profiling of cysteines has emerged as a powerful method for screening the proteome-wide targets of cysteine-reactive fragments, drugs, and natural products. Herein, we report the development and an in-depth evaluation of a tetrafluoroalkyl benziodoxole (TFBX) as a cysteine-selective chemoproteomic probe. We show that this probe features numerous key improvements compared to the traditionally used cysteine-reactive probes, including a superior target occupancy, faster labeling kinetics, and broader proteomic coverage, thus enabling profiling of cysteines directly in live cells. In addition, the fluorine "signature" of probe 7 constitutes an additional advantage resulting in a more confident adduct-amino acid site assignment in mass-spectrometry-based identification workflows. We demonstrate the utility of our new probe for proteome-wide target profiling by identifying the cellular targets of (-)-myrocin G, an antiproliferative fungal natural product with a to-date unknown mechanism of action. We show that this natural product and a simplified analogue target the X-ray repair cross-complementing protein 5 (XRCC5), an ATP-dependent DNA helicase that primes DNA repair machinery for nonhomologous end joining (NHEJ) upon DNA double-strand breaks, making them the first reported inhibitors of this biomedically highly important protein. We further demonstrate that myrocins disrupt the interaction of XRCC5 with DNA leading to sensitization of cancer cells to the chemotherapeutic agent etoposide as well as UV-light-induced DNA damage. Altogether, our next-generation cysteine-reactive probe enables broader and deeper profiling of the cysteinome, rendering it a highly attractive tool for elucidation of targets of electrophilic small molecules.


Assuntos
Cisteína/química , Compostos Heterocíclicos com 2 Anéis/química , Hidrocarbonetos Fluorados/química , Sondas Moleculares/química , Proteômica/métodos , Alquilação , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Diterpenos/farmacologia , Inibidores Enzimáticos/farmacologia , Células HEK293 , Células HeLa , Humanos , Autoantígeno Ku/antagonistas & inibidores , Autoantígeno Ku/química
6.
J Am Chem Soc ; 143(11): 4379-4386, 2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33705657

RESUMO

The curcusone natural products are complex diterpenes featuring a characteristic [6-7-5] tricyclic carbon skeleton similar to the daphnane and tigliane diterpenes. Among them, curcusones A-D demonstrated potent anticancer activity against a broad spectrum of human cancer cell lines. Prior to this study, no total synthesis of the curcusones was achieved and their anticancer mode of action remained unknown. Herein, we report our synthetic and chemoproteomics studies of the curcusone diterpenes which culminate in the first total synthesis of several curcusone natural products and identification of BRCA1-associated ATM activator 1 (BRAT1) as a cellular target. Our efficient synthesis is highly convergent, builds upon cheap and abundant starting materials, features a thermal [3,3]-sigmatropic rearrangement and a novel FeCl3-promoted cascade reaction to rapidly construct the critical cycloheptadienone core of the curcusones, and led us to complete the first total synthesis of curcusones A and B in only 9 steps, C and D in 10 steps, and dimericursone A in 12 steps. The chemical synthesis of dimericursone A from curcusones C and D provided direct evidence to support the proposed Diels-Alder dimerization and cheletropic elimination biosynthetic pathway. Using an alkyne-tagged probe molecule, BRAT1, an important but previously "undruggable" oncoprotein, was identified as a key cellular target via chemoproteomics. We further demonstrate for the first time that BRAT1 can be inhibited by curcusone D, resulting in impaired DNA damage response, reduced cancer cell migration, potentiated activity of the DNA damaging drug etoposide, and other phenotypes similar to BRAT1 knockdown.


Assuntos
Produtos Biológicos/química , Diterpenos/química , Proteínas Nucleares/análise , Produtos Biológicos/síntese química , Diterpenos/síntese química , Humanos , Conformação Molecular , Estereoisomerismo
7.
Exp Cell Res ; 389(1): 111890, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32035132

RESUMO

Fibrosis is a key pathological event during muscle aging that accelerates the development of sarcopenia. We show that sarcolipin (SLN) is highly expressed during aging, promotes intracellular calcium overload and participates in impaired myogenic differentiation. d-Galactose (D-gal) was used to induce senescence in C2C12 myoblasts. Conventional AAV-mediated SLN knockdown cells were used to study the role of SLN in muscle physiology and pathophysiology. C2C12 cells were treated with D-gal, which promoted fibrosis and SLN upregulation. The expression of TGF-ß1 and α-SMA, which participate in myogenic transdifferentiation, were also elevated. C2C12 cells with reduced sarcolipin expression produced decreased amounts of collagen. Our study identified an unrecognized role of SLN in regulating myogenic transdifferentiation during aging-associated skeletal muscle cell fibrosis. Targeting SLN may be a novel therapeutic strategy to relieve sarcopenia-associated muscle fibrosis.


Assuntos
Transdiferenciação Celular/efeitos dos fármacos , Proteínas Musculares/farmacologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Proteolipídeos/farmacologia , Sarcopenia/patologia , Animais , Cálcio/metabolismo , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Fibrose , Desenvolvimento Muscular/efeitos dos fármacos , Desenvolvimento Muscular/fisiologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/metabolismo , Sarcopenia/complicações , Sarcopenia/metabolismo
8.
Angew Chem Int Ed Engl ; 60(6): 3071-3079, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33035395

RESUMO

Herein, we report arylazopyrazole ureas and sulfones as a novel class of photoswitchable serine hydrolase inhibitors and present a chemoproteomic platform for rapid discovery of optically controlled serine hydrolase targets in complex proteomes. Specifically, we identify highly potent and selective photoswitchable inhibitors of the drug-metabolizing enzymes carboxylesterases 1 and 2 and demonstrate their pharmacological application by optically controlling the metabolism of the immunosuppressant drug mycophenolate mofetil. Collectively, this proof-of-concept study provides a first example of photopharmacological tools to optically control drug metabolism by modulating the activity of a metabolizing enzyme. Our arylazopyrazole ureas and sulfones offer synthetically accessible scaffolds that can be expanded to identify specific photoswitchable inhibitors for other serine hydrolases, including lipases, peptidases, and proteases. Our chemoproteomic platform can be applied to other photoswitches and scaffolds to achieve optical control over diverse protein classes.


Assuntos
Carboxilesterase/antagonistas & inibidores , Inibidores Enzimáticos/química , Preparações Farmacêuticas/metabolismo , Raios Ultravioleta , Células CACO-2 , Carboxilesterase/metabolismo , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/metabolismo , Humanos , Hidrólise , Microscopia de Fluorescência , Preparações Farmacêuticas/química , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Estereoisomerismo , Sulfonas/química , Sulfonas/metabolismo , Urease/química , Urease/metabolismo
9.
J Bacteriol ; 202(18)2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32540932

RESUMO

LpxC is a deacetylase that catalyzes the first committed step of lipid A biosynthesis in Escherichia coli LpxC competes for a common precursor, R-3-hydroxymyristoyl-UDP-GlcNAc, with FabZ, whose dehydratase activity catalyzes the first committed step of phospholipid biosynthesis. To maintain the optimum flow of the common precursor to these two competing pathways, the LpxC level is controlled by FtsH/YciM-mediated proteolysis. It is not known whether this complex or another protein senses the status of lipid A synthesis to control LpxC proteolysis. The work carried out in this study began with a novel mutation, yejM1163, which causes hypersensitivity to large antibiotics such as vancomycin and erythromycin. Isolates resistant to these antibiotics carried suppressor mutations in the ftsH and yciM genes. Western blot analysis showed a dramatically reduced LpxC level in the yejM1163 background, while the presence of ftsH or yciM suppressor mutations restored LpxC levels to different degrees. Based on these observations, it is proposed that YejM is a sensor of lipid A synthesis and controls LpxC levels by modulating the activity of the FtsH/YciM complex. The truncation of the periplasmic domain in the YejM1163 protein causes unregulated proteolysis of LpxC, thus diverting a greater pool of R-3-hydroxymyristoyl-UDP-GlcNAc toward phospholipid synthesis. This imbalance in lipid synthesis perturbs the outer membrane permeability barrier, causing hypersensitivity toward vancomycin and erythromycin. yejM1163 suppressor mutations in ftsH and yciM lower the proteolytic activity toward LpxC, thus restoring lipid homeostasis and the outer membrane permeability barrier.IMPORTANCE Lipid homeostasis is critical for proper envelope functions. The level of LpxC, which catalyzes the first committed step of lipopolysaccharide (LPS) synthesis, is controlled by an essential protease complex comprised of FtsH and YciM. Work carried out here suggests YejM, an essential envelope protein, plays a central role in sensing the state of LPS synthesis and controls LpxC levels by regulating the activity of FtsH/YciM. All four essential proteins are attractive targets of therapeutic development.


Assuntos
Proteases Dependentes de ATP/metabolismo , Amidoidrolases/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas de Membrana/metabolismo , Farmacorresistência Bacteriana , Regulação Bacteriana da Expressão Gênica , Lipopolissacarídeos/metabolismo
10.
BMC Pulm Med ; 20(1): 49, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087725

RESUMO

BACKGROUND: Sepsis-induced acute lung injury (ALI) is a clinical syndrome characterized by the injury of alveolar epithelium and pulmonary endothelial cells. This study aimed to investigate the regulation of long noncoding RNA (lncRNA) taurine up-regulated gene 1 (TUG1) in a murine ALI model and in primary murine pulmonary microvascular endothelial cells (PMVECs) stimulated with lipopolysaccharide (LPS). METHODS: Adult C57BL/6 mice were intravenously injected with or without TUG1-expressiong adenoviral vector or control vector 1 week before the establishment of ALI model. PMVECs were transfected with TUG1-expressiong or control vectors followed by LPS stimulation. MiR-34b-5p was confirmed as a target of TUG1 using dual-luciferase reporter assay. GRB2 associated binding protein 1 (GAB1) was confirmed as a downstream target of miR-34b-5p using the same method. In the rescue experiment, PMVECs were co-transfected with TUG1-expressing vector and miR-34b-5p mimics (or control mimics) 24 h before LPS treatment. RESULTS: ALI mice showed reduced levels of TUG1, pulmonary injury, and induced apoptosis and inflammation compared to the control group. The overexpression of TUG1 in ALI mice ameliorated sepsis-induced pulmonary injury, apoptosis and inflammation. TUG1 also showed protective effect in LPS-treated PMVECs. The expression of MiR-34b-5p was negatively correlated with the level of TUG1. TUG1-supressed apoptosis and inflammation in LPS-stimulated PMVECs were restored by miR-34b-5p overexpression. GAB1 was inversely regulated by miR-34b-5p but was positively correlated with TUG1 expression. CONCLUSION: TUG1 alleviated sepsis-induced inflammation and apoptosis via targeting miR-34b-5p and GAB1. These findings suggested that TUG1 might be served as a therapeutic potential for the treatment of sepsis-induced ALI.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/etiologia , Proteínas Adaptadoras de Transdução de Sinal/efeitos dos fármacos , RNA Longo não Codificante/farmacologia , RNA Longo não Codificante/uso terapêutico , Sepse/complicações , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/efeitos dos fármacos
11.
J Bacteriol ; 201(17)2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31235517

RESUMO

The intake of certain nutrients, including ferric ion, is facilitated by the outer membrane-localized transporters. Due to ferric insolubility at physiological pH, Escherichia coli secretes a chelator, enterobactin, outside the cell and then transports back the enterobactin-ferric complex via an outer membrane receptor protein, FepA, whose activity is dependent on the proton motive force energy transduced by the TonB-ExbBD complex of the inner membrane. Consequently, ΔtonB mutant cells grow poorly on a medium low in iron. Prolonged incubation of ΔtonB cells on low-iron medium yields faster-growing colonies that acquired suppressor mutations in the yejM (pbgA) gene, which codes for a putative inner-to-outer membrane cardiolipin transporter. Further characterization of suppressors revealed that they display hypersusceptibility to vancomycin, a large hydrophilic antibiotic normally precluded from entering E. coli cells, and leak periplasmic proteins into the culture supernatant, indicating a compromised outer membrane permeability barrier. All phenotypes were reversed by supplying the wild-type copy of yejM on a plasmid, suggesting that yejM mutations are solely responsible for the observed phenotypes. The deletion of all known cardiolipin synthase genes (clsABC) did not produce the phenotypes similar to mutations in the yejM gene, suggesting that the absence of cardiolipin from the outer membrane per se is not responsible for increased outer membrane permeability. Elevated lysophosphatidylethanolamine levels and the synthetic growth phenotype without pldA indicated that defective lipid homeostasis in the yejM mutant compromises outer membrane lipid asymmetry and permeability barrier to allow enterobactin intake, and that YejM has additional roles other than transporting cardiolipin.IMPORTANCE The work presented here describes a positive genetic selection strategy for isolating mutations that destabilize the outer membrane permeability barrier of E. coli Given the importance of the outer membrane in restricting the entry of antibiotics, characterization of the genes and their products that affect outer membrane integrity will enhance the understanding of bacterial membranes and the development of strategies to bypass the outer membrane barrier for improved drug efficacy.


Assuntos
Membrana Externa Bacteriana/fisiologia , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Ferro/metabolismo , Proteínas de Membrana/metabolismo , Antibacterianos/farmacologia , Membrana Externa Bacteriana/química , Transporte Biológico , Cromatografia Líquida , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Ferro/farmacologia , Lipídeos/química , Proteínas de Membrana/genética , Mutação , Permeabilidade , Supressão Genética , Espectrometria de Massas em Tandem
12.
Opt Express ; 27(6): 8819-8837, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31052694

RESUMO

Combining underwater optical imaging principles and the level set, this paper proposes a novel type of level set method called optically guided level set. This novel method can transform optical challenges in underwater environments (such as the illumination bias and wavelength-selective absorption) into valuable guidance for underwater object segmentation. Using the underwater optical guidance, our novel method can generate accurate object segmentation results by suitable initialization and regular evolving of the level set. The optical guidance core lies in two observations pertaining to the underwater optical imaging process: (i) the overlap between the object region and optical collimation region and (ii) the correspondence between the object structure and irradiation distribution inside the optical collimation. The high accuracy of our proposed method is demonstrated via comparisons to the state-of-the-art level set and salient object detection methods for public underwater images collected in diverse environments. Moreover, by using the work presented in this paper, we plan to demonstrate optical principles' potential for improving computer vision research, which is a promising research topic with many practical applications.

13.
Bioorg Med Chem Lett ; 26(18): 4417-4422, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27542306

RESUMO

Five new flavonoids, griffinones A-E (1-5), a new biphenylneolignan, griffilignan A (6) and ten known compounds were isolated from the n-hexane and EtOAc extracts of Millettia griffithii. The structures of the new compounds were determined by 1D and 2D NMR, and by HRMS. The anti-inflammatory activity of the isolated compounds was evaluated on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells. Among the isolated compounds, compounds 1, 2 and 14 showed significant anti-inflammatory activity with IC50 values of 20.4, 2.1 and 35.7µM, respectively and no obvious toxicities were observed at 100µM. Western blot and PCR assay further showed that inhibition of nitric oxide production by compound 2 was associated with suppression of iNOS expression. Modeling studies suggested that the amino group, phenyl ring as well as the isopentenyl tails of compound 2 could help bind to iNOs.


Assuntos
Anti-Inflamatórios/farmacologia , Flavonoides/farmacologia , Lignanas/farmacologia , Millettia/química , Caules de Planta/química , Animais , Linhagem Celular , Lipopolissacarídeos/toxicidade , Espectroscopia de Ressonância Magnética , Camundongos , Espectrometria de Massas por Ionização por Electrospray
14.
Zhongguo Zhong Yao Za Zhi ; 41(1): 124-128, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-28845653

RESUMO

To investigate the metabolic stability and parameters in vitro of lanceolatin B in liver microsomes of rats, human, Beagle dogs, and monkeys, and to identify the phaenotypes of CYP enzymes of lanceolatin B by using the liver microsome incubation system in vitro. After incubated with different species of liver microsomes, lanceolatin B was quantified by UPLC-MS/MS method to evaluate its metabolic stability and metabolic kinetic parameters in vitro. Lanceolatin B was incubated with specific inhibitors of CYP450 isoforms (CYP2E1, 2C19, 1A2, 2D6, 2C9, 3A4, and 2A1) to determine the phaenotypes of metabolic enzymes. The results showed that lanceolatin B was metabolized in the liver microsomes of rats and monkeys but not in the human and Beagle dogs. Their in vitro half-life T1/2 and intrinsic clearance rate CLint in rat and monkey liver microsomes were 11.57,8.07 min, and 0.12,0.17 mL•min⁻¹â€¢mg⁻¹ without significant difference. The results of metabolic phenotyping indicated that CYP1A2 was mainly involved in the metabolism of lanceolatin B. There existed a difference in the metabolism of lanceolatin B in different types of liver microsomes. Several of CYP450 isoforms metabolized lanceolatin B together in liver microsomes of rats, in which CYP1A2 was the major enzyme mainly responsible for the metabolism of lanceolatin B.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Flavonoides/administração & dosagem , Microssomos Hepáticos/enzimologia , Animais , Cromatografia Líquida de Alta Pressão , Sistema Enzimático do Citocromo P-450/química , Cães , Estabilidade Enzimática/efeitos dos fármacos , Flavonoides/química , Haplorrinos , Humanos , Cinética , Masculino , Microssomos Hepáticos/química , Microssomos Hepáticos/efeitos dos fármacos , Ratos , Espectrometria de Massas em Tandem
15.
J Pineal Res ; 58(4): 429-38, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25752481

RESUMO

Melatonin induces apoptosis in many different cancer cell lines, including colorectal cancer. However, the precise mechanisms involved remain largely unresolved. In this study, we provide evidence to reveal a new mechanism by which melatonin induces apoptosis of colorectal cancer LoVo cells. Melatonin at pharmacological concentrations significantly suppressed cell proliferation and induced apoptosis in a dose-dependent manner. The observed apoptosis was accompanied by the melatonin-induced dephosphorylation and nuclear import of histone deacetylase 4 (HDAC4). Pretreatment with a HDAC4-specific siRNA effectively attenuated the melatonin-induced apoptosis, indicating that nuclear localization of HDAC4 is required for melatonin-induced apoptosis. Moreover, constitutively active Ca(2+) /calmodulin-dependent protein kinase II alpha (CaMKIIα) abrogated the melatonin-induced HDAC4 nuclear import and apoptosis of LoVo cells. Furthermore, melatonin decreased H3 acetylation on bcl-2 promoter, leading to a reduction of bcl-2 expression, whereas constitutively active CaMKIIα(T286D) or HDAC4-specific siRNA abrogated the effect of melatonin. In conclusion, the present study provides evidence that melatonin-induced apoptosis in colorectal cancer LoVo cells largely depends on the nuclear import of HDAC4 and subsequent H3 deacetylation via the inactivation of CaMKIIα.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Neoplasias Colorretais/metabolismo , Histona Desacetilases/metabolismo , Melatonina/farmacologia , Proteínas Repressoras/metabolismo , Acetilação/efeitos dos fármacos , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Humanos
16.
Phys Chem Chem Phys ; 16(41): 22659-64, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25231060

RESUMO

Peculiar surface-interface properties of nanocrystalline ceria-cobalt oxides were evidenced by X-ray diffraction, transmission electron microscopy and X-ray absorption spectroscopy. It was found that cobalt foreign cations modify the surface oxygen vacancies of ceria at the atomic level, inducing the exposure of well-defined reactive faces between the ceria-host and the cobalt oxide interface. These modifications of the surface-interface structure promoted a remarkable increase in the oxygen storage capacity of ceria nanocrystals.

17.
Per Med ; 21(4): 219-225, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38904290

RESUMO

Aim: This paper determines the polymorphism distribution of the VDR BsmI gene in 350 patients and provides medication recommendations for osteoporosis based on detection results. Materials & methods: Chi-square tests compared genotype and allele frequencies with other populations. Results: Genotype frequencies were 91.66 bb, 8.72 Bb and 0.21% BB, with allelic frequencies of 95.43 b and 4.57% B, adhering to Hardy-Weinberg equilibrium. These findings suggest that VDR gene polymorphisms, particularly at the BsmIlocus, play an essential role in bone health and osteoporosis treatment. Genotype-based drug selection reduced adverse reactions from 14 to two cases. Conclusion: These findings improve clinical treatment efficacy and guide rational drug use for osteoporosis patients.


[Box: see text].


Assuntos
Frequência do Gene , Osteoporose , Receptores de Calcitriol , Humanos , Osteoporose/genética , Osteoporose/tratamento farmacológico , Receptores de Calcitriol/genética , Feminino , Pessoa de Meia-Idade , Frequência do Gene/genética , Idoso , Masculino , Genótipo , Conservadores da Densidade Óssea/uso terapêutico , Conservadores da Densidade Óssea/farmacologia , Polimorfismo de Nucleotídeo Único/genética , Adulto , Idoso de 80 Anos ou mais , Polimorfismo Genético/genética , Alelos
18.
Int J Biol Macromol ; 271(Pt 1): 132626, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795893

RESUMO

Immobilization of proteolytic enzymes onto nanocarriers is effective to improve drug diffusion in tumors through degrading the dense extracellular matrix (ECM). Herein, immobilization and release behaviors of hyaluronidase, bromelain, and collagenase (Coll) on mesoporous silica nanoparticles (MSNs) were explored. A series of cationic MSNs (CMSNs) with large and adjustable pore sizes were synthesized, and investigated together with two anionic MSNs of different pore sizes. CMSNs4.0 exhibited the highest enzyme loading capacity for hyaluronidase and bromelain, and CMSNs4.5 was the best for Coll. High electrostatic interaction, matched pore size, and large pore volume and surface area favor the immobilization. Changes of the enzyme conformations and surface charges with pH, existence of a space around the immobilized enzymes, and the depth of the pore structures, affect the release ratio and tunability. The optimal CMSNs-enzyme complexes exhibited deep and homogeneous penetration into pancreatic tumors, a tumor model with the densest ECM, with CMSNs4.5-Coll as the best. Upon loading with doxorubicin (DOX), the CMSNs-enzyme complexes induced high anti-tumor efficiencies. Conceivably, the DOX/CMSNs4.5-NH2-Coll nanodrug exhibited the most effective tumor therapy, with a tumor growth inhibition ratio of 86.1 %. The study provides excellent nanocarrier-enzyme complexes, and offers instructive theories for enhanced tumor penetration and therapy.


Assuntos
Doxorrubicina , Enzimas Imobilizadas , Nanopartículas , Dióxido de Silício , Dióxido de Silício/química , Enzimas Imobilizadas/química , Nanopartículas/química , Porosidade , Doxorrubicina/química , Doxorrubicina/farmacologia , Animais , Humanos , Camundongos , Portadores de Fármacos/química , Linhagem Celular Tumoral , Hialuronoglucosaminidase/química , Hialuronoglucosaminidase/metabolismo , Liberação Controlada de Fármacos , Colagenases/metabolismo , Colagenases/química , Bromelaínas/química , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia
19.
Curr Med Sci ; 44(2): 333-345, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622424

RESUMO

OBJECTIVE: Peritoneal fibrosis (PF) is the main cause of declining efficiency and ultrafiltration failure of the peritoneum, which restricts the long-term application of peritoneal dialysis (PD). This study aimed to investigate the therapeutic effects and mechanisms of bone marrow mesenchymal stem cells-derived exosomes (BMSC-Exos) on PF in response to PD. METHODS: Small RNA sequencing analysis of BMSC-Exos was performed by second-generation sequencing. C57BL/6J mice were infused with 4.25% glucose-based peritoneal dialysis fluid (PDF) for 6 consecutive weeks to establish a PF model. A total of 36 mice were randomly divided into 6 groups: control group, 1.5% PDF group, 2.5% PDF group, 4.25% PDF group, BMSC-Exos treatment group, and BMSC-Exos+TP53 treatment group. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed to measure the expression level of miR-27a-3p in BMSC-Exos and peritoneum of mice treated with different concentrations of PDF. HE and Masson staining were performed to evaluate the extent of PF. The therapeutic potential of BMSC-Exos for PF was examined through pathological examination, RT-qPCR, Western blotting, and peritoneal function analyses. Epithelial-mesenchymal transition (EMT) of HMrSV5 was induced with 4.25% PDF. Cells were divided into control group, 4.25% PDF group, BMSC-Exos treatment group, and BMSC-Exos+TP53 treatment group. Cell Counting Kit-8 assay was used to measure cell viability, and transwell migration assay was used to verify the capacity of BMSC-Exos to inhibit EMT in HMrSV5 cells. RESULTS: Small RNA sequencing analysis showed that miR-27a-3p was highly expressed in BMSC-derived exosomes compared to BMSCs. The RT-qPCR results showed that the expression of miR-27a-3p was upregulated in BMSC-Exos, but decreased in PD mice. We found that PF was glucose concentration-dependently enhanced in the peritoneum of the PD mice. Compared with the control mice, the PD mice showed high solute transport and decreased ultrafiltration volume as well as an obvious fibroproliferative response, with markedly increased peritoneal thickness and higher expression of α-SMA, collagen-I, fibronectin, and ECM1. The mice with PD showed decreased miR-27a-3p. Peritoneal structural and functional damage was significantly attenuated after BMSC-Exos treatment, while PF and mesothelial damage were significantly ameliorated. Additionally, markers of fibrosis (α-SMA, collagen-I, fibronectin, ECM1) and profibrotic cytokines (TGF-ß1, PDGF) were downregulated at the mRNA and protein levels after BMSC-Exos treatment. In HMrSV5 cells, BMSC-Exos reversed the decrease in cell viability and the increase in cell migratory capacity caused by high-glucose PDF. Western blotting and RT-qPCR analysis revealed that BMSC-Exos treatment resulted in increased expression of E-cadherin (epithelial marker) and decreased expression of α-SMA, Snail, and vimentin (mesenchymal markers) compared to those of the 4.25% PDF-treated cells. Importantly, a dual-luciferase reporter assay showed that TP53 was a target gene of miR-27a-3p. TP53 overexpression significantly reversed the decreases in PF and EMT progression induced by BMSC-Exos. CONCLUSION: The present results demonstrate that BMSC-Exos showed an obvious protective effect on PD-related PF and suggest that BMSC-derived exosomal miR-27a-3p may exert its inhibitory effect on PF and EMT progression by targeting TP53.


Assuntos
Exossomos , MicroRNAs , Diálise Peritoneal , Fibrose Peritoneal , Camundongos , Animais , Fibrose Peritoneal/genética , Fibrose Peritoneal/terapia , Fibronectinas , Exossomos/metabolismo , Camundongos Endogâmicos C57BL , Diálise Peritoneal/efeitos adversos , MicroRNAs/genética , MicroRNAs/metabolismo , Glucose , Colágeno
20.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(3): 299-304, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-36916344

RESUMO

OBJECTIVE: To establish a modified controlled abciximab and device investigation to lower late angioplasty complication (CADILLAC) score, and to compare the predictive value of modified CADILLAC score, the global registry of acute coronary event (GRACE) score and the thrombolysis in myocardial infarction (TIMI) score in predicting the risk of short-term death after percutaneous coronary intervention (PCI) in patients with acute ST segment elevation myocardial infarction (STEMI). METHODS: A retrospective study was conducted. The clinical data of 169 STEMI patients under going PCI admitted to the department of cardiology of Guizhou Provincial People's Hospital from September 2019 to December 2020 through emergency chest pain fast track were enrolled. A multivariate Logistic regression analysis was used to screen the factors closely related to the mortality risk within 30 days of STEMI, and a modified CADILLAC scoring system was established by referring to CADILLAC scoring settings. The score of modified CADILLAC, GRACE and TIMI scores of patients were calculated after admission, and the number of deaths due to cardiovascular disease (CVD) within 30 days after onset was recorded. The receiver operating characteristic curve (ROC curve) was used to evaluate the predictive value of three scoring systems on the risk of death within 30 days after PCI in patients with STEMI. RESULTS: In 169 STEMI patients, 16 patients died of CVD within 30 days after PCI, and the actual case mortality was 9.47%. Multivariate Logistic regression analysis showed that age > 75 years old, cardiac function Killip ≥ Grade III, ventricular arrhythmia, ST segment elevation ≥ 0.2 mV, cardiac troponin I (cTnI) increase, systolic blood pressure (SBP) < 90 mmHg (1 mmHg ≈ 0.133 kPa) were all independent predictors of death after PCI in STEMI patients. The improved CADILLAC scoring system was constructed based on the above predictive factors combined with left ventricular ejection fraction (LVEF) less than 0.40. The GRACE, TIMI and modified CADILLAC scores of dead patients were significantly higher than those of survival patients (GRACE score: 197.60±31.83 vs. 149.81±36.72, TIMI score: 11.21±2.13 vs. 7.27±1.97, modified CADILLAC score: 12.60±2.52 vs. 6.96±2.17, all P < 0.05). The higher the risk stratification of the three scores, the higher the mortality of patients with CVD within 30 days after PCI [the mortality of patients with low, medium and high risk in GRACE score were 2.41% (2/83), 9.61% (5/52) and 26.47% (9/34); the mortality of patients with low, medium and high risk in TIMI score were 3.12% (3/96), 12.82% (5/39) and 23.53% (8/34); and the mortality of patients with low, medium and high risk in modified CADILLAC score were 3.19% (3/94), 7.69% (4/52) and 39.13% (9/23), respectively, all P < 0.01]. The area under the ROC curve (AUC) of the GRACE, TIMI and the modified CADILLAC scores predicting the risk of death 30 days after PCI in STEMI patients were 0.855 [95% confidence interval (95%CI) was 0.702-0.923], 0.725 (95%CI was 0.666-0.812) and 0.882 (95%CI was 0.732-0.936), respectively, all P = 0.000; the sensitivity of its prediction accuracy were 81.59%, 78.65% and 89.26%, and the specificity were 78.62%, 57.12% and 75.54%, respectively. CONCLUSIONS: The GRACE and the modified CADILLAC scores have predictive value for the short-term mortality risk of STEMI patients after PCI, and the modified CADILLAC score is more accurate. But the TIMI score has a poor predictive effect on the short-term mortality risk of STEMI patients after PCI.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Idoso , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Estudos Retrospectivos , Volume Sistólico , Prognóstico , Medição de Risco , Função Ventricular Esquerda , Infarto do Miocárdio/complicações , Fatores de Risco , Sistema de Registros , Arritmias Cardíacas/complicações
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