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1.
Exp Eye Res ; 244: 109946, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38815794

RESUMO

Photobiomodulation (PBM) therapy uses light of different wavelengths to treat various retinal degeneration diseases, but the potential damage to the retina caused by long-term light irradiation is still unclear. This study were designed to detect the difference between long- and short-wavelength light (650-nm red light and 450-nm blue light, 2.55 mW/cm2, reference intensity in PBM)-induced injury. In addition, a comparative study was conducted to investigate the differences in retinal light damage induced by different irradiation protocols (short periods of repeated irradiation and a long period of constant irradiation). Furthermore, the protective role of PARP-1 inhibition on the molecular mechanism of blue light-induced injury was confirmed by a gene knockdown technique or a specific inhibitor through in vitro and in vivo experiments. The results showed that the susceptibility to retinal damage caused by irradiation with long- and short-wavelength light is different. Shorter wavelength lights, such as blue light, induce more severe retinal damage, while the retina exhibits better resistance to longer wavelength lights, such as red light. In addition, repeated irradiation for short periods induces less retinal damage than constant exposure over a long period. PARP-1 plays a critical role in the molecular mechanism of blue light-induced damage in photoreceptors and retina, and inhibiting PARP-1 can significantly protect the retina against blue light damage. This study lays an experimental foundation for assessing the safety of phototherapy products and for developing target drugs to protect the retina from light damage.


Assuntos
Luz , Poli(ADP-Ribose) Polimerase-1 , Retina , Degeneração Retiniana , Animais , Poli(ADP-Ribose) Polimerase-1/metabolismo , Camundongos , Luz/efeitos adversos , Retina/efeitos da radiação , Retina/patologia , Degeneração Retiniana/etiologia , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Degeneração Retiniana/prevenção & controle , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/patologia , Lesões Experimentais por Radiação/metabolismo , Modelos Animais de Doenças , Western Blotting , Masculino , Terapia com Luz de Baixa Intensidade , Luz Azul
2.
Cell Mol Neurobiol ; 43(3): 1037-1048, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35792991

RESUMO

Retinitis pigmentosa (RP) is a group of genetic disorders resulting in inherited blindness due to the degeneration of rod and cone photoreceptors. The various mechanisms underlying rod degeneration primarily rely on genetic mutations, leading to night blindness initially. Cones gradually degenerate after rods are almost eliminated, resulting in varying degrees of visual disability and blindness. The mechanism of cone degeneration remains unclear. An understanding of the mechanisms underlying cone degeneration in RP, a highly heterogeneous disease, is essential to develop novel treatments of RP. Herein, we review recent advancements in the five hypotheses of cone degeneration, including oxidative stress, trophic factors, metabolic stress, light damage, and inflammation activation. We also discuss the connection among these theories to provide a better understanding of secondary cone degeneration in RP. Five current mechanisms of cone degenerations in RP Interactions among different pathways are involved in RP.


Assuntos
Células Fotorreceptoras Retinianas Cones , Retinose Pigmentar , Humanos , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo , Retinose Pigmentar/terapia , Cegueira/metabolismo , Estresse Oxidativo
3.
Cell Mol Neurobiol ; 43(7): 3265-3276, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37391574

RESUMO

The retinal pigment epithelium (RPE) is a highly specialized and polarized epithelial cell layer that plays an important role in sustaining the structural and functional integrity of photoreceptors. However, the death of RPE is a common pathological feature in various retinal diseases, especially in age-related macular degeneration (AMD) and diabetic retinopathy (DR). Mitophagy, as a programmed self-degradation of dysfunctional mitochondria, is crucial for maintaining cellular homeostasis and cell survival under stress. RPE contains a high density of mitochondria necessary for it to meet energy demands, so severe stimuli can cause mitochondrial dysfunction and the excess generation of intracellular reactive oxygen species (ROS), which can further trigger oxidative stress-involved mitophagy. In this review, we summarize the classical pathways of oxidative stress-involved mitophagy in RPE and investigate its role in the progression of retinal diseases, aiming to provide a new therapeutic strategy for treating retinal degenerative diseases. The role of mitophagy in AMD and DR. In AMD, excessive ROS production promotes mitophagy in the RPE by activating the Nrf2/p62 pathway, while in DR, ROS may suppress mitophagy by the FOXO3-PINK1/parkin signaling pathway or the TXNIP-mitochondria-lysosome-mediated mitophagy.


Assuntos
Degeneração Macular , Epitélio Pigmentado da Retina , Humanos , Epitélio Pigmentado da Retina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Mitofagia , Estresse Oxidativo/fisiologia
4.
Int Ophthalmol ; 43(7): 2575-2588, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36715956

RESUMO

PURPOSE: Due to the inimitable anatomical structure of the eyeball and various physiological barriers, conventional ocular local administration is often complicated by apparent shortcomings, such as limited bioavailability and short drug retention. Thus, developing methods for sustainable, safe and efficient drug delivery to ocular target sites has long been an urgent need. This study briefly summarizes the barriers to ocular drug administration and various ocular drug delivery routes and highlights recent progress in ocular implantable sustained-release drug delivery systems (DDSs) to provide literature evidence for developing novel ocular implants for sustained drug delivery. METHODS: We conducted a comprehensive search of studies on ocular implantable sustained-release DDSs in PubMed and Web of Science using the following keywords: ocular, implantable and drug delivery system. More than 400 papers were extracted. Publications focused on sustained and controlled drug release were primarily considered. Experimental articles involving DDSs that cannot be implanted into the eye through surgeries and cannot be inserted into ocular tissues in solid form were excluded. Approximately 143 publications were reviewed to summarize the most current information on the subject. RESULTS: In recent years, numerous ocular sustained-release DDSs using lipids, nanoparticles and hydrogels as carriers have emerged. With unique properties and systematic design, ocular implantable sustained-release DDSs are able to continuously maintain drug release, effectively sustain the therapeutic concentration in target tissues, and substantially enhance the therapeutic efficacy. Nevertheless, few ocular implantable sustained-release DDSs have been available in clinical use. CONCLUSIONS: Ocular implantable sustained-release DDSs have become a new focus in the field of ocular drug development through unique designs and improvements in the materials of drug carriers, administration methods and dosage forms. With more ocular implantable sustained-release DDSs being commercialized, ocular therapeutics may be revolutionized.


Assuntos
Sistemas de Liberação de Medicamentos , Olho , Humanos , Preparações de Ação Retardada/farmacologia , Preparações de Ação Retardada/uso terapêutico , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Administração Oftálmica
5.
Antonie Van Leeuwenhoek ; 114(11): 1805-1818, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34426860

RESUMO

Two Gram-stain negative, facultative anaerobic, oxidase-negative, catalase-positive bacilli, designated as strains TMQ4T and TMQ2, were isolated from Xiaoshi Island, China, using prey-traps. Growth was observed within the ranges 25-45 °C (optimally at 37 °C), pH 6.5-9.0 (optimally at pH 7.5-8.0) and 1-8% NaCl (optimally at 3-4%, w/v). The draft genome sequences of strains TMQ4T and TMQ2 contained 184 contigs of 5,609,735 bp with a G+C content of 64.4% and 148 contigs of 5,589,985 bp with a G+C content of 65.0%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences showed that both strains belonged to the genus Lujinxingia with the similarity of 98.9%. The phylogenetic and phylogenomic topologies and analyses demonstrated that both strains clustered together and differentiated from the closest neighbour, Lujinxingia sediminis SEH01T. Genomic analyses showed that two strains lost the biosynthesis pathway of several chemical compounds. Iso-C15:0 was contained in the predominant cellular fatty acids in both strains. The major polar lipids of both strains consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and unidentified lipids; and the respiratory quinone was menaquinone MK-7 for both strains. Both strains predated other bacteria, including Owenweeksia hongkongensis JCM 12287T and Paraliobacillus ryukyuensis DSM 15140T, and were lured with one prey Acinetobacter baumannii ATCC 19606T in prey-trap. Combining genomic analyses, two strains had the predatory indices of 2, similar to representative typical bacterial predators. The physiological, biochemical, and phylogenetic properties suggest that the two strains represent a novel species within the genus Lujinxingia. The name Lujinxingia vulgaris sp. nov. is proposed, with strain TMQ4T (= KCTC 62851T = MCCC 1H00392T) as type strain and strain TMQ2 (= KCTC 72,079 = MCCC 1H00381) as reference strain.


Assuntos
Sedimentos Geológicos , Água do Mar , Bacillaceae , Técnicas de Tipagem Bacteriana , Bacteroidetes , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Antonie Van Leeuwenhoek ; 114(6): 765-775, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33751321

RESUMO

A facultatively anaerobic bacterium, strain W62T, was isolated from the marine solar saltern in Weihai, China. Cells of the novel strain were Gram-stain negative, non-flagellated, non-gliding, rod-shaped and around 0.3-0.5 × 2.5-3.9 µm in size. Optimum growth occurred at 33-37 °C, with 3-5% (w/v) NaCl and at pH 7.0-7.5. On the basis of phylogenetic analysis of the 16S rRNA gene sequence, strain W62T had close relationship with Marinobacter vulgaris F01T (98.6%), Marinobacter confluentis KCTC 42705T (98.4%) and Marinobacter halotolerans NBRC 110910T (97.7%). Genome sequencing revealed a genome size of 4,050,555 bp, a G+C content of 57.3% and a complete sox system related to thiosulfate oxidization. Strain W62T had ubiquinone-9 as the sole respiratory quinone and possessed Summed Features 3 (C16:1 ω7c/C16:1 ω6c), C16:0 and C18:1 ω9c as the major fatty acids. The major polar lipids of strain W62T were identified as aminophospholipid, phosphatidylglycerol and phosphatidylethanolamine. According to the results of the phenotypic, chemotaxonomic characterization, phylogenetic properties and genome analysis, strain W62T should represent a novel specie of the genus Marinobacter, for which the name Marinobacter orientalis sp. nov. is proposed. The type strain is W62T (= MCCC 1H00317T = KCTC 62593T).


Assuntos
Marinobacter , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Marinobacter/genética , Oxirredução , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Água do Mar , Análise de Sequência de DNA , Tiossulfatos
7.
Cell Commun Signal ; 18(1): 27, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066462

RESUMO

BACKGROUND: Excessive light exposure is a detrimental environmental factor that plays a critical role in the pathogenesis of retinal degeneration. However, the mechanism of light-induced death of retina/photoreceptor cells remains unclear. The mammalian/mechanistic target of rapamycin (mTOR) and Poly (ADP-ribose) polymerase-1 (PARP-1) have become the primary targets for treating many neurodegenerative disorders. The aim of this study was to elucidate the mechanisms underlying light-induced photoreceptor cell death and whether the neuroprotective effects of mTOR and PARP-1 inhibition against death are mediated through apoptosis-inducing factor (AIF). METHODS: Propidium iodide (PI)/Hoechst staining, lentiviral-mediated short hairpin RNA (shRNA), Western blot analysis, cellular fraction separation, plasmid transient transfection, laser confocal microscopy, a mice model, electroretinography (ERG), and hematoxylin-eosin (H & E) staining were employed to explore the mechanisms by which rapamycin/3-Aminobenzamide (3AB) exert neuroprotective effects of mTOR/PARP-1 inhibition in light-injured retinas. RESULTS: A parthanatos-like death mechanism was evaluated in light-injured 661 W cells that are an immortalized photoreceptor-like cell line that exhibit cellular and biochemical feature characteristics of cone photoreceptor cells. The death process featured over-activation of PARP-1 and AIF nuclear translocation. Either PARP-1 or AIF knockdown played a significantly protective role for light-damaged photoreceptors. More importantly, crosstalk was observed between mTOR and PARP-1 signaling and mTOR could have regulated parthanatos via the intermediate factor sirtuin 1 (SIRT1). The parthanatos-like injury was also verified in vivo, wherein either PARP-1 or mTOR inhibition provided significant neuroprotection against light-induced injury, which is evinced by both structural and functional retinal analysis. Overall, these results elucidate the mTOR-regulated parthanatos death mechanism in light-injured photoreceptors/retinas and may facilitate the development of novel neuroprotective therapies for retinal degeneration diseases. CONCLUSIONS: Our results demonstrate that inhibition of the mTOR/PARP-1 axis exerts protective effects on photoreceptors against visible-light-induced parthanatos. These protective effects are conducted by regulating the downstream factors of AIF, while mTOR possibly interacts with PARP-1 via SIRT1 to regulate parthanatos. Video Abstract Schematic diagram of mTOR interacting with PARP-1 to regulate visible light-induced parthanatos. Increased ROS caused by light exposure penetrates the nuclear membrane and causes nuclear DNA strand breaks. PARP-1 detects DNA breaks and synthesizes PAR polymers to initiate the DNA repair system that consumes a large amount of cellular NAD+. Over-production of PAR polymers prompts the release of AIF from the mitochondria and translocation to the nucleus, which leads to parthanatos. Activated mTOR may interact with PARP-1 via SIRT1 to regulate visible light-induced parthanatos.


Assuntos
Luz/efeitos adversos , Parthanatos , Células Fotorreceptoras de Vertebrados , Poli(ADP-Ribose) Polimerase-1/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Animais , Fator de Indução de Apoptose/metabolismo , Linhagem Celular , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia
8.
Int J Syst Evol Microbiol ; 70(3): 1617-1622, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32228747

RESUMO

A taxonomic study was carried out on strain SH27T, which was isolated from seawater collected around Xiaoshi Island, PR China. Cells of strain SH27T were Gram-stain-negative, non-motile, rod-shaped, orange-pigmented and grew at 15-37 °C (optimum, 28 °C), at pH 6.0-8.0 (pH 7.0) and in 1.0-7.0 % (w/v) NaCl (2.0-3.0 %). The isolate was positive for catalase, but negative for nitrate reduction, oxidase, indole production and urease. Carotenoid pigment was produced. Phylogenetic analysis based on the 16S rRNA gene placed strain SH27T in the genus Dokdonia with the closest relative being Dokdonia donghaensis KCTC 12391T, exhibiting 96.7 % 16S rRNA gene pairwise similarity. The results of genomic comparisons, including average nucleotide identity and digital DNA-DNA hybridization, showed 72.9 and 19.2 % identity to D. donghaensis KCTC 12391T, respectively. The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine and two unidentified lipids. Menaquinone-6 was the only respiratory quinone. The G+C content of the genomic DNA was 32.9 mol%. On the basis of the phenotypic and phylogenetic data, strain SH27T represents a novel species of the genus Dokdonia, for which the name Dokdonia sinensis sp. nov. is proposed, with the type strain SH27T (MCCC 1H00358T=CCTCC AB 2018323T=KCTC 62962T).


Assuntos
Flavobacterium/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/classificação , Flavobacterium/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química , Microbiologia da Água
9.
Int Ophthalmol ; 40(4): 1017-1027, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31802371

RESUMO

PURPOSE: To analyze the protective effect of PARP inhibitors on light-damaged retina and explore its possible mechanism from the perspective of ciliopathy. METHODS: A systematic review of the literature was performed to investigate the protection of PARP inhibition on light-damaged cilia. PubMed database was retrieved to find the relevant studies and 119 literatures were involved in the review. RESULTS: In retina, the outer segment of photoreceptor is regarded as a special type of primary cilium, so various retinal diseases actually belong to a type of ciliopathy. The retina is the only central nervous tissue exposed to light, but poly (ADP-ribose) polymerase (PARP), as a nuclear enzyme repairing DNA breaks, is overactivated during the light-induced DNA damage, and is involved in the cell death cascade. Studies show that both ATR and phosphorylated Akt colocalize with cilium and play an important role in regulating ciliary function. PARP may function at ATR or PI3K/Akt signal to exert protective effect on cilia. CONCLUSION: PARP inhibitors may protect the cilia/OS of photoreceptor during light-induced damage, which the possible mechanism may be involved in the activation of ATR and PI3K/Akt signal.


Assuntos
Cílios/efeitos dos fármacos , Queimaduras Oculares/prevenção & controle , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Acuidade Visual/efeitos dos fármacos , Animais , Cílios/efeitos da radiação , Queimaduras Oculares/diagnóstico por imagem , Queimaduras Oculares/fisiopatologia , Humanos , Luz/efeitos adversos , Acuidade Visual/efeitos da radiação
10.
Chemistry ; 25(4): 966-970, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30324715

RESUMO

A copper-catalyzed trifunctionalization of alkynes that provides rapid access to oxindoles bearing a geminal diboronate side chain, highlighted by the simultaneous formation of one C-C bond and two C-B bonds, is reported. This new reaction features simple reaction conditions (ligand-free catalysis), a general substrate scope, and excellent chemoselectivity. Mechanistic study revealed a reaction sequence constituted by, in the order, borylation, intramolecular cross-coupling, hydroboration, which has been rarely documented.

11.
Chemistry ; 24(13): 3192-3198, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29210125

RESUMO

A new luminescent ZnII -MOF with 1D triangular channels along the b axis, namely NUM-5, has been successfully assembled and well characterized, which features good stability, especially in aqueous solution. Interestingly, this compound exhibits a fast, sensitive and selective luminescence quenching response towards CrVI (Cr2 O72- /CrO42- ) in aqueous solution. The detection limits towards Cr2 O72- and CrO42- ions are estimated to be 0.7 and 0.3 ppm, respectively, which are among the lowest detection limits reported for the MOF-based fluorescent probes that can simultaneously detect Cr2 O72- and CrO42- in aqueous environment. The possible detection mechanism has been discussed in detail. Moreover, it can be easily regenerated after detection experiments, indicative of excellent recyclability. All these results suggest NUM-5 to be a highly selective and recyclable luminescent sensing material for the quantitative detection of CrVI anions in aqueous solution.

13.
Mar Drugs ; 16(2)2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29414856

RESUMO

Xanthomonas oryzae pv. oryzae, which causes rice bacterial blight, is one of the most destructive pathogenic bacteria. Biological control against plant pathogens has recently received increasing interest. 1-Deoxy-N-acetylglucosamine (1-DGlcNAc) was extracted from the supernatant of Virgibacillus dokdonensis MCCC 1A00493 fermentation through antibacterial bioassay-guided isolation. Its structure was elucidated by LC/MS, NMR, chemical synthesis and time-dependent density functional theory (TD-DFT) calculations. 1-DGlcNAc specifically suppressed X. oryzae pv. oryzae PXO99A (MIC was 23.90 µg/mL), but not other common pathogens including Xanthomonas campestris pv. campestris str.8004 and Xanthomonas oryzae pv. oryzicola RS105. However, its diastereomer (2-acetamido-1,5-anhydro-2-deoxy-d-mannitol) also has no activity to X. oryzae pv. oryzae. This result suggested that activity of 1-DGlcNAc was related to the difference in the spatial conformation of the 2-acetamido moiety, which might be attributed to their different interactions with a receptor. Eighty-four unique proteins were found in X. oryzae pv. oryzae PXO99A compared with the genome of strains8004 and RS105 by blastp. There may be unique interactions between 1-DGlcNAc and one or more of these unique proteins in X. oryzae pv. oryzae. Quantitative real-time PCR and the pharmMapper server indicated that proteins involved in cell division could be the targets in PXO99A. This research suggested that specificity of active substance was based on the active group and spatial conformation selection, and these unique proteins could help to reveal the specific mechanism of action of 1-DGlcNAc against PXO99A.


Assuntos
Acetilglucosamina/análogos & derivados , Antibacterianos/química , Antibacterianos/farmacologia , Virgibacillus/química , Acetilglucosamina/química , Acetilglucosamina/farmacologia , Fermentação , Regulação Bacteriana da Expressão Gênica , Testes de Sensibilidade Microbiana , Oryza/microbiologia , Doenças das Plantas/microbiologia , Água do Mar/microbiologia , Estereoisomerismo , Relação Estrutura-Atividade , Virgibacillus/genética , Xanthomonas/efeitos dos fármacos , Xanthomonas/genética
14.
Graefes Arch Clin Exp Ophthalmol ; 255(10): 2051-2057, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28786025

RESUMO

PURPOSE: One of the key challenges during orbital fracture reconstructive surgery, due to the complex anatomy of the orbit, is shaping and trimming the precise contour of the implants. The objectives of this study were to describe and evaluate the use of a three-dimensional (3-D) printing technique for personalized reconstructive surgery for repairing orbital fractures. METHODS: A total of 29 cases which had 3-D technique-assisted surgical reconstruction, and 27 cases which had traditional surgery, were retrospectively analyzed. Preoperative and postoperative CT images were measured using MIMICS software, and the contour of the fracture zone and the Medpor-titanium implant were analyzed and compared. The surgical duration was also compared between the two groups. RESULTS: There were statistically significant differences in the maximum width, depth and area between fracture zone and implant between the two groups, with the absolute value in the 3-D group markedly lower as compared to the control group. In addition, the difference in the medial-inferior wall angle between the surgical eye and healthy eye was also statistically significant between the groups. The average surgical duration in the 3-D group was substantially shorter than in the control group. Additionally, the postoperative clinical evaluation in the 3-D group was superior to that of the control group. CONCLUSION: The 3-D printing technique is of great value for predicting the precise fracture zone before, and during, personalized surgery, and can help surgeons achieve accurate anatomical reconstruction for repairs of blowout orbital fractures. Moreover, the simulated bone template produced by 3-D printing models allows for "true-to-original" orbital reconstruction, which can shorten the surgical duration and improve the accuracy and safety of the operation.


Assuntos
Simulação por Computador , Procedimentos Cirúrgicos Oftalmológicos/métodos , Órbita/diagnóstico por imagem , Fraturas Orbitárias/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Impressão Tridimensional , Próteses e Implantes , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Órbita/cirurgia , Fraturas Orbitárias/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
15.
Chem Biodivers ; 14(5)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28130826

RESUMO

One new ent-kaurane diterpenoid, 11ß,16α-dihydroxy-ent-kauran-19-oic acid (1), together with eight known analogues 2 - 9 were isolated from the aerial parts of Wedelia prostrata. One of the acidic diterpenoids, kaurenoic acid (3), was converted to seven derivatives, 10 - 16. All compounds were evaluated for their cytotoxic activity in vitro against human leukemia (K562), liver (HepG-2), and stomach (SGC-7901) cancer cell lines. Only four kaurenoic acid derivatives, 13 - 16, with 15-keto and substitutions at C(19) position, exhibited notable cytotoxic activities on these tumor cell lines with IC50 value ranging from 0.05 to 3.71 µm. Compounds 10 - 12, with oxime on C(15) showed moderate inhibitory effects and compounds 1 - 9 showed no cytotoxicities on them. Structure-activity relationships were also discussed based on the experimental data obtained. The known derivative, 15-oxokaurenoic acid 4-piperdin-1-ylbutyl ester (17), induced typical apoptotic cell death in colon SW480 cells upon evaluation of the apoptosis-inducing activity by flow-cytometric analysis.


Assuntos
Diterpenos/isolamento & purificação , Diterpenos/toxicidade , Wedelia/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Diterpenos do Tipo Caurano/isolamento & purificação , Células Hep G2 , Humanos , Concentração Inibidora 50 , Células K562 , Componentes Aéreos da Planta/química , Relação Estrutura-Atividade
16.
Int J Mol Sci ; 18(1)2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-28106827

RESUMO

The retina is a specialized sensory organ, which is essential for light detection and visual formation in the human eye. Inherited retinal degenerations are a heterogeneous group of eye diseases that can eventually cause permanent vision loss. UPR (unfolded protein response) and ER (endoplasmic reticulum) stress plays an important role in the pathological mechanism of retinal degenerative diseases. mTOR (the mammalian target of rapamycin) kinase, as a signaling hub, controls many cellular processes, covering protein synthesis, RNA translation, ER stress, and apoptosis. Here, the hypothesis that inhibition of mTOR signaling suppresses ER stress-induced cell death in retinal degenerative disorders is discussed. This review surveys knowledge of the influence of mTOR signaling on ER stress arising from misfolded proteins and genetic mutations in retinal degenerative diseases and highlights potential neuroprotective strategies for treatment and therapeutic implications.


Assuntos
Estresse do Retículo Endoplasmático , Fármacos Neuroprotetores/uso terapêutico , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/patologia , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos
17.
Int J Syst Evol Microbiol ; 66(11): 4506-4511, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27503117

RESUMO

Strain Ery9T, isolated from surface seawater of the Atlantic Ocean, and strain Ery22T, isolated from deep-sea sediment of the Indian Ocean, were subjected to a taxonomic study using a polyphasic approach. Cells of the two strains were Gram-stain-negative, aerobic and rod-shaped. They produced yellow pigments and lacked bacteriochlorophyll a. On the basis of 16S rRNA gene sequence analysis, strain Ery9T was closely related to Croceicoccus naphthovorans PQ-2T (with 16S rRNA gene sequence similarity of 97.7 %), and strain Ery22T was closely related to Croceicoccusmarinus E4A9T (98.3 %). The 16S rRNA gene sequence similarity between strain Ery9T and strain Ery22T was 96.6 %. Phylogenetic analyses revealed that strains Ery9T and Ery22T fell within the cluster of the genus Croceicoccus and represented two independent lineages. The average nucleotide identity (ANI) values and the genome-to-genome distances between strains Ery9T and Ery22T and the type strains of species of the genus Croceicoccus with validly published names were 73.7-78.4 % and 20.1-22.3 %, respectively. The major respiratory quinone of the two isolates was ubiquinone-10 (Q-10). The DNA G+C contents of strains Ery9T and Ery22T were 62.8 and 62.5 mol%, respectively. Differential phylogenetic distinctiveness and chemotaxonomic differences, together with phenotypic properties, revealed that strains Ery9T and Ery22T could be differentiated from their closely related species. Therefore, it is concluded that strains Ery9T and Ery22T represent two novel species of the genus Croceicoccus, for which the names Croceicoccus pelagius sp. nov. (type strain Ery9T=CGMCC 1.15358T=DSM 101479T) and Croceicoccus mobilis sp. nov. (type strain Ery22T=CGMCC 1.15360T=DSM 101481T), are proposed.


Assuntos
Alphaproteobacteria/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/genética , Alphaproteobacteria/isolamento & purificação , Oceano Atlântico , Técnicas de Tipagem Bacteriana , Bacterioclorofila A/química , Composição de Bases , DNA Bacteriano/genética , Oceano Índico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
18.
Zhonghua Nan Ke Xue ; 22(6): 496-500, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28963836

RESUMO

OBJECTIVE: To determine the zinc levels in the expressed prostatic secretion (EPS) of the patients with different types of chronic nonbacterial prostatitis, and explore the reference value of zinc concentration in EPS in the diagnosis and treatment of prostatitis. METHODS: We collected EPS samples from 35 healthy men and 173 patients with chronic nonbacterial prostatitis, including 65 cases of type ⅢA, 69 cases of type ⅢB, and 39 cases of type Ⅳ, according to the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI). We compared the zinc levels in the EPS samples among different groups and analyzed the correlations of zinc concentration with the NIH-CPSI scores, WBC count, pH value, and age of the subjects. RESULTS: The participants were aged 17-65 (32.5±8.5) years. The zinc concentrations in the EPS were significantly lower in the ⅢA (ï¼»162.2±10.8ï¼½ µg/ml) and ⅢB (ï¼»171.2±12.0ï¼½ µg/ml) than in the Ⅳ (ï¼»234.6±17.9ï¼½ µg/ml) (P<0.05 ) and the control group (ï¼»259.5±14.6ï¼½ µg/ml) (P<0.05 ). The zinc level was correlated negatively with the NIH-CPSI pain score (r=-0.248, P<0.01), quality of life score (r=-0.232, P<0.01), severity score (r=-0.270, P<0.01), total NIH-CPSI score (r=-0.281, P<0.01), and the pH value in EPS (r=-0.208, P<0.01), but showed no correlation with the WBC count and age of the subjects. CONCLUSIONS: The reduced zinc concentration in the EPS of the patients with chronic nonbacterial prostatitis may be associated with the pain symptoms of the disease, which suggests the potential reference value of measuring the zinc concentration in EPS in the diagnosis and treatment of prostatitis.


Assuntos
Dor/metabolismo , Prostatite/fisiopatologia , Zinco/metabolismo , Adolescente , Adulto , Idoso , Doença Crônica , Humanos , Masculino , Pessoa de Meia-Idade , Prostatite/metabolismo , Qualidade de Vida , Adulto Jovem
19.
Biochem Biophys Res Commun ; 450(2): 966-72, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-24971547

RESUMO

Autophagy, a conserved cellular self-degradation process, not only serves to protect cells at critical times during development and nutrient stress, but also contributes to cell death. Photoreceptor cells are unique neurons which when directly exposed to the light, transduces light stimuli into visual signal. However, intense light exposure can be cytotoxic to the retina. So far, the precise mechanism underlying retina light injury remains unknown, and the effective therapy is still unavailable. Here, we found that visible light exposure activated the mitogen-activated protein kinases (MAPK) pathway and led to remarkable autophagy in photoreceptor cells (661W cells). Directly blocking autophagy with 3MA or LY294002 markedly attenuated light-induced death in 661W cells. Among the activated downstream factors of MAPK pathway, ERK, not JNK or p-38, played a critical role in light-induced death mechanism. Inhibiting the activation of ERK with its specific inhibitor PD98059 significantly suppressed light-induced autophagy and protected 661W cells from light injury. These results indicate that autophagy is an essential event in light-induced photoreceptor death and that directly blocking autophagy or suppressing autophagy by inhibiting the ERK pathway could effectively attenuates light-induced damage. These observations may have a potential application in the treatment of retinal light injury.


Assuntos
Autofagia/efeitos da radiação , Luz/efeitos adversos , Células Fotorreceptoras de Vertebrados/efeitos da radiação , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular , Cromonas/farmacologia , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Células Fotorreceptoras de Vertebrados/citologia , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos
20.
Neurol Sci ; 35(5): 687-93, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24277204

RESUMO

The purpose of this study was to determine whether the antibiotic erythromycin induces tolerance against focal cerebral ischemia, and the possible underlying mechanism including the involvement of neuronal nitric oxide synthase (nNOS) and hypoxia-inducible factor-1α (HIF-1α). In rat focal cerebral ischemia models, we found that erythromycin preconditioning could significantly decrease the cerebral infarct volume and brain edema. Meanwhile, the neurological deficits from day 4 through 7 after surgery were also remarkably decreased after erythromycin preconditioning. Moreover, erythromycin preconditioning induced significantly increased nNOS levels and decreased HIF-1α levels in both mRNA and protein expression. This study for the first time indicated that erythromycin preconditioning could induce focal brain ischemic tolerance and attenuate brain injury of subsequent transient focal cerebral ischemia. The potential mechanism may be due to up-regulation of nNOS, but the HIF-1α system was not involved.


Assuntos
Eritromicina/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/fisiopatologia , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase Tipo I/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Edema Encefálico/patologia , Edema Encefálico/fisiopatologia , Edema Encefálico/prevenção & controle , Isquemia Encefálica , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Infarto da Artéria Cerebral Média/patologia , Masculino , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos Wistar , Índice de Gravidade de Doença , Regulação para Cima/efeitos dos fármacos
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