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1.
BMC Infect Dis ; 24(1): 738, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39061029

RESUMO

BACKGROUND: The objective of this study was to explore the correlation between statin administration in the intensive care unit (ICU) setting and the in-hospital mortality risk of patients suffering from sepsis-induced coagulopathy (SIC). METHODS: Utilizing a retrospective cohort study design, this investigation collected data from the Medical Information Mart for Intensive Care (MIMIC)-IV spanning 2008 to 2019. The diagnosis of SIC was established based on a SIC score of 4 or above. Statin usage during the ICU period was extracted from the prescription records based on the keywords of statin medications. The primary endpoint analyzed was the in-hospital mortality within the ICU, characterized by any death occurring during the ICU admission. RESULTS: During the follow-up, which had a median duration of approximately 7.28 days, 18.19% of the 4,777 SIC patients died in the ICU. Statin was linked with a decrease in the risk of in-hospital mortality for SIC patients in the ICU [hazard ratio (HR): 0.73, 95% confidence interval (CI): 0.60-0.89, P = 0.002]. Relative to rosuvastatin, the use of atorvastatin (HR: 0.54, 95% CI: 0.34-0.85, P = 0.008) or simvastatin (HR: 0.55, 95% CI: 0.33-0.92, P = 0.024), as well as combinations of multiple statins (HR: 0.36, 95% CI: 0.15-0.86, P = 0.022), was associated with a reduction in ICU in-hospital mortality risk. Subgroup analysis also suggested that the use of atorvastatin, simvastatin, or a combination of statins had an advantage over rosuvastatin in reducing ICU in-hospital mortality in SIC patients older than 65 years of age or SIC patients with respiratory failure or cardiogenic shock (all P < 0.05). CONCLUSION: The present study supports the potential benefits of statin use in mortality in SIC patients during ICU stays. The study encourages clinicians to consider the benefits of statins and supports the ongoing exploration of statins for enhanced outcomes in critical care settings.


Assuntos
Mortalidade Hospitalar , Inibidores de Hidroximetilglutaril-CoA Redutases , Unidades de Terapia Intensiva , Sepse , Humanos , Masculino , Sepse/mortalidade , Sepse/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Feminino , Unidades de Terapia Intensiva/estatística & dados numéricos , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Transtornos da Coagulação Sanguínea/mortalidade , Transtornos da Coagulação Sanguínea/etiologia , Bases de Dados Factuais , Idoso de 80 Anos ou mais
2.
Exp Eye Res ; 215: 108906, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34953864

RESUMO

Müller cells maintain homeostatic functions in the retina. Their dysfunction leads to irreversible retinal diseases. Oxidative injury is a leading cause of retinal cytotoxicity. Our previous studies reported several betulinic acid (BA) derivatives can protect Müller cells from oxidative injury but achieving pharmacologically effective concentrations in the Müller cells could be a limitation. To optimise cellular delivery, we encapsulated the BA analogues H3, H5 and H7 into the clinically approved Compritol 888 and HD5 ATO solid lipid nanoparticles (SLNs) using the micro-emulsion method. The cytoprotective effects of these SLN-formulations were determined in human MIO-M1 cells. We found cytoprotection by H3 and H5 SLN-formulations was significantly enhanced, which was evident at concentrations much lower than those required with the free agents. Both SLN-formulations prolonged the duration of action of these agents. The most effective agent H5 delivered in 888 ATO SLNs attenuated glutamate-induced ROS formation and the associated necrosis in MIO-M1 cells. Overall, SLNs have emerged as promising delivery carriers for BA derivatives enhancing their protective effects against oxidative injury in human Müller cells. Our study is the first to show SLNs can be a viable route to delivery agents with improved efficacy and stability into human Müller cells favoring the treatment/prevention of retinal diseases.


Assuntos
Nanopartículas , Doenças Retinianas , Portadores de Fármacos , Células Ependimogliais , Humanos , Lipossomos , Estresse Oxidativo , Triterpenos Pentacíclicos , Ácido Betulínico
3.
Antimicrob Agents Chemother ; 65(9): e0083521, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34228550

RESUMO

Inhaled polymyxins are associated with toxicity in human lung epithelial cells that involves multiple apoptotic pathways. However, the mechanism of polymyxin-induced pulmonary toxicity remains unclear. This study aims to investigate polymyxin-induced metabolomic perturbations in human lung epithelial A549 cells. A549 cells were treated with 0.5 or 1.0 mM polymyxin B or colistin for 1, 4, and 24 h. Cellular metabolites were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), and significantly perturbed metabolites (log2 fold change [log2FC] ≥ 1; false-discovery rate [FDR] ≤ 0.2) and key pathways were identified relative to untreated control samples. At 1 and 4 h, very few significant changes in metabolites were observed relative to the untreated control cells. At 24 h, taurine (log2FC = -1.34 ± 0.64) and hypotaurine (log2FC = -1.20 ± 0.27) were significantly decreased by 1.0 mM polymyxin B. The reduced form of glutathione (GSH) was significantly depleted by 1.0 mM polymyxin B at 24 h (log2FC = -1.80 ± 0.42). Conversely, oxidized glutathione (GSSG) was significantly increased by 1.0 mM both polymyxin B (log2FC = 1.38 ± 0.13 at 4 h and 2.09 ± 0.20 at 24 h) and colistin (log2FC = 1.33 ± 0.24 at 24 h). l-Carnitine was significantly decreased by 1.0 mM of both polymyxins at 24 h, as were several key metabolites involved in biosynthesis and degradation of choline and ethanolamine (log2FC ≤ -1); several phosphatidylserines were also increased (log2FC ≥ 1). Polymyxins perturbed key metabolic pathways that maintain cellular redox balance, mitochondrial ß-oxidation, and membrane lipid biogenesis. These mechanistic findings may assist in developing new pharmacokinetic/pharmacodynamic strategies to attenuate the pulmonary toxicities of inhaled polymyxins and in the discovery of new-generation polymyxins.


Assuntos
Antibacterianos , Polimixinas , Antibacterianos/efeitos adversos , Cromatografia Líquida , Colistina , Células Epiteliais , Humanos , Pulmão , Polimixina B/farmacologia , Polimixinas/farmacologia , Espectrometria de Massas em Tandem
4.
Exp Eye Res ; 207: 108586, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33891955

RESUMO

Oxidative stress plays an important role in the pathogenesis of human retinal diseases. Ginkgo biloba products are widely consumed herbal supplements that contain ingredients with anti-oxidant potentials. However, the active agents in ginkgo biloba extracts (GBE) are unclear. This study assessed the anti-oxidant effects of 19 natural compounds isolated from GBE to provide a rational basis for their use in preventing retinal diseases. The compounds were tested in retinal pigment epithelial (RPE) cells subjected to tert-butyl hydroperoxide (t-BHP)-induced oxidative stress. Cell viability and intracellular reactive oxygen species (ROS) were assessed and flow cytometry was used to delineate the cell death profile. The expression of nuclear factor erythroid 2-related factor-2 (Nrf2) was activated in RPE cells by t-BHP accompanied with an activation of Erk1/2 signaling. GBE-derived rutin and procyanidin B2 ameliorated t-BHP-induced cell death and promoted cell viability by suppressing intracellular ROS generation. These agents also enhanced Nrf2 expression with activating Erk1/2 signaling in RPE cells. In contrast, the other compounds tested were minimally active and did not prevent the loss of cell viability elicited by t-BHP. The present findings suggest that rutin and procyanidin B2 may have potential therapeutic values in the prevention of retinal diseases induced by oxidative damage.


Assuntos
Biflavonoides/farmacologia , Catequina/farmacologia , Ginkgo biloba/química , Sistema de Sinalização das MAP Quinases/fisiologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Proantocianidinas/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Rutina/farmacologia , Antioxidantes/farmacologia , Western Blotting , Sobrevivência Celular , Células Cultivadas , Citometria de Fluxo , Humanos , Potencial da Membrana Mitocondrial , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/metabolismo , terc-Butil Hidroperóxido/toxicidade
5.
Acta Pharmacol Sin ; 42(2): 179-188, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32601365

RESUMO

Uveal melanoma (UM) is a rare ocular tumor. The loss of BRCA1-associated protein 1 (BAP1) and the aberrant activation of G protein subunit alpha q (GNAQ)/G protein subunit alpha 11 (GNA11) contribute to the frequent metastasis of UM. Thus far, limited molecular-targeted therapies have been developed for the clinical treatment of UM. However, an increasing number of studies have revealed the close relationship between the ubiquitin proteasome system (UPS) and the malignancy of UM. UPS consists of a three-enzyme cascade, i.e. ubiquitin-activating enzymes (E1s); ubiquitin-conjugating enzymes (E2s); and ubiquitin-protein ligases (E3s), as well as 26S proteasome and deubiquitinases (DUBs), which work coordinately to dictate the fate of intracellular proteins through regulating ubiquitination, thus influencing cell viability. Due to the critical role of UPS in tumors, we here provide an overview of the crosstalk between UPS and the malignancy of UM, discuss the current UPS-targeted therapies in UM and highlight its potential in developing novel regimens for UM.


Assuntos
Melanoma/terapia , Terapia de Alvo Molecular , Neoplasias Uveais/terapia , Sobrevivência Celular , Humanos , Melanoma/patologia , Metástase Neoplásica , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Ubiquitinação , Neoplasias Uveais/patologia
6.
Planta Med ; 87(7): 511-527, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33761574

RESUMO

Retinal diseases are a leading cause of impaired vision and blindness but some lack effective treatments. New therapies are required urgently to better manage retinal diseases. Natural pentacyclic triterpenoids and their derivatives have a wide range of activities, including antioxidative, anti-inflammatory, cytoprotective, neuroprotective, and antiangiogenic properties. Pentacyclic triterpenoids have great potential in preventing and/or treating retinal pathologies. The pharmacological effects of pentacyclic triterpenoids are often mediated through the modulation of signalling pathways, including nuclear factor erythroid-2 related factor 2, high-mobility group box protein 1, 11ß-hydroxysteroid dehydrogenase type 1, and Src homology region 2 domain-containing phosphatase-1. This review summarizes recent in vitro and in vivo evidence for the pharmacological potential of pentacyclic triterpenoids in the prevention and treatment of retinal diseases. The present literature supports the further development of pentacyclic triterpenoids. Future research should now attempt to improve the efficacy and pharmacokinetic behaviour of the agents, possibly by the use of medicinal chemistry and targeted drug delivery strategies.


Assuntos
Doenças Retinianas , Triterpenos , Anti-Inflamatórios , Humanos , Triterpenos Pentacíclicos/farmacologia , Doenças Retinianas/tratamento farmacológico , Doenças Retinianas/prevenção & controle , Transdução de Sinais , Triterpenos/farmacologia
7.
J Biochem Mol Toxicol ; 34(8): e22513, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32304147

RESUMO

Methotrexate (MTX), one of the important disease-modifying anti-rheumatic drugs, is the first-line drug for rheumatoid arthritis (RA) treatment. However, its adverse drug effects (ADEs) often lead to the abortion of MTX therapy. Human organic anion-transporting polypeptide 1A2 (OATP1A2, also referred as OATP-A or OATP1) encoded by SLCO1A2 gene is an important isoform of the solute carrier transporter (SLC) family. It is known to participate in the cellular uptake of MTX. In our previous study, we identified four OATP1A2 natural variants (E184K, D185N, T259P, and D288N) with impaired MTX uptake activity. This study aimed to evaluate the association of the SLCO1A2 genetic variations encoding these OATP1A2 variants and MTX-related toxicity in RA patients. A total of 60 RA patients were genotyped for these four polymorphisms (G550A, G553A, A775C, and G862A). The association between SLCO1A2 genetic variations and MTX toxicity was analyzed by binary logistic regression analysis. Single nucleotide polymorphisms (SNPs) analysis revealed that A775C and G862A SNPs were not detected in RA patients enrolled in this study, and the presence of 550AA genotype was associated with a high risk of MTX ADEs. Haplotype analysis revealed that H3 (H3 = AG) showed a high risk of MTX ADEs. Furthermore, there was a significant association of 550AA genotype and impaired MTX disposition, which might be the cause of the increased incidence of MTX ADEs in RA patients. Therefore, genetic variations in SLCO1A2 gene are risk factors for MTX toxicity and its information contributes to the prediction of MTX-related toxicity in RA treatment.


Assuntos
Artrite Reumatoide , Metotrexato , Mutação de Sentido Incorreto , Transportadores de Ânions Orgânicos/genética , Polimorfismo de Nucleotídeo Único , Idoso , Substituição de Aminoácidos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Feminino , Humanos , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Pessoa de Meia-Idade
8.
Exp Cell Res ; 383(1): 111509, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31344390

RESUMO

Müller cells are the predominant retinal glial cells. One of the key roles of Müller cells is in the uptake of the neurotransmitter glutamate and in its conversion to glutamine. Müller cell dysfunction due to oxidative stress elicited by high glutamate concentrations can lead to toxicity, which promote the pathogenesis of retinal diseases like diabetic retinopathy and glaucoma. This study investigated the anti-oxidant activity and mechanisms of betulinic acid (BA) and its derivatives in human Müller cells. Human MIO-M1 Müller cells were pre-treated in the presence or absence of BA, BE as well as their derivatives (named H3-H20) followed by incubation with glutamate. Cell viability was evaluated with the MTT and calcein-AM assays. Reactive oxygen species (ROS) production in MIO-M1 cells was measured using CM-H2DCFDA and flow cytometry. The activation of cellular apoptosis and necrosis was analyzed with annexin V/PI staining and flow cytometry. The modulation of signaling pathways involved in glutamate-mediated cytotoxicity and ROS production was evaluated by immunoblotting. The BA derivatives H3, H5 and H7 exhibited minimal cytotoxicity and significant anti-oxidant activity. These compounds significantly suppressed ROS production and attenuated cellular necrosis elicited by glutamate-induced oxidative stress. The protective effects of H3, H5 and H7 in MIO-M1 cells were associated with the attenuation of Akt, Erk, and JNK signaling. The BA analogues H3, H5 and H7 are protective against glutamate-induced oxidative stress in human Müller cells, and elicit their actions by modulation of the Erk, Akt and JNK signaling pathways. These agents are potential candidate molecules for the prevention or treatment of human retinal diseases.


Assuntos
Apoptose/efeitos dos fármacos , Células Ependimogliais/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Triterpenos/farmacologia , Células Cultivadas , Células Ependimogliais/metabolismo , Células Ependimogliais/patologia , Humanos , Triterpenos Pentacíclicos , Espécies Reativas de Oxigênio/metabolismo , Ácido Betulínico
9.
J Antimicrob Chemother ; 74(1): 48-57, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30357331

RESUMO

Background: Current inhaled polymyxin therapy is empirical and often large doses are administered, which can lead to pulmonary adverse effects. There is a dearth of information on the mechanisms of polymyxin-induced lung toxicity and their intracellular localization in lung epithelial cells. Objectives: To investigate the intracellular localization of polymyxins in human lung epithelial A549 cells. Methods: A549 cells were treated with polymyxin B and intracellular organelles (early and late endosomes, endoplasmic reticulum, mitochondria, lysosomes and autophagosomes), ubiquitin protein and polymyxin B were visualized using immunostaining and confocal microscopy. Fluorescence intensities of the organelles and polymyxin B were quantified and correlated for co-localization using ImageJ and Imaris platforms. Results: Polymyxin B co-localized with early endosomes, lysosomes and ubiquitin at 24 h. Significantly increased lysosomal activity and the autophagic protein LC3A were observed after 0.5 and 1.0 mM polymyxin B treatment at 24 h. Polymyxin B also significantly co-localized with mitochondria (Pearson's R = 0.45) and led to the alteration of mitochondrial morphology from filamentous to fragmented form (n = 3, P < 0.001). These results are in line with the polymyxin-induced activation of the mitochondrial apoptotic pathway observed in A549 cells. Conclusions: Accumulation of polymyxins on mitochondria probably caused mitochondrial toxicity, resulting in increased oxidative stress and cell death. The formation of autophagosomes and lysosomes was likely a cellular response to the polymyxin-induced stress and played a defensive role by disassembling dysfunctional organelles and proteins. Our study provides new mechanistic information on polymyxin-induced lung toxicity, which is vital for optimizing inhaled polymyxins in the clinic.


Assuntos
Células Epiteliais Alveolares/química , Antibacterianos/análise , Organelas/química , Polimixinas/análise , Células A549 , Humanos , Microscopia Confocal
10.
Exp Eye Res ; 180: 92-101, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30578788

RESUMO

The Retinal Pigment Epithelium (RPE) is a monolayer of cells located above the choroid. It mediates human visual cycle and nourishes photoreceptors. Hypoxia-induced oxidative stress to RPE is a vital cause of retinal degeneration such as the Age-related Macular Degeneration. Most of these retinal diseases are irreversible with no efficient treatment, therefore protecting RPE cells from hypoxia stress is an important way to prevent or slow down the progression of retinal degeneration. Betulinic acid (BA) and betulin (BE) are pentacyclic triterpenoids with anti-oxidative property, but little is known about their effect on RPE cells. We investigated the protective effect of BA, BE and their derivatives against cobalt chloride-induced hypoxia stress in RPE cells. Human ARPE-19 cells were exposed to BA, BE and their eighteen derivatives (named as H3H20) that we customized through replacing moieties at C3 and C28 positions. We found that cobalt chloride reduced cell viability, increased Reactive Oxygen Species (ROS) production as well as induced apoptosis and necrosis in ARPE-19 cells. Interestingly, the pretreatment of 3-O-acetyl-glycyl- 28-O-glycyl-betulinic acid effectively protected cells from acute hypoxia stress induced by cobalt chloride. Our immunoblotting results suggested that this derivative attenuated the cobalt chloride-induced activation of Akt, Erk and JNK pathways. All findings were further validated in human primary RPE cells. In summary, this BA derivate has protective effect against the acute hypoxic stress in human RPE cells and may be developed into a candidate agent effective in the prevention of prevalent retinal diseases.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Hipóxia/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Triterpenos/farmacologia , Doença Aguda , Adulto , Idoso , Antimutagênicos/toxicidade , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular , Cobalto/toxicidade , Citoproteção , Humanos , Hipóxia/metabolismo , Pessoa de Meia-Idade , Triterpenos Pentacíclicos , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Ácido Betulínico
11.
Angew Chem Int Ed Engl ; 58(28): 9479-9484, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31067353

RESUMO

Inspired by DNA photolyase, a non-natural photoenzymatic catalysis of common flavoproteins is developed for controlled radical polymerization under irradiation of visible light. This photoenzymatic polymerization is highly efficient under mild conditions, applicable to various monomer families, suitable for both homogeneous and heterogeneous media, and can be externally modulated by switching light on and off. A unique combination of the natural enzymatic deoxygenation with the non-natural photoenzymatic process enables an unprecedented oxygen-tolerant, visible-light-controlled radical polymerization using a single enzyme to be developed. Visible light activation of non-natural catalytic functions of the widely distributed flavoproteins is an exciting conceptual advance and may uncover a hitherto underexplored field of photoenzymatic catalysis.


Assuntos
Desoxirribodipirimidina Fotoliase/genética , Catálise , Humanos , Polimerização
12.
Mol Pharmacol ; 94(6): 1412-1420, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30348897

RESUMO

The organic anion transporting polypeptides (OATPs) are important membrane proteins that mediate the cellular uptake of drugs and endogenous substances. OATP1A2 is widely distributed in many human tissues that are targeted in drug therapy; defective OATP1A2 leads to altered drug disposition influencing therapeutic outcomes. 5'-AMP-activated protein kinase (AMPK) signaling plays an important role in the pathogenesis of the metabolic syndrome characterized by an increased incidence of type II diabetes and nonalcoholic fatty liver disease. This study investigated the regulatory role of AMPK in OATP1A2 transport function and expression. We found that the treatment of AMPK-specific inhibitor compound C (dorsomorphin dihydrochloride) decreased OATP1A2-mediated uptake of estrone-3-sulfate in a concentration- and time-dependent manner. The impaired OATP1A2 function was associated with a reduced Vmax [154.6 ± 17.9 pmol × (µg × 4 minutes)-1 in compound C-treated cells vs. 413.6 ± 52.5 pmol × (µg × 4 minutes)-1 in controls]; the Km was unchanged. The cell-surface expression of OATP1A2 was decreased by compound C treatment, but total cellular expression was unchanged. The impaired cell-surface expression of OATP1A2 was associated with accelerated internalization and impaired targeting/recycling. Silencing of the AMPK α1-subunit using specific small interfering RNA corroborated the findings with compound C and revealed a role for AMPK in regulating OATP1A2 protein stability. Overall, this study implicated AMPK in the regulation of the function and expression of OATP1A2, which potentially impacts on the disposition of OATP1A2 drug substrates that may be used to treat patients with the metabolic syndrome and other diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Tipo 2/metabolismo , Estrona/análogos & derivados , Estrona/farmacologia , Células HEK293 , Humanos , Estabilidade Proteica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
13.
Exp Eye Res ; 175: 173-180, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29913166

RESUMO

Müller cells are the primary glia in the retina, playing a critical role in retinal homeostasis and retinal pathology. This study evaluated the canonical Wnt signalling pathway and its downstream effects on retinal degeneration in a transgenic mouse model of inducible Müller cell disruption. Increased expression of the LacZ reporter gene in the retina suggested Wnt signalling had been activated after induced Müller cell disruption. Activation was validated by observing nuclear translocation of ß-Catenin. The mRNA expression of 80 Wnt related genes were assessed using real-time PCR. The Wnt signalling inhibitors Dkk1, Dkk3 and sFRP3 were significantly downregulated. Furthermore, the ubiquitin-mediated ß-Catenin proteolysis genes ß-TrCP and SHFM3, were also significantly downregulated. The downstream target genes of the Wnt signalling, including Fra1, CyclinD2 and C-Myc were upregulated. The changes of these genes at the protein level were validated by Western blot. Their distributions in the retina were evaluated by immunofluorescent staining. Our findings indicate that Müller cells are involved in retinal Wnt signalling. Activation of Wnt signalling and its downstream target genes may play important roles in photoreceptor degeneration and neovascularization occurring in the retina after induced disruption of Müller cells.


Assuntos
Células Ependimogliais/patologia , Regulação da Expressão Gênica/fisiologia , Degeneração Retiniana/genética , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Western Blotting , Quimiocinas , Proteínas F-Box/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Degeneração Retiniana/patologia , Proteínas Contendo Repetições de beta-Transducina/genética
14.
Eur J Clin Pharmacol ; 74(12): 1575-1584, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30167756

RESUMO

BACKGROUND: Actinomycin D is used for treatment of paediatric cancers; however, a large inter-patient pharmacokinetic (PK) variability and hepatotoxicity are significant limitations to its use and warrant further investigation. Elimination of actinomycin D may be mediated by transporters, as the drug does not seem to undergo significant metabolism. We investigated the role of solute carrier (SLC) transporters in actinomycin D PK. METHODS: Fourteen key SLCs were screened through probe substrate uptake inhibition by actinomycin D in HEK293 cells. Uptake of actinomycin D was further studied in candidate SLCs by measuring intracellular actinomycin D using a validated LCMS assay. Pharmacogenetic analysis was conducted for 60 patients (Clinical trial: NCT00900354), who were genotyped for SNPs for OAT4 and PEPT2. RESULTS: OAT4, OCT2, OCT3 and PEPT2 showed significantly lower probe substrate uptake (mean ± SD 75.0 ± 3.5% (p < 0.0001), 74.8 ± 11.2% (p = 0.001), 81.2 ± 14.0% (p = 0.0083) and 70.7 ± 5.7% (p = 0.0188)) compared to that of control. Intracellular accumulation of actinomycin D was greater compared to vector control in OAT4-transfected cells by 1.5- and 1.4-fold at 10 min (p = 0.01) and 20 min (p = 0.03), and in PEPT2-transfected cells by 1.5- and 1.7-fold at 10 min (p = 0.047) and 20 min (p = 0.043), respectively. Subsequent clinical study did not find a significant association between OAT4 rs11231809 and PEPT2 rs2257212 genotypes, and actinomycin D PK parameters such as clearance (CL) and volume of distribution (Vd). CONCLUSION: Transport of actinomycin D was mediated by OAT4 and PEPT2 in vitro. There was a lack of clinical significance of OAT4 and PEPT2 genotypes as predictors of actinomycin D disposition in paediatric cancer patients.


Assuntos
Antibióticos Antineoplásicos/farmacocinética , Proteínas de Transporte/metabolismo , Dactinomicina/farmacocinética , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Adolescente , Antibióticos Antineoplásicos/uso terapêutico , Transporte Biológico , Criança , Pré-Escolar , Dactinomicina/uso terapêutico , Genótipo , Células HEK293 , Humanos , Lactente , Recém-Nascido , Resultados Negativos , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Farmacogenética , Polimorfismo de Nucleotídeo Único/genética , Valor Preditivo dos Testes , Simportadores/genética , Simportadores/metabolismo , Adulto Jovem
15.
J Biochem Mol Toxicol ; 32(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28960612

RESUMO

Ziyuglycoside I (Ziyu I), one of the major components isolated from the root of Sanguisorba officinalis L., has been proved for the antitumor properties on oral cancer, prostate cancer, and colorectal cancer. However, the effect of Ziyu I on retinoblastoma (RB) is not well understood. In this study, we investigated the inhibitory effect and underlying molecular mechanism of Ziyu I on human RB WERI-Rb-1 cells. Our results indicated that Ziyu I could suppress cell viability and induce mitochondrial-dependent cell apoptosis in WERI-Rb-1 cells. Furthermore, Ziyu I treatment increased p53 expression as well as improved p53 stabilization through downregulation of pS166-Mdm2 and upregulation of phosphorylated- and acetylated-p53. Blockade of p53 significantly attenuated Ziyu I-induced mitochondrial dysfunction. Our findings demonstrate that Ziyu I exhibits excellent anticancer effect on human RB WERI-Rb-1 cells by triggering p53 activation, and imply Ziyu I as a potential compound for chemotherapy of human RB.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias da Retina/tratamento farmacológico , Retinoblastoma/tratamento farmacológico , Saponinas/farmacologia , Proteína Supressora de Tumor p53/agonistas , Acetilação/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Interferência de RNA , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Neoplasias da Retina/metabolismo , Neoplasias da Retina/patologia , Retinoblastoma/metabolismo , Retinoblastoma/patologia , Serina/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
16.
Exp Cell Res ; 359(1): 120-128, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28780307

RESUMO

It is estimated that abnormal accumulation of all-trans-retinal (atRAL) is a leading cause of photoreceptor degeneration in retinal degenerative diseases. Deficiency of interphotoreceptor retinoid-binding protein (IRBP), a retinoid transporter in the visual cycle, is responsible for the impaired clearance of atRAL and results in atRAL toxicity in retina. Therefore, IRBP has been proposed to be a potent target in preventing atRAL-induced photoreceptor degeneration. In this study, the neuroprotective effect of tetramethylpyrazine (TMP) against atRAL toxicity in the differentiated Y-79 cells, a in vitro model of photoreceptor, was first investigated. Our findings showed that atRAL could induce cytotoxicity, oxidative/nitrosative stresses, apoptosis and leukostasis in the differentiated Y-79 cells; however, the pre-treatment of TMP significantly attenuated such effects in a dose-dependent manner. Furthermore, our results indicated that TMP exerted its neuroprotective effect mainly through upregulating IRBP expression. The present study significantly contributes to better understanding the important role of IRBP in retinal degenerative diseases and forms the basis of the therapeutic development of TMP in such diseases in the future.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proteínas do Olho/metabolismo , Fármacos Neuroprotetores/farmacologia , Pirazinas/farmacologia , Retinaldeído/toxicidade , Proteínas de Ligação ao Retinol/metabolismo , Regulação para Cima/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Leucostasia/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Neuroproteção/efeitos dos fármacos , Nitrosação , Estresse Oxidativo/efeitos dos fármacos , Molécula 1 de Adesão de Célula Vascular/metabolismo
17.
Exp Cell Res ; 357(2): 335-340, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28583762

RESUMO

Amyloid ß (Aß) is a critical stimulator that promotes the progression of age-related macular degeneration (AMD). NLRP3 inflammasome activation induced by Aß is estimated to be responsible for retinal pigment epithelium (RPE) dysfunction in such disease. Puerarin, one of the major active constituents of Kudzu root, has been widely used in the clinical treatment of AMD in China for decades; however, the detailed molecular mechanism remains far from clear. In this study, we investigated the protective effect and underlying mechanism of puerarin against Aß1-40-induced NLRP3 inflammasome activation in LPS-primed ARPE-19 cells. The results showed that Aß1-40 induced NLRP3 inflammasome activation mainly via triggering ROS-dependent oxidative stress, particularly lipid peroxidation, and endoplasmic reticulum stress in LPS-primed ARPE-19 cells; however, such effect could be significantly reversed by puerarin in a dose-dependent manner. Furthermore, the effect of puerarin was potentially mediated through activating Nrf2/HO-1 antioxidant signaling pathway and inhibiting Aß1-40-induced phosphorylation of IRE1 and PERK as well as nuclear expression of ATF6α. Therefore, the significance of the current study is to reveal the novel mechanism of puerarin in the prevention of AMD.


Assuntos
Antioxidantes/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Inflamassomos/efeitos dos fármacos , Isoflavonas/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Peptídeos beta-Amiloides/farmacologia , Proteínas de Transporte/metabolismo , Células Epiteliais/metabolismo , Humanos , Inflamassomos/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/metabolismo
18.
Xenobiotica ; 48(2): 197-205, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28093031

RESUMO

1. Human solute carrier transporters (SLCs) are important membrane proteins mediate the cellular transport of many endogenous and exogenous substances. Organic anion/cation transporters (OATs/OCTs) and organic anion transporting polypeptides (OATPs) are essential SLCs involved in drug influx. Drug-drug/herb interactions through competing for specific SLCs often lead to unsatisfied therapeutic outcomes and/or unwanted side effects. In this study, we comprehensively investigated the inhibitory effects of five clinically relevant alkaloids (dendrobine, matrine, oxymatrine, tryptanthrin and chelerythrine) on the substrate transport through several OATs/OCTs and OATPs. 2. We performed transport functional assay and kinetic analysis on the HEK-293 cells over-expressing each SLC gene. 3. Our data showed tryptanthrin significantly inhibited the transport activity of OAT3 (IC50 = 0.93 ± 0.22 µM, Ki = 0.43 µM); chelerythrine acted as a potent inhibitor to the substrate transport mediated through OATP1A2 (IC50 = 0.63 ± 0.43 µM, Ki = 0.60 µM), OCT1 (IC50 = 13.60 ± 2.81 µM) and OCT2 (IC50 =10.80 ± 1.16 µM). 4. Our study suggested tryptanthrin and chelerythrine could potently impact on the drug transport via specific OATs/OCTs. Therefore, the co-administration of these alkaloids with drugs could have clinical consequences due to drug-drug/herb interactions. Precautions should be warranted in the multi-drug therapies involving these alkaloids.


Assuntos
Alcaloides/farmacologia , Transporte Biológico/efeitos dos fármacos , Transportadores de Ânions Orgânicos/metabolismo , Interações Medicamentosas , Células HEK293 , Humanos , Quinolizinas/farmacologia , Matrinas
19.
Acta Biochim Biophys Sin (Shanghai) ; 50(9): 914-920, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30060118

RESUMO

Carboplatin is the most commonly used drug in the first-line treatment of human retinoblastoma (RB), but its clinical application is greatly limited due to acquired drug resistance upon the long-term treatment. Forkhead box protein M1 (FoxM1) is the transcription factor aberrantly expressed in various types of human cancers, which plays an essential role in the regulation of tumorigenesis, tumor metastasis and drug resistance. However, little is known about the role of FoxM1 in chemo-resistance of human RB. In this study, we investigated the regulatory effect of FoxM1 on carboplatin resistance in human RB Y-79 cells and carboplatin-resistant Y-79 (Y-79CR) cells, as well as the possible mechanism. Our results showed that FoxM1 was up-regulated in Y-79CR cells and silencing of FoxM1 promoted carboplatin sensitivity and accumulation, while overexpression of FoxM1 in Y-79 cells performed oppositely. Our study further revealed that FoxM1 enhanced carboplatin resistance in Y-79CR cells through directly up-regulating the transcription of ATP-binding cassette transporter C4 (ABCC4), an important drug efflux transporter. Overall, our study demonstrated the novel role of FoxM1-ABCC4 axis in human RB, which provides insights into the prevention of carboplatin resistance in human RB.


Assuntos
Carboplatina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteína Forkhead Box M1/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Relação Dose-Resposta a Droga , Proteína Forkhead Box M1/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Interferência de RNA , Retinoblastoma/genética , Retinoblastoma/metabolismo , Retinoblastoma/patologia , Regulação para Cima
20.
Artigo em Inglês | MEDLINE | ID: mdl-28416543

RESUMO

Inhaled polymyxins are of considerable utility in achieving optimal exposure in the respiratory tract for the treatment of lung infections caused by multidrug-resistant Gram-negative pathogens. Current inhaled polymyxin therapy is empirical, and often large doses are used that may lead to potential pulmonary adverse effects. This study aimed to investigate the effect of polymyxins on human lung epithelial (A549) cells. The viability of A549 cells was examined after treatment with polymyxins by flow cytometry. Activation of caspases 3, 8, and 9, expression of Fas ligand (FasL), loss of mitochondrial membrane potential, and mitochondrial oxidative stress induced by polymyxin B were evaluated. The concentration of polymyxin B required to induce 50% of maximal cell death was 1.74 mM (95% confidence interval, 1.60 to 1.90 mM). Colistin was at least 2-fold less toxic than polymyxin B, while colistimethate was nontoxic. With 2.0 mM polymyxin B, 30.6% ± 11.5% (mean ± standard deviation) of the cells were apoptotic at 8 h and this increased to 71.3% ± 3.72% at 24 h. Concentration- and time-dependent activation of caspases 3, 8, and 9 was evident, while the activation of caspase 9 was more dramatic. Furthermore, polymyxin B caused concentration- and time-dependent FasL expression, production of mitochondrial reactive oxygen species, and changes in mitochondrial membrane potential. This is the first study to demonstrate that both extrinsic death receptor and intrinsic mitochondrial pathways are involved in polymyxin-induced toxicity in A549 cells. This knowledge base is critical for the development of novel strategies for the safe and effective inhalation therapy of polymyxins against Gram-negative "superbugs."


Assuntos
Polimixinas/efeitos adversos , Polimixinas/farmacologia , Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Colistina/efeitos adversos , Colistina/análogos & derivados , Colistina/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Polimixina B/efeitos adversos , Polimixina B/farmacologia
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