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1.
PLoS Pathog ; 18(1): e1010271, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35061864

RESUMO

Flavivirus infection of cells induces massive rearrangements of the endoplasmic reticulum (ER) membrane to form viral replication organelles (ROs) which segregates viral RNA replication intermediates from the cytoplasmic RNA sensors. Among other viral nonstructural (NS) proteins, available evidence suggests for a prominent role of NS4B, an ER membrane protein with multiple transmembrane domains, in the formation of ROs and the evasion of the innate immune response. We previously reported a benzodiazepine compound, BDAA, which specifically inhibited yellow fever virus (YFV) replication in cultured cells and in vivo in hamsters, with resistant mutation mapped to P219 of NS4B protein. In the following mechanistic studies, we found that BDAA specifically enhances YFV induced inflammatory cytokine response in association with the induction of dramatic structural alteration of ROs and exposure of double-stranded RNA (dsRNA) in virus-infected cells. Interestingly, the BDAA-enhanced cytokine response in YFV-infected cells is attenuated in RIG-I or MAD5 knockout cells and completely abolished in MAVS knockout cells. However, BDAA inhibited YFV replication at a similar extent in the parent cells and cells deficient of RIG-I, MDA5 or MAVS. These results thus provided multiple lines of biological evidence to support a model that BDAA interaction with NS4B may impair the integrity of YFV ROs, which not only inhibits viral RNA replication, but also promotes the release of viral RNA from ROs, which consequentially activates RIG-I and MDA5. Although the innate immune enhancement activity of BDAA is not required for its antiviral activity in cultured cells, its dual antiviral mechanism is unique among all the reported antiviral agents thus far and warrants further investigation in animal models in future.


Assuntos
Antivirais/farmacologia , Benzodiazepinas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Vírus da Febre Amarela/efeitos dos fármacos , Linhagem Celular , Proteína DEAD-box 58/imunologia , Humanos , Imunidade Inata/imunologia , Proteínas não Estruturais Virais/efeitos dos fármacos , Febre Amarela/imunologia , Vírus da Febre Amarela/imunologia
2.
Drug Metab Dispos ; 47(8): 890-898, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31167838

RESUMO

Preliminary analysis of ongoing birth surveillance study identified evidence of potential increased risk for neural tube defects (NTDs) in newborns associated with exposure to dolutegravir at the time of conception. Folate deficiency is a common cause of NTDs. Dolutegravir and other HIV integrase inhibitor drugs were evaluated in vitro for inhibition of folate transport pathways: proton-coupled folate transporter (PCFT), reduced folate carrier (RFC), and folate receptor α (FRα)-mediated endocytosis. Inhibition of folate transport was extrapolated to the clinic by using established approaches for transporters in intestine, distribution tissues, and basolateral and apical membranes of renal proximal tubules (2017 FDA Guidance). The positive controls, methotrexate and pemetrexed, demonstrated clinically relevant inhibition of PCFT, RFC, and FRα in folate absorption, distribution, and renal sparing. Valproic acid was used as a negative control that elicits folate-independent NTDs; valproic acid did not inhibit PCFT, RFC, or FRα At clinical doses and exposures, the observed in vitro inhibition of FRα by dolutegravir and cabotegravir was not flagged as clinically relevant; PCFT and RFC inhibition was not observed in vitro. Bictegravir inhibited both PCFT and FRα, but the observed inhibition did not reach the criteria for clinical relevance. Elvitegravir and raltegravir inhibited PCFT, but only raltegravir inhibition of intestinal PCFT was flagged as potentially clinically relevant at the highest 1.2-g dose (not the 400-mg dose). These studies showed that dolutegravir is not a clinical inhibitor of folate transport pathways, and it is not predicted to elicit clinical decreases in maternal and fetal folate levels. Clinically relevant HIV integrase inhibitor drug class effect on folate transport pathways was not observed. SIGNIFICANCE STATEMENT: Preliminary analysis of ongoing birth surveillance study identified evidence of potential increased risk for neural tube defects (NTDs) in newborns associated with exposure to the HIV integrase inhibitor dolutegravir at the time of conception; folate deficiency is a common cause of NTDs. Dolutegravir and other HIV integrase inhibitor drugs were evaluated in vitro for inhibition of the major folate transport pathways: proton-coupled folate transporter, reduced folate carrier, and folate receptor α-mediated endocytosis. The present studies showed that dolutegravir is not a clinical inhibitor of folate transport pathways, and it is not predicted to elicit clinical decreases in maternal and fetal folate levels. Furthermore, clinically relevant HIV integrase inhibitor drug class effect on folate transport pathways was not observed.


Assuntos
Ácido Fólico/metabolismo , Inibidores de Integrase de HIV/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Transdução de Sinais/efeitos dos fármacos , Animais , Cães , Endocitose/efeitos dos fármacos , Ensaios Enzimáticos , Feminino , Receptor 1 de Folato/metabolismo , Ácido Fólico/sangue , Deficiência de Ácido Fólico/induzido quimicamente , Deficiência de Ácido Fólico/complicações , Deficiência de Ácido Fólico/epidemiologia , Infecções por HIV/tratamento farmacológico , Humanos , Incidência , Recém-Nascido , Células Madin Darby de Rim Canino , Exposição Materna/efeitos adversos , Troca Materno-Fetal , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/etiologia , Oxazinas , Piperazinas , Gravidez , Transportador de Folato Acoplado a Próton/metabolismo , Piridonas , Proteína Carregadora de Folato Reduzido/metabolismo , Medição de Risco
3.
J Virol ; 90(23): 10774-10788, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27654301

RESUMO

Although a highly effective vaccine is available, the number of yellow fever cases has increased over the past 2 decades, which highlights the pressing need for antiviral therapeutics. In a high-throughput screening campaign, we identified an acetic acid benzodiazepine (BDAA) compound which potently inhibits yellow fever virus (YFV). Interestingly, while treatment of YFV-infected cultures with 2 µM BDAA reduced the virion production by greater than 2 logs, the compound was not active against 21 other viruses from 14 different viral families. Selection and genetic analysis of drug-resistant viruses revealed that replacement of the proline at amino acid 219 (P219) of the nonstructural protein 4B (NS4B) with serine, threonine, or alanine conferred YFV with resistance to BDAA without apparent loss of replication fitness in cultured mammalian cells. However, replacement of P219 with glycine conferred BDAA resistance with significant loss of replication ability. Bioinformatics analysis predicts that the P219 amino acid is localized at the endoplasmic reticulum lumen side of the fifth putative transmembrane domain of NS4B, and the mutation may render the viral protein incapable of interacting with BDAA. Our studies thus revealed an important role and the structural basis for the NS4B protein in supporting YFV replication. Moreover, in YFV-infected hamsters, oral administration of BDAA protected 90% of the animals from death, significantly reduced viral load by greater than 2 logs, and attenuated virus infection-induced liver injury and body weight loss. The encouraging preclinical results thus warrant further development of BDAA or its derivatives as antiviral agents to treat yellow fever. IMPORTANCE Yellow fever is an acute viral hemorrhagic disease which threatens approximately 1 billion people living in tropical areas of Africa and Latin America. Although a highly effective yellow fever vaccine has been available for more than 7 decades, the low vaccination rate fails to prevent outbreaks in at-risk regions. It has been estimated that up to 1.7 million YFV infections occur in Africa each year, resulting in 29,000 to 60,000 deaths. Thus far, there is no specific antiviral treatment for yellow fever. To cope with this medical challenge, we identified a benzodiazepine compound that selectively inhibits YFV by targeting the viral NS4B protein. To our knowledge, this is the first report demonstrating in vivo safety and antiviral efficacy of a YFV NS4B inhibitor in an animal model. We have thus reached a critical milestone toward the development of specific antiviral therapeutics for clinical management of yellow fever.

4.
Drug Metab Dispos ; 43(4): 485-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25605813

RESUMO

Serum creatinine is commonly used as a marker of renal function, but increases in serum creatinine might not represent changes in glomerular filtration rate (GFR). INCB039110 (2-(3-(4-(7H-pyrrolo[2,3-day]pyrimidin-4-yl)-1H-pyrazol-1-yl)-1-(1-(3-fluoro-2-(trifluoromethyl)isonicotinoyl)piperidin-4-yl)azetidin-3-yl)acetonitrile) is an inhibitor of the Janus kinases (JAKs) with selectivity for JAK1. In a phase 1 study, a modest and reversible increase in serum creatinine was observed after treatment with INCB039110. However, a dedicated renal function study with INCB039110, assessed by iohexol plasma clearance, conducted in healthy volunteers indicated no change in GFR. In vitro studies were therefore conducted to investigate the interaction of INCB039110 with five transporters that are likely involved in the renal clearance of creatinine. Cell systems expressing individual or multiple transporters were used, including a novel quintuple-transporter model OAT2/OCT2/OCT3/MATE1/MATE2-K. INCB039110 potently inhibited OCT2-mediated uptake of creatinine as well as MATE1-/MATE2-K-mediated efflux of creatinine. Given the interactions of INCB039110 with multiple transporters affecting creatinine uptake and efflux, an integrated system expressing all five transporters was sought; in that system, INCB039110 caused a dose-dependent decrease in transcellular transport of creatinine with weaker net inhibition compared with the effects on individual transporters. In summary, a molecular mechanism for the increase in serum creatinine by INCB039110 has been established. These studies also underline the limitations of using serum creatinine as a marker of renal function.


Assuntos
Azetidinas/farmacocinética , Creatinina/sangue , Ácidos Isonicotínicos/farmacocinética , Janus Quinase 1/antagonistas & inibidores , Rim/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Inibidores de Proteínas Quinases/farmacocinética , Adolescente , Adulto , Animais , Azetidinas/administração & dosagem , Azetidinas/química , Azetidinas/farmacologia , Biomarcadores/sangue , Estudos Cross-Over , Cães , Taxa de Filtração Glomerular , Voluntários Saudáveis , Humanos , Ácidos Isonicotínicos/administração & dosagem , Ácidos Isonicotínicos/química , Ácidos Isonicotínicos/farmacologia , Rim/efeitos dos fármacos , Células Madin Darby de Rim Canino , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Estrutura Molecular , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , Proteínas de Transporte de Cátions Orgânicos/genética , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Adulto Jovem
5.
Kidney Int ; 86(2): 350-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24646860

RESUMO

Many xenobiotics including the pharmacoenhancer cobicistat increase serum creatinine by inhibiting its renal active tubular secretion without affecting the glomerular filtration rate. This study aimed to define the transporters involved in creatinine secretion, applying that knowledge to establish the mechanism for xenobiotic-induced effects. The basolateral uptake transporters organic anion transporter OAT2 and organic cation transporters OCT2 and OCT3 were found to transport creatinine. At physiologic creatinine concentrations, the specific activity of OAT2 transport was over twofold higher than OCT2 or OCT3, establishing OAT2 as a likely relevant creatinine transporter and further challenging the traditional view that creatinine is solely transported by a cationic pathway. The apical multidrug and toxin extrusion transporters MATE1 and MATE2-K demonstrated low-affinity and high-capacity transport. All drugs known to affect creatinine inhibited OCT2 and MATE1. Similar to cimetidine and ritonavir, cobicistat had the greatest effect on MATE1 with a 50% inhibition constant of 0.99 µM for creatinine transport. Trimethoprim potently inhibited MATE2-K, whereas dolutegravir preferentially inhibited OCT2. Cimetidine was unique, inhibiting all transporters that interact with creatinine. Thus, the clinical observation of elevated serum creatinine in patients taking cobicistat is likely a result of OCT2 transport, facilitating intracellular accumulation, and MATE1 inhibition.


Assuntos
Carbamatos/farmacologia , Creatinina/sangue , Creatinina/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/antagonistas & inibidores , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Tiazóis/farmacologia , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Células CHO , Linhagem Celular , Células Cultivadas , Cimetidina/farmacologia , Cobicistat , Cricetulus , Cães , Células HEK293 , Humanos , Cinética , Proteínas de Transporte de Cátions Orgânicos/antagonistas & inibidores , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Transportador 2 de Cátion Orgânico , Proteínas Recombinantes/metabolismo
6.
Ther Apher Dial ; 28(1): 112-118, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37853934

RESUMO

INTRODUCTION: We investigated the clinical efficacy and safety of blood purification technology in patients with polymyositis/dermatomyositis. METHODS: In a study of 22 patients, 10 cases received blood purification treatment (5 cases received plasma exchange, 5 cases received plasma HA280 immunoadsorption), and 12 cases served as the control group. A 3-month follow-up was conducted to compare the clinical manifestations and laboratory examination. RESULTS: Symptoms and signs of patients in treatment group were significantly improved, and the hormone usage was lower than the control group. For patients with normal creatine kinase level and ferritin level below three times the upper limit of normal, there was a positive correlation between their N/L values and MDAAT scores. CONCLUSION: The results of this study suggest that blood purification therapy, including plasma HA280 immunoadsorption and plasma exchange, is an effective and safe treatment for patients with polymyositis/dermatomyositis, offering assistance in reducing hormone usage in the long-term.


Assuntos
Dermatomiosite , Polimiosite , Humanos , Dermatomiosite/tratamento farmacológico , Polimiosite/tratamento farmacológico , Troca Plasmática , Plasmaferese , Hormônios/uso terapêutico
7.
Acta Biomater ; 159: 211-225, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36669549

RESUMO

Myocardial hypoxia is the low oxygen tension in the heart tissue implicated in many diseases, including ischemia, cardiac dysfunction, or after heart procurement for transplantation. Oxygen-generating microparticles have recently emerged as a potential strategy for supplying oxygen to sustain cell survival, growth, and tissue functionality in hypoxia. Here, we prepared oxygen-generating microparticles with poly D,L-lactic-co-glycolic acid, and calcium peroxide (CPO), which yielded a continuous morphology capable of sustained oxygen release for up to 24 h. We demonstrated that CPO microparticles increased primary rat cardiomyocyte metabolic activity while not affecting cell viability during hypoxia. Moreover, hypoxia-inducible factor (HIF)-1α, which is upregulated during hypoxia, can be downregulated by delivering oxygen using CPO microparticles. Single-cell traction force microscopy data demonstrated that the reduced energy generated by hypoxic cells could be restored using CPO microparticles. We engineered cardiac tissues that showed higher contractility in the presence of CPO microparticles compared to hypoxic cells. Finally, we observed reduced myocardial injuries in ex vivo rabbit hearts treated with CPO microparticles. In contrast, an acute early myocardial injury was observed for the hearts treated with control saline solution in hypoxia. In conclusion, CPO microparticles improved cell and tissue contractility and gene expression while reducing hypoxia-induced myocardial injuries in the heart. STATEMENT OF SIGNIFICANCE: Oxygen-releasing microparticles can reduce myocardial ischemia, allograft rejection, or irregular heartbeats after heart transplantation. Here we present biodegradable oxygen-releasing microparticles that are capable of sustained oxygen release for more than 24 hrs. We then studied the impact of sustained oxygen release from microparticles on gene expresseion and cardiac cell and tissue function. Previous studies have not measured cardiac tissue or cell mechanics during hypoxia, which is important for understanding proper cardiac function and beating. Using traction force microscopy and an engineered tissue-on-a-chip, we demonstrated that our oxygen-releasing microparticles improve cell and tissue contractility during hypoxia while downregulating the HIF-1α expression level. Finally, using the microparticles, we showed reduced myocardial injuries in rabbit heart tissue, confirming the potential of the particles to be used for organ transplantation or tissue engineering.


Assuntos
Isquemia Miocárdica , Oxigênio , Animais , Coelhos , Ratos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isquemia , Isquemia Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Oxigênio/metabolismo
8.
Adv Healthc Mater ; 11(12): e2102593, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35191610

RESUMO

Periodontal disease begins as an inflammatory response to a bacterial biofilm deposited around the teeth, which over time leads to the destruction of tooth-supporting structures and consequently tooth loss. Conventional treatment strategies show limited efficacy in promoting regeneration of damaged periodontal tissues. Here, a delivery platform is developed for small extracellular vesicles (sEVs) derived from gingival mesenchymal stem cells (GMSCs) to treat periodontitis. EVs can achieve comparable therapeutic effects to their cells of origin. However, the short half-lives of EVs after their administration along with their rapid diffusion away from the delivery site necessitate frequent administration to achieve therapeutic benefits. To address these issues, "dual delivery" microparticles are engineered enabling microenvironment-sensitive release of EVs by metalloproteinases at the affected site along with antibiotics to suppress bacterial biofilm growth. GMSC sEVs are able to decrease the secretion of pro-inflammatory cytokines by monocytes/macrophages and T cells, suppress T-cell activation, and induce the formation of T regulatory cells (Tregs) in vitro and in a rat model of periodontal disease. One-time administration of immunomodulatory GMSC sEV-decorated microparticles leads to a significant improvement in regeneration of the damaged periodontal tissue. This approach will have potential clinical applications in the regeneration of a variety of tissues.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Doenças Periodontais , Animais , Doenças Periodontais/terapia , Periodonto , Ratos , Células-Tronco
9.
Matter ; 5(2): 666-682, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35340559

RESUMO

Periodontal diseases are caused by microbial infection and the recruitment of destructive immune cells. Current therapies mainly deal with bacteria elimination, but the regeneration of periodontal tissues remains a challenge. Here we developed a modular microneedle (MN) patch that delivered both antibiotic and cytokines into the local gingival tissue to achieve immunomodulation and tissue regeneration. This MN patch included a quickly dissolvable gelatin membrane for an immediate release of tetracycline and biodegradable GelMA MNs that contained tetracycline-loaded poly(lactic-co-glycolic acid) nanoparticles and cytokine-loaded silica microparticles for a sustained release. Antibiotic release completely inhibited bacteria growth, and the release of IL-4 and TGF-ß induced the repolarization of anti-inflammatory macrophages and the formation of regulatory T cells in vitro. In vivo delivery of MN patch into periodontal tissues suppressed proinflammatory factors and promoted pro-regenerative signals and tissue healing, which demonstrated the therapeutic potential of local immunomodulation for tissue regeneration.

10.
Bioorg Med Chem Lett ; 21(21): 6582-5, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21920749

RESUMO

Structure-activity studies have led to a discovery of 3-(4-pyridyl)methyl ether derivative 9d that has 25- to 50-fold greater functional potency than R-baclofen at human and rodent GABA(B) receptors in vitro. Mouse hypothermia studies confirm that this compound crosses the blood-brain barrier and is approximately 50-fold more potent after systemic administration.


Assuntos
Baclofeno/farmacologia , Descoberta de Drogas , Agonistas GABAérgicos/farmacologia , Receptores de GABA-B/efeitos dos fármacos , Animais , Baclofeno/química , Baclofeno/farmacocinética , Barreira Hematoencefálica , Agonistas GABAérgicos/química , Agonistas GABAérgicos/farmacocinética , Humanos , Camundongos
11.
Matter ; 4(5): 1528-1554, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33723531

RESUMO

Infection by SARS-CoV-2 virus often induces the dysregulation of immune responses, tissue damage, and blood clotting. Engineered biomaterials from the nano- to the macroscale can provide targeted drug delivery, controlled drug release, local immunomodulation, enhanced immunity, and other desirable functions to coordinate appropriate immune responses and to repair tissues. Based on the understanding of COVID-19 disease progression and immune responses to SARS-CoV-2, we discuss possible immunotherapeutic strategies and highlight biomaterial approaches from the perspectives of preventive immunization, therapeutic immunomodulation, and tissue healing and regeneration. Successful development of biomaterial platforms for immunization and immunomodulation will not only benefit COVID-19 patients, but also have broad applications for a variety of infectious diseases.

12.
Adv Sci (Weinh) ; 8(7): 2003516, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33854891

RESUMO

Cell reprogramming is considered a stochastic process, and it is not clear which cells are prone to be reprogrammed and whether a deterministic step exists. Here, asymmetric cell division (ACD) at the early stage of induced neuronal (iN) reprogramming is shown to play a deterministic role in generating elite cells for reprogramming. Within one day, fibroblasts underwent ACD, with one daughter cell being converted into an iN precursor and the other one remaining as a fibroblast. Inhibition of ACD significantly inhibited iN conversion. Moreover, the daughter cells showed asymmetric DNA segregation and histone marks during cytokinesis, and the cells inheriting newly replicated DNA strands during ACD became iN precursors. These results unravel a deterministic step at the early phase of cell reprogramming and demonstrate a novel role of ACD in cell phenotype change. This work also supports a novel hypothesis that daughter cells with newly replicated DNA strands are elite cells for reprogramming, which remains to be tested in various reprogramming processes.


Assuntos
Divisão Celular Assimétrica/fisiologia , Reprogramação Celular/fisiologia , Fibroblastos/fisiologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais
13.
Research (Wash D C) ; 2020: 7043124, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32377639

RESUMO

Glutathione S-transferases (GSTs), detoxification enzymes that catalyze the addition of glutathione (GSH) to diverse electrophilic molecules, are often overexpressed in various tumor cells. While fluorescent probes for GSTs have often adopted the 2,4-dinitrobenzenesulfonyl (DNs) group as the receptor unit, they usually suffer from considerable background reaction noise with GSH due to excessive electron deficiency. However, weakening this reactivity is generally accompanied by loss of sensitivity for GSTs, and therefore, finely turning down the reactivity while maintaining certain sensitivity is critical for developing a practical probe. Here, we report a rational semiquantitative strategy for designing such a practical two-photon probe by introducing a parameter adopted from the conceptual density functional theory (CDFT), the local electrophilicity ω k , to characterize this reactivity. As expected, kinetic studies established ω k as efficient to predict the reactivity with GSH, and probe NI3 showing the best performance was successfully applied to detecting GST activities in live cells and tissue sections with high sensitivity and signal-to-noise ratio. Photoinduced electron transfer of naphthalimide-based probes, captured by femtosecond transient absorption for the first time and unraveled by theoretical calculations, also contributes to the negligible background noise.

14.
Chem Sci ; 11(41): 11205-11213, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34094361

RESUMO

The applications of most fluorescent probes available for Glutathione S-Transferases (GSTs), including NI3 which we developed recently based on 1,8-naphthalimide (NI), are limited by their short emission wavelengths due to insufficient penetration. To realize imaging at a deeper depth, near-infrared (NIR) fluorescent probes are required. Here we report for the first time the designing of NIR fluorescent probes for GSTs by employing the NIR fluorophore HCy which possesses a higher brightness, hydrophilicity and electron-deficiency relative to NI. Intriguingly, with the same receptor unit, the HCy-based probe is always more reactive towards glutathione than the NI-based one, regardless of the specific chemical structure of the receptor unit. This was proved to result from the higher electron-deficiency of HCy instead of its higher hydrophilicity based on a comprehensive analysis. Further, with caging of the autofluorescence being crucial and more difficult to achieve via photoinduced electron transfer (PET) for a NIR probe, the quenching mechanism of HCy-based probes was proved to be PET for the first time with femtosecond transient absorption and theoretical calculations. Thus, HCy2 and HCy9, which employ receptor units less reactive than the one adopted in NI3, turned out to be the most appropriate NIR probes with high-sensitivity and little nonenzymatic background noise. They were then successfully applied to detecting GST in cells, tissues and tumor xenografts in vivo. Additionally, unlike HCy2 with a broad isoenzyme selectivity, HCy9 is specific for GSTA1-1, which is attributed to its lower reactivity and the higher effectiveness of GSTA1-1 in stabilizing the active intermediate via H-bonds based on docking simulations.

15.
Curr Opin Biotechnol ; 66: 236-245, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33007634

RESUMO

Immune cells can sense and respond to biophysical cues - from dynamic forces to spatial features - during their development, activation, differentiation and expansion. These biophysical signals regulate a variety of immune cell functions such as leukocyte extravasation, macrophage polarization, T cell selection and T cell activation. Recent studies have advanced our understanding on immune responses to biophysical cues and the underlying mechanisms of mechanotransduction, which provides rational basis for the design and development of immune-modulatory therapeutics. This review discusses the recent progress in mechanosensing and mechanotransduction of immune cells, particularly monocytes/macrophages and T lymphocytes, and features new biomaterial designs and biomedical devices that translate these findings into biomedical applications.


Assuntos
Materiais Biocompatíveis , Mecanotransdução Celular , Biofísica , Diferenciação Celular , Macrófagos
16.
Zhonghua Yi Xue Za Zhi ; 89(13): 872-5, 2009 Apr 07.
Artigo em Zh | MEDLINE | ID: mdl-19671284

RESUMO

OBJECTIVE: To evaluate the impact of highly active antiretroviral therapy (HAART) on the haemorrhage status, joint function, and physical ability of the patients of hemophilia combined with acquired immunodeficiency syndrome (AIDS). METHODS: Thirty-nine hemophilia A/AIDS patients, all male, aged (40+/-13), underwent HAART and followed up for 6 years from 2002 to 2008 to observe the yearly hospital visit time, bleeding time, transfusion times, amount of factor VIII transfusion, VIII: C level, physical ability, and joint function. Flow cytometry was used to count the CD4+ T cells, and bDNA assay was used to examine the HIV virus load. RESULTS: The average hospital visit time, bleeding time, transfusion time, and amount of factor VIII transfusion, hemoglobin, white blood cell count, and platelet count before HAART were not significantly different from those after treatment (all P>0.05); only one case showed moderate decrease in VIII: C level, and another one case showed slight decline in physical ability and joint function. The serum HIV RNA load decreased from (4.8+/-1.0) log copies/ml before HAART to (2.4+/-1.0) log copies/ml (P<0.05) and the CD4+ T cell count raised from 183+/-97/mm3 to 456+/-157/mm3 (P<0.05) after HAART. CONCLUSION: HAART has no obvious impact on the haemorrhage status, joint function, and physical ability in hemophilia A/AIDS patients, however, it is effective to inhibit HIV replication and raise CD4+ T cell number which indicates that HAART therapy is positive for immune recovery.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Hemofilia A/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Seguimentos , Hemofilia A/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
17.
ACS Infect Dis ; 5(5): 759-768, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-30525438

RESUMO

Hepatitis B virus (HBV) core protein is a small protein with 183 amino acid residues and assembles the pregenomic (pg) RNA and viral DNA polymerase to form nucleocapsids. During the last decades, several groups have reported HBV core protein allosteric modulators (CpAMs) with distinct chemical structures. CpAMs bind to the hydrophobic HAP pocket located at the dimer-dimer interface and induce allosteric conformational changes in the core protein subunits. While Type I CpAMs, heteroaryldihydropyrimidine (HAP) derivatives, misdirect core protein dimers to assemble noncapsid polymers, Type II CpAMs, represented by sulfamoylbenzamides, phenylpropenamides, and several other chemotypes, induce the assembly of empty capsids with global structural alterations and faster mobility in native agarose gel electrophoresis. Through high throughput screening of an Asinex small molecule library containing 19 920 compounds, we identified 8 structurally distinct CpAMs. While 7 of those compounds are typical Type II CpAMs, a novel benzamide derivative, designated as BA-53038B, induced the formation of morphologically "normal" empty capsids with slow electrophoresis mobility. Drug resistant profile analyses indicated that BA-53038B most likely bound to the HAP pocket but obviously modulated HBV capsid assembly in a distinct manner. BA-53038B and other CpAMs reported herein provide novel structure scaffolds for the development of core protein-targeted antiviral agents for the treatment of chronic hepatitis B.


Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Vírus da Hepatite B/efeitos dos fármacos , Nucleocapsídeo/antagonistas & inibidores , Montagem de Vírus/efeitos dos fármacos , Células Hep G2 , Vírus da Hepatite B/fisiologia , Humanos , Bibliotecas de Moléculas Pequenas , Replicação Viral/efeitos dos fármacos
18.
ACS Infect Dis ; 5(7): 1139-1149, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31060350

RESUMO

Stimulator of interferon genes (STING) is an integral ER-membrane protein that can be activated by 2'3'-cGAMP synthesized by cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) upon binding of double-stranded DNA. It activates interferon (IFN) and inflammatory cytokine responses to defend against infection by microorganisms. Pharmacologic activation of STING has been demonstrated to induce an antiviral state and boost antitumor immunity. We previously reported a cell-based high-throughput-screening assay that allowed for identification of small-molecule cGAS-STING-pathway agonists. We report herein a compound, 6-bromo-N-(naphthalen-1-yl)benzo[d][1,3]dioxole-5-carboxamide (BNBC), that induces a proinflammatory cytokine response in a human-STING-dependent manner. Specifically, we showed that BNBC induced type I and III IFN dominant cytokine responses in primary human fibroblasts and peripheral-blood mononuclear cells (PBMCs). BNBC also induced cytokine response in PBMC-derived myeloid dendritic cells and promoted their maturation, suggesting that STING-agonist treatment could potentially regulate the activation of CD4+ and CD8+ T lymphocytes. As anticipated, treatment of primary human fibroblast cells with BNBC induced an antiviral state that inhibited the infection of several kinds of flaviviruses. Taken together, our results indicate that BNBC is a human-STING agonist that not only induces innate antiviral immunity against a broad spectrum of viruses but may also stimulate the activation of adaptive immune responses, which is important for the treatment of chronic viral infections and tumors.


Assuntos
Antivirais/síntese química , Benzodioxóis/síntese química , Infecções por Flavivirus/imunologia , Interferons/metabolismo , Proteínas de Membrana/agonistas , Imunidade Adaptativa/efeitos dos fármacos , Antivirais/química , Antivirais/farmacologia , Benzodioxóis/química , Benzodioxóis/farmacologia , Células Cultivadas , Células Hep G2 , Ensaios de Triagem em Larga Escala , Humanos , Imunidade Inata/efeitos dos fármacos , Proteínas de Membrana/química , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade
19.
Antiviral Res ; 150: 112-122, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29253498

RESUMO

Targeting host functions essential for viral replication has been considered as a broad spectrum and resistance-refractory antiviral approach. However, only a few host functions have, thus far, been validated as broad-spectrum antiviral targets in vivo. ER α-glucosidases I and II have been demonstrated to be essential for the morphogenesis of many enveloped viruses, including members from four families of viruses causing hemorrhagic fever. In vivo antiviral efficacy of various iminosugar-based ER α-glucosidase inhibitors has been reported in animals infected with Dengue, Japanese encephalitis, Ebola, Marburg and influenza viruses. Herein, we established Huh7.5-derived cell lines with ER α-glucosidase I or II knockout using CRISPR/Cas9 and demonstrated that the replication of Dengue, Yellow fever and Zika viruses was reduced by only 1-2 logs in the knockout cell lines. The results clearly indicate that only a partial suppression of viral replication can possibly be achieved with a complete inhibition of ER-α-glucosidases I or II by their inhibitors. We therefore explore to improve the antiviral efficacy of a lead iminosugar IHVR-19029 through combination with another broad-spectrum antiviral agent, favipiravir (T-705). Indeed, combination of IHVR-19029 and T-705 synergistically inhibited the replication of Yellow fever and Ebola viruses in cultured cells. Moreover, in a mouse model of Ebola virus infection, combination of sub-optimal doses of IHVR-19029 and T-705 significantly increased the survival rate of infected animals. We have thus proved the concept of combinational therapeutic strategy for the treatment of viral hemorrhagic fevers with broad spectrum host- and viral- targeting antiviral agents.


Assuntos
Antivirais/farmacologia , Ebolavirus/efeitos dos fármacos , Inibidores de Glicosídeo Hidrolases/farmacologia , Doença pelo Vírus Ebola/virologia , Animais , Antivirais/farmacocinética , Linhagem Celular , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Inibidores de Glicosídeo Hidrolases/farmacocinética , Doença pelo Vírus Ebola/tratamento farmacológico , Doença pelo Vírus Ebola/metabolismo , Humanos , Camundongos , Replicação Viral/efeitos dos fármacos , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo
20.
Zhonghua Gan Zang Bing Za Zhi ; 15(10): 734-7, 2007 Oct.
Artigo em Zh | MEDLINE | ID: mdl-17963597

RESUMO

OBJECTIVE: To evaluate the clinical effect and side-effect of peg-interferon alfa-2a (PEG-IFN alfa-2a) and highly active antiretroviral therapy (HAART) for patients infected with hepatitis C virus (HCV) and co-infected with human immunodeficiency virus (HIV). METHODS: Twenty-two patients with HCV/HIV co-infection received highly active antiretroviral therapy initially; after their CD4 lymphocyte counts rose to over 0.20x10(9)/L, they were separated into two groups: one group with CD4 lymphocytes over 0.35x10(9)/L (high group) and one group with CD4 lymphocytes below 0.35x10(9)/L (low group). Both groups were given 180 microg of PEG-IFN alfa-2a every week intramuscularly. HCV RNA and HIV RNA loads, blood cell and CD4 lymphocyte counts, and liver functions were routinely examined. RESULTS: After 12, 24 and 48 weeks of PEG-IFN alfa-2a therapy, mean HCV RNA loads reduced 2.0650 log10 copies/ml (t=3.8733), 2.9146 log10 copies/ml (t=7.6741) and 2.4315 log10 copies/ml (t=5.8202) from the baseline at week 0 in the 13 patients in the high group, and reduced 1.1522 log10 copies/ml (t = 2.8937), 1.4189 log10 copies/ml (t=2.4422) and 1.1167 log10 (t=1.1261) in the 8 patients of the low group. However, there was no significant difference between the early viral response rate (EVR) and the end of treatment viral response rate (ETVR) of the two groups. In the high group, the white blood cell count was lower at 24 weeks than the base line (t=2.4700), and the blood platelet count was lower both at 24 and 48 weeks than the base line (t=2.3273 and t=3.6149). CONCLUSIONS: PEG-IFN alfa-2a can effectively reduce HCV RNA loads in patients with HCV-/HIV co-infection, and the inhibition rate in patients with higher CD4 lymphocyte counts is better. The EVR and ETVR of the two groups of patients show similar results after the treatment. PEG-IFN alfa-2a can reduce the white blood cell counts and the blood platelet counts in the peripheral blood.


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Terapia Antirretroviral de Alta Atividade , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Superinfecção/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/virologia , Adulto , Contagem de Linfócito CD4 , HIV-1 , Hepacivirus , Hepatite C/virologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , RNA Viral , Proteínas Recombinantes , Superinfecção/virologia , Carga Viral , Adulto Jovem
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