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1.
Mol Ther ; 31(9): 2651-2661, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37394797

RESUMO

Mutant Z alpha-1 antitrypsin (ATZ) accumulates in globules in the liver and is the prototype of proteotoxic hepatic disease. Therapeutic strategies aiming at clearance of polymeric ATZ are needed. Transient receptor potential mucolipin-1 (TRPML1) is a lysosomal Ca2+ channel that maintains lysosomal homeostasis. In this study, we show that by increasing lysosomal exocytosis, TRPML1 gene transfer or small-molecule-mediated activation of TRPML1 reduces hepatic ATZ globules and fibrosis in PiZ transgenic mice that express the human ATZ. ATZ globule clearance induced by TRPML1 occurred without increase in autophagy or nuclear translocation of TFEB. Our results show that targeting TRPML1 and lysosomal exocytosis is a novel approach for treatment of the liver disease due to ATZ and potentially other diseases due to proteotoxic liver storage.


Assuntos
Hepatopatias , Canais de Potencial de Receptor Transitório , alfa 1-Antitripsina , Animais , Humanos , Camundongos , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/metabolismo , Hepatopatias/metabolismo , Lisossomos/metabolismo , Camundongos Transgênicos , Canais de Potencial de Receptor Transitório/genética , Canais de Potencial de Receptor Transitório/metabolismo
2.
EMBO Mol Med ; 15(4): e17033, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36647689

RESUMO

Gyrate atrophy of choroid and retina (GACR) is a chorioretinal degeneration caused by pathogenic variants in the gene encoding ornithine aminotransferase (OAT), an enzyme mainly expressed in liver. Affected patients have increased ornithine concentrations in blood and other body fluids and develop progressive constriction of vision fields leading to blindness. Current therapies are unsatisfactory and better treatments are highly needed. In two mouse models of OAT deficiency that recapitulates biochemical and retinal changes of GACR, we investigated the efficacy of an intravenously injected serotype 8 adeno-associated (AAV8) vector expressing OAT under the control of a hepatocyte-specific promoter. Following injections, OAT-deficient mice showed reductions of ornithine concentrations in blood and eye cups compared with control mice injected with a vector expressing green fluorescent protein. AAV-injected mice showed improved electroretinogram response and partial restoration of retinal structure up to one-year post-injection. In summary, hepatic OAT expression by AAV8 vector was effective at correction of hyperornithinemia and improved function and structure of the retina. In conclusion, this study provides proof-of-concept of efficacy of liver-directed AAV-mediated gene therapy of GACR.


Assuntos
Atrofia Girata , Degeneração Retiniana , Animais , Camundongos , Atrofia Girata/genética , Atrofia Girata/patologia , Ornitina-Oxo-Ácido Transaminase/genética , Ornitina-Oxo-Ácido Transaminase/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Ornitina/genética , Ornitina/metabolismo , Terapia Genética , Fígado/patologia
3.
Sci Total Environ ; 750: 141252, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33182174

RESUMO

Anthropogenic activities are seriously endangering the conservation of biodiversity worldwide, calling for urgent actions to mitigate their impact on ecosystems. We applied machine learning techniques to predict the response of freshwater ecosystems to multiple anthropogenic pressures, with the goal of informing the definition of water policy targets and management measures to recover and protect aquatic biodiversity. Random Forest and Gradient Boosted Regression Trees algorithms were used for the modelling of the biological indices of macroinvertebrates and diatoms in the Tagus river basin (Spain). Among the anthropogenic stressors considered as explanatory variables, the categories of land cover in the upstream catchment area and the nutrient concentrations showed the highest impact on biological communities. The model was then used to predict the biological response to different nutrient concentrations in river water, with the goal of exploring the effect of different regulatory thresholds on the ecosystem status. Specifically, we considered the maximum nutrient concentrations set by the Spanish legislation, as well as by the legislation of other European Union Member States. According to our model, the current nutrient thresholds in Spain ensure values of biological indices consistent with the good ecological status in only about 60% of the total number of water bodies. By applying more restrictive nutrient concentrations, the number of water bodies with biological indices in good status could increase by almost 40%. Moreover, coupling more restrictive nutrient thresholds with measures that improve the riparian habitat yields up to 85% of water bodies with biological indices in good status, thus proving to be a key approach to restore the status of the ecosystem.


Assuntos
Ecossistema , Rios , Monitoramento Ambiental , Aprendizado de Máquina , Espanha , Água
4.
Sci Total Environ ; 739: 139891, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32540657

RESUMO

Freshwater ecosystems and water uses may be jeopardized by the degradation of water quality. The Water Framework Directive of the European Union (EU) sets environmental objectives for water bodies but foresees the establishment of exemptions under some circumstances. The criteria used to justify these exemptions, however, are not fully developed, leaving their application open to some arbitrariness. Our study explores the relations between the magnitude of pressures affecting continental surface water bodies and the declared exemptions on the permitted concentration of nitrogen. It identifies different approaches to declare exemptions to nitrogen environmental objectives across six EU Member States and discusses the underlying criteria. A better understanding of the pressures-impact-measures/exemptions relation helps compare water policy decisions across different regions subject to the same legal obligations and set priorities for mitigation measures.

5.
Environ Manage ; 64(6): 721-735, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31705204

RESUMO

The alteration of natural flows due to water withdrawals and the presence of hydraulic infrastructure poses significant threats to the integrity of riverine ecosystems. The establishment of environmental flows (EF) has been conceived as a water management tool to mitigate the impact of in-stream flows alteration. To date, a large body of literature has focused on methods to define EF, but less attention has been paid to documenting and assessing their actual implementation on the ground. This article provides a framework to describe and assess the process of design, application, and monitoring of EF at a river basin level. The framework is applied to Spain, where significant efforts have been made during the past decade to define and implement EF across the country. The goal of the paper is to identify strengths and opportunities for improving the implementation of EF at country level. The Spanish legislation establishes that EF should contribute to the achievement of the good ecological status of surface water bodies as required by the European Union Water Framework Directive. Several pitfalls in the design, application, and monitoring of this important river management measure constrain the ability of the existing EF to deliver that fundamental outcome.


Assuntos
Ecossistema , Monitoramento Ambiental , União Europeia , Rios , Espanha
6.
J Cell Physiol ; 234(9): 15708-15716, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30697729

RESUMO

Peptidyl-prolyl cis-trans isomerase, NIMA-interacting 1 (PIN1) is a peptidyl-prolyl isomerase that binds phospho-Ser/Thr-Pro motifs in proteins and catalyzes the cis-trans isomerization of proline peptide bonds. PIN1 is overexpressed in several cancers including high-grade serous ovarian cancer. Since few therapies are effective against this cancer, PIN1 could be a therapeutic target but effective PIN1 inhibitors are lacking. To identify molecules with in vivo inhibitory effects on PIN1, we used consensus docking to model existing PIN1-ligand X-ray structures and to screen a chemical database for candidate inhibitors. Ten molecules were selected and tested in cellular assays, leading to the identification of VS10 that bound and inhibited PIN1. VS10 treatment reduced the viability of ovarian cancer cell lines by inducing proteasomal PIN1 degradation, without effects on PIN1 transcription, and also reduced the levels of downstream targets ß-catenin, cyclin D1, and pSer473-Akt. VS10 is a selective PIN1 inhibitor that may offer new opportunities for treating PIN1-overexpressing tumors.

7.
Chemosphere ; 209: 748-757, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29960942

RESUMO

The joint impact of the glyphosate-based commercial formulation Roundup Max® and the invasive mussel Limnoperna fortunei on phytoplankton and water quality was assessed in Salto Grande reservoir, a scenario were both stressors coexist. We performed an in situ mesocosm approach, through a 7-day experiment using 400-L enclosures. The following treatments were applied by triplicate: addition of 250 mussels (M); addition of 5 mg L-1 of active ingredient (a.i.) in Roundup Max® (R); addition of 250 mussels and 5 mg L-1 of a.i. in Roundup Max® (MR), and controls, without any addition (C). R showed higher total phosphorus (TP) and ammonium nitrogen (NNH4+) concentrations due to the herbicide input, and a significant increase in algal abundance, biovolume and chlorophyll a levels (Chl-a). In M mussels grazed on phytoplankton, which resulted in subsequent phosphates (SRP) release. A decrease in species diversity was observed in R and M with respect to C. In MR, there were higher TP and NNH4+ concentrations, a decrease in biovolume, an antagonistic effect on Chl-a and a synergistic effect on phytoplankton abundance. Species diversity and evenness showed a significant decrease due to the explosive growth of a small and opportunistic Chlorophyta, Spermatozopsis exsultans. The dominance of this species may be due to negative selectivity for S. exsultans and/or release of potential competitors by L. fortunei, and to the input of nutrients by Roundup Max® and/or removal of competitors by its toxicity.


Assuntos
Bivalves/química , Água Doce/microbiologia , Praguicidas/efeitos adversos , Fitoplâncton/microbiologia , Animais , Argentina , Poluentes Químicos da Água/análise
8.
J Control Release ; 281: 1-10, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29746956

RESUMO

Pin1, a prolyl isomerase that sustains tumor progression, is overexpressed in different types of malignancies. Functional inactivation of Pin1 restrains tumor growth and leaves normal cells unaffected making it an ideal pharmaceutical target. Although many studies on Pin1 have focused on malignancies that are influenced by sex hormones, studies in ovarian cancer have lagged behind. Here, we show that Pin1 is an important therapeutic target in high-grade serous epithelial ovarian cancer. Knock down of Pin1 in ovarian cancer cell lines induces apoptosis and restrains tumor growth in a syngeneic mouse model. Since specific and non-covalent Pin1 inhibitors are still limited, the first liposomal formulation of a Pin1 inhibitor was designed. The drug was efficiently encapsulated in modified cyclodextrins and remotely loaded into pegylated liposomes. This liposomal formulation accumulates preferentially in the tumor and has a desirable pharmacokinetic profile. The liposomal inhibitor was able to alter Pin1 cancer driving-pathways trough the induction of proteasome-dependent degradation of Pin1 and was found to be effective in curbing ovarian tumor growth in vivo.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Epitelial do Ovário/tratamento farmacológico , Ciclodextrinas/administração & dosagem , Indóis/administração & dosagem , Peptidilprolil Isomerase de Interação com NIMA/antagonistas & inibidores , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Carcinoma Epitelial do Ovário/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclodextrinas/farmacologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Feminino , Regulação da Expressão Gênica , Xenoenxertos , Humanos , Indóis/farmacologia , Lipossomos , Camundongos , Camundongos Nus , Peptidilprolil Isomerase de Interação com NIMA/genética , Peptidilprolil Isomerase de Interação com NIMA/metabolismo
9.
Molecules ; 23(4)2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29597300

RESUMO

Despite the advances in anticancer therapies, their effectiveness for many human tumors is still far from being optimal. Significant improvements in treatment efficacy can come from the enhancement of drug specificity. This goal may be achieved by combining the use of therapeutic molecules with tumor specific effects and delivery carriers with tumor targeting ability. In this regard, nucleic acid-based drug (NABD) and particularly small interfering RNAs (siRNAs), are attractive molecules due to the possibility to be engineered to target specific tumor genes. On the other hand, polymeric-based delivery systems are emerging as versatile carriers to generate tumor-targeted delivery systems. Here we will focus on the most recent findings in the selection of siRNA/polymeric targeted delivery systems for hepatocellular carcinoma (HCC), a human tumor for which currently available therapeutic approaches are poorly effective. In addition, we will discuss the most attracting and, in our opinion, promising siRNA-polymer combinations for HCC in relation to the biological features of HCC tissue. Attention will be also put on the mathematical description of the mechanisms ruling siRNA-carrier delivery, this being an important aspect to improve effectiveness reducing the experimental work.


Assuntos
Carcinoma Hepatocelular , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Hepáticas , Modelos Biológicos , Polímeros , RNA Interferente Pequeno , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Modelos Químicos , Polímeros/química , Polímeros/uso terapêutico , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico
10.
J Med Chem ; 61(3): 1340-1354, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29309142

RESUMO

Monoacylglycerol lipase (MAGL) is a serine hydrolase that plays an important role in the degradation of the endocannabinoid neurotransmitter 2-arachidonoylglycerol, which is implicated in many physiological processes. Beyond the possible utilization of MAGL inhibitors as anti-inflammatory, antinociceptive, and anticancer agents, their application has encountered obstacles due to the unwanted effects caused by the irreversible inhibition of this enzyme. The possible application of reversible MAGL inhibitors has only recently been explored, mainly due to the deficiency of known compounds possessing efficient reversible inhibitory activities. In this work, we report a new series of reversible MAGL inhibitors. Among them, compound 26 showed to be a potent MAGL inhibitor (IC50 = 0.51 µM, Ki = 412 nM) with a good selectivity versus fatty acid amide hydrolase (FAAH), α/ß-hydrolase domain-containing 6 (ABHD6), and 12 (ABHD12). Interestingly, this compound also possesses antiproliferative activities against two different cancer cell lines and relieves the neuropathic hypersensitivity induced in vivo by oxaliplatin.


Assuntos
Descoberta de Drogas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Pirazóis/química , Pirazóis/farmacologia , Analgésicos/química , Analgésicos/metabolismo , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/uso terapêutico , Masculino , Camundongos , Simulação de Acoplamento Molecular , Monoacilglicerol Lipases/química , Monoacilglicerol Lipases/metabolismo , Neuralgia/tratamento farmacológico , Conformação Proteica , Pirazóis/metabolismo , Pirazóis/uso terapêutico , Especificidade por Substrato
11.
Front Pharmacol ; 9: 1477, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30723410

RESUMO

PIN1 is a member of a family of peptidylprolyl isomerases that bind phosphoproteins and catalyze the rapid cis-trans isomerization of proline peptidyl bonds, resulting in an alteration of protein structure, function, and stability. PIN1 is overexpressed in human cancers, suggesting it promotes tumorigenesis, but depending on the cellular context, it also acts as a tumor suppressor. Here, we review the role of PIN1 in cancer and the regulation of PIN1 expression, and catalog the single nucleotide polymorphisms, and mutations in PIN1 gene associated with cancer. In addition, we provide a 3D model of the protein to localize the mutated residues.

13.
Expert Opin Drug Deliv ; 14(6): 797-810, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28266887

RESUMO

INTRODUCTION: hepatocellular carcinoma (hcc) is the predominant form of primary liver cancer and the second leading cause of cancer-associated mortality worldwide. available therapies for hcc have limited efficacy due to often late diagnosis and the general resistance of hcc to anti-cancer agents; therefore, the development of novel therapeutics is urgently required. small-interfering rna (sirna) molecules are short, double-stranded rnas that specifically recognize and bind the mrna of a target gene to inhibit gene expression. despite the great therapeutic potential of sirnas towards many human tumors including hcc, their use is limited by suboptimal delivery. Areas covered: In this review, we outline the current data regarding the therapeutic potential of siRNAs in HCC and describe the development of effective siRNA delivery systems. We detail the key problems associated with siRNA delivery and discuss the possible solutions. Finally, we provide examples of the various siRNA delivery strategies that have been employed in animal models of HCC and in human patients enrolled in clinical trials. Expert opinion: Despite the existing difficulties in siRNA delivery for HCC, the increasing scientific attention and breakthrough studies in this field is facilitating the design of novel and efficient technical solutions that may soon find practical applications.


Assuntos
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , RNA Interferente Pequeno/administração & dosagem , Animais , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/genética , Linhagem Celular , Humanos , Neoplasias Hepáticas/genética
14.
J Environ Manage ; 195(Pt 1): 46-55, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27836564

RESUMO

The uncertainty associated with the definition of strategies for climate change adaptation poses a challenge that cannot be faced by science alone. We present a participatory experience where, instead of having science defining solutions and eliciting stakeholders' feedback, local actors actually drove the process. While principles and methods of the approach are easily adaptable to different local contexts, this paper shows the contribution of participatory dynamics to the design of adaptation measures in the biodiversity-rich socio-ecological region surrounding the Doñana wetlands (Southern Spain). During the process, stakeholders and scientists collaboratively designed a common scenario for the future in which to define and assess a portfolio of potential adaptation measures, and found a safe, informal space for open dialogue and information exchange. Through this dialogue, points of connection among local actors emerged around the need for more integrated, transparent design of adaptation measures; for strengthening local capacity; and for strategies to diversify economic activities in order to increase the resilience of the region.


Assuntos
Mudança Climática , Ecossistema , Ecologia , Humanos , Espanha , Áreas Alagadas
15.
Philos Trans A Math Phys Eng Sci ; 371(2002): 20120415, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24080624

RESUMO

Hydroclimatic risks and adaptive capacity are not distributed evenly in large river basins of federal countries, where authority is divided across national and territorial governments. Transboundary river basins are a major test of federal systems of governance because key management roles exist at all levels. This paper examines the evolution and design of interstate water allocation institutions in semi-arid federal rivers prone to drought extremes, climatic variability and intensified competition for scarce water. We conceptualize, categorize and compare federal rivers as social-ecological systems to analyse the relationship between governance arrangements and hydroclimatic risks. A diagnostic approach is used to map over 300 federal rivers and classify the hydroclimatic risks of three semi-arid federal rivers with a long history of interstate allocation tensions: the Colorado River (USA/Mexico), Ebro River (Spain) and Murray-Darling River (Australia). Case studies review the evolution and design of water allocation institutions. Three institutional design trends have emerged: adoption of proportional interstate allocation rules; emergence of multi-layered river basin governance arrangements for planning, conflict resolution and joint monitoring; and new flexibility to adjust historic allocation patterns. Proportional allocation rules apportion water between states based on a share of available water, not a fixed volume or priority. Interstate allocation reform efforts in the Colorado and Murray-Darling rivers indicate that proportional allocation rules are prevalent for upstream states, while downstream states seek reliable deliveries of fixed volumes to increase water security. River basin governance arrangements establish new venues for multilayered planning, monitoring and conflict resolution to balance self governance by users and states with basin-wide coordination. Flexibility to adjust historic allocation agreements, without risk of defection or costly court action, also provides adaptive capacity to manage climatic variability and shifting values. Future research should develop evidence about pathways to adaptive capacity in different classes of federal rivers, while acknowledging limits to transferability and the need for context-sensitive design.

16.
Environ Manage ; 45(6): 1363-77, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20437178

RESUMO

Periodic assessment of progress toward established policy goals is crucial to understanding whether the applied efforts are effective. In Europe, the Water Framework Directive (WFD) adopted in year 2000 set ambitious environmental objectives to be achieved by the end of 2015 through the implementation of Integrated Water Resources Management (IWRM) principles. While at this stage it is premature to measure the impact of this Directive in terms of environmental outcomes, it is nonetheless important to develop indicators in order to monitor whether water management practices throughout Europe are aligning towards IWRM. This article presents the methodological development of the Water and Wetland Index, a comparative water policy assessment by environmental NGOs that was carried out in 2002-2003, and highlights the interest of repeating it in 2015, when the first WFD planning cycle will be completed.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Abastecimento de Água , Água , Europa (Continente)
17.
J Environ Manage ; 91(6): 1332-40, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20223583

RESUMO

Public participation is a key element of Integrated Water Resources Management and, in the European Union (EU), is a major challenge in the implementation of the Water Framework Directive (WFD), which was adopted in December 2000. When new legislation enters into force it is essential to set a baseline against which to measure the progress towards the established goals at significant milestones of its implementation. This paper presents an assessment of the quality of stakeholder participation at the beginning of the WFD implementation in twenty countries belonging to or with close institutional relationships with the EU. The evaluation was completed by environmental non-governmental organizations and it shows that already in 2003 there were positive examples of stakeholder participation in several countries but that, in general, the WFD implementation will require significant efforts to improve on participatory practices throughout Europe.


Assuntos
Conservação dos Recursos Naturais , Água , União Europeia
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