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BACKGROUND: Diabetes technology is a fundamental part of modern diabetes therapy. Its widespread usage is associated with an increasing amount of "diabetes technology waste." The aim of this study was to quantify this waste in a real-world situation in a specialized diabetes practice in Germany. METHODS: Eighty patients with diabetes and insulin treatment participated and collected all of their therapy-associated waste for three months. Their attitude toward sustainability of antidiabetic therapy, waste generation, and their own waste reduction/separation behavior was surveyed. RESULTS: In total, 23 707 pieces of therapy-associated waste were collected. They comprised 5362 test strips, 630 glucose sensors, 14 619 needles, 519 insulin cartridges, 599 pens, and 1463 pieces of aids for insulin pump therapy. Type and quantity of the collected waste depended on the type of diabetes and the respective therapy, ie, multiple daily injections, usage of glucose sensors, or pump therapy. Most participants (92%) were surprised by the amounts of waste and reported an increased awareness toward the resource consumption of their therapy (87%). The survey indicated an enhanced interest in waste separation (94%) and a demand for the reduction and recycling of devices/aids (93%). CONCLUSIONS: Our data revealed the amount and complexity of the waste generated by modern diabetes therapy. Extrapolating these data, it can be estimated that around 1.2 billion pieces of diabetes technology waste are generated in Germany per year. The major concern of the study participants was the limited number of recycling options. A clear demand for improved sustainability of the medical products was expressed.
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BACKGROUND: Recently, machine learning algorithms have identified preprocedural γ-glutamyl transferase (GGT) as a significant predictor of long-term mortality after coronary revascularization in the SYNTAX (Synergy Between PCI [Percutaneous Coronary Intervention] With Taxus and Cardiac Surgery) trial. The aim of the present study is to investigate the impact of preprocedural GGT on 10-year all-cause mortality in patients with complex coronary artery disease after revascularization. METHODS AND RESULTS: The SYNTAX trial was a randomized trial comparing PCI with coronary artery bypass grafting in 1800 patients with complex coronary artery disease. The present report is a post hoc subanalysis of the SYNTAXES (Synergy Between PCI With Taxus and Cardiac Surgery Extended Survival) trial, an investigator-driven extended 10-year follow-up of the SYNTAX trial. The association between preprocedural GGT and 10-year all-cause mortality was investigated. The mean values of GGT for men and women were 43.5 (SD, 48.5) and 36.4 (SD, 46.1) U/L, respectively. In multivariable Cox regression models adjusted by traditional risk factors, GGT was an independent predictor for all-cause death at 10-year follow-up, and each SD increase in log-GGT was associated with a 1.24-fold risk of all cause death at 10-year follow-up (95% CI, 1.10-1.40). According to previously reported sex-related GGT thresholds, patients with higher GGT level had a 1.74-fold risk of all-cause death at 10-year follow-up (95% CI, 1.32-2.29) compared with patients with lower GGT level. CONCLUSIONS: Preprocedural GGT is an independent predictor of 10-year mortality after coronary revascularization in patients with complex coronary artery disease. In patients with elevated GGT, strong secondary prevention may be required after revascularization and must be studied prospectively. REGISTRATION: URL: https://clinicaltrials.gov/study/NCT03417050.
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Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Masculino , Humanos , Feminino , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , gama-Glutamiltransferase , Resultado do Tratamento , Fatores de Risco , FígadoRESUMO
Mutations of the human leucine-rich repeat kinase 2 (LRRK2) have been associated with both, idiopathic and familial Parkinson's disease (PD). Most of these pathogenic mutations are located in the kinase domain (KD) or GTPase domain of LRRK2. In this study we describe a mechanism in which protein kinase activity can be modulated by reversible oxidation or reduction, involving a unique pair of adjacent cysteines, the "CC" motif. Among all human protein kinases, only LRRK2 contains this "CC" motif (C2024 and C2025) in the Activation Segment (AS) of the kinase domain. In an approach combining site-directed mutagenesis, biochemical analyses, cell-based assays, and Gaussian accelerated Molecular Dynamics (GaMD) simulations we could attribute a role for each of those cysteines. We employed reducing and oxidizing agents with potential clinical relevance to investigate effects on kinase activity and microtubule docking. We find that each cysteine gives a distinct contribution: the first cysteine, C2024, is essential for LRRK2 protein kinase activity, while the adjacent cysteine, C2025, contributes significantly to redox sensitivity. Implementing thiolates (R-S-) in GaMD simulations allowed us to analyse how each of the cysteines in the "CC" motif interacts with its surrounding residues depending on its oxidation state. From our studies we conclude that oxidizing agents can downregulate kinase activity of hyperactive LRRK2 PD mutations and may provide promising tools for therapeutic strategies.
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Leucine-rich repeat protein kinase 2 (LRRK2) is a multi-domain protein encompassing two of biology's most critical molecular switches, a kinase and a GTPase, and mutations in LRRK2 are key players in the pathogenesis of Parkinson's disease (PD). The availability of multiple structures (full-length and truncated) has opened doors to explore intra-domain cross-talk in LRRK2. A helix extending from the WD40 domain and stably docking onto the kinase domain is common in all available structures. This C-terminal (Ct) helix is a hub of phosphorylation and organelle-localization motifs and thus serves as a multi-functional protein : protein interaction module. To examine its intra-domain interactions, we have recombinantly expressed a stable Ct motif (residues 2480-2527) and used peptide arrays to identify specific binding sites. We have identified a potential interaction site between the Ct helix and a loop in the CORB domain (CORB loop) using a combination of Gaussian accelerated molecular dynamics simulations and peptide arrays. This Ct-Motif contains two auto-phosphorylation sites (T2483 and T2524), and T2524 is a 14-3-3 binding site. The Ct helix, CORB loop, and the CORB-kinase linker together form a part of a dynamic 'CAP' that regulates the N-lobe of the kinase domain. We hypothesize that in inactive, full-length LRRK2, the Ct-helix will also mediate interactions with the N-terminal armadillo, ankyrin, and LRR domains (NTDs) and that binding of Rab substrates, PD mutations, or kinase inhibitors will unleash the NTDs.
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Proteínas de Repetições Ricas em Leucina , Proteínas Serina-Treonina Quinases , Proteínas Serina-Treonina Quinases/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Domínios Proteicos , Mutação , Peptídeos/metabolismo , FosforilaçãoRESUMO
Water oxidation is a bottleneck reaction for the establishment of solar-to-fuel energy conversion systems. Earth-abundant metal-based polyoxometalates are promising heterogeneous water oxidation catalysts that can operate in a wide pH range. However, detailed structure-reactivity relationships are not yet comprehensively understood, hampering the design and synthesis of more effective polyoxometalate-based oxidation catalysts. Here we report the synthesis of an ordered, mixed-metal cobalt-iron Weakley archetype [CoII2(H2O)2FeIII2(CoIIW9O34)2]14- (Co2Fe2-WS), which unexpectedly highlights the strong influence of the central, coordinatively saturated metal ions on the catalytic water oxidation characteristics. The resulting species exhibits catalytic turnover frequencies which are up to 4× higher than those of the corresponding archetype tetracobalt-oxo species [CoII2(H2O)2CoII2(PW9O34)2]10- (Co4-WS). It is further striking that the system becomes catalytically inactive when one of the central positions is occupied by a WVI ion as demonstrated by [CoII2(H2O)2CoIIWVI(CoIIW9O34)2]12- (Co3W-WS). Importantly, this study demonstrates that coordinatively saturated metal ions in this central position, which at first glance appear insignificant, do not solely have a structural role but also impart a distinctive structural influence on the reactivity of the polyoxometalate. These results provide unique insights into the structure-reactivity relationships of polyoxometalates with improved catalytic performance characteristics.
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Hereditary retinal degeneration (RD) is often associated with excessive cGMP signalling in photoreceptors. Previous research has shown that inhibition of cGMP-dependent protein kinase G (PKG) can reduce photoreceptor loss in two different RD animal models. In this study, we identified a PKG inhibitor, the cGMP analogue CN238, which preserved photoreceptor viability and functionality in rd1 and rd10 mutant mice. Surprisingly, in explanted retinae, CN238 also protected retinal ganglion cells from axotomy-induced retrograde degeneration and preserved their functionality. Furthermore, kinase activity-dependent protein phosphorylation of the PKG target Kv1.6 was reduced in CN238-treated rd10 retinal explants. Ca2+-imaging on rd10 acute retinal explants revealed delayed retinal ganglion cell repolarization with CN238 treatment, suggesting a PKG-dependent modulation of Kv1-channels. Together, these results highlight the strong neuroprotective capacity of PKG inhibitors for both photoreceptors and retinal ganglion cells, illustrating their broad potential for the treatment of retinal diseases and possibly neurodegenerative diseases in general.
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Degeneração Retiniana , Camundongos , Animais , Degeneração Retiniana/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Células Fotorreceptoras/metabolismo , Retina/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BLRESUMO
Microtubule-Associated Serine/Threonine (MAST) kinases represent an evolutionary conserved branch of the AGC protein kinase superfamily in the kinome. Since the discovery of the founding member, MAST2, in 1993, three additional family members have been identified in mammals and found to be broadly expressed across various tissues, including the brain, heart, lung, liver, intestine and kidney. The study of MAST kinases is highly relevant for unraveling the molecular basis of a wide range of different human diseases, including breast and liver cancer, myeloma, inflammatory bowel disease, cystic fibrosis and various neuronal disorders. Despite several reports on potential substrates and binding partners of MAST kinases, the molecular mechanisms that would explain their involvement in human diseases remain rather obscure. This review will summarize data on the structure, biochemistry and cell and molecular biology of MAST kinases in the context of biomedical research as well as organismal model systems in order to provide a current profile of this field.
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BACKGROUND: The SYNTAX trial demonstrated negative impact of repeat revascularization (RR) on 5-year outcomes following PCI/CABG in patients with three-vessel(3VD) and/or left main coronary artery disease(LMCAD). We aimed to investigate the impact of RR within 5 years, on 10-year mortality in patients with 3VD and/or LMCAD after PCI/CABG. METHODS: The SYNTAXES study evaluated the vital status out to 10 years of patients with 3VD and/or LMCAD. Patients were stratified by RR within 5 years and randomized treatment. The association between RR within 5 years and 10-year mortality was assessed. RESULTS: A total of 330 out of 1800 patients (18.3%) underwent RR within 5 years. RR occurred more frequently after initial PCI than after initial CABG (25.9% vs. 13.7%, p < 0.001). Overall, 10-year mortality was comparable between patients undergoing RR and those not (28.2% vs. 26.1%, adjusted HR: 1.17, 95%CI 0.93-1.48, p = 0.187). In the PCI arm, RR was associated with a trend toward higher 10-year mortality (adjusted HR: 1.29, 95%CI 0.97-1.72, p = 0.075), while in the CABG arm, the trend was opposite (adjusted HR: 0.74, 95%CI 0.46-1.20, p = 0.219). Among patients requiring RR, those who underwent PCI as initial revascularization had a higher risk of 10-year mortality compared to initial CABG (33.5% vs. 17.6%, adjusted HR: 2.09, 95%CI 1.21-3.61, p = 0.008). CONCLUSION: In the SYNTAXES study, RR within 5 years had no impact on 10-year all-cause death in the population overall. Among patients requiring any repeat procedures, 10-year mortality was higher after initial treatment with PCI than after CABG. These exploratory findings should be investigated with larger populations in future studies. TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov ; SYNTAXES Unique identifier: NCT03417050. URL: https://www. CLINICALTRIALS: gov ; SYNTAX Unique identifier: NCT00114972.
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Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Humanos , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/métodos , Intervenção Coronária Percutânea/métodos , Resultado do Tratamento , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/cirurgiaRESUMO
LRRK2 is a multi-domain protein with three catalytically inert N-terminal domains (NtDs) and four C-terminal domains, including a kinase and a GTPase domain. LRRK2 mutations are linked to Parkinson's Disease. Recent structures of LRRK2RCKW and a full-length inactive LRRK2 (fl-LRRK2INACT) monomer revealed that the kinase domain drives LRRK2 activation. The LRR domain and also an ordered LRR- COR linker, wrap around the C-lobe of the kinase domain and sterically block the substrate binding surface in fl-LRRK2INACT. Here we focus on the crosstalk between domains. Our biochemical studies of GTPase and kinase activities of fl-LRRK2 and LRRK2RCKW reveal how mutations influence this crosstalk differently depending on the domain borders investigated. Furthermore, we demonstrate that removing the NtDs leads to altered intramolecular regulation. To further investigate the crosstalk, we used Hydrogen-Deuterium exchange Mass Spectrometry (HDX-MS) to characterize the conformation of LRRK2RCKW and Gaussian Accelerated Molecular Dynamics (GaMD) to create dynamic portraits of fl-LRRK2 and LRRK2RCKW. These models allowed us to investigate the dynamic changes in wild type and mutant LRRK2s. Our data show that the a3ROC helix, the Switch II motif in the ROC domain, and the LRR-ROC linker play crucial roles in mediating local and global conformational changes. We demonstrate how these regions are affected by other domains in fl-LRRK2 and LRRK2RCKW and show how unleashing of the NtDs as well as PD mutations lead to changes in conformation and dynamics of the ROC and kinase domains which ultimately impact kinase and GTPase activities. These allosteric sites are potential therapeutic targets.
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Although Fischer's extraordinary career came to focus mostly on the protein phosphatases, after his co-discovery of Phosphorylase Kinase with Ed Krebs he was clearly intrigued not only by cAMP-dependent protein kinase (PKA), but also by the heat-stable, high-affinity protein kinase inhibitor (PKI). PKI is an intrinsically disordered protein that contains at its N-terminus a pseudo-substrate motif that binds synergistically and with high-affinity to the PKA catalytic (C) subunit. The sequencing and characterization of this inhibitor peptide (IP20) were validated by the structure of the PKA C-subunit solved first as a binary complex with IP20 and then as a ternary complex with ATP and two magnesium ions. A second motif, nuclear export signal (NES), was later discovered in PKI. Both motifs correspond to amphipathic helices that convey high-affinity binding. The dynamic features of full-length PKI, recently captured by NMR, confirmed that the IP20 motif becomes dynamically and sequentially ordered only in the presence of the C-subunit. The type I PKA regulatory (R) subunits also contain a pseudo-substrate ATPMg2-dependent high-affinity inhibitor sequence. PKI and PKA, especially the Cß subunit, are highly expressed in the brain, and PKI expression is also cell cycle-dependent. In addition, PKI is now linked to several cancers. The full biological importance of PKI and PKA signaling in the brain, and their importance in cancer thus remains to be elucidated.
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Proteínas Quinases Dependentes de AMP Cíclico , Inibidores de Proteínas Quinases , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/química , Peptídeos/químicaRESUMO
Mutations in LRRK2, a large multi-domain protein kinase, create risk factors for Parkinson's Disease (PD). LRRK2 has seven well-folded domains that include three N-terminal scaffold domains (NtDs) and four C-terminal domains (CtDs). In full-length inactive LRRK2 there is an additional well-folded motif, the LRR-ROC Linker, that lies between the NtDs and the CtDs. This motif, which is stabilized by hydrophobic residues in the LRR and ROC/COR-A domains, is anchored to the C-Lobe of the kinase domain. The LRR-ROC Linker becomes disordered when the NtDs are unleashed from the CtDs following activation by Rab29 or by various PD mutations. A key residue within the LRR-ROC Linker, W1295, sterically blocks access of substrate proteins. The W1295A mutant blocks cis-autophosphorylation of S1292 and reduces phosphorylation of heterologous Rab substrates. GaMD simulations show that the LRR-Linker motif, P + 1 loop and the inhibitory helix in the DYGψ motif are very stable. Finally, in full-length inactive LRRK2 ATP is bound to the kinase domain and GDP:Mg to the GTPase/ROC domain. The fundamentally different mechanisms for binding nucleotide (G-Loop vs P-Loop) are captured by these GaMD simulations. In this model, where ATP binds with low affinity (µM range) to N-Lobe capping residues, the known auto-phosphorylation sites are located in the space that is sampled by the flexible phosphates thus providing a potential mechanism for cis-autophosphorylation.
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Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Doença de Parkinson , Trifosfato de Adenosina/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Mutação , Fosforilação , Humanos , Doença de Parkinson/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismoRESUMO
BACKGROUND: The long-term prognostic impact of a composite of periprocedural major adverse events (PMAE) following revascularisation for patients with complex coronary artery disease (CAD) has not yet been established. AIMS: This study aimed to assess the impact on 10-year mortality of non-fatal PMAE following percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Other objectives were to evaluate 1) whether PMAE affect mortality predicted by the SYNTAX score II 2020 (SSII-2020) and 2) whether optimal medical therapy (OMT) positively affects the prognosis of patients with non-fatal PMAE. METHODS: The association between 10-year mortality and non-fatal PMAE occurring within 30 days of PCI or CABG in patients with three-vessel disease and/or left main disease enrolled in the SYNTAXES study was investigated. RESULTS: The main findings are that non-fatal PMAE occurred less frequently following PCI than CABG (11.2% vs 28.2%; p<0.001) and that non-fatal PMAE were an independent predictor of all-cause mortality in the first year post-procedure, but not at 5 or 10 years, in both treatment modalities. PMAE substantially alter the individual predictions of 10-year mortality by the SSII-2020. In patients with non-fatal PMAE, OMT may provide survival benefits during the first year post-procedure as well as in the long term. CONCLUSIONS: In patients with complex CAD, non-fatal PMAE were more common following CABG than PCI, but their prognostic impact was similar, being significant in the first year and then diminishing out to 10 years. Patients with non-fatal PMAE may therefore require more careful follow-up and additional preventive treatment in the first year post-procedure.
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Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Stents Farmacológicos/efeitos adversos , Doença da Artéria Coronariana/cirurgia , Ponte de Artéria Coronária/métodos , Prognóstico , Resultado do TratamentoRESUMO
The sensory ion channel transient receptor potential vanilloid 1 (TRPV1) is mainly expressed in small to medium sized dorsal root ganglion neurons, which are involved in the transfer of acute noxious thermal and chemical stimuli. The Ankyrin-rich membrane spanning protein (ARMS) interaction with TRPV1 is modulated by protein kinase A (PKA) mediating sensitization. Here, we hypothesize that PKA phosphorylation sites of ARMS are crucial for the modulation of TRPV1 function, and that the phosphorylation of ARMS is facilitated by the A-kinase anchoring protein 79 (AKAP79). We used transfected HEK293 cells, immunoprecipitation, calcium flux, and patch clamp experiments to investigate potential PKA phosphorylation sites in ARMS and in ARMS-related peptides. Additionally, experiments were done to discriminate between PKA and protein kinase D (PKD) phosphorylation. We found different interaction ratios for TRPV1 and ARMS mutants lacking PKA phosphorylation sites. The degree of TRPV1 sensitization by ARMS mutants is independent on PKA phosphorylation. AKAP79 was also involved in the TRPV1/ARMS/PKA signaling complex. These data show that ARMS is a PKA substrate via AKAP79 in the TRPV1 signaling complex and that all four proteins interact physically, regulating TRPV1 sensitization in transfected HEK293 cells. To assess the physiological and/or therapeutic significance of these findings, similar investigations need to be performed in native neurons and/or in vivo.
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Anquirinas , Proteínas de Membrana , Humanos , Anquirinas/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Células HEK293 , Proteínas de Membrana/metabolismo , Fosforilação , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismoRESUMO
BACKGROUND: Phosphodiesterase 3A (PDE3A) gain-of-function mutations cause hypertension with brachydactyly (HTNB) and lead to stroke. Increased peripheral vascular resistance, rather than salt retention, is responsible. It is surprising that the few patients with HTNB examined so far did not develop cardiac hypertrophy or heart failure. We hypothesized that, in the heart, PDE3A mutations could be protective. METHODS: We studied new patients. CRISPR-Cas9-engineered rat HTNB models were phenotyped by telemetric blood pressure measurements, echocardiography, microcomputed tomography, RNA-sequencing, and single nuclei RNA-sequencing. Human induced pluripotent stem cells carrying PDE3A mutations were established, differentiated to cardiomyocytes, and analyzed by Ca2+ imaging. We used Förster resonance energy transfer and biochemical assays. RESULTS: We identified a new PDE3A mutation in a family with HTNB. It maps to exon 13 encoding the enzyme's catalytic domain. All hitherto identified HTNB PDE3A mutations cluster in exon 4 encoding a region N-terminally from the catalytic domain of the enzyme. The mutations were recapitulated in rat models. Both exon 4 and 13 mutations led to aberrant phosphorylation, hyperactivity, and increased PDE3A enzyme self-assembly. The left ventricles of our patients with HTNB and the rat models were normal despite preexisting hypertension. A catecholamine challenge elicited cardiac hypertrophy in HTNB rats only to the level of wild-type rats and improved the contractility of the mutant hearts, compared with wild-type rats. The ß-adrenergic system, phosphodiesterase activity, and cAMP levels in the mutant hearts resembled wild-type hearts, whereas phospholamban phosphorylation was decreased in the mutants. In our induced pluripotent stem cell cardiomyocyte models, the PDE3A mutations caused adaptive changes of Ca2+ cycling. RNA-sequencing and single nuclei RNA-sequencing identified differences in mRNA expression between wild-type and mutants, affecting, among others, metabolism and protein folding. CONCLUSIONS: Although in vascular smooth muscle, PDE3A mutations cause hypertension, they confer protection against hypertension-induced cardiac damage in hearts. Nonselective PDE3A inhibition is a final, short-term option in heart failure treatment to increase cardiac cAMP and improve contractility. Our data argue that mimicking the effect of PDE3A mutations in the heart rather than nonselective PDE3 inhibition is cardioprotective in the long term. Our findings could facilitate the search for new treatments to prevent hypertension-induced cardiac damage.
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Insuficiência Cardíaca , Hipertensão , Células-Tronco Pluripotentes Induzidas , Humanos , Ratos , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Microtomografia por Raio-X , Células-Tronco Pluripotentes Induzidas/metabolismo , Hipertensão/complicações , Hipertensão/genética , Miócitos Cardíacos/metabolismo , Cardiomegalia , RNARESUMO
The Hedgehog (Hh) cascade is central to development, tissue homeostasis and cancer. A pivotal step in Hh signal transduction is the activation of glioma-associated (GLI) transcription factors by the atypical G protein-coupled receptor (GPCR) SMOOTHENED (SMO). How SMO activates GLI remains unclear. Here we show that SMO uses a decoy substrate sequence to physically block the active site of the cAMP-dependent protein kinase (PKA) catalytic subunit (PKA-C) and extinguish its enzymatic activity. As a result, GLI is released from phosphorylation-induced inhibition. Using a combination of in vitro, cellular and organismal models, we demonstrate that interfering with SMO-PKA pseudosubstrate interactions prevents Hh signal transduction. The mechanism uncovered echoes one used by the Wnt cascade, revealing an unexpected similarity in how these two essential developmental and cancer pathways signal intracellularly. More broadly, our findings define a mode of GPCR-PKA communication that may be harnessed by a range of membrane receptors and kinases.
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Antineoplásicos , Proteínas de Drosophila , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas Hedgehog/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/fisiologia , Receptor Smoothened/genética , Receptor Smoothened/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Cyclic GMP-dependent protein kinases (PKGs) are key mediators of the nitric oxide/cyclic guanosine monophosphate (cGMP) signaling pathway that regulates biological functions as diverse as smooth muscle contraction, cardiac function, and axon guidance. Understanding how cGMP differentially triggers mammalian PKG isoforms could lead to new therapeutics that inhibit or activate PKGs, complementing drugs that target nitric oxide synthases and cyclic nucleotide phosphodiesterases in this signaling axis. Alternate splicing of PRKG1 transcripts confers distinct leucine zippers, linkers, and auto-inhibitory (AI) pseudo-substrate sequences to PKG Iα and Iß that result in isoform-specific activation properties, but the mechanism of enzyme auto-inhibition and its alleviation by cGMP is not well understood. Here, we present a crystal structure of PKG Iß in which the AI sequence and the cyclic nucleotide-binding (CNB) domains are bound to the catalytic domain, providing a snapshot of the auto-inhibited state. Specific contacts between the PKG Iß AI sequence and the enzyme active site help explain isoform-specific activation constants and the effects of phosphorylation in the linker. We also present a crystal structure of a PKG I CNB domain with an activating mutation linked to Thoracic Aortic Aneurysms and Dissections. Similarity of this structure to wildtype cGMP-bound domains and differences with the auto-inhibited enzyme provide a mechanistic basis for constitutive activation. We show that PKG Iß auto-inhibition is mediated by contacts within each monomer of the native full-length dimeric protein, and using the available structural and biochemical data we develop a model for the regulation and cooperative activation of PKGs.
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Proteína Quinase Dependente de GMP Cíclico Tipo I , Óxido Nítrico , Animais , GMP Cíclico , Mamíferos , Fosforilação , Isoformas de ProteínasRESUMO
BACKGROUND: Clinical and anatomical characteristics are often considered key factors in deciding between percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) in patients with complex coronary artery disease (CAD) such as left-main CAD or 3-vessel disease. However, little is known about the interaction between self-reported preprocedural physical/mental health and clinical outcomes after revascularization. METHODS: This subgroup analysis of the SYNTAXES trial (SYNTAX Extended Survival), which is the extended follow-up of the randomized SYNTAX trial (Synergy Between PCI With Taxus and Cardiac Surgery) comparing PCI with CABG in patients with left-main CAD or 3-vessel disease, stratified patients by terciles of Physical (PCS) or Mental Component Summary (MCS) scores derived from the preprocedural 36-Item Short Form Health Survey, with higher PCS and MCS scores representing better physical and mental health, respectively. The primary end point was all-cause death at 10 years. RESULTS: A total of 1656 patients with preprocedural 36-Item Short Form Health Survey data were included in the present study. Both higher PCS and MCS were independently associated with lower 10-year mortality (10-point increase in PCS adjusted hazard ratio, 0.84 [95% CI, 0.73-0.97]; P=0.021; in MCS adjusted hazard ratio, 0.85 [95% CI, 0.76-0.95]; P=0.005). A significant survival benefit with CABG over PCI was observed in the highest PCS (>45.5) and MCS (>52.3) terciles with significant treatment-by-subgroup interactions (PCS Pinteraction=0.033, MCS Pinteraction=0.015). In patients with both high PCS (>45.5) and MCS (>52.3), 10-year mortality was significantly higher with PCI compared with CABG (30.5% versus 12.2%; hazard ratio, 2.87 [95% CI, 1.55-5.30]; P=0.001), whereas among those with low PCS (≤45.5) or low MCS (≤52.3), there were no significant differences in 10-year mortality between PCI and CABG, resulting in a significant treatment-by-subgroup interaction (Pinteraction=0.002). CONCLUSIONS: Among patients with left-main CAD or 3-vessel disease, patient-reported preprocedural physical and mental health status was strongly associated with long-term mortality and modified the relative treatment effects of PCI versus CABG. Patients with the best physical and mental health had better 10-year survival with CABG compared with PCI. Assessment of self-reported physical and mental health is important when selecting the optimal revascularization strategy. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; SYNTAXES Unique identifier: NCT03417050. URL: https://www. CLINICALTRIALS: gov; SYNTAX Unique identifier: NCT00114972.
Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Humanos , Doença da Artéria Coronariana/cirurgia , Saúde Mental , Medidas de Resultados Relatados pelo Paciente , Fatores de Risco , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: We sought to investigate whether long-term clinical outcomes differ following percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) in patients with three-vessel disease (3VD) and lesions in the proximal left anterior descending artery (P-LAD). METHODS: This post-hoc analysis of the Synergy between PCI with Taxus and Cardiac Surgery (SYNTAX) Extended Survival study included patients with 3VD who were classified according to the presence or absence of lesions located in the P-LAD. Ten-year all-cause death and 5-year major adverse cardiac or cerebrovascular events (MACCE) were assessed. RESULTS: Among 1088 patients with 3VD, 559 (51.4%) had involvement of P-LAD and their 10-year mortality was numerically higher following PCI versus CABG (28.9% vs 21.9%; HR: 1.39, 95% CI 0.99 to 1.95). Although patients without P-LAD lesions had significantly higher 10-year mortality following PCI compared with CABG, there was no evidence of a treatment-by-subgroup interaction (28.8% vs 20.2%; HR: 1.47, 95% CI 1.03 to 2.09, pinteraction=0.837). The incidence of MACCE at 5 years was significantly higher with PCI than CABG, irrespective of involvement of P-LAD (with P-LAD: HR: 1.86, 95% CI 1.36 to 2.55; without P-LAD: HR: 1.54, 95% CI 1.11 to 2.12; pinteraction=0.408). Individualised assessment using the SYNTAX Score II 2020 established that a quarter of patients with P-LAD lesions had significantly higher mortality with PCI than CABG, whereas in the remaining three-quarters CABG had similar mortality. CONCLUSIONS: Among patients with 3VD, the presence or absence of a P-LAD lesion was not associated with any treatment effect on long-term outcomes following PCI or CABG. TRIAL REGISTRATION NUMBER: SYNTAXES: NCT03417050; SYNTAX: NCT00114972.
Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Humanos , Artérias , Ponte de Artéria Coronária/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Intervenção Coronária Percutânea/efeitos adversos , Resultado do TratamentoRESUMO
Hydropower is a threat to freshwater fishes. Despite a recent boom in dam construction, few studies have assessed their impact on mega-diverse tropical rivers. Using a before-after study design, we investigated the early impacts of the Belo Monte hydroelectric complex, the third-largest hydropower project in the world, on fishes of the Xingu River, a major clear-water tributary of the lower Amazon. We explored impacts across different river sectors (upstream, reservoir, reduced flow sector, and downstream) and spatial scales (individual sectors vs. all sectors combined) using joint species distribution models and different facets of diversity (taxonomic, functional, and phylogenetic). After 5 years of the Belo Monte operation, species richness declined ~12% in lentic and ~16% in lotic environments. Changes in abundance were of less magnitude (<4%). Effects were particularly negative for species of the families Serrasalmidae (mainly pacus), Anostomidae (headstanders), Auchenipteridae, and Pimelodidae (catfishes), whereas no taxonomic group consistently increased in richness or abundance. The reservoir and downstream sectors were the most impacted, with declines of ~24-29% in fish species richness, overall reductions in fish body size and trophic level, and a change in average body shape. Richness and abundance also declined in the reduced river flow, and changes in size, shape, and position of fins were observed. Relatively minor changes were found in the upstream sector. Variation in functional and phylogenetic diversity following river impoundment was subtle; however, across sectors, we found a reduction in functional divergence, indicating a decline in the abundance of species located near the extremities of community functional space. This may be the first sign of an environmental filtering process reducing functional diversity in the region. Greater changes in flow and habitats are expected as hydropower operations ramp up, and continued monitoring is warranted to understand the full scope and magnitude of ecological impacts.