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1.
Cell ; 169(1): 24-34, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28340346

RESUMO

Interconnectivity and feedback control are hallmarks of biological systems. This includes communication between organelles, which allows them to function and adapt to changing cellular environments. While the specific mechanisms for all communications remain opaque, unraveling the wiring of organelle networks is critical to understand how biological systems are built and why they might collapse, as occurs in aging. A comprehensive understanding of all the routes involved in inter-organelle communication is still lacking, but important themes are beginning to emerge, primarily in budding yeast. These routes are reviewed here in the context of sub-system proteostasis and complex adaptive systems theory.


Assuntos
Organelas/fisiologia , Saccharomyces cerevisiae/citologia , Envelhecimento/fisiologia , Animais , Divisão Celular , Humanos , Proteínas/química , Saccharomyces cerevisiae/fisiologia , Transdução de Sinais
2.
Cell ; 166(1): 140-51, 2016 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-27264606

RESUMO

Caloric restriction (CR) extends the lifespan of flies, worms, and yeast by counteracting age-related oxidation of H2O2-scavenging peroxiredoxins (Prxs). Here, we show that increased dosage of the major cytosolic Prx in yeast, Tsa1, extends lifespan in an Hsp70 chaperone-dependent and CR-independent manner without increasing H2O2 scavenging or genome stability. We found that Tsa1 and Hsp70 physically interact and that hyperoxidation of Tsa1 by H2O2 is required for the recruitment of the Hsp70 chaperones and the Hsp104 disaggregase to misfolded and aggregated proteins during aging, but not heat stress. Tsa1 counteracted the accumulation of ubiquitinated aggregates during aging and the reduction of hyperoxidized Tsa1 by sulfiredoxin facilitated clearance of H2O2-generated aggregates. The data reveal a conceptually new role for H2O2 signaling in proteostasis and lifespan control and shed new light on the selective benefits endowed to eukaryotic peroxiredoxins by their reversible hyperoxidation.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Peróxido de Hidrogênio/metabolismo , Longevidade , Peroxidases/metabolismo , Dobramento de Proteína , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Animais , Restrição Calórica , Instabilidade Genômica , Proteínas de Choque Térmico/metabolismo , Humanos , Oxirredução , Agregados Proteicos , Saccharomyces cerevisiae/citologia , Transdução de Sinais
3.
Plant Cell ; 35(9): 3325-3344, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37401663

RESUMO

Stress granules (SGs) are highly conserved cytoplasmic condensates that assemble in response to stress and contribute to maintaining protein homeostasis. These membraneless organelles are dynamic, disassembling once the stress is no longer present. Persistence of SGs due to mutations or chronic stress has been often related to age-dependent protein-misfolding diseases in animals. Here, we find that the metacaspase MC1 is dynamically recruited into SGs upon proteotoxic stress in Arabidopsis (Arabidopsis thaliana). Two predicted disordered regions, the prodomain and the 360 loop, mediate MC1 recruitment to and release from SGs. Importantly, we show that MC1 has the capacity to clear toxic protein aggregates in vivo and in vitro, acting as a disaggregase. Finally, we demonstrate that overexpressing MC1 delays senescence and this phenotype is dependent on the presence of the 360 loop and an intact catalytic domain. Together, our data indicate that MC1 regulates senescence through its recruitment into SGs and this function could potentially be linked to its remarkable protein aggregate-clearing activity.


Assuntos
Arabidopsis , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Agregados Proteicos , Grânulos de Estresse , Grânulos Citoplasmáticos/metabolismo , Estresse Fisiológico
4.
Cell ; 140(2): 257-67, 2010 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-20141839

RESUMO

The paradigm sirtuin, Sir2p, of budding yeast is required for establishing cellular age asymmetry, which includes the retention of damaged and aggregated proteins in mother cells. By establishing the global genetic interaction network of SIR2 we identified the polarisome, the formin Bni1p, and myosin motor protein Myo2p as essential components of the machinery segregating protein aggregates during mitotic cytokinesis. Moreover, we found that daughter cells can clear themselves of damage by a polarisome- and tropomyosin-dependent polarized flow of aggregates into the mother cell compartment. The role of Sir2p in cytoskeletal functions and polarity is linked to the CCT chaperonin in sir2Delta cells being compromised in folding actin. We discuss the findings in view of recent models hypothesizing that polarity may have evolved to avoid clonal senescence by establishing an aging (soma-like) and rejuvenated (germ-like) lineage.


Assuntos
Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Actinas/metabolismo , Chaperoninas/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas dos Microfilamentos/metabolismo , Mitose , Organelas/metabolismo , Transporte Proteico , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Sirtuína 2/metabolismo
5.
PLoS Genet ; 18(11): e1010442, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36350833

RESUMO

Hsp90 constitutes one of the major chaperone machinery in the cell. The Hsp70 assists Hsp90 in its client maturation though the underlying basis of the Hsp70 role remains to be explored. In the present study, using S. cerevisiae strain expressing Ssa1 as sole Ssa Hsp70, we identified novel mutations in the nucleotide-binding domain of yeast Ssa1 Hsp70 (Ssa1-T175N and Ssa1-D158N) that adversely affect the maturation of Hsp90 clients v-Src and Ste11. The identified Ssa1 amino acids critical for Hsp90 function were also found to be conserved across species such as in E.coli DnaK and the constitutive Hsp70 isoform (HspA8) in humans. These mutations are distal to the C-terminus of Hsp70, that primarily mediates Hsp90 interaction through the bridge protein Sti1, and proximal to Ydj1 (Hsp40 co-chaperone of Hsp70 family) binding region. Intriguingly, we found that the bridge protein Sti1 is critical for cellular viability in cells expressing Ssa1-T175N (A1-T175N) or Ssa1-D158N (A1-D158N) as sole Ssa Hsp70. The growth defect was specific for sti1Δ, as deletion of none of the other Hsp90 co-chaperones showed lethality in A1-T175N or A1-D158N. Mass-spectrometry based whole proteome analysis of A1-T175N cells lacking Sti1 showed an altered abundance of various kinases and transcription factors suggesting compromised Hsp90 activity. Further proteomic analysis showed that pathways involved in signaling, signal transduction, and protein phosphorylation are markedly downregulated in the A1-T175N upon repressing Sti1 expression using doxycycline regulatable promoter. In contrast to Ssa1, the homologous mutations in Ssa4 (Ssa4-T175N/D158N), the stress inducible Hsp70 isoform, supported cell growth even in the absence of Sti1. Overall, our data suggest that Ydj1 competes with Hsp90 for binding to Hsp70, and thus regulates Hsp90 interaction with the nucleotide-binding domain of Hsp70. The study thus provides new insight into the Hsp70-mediated regulation of Hsp90 and broadens our understanding of the intricate complexities of the Hsp70-Hsp90 network.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteômica , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Chaperonas Moleculares/genética , Nucleotídeos/metabolismo , Ligação Proteica , Adenosina Trifosfatases/metabolismo , MAP Quinase Quinase Quinases/metabolismo
6.
Diabetologia ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668761

RESUMO

AIMS/HYPOTHESIS: Previous studies have shown that individuals with similar mean glucose levels (MG) or percentage of time in range (TIR) may have different HbA1c values. The aim of this study was to further elucidate how MG and TIR are associated with HbA1c. METHODS: Data from the randomised clinical GOLD trial (n=144) and the follow-up SILVER trial (n=98) of adults with type 1 diabetes followed for 2.5 years were analysed. A total of 596 paired HbA1c/continuous glucose monitoring measurements were included. Linear mixed-effects models were used to account for intra-individual correlations in repeated-measures data. RESULTS: In the GOLD trial, the mean age of the participants (± SD) was 44±13 years, 63 (44%) were female, and the mean HbA1c (± SD) was 72±9.8 mmol/mol (8.7±0.9%). When correlating MG with HbA1c, MG explained 63% of the variation in HbA1c (r=0.79, p<0.001). The variation in HbA1c explained by MG increased to 88% (r=0.94, p value for improvement of fit <0.001) when accounting for person-to-person variation in the MG-HbA1c relationship. Time below range (TBR; <3.9 mmol/l), time above range (TAR) level 2 (>13.9 mmol/l) and glycaemic variability had little or no effect on the association. For a given MG and TIR, the HbA1c of 10% of individuals deviated by >8 mmol/mol (0.8%) from their estimated HbA1c based on the overall association between MG and TIR with HbA1c. TBR and TAR level 2 significantly influenced the association between TIR and HbA1c. At a given TIR, each 1% increase in TBR was related to a 0.6 mmol/mol lower HbA1c (95% CI 0.4, 0.9; p<0.001), and each 2% increase in TAR level 2 was related to a 0.4 mmol/mol higher HbA1c (95% CI 0.1, 0.6; p=0.003). However, neither TIR, TBR nor TAR level 2 were significantly associated with HbA1c when accounting for MG. CONCLUSIONS/INTERPRETATION: Inter-individual variations exist between MG and HbA1c, as well as between TIR and HbA1c, with clinically important deviations in relatively large groups of individuals with type 1 diabetes. These results may provide important information to both healthcare providers and individuals with diabetes in terms of prognosis and when making diabetes management decisions.

7.
J Cell Sci ; 135(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34378783

RESUMO

When the temperature is increased, the heat-shock response is activated to protect the cellular environment. The transcriptomics and proteomics of this process are intensively studied, while information about how the cell responds structurally to heat stress is mostly lacking. Here, Saccharomyces cerevisiae were subjected to a mild continuous heat shock (38°C) and intermittently cryo-immobilised for electron microscopy. Through measuring changes in all distinguishable organelle numbers, sizes and morphologies in over 2100 electron micrographs, a major restructuring of the internal architecture of the cell during the progressive heat shock was revealed. The cell grew larger but most organelles within it expanded even more, shrinking the volume of the cytoplasm. Organelles responded to heat shock at different times, both in terms of size and number, and adaptations of the morphology of some organelles (such as the vacuole) were observed. Multivesicular bodies grew by almost 70%, indicating a previously unknown involvement in the heat-shock response. A previously undescribed electron-translucent structure accumulated close to the plasma membrane. This all-encompassing approach provides a detailed chronological progression of organelle adaptation throughout the cellular heat-stress response.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Citoplasma , Resposta ao Choque Térmico , Temperatura Alta , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Vacúolos
8.
Cardiovasc Diabetol ; 23(1): 88, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424560

RESUMO

Type-2 diabetes (T2D) worsens stroke recovery, amplifying post-stroke disabilities. Currently, there are no therapies targeting this important clinical problem. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are potent anti-diabetic drugs that also efficiently reduce cardiovascular death and heart failure. In addition, SGLT2i facilitate several processes implicated in stroke recovery. However, the potential efficacy of SGLT2i to improve stroke recovery in T2D has not been investigated. Therefore, we determined whether a post-stroke intervention with the SGLT2i Empagliflozin could improve stroke recovery in T2D mice. T2D was induced in C57BL6J mice by 8 months of high-fat diet feeding. Hereafter, animals were subjected to transient middle cerebral artery occlusion and treated with vehicle or the SGLTi Empagliflozin (10 mg/kg/day) starting from 3 days after stroke. A similar study in non diabetic mice was also conducted. Stroke recovery was assessed using the forepaw grip strength test. To identify potential mechanisms involved in the Empagliflozin-mediated effects, several metabolic parameters were assessed. Additionally, neuronal survival, neuroinflammation, neurogenesis and cerebral vascularization were analyzed using immunohistochemistry/quantitative microscopy. Empagliflozin significantly improved stroke recovery in T2D but not in non-diabetic mice. Improvement of functional recovery was associated with lowered glycemia, increased serum levels of fibroblast growth factor-21 (FGF-21), and the normalization of T2D-induced aberration of parenchymal pericyte density. The global T2D-epidemic and the fact that T2D is a major risk factor for stroke are drastically increasing the number of people in need of efficacious therapies to improve stroke recovery. Our data provide a strong incentive for the potential use of SGLT2i for the treatment of post-stroke sequelae in T2D.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Camundongos , Animais , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Compostos Benzidrílicos/farmacologia , Compostos Benzidrílicos/uso terapêutico
9.
Diabetes Obes Metab ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859661

RESUMO

Sodium-glucose cotransporter 2 (SGLT2) inhibitors, originally designed to manage blood sugar levels in individuals with type 2 diabetes (T2D), have emerged as a crucial class of drugs for managing cardio-renal diseases. These drugs work by targeting the SGLT2 protein in the kidneys, promoting the excretion of glucose and influencing metabolic pathways beyond glucose control. The relationship between cardio-renal diseases and SGLT2 inhibitors has been explored through landmark trials and real-world evidence (RWE) studies, demonstrating significant reductions in cardio-renal complications. This review discusses the importance of RWE studies alongside randomized controlled trials in understanding the real-world effectiveness and safety of SGLT2 inhibitors. It outlines the advantages and disadvantages of RWE compared to RCTs, highlighting their complementary roles in providing comprehensive insights into treatment outcomes. By examining a range of RWE studies, the review underscores the cardio-renal benefits of SGLT2 inhibitors across various patient populations. Safety assessments indicate that SGLT2 inhibitors are generally well tolerated, with severe adverse events being rare. Common issues, such as genital mycotic infections and urinary tract infections, are acknowledged, alongside less frequent but significant adverse events including diabetic ketoacidosis, lower-limb amputations, and bone fractures. In summary, SGLT2 inhibitors show promising cardio-renal protective effects in real-world scenarios across diverse populations in T2D, indicating their potential as early intervention measures. Continued research is essential for gaining a thorough understanding of their long-term effects and safety profiles.

10.
PLoS Genet ; 17(1): e1008951, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33428620

RESUMO

70 kDa heat shock proteins (Hsp70) are essential chaperones of the protein quality control network; vital for cellular fitness and longevity. The four cytosolic Hsp70's in yeast, Ssa1-4, are thought to be functionally redundant but the absence of Ssa1 and Ssa2 causes a severe reduction in cellular reproduction and accelerates replicative aging. In our efforts to identify which Hsp70 activities are most important for longevity assurance, we systematically investigated the capacity of Ssa4 to carry out the different activities performed by Ssa1/2 by overproducing Ssa4 in cells lacking these Hsp70 chaperones. We found that Ssa4, when overproduced in cells lacking Ssa1/2, rescued growth, mitigated aggregate formation, restored spatial deposition of aggregates into protein inclusions, and promoted protein degradation. In contrast, Ssa4 overproduction in the Hsp70 deficient cells failed to restore the recruitment of the disaggregase Hsp104 to misfolded/aggregated proteins, to fully restore clearance of protein aggregates, and to bring back the formation of the nucleolus-associated aggregation compartment. Exchanging the nucleotide-binding domain of Ssa4 with that of Ssa1 suppressed this 'defect' of Ssa4. Interestingly, Ssa4 overproduction extended the short lifespan of ssa1Δ ssa2Δ mutant cells to a lifespan comparable to, or even longer than, wild type cells, demonstrating that Hsp104-dependent aggregate clearance is not a prerequisite for longevity assurance in yeast.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico/genética , Longevidade/genética , Proteínas de Saccharomyces cerevisiae/genética , Citosol/metabolismo , Chaperonas Moleculares/genética , Proteínas Mutantes/genética , Mutação/genética , Dobramento de Proteína , Saccharomyces cerevisiae/genética
11.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34290138

RESUMO

Nuclear envelope budding (NEB) is a recently discovered alternative pathway for nucleocytoplasmic communication distinct from the movement of material through the nuclear pore complex. Through quantitative electron microscopy and tomography, we demonstrate how NEB is evolutionarily conserved from early protists to human cells. In the yeast Saccharomyces cerevisiae, NEB events occur with higher frequency during heat shock, upon exposure to arsenite or hydrogen peroxide, and when the proteasome is inhibited. Yeast cells treated with azetidine-2-carboxylic acid, a proline analog that induces protein misfolding, display the most dramatic increase in NEB, suggesting a causal link to protein quality control. This link was further supported by both localization of ubiquitin and Hsp104 to protein aggregates and NEB events, and the evolution of these structures during heat shock. We hypothesize that NEB is part of normal cellular physiology in a vast range of species and that in S. cerevisiae NEB comprises a stress response aiding the transport of protein aggregates across the nuclear envelope.


Assuntos
Ácido Azetidinocarboxílico/toxicidade , Resposta ao Choque Térmico , Membrana Nuclear/fisiologia , Dobramento de Proteína , Proteostase/efeitos dos fármacos , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/crescimento & desenvolvimento , Arsenitos/toxicidade , Peróxido de Hidrogênio/toxicidade , Membrana Nuclear/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Proteínas de Saccharomyces cerevisiae/efeitos dos fármacos , Proteínas de Saccharomyces cerevisiae/metabolismo , Compostos de Sódio/toxicidade , Ubiquitina/metabolismo , Ubiquitinação
12.
J Biol Chem ; 298(11): 102476, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36096201

RESUMO

The accumulation of misfolded proteins is a hallmark of aging and many neurodegenerative diseases, making it important to understand how the cellular machinery recognizes and processes such proteins. A key question in this respect is whether misfolded proteins are handled in a similar way regardless of their genetic origin. To approach this question, we compared how three different misfolded proteins, guk1-7, gus1-3, and pro3-1, are handled by the cell. We show that all three are nontoxic, even though highly overexpressed, highlighting their usefulness in analyzing the cellular response to misfolding in the absence of severe stress. We found significant differences between the aggregation and disaggregation behavior of the misfolded proteins. Specifically, gus1-3 formed some aggregates that did not efficiently recruit the protein disaggregase Hsp104 and did not colocalize with the other misfolded reporter proteins. Strikingly, while all three misfolded proteins generally coaggregated and colocalized to specific sites in the cell, disaggregation was notably different; the rate of aggregate clearance of pro3-1 was faster than that of the other misfolded proteins, and its clearance rate was not hindered when pro3-1 colocalized with a slowly resolved misfolded protein. Finally, we observed using super-resolution light microscopy as well as immunogold labeling EM in which both showed an even distribution of the different misfolded proteins within an inclusion, suggesting that misfolding characteristics and remodeling, rather than spatial compartmentalization, allows for differential clearance of these misfolding reporters residing in the same inclusion. Taken together, our results highlight how properties of misfolded proteins can significantly affect processing.


Assuntos
Doenças Neurodegenerativas , Proteínas de Saccharomyces cerevisiae , Humanos , Agregados Proteicos , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Doenças Neurodegenerativas/metabolismo , Dobramento de Proteína , Proteínas de Choque Térmico/metabolismo , Guanilato Quinases/metabolismo
13.
J Cell Sci ; 134(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34085697

RESUMO

The toxic metalloid arsenic causes widespread misfolding and aggregation of cellular proteins. How these protein aggregates are formed in vivo, the mechanisms by which they affect cells and how cells prevent their accumulation is not fully understood. To find components involved in these processes, we performed a genome-wide imaging screen and identified Saccharomyces cerevisiae deletion mutants with either enhanced or reduced protein aggregation levels during arsenite exposure. We show that many of the identified factors are crucial to safeguard protein homeostasis (proteostasis) and to protect cells against arsenite toxicity. The hits were enriched for various functions including protein biosynthesis and transcription, and dedicated follow-up experiments highlight the importance of accurate transcriptional and translational control for mitigating protein aggregation and toxicity during arsenite stress. Some of the hits are associated with pathological conditions, suggesting that arsenite-induced protein aggregation may affect disease processes. The broad network of cellular systems that impinge on proteostasis during arsenic stress identified in this current study provides a valuable resource and a framework for further elucidation of the mechanistic details of metalloid toxicity and pathogenesis. This article has an associated First Person interview with the first authors of the paper.


Assuntos
Arsênio , Arsenitos , Proteínas de Saccharomyces cerevisiae , Arsenitos/toxicidade , Agregados Proteicos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
14.
Cardiovasc Diabetol ; 22(1): 337, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066597

RESUMO

BACKGROUND: Subjects with type 2 diabetes (T2D) have a higher risk of in-stent restenosis and stent thrombosis. The activation of the glucagon-like peptide-1 receptor (GLP-1R) has been suggested to induce several effects on the vasculature that may reduce the risk of stent failure following an angioplasty. The aim of this study is to evaluate the effect of the GLP-1R agonist exenatide on endothelialization of a modern drug-eluting stent (DES) in subjects with T2D. METHODS: 38 subjects with T2D who were eligible for revascularization with implantation of DES were randomized to treatment with exenatide (once weekly) plus standard treatment, or to standard treatment alone. After 12 weeks, a new coronary angiography was performed to evaluate the percentage of strut coverage (primary endpoint) and the presence of neo-atherosclerosis by optical coherence tomography. This study was approved by the Stockholm's Ethical Review Board. RESULTS: The two groups were well balanced regarding baseline clinical characteristics. Strut coverage was 95% (88.7-98.5%) in the exenatide group and 91.4% (88.8-98.5%) in the control group (p = 0.692). There were no significant differences between groups neither in the thickness of neo-intima (0.2 mm in both groups, p = 0.471), nor the maximal in-stent obstruction by neo-intima (15.5% in exenatide group vs 14.7% in control group, p = 0.801). No significant differences were detected in the rate of target lesion revascularization between groups (p = 0.224). CONCLUSION: Twelve weeks treatment with exenatide did not lead to a significantly better stent coverage in people with T2D. No significant differences in the occurrence of neo-atherosclerosis were detected between groups. TRIAL REGISTRATION: The study was registered at www. CLINICALTRIALS: gov (Rebuild Study, NCT02621489).


Assuntos
Diabetes Mellitus Tipo 2 , Exenatida , Intervenção Coronária Percutânea , Humanos , Aterosclerose/patologia , Angiografia Coronária , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/etiologia , Reestenose Coronária/patologia , Vasos Coronários/patologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Stents Farmacológicos , Exenatida/uso terapêutico , Stents , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento
15.
Cardiovasc Diabetol ; 22(1): 61, 2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36935526

RESUMO

AIMS: The aim of this study was to investigate the association between estimated glucose disposal rate (eGDR), a proxy for insulin resistance, and retinopathy or kidney disease, i.e. micro-, or macroalbuminuria, in young individuals with type 1 diabetes (T1D). MATERIAL AND METHODS: Using data from the Swedish pediatric registry for diabetes (SweDiabKids) and the registry for adults (NDR), all individuals with T1D with a duration of diabetes of less than 10 years between 1998 and 2017 were included. We calculated the crude incidence rates with 95% confidence intervals (CIs) and used multivariable Cox regression to estimate crude and adjusted hazard ratios (HRs) for two cohorts: retinopathy cohort or kidney disease cohort, stratified by eGDR categories: < 4, 4 to 5.99, 6 to 7.99, and ≥ 8 mg/kg/min (reference). RESULTS: A total of 22 146 (10 289 retinopathy cohort, and 11 857 kidney disease cohort with an overlapping of 9575) children and adults with T1D (median age 21 years, female 42% and diabetes duration of 6 and 7 years, respectively for the cohorts) were studied. During a median follow-up of 4.8 years (IQR 2.6-7.7) there were 5040 (24.7%), 1909 (48.1%), 504 (52.3%) and 179 (57.6%) events for retinopathy in individuals with an eGDR ≥ 8, 7.99 to 6, 5.99 to 4, and < 4 mg/kg/min, respectively. Corresponding numbers for kidney disease was 1321 (6.5%), 526 (13.3%), 255 (26.8%) and 145 (46.6%). After multiple adjustments for different covariates, individuals with an eGDR 7.99 to 6, 5.99 to 4 and < 4 mg/kg/min, had an increased risk of retinopathy compared to those with an eGDR ≥ 8 mg/kg/min (adjusted HRs, 95% CIs) 1.29 (1.20 to 1.40); 1.50 (1.31 to 1.71) and 1.74 (1.41 to 2.14). Corresponding numbers for kidney disease was (adjusted HRs, 95% CIs) 1.30 (1.11 to 1.52); 1.58 (1.25 to 1.99) and 1.33 (0.95 to 1.86), respectively. CONCLUSIONS: eGDR, a proxy for insulin resistance, is associated with retinopathy and kidney disease in young adults with T1D. The risk of retinopathy increased with lower eGDR. The risk of kidney disease also increased with lower eGDR; however results show no association between the lowest eGDR and kidney disease. eGDR can be helpful to identify young T1D individuals at risk.


Assuntos
Diabetes Mellitus Tipo 1 , Resistência à Insulina , Nefropatias , Doenças Retinianas , Adulto Jovem , Humanos , Feminino , Criança , Adolescente , Adulto , Glucose , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/complicações , Doenças Retinianas/complicações , Glicemia
16.
Cardiovasc Diabetol ; 22(1): 233, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653496

RESUMO

BACKGROUND: Studies that have reported lower risk for cardiovascular outcomes in users of Sodium-Glucose Cotransporter-2 Inhibitors (SGLT-2i) are limited by residual cofounding and lack of information on prior cardiovascular disease (CVD). This study compared risk of cardiovascular events in patients within routine care settings in Europe and Asia with type 2 diabetes (T2D) initiating empagliflozin compared to dipeptidyl peptidase-4 inhibitors (DPP-4i) stratified by pre-existing CVD and history of heart failure (HF). METHODS AND RESULTS: Adults initiating empagliflozin and DPP-4i in 2014-2018/19 from 11 countries in Europe and Asia were compared using propensity score matching and Cox proportional hazards regression to assess differences in rates of primary outcomes: hospitalisation for heart failure (HHF), myocardial infarction (MI), stroke; and secondary outcomes: cardiovascular mortality (CVM), coronary revascularisation procedure, composite outcome including HHF or CVM, and 3-point major adverse cardiovascular events (MACE: MI, stroke and CVM). Country-specific results were meta-analysed and pooled hazard ratios (HR) with 95% confidence intervals (CI) from random-effects models are presented. In total, 85,244 empagliflozin/DPP4i PS-matched patient pairs were included with overall mean follow-up of 0.7 years. Among those with pre-existing CVD, lower risk was observed for HHF (HR 0.74; 95% CI 0.64-0.86), CVM (HR 0.55; 95% CI 0.38-0.80), HHF or CVM (HR 0.57; 95% CI 0.48-0.67) and stroke (HR 0.79; 95% CI 0.67-0.94) in patients initiating empagliflozin vs DPP-4i. Similar patterns were observed among patients without pre-existing CVD and those with and without pre-existing HF. CONCLUSION: These results from diverse patient populations in routine care settings across Europe and Asia demonstrate that initiation of empagliflozin compared to DPP-4i results in favourable cardioprotective effects regardless of pre-existing CVD or HF status.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Insuficiência Cardíaca , Infarto do Miocárdio , Inibidores do Transportador 2 de Sódio-Glicose , Acidente Vascular Cerebral , Humanos , Adulto , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Fatores de Risco , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Ásia/epidemiologia , Europa (Continente)/epidemiologia , Fatores de Risco de Doenças Cardíacas , Dipeptidil Peptidases e Tripeptidil Peptidases
17.
Cell Commun Signal ; 21(1): 220, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620860

RESUMO

The calcium-responsive phosphatase, calcineurin, senses changes in Ca2+ concentrations in a calmodulin-dependent manner. Here we report that under non-stress conditions, inactivation of calcineurin signaling or deleting the calcineurin-dependent transcription factor CRZ1 triggered the formation of chaperone Hsp100p (Hsp104p)-associated protein aggregates in Saccharomyces cerevisiae. Furthermore, calcineurin inactivation aggravated α-Synuclein-related cytotoxicity. Conversely, elevated production of the calcineurin activator, Cnb1p, suppressed protein aggregation and cytotoxicity associated with the familial Parkinson's disease-related mutant α-Synuclein A53T in a partly CRZ1-dependent manner. Activation of calcineurin boosted normal localization of both wild type and mutant α-synuclein to the plasma membrane, an intervention previously shown to mitigate α-synuclein toxicity in Parkinson's disease models. The findings demonstrate that calcineurin signaling, and Ca2+ influx to the vacuole, limit protein quality control in non-stressed cells and may have implications for elucidating to which extent aberrant calcineurin signaling contributes to the progression of Parkinson's disease(s) and other synucleinopathies. Video Abstract.


Assuntos
Doença de Parkinson , Proteínas de Saccharomyces cerevisiae , Sinucleinopatias , Humanos , alfa-Sinucleína , Agregados Proteicos , Calcineurina , Saccharomyces cerevisiae , Proteínas de Ligação a DNA , Fatores de Transcrição
18.
Diabetes Obes Metab ; 25(1): 261-271, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36097728

RESUMO

AIMS: To evaluate effectiveness and healthcare resource utilization (HCRU) of empagliflozin versus dipeptidyl peptidase-4 inhibitors (DPP-4i) in Swedish clinical practice, as part of the EMPRISE EU study (EUPAS27606, NCT03817463). MATERIALS AND METHODS: A non-interventional, cohort study using retrospectively collected data from Swedish national registries. Adults with type 2 diabetes newly initiated on empagliflozin or DPP-4i from May 2014 to December 2018 were matched 1:1 using propensity scores based on >180 covariates. Cardiovascular outcomes included hospitalization for heart failure (HHF), all-cause mortality (ACM), myocardial infarction (MI), stroke and cardiovascular mortality (CVM), as well as their composite outcomes. Renal outcomes included end-stage renal disease (ESRD), estimated glomerular filtration rate (eGFR) decline to <60 ml/min/1.73 m2 and progression to micro/macroalbuminuria. HCRU outcomes were also assessed. Comparisons were done using Cox proportional hazards and Poisson regression models. RESULTS: Overall, 15,785 matched-pairs were identified, with a mean follow-up of 6.4 and 9.7 months for patients initiating empagliflozin versus DPP-4i, respectively. Empagliflozin was associated with significant reduction in rates of HHF (hazard ratio [HR] = 0.67; 95% confidence interval: 0.49-0.91), ACM (HR = 0.53; 0.41-0.68), HHF + ACM (HR = 0.59; 0.48-0.73), MI + stroke + ACM (HR = 0.68; 0.57-0.81), CVM (HR = 0.46; 0.29-0.73), HHF + CVM (HR = 0.61; 0.47-0.79) and MI + stroke + CVM (HR = 0.79; 0.63-0.98) versus DPP-4i. Empagliflozin also reduced the rates of ESRD (HR = 0.13; 0.03-0.57) and eGFR decline (HR = 0.83; 0.70-0.99). Regarding HCRU, empagliflozin was associated with lower risk of first inpatient stay (HR = 0.87; 0.81-0.93), and lower rate of inpatient and outpatient visits (rate ratio [RR] = 0.85; 0.80-0.89 and RR = 0.96; 0.94-0.98) than DPP-4i. CONCLUSIONS: Empagliflozin treatment compared to DPP-4i reduced cardiorenal events and overall mortality, which may explain lower HCRU among empagliflozin users in Sweden.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Acidente Vascular Cerebral , Humanos , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Estudos de Coortes , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Atenção à Saúde , Dipeptidil Peptidases e Tripeptidil Peptidases
19.
Mol Cell ; 77(5): 927-929, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32142688
20.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36835405

RESUMO

Type 2 diabetes (T2D) impairs post-stroke recovery, and the underlying mechanisms are unknown. Insulin resistance (IR), a T2D hallmark that is also closely linked to aging, has been associated with impaired post-stroke recovery. However, whether IR worsens stroke recovery is unknown. We addressed this question in mouse models where early IR, with or without hyperglycemia, was induced by chronic high-fat diet feeding or sucrose supplementation in the drinking water, respectively. Furthermore, we used 10-month-old mice, spontaneously developing IR but not hyperglycemia, where IR was normalized pharmacologically pre-stroke with Rosiglitazone. Stroke was induced by transient middle cerebral artery occlusion and recovery was assessed by sensorimotor tests. Neuronal survival, neuroinflammation and the density of striatal cholinergic interneurons were also assessed by immunohistochemistry/quantitative microscopy. Pre-stroke induction and normalization of IR, respectively, worsened and improved post-stroke neurological recovery. Moreover, our data indicate a potential association of this impaired recovery with exacerbated neuroinflammation and a decreased density of striatal cholinergic interneurons. The global diabetes epidemic and population aging are dramatically increasing the percentage of people in need of post-stroke treatment/care. Our results suggest that future clinical studies should target pre-stroke IR to reduce stroke sequelae in both diabetics and elderly people with prediabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Resistência à Insulina , Acidente Vascular Cerebral , Camundongos , Animais , Doenças Neuroinflamatórias , Infarto da Artéria Cerebral Média
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