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1.
Proc Natl Acad Sci U S A ; 120(42): e2309843120, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37812725

RESUMO

The burst firing of midbrain dopamine neurons releases a phasic dopamine signal that mediates reinforcement learning. At many synapses, however, high firing rates deplete synaptic vesicles (SVs), resulting in synaptic depression that limits release. What accounts for the increased release of dopamine by stimulation at high frequency? We find that adaptor protein-3 (AP-3) and its coat protein VPS41 promote axonal dopamine release by targeting vesicular monoamine transporter VMAT2 to the axon rather than dendrites. AP-3 and VPS41 also produce SVs that respond preferentially to high-frequency stimulation, independent of their role in axonal polarity. In addition, conditional inactivation of VPS41 in dopamine neurons impairs reinforcement learning, and this involves a defect in the frequency dependence of release rather than the amount of dopamine released. Thus, AP-3 and VPS41 promote the axonal polarity of dopamine release but enable learning by producing a distinct population of SVs tuned specifically to high firing frequency that confers the phasic release of dopamine.


Assuntos
Dopamina , Vesículas Sinápticas , Dopamina/metabolismo , Vesículas Sinápticas/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/genética , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Axônios/metabolismo , Mesencéfalo/metabolismo
2.
J Biol Chem ; 299(5): 104646, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36965620

RESUMO

The solute carrier 17 family transports diverse organic anions using two distinct modes of coupling to a source of energy. Transporters that package glutamate and nucleotide into secretory vesicles for regulated release by exocytosis are driven by membrane potential but subject to allosteric regulation by H+ and Cl-. Other solute carrier 17 members including the lysosomal sialic acid exporter couple the flux of organic anion to cotransport of H+. To begin to understand how similar proteins can perform such different functions, we have studied Escherichia coli DgoT, a H+/galactonate cotransporter. A recent structure of DgoT showed many residues contacting D-galactonate, and we now find that they do not tolerate even conservative substitutions. In contrast, the closely related lysosomal H+/sialic acid cotransporter Sialin tolerates similar mutations, consistent with its recognition of diverse substrates with relatively low affinity. We also find that despite coupling to H+, DgoT transports more rapidly but with lower apparent affinity at high pH. Indeed, membrane potential can drive uptake, indicating electrogenic transport and suggesting a H+:galactonate stoichiometry >1. Located in a polar pocket of the N-terminal helical bundle, Asp46 and Glu133 are each required for net flux by DgoT, but the E133Q mutant exhibits robust exchange activity and rescues exchange by D46N, suggesting that these two residues operate in series to translocate protons. E133Q also shifts the pH sensitivity of exchange by DgoT, supporting a central role for the highly conserved TM4 glutamate in H+ coupling by DgoT.


Assuntos
Proteínas de Escherichia coli , Prótons , Simportadores , Ânions/metabolismo , Transporte Biológico , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Mutação , Simportadores/genética , Simportadores/metabolismo
3.
J Transl Med ; 22(1): 160, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365769

RESUMO

BACKGROUND: Telomere length has long been recognized as a valuable biomarker of aging and is inversely correlated with chronological age. Various lifestyle factors have been implicated in telomere shortening or preservation; however, the association between lifestyle factors and telomere length remains controversial. To address this issue, we conducted a Mendelian randomization (MR) analysis to investigate the potential causal associations between multiple lifestyle factors and telomere length. METHODS: Independent genetic variants strongly associated with lifestyle factors (tobacco smoking, sleep duration, insomnia, and physical activity) were selected as instrumental variables from corresponding genome-wide association studies (GWASs). Summary-level data for telomere length was obtained from a GWAS comprising 472,174 European ancestries. Univariable and multivariable MR analyses were performed to assess the relationships. RESULTS: The genetic liability to lifetime smoking was robustly associated with shorter telomere length (odd ratio [OR]: 0.882; 95% confidence interval [CI]: 0.847-0.918). Genetically predicted insomnia was also linked to shorter telomere length (OR: 0.972; 95% CI: 0.959-0.985), while no significant association was observed between sleep duration and telomere length. Furthermore, a suggestive association was found between moderate-to-vigorous physical activity and longer telomere length (OR: 1.680; 95% CI: 1.115-2.531). In multivariable MR analyses, adjusting for potential mediators such as body mass index, type 2 diabetes, alcohol consumption, and alcohol use disorder, the associations of lifetime smoking and insomnia with telomere length remained robust. CONCLUSION: Our findings suggest that smoking and insomnia may contribute to telomere shortening, while physical activity may play a role in telomere length maintenance. These findings underscore the importance of managing positive risk factors and adopting a healthy lifestyle to promote telomere health.


Assuntos
Diabetes Mellitus Tipo 2 , Distúrbios do Início e da Manutenção do Sono , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Telômero/genética , Polimorfismo de Nucleotídeo Único
4.
Angew Chem Int Ed Engl ; : e202406637, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880766

RESUMO

A critical challenge in solid polymer lithium batteries is developing a polymer matrix that can harmonize ionic transportation, electrochemical stability, and mechanical durability. We introduce a novel polymer matrix design by deciphering the structure-function relationships of polymer side chains. Leveraging the molecular orbital-polarity-spatial freedom design strategy, a high ion-conductive hyperelastic ternary copolymer electrolyte (CPE) is synthesized, incorporating three functionalized side chains of poly-2,2,2-Trifluoroethyl acrylate (PTFEA), poly(vinylene carbonate) (PVC), and polyethylene glycol monomethyl ether acrylate (PEGMEA). It is revealed that fluorine-rich side chain (PTFEA) contributes to improved stability and interfacial compatibility; the highly polar side chain (PVC) facilitates the efficient dissociation and migration of ions; the flexible side chain (PEGMEA) with high spatial freedom promotes segmental motion and interchain ion exchanges. The resulting CPE demonstrates an ionic conductivity of 2.19 × 10-3 S cm-1 (30 °C), oxidation resistance voltage of 4.97 V, excellent elasticity (2700%), and non-flammability. The outer elastic CPE and the inner organic-inorganic hybrid SEI buffer intense volume fluctuation and enable uniform Li+ deposition. As a result, symmetric Li cells realize a high CCD of 2.55 mA cm-2 and the CPE-based Li||NCM811 full cell exhibits a high-capacity retention (~90%, 0.5 C) after 200 cycles.

5.
Inorg Chem ; 62(37): 15094-15103, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37655947

RESUMO

The wide application of KNN-based lead-free piezoelectric ceramics is constrained by the contradictory relationship between its mechanical quality factor and piezoelectric constant. From an application point of view, searching for chemical composition with enhanced piezoelectric constant (d33) and mechanical quality factor (Qm) is one of the key points of KNN-based ceramics. In this work, KNN-based ceramics with enhanced d33 and high Qm values were obtained by the solid solution method via a donor-acceptor codoping strategy. The donor dopant Ho3+ enhanced d33 values by refining the domain size, while the acceptor dopant (Cu1/3Nb2/3)4+ improved Qm by the formation of defect dipoles. The composition (KNN-5Ho-4CN) exhibits optimal integrated performances, of which d33, Qm, and TC values are 120 pC/N, 850, and 392 °C, respectively. Moreover, the temperature coefficient of resonant frequency (TCF = -429 ppm/K) indicates that KNN-5Ho-4CN ceramic has good temperature stability. This work provides a new insight for developing KNN-based ceramics with enhanced d33 and high Qm.

6.
Cell Biol Toxicol ; 39(4): 1413-1431, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36131165

RESUMO

AIMS: We aimed to investigate the effect and mechanism of pleiotropic chemokine CCL24 in heart failure. METHODS AND RESULTS: Compared with normal donators, the expression of CCL24 and number of cardiac M2 macrophages in heart were higher in heart failure patients, the same as plasma CCL24. Treatment with CCL24 antibody hindered Ang II (1500 ng/kg/min)-induced cardiac adverse remodeling through preventing cardiac hypertrophy and fibrosis. RNA-seq showed that CCL24/CCR3 axis was involved in immune and inflammatory responses. Single-cell analysis of cytometry by time of flight (CyTOF) revealed that CCL24 antibody decreased the M2 macrophage and monocyte polarization during Ang II stimulation. Immunofluorescence co-localization analysis confirmed the expression of CCR3 in macrophage and fibroblasts. Then, in vitro experiments confirmed that CCL24/CCR3 axis was also involved in cardiac primary fibroblast activation through its G protein-coupled receptor function. CONCLUSION: CCL24/CCR3 axis plays a crucial part in cardiac remodeling by stimulating M2 macrophage polarization and cardiac fibroblast activation. Cardiac M2 macrophages, CCL24 and circulation CCL24 increased in heart failure patients. Treatment with CCL24 Ab hindered Ang II induced cardiac structural dysfunction and electrical remodeling. In CCL24 Ab group RNA-seq found that it was related to immune responses and hypertrophic cardiomyopathy, CytoF revealed M2 macrophages and monocytes decreased obviously. In vitro,CCL24 promoted activation and migration of cardiac fibroblast.


Assuntos
Angiotensina II , Insuficiência Cardíaca , Humanos , Animais , Camundongos , Quimiocina CCL24/metabolismo , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Macrófagos/metabolismo , Insuficiência Cardíaca/metabolismo , Fibroblastos , Camundongos Endogâmicos C57BL , Receptores CCR3/metabolismo
7.
Int J Mol Sci ; 24(21)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37958661

RESUMO

Exosomes, as potent intercellular communication tools, have garnered significant attention due to their unique cargo-carrying capabilities, which enable them to influence diverse physiological and pathological functions. Extensive research has illuminated the biogenesis, secretion, and functions of exosomes. These vesicles are secreted by cells in different states, exerting either protective or harmful biological functions. Emerging evidence highlights their role in cardiovascular disease (CVD) by mediating comprehensive interactions among diverse cell types. This review delves into the significant impacts of exosomes on CVD under stress and disease conditions, including coronary artery disease (CAD), myocardial infarction, heart failure, and other cardiomyopathies. Focusing on the cellular signaling and mechanisms, we explore how exosomes mediate multifaceted interactions, particularly contributing to endothelial dysfunction, oxidative stress, and apoptosis in CVD pathogenesis. Additionally, exosomes show great promise as biomarkers, reflecting differential expressions of NcRNAs (miRNAs, lncRNAs, and circRNAs), and as therapeutic carriers for targeted CVD treatment. However, the specific regulatory mechanisms governing exosomes in CVD remain incomplete, necessitating further exploration of their characteristics and roles in various CVD-related contexts. This comprehensive review aims to provide novel insights into the biological implications of exosomes in CVD and offer innovative perspectives on the diagnosis and treatment of CVD.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Exossomos , MicroRNAs , Infarto do Miocárdio , Humanos , Exossomos/metabolismo , Doenças Cardiovasculares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Doença da Artéria Coronariana/metabolismo
8.
J Pathol ; 255(4): 438-450, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34467534

RESUMO

The mevalonate pathway is essential for cholesterol biosynthesis. Previous studies have suggested that the key enzyme in this pathway, farnesyl diphosphate synthase (FDPS), regulates the cardiovascular system. We used human samples and mice that were deficient in cardiac FDPS (c-Fdps-/- mice) to investigate the role of FDPS in cardiac homeostasis. Cardiac function was assessed using echocardiography. Left ventricles were examined and tested for histological and molecular markers of cardiac remodeling. Our results showed that FDPS levels were downregulated in samples from patients with cardiomyopathy. Furthermore, c-Fdps-/- mice exhibited cardiac remodeling and dysfunction. This dysfunction was associated with abnormal activation of Ras and Rheb, which may be due to the accumulation of geranyl pyrophosphate. Activation of Ras and Rheb stimulated downstream mTOR and ERK pathways. Moreover, administration of farnesyltransferase inhibitors attenuated cardiac remodeling and dysfunction in c-Fdps-/- mice. These results indicate that FDPS plays an important role in cardiac homeostasis. Deletion of FDPS stimulates the downstream mTOR and ERK signaling pathways, resulting in cardiac remodeling and dysfunction. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Cardiomiopatias/patologia , Proteínas de Ligação ao GTP/metabolismo , Geraniltranstransferase/metabolismo , Remodelação Ventricular/fisiologia , Animais , Humanos , Camundongos
9.
BMC Psychiatry ; 22(1): 399, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705942

RESUMO

BACKGROUND: Observational studies suggest that sleep disturbances are commonly associated with schizophrenia. However, it is uncertain whether this relationship is causal. To investigate the bidirectional causal relation between sleep traits and schizophrenia, we performed a two-sample bidirectional Mendelian randomization (MR) study with the fixed effects inverse-variance weighted (IVW) method. METHODS: As genetic variants for sleep traits, we selected variants from each meta-analysis of genome-wide association studies (GWASs) conducted using data from the UK Biobank (UKB). RESULTS: We found that morning diurnal preference was associated with a lower risk of schizophrenia, while long sleep duration and daytime napping were associated with a higher risk of schizophrenia. Multivariable MR analysis also showed that sleep duration was associated with a higher risk of schizophrenia after adjusting for other sleep traits. Furthermore, genetically predicted schizophrenia was negatively associated with morning diurnal preference and short sleep duration and was positively associated with daytime napping and long sleep duration. CONCLUSIONS: Therefore, sleep traits were identified as a potential treatment target for patients with schizophrenia.


Assuntos
Esquizofrenia , Transtornos do Sono-Vigília , Estudo de Associação Genômica Ampla , Humanos , Análise da Randomização Mendeliana , Fenótipo , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Sono/genética , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/genética
10.
Pestic Biochem Physiol ; 184: 105076, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715031

RESUMO

Chemosensory proteins (CSPs) are a class of small transporter proteins expressed only in arthropods with various functions beyond chemoreception. Previous studies have been reported that CSPs are involved in the insecticide resistance. In this study, we found that AgoCSP1, AgoCSP4, and AgoCSP5 were constitutively overexpressed in an insecticide-resistant strain of Aphis gossypii and showed higher expression in broad body tissue (including fat bodies) than in the midgut but without tissue specificity. However, the function of these three upregulated AgoCSPs remains unknown. Here, we investigated the function of AgoCSPs in resistance to the diamide insecticide cyantraniliprole. Suppression of AgoCSP1, AgoCSP4 and AgoCSP5 transcription by RNAi significantly increased the sensitivity of resistant aphids to cyantraniliprole. Molecular docking and competitive binding assays indicated that these AgoCSPs bind moderate with cyantraniliprole. Transgenic Drosophila melanogaster expressing these AgoCSPs in the broad body or midgut showed higher tolerance to cyantraniliprole than control flies with the same genetic background; AgoCSP4 was more effective in broad body tissue, and AgoCSP1 and AgoCSP5 were more effective in the midgut, indicating that broad body and midgut tissues may be involved in the insecticide resistance mediated by the AgoCSPs examined. The present results strongly indicate that AgoCSPs participate in xenobiotic detoxification by sequestering and masking toxic insecticide molecules, providing insights into new factors involved in resistance development in A. gossypii.


Assuntos
Afídeos , Inseticidas , Animais , Afídeos/genética , Diamida , Drosophila melanogaster , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Simulação de Acoplamento Molecular , Pirazóis , ortoaminobenzoatos
11.
Pestic Biochem Physiol ; 184: 105104, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35715043

RESUMO

Cyantraniliprole, a second-generation anthranilic diamide insecticide, is widely used to control chewing and sucking pests. ATP-binding cassette transporters (ABCs) are a ubiquitous family of membrane proteins that play important roles in insect detoxification mechanisms. However, the potential effects of ABCs on cyantraniliprole-resistance remain unclear. In the present study, synergism bioassays revealed that verapamil, an ABC inhibitor, increased the toxicity of cyantraniliprole by 2.00- and 12.25-fold in the susceptible and cyantraniliprole-resistant strains of Aphis gossypii. Based on transcriptome data, the expression levels of ABCB4, ABCB5, ABCD1, ABCG4, ABCG7, ABCG13, ABCG16, ABCG17, ABCG26 and MRP12 were upregulated 1.56-, 1.32-, 1.51-, 2.03-, 1.65-, 1.50-, 4.18-, 6.07-, 4.68- and 4.69-fold, respectively, in the cyantraniliprole-resistant strain (CyR) compared to the susceptible strain (SS), as determined using RT-qPCR. Drosophila melanogaster ectopically overexpressing ABCB5, ABCG4, ABCG7, ABCG16, ABCG17, ABCG26 and MRP12 exhibited significantly increased tolerance to cyantraniliprole by 11.71-, 2.39-, 4.85-, 2.06-, 3.75-, 4.20- and 3.50-fold, respectively, with ABCB5 and ABCG family members being the most effective. Furthermore, the suppression of ABCB5, ABCG4, ABCG7, ABCG16, ABCG17, ABCG26 and MRP12 significantly increased the sensitivity of the CyR strain to cyantraniliprole. These results indicate that ABCs may play crucial roles in cyantraniliprole resistance and may provide information for shaping resistance management strategies.


Assuntos
Afídeos , Inseticidas , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Drosophila melanogaster/metabolismo , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Pirazóis , ortoaminobenzoatos/farmacologia
12.
Int J Mol Sci ; 23(4)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35216472

RESUMO

Chemosensory proteins (CSPs) are a class of transporters in arthropods. Deeper research on CSPs showed that CSPs may be involved in some physiological processes beyond chemoreception, such as insect resistance to pesticides. We identified two upregulated CSPs in two resistant strains of Aphis gossypii Glover. To understand their role in the resistance of aphids to pesticides, we performed the functional verification of CSP1 and CSP4 in vivo and in vitro. Results showed that the sensitivity of the thiamethoxam-resistant strain to thiamethoxam increased significantly with the silencing of CSP1 and CSP4 by RNAi (RNA interference), and the sensitivity of the spirotetramat-resistant strain to spirotetramat increased significantly with the silencing of CSP4. Transgenic Drosophila melanogaster expressing CSPs exhibited stronger resistance to thiamethoxam, spirotetramat, and alpha-cypermethrin than the control did. In the bioassay of transgenic Drosophila, CSPs showed different tolerance mechanisms for different pesticides, and the overexpressed CSPs may play a role in processes other than resistance to pesticides. In brief, the present results prove that CSPs are related to the resistance of cotton aphids to insecticides.


Assuntos
Afídeos/metabolismo , Compostos Aza/metabolismo , Resistência a Inseticidas , Proteínas de Membrana Transportadoras/metabolismo , Compostos de Espiro/metabolismo , Tiametoxam/metabolismo , Animais , Animais Geneticamente Modificados , Afídeos/efeitos dos fármacos , Afídeos/fisiologia , Drosophila melanogaster/genética , Proteínas de Insetos/metabolismo , Inseticidas/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-36401781

RESUMO

Total anomalous pulmonary venous drainage (TAPVD) is encountered less frequently in infancy than various other congenital cardiac anomalies. We present a 4-week-old boy with a hitherto unreported variant of TAPVD who died suddenly soon after presentation to our emergency department. At autopsy, we found both pulmonary veins draining abnormally into the pulmonary artery and an atrial septal defect. We wish to emphasize that examination of the major vessels and their connections should be done in situ in all autopsies of unexpected deaths in infants and children, even if there were no symptoms and signs in the ante-mortem period and despite the clinical picture not being suggestive of TAPVD.

14.
Pestic Biochem Physiol ; 176: 104879, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34119222

RESUMO

Cytochrome P450 monooxygenases (P450s) and UDP-glycosyltransferases (UGTs) are major detoxifying enzymes that metabolize plant toxins and insecticides. In the present study, the synergists of piperonyl butoxide, sulfinpyrazone and 5-nitrouracil significantly increased cyantraniliprole and α-cypermethrin toxicity against the resistant strain. The transcripts of UGT341A4, UGT344B4, UGT344D6, UGT344J2 and UGT344M2 increased significantly in the CyR strain compared with the susceptible strain. Among these upregulated genes (including P450s), CYP6CY7 and UGT344B4 were highly expressed in the midgut. Transgenic expression of the P450 and UGT genes in broad body tissues in Drosophila melanogaster indicated that the expression of CYP380C6, CYP4CJ1, UGT341A4, UGT344B4 and UGT344M2 is sufficient to confer cyantraniliprole resistance, and CYP380C6, CYP6CY7, CYP6CY21, UGT341A4 and UGT344M2 are related to α-cypermethrin cross-resistance. The midgut-specific overexpression of CYP380C6, CYP6CY7, CYP6CY21, CYP4CJ1, UGT341A4, UGT344B4 and UGT344M2 significantly increased insensitivity to cyantraniliprole, and CYP380C6, CYP6CY7, CYP6CY21, UGT344B4 and UGT344M2 confer α-cypermethrin cross-resistance. The expression of CYP380C6, CYP4CJ1, UGT341A4 and UGT344M2 in broad tissues or in midgut has similar effects on insensitivity to insecticides; however, CYP6CY7, CYP6CY21 and UGT344B4 are more effective in the midgut. This result indicates that broad body tissues and midgut tissue are involved in insecticide resistance mediated by the candidate P450s and UGTs examined.


Assuntos
Inseticidas , Difosfato de Uridina , Animais , Sistema Enzimático do Citocromo P-450/genética , Drosophila melanogaster , Glicosiltransferases/genética , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Pirazóis , ortoaminobenzoatos
15.
Pestic Biochem Physiol ; 179: 104972, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34802522

RESUMO

Long non-coding RNAs (lncRNAs) represent the largest class of non-coding transcripts. They act a pivotal part in various insect developmental processes and stress responses. However, the investigation of lncRNA functions in insecticide resistant remains at an early phase. Herein, we conducted whole-transcriptome RNA sequencing for two cotton aphid (Aphis gossypii Glover) strains, i.e., insecticide-susceptible (SS) and spirotetramat-resistant (SR). We discovered 6059 lncRNAs in the RNA-Seq data, and 874 lncRNAs showed differential expression. In addition, 5 lncRNAs among 874 lncRNAs were predicted as targets of acetyl-CoA carboxylase (ACC). Reverse transcription real-time quantitative PCR (RT-qPCR) combined with RNA interference (RNAi) confirmed that selected ACC lncRNA was related to the expression of ACC. Moreover, we also identified two transcription factors, i.e., C/EBP and C/EBPzeta, that regulate the transcription level of ACC lncRNA. These results provide a good basis for the study of cotton aphid lncRNA functions in insecticide resistance development.


Assuntos
Afídeos , Compostos Aza , RNA Longo não Codificante , Acetil-CoA Carboxilase/genética , Animais , Afídeos/genética , Resistência a Inseticidas/genética , RNA Longo não Codificante/genética , Compostos de Espiro
16.
J Physiol ; 597(15): 3927-3950, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31206177

RESUMO

KEY POINTS: Women with polycystic ovary syndrome (PCOS) commonly suffer from miscarriage, but the underlying mechanisms remain unknown. Herein, pregnant rats chronically treated with 5α-dihydrotestosterone (DHT) and insulin exhibited hyperandrogenism and insulin resistance, as well as increased fetal loss, and these features are strikingly similar to those observed in pregnant PCOS patients. Fetal loss in our DHT+insulin-treated pregnant rats was associated with mitochondrial dysfunction, disturbed superoxide dismutase 1 and Keap1/Nrf2 antioxidant responses, over-production of reactive oxygen species (ROS) and impaired formation of the placenta. Chronic treatment of pregnant rats with DHT or insulin alone indicated that DHT triggered many of the molecular pathways leading to placental abnormalities and fetal loss, whereas insulin often exerted distinct effects on placental gene expression compared to co-treatment with DHT and insulin. Treatment of DHT+insulin-treated pregnant rats with the antioxidant N-acetylcysteine improved fetal survival but was deleterious in normal pregnant rats. Our results provide insight into the fetal loss associated with hyperandrogenism and insulin resistance in women and suggest that physiological levels of ROS are required for normal placental formation and fetal survival during pregnancy. ABSTRACT: Women with polycystic ovary syndrome (PCOS) commonly suffer from miscarriage, but the underlying mechanism of PCOS-induced fetal loss during pregnancy remains obscure and specific therapies are lacking. We used pregnant rats treated with 5α-dihydrotestosterone (DHT) and insulin to investigate the impact of hyperandrogenism and insulin resistance on fetal survival and to determine the molecular link between PCOS conditions and placental dysfunction during pregnancy. Our study shows that pregnant rats chronically treated with a combination of DHT and insulin exhibited endocrine aberrations such as hyperandrogenism and insulin resistance that are strikingly similar to those in pregnant PCOS patients. Of pathophysiological significance, DHT+insulin-treated pregnant rats had greater fetal loss and subsequently decreased litter sizes compared to normal pregnant rats. This negative effect was accompanied by impaired trophoblast differentiation, increased glycogen accumulation, and decreased angiogenesis in the placenta. Mechanistically, we report that over-production of reactive oxygen species (ROS) in the placenta, mitochondrial dysfunction, and disturbed superoxide dismutase 1 (SOD1) and Keap1/Nrf2 antioxidant responses constitute important contributors to fetal loss in DHT+insulin-treated pregnant rats. Many of the molecular pathways leading to placental abnormalities and fetal loss in DHT+insulin treatment were also seen in pregnant rats treated with DHT alone, whereas pregnant rats treated with insulin alone often exerted distinct effects on placental gene expression compared to insulin treatment in combination with DHT. We also found that treatment with the antioxidant N-acetylcysteine (NAC) improved fetal survival in DHT+insulin-treated pregnant rats, an effect related to changes in Keap1/Nrf2 and nuclear factor-κB signalling. However, NAC administration resulted in fetal loss in normal pregnant rats, most likely due to PCOS-like endocrine abnormality induced by the treatment. Our results suggest that the deleterious effects of hyperandrogenism and insulin resistance on fetal survival are related to a constellation of mitochondria-ROS-SOD1/Nrf2 changes in the placenta. Our findings also suggest that physiological levels of ROS are required for normal placental formation and fetal survival during pregnancy.


Assuntos
Aborto Espontâneo/metabolismo , Hiperandrogenismo/complicações , Mitocôndrias/metabolismo , Síndrome do Ovário Policístico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trofoblastos/metabolismo , Aborto Espontâneo/etiologia , Aborto Espontâneo/fisiopatologia , Animais , Di-Hidrotestosterona/toxicidade , Feminino , Glicogênio/metabolismo , Resistência à Insulina , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Mitocôndrias/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Gravidez , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase-1/metabolismo , Trofoblastos/patologia
17.
J Card Surg ; 34(5): 356-358, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30868644

RESUMO

Primary cardiac neoplasms are rare, cardiac hemangiomas are even rarer, and a mixed thrombus followed by a primary cardiac hemangioma is exceptionally rare epidemiology. Here, we report the case of a man with a right atrium mixed-thrombus surgical history who went on to develop a cardiac hemangioma.


Assuntos
Cardiopatias/complicações , Neoplasias Cardíacas/etiologia , Neoplasias Cardíacas/cirurgia , Hemangioma/etiologia , Hemangioma/cirurgia , Trombose/complicações , Idoso , Ecocardiografia , Átrios do Coração , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Hemangioma/diagnóstico por imagem , Hemangioma/patologia , Humanos , Masculino , Resultado do Tratamento
18.
J Card Surg ; 34(4): 167-169, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30834563

RESUMO

Functional tricuspid regurgitation (FTR) is the most common of all tricuspid dysfunctions. Ring annuloplasty is an effective treatment strategy for FTR. Currently, the most commonly used suture method for tricuspid ring annuloplasty is the interrupted U-shaped suture method. However, when tricuspid annuli are grossly dilated (septal segments > 60 mm), interrupted sutures are insufficient in avoiding the folding over of the annulus or the tearing of sutures. Therefore, we recommend a new band suture technique; namely, the three-suture junctional continuous suture band annuloplasty technique.


Assuntos
Anuloplastia da Valva Cardíaca/métodos , Técnicas de Sutura , Insuficiência da Valva Tricúspide/patologia , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/patologia , Valva Tricúspide/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
19.
Int J Mol Sci ; 20(2)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30669342

RESUMO

Adenosine deaminases acting on RNA (ADAR) are enzymes that regulate RNA metabolism through post-transcriptional mechanisms. ADAR1 is involved in a variety of pathological conditions including inflammation, cancer, and the host defense against viral infections. However, the role of ADAR1p150 in vascular disease remains unclear. In this study, we examined the expression of ADAR1p150 and its role in viral myocarditis (VMC) in a mouse model. VMC mouse cardiomyocytes showed significantly higher expression of ADAR1p150 compared to the control samples. Coimmunoprecipitation verified that ADAR1p150 forms a complex with Dicer in VMC. miRNA-222, which is involved in many cardiac diseases, is highly expressed in cardiomyocytes in VMC. In addition, the expression of miRNA-222 was promoted by ADAR1p150/Dicer. Among the target genes of miRNA-222, the expression of phosphatase-and-tensin (PTEN) protein was significantly reduced in VMC. By using a bioinformatics tool, we found a potential binding site of miRNA-222 on the PTEN gene's 3'-UTR, suggesting that miRNA-222 might play a regulatory role. In cultured cells, miR-222 suppressed PTEN expression. Our findings suggest that ADAR1p150 plays a key role in complexing with Dicer and promoting the expression of miRNA-222, the latter of which suppresses the expression of the target gene PTEN during VMC. Our work reveals a previously unknown role of ADAR1p150 in gene expression in VMC.


Assuntos
Adenosina Desaminase/metabolismo , Infecções por Coxsackievirus/complicações , Enterovirus Humano B , MicroRNAs/genética , Miocardite/etiologia , Miocardite/metabolismo , PTEN Fosfo-Hidrolase/genética , Ribonuclease III/metabolismo , Animais , Sobrevivência Celular/genética , Células Cultivadas , Infecções por Coxsackievirus/patologia , Infecções por Coxsackievirus/virologia , Modelos Animais de Doenças , Enterovirus Humano B/fisiologia , Expressão Gênica , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Imuno-Histoquímica , Masculino , Camundongos , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/virologia , Ligação Proteica , Interferência de RNA
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