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1.
NAR Cancer ; 6(2): zcae016, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38596431

RESUMO

With its ligand estrogen, the estrogen receptor (ER) initiates a global transcriptional program, promoting cell growth. This process involves topoisomerase 2 (TOP2), a key protein in resolving topological issues during transcription by cleaving a DNA duplex, passing another duplex through the break, and repairing the break. Recent studies revealed the involvement of various DNA repair proteins in the repair of TOP2-induced breaks, suggesting potential alternative repair pathways in cases where TOP2 is halted after cleavage. However, the contribution of these proteins in ER-induced transcriptional regulation remains unclear. We investigated the role of tyrosyl-DNA phosphodiesterase 2 (TDP2), an enzyme for the removal of halted TOP2 from the DNA ends, in the estrogen-induced transcriptome using both targeted and global transcription analyses. MYC activation by estrogen, a TOP2-dependent and transient event, became prolonged in the absence of TDP2 in both TDP2-deficient cells and mice. Bulk and single-cell RNA-seq analyses defined MYC and CCND1 as oncogenes whose estrogen response is tightly regulated by TDP2. These results suggest that TDP2 may inherently participate in the repair of estrogen-induced breaks at specific genomic loci, exerting precise control over oncogenic gene expression.

2.
Oper Neurosurg (Hagerstown) ; 26(1): 54-63, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37747348

RESUMO

BACKGROUND AND OBJECTIVES: The frontal sinus (FS) drainage pathway (FSDP) may be a conduit for cerebrospinal fluid leakage after frontobasal craniotomy. In this cadaveric study, we aimed to evaluate the anatomy of the FSDP. METHODS: The FSs and FSDPs of 247 cadavers were investigated. We counted the number of FSs and FSDPs in each half-head, verified the presence of a narrowing section in each FSDP, and evaluated the depth, shape, and size of each narrowing FSDP section. RESULTS: We investigated 494 sides and 472 FSDPs of 247 cadavers. FSs were unilaterally undeveloped in 13 of 247 cadavers (5.3%) and bilaterally in 8 (3.2%). FSs were unilaterally duplicated in 7 of 247 cadavers (2.8%), and no FSs were bilaterally duplicated or triplicated. No FSs had 2 or more FSDPs, and all 472 investigated FSDPs were invariably narrowed at various depths. The narrowing FSDP sections were elliptical (78.6%), circular (18.1%), triangular (1.8%), or crescent-shaped (1.4%) and of varying thickness and orientation. Although FSDPs were asymmetric in 92.2% of cadavers and narrowing FSDP sections were located deep (8.9 ± 4.4 mm from the anterior skull base), the narrowing FSDP sections were typically small (area: 5.9 ± 3.3 mm 2 ) or thin (short diameter: 2.1 ± 0.7 mm). CONCLUSION: Each FS had only one FSDP, all FSDPs were invariably narrowed at various depths, and the narrowing FSDP sections were sufficiently small or thin to allow local closure, facilitating prevention of cerebrospinal fluid leakage after frontobasal craniotomy.


Assuntos
Seio Frontal , Humanos , Seio Frontal/cirurgia , Vazamento de Líquido Cefalorraquidiano/cirurgia , Craniotomia/efeitos adversos , Drenagem , Cadáver
3.
Am J Disaster Med ; 18(1): 17-30, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37970696

RESUMO

OBJECTIVE: We aimed to clarify the characteristics of patients consulted by the medical staff with emergency medicine (EM) physicians after vaccination and EM physicians transferred to an outside hospital. DESIGN: The Japanese Self-Defense Force established a large-scale coronavirus disease 2019 (COVID-19) vaccination center. Overall, 1,306,928 citizens received the Moderna vaccine, which targeted the first and second vaccinations between May 24, 2021 and November 30, 2021. EM physicians were always available in the emergency room (ER). The medical staff could consult the patients with EM physicians; however, the criteria were ambiguous. We conducted signal detection analysis on the patients who experienced adverse events to detect characteristics. RESULTS: Of the 3,312 patients experienced adverse events after vaccination, the medical staff consulted 344 with EM physicians. The patients whose respiratory rate and systolic blood pressure (BP) were more than 18 per minute and 162 mmHg, respectively, were considerably consulted. In addition, the patients whose systolic BP was more than 186.5 mmHg were transferred to an outside hospital. No patients were seriously ill or died after being transferred to an outside hospital. CONCLUSIONS: The medical staff consulted the patients with a high respiratory rate or BP with EM physicians. In addition to BP, the respiratory rate would also be necessary as a finding that suggests a patient's severity after vaccination. Therefore, it appears safer that EM physicians are always available to ensure the recipients' safety when running a new large-scale vaccination center against unknown diseases, such as COVID-19.


Assuntos
COVID-19 , Medicina de Emergência , Médicos , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Vacinação , Estudos Prospectivos
4.
JACC Heart Fail ; 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37930291

RESUMO

BACKGROUND: Reliable predictors of treatment efficacy in heart failure have been long awaited. DNA damage has been implicated as a cause of heart failure. OBJECTIVES: The purpose of this study was to investigate the association of DNA damage in myocardial tissue with treatment response and prognosis of heart failure. METHODS: The authors performed immunostaining of DNA damage markers poly(ADP-ribose) (PAR) and γ-H2A.X in endomyocardial biopsy specimens from 175 patients with heart failure with reduced ejection fraction (HFrEF) of various underlying etiologies. They calculated the percentage of nuclei positive for each DNA damage marker (%PAR and %γ-H2A.X). The primary outcome was left ventricular reverse remodeling (LVRR) at 1 year, and the secondary outcome was a composite of cardiovascular death, heart transplantation, and ventricular assist device implantation. RESULTS: Patients who did not achieve LVRR after the optimization of medical therapies presented with significantly higher %PAR and %γ-H2A.X. The ROC analysis demonstrated good performance of both %PAR and %γ-H2A.X for predicting LVRR (AUCs: 0.867 and 0.855, respectively). There was a negative correlation between the mean proportion of DNA damage marker-positive nuclei and the probability of LVRR across different underlying diseases. In addition, patients with higher %PAR or %γ-H2A.X had more long-term clinical events (PAR HR: 1.63 [95% CI: 1.31-2.01; P < 0.001]; γ-H2A.X HR: 1.48 [95% CI: 1.27-1.72; P < 0.001]). CONCLUSIONS: DNA damage determines the consequences of human heart failure. Assessment of DNA damage is useful to predict treatment efficacy and prognosis of heart failure patients with various underlying etiologies.

5.
Front Neurol ; 14: 1269400, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869149

RESUMO

Introduction: This study aimed to examine the effect of newly developed scissors-attached micro-forceps in superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD). Materials and methods: Of 179 consecutive STA-MCA anastomoses on 95 hemispheres of 71 MMD patients at the University of Fukui Hospital between 2009 and 2023, 49 anastomoses on 26 hemispheres of 21 patients were enrolled in this retrospective cohort clinical trial intraoperative indocyanine green video-angiography did not demonstrate bypass patency in three anastomoses in two patients who were excluded. Twenty-one anastomosis in 19 hemispheres of 16 patients were performed using the conventional micro-forceps (conventional group, CG), and 25 anastomoses in 22 hemispheres of 19 patients were performed using scissors-attached micro-forceps (scissors group, SG). A small infarction near the anastomotic site detected using postoperative diffusion-weighted imaging was defined as anastomotic site infarction (ASI). Factors affecting the occurrence of ASI were examined by univariate, logistic regression, and receiver operating curve (ROC) analysis. Results: There were no significant differences in clinical parameters such as age, sex, number of sacrificed branches, number of sacrificed large branches, and number of sutures between the CG and SG. However, the clamp time and occurrence of ASI were significantly lower in the SG than in the CG. Logistic regression analysis revealed that the clamp time was the only significant factor predicting the occurrence of ASI. A receiver operating curve analysis also revealed that the clamp time significantly predicted the occurrence of ASI (area under the curve, 0.875; cutoff value, 33.2 min). Conclusion: The newly developed scissors-attached micro-forceps could significantly reduce the clamp time and occurrence of ASI in STA-MCA anastomosis for MMD.

6.
Front Physiol ; 14: 1220058, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664438

RESUMO

Hibernation is a unique physiological phenomenon allowing extreme hypothermia in endothermic mammals. Hypometabolism and hypothermia tolerance in hibernating animals have been investigated with particular interest; recently, studies of cultured cells and manipulation of the nervous system have made it possible to reproduce physiological states related to hypothermia induction. However, much remains unknown about the periodic regulation of hibernation. In particular, the physiological mechanisms facilitating the switch from an active state to a hibernation period, including behavioral changes and the acquisition of hypothermia tolerance remain to be elucidated. AMPK is a protein known to play a central role not only in feeding behavior but also in metabolic regulation in response to starvation. Our previous research has revealed that chipmunks activate AMPK in the brain during hibernation. However, whether AMPK is activated during winter in non-hibernating animals is unknown. Previous comparative studies between hibernating and non-hibernating animals have often been conducted between different species, consequently it has been impossible to account for the effects of phylogenetic differences. Our long-term monitoring of siberian chipmunks, has revealed intraspecific variation between those individuals that hibernate annually and those that never become hypothermic. Apparent differences were found between hibernating and non-hibernating types with seasonal changes in lifespan and blood HP levels. By comparing seasonal changes in AMPK activity between these polymorphisms, we clarified the relationship between hibernation and AMPK regulation. In hibernating types, phosphorylation of p-AMPK and p-ACC was enhanced throughout the brain during hibernation, indicating that AMPK-mediated metabolic regulation is activated. In non-hibernating types, AMPK and ACC were not seasonally activated. In addition, AMPK activation in the hypothalamus had already begun during high Tb before hibernation. Changes in AMPK activity in the brain during hibernation may be driven by circannual rhythms, suggesting a hibernation-regulatory mechanism involving AMPK activation independent of Tb. The differences in brain AMPK regulation between hibernators and non-hibernators revealed in this study were based on a single species thus did not involve phylogenetic differences, thereby supporting the importance of brain temperature-independent AMPK activation in regulating seasonal metabolism in hibernating animals.

7.
Materials (Basel) ; 16(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37687665

RESUMO

Our research aims to investigate the fabrication of additively manufactured (AMed) Ti-6Al-4V samples under reduced power with the addition of TiC heterogeneous nucleation site particles. For this aim, Ti-6Al-4V samples are fabricated with and without TiC heterogeneous nucleation site particles using an EOS M 290 machine under optimal parameters and reduced power conditions. The microstructure and tensile behavior of the produced samples were studied. In addition, a single-track test was performed to obtain a good understanding of the suppression of gas pores and balling formation with the addition of TiC heterogeneous nucleation site particles. It was found that the formation of gas pores and balling was suppressed with the addition of heterogeneous nucleation site particles within the metallic powder.

8.
NMC Case Rep J ; 10: 227-233, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37621749

RESUMO

A 47-year-old man presented with sudden-onset headache and Fisher group 3 subarachnoid hemorrhage. The World Federation of Neurological Surgeons grade was II. Digital subtraction angiography (DSA) only showed a vessel wall irregularity in the A1 segment of the right anterior cerebral artery (ACA), but an obvious bleeding source was not detected. Repeat angiography showed a tiny aneurysmal dilatation in the A1 segment with an intimal flap. The aneurysm enlarged on subsequent angiograms. Dissecting aneurysm was diagnosed, and the patient underwent internal trapping of the A1 segment to prevent rerupture. Postoperative DSA showed complete obliteration of the dissected segment. Magnetic resonance imaging showed a clinically silent cerebral infarction in the territory of the A1 segment perforators. Parent vessel occlusion for a dissected A1 segment can be effective, provided that sufficient collateral blood flow from the contralateral ACA is observed. We recommend endovascular trapping in this setting and hope that fellow clinicians select this approach for this rare pathology.

9.
J Card Fail ; 29(6): 931-938, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37321698

RESUMO

Despite decades of intensive research and therapeutic development, heart failure remains a leading cause of death worldwide. However, recent advances in several basic and translational research fields, such as genomic analysis and single-cell analysis, have increased the possibility of developing novel diagnostic approaches to heart failure. Most cardiovascular diseases that predispose individuals to heart failure are caused by genetic and environmental factors. It follows that genomic analysis can contribute to the diagnosis and prognostic stratification of patients with heart failure. In addition, single-cell analysis has shown great potential for unveiling the pathogenesis and/or pathophysiology and for discovering novel therapeutic targets for heart failure. Here, we summarize the recent advances in translational research on heart failure in Japan, based mainly on our studies.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/genética , Pesquisa Translacional Biomédica , Japão/epidemiologia , Prognóstico
10.
Commun Biol ; 6(1): 666, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37353597

RESUMO

Activation of the cholinergic anti-inflammatory pathway (CAP) via vagus nerve stimulation has been shown to improve acute kidney injury in rodent models. While alpha 7 nicotinic acetylcholine receptor (α7nAChR) positive macrophages are thought to play a crucial role in this pathway, their in vivo significance has not been fully understood. In this study, we used macrophage-specific α7nAChR-deficient mice to confirm the direct activation of α7nAChRs in macrophages. Our findings indicate that the administration of GTS-21, an α7nAChR-specific agonist, protects injured kidneys in wild-type mice but not in macrophage-specific α7nAChR-deficient mice. To investigate the signal changes or cell reconstructions induced by α7nAChR activation in splenocytes, we conducted single-cell RNA-sequencing of the spleen. Ligand-receptor analysis revealed an increase in macrophage-macrophage interactions. Using macrophage-derived cell lines, we demonstrated that GTS-21 increases cell contact, and that the contact between macrophages receiving α7nAChR signals leads to a reduction in TNF-α. Our results suggest that α7nAChR signaling increases macrophage-macrophage interactions in the spleen and has a protective effect on the kidneys.


Assuntos
Receptores Nicotínicos , Animais , Camundongos , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/agonistas , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Macrófagos/metabolismo , Anti-Inflamatórios/metabolismo , Comunicação Celular
11.
J Stroke Cerebrovasc Dis ; 32(8): 107173, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37186969

RESUMO

BACKGROUND: To examine the reasonable duration of continuous electrocardiographic monitoring (CEM) to detect AF at acute ischemic stroke. MATERIALS AND METHOD: 811 consecutive patients admitted to Tsuruga Municipal Hospital by acute ischemic stroke between April 2013 and December 2021 were enrolled in this study. Excluding 78 patients, 733 patients were analyzed by cluster analysis with SurvCART algorithm, followed by Kaplan-Meier analysis. RESULTS: The analysis provided step graphs for 8 subgroups. The duration of CEM to achieve the sensitivity of 0.8, 0.9, and 0.95 in each could be calculated. The duration of CEM to achieve the sensitivity of 0.8 are 18 days in female patients with heart failure (HF) (subgroup 1), 24 days in male patients with HF (subgroup 2), 22 days in patients without HF with arterial occlusion and pulse rate (PR) more than 91 (subgroup 3), 24 days in patients without HF with occlusion with PR less than 91 (subgroup 4), 18 days in patients without HF without occlusion with lacuna (subgroup 5), 26 days in patients without HF, occlusion, and lacuna, with arterial stenosis (subgroup 6), 15 days in patients without HF, occlusion, lacuna, and stenosis with BMI more than 21%(subgroup 7), and 44 days in patients without HF, occlusion, lacuna, stenosis and with BMI less than 21% (subgroup 8). CONCLUSIONS: Duration of CEM with the sensitivity of 0.8, 0.9, and 0.95 could be determined by presence of HF, female sex, arterial occlusion, PR more than 91/minute, presence of lacuna, presence of stenosis, and BMI more than 21%. (250).


Assuntos
Arteriopatias Oclusivas , Fibrilação Atrial , Insuficiência Cardíaca , AVC Isquêmico , Humanos , Feminino , Masculino , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Constrição Patológica , Frequência Cardíaca , Insuficiência Cardíaca/diagnóstico
12.
Sci Adv ; 9(15): eade7047, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37058558

RESUMO

Mutations in the LMNA gene encoding Lamin A and C (Lamin A/C), major components of the nuclear lamina, cause laminopathies including dilated cardiomyopathy (DCM), but the underlying molecular mechanisms have not been fully elucidated. Here, by leveraging single-cell RNA sequencing (RNA-seq), assay for transposase-accessible chromatin using sequencing (ATAC-seq), protein array, and electron microscopy analysis, we show that insufficient structural maturation of cardiomyocytes owing to trapping of transcription factor TEA domain transcription factor 1 (TEAD1) by mutant Lamin A/C at the nuclear membrane underlies the pathogenesis of Q353R-LMNA-related DCM. Inhibition of the Hippo pathway rescued the dysregulation of cardiac developmental genes by TEAD1 in LMNA mutant cardiomyocytes. Single-cell RNA-seq of cardiac tissues from patients with DCM with the LMNA mutation confirmed the dysregulated expression of TEAD1 target genes. Our results propose an intervention for transcriptional dysregulation as a potential treatment of LMNA-related DCM.


Assuntos
Cardiomiopatia Dilatada , Humanos , Cardiomiopatia Dilatada/metabolismo , Lamina Tipo A/genética , Miócitos Cardíacos/metabolismo , Mutação , Fatores de Transcrição de Domínio TEA
14.
Science ; 379(6632): 586-591, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36758070

RESUMO

Orthomyxo- and bunyaviruses steal the 5' cap portion of host RNAs to prime their own transcription in a process called "cap snatching." We report that RNA modification of the cap portion by host 2'-O-ribose methyltransferase 1 (MTr1) is essential for the initiation of influenza A and B virus replication, but not for other cap-snatching viruses. We identified with in silico compound screening and functional analysis a derivative of a natural product from Streptomyces, called trifluoromethyl-tubercidin (TFMT), that inhibits MTr1 through interaction at its S-adenosyl-l-methionine binding pocket to restrict influenza virus replication. Mechanistically, TFMT impairs the association of host cap RNAs with the viral polymerase basic protein 2 subunit in human lung explants and in vivo in mice. TFMT acts synergistically with approved anti-influenza drugs.


Assuntos
Antivirais , Produtos Biológicos , Inibidores Enzimáticos , Metiltransferases , Capuzes de RNA , Tubercidina , Replicação Viral , Animais , Humanos , Camundongos , Capuzes de RNA/metabolismo , RNA Mensageiro/metabolismo , RNA Viral/biossíntese , Replicação Viral/efeitos dos fármacos , /efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Antivirais/química , Antivirais/farmacologia , Tubercidina/análogos & derivados , Tubercidina/farmacologia , Metiltransferases/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Streptomyces/química , Simulação por Computador , Células A549
15.
Cell Rep ; 42(1): 111909, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36640339

RESUMO

ATM gene mutation carriers are predisposed to estrogen-receptor-positive breast cancer (BC). ATM prevents BC oncogenesis by activating p53 in every cell; however, much remains unknown about tissue-specific oncogenesis after ATM loss. Here, we report that ATM controls the early transcriptional response to estrogens. This response depends on topoisomerase II (TOP2), which generates TOP2-DNA double-strand break (DSB) complexes and rejoins the breaks. When TOP2-mediated ligation fails, ATM facilitates DSB repair. After estrogen exposure, TOP2-dependent DSBs arise at the c-MYC enhancer in human BC cells, and their defective repair changes the activation profile of enhancers and induces the overexpression of many genes, including the c-MYC oncogene. CRISPR/Cas9 cleavage at the enhancer also causes c-MYC overexpression, indicating that this DSB causes c-MYC overexpression. Estrogen treatment induced c-Myc protein overexpression in mammary epithelial cells of ATM-deficient mice. In conclusion, ATM suppresses the c-Myc-driven proliferative effects of estrogens, possibly explaining such tissue-specific oncogenesis.


Assuntos
Quebras de DNA de Cadeia Dupla , Genes myc , Humanos , Camundongos , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Reparo do DNA , Estrogênios/farmacologia , Epitélio/metabolismo , Carcinogênese/genética , Proteínas de Ciclo Celular/metabolismo
16.
Genes Cells ; 28(1): 53-67, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36415926

RESUMO

Steroid hormones induce the transcription of target genes by activating nuclear receptors. Early transcriptional response to various stimuli, including hormones, involves the active catalysis of topoisomerase II (TOP2) at transcription regulatory sequences. TOP2 untangles DNAs by transiently generating double-strand breaks (DSBs), where TOP2 covalently binds to DSB ends. When TOP2 fails to rejoin, called "abortive" catalysis, the resulting DSBs are repaired by tyrosyl-DNA phosphodiesterase 2 (TDP2) and non-homologous end-joining (NHEJ). A steroid, cortisol, is the most important glucocorticoid, and dexamethasone (Dex), a synthetic glucocorticoid, is widely used for suppressing inflammation in clinics. We here revealed that clinically relevant concentrations of Dex and physiological concentrations of cortisol efficiently induce DSBs in G1 phase cells deficient in TDP2 and NHEJ. The DSB induction depends on glucocorticoid receptor (GR) and TOP2. Considering the specific role of TDP2 in removing TOP2 adducts from DSB ends, induced DSBs most likely represent stalled TOP2-DSB complexes. Inhibition of RNA polymerase II suppressed the DSBs formation only modestly in the G1 phase. We propose that cortisol and Dex frequently generate DSBs through the abortive catalysis of TOP2 at transcriptional regulatory sequences, including promoters or enhancers, where active TOP2 catalysis occurs during early transcriptional response.


Assuntos
Quebras de DNA de Cadeia Dupla , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glucocorticoides/farmacologia , Reparo do DNA , Proteínas Nucleares/metabolismo , Hidrocortisona/farmacologia , Diester Fosfórico Hidrolases/genética , Diester Fosfórico Hidrolases/metabolismo , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , DNA/genética
17.
JMA J ; 5(4): 399-406, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36407067

RESUMO

Heart failure (HF) is a leading cause of death worldwide. In Japan, the number of HF patients has increased with its aging population, resulting in "HF pandemic." HF is the final stage of various cardiovascular diseases, including valvular heart disease, ischemic heart disease, atrial fibrillation, and hypertension. Cardiac hypertrophy is a compensatory response to increased workload and maintains cardiac function. Pressure overload due to mechanical stress causes cardiac hypertrophy, whereas continuous cardiac stress reduces wall thickness and consequently causes HF. Understanding the molecular mechanisms underlying this process is crucial to elucidate HF pathophysiology. We demonstrated that ischemia and DNA damage are important in the progression of hypertrophy to HF. Genetic mutations associated with cardiomyopathy and prognosis has been identified. To realize precision medicines for HF, the underlying molecular mechanisms need to be elucidated. In this review, we introduce new paradigms for understanding HF pathophysiology discovered through basic research.

18.
Nat Commun ; 13(1): 5117, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071032

RESUMO

Although inflammation plays critical roles in the development of atherosclerosis, its regulatory mechanisms remain incompletely understood. Perivascular adipose tissue (PVAT) has been reported to undergo inflammatory changes in response to vascular injury. Here, we show that vascular injury induces the beiging (brown adipose tissue-like phenotype change) of PVAT, which fine-tunes inflammatory response and thus vascular remodeling as a protective mechanism. In a mouse model of endovascular injury, macrophages accumulate in PVAT, causing beiging phenotype change. Inhibition of PVAT beiging by genetically silencing PRDM16, a key regulator to beiging, exacerbates inflammation and vascular remodeling following injury. Conversely, activation of PVAT beiging attenuates inflammation and pathological vascular remodeling. Single-cell RNA sequencing reveals that beige adipocytes abundantly express neuregulin 4 (Nrg4) which critically regulate alternative macrophage activation. Importantly, significant beiging is observed in the diseased aortic PVAT in patients with acute aortic dissection. Taken together, vascular injury induces the beiging of adjacent PVAT with macrophage accumulation, where NRG4 secreted from the beige PVAT facilitates alternative activation of macrophages, leading to the resolution of vascular inflammation. Our study demonstrates the pivotal roles of PVAT in vascular inflammation and remodeling and will open a new avenue for treating atherosclerosis.


Assuntos
Aterosclerose , Lesões do Sistema Vascular , Tecido Adiposo Marrom/patologia , Animais , Aterosclerose/genética , Aterosclerose/patologia , Inflamação/patologia , Camundongos , Remodelação Vascular , Lesões do Sistema Vascular/patologia
19.
EMBO J ; 41(17): e111608, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35833542

RESUMO

The SARS-CoV-2 infection cycle is a multistage process that relies on functional interactions between the host and the pathogen. Here, we repurposed antiviral drugs against both viral and host enzymes to pharmaceutically block methylation of the viral RNA 2'-O-ribose cap needed for viral immune escape. We find that the host cap 2'-O-ribose methyltransferase MTr1 can compensate for loss of viral NSP16 methyltransferase in facilitating virus replication. Concomitant inhibition of MTr1 and NSP16 efficiently suppresses SARS-CoV-2 replication. Using in silico target-based drug screening, we identify a bispecific MTr1/NSP16 inhibitor with anti-SARS-CoV-2 activity in vitro and in vivo but with unfavorable side effects. We further show antiviral activity of inhibitors that target independent stages of the host SAM cycle providing the methyltransferase co-substrate. In particular, the adenosylhomocysteinase (AHCY) inhibitor DZNep is antiviral in in vitro, in ex vivo, and in a mouse infection model and synergizes with existing COVID-19 treatments. Moreover, DZNep exhibits a strong immunomodulatory effect curbing infection-induced hyperinflammation and reduces lung fibrosis markers ex vivo. Thus, multispecific and metabolic MTase inhibitors constitute yet unexplored treatment options against COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Animais , Antivirais/farmacologia , Inflamação/tratamento farmacológico , Metiltransferases/metabolismo , Camundongos , Capuzes de RNA/metabolismo , RNA Viral/genética , Ribose , Proteínas não Estruturais Virais/genética
20.
Nat Commun ; 13(1): 3275, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672400

RESUMO

Tissue fibrosis and organ dysfunction are hallmarks of age-related diseases including heart failure, but it remains elusive whether there is a common pathway to induce both events. Through single-cell RNA-seq, spatial transcriptomics, and genetic perturbation, we elucidate that high-temperature requirement A serine peptidase 3 (Htra3) is a critical regulator of cardiac fibrosis and heart failure by maintaining the identity of quiescent cardiac fibroblasts through degrading transforming growth factor-ß (TGF-ß). Pressure overload downregulates expression of Htra3 in cardiac fibroblasts and activated TGF-ß signaling, which induces not only cardiac fibrosis but also heart failure through DNA damage accumulation and secretory phenotype induction in failing cardiomyocytes. Overexpression of Htra3 in the heart inhibits TGF-ß signaling and ameliorates cardiac dysfunction after pressure overload. Htra3-regulated induction of spatio-temporal cardiac fibrosis and cardiomyocyte secretory phenotype are observed specifically in infarct regions after myocardial infarction. Integrative analyses of single-cardiomyocyte transcriptome and plasma proteome in human reveal that IGFBP7, which is a cytokine downstream of TGF-ß and secreted from failing cardiomyocytes, is the most predictable marker of advanced heart failure. These findings highlight the roles of cardiac fibroblasts in regulating cardiomyocyte homeostasis and cardiac fibrosis through the Htra3-TGF-ß-IGFBP7 pathway, which would be a therapeutic target for heart failure.


Assuntos
Insuficiência Cardíaca , Fator de Crescimento Transformador beta , Fibroblastos/metabolismo , Fibrose , Insuficiência Cardíaca/metabolismo , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Fator de Crescimento Transformador beta/metabolismo
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