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1.
Mol Cell ; 67(5): 812-825.e5, 2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28826672

RESUMO

Delta-secretase, a lysosomal asparagine endopeptidase (AEP), simultaneously cleaves both APP and tau, controlling the onset of pathogenesis of Alzheimer's disease (AD). However, how this protease is post-translationally regulated remains unclear. Here we report that serine-arginine protein kinase 2 (SRPK2) phosphorylates delta-secretase and enhances its enzymatic activity. SRPK2 phosphorylates serine 226 on delta-secretase and accelerates its autocatalytic cleavage, leading to its cytoplasmic translocation and escalated enzymatic activities. Delta-secretase is highly phosphorylated in human AD brains, tightly correlated with SRPK2 activity. Overexpression of a phosphorylation mimetic (S226D) in young 3xTg mice strongly promotes APP and tau fragmentation and facilitates amyloid plaque deposits and neurofibrillary tangle (NFT) formation, resulting in cognitive impairment. Conversely, viral injection of the non-phosphorylatable mutant (S226A) into 5XFAD mice decreases APP and tau proteolytic cleavage, attenuates AD pathologies, and reverses cognitive defects. Our findings support that delta-secretase phosphorylation by SRPK2 plays a critical role in aggravating AD pathogenesis.


Assuntos
Doença de Alzheimer/enzimologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Encéfalo/enzimologia , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Secretases da Proteína Precursora do Amiloide/genética , Animais , Comportamento Animal , Encéfalo/patologia , Encéfalo/fisiopatologia , Cognição , Modelos Animais de Doenças , Predisposição Genética para Doença , Células HEK293 , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Fenótipo , Fosforilação , Placa Amiloide , Proteínas Serina-Treonina Quinases/genética , Transporte Proteico , Interferência de RNA , Serina , Especificidade por Substrato , Fatores de Tempo , Transfecção , Proteínas tau/genética , Proteínas tau/metabolismo
2.
J Am Chem Soc ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39302880

RESUMO

Acetylene hydrochlorination is a vital industrial process for the manufacture of vinyl chloride monomer (VCM). Current thermocatalytic acetylene hydrochlorination requires toxic mercury-based or costly noble metal-based catalysts, high temperatures (≥180 °C) and excessive gaseous HCl. Here, we report a room-temperature photocatalytic acetylene hydrochlorination strategy involving concurrent coupling of electron-driven proton reduction (*H) and hole-driven chloride oxidation (*Cl) on photocatalyst surfaces. Under simulated solar light illumination, the developed noble-metal-free g-C3N4/BiOCl photocatalysts show a considerably high VCM production rate of 1198.6 µmol g-1 h-1 and a high VCM selectivity of 95% in a 0.1 M HCl aqueous solution. Even in chloride-rich natural seawater and acidified natural seawater, the VCM production rates of g-C3N4/BiOCl photocatalysts are up to 170.3 µmol g-1 h-1 with a VCM selectivity of 80.4% and 1247.7 µmol g-1 h-1 with a VCM selectivity of 94.7%, respectively. Moreover, with sunlight irradiation and acidified natural seawater, the g-C3N4/BiOCl photocatalysts in a large-scale photosystem retain outstanding acetylene hydrochlorination performance over 10 days of operation. The radical scavenging, in situ photochemical Fourier transform infrared spectroscopy, theoretical simulations, and control experiments reveal that active *Cl and *H play key roles in photocatalytic acetylene hydrochlorination via a possible reaction pathway of C2H2 → *C2H2 → *C2H2Cl → *C2H3Cl → C2H3Cl. With respect to sustainability and low cost, this photocatalytic acetylene hydrochlorination offers excellent advantages over conventional thermocatalytic hydrochlorination technologies.

3.
J Am Chem Soc ; 146(27): 18556-18564, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38943576

RESUMO

Manipulating single electrons at the atomic scale is vital for mastering complex surface processes governed by the transfer of individual electrons. Polarons, composed of electrons stabilized by electron-phonon coupling, offer a pivotal medium for such manipulation. Here, using scanning tunneling microscopy and spectroscopy (STM/STS) and density functional theory (DFT) calculations, we report the identification and manipulation of a new type of polaron, dubbed van der Waals (vdW) polaron, within mono- to trilayer ultrathin films composed of Sb2O3 molecules that are bonded via vdW attractions. The Sb2O3 films were grown on a graphene-covered SiC(0001) substrate via molecular beam epitaxy. Unlike prior molecular polarons, STM imaging observed polarons at the interstitial sites of the molecular film, presenting unique electronic states and localized band bending. DFT calculations revealed the lowest conduction band as an intermolecular bonding state, capable of ensnaring an extra electron through locally diminished intermolecular distances, thereby forming an intermolecular vdW polaron. We also demonstrated the ability to generate, move, and erase such vdW polarons using an STM tip. Our work uncovers a new type of polaron stabilized by coupling with intermolecular vibrations where vdW interactions dominate, paving the way for designing atomic-scale electron transfer processes and enabling precise tailoring of electron-related properties and functionalities.

4.
J Am Chem Soc ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598684

RESUMO

Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces. Using scanning tunneling microscopy, we examine the reaction process at the single-molecular level, quantify the selectivity of the dehydrobrominative cross-coupling, and reveal the modulation of selectivity by substrate lattice-related catalytic activity or molecular assembly effect. Theoretical calculations indicate that the dehydrobrominative cross-coupling proceeds via regioselective C-H bond activation of debrominated TBPB and subsequent highly selective C-C coupling of the radical-based intermediates. The reaction kinetics plays an important role in the selectivity for the cross-coupling. This work not only expands the toolbox for chemical synthesis but also provides important mechanistic insights into the selectivity of coupling reactions on the surface.

5.
J Am Chem Soc ; 146(10): 6618-6627, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38349322

RESUMO

Single-crystal semiconductor-based photocatalysts exposing unique crystallographic facets show promising applications in energy and environmental technologies; however, crystal facet engineering through solid-state synthesis for photocatalytic overall water splitting is still challenging. Herein, we develop a novel crystal facet engineering strategy through solid-state recrystallization to synthesize uniform SrTiO3 single crystals exposing tailored {111} facets. The presynthesized low-crystalline SrTiO3 precursors enable the formation of well-defined single crystals through kinetically improved crystal structure transformation during solid-state recrystallization process. By employing subtle Al3+ ions as surface morphology modulators, the crystal surface orientation can be precisely tuned to a controlled percentage of {111} facets. The photocatalytic overall water splitting activity increases with the exposure percentage of {111} facets. Owing to the outstanding crystallinity and favorable anisotropic surface structure, the SrTiO3 single crystals with 36.6% of {111} facets lead to a 3-fold enhancement of photocatalytic hydrogen evolution rates up to 1.55 mmol·h-1 in a stoichiometric ratio of 2:1 than thermodynamically stable SrTiO3 enclosed with isotropic {100} facets.

6.
Int J Obes (Lond) ; 48(10): 1438-1446, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38926462

RESUMO

BACKGROUND: The obesity paradox has been reported among older adults. However, whether the favorable effect of obesity is dependent on metabolic status remains largely unknown. We aimed to explore the association of metabolic obesity phenotypes and their changes with all-cause mortality among the Chinese oldest-old population. METHODS: This prospective cohort study included 1207 Chinese oldest old (mean age: 91.8 years). Metabolic obesity phenotypes were determined by central obesity and metabolic status, and participants were classified into metabolically healthy obesity (MHO), metabolically unhealthy obesity (MUO), metabolically healthy non-obesity (MHN), and metabolically unhealthy non-obesity (MUN). The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were estimated by Cox regression models. RESULTS: During 5.3 years of follow-up, 640 deaths were documented. Compared with non-obesity, obesity was associated with a decreased mortality risk among participants with metabolically healthy (HR, 0.75; 95% CI, 0.63-0.91) while this association was insignificant among metabolically unhealthy. Compared to MHO, MHN (HR, 1.27; 95% CI, 1.06-1.53) and MUN (HR, 1.49; 95% CI, 1.10-2.02) were significantly associated with an increased mortality risk. Compared to those with stable MHO, those transited from MHO to MUO demonstrated a higher mortality risk (HR, 1.81; 95% CI, 1.06-3.11). CONCLUSIONS: MHO predicts better survival among the Chinese oldest-old population. These findings suggest that ensuring optimal management of metabolic health is beneficial and taking caution in weight loss based on the individual body weight for the metabolically healthy oldest-old adults.

7.
Plant Cell Environ ; 47(6): 2163-2177, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38481060

RESUMO

Copper (Cu) is an essential micronutrient for all living organisms but is also highly toxic in excess. Cellular homoeostasis of Cu is maintained by various transporters and metallochaperones. Here, we investigated the biological function of OsCOPT7, a member of the copper transporters (COPT) family, in Cu homoeostasis in rice. OsCOPT7 was mainly expressed in the roots and the expression was upregulated by Cu deficiency. OsCOPT7 was localized at the tonoplast and the endoplasmic reticulum. Knockout of OsCOPT7 increased Cu accumulation in the roots but decreased Cu concentrations in the shoots and grain. The knockout mutants contained higher concentrations of Cu in the roots cell sap but markedly lower concentrations of Cu in the xylem sap than wild-type plants. Seed setting and grain yield were reduced significantly in the knockout mutants grown in a low Cu soil. Knockout mutants were more tolerant to Cu toxicity. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that OsCOPT7 interacts physically with the rice Cu chaperone antioxidant protein 1 (OsATX1). Taken together, our results indicate that OsCOPT7 is a specific Cu transporter functioning to export Cu from the vacuoles and the ER and plays an important role in controlling the root-to-shoot Cu translocation in rice.


Assuntos
Cobre , Retículo Endoplasmático , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Transporte Biológico , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/genética , Cobre/metabolismo , Grão Comestível/metabolismo , Grão Comestível/genética , Retículo Endoplasmático/metabolismo , Técnicas de Inativação de Genes , Oryza/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Sementes/metabolismo , Sementes/genética , Vacúolos/metabolismo
8.
Cardiovasc Diabetol ; 23(1): 276, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068437

RESUMO

BACKGROUND: Atherogenic index of plasma (AIP), a marker of atherosclerosis and cardiovascular disease (CVD). However, few studies have investigated association between AIP and all-cause mortality and specific-mortality in the general population. METHODS: This study included data from 14,063 American adults. The exposure variable was the AIP, which was defined as log10 (triglycerides/high-density lipoprotein cholesterol). The outcome variables included all-cause mortality and specific-mortality. Survey-weighted cox regressions were performed to evaluate the relation between AIP and all-cause mortality and specific-mortality. Weighted restricted cubic spline was conducted to examin the non-linear relationship. RESULTS: During 10 years of follow-up, we documented 2,077, 262, 854, and 476 cases of all-cause mortality, diabetes mortality, CVD mortality and cancer mortality, respectively. After adjustment for potential confounders, we found that atherogenic index of plasma (AIP) was significantly associated with an increased risk of diabetes mortality when comparing the highest to the lowest quantile of AIP in female (p for trend = 0.001) or participants older than 65 years (p for trend = 0.002). AIP was not significantly associated with all-cause mortality, CVD mortality and cancer mortality (p > 0.05). Moreover, a non-linear association was observed between AIP and all-cause mortality in a U-shape (p for non-linear = 0.0011), while a linear relationship was observed with diabetes mortality and non-diabetes mortality (p for linear < 0.0001). CONCLUSIONS: In this study, there is a no significant association between high AIP levels and a high risk of all-cause and cardiovascular mortality. Besides, a higher AIP was significantly associated with an increased risk of diabetes mortality, which only found in women older than 65 years. AIP was associated with all-cause mortality in a U-shape. This association could be explained by the finding that higher AIP predicted a higher risk of death from diabetes, and that lower AIP predicted a higher risk of death from non-diabetes causes.


We used a large national database and a prospective cohort study with a long follow-up period. Higher AIP was significantly associated with an increased risk of diabetes mortality, only in women older than 65 years. There is a no significant association between high AIP levels and a high risk of all-cause and cardiovascular mortality. AIP was associated with all-cause mortality in a U-shape. This finding suggest that controlling AIP levels may have a positive effect on reducing diabetes mortality.


Assuntos
Aterosclerose , Biomarcadores , Causas de Morte , HDL-Colesterol , Diabetes Mellitus , Triglicerídeos , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Medição de Risco , Biomarcadores/sangue , Aterosclerose/mortalidade , Aterosclerose/sangue , Aterosclerose/diagnóstico , Fatores de Risco , Fatores de Tempo , Adulto , Diabetes Mellitus/mortalidade , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , HDL-Colesterol/sangue , Estados Unidos/epidemiologia , Triglicerídeos/sangue , Prognóstico , Neoplasias/mortalidade , Neoplasias/sangue , Neoplasias/diagnóstico , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico
9.
Chemistry ; : e202401763, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105366

RESUMO

Lipid droplets (LDs) are subcellular organelles that are dynamic and play a central role in energy homeostasis and lipid metabolism. They also contribute to the transport and maturation of cellular proteins and are closely associated with several diseases. The important role of the cellular microenvironment in maintaining cellular homeostasis. Changes in cell polarity, particularly in organelles, have been found to be strongly linked to inflammation, Alzheimer's disease, cancer, and other illnesses. It is essential to check the polarity of the LDs. A series of arylated naphthalimide derivatives were synthesized using the Suzuki reaction. Modification of synthesized aryl naphthalimides using oligomeric PEG based on intramolecular charge transfer (ICT) mechanism. A series of fluorescent probes were designed to target LDs and detect their polarity. Nap-TPA-PEG3 probe exhibited high sensitivity to polarity. The addition of oligomeric polyethylene glycol (PEG) to the probe not only significantly improved its solubility in water, but also effectively reduced its cytotoxicity. In addition, the probe exhibited excellent aggregation-induced luminescence (AIE) properties and solvent discolouration effects. Nap-TPA-PEG3 probe exhibited high Pearson correlation coefficient (0.957163) in lipid droplet co-localization in cells. Nap-TPA-PEG3 could be used as an effective hand tool to monitor cell polarity.

10.
J Nutr ; 154(4): 1262-1270, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38367806

RESUMO

BACKGROUND: The relationship between whole grain intake and chronic kidney disease (CKD) remains uncertain. OBJECTIVE: This study aimed to evaluate the association between whole grain intake and risk of CKD in Chinese adults. METHODS: The present cross-sectional study used data from the China Health and Nutrition Survey conducted in 2009. Whole grain intake was measured using 3 consecutive 24-h dietary recalls and a household food inventory. A multivariable logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of CKD. In addition, a restricted cubic spline was used to investigate the dose‒response relationship between whole grain and risk of CKD. RESULTS: A total of 6747 participants were included, 728 of whom had CKD. Compared with those in the lowest whole grain intake group, those in the higher grain intake group had an inverse association with risk of CKD (Q2: adjusted OR 0.70, 95% CI: 0.54, 0.89; Q3: adjusted OR 0.54, 95% CI: 0.42, 0.69; and Q4: adjusted OR 0.29, 95% CI: 0.21, 0.41). The association between whole grain intake and CKD seems to be stronger for individuals who were male (P for interaction = 0.008) or smokers (P for interaction = 0.013). In addition, the restricted cubic spline suggested an obvious L-shaped correlation. CONCLUSIONS: Increased whole grain intake was associated with a decreased risk of CKD in Chinese adults.


Assuntos
Insuficiência Renal Crônica , Grãos Integrais , Adulto , Humanos , Masculino , Feminino , Estudos Transversais , Insuficiência Renal Crônica/epidemiologia , Dieta , Inquéritos Nutricionais
11.
Brain Behav Immun ; 119: 56-83, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38555992

RESUMO

Decreased hippocampal tropomyosin receptor kinase B (TrkB) level is implicated in the pathophysiology of stress-induced mood disorder and cognitive decline. However, how TrkB is modified and mediates behavioral responses to chronic stress remains largely unknown. Here the effects and mechanisms of TrkB cleavage by asparagine endopeptidase (AEP) were examined on a preclinical murine model of chronic restraint stress (CRS)-induced depression. CRS activated IL-1ß-C/EBPß-AEP pathway in mice hippocampus, accompanied by elevated TrkB 1-486 fragment generated by AEP. Specifi.c overexpression or suppression of AEP-TrkB axis in hippocampal CaMKIIα-positive cells aggravated or relieved depressive-like behaviors, respectively. Mechanistically, in addition to facilitating AMPARs internalization, TrkB 1-486 interacted with peroxisome proliferator-activated receptor-δ (PPAR-δ) and sequestered it in cytoplasm, repressing PPAR-δ-mediated transactivation and mitochondrial function. Moreover, co-administration of 7,8-dihydroxyflavone and a peptide disrupting the binding of TrkB 1-486 with PPAR-δ attenuated depression-like symptoms not only in CRS animals, but also in Alzheimer's disease and aged mice. These findings reveal a novel role for TrkB cleavage in promoting depressive-like phenotype.


Assuntos
Depressão , Hipocampo , Estresse Psicológico , Animais , Hipocampo/metabolismo , Camundongos , Depressão/metabolismo , Masculino , Estresse Psicológico/metabolismo , Receptor trkB/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Comportamento Animal/fisiologia , Transdução de Sinais/fisiologia , Doença de Alzheimer/metabolismo , Glicoproteínas de Membrana/metabolismo
12.
Physiol Plant ; 176(2): e14280, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38644527

RESUMO

Inadequate reference databases in RNA-seq analysis can hinder data utilization and interpretation. In this study, we have successfully constructed a high-quality reference transcript dataset, ZjRTD1.0, for Zoysia japonica, a widely-used turfgrass with exceptional tolerance to various abiotic stress, including low temperatures and salinity. This dataset comprises 113,089 transcripts from 57,143 genes. BUSCO analysis demonstrates exceptional completeness (92.4%) in ZjRTD1.0, with reduced proportions of fragmented (3.3%) and missing (4.3%) orthologs compared to prior datasets. ZjRTD1.0 enables more precise analyses, including transcript quantification and alternative splicing assessments using public datasets, which identified a substantial number of differentially expressed transcripts (DETs) and differential alternative splicing (DAS) events, leading to several novel findings on Z. japonica's responses to abiotic stresses. First, spliceosome gene expression influenced alternative splicing significantly under abiotic stress, with a greater impact observed during low-temperature stress. Then, a significant positive correlation was found between the number of differentially expressed genes (DEGs) encoding protein kinases and the frequency of DAS events, suggesting the role of protein phosphorylation in regulating alternative splicing. Additionally, our results suggest possible involvement of serine/arginine-rich (SR) proteins and heterogeneous nuclear ribonucleoproteins (hnRNPs) in generating inclusion/exclusion isoforms under low-temperature stress. Furthermore, our investigation revealed a significantly enhanced overlap between DEGs and differentially alternatively spliced genes (DASGs) in response to low-temperature stress, suggesting a unique co-regulatory mechanism governing transcription and splicing in the context of low-temperature response. In conclusion, we have proven that ZjRTD1.0 will serve as a reliable and useful resource for future transcriptomic analyses in Z. japonica.


Assuntos
Processamento Alternativo , Temperatura Baixa , Poaceae , Processamento Alternativo/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poaceae/genética , Estresse Fisiológico/genética , Transcriptoma/genética
13.
Bioorg Med Chem ; 100: 117631, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38330848

RESUMO

Acute myeloid leukemia (AML) is the most common type of blood cancer and has been strongly correlated with the overexpression of Fms-like tyrosine kinase 3 (FLT3), a member of the class III receptor tyrosine kinase family. With the emergence of FLT3 internal tandem duplication alteration (ITD) and tyrosine kinase domain (TKD) mutations, the development of FLT3 small molecule inhibitors has become an effective medicinal chemistry strategy for AML. Herein, we have designed and synthesized two series of 1H-pyrrolo[2,3-b]pyridine derivatives CM1-CM24, as FLT3 inhibitors based on F14, which we previously reported, that can target the hydrophobic FLT3 back pocket. Among these derivates, CM5 showed significant inhibition of FLT3 and FLT3-ITD, with inhibitory percentages of 57.72 % and 53.77 % respectively at the concentration of 1 µΜ. Furthermore, CM5 demonstrated potent inhibition against FLT3-dependent human AML cell lines MOLM-13 and MV4-11 (both harboring FLT3-ITD mutant), with IC50 values of 0.75 µM and 0.64 µM respectively. In our cellular mechanistic studies, CM5 also effectively induces apoptosis by arresting cell cycle progression in the G0/G1 phase. In addition, the amide and urea linker function were discussed in detail based on computational simulations studies. CM5 will serve as a novel lead compound for further structural modification and development of FLT3 inhibitors specifically targeting AML with FLT3-ITD mutations.


Assuntos
Leucemia Mieloide Aguda , Tirosina Quinase 3 Semelhante a fms , Humanos , Apoptose , Linhagem Celular Tumoral , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Piridinas/farmacologia
14.
Eur J Nutr ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814365

RESUMO

IMPORTANCE: Epidemiological evidences regarding the association between whole grain intake and the risk of new-onset hypertension are still controversial. OBJECTIVE: We aimed to investigate the relationship between whole grain intake and new-onset hypertension and examine possible effect modifiers in the general population. METHODS: A total of 10,973 participants without hypertension from the China Health and Nutrition Survey were enrolled, with follow-up beginning in 1997 and ending in 2015. Whole grain intake was assessed by 3 consecutive 24-h dietary recalls combined with a household food inventory. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression model after adjusting for potential risk factors. RESULTS: During a median follow-up of 7.0 years, 3,733 participants developed new-onset hypertension. The adjusted HRs (95% CIs) were as follows: for quartile 2 (HR: 0.52; 95% CI: 0.47-0.57), quartile 3 (HR: 0.46; 95% CI: 0.42-0.51), and quartile 4 (HR: 0.35; 95% CI: 0.31-0.38), compared with quartile 1. Different types of whole grain types, including wheat (adjusted HR, 0.35; 95% CI, 0.32-0.39), maize (adjusted HR, 0.50; 95% CI, 0.42-0.59), and millet (adjusted HR, 0.38; 95% CI, 0.30-0.48), showed significant associations with a reduced risk of hypertension. The association between whole grain intake and new-onset hypertension was stronger in individuals with older age (P for interaction < 0.001) and higher BMI (P for interaction < 0.001). CONCLUSION: Higher consumption of whole grains was significantly associated with a lower risk of new-onset hypertension. This study provides further evidence supporting the importance of increasing whole grain intake for hypertension prevention among Chinese adults.

15.
Acta Pharmacol Sin ; 45(7): 1406-1424, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38589687

RESUMO

Acute kidney injury (AKI) is often accompanied by uremic encephalopathy resulting from accumulation of uremic toxins in brain possibly due to impaired blood-brain barrier (BBB) function. Anionic uremic toxins are substrates or inhibitors of organic anionic transporters (OATs). In this study we investigated the CNS behaviors and expression/function of BBB OAT3 in AKI rats and mice, which received intraperitoneal injection of cisplatin 8 and 20 mg/kg, respectively. We showed that cisplatin treatment significantly inhibited the expressions of OAT3, synaptophysin and microtubule-associated protein 2 (MAP2), impaired locomotor and exploration activities, and increased accumulation of uremic toxins in the brain of AKI rats and mice. In vitro studies showed that uremic toxins neither alter OAT3 expression in human cerebral microvascular endothelial cells, nor synaptophysin and MAP2 expressions in human neuroblastoma (SH-SY5Y) cells. In contrast, tumour necrosis factor alpha (TNFα) and the conditioned medium (CM) from RAW264.7 cells treated with indoxyl sulfate (IS) significantly impaired OAT3 expression. TNFα and CM from IS-treated BV-2 cells also inhibited synaptophysin and MAP2 expressions in SH-SY5Y cells. The alterations caused by TNFα and CMs in vitro, and by AKI and TNFα in vivo were abolished by infliximab, a monoclonal antibody designed to intercept and neutralize TNFα, suggesting that AKI impaired the expressions of OAT3, synaptophysin and MAP2 in the brain via IS-induced TNFα release from macrophages or microglia (termed as IS-TNFα axis). Treatment of mice with TNFα (0.5 mg·kg-1·d-1, i.p. for 3 days) significantly increased p-p65 expression and reduced the expressions of Nrf2 and HO-1. Inhibiting NF-κB pathway, silencing p65, or activating Nrf2 and HO-1 obviously attenuated TNFα-induced downregulation of OAT3, synaptophysin and MAP2 expressions. Significantly increased p-p65 and decreased Nrf2 and HO-1 protein levels were also detected in brain of AKI mice and rats. We conclude that AKI inhibits the expressions of OAT3, synaptophysin and MAP2 due to IS-induced TNFα release from macrophages or microglia. TNFα impairs the expressions of OAT3, synaptophysin and MAP2 partly via activating NF-κB pathway and inhibiting Nrf2-HO-1 pathway.


Assuntos
Injúria Renal Aguda , Cisplatino , Indicã , Fator de Necrose Tumoral alfa , Animais , Injúria Renal Aguda/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Humanos , Camundongos , Masculino , Células RAW 264.7 , Ratos , Camundongos Endogâmicos C57BL , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ratos Sprague-Dawley , Sinaptofisina/metabolismo , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Uremia/metabolismo , Uremia/complicações , Linhagem Celular Tumoral
16.
Acta Pharmacol Sin ; 45(9): 1793-1808, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38740904

RESUMO

The circadian clock is the inner rhythm of life activities and is controlled by a self-sustained and endogenous molecular clock, which maintains a ~ 24 h internal oscillation. As the core element of the circadian clock, BMAL1 is susceptible to degradation through the ubiquitin-proteasome system (UPS). Nevertheless, scant information is available regarding the UPS enzymes that intricately modulate both the stability and transcriptional activity of BMAL1, affecting the cellular circadian rhythm. In this work, we identify and validate UBR5 as a new E3 ubiquitin ligase that interacts with BMAL1 by using affinity purification, mass spectrometry, and biochemical experiments. UBR5 overexpression induced BMAL1 ubiquitination, leading to diminished stability and reduced protein level of BMAL1, thereby attenuating its transcriptional activity. Consistent with this, UBR5 knockdown increases the BMAL1 protein. Domain mapping discloses that the C-terminus of BMAL1 interacts with the N-terminal domains of UBR5. Similarly, cell-line-based experiments discover that HYD, the UBR5 homolog in Drosophila, could interact with and downregulate CYCLE, the BMAL1 homolog in Drosophila. PER2-luciferase bioluminescence real-time reporting assay in a mammalian cell line and behavioral experiments in Drosophila reveal that UBR5 or hyd knockdown significantly reduces the period of the circadian clock. Therefore, our work discovers a new ubiquitin ligase UBR5 that regulates BMAL1 stability and circadian rhythm and elucidates the underlying molecular mechanism. This work provides an additional layer of complexity to the regulatory network of the circadian clock at the post-translational modification level, offering potential insights into the modulation of the dysregulated circadian rhythm.


Assuntos
Fatores de Transcrição ARNTL , Ritmo Circadiano , Ubiquitina-Proteína Ligases , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Fatores de Transcrição ARNTL/metabolismo , Fatores de Transcrição ARNTL/genética , Animais , Humanos , Ritmo Circadiano/fisiologia , Células HEK293 , Proteólise , Relógios Circadianos/fisiologia , Proteínas Circadianas Period/metabolismo , Proteínas Circadianas Period/genética
17.
Dig Dis Sci ; 69(8): 2875-2882, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38879737

RESUMO

OBJECTIVE: Gastric cancer is a malignant tumor with high morbidity and mortality all around the world. Because of its poor prognosis and low survival rate, the treatment of gastric cancer has received extensive attention. Cinnamaldehyde (CA) is the main single active component of the Chinese herbal medicine cinnamon, which has a variety of pharmacological effects. The inhibitory effect of CA on the growth of some tumor cells has been proven, but its therapeutic effect on gastric cancer has rarely been reported. METHODS: Through network pharmacology, bioinformatics methods, and molecular docking technology, we predicted the interaction targets of CA and gastric cancer. Moreover, we found that apoptosis is an important mode of action of CA on gastric cancer cells. Subsequently, we validated it in gastric cancer cell lines cultured in vitro. RESULTS: The results showed that in the presence of CA, the Jak2/Stat3 pathway was inhibited, the ratio of Bcl-2/Bax decreased, and the apoptosis of gastric cancer cells was promoted in a concentration-dependent. CONCLUSION: In conclusion, CA can promote the apoptosis of gastric cancer cells by inhibiting the activity of the Jak2/Stat3 pathway, which may achieve the effect of treating gastric cancer.


Assuntos
Acroleína , Apoptose , Movimento Celular , Janus Quinase 2 , Fator de Transcrição STAT3 , Transdução de Sinais , Neoplasias Gástricas , Humanos , Acroleína/análogos & derivados , Acroleína/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Neoplasias Gástricas/metabolismo , Fator de Transcrição STAT3/metabolismo , Janus Quinase 2/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
18.
Nutr J ; 23(1): 91, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138490

RESUMO

BACKGROUND: Dietary diversity has been suggested as a potential preventive measure against frailty in older adults, but the effect of changes in dietary diversity on frailty is unclear. This study was conducted to examine the association between the dietary diversity score (DDS) and frailty among older Chinese adults. METHODS: A total of 12,457 adults aged 65 years or older were enrolled from three consecutive and nonoverlapping cohorts from the Chinese Longitudinal Healthy Longevity Survey (the 2002 cohort, the 2005 cohort, and the 2008 cohort). DDS was calculated based on nine predefined food groups, and DDS changes were assessed by comparing scores at baseline and the first follow-up survey. We used 39 self-reported health items to assess frailty. Cox proportional hazard models were performed to examine the association between DDS change patterns and frailty. RESULTS: Participants with low-to-low DDS had the highest frailty incidence (111.1/1000 person-years), while high-to-high DDS had the lowest (41.1/1000 person-years). Compared to the high-to-high group of overall DDS pattern, participants in other DDS change patterns had a higher risk of frailty (HRs ranged from 1.25 to 2.15). Similar associations were observed for plant-based and animal-based DDS. Compared to stable DDS changes, participants with an extreme decline in DDS had an increased risk of frailty, with HRs of 1.38 (1.24, 1.53), 1.31 (1.19, 1.44), and 1.29 (1.16, 1.43) for overall, plant-based, and animal-based DDS, respectively. CONCLUSIONS: Maintaining a lower DDS or having a large reduction in DDS was associated with a higher risk of frailty among Chinese older adults. These findings highlight the importance of improving a diverse diet across old age for preventing frailty in later life.


Assuntos
Dieta , Fragilidade , Humanos , Idoso , Feminino , Masculino , Fragilidade/epidemiologia , China/epidemiologia , Dieta/estatística & dados numéricos , Dieta/métodos , Estudos de Coortes , Idoso Fragilizado/estatística & dados numéricos , Estudos Longitudinais , Idoso de 80 Anos ou mais , Povo Asiático/estatística & dados numéricos , Modelos de Riscos Proporcionais , Avaliação Geriátrica/métodos , Avaliação Geriátrica/estatística & dados numéricos , População do Leste Asiático
19.
J Chem Phys ; 161(10)2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39248383

RESUMO

Polarons are quasiparticles formed as a result of lattice distortions induced by charge carriers. The single-electron Holstein model captures the fundamentals of single polaron physics. We examine the power of the exponential ansatz for the polaron ground-state wavefunction in its coupled cluster, canonical transformation, and (canonically transformed) perturbative variants across the parameter space of the Holstein model. Our benchmark serves to guide future developments of polaron wavefunctions beyond the single-electron Holstein model.

20.
BMC Geriatr ; 24(1): 492, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840066

RESUMO

BACKGROUND: There is limited understanding regarding prospective associations of insomnia symptoms and trajectories with functional disability. We aimed to investigate the associations of insomnia symptoms and trajectories with functional disability. METHOD: A total of 13 197 participants were eligible from the Health and Retirement Study. Insomnia symptoms included non-restorative sleep, difficulty initiating sleep, early morning awakening, and difficulty maintaining sleep. We also identified four distinct trajectories of insomnia symptoms: low, decreasing, increasing, and high insomnia symptoms. Functional status was assessed through activities of daily living (ADL) and instrumental activities of daily living (IADL). RESULTS: Participants experiencing one (HR, 1.21; 95% CI, 1.13-1.29), two (HR, 1.43; 95% CI, 1.29-1.57), or three to four (HR, 1.41; 95% CI, 1.25-1.60) insomnia symptoms had a higher risk of ADL disability than asymptomatic respondents. Similarly, participants with one or more insomnia symptoms had a higher risk of IADL disability. Furthermore, using the trajectory with low insomnia symptoms as the reference, decreasing insomnia symptoms (HR, 1.22; 95% CI, 1.12-1.34), increasing insomnia symptoms (HR, 1.21; 95% CI, 1.05-1.41), and high insomnia symptoms (HR, 1.36; 95% CI, 1.18-1.56) were all associated with an increased risk of ADL disability. CONCLUSION: Both a single measurement and dynamic trajectory of insomnia symptoms are associated with the onset of ADL disability. Increased awareness and management of insomnia symptoms may contribute to the prevention of functional disability occurrence.


Assuntos
Atividades Cotidianas , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Feminino , Masculino , Estudos Prospectivos , Idoso , Pessoa de Meia-Idade , Pessoas com Deficiência , Estudos de Coortes , Avaliação da Deficiência , Fatores de Risco
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