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1.
J Environ Sci (China) ; 147: 677-687, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39003082

RESUMO

Due to their resistance to degradation, wide distribution, easy diffusion and potential uptake by organisms, microplastics (MPs) pollution has become a major environmental concern. In this study, PEG-modified Fe3O4 magnetic nanoparticles demonstrated superior adsorption efficiency against polyethylene (PE) microspheres compared to other adsorbents (bare Fe3O4, PEI/Fe3O4 and CA/Fe3O4). The maximum adsorption capacity of PE was found to be 2203 mg/g by adsorption isotherm analysis. PEG/Fe3O4 maintained a high adsorption capacity even at low temperature (5°C, 2163 mg/g), while neutral pH was favorable for MP adsorption. The presence of anions (Cl-, SO42-, HCO3-, NO3-) and of humic acids inhibited the adsorption of MPs. It is proposed that the adsorption process was mainly driven by intermolecular hydrogen bonding. Overall, the study demonstrated that PEG/Fe3O4 can potentially be used as an efficient control against MPs, thus improving the quality of the aquatic environment and of our water resources.


Assuntos
Microplásticos , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Cinética , Adsorção , Polietileno/química , Nanopartículas de Magnetita/química , Polietilenoglicóis/química , Modelos Químicos
2.
Chem Commun (Camb) ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39350731

RESUMO

We present a fabrication process for hierarchical (Ni,Co)0.85Se sheets, achieving efficient oxygen evolution reaction (OER) activity with a 10 mA cm-2 current density at an overpotential of 290 mV. Porous architecture and doping improve kinetics, supported by DFT calculations. This approach offers insights into designing stable, high-performance OER catalysts.

3.
Plant Physiol Biochem ; 216: 109168, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39366198

RESUMO

Long-distance signals play a vital role in plant stress response. γ-aminobutyric acid (GABA) has been proposed to be a signal and protects crops against diverse stresses. However, whether GABA acts as a long-distance signal to plant response to stresses remains unknown. Here, we found that the GABA content in cucurbita rootstocks, especially figleaf gourd, was significantly higher than that in cucumber. Figleaf gourd rootstock obviously enhanced cold tolerance and GABA accumulation in roots, xylem sap and leaves of grafting cucumber seedlings. Conversely, GABA synthesis inhibitor 3-mercaptopropionic acid (3-MPA) irrigation was more effective than its foliar application in inhibiting grafting-induced cold tolerance. Moreover, fluorescence microscopy confirmed that GABA can be transported from root to shoot through the xylem when the roots of grafted seedlings were fed with fluorescein isothiocyatate-labeled GABA under normal and cold stress conditions. Importantly, 3-MPA irrigation attenuated grafting-induced cold tolerance, as revealed by a decline in the GABA accumulation, the transcripts of ICE1, CBF1 and COR47, the activities of the antioxidant enzymes, and an increase in stomatal aperture. Collectively, our findings strongly support that GABA functions as a novel long-distance signal in figleaf gourd rootstock-induced cold tolerance of grafted cucumber seedlings by modulating CBF-signalling pathways, antioxidant system and stomatal aperture, providing new evidence for long-distance signaling-mediated cold response of plants.

5.
ChemSusChem ; : e202401871, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400469

RESUMO

Developing stable and active electrocatalysts is crucial for enhancing the oxygen evolution reaction (OER) efficiency, which sluggish kinetics hinders sustainable hydrogen production. High entropy selenides (HESes) features with random distribution of multiple metals cations and unique electronic and size effect of Se anion, allowing for precious regulation of their catalytic properties towards high OER activity. In this work, we report a series of high-entropy selenides catalysts with tunable lattice strain for electrocatalytic oxygen evolution. Electrochemical measurements show that the quinary (NiCoMnMoFe)Sex requires only 291 mV to reach 10 mA cm-2 and exhibits a superior stability with negligible current decay during 100 h's continuous operation. By combining experimental measurements and theoretical calculation, the study reveals that the lattice distortion, reflected by the local microstrain near the active site, plays a vital role in boosting the OER activity of HESes.

6.
Clin Psychopharmacol Neurosci ; 22(4): 594-609, 2024 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-39420607

RESUMO

Objective: Whether peripheral blood 5-hydroxytrptamine (5-HT) levels serve as biomarker for depression diagnosis/response evaluation has not been well determined. This work was explored to address this inconclusive issue. Methods: Animals were randomized into normal control group (NC, n = 10) and chronic unpredictable mild stress model group (CUMS-model, n = 20), respectively. Animals in CUMS-model group were subjected to chronic stress, then they were randomly subdivided into CUMS subgroup and CUMS + fluoxetine subgroup (CUMS + FLX). After FLX treatment, blood and tissues were collected. 5-HT and relevant protein expression were measured. Results: In mice model, there was a significant increase in serum and a significant reduction in plasma 5-HT levels in CUMS-model group versus NC group, while platelet 5-HT levels change little. After FLX treatment, serum and platelet 5-HT levels were significantly decreased in CUMS + FLX subgroup, while plasma 5-HT levels had not much change versus CUMS subgroup. Chronic stress enhanced colon and platelet serotonin transporter (SERT) expression and FLX treatment mitigated SERT expression. In rats' model, there was a significant increase in serum 5-HT levels while plasma and platelet 5-HT levels showed little change in CUMS group versus NC group. After FLX treatment, serum, plasma and platelet 5-HT levels were significantly decreased in CUMS + FLX subgroup versus CUMS subgroup. The profile of relevant proteins expression changed by FLX were like those in mice. Conclusion: Serum 5-HT levels might serve as a potential biomarker for depression diagnosis, meanwhile serum and platelet 5-HT levels might respond to antidepressant treatment.

7.
iScience ; 27(9): 110680, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39252980

RESUMO

Cancer prevention is a serious global challenge. We aimed to investigate the relationship between lipid-lowering drugs and cancers. We included participants based on the UK Biobank. Lipid-lowering drug use was defined as new users before enrollment and the primary outcome was cancer incidence. The Cox proportional hazards regression model was used to evaluate the association between drug use and outcome. We also performed a meta-analysis. We found that lipid-lowering drugs were associated with decreased risk of 21 types of cancers, including melanoma, skin cancer, and reproductive, hematological, urinary, digestive, nervous, and endocrine system cancers (all p < 0.0010). Our meta-analysis documented that lipid-lowering drugs reduced the risk of prostate, liver, and gastric cancers, especially (all p < 0.050). Overall, lipid-lowering drugs had protective associations with cancer incidence, suggesting the possible cancer prevention effects even in the general population.

8.
Cancer Gene Ther ; 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39300219

RESUMO

Circular RNA (circRNA) has been demonstrated to play a pivotal role in tumor development. This study aimed to investigate the regulatory mechanism of circMBOAT2 in non-small cell lung cancer (NSCLC) and its association with tumor growth induced by chronic stress. We constructed stably transfected A549 and H1299 cell lines with circMBOAT2 overexpression and knockdown. Colony formation, scratch healing, Transwell and CCK-8 assays were conducted to evaluate the effects of circMBOAT2 in the presence or absence of norepinephrine (NE) treatment on the proliferation, migration, and invasion of NSCLC cells, respectively. Additionally, A chronic unpredictable mild stress (CUMS)-induced depression with heterotopic transplantation LLC and injection of antisense oligonucleotides (ASOs) targeting circMBOAT2 mouse model was established to evaluate the effect of chronic stress on tumorigenesis via circMBOAT2. Moreover, we investigated the regulatory effect of CCCTC binding factor (CTCF) on circMBOAT2 expression through in vivo and in vitro silencing of CTCF. Our results revealed a significant upregulation of circMBOAT2 in NSCLC cell lines and tumor tissues. circMBOAT2 knockdown inhibited the proliferation, migration, and invasion of NSCLC cells, while NE treatment reversed the cell suppression effect caused by circMBOAT2 knockdown. Notably, CUMS promoted tumor growth, while silencing circMBOAT2 inhibited tumor growth in vivo. Furthermore, we identified CTCF as the upstream regulator of circMBOAT2, which exhibited upregulation in NSCLC cells and tissues. Knockdown of CTCF reversed the promotional effect of CUMS on circMBOAT2 expression and tumor growth. Our findings provide evidence that CTCF mediates chronic stress in promoting of NSCLC progression through circMBOAT2. circMBOAT2 may serve as a potential biomarker and therapeutic target for NSCLC as well as the treatment of comorbid depression in NSCLC patients.

9.
Drug Des Devel Ther ; 18: 4135-4151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39308693

RESUMO

Objective: This study aimed to identify the effectiveness and safety of PD-1 blockades among elderly patients with metastatic esophageal squamous cell carcinoma (ESCC) clinically. Methods: A total of 78 elderly patients with previously treated metastatic ESCC aged ≥65 years who received PD-1 blockades monotherapy were included retrospectively. Demographic characteristics, therapeutic effectiveness and adverse reactions of the elderly patients who underwent PD-1 blockade therapy were recorded. Regular follow-up was conducted for all patients. The analysis aimed to identify potential risk factors for OS by examining the correlation between prognosis and subgroups based on baseline characteristics. Results: The median age of the 78 elderly patients was 73 years, ranging from 65 to 87 years. Among the 78 patients, 18 cases showed partial response, 26 cases had stable disease, 29 cases experienced progressive disease and 5 cases were not assessable for response, yielding an ORR of 23.1%, a DCR of 56.4%. The prognostic outcomes indicated that among the 78 patients with metastatic ESCC who received PD-1 blockades, the median PFS was 3.1 months [95% confidence interval (CI): 1.64-4.56], and the median OS was 10.9 months (95% CI: 6.02-15.78), 24-month OS rate was 22.7% (95% CI: 12.8-34.2%). In terms of the safety profile, among the 78 patients with metastatic ESCC during PD-1 blockades single-agent treatment, a total of 61 patients (78.2%) experienced any grade adverse reactions and the incidence of grade ≥3 adverse reactions were 20.5%. Briefly, the common adverse reactions manifested as fatigue (32.1%), gastrointestinal reaction (24.4%), diarrhea (19.2%), anemia (17.9%) and rash (16.7%). Overall tolerability of PD-1 blockade monotherapy in elderly patients with metastatic ESCC was acceptable and manageable. Conclusion: PD-1 blockades single agent demonstrated encouraging effectiveness and acceptable safety profile for elderly patients with previously treated metastatic ESCC in clinical practice. Prospective study should be performed to elucidate the conclusion in this study subsequently.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Estudos de Viabilidade , Receptor de Morte Celular Programada 1 , Humanos , Idoso , Masculino , Idoso de 80 Anos ou mais , Feminino , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , Estudos Retrospectivos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/uso terapêutico , Metástase Neoplásica
10.
Chin J Cancer Res ; 36(4): 351-367, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39246704

RESUMO

Objective: CD8+ T cells are the key effector cells in the anti-tumor immune response. The mechanism underlying the infiltration of CD8+ T cells in esophageal squamous cell carcinoma (ESCC) has not been clearly elucidated. Methods: Fresh ESCC tissues were collected and grouped according to the infiltration density of CD8+ T cells. After the transcriptome sequencing on these samples and the combined analyses with The Cancer Genome Atlas (TCGA) ESCC data, a secreted protein DEFB1 was selected to explore its potential role in the infiltration of CD8+ T cells. Bioinformatics analyses, histological verification and in vitro experiments were then performed. Results: DEFB1 was highly expressed in ESCC, and the high expression of DEFB1 was an independent risk factor for overall survival. Since the up-regulation or down-regulation of DEFB1 did not affect the proliferation, migration and apoptosis of ESCC cells, we speculated that the oncogenic effect of DEFB1 was achieved by regulating microenvironmental characteristics. Bioinformatics analyses suggested that DEFB1 might play a major role in the inflammatory response and anti-tumor immune response, and correlate to the infiltration of immature dendritic cell (imDC) in ESCC. Histological analyses further confirmed that there were less CD8+ T cells infiltrated, less CD83+ mature DC (mDC) infiltrated and more CD1a+ imDC infiltrated in those ESCC samples with high expression of DEFB1. After the treatment with recombinant DEFB1 protein, the maturation of DC was hindered significantly, followed by the impairment of the killing effects of T cells in both 2D and 3D culture in vitro. Conclusions: Tumor-derived DEFB1 can inhibit the maturation of DC and weaken the function of CD8+ T cells, accounting for the immune tolerance in ESCC. The role of DEFB1 in ESCC deserves further exploration.

11.
J Struct Biol ; 216(3): 108117, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39153560

RESUMO

The complement system is a complex network of proteins that plays a crucial role in the innate immune response. One important component of this system is the C5a-C5aR1 complex, which is critical in the recruitment and activation of immune cells. In-depth investigation of the activation mechanism as well as biased signaling of the C5a-C5aR1 system will facilitate the elucidation of C5a-mediated pathophysiology. In this study, we determined the structure of C5a-C5aR1-Gi complex at a high resolution of 3 Å using cryo-electron microscopy (Cryo-EM). Our results revealed the binding site of C5a, which consists of a polar recognition region on the extracellular side and an amphipathic pocket within the transmembrane domain. Furthermore, we found that C5a binding induces conformational changes of C5aR1, which subsequently leads to the activation of G protein signaling pathways. Notably, a key residue (M265) located on transmembrane helix 6 (TM6) was identified to play a crucial role in regulating the recruitment of ß-arrestin driven by C5a. This study provides more information about the structure and function of the human C5a-C5aR1 complex, which is essential for the proper functioning of the complement system. The findings of this study can also provide a foundation for the design of new pharmaceuticals targeting this receptor with bias or specificity.


Assuntos
Complemento C5a , Microscopia Crioeletrônica , Receptor da Anafilatoxina C5a , Microscopia Crioeletrônica/métodos , Humanos , Receptor da Anafilatoxina C5a/química , Receptor da Anafilatoxina C5a/metabolismo , Sítios de Ligação , Complemento C5a/química , Complemento C5a/metabolismo , Ligação Proteica , Transdução de Sinais , Conformação Proteica , Modelos Moleculares
12.
Nat Commun ; 15(1): 7060, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152107

RESUMO

Industrial CO2 electrolysis via electrochemical CO2 reduction has achieved progress in alkaline solutions, while the same reaction in acidic solution remains challenging because of severe hydrogen evolution side reactions, acid corrosion, and low target product selectivity. Herein, an industrial acidic CO2 electrolysis to pure HCOOH system is realized in a proton-exchange-membrane electrolyzer using an acid-tolerant Bi-based metal-organic framework guided by a Pourbaix diagram. Significantly, the Faradaic efficiency of HCOOH synthesis reaches 95.10% at a large current density of 400 mA/cm2 with a high CO2 single-pass conversion efficiency of 64.91%. Moreover, the proton-exchange-membrane device also achieves an industrial-level current density of 250 mA/cm2 under a relatively low voltage of 3.5 V for up to 100 h with a Faradaic efficiency of 93.5% for HCOOH production, which corresponds to an energy consumption of 200.65 kWh/kmol, production rate of 12.1 mmol/m2/s, and an energy conversion efficiency of 38.2%. These results will greatly aid the contemporary research moving toward commercial implementation and success of CO2 electrolysis technology.

13.
Adv Mater ; 36(36): e2401641, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39032092

RESUMO

The hydrogenation of small molecules (like O2 and CO2) often exhibits strong activity dependence on pHs because of discrepant proton donor environments. However, some catalysts can show seldom dependence on two-electron oxygen electroreduction, a sustainable route of O2 hydrogenation to hydrogen peroxide (H2O2). In this work, a pH-resistant oxygen electroreduction system arising from the pseudo-Jahn-Teller effect is demonstrated. Thorough operando Raman spectra, local environment analyses and density function theory simulations, the lattice distortion of TiOxFy that introduces the pseudo-Jahn-Teller effect contributing to regulating local pHs at electrode-electrolyte interfaces and the absorption/desorption of key *OOH intermediate is revealed. Consequently, as comparison to 78.6% activity attenuation for common catalyst, the TiOxFy displays minor activity decay (3.2%) in the pH range of 1-13 with remarkable Faradaic efficiencies (93.4-96.4%) and H2O2 yield rates (595-614 mg cm-2 h-1) in the current densities of 100-1000 mA cm-2. Further techno-economics analyses display the H2O2 production cost dependent on pHs, giving the lowest H2O2 price of $0.37 kg-1. The present finding is expected to provide an additional dimension to pseudo-Jahn-Teller effect that leverages systems beyond traditional conception.

15.
CNS Neurosci Ther ; 30(7): e14862, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39009505

RESUMO

BACKGROUND: The emergence of cyclin-dependent kinases 4/6 inhibitors (CDK4/6i) represented a major breakthrough in the treatment of breast cancer over the past decade. In both clinical trials and real-world settings, it was observed that patients using CDK4/6i might experience psychiatric adverse events (PAEs). Herein, we conducted a pharmacovigilance study to comprehensively assess the correlation between CDK4/6i and PAEs. METHOD: We obtained individual case safety reports submitted to the FDA Adverse Events Reporting System (FAERS) during the period from January 2015 to December 2023. In disproportionality analysis, the reporting odds ratio (ROR) and information component (IC) values were calculated for each adverse event-drug combination. Univariate logistic regression analysis was utilized to explore factors associated with PAEs following CDK4/6i treatment. RESULTS: A total of 95,591 reports related to CDK4/6i were identified, with 6.72% reporting PAEs, and this proportion exhibited an annual upward trend. Based on the ROR and IC values, 17 categories of PAEs were defined as CDK4/6i-related PAEs. Among these PAEs, insomnia, stress, eating disorder, depressed mood, and sleep disorder were very common, each accounting for over 10% of CDK4/6i reports. Ribociclib showed the highest risk signal of CDK4/6i-related PAEs (ROR = 1.89[1.75-2.04], IC025 = 0.79), followed by palbociclib (ROR = 1.47[1.41-1.53], IC025 = 0.49), while abemaciclib did not exhibit a significant signal (ROR = 0.52[0.44-0.62], IC025 = -1.13). Female sex, younger age and weight exceeding 80 kg were significant risk factors for the incidence of CDK4/6i-related PAEs. CONCLUSIONS: Using data from a real-world, large-scale spontaneous reporting system for adverse drug reactions, our study delineated the spectrum of PAEs to CDK4/6i. This potentially offered valuable insights for healthcare professionals to manage the risk of PAEs in patients receiving CDK4/6i treatment, particularly those with psychiatric disorders.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos , Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Transtornos Mentais , Farmacovigilância , Inibidores de Proteínas Quinases , United States Food and Drug Administration , Humanos , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Feminino , Masculino , Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Idoso , Transtornos Mentais/induzido quimicamente , Transtornos Mentais/epidemiologia , Adulto , United States Food and Drug Administration/tendências , Inibidores de Proteínas Quinases/efeitos adversos , Adulto Jovem , Adolescente , Idoso de 80 Anos ou mais
16.
World J Clin Cases ; 12(21): 4642-4651, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39070806

RESUMO

BACKGROUND: Studies have revealed that Children's psychological, behavioral, and emotional problems are easily influenced by the family environment. In recent years, the family structure in China has undergone significant changes, with more families having two or three children. AIM: To explore the relationship between emotional behavior and parental job stress in only preschool and non-only preschool children. METHODS: Children aged 3-6 in kindergartens in four main urban areas of Shijiazhuang were selected by stratified sampling for a questionnaire and divided into only and non-only child groups. Their emotional behaviors and parental pressure were compared. Only and non-only children were paired in a 1:1 ratio by class and age (difference less than or equal to 6 months), and the matched data were compared. The relationship between children's emotional behavior and parents' job stress before and after matching was analyzed. RESULTS: Before matching, the mother's occupation, children's personality characteristics, and children's rearing patterns differed between the groups (P < 0.05). After matching 550 pairs, differences in the children's parenting styles remained. There were significant differences in children's gender and parents' attitudes toward children between the two groups. The Strengths and Difficulties Questionnaire (SDQ) scores of children in the only child group and the Parenting Stress Index-Short Form (PSI-SF) scores of parents were significantly lower than those in the non-only child group (P < 0.05). Pearson's correlation analysis showed that after matching, there was a positive correlation between children's parenting style and parents' attitudes toward their children (r = 0.096, P < 0.01), and the PSI-SF score was positively correlated with children's gender, parents' attitudes toward their children, and SDQ scores (r = 0.077, 0.193, 0.172, 0.222). CONCLUSION: Preschool children's emotional behavior and parental pressure were significantly higher in multi-child families. Parental pressure in differently structured families was associated with many factors, and preschool children's emotional behavior was positively correlated with parental pressure.

17.
Nutrients ; 16(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38892556

RESUMO

Sphingosine-1-phosphate lyase (SPL) resides at the endpoint of the sphingolipid metabolic pathway, catalyzing the irreversible breakdown of sphingosine-1-phosphate. Depletion of SPL precipitates compromised muscle morphology and function; nevertheless, the precise mechanistic underpinnings remain elusive. Here, we elucidate a model of SPL functional deficiency in Caenorhabditis elegans using spl-1 RNA interference. Within these SPL-deficient nematodes, we observed diminished motility and perturbed muscle fiber organization, correlated with the accumulation of sphingoid bases, their phosphorylated forms, and ceramides (collectively referred to as the "sphingolipid rheostat"). The disturbance in mitochondrial morphology was also notable, as SPL functional loss resulted in heightened levels of reactive oxygen species. Remarkably, the administration of the antioxidant N-acetylcysteine (NAC) ameliorates locomotor impairment and rectifies muscle fiber disarray, underscoring its therapeutic promise for ceramide-accumulation-related muscle disorders. Our findings emphasize the pivotal role of SPL in preserving muscle integrity and advocate for exploring antioxidant interventions, such as NAC supplementation, as prospective therapeutic strategies for addressing muscle function decline associated with sphingolipid/ceramide metabolism disruption.


Assuntos
Acetilcisteína , Aldeído Liases , Caenorhabditis elegans , Ceramidas , Esfingolipídeos , Animais , Caenorhabditis elegans/efeitos dos fármacos , Acetilcisteína/farmacologia , Ceramidas/metabolismo , Aldeído Liases/metabolismo , Esfingolipídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Interferência de RNA , Esfingosina/análogos & derivados , Esfingosina/metabolismo
18.
Zool Res ; 45(3): 535-550, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38747058

RESUMO

Proper regulation of synapse formation and elimination is critical for establishing mature neuronal circuits and maintaining brain function. Synaptic abnormalities, such as defects in the density and morphology of postsynaptic dendritic spines, underlie the pathology of various neuropsychiatric disorders. Protocadherin 17 (PCDH17) is associated with major mood disorders, including bipolar disorder and depression. However, the molecular mechanisms by which PCDH17 regulates spine number, morphology, and behavior remain elusive. In this study, we found that PCDH17 functions at postsynaptic sites, restricting the number and size of dendritic spines in excitatory neurons. Selective overexpression of PCDH17 in the ventral hippocampal CA1 results in spine loss and anxiety- and depression-like behaviors in mice. Mechanistically, PCDH17 interacts with actin-relevant proteins and regulates actin filament (F-actin) organization. Specifically, PCDH17 binds to ROCK2, increasing its expression and subsequently enhancing the activity of downstream targets such as LIMK1 and the phosphorylation of cofilin serine-3 (Ser3). Inhibition of ROCK2 activity with belumosudil (KD025) ameliorates the defective F-actin organization and spine structure induced by PCDH17 overexpression, suggesting that ROCK2 mediates the effects of PCDH17 on F-actin content and spine development. Hence, these findings reveal a novel mechanism by which PCDH17 regulates synapse development and behavior, providing pathological insights into the neurobiological basis of mood disorders.


Assuntos
Citoesqueleto de Actina , Caderinas , Espinhas Dendríticas , Protocaderinas , Quinases Associadas a rho , Animais , Camundongos , Citoesqueleto de Actina/metabolismo , Caderinas/metabolismo , Caderinas/genética , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/fisiologia , Regulação da Expressão Gênica , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/genética , Protocaderinas/genética , Protocaderinas/metabolismo
19.
J Biol Chem ; 300(6): 107288, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636662

RESUMO

HCN channels are important for regulating heart rhythm and nerve activity and have been studied as potential drug targets for treating depression, arrhythmia, nerve pain, and epilepsy. Despite possessing unique pharmacological properties, HCN channels share common characteristics in that they are activated by hyperpolarization and modulated by cAMP and other membrane lipids. However, the mechanisms of how these ligands bind and modulate HCN channels are unclear. In this study, we solved structures of full-length human HCN3 using cryo-EM and captured two different states, including a state without any ligand bound and a state with cAMP bound. Our structures reveal the novel binding sites for cholesteryl hemisuccinate in apo state and show how cholesteryl hemisuccinate and cAMP binding cause conformational changes in different states. These findings explain how these small modulators are sensed in mammals at the molecular level. The results of our study could help to design more potent and specific compounds to influence HCN channel activity and offer new therapeutic possibilities for diseases that lack effective treatment.


Assuntos
Microscopia Crioeletrônica , AMP Cíclico , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Humanos , Sítios de Ligação , AMP Cíclico/metabolismo , Células HEK293 , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/química , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Conformação Proteica
20.
J Biol Chem ; 300(6): 107320, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677510

RESUMO

Sphingolipids, essential membrane components and signaling molecules in cells, have ceramides at the core of their metabolic pathways. Initially termed as "longevity assurance genes", the encoding genes of ceramide synthases are closely associated with individual aging and stress responses, although the mechanisms remain unclear. This study aims to explore the alterations and underlying mechanisms of three ceramide synthases, HYL-1, HYL-2, and LAGR-1, in the aging and stress responses of Caenorhabditis elegans. Our results showed the knockdown of HYL-1 extends the lifespan and enhance stress resistance in worms, whereas the loss of HYL-2 function significantly impairs tolerances to heat, oxidation, and ultraviolet stress. Stress intolerance induced by HYL-2 deficiency may result from intracellular mitochondrial dysfunction, accumulation of reactive oxygen species, and abnormal nuclear translocation of DAF-16 under stress conditions. Loss of HYL-2 led to a significant reduction of predominant ceramides (d17:1/C20∼C23) as well as corresponding complex sphingolipids. Furthermore, the N-acyl chain length composition of sphingolipids underwent dramatic modifications, characterized by a decrease in C22 sphingolipids and an increase in C24 sphingolipids. Extra d18:1-ceramides resulted in diminished stress resilience in wild-type worms, while supplementation of d18:1/C16 ceramide to HYL-2-deficient worms marginally improved stress tolerance to heat and oxidation. These findings indicate the importance of appropriate ceramide content and composition in maintaining subcellular homeostasis and nuclear-cytoplasmic signal transduction during healthy aging and stress responses.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Esfingolipídeos , Animais , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Ceramidas/metabolismo , Fatores de Transcrição Forkhead , Longevidade , Estresse Oxidativo , Oxirredutases/metabolismo , Oxirredutases/genética , Espécies Reativas de Oxigênio/metabolismo , Esfingolipídeos/metabolismo , Estresse Fisiológico
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