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1.
Neural Regen Res ; 20(3): 715-724, 2025 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38886937

RESUMO

Tropomyosin receptor kinase B (TrkB) signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and memory. The activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre- or postsynaptic TrkB resulting in the strengthening of synapses, reflected by long-term potentiation. Postsynaptically, the association of postsynaptic density protein-95 with TrkB enhances phospholipase Cγ-Ca2+/calmodulin-dependent protein kinase II and phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term potentiation. In this review, we discuss TrkB-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders. A reduction of TrkB signaling has been observed in neurodegenerative disorders, such as Alzheimer's disease and Huntington's disease, and enhancement of postsynaptic density protein-95 association with TrkB signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and depression. Treatment with brain-derived neurotrophic factor is problematic, due to poor pharmacokinetics, low brain penetration, and side effects resulting from activation of the p75 neurotrophin receptor or the truncated TrkB.T1 isoform. Although TrkB agonists and antibodies that activate TrkB are being intensively investigated, they cannot distinguish the multiple human TrkB splicing isoforms or cell type-specific functions. Targeting TrkB-postsynaptic density protein-95 coupling provides an alternative approach to specifically boost TrkB signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

2.
bioRxiv ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38895218

RESUMO

Angelman syndrome (AS) is a rare genetic neurodevelopmental disorder with profoundly debilitating symptoms with no FDA-approved cure or therapeutic. Brain-derived neurotrophic factor (BDNF), and its receptor TrkB, have a well-established role as regulators of synaptic plasticity, dendritic outgrowth, dendritic spine formation and maintenance. Previously, we reported that the association of PSD-95 with TrkB is critical for intact BDNF signaling in the AS mouse model, as illustrated by attenuated PLCγ and PI3K signaling and intact MAPK pathway signaling. These data suggest that drugs tailored to enhance the TrkB-PSD-95 interaction may provide a novel approach for the treatment of AS and a variety of NDDs. To evaluate this critical interaction, we synthesized a class of high-affinity PSD-95 ligands that bind specifically to the PDZ3 domain of PSD-95, denoted as Syn3 peptidomimetic ligands. We evaluated Syn3 and its analog D-Syn3 (engineered using dextrorotary (D)-amino acids) in vivo using the Ube3a exon 2 deletion mouse model of AS. Following systemic administration of Syn3 and D-Syn3, we demonstrated improvement in the seizure domain of AS. Learning and memory using the novel object recognition assay also illustrated improved cognition following Syn3 and D-Syn3, along with restored long-term potentiation. Finally, D-Syn3 treated mice showed a partial rescue in motor learning. Neither Syn3 nor D-Syn3 improved gross exploratory locomotion deficits, nor gait impairments that have been well documented in the AS rodent models. These findings highlight the need for further investigation of this compound class as a potential therapeutic for AS and other genetic NDDs.

3.
Exp Neurol ; 379: 114869, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901755

RESUMO

The protein homeostasis, or proteostasis, is maintained through the coupling of two pivotal systems: the ubiquitin-proteasome and autophagy. Cumulative evidence has suggested E3 ubiquitin ligases specifically play a central role in this coupling, ensuring the regulation of synaptic and cognitive functions. Defects in these ligases have been identified as hallmarks in a range of neurodevelopmental and neurodegenerative disorders. Recent literature has spotlighted the E3 ubiquitin ligase, UBE3A, as a key player in this domain. Dysregulation or loss of UBE3A function has been linked to disrupted proteostasis, leading to synaptic and cognitive anomalies. Notably, such defects are prominently observed in conditions like Angelman syndrome, a neurodevelopmental disorder characterized by severe cognitive impairments. The emerging understanding of UBE3A's role in bridging the ubiquitin-proteasome and autophagy systems offers a promising therapeutic avenue. Targeting the defective pathways caused by UBE3A loss could pave the way for innovative treatments, potentially ameliorating the cognitive deficits observed in neurological disorders like Angelman syndrome. As the scientific community delves deeper into the molecular intricacies of E3 ubiquitin ligases, there is burgeoning hope for devising effective interventions for associated neurological conditions.

4.
J Biol Chem ; : 107494, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38925326

RESUMO

The commitment of stem cells to differentiate into osteoblasts is a highly regulated and complex process that involves the coordination of extrinsic signals and intrinsic transcriptional machinery. While rodent osteoblastic differentiation has been extensively studied, research on human osteogenesis has been limited by cell sources and existing models. Here, we systematically dissect hPSC-derived osteoblasts to identify functional membrane proteins and their downstream transcriptional networks involved in human osteogenesis. Our results reveal an enrichment of type II transmembrane serine protease CORIN in humans but not rodent osteoblasts. Functional analyses demonstrated that CORIN depletion significantly impairs osteogenesis. Genome-wide ChIP enrichment and mechanistic studies show that p38 MAPK-mediated CEBPD upregulation is required for CORIN-modulated osteogenesis. Contrastingly, the type I transmembrane heparan sulfate proteoglycan SDC1 enriched in MSCs exerts a negative regulatory effect on osteogenesis through a similar mechanism. ChIP-seq, bulk and single-cell transcriptomes, and functional validations indicated that CEBPD plays a critical role in controlling osteogenesis. In summary, our findings uncover previously unrecognized CORIN-mediated CEBPD transcriptomic networks in driving human osteoblast lineage commitment.

5.
Sci Rep ; 14(1): 14673, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918427

RESUMO

Visual assessment, while the primary method for pigmentation and erythema evaluation in clinical practice, is subjective, time-consuming, and may lead to variability in observations among clinicians. Objective and quantitative techniques are required for a precise evaluation of the disease's severity and the treatment's efficacy. This research examines the precision and utility of a newly developed skin imaging system in assessing pigmentation and erythema. Sixty participants were recruited, and their facial images were analyzed with the new OBSERV 520 x skin imaging system, compared to DERMACATCH for regional analysis and VISIA for full-face examination. The degree of skin pigmentation was clinically graded using the MASI scores evaluated by dermatologists. The data revealed positive correlations between the novel skin imaging system and the two conventional instruments in quantifying pigmentation and erythema, whether in regional or full-face analysis. Furthermore, the new skin imaging system positively correlated with the clinical MASI scores (r = 0.4314, P < 0.01). In contrast, our study found no significant correlation between the traditional system and clinical assessment, indicating a more substantial capacity for hyperpigmentation assessment in the new system. Our study validates the innovative skin imaging system's accuracy in evaluating pigmentation and erythema, demonstrating its feasibility for quantitative evaluation in both clinical and research purposes.


Assuntos
Eritema , Face , Pigmentação da Pele , Humanos , Feminino , Masculino , Adulto , Eritema/diagnóstico por imagem , Face/diagnóstico por imagem , Pessoa de Meia-Idade , Pele/diagnóstico por imagem , Pele/patologia , Adulto Jovem , Inflamação/diagnóstico por imagem , Idoso , Transtornos da Pigmentação/diagnóstico por imagem , Transtornos da Pigmentação/diagnóstico , Hiperpigmentação/diagnóstico por imagem
6.
Cells ; 13(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38920701

RESUMO

While the transcription factor GATA-3 is well-established for its crucial role in T cell development, its specific influence on invariant natural killer T (iNKT) cells remains relatively unexplored. Using flow cytometry and single-cell transcriptomic analysis, we demonstrated that GATA-3 deficiency in mice leads to the absence of iNKT2 and iNKT17 cell subsets, as well as an altered distribution of iNKT1 cells. Thymic iNKT cells lacking GATA-3 exhibited diminished expression of PLZF and T-bet, key transcription factors involved in iNKT cell differentiation, and reduced production of Th2, Th17, and cytotoxic effector molecules. Single-cell transcriptomics revealed a comprehensive absence of iNKT17 cells, a substantial reduction in iNKT2 cells, and an increase in iNKT1 cells in GATA-3-deficient thymi. Differential expression analysis highlighted the regulatory role of GATA-3 in T cell activation signaling and altered expression of genes critical for iNKT cell differentiation, such as Icos, Cd127, Eomes, and Zbtb16. Notably, restoration of Icos, but not Cd127, expression could rescue iNKT cell development in GATA-3-deficient mice. In conclusion, our study demonstrates the pivotal role of GATA-3 in orchestrating iNKT cell effector lineage differentiation through the regulation of T cell activation pathways and Icos expression, providing insights into the molecular mechanisms governing iNKT cell development and function.


Assuntos
Diferenciação Celular , Linhagem da Célula , Fator de Transcrição GATA3 , Células T Matadoras Naturais , Animais , Fator de Transcrição GATA3/metabolismo , Fator de Transcrição GATA3/genética , Células T Matadoras Naturais/citologia , Células T Matadoras Naturais/metabolismo , Diferenciação Celular/genética , Camundongos , Linhagem da Célula/genética , Camundongos Endogâmicos C57BL , RNA-Seq , Análise de Célula Única , Camundongos Knockout , Análise da Expressão Gênica de Célula Única
7.
Cell Rep ; 43(5): 114226, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38733586

RESUMO

Cognitive dysfunction is a feature in multiple sclerosis (MS), a chronic inflammatory demyelinating disorder. A notable aspect of MS brains is hippocampal demyelination, which is closely associated with cognitive decline. However, the mechanisms underlying this phenomenon remain unclear. Chitinase-3-like (CHI3L1), secreted by activated astrocytes, has been identified as a biomarker for MS progression. Our study investigates CHI3L1's function within the demyelinating hippocampus and demonstrates a correlation between CHI3L1 expression and cognitive impairment in patients with MS. Activated astrocytes release CHI3L1 in reaction to induced demyelination, which adversely affects the proliferation and differentiation of neural stem cells and impairs dendritic growth, complexity, and spine formation in neurons. Our findings indicate that the astrocytic deletion of CHI3L1 can mitigate neurogenic deficits and cognitive dysfunction. We showed that CHI3L1 interacts with CRTH2/receptor for advanced glycation end (RAGE) by attenuating ß-catenin signaling. The reactivation of ß-catenin signaling can revitalize neurogenesis, which holds promise for therapy of inflammatory demyelination.


Assuntos
Astrócitos , Proteína 1 Semelhante à Quitinase-3 , Cognição , Hipocampo , Neurogênese , Transdução de Sinais , Proteína 1 Semelhante à Quitinase-3/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Animais , Astrócitos/metabolismo , Humanos , Camundongos , Cognição/fisiologia , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Masculino , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Feminino , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , beta Catenina/metabolismo , Proliferação de Células , Diferenciação Celular
8.
Micromachines (Basel) ; 15(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38675328

RESUMO

This study demonstrates a particular composited barrier structure of high-electron-mobility transistors (HEMTs) with an enhancement mode composed of p-GaN/GaN/AlN/AlGaN/GaN. The purpose of the composite barrier structure device is to increase the maximum drain current, reduce gate leakage, and achieve lower on-resistance (Ron) performance. A comparison was made between the conventional device without the composited barrier and the device with the composited barrier structure. The maximum drain current is significantly increased by 37%, and Ron is significantly reduced by 23%, highlighting the synergistic impact of the composite barrier structure on device performance improvement. This reason can be attributed to the undoped GaN (u-GaN) barrier layer beneath p-GaN, which was introduced to mitigate Mg diffusion in the capping layer, thus addressing its negative effects. Furthermore, the AlN barrier layer exhibits enhanced electrical properties, which can be attributed to the critical role of high-energy-gap properties that increase the 2DEG carrier density and block leakage pathways. These traps impact the device behavior mechanism, and the simulation for a more in-depth analysis of how the composited barrier structure brings improvement is introduced using Synopsys Sentaurus TCAD.

9.
J Clin Sleep Med ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546033

RESUMO

STUDY OBJECTIVES: The gold standard for diagnosing obstructive sleep apnea (OSA) is polysomnography (PSG). However, PSG is a time-consuming method with clinical limitations. This study aimed to create a wireless radar framework to screen the likelihood of two levels of OSA severity (i.e., moderate-to-severe and severe OSA) in accordance with clinical practice standards. METHODS: We conducted a prospective, simultaneous study using the wireless radar system and PSG in a Northern Taiwan sleep center, involving 196 patients. The wireless radar sleep monitor, incorporating hybrid models such as deep neural decision trees, estimated the respiratory disturbance index relative to the total sleep time established by PSG (RDIPSG_TST), by analyzing continuous-wave signals indicative of breathing patterns. Analyses were performed to examine the correlation and agreement between the RDIPSG_TST and apnea-hypopnea index (AHI), results obtained through PSG. Cut-off thresholds for RDIPSG_TST were determined using Youden's index, and multiclass classification was performed, after which the results were compared. RESULTS: A strong correlation (ρ = 0.91) and agreement (average difference of 0.59 events/h) between AHI and RDIPSG_TST were identified. In terms of the agreement between the two devices, the average difference between PSG-based AHI and radar-based RDIPSG_TST was 0.59 events/h, while 187 out of 196 cases (95.41%) fell within the 95% confidence interval of differences. A moderate-to-severe OSA model achieved an accuracy of 90.3% (cut-off threshold for RDIPSG_TST: 19.2 events/h). A severe OSA model achieved an accuracy of 92.4% (cut-off threshold for RDIPSG_TST: 28.86 events/h). The mean accuracy of multiclass classification performance using these cut-off thresholds was 83.7%. CONCLUSIONS: The wireless-radar-based sleep monitoring device, with cut-off thresholds, can provide rapid OSA screening with acceptable accuracy, and also alleviate the burden on PSG capacity. However, to independently apply this framework, the function of determining the radar-based total sleep time requires further optimizations and verification in future work.

10.
Biochem Pharmacol ; 223: 116140, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513740

RESUMO

Cancer cells consume more glucose and usually overexpress glucose transporters which have become potential targets for the development of anticancer drugs. It has been demonstrated that selective SGLT2 inhibitors, such as canagliflozin and dapagliflozin, display anticancer activity. Here we demonstrated that canagliflozin and dapagliflozin synergistically enhanced the growth inhibitory effect of paclitaxel in cancer cells including ovarian cancer and oral squamous cell carcinoma cells. Canagliflozin also inhibited glucose uptake via GLUTs. The combination of paclitaxel and WZB117, a GLUT inhibitor, exhibited a strong synergy, supporting the notion that inhibition of GLUTs by canagliflozin may also account for the synergy between canagliflozin and paclitaxel. Mechanistic studies in ES-2 ovarian cancer cells revealed that canagliflozin potentiated paclitaxel-induced apoptosis and DNA damaging effect. Paclitaxel in the nanomolar range elevated abnormal mitotic cells as well as aneuploid cells, and canagliflozin further enhanced this effect. Furthermore, canagliflozin downregulated cyclin B1 and phospho-BUBR1 upon spindle assembly checkpoint (SAC) activation by paclitaxel, and may consequently impair SAC. Thus, paclitaxel disturbed microtubule dynamics and canagliflozin compromised SAC activity, together they may induce premature mitotic exit, accumulation of aneuploid cells with DNA damage, and ultimately apoptosis.


Assuntos
Compostos Benzidrílicos , Carcinoma de Células Escamosas , Glucosídeos , Neoplasias Bucais , Neoplasias Ovarianas , Feminino , Humanos , Paclitaxel/farmacologia , Canagliflozina/farmacologia , Mitose , Apoptose , Neoplasias Ovarianas/genética , Glucose/farmacologia , Aneuploidia
11.
NPJ Regen Med ; 9(1): 4, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38242900

RESUMO

Neuromyelitis optica (NMO) is a severe autoimmune inflammatory disease of the central nervous system that affects motor function and causes relapsing disability. Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have been used extensively in the treatment of various inflammatory diseases, due to their potent regulatory roles that can mitigate inflammation and repair damaged tissues. However, their use in NMO is currently limited, and the mechanism underlying the beneficial effects of hUC-MSCs on motor function in NMO remains unclear. In this study, we investigate the effects of hUC-MSCs on the recovery of motor function in an NMO systemic model. Our findings demonstrate that milk fat globule epidermal growth 8 (MFGE8), a key functional factor secreted by hUC-MSCs, plays a critical role in ameliorating motor impairments. We also elucidate that the MFGE8/Integrin αvß3/NF-κB signaling pathway is partially responsible for structural and functional recovery, in addition to motor functional enhancements induced by hUC-MSC exposure. Taken together, these findings strongly support the involvement of MFGE8 in mediating hUC-MSCs-induced improvements in motor functional recovery in an NMO mouse model. In addition, this provides new insight on the therapeutic potential of hUC-MSCs and the mechanisms underlying their beneficial effects in NMO.

12.
Org Lett ; 26(2): 553-558, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38181402

RESUMO

α,ß-Unsaturated carbonyls are essential structural motifs for nucleophiles of disease-related proteins. Methods for stereoselective functionalizations at the α-position include the Morita-Baylis-Hillman, Negishi, Sonogashira, Stille, and Rauhut-Currier reactions. Described here is a method for the diastereodivergent α-homoallylation of cyclic enones via a sequence of conjugate addition, aldol condensation, and diastereoselective [3,3]-sigmatropic rearrangement. Mechanistic investigations revealed that the [3,3]-sigmatropic rearrangement proceeds with transfer of chirality. These inspire a photocatalyzed olefin isomerization of the aldol condensation product leading to a highly diastereoselective [3,3]-sigmatropic rearrangement to furnish the α-homoallylation of cyclic enones. Importantly, this photocatalyzed olefin isomerization/diastereoselective [3,3]-sigmatropic rearrangement reaction sequence permits a full stereocontrol of the exo-ß-position featuring an allyl group as a synthetic functional handle.

13.
RSC Adv ; 14(1): 700-706, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38173585

RESUMO

Selectively producing a variety of valuable compounds using controlled chemical reactions starting from a common material is an appealing yet complex concept. Herein, a photocatalytic approach for the selective synthesis of (E)-ß-aminovinyl sulfones and (E)-ß-amidovinyl sulfones from allenamides and sodium sulfinates was established. This reaction exhibits the traits of an eco-friendly solvent and adjustable amide cleavage, and can accommodate a diverse range of substrates with exceptional functional group tolerance. Based on control experiments and deuterium labeling experiments, a plausible radical reaction pathway is proposed.

14.
Prostate Cancer Prostatic Dis ; 27(1): 116-121, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37660219

RESUMO

BACKGROUND: The Senhance® Robotic System is a new laparoscopy-based platform that has been increasingly used in radical prostatectomy (RP) procedures. The purpose of this study is to compare the outcome of Senhance RP (SRP) with da Vinci RP (DRP) cases. METHODS: From August 2019 to April 2022, we prospectively recruited 63 cases of SRP. We compared the perioperative data, postoperative complication rates, short-term surgical outcomes (3-month postoperative undetectable prostate-specific antigen (PSA) and incontinence rates), learning curves, and cost analysis with data from 63 matched da Vinci Xi RP cases. RESULTS: There was no difference in BL (180 versus 180 ml, p = 0.86) and postoperative surgical complication rate (Clavient -Dindo grade I-IV, 25.3 versus 22.2%, p = 0.21) between the SRP cases and the DRP. Regarding the oncologic and continence function, there was no difference between positive margin rate (36.5% versus 41.3%, p = 0.58), rate of undetectable PSA level at postoperative 3 months (68.3 versus 66.7%, p = 0.85), and incontinence rate (14.3 versus 15.9%, p = 1.0) at postoperative 3 months between the two cohorts. The learning curve showed a quick downward slope for laparoscopic experienced surgeons. The median pocket cost for SRP patients in our hospital was $4170, which was lower than $7675 for the DRP patients. CONCLUSIONS: Safety and short-term outcomes are comparable between SRP and DRP. For experienced LRP surgeons, using the Senhance system to perform RP is straightforward. With a more affordable price as its biggest advantage, the Senhance system may serve as a safe and effective alternative for robotic RP.


Assuntos
Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Incontinência Urinária , Masculino , Humanos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Curva de Aprendizado , Antígeno Prostático Específico , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/etiologia , Prostatectomia/métodos , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia , Custos e Análise de Custo , Resultado do Tratamento
15.
Int J Biol Sci ; 19(16): 5174-5186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928274

RESUMO

Chondrosarcoma is the second most common type of bone cancer. At present, the most effective clinical course of action is surgical resection. Cisplatin is the chemotherapeutic medication most widely used for the treatment of chondrosarcoma; however, its effectiveness is severely hampered by drug resistance. In the current study, we compared cisplatin-resistant chondrosarcoma SW1353 cells with their parental cells via RNA sequencing. Our analysis revealed that glutamine metabolism is highly activated in resistant cells but glucose metabolism is not. Amphiregulin (AR), a ligand of the epidermal growth factor receptor, enhances glutamine metabolism and supports cisplatin resistance in human chondrosarcoma by promoting NADPH production and inhibiting reactive oxygen species (ROS) accumulation. The MEK, ERK, and NrF2 signaling pathways were shown to regulate AR-mediated alanine-serine-cysteine transporter 2 (ASCT2; also called SLC1A5) and glutaminase (GLS) expression as well as glutamine metabolism in cisplatin-resistant chondrosarcoma. The knockdown of AR expression in cisplatin-resistant chondrosarcoma cells was shown to reduce the expression of SLC1A5 and GLS in vivo. These results indicate that AR and glutamine metabolism are worth pursuing as therapeutic targets in dealing with cisplatin-resistant human chondrosarcoma.


Assuntos
Neoplasias Ósseas , Condrossarcoma , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Anfirregulina/genética , Glutamina , Resistencia a Medicamentos Antineoplásicos/genética , Condrossarcoma/tratamento farmacológico , Condrossarcoma/genética , Linhagem Celular Tumoral , Antígenos de Histocompatibilidade Menor , Sistema ASC de Transporte de Aminoácidos
16.
Sci Adv ; 9(47): eadk1910, 2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-37992165

RESUMO

Endozoicomonas are often predominant bacteria and prominently important in coral health. Their role in dimethylsulfoniopropionate (DMSP) degradation has been a subject of discussion for over a decade. A previous study found that Endozoicomonas degraded DMSP through the dddD pathway. This process releases dimethyl sulfide, which is vital for corals coping with thermal stress. However, little is known about the related gene regulation and metabolic abilities of DMSP metabolism in Endozoicomonadaceae. In this study, we isolated a novel Endozoicomonas DMSP degrader and observed a distinct DMSP metabolic trend in two phylogenetically close dddD-harboring Endozoicomonas species, confirmed genetically by comparative transcriptomic profiling and visualization of the change of DMSP stable isotopes in bacterial cells using nanoscale secondary ion spectrometry. Furthermore, we found that DMSP cleavage enzymes are ubiquitous in coral Endozoicomonas with a preference for having DddD lyase. We speculate that harboring DMSP degrading genes enables Endozoicomonas to successfully colonize various coral species across the globe.


Assuntos
Antozoários , Compostos de Sulfônio , Animais , Antozoários/metabolismo , Bactérias/metabolismo , Compostos de Sulfônio/metabolismo
17.
J Org Chem ; 88(24): 17227-17236, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38019169

RESUMO

This study presents a convenient approach to the synthesis of indole- and benzofuran-based benzylic sulfones using unactivated alkynes containing aryl iodides and sodium sulfinates under visible light irradiation. The procedure involves a sequential series of dehalogenation, carbo-cyclization, and radical sulfonylation. Plausible insights into the reaction mechanism are derived from control experiments, leading to the proposal of a radical cascade reaction pathway.

18.
Nano Lett ; 23(21): 9811-9816, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37708490

RESUMO

Extreme ultraviolet (EUV) radiation with wavelengths of 10-121 nm has drawn considerable attention recently for its use in photolithography to fabricate nanoelectronic chips. This study demonstrates, for the first time, fluorescent nanodiamonds (FNDs) with nitrogen-vacancy (NV) centers as scintillators to image and characterize EUV radiations. The FNDs employed are ∼100 nm in size; they form a uniform and stable thin film on an indium-tin-oxide-coated slide by electrospray deposition. The film is nonhygroscopic and photostable and can emit bright red fluorescence from NV0 centers when excited by EUV light. An FND-based imaging device has been developed and applied for beam diagnostics of 50 nm and 13.5 nm synchrotron radiations, achieving a spatial resolution of 30 µm using a film of ∼1 µm thickness. The noise equivalent power density is 29 µW/(cm2 Hz1/2) for the 13.5 nm radiation. The method is generally applicable to imaging EUV radiation from different sources.

19.
Sci Adv ; 9(39): eadg8148, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37756391

RESUMO

Chitinase-3-like protein 1 (CHI3L1) is primarily secreted by activated astrocytes in the brain and is known as a reliable biomarker for inflammatory central nervous system (CNS) conditions such as neurodegeneration and autoimmune disorders like neuromyelitis optica (NMO). NMO is an astrocyte disease caused by autoantibodies targeting the astroglial protein aquaporin 4 (AQP4) and leads to vision loss, motor deficits, and cognitive decline. In this study examining CHI3L1's biological function in neuroinflammation, we found that CHI3L1 expression correlates with cognitive impairment in our NMO patient cohort. Activated astrocytes secrete CHI3L1 in response to AQP4 autoantibodies, and this inhibits the proliferation and neuronal differentiation of neural stem cells. Mouse models showed decreased hippocampal neurogenesis and impaired learning behaviors, which could be rescued by depleting CHI3L1 in astrocytes. The molecular mechanism involves CHI3L1 engaging the CRTH2 receptor and dampening ß-catenin signaling for neurogenesis. Blocking this CHI3L1/CRTH2/ß-catenin cascade restores neurogenesis and improves cognitive deficits, suggesting the potential for therapeutic development in neuroinflammatory disorders.

20.
Prog Neurobiol ; 230: 102513, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37536482

RESUMO

Angelman Syndrome (AS) is a severe cognitive disorder caused by loss of neuronal expression of the E3 ubiquitin ligase UBE3A. In an AS mouse model, we previously reported a deficit in brain-derived neurotrophic factor (BDNF) signaling, and set out to develop a therapeutic that would restore normal signaling. We demonstrate that CN2097, a peptidomimetic compound that binds postsynaptic density protein-95 (PSD-95), a TrkB associated scaffolding protein, mitigates deficits in PLC-CaMKII and PI3K/mTOR pathways to restore synaptic plasticity and learning. Administration of CN2097 facilitated long-term potentiation (LTP) and corrected paired-pulse ratio. As the BDNF-mTORC1 pathway is critical for inhibition of autophagy, we investigated whether autophagy was disrupted in AS mice. We found aberrantly high autophagic activity attributable to a concomitant decrease in mTORC1 signaling, resulting in decreased levels of synaptic proteins, including Synapsin-1 and Shank3. CN2097 increased mTORC1 activity to normalize autophagy and restore hippocampal synaptic protein levels. Importantly, treatment mitigated cognitive and motor dysfunction. These findings support the use of neurotrophic therapeutics as a valuable approach for treating AS pathology.


Assuntos
Síndrome de Angelman , Peptidomiméticos , Animais , Camundongos , Síndrome de Angelman/tratamento farmacológico , Síndrome de Angelman/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Potenciação de Longa Duração , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Peptidomiméticos/metabolismo , Fatores de Transcrição/metabolismo
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