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1.
Proc Natl Acad Sci U S A ; 120(34): e2306950120, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37590412

RESUMEN

Hybrid voltage indicators (HVIs) are chemogenetic sensors that combines the superior photophysical properties of organic dyes and the genetic targetability of protein sensors to report transient membrane voltage changes. They exhibit boosted sensitivity in excitable cells such as neurons and cardiomyocytes. However, the voltage signals recorded during long-term imaging are severely diminished or distorted due to phototoxicity and photobleaching issues. To capture stable electrophysiological activities over a long time, we employ cyanine dyes conjugated with a cyclooctatetraene (COT) molecule as the fluorescence reporter of HVI. The resulting orange-emitting HVI-COT-Cy3 enables high-fidelity voltage imaging for up to 30 min in cultured primary neurons with a sensitivity of ~ -30% ΔF/F0 per action potential (AP). It also maximally preserves the signal of individual APs in cardiomyocytes. The far-red-emitting HVI-COT-Cy5 allows two-color voltage/calcium imaging with GCaMP6s in neurons and cardiomyocytes for 15 min. We leverage the HVI-COT series with reduced phototoxicity and photobleaching to evaluate the impact of drug candidates on the electrophysiology of excitable cells.


Asunto(s)
Dermatitis Fototóxica , Miocitos Cardíacos , Humanos , Neuronas , Diagnóstico por Imagen , Colorantes
2.
Proc Natl Acad Sci U S A ; 120(20): e2302776120, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155861

RESUMEN

Nonexponential relaxations are universal characteristics for glassy materials. There is a well-known hypothesis that nonexponential relaxation peaks are composed of a series of exponential events, which have not been verified. In this Letter, we discover the exponential relaxation events during the recovery process using a high-precision nanocalorimetry, which are universal for metallic glasses and organic glasses. The relaxation peaks can be well fitted by the exponential Debye function with a single activation energy. The activation energy covers a broad range from α relaxation to ß relaxation and even the fast γ/ß' relaxation. We obtain the complete spectrum of the exponential relaxation peaks over a wide temperature range from 0.63Tg to 1.03Tg, which provides solid evidence that nonexponential relaxation peaks can be decomposed into exponential relaxation units. Furthermore, the contribution of different relaxation modes in the nonequilibrium enthalpy space is measured. These results open a door for developing the thermodynamics of nonequilibrium physics and for precisely modulating the properties of glasses by controlling the relaxation modes.

3.
Antimicrob Agents Chemother ; 68(7): e0016824, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38809067

RESUMEN

Zika virus (ZIKV) is one of the mosquito-borne flaviviruses that exhibits a unique tropism to nervous systems and is associated with Guillain-Barre syndrome and congenital Zika syndrome (CZS). Dengue virus (DENV) and yellow fever virus (YFV), the other two mosquito-borne flaviviruses, have also been circulating for a long time and cause severe diseases, such as dengue hemorrhagic fever and yellow fever, respectively. However, there are no safe and effective antiviral drugs approved for the treatment of infections or coinfections of these flaviviruses. Here, we found that zafirlukast, a pregnancy-safe leukotriene receptor antagonist, exhibited potent antiviral activity against infections of ZIKV strains from different lineages in different cell lines, as well as against infections of DENV-2 and YFV 17D. Mechanistic studies demonstrated that zafirlukast directly and irreversibly inactivated these flaviviruses by disrupting the integrity of the virions, leading to the loss of viral infectivity, hence inhibiting the entry step of virus infection. Considering its efficacy against flaviviruses, its safety for pregnant women, and its neuroprotective effect, zafirlukast is a promising candidate for prophylaxis and treatment of infections or coinfections of ZIKV, DENV, and YFV, even in pregnant women.


Asunto(s)
Antivirales , Virus del Dengue , Indoles , Sulfonamidas , Virus de la Fiebre Amarilla , Virus Zika , Virus Zika/efectos de los fármacos , Humanos , Antivirales/farmacología , Virus del Dengue/efectos de los fármacos , Virus del Dengue/genética , Animales , Virus de la Fiebre Amarilla/efectos de los fármacos , Indoles/farmacología , Sulfonamidas/farmacología , Chlorocebus aethiops , Células Vero , Infección por el Virus Zika/tratamiento farmacológico , Infección por el Virus Zika/virología , Línea Celular , Fenilcarbamatos
4.
Antimicrob Agents Chemother ; : e0005424, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687016

RESUMEN

Human enteroviruses are the major pathogens causing hand-foot-and-mouth disease in infants and young children throughout the world, and infection with enterovirus is also associated with severe complications, such as aseptic meningitis and myocarditis. However, there are no antiviral drugs available to treat enteroviruses infection at present. In this study, we found that 4'-fluorouridine (4'-FlU), a nucleoside analog with low cytotoxicity, exhibited broad-spectrum activity against infections of multiple enteroviruses with EC50 values at low micromolar levels, including coxsackievirus A10 (CV-A10), CV-A16, CV-A6, CV-A7, CV-B3, enterovirus A71 (EV-A71), EV-A89, EV-D68, and echovirus 6. With further investigation, the results indicated that 4'-FlU directly interacted with the RNA-dependent RNA polymerase of enterovirus, the 3D pol, and impaired the polymerase activity of 3D pol, hence inhibiting viral RNA synthesis and significantly suppressing viral replication. Our findings suggest that 4'-FlU could be promisingly developed as a broad-spectrum direct-acting antiviral agent for anti-enteroviruses therapy.

5.
Small ; 20(7): e2306800, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37823676

RESUMEN

Thermally activated delayed fluorescence (TADF) materials have been widely studied for the fabrication of high-performance organic light-emitting diodes (OLEDs), but the serious efficiency roll-offs still remain unsolved in most cases. Herein, it is wish to report a series of robust green TADF compounds containing rigid xanthenone acceptor and acridine-based spiro donors. The enhancement in molecular rigidity not only endows the compounds with improved thermal stability but also results in reduced geometric vibrations and thus lowered reorganization energies. These compounds exhibit distinct merits of high thermal stabilities, excellent photoluminescence quantum efficiencies (96%-97%), large horizontal dipole orientation ratios (87.4%-92.1%) and fast TADF rates (1.4-1.5 × 106 s-1 ). The OLEDs using them as emitters furnish superb electroluminescence performances with outstanding external quantum efficiencies (ηext s) of up to 37.4% and very small efficiency roll-offs. Moreover, highly efficient hyperfluorescence OLEDs are obtained by using them as sensitizers for the green mutilresonance TADF emitter BN2, delivering excellent ηext s of up to 34.2% and improved color purity. These results disclose the high potential of these TADF compounds as emitters and sensitizers for OLEDs.

6.
Chemistry ; 30(14): e202303990, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38060300

RESUMEN

Red luminescent materials are essential components for full color display and white lightening based on organic light-emitting diode (OLED) technology, but the extension of emission color towards red or deep red region generally leads to decreased photoluminescence and electroluminescence efficiencies. Herein, we wish to report two new luminescent molecules (2CNDPBPPr-TPA and 4CNDPBPPr-TPA) consisting of cyano-substituted 11,12-diphenyldipyrido[3,2-a:2',3'-c]phenazine acceptors and triphenylamine donors. As the increase of cyano substituents, the emission wavelength is greatly red-shifted and the reverse intersystem crossing process is promoted, resulting in strong red delayed fluorescence. Meanwhile, due to the formation of intramolecular hydrogen bonds, the molecular structures become rigidified and planarized, which brings about large horizontal dipole ratios. As a result, 2CNDPBPPr-TPA and 4CNDPBPPr-TPA can perform as emitters efficiently in OLEDs, furnishing excellent external quantum efficiencies of 28.8 % at 616 nm and 20.2 % at 648 nm, which are significantly improved in comparison with that of the control molecule without cyano substituents. The findings in this work demonstrate that the introduction of cyano substituents to the acceptors of delayed fluorescence molecules could be a facile and effective approach to explore high-efficiency red or deep red delayed fluorescence materials.

7.
Fish Shellfish Immunol ; 145: 109374, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38218422

RESUMEN

As an adaptor protein functions essentially in the activation of NF-κΒ and MAPK signaling pathways mediated by NOD1 and NOD2, RIP2 plays important roles in the host innate immune responses. In the present study, the RIP2 ortholog termed Lc-RIP2 was identified and characterized in large yellow croaker (Larimichthys crocea). It was revealed that Lc-RIP2 is consisted of an open reading frame (ORF) of 1695 bp, encoding a protein of 564 aa, with an N-terminal kinase domain and a C-terminal caspase activation and recruitment domain (CARD). Subcellular localization assays demonstrated that Lc-RIP2 was a cytosolic protein, which was broadly distributed in the examined tissues/organs, and could be induced in response to poly I:C, LPS, PGN, and Pseudomonas plecoglossicida stimulations in vivo according to qRT-PCR analysis. Notably, Lc-RIP2 overexpression in vitro was sufficient to abolish SVCV proliferation in EPC cells, and could significantly induce the activation of NF-κB, IRF3, IRF7, and IFN1 promoters. In addition, luciferase assays found that Lc-RIP2 could cooperate with Lc-MAVS, Lc-TRAF3, Lc-TRAF6, Lc-IRF3, and Lc-IRF7 in NF-κB activation, associate with Lc-TRIF, Lc-MAVS, Lc-TRAF3, Lc-IRF3, and Lc-IRF7 in IRF3 activation, enhance Lc-TRIF, Lc-MAVS, Lc-TRAF3, and Lc-TRAF6 mediated IRF7 activation, and Lc-IRF3 mediated IFN1 activation, whereas suppress NF-κB activation when co-expressed with Lc-TRIF. Co-immunoprecipitation (Co-IP) assays also demonstrated that Lc-RIP2 interacts separately with Lc-TRIF, Lc-MAVS, Lc-TRAF3, Lc-TRAF6, Lc-IRF3, and Lc-IRF7. It is thus collectively indicated that Lc-RIP2 function dominantly in the regulation of the host innate immune signaling.


Asunto(s)
FN-kappa B , Perciformes , Animales , FN-kappa B/metabolismo , Factor 3 Asociado a Receptor de TNF/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Secuencia de Aminoácidos , Inmunidad Innata , Proteínas Adaptadoras del Transporte Vesicular , Antivirales
8.
Mediators Inflamm ; 2024: 8869510, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38445290

RESUMEN

Inflammation is a complex host defensive response against various disease-associated pathogens. A baseline extent of inflammation is supposed to be tightly associated with a sequence of immune-modulated processes, resulting in the protection of the host organism against pathogen invasion; however, as a matter of fact is that an uncontrolled inflammatory cascade is the main factor responsible for the host damage, accordingly suggesting a significant and indispensable involvement of negative feedback mechanism in modulation of inflammation. Evidence accumulated so far has supported a repressive effect of the canonical Wnt/ß-catenin pathway on microbial-triggered inflammation via diverse mechanisms, although that consequence is dependent on the cellular context, types of stimuli, and cytokine environment. It is of particular interest and importance to comprehend the precise way in which the Wnt/ß-catenin pathway is activated, due to its essential anti-inflammatory properties. It is assumed that an inflammatory milieu is necessary for initiating and activating this signaling, implying that Wnt activity is responsible for shielding tissues from overwhelming inflammation, thus sustaining a balanced physiological condition against bacterial infection. This review gathers the recent efforts to elucidate the mechanistic details through how Wnt/ß-catenin signaling modulates anti-inflammatory responses in response to bacterial infection and its interactions with other inflammatory signals, which warrants further study for the development of specific interventions for the treatment of inflammatory diseases. Further clinical trials from different disease settings are required.


Asunto(s)
Infecciones Bacterianas , beta Catenina , Humanos , Bacterias , Vía de Señalización Wnt , Inflamación , Antiinflamatorios
9.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-34135121

RESUMEN

Proteome-wide profiling of protein phosphorylation has been widely used to reveal the underlying mechanism of diverse cellular signaling events. Yet, characterizing subcellular phosphoproteome with high spatial-temporal resolution has remained challenging. Herein, we developed a subcellular-specific uncaging-assisted biotinylation and mapping of phosphoproteome (SubMAPP) strategy to monitor the phosphorylation dynamics of subcellular proteome in living cells and animals. Our method capitalizes on the genetically encoded bioorthogonal decaging strategy, which enables the rapid activation of subcellular localized proximity labeling biotin ligase through either light illumination or small-molecule triggers. By further adopting an integrated orthogonal pull-down strategy with quantitative mass spectrometry, SubMAPP allowed for the investigation of subcellular phosphoproteome dynamics, revealing the altered phosphorylation patterns of endoplasmic reticulum (ER) luminal proteins under ER stress. Finally, we further expanded the scope of the SubMAPP strategy to primary neuron culture and living mice.


Asunto(s)
Fosfoproteínas/metabolismo , Proteómica , Secuencia de Aminoácidos , Animales , Retículo Endoplásmico/metabolismo , Células HEK293 , Humanos , Ratones , Neuronas/metabolismo , Fosfoproteínas/química , Proteoma/metabolismo , Fracciones Subcelulares/metabolismo , Factores de Tiempo
10.
Biochem Genet ; 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38233694

RESUMEN

The aim of this study was to examine the expression changes of H2S, IGF-1, and GH in traumatic brain injury (TBI) patients and to detect their neuroprotective functions after TBI. In this study, we first collected cerebrospinal fluid (CSF) and plasma from TBI patients at different times after injury and evaluated the concentrations of H2S, IGF-1, and GH. In vitro studies were using the scratch-induced injury model and cell-cell interaction model (HT22 hippocampal neurons co-cultured with LPS-induced BV2 microglia cells). In vivo studies were using the controlled cortical impact (CCI) model in mice. Cell viability was assessed by CCK-8 assay. Pro-inflammatory cytokines expression was determined by qRT-PCR, ELISA, and nitric oxide production. Western blot was performed to assess the expression of CBS, CSE, IGF-1, and GHRH. Moreover, the recovery of TBI mice was evaluated for behavioral function by applying the modified Neurological Severity Score (mNSS), the Rotarod test, and the Morris water maze. We discovered that serum H2S, CSF H2S, and serum IGF-1 concentrations were all adversely associated with the severity of the TBI, while the concentrations of IGF-1 and GH in CSF and GH in the serum were all positively related to TBI severity. Experiments in vitro and in vivo indicated that treatment with NaHS (H2S donor), IGF-1, and MR-409 (GHRH agonist) showed protective effects after TBI. This study gives novel information on the functions of H2S, IGF-1, and GH in TBI.

11.
Angew Chem Int Ed Engl ; 63(4): e202316481, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38063138

RESUMEN

Boronate rearrangements, such as the Matteson and Petasis reactions, are valuable metal-free reactions for the transfer of the carbo group on boron to intramolecular electrophilic sites. However, only highly reactive electrophiles are suitable, and ketones are too inactive for those boronate rearrangements due to the high energy barriers. We disclose here the 1,3-boronate rearrangement to ketones, for which a high energy barrier (44.9 kcal/mol) is prohibitory for thermal reactions in the ground state. The reaction is enabled by the key keto-enol-boronate bidentate complex formation in situ, which absorbs visible light to reach the excited state for the chemoselective 1,3-boronate rearrangement to ketones. Experimental and computational investigations exclude free radical intermediates from organoboronates. The aryl, alkenyl, and alkyl boronic acids react with various 1,3-diketones driven by visible light irradiation to construct structurally diverse ß-keto tertiary alcohols under metal-free conditions. The reaction demonstrates substrate diversity with 58 examples, yields up to 98 %, and it is suitable for gram-scale synthesis.

12.
Angew Chem Int Ed Engl ; 63(29): e202405418, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38686901

RESUMEN

Purely organic molecules with room-temperature phosphorescence (RTP) are potential luminescent materials with high exciton utilization for organic light-emitting diodes (OLEDs), but those exhibiting superb electroluminescence (EL) performances are rarely explored, mainly due to their long phosphorescence lifetimes. Herein, a robust purely organic RTP molecule, 3,6-bis(5-phenylindolo[3,2-a]carbazol-12(5H)-yl)-xanthen-9-one (3,2-PIC-XT), is developed. The neat film of 3,2-PIC-XT shows strong green RTP with a very short lifetime (2.9 µs) and a high photoluminescence quantum yield (72 %), and behaviors balanced bipolar charge transport. The RTP nature of 3,2-PIC-XT is validated by steady-state and transient absorption and emission spectroscopies, and the working mechanism is deciphered by theoretical simulation. Non-doped multilayer OLEDs using thin neat films of 3,2-PIC-XT furnish an outstanding external quantum efficiency (EQE) of 24.91 % with an extremely low roll-off (1.6 %) at 1000 cd m-2. High-performance non-doped top-emitting and tandem OLEDs are also achieved, providing remarkable EQEs of 24.53 % and 42.50 %, respectively. Delightfully, non-doped simplified OLEDs employing thick neat films of 3,2-PIC-XT are also realized, furnishing an excellent EQE of 17.79 % and greatly enhanced operational lifetime. The temperature-dependent and transient EL spectroscopies demonstrate the electrophosphorescence attribute of 3,2-PIC-XT. These non-doped OLEDs are the best devices based on purely organic RTP materials reported so far.

13.
Biochemistry ; 62(12): 1844-1848, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37253270

RESUMEN

In eukaryotic cells, the subcellular targeting of RNA controls many fundamental aspects of cellular physiology. Despite broad distributions throughout the cytoplasm, RNA molecules are conventionally believed to be excluded from the secretory pathway compartments including the endoplasmic reticulum (ER). Recent discovery of RNA N-glycan modification (glycoRNAs) has challenged this view, but direct evidence of RNA localization in the ER lumen has been lacking. In this study, we applied enzyme-mediated proximity labeling to profile the ER lumen-localized RNAs in human embryonic kidney 293T cells and rat cortical neurons. Our data set reveals the presence of small non-coding RNAs in the ER lumen, including U RNAs and Y RNAs, which raises interesting questions regarding their transport mechanism and biological functions in the ER.


Asunto(s)
Retículo Endoplásmico , ARN , Ratas , Animales , Humanos , Retículo Endoplásmico/metabolismo , ARN/metabolismo , Neuronas
14.
Chembiochem ; 24(8): e202200745, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-36762434

RESUMEN

Investigating the subcellular organization of biomolecules is important for understanding their biological functions. Over the past decade, proximity-dependent labeling methods have emerged as powerful tools for mapping biomolecules in their native context. These methods often capitalize on the in-situ generation of highly reactive intermediates for covalently tagging biomolecules located within nanometers to sub-micrometers of the source of labeling. Among these, photocatalytic proximity labeling methods achieve precise spatial and temporal control of labeling with visible light illumination. In this review, we summarize the mechanisms and applications of existing photocatalytic proximity labeling methods and discuss future opportunities for improving the method.


Asunto(s)
Luz , Coloración y Etiquetado
15.
J Transl Med ; 21(1): 328, 2023 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-37198593

RESUMEN

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most prevalent and fatal oral cancers. Mitochondria-targeting therapies represent promising strategies against various cancers, but their applications in treating OSCC are limited. Alantolactone (ALT) possesses anticancer properties and also regulates mitochondrial events. In this study, we explored the effects of ALT on OSCC and the related mechanisms. METHODS: The OSCC cells were treated with varying concentrations and duration of ALT and N-Acetyl-L-cysteine (NAC). The cell viability and colony formation were assessed. The apoptotic rate was evaluated by flow cytometry with Annexin V-FITC/PI double staining. We used DCFH-DA and flow cytometry to detect reactive oxygen species (ROS) production and DAF-FM DA to investigate reactive nitrogen species (RNS) level. Mitochondrial function was reflected by mitochondrial reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and ATP levels. KEGG enrichment analyses determined the mitochondrial-related hub genes involved in OSCC progression. Dynamin-related protein 1 (Drp1) overexpression plasmids were further transfected into the cells to analyze the role of Drp1 in OSCC progression. Immunohistochemistry staining and western blot verified the expression of the protein. RESULTS: ALT exerted anti-proliferative and pro-apoptosis effects on OSCC cells. Mechanistically, ALT elicited cell injury by promoting ROS production, mitochondrial membrane depolarization, and ATP depletion, which were reversed by NAC. Bioinformatics analysis showed that Drp1 played a crucial role in OSCC progression. OSCC patients with low Drp1 expression had a higher survival rate. The OSCC cancer tissues presented higher phosphorylated-Drp1 and Drp1 levels than the normal tissues. The results further showed that ALT suppressed Drp1 phosphorylation in OSCC cells. Moreover, Drp1 overexpression abolished the reduced Drp1 phosphorylation by ALT and promoted the cell viability of ALT-treated cells. Drp1 overexpression also reversed the mitochondrial dysfunction induced by ALT, with decreased ROS production, and increased mitochondrial membrane potential and ATP level. CONCLUSIONS: ALT inhibited proliferation and promoted apoptosis of oral squamous cell carcinoma cells via impairment of mitochondrial homeostasis and regulation of Drp1. The results provide a solid basis for ALT as a therapeutic candidate for treating OSCC, with Drp1 being a novel therapeutic target in treating OSCC.


Asunto(s)
Dinaminas , Neoplasias de la Boca , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Adenosina Trifosfato/metabolismo , Apoptosis , Línea Celular Tumoral , Regulación hacia Abajo , Dinaminas/metabolismo , Dinaminas/farmacología , Dinaminas/uso terapéutico , Mitocondrias/metabolismo , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/patología , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/patología
16.
J Med Virol ; 95(4): e28721, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37185862

RESUMEN

The ectodomain of influenza matrix protein 2 (M2e) is a promising target for the development of universal prophylactic and therapeutic agents against influenza viruses of different subtypes. We constructed three M2e-specific monoclonal antibody variants, M2A1-1 (IgG1), M2A1-2a (IgG2a), M2A1-2b (IgG2b), which have the same Fab region targeting the M2e epitope but different isotypes, and compared their protective efficacy in influenza PR8-infected mice. We found that anti-M2e antibodies provided protection against influenza virus in a subtype-dependent manner, with the IgG2a variant providing significantly better protection with lower virus titers and milder lung injury than IgG1 and IgG2b isotypes. Additionally, we observed that the protective efficacy was dependent on the administration routes, with intranasal administration of antibody providing better protection than intraperitoneal administration. The timing of administration was also critical in determining the protective efficacy; while all the antibody isotypes provided protection when administered before influenza challenge, only IgG2a provided minimal protection when the antibodies were administered after virus challenge. These results provide valuable information for optimizing the therapeutics usage of M2e-based antibodies and furthering the development of M2e-based universal influenza vaccines.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Infecciones por Orthomyxoviridae , Orthomyxoviridae , Animales , Ratones , Humanos , Anticuerpos Antivirales , Inmunoglobulina G , Proteínas de la Matriz Viral/genética , Ratones Endogámicos BALB C
17.
Hum Reprod ; 38(6): 1036-1046, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37018627

RESUMEN

STUDY QUESTION: Is sperm telomere length (STL) associated with sperm nuclear DNA damage and mitochondrial DNA abnormalities? SUMMARY ANSWER: Sperm telomere length is related to sperm nuclear DNA integrity and mitochondrial DNA abnormalities in healthy young college students. WHAT IS KNOWN ALREADY: Many studies have revealed the correlations between sperm genetic alterations in both the nucleus and mitochondria and sperm functionality, however, the possible associations between the telomere, an important component of chromosome, and conventional indicators of mitochondrial DNA and nuclear DNA changes have not been investigated. STUDY DESIGN, SIZE, DURATION: A prospective cohort study, Male Reproductive Health in Chongqing College Students (MARHCS), was conducted from June 2013 to June 2015. We pooled data collected from the follow-up study in 2014 and a total of 444 participants were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: STL was measured by quantitative (Q)-PCR. Sperm nuclear DNA integrity was determined using sperm chromatin structure assay (SCSA) and comet assay. Mitochondrial DNA damage was assessed by mitochondrial DNA copy number (mtDNAcn) evaluated with Q-PCR, and mtDNA integrity was determined with long PCR. MAIN RESULTS AND THE ROLE OF CHANCE: The univariable-linear regression analysis revealed that STL was significantly positively correlated with markers of sperm nuclear DNA damage including the DNA fragmentation index (DFI) and comet parameters (the percentage of DNA in the tail, tail length, comet length, and tail moment). Additionally, STL was also significantly positively correlated with mtDNAcn and significantly negatively correlated with mtDNA integrity. After adjustment for potential confounders, these relationships remained appreciable. Moreover, we investigated potential effects of biometric factors, including age, parental age at conception, and BMI on STL and found that STL was increased with paternal age at conception. LIMITATIONS, REASONS FOR CAUTION: A mechanistic explanation of the correlation between STL, sperm nuclear DNA integrity, and mtDNA abnormalities cannot be provided with a cross-sectional study design, so well-designed longitudinal studies are still necessary. In addition, a single semen samples were provided and were not all obtained at the same time point, which may increase the intraindividual bias in this study. WIDER IMPLICATIONS OF THE FINDINGS: The findings extend the literature including assessment of mitochondrial dysfunction, sperm nuclear DNA damage, and telomere length and provide new insights into the relevance of STL in male reproduction. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Science Foundation of China (No. 82073590), the National Natural Science Foundation of China (No. 81903363), the National Natural Science Foundation of China (No. 82130097), and the National Key R&D Program of China (2022YFC2702900). The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
ADN Mitocondrial , Semen , Humanos , Masculino , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Estudios Prospectivos , Estudios de Seguimiento , Estudios Transversales , Espermatozoides/metabolismo , Análisis de Semen , Mitocondrias/genética , Telómero , Estudiantes
18.
Toxicol Appl Pharmacol ; 475: 116656, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37579952

RESUMEN

Telomere and mitochondria may be the targets of Benzo[a]pyrene (BaP) -induced male reproductive damage, and further elucidation of the toxic molecular mechanisms is necessary. In this study, we used in vivo and in vitro exposure models to explore the molecular mechanisms of TERT regulation in BaP-induced telomere and mitochondrial damage in spermatocytes. The results showed that the treatment of benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), the active metabolite of BaP, caused telomere dysfunction in mouse spermatocyte-derived GC-2 cells, resulting in S-phase arrest and increased senescence-associated secretory phenotype (SASP). These effects were significantly alleviated by telomerase agonist (ABG) pretreatment in GC-2 cells. SIRT1, FOXO3a, or c-MYC overexpressing GC-2 cell models were established to demonstrate that BPDE inhibited TERT transcriptional expression through the SIRT1/FOXO3a/c-MYC pathway, leading to telomere dysfunction. We also observed that BPDE induced mitochondrial compromise, including complex I damage, accompanied by reduced mitochondrial TERT expression. Based on this, we constructed wild-type TERT-overexpressing (OE-TERTwt) and mitochondria targeting TERT-overexpressing (OE-TERTmst) GC-2 cell models and found that OE-TERTmst GC-2 cells improved mitochondrial function better than OE-TERTwt GC-2 cells. Finally, ICR mice were given BaP by intragastric administration for 35 days, which verified the results of the in vitro study. The results shown that BaP exposure can lead to spermatogenesis disturbance, which is related to the telomere and mitochondrial damage in spermatocytes. In conclusion, our results suggest that BPDE causes telomere and mitochondrial damage in spermatocytes by inhibiting TERT transcription and mitochondrial TERT expression. This study elucidates the molecular mechanism of male reproductive toxicity due to environmental pollutant BaP, and also provides a new perspective for the exploration of interventions and protective measures against male reproductive damage by BaP.


Asunto(s)
7,8-Dihidro-7,8-dihidroxibenzo(a)pireno 9,10-óxido , Benzo(a)pireno , Ratones , Masculino , Animales , Benzo(a)pireno/toxicidad , Benzo(a)pireno/metabolismo , 7,8-Dihidro-7,8-dihidroxibenzo(a)pireno 9,10-óxido/toxicidad , Espermatocitos , Sirtuina 1/metabolismo , Ratones Endogámicos ICR , Mitocondrias
19.
Chemistry ; 29(1): e202202787, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36196504

RESUMEN

The development of new vinylene-linked covalent organic frameworks (COFs) with special ionic structure and high stability is challenging. Herein, we report a facile, general method for constructing ionic vinylene-linked thiopyrylium-based COFs from 2,4,6-trimethylpyrylium tetrafluoroborate and other common reagents by means of acid-catalyzed Aldol condensation. Besides, pyrylium-, and pyridinium-based COFs also can be prepared from the same monomer under slightly different reaction conditions. The COFs exhibited uniform nanofibrous morphologies with excellent crystallinities, special ionic structures, well-defined nanochannels, and high specific surface areas.

20.
Mol Pharm ; 20(1): 758-766, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36374990

RESUMEN

In this study, the author compared the performance of two allometric scaling approaches and body-weight-based dose conversion approach for first-in-patient (FIP) dose prediction for adeno-associated virus (AAV)-mediated hemophilia gene therapy using preclinical and clinical efficacy data of nine AAV vectors. In general, body-weight-based direct conversion of effective doses in monkeys or dogs was more likely to underestimate FIP dose but worked for one bioengineered vector with a high transduction efficiency specifically in humans. In contrast, allometric scaling between gene efficiency factor (log GEF) and body weight (log W) was likely to overestimate FIP dose but worked for two vectors with capsid-specific T-cell responses in patients. The third approach, allometric scaling between log GEF and W-0.25 was appropriate for FIP dose prediction in the absence of T-cell responses to AAV vectors or a dramatic difference in vector transduction efficiency between animals and humans.


Asunto(s)
Hemofilia A , Humanos , Animales , Perros , Hemofilia A/genética , Hemofilia A/terapia , Dependovirus/genética , Terapia Genética , Cápside , Proteínas de la Cápside/genética , Vectores Genéticos/genética
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