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1.
Nat Protoc ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956381

RESUMEN

Here, we present a protocol for isolating functionally intact glutamatergic synaptic vesicles from whole-mouse brain tissue and using them in a single-vesicle assay to examine their association and fusion with plasma membrane mimic vesicles. This is a Protocol Extension, building on our previous protocol, which used a purely synthetic system comprised of reconstituted proteins in liposomes. We also describe the generation of a peptide based on the vesicular glutamate transporter, which is essential in the isolation process of glutamatergic synaptic vesicles. This method uses easily accessible reagents to generate fusion-competent glutamatergic synaptic vesicles through immunoisolation. The generation of the vGlut peptide can be accomplished in 6 d, while the isolation of the synaptic vesicles by using the peptide can be accomplished in 2 d, with an additional day to fluorescently label the synaptic vesicles for use in a single-vesicle hybrid fusion assay. The single-vesicle fusion assay can be accomplished in 1 d and can unambiguously delineate synaptic vesicle association, dissociation, Ca2+-independent and Ca2+-dependent fusion modalities. This assay grants control of the synaptic vesicle environment while retaining the complexity of the synaptic vesicles themselves. This protocol can be adapted to studies of other types of synaptic vesicles or, more generally, different secretory or transport vesicles. The workflow described here requires expertise in biochemistry techniques, in particular, protein purification and fluorescence imaging. We assume that the laboratory has protein-purification equipment, including chromatography systems.

2.
Nat Cell Biol ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951706

RESUMEN

α-Synuclein (α-Syn) aggregation is closely associated with Parkinson's disease neuropathology. Physiologically, α-Syn promotes synaptic vesicle (SV) clustering and soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex assembly. However, the underlying structural and molecular mechanisms are uncertain and it is not known whether this function affects the pathological aggregation of α-Syn. Here we show that the juxtamembrane region of vesicle-associated membrane protein 2 (VAMP2)-a component of the SNARE complex that resides on SVs-directly interacts with the carboxy-terminal region of α-Syn through charged residues to regulate α-Syn's function in clustering SVs and promoting SNARE complex assembly by inducing a multi-component condensed phase of SVs, α-Syn and other components. Moreover, VAMP2 binding protects α-Syn against forming aggregation-prone oligomers and fibrils in these condensates. Our results suggest a molecular mechanism that maintains α-Syn's function and prevents its pathological amyloid aggregation, the failure of which may lead to Parkinson's disease.

3.
Natl Sci Rev ; 11(6): nwae182, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38962715

RESUMEN

Accumulation of aggregated α-synuclein (α-syn) in Lewy bodies is the pathological hallmark of Parkinson's disease (PD). Genetic mutations in lipid metabolism are causative for a subset of patients with Parkinsonism. The role of α-syn's lipid interactions in its function and aggregation is recognized, yet the specific lipids involved and how lipid metabolism issues trigger α-syn aggregation and neurodegeneration remain unclear. Here, we found that α-syn shows a preference for binding to lysophospholipids (LPLs), particularly targeting lysophosphatidylcholine (LPC) without relying on electrostatic interactions. LPC is capable of maintaining α-syn in a compact conformation, significantly reducing its propensity to aggregate both in vitro and within cellular environments. Conversely, a reduction in the production of cellular LPLs is associated with an increase in α-syn accumulation. Our work underscores the critical role of LPLs in preserving the natural conformation of α-syn to inhibit improper aggregation, and establishes a potential connection between lipid metabolic dysfunction and α-syn aggregation in PD.

4.
BMC Public Health ; 24(1): 1783, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965535

RESUMEN

PURPOSE: To investigate the associations between the most popular social media platform WeChat usage and cognitive performance among the middle-aged and older Chinese population using data from a nationally representative survey. METHODS: In total, 17,472 participants (≥ 45 years old) from the China Health and Retirement Longitudinal Study (CHARLS, Wave 4, 2018) were analyzed. Cognitive performance including episodic memory and executive function was assessed using Mini-Mental Status Examination (MMSE). Other confounding variables included socio-economic characteristics, medical status, and lifestyle-related information. Multiple linear regression models were used to test the association between cognitive performance and WeChat usage by introducing covariates hierarchically. Subgroup analyses of age and gender were conducted to estimate the robustness of the primary findings. RESULTS: After adjusting for multiple confounders across all linear models, WeChat usage is significantly associated with executive function, episodic memory, and global cognitive performance (all p values<0.05). Such results remained robust in subgroup analyses, stratified by age and gender, and also verified according to longitudinal analyses. Compared to 'Chat-only' users who only used WeChat for online interpersonal communication, further usage of WeChat functions such as using 'Moments' appeared to be significantly associated with better cognitive performance, especially for episodic memory. CONCLUSION: Social media usage is significantly and positively associated with better cognitive performance among the middle-aged and older Chinese population. Along with point-to-point messaging, using 'Moments' and extended social media platform functions may correlate to better cognitive performance.


Asunto(s)
Cognición , Medios de Comunicación Sociales , Humanos , Masculino , Femenino , China , Persona de Mediana Edad , Anciano , Estudios Longitudinales , Medios de Comunicación Sociales/estadística & datos numéricos , Función Ejecutiva , Memoria Episódica , Encuestas y Cuestionarios , Pueblos del Este de Asia
5.
Nat Prod Res ; : 1-10, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38824425

RESUMEN

The sciatic nerve is the largest sensorimotor nerve within the peripheral nervous system (PNS), possessing the ability to produce endogenous neurotrophins. Compound nerve action potentials (CNAPs) are regarded as a physiological/pathological indicator to identify nerve activity in signal transduction of the PNS. Astragaloside (AST), a small-molecule saponin purified from Astragalus membranaceus, is widely used to treat chronic disease. Nonetheless, the regulatory effects of AST on the sciatic nerve remain unknown. Therefore, the present investigation was undertaken to study the effect of AST on CNAPs of frog sciatic nerves. Here, AST depressed the conduction velocity and amplitude of CNAPs. Importantly, the AST-induced responses could be blocked by a Ca2+-free medium, or by applying all Ca2+ channel antagonists (CdCl2/LaCl3) or L-type Ca2+ channel blockers (nifedipine/diltiazem), but not the T-type and P-type Ca2+ channel antagonist (NiCl2). Altogether, these findings suggested that AST may attenuate the CNAPs of frog sciatic nerves in vitro via the L-type Ca2+-channel dependent mechanisms.

6.
Nature ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38838737

RESUMEN

Synaptic vesicles are organelles with a precisely defined protein and lipid composition1,2, yet the molecular mechanisms for the biogenesis of synaptic vesicles are mainly unknown. Here, we discovered a well-defined interface between the synaptic vesicle V-ATPase and synaptophysin by in situ cryo-electron tomography and single particle cryo-electron microscopy of functional synaptic vesicles isolated from mouse brains3. The synaptic vesicle V-ATPase is an ATP-dependent proton pump that establishes the protein gradient across the synaptic vesicle, which in turn drives the uptake of neurotransmitters4,5. Synaptophysin6 and its paralogs synaptoporin7 and synaptogyrin8 belong to a family of abundant synaptic vesicle proteins whose function is still unclear. We performed structural and functional studies of synaptophysin knockout mice, confirming the identity of synaptophysin as an interaction partner with the V-ATPase. Although there is little change in the conformation of the V-ATPase upon interaction with synaptophysin, the presence of synaptophysin in synaptic vesicles profoundly affects the copy number of V-ATPases. This effect on the topography of synaptic vesicles suggests that synaptophysin assists in their biogenesis. In support of this model, we observed that synaptophysin knockout mice exhibit severe seizure susceptibility, suggesting an imbalance of neurotransmitter release as a physiological consequence of the absence of synaptophysin.

7.
Front Public Health ; 12: 1371825, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38699422

RESUMEN

Aims: To investigate the association between socioeconomic position (SEP) and sensory impairments (SIs). Methods: We used data from the China Health and Retirement Longitudinal Study (CHARLS) (2015). Logistic regressions estimated the odds ratio for associations of SEP with SIs. In addition, Mendelian randomization (MR) analysis was conducted to assess the causal relationship between them with the inverse variance weighting (IVW) estimator. MR-Egger, simple median, weighted median, maximum likelihood, and robust adjusted profile score were employed for sensitivity analyses. Results: In the observational survey, we enrolled 19,690 individuals aged 45 and above. SEP was negatively associated with SIs. Adjusted odds of vision impairment were higher for illiterate (1.50; 95%CI: 1.19, 1.91), less than elementary school diploma (1.76; 95%CI: 1.39, 2.25), middle school diploma (1.53; 95%CI: 1.21, 1.93) and lower income (all p < 0.001). The odds of hearing impairment were significantly higher for people with less than a high school diploma than those with a college degree or higher diploma, for agricultural workers than non-agricultural workers, and for people in low-income families (p < 0.01). The MR analysis also showed that occupation was associated with HI (1.04, 95%CI: 1.01, 1.09, p < 0.05) using IVW. Conclusion: We found that both observational and causal evidence supports the theory that SEP can result in SIs and that timely discovery, targeted management, and education can prevent SIs among middle-aged and older adults.


Asunto(s)
Análisis de la Aleatorización Mendeliana , Humanos , China/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Longitudinales , Clase Social , Trastornos de la Sensación/epidemiología , Factores Socioeconómicos , Pueblos del Este de Asia
8.
Cell Rep ; 43(5): 114026, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38809756

RESUMEN

Synaptic vesicle docking and priming are dynamic processes. At the molecular level, SNAREs (soluble NSF attachment protein receptors), synaptotagmins, and other factors are critical for Ca2+-triggered vesicle exocytosis, while disassembly factors, including NSF (N-ethylmaleimide-sensitive factor) and α-SNAP (soluble NSF attachment protein), disassemble and recycle SNAREs and antagonize fusion under some conditions. Here, we introduce a hybrid fusion assay that uses synaptic vesicles isolated from mouse brains and synthetic plasma membrane mimics. We included Munc18, Munc13, complexin, NSF, α-SNAP, and an ATP-regeneration system and maintained them continuously-as in the neuron-to investigate how these opposing processes yield fusogenic synaptic vesicles. In this setting, synaptic vesicle association is reversible, and the ATP-regeneration system produces the most synchronous Ca2+-triggered fusion, suggesting that disassembly factors perform quality control at the early stages of synaptic vesicle association to establish a highly fusogenic state. We uncovered a functional role for Munc13 ancillary to the MUN domain that alleviates an α-SNAP-dependent inhibition of Ca2+-triggered fusion.

9.
Curr Res Physiol ; 7: 100121, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38572021

RESUMEN

Synaptic vesicles specific to inhibitory GABA-releasing neurons are critical for regulating neuronal excitability. To study the specific molecular composition, architecture, and function of inhibitory synaptic vesicles, we have developed a new method to isolate and purify GABA synaptic vesicles from mouse brains. GABA synaptic vesicles were immunoisolated from mouse brain tissue using an engineered fragment antigen-binding region (Fab) against the vesicular GABA transporter (vGAT) and purified. Western blot analysis confirmed that the GABA synaptic vesicles were specifically enriched for vGAT and largely depleted of contaminants from other synaptic vesicle types, such as vesicular glutamate transporter (vGLUT1), and other cellular organelles. This degree of purity was achieved despite the relatively low abundance of vGAT vesicles compared to the total synaptic vesicle pool in mammalian brains. Cryo-electron microscopy images of these isolated GABA synaptic vesicles revealed intact morphology with circular shape and protruding proteinaceous densities. The GABA synaptic vesicles are functional, as assessed by a hybrid (ex vivo/in vitro) vesicle fusion assay, and they undergo synchronized fusion with synthetic plasma membrane mimic vesicles in response to Ca2+-triggering, but, as a negative control, not to Mg2+-triggering. Our immunoisolation method could also be applied to other types of vesicles.

10.
Front Pharmacol ; 15: 1375585, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38650627

RESUMEN

The incidence of inflammatory bowel disease (IBD) and the associated risk of colon cancer are increasing globally. Traditional Chinese medicine (TCM) treatment has unique advantages. The Sishen Pill, a common Chinese patented drug used to treat abdominal pain and diarrhea, consists mainly of Psoraleae Fructus, Myristicae Semen, Euodiae Fructus, and Schisandra Chinensis. Modern research has confirmed that Sishen Pill and its active secondary metabolites, such as psoralen, myristicin, evodiamine, and schisandrin, can improve intestinal inflammation and exert antitumor pharmacological effects. Common mechanisms in treating IBD and colon cancer mainly include regulating inflammation-related signaling pathways such as nuclear factor-kappa B, mitogen-activated protein kinase, phosphatidylinositol 3-kinase, NOD-like receptor heat protein domain-related protein 3, and wingless-type MMTV integration site family; NF-E2-related factor 2 and hypoxia-inducible factor 1α to inhibit oxidative stress; mitochondrial autophagy and endoplasmic reticulum stress; intestinal immune cell differentiation and function through the Janus kinase/signal transducer and activator of transcription pathway; and improving the gut microbiota and intestinal barrier. Overall, existing evidence suggests the potential of the Sishen pill to improve IBD and suppress inflammation-to-cancer transformation. However, large-scale randomized controlled clinical studies and research on the safety of these clinical applications are urgently required.

11.
bioRxiv ; 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38496494

RESUMEN

Post-translational modifications (PTMs) of α-synuclein (α-syn) such as acetylation and phosphorylation play important yet distinct roles in regulating α-syn conformation, membrane binding, and amyloid aggregation. However, how PTMs regulate α-syn function in presynaptic terminals remains unclear. Previously, we reported that α-syn clusters synaptic vesicles (SV) 1, and neutral phospholipid lysophosphatidylcholine (LPC) can mediate this clustering 2. Here, based on our previous findings, we further demonstrate that N-terminal acetylation, which occurs under physiological condition and is irreversible in mammalian cells, significantly enhances the functional activity of α-syn in clustering SVs. Mechanistic studies reveal that this enhancement is caused by the N-acetylation-promoted insertion of α-syn's N-terminus and increased intermolecular interactions on the LPC-containing membrane. Our work demonstrates that N-acetylation fine-tunes α-syn-LPC interaction for mediating α-syn's function in SV clustering.

12.
Small ; 20(22): e2309900, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38312091

RESUMEN

All-hydrogel supercapacitors are emerging as promising power sources for next-generation wearable electronics due to their intrinsic mechanical flexibility, eco-friendliness, and enhanced safety. However, the insufficient interfacial adhesion between the electrode and electrolyte and the frozen hydrogel matrices at subzero temperatures largely limit the practical applications of all-hydrogel supercapacitors. Here, an all-hydrogel supercapacitor is reported with robust interfacial contact and anti-freezing property, fabricated by in situ polymerizing hydrogel electrolyte onto hydrogel electrodes. The robust interfacial adhesion is developed by the synergistic effect of a tough hydrogel matrix and topological entanglements. Meanwhile, the incorporation of zinc chloride (ZnCl2) in the hydrogel electrolyte prevents the freezing of water solvents and endows the all-hydrogel supercapacitor with mechanical flexibility and fatigue resistance across a wide temperature range of 20 °C to -60 °C. Such all-hydrogel supercapacitor demonstrates satisfactory low-temperature electrochemical performance, delivering a high energy density of 11 mWh cm-2 and excellent cycling stability with a capacitance retention of 90% over 10000 cycles at -40 °C. Notably, the fabricated all-hydrogel supercapacitor can endure dynamic deformations and operate well under 2000 tension cycles even at -40 °C, without experiencing delamination and electrochemical failure. This work offers a promising strategy for flexible energy storage devices with low-temperature adaptability.

13.
J Ethnopharmacol ; 324: 117733, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38218504

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Ginger is a "medicine-food homology" natural herb and has a longstanding medicinal background in treating intestinal diseases. Its remarkable bioactivities, including anti-inflammatory, antioxidant, immunoregulatory, flora regulatory, intestinal protective, and anticancer properties, make it a promising natural medicine for colorectal cancer (CRC) prevention and treatment. AIM OF THE REVIEW: The purpose is to review the relevant literature on ginger and pharmacodynamic components for CRC prevention and treatment, summarize the possible mechanisms of ginger from clinical studies and animal and in vitro experiments, to provide theoretical support for the use of ginger preparations in the daily prevention and clinical treatment of CRC. MATERIALS AND METHODS: Literatures about ginger and CRC were searched from electronic databases, such as PubMed, Web of Science, ScienceDirect, Google Scholar and China National Knowledge Infrastructure (CNKI). RESULTS: This article summarizes the molecular mechanisms of ginger and its pharmacodynamic components in the prevention and treatment of CRC, including anti-inflammatory, antioxidant, immunoregulatory, flora regulatory, intestinal protective, inhibit CRC cell proliferation, induce CRC cell cycle blockage, promote CRC cell apoptosis, suppress CRC cell invasion and migration, enhance the anticancer effect of chemotherapeutic drugs. CONCLUSIONS: Ginger has potential for daily prevention and clinical treatment of CRC.


Asunto(s)
Neoplasias Colorrectales , Zingiber officinale , Animales , Antioxidantes/farmacología , Intestinos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/prevención & control , Neoplasias Colorrectales/metabolismo , Antiinflamatorios/uso terapéutico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Extractos Vegetales/química
14.
Nat Biomed Eng ; 8(1): 11-29, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36658343

RESUMEN

Current healthcare practices are reactive and use limited physiological and clinical information, often collected months or years apart. Moreover, the discovery and profiling of blood biomarkers in clinical and research settings are constrained by geographical barriers, the cost and inconvenience of in-clinic venepuncture, low sampling frequency and the low depth of molecular measurements. Here we describe a strategy for the frequent capture and analysis of thousands of metabolites, lipids, cytokines and proteins in 10 µl of blood alongside physiological information from wearable sensors. We show the advantages of such frequent and dense multi-omics microsampling in two applications: the assessment of the reactions to a complex mixture of dietary interventions, to discover individualized inflammatory and metabolic responses; and deep individualized profiling, to reveal large-scale molecular fluctuations as well as thousands of molecular relationships associated with intra-day physiological variations (in heart rate, for example) and with the levels of clinical biomarkers (specifically, glucose and cortisol) and of physical activity. Combining wearables and multi-omics microsampling for frequent and scalable omics may facilitate dynamic health profiling and biomarker discovery.


Asunto(s)
Multiómica , Biomarcadores
15.
Genes (Basel) ; 14(12)2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38136987

RESUMEN

The rice leaf folder, Cnaphalocrocis medinalis (Lepidoptera: Pyralidae), is a notorious pest of rice in Asia. The larvae and adults of C. medinalis utilize specialized chemosensory systems to adapt to different environmental odors and physiological behaviors. However, the differences in chemosensory genes between the olfactory organs of these two different developmental stages remain unclear. Here, we conducted a transcriptome analysis of larvae heads, male antennae, and female antennae in C. medinalis and identified 131 putative chemosensory genes, including 32 OBPs (8 novel OBPs), 23 CSPs (2 novel CSPs), 55 ORs (17 novel ORs), 19 IRs (5 novel IRs) and 2 SNMPs. Comparisons between larvae and adults of C. medinalis by transcriptome and RT-qPCR analysis revealed that the number and expression of chemosensory genes in larval heads were less than that of adult antennae. Only 17 chemosensory genes (7 OBPs and 10 CSPs) were specifically or preferentially expressed in the larval heads, while a total of 101 chemosensory genes (21 OBPs, 9 CSPs, 51 ORs, 18 IRs, and 2 SNMPs) were specifically or preferentially expressed in adult antennae. Our study found differences in chemosensory gene expression between larvae and adults, suggesting their specialized functions at different developmental stages of C. medinalis. These results provide a theoretical basis for screening chemosensory genes as potential molecular targets and developing novel management strategies to control C. medinalis.


Asunto(s)
Mariposas Nocturnas , Transcriptoma , Animales , Femenino , Masculino , Transcriptoma/genética , Larva/genética , Perfilación de la Expresión Génica , Mariposas Nocturnas/genética , Asia
16.
Nanomicro Lett ; 16(1): 22, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37982913

RESUMEN

Solid-state zinc-ion capacitors are emerging as promising candidates for large-scale energy storage owing to improved safety, mechanical and thermal stability and easy-to-direct stacking. Hydrogel electrolytes are appealing solid-state electrolytes because of eco-friendliness, high conductivity and intrinsic flexibility. However, the electrolyte/electrode interfacial contact and anti-freezing properties of current hydrogel electrolytes are still challenging for practical applications of zinc-ion capacitors. Here, we report a class of hydrogel electrolytes that couple high interfacial adhesion and anti-freezing performance. The synergy of tough hydrogel matrix and chemical anchorage enables a well-adhered interface between hydrogel electrolyte and electrode. Meanwhile, the cooperative solvation of ZnCl2 and LiCl hybrid salts renders the hydrogel electrolyte high ionic conductivity and mechanical elasticity simultaneously at low temperatures. More significantly, the Zn||carbon nanotubes hybrid capacitor based on this hydrogel electrolyte exhibits low-temperature capacitive performance, delivering high-energy density of 39 Wh kg-1 at -60 °C with capacity retention of 98.7% over 10,000 cycles. With the benefits of the well-adhered electrolyte/electrode interface and the anti-freezing hydrogel electrolyte, the Zn/Li hybrid capacitor is able to accommodate dynamic deformations and function well under 1000 tension cycles even at -60 °C. This work provides a powerful strategy for enabling stable operation of low-temperature zinc-ion capacitors.

17.
Proc Natl Acad Sci U S A ; 120(44): e2310174120, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37883437

RESUMEN

α-synuclein (α-Syn) is a presynaptic protein that is involved in Parkinson's and other neurodegenerative diseases and binds to negatively charged phospholipids. Previously, we reported that α-Syn clusters synthetic proteoliposomes that mimic synaptic vesicles. This vesicle-clustering activity depends on a specific interaction of α-Syn with anionic phospholipids. Here, we report that α-Syn surprisingly also interacts with the neutral phospholipid lysophosphatidylcholine (lysoPC). Even in the absence of anionic lipids, lysoPC facilitates α-Syn-induced vesicle clustering but has no effect on Ca2+-triggered fusion in a single vesicle-vesicle fusion assay. The A30P mutant of α-Syn that causes familial Parkinson disease has a reduced affinity to lysoPC and does not induce vesicle clustering. Taken together, the α-Syn-lysoPC interaction may play a role in α-Syn function.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Vesículas Sinápticas/metabolismo , Lisofosfatidilcolinas/metabolismo , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Fosfolípidos/metabolismo
18.
Nat Biomed Eng ; 2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37620621

RESUMEN

Tracking and imaging immune cells in vivo non-invasively would offer insights into the immune responses induced by vaccination. Here we report a cancer vaccine consisting of polymer-coated NaErF4/NaYF4 core-shell down-conversion nanoparticles emitting luminescence in the near-infrared spectral window IIb (1,500-1,700 nm in wavelength) and with surface-conjugated antigen (ovalbumin) and electrostatically complexed adjuvant (class-B cytosine-phosphate-guanine). Whole-body wide-field imaging of the subcutaneously injected vaccine in tumour-bearing mice revealed rapid migration of the nanoparticles to lymph nodes through lymphatic vessels, with two doses of the vaccine leading to the complete eradication of pre-existing tumours and to the prophylactic inhibition of tumour growth. The abundance of antigen-specific CD8+ T lymphocytes in the tumour microenvironment correlated with vaccine efficacy, as we show via continuous-wave imaging and lifetime imaging of two intravenously injected near-infrared-emitting probes (CD8+-T-cell-targeted NaYbF4/NaYF4 nanoparticles and H-2Kb/ovalbumin257-264 tetramer/PbS/CdS quantum dots) excited at different wavelengths, and by volumetrically visualizing the three nanoparticles via light-sheet microscopy with structured illumination. Nanoparticle-based vaccines and imaging probes emitting infrared light may facilitate the design and optimization of immunotherapies.

19.
Proc Natl Acad Sci U S A ; 120(13): e2300360120, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36940324

RESUMEN

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) introduced a relatively large number of mutations, including three mutations in the highly conserved heptad repeat 1 (HR1) region of the spike glycoprotein (S) critical for its membrane fusion activity. We show that one of these mutations, N969K induces a substantial displacement in the structure of the heptad repeat 2 (HR2) backbone in the HR1HR2 postfusion bundle. Due to this mutation, fusion-entry peptide inhibitors based on the Wuhan strain sequence are less efficacious. Here, we report an Omicron-specific peptide inhibitor designed based on the structure of the Omicron HR1HR2 postfusion bundle. Specifically, we inserted an additional residue in HR2 near the Omicron HR1 K969 residue to better accommodate the N969K mutation and relieve the distortion in the structure of the HR1HR2 postfusion bundle it introduced. The designed inhibitor recovers the loss of inhibition activity of the original longHR2_42 peptide with the Wuhan strain sequence against the Omicron variant in both a cell-cell fusion assay and a vesicular stomatitis virus (VSV)-SARS-CoV-2 chimera infection assay, suggesting that a similar approach could be used to combat future variants. From a mechanistic perspective, our work suggests the interactions in the extended region of HR2 may mediate the initial landing of HR2 onto HR1 during the transition of the S protein from the prehairpin intermediate to the postfusion state.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas del Envoltorio Viral/genética , Secuencia de Aminoácidos , Estructura Secundaria de Proteína , Glicoproteína de la Espiga del Coronavirus/metabolismo , Péptidos/genética , Péptidos/farmacología , Péptidos/química , Antirretrovirales
20.
J Biochem Mol Toxicol ; 37(6): e23329, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36808658

RESUMEN

Doxorubicin (DOX), is a high efficiency anthracycline antitumor drug. However, the clinical application of DOX is limited mainly by dose-related adverse drug reactions. Currently, the therapeutic effects of Atorvastatin (ATO) on DOX-induced hepatotoxicity were studied in vivo. The results indicated that DOX impaired hepatic function, as measured by an increased levels of liver weight index and serum concentrations of aspartate transaminase and alanine transaminase, as well as alteration of hepatic histology. In addition, DOX increased the serum levles of triglyceride (TG) and nonestesterified fatty acid. ATO prevented these changes. Mechanical analysis revealed that ATO restored the changes of malondialdehyde, reactive oxygen radical species, glutathione peroxidase and manganese superoxide dismutase. Additionally, ATO inhibited the increased expression levels of nuclear factor-kappa B and interleukin 1ß, hence suppressing inflammation. Meanwhile, ATO inhibited cell apoptosis by dramatically decreasing the Bax/Bcl-2 ratio. In addition, ATO mitigated the lipidtoxicity by inhibiting the adipolysis of TG and accelerating hepatic lipid metabolism. Taken together, the results suggest ATO has therapeutic effect on DOX-induced hepatotoxicity via inhibition of oxidative damage, inflammatory and apoptosis. In addition, ATO attenuates DOX-induced hyperlipidemia via modulation of lipid metabolism.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Ratas , Animales , Antioxidantes/farmacología , Antioxidantes/metabolismo , Atorvastatina/farmacología , Doxorrubicina/toxicidad , Estrés Oxidativo , Antiinflamatorios/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Apoptosis
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