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1.
Zool Res ; 45(3): 601-616, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38766744

RESUMO

Meiosis is a highly complex process significantly influenced by transcriptional regulation. However, studies on the mechanisms that govern transcriptomic changes during meiosis, especially in prophase I, are limited. Here, we performed single-cell ATAC-seq of human testis tissues and observed reprogramming during the transition from zygotene to pachytene spermatocytes. This event, conserved in mice, involved the deactivation of genes associated with meiosis after reprogramming and the activation of those related to spermatogenesis before their functional onset. Furthermore, we identified 282 transcriptional regulators (TRs) that underwent activation or deactivation subsequent to this process. Evidence suggested that physical contact signals from Sertoli cells may regulate these TRs in spermatocytes, while secreted ENHO signals may alter metabolic patterns in these cells. Our results further indicated that defective transcriptional reprogramming may be associated with non-obstructive azoospermia (NOA). This study revealed the importance of both physical contact and secreted signals between Sertoli cells and germ cells in meiotic progression.


Assuntos
Comunicação Celular , Meiose , Animais , Masculino , Camundongos , Meiose/fisiologia , Humanos , Células de Sertoli/metabolismo , Células de Sertoli/fisiologia , Testículo/metabolismo , Testículo/citologia , Espermatogênese/fisiologia , Regulação da Expressão Gênica , Azoospermia/genética , Transcrição Gênica , RNA Citoplasmático Pequeno/genética , RNA Citoplasmático Pequeno/metabolismo , Análise da Expressão Gênica de Célula Única
2.
Cell Death Differ ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594444

RESUMO

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor characterized by a highly heterogeneous and immunosuppressive tumor microenvironment (TME). The symbiotic interactions between glioblastoma stem cells (GSCs) and tumor-associated macrophages (TAM) in the TME are critical for tumor progression. Here, we identified that IFI35, a transcriptional regulatory factor, plays both cell-intrinsic and cell-extrinsic roles in maintaining GSCs and the immunosuppressive TME. IFI35 induced non-canonical NF-kB signaling through proteasomal processing of p105 to the DNA-binding transcription factor p50, which heterodimerizes with RELB (RELB/p50), and activated cell chemotaxis in a cell-autonomous manner. Further, IFI35 induced recruitment and maintenance of M2-like TAMs in TME in a paracrine manner. Targeting IFI35 effectively suppressed in vivo tumor growth and prolonged survival of orthotopic xenograft-bearing mice. Collectively, these findings reveal the tumor-promoting functions of IFI35 and suggest that targeting IFI35 or its downstream effectors may provide effective approaches to improve GBM treatment.

3.
Org Lett ; 26(15): 3004-3009, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38573817

RESUMO

A well-defined Ru(II)-PNP complex demonstrated high activity in the anti-Markovnikov hydroalkylation of nonpolarized terminal alkenes via hydrazones. Hydrazone served as a carbanion equivalent to combine with the electrophilic alkene substrate upon activation by the ruthenium catalyst, forming a new C-C bond in a concerted pathway with N2 as the only theoretical byproduct. Experimental and computational studies suggested the existence of a push-pull interaction that activated the alkene for hydrazone addition and then deduced the mechanism.

4.
J Genet Genomics ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38479452

RESUMO

In mammals, the neonatal heart can regenerate upon injury within a short time after birth, while adults lose this ability. Metabolic reprogramming has been demonstrated to be critical for cardiomyocyte proliferation in the neonatal heart. Here, we reveal that cardiac metabolic reprogramming could be regulated by altering global protein lactylation. By performing 4D label-free proteomics and lysine lactylation (Kla) omics analyses in mouse hearts at postnatal days 1, 5, and 7, 2297 Kla sites from 980 proteins are identified, among which 1262 Kla sites from 409 proteins are quantified. Functional clustering analysis reveals that the proteins with altered Kla sites are mainly involved in metabolic processes. The expression and Kla levels of proteins in glycolysis show a positive correlation while a negative correlation in fatty acid oxidation. Furthermore, we verify the Kla levels of several differentially modified proteins, including ACAT1, ACADL, ACADVL, PFKM, PKM, and NPM1. Overall, our study reports a comprehensive Kla map in the neonatal mouse heart, which will help to understand the regulatory network of metabolic reprogramming and cardiac regeneration.

5.
Chem Sci ; 15(11): 3831-3871, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38487228

RESUMO

In the vast majority of top-selling pharmaceutical and industrial products, phenolic structural motifs are highly prevalent. Non-functionalized simple phenols serve as building blocks in the synthesis of value-added chemicals. It is worth mentioning that lignin, being the largest renewable biomass source of aromatic building blocks in nature, mainly consists of phenolic units, which enable the production of structurally diverse phenols. Given their remarkable applicability in the chemical value chain, many efforts have been devoted to increasing the molecular complexity of the phenolic scaffold. Among the key techniques, direct functionalization of Csp2-H is a powerful tool, enabling the construction of new Csp2-C bonds in an economical and atomic manner. Herein we present and summarize the large plethora of direct Csp2-H functionalization methods that enables scaffold diversification of simple, unprotected phenols, leading to the formation of new Csp2-C bonds. In this review article, we intend to summarize the contributions that appeared in the literature mainly in the last 5 years dealing with the functionalization of unprotected phenols, both catalytic and non-catalytic. Our goal is to highlight the key findings and the ongoing challenges in the stimulating and growing research dedicated to the development of new protocols for the valorization of phenols.

6.
Chem Sci ; 15(10): 3552-3561, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38455022

RESUMO

One of the most widely utilized methods for the construction of C(sp2)-N bonds is the transition-metal-catalyzed cross-coupling of aryl halides/boronic acids with amines, known as Ullmann condensation, Buchwald-Hartwig amination, and Chan-Lam coupling. However, aryl halides/boronic acids often require multi-step preparation while generating a large amount of corrosive and toxic waste, making the reaction less attractive. Herein, we present an unprecedented method for the C(sp2)-N formation via Buchwald-Hartwig-type reactions using synthetically upstream nitroarenes as the sole starting materials, thus eliminating the need for arylhalides and pre-formed arylamines. A diverse range of symmetrical di- and triarylamines were obtained in a single step from nitroarenes, and more importantly, various unsymmetrical di- and triarylamines were also highly selectively synthesized in a one-pot/two-step process. Furthermore, the success of the scale-up experiments, the late-stage functionalization of a drug intermediate, and the rapid preparation of hole-transporting material TCTA showcased the utility and practicality of this protocol in synthetic chemistry. Mechanistic studies indicate that this transformation may proceed via an arylamine intermediate generated in situ from the reduction of nitroarenes, which is followed by a denitrative Buchwald-Hartwig-type reaction with another nitroarene to form a C-N bond.

7.
Chem Commun (Camb) ; 60(21): 2926-2929, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38372183

RESUMO

This article introduces a reductive coupling driven by visible-light, facilitating the synthesis of pyridine-substituted alcohols and amines through the reaction of aldehydes, ketones and imines with cyanopyridines. Hantzsch esters serve as reductants in this process, eliminating the need for transition-metals or photosensitizers. The method demonstrates extensive compatibility and finds utility in the late-stage functionalization of both natural and pharmaceutical products, offering a sustainable pathway for the diversification of chemical compounds.

8.
Medicine (Baltimore) ; 103(7): e35849, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363951

RESUMO

Acute coronary syndrome (ACS) is one of the most common and severe forms of cardiovascular disease and has attracted worldwide attention with increased morbidity and mortality in recent years. There are few review studies in the field of its care in the form of bibliometric studies. We searched the Web of Science Core Collection database for articles and reviews in the area of ACS nursing for visual mapping analysis. Our objectives are to explore the hot topics and frontiers of research in the field of ACS nursing and to identify collaborative relationships between countries, institutions, and authors. This study will provide researchers with intuitive reference data for future in-depth studies of ACSs.


Assuntos
Síndrome Coronariana Aguda , Humanos , Bibliometria , Bases de Dados Factuais , Pesquisadores
9.
J Am Chem Soc ; 146(4): 2583-2592, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38232387

RESUMO

Catalytic electron donor-acceptor (EDA) complexes have recently emerged as a powerful and sustainable alternative to iridium- and ruthenium-based photoredox synthetic methods. Yet, these complexes remain underexplored and reliant on the use of meticulously designed acceptors that require previous installation. Herein, we report a novel EDA complex employing tris(4-methoxyphenyl) amine as a catalytic donor for the sulfonylation of alkenes using inexpensive and readily available sulfonyl chlorides. Applying this operationally simple, visible-light-mediated general platform, we report both the redox-neutral and net-reductive functionalization of more than 60 substrates, encompassing vinylic or allylic sulfonylation, hydrosulfonylation, and sulfamoylation of activated and unactivated alkenes and alkynes.

10.
J Biol Chem ; 300(2): 105617, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176653

RESUMO

Liver can sense the nutrient status and send signals to other organs to regulate overall metabolic homoeostasis. Herein, we demonstrate that ketone bodies act as signals released from the liver that specifically determine the distribution of excess lipid in epididymal white adipose tissue (eWAT) when exposed to a ketogenic diet (KD). An acute KD can immediately result in excess lipid deposition in the liver. Subsequently, the liver sends the ketone body ß-hydroxybutyrate (BHB) to regulate white adipose expansion, including adipogenesis and lipogenesis, to alleviate hepatic lipid accumulation. When ketone bodies are depleted by deleting 3-hydroxy-3-methylglutaryl-CoA synthase 2 gene in the liver, the enhanced lipid deposition in eWAT but not in inguinal white adipose tissue is preferentially blocked, while lipid accumulation in liver is not alleviated. Mechanistically, ketone body BHB can significantly decrease lysine acetylation of peroxisome proliferator-activated receptor gamma in eWAT, causing enhanced activity of peroxisome proliferator-activated receptor gamma, the key adipogenic transcription factor. These observations suggest that the liver senses metabolic stress first and sends a corresponding signal, that is, ketone body BHB, to specifically promote eWAT expansion to adapt to metabolic challenges.


Assuntos
Tecido Adiposo Branco , Dieta Cetogênica , Fígado Gorduroso , Corpos Cetônicos , Humanos , Tecido Adiposo Branco/metabolismo , Fígado Gorduroso/metabolismo , Corpos Cetônicos/metabolismo , Lipídeos , Fígado/metabolismo , PPAR gama/metabolismo
11.
Cell Prolif ; 57(2): e13551, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37743695

RESUMO

Busulfan is an antineoplastic, which is always accompanied with the abnormal of spermatogonia self-renewal and differentiation. It has been demonstrated that the omega-3 polyunsaturated fatty acids (PUFAs) benefits mature spermatozoa. However, whether omega-3 can protect endogenous spermatogonia and the detailed mechanisms are still unclear. Evaluate of spermatogenesis function (in vivo) were examined by histopathological analysis, immunofluorescence staining, and western blotting. The levels of lipid metabolites in testicular tissue were determined via liquid chromatography. We investigated the effect of lipid metabolites on Sertoli cells provided paracrine factors to regulate spermatogonia proliferation and differentiation using co-culture system. In our study, we showed that omega-3 PUFAs significantly improved the process of sperm production and elevated the quantity of both undifferentiated Lin28+ spermatogonia and differentiated c-kit+ spermatogonia in a mouse model where spermatogenic function was disrupted by busulfan. Mass spectrometry revealed an increase in the levels of several omega-3 metabolites in the testes of mice fed with omega-3 PUFAs. The eicosapentaenoic acid metabolite 12-hydroxyeicosapentaenoic acid (12-HEPE) up-regulated bone morphogenic protein 4 (BMP4) expression through GPR120-ERK1/2 pathway activation in Sertoli cells and restored spermatogonia proliferation and differentiation. Our study provides evidence that omega-3 PUFAs metabolite 12-HEPE effectively protects spermatogonia and reveals that GPR120 might be a tractable pharmacological target for fertility in men received chemotherapy or severe spermatogenesis dysfunction.


Assuntos
Bussulfano , Sêmen , Humanos , Masculino , Camundongos , Animais , Bussulfano/farmacologia , Bussulfano/metabolismo , Espermatogênese/fisiologia , Espermatogônias , Espermatozoides , Testículo/metabolismo
12.
Chem Sci ; 14(42): 11761-11767, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37920336

RESUMO

The direct functionalization of inert C-H bonds has long been a "holy grail" for the chemistry world. In this report, the direct C(sp3)-N bond formation of unactivated alkanes is reported with a GaN based Mott-Schottky catalyst under photocatalytic reaction conditions. Long term stability and reaction efficiency (up to 92%) were achieved with this photocatalyst. The deposition of a Pd co-catalyst on the surface of GaN significantly enhanced the reaction efficiency. Microscopic investigation suggested a remarkable interaction in the Pd/GaN Schottky junction, giving a significant Pd/GaN depletion layer. In addition, density functional theory (DFT) calculations were performed to show the distinct performance of Pd nanoparticles at the atomic level.

13.
Precis Chem ; 1(7): 437-442, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37771514

RESUMO

The decarboxylative Minisci reaction is a versatile tool for the direct C-H alkylation of heteroarenes, where stoichiometric amounts of oxidants or expensive, precious metal reagents are commonly used. Herein, we reported a photodriven decarboxylative Minisci reaction enabled by a gallium nitride-based heterogeneous photocatalyst under mild conditions. This method can be effectively applied to a broad substrate scope of acids, including primary, secondary, and tertiary carboxylic acids and N-heteroarenes effectively. The practicability and robustness of the approach are demonstrated for the functionalization of biologically active compounds.

14.
Mol Reprod Dev ; 90(10-11): 774-781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37733694

RESUMO

Male fertility declines with age. The mevalonate pathway, through which cholesterol and nonsteroidal isoprenoids are synthesized, plays key role in metabolic processes and is an essential pathway for cholesterol production and protein prenylation. Male reproductive aging is accompanied by dramatic changes in the metabolic microenvironment of the testis. Since the mevalonate pathway has an important role in spermatogenesis, we attempted to explore the association between male reproductive aging and the mevalonate pathway to explain the mechanism of male reproductive aging. Alterations in the mevalonate pathway may affect male reproductive aging by decreasing cholesterol synthesis and altering testis protein prenylation. Decreased cholesterol levels affect cholesterol modification, testosterone production, and remodeling of germ cell membranes. Aging-related metabolic disorders also affect the metabolic coupling between somatic cells and spermatogenic cells, leading to male fertility decline. Therefore, we hypothesized that alterations in the mevalonate pathway represent one of the metabolic causes of reproductive aging.


Assuntos
Colesterol , Ácido Mevalônico , Masculino , Humanos , Ácido Mevalônico/metabolismo , Colesterol/metabolismo , Reprodução , Testículo/metabolismo
15.
STAR Protoc ; 4(3): 102530, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37656629

RESUMO

Herein, we present a protocol for the on-demand preparation of methanol and formic acid via selective photo-oxidation of methane with H2O and O2 catalyzed by GaN. The detailed photosyntheses of methanol or formic acid from CH4/H2O or CH4/H2O/O2 are described, respectively. In addition, we provide experimental details for the accurate quantifications of the final gas/liquid products and photoexcited oxygenated radicals. Finally, we deliver the procedure for scaling up the transformation. For complete details on the use and execution of this protocol, please refer to Han et al. (2023).1.


Assuntos
Formiatos , Metanol , Metano
16.
Commun Chem ; 6(1): 181, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658203

RESUMO

Alkanes are naturally abundant chemical building blocks that contain plentiful C(sp3)-H bonds. While inert, the activation of C(sp3)-H via hydrogen atom abstraction (HAT) stages an appealing approach to generate alkyl radicals. However, prevailing shortcomings include the excessive use of oxidants and alkanes that impede scope. We herein show the use of gallium nitride (GaN) as a non-toxic, recyclable, heterogeneous photocatalyst to enable alkyl C(sp3)-H in conjunction with the catalytic use of simple photosensitizer, benzophenone, to promote the desired alkyl radical generation. The dual photocatalytic cycle enables cross-dehydrogenative Minisci alkylation under mild and chemical oxidant-free conditions.

17.
J Biol Chem ; 299(10): 105183, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37611828

RESUMO

Emerging research and clinical evidence suggest that the metabolic activity of oocytes may play a pivotal role in reproductive anomalies. However, the intrinsic mechanisms governing oocyte development regulated by metabolic enzymes remain largely unknown. Our investigation demonstrates that geranylgeranyl diphosphate synthase1 (Ggps1), the crucial enzyme in the mevalonate pathway responsible for synthesizing isoprenoid metabolite geranylgeranyl pyrophosphate from farnesyl pyrophosphate, is essential for oocyte maturation in mice. Our findings reveal that the deletion of Ggps1 that prevents protein prenylation in fully grown oocytes leads to subfertility and offspring metabolic defects without affecting follicle development. Oocytes that lack Ggps1 exhibit disrupted mitochondrial homeostasis and the mitochondrial defects arising from oocytes are inherited by the fetal offspring. Mechanistically, the excessive farnesylation of mitochondrial ribosome protein, Dap3, and decreased levels of small G proteins mediate the mitochondrial dysfunction induced by Ggps1 deficiency. Additionally, a significant reduction in Ggps1 levels in oocytes is accompanied by offspring defects when females are exposed to a high-cholesterol diet. Collectively, this study establishes that mevalonate pathway-protein prenylation is vital for mitochondrial function in oocyte maturation and provides evidence that the disrupted protein prenylation resulting from an imbalance between farnesyl pyrophosphate and geranylgeranyl pyrophosphate is the major mechanism underlying impairment of oocyte quality induced by high cholesterol.

18.
Dev Cell ; 58(21): 2376-2392.e6, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37643613

RESUMO

Embryo implantation requires temporospatial maternal-embryonic dialog. Using single-cell RNA sequencing for the uterus from 2.5 to 4.5 days post-coitum (DPC) and bulk sequencing for the corresponding embryos of 3.5 and 4.0 DPC pregnant mice, we found that estrogen-responsive luminal epithelial cells (EECs) functionally differentiated into adhesive epithelial cells (AECs) and supporting epithelial cells (SECs), promoted by progesterone. Along with maternal signals, embryonic Pdgfa and Efna3/4 signaling activated AECs and SECs, respectively, enhancing the attachment of embryos to the endometrium and furthering embryo development. This differentiation process was largely conserved between humans and mice. Notably, the developmental defects of SOX9-positive human endometrial epithelial cells (similar to mouse EEC) were related to thin endometrium, whereas functional defects of SEC-similar unciliated epithelial cells were related to recurrent implantation failure (RIF). Our findings provide insights into endometrial luminal epithelial cell development directed by maternal and embryonic signaling, which is crucial for endometrial receptivity.


Assuntos
Implantação do Embrião , Células Epiteliais , Gravidez , Feminino , Humanos , Animais , Camundongos , Implantação do Embrião/genética , Desenvolvimento Embrionário , Endométrio/fisiologia , Diferenciação Celular
19.
Clin Cancer Res ; 29(18): 3779-3792, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37439870

RESUMO

PURPOSE: The dynamic interplay between glioblastoma stem cells (GSC) and tumor-associated macrophages (TAM) sculpts the tumor immune microenvironment (TIME) and promotes malignant progression of glioblastoma (GBM). However, the mechanisms underlying this interaction are still incompletely understood. Here, we investigate the role of CXCL8 in the maintenance of the mesenchymal state of GSC populations and reprogramming the TIME to an immunosuppressive state. EXPERIMENTAL DESIGN: We performed an integrative multi-omics analyses of RNA sequencing, GBM mRNA expression datasets, immune signatures, and epigenetic profiling to define the specific genes expressed in the mesenchymal GSC subsets. We then used patient-derived GSCs and a xenograft murine model to investigate the mechanisms of tumor-intrinsic and extrinsic factor to maintain the mesenchymal state of GSCs and induce TAM polarization. RESULTS: We identified that CXCL8 was preferentially expressed and secreted by mesenchymal GSCs and activated PI3K/AKT and NF-κB signaling to maintain GSC proliferation, survival, and self-renewal through a cell-intrinsic mechanism. CXCL8 induced signaling through a CXCR2-JAK2/STAT3 axis in TAMs, which supported an M2-like TAM phenotype through a paracrine, cell-extrinsic pathway. Genetic- and small molecule-based inhibition of these dual complementary signaling cascades in GSCs and TAMs suppressed GBM tumor growth and prolonged survival of orthotopic xenograft-bearing mice. CONCLUSIONS: CXCL8 plays critical roles in maintaining the mesenchymal state of GSCs and M2-like TAM polarization in GBM, highlighting an interplay between cell-autonomous and cell-extrinsic mechanisms. Targeting CXCL8 and its downstream effectors may effectively improve GBM treatment.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Animais , Camundongos , Glioblastoma/patologia , Macrófagos Associados a Tumor/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/metabolismo , Proliferação de Células , Microambiente Tumoral/genética
20.
Proteomics ; 23(18): e2200330, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37271885

RESUMO

Cardiovascular diseases (CVDs) are among the most morbid and deadly types of diseases worldwide, while the existing therapeutic approaches all have their limitations. Mouse heart undergoes a very complex postnatal developmental process, including the 1-week window in which cardiomyocytes (CMs) maintain relatively high cell activity. The underlying mechanism provides an attractive direction for CVDs treatment. Herein, we collected ventricular tissues from mice of different ages from E18.5D to P8W and performed iTRAQ-based quantitative proteomics to characterize the atlas of cardiac development. A total of 3422 proteins were quantified at all selected time points, revealing critical proteomic changes related to cardiac developmental events such as the metabolic transition from glycolysis to beta-oxidation. A cluster of significantly dysregulated proteins containing proteins that have already been reported to be associated with cardiac regeneration (Erbb2, Agrin, and Hmgb) was identified. Meanwhile, the peroxisome proliferator-activated receptor (PPAR) signaling pathway (Cpt1α, Hmgcs2, Plin2, and Fabp4) was also found specifically enriched. We further revealed that bezafibrate, a pan-activator of PPAR signaling pathway markedly enhanced H9C2 cardiomyocyte activity via enhancing Cpt1α expression. This work provides new hint that activation of PPAR signaling pathway could potentially be a therapeutic strategy for the treatment of CVDs.


Assuntos
Doenças Cardiovasculares , Miócitos Cardíacos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Animais Recém-Nascidos , Proteômica , Transdução de Sinais , Doenças Cardiovasculares/metabolismo
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