RESUMO
The successful interaction between pollen and stigma is a critical process for plant sexual reproduction, involving a series of intricate molecular and physiological events. After self-compatible pollination, a significant reduction in reactive oxygen species (ROS) production has been observed in stigmas, which is essential for pollen grain rehydration and subsequent pollen tube growth. Several scavenging enzymes tightly regulate ROS homeostasis. However, the potential role of these ROS-scavenging enzymes in the pollen-stigma interaction in Brassica napus remains unclear. Here, we showed that the activity of ascorbate peroxidase (APX), an enzyme that plays a crucial role in the detoxification of hydrogen peroxide (H2O2), was modulated depending on the compatibility of pollination in B. napus. We then identified stigma-expressed APX1s and generated pentuple mutants of APX1s using CRISPR/Cas9 technology. After compatible pollination, the BnaAPX1 pentuple mutants accumulated higher levels of H2O2 in the stigma, while the overexpression of BnaA09.APX1 resulted in lower levels of H2O2. Furthermore, the knockout of BnaAPX1 delayed the compatible response-mediated pollen rehydration and germination, which was consistent with the effects of a specific APX inhibitor, ρ-Aminophenol, on compatible pollination. In contrast, the overexpression of BnaA09.APX1 accelerated pollen rehydration and germination after both compatible and incompatible pollinations. However, delaying and promoting pollen rehydration and germination did not affect the seed set after compatible and incompatible pollination in APX1 pentuple mutants and overexpression lines, respectively. Our results demonstrate the fundamental role of BnaAPX1 in pollen rehydration and germination by regulating ROS homeostasis during the pollen-stigma interaction in B. napus.
Assuntos
Ascorbato Peroxidases , Brassica napus , Proteínas de Plantas , Ascorbato Peroxidases/metabolismo , Ascorbato Peroxidases/genética , Brassica napus/genética , Brassica napus/fisiologia , Brassica napus/enzimologia , Brassica napus/metabolismo , Flores/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Germinação , Homeostase , Peróxido de Hidrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Pólen/fisiologia , Tubo Polínico/genética , Tubo Polínico/metabolismo , Polinização , Espécies Reativas de Oxigênio/metabolismoRESUMO
Persistent human papillomavirus (HPV) infection is associated with multiple malignancies. Developing therapeutic vaccines to eliminate HPV-infected and malignant cells holds significant value. In this study, we introduced a lipid nanoparticle encapsulated mRNA vaccine expressing tHA-mE7-mE6. Mutations were introduced into E6 and E7 of HPV to eliminate their tumourigenicity. A truncated influenza haemagglutinin protein (tHA), which binds to the CD209 receptor on the surface of dendritic cells (DCs), was fused with mE7-mE6 in order to allow efficient uptake of antigen by antigen presenting cells. The tHA-mE7-mE6 (mRNA) showed higher therapeutic efficacy than mE7-mE6 (mRNA) in an E6 and E7+ tumour model. The treatment resulted in complete tumour regression and prevented tumour formation. Strong CD8+ T-cell immune response was induced, contributing to preventing and curing of E6 and E7+ tumour. Antigen-specific CD8+ T were found in spleens, peripheral blood and in tumours. In addition, the tumour infiltration of DC and NK cells were increased post therapy. In conclusion, this study described a therapeutic mRNA vaccine inducing strong anti-tumour immunity in peripheral and in tumour microenvironment, holding promising potential to treat HPV-induced cancer and to prevent cancer recurrence.
Assuntos
Vacinas Anticâncer , Células Dendríticas , Proteínas Oncogênicas Virais , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Vacinas de mRNA , Animais , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/prevenção & controle , Proteínas E7 de Papillomavirus/imunologia , Vacinas Anticâncer/imunologia , Proteínas Oncogênicas Virais/imunologia , Proteínas Oncogênicas Virais/genética , Vacinas contra Papillomavirus/imunologia , Células Dendríticas/imunologia , Humanos , Camundongos , Feminino , Linfócitos T CD8-Positivos/imunologia , Camundongos Endogâmicos C57BL , Nanopartículas , Células Apresentadoras de Antígenos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Células Matadoras Naturais/imunologia , Proteínas Repressoras/imunologia , Proteínas Repressoras/genética , Neoplasias/terapia , Neoplasias/imunologia , RNA Mensageiro/genética , Linhagem Celular Tumoral , LipossomosRESUMO
Self-incompatibility plays a vital role in angiosperms, by preventing inbreeding depression and maintaining genetic diversity within populations. Following polyploidization, many angiosperm species transition from self-incompatibility to self-compatibility. Here, we investigated the S-locus in Brassicaceae and identified distinct origins for the sRNA loci, SMI and SMI2 (SCR Methylation Inducer 1 and 2), within the S-locus. The SMI loci were found to be widespread in Cruciferae, whereas the SMI2 loci were exclusive to Brassica species. Additionally, we discovered four major S-haplotypes (BnS-1, BnS-6, BnS-7, and BnS-1300) in rapeseed. Overexpression of BnSMI-1 in self-incompatible Brassica napus ('S-70S1300S6 ') resulted in a significant increase in DNA methylation in the promoter regions of BnSCR-6 and BnSCR-1300, leading to self-compatibility. Conversely, by overexpressing a point mutation of BnSmi-1 in the 'S-70S1300S6 ' line, we observed lower levels of DNA methylation in BnSCR-6 and BnSCR-1300 promoters. Furthermore, the overexpression of BnSMI2-1300 in the 'SI-326S7S6 ' line inhibited the expression of BnSCR-7 through transcriptional repression of the Smi2 sRNA from the BnS-1300 haplotype. Our study demonstrates that the self-compatibility of rapeseed is determined by S-locus sRNA-mediated silencing of SCR after polyploidization, which helps to further breed self-incompatible or self-compatible rapeseed lines, thereby facilitating the utilization of heterosis.
Assuntos
Brassica napus , Brassica , Pequeno RNA não Traduzido , Brassica napus/genética , Brassica napus/metabolismo , Melhoramento Vegetal , Brassica/genética , Regiões Promotoras Genéticas/genética , Pequeno RNA não Traduzido/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
BACKGROUND: Asthenozoospermia is a major factor contributing to male infertility. The mitochondrial sheath (MS), an important organelle in the midpiece of spermatozoa, is crucial to sperm motility. ARMC12 is a mitochondrial peripheral membrane protein. Deletion of Armc12 impairs the arrangement of MS and causes infertility in mice. However, the role of ARMC12 in human asthenozoospermia remains unknown. OBJECTIVE: To study the genetic defects in patients with asthenozoospermia. METHODS: A total of 125 patients with asthenozoospermia and 120 men with proven fertility were recruited. Whole-exome sequencing and Sanger sequencing were performed for genetic analysis. Papanicolaou staining, HE staining, immunofluorescent staining, transmission electron microscopy and field emission scanning electron microscopy were employed to observe the morphological and structural defects of the spermatozoa and testes. Armc12-knockout mice were generated using the CRISPR-Cas9 system. Intracytoplasmic sperm injection was used to treat the patients. RESULTS: Biallelic ARMC12 mutations were identified in three patients, including homozygous mutations in two siblings from a consanguineous family and compound heterozygous mutations in one sporadic patient. ARMC12 is mainly expressed in the midpiece of elongated and late spermatids in the human testis. The patients' spermatozoa displayed multiple midpiece defects, including absent MS and central pair, scattered or forked axoneme and incomplete plasma membrane. Spermatozoa from Armc12-/- mice showed parallel defects in the midpiece. Moreover, two patients were treated with intracytoplasmic sperm injection and achieved good outcomes. CONCLUSION: Our findings prove for the first time that defects in ARMC12 cause asthenozoospermia and multiple midpiece defects in humans.
Assuntos
Proteínas do Domínio Armadillo , Astenozoospermia , Infertilidade Masculina , Animais , Humanos , Masculino , Camundongos , Astenozoospermia/genética , Infertilidade Masculina/genética , Camundongos Knockout , Mutação , Sêmen , Motilidade dos Espermatozoides/genética , Espermatozoides , Testículo , Proteínas do Domínio Armadillo/genéticaRESUMO
BACKGROUND: Growing evidence has revealed the impacts of exposure to fine particulate matter (PM2.5) and dysbiosis of gut microbiota on neuropsychiatric disorders, but the causal inference remains controversial due to residual confounders in observational studies. METHODS: This study aimed to examine the causal effects of exposure to PM2.5 on 4 major neuropsychiatric disorders (number of cases = 18,381 for autism spectrum disorder [ASD], 38,691 for attention deficit hyperactivity disorder [ADHD], 67,390 for schizophrenia, and 21,982 cases for Alzheimer's disease [AD]), and the mediation pathway through gut microbiota. Two-sample Mendelian randomization (MR) analyses were performed, in which genetic instruments were identified from genome-wide association studies (GWASs). The included GWASs were available from (1) MRC Integrative Epidemiology Unit (MRC-IEU) for PM2.5, PMcoarse, PM10, and NOX; (2) the Psychiatric Genomics Consortium (PGC) for ASD, ADHD, and schizophrenia; (3) MRC-IEU for AD; and (4) MiBioGen for gut microbiota. Multivariable MR analyses were conducted to adjust for exposure to NOX, PMcoarse, and PM10. We also examined the mediation effects of gut microbiota in the associations between PM2.5 exposure levels and neuropsychiatric disorders, using two-step MR analyses. RESULTS: Each 1 standard deviation (1.06â¯ug/m3) increment in PM2.5 concentrations was associated with elevated risk of ASD (odds ratio [OR] 1.42, 95% confidence interval [CI] 1.00-2.02), ADHD (1.51, 1.15-1.98), schizophrenia (1.47, 1.15-1.87), and AD (1.57, 1.16-2.12). For all the 4 neurodevelopmental disorders, the results were robust under various sensitivity analyses, while the MR-Egger method yielded non-significant outcomes. The associations remained significant for all the 4 neuropsychiatric disorders after adjusting for PMcoarse, while non-significant after adjusting for NOX and PM10. The effects of PM2.5 exposure on ADHD and schizophrenia were partially mediated by Lachnospiraceae and Barnesiella, with the proportions ranging from 8.31% to 15.77%. CONCLUSIONS: This study suggested that exposure to PM2.5 would increase the risk of neuropsychiatric disorders, partially by influencing the profile of gut microbiota. Comprehensive regulations on air pollutants are needed to help prevent neuropsychiatric disorders.
Assuntos
Doença de Alzheimer , Transtorno do Espectro Autista , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , Transtorno do Espectro Autista/etiologia , Transtorno do Espectro Autista/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Material Particulado/efeitos adversosRESUMO
OBJECTIVE: We aimed to identify key susceptibility gene targets in multiple datasets generated from postmortem brains and blood of Parkinson's disease (PD) patients and healthy controls (HC). METHODS: We performed a multitiered analysis to integrate the gene expression data using multiple-gene chips from 244 human postmortem tissues. We identified hub node genes in the highly PD-related consensus module by constructing protein-protein interaction (PPI) networks. Next, we validated the top four interacting genes in 238 subjects (90 sporadic PD, 125 HC and 23 Parkinson's Plus Syndrome (PPS)). Utilizing multinomial logistic regression analysis (MLRA) and receiver operating characteristic (ROC), we analyzed the risk factors and diagnostic power for discriminating PD from HC and PPS. RESULTS: We identified 1333 genes that were significantly different between PD and HCs based on seven microarray datasets. The identified MEturquoise module is related to synaptic vesicle trafficking (SVT) dysfunction in PD (P < 0.05), and PPI analysis revealed that SVT genes PPP2CA, SYNJ1, NSF and PPP3CB were the top four hub node genes in MEturquoise (P < 0.001). The levels of these four genes in PD postmortem brains were lower than those in HC brains. We found lower blood levels of PPP2CA, SYNJ1 and NSF in PD compared with HC, and lower SYNJ1 in PD compared with PPS (P < 0.05). SYNJ1, negatively correlated to PD severity, displayed an excellent power to discriminating PD from HC and PPS. CONCLUSIONS: This study highlights that SVT genes, especially SYNJ1, may be promising markers in discriminating PD from HCs and PPS.
Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Proteínas do Tecido Nervoso , Doença de Parkinson , Mapas de Interação de Proteínas , Vesículas Sinápticas , Autopsia , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Vesículas Sinápticas/genética , Vesículas Sinápticas/metabolismoRESUMO
Pollen tube (PT) growth towards the micropyle is critical for successful double fertilization. However, the mechanism of micropyle-directed PT growth is still unclear in Brassica napus. In this study, two aspartate proteases, BnaAP36s and BnaAP39s, were identified in B. napus. BnaAP36s and BnaAP39s were localized to the plasma membrane. The homologues of BnaAP36 and BnaAP39 were highly expressed in flower organs, especially in the anther. Sextuple and double mutants of BnaAP36s and BnaAP39s were then generated using CRISPR/Cas9 technology. Compared to WT, the seed-set of cr-bnaap36 and cr-bnaap39 mutants was reduced by 50% and 60%, respectively. The reduction in seed-set was also found when cr-bnaap36 and cr-bnaap39 were used as the female parent in a reciprocal cross assay. Like WT, cr-bnaap36 and cr-bnaap39 pollen were able to germinate and the relative PTs were able to elongate in style. Approximately 36% and 33% of cr-bnaap36 and cr-bnaap39 PTs, respectively, failed to grow towards the micropyle, indicating that BnaAP36s and BnaAP39s are essential for micropyle-directed PT growth. Furthermore, Alexander's staining showed that 10% of cr-bnaap39 pollen grains were aborted, but not cr-bnaap36, suggesting that BnaAP39s may also affect microspore development. These results suggest that BnaAP36s and BnaAP39s play a critical role in the growth of micropyle-directed PTs in B. napus. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01377-1.
RESUMO
Existing nanoparticle-mediated drug delivery systems for glioma systemic chemotherapy remain a great challenge due to poor delivery efficiency resulting from the blood brain barrier/blood-(brain tumor) barrier (BBB/BBTB) and insufficient tumor penetration. Here, we demonstrate a distinct design by patching doxorubicin-loaded heparin-based nanoparticles (DNs) onto the surface of natural grapefruit extracellular vesicles (EVs), to fabricate biomimetic EV-DNs, achieving efficient drug delivery and thus significantly enhancing antiglioma efficacy. The patching strategy allows the unprecedented 4-fold drug loading capacity compared to traditional encapsulation for EVs. The biomimetic EV-DNs are enabled to bypass BBB/BBTB and penetrate into glioma tissues by receptor-mediated transcytosis and membrane fusion, greatly promoting cellular internalization and antiproliferation ability as well as extending circulation time. We demonstrate that a high-abundance accumulation of EV-DNs can be detected at glioma tissues, enabling the maximal brain tumor uptake of EV-DNs and great antiglioma efficacy in vivo.
Assuntos
Neoplasias Encefálicas , Citrus paradisi , Vesículas Extracelulares , Glioma , Nanopartículas , Biomimética , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Heparina , HumanosRESUMO
KEY MESSAGE: A single dominant powdery mildew resistance gene MlNFS10 was identified in wild emmer wheat and mapped within a 0.3cM genetic interval spanning a 2.1Mb physical interval on chromosome arm 4AL. Wheat powdery mildew caused by Blumeria graminis forma specialis tritici (Bgt) is a globally devastating disease. The use of powdery mildew resistance genes from wild relatives of wheat is an effective method of disease management. Our previous research has shown that disruptive ecological selection has driven the discrete adaptations of the wild emmer wheat population on the south facing slope (SFS) and north facing slope (NFS) at the microsite of "Evolution Canyon" at Mount Carmel, Israel and demonstrated that 16 accessions in the NFS population display high resistance to 11 powdery mildew isolates (collected from different wheat fields in China). Here, we constructed bi-parental population by crossing the accession NFS-10 (resistant to 22 Bgt races collected from China in seedling resistance screen) and the susceptible line SFS2-12. Genetic analysis indicated that NFS-10 carries a single dominant gene, temporarily designated MlNFS10. Ultimately, 13 markers were successfully located within the long arm of chromosome 4A, thereby delineating MlNFS10 to a 0.3 cM interval covering 2.1 Mb (729275816-731365462) in the Chinese Spring reference sequence. We identified disease resistance-associated genes based on the RNA-seq analysis of both parents. The tightly linked InDel marker XWsdau73447 and SSR marker XWsdau72928 were developed and used for marker-assisted selection when MlNFS10 was introgressed into a hexaploid wheat background. Therefore, MlNFS10 can be used for improvement of germplasm in breeding programs for powdery mildew resistant cultivars.
Assuntos
Ascomicetos/fisiologia , Mapeamento Cromossômico/métodos , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Proteínas de Plantas/genética , Triticum/genética , Cromossomos de Plantas/genética , Resistência à Doença/imunologia , Ligação Genética , Marcadores Genéticos , Doenças das Plantas/microbiologia , Triticum/imunologia , Triticum/microbiologiaRESUMO
Selenium is a trace element necessary for the growth of organisms. Moreover, selenium supplementation can improve the immunity and fertility of the body, as well as its ability to resist oxidation, tumors, heavy metals, and pathogenic microorganisms. However, owing to the duality of selenium, excessive selenium supplementation can cause certain toxic effects on the growth and development of the body and may even result in death in severe cases. At present, increasing attention is being paid to the development and utilization of selenium as a micronutrient, but its potential toxicity tends to be neglected. This study systematically reviews recent research on the toxicological effects of selenium, aiming to provide theoretical references for selenium toxicology-related research and theoretical support for the development of selenium-containing drugs, selenium-enriched dietary supplements, and selenium-enriched foods.
Assuntos
Metais Pesados , Preparações Farmacêuticas , Selênio , Oligoelementos , Suplementos Nutricionais , Micronutrientes , Selênio/toxicidadeRESUMO
BACKGROUND Post-contrast acute kidney injury (PC-AKI) is a contributor to adverse outcomes after percutaneous coronary intervention (PCI). This study aimed to investigate whether fibrinogen-to-albumin ratio (FAR), a novel inflammation-based risk index, can predict the occurrence of PC-AKI in patients undergoing elective PCI. MATERIAL AND METHODS We retrospectively enrolled 291 patients who underwent elective PCI from June 2017 to June 2019. PC-AKI was defined as an increase in serum creatinine ≥0.3 mg/dL (≥26.5 µmol/L), or ≥1.5 times baseline within 48 to 72 hours after PCI. The area under the receiver-operating characteristic curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were calculated to make comparison for PC-AKI prediction. RESULTS PC-AKI occurred in 43 patients (14.8%). FAR showed an AUC of 0.691 (95% confidence interval: 0.64-0.74; P<0.001) in predicting PC-AKI. In stepwise multivariable logistic regression, FAR was independently associated with the occurrence of PC-AKI along with hypertension, diabetes, hemoglobin, estimated glomerular filtration rate, and left ventricular ejection fraction. FAR significantly improved PC-AKI prediction over Mehran risk score in the continuous NRI and IDI, but not AUC. CONCLUSIONS FAR is independently associated with the occurrence of PC-AKI, and can significantly improve PC-AKI prediction over Mehran risk score in patients undergoing elective PCI.
Assuntos
Injúria Renal Aguda/metabolismo , Albuminas/metabolismo , Fibrinogênio/metabolismo , Intervenção Coronária Percutânea/métodos , Injúria Renal Aguda/sangue , Idoso , Meios de Contraste , Creatinina/sangue , Procedimentos Cirúrgicos Eletivos , Feminino , Taxa de Filtração Glomerular , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Volume Sistólico , Função Ventricular EsquerdaRESUMO
Self-incompatibility (SI) in plants genetically prevents self-fertilization to promote outcrossing and genetic diversity. Its hybrids in Brassica have been widely cultivated due to the propagation of SI lines by spraying a salt solution. We demonstrated that suppression of Brassica napus SI from edible salt solution treatment was ascribed to sodium chloride and independent of S haplotypes, but it did not obviously change the expression of SI-related genes. Using the isobaric tags for relative and absolute quantitation (iTRAQ) technique, we identified 885 differentially accumulated proteins (DAPs) in Brassica napus stigmas of un-pollinated (UP), pollinated with compatible pollen (PC), pollinated with incompatible pollen (PI), and pollinated with incompatible pollen after edible salt solution treatment (NA). Of the 307 DAPs in NA/UP, 134 were unique and 94 were shared only with PC/UP. In PC and NA, some salt stress protein species, such as glyoxalase I, were induced, and these protein species were likely to participate in the self-compatibility (SC) pathway. Most of the identified protein species were related to metabolic pathways, biosynthesis of secondary metabolites, ribosome, and so on. A systematic analysis implied that salt treatment-overcoming SI in B.napus was likely conferred by at least five different physiological mechanisms: (i) the use of Ca2+ as signal molecule; (ii) loosening of the cell wall to allow pollen tube penetration; (iii) synthesis of compatibility factor protein species for pollen tube growth; (iv) depolymerization of microtubule networks to facilitate pollen tube movement; and (v) inhibition of protein degradation pathways to restrain the SI response.
Assuntos
Brassica napus/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Autoincompatibilidade em Angiospermas , Estresse Fisiológico , Brassica napus/metabolismo , Proteômica , Cloreto de SódioRESUMO
Ethanol-mediated injury, combined with gut-derived lipopolysaccharide (LPS), provokes generation of proinflammatory cytokines in Kupffer cells, causing hepatic inflammation. Among the mediators of these effects, miR-217 aggravates ethanol-induced steatosis in hepatocytes. However, the role of miR-217 in ethanol-induced liver inflammation process is unknown. Here, we examined the role of miR-217 in the responses to ethanol, LPS, or a combination of ethanol and LPS in RAW 264.7 macrophages and in primary Kupffer cells. In macrophages, ethanol substantially exacerbated LPS-mediated induction of miR-217 and production of proinflammatory cytokines compared with LPS or ethanol alone. Consistently, ethanol administration to mice led to increases in miR-217 abundance and increased production of inflammatory cytokines in isolated primary Kupffer cells exposed to the combination of ethanol and LPS. miR-217 promoted combined ethanol and LPS-mediated inhibition of sirtuin 1 expression and activity in macrophages. Moreover, miR-217-mediated sirtuin 1 inhibition was accompanied by increased activities of two vital inflammatory regulators, NF-κB and the nuclear factor of activated T cells c4. Finally, adenovirus-mediated overexpression of miR-217 led to steatosis and inflammation in mice. These findings suggest that miR-217 is a pivotal regulator involved in ethanol-induced hepatic inflammation. Strategies to inhibit hepatic miR-217 could be a viable approach in attenuating alcoholic hepatitis.
Assuntos
Hepatite Alcoólica/metabolismo , Inflamação/metabolismo , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Fosfatidato Fosfatase/metabolismo , Transdução de Sinais/fisiologia , Sirtuína 1/metabolismo , Animais , Imunoprecipitação da Cromatina , Ensaio de Imunoadsorção Enzimática , Etanol/toxicidade , Fígado Gorduroso/metabolismo , Hepatite Alcoólica/genética , Immunoblotting , Inflamação/genética , Células de Kupffer/metabolismo , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , TransfecçãoRESUMO
BACKGROUND & AIMS: Sirtuin (SIRT1) is a nicotinamide adenine dinucleotide-dependent protein deacetylase that regulates hepatic lipid metabolism by modifying histones and transcription factors. Ethanol exposure disrupts SIRT1 activity and contributes to alcoholic liver disease in rodents, but the exact pathogenic mechanism is not clear. We compared mice with liver-specific deletion of Sirt1 (Sirt1LKO) mice with their LOX littermates (controls). METHODS: We induced alcoholic liver injury in male Sirt1LKO and control mice, placing them on Lieber-DeCarli ethanol-containing diets for 10 days and then administering a single dose of ethanol (5 g/kg body weight) via gavage. Liver and serum samples were collected. We also measured messenger RNA levels of SIRT1, SFRS10, and lipin-1ß and lipin-1α in liver samples from patients with alcoholic hepatitis and individuals without alcoholic hepatitis (controls). RESULTS: On the ethanol-containing diet, livers of Sirt1LKO mice accumulated larger amounts of hepatic lipid and expressed higher levels of inflammatory cytokines than control mice; serum of Sirt1LKO mice had increased levels of alanine aminotransferase and aspartate aminotransferase. Hepatic deletion of SIRT1 exacerbated ethanol-mediated defects in lipid metabolism, mainly by altering the function of lipin-1, a transcriptional regulator of lipid metabolism. In cultured mouse AML-12 hepatocytes, transgenic expression of SIRT1 prevented fat accumulation in response to ethanol exposure, largely by reversing the aberrations in lipin-1 signaling induced by ethanol. Liver samples from patients with alcoholic hepatitis had reduced levels of SIRT1 and a higher ratio of Lpin1ß/α messenger RNAs than controls. CONCLUSIONS: In mice, hepatic deletion of Sirt1 promotes steatosis, inflammation, and fibrosis in response to ethanol challenge. Ethanol-mediated impairment of hepatic SIRT1 signaling via lipin-1 contributes to development of alcoholic steatosis and inflammation. Reagents designed to increase SIRT1 regulation of lipin-1 can be developed to treat patients with alcoholic fatty liver disease.
Assuntos
Fígado Gorduroso Alcoólico/metabolismo , Hepatócitos/metabolismo , Proteínas Nucleares/metabolismo , Fosfatidato Fosfatase/metabolismo , Transdução de Sinais/fisiologia , Sirtuína 1/deficiência , Animais , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/fisiologia , Etanol/efeitos adversos , Fígado Gorduroso Alcoólico/etiologia , Fígado Gorduroso Alcoólico/fisiopatologia , Humanos , Metabolismo dos Lipídeos/fisiologia , Fígado/enzimologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Estresse Oxidativo/fisiologia , Proteínas de Ligação a RNA/metabolismo , Fatores de Processamento de Serina-Arginina , Sirtuína 1/genética , Sirtuína 1/metabolismoRESUMO
OBJECTIVE: To determine the effect of chronic intermittent hypoxia on cognitive function and prefrontal cortex neurons in rats. METHODS: 48 adult male Wistar rats were randomly divided into two groups: control group and 50 mL/L intermittent hypoxia group (50 mL/L CIH). Rats in the CIH group were placed in the low oxygen tank, simulating intermittent hypoxia environment. At 7 d, 14 d, 21 d, and 28 d, the learning and memory ability of the rats was assessed with the Morris water maze (MWM) test; the expressions of cysteinyl aspartate specific protease (caspase)-8 protein in their prefrontal cortex were determined using Western blot method; the apoptosis of neurons was detected by the TdT mediated UTP nick end labeling (TUNEL) method. RESULTS: Compared with the controls, the CIH rats had significantly prolonged escape latency at 14 d, 21 d, and 28 d (P<0. 05) and decreased target quadrant time (P<0. 05). The prolonged escape latency increased and target quadrant time shortened with length of exposure to hypoxia (P<0. 05). Compared with controls, the CIH rats had gradually increased caspase-8 in their frontal cortex neurons, peaked at 28 d (P<0. 05). The CIH rats showed obvious structural damage and reduced neuron density in their frontal cortex neurons. They had higher levels of nerve cell apoptosis (P<0. 05), with apoptosis index increasing with length of exposure to hypoxia (P<0. 05). CONCLUSION: Severe chronic intermittent hypoxia can lead to pathological changes of frontal,cortex of rats, possibly
Assuntos
Cognição , Hipóxia , Neurônios/citologia , Córtex Pré-Frontal/patologia , Animais , Apoptose , Masculino , Memória , Córtex Pré-Frontal/citologia , Ratos , Ratos WistarRESUMO
UNLABELLED: Lipin-1 regulates lipid metabolism by way of its function as an enzyme in the triglyceride synthesis pathway and as a transcriptional coregulatory protein and is highly up-regulated in alcoholic fatty liver disease. In the present study, using a liver-specific lipin-1-deficient (lipin-1LKO) mouse model, we aimed to investigate the functional role of lipin-1 in the development of alcoholic steatohepatitis and explore the underlying mechanisms. Alcoholic liver injury was achieved by pair feeding wild-type and lipin-1LKO mice with modified Lieber-DeCarli ethanol-containing low-fat diets for 4 weeks. Surprisingly, chronically ethanol-fed lipin-1LKO mice showed markedly greater hepatic triglyceride and cholesterol accumulation, and augmented elevation of serum liver enzymes accompanied by increased hepatic proinflammatory cytokine expression. Our studies further revealed that hepatic removal of lipin-1 in mice augmented ethanol-induced impairment of hepatic fatty acid oxidation and lipoprotein production, likely by way of deactivation of peroxisome proliferator-activated receptor γ coactivator-1 alpha, a prominent transcriptional regulator of lipid metabolism. CONCLUSIONS: Liver-specific lipin-1 deficiency in mice exacerbates the development and progression of experimental alcohol-induced steatohepatitis. Pharmacological or nutritional modulation of hepatic lipin-1 may be beneficial for the prevention or treatment of human alcoholic fatty liver disease.
Assuntos
Fígado Gorduroso Alcoólico/etiologia , Proteínas Nucleares/deficiência , Fosfatidato Fosfatase/deficiência , Animais , Dieta com Restrição de Gorduras , Fígado Gorduroso Alcoólico/metabolismo , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fosfatidato Fosfatase/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismoRESUMO
A highly efficient, regioselective method for the direct 2,3-O-isopropylidenation of α-D-mannopyranosides is reported. Treatment of various α-D-mannopyranosides with 0.12 equiv of the TsOH·H2O and 2-methoxypropene at 70 °C gave 2,3-O-isopropylidene-α-D-mannopyranosides directly in 80%~90% yields. Based on this method, a 3,6-branched α-D-mannosyl trisaccharide was prepared in 50.4% total yield using p-nitrophenyl 2,3-O-isopropylidene-α-D-mannopyranoside as the starting material.
Assuntos
Manose/química , Trissacarídeos/síntese química , Sequência de Carboidratos , Técnicas de Química Sintética , Éteres Metílicos/química , Estrutura Molecular , Trissacarídeos/química , Compostos de Vinila/químicaRESUMO
A series of novel glycosylthiadiazole derivatives, namely 2-phenylamino-5-glycosyl-1,3,4-thiadiazoles, were designed and synthesized by condensation between sugar aldehydes A/B and substituted thiosemicarbazide C followed by oxidative cyclization by treating with manganese dioxide. The original fungicidal activities results showed that some title compounds exhibited excellent fungicidal activities against Sclerotinia sclerotiorum (Lib.) de Bary and Pyricularia oryzae Cav, especially compounds F-5 and G-8 which displayed better fungicidal activities than the commercial fungicide chlorothalonil. At the same time, the preliminary studies based on the Elson-Morgan method indicated that many compounds exhibited some inhibitory activity toward glucosamine-6-phosphate synthase (GlmS). The structure-activity relationships (SAR) are discussed in terms of the effects of the substituents on both the benzene and the sugar ring.
Assuntos
Antifúngicos/farmacologia , Fungos/efeitos dos fármacos , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/antagonistas & inibidores , Tiadiazóis/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/enzimologia , Helminthosporium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Estrutura Molecular , Nitrilas/farmacologia , Phytophthora/efeitos dos fármacos , Rhizoctonia/efeitos dos fármacos , Relação Estrutura-Atividade , Tiadiazóis/síntese química , Tiadiazóis/química , Verticillium/efeitos dos fármacosRESUMO
Self-incompatibility (SI) is an important genetic mechanism exploited by numerous angiosperm species to prevent inbreeding. This mechanism has been widely used in the breeding of SI trilinear hybrids of Brassica napus. The SI responses in these hybrids can be overcome by using a salt (NaCl) solution, which is used for seed propagation in SI lines. However, the mechanism underlying the NaCl-induced breakdown of the SI response in B. napus remains unclear. Here, we investigated the role of two key proteins, BnaPLDα1 and BnaMPK6, in the breakdown of SI induced by NaCl. Pollen grain germination and seed set were reduced in BnaPLDα1 triple mutants following incompatible pollination with NaCl treatment. Conversely, SI responses were partially abolished by overexpression of BnaC05.PLDα1 without salt treatment. Furthermore, we observed that phosphatidic acid (PA) produced by BnaPLDα1 bound to B. napus BnaMPK6. The suppression and enhancement of the NaCl-induced breakdown of the SI response in B. napus were observed in BnaMPK6 quadruple mutants and BnaA05.MPK6 overexpression lines, respectively. Moreover, salt-induced stigmatic reactive oxygen species (ROS) accumulation had a minimal effect on the NaCl-induced breakdown of the SI response. In conclusion, our results demonstrate the essential role of the BnaPLDα1-PA-BnaMPK6 pathway in overcoming the SI response to salt treatment in SI B. napus. Additionally, our study provides new insights into the relationship between SI signaling and salt stress response. SIGNIFICANCE STATEMENT: A new molecular mechanism underlying the breakdown of the NaCl-induced self-incompatibility (SI) response in B. napus has been discovered. It involves the induction of BnaPLDα1 expression by NaCl, followed by the activation of BnaMPK6 through the production of phosphatidic acid (PA) by BnaPLDα1. Ultimately, this pathway leads to the breakdown of SI. The involvement of the BnaPLDα1-PA-BnaMPK6 pathway in overcoming the SI response following NaCl treatment provides new insights into the relationship between SI signalling and the response to salt stress.
Assuntos
Brassica napus , Proteínas de Plantas , Cloreto de Sódio , Brassica napus/genética , Brassica napus/fisiologia , Brassica napus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cloreto de Sódio/farmacologia , Autoincompatibilidade em Angiospermas/genética , Regulação da Expressão Gênica de Plantas , PolinizaçãoRESUMO
Soot nanoparticles (SNPs) are black carbon prevalent in atmospheric environment with significant impacts on public health, leading to neurodegenerative diseases including development of Parkinson's disease (PD). This study investigated the effects of SNPs exposure on PD symptoms, employing both in vivo and in vitro PD models. In the in vivo experiments, animal behavior assessments showed that SNPs exposure exacerbated motor and cognitive impairments in PD mice. Molecular biology techniques further unveiled that SNPs aggravated degeneration of dopaminergic neurons. In vitro experiments revealed that SNPs exposure intensified ferroptosis of PD cells by increasing reactive oxygen species and iron ion levels, while reducing glutathione levels and mitochondrial membrane potential. Sequencing tests indicated elevated N6-methyladenosine (m6A) alteration of the ferroptosis-related protein, acyl-CoA synthetase long chain family member 4 (ACSL4). This study demonstrates that SNPs may exacerbate the onset and progression of PD by recruiting YTH domain-containing family protein 1 (YTHDF1) protein, enhancing m6A methylation in the ACSL4 5'UTR, amplifying ACSL4 protein expression, and accelerating the ferroptosis process in dopaminergic neurons. These molecular mechanisms underlying SNPs exacerbation of PD development may provide crucial insights for formulating environmental safety regulations and potential therapeutic strategies addressing PD in populations residing in regions with varied air quality.