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STUDY OBJECTIVES: To examine the longer-term effect of physical activity (PA) intervention on sleep quality and whether the effect was heterogeneous between daytime nappers and non-nappers. METHODS: This study was a secondary analysis of a cluster randomized controlled trial in China. Eight villages were randomized 1:1 to intervention or control group. The intervention group received an 8-week PA intervention, while the control group did not. The primary outcome of this study was the change in the Pittsburgh Sleep Quality Index (PSQI) global score at 24 months. RESULTS: The 511 participants had a mean age of 70.94 years (SD 5.73) and 55.6% were female. The intervention showed improvements in the PSQI global score at 8 weeks (adjusted mean difference -1.05; P=0.002), and the effect diminished at 24 months (-0.64; P=0.06). There were statistically significant improvements in the PSQI global score for daytime nappers, but not for non-nappers at 8 weeks (adjusted mean difference -0.98; P=0.01 vs -1.27; P=0.05), 12 months (-0.86; P=0.03 vs -0.84; P=0.21), and 24 months (-0.80; P=0.04 vs -0.14; P=0.84), although these improvements were below the minimum detectible level of the PSQI which is 1 point. CONCLUSION: The 8-week PA intervention was effective in improving sleep quality, while the effect was diminished and below the minimum detectible level of the PSQI which is 1 point after 24 months. The effect of PA intervention on sleep quality was more pronounced in daytime nappers. Additional interventions (e.g., focusing on multiple behavioral interventions such as PA and healthy diet) are needed to maintain the beneficial effect of PA on sleep quality in the general older populations. Further research is required to confirm the mechanisms of the effect of napping and develop tailored interventions.
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The Christchurch mutation (R136S) on the APOE3 (E3S/S) gene is associated with low tau pathology and slowdown of cognitive decline despite the causal PSEN1 mutation and high levels of amyloid beta pathology in the carrier1. However, the molecular effects enabling E3S/S mutation to confer protection remain unclear. Here, we replaced mouse Apoe with wild-type human E3 or E3S/S on a tauopathy background. The R136S mutation markedly mitigated tau load and protected against tau-induced synaptic loss, myelin loss, and spatial learning. Additionally, the R136S mutation reduced microglial interferon response to tau pathology both in vivo and in vitro, suppressing cGAS-STING activation. Treating tauopathy mice carrying wild-type E3 with cGAS inhibitor protected against tau-induced synaptic loss and induced similar transcriptomic alterations to those induced by the R136S mutation across brain cell types. Thus, cGAS-STING-IFN inhibition recapitulates the protective effects of R136S against tauopathy.
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Demyelination occurs in aging and associated diseases, including Alzheimer's disease. Several of these diseases exhibit sex differences in prevalence and severity. Biological sex primarily stems from sex chromosomes and gonads releasing sex hormones. To dissect mechanisms underlying sex differences in demyelination of aging brains, we constructed a transcriptomic atlas of cell type-specific responses to illustrate how sex chromosomes, gonads, and their interaction shape responses to demyelination. We found that sex-biased oligodendrocyte and microglial responses are driven by interaction of sex chromosomes and gonads prior to myelin loss. Post demyelination, sex chromosomes mainly guide microglial responses, while gonadal composition influences oligodendrocyte signaling. Significantly, ablation of the X-linked gene Toll-like receptor 7 (Tlr7), which exhibited sex-biased expression during demyelination, abolished the sex-biased responses and protected against demyelination.
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Targeted protein degradation (TPD) technologies have catalyzed a paradigm shift in therapeutic strategies and offer innovative avenues for drug design. Hydrophobic tags (HyTs) are bifunctional TPD molecules consisting of a â³lipophilic small-molecule tagsâ³ group and a small-molecule ligand for the target protein. Despite the vast potential of HyTs, they have received relatively limited attention as a promising frontier. Leveraging their lower molecular weight and reduced numbers of hydrogen bond donors/acceptors (HBDs/HBAs) in comparison with proteolysis-targeting chimeras (PROTACs), HyTs present a compelling approach for enhancing druglike properties. In this Perspective, we explore the diverse range of HyT structures and their corresponding degradation mechanisms, thereby illuminating their broad applicability in targeting a diverse array of proteins, including previously elusive targets. Moreover, we scrutinize the challenges and opportunities entailed in developing this technology as a viable and fruitful strategy for drug discovery.
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Descoberta de Drogas , Proteínas , Proteólise , Proteínas/metabolismo , Desenho de Fármacos , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismoRESUMO
Heading date (flowering time), which greatly influences regional and seasonal adaptability in rice (Oryza sativa), is regulated by many genes in different photoperiod pathways. Here, we characterized a heading date gene, Early heading date 5 (Ehd5), using a modified bulked segregant analysis method. The ehd5 mutant showed late flowering under both short-day and long-day conditions, as well as reduced yield, compared to the wild type. Ehd5, which encodes a WD40 domain-containing protein, is induced by light and follows a circadian rhythm expression pattern. Transcriptome analysis revealed that Ehd5 acts upstream of the flowering genes Early heading date 1 (Ehd1), RICE FLOWERING LOCUS T 1 (RFT1), and Heading date 3a (Hd3a). Functional analysis showed that Ehd5 directly interacts with Rice outermost cell-specific gene 4 (Roc4) and Grain number, plant height, and heading date 8 (Ghd8), which might affect the formation of Ghd7-Ghd8 complexes, resulting in increased expression of Ehd1, Hd3a, and RFT1. In a nutshell, these results demonstrate that Ehd5 functions as a positive regulator of rice flowering and provide insight into the molecular mechanisms underlying heading date.
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Flores , Oryza , Ritmo Circadiano , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Oryza/genética , Oryza/metabolismo , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Repetições WD40/genéticaRESUMO
A series of novel stilbene-based derivatives were designed and synthesized as tubulin/HDAC dual-target inhibitors. Among forty-three target compounds, compound II-19k not only exhibited considerable antiproliferative activity in the hematological cell line K562 with IC50 value of 0.003 µM, but also effectively inhibited the growth of various solid tumor cell lines with IC50 values ranging from 0.005 to 0.036 µM. The mechanism studies demonstrated that II-19k could inhibit microtubules and HDACs at the cellular level, block cell cycle arrest at G2 phase, induce cell apoptosis, and reduce solid tumor cells metastasis. What's more, the vascular disrupting effects of compound II-19k were more pronounced than the combined administration of parent compound 8 and HDAC inhibitor SAHA. The in vivo antitumor assay of II-19k also showed the superiority of dual-target inhibition of tubulin and HDAC. II-19k significantly suppressed the tumor volume and effectively reduced tumor weight by 73.12% without apparent toxicity. Overall, the promising bioactivities of II-19k make it valuable for further development as an antitumor agent.
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Antineoplásicos , Tubulina (Proteína) , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Relação Estrutura-Atividade , ApoptoseRESUMO
Currently, bioorthogonal coupling reactions have garnered considerable interest due to their high substrate selectivity and less restrictive reaction conditions. During recent decades, bioorthogonal coupling reactions have emerged as powerful tools in drug development. This review describes the current applications of bioorthogonal coupling reactions in compound library building mediated by the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction and in situ click chemistry or conjunction with other techniques; druggability optimization with 1,2,3-triazole groups; and intracellular self-assembly platforms with ring tension reactions, which are presented from the viewpoint of drug development. There is a reasonable prospect that bioorthogonal coupling reactions will accelerate the screening of lead compounds, the designing strategies of small molecules and expand the variety of designed compounds, which will be a new trend in drug development in the future.
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Cobre , Desenvolvimento de Medicamentos , Cobre/química , Reação de Cicloadição , Azidas/química , Química Click/métodos , Alcinos/química , CatáliseRESUMO
Grain yield and grain quality are major determinants in modern breeding controlled by many quantitative traits loci (QTLs) in rice (Oryza sativa). However, the mechanisms underlying grain shape and quality are poorly understood. Here, we characterize a QTL for grain size and grain quality via map-based cloning from wild rice (W1943), GS10 (Grain Size on Chromosome 10), which encodes a protein with 6 tandem armadillo repeats. The null mutant gs10 shows slender and narrow grains with altered cell size, which has a pleiotropic effect on other agronomical traits. Functional analysis reveals that GS10 interacts with TUD1 (Taihu Dwarf1) and is epistatic to OsGSK2 (glycogen synthase kinase 2) through regulating grain shape and lamina joint inclination, indicating it is negatively involved in brassinosteroid (BR) signaling. Pyramiding gs10 and the grain size gene GW5 into cultivar GLA4 substantially improved grain shape and appearance quality. Natural variation analysis revealed that gs10 from the wild rice Oryza rufipogon W1943 is a rare allele across the rice population. Collectively, these findings advance our understanding of the underlying mechanism of grain shape and provide the beneficial allele of gs10 for future rice breeding and genetic improvement.
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Brassinosteroides , Oryza , Brassinosteroides/metabolismo , Grão Comestível/genética , Oryza/genética , Fenótipo , Melhoramento Vegetal , Locos de Características Quantitativas/genéticaRESUMO
Hydrophobic tagging (HyT) is a potential therapeutic strategy for targeted protein degradation (TPD). Norbornene was discovered as an unprecedented hydrophobic tag in this study and was used to degrade the anaplastic lymphoma kinase (ALK) fusion protein by linking it to ALK inhibitors. The most promising degrader, Hyt-9, potently reduced ALK levels through Hsp70 and the ubiquitin-proteasome system (UPS) in vitro without compensatory upregulation of ALK. Furthermore, Hyt-9 exhibited a significant tumor-inhibiting effect in vivo with moderate oral bioavailability. More importantly, norbornene can also be used to degrade the intractable enhancer of zeste homolog 2 (EZH2) when tagged with the EZH2 inhibitor tazemetostat. Thus, the discovery of novel hydrophobic norbornene tags shows promise for the future development of TPD technology.
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Antineoplásicos , Neoplasias , Humanos , Proteólise , Inibidores Enzimáticos , Complexo de Endopeptidases do Proteassoma , Inibidores de Proteínas Quinases/farmacologia , Antineoplásicos/químicaRESUMO
T cell activation and function depend on Ca2+ signals mediated by store-operated Ca2+ entry (SOCE) through Ca2+ release-activated Ca2+ (CRAC) channels formed by ORAI1 proteins. We here investigated how SOCE controls T cell function in pulmonary inflammation during a T helper 1 (TH1) cell-mediated response to influenza A virus (IAV) infection and TH2 cell-mediated allergic airway inflammation. T cell-specific deletion of Orai1 did not exacerbate pulmonary inflammation and viral burdens following IAV infection but protected mice from house dust mite-induced allergic airway inflammation. ORAI1 controlled the expression of genes including p53 and E2F transcription factors that regulate the cell cycle in TH2 cells in response to allergen stimulation and the expression of transcription factors and cytokines that regulate TH2 cell function. Systemic application of a CRAC channel blocker suppressed allergic airway inflammation without compromising immunity to IAV infection, suggesting that inhibition of SOCE is a potential treatment for allergic airway disease.
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Canais de Cálcio , Vírus da Influenza A , Alérgenos , Animais , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Citocinas/metabolismo , Fatores de Transcrição E2F , Inflamação , Camundongos , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismoRESUMO
Wild rice (Oryza rufipogon) has a lower panicle seed setting rate (PSSR) and gamete fertility than domesticated rice (Oryza sativa), but the genetic mechanisms of this phenomenon remain unknown. Here, we cloned a null allele of OsMLH1, an ortholog of MutL-homolog 1 to yeast and mammals, from wild rice O. rufipogon W1943 and revealed a 5.4-kb retrotransposon insertion in OsMLH1 is responsible for the low PSSR in wild rice. In contrast to the wild-type, a near isogenic line NIL-mlh1 exhibits defective crossover (CO) formation during meiosis, resulting in reduced pollen viability, partial embryo lethality, and low PSSR. Except for the mutant of mismatch repair gene postmeiotic segregation 1 (Ospms1), all other MutL mutants from O. sativa indica subspecies displayed male and female semi-sterility similar to NIL-mlh1, but less severe than those from O. sativa japonica subspecies. MLH1 and MLH3 did not contribute in an additive fashion to fertility. Two types of MutL heterodimers, MLH1-PMS1 and MLH1-MLH3, were identified in rice, but only the latter functions in promoting meiotic CO formation. Compared to japonica varieties, indica cultivars had greater numbers of CO events per meiosis. Our results suggest that low fertility in wild rice may be caused by different gene defects, and indica and japonica subspecies have substantially different CO rates responsible for the discrepancy between the fertility of mlh1 and mlh3 mutants.
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Oryza , Proteínas de Saccharomyces cerevisiae , Animais , Oryza/genética , Retroelementos/genética , Saccharomyces cerevisiae/genética , Sementes/genética , Meiose/genética , Mamíferos/genética , Proteínas MutL/genética , Proteínas de Saccharomyces cerevisiae/genéticaRESUMO
Background: Tislelizumab combined with radiotherapy as a salvage treatment for patients with end-stage metastatic castration-resistant prostate cancer (mCRPC) is not reported. This study aimed to describe a protocol to evaluate the safety and efficacy of multisite radiotherapy combined with tislelizumab as a salvage therapy for mCRPC in patients who had at least one second-line treatment failure. Methods: The study included patients with mCRPC who had at least one lesion suitable for radiotherapy and failed androgen deprivation therapy (ADT), followed by at least one novel second-line endocrine therapy. All patients received tislelizumab monotherapy induction therapy for two cycles, then combined with multisite radiotherapy for one cycle, followed by tislelizumab maintenance therapy, until either disease progressed or the patient developed unacceptable toxicity. Radiation methods and lesions were individually selected according to the specified protocol. Primary endpoints included safety and objective response rate. Secondary endpoints included prostate-specific antigen (PSA) response rate, disease control rate, overall survival, radiographic progression-free survival (rPFS), and biochemical progression-free survival (bPFS). Furthermore, the exploratory endpoints included the identification of the predictive biomarkers and exploration of the correlation between biomarkers and the tumor response to the combined regimen. Discussion: This study included three treatment stages to evaluate the efficacy of immunotherapy and the combination of immunotherapy and radiotherapy for patients with mCRPC who have had at least second-line treatment failure. Additionally, radiation-related and immune-related early and late toxicities were determined, respectively. Furthermore, the study also aimed to identify the predictive biomarkers associated with immunotherapy for treating mCRPC. Trial Registration: https://www.chictr.org.cn/showproj.aspx?proj=126359, identifier ChiCTR2100046212.
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Ca2+ signals regulate the function of many immune cells and promote immune responses to infection, cancer, and autoantigens. Ca2+ influx in immune cells is mediated by store-operated Ca2+ entry (SOCE) that results from the opening of Ca2+ release-activated Ca2+ (CRAC) channels. The CRAC channel is formed by three plasma membrane proteins, ORAI1, ORAI2, and ORAI3. Of these, ORAI1 is the best studied and plays important roles in immune function. By contrast, the physiological role of ORAI3 in immune cells remains elusive. We show here that ORAI3 is expressed in many immune cells including macrophages, B cells, and T cells. To investigate ORAI3 function in immune cells, we generated Orai3-/- mice. The development of lymphoid and myeloid cells in the thymus and bone marrow was normal in Orai3-/- mice, as was the composition of immune cells in secondary lymphoid organs. Deletion of Orai3 did not affect SOCE in B cells and T cells but moderately enhanced SOCE in macrophages. Orai3-deficient macrophages, B cells, and T cells had normal effector functions in vitro. Immune responses in vivo, including humoral immunity (T cell dependent or independent) and antitumor immunity, were normal in Orai3-/- mice. Moreover, Orai3-/- mice showed no differences in susceptibility to septic shock, experimental autoimmune encephalomyelitis, or collagen-induced arthritis. We conclude that despite its expression in myeloid and lymphoid cells, ORAI3 appears to be dispensable or redundant for physiological and pathological immune responses mediated by these cells.
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Canais de Cálcio , Cálcio , Animais , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Imunidade , Linfócitos/metabolismo , Macrófagos/metabolismo , Camundongos , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/genética , Molécula 1 de Interação Estromal/metabolismoRESUMO
The volume-regulated anion channel (VRAC) is formed by LRRC8 proteins and is responsible for the regulatory volume decrease (RVD) after hypotonic cell swelling. Besides chloride, VRAC transports other molecules, for example, immunomodulatory cyclic dinucleotides (CDNs) including 2'3'cGAMP. Here, we identify LRRC8C as a critical component of VRAC in T cells, where its deletion abolishes VRAC currents and RVD. T cells of Lrrc8c-/- mice have increased cell cycle progression, proliferation, survival, Ca2+ influx and cytokine production-a phenotype associated with downmodulation of p53 signaling. Mechanistically, LRRC8C mediates the transport of 2'3'cGAMP in T cells, resulting in STING and p53 activation. Inhibition of STING recapitulates the phenotype of LRRC8C-deficient T cells, whereas overexpression of p53 inhibits their enhanced T cell function. Lrrc8c-/- mice have exacerbated T cell-dependent immune responses, including immunity to influenza A virus infection and experimental autoimmune encephalomyelitis. Our results identify cGAMP uptake through LRRC8C and STING-p53 signaling as a new inhibitory signaling pathway in T cells and adaptive immunity.
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Ânions/metabolismo , Fosfatos de Dinucleosídeos/metabolismo , Canais Iônicos/metabolismo , Proteínas de Membrana/metabolismo , Linfócitos T/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Cálcio/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Nucleotídeos Cíclicos/metabolismo , Transdução de Sinais/fisiologiaRESUMO
BACKGROUND: Few studies examined socio-ecological factors and leisure time physical activities (LTPA) and rarely focused on self-regulation and social capital, which might play a significant role in impacting people's physical activity behavior. This study aimed to examine the direct and indirect effects of individual level (perceived benefits, perceived barriers, and self-efficacy), interpersonal level (self-regulation), social level (social capital), and environmental level factors (perceived physical environment) on LTPA among older adults. METHODS: A cross-sectional study was conducted in 737 older adults from Sichuan, China. Structural equation modeling (SEM) analysis was used to examine the associations of individual, interpersonal, social, and environmental level factors with LTPA. RESULTS: The mean age of all participants was 71.22 (range, 60-97), and 56.1% of them were women. The SEM results showed that individual level variables (ß = 0.32, ρ < 0.001), self-regulation (ß = 0.18, ρ < 0.001) and social capital (ß = 0.14, ρ < 0.001) could all directly affect LTPA while there was no significant association of perceived physical environment with LTPA. Self-regulation served as a bridge linking social capital and LTPA. Individual level variables contributed the largest total effect (0.32) on LTPA. Self-regulation and social capital had the same total effect (0.18) on LTPA. CONCLUSIONS: Factors on three levels were all significantly associated with LTPA. Interventions that incorporate individual, interpersonal, social factors may be considered to promote LTPA in older adults. Self-regulation should receive more attention in future interventions.
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Exercício Físico , Atividades de Lazer , Idoso , China , Estudos Transversais , Feminino , Humanos , Análise de Classes LatentesRESUMO
A series of novel anaplastic lymphoma kinase (ALK) degraders were designed and synthesized based on proteolysis-targeting chimera (PROTAC) technology by linking two alectinib analogs (36 and 37) with pomalidomide through linkers of different lengths and types. The most promising degrader 17 possessed a high ALK-binding affinity and potent antiproliferative activity in the ALK-dependent cell lines and did not exhibit obvious cytotoxicity in ALK fusion-negative cells. More importantly, the efficacy of compound 17 in a Karpas 299 xenograft mouse model was further evaluated based on its ALK-sustained degradation ability in vivo. The reduction in tumor weight in the compound 17-treated group (10 mg/kg/day, I.V.) reached 75.82%, while alectinib reduced tumor weight by 63.82% at a dose of 20 mg/kg/day (P.O.). Taken together, our findings suggest that alectinib-based PROTACs associated with the degradation of ALK may have promising beneficial effects for treating ALK-driven malignancies.
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Quinase do Linfoma Anaplásico/antagonistas & inibidores , Antineoplásicos/farmacologia , Carbazóis/farmacologia , Desenvolvimento de Medicamentos , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinase do Linfoma Anaplásico/metabolismo , Animais , Antineoplásicos/química , Carbazóis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Piperidinas/química , Inibidores de Proteínas Quinases/química , Proteólise/efeitos dos fármacos , Ratos , Relação Estrutura-AtividadeRESUMO
Hybrid rice breeding for exploiting hybrid vigor, heterosis, has greatly increased grain yield. However, the heterosis-related genes associated with rice grain production remain largely unknown, partly because comprehensive mapping of heterosis-related traits is still labor-intensive and time-consuming. Here, we present a quantitative trait locus (QTL) mapping method, GradedPool-Seq, for rapidly mapping QTLs by whole-genome sequencing of graded-pool samples from F2 progeny via bulked-segregant analysis. We implement this method and map-based cloning to dissect the heterotic QTL GW3p6 from the female line. We then generate the near isogenic line NIL-FH676::GW3p6 by introgressing the GW3p6 allele from the female line Guangzhan63-4S into the male inbred line Fuhui676. The NIL-FH676::GW3p6 exhibits grain yield highly increased compared to Fuhui676. This study demonstrates that it may be possible to achieve a high level of grain production in inbred rice lines without the need to construct hybrids.
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Mapeamento Cromossômico/métodos , Grão Comestível/genética , Vigor Híbrido/genética , Oryza/genética , Melhoramento Vegetal/métodos , Cromossomos de Plantas/genética , Locos de Características Quantitativas/genéticaRESUMO
Grain size is one of the key determinants of grain yield. Although a number of genes that control grain size in rice (Oryza sativa) have been identified, the overall regulatory networks behind this process remain poorly understood. Here, we report the map-based cloning and functional characterization of the quantitative trait locus GL6, which encodes a plant-specific plant AT-rich sequence- and zinc-binding transcription factor that regulates rice grain length and spikelet number. GL6 positively controls grain length by promoting cell proliferation in young panicles and grains. The null gl6 mutant possesses short grains, whereas overexpression of GL6 results in large grains and decreased grain number per panicle. We demonstrate that GL6 participates in RNA polymerase III transcription machinery by interacting with RNA polymerase III subunit C53 and transcription factor class C1 to regulate the expression of genes involved in rice grain development. Our findings reveal a further player involved in the regulation of rice grain size that may be exploited in future rice breeding.
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Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fatores de Transcrição/metabolismo , Alelos , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Locos de Características Quantitativas/genética , RNA Polimerase III/genética , RNA Polimerase III/metabolismo , Fatores de Transcrição/genéticaRESUMO
As a widely used anti-gout drug, benzbromarone has been found to induce hepatic toxicity in patients during clinical treatment. Previous studies have reported that benzbromarone is metabolized via cytochrome P450, thus causing mitochondrial toxicity in hepatocytes. In this study, we found that benzbromarone significantly aggravated hepatic steatosis in both obese db/db mice and high fat diet (HFD)-induced obese (DIO) mouse models. However, benzbromarone had less effect on the liver of lean mice. It was found that the expression of mRNAs encoding lipid metabolism and some liver-specific genes were obviously disturbed in benzbromarone-treated DIO mice compared to the control group. The inflammatory and oxidative stress factors were also activated in the liver of benzbromarone-treated DIO mice. In accordance with the in vivo results, an in vitro experiment using human hepatoma HepG2 cells also confirmed that benzbromarone promoted intracellular lipid accumulation under high free fatty acids (FFAs) conditions by regulating the expression of lipid metabolism genes. Importantly, prolonged treatment of benzbromarone significantly increased cell apoptosis in HepG2 cells in the presence of high FFAs. In addition, in benzbromarone-treated hyperuricemic patients, serum transaminase levels were positively correlated with patients' obesity level. CONCLUSION: This study demonstrated that benzbromarone aggravated hepatic steatosis in obese individuals, which could subsequently contribute to hepatic cell injury, suggesting a novel toxicological mechanism in benzbromarone-induced hepatotoxicity.
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Benzobromarona/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Uricosúricos/farmacologia , Adulto , Idoso , Animais , Apoptose/efeitos dos fármacos , Benzobromarona/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/metabolismo , Feminino , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Hiperuricemia/sangue , Hiperuricemia/tratamento farmacológico , Fígado/citologia , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/sangue , Obesidade/complicações , Obesidade/genética , Obesidade/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transaminases/sangue , Uricosúricos/uso terapêutico , Adulto JovemRESUMO
PPARγ agonists are widely used medications in diabetes mellitus therapy. Their role in improving adipose tissue function contributes to antidiabetic effects. The extracts of Dodonaea viscosa have been reported to exert antidiabetic activity. However, the effective mediators and the underlying mechanisms were largely unknown. In this study, we investigated the action on PPARγ transactivation and adipocyte modulation of two typical flavonoid constituents from D. viscosa, 5,4'-dihydroxy-7,8-dimethoxyflavanone and aliarin. Our results showed that 5,4'-dihydroxy-7,8-dimethoxyflavanone and aliarin were potential partial PPARγ agonists. The compounds induced adipogenesis in 3T3-L1 cells, with an upregulated adiponectin mRNA level and enhanced insulin sensitivity. The favorable effects of 5,4'-dihydroxy-7,8-dimethoxyflavanone, aliarin, and other flavonoid constituents on adipocytes might contribute to the antidiabetic efficacy of D. viscosa.