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Malnutrition is an important risk factor for multiple organ dysfunction syndrome in the elderly (MODSE) and seriously affects the occurrence, progression and prognosis of MODSE. Shenling Baizhu Power (SBP), a classic formula from traditional Chinese medicine (TCM), when integrated with enteral nutrition, has been proven to be an effective clinical strategy for treating the patients of MODSE with malnutrition. This study aimed to investigate the metabolic changes during disease occurrence and SBP treatment, and to discover potential metabolic biomarkers for the diagnosis and efficacy evaluation. An untargeted metabolomics strategy based on UHPLC-Q-Orbitrap-HRMS was performed to reveal the differential serum metabolites between MODSE patients with malnutrition (n=59) and healthy controls (n=33), and those between patients treated with enteral nutrition (n=31) and SBP combined with enteral nutrition (n=28). Significantly different metabolites were identified and mapped onto the network of metabolic pathways to explore the metabolic disorders caused by the disease and the metabolic regulatory mechanism of SBP. Additionally, the area under the curve (AUC) of the potential biomarkers was investigated for predicting the disease and the efficacy of SBP. Sixty differential metabolites were identified between the disease and control groups, which were mainly related to amino acid metabolism, energy metabolism and carbohydrate metabolism. In the same way, 50 differential metabolites associated with SBP treatment were identified, which improved metabolic abnormalities in vivo mainly by regulating the above-mentioned metabolic pathways. Finally, 13 differential metabolites in common were selected as the potential biomarkers and the AUC value of each biomarker was within the range of 0.8-1.0, indicating that these biomarkers had high prediction accuracy for the diagnosis and efficacy evaluation of MODSE with malnutrition. This study demonstrates that serum metabolomics approaches based on the UHPLC-Q-Orbitrap-HRMS platform can be applied as a tool to reveal the metabolic changes induced by MODSE with malnutrition and SBP can play an important role in the clinical application.
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SIRT6 is a key member of the mammalian sirtuin family of conserved nicotinamide adenine dinucleotide (NAD+ )-dependent deacetylases. Previous studies have shown that SIRT6 can regulate metabolism, DNA damage repair and aging. Ovarian aging process usually share similar mechanisms with general aging, which is characterized by decreases in both numbers of ovarian follicles and the quality of oocytes. It is reported that the expression level of SIRT6 was significantly decreased in the ovaries of aged mice, and the level of SIRT6 was positively correlated with ovarian reserve, indicating that SIRT6 may be potential markers of ovarian aging. However, its biological roles in follicular development are still unclear. Here, we explored the effect of SIRT6 on follicular development and found that ovarian development was interrupted in SIRT6 knockout (KO) mice, leading to disruptions of puberty and the estrus cycle, significant decreases in numbers of secondary and antral follicles, and decreased collagen in the ovarian stroma. Plod1, a lysyl hydroxylase that is vital for collagen crosslinking and deposition, was decreased at both the mRNA and protein levels in SIRT6-deficient ovaries and granulosa cells (GCs). Additionally, we found abnormal estrogen levels in both SIRT6 KO mice and SIRT6 KD GCs, accompanied by decreases in the levels of the estrogen biosynthesis genes Cyp11a1, Cyp19a1, Mgarp, and increases in the levels of TNF-α and NF-κB. These results confirmed the effect of SIRT6 on follicular development and revealed a possible molecular mechanism for SIRT6 involvement in follicular development via effects on estrogen biosynthesis and collagen formation.
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Ovário , Sirtuínas , Animais , Feminino , Camundongos , Estrogênios/metabolismo , Mamíferos/metabolismo , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo , Sirtuínas/genética , Sirtuínas/metabolismo , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismoRESUMO
We explored the networks and discriminant abilities of the current Psychosomatic Symptoms Scale (PSSS) in pharmacists for future abbreviation. Ten thousand seven hundred twenty-one pharmacists participated in this study through an online investigation. We used network analysis to reveal the central and bridge symptoms between the subscales (psychological and somatic symptoms) of the PSSS. Then, we utilized item response theory (IRT) to identify discriminant abilities of the current 26-item of PSSS. Over twenty percent of the pharmacists were troubled with significant psychosomatic issues during the pandemic. Risk factors included age, lack of support, and impaired general health conditions. The network analysis revealed that "Irritability" was central to the psychological subscale and "Fatigue" was central to the somatic subscale. "Irritability-Fatigue," "Fatigue-Obsession," and "Self-injury idea-Perineum discomfort" was bridging between the somatic and psychological subscales. IRT found that "Anhedonia," "Depression," "Tightness," "Palpitations," and "Difficulty breathing" were highly discriminated. A future version of PSSS could be abbreviated according to the highlighted items, and they should also be emphasized in future psychosomatic research and targets for intervention. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Pandemias , Farmacêuticos , Humanos , Anedonia , Bases de Dados Factuais , Fadiga/diagnóstico , Fadiga/epidemiologiaRESUMO
The charge process of lithium-sulfur batteries (LSBs) is a process in which molecular polarity decreases and the volume shrinks gradually, which is the process most likely to cause lithium polysulfides (LiPSs) loss and interfacial collapse. In this work, GeS2 is utilized, whose (111) lattice plane exactly matches with the (113) lattice of α-S8 , to solve these problems. GeS2 can regulate the interconversion-deposition behavior of S-species during the charge process. Soluble LiPSs can be spontaneously adsorbed on the GeS2 surface, then obtain electrons and eventually convert to α-S8 molecules. More importantly, the α-S8 molecules will crystallize uniformly along the (111) lattice plane of GeS2 to maintain a stable cathode-electrolyte interface. Therefore, outstanding charge/discharge LSBs are successfully accomplished.
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Early embryonic development arrest (EEDA) is a unique form of early spontaneous abortion in pregnant women, which is previously suggested to be associated with metabolic abnormalities. Noninvasive biomarkers would significantly improve its diagnosis and clinical outcome. Here, we performed a targeted metabolomics study in plasma from EEDA patients (n = 27) and normal pregnant women (NPW, n = 27) using liquid chromatography coupled with mass spectrometry (LC-MS) to identify potential diagnostic marker metabolites. Our results showed significantly different plasma metabolic profiles between EEDA patients and NPW. Particularly, EEDA patients showed significant alterations in amino acid, carbohydrate, and vitamin metabolism, which were characterized by 21 significantly increased metabolites and five decreased metabolites in plasma. Further receiver operating characteristic analysis showed that an optimal combination of S-methyl-5'-thioadenosine, kynurenine, leucine, and malate could be used as a panel of metabolites for EEDA diagnosis. The area under the curve of the metabolite panel was 0.941, suggesting a better performance than any single metabolite for the diagnosis of EEDA. In summary, our study identifies a panel of differential metabolites in plasma that could act as potential biomarkers for the diagnosis of EEDA in clinical settings.
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Metaboloma , Metabolômica , Humanos , Feminino , Gravidez , Metabolômica/métodos , Cromatografia Líquida , Biomarcadores , Desenvolvimento EmbrionárioRESUMO
A cholic acid-conjugated oxaliplatin, LLC-202, is developed as a novel prodrug for liver cancer. The conjugate is obtained by using 3-NH2-cyclobutane-1,1-dicarboxylate as a linker between the oxaliplatin analogue and cholic acid moiety and cholic acid is strongly bonded to the linker via an amide bond. Pharmacokinetic experiment shows that LLC-202 is mainly distributed and accumulated in the liver after intravenous administration to Sprague-Dawley rats, revealing the liver-targeting profile. Compared to oxaliplatin, LLC-202 is more easily taken up by human liver cancer cells than normal human liver cells. LLC-202 exhibits higher in vitro anticancer activity and higher efficacy comparable to oxaliplatin in treating primary hepatocellular carcinoma in C57BL/6 mice. It can significantly prolong the survival time of tumor-bearing mice by inducing apoptosis and inhibiting proliferation of cancer cells. In addition, LLC-202 shows less cytotoxicity toward normal human liver cells than oxaliplatin. Its acute toxicity in healthy Kunming (KM) mice after i.v. administration is comparable to oxaliplatin. Histopathological examination reveals that the main toxicity of LLC-202 in mice is the depression of bone marrow hematopoietic cells. The results suggest that LLC-202 has great potential for further development as a new prodrug specific for liver cancer.
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Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Pró-Fármacos , Camundongos , Ratos , Humanos , Animais , Oxaliplatina/farmacologia , Pró-Fármacos/farmacologia , Ácido Cólico/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Ratos Sprague-Dawley , Camundongos Endogâmicos C57BL , Neoplasias Hepáticas/tratamento farmacológico , Antineoplásicos/químicaRESUMO
Sirtuin 6 (SIRT6) is a nuclear silencing information regulator that is widely expressed in brain. Inhibition of SIRT6 in the brain induced antidepressant effects in rodents. However, SIRT6 knockout in neurons induced developmental retardation and cognitive impairments. In this study, a mouse strain of astrocyte conditional knockout SIRT6 (AKO) was constructed. Unlike whole brain SIRT6 knockout mice, AKO mice did not show growth retardation. We showed that SIRT6 knockout in astrocytes did not impair the learning and memory ability of mice. Chronic unpredictable mild stress (CUMS) was used to evaluate the anti-depression and anti-anxiety effects in mice. In tail suspension test and forced swimming test, AKO mice did not show depression like phenotype induced by CUMS. In addition, knockout of SIRT6 in astrocytes alleviated the high anxiety level induced by CUMS in light and dark box test, open field test and elevated cross maze test. Three box social test showed that the deletion of SIRT6 in astrocytes changed the social preference of mice. Re-expression of SIRT6 in astrocytes mediated by adeno-associated virus reversed the social preference of AKO mice, but the re-expression also eliminated the anti-depression and anti-anxiety effects in AKO mice. Deletion of SIRT6 in astrocytes change the purine metabolic homeostasis of medial prefrontal cortex in mice. The results of transcriptomics and metabolomics analysis showed that the deletion of SIRT6 would change the purine metabolic pathway of cultured astrocytes and increase the contents of inosine and the second messenger cyclic adenosine monophosphate in astrocytes. In conclusion, knockout of SIRT6 in astrocytes induced anti-depression and anti-anxiety effects in mice without impairing the development and cognitive ability of mice.
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Ansiolíticos , Sirtuínas , Animais , Camundongos , Ansiolíticos/farmacologia , Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Astrócitos/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Sirtuínas/antagonistas & inibidores , Sirtuínas/genética , Sirtuínas/metabolismo , Estresse Psicológico/metabolismoRESUMO
Aging-associated microbial dysbiosis exacerbates various disorders and dysfunctions, and is a major contributor to morbidity and mortality in the elderly, but the underlying cause of this aging-related syndrome is confusing. SIRT6 knockout (SIRT6 KO) mice undergo premature aging and succumb to death by 4 weeks, and are therefore useful as a premature aging research model. Here, fecal microbiota transplantation from SIRT6 KO mice into wild-type (WT) mice phenocopies the gut dysbiosis and premature aging observed in SIRT6 KO mice. Conversely, an expanded lifespan was observed in SIRT6 KO mice when transplanted with microbiota from WT mice. Antibiotic cocktail treatment attenuated inflammation and cell senescence in KO mice, directly suggesting that gut dysbiosis contributes to the premature aging of SIRT6 KO mice. Increased Enterobacteriaceae translocation, driven by the overgrowth of Escherichia coli, is the likely mechanism for the premature aging effects of microbiome dysregulation, which could be reversed by a high-fat diet. Our results provide a mechanism for the causal link between gut dysbiosis and aging, and support a beneficial effect of a high-fat diet for correcting gut dysbiosis and alleviating premature aging. This study provides a rationale for the integration of microbiome-based high-fat diets into therapeutic interventions against aging-associated diseases.
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Senilidade Prematura , Microbioma Gastrointestinal , Sirtuínas , Animais , Camundongos , Senilidade Prematura/genética , Dieta Hiperlipídica , Disbiose/etiologia , Enterobacteriaceae , Camundongos Endogâmicos C57BLRESUMO
Overexpression is one of the classical approaches to study pleiotropic functions of genes of interest. To achieve overexpression, we often increase the transcription by introducing genes on exogenous vectors or by using the CRISPR/dCas9-based transcriptional activation system. To date, the most efficient CRISPR/dCas9-based transcriptional activator is the Synergistic Activation Mediator (SAM) system whereby three different transcriptional activation domains are directly fused to dCas9 and MS2 phage Coat Protein (MCP), respectively, and the system in Drosophila is named flySAM. Here we describe the effective and convenient transcriptional activation system, flySAM, starting from vector construction, microinjection, and transgenic fly selection to the phenotypic analysis.
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Sistemas CRISPR-Cas , Drosophila , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas/genética , Drosophila/genética , Drosophila/metabolismo , Fatores de Transcrição/metabolismo , Ativação TranscricionalRESUMO
The promotional effects of inert nitrides for metal catalysts in the electrolysis are rarely reported. Recently, we reported an efficient Ni-VN/NF (that NF represents Ni foam) composite by nitriding treatment of NiV-layered double hydroxides (NiV-LDH) precursor that was in-situ hydrothermal growth on nickel foam. The optimal Ni-VN/NF exhibited outstanding electrocatalytic performance for hydrogen evolution reaction (HER) with a small overpotential of 39 mV at 10 mA cm-2 and strong durability for 100 h without degradation. The optimized electronic structure and local charge density at the hetero-interface of Ni-VN, evidenced by both experiment and DFT results, were significantly modulated by the electron transfer from Ni to V-N bond at the interfaces, leading to moderate H* adsorption energy and diminished barrier for H2O dissociation, synergistically promoted basic HER. This work highlights the design principle of strong metal-nitride interactions for advanced HER catalysts.
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Although primary vesical calculi is an ancient disease, the mechanism of calculi formation remains unclear. In this study, we established a novel primary vesical calculi model with d,l-choline tartrate in mice. Compared with commonly used melamine and ethylene glycol models, our model was the only approach that induced vesical calculi without causing kidney injury. Previous studies suggest that proteins in the daily diet are the main contributors to the prevention of vesical calculi, yet the effect of fat is overlooked. To assay the relationship of dietary fat with the formation of primary vesical calculi, d,l-choline tartrate-treated mice were fed a high-fat, low-fat, or normal-fat diet. Genetic changes in the mouse bladder were detected with transcriptome analysis. A high-fat diet remarkably reduced the morbidity of primary vesical calculi. Higher fatty acid levels in serum and urine were observed in the high-fat diet group, and more intact epithelia in bladder were observed in the same group compared with the normal- and low-fat diet groups, suggesting the protective effect of fatty acids on bladder epithelia to maintain its normal histological structure. Transcriptome analysis revealed that the macrophage differentiation-related gene C-X-C motif chemokine ligand 14 (Cxcl14) was upregulated in the bladders of high-fat diet-fed mice compared with those of normal- or low-fat diet-fed mice, which was consistent with histological observations. The expression of CXCL14 significantly increased in the bladder in the high-fat diet group. CXCL14 enhanced the recruitment of macrophages to the crystal nucleus and induced the transformation of M2 macrophages, which led to phagocytosis of budding crystals and prevented accumulation of calculi. In human bladder epithelia (HCV-29) cells, high fatty acid supplementation significantly increased the expression of CXCL14. Dietary fat is essential for the maintenance of physiological functions of the bladder and for the prevention of primary vesical calculi, which provides new ideas for the reduction of morbidity of primary vesical calculi.
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Although calorie restriction has been reported to extend lifespan in several organisms, animals subjected to calorie restriction consume not only fewer calories but also smaller quantities of food. Whether it is the overall restriction of calories or the coincidental reduction in the quantity of food consumed that mediates the anti-aging effects is unclear. Here, we subjected mice to five dietary interventions. We showed that both calorie and quantity restriction could improve early survival, but no maximum lifespan extension was observed in the mice fed isocaloric diet in which food quantity was reduced. Mice fed isoquant diet with fewer calories showed maximum lifespan extension and improved health among all the groups, suggesting that calorie intake rather than food quantity consumed is the key factor for the anti-aging effect of calorie restriction. Midlife liver gene expression correlations with lifespan revealed that calorie restriction raised fatty acid biosynthesis and metabolism and biosynthesis of amino acids but inhibited carbon metabolism, indicating different effects on fatty acid metabolism and carbohydrate metabolism. Our data illustrate the effects of calories and food quantity on the lifespan extension by calorie restriction and their potential mechanisms, which will provide guidance on the application of calorie restriction to humans.
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Envelhecimento/metabolismo , Restrição Calórica , Ingestão de Energia , Ácidos Graxos/metabolismo , Expectativa de Vida , Longevidade , Aminoácidos/metabolismo , Animais , Carbono/metabolismo , Dieta , Ácidos Graxos/biossíntese , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BLRESUMO
Notch signaling and epigenetic factors are known to play critical roles in regulating tissue homeostasis in most multicellular organisms, but how Notch signaling coordinates with epigenetic modulators to control differentiation remains poorly understood. Here, we identify heterochromatin protein 1c (HP1c) as an essential epigenetic regulator of gut homeostasis in Drosophila. Specifically, we observe that HP1c loss-of-function phenotypes resemble those observed after Notch signaling perturbation and that HP1c interacts genetically with components of the Notch pathway. HP1c represses the transcription of Notch target genes by directly interacting with Suppressor of Hairless (Su(H)), the key transcription factor of Notch signaling. Moreover, phenotypes caused by depletion of HP1c in Drosophila can be rescued by expressing human HP1γ, suggesting that HP1γ functions similar to HP1c in Drosophila. Taken together, our findings reveal an essential role of HP1c in normal development and gut homeostasis by suppressing Notch signaling.
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Proteínas de Drosophila , Animais , Proteínas Cromossômicas não Histona/genética , Drosophila/genética , Proteínas de Drosophila/genética , Heterocromatina , Homeostase , Humanos , Receptores Notch/genéticaRESUMO
METHODS: Relevant potential targets for EC were obtained based on Traditional Chinese Medicine System Pharmacology Database (TCMSP), a bioinformatics analysis tool for molecular mechanism of Traditional Chinese Medicine (BATMAN-TCM) and STITCH databases. The Online Mendelian Inheritance in Man (OMIM) and GeneCards databases were utilized to screen the known POI-related targets, while Cytoscape software was used for network construction and visualization. Then, the Gene Ontology (GO) and pathway enrichment analysis were carried out by the Database for Annotation, Visualization and Integrated Discovery (DAVID) database. Furthermore, KGN cells were performed to validate the predicted results in oxidative stress (OS) model, and antioxidant effect was examined. RESULTS: A total of 70 potential common targets for EC in the treatment of POI were obtained through network pharmacology. Metabolic process, response to stimulus and antioxidant activity occupied a leading position of Gene Ontology (GO) enrichment. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that PI3K/protein kinase B (AKT), TNF, estrogen, VEGF and MAPK signaling pathways were significantly enriched. In addition, cell experiments showed that EC exhibited antioxidant effects in an H2O2-mediated OS model in ovarian granulosa cells by regulating the expression of PI3K/AKT/nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway and multiple downstream antioxidant enzymes. CONCLUSION: EC could regulate multiple signaling pathways and several biological processes (BPs). EC had the ability to down-regulate elevated OS level through the PI3K/AKT/Nrf2 signaling pathway and represented a potential novel treatment for POI.
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Catequina/farmacologia , Insuficiência Ovariana Primária/patologia , Antioxidantes/farmacologia , Catequina/química , Bases de Dados Genéticas , Feminino , Ontologia Genética , Humanos , EstereoisomerismoRESUMO
Spermatogenesis-associated protein 4 (SPATA4) is conserved across multiple species. However, the function of this gene remains largely unknown. In this study, we generated Spata4 transgenic mice to explore tissue-specific function of SPATA4. Spata4 overexpression mice displayed increased subcutaneous fat tissue compared with wild-type littermates at an old age, while this difference was not observed in younger mice. Aging-induced ectopic fat distribution, inflammation, and insulin resistance were also significantly attenuated by SPATA4. In vitro, SPATA4 promoted preadipocyte differentiation through activation of the ERK1/2 and C/EBPß pathway and increased the expression of adipokines. These data suggest SPATA4 can regulate lipid accumulation in a tissue-specific manner and improve aging-induced dysmetabolic syndromes. Clarifying the mechanism of SPATA4 functioning in lipid metabolism might provide novel therapeutic targets for disease interventions.
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Tecido Adiposo/metabolismo , Proteínas/metabolismo , Envelhecimento , Animais , Diferenciação Celular , Humanos , Camundongos , Camundongos TransgênicosRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Jiajian Guishen Formula (JJGSF), which is a prescription of Traditional Chinese Medicine (TCM), has been reported to be useful in the treatment of premature ovarian insufficiency (POI). AIM OF THE STUDY: To investigate the therapeutic effects of JJGSF on the treatment of POI induced by 4-vinylcyclohexene diep-oxide (VCD), an endocrine-disrupting chemical (EDC), and to elucidate the potential mechanism. MATERIALS AND METHODS: Female 8-week-old ICR mice (N = 72) were randomized into six groups, containing the Model group, Control group, three JJGSF groups, and Progynova group which was served as a positive control. After model establishment by VCD, the Progynova group were given a daily intragastric administration of Progynova, and the three JJGSF groups (high dose group, medium dose group and low dose group) received a daily intragastric administration of JJGSF at doses of 9, 4.5 and 2.25 g/kg for four weeks. The general growth of the mice was observed and the estrous cycles were examined. The serum hormone concentrations were measured by enzyme-linked immunosorbent assay (ELISA). To explore the potential mechanism of effect, the protein expressions of H3K9me3, HP1, and HMGA1/HMGA2 related to senescence-associated heterochromatic foci (SAHF), were determined by Immunofluorescence and Western blot analysis, respectively. RESULTS: After treating with JJGSF, the estrous cycles were improved significantly. The level of estrogen (E2) and anti-müllerian hormone (AMH) was increased and the ratio of follicle-stimulating hormone (FSH) to luteinizing hormone (LH) in serum was decreased significantly. Furthermore, a significant down-regulation of HMGA1/HMGA2 on protein level, a reduction distribution of HP1 and H3K9me3 in ovarian, and a lower fraction of SAHF-positive cells were observed after the administration with JJGSF, additionally effects showed a positive correlation with dosages. CONCLUSIONS: JJGSF could treat POI by the mechanism of inhibiting SAHF.
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Medicamentos de Ervas Chinesas/farmacologia , Heterocromatina/efeitos dos fármacos , Insuficiência Ovariana Primária/tratamento farmacológico , Envelhecimento , Animais , Hormônio Antimülleriano/metabolismo , Senescência Celular/efeitos dos fármacos , Homólogo 5 da Proteína Cromobox , Proteínas Cromossômicas não Histona/metabolismo , Cicloexenos/toxicidade , Citocinas/sangue , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Disruptores Endócrinos/toxicidade , Estradiol/farmacologia , Estradiol/uso terapêutico , Estrogênios/metabolismo , Ciclo Estral/efeitos dos fármacos , Feminino , Hormônio Foliculoestimulante/sangue , Proteína HMGA1a/genética , Proteína HMGA1a/metabolismo , Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Histonas/metabolismo , Hormônio Luteinizante/sangue , Medicina Tradicional Chinesa , Camundongos Endogâmicos ICR , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/metabolismo , Compostos de Vinila/toxicidadeRESUMO
The flySAM/CRISPRa system has recently emerged as a powerful tool for gain-of-function studies in Drosophila melanogaster This system includes Gal4/UAS-driven dCas9 activators and U6 promoter-controlled sgRNA. Having established dCas9 activators superior to other combinations, to further enhance the efficiency of the targeting activators we systematically optimized the parameters of the sgRNA. Interestingly, the most efficient sgRNAs were found to accumulate in the region from -150bp to -450bp upstream of the transcription start site (TSS), and the activation efficiency showed a strong positive correlation with the GC content of the sgRNA targeting sequence. In addition, the target region is dominant to the GC content, as sgRNAs targeting areas beyond -600bp from the TSS lose efficiency even when containing 75% GC. Surprisingly, when comparing the activities of sgRNAs targeting to either DNA strand, sgRNAs targeting to the non-template strand outperform those complementary to the template strand, both in cells and in vivo In summary, we define criteria for sgRNA design which will greatly facilitate the application of CRISPRa in gain-of-function studies.
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Drosophila melanogaster , Drosophila , Animais , Composição de Bases , Sistemas CRISPR-Cas , Drosophila/genética , Drosophila melanogaster/genética , Regiões Promotoras Genéticas , RNA Guia de Cinetoplastídeos/genética , Sítio de Iniciação de TranscriçãoRESUMO
Sirtuin 6 (SIRT6), as a NAD + -dependent deacetylase, plays an indispensable role in the regulation of health and physiology. Loss of SIRT6 causes spontaneous colitis in mice and makes intestinal epithelial cells prone to stress. However, whether SIRT6 overexpression increases resistance to colitis remains unknown. Here, in vivo results demonstrated that SIRT6 overexpression attenuates DSS-induced colitis in terms of clinical manifestations, histopathological damage, loss of tight junction function and imbalanced intestinal microenvironment. Additionally, we also found that the activation of NF-κB and c-Jun induced by DSS is diminished by SIRT6 overexpression. Furthermore, SIRT6 may regulate TAK1 to inhibit NF-κB and c-Jun signaling. Thus, our findings highlight the protective effect of SIRT6 on colon, further supporting the perspective that SIRT6 may be a therapeutic target for intestine injury under stress.
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Colite/metabolismo , Sirtuínas/biossíntese , Animais , Colite/induzido quimicamente , Colite/genética , Colite/prevenção & controle , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Quinase 10 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 10 Ativada por Mitógeno/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Transdução de Sinais , Sirtuínas/genética , Sirtuínas/metabolismoRESUMO
Despite tremendous importance in catalysis, the design of oxide-metal interface has been hampered by the limited understanding of the nature of interfacial sites and the oxide-metal interaction (OMI). Through construction of well-defined Cu2O/Pt, Cu2O/Ag and Cu2O/Au interfaces, we find that Cu2O nanostructures (NSs) on Pt exhibit much lower thermal stability than on Ag and Au, although they show the same structure. The activities of these interfaces are compared for CO oxidation and follow the order of Cu2O/Pt > Cu2O/Au > Cu2O/Ag. OMI is found to determine the activity and stability of supported Cu2O NSs, which could be described by the formation energy of interfacial oxygen vacancy. Further, electronic interaction between Cu+ and metal substrates is found center to OMI, where the d band center could be used as a key descriptor. Our study provides insight for OMI and for the development of Cu-based catalysts for low temperature oxidation reactions.
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LLC-1903, a novel anticancer compound, was synthesized by optimizing the structure, which was derived from altering the leaving group of lobaplatin. It has an excellent in vitro anti-cancer activity, high water solubility, high stability in solution and low in vivo toxicity according to our former study.The plasma pharmacokinetics (PK) and tissue distribution of LLC-1903 and lobaplatin in rats were determined after intravenous administration of a single dose (0.06 mmol/kg body weight). Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the concentration of platinum (Pt) in plasma and tissue samples.Most PK parameters of the Pt in LLC-1903 showed a significant difference from those of lobaplatin. The plasma level of LLC-1903 is only half of that of lobaplatin (p < 0.01) which could be the direct result of faster drug clearance. The tissue distribution showed that both LLC-1903 and lobaplatin were mainly found in the liver and kidney, and less in other organs. At four time points (0.083, 0.5, 1 and 4 h) after administration, the tissue concentrations of LLC-1903 were almost always significantly higher than those of lobaplatin (p < 0.05 or p < 0.01).