RESUMO
BACKGROUND: The orchid industry has seen a recent surge in export values due to the floral morphology and versatile applications of orchids in various markets for medicinal, food additive, and cosmetic usages. However, plant-related diseases, including the yellow leaf disease caused by Fusarium solani, have caused significant losses in the production value of Phalaenopsis (up to 30%). RESULTS: In this study, 203 Phalaenopsis cultivars were collected from 10 local orchid nurseries, and their disease severity index and correlation with flower size were evaluated. Larger flowers had weaker resistance to yellow leaf disease, and smaller flowers had stronger resistance. For the genetic relationship of disease resistance to flower size, the genetic background of all cultivars was assessed using OrchidWiz Orchid Database Software and principal component analysis. In addition, we identified the orthologous genes of BraTCP4, namely PeIN6, PeCIN7, and PeCIN8, which are involved in resistance to pathogens, and analyzed their gene expression. The expression of PeCIN8 was significantly higher in the most resistant cultivars (A7403, A11294, and A2945) relative to the most susceptible cultivars (A10670, A6390, and A10746). CONCLUSIONS: We identified a correlation between flower size and resistance to yellow leaf disease in Phalaenopsis orchids. The expression of PeCIN8 may regulate the two traits in the disease-resistant cultivars. These findings can be applied to Phalaenopsis breeding programs to develop resistant cultivars against yellow leaf disease.
Assuntos
Orchidaceae , Orchidaceae/genética , Orchidaceae/metabolismo , Melhoramento Vegetal , Flores/genética , Flores/metabolismo , Folhas de Planta/genética , FenótipoRESUMO
INTRODUCTION: Eleutherococcus senticosus fruit (ESF) is a natural health supplement resource that has been extensively applied as a tonic for the nervous system. The structures and neural bioactivities of triterpenoid saponins (TS), which are the major constituents of ESF, have not been comprehensively analyzed thus far. OBJECTIVE: We conducted a complete in-depth MS/MS molecular networking (MN)-based targeted analysis of TS from the crude extract of ESF and investigated its neuroprotective value. METHODS: An MS/MS MN-guided strategy was used to rapidly present a series of precursor ions (PIs) of TS in a compound cluster as TS-targeted information used in the discovery and characterization of TS. In addition, a prepared TS-rich fraction of ESF was assayed for its restraining effects on ß-amyloid-induced inhibition of neurite outgrowth. RESULTS: A total of 87 TS were discovered using a PI tracking strategy, 28 of which were characterized as potentially undescribed structures according to their high-resolution MS values. Furthermore, the TS-rich fraction can significantly reduce ß-amyloid-induced damage to neural networks by promoting the outgrowth of neurites and axons. CONCLUSION: Our findings reveal the richness of TS in ESF and will accelerate their application in the treatment of neurodegenerative diseases.
Assuntos
Eleutherococcus , Saponinas , Triterpenos , Espectrometria de Massas em Tandem , Extratos Vegetais/química , Eleutherococcus/química , Saponinas/química , Frutas/química , Triterpenos/análiseRESUMO
Mammalian telomere lengths are primarily regulated by telomerase, a ribonucleoprotein consisting of a reverse transcriptase (TERT) and an RNA subunit (TERC). TERC is constitutively expressed in all cells, whereas TERT expression is temporally and spatially regulated, such that in most adult somatic cells, TERT is inactivated and telomerase activity is undetectable. Most tumor cells activate TERT as a mechanism for preventing progressive telomere attrition to achieve proliferative immortality. Therefore, inactivating TERT has been considered to be a promising means of cancer therapy. Here we applied the CRISPR/Cas9 gene editing system to target the TERT gene in cancer cells. We report that disruption of TERT severely compromises cancer cell survival in vitro and in vivo. Haploinsufficiency of TERT in tumor cells is sufficient to result in telomere attrition and growth retardation in vitro. In vivo, TERT haploinsufficient tumor cells failed to form xenograft after transplantation to nude mice. Our work demonstrates that gene editing-mediated TERT knockout is a potential therapeutic option for treating cancer.
Assuntos
Técnicas de Inativação de Genes/métodos , Telomerase/genética , Telomerase/metabolismo , Neoplasias do Colo do Útero/patologia , Animais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Feminino , Haploinsuficiência , Células HeLa , Humanos , Mutação INDEL , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismoRESUMO
BACKGROUND: Orchids produce a colorless protocorm by symbiosis with fungi upon seed germination. For mass production of orchids, the prevailing approaches are both generation of protocorm-like bodies (PLBs) from callus and multiplication of adventitious buds on inflorescence. However, somaclonal variations occur during micropropagation. RESULTS: We isolated the two most expressed transposable elements belonging to P Instability Factor (PIF)-like transposons. Among them, a potential autonomous element was identified by similarity analysis against the whole-genome sequence of Phalaenopsis equestris and named PePIF1. It contains a 19-bp terminal inverted repeat flanked by a 3-bp target site duplication and two coding regions encoding ORF1- and transposase-like proteins. Phylogenetic analysis revealed that PePIF1 belongs to a new P-lineage of PIF. Furthermore, two distinct families, PePIF1a and PePIF1b, with 29 and 37 putative autonomous elements, respectively, were isolated, along with more than 3000 non-autonomous and miniature inverted-repeat transposable element (MITE)-like elements. Among them, 828 PePIF1-related elements were inserted in 771 predicted genes. Intriguingly, PePIF1 was transposed in the somaclonal variants of Phalaenopsis cultivars, as revealed by transposon display, and the newly inserted genes were identified and sequenced. CONCLUSION: A PIF-like element, PePIF1, was identified in the Phalaenopsis genome and actively transposed during micropropagation. With the identification of PePIF1, we have more understanding of the Phalaenopsis genome structure and somaclonal variations during micropropagation for use in orchid breeding and production.
Assuntos
Elementos de DNA Transponíveis/genética , Orchidaceae/genética , Filogenia , Genoma de Planta/genética , Mutagênese Insercional/genética , Fases de Leitura Aberta , Sequências Repetidas Terminais/genética , Transposases/genéticaRESUMO
Histone modifications are associated with transcriptional regulation by diverse transcription factors. Genome-wide correlation studies have revealed that histone activation marks and repression marks are associated with activated and repressed gene expression, respectively. Among the histone activation marks is histone H3 K79 methylation, which is carried out by only a single methyltransferase, disruptor of telomeric silencing-1-like (DOT1L). We have been studying thyroid hormone (T3)-dependent amphibian metamorphosis in two highly related species, the pseudo-tetraploid Xenopus laevis and diploid Xenopus tropicalis, as a model for postembryonic development, a period around birth in mammals that is difficult to study. We previously showed that H3K79 methylation levels are induced at T3 target genes during natural and T3-induced metamorphosis and that Dot1L is itself a T3 target gene. These suggest that T3 induces Dot1L expression, and Dot1L in turn functions as a T3 receptor (TR) coactivator to promote vertebrate development. We show here that in cotransfection studies or in the reconstituted frog oocyte in vivo transcription system, overexpression of Dot1L enhances gene activation by TR in the presence of T3. Furthermore, making use of the ability to carry out transgenesis in X. laevis and gene knockdown in X. tropicalis, we demonstrate that endogenous Dot1L is critical for T3-induced activation of endogenous TR target genes while transgenic Dot1L enhances endogenous TR function in premetamorphic tadpoles in the presence of T3. Our studies thus for the first time provide complementary gain- and loss-of functional evidence in vivo for a cofactor, Dot1L, in gene activation by TR during vertebrate development.-Wen, L., Fu, L., Shi, Y.-B. Histone methyltransferase Dot1L is a coactivator for thyroid hormone receptor during Xenopus development.
Assuntos
Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Metamorfose Biológica/fisiologia , Metiltransferases/biossíntese , Receptores dos Hormônios Tireóideos/biossíntese , Proteínas de Xenopus/biossíntese , Animais , Histonas/genética , Histonas/metabolismo , Metiltransferases/genética , Receptores dos Hormônios Tireóideos/genética , Proteínas de Xenopus/genética , Xenopus laevisRESUMO
A toxicoproteomic study was performed on liver of rats treated with retrorsine (RTS), a representative hepatotoxic pyrrolizidine alkaloid at a toxic dose (140 mg/kg) known to cause severe acute hepatotoxicity. By comparing current data with our previous findings in mild liver lesions of rats treated with a lower dose of RTS, seven proteins and three toxicity pathways of vascular endothelial cell death, which was further verified by observed sinusoidal endothelial cell losses, were found uniquely associated with retrorsine-induced hepatotoxicity. This toxicoproteomic study of acute pyrrolizidine alkaloid intoxication lays a foundation for future investigation to delineate molecular mechanisms of pyrrolizidine alkaloid-induced hepatotoxicity.
Assuntos
Antineoplásicos Fitogênicos/intoxicação , Fígado/efeitos dos fármacos , Proteoma/efeitos dos fármacos , Alcaloides de Pirrolizidina/intoxicação , Animais , Fígado/metabolismo , Masculino , Proteoma/metabolismo , Proteômica , Ratos , Ratos Sprague-Dawley , Testes de ToxicidadeRESUMO
Gynostemma pentaphyllum saponins (GpS) have been shown to have anti-cancer activity. However, the underlying mechanisms remain unclear. In this study, we used the Apc(Min) (/+) colorectal cancer (CRC) mouse model to investigate the anti-cancer effect of GpS and we demonstrated that GpS treatment could significantly reduce the number and size of intestinal polyps in Apc(Min) (/+) mice. In order to identify the potential targets and mechanisms involved, a comparative proteomics analysis was performed and 40 differentially expressed proteins after GpS treatment were identified. Bioinformatics analyses suggested a majority of these proteins were involved in processes related to cellular redox homeostasis, and predicted Raf-1 as a potential target of GpS. The upregulation of two proteins known to be involved in redox homeostasis, peroxiredoxin-1 (Prdx1) and peroxiredoxin-2 (Prdx2), and the downregulation of Raf-1 were validated using Western blot analysis. After further investigation of the associated signaling networks, we postulated that the anti-cancer effect of GpS was mediated through the upregulation of Prdx1 and Prdx2, suppression of Ras, RAF/MEK/ERK/STAT, PI3K/AKT/mTOR signaling and modulation of JNK/p38 MAPK signaling. We also examined the potential combinatorial effect of GpS with the chemotherapeutic 5-fluorouracil (5-FU) and found that GpS could enhance the anti-cancer efficacy of 5-FU, further suppressing the number of polyps in Apc(Min/+) mice. Our findings highlight the potential of GpS as an anti-cancer agent, the potential mechanisms of its anti-cancer activities, and its effect as an adjuvant of 5-FU in the chemotherapy of CRC.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/farmacologia , Saponinas/farmacologia , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias Colorretais/patologia , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Fluoruracila/uso terapêutico , Gynostemma/química , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteoma/metabolismo , Saponinas/uso terapêutico , Transdução de Sinais , Carga TumoralRESUMO
Thyroid hormone (TH) is critical for vertebrate postembryonic development, a period around birth in mammals when plasma TH levels are high. Interestingly, TH receptors (TRs), especially TRα, are expressed prior to the synthesis and secretion of zygotic TH, suggesting the existence of unliganded TR during development. However, the role of unliganded TR during mammalian development has been difficult to study, in part due to the relatively weak phenotype of TR knockout mice. Amphibian metamorphosis resembles postembryonic development in mammals and is controlled by TH via TRs. Like in mammals, TRα gene is highly activated and is the major TR expressed prior to the synthesis of endogenous TH. By using TALEN (transcriptional activator like effector nucleases)-mediated gene editing approach, we and others have now shown that unliganded TRα has two independent functions during Xenopus premetamorphosis, i.e. inhibiting growth rate and slowing development. Furthermore, molecular and transgenic studies have shown that unliganded TRα accomplishes these via the recruitment of histone deacetylase (HDAC)-containing corepressor complexes to repress the expression of TH-inducible genes.
Assuntos
Metamorfose Biológica/fisiologia , Receptores alfa dos Hormônios Tireóideos/metabolismo , Proteínas de Xenopus/metabolismo , Animais , Camundongos , Camundongos Knockout , Receptores alfa dos Hormônios Tireóideos/genética , Proteínas de Xenopus/genética , Xenopus laevisRESUMO
Histone methylations have been implicated to play important roles in diverse cellular processes. Of particular interest is the methylation of histone H3K79, which is catalyzed by an evolutionarily conserved methyltransferase, disruptor of telomeric silencing (Dot1)-like (Dot1L). To investigate the role of Dot1L during vertebrate development, we have generated a Dot1L-specific transcription activator-like effector nuclease (TALEN) nuclease to knockdown endogenous Dot1L in Xenopus tropicalis, a diploid species highly related to the well-known developmental model Xenopus laevis, a pseudotetraploid amphibian. We show that the TALEN was extremely efficient in mutating Dot1L when expressed in fertilized eggs, creating essentially Dot1L knockout embryos with little H3K79 methylation. Importantly, we observed that Dot1L knockdown had no apparent effect on embryogenesis because normally feeding tadpoles were formed, consistent with the lack of maternal Dot1L expression. On the other hand, Dot1L knockdown severely retarded the growth of the tadpoles and led to tadpole lethality prior to metamorphosis. These findings suggest that Dot1L and H3K79 methylation play an important role for tadpole growth and development prior to metamorphosis into a frog. Our findings further reveal interesting similarities and differences between Xenopus and mouse development and suggest the existence of 2 separate phases of vertebrate development with distinct requirements for epigenetic modifications.
Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Histona-Lisina N-Metiltransferase/fisiologia , Transcrição Gênica , Proteínas de Xenopus/fisiologia , Xenopus/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados , Sequência de Bases , Proliferação de Células , Gonadotropina Coriônica/metabolismo , Epigênese Genética , Feminino , Histona Metiltransferases , Histonas/metabolismo , Masculino , Metilação , Dados de Sequência Molecular , MutaçãoRESUMO
Pyrrolizidine alkaloids (PAs) are a group of phytotoxins that can induce human liver injury, particularly hepatic sinusoidal obstruction syndrome (HSOS). To date, the molecular targets of PA-induced HSOS are largely unknown. In this study, retrorsine (RTS), a known hepatotoxic PA, was used as a representative PA for proteomic studies. Toxicological assessment demonstrated that 35 mg/kg RTS (designated as RTS-L) caused early lesions of HSOS at 24 h after dosing. A proteomic approach revealed 17 up-regulated and 31 down-regulated proteins in RTS-L-treated rats. Subsequently, bioinformatic analysis suggested that two proteins, carbamoyl-phosphate synthase (CPS1) (p < 0.05) and ATP synthase subunit beta (ATP5B) (p < 0.01) were associated with RTS-L intoxication. Using immunohistochemical staining, we further verified the down-regulation of CPS1 and ATP5B in RTS-L-treated rats. These findings indicated that CPS1 and ATP5B were altered in the RTS-induced early lesions of HSOS in rats, and therefore, these two proteins and their involved pathways might play important roles in the initiation of HSOS. To the best of our knowledge, our study using a proteomic approach combined with conventional toxicological assessment is the first systems toxicology study on PA-induced HSOS. The results of this study provide novel findings on protein profiles in response to PA exposure, which can serve as a starting point to further investigate potential protein targets and their interactions with PAs to induce HSOS.
Assuntos
Hepatopatia Veno-Oclusiva/induzido quimicamente , Proteômica , Alcaloides de Pirrolizidina/toxicidade , Animais , Análise por Conglomerados , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Y chromosome deletion and karyotype abnormalities are commonly associated with congenital non-obstructive azoospermia, impairing spermatogenesis. Specifically, the deletion of the Y chromosome Azoospermia factor a (AZFa) has been identified in infertile males with severely impaired spermatogenesis. AZFa, encompassing megabase-scale of the Y chromosome region, poses challenges in modeling AZFa deletion-related male infertility using gene editing tools. Here, we successfully created an AZFa-deleted human embryonic stem cell line utilizing the CRISPR/Cas9 gene editing tool. Our analysis indicates the AZFa-deleted stem cell line holds promise for differentiation into ectoderm, mesoderm, and endoderm, highlighting its potential for further comprehensive study.
Assuntos
Células-Tronco Embrionárias Humanas , Humanos , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Masculino , Linhagem Celular , Cromossomos Humanos Y/genética , Diferenciação Celular , Sistemas CRISPR-Cas , Deleção Cromossômica , Edição de GenesRESUMO
Lepidium meyenii Walp., also known as the "Peruvian national treasure", is a popular functional food in the daily lives of Peruvian people due to its bioactive with main polysaccharides. However, studies on polysaccharides isolated from Lepidium meyenii were few. Two new highly heterogeneous polysaccharides, MCP-1a and MCP-2b, were isolated and purified from the tuber of Lepidium meyenii. The structure characterization revealed that MCP-1a primarily consisted of D-Glc and had a molecular weight of 6.6 kDa. Its backbone was composed of 1,4,6-α-D-Glc, while branches feature T-α-L-Ara, 1,5-α-L-Ara, and T-α-D-Glc attached to the O-6 positions. MCP-2b was a rare arabinogalactan with a molecular weight of 49.4 kDa. Interestingly, the backbone of MCP-2b was composed of 1,6-ß-D-Gal, 1,3,6-ß-D-Gal with a few 1,3-ß-D-GlcpA-4-OMe units inserted. Side chains of MCP-2b were mainly composed of 1,3-ß-D-Gal, T-ß-D-Gal, T-α-L-Ara, 1,5-α-L-Ara, with trace amounts of 1,4-ß-D-Glc and T-ß-D-Glc. The bioactivity assay results revealed that MCP-1a and MCP-2b increased the release of NO, IL-1ß, TNF-α, and IL-6 from RAW 264.7 cells at concentrations ranging from 50 µg/mL to 400 µg/mL. Furthermore, MCP-1a and MCP-2b could promote the expression of key transcription factors (IκB-α, p-IκB-α, p65, and p-p65) in the NF-κB pathway, indicating that MCP-1a and MCP-2b had potential immunomodulatory activities.
Assuntos
Lepidium , NF-kappa B , Polissacarídeos , Transdução de Sinais , Lepidium/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Camundongos , NF-kappa B/metabolismo , Animais , Transdução de Sinais/efeitos dos fármacos , Células RAW 264.7 , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Peso Molecular , Citocinas/metabolismoRESUMO
Omics-based technologies have revolutionized our comprehension of microproteins encoded by ncRNAs, revealing their abundant presence and pivotal roles within complex functional landscapes. Here, we developed MicroProteinDB (http://bio-bigdata.hrbmu.edu.cn/MicroProteinDB), which offers and visualizes the extensive knowledge to aid retrieval and analysis of computationally predicted and experimentally validated microproteins originating from various ncRNA types. Employing prediction algorithms grounded in diverse deep learning approaches, MicroProteinDB comprehensively documents the fundamental physicochemical properties, secondary and tertiary structures, interactions with functional proteins, family domains, and inter-species conservation of microproteins. With five major analytical modules, it will serve as a valuable knowledge for investigating ncRNA-derived microproteins.
Assuntos
Bases de Dados de Proteínas , RNA não Traduzido , RNA não Traduzido/química , RNA não Traduzido/genética , Humanos , Proteínas/química , Animais , MicropeptídeosRESUMO
Peptide isoelectric focusing (IEF) is a common technique used in two-dimensional liquid chromatography tandem mass spectrometry (2D-LC-MS/MS) proteomic workflow, in which the tryptic peptide is first pre-fractionated based on pI values before being subjected to reverse phase LC-MS analysis. Although this method has been widely used by many research groups, a systemic study on the optimal conditions and fundamental parameters influencing the experimental outcomes has been lacking, including the effect of peptide extraction methods, the extent of pre-fractionation, and the choice of pH range. In this study, we compared the effect of different parameters on the numbers of peptides and proteins identified using two complex mouse proteomes. The results indicated that extraction of peptides from immobilized pH gradient (IPG) strips by sequential elution of increasingly organic solvents provided the highest number of peptide identification. In addition, we showed that approximately 45 more unique proteins were identified for every additional fraction collected during peptide IEF. Although narrow pH ranges provided higher resolution in peptide separation as expected, different pH ranges yielded similar numbers of peptide and protein identification. Overall, we demonstrated that the extraction solvent influenced the numbers of peptide and protein identification and quantitatively demonstrated the advantage of extensive fractionation and the performance of different pH ranges in practice.
Assuntos
Carcinoma Pulmonar de Lewis/química , Fragmentos de Peptídeos/isolamento & purificação , Proteoma/análise , Animais , Linhagem Celular Tumoral , Cromatografia Líquida , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Força Próton-Motriz , Microextração em Fase Sólida , Espectrometria de Massas em Tandem , Tripsina/químicaRESUMO
PURPOSE: The aim of this study is to investigate the involvement of DNA-dependent protein kinase (DNA-PK) in palmitate and oleate-induced lipid accumulation in hepatocytes. METHODS: We treated HepG2 with free fatty acids (FFA) (0.33 mM palmitate and 0.66 mM oleate) mixture to induce lipid accumulation. Cellular lipid was determined by Nile Red staining followed by flow cytometry detection as well as phase contrast and fluorescence microscope examination. Cell viability was detected by MTT assay. Apoptosis was detected by DAPI staining. Lipogenic gene expression was examined by real-time PCR at mRNA level and Western blotting at protein level. Promoter transcriptional activity was measured by dual luciferase assay. RESULTS: FFA treatment neither affected HepG2 cells viability nor induced DNA fragmentation, while induced cellular lipid accumulation was associated by the upregulation of sterol regulatory element-binding protein-1 (SREBP1) and fatty acid synthase (FAS) at both mRNA and protein levels. Interestingly, we also found that both the protein phosphatase 2A (PP2A) protein expression and DNA-PK activity were increased in these cells. Inhibition of PP2A by okadaic acid, knockdown of DNA-PK by siRNA or inhibition of DNA-PK by specific DNA-PK inhibitors curtailed the FFA-induced upregulations of the SREBP1 mRNA expression and the nuclear active SREBP1 protein expression, and reduced FFA-induced upregulation of FAS promoter transcriptional activity and lipid accumulation. CONCLUSION: This is the first time suggesting that inhibition of DNA-PK reduced FFA-induced lipid accumulation in hepatocytes. This finding might help us better understand non-alcoholic steatohepatitis pathogenesis.
Assuntos
Proteína Quinase Ativada por DNA/genética , Hepatócitos/efeitos dos fármacos , Ácido Oleico/efeitos adversos , Ácido Palmítico/efeitos adversos , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Proteína Quinase Ativada por DNA/metabolismo , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Células Hep G2 , Hepatócitos/patologia , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fosforilação , Regiões Promotoras Genéticas , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Regulação para CimaRESUMO
Twelve undescribed 15,16-seco-cycloartane triterpenoids, 15,16-seco-cimiterpenes C-N, as well as five previously reported analogs were isolated by NMR-tracking methods from the rhizomes of Cimicifuga acerina (Sieb. et Zucc.) Tanaka. Among them, 15,16-seco-cimiterpenes C-N were the first 15,16-seco-cycloartane triterpenoids featuring acetal or hemiacetal structures at C-15. The chemical structures of 15,16-seco-cimiterpenes C-N were determined based on comprehensive spectroscopic analysis, chemical method, and comparison with the previous literature data. After that, all these compounds were evaluated for their lipid-lowering effects on 3T3-L1 adipocytes.15,16-seco-cimiterpene D was found to exhibit a comparable reducing lipid effect at the concentration of 50 µM, with an inhibition rate at 35.96%.
Assuntos
Actaea , Cimicifuga , Triterpenos , Cimicifuga/química , Espectroscopia de Ressonância Magnética , Triterpenos/farmacologia , Triterpenos/química , Lipídeos , Estrutura MolecularRESUMO
BACKGROUND: In eukaryotic cells, DNA double strand breaks (DSB) are primarily repaired by canonical non-homologous end joining (c-NHEJ), homologous recombination (HR) and alternative NHEJ (alt-NHEJ). Zinc finger and SCAN domain containing 4 (ZSCAN4), sporadically expressed in 1-5% mouse embryonic stem cells (mESCs), is known to regulate genome stability by promoting HR. RESULTS: Here we show that ZSCAN4 promotes DNA repair by acting with Poly (ADP-ribose) polymerase 1 (PARP1), which is a key member of the alt-NHEJ pathway. In the presence of PARP1, ZSCAN4-expressing mESCs are associated with lower extent of endogenous or chemical induced DSB comparing to ZSCAN4-negative ones. Reduced DSBs associated with ZSCAN4 are abolished by PARP1 inhibition, achieved either through small molecule inhibitor or gene knockout in mESCs. Furthermore, PARP1 binds directly to ZSCAN4, and the second âº-helix and the fourth zinc finger motif of ZSCAN4 are critical for this binding. CONCLUSIONS: These data reveal that PARP1 and ZSCAN4 have a protein-protein interaction, and shed light on the molecular mechanisms by which ZSCAN4 reduces DSB in mESCs.
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Four polysaccharides (MCPa, MCPb, MCPc, MCPd) were obtained from Lepidium meyenii Walp. Their structures were characterized by chemical and instrumental methods including total sugar, uronic acid and protein content determination, UV, IR and NMR spectroscopy, as well as monosaccharide composition determination and methylation analyses. Four polysaccharides were a group of glucans with different molecular weights ranging from 3.12 to 14.4 kDa, and shared a similar backbone chain consisting of (1â4)-glucose linkages with branches attached to C-3 and C-6. Furthermore, bioactivity assay showed that MCPs had concentration-dependent inhibitory activity on α-glucosidase. MCPb (Mw = 10.1 kDa) and MCPc (Mw = 5.62 kDa) with moderate molecular weights exhibited higher inhibitory activity compared with MCPa and MCPd.
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Introduction: Pathological angiogenesis, the abnormal or excessive generation of blood vessels, plays an important role in many diseases including cancer, diabetic retinopathy, psoriasis, and arthritis. Additionally, increasing evidence supports the close linkage between angiogenesis and inflammation. Snake venoms are a rich natural source of biologically active molecules and carry rich potential for the discovery of anti-angiogenic and anti-inflammatory modulators. Methods: Here, we isolated and purified a novel protein, ZK002, from the venom of the snake Deinagkistrodon acutus, and investigated its anti-angiogenic and anti-inflammatory activities and mechanisms. Results: ZK002 was identified as a 30 kDa heterodimeric protein of α and ß chains, which exhibited anti-angiogenic activity in various in vitro assays. Mechanistically, ZK002 inhibited activation of VEGF signaling and related mediators including eNOS, p38, LIMK, and HSP27. ZK002 also upregulated the metalloproteinase inhibitor TIMP3 and inhibited components of the VEGF-induced signaling cascade, PPP3R2 and SH2D2A. The anti-angiogenic activity of ZK002 was confirmed in multiple in vivo models. ZK002 could also inhibit the in vitro expression of pro-inflammatory cytokines, as well as in vivo inflammation in the carrageenin-induced edema rat model. Conclusion: Our findings highlight the potential for further development of ZK002 as a dual function therapeutic against diseases with involvement of pathogenic angiogenesis and chronic inflammation.
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Reynoutria multiflora roots are a classical herbal medicine with unique nourishing therapeutic effects. Anomalous vascular bundle (AVB) forming "cloudy brocade patterns" is a typical morphological feature of R. multiflora roots and has been empirically linked to its quality classification. However, scientific evidence, especially for AVB-specific specialised metabolites, has not been comprehensively revealed thus far. Herein, desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) analysis was applied to carry out an in situ analysis of specialised metabolites distributed specifically at the AVB and cork of R. multiflora roots. To enlarge the scope of compounds by DESI detection, various solvent systems including acetone, acetonitrile, methanol, and water were used to assist in the discoveries of 40 specialised metabolites with determined localization. A series of bioactive constituents including stilbenes, flavonoids, anthraquinones, alkaloids, and naphthalenes were found specifically around the brocade patterns. Notably, phospholipids were detected from R. multiflora roots by in situ analysis for the first time and were found mainly in the phloem of AVB (PAB). This is the first study to use gradient solvent systems in DESI-MSI analysis to locate the specialised metabolites distribution. The discovery of feature-specific compounds will bridge the empirical identification to precision quality control of R. multiflora roots.