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1.
Ecol Evol ; 13(8): e10377, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37554399

RESUMO

Changes in nitrogen (N) deposition and litter mixtures have been shown to influence ecosystem processes such as litter decomposition. However, the interactive effects of litter mixing and N-deposition on decomposition process in desert regions remain poorly identified. We assessed the simultaneous effects of both N addition and litter mixture on mass loss in a litterbag decomposition experiment using six native plants in single-species samples with diverse quality and 14-species combinations in the Gurbantunggut Desert under two N addition treatments (control and N addition). The N addition had no significant effect on decomposition rate of single-species litter (expect Haloxylon ammodendron), whereas litter mass loss and decomposition rate differed significantly among species, with variations positively correlated with initial phosphorus concentration and negatively correlated with initial lignin concentration. After 18 months, the average mass loss across litter mixtures did not overall differ from those predicted from single species either in control or N addition treatments, that is, mixing of different species had no non-additive effects on decomposition. The N addition, however, did modify the direction of mixture effects and interacted with incubation time. Added N transformed synergistic effects of litter mixtures to antagonistic effects on mass loss after 1 month of decomposition, while transforming neutral effects of litter mixture to synergistic effects after 6 months of decomposition. Our results demonstrated that initial chemical properties played an important role in litter decomposition, while no effects of litter mixture on decomposition process in this desert region. The N addition altered the litter mixture effects on mass loss with incubation time, implying that increased N deposition in the future may have profound effects on carbon turnover to a greater extent than previously thought in desert ecosystems.

2.
Front Cell Dev Biol ; 11: 1199519, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37261074

RESUMO

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are emerging as the leading causes of liver disease worldwide. These conditions can lead to cirrhosis, liver cancer, liver failure, and other related ailments. At present, liver transplantation remains the sole treatment option for end-stage NASH, leading to a rapidly growing socioeconomic burden. Kupffer cells (KCs) are a dominant population of macrophages that reside in the liver, playing a crucial role in innate immunity. Their primary function includes phagocytosing exogenous substances, presenting antigens, and triggering immune responses. Moreover, they interact with other liver cells during the pathogenesis of NAFLD, and this crosstalk may either delay or exacerbate disease progression. Stimulation by endogenous signals triggers the activation of KCs, resulting in the expression of various inflammatory factors and chemokines, such as NLRP3, TNF-α, IL-1B, and IL-6, and contributing to the inflammatory cascade. In the past 5 years, significant advances have been made in understanding the biological properties and immune functions of KCs in NAFLD, including their interactions with tissue molecules, underlying molecular mechanisms, signaling pathways, and relevant therapeutic interventions. Having a comprehensive understanding of these mechanisms and characteristics can have enormous potential in guiding future strategies for the prevention and treatment of NAFLD.

3.
Gene ; 866: 147349, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-36893874

RESUMO

To survive under harsh environments, embryonic development of Artemia was arrested at the gastrula stage and released as the diapause embryo. Cell cycle and metabolism were highly suppressed in this state of quiescence. However, cellular mechanisms underlying diapause remain largely unclear. In this study, we found that the expression level of a CT10 regulator of kinase-encoding gene (Ar-Crk) in diapause embryos was significantly lower than non-diapause embryos at the early embryogenetic stage of Artemia. Knockdown of Ar-Crk by RNA interference induced formation of diapause embryos, while the control group produced nauplii. Western blot analysis and metabolic assays revealed that the diapause embryos produced by Ar-Crk-knocked-down Artemia had similar characteristics of diapause markers, arrested cell cycle, and suppressed metabolism with those diapause embryos produced by natural oviparous Artemia. Transcriptomic analysis of Artemia embryos revealed knockdown of Ar-Crk induced downregulation of the aurora kinase A (AURKA) signaling pathway, as well as energetic and biomolecular metabolisms. Taken together, we proposed that Ar-Crk is a crucial factor in determining the process of diapause in Artemia. Our results provide insight into the functions of Crk in fundamental regulations such as cellular quiescence.


Assuntos
Artemia , Diapausa , Animais , Artemia/genética , Regulação para Baixo , Diapausa/genética , Divisão Celular , Ciclo Celular , Embrião não Mamífero/metabolismo
4.
Adv Cancer Res ; 158: 199-231, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36990533

RESUMO

The brine shrimp (Artemia), releases embryos that can remain dormant for up to a decade. Molecular and cellular level controlling factors of dormancy in Artemia are now being recognized or applied as active controllers of dormancy (quiescence) in cancers. Most notably, the epigenetic regulation by SET domain-containing protein 4 (SETD4), is revealed as highly conserved and the primary control factor governing the maintenance of cellular dormancy from Artemia embryonic cells to cancer stem cells (CSCs). Conversely, DEK, has recently emerged as the primary factor in the control of dormancy exit/reactivation, in both cases. The latter has been now successfully applied to the reactivation of quiescent CSCs, negating their resistance to therapy and leading to their subsequent destruction in mouse models of breast cancer, without recurrence or metastasis potential. In this review, we introduce the many mechanisms of dormancy from Artemia ecology that have been translated into cancer biology, and herald Artemia's arrival on the model organism stage. We show how Artemia studies have unlocked the mechanisms of the maintenance and termination of cellular dormancy. We then discuss how the antagonistic balance of SETD4 and DEK fundamentally controls chromatin structure and consequently governs CSCs function, chemo/radiotherapy resistance, and dormancy in cancers. Many key stages from transcription factors to small RNAs, tRNA trafficking, molecular chaperones, ion channels, and links with various pathways and aspects of signaling are also noted, all of which link studies in Artemia to those of cancer on a molecular and/or cellular level. We particularly emphasize that the application of such emerging factors as SETD4 and DEK may open new and clear avenues for the treatment for various human cancers.


Assuntos
Artemia , Neoplasias da Mama , Animais , Camundongos , Humanos , Feminino , Artemia/genética , Artemia/metabolismo , Epigênese Genética , Neoplasias da Mama/patologia , Transdução de Sinais , Células-Tronco Neoplásicas/patologia , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo
5.
Chromosoma ; 132(2): 89-103, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36939898

RESUMO

Although parthenogenesis is widespread in nature and known to have close relationships with bisexuality, the transitional mechanism is poorly understood. Artemia is an ideal model to address this issue because bisexuality and "contagious" obligate parthenogenesis independently exist in its congeneric members. In the present study, we first performed chromosome spreading and immunofluorescence to compare meiotic processes of Artemia adopting two distinct reproductive ways. The results showed that, unlike conventional meiosis in bisexual Artemia, meiosis II in parthenogenic Artemia is entirely absent and anaphase I is followed by a single mitosis-like equational division. Interspecific comparative transcriptomics showed that two central molecules in homologous recombination (HR), Dmc1 and Rad51, exhibited significantly higher expression in bisexual versus parthenogenetic Artemia. qRT-PCR indicated that the expression of both genes peaked at the early oogenesis and gradually decreased afterward. Knocking-down by RNAi of Dmc1 in unfertilized females of bisexual Artemia resulted in a severe deficiency of homologous chromosome pairing and produced univalents at the middle oogenesis stage, which was similar to that of parthenogenic Artemia, while in contrast, silencing Rad51 led to no significant chromosome morphological change. Our results indicated that Dmc1 is vital for HR in bisexual Artemia, and the deficiency of Dmc1 may be correlated with or even possibly one of core factors in the transition from bisexuality to parthenogenesis.


Assuntos
Artemia , Recombinases , Animais , Feminino , Recombinases/genética , Artemia/genética , Artemia/metabolismo , Bissexualidade , Meiose , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Partenogênese/genética , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo
6.
Biochem J ; 480(5): 385-401, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36852878

RESUMO

Doublesex (DSX) proteins are members of the Doublesex/mab-3-related (DMRT) protein family and play crucial roles in sex determination and differentiation among the animal kingdom. In the present study, we identified two Doublesex (Dsx)-like mRNA isoforms in the brine shrimp Artemia franciscana (Kellogg 1906), which are generated by the combination of alternative promoters, alternative splicing and alternative polyadenylation. The two transcripts exhibited sex-biased enrichment, which we termed AfrDsxM and AfrDsxF. They share a common region which encodes an identical N-terminal DNA-binding (DM) domain. RT-qPCR analyses showed that AfrDsxM is dominantly expressed in male Artemia while AfrDsxF is specifically expressed in females. Expression levels of both isoforms increased along with the developmental stages of their respective sexes. RNA interference with dsRNA showed that the knockdown of AfrDsxM in male larvae led to the appearance of female traits including an ovary-like structure in the original male reproductive system and an elevated expression of vitellogenin. However, silencing of AfrDsxF induced no clear phenotypic change in female Artemia. These results indicated that the male AfrDSXM may act as inhibiting regulator upon the default female developmental mode in Artemia. Furthermore, electrophoretic mobility shift assay analyses revealed that the unique DM domain of AfrDSXs can specifically bind to promoter segments of potential downstream target genes like AfrVtg. These data show that AfrDSXs play crucial roles in regulating sexual development in Artemia, and further provide insight into the evolution of sex determination/differentiation in sexual organisms.


Assuntos
Artemia , Isoformas de RNA , Animais , Masculino , Feminino , Artemia/genética , Isoformas de RNA/metabolismo , Processamento Alternativo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Diferenciação Sexual/genética
8.
Cell Rep ; 41(11): 111796, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36516755

RESUMO

Intestinal epithelial replenishment is fueled by continuously dividing intestinal stem cells (ISCs) resident at the crypt niche. However, the cell type(s) enabling replenishment upon damage and subsequent loss of whole crypts remain largely unclear. Using Set domain-containing protein 4 (Setd4), we identify a small population with reserve stem cell characteristics in the mouse intestine. Upon irradiation-induced injury, Setd4-expressing (Setd4+) cells survive radiation exposure and then activate to produce Sca-1-expressing cell types to restore the epithelial wall and regenerate crypts de novo via crypt fission. Setd4+ cells are confirmed to originate from the early fetal period, subsequently contributing to the development of embryonic gut and the establishment of postnatal crypts. Setd4+ cells are therefore represented as both originators and key regenerators of the intestine.


Assuntos
Células-Tronco Embrionárias , Intestinos , Camundongos , Animais , Proteínas/metabolismo , Mucosa Intestinal/metabolismo
9.
Stem Cell Reports ; 17(9): 2081-2096, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36027907

RESUMO

Cellular quiescence facilitates maintenance of neural stem cells (NSCs) and their subsequent regenerative functions in response to brain injury and aging. However, the specification and maintenance of NSCs in quiescence from embryo to adulthood remain largely unclear. Here, using Set domain-containing protein 4 (SETD4), an epigenetic determinant of cellular quiescence, we mark a small but long-lived NSC population in deep quiescence in the subventricular zone of adult murine brain. Genetic lineage tracing shows that SETD4+ cells appear before neuroectoderm formation and contribute to brain development. In the adult, conditional knockout of Setd4 resulted in quiescence exit of NSCs, generating newborn neurons in the olfactory bulb and contributing to damage repair. However, long period deletion of SETD4 lead to exhaustion of NSC reservoir or SETD4 overexpression caused quiescence entry of NSCs, leading to suppressed neurogenesis. This study reveals the existence of long-lived deep quiescent NSCs and their neurogenetic capacities beyond activation.


Assuntos
Células-Tronco Adultas , Células-Tronco Neurais , Células-Tronco Adultas/metabolismo , Animais , Ventrículos Laterais , Camundongos , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Neurônios
10.
Oncogene ; 41(18): 2624-2637, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35351996

RESUMO

Tumor therapeutics often target the primary tumor bulk but fail to eradicate therapy-resistant cancer stem cells (CSCs) in quiescent state. These can then become activated to initiate recurrence and/or metastasis beyond therapy. Here, we identified and isolated chemoradiotherapy-resistant CSCs in quiescent state with high capacity of tumor-initiation and tumorsphere formation from three types of breast tumors in mice. Experiments of knockdown and rescue revealed DEK, a nuclear protein, as essential for CSC activation. Exogenous DEK was then used to trigger quiescence exit of CSCs. ChIP-seq and ATAC-seq showed that DEK directly binds to chromatin, facilitating its genome-wide accessibility. The resulting epigenetic events upregulate the expression of cellular activation-related genes including MYC targets, whereas cellular quiescence-related genes including the p53 signaling pathway are silenced. However, twinned with DEK-induced activation, formerly resistant CSCs were then destroyed by chemotherapy in vitro. In mice, traditional chemoradiotherapy concurrent with the injection of DEK-containing exosomes resulted in eradication of primary tumors together with formerly resistant CSCs without recurrence or metastasis. Our findings advance knowledge of the mechanism of quiescent CSC activation and may provide novel clinical opportunities for removal of quiescence-linked therapy resistance.


Assuntos
Neoplasias da Mama , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Divisão Celular , Quimiorradioterapia , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Feminino , Humanos , Camundongos , Células-Tronco Neoplásicas/patologia , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Transdução de Sinais
11.
Phys Chem Chem Phys ; 23(33): 18125-18136, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34397065

RESUMO

Photocatalytic water splitting is a promising technology to solve serious energy and environmental problems. The PtS2 monolayer has been previously predicted to be a water splitting photocatalyst. But the high efficiency of carrier recombination in the monolayer results in poor photocatalytic performance. It is well known that the construction of van der Waals (vdW) heterojunctions can improve the photocatalytic performance of a monolayer. In this investigation, we constructed a PtS2/SnS2 vdW heterojunction and systematically investigated the influence of the doping position and doping ratio on its performance using density functional theory calculations. Interestingly, the band alignment transforms from Type-II to Type-I and from Type-I to Type-II when the S in SnS2 is replaced with Se in the PtS2/SnS2 vdW heterojunction and the S in PtS2 is replaced with Se in the PtS2/SnSe2 vdW heterojunction, respectively. More importantly, from the PtS2/SnS2 to PtSe2/SnSe2 vdW heterojunction, the decomposition of water also changes from semi-decomposed water to fully decomposed water. Furthermore, the results show that the direct Z-scheme photocatalytic mechanism exists in the PtSSe/SnSe2 vdW heterojunction by analysis of the migration paths of photoinduced electrons and holes. And compared with the PtS2/SnS2, the PtSSe/SnSe2 heterostructure exhibits better photocatalytic water splitting activities. These results can provide a direction that doping can improve the photocatalytic water splitting performance of heterojunction photocatalysts.

12.
Sci Rep ; 11(1): 12614, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131249

RESUMO

In the adult pancreas, the presence of progenitor or stem cells and their potential involvement in homeostasis and regeneration remains unclear. Here, we identify that SET domain-containing protein 4 (SETD4), a histone lysine methyltransferase, is expressed in a small cell population in the adult mouse pancreas. Genetic lineage tracing shows that during pancreatic development, descendants of SETD4+ cells make up over 70% of pancreatic cells and then contribute to each pancreatic lineage during pancreatic homeostasis. SETD4+ cells generate newborn acinar cells in response to cerulein-induced pancreatitis in acinar compartments. Ablation of SETD4+ cells compromises regeneration of acinar cells, in contrast to controls. Our findings provide a new cellular narrative for pancreatic development, homeostasis and response to injury via a small SETD4+ cell population. Potential applications may act to preserve pancreatic function in case of pancreatic disease and/or damage.


Assuntos
Metiltransferases/genética , Pâncreas/metabolismo , Pancreatite/genética , Regeneração/genética , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Linhagem da Célula/genética , Ceruletídeo/toxicidade , Modelos Animais de Doenças , Homeostase/efeitos dos fármacos , Homeostase/genética , Humanos , Camundongos , Pâncreas/crescimento & desenvolvimento , Pâncreas/lesões , Pâncreas/patologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
13.
Sci Rep ; 11(1): 11603, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34079011

RESUMO

Blood vessels in the adult mammal exist in a highly organized and stable state. In the ischemic heart, limited expansion capacity of the myocardial vascular bed cannot satisfy demands for oxygen supply and the myocardium eventually undergoes irreversible damage. The predominant contribution of endogenous c-Kit+ cells is understood to be in the development and homeostasis of cardiac endothelial cells, which suggests potential for their targeting in treatments for cardiac ischemic injury. Quiescent cells in other tissues are known to contribute to the long-term maintenance of a cell pool, preserve proliferation capacity and, upon activation, facilitate tissue homeostasis and regeneration in response to tissue injury. Here, we present evidence of a Setd4-expressing quiescent c-Kit+ cell population in the adult mouse heart originating from embryonic stages. Conditional knock-out of Setd4 in c-Kit-CreERT2;Setd4f/f;Rosa26TdTomato mice induced an increase in vascular endothelial cells of capillaries in both neonatal and adult mice. We show that Setd4 regulates quiescence of c-Kit+ cells by the PI3K-Akt-mTOR signaling pathway via H4K20me3 catalysis. In myocardial infarction injured mice, Setd4 knock-out resulted in attenuated cardiomyocyte apoptosis, decreased infarction size and improved cardiac function. Lineage tracing in Setd4-Cre;Rosa26mT/mG mice showed that Setd4+ cells contribute to each cardiac lineage. Overall, Setd4 epigenetically controls c-Kit+ cell quiescence in the adult heart by facilitating heterochromatin formation via H4K20me3. Beyond activation, endogenous quiescent c-Kit+ cells were able to improve cardiac function in myocardial infarction injured mice via the neovascularization of capillaries.


Assuntos
Células Endoteliais/metabolismo , Epigênese Genética , Metiltransferases/genética , Infarto do Miocárdio/genética , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Animais , Apoptose , Capilares/crescimento & desenvolvimento , Divisão Celular , Proliferação de Células , Modelos Animais de Doenças , Ecocardiografia , Células Endoteliais/citologia , Feminino , Histonas/genética , Histonas/metabolismo , Integrases/genética , Integrases/metabolismo , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/citologia , Neovascularização Fisiológica , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
14.
J Cardiothorac Surg ; 16(1): 69, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823893

RESUMO

BACKGROUND: Left ventricular pseudoaneurysm due to early left ventricle rupture is a serious complication after cardiac surgery. Urgent surgery is recommended in most cases with a high mortality rate. Conservative treatment of a left ventricular pseudoaneurysm due to early left ventricle rupture is very rare. CASE PRESENTATION: We present a 61-year-old woman with left ventricular pseudoaneurysm after mitral valve replacement due to early left ventricle rupture. This patient was treated in a conservative approach. This patient had an uneventful recovery. She was in good condition and remained asymptomatic 3.5 years after mitral valve surgery. CONCLUSION: This case suggests that medical treatment left ventricular pseudoaneurysm patients has a limited but acceptable role in selected and unusual circumstances.


Assuntos
Falso Aneurisma/terapia , Aneurisma Cardíaco/terapia , Ruptura Cardíaca/complicações , Próteses Valvulares Cardíacas/efeitos adversos , Estenose da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Complicações Pós-Operatórias , Falso Aneurisma/diagnóstico , Tratamento Conservador/efeitos adversos , Feminino , Aneurisma Cardíaco/diagnóstico , Ruptura Cardíaca/diagnóstico , Ruptura Cardíaca/terapia , Ventrículos do Coração , Humanos , Pessoa de Meia-Idade
15.
Ying Yong Sheng Tai Xue Bao ; 31(11): 3631-3638, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33300712

RESUMO

A litterbag decomposition experiment was carried out in southern Gurbantunggut Desert, with four nitrogen treatments: N0(0 g N·m-2·a-1), N5(5 g N·m-2·a-1), N10(10 g N·m-2·a-1) and N20(20 g N·m-2·a-1). The aims were to examine the effects of exogenous nitrogen addition on decomposition rate and nutrient release of Tamarix ramosissima, Salicornia europaea and their mixture. Results showed that decomposition rates were significantly different among litter types. After 345 days, the decomposition rates of T. ramosissima, S. europaea and their mixture under different treatments were 0.64-0.70, 0.84-0.99 and 0.71-0.81 kg·kg-1·a-1, respectively. Both mono- and mixed-litters exhibited nutrient release during decomposition process, with the release rates being 60.6%-67.4%, 56.7%-62.6%, 57.4%-62.3%, 46.8%-63.0% for N, and 51.9%-77.9%, 59.9%-74.7%, 53.0%-79.9%, 52.3%-76.4% for P, respectively for the N0, N5, N10 and N20 treatments. Nitrogen addition did not affect litter decomposition rate. The dynamics of N and P during decomposition of different litter types showed different responses to nitrogen addition. Nitrogen addition inhibited N and P releases of S. europaea litter and P release of the mixed litter, but did not affect the nutrient release of T. ramosissima. The results suggested that nitrogen input would not promote litter decomposition in temperate desert ecosystems, but might retard the nutrient returning to soil system.


Assuntos
Ecossistema , Nitrogênio , Nutrientes , Folhas de Planta , Solo
16.
Artigo em Inglês | MEDLINE | ID: mdl-32117815

RESUMO

Bacterial infection remains one of the leading causes of death worldwide due to the continuous rise of multiple antibiotic-resistant bacteria. Focusing solely on bacteria as the drug targets is a major limitation inherent in the conventional antibiotic therapy. Recently, host-directed therapies have become such an innovative approach to modulate the host defense system and the interplay of innate and adaptive immunity. Our previous studies showed that memantine (MEM), an α7 nAChR antagonist, could efficiently block multi-drug resistant Escherichia coli-caused bacteremia and meningitis in a mouse model. However, the underlying mechanisms that govern the antibacterial effects of MEM are still unknown. In this study, we demonstrated that MEM is able to significantly suppress E. coli infection by enhancing E. coli-induced formation and release of NETs in vitro and in vivo. MEM could promote the trapping and bactericidal activities of the polymorphonuclear neutrophils (PMNs) in a manner dependent on α7 nAChR, since knockdown of this receptor noticeably reduces the survival ability of bacteria in PMNs while MEM no longer affects the survival of bacteria in PMNs. Our results also showed that when the expression of S100A9, an antiseptic protein, is inhibited, pathogen survival rates in PMNs increase significantly. MEM reverses this effect in a concentration-dependent manner. MEM stimulates the production of MPO, S100A9, and DNA in PMNs and accelerates the release of depolymerized chromatin fibers into the extracellular space, suggesting the formation of NETs. Taken together, our data suggest that MEM effectively blocks bacterial infection through the promotion of the antibacterial function of NETs induced by E. coli.


Assuntos
Armadilhas Extracelulares , Meningite , Animais , Escherichia coli , Memantina/farmacologia , Camundongos , Neutrófilos
17.
J Genet Genomics ; 47(11): 694-704, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33547005

RESUMO

Mitochondria are the central hub for many metabolic processes, including the citric acid cycle, oxidative phosphorylation, and fatty acid oxidation. Recent studies have identified a new mitochondrial protein family, Fam210, that regulates bone metabolism and red cell development in vertebrates. The model organism Caenorhabditis elegans has a Fam210 gene, y56a3a.22, but it lacks both bones and red blood cells. In this study, we report that Y56A3A.22 plays a crucial role in regulating mitochondrial protein homeostasis and reproduction. The nematode y56a3a.22 is expressed in various tissues, including the intestine, muscle, hypodermis, and germline, and its encoded protein is predominantly localized in mitochondria. y56a3a.22 deletion mutants are sterile owing to impaired oogenesis. Loss of Y56A3A.22 induced mitochondrial unfolded protein response (UPRmt), which is mediated through the ATFS-1-dependent pathway, in tissues such as the intestine, germline, hypodermis, and vulval muscle. We further show that infertility and UPRmt induces by Y56A3A.22 deficiency are not attributed to systemic iron deficiency. Together, our study reveals an important role of Y56A3A.22 in regulating mitochondrial protein homeostasis and oogenesis and provides a new genetic tool for exploring the mechanisms regulating mitochondrial metabolism and reproduction as well as the fundamental role of the Fam210 family.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Mitocôndrias/genética , Oogênese/genética , Fatores de Transcrição/genética , Resposta a Proteínas não Dobradas/genética , Animais , Osso e Ossos/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Eritrócitos/metabolismo , Feminino , Células Germinativas/crescimento & desenvolvimento , Células Germinativas/metabolismo , Humanos , Intestinos/crescimento & desenvolvimento , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Reprodução/genética , Transdução de Sinais/genética , Vulva/crescimento & desenvolvimento , Vulva/metabolismo
18.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3178-3186, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602870

RESUMO

Ziziphora bungeana is a kind of medicinal plants belongs to Labiatae,and it also a kind of geoherbs in Xinjiang. The main active ingredient linarin has a higher content in inflorescence than in other parts. In this study,high-throughput sequencing technology was used to reveal the transcriptome of the inflorescence of Z. bungeana,77 366 unigenes were acquired,of which 56 375 unigenes were annotated based on search of the database and classification. Through the analysis of metabolic pathways,sixty unigenes were probably encoding some enzymes involved in the flavonoid biosynthesis pathways. The contents of linarin in different parts were determined and the key genes were verified by qRT-PCR. The discovery provides the research basis for further analysis of the enzyme genes involved in the biosynthesis of the major flavonoid components in Z. bungeana.


Assuntos
Flavonoides/biossíntese , Lamiaceae/química , Transcriptoma , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala
19.
Cancer Res ; 79(18): 4729-4743, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308046

RESUMO

Quiescent cancer stem cells (CSC) play important roles in tumorigenesis, relapse, and resistance to chemoradiotherapy. However, the determinants of CSC quiescence and how they sustain themselves to generate tumors and relapse beyond resistance to chemoradiotherapy remains unclear. Here, we found that SET domain-containing protein 4 (SETD4) epigenetically controls breast CSC (BCSC) quiescence by facilitating heterochromatin formation via H4K20me3 catalysis. H4K20me3 localized to the promoter regions and regulated the expression of a set of genes in quiescent BCSCs (qBCSC). SETD4-defined qBCSCs were resistant to chemoradiotherapy and promoted tumor relapse in a mouse model. Upon activation, a SETD4-defined qBCSC sustained itself in a quiescent state by asymmetric division and concurrently produced an active daughter cell that proliferated to produce a cancer cell population. Single-cell sequence analysis indicated that SETD4+ qBCSCs clustered together as a distinct cell type within the heterogeneous BCSC population. SETD4-defined quiescent CSCs were present in multiple cancer types including gastric, cervical, ovarian, liver, and lung cancers and were resistant to chemotherapy. SETD4-defined qBCSCs had a high tumorigenesis potential and correlated with malignancy and chemotherapy resistance in clinical breast cancer patients. Taken together, the results from our previous study and current study on six cancer types reveal an evolutionarily conserved mechanism of cellular quiescence epigenetically controlled by SETD4. Our findings provide insights into the mechanism of tumorigenesis and relapse promoted by SETD4-defined quiescent CSCs and have broad implications for clinical therapies. SIGNIFICANCE: These findings advance our knowledge on the epigenetic determinants of quiescence in cancer stem cell populations and pave the way for future pharmacologic developments aimed at targeting drug-resistant quiescent stem cells.


Assuntos
Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Epigenômica , Metiltransferases/metabolismo , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Fase de Repouso do Ciclo Celular , Animais , Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/patologia , Carcinoma Basocelular/terapia , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Quimiorradioterapia , Feminino , Humanos , Metiltransferases/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/terapia , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Domínios Proteicos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Biochem J ; 476(12): 1753-1769, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31189566

RESUMO

To cope with harsh environments, the Artemia shrimp produces gastrula embryos in diapause, a state of obligate dormancy, having cellular quiescence and suppressed metabolism. The mechanism behind these cellular events remains largely unknown. Here, we study the regulation of cell quiescence using diapause embryos of Artemia We found that Artemia DEK (Ar-DEK), a nuclear factor protein, was down-regulated in the quiescent cells of diapause embryos and enriched in the activated cells of post-diapause embryos. Knockdown of Ar-DEK induced the production of diapause embryos whereas the control Artemia released free-swimming nuaplii. Our results indicate that Ar-DEK correlated with the termination of cellular quiescence via the increase in euchromatin and decrease in heterochromatin. The phenomena of quiescence have many implications beyond shrimp ecology. In cancer cells, for example, knockdown of DEK also induced a short period of cellular quiescence and increased resistance to environmental stress in MCF-7 and MKN45 cancer cell lines. Analysis of RNA sequences in Artemia and in MCF-7 revealed that the Wnt and AURKA signaling pathways were all down-regulated and the p53 signaling pathway was up-regulated upon inhibition of DEK expression. Our results provide insight into the functions of Ar-DEK in the activation of cellular quiescence during diapause formation in Artemia.


Assuntos
Artemia/embriologia , Proteínas de Artrópodes/biossíntese , Diapausa/fisiologia , Embrião não Mamífero/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Receptores da Família Eph/biossíntese , Via de Sinalização Wnt/fisiologia , Animais , Artemia/genética , Proteínas de Artrópodes/genética , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Humanos , Células MCF-7 , Receptores da Família Eph/genética
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