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1.
Appl Environ Microbiol ; 90(5): e0014524, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38578096

RESUMO

The bacterium Natranaerobius thermophilus is an extremely halophilic alkalithermophile that can thrive under conditions of high salinity (3.3-3.9 M Na+), alkaline pH (9.5), and elevated temperature (53°C). To understand the molecular mechanisms of salt adaptation in N. thermophilus, it is essential to investigate the protein, mRNA, and key metabolite levels on a molecular basis. Based on proteome profiling of N. thermophilus under 3.1, 3.7, and 4.3 M Na+ conditions compared to 2.5 M Na+ condition, we discovered that a hybrid strategy, combining the "compatible solute" and "salt-in" mechanisms, was utilized for osmotic adjustment dur ing the long-term salinity adaptation of N. thermophilus. The mRNA level of key proteins and the intracellular content of compatible solutes and K+ support this conclusion. Specifically, N. thermophilus employs the glycine betaine ABC transporters (Opu and ProU families), Na+/solute symporters (SSS family), and glutamate and proline synthesis pathways to adapt to high salinity. The intracellular content of compatible solutes, including glycine betaine, glutamate, and proline, increases with rising salinity levels in N. thermophilus. Additionally, the upregulation of Na+/ K+/ H+ transporters facilitates the maintenance of intracellular K+ concentration, ensuring cellular ion homeostasis under varying salinities. Furthermore, N. thermophilus exhibits cytoplasmic acidification in response to high Na+ concentrations. The median isoelectric points of the upregulated proteins decrease with increasing salinity. Amino acid metabolism, carbohydrate and energy metabolism, membrane transport, and bacterial chemotaxis activities contribute to the adaptability of N. thermophilus under high salt stress. This study provides new data that support further elucidating the complex adaptation mechanisms of N. thermophilus under multiple extremes.IMPORTANCEThis study represents the first report of simultaneous utilization of two salt adaptation mechanisms within the Clostridia class in response to long-term salinity stress.


Assuntos
Proteínas de Bactérias , Potássio , Estresse Salino , Potássio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Adaptação Fisiológica , Salinidade
2.
Environ Microbiol ; 25(10): 1967-1987, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37271582

RESUMO

The moderate halophilic bacterium Alkalicoccus halolimnae BZ-SZ-XJ29T exhibits optimum growth over a wide range of NaCl concentrations (8.3-12.3%, w/v; 1.42-2.1 mol L-1 ). However, its adaptive mechanisms to cope with high salt-induced osmotic stress remain unclear. Using TMT-based quantitative proteomics, the cellular proteome was assessed under low (4% NaCl, 0.68 mol L-1 NaCl, control (CK) group), moderate (8% NaCl, 1.37 mol L-1 NaCl), high (12% NaCl, 2.05 mol L-1 NaCl), and extremely high (16% NaCl, 2.74 mol L-1 NaCl) salinity conditions. Digital droplet PCR confirmed the transcription of candidate genes related to salinity. A. halolimnae utilized distinct adaptation strategies to cope with different salinity conditions. Mechanisms such as accumulating different amounts and types of compatible solutes (i.e., ectoine, glycine betaine, glutamate, and glutamine) and the uptake of glycine betaine and glutamate were employed to cope with osmotic stress. Ectoine synthesis and accumulation were critical to the salt adaptation of A. halolimnae. The expression of EctA, EctB, and EctC, as well as the intracellular accumulation of ectoine, significantly and consistently increased with increasing salinity. Glycine betaine and glutamate concentrations remained constant under the four NaCl concentrations. The total content of glutamine and glutamate maintained a dynamic balance and, when exposed to different salinities, may play a role in low salinity-induced osmoadaptation. Moreover, cellular metabolism was severely affected at high salt concentrations, but the synthesis of amino acids, carbohydrate metabolism, and membrane transport related to haloadptation was preserved to maintain cytoplasmic concentration at high salinity. These findings provide insights into the osmoadaptation mechanisms of moderate halophiles and can serve as a theoretical underpinning for industrial production and application of compatible solutes.


Assuntos
Diamino Aminoácidos , Salinidade , Betaína/metabolismo , Cloreto de Sódio/metabolismo , Glutamina , Proteômica , Pressão Osmótica , Diamino Aminoácidos/metabolismo , Glutamatos/metabolismo
3.
Am J Pathol ; 192(3): 503-517, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34896072

RESUMO

The overactivation of canonical Wnt/ß-catenin pathway is one of the main cascades for the initiation, progression, and recurrence of most human malignancies. As an indispensable coreceptor for the signaling transduction of the canonical Wnt/ß-catenin pathway, LRP5 is up-regulated and exerts a carcinogenic role in most types of cancer. However, its expression level and role in gastric cancer (GC) has not been clearly elucidated. The current work showed that LRP5 was overexpressed in GC tissues and the expression of LRP5 was positively associated with the advanced clinical stages and poor prognosis. Ectopic expression of LRP5 enhanced the proliferation, invasiveness, and drug resistance of GC cells in vitro, and accelerated the tumor growth in nude mice, through activating the canonical Wnt/ß-catenin signaling pathway and up-regulating aerobic glycolysis, thus increasing the energy supply for GC cells. Additionally, the expression of LRP5 and glycolysis-related genes showed an obviously positive correlation in GC tissues. By contrast, the exact opposite results were observed when the endogenous LRP5 was silenced in GC cells. Collectively, these results not only reveal the carcinogenic role of LRP5 during GC development through activating the canonical Wnt/ß-catenin and glycolysis pathways, but also provide a valuable candidate for the diagnosis and treatment of human GC.


Assuntos
Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Neoplasias Gástricas , Via de Sinalização Wnt , Animais , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células/genética , Glicólise , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Camundongos , Camundongos Nus , Neoplasias Gástricas/patologia , beta Catenina/metabolismo
4.
FASEB J ; 36(12): e22631, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36342387

RESUMO

Macroautophagy/autophagy is critically involved in the process of salivary gland (SG) diseases such as xerostomia, which has a serious impact on quality of life. KRT14+ progenitor cells are found to be the main progenitors for maintaining the ductal homeostasis of the submandibular SGs. In this study, we investigated the role of ATG5 in SG KRT14+ cells in mice and humans. Human labial salivary glands (LSG) from primary Sjogren's syndrome (pSS) and non-pSS patients (normal), and submandibular glands (SMG) from Atg5flox/flox ; Krt14-Cre (cKO) mice were used. ATG5+ KRT14+ and p62+ KRT14+ cells were detected by immunofluorescence staining in LSG. TUNEL, immunofluorescence, immunohistochemistry, and western blot were performed to detect cell death in SMG. Saliva was collected in 12-week-old (12 W) and 32-week-old (32 W) mice, then the concentration of calcium and buffering capacity were detected to analyze the function of SG. We found that LSG from pSS patients showed increased p62 and decreased ATG5 in KRT14+ cells. We further revealed that in 32 W, (1) the function of salivary glands was significantly impaired in cKO mice, (2) cell death increased in cKO mice, but cl-Caspase 3 was not significantly changed, and (3) cleaved gasdermin D increased and was highly expressed in KRT14+ cells of cKO mice. After applying a pyroptosis inhibitor to 32 W mice, the reduced saliva flow rate was rescued. In addition, pyroptosis was also found in KRT14+ cells of pSS patients. Collectively, our results indicate that Atg5 deficiency would induce pyroptosis in mice SG, which could lead to functional impairments of SG.


Assuntos
Síndrome de Sjogren , Humanos , Camundongos , Animais , Síndrome de Sjogren/metabolismo , Piroptose , Qualidade de Vida , Glândulas Salivares/metabolismo , Glândulas Salivares Menores/metabolismo , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Queratina-14/metabolismo
5.
Mol Cell Biochem ; 478(7): 1645-1658, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36729282

RESUMO

Hypoxic mesenchymal stem cell-derived extracellular vesicles (EVs) have been suggested as a promising therapy for various diseases. This study aims to determine the effect of EVs derived from bone marrow mesenchymal stem cells (BMMSCs) under hypoxia on lower limb ischemia and the underlying mechanism. Human BMMSCs were subjected to hypoxia or normoxia followed by the isolation of EVs. Nanoparticle trafficking analysis (NTA), transmission electron microscopy (TEM), and Western Blotting using corresponding markers were performed to confirm the EVs. The EVs from BMMSCs under hypoxia condition (Hyp-EVs) or normoxia condition (Nor-EVs) were subjected to hindlimb ischemia (HI) mice. MiR-34c expression in BMMSCs and BMMSC-EVs was detected. The role of miR-34c in regulating M2 macrophage polarization, as well as the target of miR-34c, were explored. HI mice with Hyp-EV treatment, as compared to the Nor-EV or the PBS group, had better blood flow and higher capillary density. MiR-34c expression was increased in BMMSCs, BMMSC-EVs, and the adductor muscle of HI mice. Hyp-EVs promoted the M2 macrophage polarization and anti-inflammatory cytokine production, and enhanced the blood flow and capillary density in HI mice, while the knockdown of miR-34c partly reversed these effects. PTEN is a target of miR-34c, and the PTEN silencing facilitated M2 macrophage polarization, whereas the inhibition of AKT signaling partly abolished the effect. Hyp-EVs promoted M2 macrophage polarization by delivering miR-34c via PTEN/AKT pathway, which could be a promising therapeutic strategy to ameliorate lower limb ischemia.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , MicroRNAs , Humanos , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Vesículas Extracelulares/metabolismo , Hipóxia/metabolismo , Isquemia/terapia , Isquemia/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Mesenquimais/metabolismo
6.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37917134

RESUMO

A novel alkaliphilic, Gram-stain-positive, moderately halophilic, rod-shaped, endospore-forming, motile, facultatively anaerobic bacterium (DQ-9T) was isolated from a sediment sample collected from Daqing oilfield in China, and characterized by a polyphasic taxonomic approach. Strain DQ-9T formed yellow pigment and grew occurred at salinities of 1-12 % (w/v) NaCl (optimum, 8 %) and at 10-40 °C (optimum, 30-35 °C), at pH 7.5-10.5 (optimum, pH 9.0-9.5). It was catalase-positive, but oxidase-negative. Based on the analysis of 16S rRNA gene sequences, DQ-9T was classified into the genus Salipaludibacillus and exhibited the highest similarities (98.37 %) to Salipaludibacillus neizhouensis JSM 071004T. Digital DNA-DNA hybridization and average nucleotide identity values between strain DQ-9T and the most closely related strain, S. neizhouensis DSM 19794T, were determined to be 72.0 and 21.6 %, respectively. The polar lipids were constituted by diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids (>5 %) comprised anteiso-C15 : 0, anteiso-C17 : 0, iso-C17 : 0, iso-C15 : 0 and C16 : 0. The cell-wall peptidoglycan contained meso-diaminopimelic acid, and menaquinone-7 was identified as the primary respiratory quinone. The DNA G+C content was 37.5 mol%. Through chemotaxonomic, physiological, and biochemical characterization, strain DQ-9T could be clearly distinguished from the closest Salipaludibacillus species. Based on provided data, strain DQ-9T is proposed to represent a novel species, Salipaludibacillus daqingensis sp. nov., within the genus Salipaludibacillus. The type strain is DQ-9T (=ACCC 60415T=KCTC 33936T).


Assuntos
Ácidos Graxos , Campos de Petróleo e Gás , Composição de Bases , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana
7.
Extremophiles ; 27(1): 8, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36976376

RESUMO

Droplet digital PCR (ddPCR) is being increasingly adopted for gene detection and quantification because of its higher sensitivity and specificity. According to previous observations and our laboratory data, it is essential to use endogenous reference genes (RGs) when investigating gene expression at the mRNA level under salt stress. This study aimed to select and validate suitable RGs for gene expression under salt stress using ddPCR. Six candidate RGs were selected based on the tandem mass tag (TMT)-labeled quantitative proteomics of Alkalicoccus halolimnae at four salinities. The expression stability of these candidate genes was evaluated using statistical algorithms (geNorm, NormFinder, BestKeeper and RefFinder). There was a small fluctuation in the cycle threshold (Ct) value and copy number of the pdp gene. Its expression stability was ranked in the vanguard of all algorithms and was the most suitable RG for quantification of expression by both qPCR and ddPCR of A. halolimnae under salt stress. Single RG pdp and RG combinations were used to normalize the expression of ectA, ectB, ectC and ectD under four salinities. The present study constitutes the first systematic analysis of endogenous RG selection for halophiles responding to salt stress. This work provides a valuable theory and an approach reference of internal control identification for ddPCR-based stress response models.


Assuntos
Algoritmos , Estresse Salino , Reação em Cadeia da Polimerase em Tempo Real , Estresse Salino/genética , Padrões de Referência , Perfilação da Expressão Gênica
8.
Nanomedicine ; 51: 102687, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37121458

RESUMO

Tumor-associated calcium signal transducer 2 (Trop2) is highly specific expressed in gastric carcinoma (GC). The combination of Trop2 antibody and phototherapy agents could exhibit synergetic antitumor activity. Black phosphorus nanosheets (BP) are covalently modified with Trop2 IgG antibodies via heterobifunctional linker of polyethylene glycol (PEG). Then the Trop2 antibody was directionally conjugated to BP via Schiff base reaction between aldehyde group from oxidized Trop2 antibody and amino group of PEG. The Trop2-functionalzied BP can significantly increase the endocytosis of BP in Trop2-positive GC cells exhibiting a reinforced antitumor activity under near infrared (NIR) irradiation. More importantly, a murine orthotopic GC model demonstrates that Trop2 antibody modification can significantly promote the accumulation of BP at tumor tissues and strengthen antitumoral activity of phototherapy. Directional conjugation of Trop2 antibody to BP facilitates the BP with superior stability, tumor targeting ability and excellent anti-tumor activity under NIR irradiation without systemic toxicity.


Assuntos
Carcinoma , Neoplasias Gástricas , Humanos , Animais , Camundongos , Fósforo , Fototerapia , Neoplasias Gástricas/terapia , Anticorpos , Linhagem Celular Tumoral
9.
Cell Tissue Res ; 388(1): 105-116, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35091805

RESUMO

Mesenchymal stem cells (MSCs) are considered a promising treatment for ischemic diseases, but their use is limited due to poor survival after injection. Hypoxia can significantly enhance the survival of MSCs. This study aimed to investigate hypoxia pretreatment of bone marrow mesenchymal stem cells (BM-MSCs) in hindlimb ischemia (HI) and the underlying mechanism. The HI mouse model was established and human BM-MSCs were injected into ischemic skeletal muscles. The blood flow reperfusion and capillary density were measured. In vitro, human BM-MSC cells were treated with hypoxia. The expression of NRG-1 and associated angiogenic factors were measured after knockdown or overexpression of NRG-1. The conditioned medium (CdM) of BM-MSCs was prepared and co-cultured with human umbilical vein endothelial cells (HUVECs), and then, the proliferation, migration, and angiogenesis of HUVECs were detected. After hypoxia pretreatment, NRG-1 expression, clone formation, proliferation, and angiogenic factor secretion from BM-MSCs were increased, while knockdown of NRG-1 reversed these results. In normoxia condition, overexpression of NRG-1 enhanced above factors. Additionally, hypoxia pretreatment of BM-MSCs induced the proliferation and migration of HUVECs and angiogenesis. Moreover, the injection of hypoxia pretreatment of BM-MSCs improved blood reperfusion and capillary density in HI mice, while knockdown of NRG-1 reversed the effect. Furthermore, the PI3K inhibitor and activator reversed the effect of NRG-1 overexpression and knockdown on angiogenesis. We concludes that hypoxia pretreatment of BM-MSCs facilitates angiogenesis and alleviates HI injury via NRG-1/PI3K/AKT pathway.


Assuntos
Hipóxia Celular , Isquemia , Transplante de Células-Tronco Mesenquimais , Neuregulina-1 , Animais , Células da Medula Óssea/metabolismo , Células Cultivadas , Membro Posterior , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Isquemia/terapia , Células-Tronco Mesenquimais/citologia , Camundongos , Neovascularização Fisiológica , Neuregulina-1/genética , Fosfatidilinositol 3-Quinases/metabolismo , Regulação para Cima
10.
Artigo em Inglês | MEDLINE | ID: mdl-35502996

RESUMO

A Gram-stain-positive, aerobic, endospore-forming and rod-shaped bacterium (KQ-3T), which grew at 10-45 °C (optimum 35 °C), pH 8.0-10.5 (optimum pH 9.0) and in the presence of 0-16 % (w/v) NaCl (optimum 3.0 %), was isolated from a soda lake and identified as representing a novel species using a polyphasic taxonomic approach. Strain KQ-3T was catalase-positive, oxidase-negative and non-motile. Phylogenetic analysis based on 16S rRNA gene sequence affiliated KQ-3T to the genus Alteribacter and showed the highest similarities to Alteribacter natronophilus M30T (97.90 %), Alteribacter aurantiacus K1-5T (97.84 %) and Alteribacter populi FJAT-45347T (97.22 %). Digital DNA-DNA hybridization and average nucleotide identity analyses revealed that KQ-3T displayed 21.4 and 72.81% genomic DNA relatedness with the most closely related strain, A. natronophilus M30T, respectively. KQ-3T contained all of the conserved signature indels that are specific for members of the genus Alteribacter. The DNA G+C content was 45.03 mol%. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the polar lipids consisted of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and one unidentified phospholipid. The predominant menaquinone was MK-7 (100%) and the major fatty acids (>10 %) comprised anteiso-C15 : 0, iso-C15 : 0 and iso-C16 : 0. Based on the data from the current polyphasic studies, KQ-3T represents a novel species of the genus Alteribacter, for which the name Alteribacter keqinensis sp. nov. is proposed. The type strain is KQ-3T (=ACCC 61799T=KCTC 33933T).


Assuntos
Bacillaceae , Lagos , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Lagos/microbiologia , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
J Mater Sci Mater Med ; 33(9): 62, 2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36057883

RESUMO

The purpose of this study is to investigate the role of Silibinin (SIL)-modified Hydroxyapatite coating on osseointegration in diabetes in vivo and in vitro and explore the mechanism of osteogenic differentiation of MC3T3-E1. RT-qPCR, Immunofluorescence, and Western blot were used to measure the expression level of oxidative Stress Indicators and osteogenic markers proteins. Moreover, CCK-8 assay was conducted to detect cell viability in hyperglycemia. Alizarin red staining and alkaline phosphatase staining were used to examine osteogenic function and calcium deposits. The diabetic rat model receive titanium rod implantation was set up successfully and Von-Gieson staining was used to examine femoral bone tissue around titanium rod. Our results showed that intracellular oxidative stress in hyperglycemia was overexpressed, while FoxO1, SIRT1, GPX1, and SOD2 were downregulated. SIL suppressed oxidative stress to promote osteogenic differentiation. Additionally, it was confirmed that SIL promoted osteogenic differentiation of MC3T3-E1 and obviously restored the osseointegration ability of diabetic rats. Further study indicated that SIL exerted its beneficial function through activation SIRT1/SOD2 signaling pathway to restore osteoblast function, and improved the osseointegration and stability of titanium rods in vivo. Our research suggested that the SIL-modulated oxidative Stress inhibition is responsible for the activation of the process of osteogenic differentiation through activation SIRT1/SOD2 signaling pathway in hyperglycemia, providing a novel insight into improving prosthetic osseointegration in diabetic patients. Hyperglycemia impaired the activity and function of MC3T3-E1 and inhibits bone formation by up-regulating intracellular ROS levels through inhibition of SIRT1/SOD2 signaling pathway. Local administrator SIL can improve the activity and function of osteoblasts and enhance osseointegration by reducing intracellular ROS through activation of SIRT1/SOD2 signaling pathway in DM rat models.


Assuntos
Diabetes Mellitus Experimental , Hiperglicemia , Animais , Diferenciação Celular , Durapatita , Osseointegração , Osteoblastos , Osteogênese , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Silibina , Sirtuína 1/metabolismo , Superóxido Dismutase/metabolismo , Titânio/farmacologia
12.
Biosci Biotechnol Biochem ; 85(4): 775-785, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33686395

RESUMO

This research aimed to evaluate the antihepatic fibrosis effect and explore the mechanism of Qiwei Qinggan Powder (QGS-7) in vivo and in vitro. Carbon tetrachloride (CCl4)-treated rats and hepatic stellate cells (HSCs) were used. QGS-7 treatment significantly improved the liver function of rats as indicated by decreased serum enzymatic activities of alanine aminotransferase, aspartate transaminase, and alkaline phosphatase. Meanwhile, the hydroxyproline of liver was significantly decreased. Histopathological results indicated that QGS-7 alleviated liver damage and reduced the formation of fibrosis septa. Moreover, QGS-7 significantly attenuated expressions of Alpha smooth muscle actin, Collagen I, Janus kinase 2 (JAK2), phosphorylation-JAK2, signal transducer and activator of transcription 3 (STAT3), phosphorylation-STAT3 in the rat hepatic fibrosis model. QGS-7 inhibited HSC proliferation and promoted it apoptosis. QGS-7 may affect hepatic fibrosis through JAK2/STAT3 signaling pathway so as to play an antihepatic fibrosis role.


Assuntos
Intoxicação por Tetracloreto de Carbono/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Medicina Tradicional da Mongólia , Animais , Intoxicação por Tetracloreto de Carbono/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Hidroxiprolina/metabolismo , Janus Quinase 2/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Testes de Função Hepática , Mongólia , Fosforilação , Pós , Ratos , Fator de Transcrição STAT3/metabolismo
13.
Biochem Biophys Res Commun ; 529(1): 35-42, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32560816

RESUMO

Postmenopausal osteoporosis (PMOP) is a frequent bone disorder responsible for an increased risk of disability to millions of individuals in the world. For identifying novel and effective targets to treat this disease, it is essential to explore the underlying molecular mechanisms. MicroRNAs (miRNAs) have been widely investigated due to their involvement in the pathophysiology of bone loss. In this study, we attempted to elucidate the role of miR-301-b in murine osteoclastogenesis. We found that miR-301-b expression was increased in the bone tissues from PMOP patients, along with up-regulated nuclear factor of activated T cells c1 (NFATC1), which were confirmed in ovariectomy (OVX)-induced mouse bone specimens and bone marrow-derived macrophages (BMMs). Osteoclastogenesis was found to be obviously suppressed by miR-301-b inhibitor, whereas being further promoted in BMMs transfected with miR-301-b mimic. The animal studies showed that osteoclastic miR-301-b knockout markedly up-regulated the bone mass by reducing osteoclastogenesis. Mechanistically, we found that cylindromatosis (CYLD) was a direct target of miR-301-b at the post-transcriptional level during osteoclastogenesis. The enhanced expression of CYLD led to a reduction of phosphorylated nuclear factor κB (NF-κB), along with remarkably decreased tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß). Finally, osteoclastic miR-301-b ablation evidently inhibited OVX-induced osteoclastogenesis, exhibiting protective effects against bone loss in rodent animals. Therefore, results in the study reported an important mechanism for osteoclastogenesis progression regulated by miR-301-b/CYLD/NF-κB pathway, which may be an effective therapeutic target for PMOP treatment.


Assuntos
MicroRNAs/genética , MicroRNAs/metabolismo , Osteoclastos/metabolismo , Osteoporose Pós-Menopausa/metabolismo , Animais , Enzima Desubiquitinante CYLD/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Osteogênese/genética , Osteogênese/fisiologia , Osteoporose Pós-Menopausa/genética , Osteoporose Pós-Menopausa/patologia , Ovariectomia/efeitos adversos , Transdução de Sinais
14.
J Org Chem ; 85(4): 2010-2018, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-31935325

RESUMO

A self-assembled G-quadruplex formed by guanosine and borate as the chiral scaffold was used to catalyze the asymmetric Friedel-Crafts reaction in water. Catalysis, depending on the self-assembly of guanosine and borate into a fibrillar structure in the presence of Cu2+ ions, can be modulated by the assembly concentration, temperature, and amount of Cu2+ ions. Detailed spectral experiments proved that the guanosine-based assembly in solution was responsible for the enantioselective catalysis, rather than small-molecule species. Some of the similar G-quartet assemblies were unable to promote the asymmetric reaction, implying unique properties of the current system, including excellent lifetime stability and supramolecular chiral structures. This work provided the first example of the self-assembled G-quadruplex achieving enantioselective catalysis and some perspective to better understand the design of nucleoside-based self-assemblies for an enantioselective reaction. In view of guanosine as a building block, these findings may be applied to discuss the prebiotic chiral catalyst preceded ribozymes.

15.
Antonie Van Leeuwenhoek ; 113(1): 127-136, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31506848

RESUMO

An alkaliphilic and moderately halophilic strain, designated YSP-3T, characterised by optimal growth at pH 9.0 and at 8.0% (w/v) NaCl, was isolated from Yangshapao Lake, Jilin Province, China. Cells of this strain is Gram-positive, straight rods and form a central or sub-terminal ellipsoidal endospore. Phylogenetic analysis based on 16S rRNA gene sequences indicated that it was grouped in the genus Bacillus with Bacillus aurantiacus K1-5T and Bacillus populi FJAT-45347T as the close relative (97.5 and 97.2% 16S rRNA gene sequence similarity, respectively). Genomic relatedness between strain YSP-3T and its close relative was evaluated using average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity with the values of 70.3-85.1%, 19.7-20.1% and 71.5-71.6%, respectively. Comparative genomics analysis showed that strain YSP-3T has distinct amino acid bias and significantly differences from foreign invasion events during evolution relative to the reference strains. Cell-wall peptidoglycan contains meso-diaminopimelic acid. The predominant polar lipids are phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol. The predominant quinone is menaquinone-7. The major fatty acids of strain YSP-3T are anteiso-C15:0, iso-C15:0, iso-C16:0, anteiso-C17:0 and Iso-C14:0. DNA G + C content of strain YSP-3T is 48.3 mol%. Based on genomics analysis, physiological, biochemical and chemotaxonomic data, strain YSP-3T represent a novel species, for which the name Bacillus lacisalsi sp. nov. is proposed. The type strain is YSP-3T (  = ACCC 60365T = KCTC 33934T).


Assuntos
Bacillus/genética , Lagos/microbiologia , Composição de Bases/genética , Genômica , Filogenia , RNA Ribossômico 16S/genética
16.
Antonie Van Leeuwenhoek ; 112(6): 897-903, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30788630

RESUMO

A novel Gram-stain positive, short rod, forming sub-terminal endospores of ellipsoidal shape, halophilic, alkaliphilic and aerobic bacterium, designated strain KQ-12T, was isolated from a saline-alkaline lake in China, and characterised by a polyphasic taxonomic approach. The isolate grew at 4-40 °C (optimum, 25 °C), at pH 8.0-10.0 (pH 9.0) and in the presence of 0-16% (w/v) NaCl (8%). 16S rRNA gene sequence similarity of KQ-12T to species in the genera Salipaludibacillus ranged from 96.6 to 98.1%. Phylogenetic trees indicated that the strain should be assigned to the genus Salipaludibacillus. The polar lipids of KQ-12T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and an unidentified phospholipid and its major cellular fatty acids were anteiso-C15:0, anteiso-C17:0, iso-C15:0, and C16:0. The isoprenoid quinone was MK-7. These key chemotaxonomic properties also confirmed the affiliation of the strain to the genus Salipaludibacillus. However, some physiological, biochemical properties, low average nucleotide identity and low digital DNA-DNA hybridization relatedness values enabled the strain to be differentiated from closely related species of the genus Salipaludibacillus. Thus, KQ-12T can be classified as a novel species in the genus Salipaludibacillus, for which the name Salipaludibacillus keqinensis sp. nov. is proposed. The type strain is KQ-12T ( =  ACCC 60430T   =  KCTC 33935T).


Assuntos
Bacillaceae/isolamento & purificação , Lagos/microbiologia , Bacillaceae/classificação , Bacillaceae/genética , Bacillaceae/metabolismo , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Lagos/análise , Filogenia , RNA Ribossômico 16S/genética , Cloreto de Sódio/análise , Cloreto de Sódio/metabolismo
17.
Oral Dis ; 25(6): 1581-1588, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31009146

RESUMO

OBJECTIVES: Mitophagy is an important mitochondrial quality control mechanism. In this study, we investigated the mitochondrial damage and mitophagy occurred in inflammatory human dental pulp and lipopolysaccharide-stimulated preodontoblasts. MATERIALS AND METHODS: In dental pulp tissues and lipopolysaccharide-stimulated preodontoblasts, immunofluorescences and Western blot were performed to detect the expression of mitochondrial and mitophagy-related proteins, and autophagy markers were also examined. Reactive oxygen species generated by mitochondria were examined by MitoSOX. Transmission electron microscope (TEM) was used to examine the morphology of mitochondria in lipopolysaccharide-stimulated preodontoblasts. RESULTS: The active fission activity of mitochondria and mitophagy in inflammatory dental pulp was observed. In lipopolysaccharide-treated preodontoblasts, mitophagy-related proteins were also upregulated. Moreover, increased reactive oxygen species in the inflamed preodontoblasts were observed. Additionally, single-membrane autolysosomes containing partially degraded mitochondria with swollen inner membranes in lipopolysaccharide-treated preodontoblasts were observed by TEM. CONCLUSIONS: These results indicate that mitochondria were damaged and mitophagy might be activated to degrade impaired mitochondria in inflamed odontoblasts.


Assuntos
Dilatação Mitocondrial , Mitofagia/genética , Odontoblastos , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo
18.
J Microencapsul ; 36(8): 728-737, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31544561

RESUMO

Objective: To synthesise HSA-RB-DOX nanoparticles, measure its characteristics and preliminarily evaluate its anti-cancer effects.Methods: Doxorubicin (DOX) and Rose Bengal (RB) were co-delivered using albumin as a carrier. HSA-RB-DOX nanoparticles were prepared by RB-induced self-assembly of albumin. Its characteristics were measured and anti-cancer effects were tested in MCF-7 cells and tumour-bearing mice.Results: HSA-RB-DOX nanoparticle with a mean size of 42 nm was stable in different medium and behaved controlled release characteristic. It was well took in MCF-7 cells and inhibited MCF-7 cells proliferation by inducing reactive oxygen species (ROS) production. It retained a much higher blood concentration up to 12 h and accumulated more in tumour tissues. In tumour-bearing mice, HSA-RB-DOX nanoparticles inhibited tumour growth and even decreased its volume from 100 to 50 mm3, with barely no influence on body weight.Conclusions: HSA-RB-DOX nanoparticles may be potentially used for enhanced treatment of breast cancer.


Assuntos
Albuminas/química , Antineoplásicos/uso terapêutico , Neoplasias da Mama/terapia , Doxorrubicina/administração & dosagem , Nanopartículas/química , Rosa Bengala/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Int J Syst Evol Microbiol ; 68(7): 2271-2278, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29851375

RESUMO

A Gram-stain-negative, motile and rod-shaped bacterium, designated strain B2T, which can synthesize purple pigments of violacein and dexyoviolacein, was isolated from Tianshan glacier in Xinjiang, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that it was grouped in the genus Massilia with Massilia glaciei B448-2T, Massilia eurypsychrophila B528-3T and Massilia psychrophila B1555-1T as its closest relatives (98.2, 97.9 and 97.0 % 16S rRNA gene sequence similarity, respectively). Genomic relatedness between strain B2T and its closest relatives was evaluated using average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity, with values of 77.93-85.08 %, 22.4-23.4 % and 71.54-72.99 %, respectively. Q-8 was the major ubiquinone. The major fatty acids (>5 %) of strain B2T were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C12 : 0 and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The major polar lipids included phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content of strain B2T was 63.51 mol%. Based on genomic relatedness, physiological, biochemical and chemotaxonomic data, strain B2T (=CGMCC 1.6993T=DSM 19531T=KCTC 32446T) is considered to represent a novel species within the genus Massilia, for which the name Massilia violaceinigra sp. nov. is proposed.


Assuntos
Camada de Gelo/microbiologia , Oxalobacteraceae/classificação , Pergelissolo/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oxalobacteraceae/genética , Oxalobacteraceae/isolamento & purificação , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
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