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1.
Microb Cell Fact ; 23(1): 88, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38519954

RESUMO

BACKGROUND: The halophilic bacterium Halomonas elongata is an industrially important strain for ectoine production, with high value and intense research focus. While existing studies primarily delve into the adaptive mechanisms of this bacterium under fixed salt concentrations, there is a notable dearth of attention regarding its response to fluctuating saline environments. Consequently, the stress response of H. elongata to salt shock remains inadequately understood. RESULTS: This study investigated the stress response mechanism of H. elongata when exposed to NaCl shock at short- and long-time scales. Results showed that NaCl shock induced two major stresses, namely osmotic stress and oxidative stress. In response to the former, within the cell's tolerable range (1-8% NaCl shock), H. elongata urgently balanced the surging osmotic pressure by uptaking sodium and potassium ions and augmenting intracellular amino acid pools, particularly glutamate and glutamine. However, ectoine content started to increase until 20 min post-shock, rapidly becoming the dominant osmoprotectant, and reaching the maximum productivity (1450 ± 99 mg/L/h). Transcriptomic data also confirmed the delayed response in ectoine biosynthesis, and we speculate that this might be attributed to an intracellular energy crisis caused by NaCl shock. In response to oxidative stress, transcription factor cysB was significantly upregulated, positively regulating the sulfur metabolism and cysteine biosynthesis. Furthermore, the upregulation of the crucial peroxidase gene (HELO_RS18165) and the simultaneous enhancement of peroxidase (POD) and catalase (CAT) activities collectively constitute the antioxidant defense in H. elongata following shock. When exceeding the tolerance threshold of H. elongata (1-13% NaCl shock), the sustained compromised energy status, resulting from the pronounced inhibition of the respiratory chain and ATP synthase, may be a crucial factor leading to the stagnation of both cell growth and ectoine biosynthesis. CONCLUSIONS: This study conducted a comprehensive analysis of H. elongata's stress response to NaCl shock at multiple scales. It extends the understanding of stress response of halophilic bacteria to NaCl shock and provides promising theoretical insights to guide future improvements in optimizing industrial ectoine production.


Assuntos
Diamino Aminoácidos , Halomonas , Cloreto de Sódio/farmacologia , Cloreto de Sódio/metabolismo , Halomonas/genética , Halomonas/metabolismo , Pressão Osmótica , Perfilação da Expressão Gênica , Peroxidases/metabolismo
2.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396963

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder with a prolonged prodromal phase. Higher urinary bis(monoacylglycerol)phosphate (BMP) levels associate with LRRK2 (leucine-rich repeat kinase 2) and GBA1 (glucocerebrosidase) mutations, and are considered as potential noninvasive biomarkers for predicting those mutations and PD progression. However, their reliability has been questioned, with inadequately investigated genetics, cohorts, and population. In this study, multiple statistical hypothesis tests were employed on urinary BMP levels and sequences of 90 PD-risk single nucleotide polymorphisms (SNPs) from Parkinson's Progression Markers Institution (PPMI) participants. Those SNPs were categorized into four groups based on their impact on BMP levels in various cohorts. Variants rs34637584 G/A and rs34637584 A/A (LRRK2 G2019S) were identified as the most relevant on increasing urinary BMP levels in the PD cohort. Meanwhile, rs76763715 T/T (GBA1) was the primary factor elevating BMP levels in the prodromal cohort compared to its T/C and C/C variants (N370S) and the PD cohort. Proteomics analysis indicated the changed transport pathways may be the reasons for elevated BMP levels in prodromal patients. Our findings demonstrated that higher urinary BMP levels alone were not reliable biomarkers for PD progression or gene mutations but might serve as supplementary indicators for early diagnosis and treatment.


Assuntos
Lisofosfolipídeos , Monoglicerídeos , Doença de Parkinson , Humanos , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes , Mutação , Biomarcadores
3.
Appl Microbiol Biotechnol ; 107(17): 5351-5365, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37421474

RESUMO

Ectoine is generally produced by the fermentation process of Halomonas elongata DSM 2581 T, which is one of the primary industrial ectoine production techniques. To effectively monitor and control the fermentation process, the important parameters require accurate real-time measurement. However, for ectoine fermentation, three critical parameters (cell optical density, glucose, and product concentration) cannot be measured conveniently in real-time due to time variation, strong coupling, and other constraints. As a result, our work effectively created a series of hybrid models to predict the values of these three parameters incorporating both fermentation kinetics and machine learning approaches. Compared with the traditional machine learning models, our models solve the problem of insufficient data which is common in fermentation. In addition, a simple kinetic modeling is only applicable to specific physical conditions, so different physical conditions require refitting the function, which is tedious to operate. However, our models also overcome this limitation. In this work, we compared different hybrid models based on 5 feature engineering methods, 11 machine-learning approaches, and 2 kinetic models. The best models for predicting three key parameters, respectively, are as follows: CORR-Ensemble (R2: 0.983 ± 0.0, RMSE: 0.086 ± 0.0, MAE: 0.07 ± 0.0), SBE-Ensemble (R2: 0.972 ± 0.0, RMSE: 0.127 ± 0.0, MAE: 0.078 ± 0.0), and SBE-Ensemble (R2:0.98 ± 0.0, RMSE: 0.023 ± 0.001, MAE: 0.018 ± 0.001). To verify the universality and stability of constructed models, we have done an experimental verification, and its results showed that our proposed models have excellent performance. KEY POINTS: • Using the kinetic models for producing simulated data • Through different feature engineering methods for dimension reduction • Creating a series of hybrid models to predict the values of three parameters in the fermentation process of Halomonas elongata DSM 2581 T.


Assuntos
Diamino Aminoácidos , Halomonas , Halomonas/genética , Halomonas/metabolismo , Fermentação
4.
Anal Chem ; 94(33): 11659-11669, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35942642

RESUMO

The "design-build-test-learn" (DBTL) cycle has been adopted in rational high-throughput screening to obtain high-yield industrial strains. However, the mismatch between build and test slows the DBTL cycle due to the lack of high-throughput analytical technologies. In this study, a highly efficient, accurate, and noninvasive detection method of gentamicin (GM) was developed, which can provide timely feedback for the high-throughput screening of high-yield strains. First, a self-made tool was established to obtain data sets in 24-well plates based on the color of the cells. Subsequently, the random forest (RF) algorithm was found to have the highest prediction accuracy with an R2 value of 0.98430 for the same batch. Finally, a stable genetically high-yield strain (998 U/mL) was successfully screened out from 3005 mutants, which was verified to improve the titer by 72.7% in a 5 L bioreactor. Moreover, the verified new data sets were updated on the model database in order to improve the learning ability of the DBTL cycle.


Assuntos
Gentamicinas , Ensaios de Triagem em Larga Escala , Reatores Biológicos , Computadores , Aprendizado de Máquina
5.
Biotechnol Bioeng ; 119(12): 3509-3525, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36062959

RESUMO

The halophilic bacterium Halomonas elongata DSM 2581T generally adapts well to high level of salinity by biosynthesizing ectoine, which functions as an important compatible solute protecting the cell against external salinity environment. Halophilic bacteria have specific metabolic activities under high-salt conditions and are gradually applied in various industries. The present study focuses on investigating the physiological and metabolic mechanism of H. elongata DSM 2581T driven by the external salinity environment. The physiological metabolic dynamics under salt stress were investigated to evaluate the effect of NaCl stress on the metabolism of H. elongata. The obtained results demonstrated that ectoine biosynthesis transited from a nongrowth-related process to a growth-related process when the NaCl concentration varied from 1% to 13% (w/v). The maximum biomass (Xm = 41.37 g/L), and highest ectoine production (Pm = 12.91 g/L) were achieved under 8% NaCl. Moreover, the maximum biomass (Xm ) and the maximum specific growth rates (µm ) showed a first rising and then declining trend with the increased NaCl stress. Furthermore, the transcriptome analysis of H. elongata under different NaCl concentrations demonstrated that both 8% and 13% NaCl conditions resulted in increased expressions of genes involved in the pentose phosphate pathway, Entner-Doudoroff pathway, flagellar assembly pathway, and ectoine metabolism, but negatively affected the tricarboxylic acid cycle and fatty acid metabolism. At last, the proposed possible adaptation mechanism under the optimum NaCl concentration in H. elongata was described.


Assuntos
Halomonas , Cloreto de Sódio/metabolismo
6.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563289

RESUMO

Genetic mutations of trappc9 cause intellectual disability with the atrophy of brain structures and variable obesity by poorly understood mechanisms. Trappc9-deficient mice develop phenotypes resembling pathological changes in humans and appear overweight shortly after weaning, and thus are useful for studying the pathogenesis of obesity. Here, we investigated the effects of trappc9 deficiency on the proliferation and differentiation capacity of adipose-derived stem cells (ASCs). We isolated ASCs from mice before overweight was developed and found that trappc9-null ASCs exhibited signs of premature senescence and cell death. While the lineage commitment was retained, trappc9-null ASCs preferred adipogenic differentiation. We observed a profound accumulation of lipid droplets in adipogenic cells derived from trappc9-deficient ASCs and marked differences in the distribution patterns and levels of calcium deposited in osteoblasts obtained from trappc9-null ASCs. Biochemical studies revealed that trappc9 deficiency resulted in an upregulated expression of rab1, rab11, and rab18, and agitated autophagy in ASCs. Moreover, we found that the content of neural stem cells in both the subventricular zone of the lateral ventricle and the subgranular zone of the dentate gyrus vastly declined in trappc9-null mice. Collectively, our results suggest that obesity, as well as brain structure hypoplasia induced by the deficiency of trappc9, involves an impairment in the plasticity of stem cells.


Assuntos
Sobrepeso , Células-Tronco , Adipogenia/genética , Tecido Adiposo/metabolismo , Animais , Diferenciação Celular/genética , Proliferação de Células , Células Cultivadas , Camundongos , Obesidade/metabolismo , Sobrepeso/metabolismo , Células-Tronco/metabolismo
7.
Biotechnol Bioeng ; 118(10): 4092-4104, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34255354

RESUMO

The rapid, accurate and noninvasive detection of biomass and plant cell browning can provide timely feedback on cell growth in plant cell culture. In this study, Siraitia grosvenorii suspension cells were taken as an example, a phenotype analysis platform was successfully developed to predict the biomass and the degree of cell browning based on the color changes of cells in computer-aided vision technology. First, a self-made laboratory system was established to obtain images. Then, matrices were prepared from digital images by a self-developed high-throughput image processing tool. Finally, classification models were used to judge different cell types, and then a semi-supervised classification to predict different degrees of cell browning. Meanwhile, regression models were developed to predict the plant cell mass. All models were verified with a good agreement by biological experiments. Therefore, this method can be applied for low-cost biomass estimation and browning degree quantification in plant cell culture.


Assuntos
Técnicas de Cultura de Células , Cucurbitaceae/citologia , Cucurbitaceae/metabolismo , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Células Vegetais/metabolismo
8.
Mol Ther ; 28(9): 2083-2095, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32526202

RESUMO

Transcription growth factor ß (TGF-ß) signaling-triggered epithelial-to-mesenchymal transition (EMT) process is associated with tumor stemness, metastasis, and chemotherapy resistance. However, the epigenomic basis for TGF-ß-induced EMT remains largely unknown. Here we reveal that HDAC1-mediated global histone deacetylation and the gain of specific histone H3 lysine 27 acetylation (H3K27ac)-marked enhancers are essential for the TGF-ß-induced EMT process. Enhancers gained upon TGF-ß treatment are linked to gene activation of EMT markers and cancer metastasis. Notably, dynamic enhancer gain or loss mainly occurs within pre-existing topologically associated domains (TADs) in epithelial cells, with minimal three-dimensional (3D) genome architecture reorganization. Through motif enrichment analysis of enhancers that are lost or gained upon TGF-ß stimulation, we identify FOXA2 as a key factor to activate epithelial-specific enhancer activity, and we also find that TEAD4 forms a complex with SMAD2/3 to mediate TGF-ß signaling-triggered mesenchymal enhancer reprogramming. Together, our results implicate that key transcription-factor (TF)-mediated enhancer reprogramming modulates the developmental transition in TGF-ß signaling-associated cancer metastasis.


Assuntos
Reprogramação Celular/efeitos dos fármacos , Elementos Facilitadores Genéticos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Células A549 , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Fator 3-beta Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Histona Desacetilase 1/metabolismo , Histonas/metabolismo , Humanos , Camundongos , Proteínas Musculares/metabolismo , Metástase Neoplásica , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/metabolismo , Ativação Transcricional/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo
9.
Anal Chem ; 91(21): 13582-13590, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31603309

RESUMO

Acetohydroxyacid synthase (AHAS) exists in plants and many microorganisms (including gut flora) but not in mammals, making it an attractive drug target. Fluorescent-based methods should be practical for high-throughput screening of inhibitors. Herein, we describe the development of the first AHAS fluorogenic assay based on an intramolecular charge transfer (ICT)-based fluorescent probe. The assay is facile, sensitive, and continuous and can be applied toward various AHASs from different species, AHAS mutants, and crude cell lysates. The fluorogenic assay was successfully applied for (1) high-throughput screening of commerical herbicides toward different AHASs for choosing matching herbicides, (2) identification of a Soybean AHAS gene with broad-spectrum herbicide resistance, and (3) identification of selective inhibitors toward intestinal-bacterial AHASs. Among the AHAS inhibitors, an active agent was found for selective inhibition of obesity-associated Ruminococcus torques growth, implying the possibility of AHAS inhibitors for the ultimate goal toward antiobesity therapeutics. The fluorogenic assay opens the door for high-throughput programs in AHAS-related fields, and the design principle might be applied for development of fluorogenic assays of other synthases.


Assuntos
Acetolactato Sintase/análise , Corantes Fluorescentes/química , Acetolactato Sintase/antagonistas & inibidores , Acetolactato Sintase/genética , Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Microbioma Gastrointestinal , Resistência a Herbicidas/genética , Ensaios de Triagem em Larga Escala , Humanos
10.
Prep Biochem Biotechnol ; 48(2): 188-193, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29355461

RESUMO

Pyruvate oxidase (PyOD) is a very powerful enzyme for clinical diagnostic applications and environmental monitoring. Influences of temperature on cell growth, plasmid stability, and PyOD expression during the PyOD fermentation process by recombinant Escherichia coli were investigated. Based on the influences of temperature on the physiological metabolism, a novel high-cell density fed-batch cultivation with gradient temperature decrease strategy for effective PyOD production was achieved, under which the biomass (OD600) of recombinant E. coli could reach to 71 and the highest PyOD activity in broth could reach to 3,307 U/L in 26 hr fermentation.


Assuntos
Aerococcus/enzimologia , Técnicas de Cultura Celular por Lotes/métodos , Escherichia coli/metabolismo , Piruvato Oxidase/metabolismo , Aerococcus/genética , Aerococcus/metabolismo , Reatores Biológicos , Meios de Cultura/metabolismo , Escherichia coli/genética , Fermentação , Plasmídeos/genética , Plasmídeos/metabolismo , Piruvato Oxidase/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura
11.
J Pharmacol Sci ; 132(1): 92-99, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27671351

RESUMO

Recently, anandamide (AEA) analogues have been well recognized for its potent neuroprotective effects in counteracting the deterioration of Alzheimer's disease (AD) brains through multiple pathological processes. In our previous studies, dipotassium N-stearoyltyrosinate (NSTK), an AEA analogue synthesized by our laboratory was reported to exert significant efficacy through multiple interventions. Within this study, the amyloid precursor protein (APP)SWE/presenilin-1 (PS1)M146V/TauP301L mouse (3×Tg-AD) model was used to explore further the neuroprotective effects of NSTK and its underlying mechanisms. NSTK could increase spontaneous locomotor activity in the open field and low anxiety-like behavior in the elevated plus maze, and improve the spatial memory deficits in the Morris water maze. The biochemical analysis suggested that NSTK could decrease Aß42 deposition, abnormal tau aggregation, and the expressions of p-APP Thr668, PS1 and p-tau Ser202/Thr205 in the hippocampus of 3×Tg-AD mice. Consistently, NSTK could reduce the level of malondialdehyde, increase the activity of superoxide dismutase and catalase. Up-regulation of Bcl-2, and down-regulation of BAX, caspase-3 and inflammatory cytokines also occurred in the hippocampus of 3×Tg-AD mice after treatment with NSTK. Thus, NSTK could intervene in multiple pathological processes of AD and would be a drug candidate against AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Tirosina/análogos & derivados , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Caspase 3/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fármacos Neuroprotetores/farmacologia , Presenilina-1/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Tirosina/farmacologia , Tirosina/uso terapêutico , Proteína X Associada a bcl-2/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo
12.
Cell Mol Neurobiol ; 35(3): 425-432, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25452160

RESUMO

Abeta accumulation, a hallmark of Alzheimer's disease, promotes the disease progress in multiple facets. Abeta is formed through amyloidogenic cleavage pathway of amyloid precursor protein (APP). Production of Abeta can be decreased via activation of 5-HT2C receptor, which enhances alternative APP non-amyloidogenic cleavage. Besides, as one of the best characterized Aß degrading enzymes, neprilysin (NEP) in AD progress has drawn more and more attention. We investigated whether there exists any connection between 5-HT2C receptor and NEP expression. The mRNA and protein expressions of NEP were increased after treatment of 5-HT2C receptor agonist RO-60-0175 in concentration- and time-dependent manners, and NEP expression was decreased after treatment of 5-HT2C receptor antagonist SB242084 correspondingly. These results suggest that 5-HT2C receptor may inhibit the Abeta formation by promoting NEP expression. The underlying mechanism will be explored in follow-up study and may provide potential target for AD therapy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Neprilisina/biossíntese , Receptor 5-HT2C de Serotonina/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia
13.
Bioprocess Biosyst Eng ; 38(5): 917-28, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25552347

RESUMO

The fungal morphology during submerged cultivations has a profound influence on the overall performance of bioreactors. In this research, glucoamylase production by Aspergillus niger has been taken as a model to improve more insights. The morphology engineering could be conducted effectively by changing the seed morphology, as well as specific power input. During the fed-batch cultivations, pellet formation under milder shear stress field helped to reduce the broth viscosity, thus relieving oxygen limitation and promoting the enzyme production. Furthermore, we found that the relation between the shear stress field, which was characterized by energy dissipation rate/circulation function (EDCF), and enzyme activity was consistent with quadratic parabola, which threw light on the process optimization and scale-up for industrial enzyme production.


Assuntos
Aspergillus niger/enzimologia , Reatores Biológicos , Microbiologia Industrial , Biomassa , Enzimas/química , Fermentação , Glucana 1,4-alfa-Glucosidase/biossíntese , Cinética , Oxigênio/química , Engenharia de Proteínas , Reologia , Resistência ao Cisalhamento , Estresse Mecânico , Viscosidade
14.
Cell Mol Neurobiol ; 34(3): 369-78, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24363090

RESUMO

Tau truncation is widely detected in Alzheimer's disease brain. Caspases activation is suggested to play a significant role in tau truncation at Aspartate 421 (D421) according to their ability to cleave recombinant tau in vitro. Ample evidence has shown that caspase-6 is involved in cognitive impairment and expressed in AD brain. Reactive oxygen species (ROS) can lead to caspase-6 activation and correlate with AD. Here, we transfected human embryonic kidney 293 (HEK 293) cells with Tau 441 plasmid and investigated the role of caspase-6 and caspase-3 in ROS-mediated tau truncation. Our data demonstrated that H2O2 induced oxidative stress and increased tau truncation. Caspase-6 and caspase-3 activity also increased in a dose-dependent manner in HEK 293/Tau cells during H2O2 insult. When cells were treated with an ROS inhibitor N-acetyl-L-cysteine, tau truncation was significantly suppressed. Compared with H2O2 (100 µM)/non-inhibitor group or single-inhibitor groups (z-VEID-fmk, caspase-6 inhibitor or z-DEVD-fmk, and caspase-3 inhibitor), tau truncation induced by H2O2 was effectively reduced in the combinative inhibitors group. Similar results were shown when cells were transfected with specific caspase-3 and caspase-6 siRNA. Inhibition of caspase-6 led to decline of caspase-3 activation. Taken together, our results suggest that the combination of caspase-6 and caspase-3 aggravates tau truncation at D421 induced by H2O2. Caspase-6 may play an important part in activating caspase-3. Further investigation of how the synergic role of caspase-6 and caspase-3 affects tau truncation may provide new visions for potential AD therapies.


Assuntos
Ácido Aspártico/metabolismo , Caspase 3/fisiologia , Caspase 6/fisiologia , Proteínas tau/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Células HEK293 , Humanos
15.
Cell Mol Neurobiol ; 34(3): 409-17, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24414340

RESUMO

Alzheimer's disease (AD) is characterized by deposition of beta-amyloid peptides (Aß) and progressive loss of neurons. Neural stem/progenitor cells (NSPCs) can proliferate and produce immature neurons even in the brain of AD patients. However, Aß42 significantly decreased the expression of RhoC in NSPCs during the co-incubation (P < 0.01). Treating with RhoC siRNA prevented membrane from protrusion and led to a significant reduction in cell migration in responses to SDF-1. Compared with wild-type mice, the numbers of RhoC-immunoreactive cells in hippocampus and cortex were significantly down-regulated in APP/PS1 mice aged 9 months. The results suggest that Aß42 down-regulates the expression of RhoC in NSPCs in vitro and in vivo; down-regulated RhoC expression results in decreased migration of NSPCs.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Movimento Celular/fisiologia , Células-Tronco Neurais/fisiologia , Fragmentos de Peptídeos/toxicidade , Proteínas ras/biossíntese , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Neurais/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Proteínas ras/farmacologia , Proteína de Ligação a GTP rhoC
16.
J Hazard Mater ; 468: 133485, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38377898

RESUMO

Biodegradation is an efficient and cost-effective approach to remove residual penicillin G sodium (PGNa) from the environment. In this study, the effective PGNa-degrading strain SQW1 (Sphingobacterium sp.) was screened from contaminated soil using enrichment technique. The effects of critical operational parameters on PGNa degradation by strain SQW1 were systematically investigated, and these parameters were optimized by response surface methodology to maximize PGNa degradation. Comparative experiments found the extracellular enzyme to completely degrade PGNa within 60 min. Combined with whole genome sequencing of strain SQW1 and LC-MS analysis of degradation products, penicillin acylase and ß-lactamase were identified as critical enzymes for PGNa biodegradation. Moreover, three degradation pathways were postulated, including ß-lactam hydrolysis, penicillin acylase hydrolysis, decarboxylation, desulfurization, demethylation, oxidative dehydrogenation, hydroxyl reduction, and demethylation reactions. The toxicity of PGNa biodegradation intermediates was assessed using paper diffusion method, ECOSAR, and TEST software, which showed that the biodegradation products had low toxicity. This study is the first to describe PGNa-degrading bacteria and detailed degradation mechanisms, which will provide new insights into the PGNa biodegradation.


Assuntos
Penicilina Amidase , Sphingobacterium , Sphingobacterium/genética , Sphingobacterium/metabolismo , Penicilina Amidase/metabolismo , Penicilina G , Biodegradação Ambiental
17.
JCI Insight ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38889014

RESUMO

Loss-of-function mutations of the gene encoding the trafficking protein particle complex subunit 9 (trappc9) cause autosomal recessive intellectual disability and obesity by unknown mechanisms. Genome-wide analysis links trappc9 to non-alcoholic fatty liver disease (NAFLD). Trappc9-deficient mice have been shown to appear overweight shortly after weaning. Here, we analyzed serum biochemistry and histology of adipose and liver tissues to determine the incidence of obesity and NAFLD in trappc9-deficient mice and combined transcriptomic and proteomic analyses, pharmacological studies, and biochemical and histological examinations of postmortem mouse brains to unveil mechanisms involved. We found that trappc9-deficient mice presented with systemic glucose homeostatic disturbance, obesity and NAFLD, which were relieved upon chronic treatment combining dopamine receptor D2 (DRD2) agonist quinpirole and DRD1 antagonist SCH23390. Blood glucose homeostasis in trappc9-deficient mice was restored upon administrating quinpirole alone. RNA-sequencing analysis of DRD2-containing neurons and proteomic study of brain synaptosomes revealed signs of impaired neurotransmitter secretion in trappc9-deficient mice. Biochemical and histological studies of mouse brains showed that trappc9-deficient mice synthesized dopamine normally, but their dopamine-secreting neurons had a lower abundance of structures for releasing dopamine in the striatum. Our study suggests that trappc9 loss-of-function causes obesity and NAFLD by constraining dopamine synapse formation.

18.
Cancer Cell ; 42(1): 135-156.e17, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38101410

RESUMO

Comprehensive molecular analyses of metastatic hepatocellular carcinoma (HCC) are lacking. Here, we generate multi-omic profiling of 257 primary and 176 metastatic regions from 182 HCC patients. Primary tumors rich in hypoxia signatures facilitated polyclonal dissemination. Genomic divergence between primary and metastatic HCC is high, and early dissemination is prevalent. The remarkable neoantigen intratumor heterogeneity observed in metastases is associated with decreased T cell reactivity, resulting from disruptions to neoantigen presentation. We identify somatic copy number alterations as highly selected events driving metastasis. Subclones without Wnt mutations show a stronger selective advantage for metastasis than those with Wnt mutations and are characterized by a microenvironment rich in activated fibroblasts favoring a pro-metastatic phenotype. Finally, metastases without Wnt mutations exhibit higher enrichment of immunosuppressive B cells that mediate terminal exhaustion of CD8+ T cells via HLA-E:CD94-NKG2A checkpoint axis. Collectively, our results provide a multi-dimensional dissection of the complex evolutionary process of metastasis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Linfócitos T CD8-Positivos/patologia , Multiômica , Mutação , Microambiente Tumoral/genética
19.
Appl Environ Microbiol ; 79(9): 2922-31, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23435886

RESUMO

Haloferax mediterranei is able to accumulate the bioplastic poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with more than 10 mol% 3-hydroxyvalerate (3HV) from unrelated carbon sources. However, the pathways that produce propionyl coenzyme A (propionyl-CoA), an important precursor of 3HV monomer, have not yet been determined. Bioinformatic analysis of H. mediterranei genome indicated that this strain uses multiple pathways for propionyl-CoA biosynthesis, including the citramalate/2-oxobutyrate pathway, the aspartate/2-oxobutyrate pathway, the methylmalonyl-CoA pathway, and a novel 3-hydroxypropionate pathway. Cofeeding of pathway intermediates and inactivating pathway-specific genes supported that these four pathways were indeed involved in the biosynthesis of 3HV monomer. The novel 3-hydroxypropionate pathway that couples CO2 assimilation with PHBV biosynthesis was further confirmed by analysis of (13)C positional enrichment in 3HV. Notably, (13)C metabolic flux analysis showed that the citramalate/2-oxobutyrate pathway (53.0% flux) and the 3-hydroxypropionate pathway (30.6% flux) were the two main generators of propionyl-CoA from glucose. In addition, genetic perturbation on the transcriptome of the ΔphaEC mutant (deficient in PHBV accumulation) revealed that a considerable number of genes in the four propionyl-CoA synthetic pathways were significantly downregulated. We determined for the first time four propionyl-CoA-supplying pathways for PHBV production in haloarchaea, particularly including a new 3-hydroxypropionate pathway. These results would provide novel strategies for the production of PHBV with controllable 3HV molar fraction.


Assuntos
Acil Coenzima A/metabolismo , Genoma Arqueal/genética , Haloferax mediterranei/enzimologia , Ácidos Pentanoicos/metabolismo , Poliésteres/metabolismo , Acil Coenzima A/genética , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Vias Biossintéticas , Ciclo do Carbono , Dióxido de Carbono/metabolismo , Isótopos de Carbono/análise , Biologia Computacional , Regulação para Baixo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica em Archaea , Técnicas de Inativação de Genes , Glucose/metabolismo , Haloferax mediterranei/química , Haloferax mediterranei/genética , Espectroscopia de Ressonância Magnética , Análise de Sequência com Séries de Oligonucleotídeos , Poliésteres/química , Análise de Sequência de Proteína , Deleção de Sequência
20.
Cell Mol Neurobiol ; 33(8): 1149-57, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24057433

RESUMO

Neural stem/progenitor cells (NSPCs) of the subgranular zone have been implicated in cognitive processes, which represent a potentially important source of regenerative medicine for the treatment of neurodegenerative diseases such as Alzheimer's disease (AD). In our previous studies, ZY-1, a novel nicotinic analog, improved cognitive function in transgenic mice model of AD. However, the effect of ZY-1 on the NSPCs remains unclear. Here, we show that ZY-1 significantly increased proliferation and migration of NSPCs, but failed to affect NSPCs differentiation in vitro. Furthermore, during the proliferative period, ZY-1 enhanced intracellular reactive oxygen species (ROS) levels. Meanwhile, ZY-1 also inhibited the levels of Aß42-induced ROS. Our data indicate that ZY-1 regulates adult hippocampal neurogenesis in vitro, at least partly due to modulating intracellular ROS levels. These results, taken together with those of our previous studies, suggest that ZY-1 might have a potential therapeutic effect for the treatment of AD.


Assuntos
Células-Tronco Adultas/citologia , Movimento Celular/efeitos dos fármacos , Hipocampo/citologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Nicotina/análogos & derivados , Células-Tronco Adultas/efeitos dos fármacos , Células-Tronco Adultas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Separação Celular , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Nicotina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Receptores Nicotínicos/metabolismo
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