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1.
Front Med (Lausanne) ; 7: 516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33015091

RESUMO

Lupus nephritis represents a common and serious complication of the autoimmune disease Systemic Lupus Erythematosus (SLE). Clinical studies suggest that several proteins related to iron metabolism, including transferrin, serve as urinary biomarkers of lupus nephritis. We previously reported that in female NZBWF1 mice, a commonly used mouse model of SLE with a female sex bias, increased urinary transferrin excretion and renal iron accumulation occur around the onset of albuminuria. The current study investigated whether similar findings occur in male mice of a different mouse model of SLE, the MRL/lpr mouse. Two different cohorts were studied: MRL/lpr mice at an early, pre-albuminuric age (8 weeks), and after developing albuminuria (>100 mg/dL, confirmed by ELISA); age-matched MRL/MpJ control strain mice served for comparison. Urinary transferrin excretion was dramatically increased in the older, albuminuric MRL/lpr mice compared to the age-matched MRL/MpJ (P < 0.05), but there was no significant difference between strains at 8 weeks of age. Similarly, there were no significant differences between strains in renal cortical or outer medullary non-heme iron concentrations at 8 weeks. In the older, albuminuric MRL/lpr mice, renal cortical and outer medullary non-heme iron concentrations were significantly increased compared with age-matched MRL/MpJ mice, as was the expression of the iron storage protein ferritin (P < 0.01). Together, these data show that increased urinary transferrin excretion and renal tissue iron accumulation also occurs in albuminuric male MRL/lpr mice, suggesting that renal iron accumulation may be a feature of multiple mouse models of SLE.

2.
Metabolomics ; 16(10): 106, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33021695

RESUMO

INTRODUCTION: Approximately 1% of the world's population is impacted by epilepsy, a chronic neurological disorder characterized by seizures. One-third of epileptic patients are resistant to AEDs, or have medically refractory epilepsy (MRE). One non-invasive treatment that exists for MRE includes the ketogenic diet, a high-fat, low-carbohydrate diet. Despite the KD's success in seizure attenuation, it has a few risks and its mechanisms remain poorly understood. The KD has been shown to improve metabolism and mitochondrial function in epileptic phenotypes. Potassium channels have implications in epileptic conditions as they have dual roles as metabolic sensors and control neuronal excitation. OBJECTIVES: The goal of this study was to explore changes in the lipidome in hippocampal and cortical tissue from Kv1.1-KO model of epilepsy. METHODS: FT-ICR/MS analysis was utilized to examine nonpolar metabolome of cortical and hippocampal tissue isolated from a Kv1.1 channel knockout mouse model of epilepsy (n = 5) and wild-type mice (n = 5). RESULTS: Distinct metabolic profiles were observed, significant (p < 0.05) features in hippocampus often being upregulated (FC ≥ 2) and the cortex being downregulated (FC ≤ 0.5). Pathway enrichment analysis shows lipid biosynthesis was affected. Partition ratio analysis revealed that the ratio of most metabolites tended to be increased in Kv1.1-/-. Metabolites in hippocampal tissue were commonly upregulated, suggesting seizure initiation in the hippocampus. Aberrant mitochondrial function is implicated by the upregulation of cardiolipin, a common component in the mitochondrial membrane. CONCLUSION: Generally, our study finds that the lipidome is changed in the hippocampus and cortex in response to Kv1.1-KO indicating changes in membrane structural integrity and synaptic transmission.


Assuntos
Epilepsia/metabolismo , Metabolismo dos Lipídeos/fisiologia , Animais , Dieta Cetogênica/métodos , Modelos Animais de Doenças , Epilepsia/dietoterapia , Hipocampo/metabolismo , Canal de Potássio Kv1.1/genética , Canal de Potássio Kv1.1/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout
3.
J Proteomics ; 223: 103812, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32418907

RESUMO

Epilepsy is a disorder that affects around 1% of the population. Approximately one third of patients do not respond to anti-convulsant drugs treatment. To understand the underlying biological processes involved in drug resistant epilepsy (DRE), a combination of proteomics strategies was used to compare molecular differences and enzymatic activities in tissue implicated in seizure onset to tissue with no abnormal activity within patients. Label free quantitation identified 17 proteins with altered abundance in the seizure onset zone as compared to tissue with normal activity. Assessment of oxidative protein damage by protein carbonylation identified additional 11 proteins with potentially altered function in the seizure onset zone. Pathway analysis revealed that most of the affected proteins are involved in energy metabolism and redox balance. Further, enzymatic assays showed significantly decreased activity of transketolase indicating a disruption of the Pentose Phosphate Pathway and diversion of intermediates into purine metabolic pathway, resulting in the generation of the potentially pro-convulsant metabolites. Altogether, these findings suggest that imbalance in energy metabolism and redox balance, pathways critical to proper neuronal function, play important roles in neuronal network hyperexcitability and can be used as a primary target for potential therapeutic strategies to combat DRE. SIGNIFICANCE: Epileptic seizures are some of the most difficult to treat neurological disorders. Up to 40% of patients with epilepsy are resistant to first- and second-line anticonvulsant therapy, a condition that has been classified as refractory epilepsy. One potential therapy for this patient population is the ketogenic diet (KD), which has been proven effective against multiple refractory seizure types However, compliance with the KD is extremely difficult, and carries severe risks, including ketoacidosis, renal failure, and dangerous electrolyte imbalances. Therefore, identification of pathways disruptions or shortages can potentially uncover cellular targets for anticonvulsants, leading to a personalized treatment approach depending on a patient's individual metabolic signature.


Assuntos
Epilepsia , Convulsões , Anticonvulsivantes/uso terapêutico , Metabolismo Energético , Epilepsia/tratamento farmacológico , Humanos , Oxirredução , Convulsões/tratamento farmacológico
4.
Plant Physiol ; 181(3): 1029-1049, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31501300

RESUMO

Microalgae accumulate lipids during stress such as that of nutrient deprivation, concomitant with cessation of growth and depletion of chloroplasts. By contrast, certain small chemical compounds selected by high-throughput screening in Chlamydomonas reinhardtii can induce lipid accumulation during growth, maintaining biomass. Comprehensive pathway analyses using proteomics, transcriptomics, and metabolomics data were acquired from Chlamydomonas cells grown in the presence of one of two structurally distinct lipid activators. WD10784 stimulates both starch and lipid accumulation, whereas WD30030-treated cells accumulate only lipids. The differences in starch accumulation are largely due to differential effects of the two compounds on substrate levels that feed into starch synthesis and on genes encoding starch metabolic enzymes. The compounds had differential effects on photosynthesis, respiration, and oxidative stress pathways. Cells treated with WD10784 showed slowed growth over time and reduced abundance of photosynthetic proteins, decreased respiration, and increased oxidative stress proteins, glutathione, and reactive oxygen species specific to this compound. Both compounds maintained central carbon and nitrogen metabolism, including the tricarboxylic acid cycle, glycolysis, respiration, and the Calvin-Benson-Bassham cycle. There were few changes in proteins and transcripts related to fatty acid biosynthesis, whereas proteins and transcripts for triglyceride production were elevated, suggesting that lipid synthesis is largely driven by substrate availability. This study reports that the compound WD30030 and, to a lesser extent WD10784, increases lipid and lipid droplet synthesis and storage without restricting growth or biomass accumulation by mechanisms that are substantially different from nutrient deprivation.


Assuntos
Chlamydomonas/metabolismo , Compostos Orgânicos/farmacologia , Chlamydomonas/efeitos dos fármacos , Ciclo do Ácido Cítrico/efeitos dos fármacos , Glicólise/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/fisiologia , Metabolômica , Fotossíntese/efeitos dos fármacos , Fotossíntese/fisiologia , Proteômica/métodos , Amido/metabolismo
5.
J Biol Chem ; 294(19): 7821-7832, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-30918025

RESUMO

Archaea are a distinct and deeply rooted lineage that harbor eukaryotic-like mechanisms, including several that manage chromosome function. In previous work, the thermoacidophilic crenarchaeon, Sulfolobus solfataricus, was subjected to adaptive laboratory evolution to produce three strains, called SARC, with a new heritable trait of super acid resistance. These strains acquired heritable conserved transcriptomes, yet one strain contained no mutations. Homologous recombination without allele replacement at SARC acid resistance genes caused changes in both phenotype and expression of the targeted gene. As recombination displaces chromatin proteins, their involvement was predicted in the SARC trait. Native chromatin proteins are basic and highly abundant and undergo post-translational modification through lysine monomethylation. In this work, their modification states were investigated. In all SARC lines, two chromatin proteins, Cren7 and Sso7d, were consistently undermethylated, whereas other chromatin proteins were unaltered. This pattern was heritable in the absence of selection and independent of transient exposure to acid stress. The bulk of Sso7d was undermethylated at three contiguous N-terminal lysine residues but not at central or C-terminal regions. The N-terminal region formed a solvent-exposed patch located on the opposite side of the binding domain associated with the DNA minor groove. By analogy to eukaryotic histones, this patch could interact with other chromosomal proteins and be modulated by differential post-translational modification. Previous work established an epigenetic-like mechanism of adaptation and inheritance in S. solfataricus The identification of heritable epigenetic marks in this work further supports the occurrence of an epigenetic process in archaea.


Assuntos
Proteínas Arqueais , Proteínas de Ligação a DNA , Evolução Molecular Direcionada , Epigênese Genética , Regulação da Expressão Gênica em Archaea , Locos de Características Quantitativas , Sulfolobus solfataricus , Adaptação Fisiológica , Proteínas Arqueais/química , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Domínios Proteicos , Processamento de Proteína Pós-Traducional , Sulfolobus solfataricus/química , Sulfolobus solfataricus/genética , Sulfolobus solfataricus/metabolismo , Transcriptoma
6.
J Cereb Blood Flow Metab ; 39(5): 849-858, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29125372

RESUMO

The mechanistic role of arterial shear stress in the regulation of cerebrovascular responses to physiological stimuli (exercise and hypercapnia) is poorly understood. We hypothesised that, if shear stress is a key regulator of arterial dilation, then matched increases in shear, induced by distinct physiological stimuli, would trigger similar dilation of the large extra-cranial arteries. Participants ( n = 10) participated in three 30-min experimental interventions, each separated by ≥48 h: (1) mild-hypercapnia (FICO2:∼0.045); (2) submaximal cycling (EX; 60%HRreserve); or (3) resting (time-matched control, CTRL). Blood flow, diameter, and shear rate were assessed (via Duplex ultrasound) in the internal carotid and vertebral arteries (ICA, VA) at baseline, during and following the interventions. Hypercapnia and EX produced similar elevations in blood flow and shear rate through the ICA and VA ( p < 0.001), which were both greater than CTRL. Vasodilation of ICA and VA diameter in response to hypercapnia (5.3 ± 0.8 and 4.4 ± 2.0%) and EX (4.7 ± 0.7 and 4.7 ± 2.2%) were similar, and greater than CTRL ( p < 0.001). Our findings indicate that matched levels of shear, irrespective of their driving stimulus, induce similar extra-cranial artery dilation. We demonstrate, for the first time in humans, an important mechanistic role for the endothelium in regulating cerebrovascular response to common physiological stimuli in vivo.


Assuntos
Artéria Carótida Interna/fisiologia , Artérias Cerebrais/fisiologia , Vasodilatação , Artéria Vertebral/fisiologia , Adulto , Velocidade do Fluxo Sanguíneo , Dióxido de Carbono/metabolismo , Artéria Carótida Interna/fisiopatologia , Artérias Cerebrais/fisiopatologia , Circulação Cerebrovascular , Exercício Físico , Humanos , Hipercapnia/metabolismo , Hipercapnia/fisiopatologia , Masculino , Estresse Mecânico , Artéria Vertebral/fisiopatologia , Adulto Jovem
7.
Meat Sci ; 148: 64-71, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30317011

RESUMO

The objective of this study was to evaluate the association between oxidative damage to proteins (represented by protein carbonylation) and beef tenderness. Three experimental groups were selected by shear force (SF): tender (38.2 ±â€¯2.9 N), intermediate (51.9 ±â€¯6.8 N), and tough meat (74.5 ±â€¯7.8 N). Two-dimensional electrophoresis with hydrazide fluorophore derivatization was used. The structural proteins actin (ACTA1), myosin (MYL1 and MYL3), desmin (DES) and troponin T (TNNT1 and TNNT3), antioxidant proteins (PRDX1, PRDX2 and PARK7) and heat shock proteins (HSPB1, CRYAB and HSPB6) showed an increase in the oxidative damage in tender meat when compared to the intermediate and tough meat (P < .05). Decrease in oxidative damage of the metabolic enzymes (TPI1, GAPDH and ENO3) were observed in tender meat group (P < .05). The present results suggest that oxidation act on the proteins of different metabolic pathways and consequently affect meat tenderness in Angus crossbred cattle.


Assuntos
Proteínas Musculares/química , Proteômica/métodos , Carne Vermelha/análise , Animais , Bovinos , Masculino , Músculo Esquelético/química , Estresse Oxidativo , Resistência ao Cisalhamento
8.
J Nutr ; 148(12): 1886-1894, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30517726

RESUMO

Background: Humans and mice absorb bovine milk exosomes and their RNA cargos. Objectives: The objectives of this study were to determine whether milk exosome- and RNA-depleted (ERD) and exosome- and RNA-sufficient (ERS) diets alter the concentrations of purine metabolites in mouse livers, and to determine whether diets depleted of bovine milk alter the plasma concentration and urine excretion of purine metabolites in adults and infants, respectively. Methods: C57BL/6 mice were fed ERD (providing 2% of the microRNA cargos compared with ERS) and ERS diets starting at age 3 wk; livers were collected at age 7 wk. Plasma and 24-h urine samples were collected from healthy adults who consumed (DCs) or avoided (DAs) dairy products. Spot urine samples were collected from healthy infants fed human milk (HM), milk formula (MF), or soy formula (SF) at age 3 mo. Purine metabolites were analyzed in liver, plasma, and urine; mRNAs and microRNAs were analyzed in the livers of female mice. Results: We found that 9 hepatic purine metabolites in ERD-fed mice were 1.76 ± 0.43 times the concentrations in ERS-fed mice (P < 0.05). Plasma concentrations and urine excretion of purine metabolites in DAs was ≤1.62 ± 0.45 times the concentrations in DCs (P < 0.05). The excretion of 13 purine metabolites in urine from SF infants was ≤175 ± 39 times the excretion in HM and MF infants (P < 0.05). mRNA expression of 5'-nucleotidase, cytosolic IIIB, and adenosine deaminase in mice fed ERD was 0.64 ± 0.52 and 0.60 ± 0.28 times the expression in mice fed ERS, respectively. Conclusion: Diets depleted of bovine-milk exosomes and RNA cargos caused increases in hepatic purine metabolites in mice, and in plasma and urine from human adults and infants, compared with exosome-sufficient controls. These findings are important, because purines play a role in intermediary metabolism and cell signaling.


Assuntos
Exossomos/fisiologia , Fígado/metabolismo , MicroRNAs/fisiologia , Leite/química , Purinas/metabolismo , Animais , Bovinos , Dieta , Humanos , Camundongos , Camundongos Endogâmicos C57BL , RNA , Transcriptoma
9.
PLoS One ; 13(12): e0207161, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30540769

RESUMO

The success of Staphylococcus aureus as a pathogen is due in part to its ability to adapt to changing environmental conditions using signal transduction pathways, such as metabolite- responsive regulators and two-component systems. S. aureus has a two-component system encoded by the gene pair sav0224 (hptS) and sav0223 (hptR) that regulate the hexose phosphate transport (uhpT) system in response to extracellular glucose-6-phosphate. Glycolytic intermediates such as glucose-6-phosphate are important carbon sources that also modulate the activity of the global metabolite-responsive transcriptional regulator CcpA. Because uhpT has a putative CcpA binding site in its promoter and it is regulated by HptR, it was hypothesized the regulons of CcpA and HptR might intersect. To determine if the regulatory domains of CcpA and HptRS overlap, ccpA was deleted in strains SA564 and SA564-ΔhptRS and growth, metabolic, proteomic, and transcriptional differences were assessed. As expected, CcpA represses hptS and hptR in a glucose dependent manner; however, upon CcpA derepression, the HptRS system functions as a transcriptional activator of metabolic genes within the CcpA regulon. Importantly, inactivation of ccpA and hptRS altered sensitivity to fosfomycin and ampicillin in the absence of exogenous glucose-6-phosphate, indicating that both CcpA and HptRS modulate antibiotic susceptibility.


Assuntos
Proteínas de Bactérias/genética , Staphylococcus aureus/metabolismo , Amônia/análise , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cromatografia Líquida de Alta Pressão , Fosfomicina/farmacologia , Glucose/análise , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Mutagênese , Regiões Promotoras Genéticas , Proteoma/análise , Proteômica , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimento , Transcrição Gênica/efeitos dos fármacos
10.
Geobiology ; 16(6): 659-673, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30019522

RESUMO

Microbes belonging to the genus Metallosphaera oxidize sulfidic minerals. These organisms thrive at temperature extremes and are members of the archaeal phylum Crenarchaeota. Because they can employ a lithoautotrophic metabolism, energy availability likely limits their activity raising questions about how they conduct biogeochemical activity. Vesicles are membrane encapsulated structures produced by all biological lineages but using very different mechanisms. Across the Crenarchaeota, it has been proposed that a eukaryotic-like Endosomal Sorting Complex Required for Transport system promotes formation of these structures but in response to unknown signals and for undefined purposes. To address such questions, Metallosphaera sedula vesicle formation and function were studied under lithoautotrophic conditions. Energy deprivation was evaluated and found to stimulate vesicle synthesis while energy excess repressed vesicle formation. Purified vesicles adhered rapidly to the primary copper ore, chalcopyrite, and formed compact monolayers. These vesicle monolayers catalyzed iron oxidation and solubilization of mineralized copper in a time-dependent process. As these activities were membrane associated, their potential transfer by vesicle fusion to M. sedula cells was examined. Fluorophore-loaded vesicles rapidly transferred fluorescence under environmentally relevant conditions. Vesicles from a related archaeal species were also capable of fusion; however, this process was species-specific as vesicles from different species were incapable of fusion. In addition, vesicles produced by a copper-resistant M. sedula cell line transferred copper extrusion capacity along with improved viability over mutant M. sedula cells lacking copper transport proteins. Membrane vesicles may therefore play a role in modulating energy-related traits in geochemical environments by fusion-mediated protein delivery.


Assuntos
Archaea/metabolismo , Archaea/fisiologia , Proteínas Arqueais/metabolismo
11.
J Nutr Biochem ; 59: 123-128, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29986306

RESUMO

Exosomes are nanoparticles that transfer cargos from donor cells to recipient cells where they elicit changes in gene expression and metabolism. Evidence suggests that exosomes and their cargos are also absorbed from dietary sources such as bovine milk, and bovine exosomes promote the growth of myofibers in murine C2C12 myotube cell cultures. The aim of the current study was to determine whether the dietary intake of bovine milk exosomes alters strength, gene expression and amino acid profiles in murine skeletal muscles. Male and female C57BL/6 mice, age three weeks, were fed an AIN93G-based, exosome and RNA-depleted (ERD) diet for six weeks; controls were fed an exosome and RNA-sufficient (ERS) diet. Variables of feeding behavior, metabolism, grip strength, liver and kidney function, amino acid profiles, and gene expression patterns were analyzed by using metabolic cages, grip strength analyzers, clinical chemistry analyzers, targeted LC/MS-MS, and RNA sequencing analysis. The diets had no effect on food and water intake, respiratory exchange rate, physical activity, grip strength, markers of liver and kidney dysfunction, and amino acid profiles in muscle. Only twelve and nine mRNAs were differentially expressed in skeletal muscle from female and male mice, respectively, fed ERD and ERS diets. The modest effect of the ERD diet on gene expression and levels of free amino acids in skeletal muscle is consistent with observations that bovine milk exosomes and their cargos accumulate in tissues other than skeletal muscle.


Assuntos
Exossomos/genética , Leite/química , Músculo Esquelético/efeitos dos fármacos , RNA/farmacologia , Aminoácidos/metabolismo , Animais , Dieta , Ingestão de Alimentos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/fisiologia , Fígado/efeitos dos fármacos , Fígado/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Condicionamento Físico Animal
12.
Neurobiol Dis ; 114: 45-52, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29409952

RESUMO

OBJECTIVE: Adenosine participates in maintaining the excitatory/inhibitory balance in neuronal circuits. Studies indicate that adenosine levels in the cortex and hippocampus increase and exert sleep pressure in sleep-deprived and control animals, whereas in epilepsy reduced adenosine tone promotes hyperexcitability. To date, the role of adenosine in pathological conditions that result in both seizures and sleep disorders is unknown. Here, we determined adenosine tone in sleep and seizure regulating brain regions of Kv1.1 knockout (KO) mice, a model of temporal epilepsy with comorbid sleep disorders. METHODS: 1) Reverse phase-high performance liquid chromatography (RP-HPLC) was performed on brain tissue to determine levels of adenosine and adenine nucleotides. 2) Multi-electrode array extracellular electrophysiology was used to determine adenosine tone in the hippocampal CA1 region and the lateral hypothalamus (LH). RESULTS: RP-HPLC indicated a non-significant decrease in adenosine (~50%, p = 0.23) in whole brain homogenates of KO mice. Regional examination of relative levels of adenine nucleotides indicated decreased ATP and increased AMP in the cortex and hippocampus and increased adenosine in cortical tissue. Using electrophysiological and pharmacological techniques, estimated adenosine levels were ~35% lower in the KO hippocampal CA1 region, and 1-2 fold higher in the KO LH. Moreover, the increased adenosine in KO LH contributed to lower spontaneous firing rates of putative wake-promoting orexin/hypocretin neurons. INTERPRETATION: This is the first study to demonstrate a direct correlation of regionally distinct dichotomous adenosine levels in a single model with both epilepsy and comorbid sleep disorders. The weaker inhibitory tone in the dorsal hippocampus is consistent with lower seizure threshold, whereas increased adenosine in the LH is consistent with chronic partial sleep deprivation. This work furthers our understanding of how adenosine may contribute to pathological conditions that underlie sleep disorders within the epileptic brain.


Assuntos
Adenosina/metabolismo , Modelos Animais de Doenças , Epilepsia/metabolismo , Epilepsia/fisiopatologia , Transtornos do Sono-Vigília/metabolismo , Transtornos do Sono-Vigília/fisiopatologia , Animais , Comorbidade , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Knockout , Técnicas de Cultura de Órgãos
13.
Redox Biol ; 12: 139-149, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28236766

RESUMO

The World Health Organization designates lidocaine as an essential medicine in healthcare, greatly increasing the probability of human exposure. Its use has been associated with ROS generation and neurotoxicity. Physiological and metabolomic alterations, and genetics leading to the clinically observed adverse effects have not been temporally characterized. To study alterations that may lead to these undesirable effects, Saccharomyces cerevisiae grown on aerobic carbon sources to stationary phase was assessed over 6h. Exposure of an LC50 dose of lidocaine, increased mitochondrial depolarization and ROS/RNS generation assessed using JC-1, ROS/RNS specific probes, and FACS. Intracellular calcium also increased, assessed by ICP-MS. Measurement of the relative ATP and ADP concentrations indicates an initial 3-fold depletion of ATP suggesting an alteration in the ATP:ADP ratio. At the 6h time point the lidocaine exposed population contained ATP concentrations roughly 85% that of the negative control suggesting the surviving population adapted its metabolic pathways to, at least partially restore cellular bioenergetics. Metabolite analysis indicates an increase of intermediates in the pentose phosphate pathway, the preparatory phase of glycolysis, and NADPH. Oxidative stress produced by lidocaine exposure targets aconitase decreasing its activity with an observed decrease in isocitrate and an increase citrate. Similarly, increases in α-ketoglutarate, malate, and oxaloacetate imply activation of anaplerotic reactions. Antioxidant molecule glutathione and its precursor amino acids, cysteine and glutamate were greatly increased at later time points. Phosphatidylserine externalization suggestive of early phase apoptosis was also observed. Genetic studies using metacaspase null strains showed resistance to lidocaine induced cell death. These data suggest lidocaine induces perpetual mitochondrial depolarization, ROS/RNS generation along with increased glutathione to combat the oxidative cellular environment, glycolytic to PPP cycling of carbon generating NADPH, obstruction of carbon flow through the TCA cycle, decreased ATP generation, and metacaspase dependent apoptotic cell death.


Assuntos
Anestésicos Locais/efeitos adversos , Lidocaína/efeitos adversos , Metabolômica/métodos , Saccharomyces cerevisiae/efeitos dos fármacos , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Metabolismo Energético/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Espectrometria de Massas em Tandem
14.
Int J Biol Macromol ; 96: 817-832, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28057574

RESUMO

Proteins play crucial roles in biological systems, thus studies comparing the protein pattern present in a healthy sample with an affected sample have been widely used for disease biomarker discovery. Although proteins containing metal ions constitute only a small proportion of the proteome, they are essential in a multitude of structural and functional processes. The correct association between metal ions and proteins is essential because this binding can significantly interfere with normal protein function. Employment of a metalloproteomic study of liver samples from diabetic rats permitted determination of the differential abundance of copper-, selenium-, zinc- and magnesium-associated proteins between diabetic, diabetic treatment with insulin and non-diabetic rats. Proteins were detected by ESI-MS/MS. Seventy-five different proteins were found with alterations in the metal ions of interest. The most prominent pathways affected under the diabetic model included: amino-acid metabolism and its derivates, glycogen storage, metabolism of carbohydrates, redox systems and glucose metabolism. Overall, the current methods employed yielded a greater understanding of metal binding and how type 1 diabetes and insulin treatment can modify some metal bonds in proteins, and therefore affect their mechanism of action and function.


Assuntos
Diabetes Mellitus/metabolismo , Fígado/metabolismo , Metaloproteínas/metabolismo , Metais/metabolismo , Proteômica , Aminoácidos/metabolismo , Animais , Metabolismo dos Carboidratos , Metabolismo Energético , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar
15.
OMICS ; 20(12): 711-726, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27849439

RESUMO

Diabetes mellitus type 1 (DM1) is a major public health problem that continues to burden the healthcare systems worldwide, costing exponentially more as the epidemic grows. Innovative strategies and omics system diagnostics for earlier diagnosis or prognostication of DM1 are essential to prevent secondary complications and alleviate the associated economic burden. In a preclinical study design that involved streptozotocin (STZ)-induced DM1, insulin-treated STZ-induced DM1, and control rats, we characterized the insulin-dependent and -independent changes in protein profiles in liver samples. Digested proteins were subjected to LC-MSE for proteomic data. Progenesis QI data processing and analysis of variance were utilized for statistical analyses. We found 305 proteins with significantly altered abundance among the control, DM1, and insulin-treated DM1 groups (p < 0.05). These differentially regulated proteins were related to enzymes that function in key metabolic pathways and stress responses. For example, gluconeogenesis appeared to return to control levels in the DM1 group after insulin treatment, with the restoration of gluconeogenesis regulatory enzyme, FBP1. Insulin administration to DM1 rats also restored the blood glucose levels and enzymes of general stress and antioxidant response systems. These observations are crucial for insights on DM1 pathophysiology and new molecular targets for future clinical biomarkers, drug discovery, and development. Additionally, we underscore that proteomics offers much potential in preclinical biomarker discovery for diabetes as well as common complex diseases such as cancer, dementia, and infectious disorders.


Assuntos
Insulina/metabolismo , Fígado/metabolismo , Medicina de Precisão/métodos , Proteoma/metabolismo , Animais , Biomarcadores/metabolismo , Biologia Computacional , Masculino , Proteômica , Ratos
16.
Proteomics ; 16(13): 1889-903, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27193513

RESUMO

Clinical usage of lidocaine, a pro-oxidant has been linked with severe, mostly neurological complications. The mechanism(s) causing these complications is independent of the blockade of voltage-gated sodium channels. The budding yeast Saccharomyces cerevisiae lacks voltage-gated sodium channels, thus provides an ideal system to investigate lidocaine-induced protein and pathway alterations. Whole-proteome alterations leading to these complications have not been identified. To address this, S. cerevisiae was grown to stationary phase and exposed to an LC50 dose of lidocaine. The differential proteomes of lidocaine treatment and control were resolved 6 h post exposure using 2D DIGE. Amine reactive dyes and carbonyl reactive dyes were used to assess protein abundance and protein oxidation, respectively. Quantitative analysis of these dyes (⩾ 1.5-fold alteration, p ⩽ 0.05) revealed a total of 33 proteoforms identified by MS differing in abundance and/or oxidation upon lidocaine exposure. Network analysis showed enrichment of apoptotic proteins and cell wall maintenance proteins, while the abundance of proteins central to carbohydrate metabolism, such as triosephosphate isomerase and glyceraldehyde-3-phosphate dehydrogenase, and redox proteins superoxide dismutase and peroxiredoxin were significantly decreased. Enzymes of carbohydrate metabolism, such as phosphoglycerate kinase and enolase, the TCA cycle enzyme aconitase, and multiple ATP synthase subunits were found to be oxidatively modified. Also, the activity of aconitase was found to be decreased. Overall, these data suggest that toxic doses of lidocaine induce significant disruption of glycolytic pathways, energy production, and redox balance, potentially leading to cell malfunction and death.


Assuntos
Anestésicos Locais/efeitos adversos , Lidocaína/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Eletroforese em Gel Diferencial Bidimensional/métodos , Metabolismo dos Carboidratos/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Proteoma/metabolismo , Proteômica , Saccharomyces cerevisiae/metabolismo
17.
Plant Physiol ; 169(2): 1371-81, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26282239

RESUMO

Glutathione (GSH) is essential for many aspects of plant biology and is associated with jasmonate signaling in stress responses. We characterized an Arabidopsis (Arabidopsis thaliana) jasmonate-hypersensitive mutant (jah2) with seedling root growth 100-fold more sensitive to inhibition by the hormone jasmonyl-isoleucine than the wild type. Genetic mapping and genome sequencing determined that the mutation is in intron 6 of GLUTATHIONE SYNTHETASE2, encoding the enzyme that converts γ-glutamylcysteine (γ-EC) to GSH. The level of GSH in jah2 was 71% of the wild type, while the phytoalexin-deficient2-1 (pad2-1) mutant, defective in GSH1 and having only 27% of wild-type GSH level, was not jasmonate hypersensitive. Growth defects for jah2, but not pad2, were also seen in plants grown to maturity. Surprisingly, all phenotypes in the jah2 pad2-1 double mutant were weaker than in jah2. Quantification of γ-EC indicated these defects result from hyperaccumulation of this GSH precursor by 294- and 65-fold in jah2 and the double mutant, respectively. γ-EC reportedly partially substitutes for loss of GSH, but growth inhibition seen here was likely not due to an excess of total glutathione plus γ-EC because their sum in jah2 pad2-1 was only 16% greater than in the wild type. Further, the jah2 phenotypes were lost in a jasmonic acid biosynthesis mutant background, indicating the effect of γ-EC is mediated through jasmonate signaling and not as a direct result of perturbed redox status.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Dipeptídeos/metabolismo , Mutação , Oxilipinas/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Oxilipinas/farmacologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
18.
Nat Cell Biol ; 14(6): 614-24, 2012 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-22561345

RESUMO

Kinetochores attach the replicated chromosomes to the mitotic spindle and orchestrate their transmission to the daughter cells. Kinetochore-spindle binding and chromosome segregation are mediated by the multi-copy KNL1(Spc105), MIS12(Mtw1) and NDC80(Ndc80) complexes that form the so-called KMN network. KMN-spindle attachment is regulated by the Aurora B(Ipl1) and MPS1(Mps1) kinases. It is unclear whether other mechanisms exist that support KMN activity during the cell cycle. Using budding yeast, we show that kinetochore protein Cnn1 localizes to the base of the Ndc80 complex and promotes a functionally competent configuration of the KMN network. Cnn1 regulates KMN activity in a spatiotemporal manner by inhibiting the interaction between its complexes. Cnn1 activity peaks in anaphase and is driven by the Cdc28, Mps1 and Ipl1 kinases.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Cinetocoros/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Anáfase , Proteínas de Ciclo Celular/genética , Cromossomos Fúngicos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Fuso Acromático/metabolismo
19.
Sports Health ; 1(1): 21-30, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23015851

RESUMO

BACKGROUND: Recent research showed 82% of 233 retired National Football League players under age 50 had abnormal narrowing and blockages in arteries compared to the general population of the same age. It has been suggested that early screening and intervention in this at-risk population be a priority. HYPOTHESIS: Omega-3 essential fatty acid has been shown to improve cardiovascular lipid risk factors and should improve lipid profiles in professional football players to help reduce their recently shown accelerated risk of developing cardiovascular disease. METHODS: A total of 36 active national football players were randomly assigned to 2 groups: the first group (n = 20) was provided fish oil capsules (2200 mg of mixed docosahexaenoic acid and eicosapentaenoic acid and 360 mg of other omega-3s), and the second group (n = 16) served as controls during a 60-day trial. Vertical Auto Profile cholesterol tests directly measuring serum low-density lipoprotein, high-density lipoprotein, and other subfractions were performed. Compliance, side effects, and seafood consumption data were also collected. Baseline, midpoint, and poststudy blood work measured plasma docosahexaenoic acid and eicosapentaenoic acid. RESULTS: Treatment increased high-density lipoprotein (average percent change: +25.96, control +14.16), decreased triglycerides treatment (-8.06, control +43.98), very low-density lipoprotein treatment (-13.98, control +23.18), intermediate density lipoprotein (-27.58, control +12.07), remnant lipoproteins (-23.86, control +8.33), and very low-density lipoprotein-3 (-17.10, control +7.77). An average increase of 106.67% for docosahexaenoic acid and 365.82% for eicosapentaenoic acid compared to control was also shown. CONCLUSION: Omega-3 supplementation significantly improved the lipid profile of active players randomized to treatment. These results suggest that fish oil supplementation is an effective way to increase eicosapentaenoic acid and docosahexaenoic acid levels in plasma and should be considered as a method to improve modifiable cardiovascular risk lipid factors in professional football players. CLINICAL RELEVANCE: A prospective study examining the effects of 60 days of a highly purified fish oil supplementation in professional football players.

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