ABSTRACT
Hsaio and colleagues link gut microbes to autism spectrum disorders (ASD) in a mouse model. They show that ASD symptoms are triggered by compositional and structural shifts of microbes and associated metabolites, but symptoms are relieved by a Bacteroides fragilis probiotic. Thus probiotics may provide therapeutic strategies for neurodevelopmental disorders.
Subject(s)
Child Development Disorders, Pervasive/microbiology , Gastrointestinal Tract/microbiology , Animals , Female , HumansABSTRACT
The oral microbiome is linked to oral and systemic health, but its fluctuation under frequent daily activities remains elusive. Here, we sampled saliva at 10- to 60-min intervals to track the high-resolution microbiome dynamics during the course of human activities. This dense time series data showed that eating activity markedly perturbed the salivary microbiota, with tongue-specific Campylobacter concisus and Oribacterium sinus and dental plaque-specific Lautropia mirabilis, Rothia aeria, and Neisseria oralis increased after every meal in a temporal order. The observation was reproducible in multiple subjects and across an 11-mo period. The microbiome composition showed significant diurnal oscillation patterns at different taxonomy levels with Prevotella/Alloprevotella increased at night and Bergeyella HMT 206/Haemophilus slowly increased during the daytime. We also identified microbial co-occurring patterns in saliva that are associated with the intricate biogeography of the oral microbiome. Microbial source tracking analysis showed that the contributions of distinct oral niches to the salivary microbiome were dynamically affected by daily activities, reflecting the role of saliva in exchanging microbes with other oral sites. Collectively, our study provides insights into the temporal microbiome variation in saliva and highlights the need to consider daily activities and diurnal factors in design of oral microbiome studies.
Subject(s)
Microbiota , Saliva , Humans , Prevotella , RNA, Ribosomal, 16S , Saliva/microbiologyABSTRACT
The composition of tick microbiomes varies both within and among tick species. Whether this variation is intrinsic (related to tick characteristics) or extrinsic (related to vertebrate host and habitat) is poorly understood but important, as microbiota can influence the reproductive success and vector competence of ticks. We aimed to uncover what intrinsic and extrinsic factors best explain the microbial composition and taxon richness of 11 species of neotropical ticks collected from eight species of small mammals in 18 forest fragments across central Panama. Microbial richness varied among tick species, life stages, and collection sites but was not related to host blood source. Microbiome composition was best explained by tick life stage, with bacterial assemblages of larvae being a subset of those of nymphs. Collection site explained most of the bacterial taxa with differential abundance across intrinsic and extrinsic factors. Francisella and Rickettsia were highly prevalent, but their proportional abundance differed greatly among tick species, and we found both positive and negative cooccurrence between members of these two genera. Other tick endosymbionts (e.g., Coxiella and Rickettsiella) were associated with specific tick species. In addition, we detected Anaplasma and Bartonella in several tick species. Our results indicate that the microbial composition and richness of neotropical ticks are principally related to intrinsic factors (tick species and life stage) and collection site. Taken together, our analysis informs how tick microbiomes are structured and can help anchor our understanding of tick microbiomes from tropical environments more broadly.IMPORTANCE Blood-feeding arthropod microbiomes often play important roles in disease transmission, yet the factors that structure tick microbial communities in the Neotropics are unknown. Utilizing ticks collected from live animals in neotropical forest fragments, this study teases apart the contributions of intrinsic and extrinsic tick-associated factors on tick microbial composition as well as which specific microbes contribute to differences across tick species, tick life stages, the mammals they fed on, and the locations from where they were sampled. Furthermore, this study provides revelations of how notable tick-associated bacterial genera are interacting with other tick-associated microbes as well as the forest animals they encounter.
Subject(s)
Bacteria/isolation & purification , Microbiota , Ticks/microbiology , Animals , Forests , Larva/growth & development , Larva/microbiology , Mammals/parasitology , Nymph/growth & development , Nymph/microbiology , Panama , Ticks/growth & developmentABSTRACT
BACKGROUND: Early detection of adverse effects of novel therapies and understanding of their mechanisms could improve the safety and efficiency of drug development. We have retrospectively applied large-scale proteomics to blood samples from ILLUMINATE (Investigation of Lipid Level Management to Understand its Impact in Atherosclerotic Events), a trial of torcetrapib (a cholesterol ester transfer protein inhibitor), that involved 15 067 participants at high cardiovascular risk. ILLUMINATE was terminated at a median of 550 days because of significant absolute increases of 1.2% in cardiovascular events and 0.4% in mortality with torcetrapib. The aims of our analysis were to determine whether a proteomic analysis might reveal biological mechanisms responsible for these harmful effects and whether harmful effects of torcetrapib could have been detected early in the ILLUMINATE trial with proteomics. METHODS: A nested case-control analysis of paired plasma samples at baseline and at 3 months was performed in 249 participants assigned to torcetrapib plus atorvastatin and 223 participants assigned to atorvastatin only. Within each treatment arm, cases with events were matched to controls 1:1. Main outcomes were a survey of 1129 proteins for discovery of biological pathways altered by torcetrapib and a 9-protein risk score validated to predict myocardial infarction, stroke, heart failure, or death. RESULTS: Plasma concentrations of 200 proteins changed significantly with torcetrapib. Their pathway analysis revealed unexpected and widespread changes in immune and inflammatory functions, as well as changes in endocrine systems, including in aldosterone function and glycemic control. At baseline, 9-protein risk scores were similar in the 2 treatment arms and higher in participants with subsequent events. At 3 months, the absolute 9-protein derived risk increased in the torcetrapib plus atorvastatin arm compared with the atorvastatin-only arm by 1.08% (P=0.0004). Thirty-seven proteins changed in the direction of increased risk of 49 proteins previously associated with cardiovascular and mortality risk. CONCLUSIONS: Heretofore unknown effects of torcetrapib were revealed in immune and inflammatory functions. A protein-based risk score predicted harm from torcetrapib within just 3 months. A protein-based risk assessment embedded within a large proteomic survey may prove to be useful in the evaluation of therapies to prevent harm to patients. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00134264.
Subject(s)
Anticholesteremic Agents/adverse effects , Drug-Related Side Effects and Adverse Reactions/metabolism , Heart Failure/metabolism , Myocardial Infarction/metabolism , Quinolines/adverse effects , Stroke/metabolism , Aged , Aldosterone/metabolism , Anticholesteremic Agents/therapeutic use , Biomarkers, Pharmacological , Case-Control Studies , Cholesterol Ester Transfer Proteins/antagonists & inhibitors , Drug-Related Side Effects and Adverse Reactions/mortality , Early Diagnosis , Female , Heart Failure/etiology , Heart Failure/mortality , Humans , Male , Middle Aged , Myocardial Infarction/etiology , Myocardial Infarction/mortality , Prognosis , Prospective Studies , Proteomics , Quinolines/therapeutic use , Stroke/etiology , Stroke/mortality , Survival AnalysisABSTRACT
Little is known about how variables, such as carcass mass, affect the succession pattern of microbes in soils during decomposition. To investigate the effects of carcass mass on the soil microbial community, soils associated with swine (Sus scrofa domesticus) carcasses of four different masses were sampled until the 15th day of decomposition during the month of June in a pasture near Lincoln, Nebraska. Soils underneath swine of 1, 20, 40, and 50 kg masses were investigated in triplicate, as well as control sites not associated with a carcass. Soil microbial communities were characterized by sequencing the archaeal, bacterial (16S), and eukaryotic (18S) rRNA genes in soil samples. We conclude that time of decomposition was a significant influence on the microbial community, but carcass mass was not. The gravesoil associated with 1 kg mass carcasses differs most compared to the gravesoil associated with other carcass masses. We also identify the 15 most abundant bacterial and eukaryotic taxa, and discuss changes in their abundance as carcass decomposition progressed. Finally, we show significant decreases in alpha diversity for carcasses of differing mass in pre-carcass rupture (days 0, 1, 2, 4, 5, and 6 postmortem) versus post-carcass rupture (days 9 and 15 postmortem) microbial communities.
Subject(s)
Body Weight , Postmortem Changes , Soil Microbiology , Animals , Bacteria/genetics , Bacteria/isolation & purification , Fungi/genetics , Fungi/isolation & purification , Models, Animal , RNA, Bacterial/genetics , RNA, Ribosomal, 16S , RNA, Ribosomal, 18S , Sequence Analysis, RNA , SwineABSTRACT
Ticks are important vectors for many emerging pathogens. However, they are also infected with many symbionts and commensals, often competing for the same niches. In this paper, we characterize the microbiome of Amblyomma americanum (Acari: Ixodidae), the lone star tick, in order to better understand the evolutionary relationships between pathogens and nonpathogens. Multitag pyrosequencing of prokaryotic 16S rRNA genes (16S rRNA) was performed on 20 lone star ticks (including males, females, and nymphs). Pyrosequencing of the rickettsial sca0 gene (also known as ompA or rompA) was performed on six ticks. Female ticks had less diverse microbiomes than males and nymphs, with greater population densities of Rickettsiales. The most common members of Rickettsiales were "Candidatus Rickettsia amblyommii" and "Candidatus Midichloria mitochondrii." "Ca. Rickettsia amblyommii" was 2.6-fold more common in females than males, and there was no sequence diversity in the sca0 gene. These results are consistent with a predominantly vertical transmission pattern for "Ca. Rickettsia amblyommii."
Subject(s)
Alphaproteobacteria/classification , Alphaproteobacteria/isolation & purification , Ixodidae/microbiology , Microbiota , Alphaproteobacteria/genetics , Animals , Bacterial Outer Membrane Proteins/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Molecular Sequence Data , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNAABSTRACT
Background: The literature to date is unable to clearly characterize the appropriateness of virtual care for falls prevention services from the patient perspective. In response to COVID-19, the Falls Prevention Program (FPP) at Sunnybrook Health Sciences Centre was modified to include virtual components. We set out to uncover the experiences of this unique older-adult patient population to inform FPP quality improvement and appropriate incorporation of technology post-pandemic. Methods: FPP patients during the COVID-19 pandemic (February 2020 - February 2022) and their primary caregivers met inclusion criteria. Out of 18 eligible patients, 10 consented to participate in 20-minute, semi-structured telephone interviews conducted and transcribed by the first author. Inductive coding followed by theme generation occurred through collaborative analysis. Results: The participants (n=10) were 60% female, mean age 84 years (SD 5.8), 60% living alone, and 70% university educated. We generated three main themes: 1) First Steps First, revealed a common desire for physical and mental support and the perceived essentials of a successful FPP highlighting the importance of program length and individualized attention; 2) Overcoming Obstacles, highlighted participants' experiences overcoming barriers with technology in the context of an isolating pandemic; and 3) Advancing Care Post-Pandemic, elaborated on the appropriateness of virtual care and delved into the importance of program personalization. Conclusion: The interviewed older adults revealed agreement on the FPP's necessity and the importance of increasing program length, one-on-one interaction, and program flexibility for unique patient needs. Incorporating virtual assessment prior to in-person exercises was largely favoured and should be considered as an appropriate use of technology post-pandemic.
ABSTRACT
The identification of relevant gene targets for engineering a desired trait is a key step in combinatorial strain engineering. Here, we applied the multi-Scalar Analysis of Library Enrichments (SCALEs) approach to map ethanol tolerance onto 1,000,000 genomic-library clones in Escherichia coli. We assigned fitness scores to each of the â¼4,300 genes in E. coli, and through follow-up confirmatory studies identified 9 novel genetic targets (12 genes total) that increase E. coli ethanol tolerance (up to 6-fold improved growth). These genetic targets are involved in the processes related to cell membrane composition, translation, serine biosynthesis, and transcription regulation. Transcriptional profiling of the ethanol stress response in 5 of these ethanol-tolerant clones revealed a total of 700 genes with significantly altered expression (mapped to 615 significantly enriched gene ontology terms) across all five clones, with similar overall changes in global gene expression between two clone clusters. All ethanol-tolerant clones analyzed shared 6% of the overexpressed genes and showed enrichment for transcription regulation-related GO terms. iTRAQ-based proteomic analysis of ethanol-tolerant strains identified upregulation of proteins related to ROS mitigation, fatty acid biosynthesis, and vitamin biosynthesis as compared to the parent strain's ethanol response. The approach we outline here will be useful for engineering a variety of other traits and further improvements in alcohol tolerance.
Subject(s)
Drug Tolerance/physiology , Escherichia coli Proteins/metabolism , Escherichia coli/drug effects , Escherichia coli/physiology , Ethanol/pharmacology , Genome, Bacterial/genetics , Proteome/metabolism , Escherichia coli Proteins/genetics , Peptide Library , Proteome/geneticsABSTRACT
Objective: In response to COVID-19, the fall prevention program (FPP) at Sunnybrook Health Sciences Centre was modified to be delivered virtually. We compared patient populations assessed for the FPP virtually versus in-person to explore equitable accessibility. Methods: A retrospective chart review was performed. All patients assessed virtually from the beginning of the COVID-19 pandemic until the end of abstraction (April 25, 2022) were compared to a historic sample of patients assessed in-person beginning in January 2019. Demographics, measures of frailty, co-morbidity, and cognition were abstracted. Wilcoxon Rank Sum tests and Fisher's Exact tests were used for continuous and categorical variables, respectively. Results: Thirty patients were assessed virtually and compared to 30 in-person historic controls. Median age was 80 years (interquartile range 75-85), 82% were female, 70% were university educated, the median Clinical Frailty Score was 5 out of 9, and 87% used >5 medications. Once normalized, frailty scores showed no difference (p = 0.446). The virtual cohort showed significantly higher outdoor walking aid use (p = 0.015), reduced accuracy with clock drawing (p = 0.020), and nonsignificant trends toward using >10 medications, requiring assistance with >3 instrumental activities of daily living (IADLs), and higher treatment attendance. No significant differences were seen for time-to-treat (p = 0.423). Conclusion: Patients assessed virtually were similarly frail as the in-person controls but had increased use of walking aids, medications, IADL assistance, and cognitive impairment. In a Canadian context, frail and high socioeconomic status older adults continued to access treatment through virtual FPP assessments during the COVID-19 pandemic highlighting both the benefits of virtual care and potential inequity.
ABSTRACT
The invisible nature of economic abuse contributes to its pervasiveness. Through interviews with 14 women survivors in Canada, this study identifies the ways in which economic abuse is (in)visible to survivors. There were three major themes: "Constructing and maintaining the fairy-tale" describes how gender roles and ideas of love concealed abuse. "The normalization of financial problems in heterosexual relationships" examines how disagreements about money were normalized in ways that masked abuse. "Recognizing economic abuse" describes how breaking away from expectations was critical to recognition. These findings can aid in improving support to help survivors identify, avoid, and escape economic abuse.
ABSTRACT
BACKGROUND: Our systematic review examines the effectiveness and safety of non-pharmacologic and pharmacologic interventions in preventing or treating traumatic brain injury (TBI)-related delirium in acute care. METHODS: We searched four electronic databases (MEDLINE, EMBASE, CENTRAL/CDSR, and PsycINFO) to identify randomized controlled trials (RCTs), quasi-experimental, and observational studies. Eligible studies included adults with TBI, at least one comparator group, delirium as an outcome and took place in acute care. Two reviewers independently completed all study screening, data abstraction, and risk of bias assessment using the Cochrane risk of bias 2 tool for RCTs or risk of bias in non-randomized studies-of interventions tool for observational studies. We implemented the PROGRESS-Plus framework to describe social determinants of health (SDoH) reporting. RESULTS: We identified 20,022 citations, reviewed 301 in full text, and included eight studies in the descriptive synthesis. The mean age of study participants ranged from 32 to 62 years. 12.5% of included studies reported SDoH. Included studies had moderate-to-high risk of bias. Studies compared reorientation programs and an intervention bundle to usual care, but these interventions were not better than usual care in treating TBI-related delirium. Individual studies found that rosuvastatin and aripiprazole were more efficacious than placebo, and dexmedetomidine was more efficacious than propofol and haloperidol for preventing TBI-related delirium. No studies reported safety as the primary outcome. CONCLUSIONS: We identified efficacious pharmacologic interventions for preventing TBI-related delirium, but these studies were at moderate-to-high risk of bias, which limits our confidence in these findings. Future studies should incorporate safety outcomes, and a diverse study population, including older adults.
Subject(s)
Brain Injuries, Traumatic , Delirium , Propofol , Humans , Aged , Adult , Middle Aged , Haloperidol/therapeutic use , Brain Injuries, Traumatic/therapy , Brain Injuries, Traumatic/drug therapy , Delirium/etiology , Delirium/prevention & controlABSTRACT
Early detection of cancer is vital for the best chance of successful treatment, but half of all cancers are diagnosed at an advanced stage. A simple and reliable blood screening test applied routinely would therefore address a major unmet medical need. To gain insight into the value of protein biomarkers in early detection and stratification of cancer we determined the time course of changes in the plasma proteome of mice carrying transplanted human lung, breast, colon, or ovarian tumors. For protein measurements we used an aptamer-based assay which simultaneously measures ~ 5000 proteins. Along with tumor lineage-specific biomarkers, we also found 15 markers shared among all cancer types that included the energy metabolism enzymes glyceraldehyde-3-phosphate dehydrogenase, glucose-6-phophate isomerase and dihydrolipoyl dehydrogenase as well as several important biomarkers for maintaining protein, lipid, nucleotide, or carbohydrate balance such as tryptophanyl t-RNA synthetase and nucleoside diphosphate kinase. Using significantly altered proteins in the tumor bearing mice, we developed models to stratify tumor types and to estimate the minimum detectable tumor volume. Finally, we identified significantly enriched common and unique biological pathways among the eight tumor cell lines tested.
Subject(s)
Ovarian Neoplasms , Proteome , Female , Humans , Mice , Animals , Proteome/metabolism , Biomarkers, Tumor/metabolism , Energy Metabolism , Cell Line, TumorABSTRACT
An assay has been developed in which the activity of an ubiquinol oxidase from Escherichia coli, cytochrome bo(3) (cbo(3)), is determined as a function of the hydrophobic substrate ubiquinol-10 (UQ-10) in tethered bilayer lipid membranes (tBLMs). UQ-10 was added in situ, while the enzyme activity and the UQ-10 concentration in the membrane have been determined by cyclic voltammetry. Cbo(3) is inhibited by UQ-10 at concentrations above 5-10 pmol/cm(2), while product inhibition is absent. Cyclic voltammetry has also been used to characterise the effects of three inhibitors; cyanide, inhibiting oxygen reduction; 2-n-Heptyl-4-hydroxyquinoline N-oxide (HQNO), inhibiting the quinone oxidation and Zn(II), thought to block the proton channels required for oxygen reduction and proton pumping activity. The electrochemical behaviour of cbo(3) inhibited with HQNO and Zn(II) is almost identical, suggesting that Zn(II) ions inhibit the enzyme reduction by quinol, rather than oxygen reduction. This suggests that at Zn(II) concentration below 50µM the proton release of cbo(3) is inhibited, but not the proton uptake required to reduce oxygen to water.
Subject(s)
Cytochromes/metabolism , Escherichia coli Proteins/metabolism , Lipid Bilayers/metabolism , Ubiquinone/analogs & derivatives , Biocatalysis/drug effects , Cytochrome b Group , Cytochromes/antagonists & inhibitors , Dose-Response Relationship, Drug , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Electrodes , Escherichia coli Proteins/antagonists & inhibitors , Hydrophobic and Hydrophilic Interactions , Hydroxyquinolines/pharmacology , Kinetics , Lipid Bilayers/chemistry , Oxidation-Reduction/drug effects , Oxidoreductases/metabolism , Sodium Cyanide/pharmacology , Substrate Specificity , Ubiquinone/chemistry , Ubiquinone/metabolism , Zinc Sulfate/pharmacologyABSTRACT
We have developed a simple native-like surface-tethered membrane system to investigate the activity of cbo(3) (cytochrome bo(3)), a terminal oxidase in Escherichia coli. The tethered membranes consist of E. coli inner-membrane extracts mixed with additional E. coli lipids containing various amounts of the cbo(3) substrate UQ-10 (ubiquinol-10). Tethered membranes are formed by self-assembly from vesicles on to gold electrodes functionalized with cholesterol derivatives. cbo(3) activity was monitored using CV (cyclic voltammetry) with electron transfer to cbo(3) mediated by UQ-10. The apparent K(m) for oxygen with this system is 1.1+/-0.4 microM, in good agreement with values reported in the literature for whole-cell experiments and for purified cbo(3). Increasing the concentration of lipophilic UQ-10 in the membrane leads to an increase in cbo(3) activity. The activity of cbo(3) with long-chain ubiquinones appears to be different from previous reports using short-chain substrate analogues such as UQ-1 in that typical Michaelis-Menten kinetics are not observed using UQ-10. This native-like membrane model thus provides new insights into the interaction of transmembrane enzymes with hydrophobic substrates which contrasts with studies using hydrophilic UQ analogues.
Subject(s)
Cell Membrane/enzymology , Cytochromes/metabolism , Cytochrome b Group , Cytochromes/genetics , Electrochemistry , Electrodes , Enzyme Activation , Escherichia coli Proteins , Kinetics , Oxygen/metabolismABSTRACT
Background Chronic kidney disease (CKD) confers increased cardiovascular risk, not fully explained by traditional factors. Proteins regulate biological processes and inform the risk of diseases. Thus, in 938 patients with stable coronary heart disease from the Heart and Soul cohort, we quantified 1054 plasma proteins using modified aptamers (SOMAscan) to: (1) discern how reduced glomerular filtration influences the circulating proteome, (2) learn of the importance of kidney function to the prognostic information contained in recently identified protein cardiovascular risk biomarkers, and (3) identify novel and even unique cardiovascular risk biomarkers among individuals with CKD. Methods and Results Plasma protein levels were correlated to estimated glomerular filtration rate (eGFR) using Spearman-rank correlation coefficients. Cox proportional hazard models were used to estimate the association between individual protein levels and the risk of the cardiovascular outcome (first among myocardial infarction, stroke, heart failure hospitalization, or mortality). Seven hundred and nine (67.3%) plasma proteins correlated with eGFR at P<0.05 (ρ 0.06-0.74); 218 (20.7%) proteins correlated with eGFR moderately or strongly (ρ 0.2-0.74). Among the previously identified 196 protein cardiovascular biomarkers, just 87 remained prognostic after correction for eGFR. Among patients with CKD (eGFR <60 mL/min per 1.73 m2), we identified 21 protein cardiovascular risk biomarkers of which 8 are unique to CKD. Conclusions CKD broadly alters the composition of the circulating proteome. We describe protein biomarkers capable of predicting cardiovascular risk independently of glomerular filtration, and those that are prognostic of cardiovascular risk specifically in patients with CKD and even unique to patients with CKD.
Subject(s)
Biomarkers/blood , Coronary Disease/blood , Glomerular Filtration Rate , Proteome , Renal Insufficiency, Chronic/blood , Aged , Cohort Studies , Coronary Disease/complications , Female , Heart Disease Risk Factors , Humans , Male , Middle Aged , Renal Insufficiency, Chronic/complicationsABSTRACT
OBJECTIVE: To assess the effects of empagliflozin, a selective sodium-glucose cotransporter 2 (SGLT2) inhibitor, on broad biological systems through proteomics. RESEARCH DESIGN AND METHODS: Aptamer-based proteomics was used to quantify 3,713 proteins in 144 paired plasma samples obtained from 72 participants across the spectrum of glucose tolerance before and after 4 weeks of empagliflozin 25 mg/day. The biology of the plasma proteins significantly changed by empagliflozin (at false discovery rate-corrected P < 0.05) was discerned through Ingenuity Pathway Analysis. RESULTS: Empagliflozin significantly affected levels of 43 proteins, 6 related to cardiomyocyte function (fatty acid-binding protein 3 and 4 [FABPA], neurotrophic receptor tyrosine kinase, renin, thrombospondin 4, and leptin receptor), 5 to iron handling (ferritin heavy chain 1, transferrin receptor protein 1, neogenin, growth differentiation factor 2 [GDF2], and ß2-microglobulin), and 1 to sphingosine/ceramide metabolism (neutral ceramidase), a known pathway of cardiovascular disease. Among the protein changes achieving the strongest statistical significance, insulin-like binding factor protein-1 (IGFBP-1), transgelin-2, FABPA, GDF15, and sulphydryl oxidase 2 precursor were increased, while ferritin, thrombospondin 3, and Rearranged during Transfection (RET) were decreased by empagliflozin administration. CONCLUSIONS: SGLT2 inhibition is associated, directly or indirectly, with multiple biological effects, including changes in markers of cardiomyocyte contraction/relaxation, iron handling, and other metabolic and renal targets. The most significant differences were detected in protein species (GDF15, ferritin, IGFBP-1, and FABP) potentially related to the clinical and metabolic changes that were actually measured in the same patients. These novel results may inform further studies using targeted proteomics and a prospective design.
Subject(s)
Benzhydryl Compounds/pharmacology , Glucosides/pharmacology , Proteome/drug effects , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Aged , Biomarkers/analysis , Biomarkers/blood , Blood Proteins/drug effects , Blood Proteins/metabolism , Female , Glucose/metabolism , Humans , Hypoglycemic Agents/pharmacology , Male , Middle Aged , Prospective Studies , Proteome/analysis , Proteome/metabolism , Proteomics/methods , Signal Transduction/drug effectsABSTRACT
Quinone oxidoreductases are a class of membrane enzymes that catalyse the oxidation or reduction of membrane-bound quinols/quinones. The conversion of quinone/quinol by these enzymes is difficult to study because of the hydrophobic nature of the enzymes and their substrates. We describe some biochemical properties of quinones and quinone oxidoreductases and then look in more detail at two model membranes that can be used to study quinone oxidoreductases in a native-like membrane environment with their native lipophilic quinone substrates. The results obtained with these model membranes are compared with classical enzyme assays that use water-soluble quinone analogues.
Subject(s)
Electrodes , Membrane Lipids/chemistry , Membranes, Artificial , NAD(P)H Dehydrogenase (Quinone)/metabolism , Hydrophobic and Hydrophilic Interactions , Quinones/metabolismABSTRACT
Inhibition of glycogen synthase kinase 3beta (GSK3beta) as a consequence of its phosphorylation by protein kinase B/Akt (PKB/Akt) has been implicated in cardiac myocyte hypertrophy in response to endothelin-1 or phenylephrine. We examined the regulation of GSK3alpha (which we show to constitute a significant proportion of the myocyte GSK3 pool) and GSK3beta in cardiac myocytes. Although endothelin increases phosphorylation of GSK3 and decreases its activity, the response is less than that induced by insulin (which does not promote cardiac myocyte hypertrophy). GSK3 phosphorylation induced by endothelin requires signalling through the extracellular signal-regulated kinase 1/2 (ERK1/2) cascade and not the PKB/Akt pathway, whereas the reverse is true for insulin. Cardiac myocyte hypertrophy involves changes in morphology, and in gene and protein expression. The potent GSK3 inhibitor 1-azakenpaullone increases myocyte area as a consequence of increased cell length whereas phenylephrine increases both length and width. Azakenpaullone or insulin promotes AP1 transcription factor binding to an AP1 consensus oligonucleotide, but this was significantly less than that induced by endothelin and derived principally from increased binding of JunB protein, the expression of which was increased. Azakenpaullone promotes significant changes in gene expression (assessed by Affymetrix microarrays), but the overall response is less than with endothelin and there is little overlap between the genes identified. Thus, although GSK3 may contribute to cardiac myocyte hypertrophy in some respects (and presumably plays an important role in myocyte metabolism), it does not appear to contribute as significantly to the response induced by endothelin as has been maintained.
Subject(s)
Glycogen Synthase Kinase 3/metabolism , Myocytes, Cardiac/enzymology , Animals , Benzazepines/pharmacology , Cells, Cultured , Endothelin-1/physiology , Enzyme Inhibitors/pharmacology , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation, Enzymologic/drug effects , Glycogen Synthase Kinase 3/antagonists & inhibitors , Glycogen Synthase Kinase 3 beta , Indoles/pharmacology , Insulin/pharmacology , Myocytes, Cardiac/cytology , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Tetradecanoylphorbol Acetate/pharmacology , Transcription Factor AP-1/metabolismABSTRACT
PURPOSE: To explore top-ranked plasma proteins related to neovascular age-related macular degeneration (AMD) and geographic atrophy (GA), and explore pathways related to neovascular AMD and GA. METHODS: We conducted a pilot study of patients with neovascular AMD (n = 10), GA (n = 10), and age-matched cataract controls (n = 10) who were recruited into an AMD registry. We measured 4001 proteins in ethylenediaminetetraacetic acid plasma samples using an aptamer-based proteomic technology. Relative concentrations of each of 4001 proteins were log (base 2) transformed and compared between cases of neovascular AMD and GA versus controls using linear regression. Pathway analysis was conducted using pathways downloaded from Reactome. RESULTS: In this pilot study, higher levels of vinculin and lower levels of CD177 were found in patients with neovascular AMD compared with controls. Neuregulin-4 was higher and soluble intercellular adhesion molecule-1 was lower in patients with GA compared with controls. For neovascular AMD, cargo trafficking to the periciliary membrane, fibroblast growth factor receptor 3b ligand binding and activation, and vascular endothelial growth factor-related pathways were in the top ranked pathways. The top-ranked pathways for GA included several related to ErbB4 signaling. CONCLUSIONS: We found different proteins and different pathways associated with neovascular AMD and GA. Vinculin and some of the top-ranked pathways have been previously associated with AMD, whereas others have not been described. TRANSLATIONAL RELEVANCE: Biomarkers identified in plasma likely reflect systemic alterations in protein expression and may improve our understanding of the mechanisms leading to AMD.