9 research outputs found
Lipolytic response of adipose tissue and metabolic adaptations to long periods of fasting in red tilapia (Oreochromis sp., Teleostei: Cichlidae)
ABSTRACT Adaptive changes of carbohydrate and lipid metabolism induced by 7, 15, 30, 60, 90, 150 and 200 days of fasting were investigated in red tilapia (Oreochromis sp.). Plasma glucose, lactate and free fatty acids (FFA) levels, liver and muscle glycogen and total lipid contents and rates of FFA release from mesenteric adipose tissue (MAT) were measured. Plasma glucose levels showed significant differences only after 90 days of fasting, when glycemia was 34% lower (50±5mg.dL-1) than fed fish values (74±1mg.dL-1), remaining relatively constant until 200 days of fasting. The content of liver glycogen ("15%) in fed tilapia fell 40% in 7 days of food deprivation. In 60, 90 and 150 days of fasting, plasma FFA levels increased 49%, 64% and 90%, respectively, compared to fed fish values. In agreement with the increase in plasma FFA, fasting induced a clear increase in lipolytic activity of MAT incubated in vitro. Addition of isobutylmethylxanthine (cAMP-phosphodiesterase inhibitor) and isoproterenol (non selective beta adrenergic agonist) to the incubation medium induced a reduction of lipolysis in fasted fish, differently to what was observed in mammal adipose tissue. This study allowed a physiological assessment of red tilapia response to starvation
Fatty acid synthesis and generation of glycerol-3-phosphate in brown adipose tissue from rats fed a cafeteria diet
In vivo fatty acid synthesis and the pathways of glycerol-3-phosphate (G3P) production were investigated in brown adipose tissue (BAT) from rats fed a cafeteria diet for 3 weeks. In spite of BAT activation, the diet promoted an increase in the carcass fatty acid content. Plasma insulin levels were markedly increased in cafeteria diet-fed rats. Two insulin-sensitive processes, in vivo fatty acid synthesis and in vivo glucose uptake (which was used to evaluate G3P generation via glycolysis) were increased in BAT from rats fed the cafeteria diet. Direct glycerol phosphorylation, evaluated by glycerokinase (GyK) activity and incorporation of [U-(14)C]glycerol into triacylglycerol (TAG)-glycerol, was also markedly increased in BAT from these rats. In contrast, the cafeteria diet induced a marked reduction of BAT glyceroneogenesis, evaluated by phosphoenolpyruvate carboxykinase-C activity and incorporation of [1-(14)C]pyruvate into TAG-glycerol. BAT denervation resulted in an approximately 50% reduction of GyK activity, but did not significantly affect BAT in vivo fatty acid synthesis, in vivo glucose uptake, or glyceroneogenesis. The data suggest that the supply of G3P for BAT TAG synthesis can be adjusted independently from the sympathetic nervous system and solely by reciprocal changes in the generation of G3P via glycolysis and via glyceroneogenesis, with no participation of direct phosphorylation of glycerol by GyK
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Comparative Impact of Depressive Symptoms and FEV1% on Chronic Obstructive Pulmonary Disease.
Rationale: Individuals with chronic obstructive pulmonary disease (COPD) have a high prevalence of depression, which is associated with increased COPD hospitalizations and readmissions. Objectives: Examine the impact of depressive symptoms compared with FEV1% on COPD morbidity. Methods: Using longitudinal data from individuals with COPD in the Subpopulations and Intermediate Outcome Measures in COPD Study, longitudinal growth analysis was performed to assess COPD morbidity by assessing differences in baseline 6-minute walk distance and patient reported outcomes (PROs) and their rate of change over time explained by depressive symptoms or lung function, as measured by Hospital Anxiety and Depression Scale or FEV1% respectively. PROs consisted of in-person completion of St. George's Respiratory Questionnaire, COPD Assessment Test, Functional Assessment of Chronic Illness Therapy Fatigue, and Modified Medical Research Council Dyspnea Scale measures. Results: Of the individuals analyzed (nâ=â1,830), 43% were female, 81% Caucasian with meanâ±âSD age of 65.1â±â8.1, and 52.7â±â27.5 pack-years smoking. Meanâ±âSD FEV1% was 60.9â±â23.0% and 20% had clinically significant depressive symptoms. Adjusted models showed higher Hospital Anxiety and Depression Scale scores and lower FEV1% each were associated with worse PROs at baseline (Pââ©œâ0.001). Depression accounted for more baseline variance in St. George's Respiratory Questionnaire, COPD Assessment Test, and Functional Assessment of Chronic Illness Therapy Fatigue than FEV1%, explaining 30-67% of heterogeneity. FEV1% accounted for more baseline variance in Modified Medical Research Council Dyspnea Scale and 6-minute walk distance than depression, explaining 16-32% of heterogeneity. Depressive symptoms accounted for 3-17% variance in change over time in PROs. In contrast, FEV1% accounted for 1-4% variance over time in PROs. Conclusions: Depression is more strongly associated with many PROs at baseline and their change over time compared with FEV1%. Recognizing and incorporating the impact of depressive symptoms into individualized care may improve COPD outcomes
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Identification of Sputum Biomarkers Predictive of Pulmonary Exacerbations in COPD
BackgroundImproved understanding of the pathways associated with airway pathophysiologic features in COPD will identify new predictive biomarkers and novel therapeutic targets.Research questionWhich physiologic pathways are altered in the airways of patients with COPD and will predict exacerbations?Study design and methodsWe applied a mass spectrometric panel of metabolomic biomarkers related to mucus hydration and inflammation to sputa from the multicenter Subpopulations and Intermediate Outcome Measures in COPD Study. Biomarkers elevated in sputa from patients with COPD were evaluated for relationships to measures of COPD disease severity and their ability to predict future exacerbations.ResultsSputum supernatants from 980 patients were analyzed: 77 healthy nonsmokers, 341 smokers with preserved spirometry, and 562 patients with COPD (178 with Global Initiative on Chronic Obstructive Lung Disease [GOLD] stage 1 disease, 303 with GOLD stage 2 disease, and 81 with GOLD stage 3 disease) were analyzed. Biomarkers from multiple pathways were elevated in COPD and correlated with sputum neutrophil counts. Among the most significant analytes (false discovery rate, 0.1) were sialic acid, hypoxanthine, xanthine, methylthioadenosine, adenine, and glutathione. Sialic acid and hypoxanthine were associated strongly with measures of disease severity, and elevation of these biomarkers was associated with shorter time to exacerbation and improved prediction models of future exacerbations.InterpretationBiomarker evaluation implicated pathways involved in mucus hydration, adenosine metabolism, methionine salvage, and oxidative stress in COPD airway pathophysiologic characteristics. Therapies that target these pathways may be of benefit in COPD, and a simple model adding sputum-soluble phase biomarkers improves prediction of pulmonary exacerbations.Trial registryClinicalTrials.gov; No.: NCT01969344; URL: www.Clinicaltrialsgov
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Bronchodilator Responsiveness in Tobacco-Exposed People With or Without COPD
BackgroundBronchodilator responsiveness (BDR) in obstructive lung disease varies over time and may be associated with distinct clinical features.Research questionIs consistent BDR over time (always present) differentially associated with obstructive lung disease features relative to inconsistent (sometimes present) or never (never present) BDR in tobacco-exposed people with or without COPD?Study design and methodsWe retrospectively analyzed data from 2,269 tobacco-exposed participants in the Subpopulations and Intermediate Outcome Measures in COPD Study with or without COPD. We used various BDR definitions: change of â„ 200 mL and â„ 12% in FEV1 (FEV1-BDR), change in FVC (FVC-BDR), and change in in FEV1, FVC or both (ATS-BDR). Using generalized linear models adjusted for demographics, smoking history, FEV1 % predicted after bronchodilator administration, and number of visits that the participant completed, we assessed the association of BDR group: (1) consistent BDR, (2) inconsistent BDR, and (3) never BDR with asthma, CT scan features, blood eosinophil levels, and FEV1 decline in participants without COPD (Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage 0) and the entire cohort (participants with or without COPD).ResultsBoth consistent and inconsistent ATS-BDR were associated with asthma history and greater small airways disease (%parametric response mapping functional small airways disease) relative to never ATS-BDR in participants with GOLD stage 0 disease and the entire cohort. We observed similar findings using FEV1-BDR and FVC-BDR definitions. Eosinophils did not vary consistently among BDR groups. Consistent BDR was associated with FEV1 decline over time relative to never BDR in the entire cohort. In participants with GOLD stage 0 disease, both the inconsistent ATS-BDR group (OR, 3.20; 95% CI, 2.21-4.66; P < .001) and consistent ATS-BDR group (OR, 9.48; 95% CI, 3.77-29.12; P < .001) were associated with progression to COPD relative to the never ATS-BDR group.InterpretationDemonstration of BDR, even once, describes an obstructive lung disease phenotype with a history of asthma and greater small airways disease. Consistent demonstration of BDR indicated a high risk of lung function decline over time in the entire cohort and was associated with higher risk of progression to COPD in patients with GOLD stage 0 disease
Pharmaceutical pollution of the world's rivers
Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the scale of the problem from a global perspective. Furthermore, comparison of the existing data, generated for different studies/regions/continents, is challenging due to the vast differences between the analytical methodologies employed. Here, we present a global-scale study of API pollution in 258 of the world's rivers, representing the environmental influence of 471.4 million people across 137 geographic regions. Samples were obtained from 1,052 locations in 104 countries (representing all continents and 36 countries not previously studied for API contamination) and analyzed for 61 APIs. Highest cumulative API concentrations were observed in sub-Saharan Africa, south Asia, and South America. The most contaminated sites were in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing. The most frequently detected APIs were carbamazepine, metformin, and caffeine (a compound also arising from lifestyle use), which were detected at over half of the sites monitored. Concentrations of at least one API at 25.7% of the sampling sites were greater than concentrations considered safe for aquatic organisms, or which are of concern in terms of selection for antimicrobial resistance. Therefore, pharmaceutical pollution poses a global threat to environmental and human health, as well as to delivery of the United Nations Sustainable Development Goals.N
Pharmaceutical pollution of the world's rivers
Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the scale of the problem from a global perspective. Furthermore, comparison of the existing data, generated for different studies/regions/continents, is challenging due to the vast differences between the analytical methodologies employed. Here, we present a global-scale study of API pollution in 258 of the world's rivers, representing the environmental influence of 471.4 million people across 137 geographic regions. Samples were obtained from 1,052 locations in 104 countries (representing all continents and 36 countries not previously studied for API contamination) and analyzed for 61 APIs. Highest cumulative API concentrations were observed in sub-Saharan Africa, south Asia, and South America. The most contaminated sites were in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing. The most frequently detected APIs were carbamazepine, metformin, and caffeine (a compound also arising from lifestyle use), which were detected at over half of the sites monitored. Concentrations of at least one API at 25.7% of the sampling sites were greater than concentrations considered safe for aquatic organisms, or which are of concern in terms of selection for antimicrobial resistance. Therefore, pharmaceutical pollution poses a global threat to environmental and human health, as well as to delivery of the United Nations Sustainable Development Goals