27 research outputs found
Cholesterol-Ester Transfer Protein Alters M1 and M2 Macrophage Polarization and Worsens Experimental Elastase-Induced Pulmonary Emphysema
Cholesterol-ester transfer protein (CETP) plays a role in atherosclerosis, the inflammatory response to endotoxemia and in experimental and human sepsis. Functional alterations in lipoprotein (LP) metabolism and immune cell populations, including macrophages, occur during sepsis and may be related to comorbidities such as chronic obstructive pulmonary disease (COPD). Macrophages are significantly associated with pulmonary emphysema, and depending on the microenvironment, might exhibit an M1 or M2 phenotype. Macrophages derived from the peritoneum and bone marrow reveal CETP that contributes to its plasma concentration. Here, we evaluated the role of CETP in macrophage polarization and elastase-induced pulmonary emphysema (ELA) in human CETP-expressing transgenic (huCETP) (line 5203, C57BL6/J background) male mice and compared it to their wild type littermates. We showed that bone marrow-derived macrophages from huCETP mice reduce polarization toward the M1 phenotype, but with increased IL-10. Compared to WT, huCETP mice exposed to elastase showed worsened lung function with an increased mean linear intercept (Lm), reflecting airspace enlargement resulting from parenchymal destruction with increased expression of arginase-1 and IL-10, which are M2 markers. The cytokine profile revealed increased IL-6 in plasma and TNF, and IL-10 in bronchoalveolar lavage (BAL), corroborating with the lung immunohistochemistry in the huCETP-ELA group compared to WT-ELA. Elastase treatment in the huCETP group increased VLDL-C and reduced HDL-C. Elastase-induced pulmonary emphysema in huCETP mice promotes lung M2-like phenotype with a deleterious effect in experimental COPD, corroborating the in vitro result in which CETP promoted M2 macrophage polarization. Our results suggest that CETP is associated with inflammatory response and influences the role of macrophages in COPD
First international descriptive and interventional survey for cholesterol and non-cholesterol sterol determination by gas- and liquid- chromatography–Urgent need for harmonisation of analytical methods
Serum concentrations of lathosterol, the plant sterols campesterol and sitosterol and the cholesterol metabolite 5α-cholestanol are widely used as surrogate markers of cholesterol synthesis and absorption, respectively. Increasing numbers of laboratories utilize a broad spectrum of well-established and recently developed methods for the determination of cholesterol and non-cholesterol sterols (NCS). In order to evaluate the quality of these measurements and to identify possible sources of analytical errors our group initiated the first international survey for cholesterol and NCS. The cholesterol and NCS survey was structured as a two-part survey which took place in the years 2013 and 2014. The first survey part was designed as descriptive, providing information about the variation of reported results from different laboratories. A set of two lyophilized pooled sera (A and B) was sent to twenty laboratories specialized in chromatographic lipid analysis. The different sterols were quantified either by gas chromatography-flame ionization detection, gas chromatography- or liquid chromatography-mass selective detection. The participants were requested to determine cholesterol and NCS concentrations in the provided samples as part of their normal laboratory routine. The second part was designed as interventional survey. Twenty-two laboratories agreed to participate and received again two different lyophilized pooled sera (C and D). In contrast to the first international survey, each participant received standard stock solutions with defined concentrations of cholesterol and NCS. The participants were requested to use diluted calibration solutions from the provided standard stock solutions for quantification of cholesterol and NCS. In both surveys, each laboratory used its own internal standard (5α-cholestane, epicoprostanol or deuterium labelled sterols).
Main outcome of the survey was, that unacceptably high interlaboratory variations for cholesterol and NCS concentrations are reported, even when the individual laboratories used the same calibration material. We discuss different sources of errors and recommend all laboratories analysing cholesterol and NCS to participate in regular quality control programs
Influence of plasma lipases and lipid transfer proteins on the transfer of phospholipidis and free cholesterol from lipid emulsion to lipoproteins
A atividade das lipases plasmaticas (LLP e LH) e das proteinas de transferencia de lipides (CETP e PLTP) sao fatores envolvidos na geracao, maturacao e composicao quimica da HDL. No presente estudo, foi avaliada a influencia das lipases plasmaticas e das proteinas de transferencia de lipides sobre a transferencia de colesterol livre (CL) e fosfolipides (FL) de emulsoes lipidicas marcadas com 3 H-CL e l4C-FL para as lipoproteinas do plasma de seres humanos, ratos e camundongos. A influencia das lipases plasmaticas foi avaliada in vitro no plasma de seres humanos (controle, pos-heparina e pos-heparina com inibidor de lipases) e no plasma de ratos (controle e pos-heparina) incubados COM 3H-CL/l4C-FL-emuisao lipidica e in vivo em ratos hepatectomizados controle e heparinizados, que receberam intra-arterialmente a 3 H-FL/14-CL-emulsao lipidica. As lipases plasmaticas estimulam a transferencia de FL da emulsao para a HDL, mas nao alteram a transferencia de CL. Os processos de transferencia de FL e CL da emulsao para a HDL sao independentes: a transferencia de FL e mais rapida e aproximadamente 2 vezes maior que a do CL. A influencia das proteinas de transferencia de lipides foi avaliada in vitro no plasma de seres humanos (controle e com adicao de anticorpo monoclonal anti-CETP -TP2) e em plasma de camundongos (controle e transgenicos que expressam CETP humana) incubados com l4C-FL-emulsao lipidica. A CETP influencia a transferencia de FL no plasma de seres humanos, pois sua inibicao reduziu a transferencia de l4C-FL da emulsao lipidica para a HDL, e nao particpa na transferencia de FL no plasma de camundongosBV UNIFESP: Teses e dissertaçõe
A snapshot of the nutritional status of Crohn’s disease among adolescents in Brazil: a prospective cross-sectional study
Abstract
Background
The relationship between nutrition and Crohn’s disease (CD) is complex and involves several therapeutic possibilities including: nutrition treatment for malnourished patients, optimization of growth and development, prevention of osteoporosis, first-line therapy for active disease, and maintenance of disease remission. In children and adolescents with CD, malnutrition is a common problem that adversely affects the prognosis. In at-risk adolescent CD patients, it is important to assess body composition, food intake, energy expenditure, nutrient balance and serum levels of nutrients before planning interventions for this population. The aim of this study was to provide a snapshot of the nutritional status of adolescents with CD in Brazil.
Methods
We prospectively selected 22 patients with mildly to moderately active CD, 29 patients with inactive CD and 35 controls (first-degree relatives of and in the same age bracket as the CD patients). The age range of participants was between 13.2 and 19.4 years old. We collected anthropometric data including weight, height, and body mass index (BMI), which were expressed as Z scores: weight-for-age, height-for-age and BMI-for-age, respectively, as well as using bioimpedance to determine body composition and assessing the Tanner stage. We also assessed macronutrients and micronutrients (serum levels and dietary intake of both). We used the chi-square test to determine whether any of the studied variables were associated with inactive or active CD. The level of significance was set at 5 % (p < 0.05). We have written informed parental consent for participation for any minors and written informed consent for any participants that were adults.
Results
The mean values for lean body mass, Tanner stage, height-for-age Z score and BMI-for-age Z score were lower in the active CD group than in the inactive CD and control groups (p < 0.05 for both). Compared with the controls, the CD patients showed significant differences in terms of the quality of dietary intake (particularly in caloric intake, dietary protein intake, dietary fiber intake, and micronutrient intake), which were reflected in the serum levels of nutrients, mainly vitamins A and E (p < 0.05).
Conclusions
Adolescents with CD (including those with mildly to moderately active or inactive disease) have a nutritional risk, which makes it important to conduct nutritional assessments in such patients
Electronegative Low-Density Lipoprotein is Associated with Dense Low-Density Lipoprotein in Subjects with Different Levels of Cardiovascular Risk
Dyslipidemias and physicochemical changes in low-density lipoprotein (LDL) are very important factors for the development of coronary artery disease (CAD). However, pathophysiological properties of electronegative low-density lipoprotein [LDL(-)] remain a controversial issue. Our objective was to investigate LDL(-) content in LDL and its subfractions (phenotypes A and B) of subjects with different cardiovascular risk. Seventy-three subjects were randomized into three groups: normolipidemic (N; n = 30) and hypercholesterolemic (HC; n = 33) subjects and patients with CAD (n = 10). After fasting, blood samples were collected and total, dense and light LDL were isolated. LDL(-) content in total LDL and its subfractions was determined by ELISA. LDL(-) content in total LDL was lower in the N group as compared to the HC (P < 0.001) and CAD (P = 0.006) groups. In the total sample and in those of the N, HC, and CAD groups, LDL(-) content in dense LDL was higher than in light LDL (P = 0.001, 0.001, 0.001, and 0.033, respectively) The impact of LDL(-) on cardiovascular risk was reinforced when LDL(-) content in LDL showed itself to have a positive association with total cholesterol (beta = 0.003; P < 0.001), LDL-C (beta = 0.003; p < 0.001), and non-HDL-C (beta = 0.003; P < 0.001) and a negative association with HDL-C (beta = -0.32; P = 0.04). Therefore, LDL(-) is an important biomarker that showed association with the lipid profile and the level of cardiovascular risk.FAPESP[04/11792-6
Chromatographic analysis of lipid fractions in healthy dogs and dogs with obesity or hyperadrenocorticism
Obesity and endogenous hyperadrenocorticism (HAC) are common clinical conditions in veterinary practice, and both conditions have clinical and laboratory similarities, Such as weight gain and dyslipidemia. The objective of the present study was to characterize and compare the lipid profiles and plasma lipoprotein fractions in healthy dogs (n = 10), in obese dogs (n = 10), and in dogs with HAC (n = 6). All of the dogs were client owned. The lipoproteins were separated by fast protein liquid chromatography, and the plasma concentrations of total cholesterol and total triacylglycerol (TAG) were determined by enzymatic methods. When compared with the healthy and obese groups, dogs with HAC had a significant increase (P < 0.01) in the total concentrations of TAGs and cholesterol (CHOL), with higher distribution in the very low-density lipoprotein (VLDL)-CHOL fractions. In addition, the distributions of the high-density lipoprotein (HDL)-CHOL and HDL-TAG fractions were significantly lower (P < 0.01) in dogs with HAC than in healthy dogs. Considering the animals in this study, it was determined that the dogs with HAC differed significantly from the healthy and obese dogs regarding the metabolism of CHOL and TAG, as well as their VLDL and HDL fractions. Similar laboratory findings could allow veterinarians to distinguish obese dogs from those with HAC. In addition, dogs with HAC may be at higher risk for developing metabolic and atherosclerotic complications
Phytosterols Supplementation Reduces Endothelin-1 Plasma Concentration in Moderately Hypercholesterolemic Individuals Independently of Their Cholesterol-Lowering Properties
Experimental and clinical studies have demonstrated the effect of phytosterols (PS) on reducing plasma levels of cholesterol and LDL-c, but the effects of plant sterols beyond cholesterol-lowering are still questionable. Since inflammation and endothelial dysfunction are involved in the pathogenesis of atherosclerosis, this study aims to evaluate the effect of PS on biomarkers involved in atherosclerosis progression and whether these effects are independent of alterations in plasma LDL-c levels. Thirty-eight moderately hypercholesterolemic volunteers (58 ± 12 years; LDL-c ≥ 130 mg/dL) were randomly assigned to consume 400 mL/day of soy milk or soy milk + PS (1.6 g/day) for 4 weeks in a double-blind, placebo-controlled, cross-over study. Blood samples were collected and lipid profiles and biomarkers for inflammation and endothelial dysfunction determined. The results showed that PS treatment reduced endothelin-1 plasma concentration by 11% (p = 0.02) independently of variations in plasma levels of LDL-c. No alterations were observed regarding fibrinogen, IL-6, hs-CRP, SAA, TNFα, or VCAM-1 between placebo and PS-treated groups. Furthermore, PS reduced total plasma cholesterol concentration (−5,5%, p < 0.001), LDL-c (−6.4%, p < 0.05), triglycerides (−8.3%, p < 0.05), and apo B (−5.3%, p < 0.05), without changing HDL-c concentration (p > 0.05). Therefore, PS supplementation effectively lowers endothelin-1 independently of the reductions in plasma levels of LDL-c, contributing to the comprehension of the effect of plant sterols on endothelial function and prevention of cardiovascular diseases
HDL size is more accurate than HDL cholesterol to predict carotid subclinical atherosclerosis in individuals classified as low cardiovascular risk.
Misclassification of patients as low cardiovascular risk (LCR) remains a major concern and challenges the efficacy of traditional risk markers. Due to its strong association with cholesterol acceptor capacity, high-density lipoprotein (HDL) size has been appointed as a potential risk marker. Hence, we investigate whether HDL size improves the predictive value of HDL-cholesterol in the identification of carotid atherosclerotic burden in individuals stratified to be at LCR.284 individuals (40-75 years) classified as LCR by the current US guidelines were selected in a three-step procedure from primary care centers of the cities of Campinas and Americana, SP, Brazil. Apolipoprotein B-containing lipoproteins were precipitated by polyethylene glycol and HDL size was measured by dynamic light scattering (DLS) technique. Participants were classified in tertiles of HDL size (<7.57; 7.57-8.22; >8.22 nm). Carotid intima-media thickness (cIMT) <0.90 mm (80th percentile) was determined by high resolution ultrasonography and multivariate ordinal regression models were used to assess the association between cIMT across HDL size and levels of lipid parameters. HDL-cholesterol was not associated with cIMT. In contrast, HDL size >8.22 nm was independently associated with low cIMT in either unadjusted and adjusted models for age, gender and Homeostasis Model Assessment 2 index for insulin sensitivity, ethnicity and body mass index (Odds ratio 0.23; 95% confidence interval 0.07-0.74, p = 0.013).The mean HDL size estimated with DLS constitutes a better predictor for subclinical carotid atherosclerosis than the conventional measurements of plasma HDL-cholesterol in individuals classified as LCR
1-Methyl-D-Tryptophan Potentiates TGF-β-Induced Epithelial-Mesenchymal Transition in T24 Human Bladder Cancer Cells
<div><p>Immune escape and metastasis are the hallmarks of several types of cancer including bladder cancer. One of the mechanisms involved in these processes has been linked to indoleamine 2,3-dioxygenase (IDO). Although IDO is classically recognized for its immunomodulatory property, it has presented nonimmunological effects in some tumors. TGF-β1 is believed to contribute to carcinoma development by modulating immunossupressive molecules, including IDO. In addition, TGF-β1 induces the epithelial-mesenchymal transition (EMT), which is a critical step in the tumor invasiveness and metastasis. We investigated the role of MT and IDO modulation in the induction of EMT by TGF-β1 in T24 human bladder carcinoma cells. When T24 cells were incubated with the IDO inhibitor (MT, 1-methyl-D-tryptophan), with TGF-β1, and with MT+TGF-β1, a significant decrease of IDO expression and activity was observed. In addition, downregulation of e-cadherin and upregulation of n-cadherin and EMT transcription factors were induced by the treatments, confirming the induction of EMT. siRNA-mediated knockdown of IDO decreased e-cadherin expression, but had no effect on EMT transcription factors. In the scratch-wound assay, the heightened migration process was intensified when the cells were incubated with MT+TGF-β1. These effects were associated with a robust inhibition of Akt activation. After inoculation of T24 cells under the kidney capsule of Balb/c nude, the cells were positive for IDO in the center of the cell infiltrate, being negative in the periphery, where EMT is high. In conclusion, inhibition of IDO by TGF-β1 and MT is associated with EMT in T24 human bladder carcinoma cells. MT has potentiating effect in TGF-β1-induced EMT, independently of IDO. This nonimmunological effect of MT should be considered if IDO is the target to avoid immune escape in bladder cancer.</p></div