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1.
Ann Nutr Metab ; 80(3): 143-152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38471467

RESUMO

INTRODUCTION: Home parenteral nutrition (HPN) is the primary treatment modality for patients with chronic intestinal failure, one of the least common organ failures. This article provides a retrospective analysis of the data collected on HPN patients in the Czech Republic over the past 30 years. METHODS: National registry data were collected using a standardised online form based on the OASIS registry (Oley - A.S.P.E.N. Information System) across all centres providing HPN in the Czech Republic. Data collected prospectively from adult patients in the HPN program were analysed in the following categories: epidemiology, demographics, underlying syndrome, diagnosis, complications, and teduglutide therapy prevalence. RESULTS: The registry identified a total of 1,838 adult patient records, reflecting almost 1.5 million individual catheter days. The prevalence of HPN has risen considerably over the last few decades, currently reaching 5.5 per 100,000 population. The majority of patients have short bowel syndrome and GI obstruction, with cancer being the most prevalent underlying disease. Catheter-related bloodstream infections have been the most prevalent acute complication. However, the incidence in 2022 was only 0.15 per 1,000 catheter days. The study also observed an increase in the prevalence of patients on palliative HPN over the last decade. CONCLUSION: This study presents a thorough analysis of data from the Czech REgistr Domaci NUtricni Podpory (REDNUP) registry. It shows an increasing prevalence of HPN, namely, in the palliative patient group. The sharing of national data can improve understanding of this rare condition and facilitate the development of international guidelines.


Assuntos
Nutrição Parenteral no Domicílio , Sistema de Registros , Humanos , Nutrição Parenteral no Domicílio/estatística & dados numéricos , República Tcheca/epidemiologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Insuficiência Intestinal/terapia , Insuficiência Intestinal/epidemiologia , Prevalência , Síndrome do Intestino Curto/terapia , Infecções Relacionadas a Cateter/epidemiologia , Peptídeos/administração & dosagem , Adulto Jovem
2.
Nutrients ; 16(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38398809

RESUMO

(1) Objectives: Intestinal failure in home parenteral nutrition patients (HPNPs) results in oxidative stress and liver damage. This study investigated how a high dose of fish oil (FO) added to various lipid emulsions influences antioxidant status and liver function markers in HPNPs. (2) Methods: Twelve HPNPs receiving Smoflipid for at least 3 months were given FO (Omegaven) for a further 4 weeks. Then, the patients were randomized to subsequently receive Lipoplus and ClinOleic for 6 weeks or vice versa plus 4 weeks of Omegaven after each cycle in a crossover design. Twelve age- and sex-matched healthy controls (HCs) were included. (3) Results: Superoxide dismutase (SOD1) activity and oxidized-low-density lipoprotein concentration were higher in all baseline HPN regimens compared to HCs. The Omegaven lowered SOD1 compared to baseline regimens and thus normalized it toward HCs. Lower paraoxonase 1 activity and fibroblast growth factor 19 (FGF19) concentration and, on the converse, higher alkaline phosphatase activity and cholesten concentration were observed in all baseline regimens compared to HCs. A close correlation was observed between FGF19 and SOD1 in baseline regimens. (4) Conclusions: An escalated dose of FO normalized SOD1 activity in HPNPs toward that of HCs. Bile acid metabolism was altered in HPNPs without signs of significant cholestasis and not affected by Omegaven.


Assuntos
Colestase , Nutrição Parenteral no Domicílio , Humanos , Superóxido Dismutase-1 , Emulsões Gordurosas Intravenosas , Óleos de Peixe , Óleo de Soja , Nutrição Parenteral no Domicílio/métodos
3.
Nutrients ; 12(8)2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32781598

RESUMO

Omega-3 polyunsaturated fatty acids (ω-3PUFAs) are introduced into parenteral nutrition (PN) as hepatoprotective but may be susceptible to the lipid peroxidation while olive oil (OO) is declared more peroxidation resistant. We aimed to estimate how the lipid composition of PN mixture affects plasma and erythrocyte lipidome and the propensity of oxidative stress. A cross-sectional comparative study was performed in a cohort of adult patients who were long-term parenterally administered ω-3 PUFAs without (FO/-, n = 9) or with (FO/OO, n = 13) olive oil and healthy age- and sex-matched controls, (n = 30). Lipoperoxidation assessed as plasma and erythrocyte malondialdehyde content was increased in both FO/- and FO/OO groups but protein oxidative stress (protein carbonyls in plasma) and low redox status (GSH/GSSG in erythrocytes) was detected only in the FO/- subcohort. The lipidome of all subjects receiving ω-3 PUFAs was enriched with lipid species containing ω-3 PUFAs (FO/-˃FO/OO). Common characteristic of all PN-dependent patients was high content of fatty acyl-esters of hydroxy-fatty acids (FAHFAs) in plasma while acylcarnitines and ceramides were enriched in erythrocytes. Plasma and erythrocyte concentrations of plasmanyls and plasmalogens (endogenous antioxidants) were decreased in both patient groups with a significantly more pronounced effect in FO/-. We confirmed the protective effect of OO in PN mixtures containing ω-3 PUFAs.


Assuntos
Antioxidantes/metabolismo , Emulsões Gordurosas Intravenosas/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Nutrição Parenteral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Eritrócitos/metabolismo , Feminino , Óleos de Peixe/farmacologia , Humanos , Enteropatias/sangue , Enteropatias/terapia , Lipidômica , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Azeite de Oliva/farmacologia , Nutrição Parenteral/efeitos adversos
4.
Environ Sci Pollut Res Int ; 27(16): 20344-20357, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32239414

RESUMO

The composition of lipids in soil offers clues to soil degradation processes due their persistency and selectivity in soil, and close relation to long-term processes in the ecosystem, thanks to their role in cell membranes of organisms. Organic solvent-extractable compounds were recovered from soils collected at two sites differing in the degree of forest damage. Gas chromatography/mass spectroscopy and Fourier transform infrared spectroscopy were applied in order to characterize solvent-extractable lipids. Raman spectroscopy was also applied as it provides distinct advantages for determining the structural order of carbonaceous materials. The organic matter measurement techniques were combined with an established simultaneous multi-element measurement technique. Variations in individual soil horizons from the sites were reflected in the crystallinity of epicuticular waxes, presence of long-chain aliphatic hydrocarbons, concentrations of n-alkanes, saturated and unsaturated fatty acids, dicarboxylic acids, and in the content of aromatic structures, hydroxyl, ester, and carboxylic acid groups. The results are explained by differently transformed organic matter. The concentrations of elements in the soils were also affected by atmospheric depositions, including higher accumulations of arsenic and antimony, and lower contents of natural nutrients. These data have potential to be used as sensitive biogenic indicators of ecosystem damage by long-term atmospheric depositions.


Assuntos
Ecossistema , Solo , República Tcheca , Florestas , Polônia
5.
Nutr Res ; 72: 70-79, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31759770

RESUMO

Long-chain n-3 polyunsaturated fatty acids modulate immune cell functions. The primary objective of this study was to evaluate the impact of different lipid emulsions (LEs) with supplemented doses of fish oil (FO) on serum cytokine concentration and in vitro cytokine production in patients with intestinal failure on home parenteral nutrition (HPNPs). We hypothesized that FO supplementation would diminish lipopolysaccharide (LPS)-stimulated cytokine production. Twelve HPNPs receiving Smoflipid for at least 3 months were given FO (Omegaven) for a further 4 weeks. After this cycle, the patients were randomized to subsequently receive 1 cycle with Lipoplus and 1 cycle with ClinOleic for 6 weeks or vice versa plus 4 weeks of added Omegaven after each cycle in a crossover design. Comparison of the baseline LE regimens showed lower LPS-stimulated production of IL-1ß in the HPNPs on Lipoplus than on the Smoflipid and ClinOleic regimens, as well as lower IL-8 compared to the Smoflipid regimen. Omegaven reduced IL-8 concentration in serum under the Lipoplus regimen and diminished LPS-stimulated production of IL-1ß under the Smoflipid and ClinOleic. IL-6 and TNF-α production was depressed only in those on Smoflipid. Irrespective of the LE used, the HPNPs compared to the healthy controls showed higher IL-6, IL-8, and TNF-α concentrations in serum and LPS-stimulated production of IL-6 as well as lower n-6/n-3 long-chain polyunsaturated fatty acids in the erythrocyte phospholipids. LPS-stimulated production of IL-6 correlated negatively with the parenteral dose of eicosapentaenoic acid + docosahexaenoic acid. In conclusion, FO-supplemented parenteral nutrition suppresses in vitro cytokine production.


Assuntos
Citocinas/sangue , Emulsões Gordurosas Intravenosas/farmacologia , Óleos de Peixe/farmacologia , Nutrição Parenteral no Domicílio/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Suplementos Nutricionais , Emulsões Gordurosas Intravenosas/administração & dosagem , Emulsões Gordurosas Intravenosas/metabolismo , Feminino , Óleos de Peixe/administração & dosagem , Óleos de Peixe/sangue , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade
6.
Vnitr Lek ; 65(3): 219-226, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31088099

RESUMO

Recent research of nutrition in the acute phase has brought up important findings regarding high protein and energy administration in critical illness with suggested adverse outcomes in catabolic patients. On the other hand, refeeding hypophosphatemia and refeeding syndrome may also be common during acute illness especially in chronically malnourished patients. Moreover, enteral nutrition is no longer superior to parenteral nutrition in recent studies as signals of harm using the enteral route in shock have been suggested. A consensus scheme for diagnosing malnutrition in adults in clinical settings on a global scale has been proposed. Nutrition screening, assessment and intervention guidelines in intensive care and in chronic polymorbid internal patients has recently been published. These new findings and guidelines will probably change the practice of metabolic and nutrition therapy in acute illness and subsequent recovery.


Assuntos
Estado Terminal , Nutrição Enteral , Estado Nutricional , Doença Aguda , Adulto , Humanos , Apoio Nutricional , Nutrição Parenteral
7.
Ecotoxicol Environ Saf ; 167: 422-428, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30368135

RESUMO

Physical and chemical structure affect properties of dissolved organic matter (DOM). Recent observations revealed that heating and cooling cycles at higher temperature amplitude lead to a change in DOM physical conformation assumingly followed by a slow structural relaxation. In this study, changes at lower temperature amplitudes and their relation to DOM composition were investigated using simultaneous measurements of density and ultrasonic velocity in order to evaluate the adiabatic compressibility, which is sensitive indicator of DOM structural microelasticity. Six fulvic acids (FAs) having various origins were analyzed at concentrations of 0.12, 0.6 and 1.2 g L-1 and at different temperature amplitudes. First, we validated that the used technique is sensitive to distinguish conclusively the structural changes upon heating and cooling of DOM with heating/cooling amplitude of ±â€¯3 °C and higher. This amplitude was then applied to observe the relationship between change in adiabatic compressibility and chemical composition of FA. No correlation was observed with elemental composition and aromatic structures. Positive correlations were observed with content of alkyl moieties, carboxylic and carbonyl carbons and biological activity. Based on literature data, it was concluded that alkyl moieties undergo (re)crystalization during thermal fluctuation and their structural relaxation back is very slow (if occurs). The polar moieties form a flexible hydrogel responding to thermal fluctuation by moderate dissolution and re-aggregation. Negative correlation was observed in relation to the amount of peptide and O-alkyl systems, which can be attributed to very fast structural relaxation of proteinaceous materials, i.e. their larger content leads to lower difference between original and heat-induced compressibility. Last, the increase of the heating/cooling amplitude from ±â€¯3 to ±â€¯15 °C resulted in an increase of the change of the adiabatic compressibility and in the extension of the relaxation time needed for DOM structure to return to the equilibrium. We conclude that this increase is caused by the increase in inner energy, and DOM conformation can reach a cascade of energy minima, which may influence DOM reactivity and biodegradability.


Assuntos
Benzopiranos/química , Conformação Molecular , Compostos Orgânicos/química , Temperatura , Benzopiranos/análise , Biodegradação Ambiental , Carbono , Cristalização
8.
Lipids ; 52(3): 245-254, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28039586

RESUMO

This study analyzes fatty acid (FA) composition in plasma lipids and erythrocyte phospholipids while comparing septic and non-septic critically ill patients. The aim was to describe impacts of infection and the inflammatory process. Patients with severe sepsis (SP, n = 13); age-, sex- and APACHE II score-matched non-septic critically ill with systemic inflammatory response syndrome (NSP, n = 13); and age-/sex-matched healthy controls (HC, n = 13) were included in a prospective case-control study during the first 24 h after admission to the intensive care unit. In both SP and NSP, lower n-6 polyunsaturated FA (PUFA) accompanied by higher proportions of monounsaturated FA (MUFA) in plasma phospholipids (PPL) was observed relative to HC. MUFA proportion was negatively correlated with n-6 PUFA, high density lipoprotein cholesterol (HDL-C), and albumin. MUFA was positively correlated with C-reactive protein (CRP), procalcitonin (PCT), interleukins (IL-6, IL-10), oxidized low density lipoproteins (ox-LDL), and conjugated dienes (CD). In both SP and NSP, inflammatory and lipid peroxidation markers were significantly higher-CRP (p < 0.001; p = 0.08), IL-6, IL-10, TNF-α (p < 0.01, p = 0.06), ox-LDL, and CD while total cholesterol, HDL-C, LDL-C albumin, and 20:4n-6/22:6n-3 and n-6/n-3 ratios were lower compared to HC. In conclusion, the changes in plasma lipid FA profile relate to the intensity of inflammatory and peroxidative response regardless of insult etiology. The lower MUFA and higher n-6 PUFA proportions in PPL were inversely correlated with cholesterol and albumin levels.


Assuntos
Biomarcadores/sangue , Estado Terminal , Ácidos Graxos/sangue , Fosfolipídeos/sangue , Sepse/imunologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Idoso , Proteína C-Reativa/metabolismo , Calcitonina/metabolismo , Estudos de Casos e Controles , Ácidos Graxos Monoinsaturados/sangue , Feminino , Humanos , Interleucinas/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sepse/metabolismo
9.
Ann Nutr Metab ; 69(2): 120-124, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27736814

RESUMO

BACKGROUND: The objective of the present study was to determine concentrations of zinc (Zn), copper (Cu), iron (Fe), selenium (Se) in blood plasma and manganese (Mn) in the whole blood in patients with long-term home parenteral nutrition (HPN) in comparison to the control group. PATIENTS AND METHODS: We examined 68 patients (16 men and 52 women) aged from 28 to 68 years on a long-term HPN lasting from 4 to 96 months. The short bowel syndrome was an indication for HPN. The daily doses of Zn, Cu, Fe, Se and Mn in the last 3 months were determined. RESULTS: No significant differences in blood plasma were found for Zn, Cu and Fe in patients with HPN and in the control group (p > 0.05). The concentration of Mn in whole blood was significantly increased in HPN patients (p < 0.0001), while Se concentration in these patients was significantly decreased (p < 0.005). The concentration of Mn in the whole blood of 16 patients with cholestasis was significantly increased compared to the patients without cholestasis (p < 0.001). The Cu concentration was increased with no statistical significance. CONCLUSION: In long-term HPN, the status of trace elements in the patients has to be continually monitored and the daily substitution doses of these elements have to be flexibly adjusted. Dosing schedule needs to be adjusted especially in cases of cholestatic hepatopathy. A discussion about the optimal daily dose of Mn in patients on HPN is appropriate. For clinical practice, the availability of a substitution mixture of trace elements lacking Mn would be advantageous.


Assuntos
Deficiências Nutricionais/prevenção & controle , Estado Nutricional , Nutrição Parenteral no Domicílio/efeitos adversos , Síndrome do Intestino Curto/terapia , Oligoelementos/deficiência , Adulto , Idoso , Colestase Intra-Hepática/complicações , Cobre/análise , Cobre/sangue , Cobre/deficiência , Cobre/uso terapêutico , República Tcheca/epidemiologia , Deficiências Nutricionais/epidemiologia , Deficiências Nutricionais/etiologia , Feminino , Humanos , Ferro/análise , Ferro/sangue , Ferro/uso terapêutico , Deficiências de Ferro , Masculino , Manganês/análise , Manganês/sangue , Manganês/deficiência , Manganês/uso terapêutico , Pessoa de Meia-Idade , Soluções de Nutrição Parenteral/química , Prevalência , Risco , Selênio/análise , Selênio/sangue , Selênio/deficiência , Selênio/uso terapêutico , Síndrome do Intestino Curto/sangue , Síndrome do Intestino Curto/complicações , Síndrome do Intestino Curto/fisiopatologia , Fatores de Tempo , Oligoelementos/análise , Oligoelementos/sangue , Oligoelementos/uso terapêutico , Zinco/análise , Zinco/sangue , Zinco/deficiência , Zinco/uso terapêutico
10.
Cas Lek Cesk ; 155(2): 34-40, 2016.
Artigo em Tcheco | MEDLINE | ID: mdl-27088791

RESUMO

Despite being known more than 60 years, refeeding syndrome (RS) still bears many uncertainties. For example, its definition is not clear and definite, and the attitude to it varies from the complete neglect to over-prevention.The term "refeeding syndrome" refers to electrolyte and metabolic changes occurring in malnourished patients after the readministration of nutrition. These changes concern especially to phosphates and ions. Potassium, magnesium, naturism and fluids balance are involved. The changes lead to cell energetic metabolism and electric potential disturbances, with related clinical symptoms.Fully developed refeeding syndrome is quite rare; nevertheless it can be fatal for the patient. However, even its development can lead to many complications increasing the patient's morbidity and the length of stay in the hospital. Yet the refeeding syndrome is more or less predictable and if kept in mind also preventable.The aim of this article is to get the reader to know more about this metabolic phenomenon and possible attitudes towards it.


Assuntos
Estado Nutricional , Síndrome da Realimentação/diagnóstico , Síndrome da Realimentação/etiologia , Desequilíbrio Hidroeletrolítico/fisiopatologia , Humanos , Hipofosfatemia/etiologia , Hipofosfatemia/fisiopatologia , Deficiência de Magnésio/etiologia , Deficiência de Magnésio/fisiopatologia , Síndrome da Realimentação/prevenção & controle , Desequilíbrio Hidroeletrolítico/etiologia
11.
Clin Exp Med ; 16(4): 557-569, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26416404

RESUMO

Markers of oxidative stress and antioxidant status in relation to inflammatory mediators in septic patients (SPs) during the course of sepsis and after recovery were analysed. Patients were 30 critically ill adults in severe sepsis/septic shock, 19 of which completed 3 samplings (S1: within 24 h after onset of sepsis, S7: 7 days after S1, R7: 7 days after clinical recovery). Comparing SPs with healthy controls (HCs), enhanced C-reactive protein, procalcitonin, bilirubin and CuZn-superoxide dismutase activity were found at S1 only. Oxidized low-density lipoprotein, conjugated dienes and nitrotyrosine were increased at S1, culminated at S7 and reverted nearly to HC levels at R7. Reduced catalase activity and serum amyloid were observed at S1 and endured until R7. Increase in IL-6, IL-10 and tumour necrosis factor alpha (TNF-α) with accompanying decrease in apolipoprotein A1, high-density lipoprotein (HDL) cholesterol, selenium, zinc, albumin, paraoxonase 1 and glutathione peroxidase 1 activity appeared at S1 and persisted until R7. TNF-α, IL-10 and markers of oxidative stress were in negative correlation with HDL cholesterol and albumin at R7. After clinical recovery, increased cytokines and decreased antioxidants were accompanied by lower albumin and HDL cholesterol levels. During this important and beneficial period of tissue repair, patients with prolonged persistence of this status are probably more vulnerable to secondary infections and should be dealt with as constituting a high-risk population.


Assuntos
HDL-Colesterol/sangue , Citocinas/sangue , Sepse/metabolismo , Albumina Sérica/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Estudos Prospectivos , Sepse/imunologia
12.
ScientificWorldJournal ; 2014: 642427, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24672346

RESUMO

Possible enhancement of biodegradation of petroleum hydrocarbons in agricultural soil after tank truck accident (~5000 mg/kg dry soil initial concentration) by bioaugmentation of diesel degrading Pseudomonas fluorescens strain and addition of abiotic additives (humates, zeolite) was studied in a 9-month pot experiment. The biodegradation process was followed by means of analytical parameters (hydrocarbon index expressed as content of C10-C40 aliphatic hydrocarbons, ratio pristane/C17, and total organic carbon content) and characterization of soil microbial community (content of phospholipid fatty acids (PLFA) as an indicator of living microbial biomass, respiration, and dehydrogenase activity). The concentration of petroleum hydrocarbons (C10-C40) was successfully reduced by ~60% in all 15 experiment variants. The bioaugmentation resulted in faster hydrocarbon elimination. On the contrary, the addition of humates and zeolite caused only a negligible increase in the degradation rate. These factors, however, affected significantly the amount of PLFA. The humates caused significantly faster increase of the total PLFA suggesting improvement of the soil microenvironment. Zeolite caused significantly slower increase of the total PLFA; nevertheless it aided in homogenization of the soil. Comparison of microbial activities and total PLFA revealed that only a small fraction of autochthonous microbes took part in the biodegradation which confirms that bioaugmentation was the most important treatment.


Assuntos
Agricultura , Biodegradação Ambiental , Gasolina , Solo , Zeolitas/química , Humanos , Cinética , Microbiologia do Solo
13.
Curr Pharm Des ; 19(39): 6880-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23590154

RESUMO

The purpose of the present study was to assess the impact of brief daily reoxygenation during adaptation to chronic continuous hypoxia (CCH) on protective cardiac phenotype. Adult male Wistar rats were kept at CCH (10% oxygen) for 5, 15 or 30 days; a subgroup of animals was exposed to room air daily for a single 60-min period. While 5 days of CCH did not affect myocardial infarction induced by 20-min coronary artery occlusion and 3-h reperfusion, 15 days reduced infarct size from 62% of the area at risk in normoxic controls to 52%, and this protective effect was more pronounced after 30 days (41%). Susceptibility to ischemic ventricular arrhythmias exhibited reciprocal development. CCH increased myocardial abundance of mitochondrial superoxide dismutase (MnSOD) without affecting malondialdehyde concentration. Daily reoxygenation abolished both the infarct size-limiting effect of CCH and MnSOD upregulation, and increased malondialdehyde (by 53%). Ventricular cardiomyocytes isolated from CCH rats exhibited better survival and lower lactate dehydrogenase release caused by simulated ischemia/reperfusion than cells from normoxic and daily reoxygenated groups. The cytoprotective effects of CCH were attenuated by the large-conductance Ca2+-activated K+ (BKCa) channel blocker paxilline, while the opener NS1619 reduced cell injury in the normoxic group but not in the CCH group. Daily reoxygenation restored the NS1619- induced protection, whereas paxilline had no effect, resembling the pattern observed in the normoxic group. The results suggest that CCH is cardioprotective and brief daily reoxygenation blunts its salutary effects, possibly by a mechanism involving oxidative stress and attenuation of the activation of mitochondrial BKCa channels.


Assuntos
Cardiotônicos/farmacologia , Hipóxia/metabolismo , Estresse Oxidativo , Oxigênio/metabolismo , Canais de Potássio/metabolismo , Animais , Glicosilação , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
14.
Chemosphere ; 90(2): 789-95, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23089388

RESUMO

Humic substances play an important role in many environmental processes such as sequestration and transport of hydrophobic compounds. The supramolecular character of humic substances imparts high flexibility of the aggregates associated with their variable reactivity under different conditions. In this study, heat-induced transitions and character of the hydration shell of sodium salts of humic and fulvic acids originating from various sources were investigated using ultrasonic velocimetry in the temperature interval from 5 to 90 °C. Results clearly showed differences in stability and characteristics of the hydrated states at concentrations above and below 1 g L(-1) with the exception of Pahokee peat fulvic acids. It has been concluded that predominantly the relaxation part of the adiabatic compressibility plays an important role below 1 g L(-1) in contrast to both relaxation and intrinsic parts of the compressibility being important at higher concentrations. Dilution brought several temperature induced transitions which were investigated with respect to composition of all investigated humic substances. Correlation analysis revealed that the transition around 17 °C is associated with disruption of H-interactions whereas the transition around 42 °C depends on the aromaticity. Comparison of cooling and heating records revealed hysteresis in the structural relaxation resembling the behavior of physically stabilized hydrogels. Results indicated a difference in the conformation and therefore reactivity of dissolved humic substances in the dependence on temperature and thermal history. It has been hypothesized that this may play an important role in the transport and sequestration of hydrophobic pollutants by dissolved organic matter.


Assuntos
Benzopiranos/química , Temperatura Alta , Poluentes do Solo/química , Solo/química , Substâncias Húmicas/análise , Interações Hidrofóbicas e Hidrofílicas , Modelos Químicos , Poluentes do Solo/análise
15.
Physiol Genomics ; 44(2): 173-82, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22128087

RESUMO

CD36 fatty acid translocase plays a key role in supplying heart with its major energy substrate, long-chain fatty acids (FA). Previously, we found that the spontaneously hypertensive rat (SHR) harbors a deletion variant of Cd36 gene that results in reduced transport of long-chain FA into cardiomyocytes and predisposes the SHR to cardiac hypertrophy. In the current study, we analyzed the effects of mutant Cd36 on susceptibility to ischemic ventricular arrhythmias and myocardial infarction in adult SHR-Cd36 transgenic rats with wild-type Cd36 compared with age-matched SHR controls. Using an open-chest model of coronary artery occlusion, we found that SHR-Cd36 transgenic rats showed profound arrhythmogenesis resulting in significantly increased duration of tachyarrhythmias (207 ± 48 s vs. 55 ± 21 s, P < 0.05), total number of premature ventricular complexes (2,623 ± 517 vs. 849 ± 250, P < 0.05) and arrhythmia score (3.86 ± 0.18 vs. 3.13 ± 0.13, P < 0.001). On the other hand, transgenic SHR compared with SHR controls showed significantly reduced infarct size (52.6 ± 4.3% vs. 72.4 ± 2.9% of area at risk, P < 0.001). Similar differences were observed in isolated perfused hearts, and the increased susceptibility of transgenic SHR to arrhythmias was abolished by reserpine, suggesting the involvement of catecholamines. To further search for possible molecular mechanisms of altered ischemic tolerance, we compared gene expression profiles in left ventricles dissected from 6-wk-old transgenic SHR vs. age-matched controls using Illumina-based sequencing. Circadian rhythms and oxidative phosphorylation were identified as the top KEGG pathways, while circadian rhythms, VDR/RXR activation, IGF1 signaling, and HMGB1 signaling were the top IPA canonical pathways potentially important for Cd36-mediated effects on ischemic tolerance. It can be concluded that transgenic expression of Cd36 plays an important role in modulating the incidence and severity of ischemic and reperfusion ventricular arrhythmias and myocardial infarct size induced by coronary artery occlusion. The proarrhythmic effect of Cd36 transgene appears to be dependent on adrenergic stimulation.


Assuntos
Arritmias Cardíacas/genética , Antígenos CD36/genética , Perfilação da Expressão Gênica , Infarto do Miocárdio/genética , Animais , Arritmias Cardíacas/metabolismo , Pressão Sanguínea , Antígenos CD36/metabolismo , Predisposição Genética para Doença , Masculino , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Ratos , Ratos Endogâmicos SHR
16.
Mol Cell Biochem ; 357(1-2): 163-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21625957

RESUMO

Disruption to the sensitive balance of long-chain fatty acids and glucose in the heart could cause cardiovascular diseases. Searching for a possible role of novel protein kinase C (nPKC) in heart with disrupted energy balance, we compared the insulin-resistant spontaneously hypertensive rats (SHR), which carry a nonfunctional variant of the fatty acid transporter FAT/CD36, with the less insulin-resistant congenic strain SHR-4 that is genetically identical except for a segment on chromosome 4 including a wild-type gene for a functional FAT/CD36. We analyzed expression of the nPKC-δ and -ε isoforms plus triacylglycerols (TAG) content in the myocardium of both FAT/CD36 strains and after a high sucrose diet (HSD). Two weeks before killing, males of both strains were randomly divided into two groups and fed either a standard laboratory chow or an HSD. PKC was determined by Western blotting in particulate and cytosolic fractions from left ventricles. The SHR-4 rats exhibited lower serum levels of insulin and free fatty acids than did SHR rats and higher amounts of PKC-ε in the heart particulate fraction. HSD caused accumulation of heart TAG in SHR but not in SHR-4. HSD increased PKC-δ and decreased PKC-ε expression in particulate fraction from left ventricles of SHR-4 while having no effects in SHR. These results demonstrate that reduced insulin resistance in SHR-4 rats with wild-type FAT/CD36 is associated with the insulin signaling pathway involving nPKCs.


Assuntos
Antígenos CD36/metabolismo , Ventrículos do Coração/metabolismo , Resistência à Insulina/genética , Proteína Quinase C-delta/biossíntese , Proteína Quinase C-épsilon/biossíntese , Animais , Glicemia/análise , Glicemia/metabolismo , Antígenos CD36/genética , Citosol/metabolismo , Ativação Enzimática , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Regulação da Expressão Gênica , Insulina/sangue , Insulina/metabolismo , Resistência à Insulina/fisiologia , Masculino , Miocárdio/metabolismo , Ratos , Ratos Endogâmicos SHR , Transdução de Sinais , Sacarose/metabolismo , Triglicerídeos/sangue , Triglicerídeos/metabolismo
17.
Cas Lek Cesk ; 149(7): 324-31, 2010.
Artigo em Tcheco | MEDLINE | ID: mdl-20925276

RESUMO

BACKGROUND: The overall fatty acid (FA) composition, and especially proportions of n-6 and n-3 polyunsaturated fatty acids in plasma and membrane lipids, greatly impacts on cell and organ functions as well as on many biological processes. MATERIAL AND METHODS: Polyunsaturated FA determine membrane fluidity and thus modulate activities of membrane proteins (enzymes, carriers and receptors). They also are precursors of pro- and anti-inflammatory eicosanoids and other autacoids (resolvins, protectins). Thus, alterations in lipid FA composition of critically ill patients affect reactivity of the organism to numerous pathological stimuli. The objective of this study was to analyse FA composition of plasma triacylglycerols, cholesteryl esters, plasma phospholipids and erythrocyte phospholipids in septic patients. RESULTS: The study group consisted of 30 septic patients, 19 of whom were available for three samplings: Sampling 1 was 24 hours after the onset of sepsis, Sampling 2 was 7 days after Sampling 1, and Sampling 3 was 7 days after recovery from sepsis. Eight septic patients died. Compared to healthy controls, a decrease in n-6 polyunsaturated fatty acids accompanied by increase in monounsaturated fatty acids in cholesteryl esters, plasma phospholipids and erythrocyte phospholipids persisted in all three samplings of septic patients. CONCLUSIONS: This effect of sepsis was significantly greater in cholesteryl esters and plasma phospholipids of non-surviving septic patients than in surviving ones. Moreover, non-survivors had lower proportions of n-3 polyunsaturated fatty acids in plasma phospholipids compared to survivors. The significant decrease in proportion of polyunsaturated fatty acids in lipids of septic patients in the course of sepsis reflects the severity of their critical state and supports the importance of appropriate nutritional polyunsaturated fatty acids supplementation.


Assuntos
Eritrócitos/metabolismo , Ácidos Graxos/sangue , Plasma/metabolismo , Sepse/sangue , Idoso , Estado Terminal , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Sepse/mortalidade , Taxa de Sobrevida
18.
Mol Cell Biochem ; 345(1-2): 271-82, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20853175

RESUMO

The adaptation to chronic hypoxia confers long-lasting cardiac protection against acute ischemia-reperfusion injury. Protein kinase C (PKC) appears to play a role in the cardioprotective mechanism but the involvement of individual PKC isoforms remains unclear. The aim of this study was to examine the effects of chronic intermittent hypoxia (CIH; 7,000 m, 8 h/day) and acute administration of PKC-δ inhibitor (rottlerin, 0.3 mg/kg) on the expression and subcellular distribution of PKC-δ and PKC-ε in the left ventricular myocardium of adult male Wistar rats by Western blot and quantitative immunofluorescence microscopy. CIH decreased the total level of PKC-ε in homogenate without affecting the level of phosphorylated PKC-ε (Ser729). In contrast, CIH up-regulated the total level of PKC-δ as well as the level of phosphorylated PKC-δ (Ser643) in homogenate. Rottlerin partially reversed the hypoxia-induced increase in PKC-δ in the mitochondrial fraction. Immunofluorescent staining of ventricular cryo-sections revealed increased co-localization of PKC-δ with mitochondrial and sarcolemmal membranes in CIH hearts that was suppressed by rottlerin. The formation of nitrotyrosine as a marker of oxidative stress was enhanced in CIH myocardium, particularly in mitochondria. The expression of total oxidative phosphorylation complexes was slightly decreased by CIH mainly due to complex II decline. In conclusion, up-regulated PKC-δ in CIH hearts is mainly localized to mitochondrial and sarcolemmal membranes. The inhibitory effects of rottlerin on PKC-δ subcellular redistribution and cardioprotection (as shown previously) support the view that this isoform plays a role in the mechanism of CIH-induced ischemic tolerance.


Assuntos
Hipóxia/enzimologia , Miocárdio/patologia , Proteína Quinase C-delta/fisiologia , Regulação para Cima , Animais , Doença Crônica , Mitocôndrias/metabolismo , Miocárdio/metabolismo , Fosforilação , Substâncias Protetoras , Proteína Quinase C-delta/genética , Proteína Quinase C-delta/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Wistar , Sarcolema/metabolismo , Distribuição Tecidual
19.
Clin Exp Med ; 10(1): 21-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19760042

RESUMO

Paraoxonase 1 is believed to play a role in preventing lipid oxidation and, thus, limiting production of proinflammatory mediators. Systemic inflammatory response in sepsis increases oxidative stress and decreases high-density lipoprotein (HDL) concentrations. The objective of this study was to investigate serum paraoxonase 1 activities in critically ill patients with sepsis and after recovery. Serum paraoxonase 1 arylesterase/paraoxonase activities, concentration of total cholesterol, HDL cholesterol (HDL-C) and serum C-reactive protein (CRP) in septic patients of a medical intensive care unit (n = 30) and age/sex-matched outpatient controls without sepsis (n = 30) were analyzed. Paired convalescent samples were also taken 1 week after recovery (n = 11). In septic patients, both arylesterase (88.3 +/- 36.5 vs. 162.1 +/- 44.8 kU/l, P < 0.001) and paraoxonase (75.2 +/- 50.0 vs. 125.2 +/- 69.4 U/l, P < 0.01) paraoxonase 1 activities decreased as compared to controls. Both activities normalized after recovery. Negative correlation was found between CRP and both arylesterase (r = -0.676, P < 0.001) and paraoxonase (r = -0.401, P < 0.01) as well as positive correlation between HDL-C and both arylesterase (r = 0.585, P < 0.001) and paraoxonase (r = 0.405, P < 0.01) paraoxonase 1 activities. The decreased activity of paraoxonase 1 in negative correlation with CRP offers a potentially useful marker of sepsis progress and recovery in critically ill patients.


Assuntos
Arildialquilfosfatase/sangue , Estado Terminal , Sepse/diagnóstico , Sepse/patologia , Adulto , Idoso , Biomarcadores , Proteína C-Reativa/análise , Colesterol/sangue , HDL-Colesterol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Br J Nutr ; 102(9): 1297-307, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19480730

RESUMO

The effects of dietary supplementation with fat of different fatty acid profile and chronic intermittent hypoxia (CIH) on the fatty acid composition of serum and heart lipids were analysed. Adult male Wistar rats were fed a standard non-fat diet enriched with 10 % of lard, fish oil (n-3 PUFA) or maize oil (n-6 PUFA) for 10 weeks. After 4 weeks on the diets, each group was divided in two subgroups, either exposed to CIH in a barochamber (7000 m, twenty-five exposures) or kept at normoxia. In normoxic rats, the fish oil diet increased the level of conjugated dienes. The n-6:n-3 PUFA ratio in serum TAG, phospholipids (PL), cholesteryl esters (CE) and heart TAG, PL and diacylglycerols (DAG) followed the ratio in the fed diet (in the sequence maize oil>lard>fish oil). In heart TAG, PL and DAG, 20 : 4n-6 and 18 : 2n-6 were replaced by 22 : 6n-3 in the fish oil group. The main fatty acid in CE was 20 : 4n-6 in the lard and maize oil groups whereas in the fish oil group, half of 20 : 4n-6 was replaced by 20 : 5n-3. CIH further increased 20 : 5n-3 in CE in the fish oil group. CIH decreased the n-6:n-3 PUFA ratio in serum CE, heart TAG, PL and DAG in all dietary groups and stimulated the activity of catalase in the maize and fish oil groups. In conclusion, PUFA diets and CIH, both interventions considered to be cardioprotective, distinctly modified the fatty acid profile in serum and heart lipids with specific effects on conjugated diene production and catalase activity.


Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Insaturados/farmacologia , Hipóxia/fisiopatologia , Peroxidação de Lipídeos/efeitos dos fármacos , Miocárdio/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/fisiologia , Animais , Cardiotônicos/farmacologia , Catalase/metabolismo , Doença Crônica , Óleo de Milho/farmacologia , Gorduras na Dieta/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Ômega-6/farmacologia , Ácidos Graxos Insaturados/análise , Óleos de Peixe/farmacologia , Lipídeos/sangue , Masculino , Ratos , Ratos Wistar
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