ABSTRACT
The dynamics of changes in albumin transport function during hypochlorite-induced oxidation of isolated albumin in blood plasma and serum was studied with a fluorescent probe K-35. Binding of the probe K-35 to albumin was characterized by effective concentration of albumin. Oxidative modification of proteins was evaluated by the content of carbonyl products of protein oxidation and bityrosine fluorescent products. Oxidation with hypochlorite was accompanied by a decrease in the effective concentration of albumin in albumin, diluted plasma, and serum and accumulation of carbonyl products of protein oxidation and bityrosine fluorescent products. The decrease in the effective concentration of albumin during oxidation with hypochlorite can be explained by oxidative damage to albumin binding sites. Oxidative modification of probe K-35 binding sites with hypochlorite contributes to a decrease in effective concentration of albumin under pathological conditions.
Subject(s)
Hypochlorous Acid/chemistry , Oxidants/chemistry , Serum Albumin/analysis , Binding Sites , Fluorescent Dyes , Humans , Imides , Kinetics , Naphthalenes , Oxidation-Reduction , Protein Binding , Protein Carbonylation , Protein Transport , Serum Albumin/chemistry , Spectrometry, Fluorescence , Tyrosine/analogs & derivatives , Tyrosine/analysisABSTRACT
We studied high-resolution (1)H nuclear magnetic resonance spectra of the serum and serum albumin from patients with the first episode of schizophrenia and healthy individuals. A relative increase in signal intensities of CH(2) protons in serum LDL and VLDL in schizophrenia was demonstrated. Higher intensities of CH(2) and CH(3) protons of non-esterified fatty acids were found in (1)H nuclear magnetic resonance spectra of serum albumin. These data attest to an essential role of changes in lipid metabolism and changed ligand load of albumin in schizophrenia.
Subject(s)
Protons , Schizophrenia/diagnosis , Serum Albumin/chemistry , Adolescent , Adult , Female , Humans , Lipid Metabolism , Lipoproteins, LDL/chemistry , Lipoproteins, LDL/metabolism , Lipoproteins, VLDL/chemistry , Lipoproteins, VLDL/metabolism , Male , Nuclear Magnetic Resonance, Biomolecular , Protein Conformation , Schizophrenia/metabolism , Serum Albumin/metabolismABSTRACT
The state of binding centers in albumin molecule in patients with anxious depression was studied by the method of quenching of fluorescence of molecular probe (dimethyl-aminonaphthaleic acid carboxyphenylimide) with nitrate ions. Serum samples from 24 donors without somatic and mental diseases and 26 patients were analyzed. In the absence of the quenching agent, specific fluorescence of the probe (standardized by albumin concentration) was lower in patients with depression. The fluorescence quenching constant and the percentage of fluorescence available for quenching were also lower in serum samples from patients. These data indicate that the parameters of binding centers in albumin molecule in patients with anxious depression are significantly modified in comparison with normal subjects. The detected changes can play a role in the pathogenesis of depressive disorders.
Subject(s)
Depression/blood , Fluorescence , Serum Albumin/chemistry , Adolescent , Adult , Algorithms , Humans , Kinetics , Middle Aged , Nitrates/chemistry , Potassium Chloride/chemistry , Potassium Compounds/chemistry , Protein Binding , Serum Albumin/metabolismABSTRACT
In this study, the hypothesis was tested that behaviour of rats under the open field test condition and effects of subsequent acute stress relate to conformational properties of the main plasma carrier protein, albumin.To evaluate albumin properties, fluorescence intensity of a molecular probe CAPIDAN (N-carboxyphenylimide of dimethylaminonaphthalic acid) at N (at pH 7.4) and F (at pH 4.2) albumin conformations was measured and the N-F signal ratio was calculated. The data obtained showed that CAPIDAN fluoresces selectively from albumin in rat serum and its fluorescence is sensitive to binding of fatty acids and some other ligands to albumin. Behaviour of 78 Wistar male rats was characterized from the fraction of time taken for exploratory and ambulatory activity during the open field test. In rats not subjected to stress (n = 40), a negative correlation was revealed between open field activity and CAPIDAN N-to-F ratio for albumin (r = - 0.55, p < 0.0005). In the group of rats subjected to acute stress (immobilization plus stochastic electrocutaneous stimulation) the correlation between behavioural activity and the albumin conformational properties was significantly positive (r = 0.59, p < 0.0001): the CAPIDAN albumin fluorescence ratio increased in the highly active rats and decreased in the low-activity rats. The mechanisms of the observed effects may involve differences in nonesterified fatty acid production during stress.
Subject(s)
Exploratory Behavior/physiology , Fatty Acids, Nonesterified/blood , Protein Conformation , Serum Albumin/chemistry , Stress, Psychological/physiopathology , Animals , Binding Sites , Electric Stimulation , Fluorescent Dyes , Imides , Male , Molecular Probes , Motor Activity/physiology , Naphthalenes , Rats , Rats, Wistar , Restraint, PhysicalABSTRACT
This report describes studies of the characteristics of serum albumin in rats with different predicted levels of resistance to emotional stress in control conditions and in conditions of experimental emotional stress. The effects of peptides increasing the resistance of animals to emotional stress (delta sleep-inducing peptide and Semax) on serum albumin were analyzed in rats predicted to be resistant and susceptible to emotional stress.
