ABSTRACT
Selenium is an essential micronutrient for many organisms, and in vertebrates has a variety of roles associated with protection from reactive oxygen species. Over the past two decades there have been conflicting reports upon human health benefits and detriments arising from consumption of selenium dietary supplements. Thus, early studies report a decrease in the incidence of certain types of cancer, whereas subsequent studies did not observe any anti-cancer effect, and adverse effects such as increased risks for type 2 diabetes have been reported. A possible contributing factor may be that different chemical forms of selenium were used in different studies. Using larval stage zebrafish (Danio rerio) as a model organism, we report a comparison of the toxicities and tissue selenium distributions of four different chemical forms of selenium. We find that the organic forms of selenium tested (Se-methyl-l-selenocysteine and l-selenomethionine) show considerably more toxicity than inorganic forms (selenite and selenate), and that this appears to be correlated with the level of bioaccumulation. Despite differences in concentrations, the tissue specific pattern of selenium accumulation was similar for the chemical forms tested; selenium was found to be highly concentrated in pigment (melanin) containing tissues especially for the organic selenium treatments, with lower concentrations in eye lens, yolk sac and heart. These results suggest that pigmented tissues might serve as a storage reservoir for selenium.
Subject(s)
Environmental Exposure , Inorganic Chemicals/toxicity , Organic Chemicals/toxicity , Selenium/metabolism , Zebrafish/metabolism , Animals , Larva/drug effects , Larva/metabolism , Organ Specificity/drug effects , Pigmentation/drug effects , Spectrometry, X-Ray EmissionABSTRACT
The study of HIV-infected patients using new five-color panel CytoDiff for flow cytofluorometry revealed the imbalance in subpopulations of leukocytes. The manifestations consisted in significant decrease of total amount of lymphocytes and also CD16+ lymphocytes. B-lymphocytes and eosinocytes with synchronous increase of level of CD16+ monocytes, neutrophils and immature B-lymphocytes. After application to patients of highly active anti-retroviral therapy occurred decrease of viral load under synchronous increase of total level of lymphocytes, CD16+ lymphocytes, B-lymphocytes and also decrease of amount of CD16+ monocytes, neutrophils and immature B-lymphocytes.
Subject(s)
Flow Cytometry/methods , HIV Infections , Leukocytes/metabolism , Monitoring, Physiologic/methods , Reagent Kits, Diagnostic , Antiretroviral Therapy, Highly Active/methods , Female , HIV Infections/blood , HIV Infections/drug therapy , Humans , Leukocyte Count/methods , Leukocytes/virology , Male , Viral LoadABSTRACT
Immunoprecipitation of Na,K-ATPase from kidney homogenate by antibodies against alpha1-subunit results in the precipitation of several proteins together with the Na,K-ATPase. A protein with molecular mass of about 67 kD interacting with antibodies against melittin (melittin-like protein, MLP) was found in the precipitate when immunoprecipitation was done in the presence of ouabain. If immunoprecipitation was done using antibodies against melittin, MLP and Na,K-ATPase alpha1-subunit were detected in the precipitate, and the amount of alpha1-subunit in the precipitate was increased after the addition of ouabain to the immunoprecipitation medium. MLP was purified from mouse kidney homogenate using immunoaffinity chromatography with antibodies against melittin. The addition of MLP to purified FITC-labeled Na,K-ATPase decreases fluorescence in medium with K+ and increases it in medium with Na+. The enhancement of fluorescence depends upon the MLP concentration. The N-terminal sequence of MLP determined by the Edman method is the following: HPPKRVRSRLNG. No proteins with such N-terminal sequence were found in the protein sequence databases. However, we revealed five amino acid sequences that contain this peptide in the middle part of the chain at distance 553 amino acids from the C-terminus (that corresponds to protein with molecular mass of about 67 kD). Analysis of amino acid sequence located between C-terminus and HPPKRVRSRLNG in all found sequences has shown that they were highly conservative and include WD40 repeats. It is suggested that the 67-kD MLP either belongs to the found protein family or was a product of proteolysis of one of them.
Subject(s)
Antibodies/chemistry , Enzyme Inhibitors/chemistry , Melitten/chemistry , Ouabain/chemistry , Sodium-Potassium-Exchanging ATPase/chemistry , Amino Acid Sequence , Animals , Antibodies/immunology , Catalytic Domain/immunology , Enzyme Inhibitors/pharmacology , Melitten/genetics , Melitten/immunology , Mice , Molecular Weight , Ouabain/pharmacology , Protein Binding/drug effects , Protein Binding/immunology , Rabbits , Rats , Sodium-Potassium-Exchanging ATPase/genetics , Sodium-Potassium-Exchanging ATPase/immunology , SwineABSTRACT
Proteins interacting with alpha 1 beta 1-type of Na,K-ATPase were revealed in pig kidney outer medulla and duck salt glands using three different methods (immunoprecipitation, protein overlay, and chemical cross-linking). Immunoprecipitation was performed after solubilization of protein homogenate with Triton X-100 so that both membrane and cytosol proteins bound to Na,K-ATPase could be revealed. Two other methods were used to study the interaction of cytosol proteins with purified Na,K-ATPase. The sets of proteins revealed by each method in outer medulla of pig kidney were different. Proteins interacting with Na,K-ATPase that have molecular masses 10, 15, 70, 75, 105, 120, and 190 kD were found using the immunoprecipitation method. The chemical cross-linking method revealed proteins with molecular masses 25, 35, 40, 58, 68-70, and 86-88 kD. The protein overlay method revealed in the same tissue proteins with molecular masses 38, 42, 43, 60, 62, 66, 70, and 94 kD.
