RESUMO
Kluyveromyces lactis is broadly considered as a safe yeast in food and a suitable organism for the production of food enzymes. The K. lactis enzyme production strains of DSM are used to produce a variety of enzymes, for example beta-galactosidase (lactase), chymosin and esterase. All of these production strains are derived from the same lineage, meaning they all originate from the same ancestor strain after classical mutagenesis and/or genetic engineering. Four different enzyme preparations produced with strains within this lineage were toxicologically tested. These enzyme preparations were nontoxic in repeated-dose oral toxicity studies performed in rats and were non-genotoxic in vitro. These studies confirm the safety of the DSM K. lactis strains as a production platform for food enzymes, as well as the safety of the genetic modifications made to these strains through genetic engineering or classical mutagenesis. The outcome of the toxicity studies can be extended to other enzyme preparations produced by any strain from this lineage through read across. Therefore, no new toxicity studies are required for the safety evaluation, as long as the modifications made do not raise safety concerns. Consequently, this approach is in line with the public ambition to reduce animal toxicity studies.
Assuntos
Kluyveromyces/classificação , Kluyveromyces/enzimologia , Testes de Toxicidade/normas , Leveduras/classificação , Leveduras/enzimologia , Engenharia GenéticaRESUMO
Photodynamic therapy (PDT) is currently one of the most promising methods of cancer treatment. However, this method has some limitations, including a small depth of penetration into biological tissues, the low selectivity of accumulation, and hypoxia of the tumor tissues. These disadvantages can be overcome by combining PDT with other methods of treatment, such as radiation therapy, neutron capture therapy, chemotherapy, etc. In this work, potential drugs were obtained for the first time, the molecules of which contain both photodynamic and chemotherapeutic pharmacophores. A derivative of natural bacteriochlorophyll a with a tin IV complex, which has chemotherapeutic activity, acts as an agent for PDT. This work presents an original method for obtaining agents of combined action, the structure of which is confirmed by various physicochemical methods of analysis. The method of molecular modeling was used to investigate the binding of the proposed drugs to DNA. In vitro biological tests were carried out on several lines of tumor cells: Hela, A549, S37, MCF7, and PC-3. It was shown that the proposed conjugates of binary action for some cell lines had a dark cytotoxicity that was significantly higher (8-10 times) than the corresponding metal complexes of amino acids, which was explained by the targeted chemotherapeutic action of the tin (IV) complex due to chlorin. The greatest increase in efficiency relative to the initial dipropoxy-BPI was found for the conjugate with lysine as a chelator of the tin cation relative to cell lines, with the following results: S-37 increased 3-fold, MCF-7 3-fold, and Hela 2.4-fold. The intracellular distribution of the obtained agents was also studied by confocal microscopy and showed a diffuse granular distribution with predominant accumulation in the near nuclear region.
Assuntos
Complexos de Coordenação/farmacologia , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Estanho/farmacologia , Células A549 , Complexos de Coordenação/química , Células HeLa , Humanos , Células MCF-7 , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Porfirinas/química , Estanho/químicaRESUMO
BACKGROUND: The analysis of individual microRNAs (miRNAs) as a diagnostic and prognostic tool for the effective treatment of various diseases has aroused particular interest in the scientific community. The determination of circulating miRNAs makes it possible to assess biological changes associated with nutritional processes, the intake of dietary supplements and drugs, etc. The profile of circulating miRNAs reflects the individual adaptation of the organism to the effect of specific environmental conditions. OBJECTIVE: The objective of this study is to systematize the data and show the importance of circulating miRNAs as new potential biomarkers of the organism's response to the intake of various dietary supplements, drugs, and consider the possibility of their use in doping control. METHODS: A systematic analysis of scientific publications (ncbi.nlm.nih.gov) on the miRNA expression profile in response to the intake of dietary supplements and drugs most often used by athletes, and supposed their role as potential markers in modern doping control was carried out. RESULTS: The profile of circulating miRNAs is highly dependent on the intake of a particular drug, and, therefore, may be used as a marker of the effects of biologically active supplements and drugs including the substances from the Prohibited List of the World Anti-Doping Agency (WADA). CONCLUSION: Monitoring of circulating miRNAs can serve as a high-precision marker for detecting doping abuse in elite sports. However, it is necessary to conduct additional studies on the effect of complex drugs on the profile of circulating miRNAs and individual circulating miRNAs on a particular biological process.
Assuntos
MicroRNA Circulante , MicroRNAs , Biomarcadores , MicroRNA Circulante/genética , Suplementos Nutricionais , Humanos , MicroRNAs/genéticaRESUMO
EPO-Fc proteins have been under investigation as a potential drug for treating anaemia and have shown larger half-life values than other erythropoiesis-stimulating agents (ESAs). Sodium dodecyl sulfate/sodium N-lauroylsarcosinate polyacrylamide gel electrophoresis (SDS/SAR-PAGE) methods and subsequent immunoblotting are used for routine anti-doping analysis. This paper reports that EPO-Fc fusion proteins can be detected in serum samples by isoelectric focusing-polyacrylamide gel electrophoresis (IEF-PAGE) in carrier ampholyte-based gels with a pH 2-6 gradient after removing the Fc part via site-specific IdeS protease cleavage. The IdeS-digested EPO-Fc protein yields three fragments: two Fc fragments and one dimeric EPO-hinge fragment. After IEF-PAGE was followed by double Western blotting with chemiluminescent detection, the dimeric EPO-hinge fragment showed a unique isoelectric pattern, which differed from those of any other currently known analogue of EPO. We observed that the removal of the Fc fragment from EPO-Fc reduced the apparent molecular weight of entire fusion protein and increased its electrophoretic mobility. As a result, the band for the EPO-hinge fragment was located in a region between the rEPO and NESP standards, at which lower amounts of serum proteins are present. Simple and selective protocols for determining the EPO-Fc protein in human serum were developed to extend the methodological anti-doping arsenal. This protocol has been characterized. The limit of detection (LOD) of the IEF-PAGE method was 20 pg, and that of SDS/SAR-PAGE was 15 pg.