ABSTRACT
A review of publications devoted to the analysis of genetic polymorphisms and features of the functioning of genes that affect the pharmacokinetics and pharmacodynamics of sodium-glucose cotransporter-2 inhibitors (SGLT2i) is presented. Objective of the study was to reveal information about genes whose polymorphism may affect the effectiveness of SGLT2i. The review was carried out in accordance with the PRISMA 2020 recommendations, the search for publications was carried out in the PubMed databases (including Medline), Web of Science, as well as Russian scientific electronic libraries eLIBRARY.RU from 1993 to 2022. Polymorphisms in the structure of several genes (SLC5A2, UGT1A9, ABCB1, PNPLA3) have been described that may affect the treatment of type 2 diabetes mellitus complicated by diseases such as chronic heart failure, chronic kidney disease, or non-alcoholic fatty liver disease. The information found on the genetic features of the development of the effects of SGLT2i is limited to a description of the differences in their pharmacokinetics. The relevance of currently available pharmacogenetic studies is largely constrained by small sample sizes.
Subject(s)
Diabetes Mellitus, Type 2 , Heart Failure , Sodium-Glucose Transporter 2 Inhibitors , Humans , Sodium-Glucose Transporter 2 Inhibitors/therapeutic use , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/complications , Risk Factors , Treatment Outcome , Heart Failure/etiologyABSTRACT
Juvenile idiopathic arthritis (JIA) is an autoimmune, inflammatory joint disease with complex genetic etiology. Previous GWAS have found many genetic loci associated with JIA. However, the biological mechanism behind JIA remains unknown mainly because most risk loci are located in non-coding genetic regions. Interestingly, increasing evidence has found that regulatory elements in the non-coding regions can regulate the expression of distant target genes through spatial (physical) interactions. Here, we used information on the 3D genome organization (Hi-C data) to identify target genes that physically interact with SNPs within JIA risk loci. Subsequent analysis of these SNP-gene pairs using data from tissue and immune cell type-specific expression quantitative trait loci (eQTL) databases allowed the identification of risk loci that regulate the expression of their target genes. In total, we identified 59 JIA-risk loci that regulate the expression of 210 target genes across diverse tissues and immune cell types. Functional annotation of spatial eQTLs within JIA risk loci identified significant overlap with gene regulatory elements (i.e., enhancers and transcription factor binding sites). We found target genes involved in immune-related pathways such as antigen processing and presentation (e.g., ERAP2, HLA class I and II), the release of pro-inflammatory cytokines (e.g., LTBR, TYK2), proliferation and differentiation of specific immune cell types (e.g., AURKA in Th17 cells), and genes involved in physiological mechanisms related to pathological joint inflammation (e.g., LRG1 in arteries). Notably, many of the tissues where JIA-risk loci act as spatial eQTLs are not classically considered central to JIA pathology. Overall, our findings highlight the potential tissue and immune cell type-specific regulatory changes contributing to JIA pathogenesis. Future integration of our data with clinical studies can contribute to the development of improved JIA therapy.
Subject(s)
Arthritis, Juvenile , Humans , Arthritis, Juvenile/genetics , Gene Expression Regulation , Quantitative Trait Loci , Cell Differentiation , Polymorphism, Single Nucleotide , Genome-Wide Association Study , Genetic Predisposition to Disease , Aminopeptidases/geneticsABSTRACT
A review of publications devoted to the analysis of genetic polymorphisms of the gene encoding the glucagon-like peptide type 1 receptor and some other genes directly and indirectly involved in the implementation of its physiological action is presented. The aim of the study: to search for information on genes polymorphism that can affect the effectiveness of glucagon-like peptide type 1 agonists. The review was carried out in accordance with the PRISMA 2020 recommendations, the search for publications was based on PubMed databases (including Medline), Web of Science, as well as Russian scientific electronic source eLIBRARY.RU from 1993 to 2022. The several genes polymorphisms (GLP1R, TCF7L2, CNR1, SORCS1, WFS1, PPARD, CTRB1/2) that may affect the course and therapy of type 2 diabetes mellitus, metabolic syndrome and obesity, was described. Single nucleotide substitutions in some regions of these genes can both decrease and increase the clinical efficacy of the treatment of diabetes mellitus and metabolic syndrome with the help of type 1 glucagon-like peptide agonists: exenatide, liraglutide. Data on the role of genetic variations in the structure of the products of these genes in the effectiveness of other type 1 glucacone-like peptide agonists have not been found.
Subject(s)
Diabetes Mellitus, Type 2 , Metabolic Syndrome , Humans , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/genetics , Glucagon/therapeutic use , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Glucagon-Like Peptide 1/therapeutic use , Venoms/therapeutic use , Peptides/genetics , Peptides/pharmacology , Peptides/therapeutic use , Glucagon-Like Peptide-1 Receptor/genetics , Glucagon-Like Peptide-1 Receptor/agonists , Glucagon-Like Peptide-1 Receptor/therapeutic useABSTRACT
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by significant and complex genetic etiology. GWAS studies have identified genetic variants associated with ASD, but the functional impacts of these variants remain unknown. Here, we integrated four distinct levels of biological information (GWAS, eQTL, spatial genome organization and protein-protein interactions) to identify potential regulatory impacts of ASD-associated SNPs (p < 5 × 10-8) on biological pathways within fetal and adult cortical tissues. We found 80 and 58 SNPs that mark regulatory regions (i.e. expression quantitative trait loci or eQTLs) in the fetal and adult cortex, respectively. These eQTLs were also linked to other psychiatric disorders (e.g. schizophrenia, ADHD, bipolar disorder). Functional annotation of ASD-associated eQTLs revealed that they are involved in diverse regulatory processes. In particular, we found significant enrichment of eQTLs within regions repressed by Polycomb proteins in the fetal cortex compared to the adult cortex. Furthermore, we constructed fetal and adult cortex-specific protein-protein interaction networks and identified that ASD-associated regulatory SNPs impact on immune pathways, fatty acid metabolism, ribosome biogenesis, aminoacyl-tRNA biosynthesis and spliceosome in the fetal cortex. By contrast, in the adult cortex they largely affect immune pathways. Overall, our findings highlight potential regulatory mechanisms and pathways important for the etiology of ASD in early brain development and adulthood. This approach, in combination with clinical studies on ASD, will contribute to individualized mechanistic understanding of ASD development.
Subject(s)
Autism Spectrum Disorder/genetics , Autism Spectrum Disorder/metabolism , Cerebral Cortex/metabolism , Adult , Brain/physiopathology , Databases, Genetic , Fetus , Gene Regulatory Networks/genetics , Genetic Predisposition to Disease , Genome-Wide Association Study , Humans , Neurodevelopmental Disorders/genetics , Polymorphism, Single Nucleotide/genetics , Protein Interaction Mapping/methods , Quantitative Trait Loci/geneticsABSTRACT
The use of osteoplastic materials allows extending indications for dental implants placement by considerable alveolar bone atrophy. The aim of the study was to reveal bone tissue metabolites which can be used as early bone destruction markers after bone augmentation procedure before any radiological signs occur. For this purpose the content of osteocalcinum, C-telopeptides, alkaline phosphatase and lactate dehydrogenase was examined in oral fluid. The increase of osteocalcinum and C-telopeptides and decrease activity of alkaline phosphatase and lactate dehydrogenase in comparison with control represented the pattern specific for bone destruction.
Subject(s)
Alveolar Ridge Augmentation , Bone Regeneration , Osteogenesis , Saliva/metabolism , Adult , Alkaline Phosphatase/analysis , Alkaline Phosphatase/metabolism , Collagen Type I/analysis , Collagen Type I/metabolism , Female , Humans , L-Lactate Dehydrogenase/analysis , L-Lactate Dehydrogenase/metabolism , Male , Middle Aged , Osteocalcin/analysis , Osteocalcin/metabolism , Peptides/analysis , Peptides/metabolism , Saliva/chemistryABSTRACT
The paper describes specific correlation of the clinical and molecular pathogenic features in various types of combined periapical lesions. Endodontic apical lesions combined with periodontal disease are characterized by specific radiological signs, shifts in oral fluid physical and chemical properties, the disruption of nitrogen metabolism, increased iron concentration, collagen disruption and impaired concentration ratio of calcium and phosphorous. General depression of immunoglobulin synthesis and increased concentration of cortisol and estradiol in oral fluid are also typical features of combined periapical lesions.
Subject(s)
Periapical Periodontitis/diagnosis , Calcium/analysis , Chronic Disease , Diagnosis, Differential , Estradiol/analysis , Female , Humans , Hydrocortisone/analysis , Immunoglobulins/analysis , Immunoglobulins/biosynthesis , Male , Periapical Periodontitis/diagnostic imaging , Periapical Periodontitis/metabolism , Periodontium/immunology , Periodontium/metabolism , Phosphorus/analysis , Radiography , Saliva/chemistry , Saliva/metabolismABSTRACT
The impact of natamycin on Aspergillus niger was analysed during the first 8 h of germination of conidia. Polarisation, germ tube formation, and mitosis were inhibited in the presence of 3 and 10 µM of the anti-fungal compound, while at 10 µM also isotropic growth was affected. Natamycin did not have an effect on the decrease of microviscosity during germination and the concomitant reduction in mannitol and trehalose levels. However, it did abolish the increase of intracellular levels of glycerol and glucose during the 8 h period of germination.Natamycin hardly affected the changes that occur in the RNA profile during the first 2 h of germination. During this time period, genes related to transcription, protein synthesis, energy and cell cycle and DNA processing were particularly up-regulated. Differential expression of 280 and 2586 genes was observed when 8 h old germlings were compared with conidia that had been exposed to 3 µM and 10 µM natamycin, respectively. For instance, genes involved in ergosterol biosynthesis were down-regulated. On the other hand, genes involved in endocytosis and the metabolism of compatible solutes, and genes encoding protective proteins were up-regulated in natamycin treated conidia.
ABSTRACT
We present molecular dynamics (MD) simulations to study the plausibility of the water replacement hypothesis (WRH) from the viewpoint of structural chemistry. A total of 256 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC) lipids were modeled for 400 ns at 11.7 or 5.4 waters/lipid. To obtain a single dehydrated bilayer relevant to the WRH, simulations were performed in the NP(xy)h(z)T ensemble with h(z) > 8 nm, allowing interactions between lipids in the membrane plane and preventing interactions between neighboring membranes via periodic boundary conditions. This setup resulted in a stable single bilayer in (or near) the gel state. Trehalose caused a concentration-dependent increase of the area per lipid (APL) accompanied by fluidizing the bilayer core. This mechanism has been suggested by the WRH. However, dehydrated bilayers in the presence of trehalose were not structurally identical to fully hydrated bilayers. The headgroup vector was in a more parallel orientation in dehydrated bilayers with respect to the bilayer plane and maintained this orientation in the presence of trehalose in spite of APL increase. The total dipole potential changed sign in dehydrated bilayers and remained slightly positive in the presence of trehalose. The model of a dehydrated bilayer presented here allows the study of the mechanisms of membrane protection against desiccation by different compounds.
Subject(s)
Lipid Bilayers/chemistry , Phosphatidylcholines/chemistry , Trehalose/chemistry , Water/chemistry , Molecular Dynamics SimulationABSTRACT
Airborne and waterborne fungal spores were compared with respect to cytoplasmic viscosity and the presence of ergosterol. These parameters differed markedly between the two spore types and correlated with spore survival. This suggests that the mode of spore dispersal has a bearing on cellular composition, which is relevant for the eradication of industrially relevant fungal propagules.
Subject(s)
Cytoplasm/chemistry , Ergosterol/analysis , Spores, Fungal/chemistry , Viscosity , Air , Electron Spin Resonance Spectroscopy , Microbial Viability , Microscopy , Microscopy, Electron, Scanning , Microscopy, Fluorescence , Spores, Fungal/ultrastructure , WaterABSTRACT
AIMS: To investigate the differences in membrane permeability and the effect on endocytosis of the polyene antimycotics nystatin, filipin and natamycin on germinating fungal conidia. METHODS AND RESULTS: The model system was Penicillium discolor, a food spoilage fungus. Filipin resulted in permeabilization of germinating conidia for the fluorescent probes TOTO-1 and FM4-64, but not for ferricyanide ions. Nystatin caused influx of all these compounds while natamycin did not. Untreated germinating conidia internalize the endocytic marker FM4-64. Pretreatment of germinating conidia with natamycin showed a dose and time dependent inhibition of endocytosis as judged by the lack of formation of early endosomal compartments. CONCLUSIONS: The results obtained from this study indicated that, unlike nystatin and filipin, natamycin is unable to permeabilize germinating conidia, but interferes with endocytosis in a dose and time dependent manner. SIGNIFICANCE AND IMPACT OF THE STUDY: Natamycin acts via a different mode of action than other polyene antimycotics. These results offer useful information for new strategies to prevent fungal spoilage on food products and infection on agricultural crops. For laboratory use, natamycin can be used as a specific inhibitor of early endocytosis in fungal cells.
Subject(s)
Antifungal Agents/pharmacology , Cell Membrane/metabolism , Endocytosis/drug effects , Penicillium/metabolism , Spores, Fungal/drug effects , Cell Membrane Permeability/drug effects , Filipin/pharmacology , Microbial Sensitivity Tests , Microscopy, Confocal , Microscopy, Fluorescence , Natamycin/pharmacology , Nystatin/pharmacology , Penicillium/growth & development , Spectroscopy, Electron Energy-Loss , Spores, Fungal/growth & developmentABSTRACT
There were disclosed syndrome of minimal thyroid insufficiency in each fourth patient with dental periimplantitis and absence of thyroid gland dysfunction in case of mucositis of periimplantitis origin. The data were presented of minimal thyroid insufficiency manifestations in cases of inflammatory complications of dental implantations the indicator of which was the content of overall and free thyroxin in oral fluid. There were determined common and differentiating peculiarities of oral fluid homeostasis in cases of dental periimplantitis and mucositis of periimplantitis origin.
Subject(s)
Dental Implants , Hypothyroidism/epidemiology , Hypothyroidism/physiopathology , Periodontal Diseases/epidemiology , Preoperative Care , Adult , Female , Humans , Male , Periodontal Diseases/diagnosis , Severity of Illness IndexABSTRACT
Ascospores of the fungus Talaromyces macrosporus are dormant and extremely stress resistant, whereas fungal conidia--the main airborne vehicles of distribution--are not. Here, physical parameters of the cytoplasm of these types of spores were compared. Cytoplasmic viscosity and level of anisotropy as judged by spin probe studies (electron spin resonance) were extremely high in dormant ascospores and during early germination and decreased only partly after trehalose degradation and glucose efflux. Upon prosilition (ejection of the spore), these parameters fell sharply to values characteristic of vegetative cells. These changes occurred without major volume changes that suggest dramatic changes in cytoplasmic organization. Azide reversibly inhibited prosilition as well as the decline in cytoplasmic parameters. No organelle structures were observed in etched, cryoplaned specimens of ascospores by low-temperature scanning electron microscopy (LTSEM), confirming the high cytoplasmic viscosity. However, cell structures became visible upon prosilition, indicating reduced viscosity. The viscosity of fresh conidia of different Penicillium species was lower, namely, 3.5 to 4.8 cP, than that of ascospores, near 15 cP. In addition the level of anisotropic motion was markedly lower in these cells (h(0)/h(+1) = 1.16 versus 1.4). This was confirmed by LTSEM images showing cell structures. The decline of cytoplasmic viscosity in conidia during germination was linked with a gradual increase in cell volume. These data show that mechanisms of cytoplasm conservation during germination differ markedly between ascospores and conidia.
Subject(s)
Cytoplasm/metabolism , Spores, Fungal/growth & development , Talaromyces/growth & development , Anisotropy , Electron Spin Resonance Spectroscopy , Spores, Fungal/ultrastructure , Stress, Mechanical , Talaromyces/ultrastructure , Temperature , ViscosityABSTRACT
Anhydrobiosis ("life without water") is the remarkable ability of certain organisms to survive almost total dehydration. It requires a coordinated series of events during dehydration that are associated with preventing oxidative damage and maintaining the native structure of macromolecules and membranes. The preferential hydration of macromolecules is essential when there is still bulk water present, but replacement by sugars becomes important upon further drying. Recent advances in our understanding of the mechanism of anhydrobiosis include the downregulation of metabolism, dehydration-induced partitioning of amphiphilic compounds into membranes and immobilization of the cytoplasm in a stable multicomponent glassy matrix.
Subject(s)
Plant Physiological Phenomena , Water , Adaptation, Physiological , Carbohydrate Metabolism , Cell Membrane/metabolism , Macromolecular Substances , Osmotic Pressure , Oxidative Stress , Plant Proteins/physiology , Proline/metabolism , Protein ConformationABSTRACT
The administration of eplir (a phospholipid-containing hepatoprotector), as well as of the enterosorbents polyphepan and EST-1 (an agent obtained from dry peat extract), to rats with tetrachloromethane-induced hepatitis protect the liver parenchyma against dystrophy, necrosis, and inflammation, reduce hyperfermentemia, decrease the blood bilirubin, ammonia, phenols, and malonaldehyde, and increase the urea content in blood serum, while not fully restoring all these biochemical parameters on the normal level. The treatment of rats with toxic hepatitis by a combination of eplir and enterosorbents is accompanied by a synergistic increase in the therapeutic efficacy of each component, leading to normalization of the biochemical parameters reflecting the functional slate of liver.
Subject(s)
Carotenoids/therapeutic use , Chemical and Drug Induced Liver Injury/prevention & control , Enterosorption , Phospholipids/therapeutic use , Animals , Carbon Tetrachloride Poisoning/pathology , Carbon Tetrachloride Poisoning/prevention & control , Chemical and Drug Induced Liver Injury/pathology , Drug Combinations , Drug Synergism , Lignin/therapeutic use , Liver/pathology , Male , RatsABSTRACT
The specific feature of this case presented is the prolonged clinical manifestations of cystitis despite long-term and diversified antibacterial therapy. Repeated ultrasonography was justifiable in this cases since it could reveal a cause of protracted cystitis. Thus, in the young child long-term dysuria and urinary infection may be caused by a bladder foreign body.
Subject(s)
Foreign Bodies/diagnostic imaging , Foreign Bodies/surgery , Urinary Bladder Diseases/diagnostic imaging , Urinary Bladder Diseases/surgery , Female , Humans , UltrasonographyABSTRACT
Storage of neem (Azadirachta indica) seeds is difficult because of their sensitivity to chilling stress at moisture contents (MC) > or =10% or imbibitional stress below 10% MC. The hypothesis was tested that an elevated gel-to-liquid crystalline phase transition temperature (Tm) of membranes is responsible for this storage behaviour. To this end a spin probe technique, Fourier transform infrared microspectroscopy, and electron microscopy were used. The in situ Tm of hydrated membranes was between 10 degrees C and 15 degrees C, coinciding with the critical minimum temperature for germination. During storage, viability of fresh embryos was lost within two weeks at 5 degrees C, but remained high at 25 degrees C. The loss of viability coincided with an increased leakage of K+ from the embryos upon imbibition and with an increased proportion of cells with injured plasma membranes. Freeze-fracture replicas of plasma membranes from chilled, hydrated axes showed lateral phase separation and signs of the inverted hexagonal phase. Dehydrated embryos were sensitive to soaking in water, particularly at low temperatures, but fresh embryos were not. After soaking dry embryos at 5 degrees C (4 h) plus 1 d of further incubation at 25 degrees C, the axis cells were structurally disorganized and did not become turgid. In contrast, cells had a healthy appearance and were turgid after soaking at 35 degrees C. Imbibitional stress was associated with the loss of plasma membrane integrity in a limited number of cells, which expanded during further incubation of the embryos at 25 degrees C. It is suggested that the injuries brought about by storage or imbibition at sub-optimal temperatures in tropical seeds whose membranes have a high intrinsic Tm (10-15 degrees C), are caused by gel phase formation.
Subject(s)
Rosales/physiology , Seeds , Cell Membrane/physiology , Cell Membrane/ultrastructure , Cold Temperature , Fertility , Germination , Preservation, Biological , Rosales/ultrastructure , Spectroscopy, Fourier Transform Infrared , Spin Labels , WaterABSTRACT
Acquisition of desiccation tolerance and the related changes at the cellular level in wheat (Triticum aestivum cv. Priokskaya) kernels during normal development and premature drying on the ear were studied using a spin probe technique and low temperature scanning electron microscopy. During normal development, the ability of embryos to germinate after rapid drying and rehydration was acquired after completion of morphological development, which is a few days before mass maturity. The acquisition of desiccation tolerance, as assessed by germination, was associated with an upsurge in cytoplasmic viscosity, the onset of accumulation of protein and oil bodies, and the retention of membrane integrity upon dehydration/rehydration. These features were also used to assess cellular desiccation tolerance in the cases when germination could not occur. Slow premature drying was used to decouple the acquisition of cellular desiccation tolerance from morphogenesis. Upon premature drying of kernels on the ears of plants cut at 5 d after anthesis, desiccation-tolerant dwarf embryos were formed that were able to germinate. When plants were cut at earlier stages poorly developed embryos were formed that were unable to germinate, but cellular desiccation tolerance was nevertheless acquired. In such prematurely dried kernels, peripheral meristematic endosperm cells had already passed through similar physiological and ultrastructural changes associated with the acquisition of cellular desiccation tolerance. It is concluded that despite the apparent strong integration in seed development, desiccation tolerance can be acquired by the meristematic cells in the developing embryo and cambial layer of endosperm, independently of morphological development.
Subject(s)
Adaptation, Physiological , Seeds/physiology , Triticum/physiology , Electron Spin Resonance Spectroscopy , Seeds/anatomy & histology , Seeds/growth & development , Triticum/embryology , Triticum/genetics , WaterABSTRACT
Plant somatic embryos usually lack desiccation tolerance. They may acquire such a tolerance upon preculture in the presence of abscisic acid (ABA), followed by slow drying, but not fast drying. ABA causes torpedo-shaped somatic embryos to lose their chlorophyll, suspend growth, exhibit low rates of respiration, and maintain elevated sucrose contents. The subsequent slow drying leads to a partial conversion of sucrose into oligosaccharides and the expression of dehydrin transcripts. Slow-dried, desiccation-tolerant somatic embryos have stable membranes, retain their native protein secondary structure, and have a densely packed cytoplasmic glassy matrix. Fast-dried, desiccation-sensitive somatic embryos experience some loss of phospholipids and an increase in free fatty acids. Their proteins show signs of denaturation and aggregation, and the glassy matrix has reduced hydrogen bonding. The reduced conversion of sucrose into oligosaccharides appears not to underlie dehydration injury. Proteins in slow-dried somatic embryos, not pretreated with ABA, also show signs of denaturation, which might be attributed to low sugar contents. We conclude that by reducing cellular metabolism, ABA maintains high sugar contents. These sugars contribute to the stability of membranes, proteins, and the cytoplasmic glassy matrix, whereas slow drying permits a further fine tuning of this stability. Partitioning of endogenous amphiphiles from the cytoplasm into membranes during drying may cause membrane perturbance, although it might confer protection to membranes in the case of amphiphilic antioxidants. The perturbance appears to be effectively controlled in desiccation-tolerant systems but not in sensitive systems, for which we suggest dehydrins are responsible. In this context, the low desiccation tolerance in the presence of ample sugars is discussed.
Subject(s)
Carbohydrate Metabolism , Desiccation , Seeds/metabolism , Abscisic Acid/pharmacology , Disaccharides/metabolism , Oligosaccharides/metabolism , Seeds/drug effects , Seeds/growth & development , Spectroscopy, Fourier Transform InfraredABSTRACT
The interaction of lipid soluble spin labels with wheat embryo axes has been investigated to obtain insight into the structural organization of lipid domains in embryo cell membranes, using conventional electron paramagnetic resonance (EPR) and saturation transfer EPR (ST-EPR) spectroscopy. Stearic acid spin labels (n-SASL) and their methylated derivatives (n-MeSASL), labelled at different positions of their doxyl group (n=5, 12 and 16), were used to probe the ordering and molecular mobility in different regions of the lipid moiety of axis cell membranes. The ordering and local polarity in relation to the position of the doxyl group along the hydrocarbon chain of SASL, determined over the temperature range from -50 to +20 degrees C, are typical for biological and model lipid membranes, but essentially differ from those in seed oil droplets. Positional profiles for ST-EPR spectra show that the flexibility profile along the lipid hydrocarbon chain does exist even at low temperatures, when most of the membrane lipids are in solid state (gel phase). The ordering of the SASL nitroxide radical in the membrane surface region is essentially higher than that in the depth of the membrane. The doxyl groups of MeSASLs are less ordered (even at low temperatures) than those of the corresponding SASLs, indicating that the MeSASLs are located in the bulk of membrane lipids rather than in the protein boundary lipids. The analysis of the profiles of EPR and ST-EPR spectral parameters allows us to conclude that the vast majority of SASL and MeSASL molecules accumulated in embryo axes is located in the cell membranes rather than in the interior of the oil bodies. The preferential partitioning of the doxyl stearates into membranes demonstrates the potential of the EPR spin-labelling technique for the in situ study of membrane behavior in seeds of different hydration levels.
Subject(s)
Membrane Lipids/chemistry , Triticum/chemistry , Biophysical Phenomena , Biophysics , Cell Membrane/chemistry , Cyclic N-Oxides , Electron Spin Resonance Spectroscopy/methods , Spin Labels , Stearates/chemistry , Triticum/embryologyABSTRACT
In chronic CCl4-hepatitis in rats phospholipid-containing hepatoprotectors, essentiale and eplir differ in their influence on the therapeutic effect of prednisolone; essentiale does not change the antiproliferative effect of the glucocorticoid and weakens its membrane-stabilizing effect, eplir increases these therapeutic effects of prednisolone. Besides, eplir, in distinction from essentiale, reduces lipid accumulation in the liver and hypoproteinemia which are induced by prednisolone.