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Lipid balance was studied in female patients with late rheumatoid arthritis, their healthy female relatives liable to autoimmune diseases, and healthy women without family history of autoimmune diseases. Previous studies showed that the relatives of patients with rheumatoid arthritis suffered from frequent stubborn common infections, which prompted us to analyze the relationship between lipid metabolism and the infectious syndrome parameters. Blood serum and cells were collected for analysis when females had no clinical symptoms of infections (in all groups) or laboratory signs of inflammatory process (in the relatives and controls). Proatherogenic shifts in serum lipid composition presumably associated with frequent lasting infections were detected in individuals liable to rheumatoid arthritis development. Elevated cholesterol content in mononuclear leukocytes in this group could lead, in turn, to dysfunctions of these cells and augment the defects of anti-infection defense. The parameters of lipid balance in patients with late rheumatoid arthritis were close to the age-specific norm.

Unlabelled: The aim of this work was to study the peripheral blood monocyte functions in patients with advanced RA and their predisposed to RA relatives in comparison with those in women, not hereditary tainted with autoimmune diseases (donors). In groups comprising 24 RA patients, 24 relatives, and 24 donors the following monocyte functions were assessed: engulfment and digestion (radioisotope method); release of lysosomal glucuronidase in response to opsonized zymosan (fluorescent method); reactive oxygen species (ROS) generation (chemiluminescence), and serum levels of proinflammatory cytokines (ELISA). The monocyte specific feature in patients and their relatives is chiefly extracellular digestion due to the delayed engulfment. The digestive activity, probably inhibited in relatives, is increased in advanced RA. ROS generation by the cells and serum levels of TNF-alpha and IL-1-beta are abundant both in the patients and their relatives. High levels of pro-inflammatory cytokines, presumably, of monocyte origin, and increased levels of stimulated ROS generation may be due to the priming and prolonged activation of monocytes in relatives., Conclusion: We show for the first time that the functioning of circulating mononuclear phagocytes in the assumed to be healthy predisposed to RA individuals differs from that in the healthy people not hereditary tainted with autoimmune diseases and in general resembles the functioning of the cells in the patients with advanced RA.

In this paper, we continue our studies of the previously discovered [O.A. Zabotina, D.A. Ayupova, O.N. Larskaya, O.N. Nikolaeva, G.I. Petrovicheva, A.I. Zabotin, Physiologically active oligosaccharides, accumulating in the roots of winter wheat during adaptation to low temperature, Russian Journal of Plant Physiology 45 (1998) 262] oligosaccharin (physiologically active oligosaccharide) GXAG, which stimulates the acquisition of freezing tolerance in winter varieties of Triticum aestivum L. The transient accumulation of GXAG in the tissues of winter wheat correlates with the temporal activation of cell wall glycosidases during the first hours of cold acclimation (2 degrees C). This finding suggests that the oligosaccharin is liberated as a result of the intensification of hemicellulose turnover. At low concentrations, GXAG initiates the acquisition of freezing tolerance in winter plants, in a manner similar to ABA, even at room temperature. The resultant effect of ABA and GXAG on the freezing tolerance of winter wheat depends on the sequence of pre-treatments with these two factors. When seedlings are pre-treated with GXAG a few hours before treatment with ABA, the effect is synergistic, and its impact depends on the duration of pre-treatment with GXAG. When ABA is applied first, the resultant effect on freezing tolerance is additive. The results obtained here lead to the conclusion that oligosaccharin, accumulating during the first hours of cold acclimation, functions as a partner of ABA during the initiation of freezing tolerance acquisition in winter plants. We hypothesize that GXAG increases cell receptivity to ABA signaling.

A study was made of the contents of the main polysaccharide fractions in the cell wall, and extracellular polysaccharides, and of the activity of cell wall enzymes during cultivation of suspension culture of cells of the winter wheat Triticum timopheevii Zhuk. It was shown that within 3 days of cultivation (a phase enriched in dividing cells), on the background of increased callose contents in plant cells, amounts of pectins and hemicelluloses extracted by 4N alkali decreased. The content of polysaccharides reached its initial level by the end of culturing. A parallel analysis of glycosidase activity in cell walls has shown their considerable activation at the stage enriched by dividing cells, which decreased at a transition of culture into the stationary level. The increased activity of hydrolyzing enzymes was combined with an increased efflux of extracellular polysaccharides into culture medium. The detected changes in polysaccharide composition of the cell wall at the first phase indicate its qualitative changes during cell wall reconstruction at the beginning of cytokines, whereas extensive expansion of cell wall was seen on the phase of elongation.

Radioisotope study of mononuclear phagocytes from patients with rheumatoid arthritis showed impaired ingestion of bacteria in the presence of pronounced digestive activity. Excessive accumulation methylumbelliferyl phosphate beta-glucuronide (product of hydrolysis catalyzed by glucuronidase released from cells) into the incubation medium was observed. This was probably related to the predominance of extracellular digestion.

We studied the dynamics of endogenous content of bioactive oligosaccharides in the roots of winter wheat seedlings. Previously these oligosaccharides proved to mediate development of frost resistance during the first days of hardening (Zabotina et al., 1998). The changes in their endogenous content can be described by a single-humped curve peaking 6 h after the onset of frost hardening. The capacity of these polysaccharides to increase frost resistance (LT50 was evaluated by leakage of electrolytes) when added to growth medium did not depend on the pretreatment duration (from 1.5 to 18 h) but decreased if they were introduced in the course of the adaptive response. Inhibition of the adaptive response by inhibitors of RNA and protein synthesis was ceased in the presence of the oligosaccharides. We believe that the oligosaccharides that are products of metabolism of the cell wall polysaccharides are involved in adaptation to low temperature.

Two physiologically active oligosaccharide fractions were isolated from pectin of Pisum sativum L. cell wall after its partial acid hydrolysis. These fractions displayed stimulating and inhibiting effects on root formation in thin-layer explants. The subsequent separation of these fractions by gel permeation and anion-exchange chromatography resulted in fractions with effective concentrations two orders of magnitude lower than the concentrations of the initial fractions. The resulting oligosaccharides displayed their effect on the earliest stage of the rhizogenesis associated with formation of root primordias. The rhizogenesis-inhibiting fraction suppressed cell division by 30-50%. The stimulating fraction mainly contained fragments of xyloglucan and galactan, and the inhibiting fraction contained fragments of xyloglucan, galactan, and arabinan. The polymerization degrees of the stimulating and of the inhibiting oligosaccharides were 10-11 and 5-6, respectively.

Role of monovalent cations in chloroplast membranes was investigated using chlorophyll a as an endogenous fluorescent probe. It is found using specific membrane modification by trypsin and lipophylic polypeptide, gramicidin S, that cations cause changes in the chlorophyll microenvironment. The mechanism of these changes is suggested to be an induction of the protein conformational ability, which results in the rearrangement of their lipid environment and in the differentiation of the latter.