Effect of Stress on the Production of Antibodies and IL-2, IL-4, and IFNγ Depending on the Time of Antigen Administration and Evaluation of the Role of Opioid Receptors

The time of stress exposure relative to the moment of immunization affects the direction of the immunoregulatory effect of stress. In case of stress exposure preceding immunization, rotation stress stimulated the production of antibodies, while immobilization depressed it. After antigen injection, these types of stress had no significant effect on the formation of antibody-producing cells. Acute cold stress did not affect the number of antibody-forming cells before immunization, but stimulated the humoral response after it. At the same time, the effect of stress on the production of antibodies was leveled by blockade of opioid receptors with naloxone for rotation and immobilization, but was not canceled for acute cold stress. A similar pattern was revealed when analyzing the effect of stress exposure on cytokine production. Cold stress before antigen administration to mice had almost no effect on the production of IL-2, IL-4, IFNγ, while rotational and immobilization stress naloxone-dependently modulated the synthesis of IL-2 and IL-4. On the contrary, in animals subjected to stress after antigen administration, only cold stress significantly modulated the production of IL-2 and IL-4.

[Creation and Study of Triterpenoid Nanoparticles and Amphiphilic meso-Arylporphyrins]

This work is devoted to the study of nanoparticles based on amphiphilic meso-arylporphyrins and spherical amorphous nanoparticles (SANp), consisting of birch bark triterpenoids mixture. Nanoparticles were investigated by electron microscopy, dynamic light scattering, UV spectroscopy and fluorimetry. It was shown the efficiency of the inclusion of porphyrin sensitizer to the nanoparticles and the use of these nanoparticles as drug delivery system.

2H-NMR comparative study of phosphocholine group conformation in bilayers composed of diacyl and dialkyl phosphatidylcholines

Model membranes formed from 1,2-dihexadecyl-, 1,2-dipalmitoyl-, 1,2-ditetradecyl- or 1,2-dimyristoyl-rac-glycero-3-phosphocholine, deuterium-labelled at choline groups, in an excess of water were compared using 2H-NMR spectroscopy. The dynamics and conformation of the labelled choline segments were estimated based on spin-lattice relaxation time and residual quadrupole splittings. The trimethylammonium group of dialkyl phosphatidylcholine was shown to be more distant from the bilayer surface as compared with that of the diacyl analogues.

[Lipid inhibitors of phospholipase A2]

Results of studies of lipid inhibitors of phospholipase A2 are reviewed with a special emphasis on substrate specificity, special features of interfacial catalysis, and methods for the determination of the enzyme activity. The biological function of intracellular phospholipases is considered, and the possible use of inhibitors of a lipid nature for the modulation of the enzyme activity in pathological states of the human organism is discussed.