Biomeditsinskaya khimiya最新文献

A comparative analysis of HaCaT keratinocyte proteins has been performed after cell exposure to subtoxic doses (5 J/cm² and 25 J/cm²) of ultraviolet A (UVA) radiation. 930 proteins were identified by two or more unique peptides. More than half of all identified proteins (54.5%) demonstrated at least 2-fold increase in their relative content after HaCaT keratinocyte irradiation with a cumulative dose of 5 J/cm², while a decrease in the relative content was found only for 4 proteins. Irradiation of keratinocytes with a cumulative dose of 25 J/cm² resulted in a decrease in the proportion of up-regulated proteins (43.0%) and an increase in the number of down-regulated proteins (84). Among the proteins with increased relative content in HaCaT keratinocytes the most proteins were associated with "cell motility" (GO: 0048870), as well as regulation of cell shape and size, cell morphogenesis, and skin remodeling.

Ischemia-reperfusion injury (IRI) is a complex process accompanying cessation of blood supply to an organ or tissue followed by subsequent restoration of blood circulation. The IRI is especially prominent in surgery and organ transplantation. One of the strategies for reducing organ and tissue damage during transplantation is regulation of intracellular ion concentrations. Maintenance of ion concentrations in the cell during damage development can be controlled by influencing voltage-dependent ion channels with certain types of compounds. We propose the peptide toxins tropic to calcium (omega-hexatoxin-Hv1a) and sodium (mu-agatoxin-Aa1a) voltage-dependent ion channels as potential agents reducing IRI. The toxins were obtained using solid-phase peptide synthesis. The IRI modeling for evaluation of the action of toxins was carried out on a culture of epithelial cells CHO-K1 during their incubation under conditions of hypoxia and nutrient deprivation followed by subsequent replenishment of the nutrient medium. The level of cell death, concentrations of calcium, sodium, potassium ions, and pH were recorded using a multimodal plate reader and fluorescent dyes. Experiments have shown that regardless of different mechanisms of action, both toxins reduced the development of CHO-K1 cell death by changing ion concentrations and maintaining the pH level.

Renalase (RNLS) is a protein involved in the regulation of blood pressure; it has various functions inside and outside cells. The twenty-membered peptide RP220, corresponding to the amino acid sequence of human RNLS 220-239, reproduces a number of effects of extracellular RNLS and can bind to many intracellular proteins in the kidney. The RP220 sequence contains several cleavage sites for extracellular proteases, which could potentially produce RP224-232 and RP233-239 peptides. The aim of this work was to perform proteomic profiling of kidney tissue from normotensive Wistar Kyoto (WKY) rats and spontaneously hypertensive rats (SHR) derived from WKY, using potential proteolytic fragments (RP224-232 and RP233-239) of the RP220 peptide as affinity ligands, and to compare these proteomic profiles with the profiles obtained using the parent RP220 peptide. The obtained results indicate that the relative content of proteins bound to the RNLS peptides in SHR, compared to that in WKY rats, changes most significantly in the case of the RP224-232 peptide. Almost all of these proteins, with a few exceptions, are associated with cardiovascular pathology, many with hypertension. The results of our work indicate that proteolytic processing of RP220 does not lead to the inactivation of this peptide, but to a change in its ligand/regulatory properties, as well as the repertoire of potential protein partners and, consequently, protein-protein interactions that may have possible pharmacological application.

In clinical studies, the purinergic receptor P2X3 is considered as a molecular target for pain correction in spinal sensory neurons by highly selective antagonists based on diaminopyrimidine derivatives. In the CNS, P2X3 receptors are involved in synaptic plasticity underlying memory and learning. Currently, potent and selective allosteric modulators of P2X3 and P2X2/3 receptors have been recognized among diaminopyrimidine derivatives. These include 5-(5-iodo-2-isopropyl-4-methoxyphenoxy)pyrimidine-2,4-diamine (Ro-4 or AF-353), gefapixant, which have a good pharmacokinetic profile and are less active with respect to a wide range of kinases, receptors, and ion channels. Although the therapeutic value of P2X3 receptor blockade in CNS neurons has not been studied, however, certain evidence exists in the literature that this receptor could represent a new target in the search for antiepileptic drugs, as well as drugs that reduce anxiety and stress. The aim of the work was to study the effect of the P2X3 receptor antagonist AF-353 (Ro-4) on the neuronal bioenergetic health index (BHI) in a primary mixed hippocampal culture. The P2X3 receptor blockade in embryonic and postnatal mouse hippocampal neuron cultures increased non-mitochondrial respiration by 27.5% and 15.8%, respectively, proton loss by 31.0% and 61.4%, and decreased basal respiration by 89% and 39% compared to the control. The neuronal BHI decrease in the postnatal culture was 68% compared to the control. The obtained results indicate the effect of AF-353 on mitochondrial respiration of a primary mixed culture of hippocampal neurons; this reveals the potential of the P2X3 receptor as a pharmacological target in hypoxic conditions of the brain.

Renalase (RNLS) is a protein playing different roles inside and outside cells. A 20-mer synthetic peptide corresponding to the human RNLS amino acid sequence 220-239 (RP220) exhibits a number of pharmacologically attractive activities in vitro and in vivo and can bind to many renal intracellular proteins. The RP220 sequence contains several cleavage sites for extracellular and circulating proteases. Here, we investigated the interaction of model proteins with the renalase peptide RP220 and a synthetic peptide corresponding to the amino acid sequence of RNLS 224-232, named RP224-232. We also performed affinity-based proteomic profiling of normotensive rat kidney samples with these peptides as affinity ligands. The obtained results indicate that both peptides exhibit almost the same affinity for model proteins (pyruvate kinase and lactate dehydrogenase), and the kidney proteomic profiles differ slightly. At the same time, the relative content of a number of kidney proteins bound to the RP224-232 peptide was even higher than in the case of using RP220. This suggests that proteolytic processing of RP220 does not inactivate this peptide; moreover, it could contribute to the formation of shorter peptides with additional pharmacological activities.

Serious side effects of the chemotherapeutic drug doxorubicin prompt researchers to develop systems for its targeted delivery to cells. In this work, we continued the study on the effect of using two vectors in a phospholipid delivery system of doxorubicin (Dox) for targeted therapy of breast cancer. We have obtained a composition NPh-Dox-cRGD-Fol(2.0) with the same linker length for both targeting ligands, cRGD and folic acid (PEG 2000). The resulting composition NPh-Dox-cRGD-Fol(2.0) with a particle size less than 50 nm and with 99% Dox incorporated into nanoparticles in an experiment on drug release at different pH values (5.0 and 7.4) showed a faster release and a high level of Dox compared to the phospholipid nanoform and a composition containing only the cRGD peptide. In vitro experiments on MDA-MB-231 breast cancer cells expressing the folate receptor and integrin αvβ3 demonstrated an increase in the total accumulation and internalization of Dox upon incubation with the dual-vector composition compared to the control samples. On the MCF-7 breast cancer cell line (expressing only the folate receptor), a similar effect was observed upon incubation with the single-vector composition containing folic acid (NPh-Dox-Fol(2.0)). In experiments with normal Wi-38 cell line, the internalization and total accumulation of the drug were comparable for both the free substance and the vector compositions. After 24 h-incubation of MDA-MB-231 cells with Dox-containing (10 μg/ml DOX) samples, the lowest percentage of living cells was observed for the studied dual-vector composition NPh-Dox-cRGD-Fol(2.0). On MCF-7 cells, the cytotoxic effect was manifested equally for the studied samples. The study of the cell death pathway on MDA-MB-231 cells showed the predominance of the apoptotic pathway (late apoptosis), while in the case of MCF-7 the necrosis pathway predominated. The cell cycle study performed using MDA-MB-231 cells (folate receptor (+) and integrin αvβ3 (+)) revealed an increase in the percentage of cells in the G0/G1 phase was noted thus indicating apoptotic cell death during incubation with NPh-Dox-cRGD-Fol(2.0). No differences were found between the samples in experiments performed on MCF-7 cells (folate receptor (+) and integrin αvβ3 (-)).

The effect of the nitric oxide donor S-nitrosoglutathione on the level and activity of organic anion transporting polypeptide 1B1 (OATP1B1), as well as the expression of the SLCO1B1 gene encoding the transporter protein, was investigated in HepG2 cells. The study has shown that treatment of cells with S-nitrosoglutathione for 3 h did not influence the content and activity of OATP1B1. Incubation with S-nitrosoglutathione (10-500 μM) for 24 h increased SLCO1B1 expression, the content of OATP1B1, and activity of the transporter protein. Induction of the OATP1B1 protein by the NO donor was suppressed by the soluble guanylate cyclase (sGC) inhibitor, 10 μM ODQ (1H-[1,2,4]oxadiazolo-[4,3-a]quinoxaline-1-OH). Thus, the study has shown that S-nitrosoglutathione, acting through the NO-sGC-cGMP signaling pathway, increased SLCO1B1 gene expression, accompanied by the increase in the transporter protein content and its activity in cells.

Systemic lipopolysaccharide (LPS)-induced inflammation has a significant impact on various organs, including the male reproductive system. In this study, we have demonstrated that LPS-induced inflammation causes oxidative stress in mouse testes, reduces expression of genes encoding the catalytic subunit of glutamate-cysteine ligase (Gclc) and superoxide dismutase 2 (Sod2). Inflammation suppressed transcription of genes involved in differentiation and metabolic regulation of testicular cells and sperm maturation: in the LPS group, the expression of the Amh, Lepr, Eif2b4 genes was approximately 3 times lower compared to the control group. The intake of probiotic microorganisms caused a decrease in the intensity of lipid peroxidation, which was manifested in a decrease in the level of conjugated dienes (CD) compared to the LPS group, contributed to maintaining the level of expression of genes supporting the antioxidant status, as well as genes supporting the functionality of the mouse testes. The data obtained suggest that probiotics may be considered as potential tools for maintaining male reproductive function under conditions of inflammatory processes.

The interaction of inactivated poliovirus vaccine strains with oriented antibodies immobilized to protein A via Fc fragments has been investigated. Using an SPR biosensor, the kinetic and equilibrium parameters of the interaction of vaccine attenuated polioviruses of the Sabin strains type 1 and type 2, inactivated by various methods were determined. The strongest interaction was observed between polyclonal antibodies to Sabin strain type 2 poliovirus and Sabin strain type 2 poliovirus inactivated with β-propiolactone, KD = 1.04⋅10-11 M, as well as the interaction of monoclonal antibodies to Sabin strain type 1 poliovirus and Sabin strain type 1 poliovirus inactivated with formaldehyde, KD = 1.39⋅10-11 M. The high-affinity interaction of inactivated vaccine polioviruses of the Sabin strains type 1 and type 2 with immobilized antibodies indicates that the D-antigen retained its structure after virus inactivation with β-propiolactone or formaldehyde.

Exogenous N-terminal fragments of galanin, which are agonists of the GalR2 receptor, have therapeutic potential in experimental cardiac pathology. This implies the need to study their proteolytic stability in biological environments. The aim of this work was to evaluate the proteolytic degradation of galanin G1 (GWTLNSAGYLLGPHAIDNHRSFSDKHGLT-NH2), its natural and modified fragments G2 and G3 (WTLNSAGYLLGPHA-OH and WTLNSAGYLLGPβAH-OH, respectively) in human plasma. The peptides were obtained by solid-phase synthesis using the Fmoc methodology, purified by HPLC; their structure was confirmed by MALDI-TOF mass spectrometry and 1H-NMR spectroscopy. The kinetics of galanins G1-G3 degradation in blood plasma was studied by 1H-NMR spectroscopy based on changes in the intensity of Trp2 signals at 310 K. The results indicate a higher proteolytic stability of the G3 peptide compared to the natural G2 fragment and full-length galanin G1. They indicate the potential of using modified peptide agonists of GalR2 receptors to protect vital organs in pathophysiological conditions.