Endothelial dysfunction: comparative evaluation of ultrasound dopplerography, laser dopplerflowmetry and direct monitoring of arterial pressure for conducting pharmacological tests in rats

To study endothelial function when conducting vascular pharmacological tests in the norm and with the blockade of the nitric oxide synthesis by means of the ultrasound method for examining the central blood flow velocity in the femoral artery of the rat in comparison with changes of systemic haemodynamics and microcirculation velocity in the medial vastus muscle using laser Doppler flowmetr

Investigação do efeito reparador do gel de ectoína em modelo de queima térmica

Due to the ability to create complexes of water molecules on the surface of the mucous membrane, ectoine is a promising compound for the treatment of burns. In male rats (n=30), 2 thermal burns were counteracted under counter-anesthesia, one of which was treated by topical application of the test drugs for 7 days, and the other served as a control. On the 8th day, skin samples in the area of the burn were taken for morphological examination. Histological sections were then scored by independent experts. The best histological picture of thermally damaged tissues was demonstrated by animals receiving ectoine. A less significant, but pronounced reparative effect was observed in histological samples of the actovegin group. The least significant reparative effect was demonstrated by contractubex. Ectoine improved the histological picture, improved repair and reduced the inflammatory response of the tissues and can be recommended for further preclinical studies as a treatment for burns.Debido a la capacidad de crear complejos de moléculas de agua en la superficie de la membrana mucosa, la ectoina es un compuesto prometedor para el tratamiento de las quemaduras. En ratas macho (n = 30), 2 quemaduras térmicas se contrarrestaron con contraestesia, una de las cuales se trató mediante la aplicación tópica de los fármacos de prueba durante 7 días, y la otra sirvió como control. En el octavo día, se tomaron muestras de piel en el área de la quemadura para un examen morfológico. Las secciones histológicas fueron calificadas por expertos independientes. El mejor cuadro histológico de los tejidos dañados térmicamente fue demostrado por los animales que recibieron ectoína. Se observó un efecto reparador menos significativo, pero pronunciado en muestras histológicas del grupo actovegin. El efecto reparador menos significativo fue demostrado por contractubex. Ectoine mejoró el cuadro histológico, mejoró la reparación y redujo la respuesta inflamatoria de los tejidos y puede recomendarse para estudios preclínicos adicionales como tratamiento para las quemaduras.Devido à capacidade de criar complexos de moléculas de água na superfície da membrana mucosa, a ectoína é um composto promissor para o tratamento de queimaduras. Em ratos machos (n = 30), duas queimaduras térmicas foram combatidas sob anestesia, uma das quais foi tratada por aplicação tópica das drogas de teste por 7 dias, e a outra serviu como controle. No oitavo dia, amostras de pele na área da queimadura foram retiradas para exame morfológico. As secções histológicas foram então classificadas por especialistas independentes. O melhor quadro histológico dos tecidos termicamente lesados foi demonstrado pelos animais que receberam ectoína. Um efeito reparador menos significativo, mas pronunciado, foi observado em amostras histológicas do grupo da actovegina. O efeito reparador menos significativo foi demonstrado pelo contratoubex. Ectoine melhorou o quadro histológico, melhorou o reparo e reduziu a resposta inflamatória dos tecidos e pode ser recomendado para estudos pré-clínicos adicionais como tratamento para queimaduras

Association between <i>HSPA8</i> Gene Variants and Ischemic Stroke: A Pilot Study Providing Additional Evidence for the Role of Heat Shock Proteins in Disease Pathogenesis

HSPA8 is involved in many stroke-associated cellular processes, playing a pivotal role in the protein quality control system. Here we report the results of the pilot study aimed at determining whether HSPA8 SNPs are linked to the risk of ischemic stroke (IS). DNA samples from 2139 Russians (888 IS patients and 1251 healthy controls) were genotyped for tagSNPs (rs1461496, rs10892958, and rs1136141) in the HSPA8 gene using probe-based PCR. SNP rs10892958 of HSPA8 was associated with an increased risk (risk allele G) of IS in smokers (OR = 1.37; 95% CI = 1.07–1.77; p = 0.01) and patients with low fruit and vegetable consumption (OR = 1.36; 95% CI = 1.14–1.63; p = 0.002). SNP rs1136141 of HSPA8 was also associated with an increased risk of IS (risk allele A) exclusively in smokers (OR = 1.68; 95% CI = 1.23–2.28; p = 0.0007) and in patients with a low fruit and vegetable intake (OR = 1.29; 95% CI = 1.05–1.60; p = 0.04). Sex-stratified analysis revealed an association of rs10892958 HSPA8 with an increased risk of IS in males (risk allele G; OR = 1.30; 95% CI = 1.05–1.61; p = 0.01). Thus, SNPs rs10892958 and rs1136141 in the HSPA8 gene represent novel genetic markers of IS

Polymorphism of SERF2, the gene encoding a heat-resistant obscure (Hero) protein with chaperone activity, is a novel link in ischemic stroke

Background: Ischemic stroke (IS) is one of the most serious cardiovascular events associated with high risk of death or disability. The growing body of evidence highlights molecular chaperones as especially important players in the pathogenesis of the disease. Since six small proteins called “Hero” have been recently identified as a novel class of chaperones we aimed to evaluate whether SNP rs4644832 in SERF2 gene encoding the member of Hero-proteins, is associated with the risk of IS. Methods: A total of 1929 unrelated Russians (861 patients with IS and 1068 healthy individuals) from Central Russia were recruited into the study. Genotyping was done using a probe-based PCR approach. Statistical analysis was carried out in the whole group and stratified by age, gender and smoking status. Results: Analysis of the link between rs4644832 SERF2 and IS showed that G allele is the risk factor of IS only in females (OR=1.29, 95%CI 1.02–1.64, Padj=0.035). In addition, the analysis of associations of rs4644832 SERF2 and IS depending on the smoking status revealed that this genetic variant is associated with an increased risk of IS exclusively in non-smoking individuals (OR=1.26, 95%CI 1.01–1.56, P = 0.041). Discussion: Sex- and smoking interactions between rs4644832 polymorphism and IS may be related to the impact of tobacco components metabolism and sex hormones on SERF2 expression. Conclusion: The present study reveals the novel genetic association between rs4644832 polymorphism and the risk of IS suggesting that SERF2, the part of the protein quality control system, contributes to the pathogenesis of the disease

Eleven-amino acid peptides that mimic the erythropoietin α-helix B increases cell survival in endotheliocyte culture

Aim. To study the cytoprotective activity of peptides that mimic the spatial structure of the erythropoietin &alpha;-helix B in vitro. Material and methods. The experiment was performed on the primary cell culture of human endotheliocytes (HUVEC). Hydrogen peroxide (H2O2) was used to mimic oxidative stress. Cells were scattered in 96-well gelatin-coated plates with a density of 5 thousand cells per well. After 24 hours of incubation, the studied peptides were introduced - the basic peptide - Helix B surface peptide HBSP (QEQLERALNSS) and its derivatives EP-11-1 (UEHLERALNSS), EP-11-2 (UEQLERALNCS), EP-11-3 (UEQLERALNTS) in 3 concentrations - 5 &mu;g/ml, 30 &mu;g/ml and 50 &mu;g/ml. Cell viability was measured using the MTT test. Results. Initial screening of the cytoprotective activity of innovative peptides that mimic the erythropoietin &alpha;-helix B in vitro was performed. &nbsp;Our results demonstrate that the original HBSP peptide and its derivatives EP-11-1, EP-11-2, EP-11-3 have a pronounced (p&lt;0.05, compared with the control) cytoprotective effect. Derivatives EP-11-1, EP-11-2 does not differ from the base peptide HBSP in terms of the level of detected activity. When comparing the density of the formazan solution and the percentage of surviving endotheliocytes between the series of experiments with the base peptide HBSP and its derivatives, EP-11-3 showed significant superior cytoprotective effects when compared with HBSP (p&lt;0.05), all over the entire range studied concentrations. Conclusion. &nbsp;Derivatives of the original peptide with laboratory code EP-11-1, EP-11-2 do not differ in their cytoprotective action from the base peptide HBSP. While the derivatives with laboratory code EP-11-3 presented a higher and significant cytoprotective activity when compared to the base peptide HBS

Gamma-Synuclein Dysfunction Causes Autoantibody Formation in Glaucoma Patients and Dysregulation of Intraocular Pressure in Mice

Dysregulation of intraocular pressure (IOP) is one of the main risk factors for glaucoma. γ-synuclein is a member of the synuclein family of widely expressed synaptic proteins within the central nervous system that are implicated in certain types of neurodegeneration. γ-synuclein expression and localization changes in the retina and optic nerve of patients with glaucoma. However, the mechanisms by which γ-synuclein could contribute to glaucoma are poorly understood. We assessed the presence of autoantibodies to γ-synuclein in the blood serum of patients with primary open-angle glaucoma (POAG) by immunoblotting. A positive reaction was detected for five out of 25 patients (20%) with POAG. Autoantibodies to γ-synuclein were not detected in a group of patients without glaucoma. We studied the dynamics of IOP in response to IOP regulators in knockout mice (γ-KO) to understand a possible link between γ-synuclein dysfunction and glaucoma-related pathophysiological changes. The most prominent decrease of IOP in γ-KO mice was observed after the instillation of 1% phenylephrine and 10% dopamine. The total protein concentration in tear fluid of γ-KO mice was approximately two times higher than that of wild-type mice, and the activity of neurodegeneration-linked protein α2-macroglobulin was reduced. Therefore, γ-synuclein dysfunction contributes to pathological processes in glaucoma, including dysregulation of IOP

Structural changes of erythrocyte membrane revealed by 3D confocal optical profilometer

Abstract We examined hematological changes influenced by the experimental hypervitaminosis A. The 3D confocal optical profilometer was applied for assessment of the erythrocytes’ membrane structural changes influenced by an overdose of vitamin A. The blood smears were evaluated in terms of alterations of geometrical and optical parameters of erythrocytes for two groups of animals: oil base and retinol palmitate (n = 9 animals for each group). The results demonstrate that an overdose of retinol palmitate causes changes in the torus curvature and pallor of discocytes, their surface area and volume. The observed structural malformations of the shape of red blood cells become visible at the earlier preclinical stage of changes in animal state and behavior. With this in mind, the results of the study open a new area of research in the certain dysfunction diagnosis of red blood cells and have a great potential in the further development of new curative protocols

STUDY OF ANTIATHEROSCLEROTIC AND ENDOTHELIOPROTECTIVE ACTIVITY OF PEPTIDE AGONISTS OF EPOR/CD131 HETERORECEPTOR

Introduction. The drugs affecting a mitochondrial dysfunction, oxidative stresses, apoptosis and inflammation of the vascular wall, have a high potential for the prevention and treatment of atherosclerotic lesions. In this regard, the use of EPOR/CD131 heteroreceptor agonists which have a similar spectrum of pharmacological effects, is one of the promising strategies in the treatment of cardiovascular diseases.Materials and Methods. The study was carried out on 68 C57Bl/6J male mice. Atherosclerosis was simulated in transgenic animals with an endotheliospecific knockdown of the Polg gene by simulating a balloon injury and keeping on a Western diet. Then, the studied drugs were injected once every 3 days at the dose of 20 μg/kg for 27 days. On the 28-th day, the animals were euthanized and the area of atherosclerotic plaques was assessed. The gene expression associated with the processes of inflammation, antioxidant protection, apoptosis, and angiogenesis was also determined in the aortic tissues. In addition, the endothelium protective effect of peptides on primary cultures of endothelial cells of wild and transgenic Polg-D257A mice was studied.Results. No statistically significant effect of drugs on the area of lipid infiltration have been found. However, the studied peptides have significantly reduced the expression of proinflammatory genes (iNos, Icam1, Vcam1, Sele, Il6, Tnfa), the genes associated with angiogenesis (Vegfa, Kdr, and Hif1a), the expression of proapoptic factors; they decreased the Bax/Bcl-2 ratio by more than 1.5 times. In addition, when supplemented with H2 O2  in vitro, peptides dose-dependently increased endothelial cell survival.Conclusion. The erythropoietin-based peptides can be used to improve the functional state of the vascular wall against the background of atherosclerotic lesions and have a depressing effect on pathobiological processes associated with a mitochondrial dysfunction. In addition, the studied peptides have a significant endothelial protective effect in the induction of oxidative stress in vitro