Mimicking the cellular environment does not cause monocyte-derived macrophages to become phenotypically similar to Kupffer cells.

Resident macrophages of various mammalian organs are characterized by several distinctive features in their gene expression profile and phenotype, including involvement in the regulation of organ functions, as well as reduced sensitivity to proinflammatory activation factors. The reasons for the formation of such a specific phenotype remain the subject of intensive research. Some papers emphasize the role of the origin of organ macrophages. Other studies indicate that monocytes that develop in the red bone marrow are also able to form resident macrophages with a phenotype characteristic of a particular organ, but this requires appropriate microenvironmental conditions. In this article, we studied the possibility of differentiation of monocyte-derived macrophages into cells with a Kupffer-like phenotype under the influence of the main stromal components of Kupffer cells macrophage niche: Ito cells, liver sinusoid endotheliocytes and hepatocyte growth factor (HGF). It was found that Kupffer cells are characterized by several features, including increased expression of transcription factors Spic and Id3, as well as MUP family genes, Clusterin and Ngp genes. In addition, Kupffer cells were characterized by a higher proliferative activity. The expression of marker genes of Kupffer cells (i.e. Id3, Spic, Marco and Timd4) increased in monocyte-derived macrophages during coculture with Ito cells, liver sinusoid endothelial cells, macrophage colony-stimulating factor and HGF cells only by 3 days. However, the expression level of these genes was always higher in Kupffer cells. In addition, a complete coincidence of the expressed gene profile in monocyte-derived macrophages and Kupffer cells did not occur even after 3 days of culturing.

Novel Knowledge about Molecular Mechanisms of Heparin-Induced Thrombocytopenia Type II and Treatment Targets.

Heparin-induced thrombocytopenia type II (HIT II), as stated in the literature, occurs in about 3% of all patients and in 0.1-5% of surgical patients. Thrombosis develops in 20-64% of patients with HIT. The mortality rate in HIT II has not decreased using non-heparin treatment with anticoagulants such as argatroban and lepirudin. An improved understanding of the pathophysiology of HIT may help identify targeted therapies to prevent thrombosis without subjecting patients to the risk of intense anticoagulation. The review will summarize the current knowledge about the pathogenesis of HIT II, potential new therapeutic targets related to it, and new treatments being developed. HIT II pathogenesis involves multi-step immune-mediated pathways dependent on the ratio of PF4/heparin and platelet, monocyte, neutrophil, and endothelium activation. For years, only platelets were known to take part in HIT II development. A few years ago, specific receptors and signal-induced pathways in monocytes, neutrophils and endothelium were revealed. It had been shown that the cells that had become active realised different newly formed compounds (platelet-released TF, TNFα, NAP2, CXCL-7, ENA-78, platelet-derived microparticles; monocytes-TF-MPs; neutrophils-NETs), leading to additional cell activation and consequently thrombin generation, resulting in thrombosis. Knowledge about FcγIIa receptors on platelets, monocytes, neutrophils and FcγIIIa on endothelium, chemokine (CXCR-2), and PSGL-1 receptors on neutrophils could allow for the development of a new non-anticoagulant treatment for HIT II. IgG degradation, Syk kinase and NETosis inhibition are in the field of developing new treatment possibilities too. Accordingly, IdeS and DNases-related pathways should be investigated for better understanding of HIT pathogenesis and the possibilities of being the HIT II treatment targets.

[Endothelial damage and circadian blood pressure profile in rheumatoid arthritis].

AIM: To study the influence of the state of endothelium on the daily profile of arterial pressure (AP) in patients with rheumatoid arthritis (RA). MATERIALS AND METHODS: In 70 RA pts carried out C-reactive protein (CRP), vascular endothelial adhesion molecule type 1 (sVCAM-1), antigen von Willebrand Factor (AG WF), interleukin-8 (Il-8), rheumatoid factor (RF), IgG, endotheline-1 (ET-1), number of desquamated endotheliocytes cells (DE), VS, activity of renin by immunoenzyme analysis. The dysfunction of endothelium was evaluated by calculation of DE. The functional methods included the daily monitoring of arterial pressure (AP). RESULTS: Arterial hypertension (AH) occurred in 40 (57.1%) pts. RA pts are revealed the signs of endothelial dysfunction, about which significant differences among the indices of activation of endothelium in comparison with control group testify. ET-1, sVCAM-1, vWF AG, Il-8, CRP content was higher in RA pts. Reliably above there was a number of DE. Reliable differences according to these indices depending of RA activity were discovered. With conducting of correlation analysis it is revealed, that markers of the activation of endothelium: sVCAM-1, vWF AG positively correlated with increasing RF IgG and indices of the immune inflammation: CRP, and DE number. In patients suffering from RA, showed signs of endothelial dysfunction. The positive correlation between endothelial damage and daily profile of AP show the relationship of these processes. CONCLUSION: Positive correlations between the damage of endothelium and disturbance of AP daily profile testify about the interrelation of these processes.

Intracellular Reorganization of Cardiomyocytes in Dyslipidemic Cardiomyopathies.

The study examined the myocardial ultrastructural alterations in rats maintained on various atherogenic diets. It revealed the complex ultrastructural alterations of cardiomyocytes and endotheliocytes (including the lytic and destructive changes of the intracellular organelles, upregulation of the autophagocytosis in the cardiomyocytes, and necrobiosis with apoptosis of endotheliocytes) reflecting the cytopathic features of circulating cholesterol and lipoproteins, whose elevation determined the intensity of destructive processes. The revealed peculiarities in the changes of lipid inclusions (their osmiophilic transformation) in cardiomyocytes can be provoked by entry of cholesterol into the cells and its further metabolic modifications. During moderate dyslipidemia, the cardiomyocytes demonstrated the ultrastructural signs of induction of intracellular regeneration (marked with the clusters of polysomes in the intermyofibrillar and subsarcolemmal spaces with appearance of neogenic myofilaments) and upregulated pinocytotic activity. In all cases, up-regulated autophagocytosis in cardiomyocytes was accompanied by accumulation of myelin- and vacuole-like structures in the intercellular spaces and capillary lumens paralleled with appearance of activated forms of macrophages and fibroblasts in the myocardium.

Induced Pluripotent Stem Cell-Derived Hematopoietic Embryoid Bodies Secrete Sphingosine-1-Phosphate and Revert Endothelial Injury.

The possibility of sphingosine-1-phosphate production by induced pluripotent stem cells is examined to assess their potential in treatment of sepsis. The hematopoietic embryoid bodies were derived from the culture of 6-day-old differentiated induced pluripotent stem cells. These embryoid bodies secreted sphingosine-1-phosphate, an important bioactive lipid that regulates integrity of the pulmonary endothelial barrier, prevents elevation of its permeability, and impedes the formation of stress fibers in human endotheliocytes derived from umbilical vein. The data attest to potentiality of induced pluripotent stem cells in treatment of sepsis.

[Density of the endotheliocytic layer of the cornea of the eyeball as a function of age].

This article presents the results of measuring the number of corneal endotheliocytes in a unit area of descemet membrane surface in 546 volunteers of different ages. The average values of the density of the corneal posterior epithelium for the age intervals 40-49, 50-59, 60-69, 70-79, 80 years and older are shown, a constant decrease in the number of endotheliocyte cells as the number of years lived increases.

Inhibitory Effect of Interferons on Contractive Activity of Bovine Mesenteric Lymphatic Vessels and Nodes.

We studied the effect of IFNα-2b and IFNß-1a on phasic and tonic contractions of isolated bovine mesenteric lymphatic vessels and nodes. IFNα-2b and IFNß-1a in concentrations of 250-1000 U/ml produced dose-dependent negative chronotropic and inotropic effects on spontaneous phasic contractions and tonus of lymphatic vessels and nodes. In de-endothelialized lymphatic vessels and nodes, IFNα-2b and IFNß-1a in the same concentrations had less pronounced inhibitory effect on spontaneous contraction and tonus. L-NAME (100 µM) and charybdotoxin (0.1 µM with 0.5 µM apamine) significantly attenuated the inhibitory effect of IFNα-2b on phasic and tonic contractions of lymph nodes. L-NAME (100 µM) and indomethacin (10 µM) significantly reduced the IFNα-2b-induced inhibitory effect on phasic and tonic contractions of lymph node. These results indicate that IFNα-2b and IFNß-1a have a pronounced inhibitory effect on the phasic and tonic contractions of bovine mesenteric lymphatic vessels and nodes. The responses are endothelium-dependent and are determined by production of NO and endothelium-dependent hyperpolarizing factor by endotheliocytes in lymphatic vessels and by production of NO and prostacyclin by endotheliocytes in the lymphatic nodes.

Effect of Heparin on Contractile Activity of Lymph Node Capsule.

Experiments on smooth muscle strips isolated from the capsule of bovine mesenteric lymph node showed that heparin low concentrations (0.010-0.025 U/ml) stimulating spontaneous isometric phasic contractions of smooth muscles, but higher heparin concentrations reduced or even completely eliminated these contractions. The inhibitory effects of heparin were presumably realized via stimulation of NO production by endothelial cells of the subcapsular space followed by activation of ATP-sensitive potassium channels of capsular myocytes and via modulation of prostaglandin synthesis.

Pathological and vascular changes in the rat testiсle after experimental trauma.

Objective: Mechanical trauma to the testicles poses a potential risk of tissue destruction, disruption of local blood supply, and impairment of spermatogenesis, which can ultimately lead to infertility. Therefore, investigating this topic is crucial. The study aimed to identify cytological and morphological changes in the testicular tissue of laboratory rats following mechanical trauma to the organ. Methods: Observations were recorded on days 7, 14, 30, and 90 post-trauma. The experiment involved two groups of animals: a control group of healthy animals and an experimental group that sustained blunt mechanical trauma. Tissue samples were collected, fixed, dehydrated, and embedded in paraffin; subsequently, sections were prepared and stained. Structural changes in tissues and cells were documented using light and transmission electron microscopy. Results: In the experimental sample, notable changes included a decrease in organ weight, thickening of the protein shell and tubule walls, sclerotisation of the tubule membrane, narrowing of tubule diameter, reduced spermatozoa and spermatids titre, diminished capillary network and spermatogenic epithelium, uneven blood vessel lumen expansion, and decreased volume of Leydig cell nuclei. Additionally, in cells under different functional loads, the cytoplasm was vacuolated, mitochondrial cristae and the Golgi apparatus were diminished, cytoplasm volume decreased, karyopyknosis was observed, and uncharacteristic protrusions appeared on the surface of the cytoplasmic membrane. The severity of destruction at the cellular and tissue levels showed a positive correlation with time. Conclusion: The data obtained from these model sites can be predictive for clinical trials.

Effects of iron oxide nanoparticles on the gene expression profiles of cerebral endotheliocytes and astrocytes.

Iron oxide nanoparticles (IONPs) are considered as the most biocompatible magnetic materials suitable for biomedical applications. Nevertheless, there are many evidences of their toxicity for living organisms and partially neurotoxicity. The central nervous system is protected from undesirable substances circulating in the bloodstream by the blood-brain barrier (BBB). And even if being small enough, some nanoparticles could be able to penetrate cell membranes in other cells but will often be delayed by the BBB cells. However, the neurotoxicity of iron oxide is described even in the cases when IONPs should not uptake to the nervous system by experimental design. The aim of this study was to investigate what molecular changes in the cells-components of BBB - endotheliocytes and underlying astrocytes - may be caused by IONPs in the blood vessels of the brain. For this, a two-layer in vitro BBB model was created, consisting of rat cerebral endothelial cells and astrocytes. It was revealed that 100 and 200 mg/L of the nanoparticles induce metabolism alteration in the cells under study. Using RNA-sequencing, the up-regulation of pro-inflammatory chemokines encoding genes and changes in the expression of genes associated with detoxification in the endotheliocytes were demonstrated under the influence of 100 mg/L IONPs.

Red and near infrared light-stimulated angiogenesis mediated via Ca2+ influx, VEGF production and NO synthesis in endothelial cells in macrophage or malignant environments.

Irradiation with red or near-infrared (NIR) light in low level light therapy (LLLT) is found to stimulate cellular processes and bioenergetics, resulting in enhanced wound healing, pain control, neurodegenerative diseases treatment, etc. During light irradiation of tissues and organs, different cells are affected, though the connection between photostimulation of cells and their environmental conditions remains poorly understood. In this report, red/NIR light-stimulated angiogenesis is investigated using endothelial cells in vitro, with a focus on the capillary-like structure (CLS) formation and the respective biochemical processes in cells under conditions proximate to a healthy or malignant environment, which strongly defines angiogenesis. To model environmental conditions for endotheliocytes in vitro, the cell culture environment was supplemented by an augmented conditioned medium from macrophages or cancer cells. The biochemical processes in endothelial cell cultures were investigated with and without irradiation by red (650 nm) and near-infrared (808 nm) laser diodes and under normoxia or hypoxia conditions. A light-stimulated angiogenesis has been found, with a more efficient stimulation by 650 nm light compared to 808 nm light. It was shown that the irradiation with light promoted extracellular Ca2+ influx, fostered cell cycle progression, proliferation and NO generation in endothelial cells, and caused an increase in vascular endothelial growth factor (VEGF) production by endothelial cells and M2 macrophages under hypoxia conditions. The activation of VEGF production by macrophages was found to be associated with an increase in the number of M2 macrophages after light irradiation under hypoxia conditions. Thus, a new pathway of an activation of the endothelial cell metabolism, which is related with the extracellular Ca2+ influx after light irradiation, has been revealed. STATEMENT OF SIGNIFICANCE: Red/NIR light-stimulated angiogenesis has been studied using endothelial cells in vitro, with focus on CLS formation and the respective biochemical processes in cell models proximate to a healthy or malignant environment. A light-stimulated angiogenesis has been found, stimulated via extracellular Ca2+ influx, cell cycle progression, proliferation and NO generation, VEGF production increase by endothelial cells under hypoxia conditions.

S. aureus and E. coli change the force and work of adhesion between P- and E-selectins of endothelial cells and ligands of neutrophil granulocytes.

Thanks to the modification of the force spectroscopy method, when a neutrophil is fixed on the tip, and an endotheliocyte culture is grown on the substrate, the exact indicators of the adhesion force and adhesion work between cells have been investigated. The high variability of adhesion contacts in different donors associated with different expression profiles of neutrophils. It was found by flow cytometry that the EA.hy926 cell line actively expresses VCAM-1, as well as P- and E-selectin under the Staphylococcus aureus influence after 60 min of co-incubation. At the same time, the integral indicators of the adhesion force and adhesion work in the "neutrophil - endothelial cell" interaction were significantly inhibited by S. aureus in all studied donors. Since the VCAM-1 receptor is not involved in the adhesion bonds between neutrophils and endothelial cells, the suppression of the interaction is associated with the inhibition of P- and E-selectins, but direct receptors removal from the endothelial cells surface of the EA.hy926 cell line does not occur. Escherichia coli causes multidirectional effects in the system of interaction "neutrophil - endothelial cell", depending on the expression profile of the donor's neutrophils. However, the cumulative effect of interaction from all donors shows that in general, under the influence of E. coli, there is an increase in adhesion force and a suppression of adhesion work.

[Cerebral perfusion, arterial hypertension and endothelial dysfunction in rheumatoid arthritis]. / Mozgovaia perfuziia, arterial'naia gipertenziia i éndotelial'naia disfunktsiia pri revmatoidnom artrite.

To study the relationship between cerebral perfusion with arterial hypertension (AH) and the state of endothelium in patients with rheumatoid arthritis (RA). MATERIAL AND METHODS: Seventy-eight patients with RA were divided into two groups: with- and without AH.The functional methods included ultrasonic duplex angioscanning and dopplerografy of the extracranial and intracranial arteries of the head and neck and daily 24 hour monitoring of arterial blood pressure (BP). C-reactive protein (CRP), vascular endothelial adhesion molecule type 1 (sVCAM-1), von Willebrand Factor antigen (vWF AG), interleukin-8 (Il-8), rheumatoid factor (RF) IgG, endothelin-1 (ET-1) were determined by immunoenzyme analysis and velocity of sedimentation (VS). The dysfunction of endothelium was evaluated by calculation of the number of desquamated endotheliocytes cells (DE). RESULTS: AH occurred in 46 (59%) patients. Cerebral hypoperfusion was observed in patients with RA in whom the reduction in the high-speed indices of blood flow were correlated with BP increase. There were negative correlations between the linear speed of blood flow on the common carotid arteries and average day and night systolic BP, average day and night diastolic BP, indices of time systolic BP and diastolic BP and avariability of BP. The same results were established for the intracranial arteries: inverse correlations between the linear speed on the anterior cerebral arteries and average day systolic BP. The signs of endothelial dysfunction represented by significant differences among the indices of activation of endothelium in RA patients in comparison with the control group were shown. Content of ET-1, sVCAM-1, vWF AG, Il-8, CRP was higher in RA. The number of DE was significantly higher as well. These indices showed significant differences depending on RA activity. Correlation analysis revealed that the markers of endothelium activation sVCAM-1, vWF AG were positively correlated with the indices of immune inflammation. CONCLUSION: An increase in the activity of inflammatory process in RA leads to endothelial dysfunction, which contributes to the increase in the peripheral vascular resistance of cerebral arteries, reduction in the high-speed indices of blood flow, growth of BP variability and the increase in load by pressure.

A comparative study of protective action on endotheliocytes of fucoidan with different molecular weight and its mechanism / 中国药学杂志

OBJECTIVE: To study the protective action on endotheliocytes of fucoidan with different molecular weight from Laminaria japonica, and to explore its mechanism. METHODS: In vivo, endotheliocytes injury model in rats was used to examine the protective action on endotheliocytes of fucoidan with different molecular weight from Laminaria japonica; aortal endothelium section by HE stain under optical microscope was observed, and the the content of von willebrand factor (vWF) in plasma was determined by ELISA. In vitro, endothelial cell culture was used to determine the effect of fucoidan on content of vWF and endothelial microparticles (EMPs). RESULTS: In vivo, aortal endothelium section by HE stain under optical microscope showed low molecular weight (LMW) fucoidan had a remarkable protective effect, and the protection effect of LMWF fucoidans are stronger than middle molecular weight (MMW) fu-coidans. Administration of LMW fucoidan significantly decreased the vWF content. Administration of MMW fucoidan didn't change vWF content. In vitro, Administration of LMW fucoidan significantly decreased the vWF content and EMPs numbers. Administration of MMW fucoidan didn't change the vWF content and EMPs numbers. CONCLUSION: The LMW fucoidan fractions have good protective action on endothelial cells. The protective effect of LMW fucoidans is significantly stronger than MMW fucoidans. The protective action on endotheliocytes of LMW fucoidans relies on decreasing the concentration of EMPs and vWF, and thus inhibiting platelet activation indirectly.