MicroRNAs participate in the regulation of apoptosis and oxidative stress-related gene expression in rabbits infected with Lagovirus europaeus GI.1 and GI.2 genotypes.

MicroRNAs (miRs) are a group of small, 17-25 nucleotide, non-coding RNA that regulate gene expression at the post-transcriptional level. To date, little is known about the molecular signatures of regulatory interactions between miRs and apoptosis and oxidative stress in viral diseases. Lagovirus europaeus is a virus that causes severe disease in rabbits (Oryctolagus cuniculus) called Rabbit Hemorrhagic Disease (RHD) and belongs to the Caliciviridae family, Lagovirus genus. Within Lagovirus europaeus associated with RHD, two genotypes (GI.1 and GI.2) have been distinguished, and the GI.1 genotype includes four variants (GI.1a, GI.1b, GI.1c, and GI.1d). The study aimed to assess the expression of miRs and their target genes involved in apoptosis and oxidative stress, as well as their potential impact on the pathways during Lagovirus europaeus-two genotypes (GI.1 and GI.2) infection of different virulences in four tissues (liver, lung, kidneys, and spleen). The expression of miRs and target genes related to apoptosis and oxidative stress was determined using quantitative real-time PCR (qPCR). In this study, we evaluated the expression of miR-21 (PTEN, PDCD4), miR-16b (Bcl-2, CXCL10), miR-34a (p53, SIRT1), and miRs-related to oxidative stress-miR-122 (Bach1) and miR-132 (Nfr-2). We also examined the biomarkers of both processes (Bax, Bax/Bcl-2 ratio, Caspase-3, PARP) and HO-I as biomarkers of oxidative stress. Our report is the first to present the regulatory effects of miRs on apoptosis and oxidative stress genes in rabbit infection with Lagovirus europaeus-two genotypes (GI.1 and GI.2) in four tissues (liver, lungs, kidneys, and spleen). The regulatory effect of miRs indicates that, on the one hand, miRs can intensify apoptosis (miR-16b, miR-34a) in the examined organs in response to a viral stimulus and, on the other hand, inhibit (miR-21), which in both cases may be a determinant of the pathogenesis of RHD and tissue damage. Biomarkers of the Bax and Bax/Bcl-2 ratio promote more intense apoptosis after infection with the Lagovirus europaeus GI.2 genotype. Our findings demonstrate that miR-122 and miR-132 regulate oxidative stress in the pathogenesis of RHD, which is associated with tissue damage. The HO-1 biomarker in the course of rabbit hemorrhagic disease indicates oxidative tissue damage. Our findings show that miR-21, miR-16b, and miR-34a regulate three apoptosis pathways. Meanwhile, miR-122 and miR-132 are involved in two oxidative stress pathways.

Biomarkers of the Complement System Activation (C3a, C5a, sC5b-9) in Serum of Patients before and after Liver Transplantation.

The liver has a huge impact on the functioning of our body and the preservation of homeostasis. It is exposed to many serious diseases, which may lead to the chronic failure of this organ, which is becoming a global health problem today. Currently, the final form of treatment in patients with end-stage (acute and chronic) organ failure is transplantation. The proper function of transplanted organs depends on many cellular processes and immune and individual factors. An enormous role in the process of acceptance or rejection of a transplanted organ is attributed to, among others, the activation of the complement system. The aim of this study was the evaluation of the concentration of selected biomarkers' complement system activation (C3a, C5a, and sC5b-9 (terminal complement complex)) in the serum of patients before and after liver transplantation (24 h, two weeks). The study was conducted on a group of 100 patients undergoing liver transplantation. There were no complications during surgery and no transplant rejection in any of the patients. All patients were discharged home 2-3 weeks after the surgery. The levels of all analyzed components of the complement system were measured using the ELISA method. Additionally, the correlations of the basic laboratory parameters-C-reactive protein (CRP), hemoglobin (Hb), total bilirubin, alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGTP), and albumin-with the parameters of the complement system (C3a, C5a, and sC5b-9) were determined. In our study, changes in the concentrations of all examined complement system components before and after liver transplantation were observed, with the lowest values before liver transplantation and the highest concentration two weeks after. The direct increase in components of the complement system (C3a, C5a, and sC5b-9) 24 h after transplantation likely affects liver damage after ischemia-reperfusion injury (IRI), while their increase two weeks after transplantation may contribute to transplant tolerance. Increasingly, attention is being paid to the role of C3a and CRP as biomarkers of damage and failure of various organs. From the point of view of liver transplantation, the most interesting correlation in our own research was found exactly between CRP and C3a, 24 h after the transplantation. This study shows that changes in complement activation biomarkers and the correlation with CRP in blood could be a prognostic signature of liver allograft survival or rejection.

Digital PCR (dPCR) Quantification of miR-155-5p as a Potential Candidate for a Tissue Biomarker of Inflammation in Rabbits Infected with Lagovirus europaeus/Rabbit Hemorrhagic Disease Virus (RHDV).

MicroRNAs (miRNAs, miRs) are a group of small, 17-25 nucleotide, non-coding RNA sequences that, in their mature form, regulate gene expression at the post-transcriptional level. They participate in many physiological and pathological processes in both humans and animals. One such process is viral infection, in which miR-155 participates in innate and adaptive immune responses to a broad range of inflammatory mediators. Recently, the study of microRNA has become an interesting field of research as a potential candidate for biomarkers for various processes and disease. To use miRNAs as potential biomarkers of inflammation in viral diseases of animals and humans, it is necessary to improve their detection and quantification. In a previous study, using reverse transcription real-time quantitative PCR (RT-qPCR), we showed that the expression of ocu-miR-155-5p in liver tissue was significantly higher in rabbits infected with Lagovirus europaeus/Rabbit Hemorrhagic Disease Virus (RHDV) compared to healthy rabbits. The results indicated a role for ocu-miR-155-5p in Lagovirus europaeus/RHDV infection and reflected hepatitis and the impairment/dysfunction of this organ during RHD. MiR-155-5p was, therefore, hypothesized as a potential candidate for a tissue biomarker of inflammation and examined in tissues in Lagovirus europaeus/RHDV infection by dPCR. The objective of the study is the absolute quantification of ocu-miR-155-5p in four tissues (liver, lung, kidney, and spleen) of rabbits infected with Lagovirus europaeus/RHDV by digital PCR, a robust technique for the precise and direct quantification of small amounts of nucleic acids, including miRNAs, without standard curves and external references. The average copy number/µL (copies/µL) of ocu-miRNA-155-5p in rabbits infected with Lagovirus europaeus GI.1a/Rossi in the liver tissue was 12.26 ± 0.14, that in the lung tissue was 48.90 ± 9.23, that in the kidney tissue was 16.92 ± 2.89, and that in the spleen was 25.10 ± 0.90. In contrast, in the tissues of healthy control rabbits, the average number of copies/µL of ocu-miRNA-155-5p was 5.07 ± 1.10 for the liver, 23.52 ± 2.77 for lungs, 8.10 ± 0.86 for kidneys, and 42.12 ± 3.68 for the spleen. The increased expression of ocu-miRNA-155-5p in infected rabbits was demonstrated in the liver (a fold-change of 2.4, p-value = 0.0003), lung (a fold-change of 2.1, p-value = 0.03), and kidneys (a fold-change of 2.1, p-value = 0.01), with a decrease in the spleen (a fold-change of 0.6, p-value = 0.002). In the study of Lagovirus europaeus/RHDV infection and in the context of viral infections, this is the first report that shows the potential use of dPCR for the sensitive and absolute quantification of microRNA-155-5p in tissues during viral infection. We think miR-155-5p may be a potential candidate for a tissue biomarker of inflammation with Lagovirus europaeus/RHDV infection. Our report presents a new path in discovering potential candidates for the tissue biomarkers of inflammation.

The Influence of Circadian Rhythm on the Activity of Oxidative Stress Enzymes.

The circadian system synchronizes daily with the day-night cycle of our environment. Disruption of this rhythm impacts the emergence and development of many diseases caused, for example, by the overproduction of free radicals, leading to oxidative damage of cellular components. The goal of this study was to determine the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione transferase (GST), glutathione reductase (R-GSSG), and the concentration of glutathione (GSH) in the circadian rhythm. The study group comprised 66 healthy volunteers (20-50 years; 33 women; 33 men). The blood was collected at 2, 8 a.m., and 2, 8 p.m. All samples marked the serum melatonin concentration to confirm the correct sleeping rhythm and wakefulness throughout the day. The activity of study enzymes and the concentration of GSH were measured by the spectrophotometric method. Confirmed the existence of circadian regulation of oxidative stress enzymes except for GST activity. The peak of activity of study enzymes and GSH concentration was observed at 2 a.m. The increased activity of enzymes and the increase in GSH concentration observed at night indicate that during sleep, processes allowing to maintain of the redox balance are intensified, thus limiting the formation of oxidative stress.

Microbiota in sports.

The influence of microbiota on the human body is currently the subject of many studies. The composition of bacteria colonizing the gastrointestinal tract varies depending on genetic make-up, lifestyle, use of antibiotics or the presence of diseases. The diet is also important in the species diversity of the microbiota. This study is an analysis of the relationships between physical activity, diet, and the microbiota of the gastrointestinal tract in athletes. This review shows the differences in the microbial composition in various sports disciplines, the influence of probiotics on the microbiome, the consequence of which may be achieved even better sports results. Physical activity increases the number of bacteria, mainly of the Clostridiales order and the genus: Lactobacillus, Prevotella, Bacteroides, and Veillonella, and their number varies depending on the sports discipline. These bacteria are present in athletes in sports that require a high VO2 max. The players' diet also influences the composition of the microbiota. A diet rich in dietary fiber increases the amount of Lactobacillus or Bifidobacterium bacteria, probiotic microorganisms, which indicates the need to supplement the diet with probiotic preparations. It is impossible to suggest an unambiguous answer to how the microbiota of the gastrointestinal tract changes in athletes and requires further analyzes.

Association of Aneurysm Tissue Neutrophil Mediator Levels with Intraluminal Thrombus Thickness in Patients with Abdominal Aortic Aneurysm.

An intraluminal thrombus (ILT), which accumulates large numbers of neutrophils, plays a key role in abdominal aortic aneurysm (AAA) pathogenesis. This study aimed to compare levels of selected neutrophil inflammatory mediators in thick and thin ILT, plus adjacent AAA walls, to determine whether levels depend on ILT thickness. Neutrophil mediator levels were analysed by enzyme-linked immunosorbent assays in thick and thin segments of ILT, plus adjacent aneurysm wall sections, taken from one aneurysm sac each from 36 AAA patients. In aneurysmal walls covered by thick ILT, neutrophil elastase and TNF-a levels were significantly higher, as were concentrations of IL-6, in thick ILT compared to thin layers. Positive correlations of NGAL, MPO, and neutrophil elastase were observed between thick ILT and the adjacent wall and thin ILT and the adjacent wall, suggesting that these mediators probably infiltrate thick AAA compartments as well as thin. These observations might support the idea that neutrophil mediators and inflammatory cytokines differentially accumulate in AAA tissues according to ILT thickness. The increased levels of neutrophil mediators within thicker AAA segments might suggest the existence of an intensified proinflammatory state that in turn presumably might preferentially weaken the AAA wall at that region.

Assessment of Platelet Reactivity and Inflammatory Markers in Coronary Artery Bypass Graft Patients Treated with Acetylsalicylic Acid with Flavonoid Supplementation.

The recommended pharmacological therapy for patients with coronary artery disease (CAD) treated by coronary artery bypass grafting (CABG) is acetylsalicylic acid (ASA). To improve the antiplatelet effect, supplementation with flavonoids is also recommended. The aim of this study was to estimate anti-aggregation properties of diosmin, in combination with ASA, pre- and postoperatively and assess the relationship of this therapy with inflammatory processes in CAD patients undergoing CABG. The study patients (n = 26) took diosmin (1000 mg/day); the control patients (n = 27) took a placebo. The therapeutic period for taking diosmin was from at least 30 days before to 30 days after CABG. All patients also took 75 mg/day ASA. Platelet aggregation and IL-6, CRP, and fibrinogen concentrations were determined before and 30 days after surgery. Results showed that diosmin did not enhance the anti-aggregation effect of ASA at any assessment time. However, there was a stronger anti-aggregation effect 30 days after surgery that was diosmin independent and was associated with acute-phase markers in the postoperative period. Increased levels of inflammatory markers in the late phase of the postoperative period may provide an unfavorable prognostic factor in long-term follow-up, which should prompt the use of stronger antiplatelet therapy in patients after CABG.

Reference Values of D-Dimers and Fibrinogen in the Course of Physiological Pregnancy: the Potential Impact of Selected Risk Factors-A Pilot Study.

Pregnancy predisposes to thrombotic hemostasis, reflected in the laboratory as, e.g., increased levels of D-Dimers and fibrinogen, but in physiological pregnancy, the risk of venous thrombosis does not increase. Risk may increase if gestational diabetes mellitus (GDM) or nicotinism coexists. Study aims were to determine reference values for D-Dimers and fibrinogen concentrations in each trimester of pregnancy, corrected for GDM and nicotinism. Subjects and Methods. The study involved 71 pregnant women aged 25-44 y. Venous blood was collected three times: in the first (11-14 weeks), second (20-22 weeks), and third (30-31 weeks) trimesters. D-Dimer concentrations were determined by an enzyme-linked fluorescence assay, fibrinogen concentrations by a coagulation method according to Clauss. Results. Significant increases in D-Dimers and fibrinogen concentrations were observed, increasing with successive trimesters (p ANOVA < 0.0001). Furthermore, a positive correlation between D-Dimers and fibrinogen was detected in the second trimester of pregnancy (r = 0.475; p < 0.0001). In addition, a significantly higher fibrinogen concentration was found in women with GDM compared to without GDM (p = 0.0449). Reference ranges for D-Dimers were established, in trimester order, as follows: 167-721 ng/mL, 298-1653 ng/mL, and 483-2256 ng/mL. After adjusting for risk factors, significantly higher D-Dimer values (mainly second and third trimesters) were obtained: 165-638 ng/mL, 282-3474 ng/mL, and 483-4486 ng/mL, respectively. Reference ranges for fibrinogen were, in trimester order, 2.60-6.56 g/L, 3.40-8.53 g/L, and 3.63-9.14 g/L and, after adjustment for risk factors, 3.34-6.73 g/L, 3.40-8.84 g/L, and 3.12-9.91 g/L. Conclusions. We conclude that the increase in D-Dimers and fibrinogen levels in women with physiological pregnancy was compounded by gestational diabetes (GDM) and nicotinism. Therefore, D-Dimers and fibrinogen pregnancy reference values require correction for these risk factors.

Tissue factor levels and the fibrinolytic system in thin and thick intraluminal thrombus and underlying walls of abdominal aortic aneurysms.

BACKGROUND: The hemostatic system cooperates with proteolytic degradation in processes allowing abdominal aortic aneurysm (AAA) formation. In previous studies, it has been suggested that aneurysm rupture depends on intraluminal thrombus (ILT) thickness, which varies across each individual aneurysm. We hypothesized that hemostatic components differentially accumulate in AAA tissue in relation to ILT thickness. Thick (A1) and thin (B1) segments of ILTs and aneurysm wall sections A (adjacent to A1) and B (adjacent to B1) from one aneurysm sac were taken from 35 patients undergoing elective repair. METHODS: Factor levels were measured using enzyme-linked immunosorbent assay of protein extract. RESULTS: Tissue factor (TF) activities were significantly higher in thinner segments of AAA (B1 vs A1, P = .003; B vs A, P < .001; B vs A1, P < .001; B vs B1, P = .001). Significantly higher tissue plasminogen activator was found in thick thrombus-covered wall segments (A) than in B, A1, and B1 (P = .015, P < .001, and P < .001, respectively). Plasminogen concentrations were highest in ILT. Concentrations of α2-antiplasmin in thin ILT adjacent walls (B) were higher compared with wall (A) adjacent to thick ILT (P = .021) and thick ILT (A1; P < .001). Significant correlations between levels of different factors were mostly found in thick ILT (A1). However, no correlations were found at B sites, except for a correlation between plasmin and TF activities (r = 0.55; P = .004). CONCLUSIONS: These results suggest that higher TF activities are present in thinner AAA regions. These parameters and local fibrinolysis may be part of the processes leading to destruction of the aneurysm wall.

Homocysteine-Enhanced Proteolytic and Fibrinolytic Processes in Thin Intraluminal Thrombus and Adjacent Wall of Abdominal Aortic Aneurysm: Study In Vitro.

Homocysteine (Hcy) may affect the pathogenesis of abdominal aortic aneurysms (AAAs) through enhancement of proteolysis and an impaired coagulation/fibrinolysis system. Intensified haemostatic capacity may promote local proteolytic degradation of the aortic wall. This study aimed to examine the effects of Hcy on haemostatic and proteolytic processes in samples of thick and thin fragments of the ILT and underlying walls. Subjects and Methods. Thirty-six patients who underwent AAA surgery were enrolled. Aneurysm tissue sections were incubated with DL-Hcy (100 and 500 µmol/L) in a series of experiments and analyzed for concentration/activity of proteolytic and haemostatic markers by enzyme-linked immunosorbent assay. Results. Incubation of wall underlying thin ILT segments (B) with DL-Hcy resulted in an increase of active MMP-2 levels compared to control tissue (9.54 ± 5.88 versus 7.44 ± 4.48, p=0.011). DL-Hcy also induced t-PA and plasminogen concentration increases in thin thrombus sections (B1) compared to control tissue (respectively: 1.39 ± 1.65 versus 0.84 ± 0.74, p=0.024; 11.64 ± 5.05 versus 10.34 ± 5.52, p=0.018). In contrast, wall adjacent to thick thrombus segments (A) showed decreases in MMP-2 and TF activities compared to control (respectively, 5.89 ± 3.39 versus 7.26 ± 5.49, p=0.046; 67.13 ± 72.59 versus 114.46 ± 106.29, p=0.007). In thick ILT sections (A1), DL-Hcy decreased MMP-2 activity and t-PA and plasminogen concentrations compared to control tissue (respectively, 2.53 ± 2.02 versus 3.28 ± 2.65, p=0.006; 0.67 ± 0.57 versus 0.96 ± 0.91, p=0.021; 9.25 ± 4.59 versus 12.63 ± 9.56, p=0.017). In addition, analysis revealed positive correlations at all sites between activities/concentrations of MMP-2, TF, and PAI-1 measured in control tissues and after incubation with DL-Hcy. Conclusions. These data indicate the potential for excess Hcy to enhance damage of arterial wall in thinner AAA segments as a result of the increased activity of MMP-2 and fibrinolytic factors.

Factors influencing multiplate whole blood impedance platelet aggregometry measurements, during aspirin treatment in acute ischemic stroke: a pilot study.

Among patients with stroke, the phenomenon of resistance to treatment with low-dose aspirin acetylsalicylic acid (ASA) is quite common. The study included 133 patients hospitalized with acute ischemic stroke. Impedance platelet aggregometry (IPA) and levels of vWF and thromboxane (TXB2) were assessed - with the efficacy of aspirin in daily clinical investigation. Responses to treatment with doses of 150 and 300 mg/day were measured. In addition, we analyzed the response of proinflammatory factors [fibrinogen, C-reactive protein (CRP), white blood corpuscles (WBC)], lipids and hemoglobin A1c, which may alter platelet aggregation response to treatment. After a week of treatment at 150 mg/day, ASA patients were classified as laboratory resistant (42%) or sensitive (58%). Values of IPA in the resistant group were significantly higher (472 ±â€Š150 vs. 222 ±â€Š59 AUC, P < 0.0001). In resistant patients were also found higher levels of fibrinogen (3.90 ±â€Š0.89 vs. 3.46 ±â€Š0.74 g/l, P = 0.0046), CRP (6.97 ±â€Š5.66 vs. 4.17 ±â€Š4.03 mg/l, P = 0.0011), WBC (9.2 ±â€Š2.4 vs. 8.3 ±â€Š2.2 × 10/l, P = 0.0207) and lower HDL cholesterol (46 ±â€Š12 vs. 52 ±â€Š15 mg/dl, P = 0.016). This research shows that aspirin resistance assessment by IPA well reflects the clinical status of patients and should be used routinely. Resistance generally fails to 'break' at higher doses, hence our suggestion that patients resistant to low doses of the drug immediately switch to a thienopyridine class antiplatelet agent, for example, clopidogrel.

Conjugated linoleic acid isomers may diminish human macrophages adhesion to endothelial surface.

Dysfunction of endothelial cells and activation of monocytes in the vascular wall are important pathogenetic factors of atherosclerosis. Conjugated linoleic acids (CLAs) can modulate the function of immune system in humans: reduce the concentration of atherogenic lipoproteins, and the intensity of inflammatory processes in the plasma. In this paper, we focus on macrophage's surface integrins (ß1 integrin CD49d/CD29-(VLA4); Mac-1 as well as endothelial human vein endothelial cell (HUVEC) surface adhesins: vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1)) expression in relation to CLA isomer used during cell culture. Both CLA isomers decreased expression of VLA-4 and Mac-1 on macrophages compared with control cells (cultured with bovine serum albumine (BSA) or oxidized form of low-density lipoproteins). cis-9, trans-11 CLA isomer reduced ICAM-1 and VCAM-1 expression on the endothelium surface. Strong tendency to reduce of adhesion of macrophages to HUVEC in the cells cultured with CLA isomers was observed. The potential role of cis-9, trans-11 CLA in the reduction of adhesion of macrophages to the HUVEC--one of the important steps in the inflammatory process, can be considerate. These mechanisms may contribute to the potent anti-atherosclerotic effects of CLA in vivo.

Conjugated linoleic acid regulates phosphorylation of PPARγ by modulation of ERK 1/2 and p38 signaling in human macrophages/fatty acid-laden macrophages.

Stimulation of macrophages by a variety fatty acids causes activation of MAP kinases (MAPKs). The consequences arising from down-regulation of MAPKs may be a limitation in the activity of PPARγ, which is modulated by a modification catalyzed by these kinases. Phosphorylation of MAP kinases-ERK1/2 and p38 as well as PPARγ was determined by real-time polymerase chain reaction and Western blotting in human macrophages cultured with conjugated linoleic acids (CLAs). We demonstrated that CLA isomers alter MAP kinase phosphorylation and PPARγ activation. Phosphorylation of ERK1/2 was diminished in cells cultivated with cis-9,trans-11 CLA, whereas phosphorylation of p38 was reduced by trans-10,cis-12 CLA. PPARγ was phosphorylated mainly by ERK1/2, and consequently, PPARγ phosphorylation was suppressed mainly by cis-9,trans-11 isomer. In human adipocytes, cis-9,trans-11 C 18:2 raised the activation of PPAR and several of its downstream target genes. We suggest that a similar process may also occur in human macrophages.

The character of haemostatic disorders and level of protein S-100 in acute ischaemic stroke can affect survival in the first week of follow-up: a pilot study.

Disorders of haemostasis which result in ischaemic stroke usually appear as thromboembolism in peripheral veins and the pulmonary circulation, and to a lesser extent as coagulopathy. The S-100 protein, a marker of stroke, correlates positively with the neurological deficit National Institutes of Health Stroke Scale (NIHSS). We adopted the hypothesis that early death of patients with acute ischaemic stroke can be explained by changes in blood coagulation and fibrinolysis. The study included 84 patients hospitalized with acute ischaemic stroke. Three groups were created: I (death between 1 and 2 days), II (death between 5 and 7 days) and III (with no deaths in hospital). We measured levels of fibrinogen, antithrombin, D-dimers, plasmin-antiplasmin complexes, plasminogen and clotting times (prothrombin time and activated partial thromboplastin time), platelet number, euglobulin clot lysis time (ECLTindex) and S-100 protein, C-reactive protein and white blood cells (WBCs). Group I had lower concentrations of fibrinogen compared to groups II (3.13 vs. 4.18, P<0.01) and III (3.13 vs. 3.77, P<0.02) and higher levels of D-dimers (3643 vs. 2278, P<0.05), higher concentrations of plasmin-antiplasmin complexes (1410 vs. 882, P=0.03) and a lower ECLTindex (152 vs. 219, P<0.02) when compared with group III. Group I also had higher concentrations of protein S-100 (2.09 vs. 0.61, P<0.001), higher NIHSS (18.0 vs. 13.2, P=0.073) and number of WBC (14.1 vs. 11.1, P<0.02) than in group III. The observed abnormalities in haemostasis, either found systemically or locally as cerebral microvascular thrombosis, may be factors potentially associated with death of patients with the shortest survival time.

Is there an association between angiotensin-converting enzyme gene polymorphism and functional activation of monocytes and macrophage in young patients with essential hypertension?

BACKGROUND: This study was undertaken to determine whether the phenotype of monocytes and monocyte-derived macrophages is more proatherogenic in young persons with arterial hypertension and whether this phenotype is affected by smoking or polymorphism of the angiotensin-converting enzyme (ACE) gene. METHODS: We enrolled 40 young patients (24.1 +/- 4.7 years) with previously untreated arterial hypertension and 40 age-matched healthy controls. There were 20 smokers and 20 non-smokers in each group. RESULTS: In the hypertensive group, we found enhanced monocyte expression of CD11a (P < 0.001), reduced expression of CD49d (P < 0.001) and CD62L (P < 0.005), greater oxidative stress in resting and phorbol-12-mistrate-13-acetate-stimulated monocytes (P < 0.001), enhanced adhesion of monocytes to endothelial cells (P < 0.001), greater expression of CD36 on monocyte-derived macrophages (P < 0.001), and enhanced production of reactive oxygen species by resting and phorbol-12-mistrate-13-acetate-stimulated macrophages (P < 0.001). Cigarette smoking by hypertensive patients was associated with enhanced (P < 0.002) CD11a expression. There were no associations of ACE gene polymorphism with cellular expression or reactive oxygen species production studied among hypertensive patients. Only CD62L expression in DD homozygote participants was higher (P < 0.039) than in II homozygote participants. CONCLUSIONS: It is concluded that arterial hypertension affects the function of monocytes/macrophages in young persons. Polymorphism of the ACE gene is without effect on the functional activation of monocytes and macrophages.

[The effect of short-chain fatty acids on expression of endothelial adhesion molecules stimulated by oxidatively modified LDL]. / Wplyw krótkolancuchowych kwasów tluszczowych na stymulowana zmodyfikowanymi oksydacyjnie ldl ekspresje sródblonkowych czastek adhezyjnych.

INTRODUCTION: Adhesion and migration of mononuclear leukocytes into the vascular wall is a crucial step in atherogenesis. Expression of cell adhesion molecules by endothelial cells plays a leading role in this process. Natural short-chain fatty acids produced by bacterial fermentation of dietary fiber have been attributed with antiatherogenic properties. MATERIAL AND METHODS: This in vitro study has been conceived in an attempt to shed light on the mechanisms responsible for the modulatory effect of short-chain fatty acids in atherogenesis. The following conclusions have been drawn. Butyrate and propionate are selective inhibitors of ox-LDL-stimulated VCAM-1 and ICAM-1 expression with a mechanism of action involving reduced protein and specific mRNA production through inhibition of NF-kappaB activation. Suppressed expression of VCAM-1 and ICAM-1 was associated with reduced adherence of monocytes and lymphocytes to ox-LDL stimulated endothelial cells. RESULTS: Butyrate and propionate may have anti-inflammatory and antiatherogenic properties partly attributable to an inhibitory effect on NF-kappaB activation.

Butyrate inhibits cytokine-induced VCAM-1 and ICAM-1 expression in cultured endothelial cells: the role of NF-kappaB and PPARalpha.

Adhesion and migration of leukocytes into the surrounding tissues is a crucial step in inflammation, immunity, and atherogenesis. Expression of cell adhesion molecules by endothelial cells plays a leading role in this process. Butyrate, a natural short-chain fatty acid produced by bacterial fermentation of dietary fiber, has been attributed with anti-inflammatory activity in inflammatory bowel disease. Butyrate in vitro is active in colonocytes and several other cell types. We have studied the effect of butyrate on expression of endothelial leukocyte adhesion molecules by cytokine-stimulated human umbilical vein endothelial cells (HUVEC). Pretreatment of HUVEC with butyrate-inhibited tumor necrosis factor-alpha (TNFalpha)-induced expression of vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1) in a time and concentration-dependent manner. Butyrate at 10 mM/L inhibited interleukin-1 (IL-1)-stimulated VCAM-1 and ICAM-1 expression. The effect of butyrate on cytokine-stimulated VCAM-1 expression was more pronounced than in the case of ICAM-1. Butyrate decreased TNFalpha-induced expression of mRNA for VCAM-1 and ICAM-1. Suppressed expression of VCAM-1 and ICAM-1 was associated with reduced adherence of monocytes and lymphocytes to cytokine-stimulated HUVEC. Butyrate inhibited TNFalpha-induced activation of nuclear factor-kappaB (NF-kappaB) in HUVEC. Finally, butyrate enhanced peroxisome proliferator-activated receptor-alpha (PPARalpha) expression in HUVEC. These results demonstrate that butyrate may have anti-inflammatory properties not only in colonocytes but also in endothelial cells. The anti-inflammatory and (perhaps) antiatherogenic properties of butyrate may partly be attributed to an effect on activation of NF-kappaB and PPARalpha and to the associated expression of VCAM-1 and ICAM-1. The present findings support further investigations on the therapeutic benefits of butyrate in several pathological events involving leukocyte recruitment.

[The role of modified oxidation of low density lipoprotein in pathognesis of atherosclerosis]. / Rola zmodyfikowanych oksydacyjnie lipoprotein malej gestosci w patogenezie miazdzycy.

The precise mechanisms of LDL oxidation in vivo are not well-known but the presence of several enzymes and agents capable of modifying LDL particles was noted in arterial wall. These reactive agents modify lipid, protein as well as antioxidant component of the LDL particles. Postsecretory modification in LDL structure trigger its atherogenic potential. LDL particles retained in the artery wall interact with the various forms of proteoglycans in the extracellular matrix, that increases the resident time of LDL in endothelial space and allows extensive modification. The modified forms of LDL are able to activate intimal cells and to trigger various inflammatory signals. In turn, activated intimal cells can secrete enzymes and agents capable of modifying LDL. These processes can initiate and maintain a vicious circle in the intima and lead to lesion progression.

Protective properties of artichoke (Cynara scolymus) against oxidative stress induced in cultured endothelial cells and monocytes.

It is currently believed that oxidative stress and inflammation play a significant role in atherogenesis. Artichoke extract exhibits hypolipemic properties and contains numerous active substances with antioxidant properties in vitro. We have studied the influence of aqueous and ethanolic extracts from artichoke on intracellular oxidative stress stimulated by inflammatory mediators (TNFalpha and LPS) and ox-LDL in endothelial cells and monocytes. Oxidative stress which reflects the intracellular production of reactive oxygen species (ROS) was followed by measuring the oxidation of 2', 7'-dichlorofluorescin (DCFH) to 2', 7'-dichlorofluorescein (DCF). Agueous and ethanolic extracts from artichoke were found to inhibit basal and stimulated ROS production in endothelial cells and monocytes in dose dependent manner. In endothelial cells, the ethanolic extract (50 microg/ml) reduced ox-LDL-induced intracellular ROS production by 60% (p<0,001) while aqueous extract (50 microg/ml) by 43% (p<0,01). The ethanolic extract (50 microg/ml) reduced ox-LDL-induced intracellular ROS production in monocytes by 76% (p<0,01). Effective concentrations (25-100 microg/ml) were well below the cytotoxic levels of the extracts which started at 1 mg/ml as assessed by LDH leakage and trypan blue exclusion. Penetration of some active substances into the cells was necessary for inhibition to take place as juged from the effect of preincubation time. These results demonstrate that artichoke extracts have marked protective properties against oxidative stress induced by inflammatory mediators and ox-LDL in cultured endothelial cells and monocytes.