LOX-1 variants modulate the severity of cardiovascular disease: state of the art and future directions.

Atherosclerosis is one of the major causes of cerebral infarction and many other ischemic cardio-cerebrovascular diseases. Although large randomized clinical trials have highlighted the impressive benefits of lipid-lowering therapies, the 50-70% of patients who have achieved their lipid-lowering goal remain at high cardiovascular disease risk. For this reason, there is a need to investigate other markers of atherosclerosis progression. LOX-1 is a scavenger receptor that accepts oxidized low-density lipoproteins as major ligand and internalizes it by endocytosis favoring its retention in subendothelial layer and triggering a wide variety of proatherogenic events. However, other factors such as cytokines, shear stress, and advanced glycation end-products can upregulate LOX-1. LOX-1 is encoded by the OLR1 gene, located in the p12.3-p13 region of chromosome 12. OLR1 gene has different isoforms induced by splicing, or single-nucleotide polymorphisms (SNPs). According to some authors, the expression of these isoforms induces a different effect on atherosclerosis and cardiovascular disease. In particular, LOXIN, an isoform lacking part of the functional domain, exerts an important role in atherosclerosis protection. In other cases, studies on SNPs showed an association with more severe forms, like in the case of 3'UTR polymorphisms. The knowledge of these variants can give rise to the development of new preventive therapies and can lead to the identification of subjects at greater risk of cardiovascular event. In this review, we reported the state of the art regarding SNPs with known effects on OLR1 splicing and how LOX-1 variants modulate the severity of cardiovascular disease.

Classes of Lipid Mediators and Their Effects on Vascular Inflammation in Atherosclerosis.

It is commonly believed that the inactivation of inflammation is mainly due to the decay or cessation of inducers. In reality, in connection with the development of atherosclerosis, spontaneous decay of inducers is not observed. It is now known that lipid mediators originating from polyunsaturated fatty acids (PUFAs), which are important constituents of all cell membranes, can act in the inflamed tissue and bring it to resolution. In fact, PUFAs, such as arachidonic acid (AA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), are precursors to both pro-inflammatory and anti-inflammatory compounds. In this review, we describe the lipid mediators of vascular inflammation and resolution, and their biochemical activity. In addition, we highlight data from the literature that often show a worsening of atherosclerotic disease in subjects deficient in lipid mediators of inflammation resolution, and we also report on the anti-proteasic and anti-thrombotic properties of these same lipid mediators. It should be noted that despite promising data observed in both animal and in vitro studies, contradictory clinical results have been observed for omega-3 PUFAs. Many further studies will be required in order to clarify the observed conflicts, although lifestyle habits such as smoking or other biochemical factors may often influence the normal synthesis of lipid mediators of inflammation resolution.

Status of biomarkers for the identification of stable or vulnerable plaques in atherosclerosis.

Atherosclerosis is a systemic inflammation of the arteries characterized by atherosclerotic plaque due to the accumulation of lipids, inflammatory cells, apoptotic cells, calcium and extracellular matrix (ECM) proteins. Stable plaques present a chronic inflammatory infiltration, whereas vulnerable plaques present an 'active' inflammation involved in the thinning of the fibrous cap that predisposes to plaque rupture. Several complex biological cellular processes lead plaques to evolve from stable to vulnerable predisposing them to rupture and thrombosis. In this review, we analyze some emerging circulating biomarkers related to inflammation, ECM and lipid infiltration, angiogenesis, metalloproteinases and microRNA (miRNA), as possible diagnostic and prognostic indicators of plaque vulnerability.

Role of oxidative stress-related biomarkers in heart failure: galectin 3, α1-antitrypsin and LOX-1: new therapeutic perspective?

Heart failure (HF) is considered one of the most common diseases and one of the major causes of death. The latest studies show that HF is associated with an increase in oxidative stress. The use of antioxidants as therapy is effective in animal models, but not in humans. In this review, we analyse some emerging markers related to oxidative stress, evaluating their possible use as therapeutic targets: galectin-3, a ß galactoside associated with myocardial fibrosis, α1-antitrypsin, an antiprotease and lectin-like oxidized low-density-lipoprotein receptor-1, the major receptor for ox-LDL. The up-regulation of galectin-3 appears to be associated with HF, atrial fibrillation, dilated cardiomyopathy, fibrogenesis and mortality, while in other cases it seems that galectin-3 may be protective in ischaemia-reperfusion injury. Serum α1-antitrypsin protein levels may increase in the presence of high concentrations of serum proteases, which are over expressed during reperfusion. The overexpression of α1-antitrypsin or the exogenous α1-antitrypsin treatment exhibits an anti-oxidative stress role, evaluated by increased eNOS expression and by decreased MMP9 expression, implicated in HF. The cardiac lectin-like oxidized low-density-lipoprotein receptor-1 is activated by oxidative stress in ischaemia-reperfusion injury, inducing apoptosis in cardiomyocytes through the deleterious NF-kB pathway, while the administration of anti-lectin-like oxidized low-density-lipoprotein receptor-1 antibody suppresses apoptosis and reduces the extent of myocardial infarction. In conclusion, α1-antitrypsin and lectin-like oxidized low-density-lipoprotein receptor-1 seem to represent two good markers in HF and therapeutic targets, whereas galectin-3 does not.

Traditional and new candidate cardiac biomarkers assessed before, early, and late after half marathon in trained subjects.

PURPOSE: Cardiac Troponins (cTnI, cTnT), NT-proBNP, and galectin-3 (GAL-3) mirror cardiomyocyte injury, stretch, and fibrosis. However, although these biomarkers has been thoroughly studied in marathon or ultramarathon, the effects occurring running shorter distances, as half-marathon, are less known and data are generally limited to immediately post-race evaluation. Moreover, significant variation of alpha-1 antitrypsin (AAT), an anti-protease factor with anti-inflammatory properties, has been recently observed in heart failure, but not investigated in paraphysiological settings. The aim of the study was to evaluate these biomarkers concentration and trends in trained runners before half-marathon run and during a 48-h recovery period. METHODS: In 18 half-marathon runners (15 males, 46 ± 6 years), cTnI, GAL-3 (Architect, Abbott), cTnT, NT-proBNP (Cobas e411, Roche), and AAT (Abcam, Cambridge, UK) were evaluated at rest, immediately post-run, and at 24 and 48-h recovery period. RESULTS: cTnT, NT-proBNP, and GAL-3 transiently increased after post-race, but normalized at 24 h (GAL-3 p < 0.01, cTnT < 0.001) or 48 h (NT-proBNP < 0.001), while cTnI and AAT did not significantly change. The frequency of values exceeding the diagnostic threshold, as evaluated at baseline and after the race, did not differ for cTnI ([Formula: see text] = 1.1, p = ns), and NT-proBNP ([Formula: see text] = 6, p = ns), but significantly increased for cTnT ([Formula: see text] = 23, p < 0.001) and GAL-3 ([Formula: see text] = 6.3, p < 0.05). None of the subjects showed AAT values exceeding the reference range at baseline and at any of the time points after the race. CONCLUSION: The transient cTnT, NT-proBNP, and GAL-3 increase may suggest a temporary stress on the myocyte. However, being the increase of all biomarkers moderate and reversible, it may represent a physiological response to acute exercise.

Roles of LOX-1 in microvascular dysfunction.

Studies from human and animal models with metabolic disease and hypertension highlight atrophic remodeling, reduced lumen size and thinner vascular walls of microvessels with profound density reduction. This impaired vascular response limits the perfusion of peripheral tissues inducing organ damage. These conditions are strongly associated with oxidative stress and in particular with the up-regulation of lectin-like oxidized low density lipoprotein receptor-1 (LOX-1). Several factors such as cytokines, shear stress, and advanced glycation end-products, especially oxLDL, can up-regulate LOX-1. The activation of this receptor induces the production of adhesion molecules, cytokines and the release of reactive oxygen species via NADPH oxidase. LOX-1 is considered a potent mediator of endothelial dysfunction and it is significantly associated with reduced microvascular endothelium NO-dependent vasodilation in hypercholesterolemia and hypertension. Microvascular endothelial cells increased the expression of IL-6 in association with the increased concentration of LDL and its degree of oxidation. Moreover, increased IL-6 levels are associated with up-regulation of LOX-1 in a dose-dependent manner. Another consequence of microvascular inflammation is the generation of small amounts of ROS, similar to those induced by low concentration of oxLDL (<5 µg/mL) which induces capillary tube formation of endothelial cells, through LOX-1 up-regulation. In light of its central role, LOX-1 represents an attractive therapeutic target for the treatment of human atherosclerotic diseases and microvascular disorders.

A fermented bean flour extract downregulates LOX-1, CHOP and ICAM-1 in HMEC-1 stimulated by ox-LDL.

This study focused on an extract from fermented flour from the Lady Joy variety of the common bean Phaseolus vulgaris. The extract, Lady Joy lysate (Lys LJ), is enriched in antioxidant compounds during the fermentation. We assessed it for its protective effect on endothelial cells treated with oxidized-LDL (ox-LDL). The oxidative stress was determined by measuring the contents of thiobarbituric acid-reactive substances and reactive oxygen metabolites. ICAM-1, ET-1 and IL-6 concentrations were assessed using ELISA. LOX-1 and CHOP expression were analyzed using both quantitative RT-PCR and ELISA or western blotting. Ox-LDL treatment induced significant oxidative stress, which was strongly reduced by pre-treatment with the extract. The ox-LDL exposure significantly enhanced ICAM-1, IL-6 and ET-1 levels over basal levels. Lys LJ pre-treatment exerted an inhibitory effect on ox-LDL-induced endothelial activation with ICAM-1 levels comparable to those for the untreated cells. IL-6 and ET-1 production, although reduced, was still significantly higher than for the control. Both LOX-1 and CHOP expression were upregulated after ox-LDL exposure, but this effect was significantly decreased after Lys LJ pre-treatment. Lys LJ alone did not alter the ICAM-1, IL-6 and ET-1 concentrations or CHOP expression, but it did significantly lower the LOX-1 protein level. Our data suggest that Lys LJ is an effective antioxidant that is able to inhibit the oxidation process, but that it is only marginally active against inflammation and ET-1 production in HMEC-1 exposed to ox-LDL.

Thyroid hormone deiodinases D1, D2, and D3 are expressed in human endothelial dermal microvascular line: effects of thyroid hormones.

Endothelial system acts as a large endocrine organ in the human body; however, little is still known about the regulative role of THs on endothelial cells. Aim of the present study was to investigate the expression of the TH deiodinases (D1, D2, and D3) and TH receptors (TRα1, TRα2, and TRß1) in an endothelial microvascular cultured cell model (HMEC-1), after stimulation with triiodothyronine (T3, 10-100 nM), thyroxine (T4, 10-100 nM), and reverse T3 (rT3, 1-10 nM). DIO1 was significantly inhibited by T4 at 10 and 100 nM (p < 0.001). rT3 significantly inhibited DIO1 at 1 nM concentration (p < 0.01) and stimulated DIO1 at 10 nM dosage (p < 0.001). T4 and rT3 significantly inhibited DIO2 at all concentrations. DIO3 was induced at 100 nM T3 (p < 0.05) and 100 nM rT3 (p < 0.01), and TRα1 and TRα2 mRNAs were significantly increased after 100 nM T3 treatment (p < 0.05) and decreased after 1 and 10 nM rT3 (p < 0.05). TRß1 was significantly increased by all THs at different concentrations: 10 nM T3 and 100 nM T3 (p < 0.05), 1 nM rT3 (p < 0.001), and 100 nM T4 (p < 0.01). D1 and D2 protein levels were evaluated, but no significant difference was observed for any hormonal treatment. For the first time, we found that the TH deiodinases and receptors are expressed in endothelial HMEC-1 cells. These findings might be of significant clinical relevance, given the important regulatory role of the endothelium as first barrier to the bloodstream.

Relationship among IL-6, LDL cholesterol and lipid peroxidation.

Previous studies evidenced a significant reduction in serum cholesterol levels during an episode of acute inflammation. The aim of the present study was to verify the hypothesis of a regulatory role of cytokines through an in vitro model that simulates a situation of vascular inflammation and high levels of LDL or lipoperoxides. Human microvascular endothelial cells-1 were used in all experiments. The cells were exposed for 24 h to increasing doses of LDL, oxidized lipoprotein, and 8-isoprostane (in the absence or presence of SQ29.548, a TXA2 receptor antagonist). Moreover, LDL receptor and oxidized lipoprotein receptor expression analyzed after endothelial cells' incubation with increasing doses of interleukin-6. The ELISA test and quantitative real-time PCR were performed. Endothelial cells showed a significant increase in interleukin-6 medium levels associated with LDL, oxidized LDL and with the degree of oxidation (absence or presence of SQ29.548), while 8-isoprostane did not. Treatment of human microvascular endothelial cells-1 for 24 h with increasing doses of interleukin-6 significantly enhanced LDL receptor and oxidized lipoprotein receptor-1 mRNA expression. Our data suggest the presence of a compensatory mechanism. The induction of a significant increase of IL-6 does not seem to be caused by the presence of the biological activity of 8-isoprostane.

LOX-1, a new marker of risk and prognosis in coronary artery disease?

The development of atherosclerosis is caused by the accumulation of lipid, inflammatory cytokine production, and the large amount of inflammatory cells in the arterial wall. It is now established that the presence of oxidized low-density lipoproteins (ox-LDL) has an important role in the pathogenesis of the disease. There are many scavenger receptors for ox-LDL, among which LOX-1 seems to be important for the induction of endothelial dysfunction and the other subsequent events that lead to the formation of atheromatous plaque. Our findings indicate the presence of a regulatory role induced by the presence of ox-LDL on LOX-1 through the amplification of IL-6 synthesis. This mechanism contributes to the upregulation of the ORL-1 gene expression in presence of risk factors. Many authors have shown the possibility to use LOX-1 as a good marker for the diagnosis and prognosis of coronary artery disease because it is easy to measure and more sensitive than other markers commonly used in the routine of laboratory medicine.

Interactions between immune, stress-related hormonal and cardiovascular systems following strenuous physical exercise.

Physical exercise represents a eustress condition that promotes rapid coordinated adjustments in the immune, stress-related hormonal and cardiovascular systems, for maintaining homeostasis in response to increased metabolic demands. Compared to the tight multisystem coordination during exercise, evidence of between-systems cross talk in the early post exercise is still lacking. This study was aimed at identifying possible interactions between multiple systems following strenuous physical exercise (Ironman race) performed by twenty well-trained triathletes. Cardiac hemodynamics, left ventricle systolic and diastolic function and heart rate variability were measured along with plasma concentrations of immune messengers (cytokines and C-reactive protein) and stress-related hormones (catecholamines and cortisol) both 24h before and within 20 min after the race. Observed changes in antiinflammatory pathways, stress-related hormones and cardiovascular function were in line with previous findings; moreover, correlating parameters' changes (post versus pre-race) highlighted a dependence of cardiovascular function on the post-race biohumoral milieu: in particular, individual post-race variations of heart rate and diastolic function were strongly correlated with individual variations of anti-inflammatory cytokines, while individual baroreflex sensitivity changes were linked to IL-8 increase. Multiple correlations between anti-inflammatory cytokines and catecholamines were also found according with the autonomic regulation of immune function. Observed post-race cytokine and hormone levels were presumptively representative of the increases reached at the effort end while the cardiovascular parameters after the race were measured during the cardiovascular recovery; thus, results suggest that sustained strenuous exercise produced a stereotyped cardiovascular early recovery, whose speed could be conditioned by the immune and stress-related hormonal milieu.

Chlamydomonas agloeformis from the Ecuadorian Highlands: Nutrients and Bioactive Compounds Profiling and In Vitro Antioxidant Activity.

Green microalgae are single-celled eukaryotic organisms that, in recent years, are becoming increasingly important in the nutraceutical, cosmetic, and pharmaceutical fields because of their high content of bioactive compounds. In this study, a particular green microalga was isolated from freshwater highland lakes of Ecuador and morphologically and molecularly identified as Chlamydomonas agloeformis (ChA), and it was studied for nutritional and nutraceutical properties. The phenolic composition and the fatty acids profile of lyophilized cells were determined. The methanolic extract was analyzed for the phenolic compounds profile and the antioxidant capacity by means of in vitro tests. Finally, Human Microvascular Endothelial Cells (HMEC-1) were exploited to explore the capacity of ChA to reduce the endothelial damage induced by oxidized LDL-mediated oxidative stress. The extract showed a good antioxidant ability thanks to the high content in polyphenolic compounds. The observed decrease in HMEC-1 cells endothelial damage also was probably due to the antioxidant compounds present in the extract. Based on the outcomes of our in vitro assays, ChA demonstrated to be a promising source of bioactive compounds possessing exceptional antioxidant capacities which make it a prospective functional food.

In Vitro Characterization of Antioxidant, Antibacterial and Antimutagenic Activities of the Green Microalga Ettlia pseudoalveolaris.

Recently, green microalgae have gained importance due to their nutritional and bioactive compounds, which makes them some of the most promising and innovative functional foods. The aim of this study was to evaluate the chemical profile and the in vitro antioxidant, antimicrobial and antimutagenic activity of an aqueous extract of the green microalga Ettlia pseudoalveolaris, obtained from the freshwater lakes of the Ecuadorian Highlands. Human microvascular endothelial cells (HMEC-1) were used to determine the ability of the microalga to reduce the endothelial damage caused by hydrogen peroxide-induced oxidative stress. Furthermore, the eukaryotic system Saccharomyces cerevisiae was used to evaluate the possible cytotoxic, mutagenic and antimutagenic effect of E. pseudoalveolaris. The extract showed a notable antioxidant capacity and a moderate antibacterial activity mostly due to the high content in polyphenolic compounds. It is likely that the antioxidant compounds present in the extract were also responsible for the observed reduction in endothelial damage of HMEC-1 cells. An antimutagenic effect through a direct antioxidant mechanism was also found. Based on the results of in vitro assays, E. pseudoalveolaris proved to be a good source of bioactive compounds and antioxidant, antibacterial and antimutagenic capacities making it a potential functional food.

Beneficial effect of Lisosan G on cultured human microvascular endothelial cells exposed to oxidised low density lipoprotein.

BACKGROUND & OBJECTIVES: Nutritional compounds which display anti-inflammatory and antioxidant effects have specific applications in preventing oxidative stress and endothelial dysfunction. In this study we evaluated the effect of Lisosan G (powder of Triticum sativum grains) on human microvascular endothelial cells (HMEC-1) exposed to oxidized low density lipoprotein (ox-LDL). METHODS: The protective effects of Lisosan G were evaluated on human microvascular endothelial cells exposed to ox-LDL. Intercellular adhesion molecular-1 (ICAM-1), endothelin-1 (ET-1), and interleukin-6 (IL-6) concentrations and the expression of the respective genes were evaluated in response to incubation with ox-LDL, after co-incubation with ox-LDL and Lisosan G or exposed to Lisosan G alone. The analysis of LOX-1 gene was performed with RT-PCR semi quantitative method. The degree of oxidation induced in relation to control, was established by measurement of malondialdehyde (MDA) production. RESULTS: The incubation with ox-LDL induced a significant increase in ICAM-1, IL-6 and ET-1 levels compared to the basal condition (P<0.01, P<0.05, and P<0.01, respectively), while in presence of Lisosan G, ICAM-1 levels showed a significant reduction both compared to the cultures treated with ox-LDL and control (P<0.01). IL-6 levels did not show any difference; ET-1 levels showed a partial reduction after co-treatment with Lisosan G, and also with Lisosan G alone, reduced the concentration below control (P<0.01). The modulation of these markers was confirmed by RT-PCR analysis. An association between MDA formation and the three markers production was observed. Semi-quantitative analysis of LOX-1 gene expression showed a significant up-regulation only after ox-LDL exposure. INTERPRETATION & CONCLUSIONS: The results demonstrate that Lisosan G may have an important role in the prevention of microcirculatory dysfunction.

Early subclinical increase in pulmonary water content in athletes performing sustained heavy exercise at sea level: ultrasound lung comet-tail evidence.

Whether prolonged strenuous exercise performed by athletes at sea level can produce interstitial pulmonary edema is under debate. Chest sonography allows to estimate extravascular lung water, creating ultrasound lung comet-tail (ULC) artifacts. The aim of the study was to determine whether pulmonary water content increases in Ironmen (n = 31) during race at sea level and its correlation with cardiopulmonary function and systemic proinflammatory and cardiac biohumoral markers. A multiple factor analysis approach was used to determine the relations between systemic modifications and ULCs by assessing correlations among variables and groups of variables showing significant pre-post changes. All athletes were asymptomatic for cough and dyspnea at rest and after the race. Immediately after the race, a score of more than five comet tail artifacts, the threshold for a significant detection, was present in 23 athletes (74%; 16.3 ± 11.2; P < 0.01 ULC after the race vs. rest) but decreased 12 h after the end of the race (13 athletes; 42%; 6.3 ± 8.0; P < 0.01 vs. soon after the race). Multiple factor analysis showed significant correlations between ULCs and cardiac-related variables and NH(2)-terminal pro-brain natriuretic peptide. Healthy athletes developed subclinical increase in pulmonary water content immediately after an Ironman race at sea level, as shown by the increased number of ULCs related to cardiac changes occurring during exercise. Hemodynamic changes are one of several potential factors contributing to the mechanisms of ULCs.

Cardiovascular risk in COVID-19 infection.

A few months ago a new coronavirus was identified in Cina officially named by the WHO as COVID-19. The thousands of patients who died showed pneumonia and alveolar damage, but actually, according to several authors in addition to the acute respiratory distress syndrome the virus can give rise to multiorgan failure. In fact, many people died equally despite being intubated and treated for respiratory failure. In this review, we especially wanted to describe the virus effects on the cardiovascular system, probably the leading cause of death of thousands of deceased patients. Therefore, mortality is indirectly induced by the virus through vascular inflammation and cardiovascular damage and patients with severe COVID-19 infection showed significantly increased levels of cardiac troponin I and inflammatory cytokines. The main activation of the signal pathways for the production of inflammatory cytokines are the toll-like receptors that recognize the presence of viral nucleic acids and the ACE-2 receptors, that the virus uses to infect the cells. The binding to ACE-2 also allows to promote high levels of angiotensin II by promoting high levels of blood pressure. High levels of IL-6, IL-1B and IL-8 have been associated with plaque instability and increased thrombotic risk. Furthermore IL-6 is involved in the stimulation of matrix-degrading enzymes such as matrix metalloproteinases, and may contribute to the development of acute coronary syndrome. In addition, TNF-α, IL-1 and IL-6 present in patients with severe COVID-19 are associated with coagulation activation and thrombin generation resulting in disseminated intravascular coagulation or thrombotic microangiopathy. Considering these pathological effects of the virus, anti-inflammatory and anticoagulant treatments are to be considered to avoid cardiovascular events. In this regard, heparin, in addition to its anticoagulant characteristics, has been shown to have good control over inflammation and to be a good anti-viral drug.

α-1 Antitrypsin as a potential biomarker in chronic heart failure.

BACKGROUND: Heart failure is characterized by a tissue damage that progressively leads to mechanical cardiac dysfunction and remodeling. A recent investigation showed that α-1 antitripsin, an antiprotease, able to inhibit metalloproteinases, provides prognostic information about heart failure and mortality postacute myocardial infarction. Therefore, we conducted a study to establish if α-1 antitrypsin (AAT) could be considered a marker of severity of heart failure. METHODS: A total of 182 heart failure patients (Group 1) were enrolled and AAT values were compared with controls (Group 2). RESULTS: In Group 1 a significant increment of AAT levels respect to Group 2 was observed (P < 0.0001). Moreover, in patients enrolled a progressive elevation of AAT levels across New York Heart Association classes (P < 0.0001) was found. Patients with α-1 antitripsin levels above median value showed lower hemoglobin concentration, higher circulating levels of C-reactive protein, hs-troponin T and B-type natriuretic peptide prohormone. Group 1 AAT levels resulted highly positively associated to B-type natriuretic peptide prohormone, C-reactive protein levels, while negatively associated to left ventricular ejection fraction%. However, at multivariate logistic analysis, only C-reactive protein was confirmed in a subgroup of postischemic heart failure patients. CONCLUSION: Adding AAT levels to the panel of heart failure biomarkers allow a better stratification of patients with heart failure.

TSH induces co-localization of TSH receptor and Na/K-ATPase in human erythrocytes.

Thyroid stimulating hormone (TSH) binds to a specific TSH receptor (TSHR) which activates adenylate cyclase and increases cAMP levels in thyroidal cells. Recent studies have reported the presence of TSH receptor in several extra-thyroidal cell types, including erythrocytes. We have previously suggested that TSH is able to influence the erythrocyte Na/K-ATPase ouabain binding properties through a receptor mediated mechanism. The direct interaction of TSH receptor with the Na/K-pump and a functional role of TSHR in erythrocytes was not demonstrated. The interaction of TSH receptor with Na/K-pump and a TSHR functional role are not yet demonstrated in erythrocytes. In this study, we examined the interaction between the two receptors after TSH treatment using immunofluorescence coupled to confocal microscopy and a co-immunoprecipitation technique. The cAMP dependent signalling after TSH treatment was measured to verify TSHR functionality. We found that TSH receptor and Na/K-ATPase are localized on the membranes of both erythrocytes and erythrocyte ghosts; TSH receptor responds to TSH treatment by increasing intracellular cAMP levels from two to tenfold. In ghost membranes TSH treatment enhances up to three fold co-localization of TSHR with Na/K-ATPase and co-immunoprecipitation confirms their direct physical interaction. In conclusion our results are compatible with the existence, in erythrocytes, of a functional TSHR that interacts with Na/K-ATPase after TSH treatment, thus suggesting a novel cell signalling pathway, potentially active in local circulatory control.

The Impact of Sourdough Fermentation on Non-Nutritive Compounds and Antioxidant Activities of Flours from Different Phaseolus Vulgaris L. Genotypes.

This study dealt with the effect of sourdough fermentation on antinutrients, phytochemicals, and antioxidant activities of flours from three Phaseoulus vulgaris L. genotypes with differing composition of lectins. Specifically, cultivar Lady Joy (LJ) devoid of phytohemagglutinin (PHA) and enriched in alfa-amylase inhibitor (αAI), breeding line P500 low in PHA and devoid of αAI, and Taylor's horticultivar, containing normal levels of both proteins. Sourdough fermentation positively affects the nutritional values of all bean flours by reducing some antinutrients, for example, phytic acid while preserving αAI activity. It significantly increased total polyphenols, flavonols, and ascorbic acid content, while reducing flavonoids. No significant differences in antioxidant activity, measured by in vitro and ex vivo assays on human erythrocytes, were found. The kinetic profiles of conjugated dienes analysis showed a strong inhibitory effect on low-density lipoproteins oxidation of all tested powders, with unfermented flours displaying the best antioxidant activity. Among bean powders, unfermented and fermented LJ showed the highest polyphenols level (4.21 ± 0.18 and 4.96 ± 0.15 mg GAE/g dw, respectively), oxygen radical absorbance capacity (ORAC) values (24.17 ± 0.14 and 24.02 ± 0.93 µmol TE/100g dw, respectively) and cellular antioxidant activity (71.6 ± 7.05 and 62.7 ± 3.3 units, respectively). Finally, since fermentation drastically reduces phytic acid content while preserving αAI activity, fermented LJ represents an important natural slimming supplement.

Emerging Biomarkers of Oxidative Stress in Acute and Stable Coronary Artery Disease: Levels and Determinants.

BACKGROUND: Oxidative stress is crucial in the pathogenesis of atherosclerosis and acute myocardial infarction (AMI). Under the generic terms "oxidative stress" (OS), many biomarkers belonging to different pathways have been proposed. AIM: To compare the levels of recently proposed OS-related parameters in acute coronary syndromes (ACS) and stable coronary artery disease (CAD), to evaluate their effectiveness as additive risk or illness indicators of stable and acute ischemic events, and their response over time during the course of AMI. METHODS: 76 ACS, 77 CAD patients, and 63 controls were enrolled in the study. Different OS-related biomarkers, including reactive oxygen metabolites (ROM), the total antioxidant capacity (OXY), nitrite/nitrate (final nitric oxide products, NOx), and Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), were evaluated. Moreover, time response during AMI course (admission, and 6, 12, 18, 24, 36, and 48 hours after, T0-T6, respectively) and correlation with traditional cardiovascular (CV) risk factors (age, gender, hypertension, diabetes mellitus, dyslipidemia, smoking habit) were also assessed. RESULTS: Over time, ROM progressively increased while OXY and NOx decreased. Kinetics of LOX-1 during AMI shows that this biomarker boosts early during the acute event (T1 and T2) and then progressively decreases, being significantly lower from T0 to T6. Different OS-related biomarkers were differentially associated with CV risk factors and CAD or ACS presence. CONCLUSION: Differences in OS-related biomarkers (between groups, according to the response over time during AMI, and to the presence of CV risk factors) confirmed OS involvement in the transition from healthy status to stable CAD and ACS, although evidencing the heterogeneous nature of redox processes. In future, a multi-marker panel including different biomarkers and pathways of oxidative stress could be evaluated as an additive tool to be used in the CV prevention, diagnosis, patient stratification, and treatment.