Distinct pharmacological properties of gaseous CO and CO-releasing molecule in human platelets

Carbon monoxide (CO)-gaseous or released by CO-RMs-both possess antiplatelet properties; however, it remains uncertain whether the mechanisms involved are the same. Here, we characterise the involvement of soluble guanylate cyclase (sGC) in the effects of CO-delivered by gaseous CO-saturated buffer (COG) and generated by CORM-A1-on platelet aggregation and energy metabolism, as well as on vasodilatation in aorta, using light transmission aggregometry, Seahorse XFe technique, and wire myography, respectively. ODQ completely prevented the inhibitory effect of COG on platelet aggregation, but did not modify antiplatelet effect of CORM-A1. In turn, COG did not affect, whereas CORM-A1 substantially inhibited energy metabolism in platelets. Even though activation of sGC by BAY 41-2272 or BAY 58-2667 inhibited significantly platelet aggregation, their effects on energy metabolism in platelets were absent or weak and could not contribute to antiplatelet effects of sGC activation. In contrast, vasodilatation of murine aortic rings, induced either by COG or CORM-A1, was dependent on sGC. We conclude that the source (COG vs. CORM-A1) and kinetics (rapid vs. slow) of CO delivery represent key determinants of the mechanism of antiplatelet action of CO, involving either impairment of energy metabolism or activation of sGG

Renin-Angiotensin-Aldosterone System in Heart Failure: Focus on Nonclassical Angiotensin Pathways as Novel Upstream Targets Regulating Aldosterone

Aldosterone plays an important role in the regulation of blood pressure, body fluid, and electrolyte homeostasis. Overactivation of aldosterone/mineralocorticoid receptor (MR) pathway leads to hypertension, atherosclerosis, vascular damage, heart failure, and chronic kidney disease and is involved in many other diseases associated with endothelial dysfunction, inflammation, fibrosis, and metabolic disorders. Aldosterone is a final product of the renin-angiotensin-aldosterone system (RAAS), and its production is activated by angiotensin II, while angiotensin-(1–7) negatively regulates angiotensin II-mediated aldosterone production and in some experimental models inhibits aldosterone-induced damage in target tissues. In fact, the aldosterone/mineralocorticoid receptor-dependent pathway is regulated upstream by at least two major axes of RAAS: classical axis (ACE/Ang II) and nonclassical axis (ACE2/Ang-(1–7)). The relative balance between these two axes determines aldosterone production and activity. To better understand the regulation of aldosterone activity in physiology and diseases, it is important to analyze the role of aldosterone/mineralocorticoid receptor-dependent pathways in the context of upstream angiotensin pathways as some of the recently described mechanisms of RAAS represent possible novel upstream targets to inhibit aldosterone/mineralocorticoid receptor-dependent responses. In this review, we highlight the complexity of angiotensin pathways focusing on their role in various tissues in heart failure, with particular emphasis on nonclassical pathways including protective ACE2/Ang-(1–7) axis and detrimental Ang-(1–12)/chymase/Ang II axis

Sex-specific differences of adenosine triphosphate levels in red blood cells isolated from ApoE/LDLR double-deficient mice

In this study for the first time, we investigated the correlation between sex-specific differences in adenosine triphosphate (ATP) levels in red blood cells (RBCs) and their mechanical, biochemical, and morphological alterations during the progression of atherosclerosis in ApoE/LDLR double-deficient ($ApoE/LDLR^{-/-}$) mice. Our results indicate that both sex and age affect alterations in RBCs of both $ApoE/LDLR^{-/-}$ and C57BL/6J mice. When compared with male RBCs, female RBCs were characterized by lower basal ATP and mean corpuscular hemoglobin concentration (MCHC), higher hemoglobin concentration (HGB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), deformability, and phosphatidylserine (PS) exposure levels, regardless of age in both, $ApoE/LDLR^{-/-}$ and C57BL/6J mice. $ApoE/LDLR^{-/-}$ mice compared with age-matched controls showed lower basal ATP levels regardless of age and sex. Intracellular ATP level of RBCs was decreased solely in senescent female C57BL/6J mice, while it was elevated in males. Basal extracellular ATP levels were 400 times lower than corresponding intracellular level. In conclusion, basal ATP levels, RBC morphology, deformability, PS exposure levels alterations are sex-dependent in mice. Changes in basal ATP levels were correlated with PS exposure and trends of changes in MCV. Trends of changes of the most RBC parameters were similar in both sexes of $ApoE/LDLR^{-/-}$ mice compared with age-matched controls, however, their kinetics and levels vary greatly between different stages of disease progression

Spectroscopic signature of red blood cells in a D-galactose-induced accelerated aging model

This work presents a semi-quantitative spectroscopic approach, including FTIR-ATR and Raman spectroscopies, for the biochemical analysis of red blood cells (RBCs) supported by the biochemical, morphological and rheological reference techniques. This multi-modal approach provided the description of the RBC alterations at the molecular level in a model of accelerated aging induced by administration of D-galactose (D-gal), in comparison to natural aging. Such an approach allowed to conclude that most age-related biochemical RBC membrane changes (a decrease in lipid unsaturation and the level of phospholipids, or an increase in acyl chain shortening) as well as alterations in the morphological parameters and RBC deformability are well reflected in the D-gal model of accelerated aging. Similarly, as in natural aging, a decrease in LDL level in blood plasma and no changes in the fraction of glucose, creatinine, total cholesterol, HDL, iron, or triglycerides were observed during the course of accelerated aging. Contrary to natural aging, the D-gal model led to an increase in cholesterol esters and the fraction of total esterified lipids in RBC membranes, and evoked significant changes in the secondary structure of the membrane proteins. Moreover, a significant decrease in the phosphorous level of blood plasma was specific for the D-gal model. On the other hand, natural aging induced stronger changes in the secondary structures of the proteins of the RBCs' interior. This work proves that research on the aging mechanism, especially in circulation-related diseases, should employ the D-gal model with caution. Nonetheless, the D-gal model enables to imitate age-related rheological alterations in RBCs, although they are partially derived from different changes observed in the RBC membrane at the molecular level

Vascular cognitive impairment linked to brain endothelium inflammation in early stages of heart failure in mice

Background Although advanced heart failure ( HF ) is a clinically documented risk factor for vascular cognitive impairment, the occurrence and pathomechanisms of vascular cognitive impairment in early stages of HF are equivocal. Here, we characterize vascular cognitive impairment in the early stages of HF development and assess whether cerebral hypoperfusion or prothrombotic conditions are involved. Methods and Results Tgαq*44 mice with slowly developing isolated HF triggered by cardiomyocyte‐specific overexpression of G‐αq*44 protein were studied before the end‐stage HF , at the ages of 3, 6, and 10 months: before left ventricle dysfunction; at the stage of early left ventricle diastolic dysfunction (with preserved ejection fraction); and left ventricle diastolic/systolic dysfunction, respectively. In 6‐ to 10‐month‐old but not in 3‐month‐old Tgαq*44 mice, behavioral and cognitive impairment was identified with compromised blood‐brain barrier permeability, most significantly in brain cortex, that was associated with myelin sheet loss and changes in astrocytes and microglia. Brain endothelial cells displayed increased E‐selectin immunoreactivity, which was accompanied by increased amyloid‐β 1‐42 accumulation in piriform cortex and increased cortical oxidative stress (8‐ OH dG immunoreactivity). Resting cerebral blood flow measured by magnetic resonance imaging in vivo was preserved, but ex vivo NO ‐dependent cortical arteriole flow regulation was impaired. Platelet hyperreactivity was present in 3‐ to 10‐month‐old Tgαq*44 mice, but it was not associated with increased platelet‐dependent thrombogenicity. Conclusions We report for the first time that vascular cognitive impairment is already present in the early stage of HF development, even before left ventricle systolic dysfunction. The underlying pathomechanism, independent of brain hypoperfusion, involves preceding platelet hyperreactivity and brain endothelium inflammatory activation. </jats:sec

Trends in biomedical analysis of red blood cells – Raman spectroscopy against other spectroscopic, microscopic and classical techniques

Application of modern and innovative spectroscopic and microscopic approaches to biomedical analysis opens new horizons and sheds new light on many unexplored scientific territories. In this review, we critically summarize up-to-date Raman-based methodologies for red blood cells (RBCs) analysis used in biology and medicine, and compare them with both classical, as well as other spectroscopic and microscopic approaches. The main emphasis is placed on the advantages, disadvantages and capabilities of each technique for detection of RBC deteriorations and RBC-related diseases. Although currently used classical techniques of medical analysts serve as a gold standard for clinicians in diagnosis of erythropathies, they provide insufficient insight into RBC alterations at the molecular level. In addition, there is a demand for non-destructive and label-free analytical techniques for rapid detection and diagnosis of erythropathies. Their recognition often requires multimodal methodology comprising application of methods including sophisticated spectroscopy-based techniques, where Raman-based approaches play an important role

Temporal relationship between systemic endothelial dysfunction and alterations in erythrocyte function in a murine model of chronic heart failure

Endothelial dysfunction (ED) and red blood cell distribution width (RDW) are both prognostic factors in heart failure (HF), but the relationship between them is not clear. In this study, we used a unique mouse model of chronic HF driven by cardiomyocyte-specific overexpression of activated Gαq protein (Tgαq*44 mice) to characterise the relationship between the development of peripheral ED and the occurrence of structural nanomechanical and biochemical changes in red blood cells (RBCs).Systemic ED was detected in vivo in 8-month-old Tgαq*44 mice, as evidenced by impaired acetylcholine-induced vasodilation in the aorta and increased endothelial permeability in the brachiocephalic artery. ED in the aorta was associated with impaired nitric oxide (NO) production in the aorta and diminished systemic NO bioavailability. ED in the aorta was also characterised by increased superoxide and eicosanoid production. In 4- to 6-month-old Tgαq*44 mice, RBC size and membrane composition displayed alterations that did not result in significant changes in their nanomechanical and functional properties. However, 8-month-old Tgαq*44 mice presented greatly accentuated structural and size changes and increased RBC stiffness. In 12-month-old Tgαq*44 mice, the erythropathy was featured by severely altered RBC shape and elasticity, increased RDW, impaired RBC deformability, and increased oxidative stress (GSH/GSSH ratio). Moreover, RBCs taken from 12-month-old Tgαq*44 mice, but not from 12-month-old FVB mice, co-incubated with aortic rings from FVB mice, induced impaired endothelium-dependent vasodilation and this effect was partially reversed by an arginase inhibitor (ABH, 2(S)-amino-6-boronohexanoic acid).In the Tgαq*44 murine model of HF, systemic endothelial dysfunction accelerates erythropathy and, conversely, erythropathy may contribute to endothelial dysfunction. These results suggest that erythropathy may be regarded as a marker and a mediator of systemic endothelial dysfunction in HF. In particular, targeting RBC arginase may represent a novel treatment strategy for systemic endothelial dysfunction in HF. RBC arginase and possibly other RBC-mediated mechanisms may represent novel therapeutic targets for systemic endothelial dysfunction in HF.Endothelial dysfunction (ED) and red blood cell distribution width (RDW) both have prognostic value for heart failure (HF), but it is not known whether these pathologies are related. We comprehensively characterized endothelial and RBC functional status in a unique murine model of chronic heart failure with a prolonged time course of HF progression. Our results suggest that ED accelerates erythropathy and, conversely, erythropathy may contribute to ED. Accordingly, erythropathy in HF reflects ED and involves various changes (in functional, structural, nanomechanical, and biochemical levels) that could have diagnostic and therapeutic significance for HF

Changes in the level of endocannabinoids after acute and repeated administration of antidepressant medication with simultaneous blockade of CB2 receptors in different rat brain structures

Wstęp: Celem niniejszej pracy była ocena wpływu leków przeciwdepresyjnych tj.: imipramina (IMI), escitalopram (ESC) i tianeptyna (TIA) na poziom anadamidu (AEA) i 2-arachidonyloglicerolu (2-AG) w badanych strukturach mózgowych w warunkach równoczesnej farmakologicznej blokady receptorów kanabinoidowych CB2 za pomocą antagonisty AM630.Metodyka: Badane leki przeciwdepresyjne IMI (15 mg/kg), ESC (10 mg/kg) lub TIA (10 mg/kg) podawano badanym zwierzętom dootrzewnowo- jednorazowo lub chronicznie (14 dni) przy zastosowaniu równoczesnej blokady receptora CB2 przy użyciu AM630 (1 mg/kg). Poziom endokanabinoidów w korze przedczołowej, czołowej, hipokampie, prażkowiu grzbietowym, jądzie półleżącym oraz móżdżku oznaczono za pomocą chromatografii cieczowej sprzężonej ze spektrometrią mas. Wyniki: Wzrost poziomu AEA po podaniu wielokrotnym IMI, ESC oraz TIA został zablokowany i przywrócony do poziomu grupy kontrolnej przy równoczesnej blokadzie receptorów CB2 w hipokampie, natomiast podwyższony poziom AEA utrzymuje się prążkowiu grzbietowym (brak blokady efektu). Wzrost poziomu 2-AG obserwowany po podaniu wielokrotnym IMI i TIA w korze czołowej nie został zablokowany po równoczesnym podaniu antagonisty receptorów CB2, natomiast po chronicznych podaniach ESC spadek stężenia 2-AG został zablokowany. Blokada receptora CB2 blokowała efekty wszystkich leków na poziom 2-AG w móżdżku oraz odwracała spadek poziomu 2-AG wywołany chronicznym podaniem ESC w korze przedczołowej. Wnioski: Wybrane leki przeciwdepresyjne o różnym mechanizmie działania oraz antagonista receptorów CB2 po ostrym i przewlekłym stosowaniu indukują zmiany (wzrosty/spadki) w tkankowych poziomach endokanabinoidów w mózgu szczurów..Background: The aim of this study was to evaluate the effect of antidepressants, i.e.: imipramine (IMI), escitalopram (ESC) and tianeptine (TIA) upon the level of anadamidu (AEA) and 2-arachidonyloglicerolu (2-AG) in the tested structures of the brain. This took place under conditions of simultaneous pharmacological CB2 cannabinoid receptor blockade using antagonist AM630.Methodology: The tested antidepressants IMI (15 mg/kg), ESC (10 mg/ kg) or TIA (10 mg/kg) were administered intraperitoneally to the animals once and chronic (14 days) using simultaneous CB2 receptor blockade with AM630 (1 mg/kg). The level of endocannabinoids in the prefrontal cortex, frontal cortex, hippocampus, dorsal striatum and the cerebellum was marked by liquid chromatography with mass spectrometry.Results: We observed increased levels of AEA after repeated administration of IMI, ESC and TIA. The rise of AEA has been blocked and restored to the level of the control group with simultaneous blockade of CB2 receptors in the hippocampus, while elevated level of AEA was maintained in dorsal striatum (no blocking effect). On the other hand, increased level of 2-AG observed, after repeated administration of IMI and TIA in the frontal cortex. However, we didn’t notice the effect of the blockade after the co-administration of CB2 the antagonist receptor. We observed that after chronic administrations of ESC a decrease level in the concentration of 2-AG, after which this decrease was blocked . AM630 blocked CB2 receptor which provided to the blocking effect of all medicines at the levels of 2-AG in the cerebellum and reversed the decline in 2-AG caused by chronic administration of the ESC in the prefrontal cortex.Conclusions: Different classes of antidepressants and antagonist of the CB2 cannabinoid receptor induce after acute and chronic dosing a change (increase/decrease) in the tissue levels of endocannabinoids in the brain of rats