Proteomic Analysis of Prehypertensive and Hypertensive Patients: Exploring the Role of the Actin Cytoskeleton.

Hypertension is a pervasive and widespread health condition that poses a significant risk factor for cardiovascular disease, which includes conditions such as heart attack, stroke, and heart failure. Despite its widespread occurrence, the exact cause of hypertension remains unknown, and the mechanisms underlying the progression from prehypertension to hypertension require further investigation. Recent proteomic studies have shown promising results in uncovering potential biomarkers related to disease development. In this study, serum proteomic data collected from Qatar Biobank were analyzed to identify altered protein expression between individuals with normal blood pressure, prehypertension, and hypertension and to elucidate the biological pathways contributing to this disease. The results revealed a cluster of proteins, including the SRC family, CAMK2B, CAMK2D, TEC, GSK3, VAV, and RAC, which were markedly upregulated in patients with hypertension compared to those with prehypertension (fold change ≥ 1.6 or ≤-1.6, area under the curve ≥ 0.8, and q-value < 0.05). Pathway analysis showed that the majority of these proteins play a role in actin cytoskeleton remodeling. Actin cytoskeleton reorganization affects various biological processes that contribute to the maintenance of blood pressure, including vascular tone, endothelial function, cellular signaling, inflammation, fibrosis, and mechanosensing. Therefore, the findings of this study suggest a potential novel role of actin cytoskeleton-related proteins in the progression from prehypertension to hypertension. The present study sheds light on the underlying pathological mechanisms involved in hypertension and could pave the way for new diagnostic and therapeutic approaches for the treatment of this disease.

Epigenetic Regulation of Cancer Stem Cells by the Aryl Hydrocarbon Receptor Pathway.

Compelling evidence has demonstrated that tumor bulk comprises distinctive subset of cells generally referred as cancer stem cells (CSCs) that have been proposed as a strong sustainer and promoter of tumorigenesis and therapeutic resistance. These distinguished properties of CSCs have raised interest in understanding the molecular mechanisms that govern the maintenance of these cells. Numerous experimental and epidemiological studies have demonstrated that exposure to environmental toxins such as the polycyclic aromatic hydrocarbons (PAHs) is strongly involved in cancer initiation and progression. The PAH-induced carcinogenesis is shown to be mediated through the activation of a cytosolic receptor, aryl hydrocarbon receptor (AhR)/Cytochrome P4501A pathway, suggesting a possible direct link between AhR and CSCs. Several recent studies have investigated the role of AhR in CSCs self-renewal and maintenance, however the molecular mechanisms and particularly the epigenetic regulations of CSCs by the AhR/CYP1A pathway have not been reviewed before. In this review, we first summarize the crosstalk between AhR and cancer genetics, with a particular emphasis on the mechanisms relevant to CSCs such as Wnt/ß-catenin, Notch, NF-κB, and PTEN-PI3K/Akt signaling pathways. The second part of this review discusses the recent advances and studies highlighting the epigenetic mechanisms mediated by the AhR/CYP1A pathway that control CSC gene expression, self-renewal, and chemoresistance in various human cancers. Furthermore, the review also sheds light on the importance of targeting the epigenetic pathways as a novel therapeutic approach against CSCs.

Sestrin2 as a Protective Shield against Cardiovascular Disease.

A timely and adequate response to stress is inherently present in each cell and is important for maintaining the proper functioning of the cell in changing intracellular and extracellular environments. Disruptions in the functioning or coordination of defense mechanisms against cellular stress can reduce the tolerance of cells to stress and lead to the development of various pathologies. Aging also reduces the effectiveness of these defense mechanisms and results in the accumulation of cellular lesions leading to senescence or death of the cells. Endothelial cells and cardiomyocytes are particularly exposed to changing environments. Pathologies related to metabolism and dynamics of caloric intake, hemodynamics, and oxygenation, such as diabetes, hypertension, and atherosclerosis, can overwhelm endothelial cells and cardiomyocytes with cellular stress to produce cardiovascular disease. The ability to cope with stress depends on the expression of endogenous stress-inducible molecules. Sestrin2 (SESN2) is an evolutionary conserved stress-inducible cytoprotective protein whose expression is increased in response to and defend against different types of cellular stress. SESN2 fights back the stress by increasing the supply of antioxidants, temporarily holding the stressful anabolic reactions, and increasing autophagy while maintaining the growth factor and insulin signaling. If the stress and the damage are beyond repair, SESN2 can serve as a safety valve to signal apoptosis. The expression of SESN2 decreases with age and its levels are associated with cardiovascular disease and many age-related pathologies. Maintaining sufficient levels or activity of SESN2 can in principle prevent the cardiovascular system from aging and disease.

Influence of the Aryl Hydrocarbon Receptor Activating Environmental Pollutants on Autism Spectrum Disorder.

Autism spectrum disorder (ASD) is an umbrella term that includes many different disorders that affect the development, communication, and behavior of an individual. Prevalence of ASD has risen exponentially in the past couple of decades. ASD has a complex etiology and traditionally recognized risk factors only account for a small percentage of incidence of the disorder. Recent studies have examined factors beyond the conventional risk factors (e.g., environmental pollution). There has been an increase in air pollution since the beginning of industrialization. Most environmental pollutants cause toxicities through activation of several cellular receptors, such as the aryl hydrocarbon receptor (AhR)/cytochrome P450 (CYPs) pathway. There is little research on the involvement of AhR in contributing to ASD. Although a few reviews have discussed and addressed the link between increased prevalence of ASD and exposure to environmental pollutants, the mechanism governing this effect, specifically the role of AhR in ASD development and the molecular mechanisms involved, have not been discussed or reviewed before. This article reviews the state of knowledge regarding the impact of the AhR/CYP pathway modulation upon exposure to environmental pollutants on ASD risk, incidence, and development. It also explores the molecular mechanisms involved, such as epigenesis and polymorphism. In addition, the review explores possible new AhR-mediated mechanisms of several drugs used for treatment of ASD, such as sulforaphane, resveratrol, haloperidol, and metformin.

EGFR Inhibitor Gefitinib Induces Cardiotoxicity through the Modulation of Cardiac PTEN/Akt/FoxO3a Pathway and Reactive Metabolites Formation: In Vivo and in Vitro Rat Studies.

Gefitinib (GEF) is a selective inhibitor of the epidermal growth factor receptor (EGFR) used to treat non-small cell lung cancer. Yet, few cases of cardiotoxicity have been reported. However, the role of the PTEN/Akt/FoxO3a pathway, which mediates GEF anticancer activity, in GEF cardiotoxicity remains unclear. For this purpose, in vitro H9c2 cells and in vivo rat cardiomyocytes were utilized as study models. Treatment of H9c2 cells and Sprague-Dawley rats with GEF significantly induced the expression of hypertrophic and apoptotic markers at mRNA and protein levels with an increased plasma level of troponin. This was accompanied by induction of autophagy and mitochondrial dysfunction in H9c2 cells. Inhibition of cardiac EGFR activity and Akt cellular content of in vitro and in vivo rat cardiomyocytes by GEF increased PTEN and FoxO3a gene expression and cellular content. Importantly, treatment of H9c2 cells with PI3K/Akt inhibitor increased PTEN and FoxO3a mRNA expression associated with potentiation of GEF cardiotoxicity. In addition, by using LC-MS/MS, we showed that GEF is metabolized in the rat heart microsomes into one cyanide- and two methoxylamine-adduct reactive metabolites, where their formation was entirely blocked by CYP1A1 inhibitor, α-naphthoflavone. The current study concludes that GEF induces cardiotoxicity through modulating the expression and function of the cardiac PTEN/AKT/FoxO3a pathway and the formation of CYP1A1-mediated reactive metabolites.

Endoplasmic Reticulum Stress: A Critical Molecular Driver of Endothelial Dysfunction and Cardiovascular Disturbances Associated with Diabetes.

Physical inactivity and sedentary lifestyle contribute to the widespread epidemic of obesity among both adults and children leading to rising cases of diabetes. Cardiovascular disease complications associated with obesity and diabetes are closely linked to insulin resistance and its complex implications on vascular cells particularly endothelial cells. Endoplasmic reticulum (ER) stress is activated following disruption in post-translational protein folding and maturation within the ER in metabolic conditions characterized by heavy demand on protein synthesis, such as obesity and diabetes. ER stress has gained much interest as a key bridging and converging molecular link between insulin resistance, oxidative stress, and endothelial cell dysfunction and, hence, represents an interesting drug target for diabetes and its cardiovascular complications. We reviewed here the role of ER stress in endothelial cell dysfunction, the primary step in the onset of atherosclerosis and cardiovascular disease. We specifically focused on the contribution of oxidative stress, insulin resistance, endothelial cell death, and cellular inflammation caused by ER stress in endothelial cell dysfunction and the process of atherogenesis.

Characterization and assessment of potential microRNAs involved in phosphate-induced aortic calcification.

Medial artery calcification, a hallmark of type 2 diabetes mellitus and chronic kidney disease (CKD), is known as an independent risk factor for cardiovascular mortality and morbidity. Hyperphosphatemia associated with CKD is a strong stimulator of vascular calcification but the molecular mechanisms regulating this process remain not fully understood. We showed that calcification was induced after exposing Sprague-Dawley rat aortic explants to high inorganic phosphate level (Pi , 6 mM) as examined by Alizarin red and Von Kossa staining. This calcification was associated with high Tissue-Nonspecific Alkaline Phosphatase (TNAP) activity, vascular smooth muscle cells de-differentiation, manifested by downregulation of smooth muscle 22 alpha (SM22α) protein expression which was assessed by immunoblot analysis, immunofluorescence, and trans-differentiation into osteo-chondrocyte-like cells revealed by upregulation of Runt related transcription factor 2 (Runx2), TNAP, osteocalcin, and osteopontin mRNA levels which were determined by quantitative real-time PCR. To unravel the possible mechanism(s) involved in this process, microRNA (miR) expression profile, which was assessed using TLDA technique and thereafter confirmed by individual qRT-PCR, revealed differential expression 10 miRs, five at day 3 and 5 at day 6 post Pi treatment versus control untreated aortas. At day 3, miR-200c, -155, 322 were upregulated and miR-708 and 331 were downregulated. After 6 days of treatment, miR-328, -546, -301a were upregulated while miR-409 and miR-542 were downregulated. Our results indicate that high Pi levels trigger aortic calcification and modulation of certain miRs. These observations suggest that mechanisms regulating aortic calcification might involve miRs, which warrant further investigations in future studies.

Water-pipe smoking promotes epithelial-mesenchymal transition and invasion of human breast cancer cells via ERK1/ERK2 pathways.

BACKGROUND: With the increasing popularity of water-pipe smoking (WPS), it is critical to comprehend how WPS may affect women's health. The main goal of this study is to identify the potential outcome of WPS on human breast cancer progression. METHODS: Two breast cancer cell lines, MCF7 and BT20, were used in this investigation. We explored the outcome of WPS on cell morphology and cell invasion using inverted microscope and Biocoat Matrigel invasion chambers. On the other hand, Western blot was employed to study the expression patterns of key control genes of cell adhesion and invasion. RESULTS: Our data reveal that WPS induces epithelial-mesenchymal transition (EMT) of MCF7 and BT20 breast cancer cell lines; thus, WPS enhances cell invasion ability of both cell lines in comparison with their matched controls. More significantly, WPS provokes a down- and up-regulation of E-cadherin and focal adhesion kinase (FAK), respectively, which are important key regulators of cancer progression genes. Finally, our data point out that WPS incites the activation of Erk1/Erk2, which could be behind the stimulation of EMT and invasion as well as the deregulation of E-cadherin and FAK expression. CONCLUSION: Our data show, for the first time, that WPS initiates EMT and stimulates cell invasion of breast cancer cells, which could incite metastatic development in breast cancer patients. Thus, we believe that further studies, both in vitro and in vivo, are required to elucidate the pathogenic outcome of WPS on cancer progression of several human carcinomas including breast.

Myocardial proteases and cardiac remodeling.

Cardiac hypertrophy (CH), characterized by the enlargement of cardiomyocytes, fibrosis and apoptosis, is one of the leading causes of death worldwide. Despite the advances in cardiovascular research, there remains a need to further investigate the signaling pathways that mediate CH in order to identify novel therapeutic targets. One of the hallmarks of CH is the remodeling of the extracellular matrix (ECM). Multiple studies have shown an important role of cysteine proteases and matrix metalloproteinases (MMPs) in the remodeled heart. This review focuses on the role of cysteine cathepins and MMPs in cardiac remodeling.

Emerging importance of chemokine receptor CXCR3 and its ligands in cardiovascular diseases.

The CXC chemokines, CXCL4, -9, -10, -11, CXCL4L1, and the CC chemokine CCL21, activate CXC chemokine receptor 3 (CXCR3), a cell-surface G protein-coupled receptor expressed mainly by Th1 cells, cytotoxic T (Tc) cells and NK cells that have a key role in immunity and inflammation. However, CXCR3 is also expressed by vascular smooth muscle and endothelial cells, and appears to be important in controlling physiological vascular function. In the last decade, evidence from pre-clinical and clinical studies has revealed the participation of CXCR3 and its ligands in multiple cardiovascular diseases (CVDs) of different aetiologies including atherosclerosis, hypertension, cardiac hypertrophy and heart failure, as well as in heart transplant rejection and transplant coronary artery disease (CAD). CXCR3 ligands have also proven to be valid biomarkers for the development of heart failure and left ventricular dysfunction, suggesting an underlining pathophysiological relation between levels of these chemokines and the development of adverse cardiac remodelling. The observation that several of the above-mentioned chemokines exert biological actions independent of CXCR3 provides both opportunities and challenges for developing effective drug strategies. In this review, we provide evidence to support our contention that CXCR3 and its ligands actively participate in the development and progression of CVDs, and may additionally have utility as diagnostic and prognostic biomarkers.

Neuroproteomics and microRNAs studies in multiple sclerosis: transforming research and clinical knowledge in biomarker research.

Multiple sclerosis (MS) is a complex disease characterized by extensive phenotypic variability. Biomarkers to capture the different aspects of MS heterogeneity, and to help make a diagnosis and monitor disease progression, while providing insights into etiopathogenesis and response to treatment, are urgently needed. Omics technologies and research efforts with microRNAs have provide unparalleled opportunities for exploring altered protein profiles associated with molecular mechanisms of disease, substantially expanding the list of candidate biomarkers for MS. This review presents evidence from proteomic studies that have focused on identification of biomarkers released in biofluids as a result of the different pathophysiological processes of MS. Also discussed is the emerging role of miRNAs as complementary biomarkers related to cellular processes occurring in MS patients. Also provided is an overview of candidate biomarkers that have been proposed for elucidating pathophysiological processes and disease activity and for guiding clinical diagnosis and/or therapeutic interventions in MS.

Nanotheragnostic applications for ischemic and hemorrhagic strokes: improved delivery for a better prognosis.

Stroke is the second leading cause of death worldwide and a major cause of long-term severe disability representing a global health burden and one of the highly researched medical conditions. Nanostructured material synthesis and engineering have been recently developed and have been largely integrated into many fields including medicine. Recent studies have shown that nanoparticles might be a valuable tool in stroke. Different types, shapes, and sizes of nanoparticles have been used for molecular/biomarker profiling and imaging to help in early diagnosis and prevention of stroke and for drug/RNA delivery for improved treatment and neuroprotection. However, these promising applications have limitations, including cytotoxicity, which hindered their adoption into clinical use. Future research is warranted to fully develop and effectively and safely translate nanoparticles for stroke diagnosis and treatment into the clinic. This work will discuss the emerging role of nanotheragnostics in stroke diagnosis and treatment applications.

Prevention of RhoA activation and cofilin-mediated actin polymerization mediates the antihypertrophic effect of adenosine receptor agonists in angiotensin II- and endothelin-1-treated cardiomyocytes.

Adenosine receptor activation has been shown to be associated with diminution of cardiac hypertrophy and it has been suggested that endogenously produced adenosine may serve to blunt pro-hypertrophic processes. In the present study, we determined the effects of two pro-hypertrophic stimuli, angiotensin II (Ang II, 100 nM) and endothelin-1 (ET-1, 10 nM) on Ras homolog gene family, member A (RhoA)/Rho-associated, coiled-coil containing protein kinase (ROCK) activation in cultured neonatal rat ventricular myocytes and whether the latter serves as a target for the anti-hypertrophic effect of adenosine receptor activation. Both hypertrophic stimuli potently increased RhoA activity with peak activation occurring 15-30 min following agonist addition. These effects were associated with significantly increased phosphorylation (inactivation) of cofilin, a downstream mediator of RhoA, an increase in actin polymerization, and increased activation and nuclear import of p38 mitogen activated protein kinase. The ability of both Ang II and ET-1 to activate the RhoA pathway was completely prevented by the adenosine A1 receptor agonist N (6)-cyclopentyladenosine, the A2a receptor agonist 2-p-(2-carboxyethyl)-phenethylamino-5'-N-ethylcarboxamidoadenosine, the A3 receptor agonist N (6)-(3-iodobenzyl)adenosine-5'-methyluronamide as well as the nonspecific adenosine analog 2-chloro adenosine. All effects of specific receptor agonists were prevented by their respective receptor antagonists. Moreover, all adenosine agonists prevented either Ang II- or ET-1-induced hypertrophy, a property shared by the RhoA inhibitor Clostridium botulinum C3 exoenzyme, the ROCK inhibitor Y-27632 or the actin depolymerizing agent latrunculin B. Our study therefore demonstrates that both Ang II and ET-1 can activate the RhoA pathway and that prevention of the hypertrophic response to both agonists by adenosine receptor activation is mediated by prevention of RhoA stimulation and actin polymerization.

Metabolomics Profiling of Stages of Coronary Artery Disease Progression.

Coronary artery disease (CAD) and atherosclerosis pose significant global health challenges, with intricate molecular changes influencing disease progression. Hypercholesterolemia (HC), hypertension (HT), and diabetes are key contributors to CAD development. Metabolomics, with its comprehensive analysis of metabolites, offers a unique perspective on cardiovascular diseases. This study leveraged metabolomics profiling to investigate the progression of CAD, focusing on the interplay of hypercholesterolemia, hypertension, and diabetes. We performed a metabolomic analysis on 221 participants from four different groups: (I) healthy individuals, (II) individuals with hypercholesterolemia (HC), (III) individuals with both HC and hypertension (HT) or diabetes, and (IV) patients with self-reported coronary artery disease (CAD). Utilizing data from the Qatar Biobank, we combined clinical information, metabolomic profiling, and statistical analyses to identify key metabolites associated with CAD risk. Our data identified distinct metabolite profiles across the study groups, indicating changes in carbohydrate and lipid metabolism linked to CAD risk. Specifically, levels of mannitol/sorbitol, mannose, glucose, and ribitol increased, while pregnenediol sulfate, oleoylcarnitine, and quinolinate decreased with higher CAD risk. These findings suggest a significant role of sugar, steroid, and fatty acid metabolism in CAD progression and point to the need for further research on the correlation between quinolinate levels and CAD risk, potentially guiding targeted treatments for atherosclerosis. This study provides novel insights into the metabolomic changes associated with CAD progression, emphasizing the potential of metabolites as predictive biomarkers.

Kv7 Channel Activators Flupirtine and ML213 Alleviate Neuropathic Pain Behavior in the Streptozotocin Rat Model of Diabetic Neuropathy.

Background & Objective: Chronic peripheral neuropathic pain (PNP) is a debilitating condition that is associated with many types of injury/diseases, including diabetes mellitus. Patients with longstanding diabetes develop diabetic PNP (DPNP), which is resilient to currently available drugs. The underlying molecular mechanisms of DPNP are still illusive, but Kv7 channels that have been implicated in the pathogenesis of various types of chronic pain are likely to be involved. Indeed, using the streptozotocin (STZ) rat model of DPNP, we have previously shown that Kv7 activation with their non-selective activator retigabine attenuated neuropathic pain behavior suggesting that these channels are implicated in DPNP pathogenesis. Here, we evaluated, in the same STZ model, whether the more potent and more selective Kv7 channel openers flupirtine and ML213 attenuate STZ-induced pain hypersensitivity. Methods: Male Sprague Dawley rats (250-300 g) were used. The STZ model involved a single injection of STZ (60 mg/kg, i.p.). Behavioral testing for mechanical and heat pain sensitivity was performed using a dynamic plantar aesthesiometer and Hargreaves analgesiometer, respectively. Results: STZ rats exhibited behavioral signs of mechanical and heat hypersensitivity as indicated by significant decreases in the mean paw withdrawal threshold (PWT) and mean paw withdrawal latency (PWL), respectively, at 35 days post-STZ treatment. Single injections of flupirtine (10 mg/kg, i.p.) and ML213 (5 mg/kg, i.p.) to STZ rats (35-days after STZ treatment) caused significant increases in the mean PWT, but not PWL, indicating attenuation of mechanical, but not heat hypersensitivity. Both flupirtine and ML213 were as effective as the positive control gabapentin (10/kg, i.p.), and their anti-allodynic effects were prevented by the Kv7 channel-specific blocker XE991 (3 mg/kg, i.p.). Conclusion: The findings suggest that Kv7 channels are involved in the mechanisms of mechanical but not heat hypersensitivity associated with DPNP, and that their activation may prove to be effective in alleviating DPNP symptoms.

Metabolomic profiling reveals key metabolites associated with hypertension progression.

Introduction: Pre-hypertension is a prevalent condition among the adult population worldwide. It is characterized by asymptomatic elevations in blood pressure beyond normal levels but not yet reaching the threshold for hypertension. If left uncontrolled, pre-hypertension can progress to hypertension, thereby increasing the risk of serious complications such as heart disease, stroke, kidney damage, and others. Objective: The precise mechanisms driving the progression of hypertension remain unknown. Thus, identifying the metabolic changes associated with this condition can provide valuable insights into potential markers or pathways implicated in the development of hypertension. Methods: In this study, we utilized untargeted metabolomics profiling, which examines over 1,000 metabolites to identify novel metabolites contributing to the progression from pre-hypertension to hypertension. Data were collected from 323 participants through Qatar Biobank. Results: By comparing metabolic profiles between pre-hypertensive, hypertensive and normotensive individuals, six metabolites including stearidonate, hexadecadienoate, N6-carbamoylthreonyladenosine, 9 and 13-S-hydroxyoctadecadienoic acid (HODE), 2,3-dihydroxy-5-methylthio- 4-pentenoate (DMTPA), and linolenate were found to be associated with increased risk of hypertension, in both discovery and validation cohorts. Moreover, these metabolites showed a significant diagnostic performance with area under curve >0.7. Conclusion: These findings suggest possible biomarkers that can predict the risk of progression from pre-hypertension to hypertension. This will aid in early detection, diagnosis, and management of this disease as well as its associated complications.

Disturbed hemodynamics and oxidative stress interaction in endothelial dysfunction and AAA progression: Focus on Nrf2 pathway.

Hemodynamic shear stress is one of the major factors that are involved in the pathogenesis of many cardiovascular diseases including atherosclerosis and abdominal aortic aneurysm (AAA), through its modulatory effect on the endothelial cell's redox homeostasis and mechanosensitive gene expression. Among important mechanisms, oxidative stress, endoplasmic reticulum stress activation, and the subsequent endothelial dysfunction are attributed to disturbed blood flow and low shear stress in the vascular curvature and bifurcations which are considered atheroprone regions and aneurysm occurrence spots. Many pathways were shown to be involved in AAA progression. Of particular interest from recent findings is, the (Nrf2)/Keap-1 pathway, where Nrf2 is a transcription factor that has antioxidant properties and is strongly associated with several CVDs, yet, the exact mechanism by which Nrf2 alleviates CVDs still to be elucidated. Nrf2 expression is closely affected by shear stress and was shown to participate in AAA. In the current review paper, we discussed the link between disturbed hemodynamics and its effect on Nrf2 as a mechanosensitive gene and its role in the development of endothelial dysfunction which is linked to the progression of AAA.

Cyclophilin A promotes cardiac hypertrophy in apolipoprotein E-deficient mice.

OBJECTIVE: Cyclophilin A (CyPA, encoded by Ppia) is a proinflammatory protein secreted in response to oxidative stress in mice and humans. We recently demonstrated that CyPA increased angiotensin II (Ang II)-induced reactive oxygen species (ROS) production in the aortas of apolipoprotein E (Apoe)-/- mice. In this study, we sought to evaluate the role of CyPA in Ang II-induced cardiac hypertrophy. METHODS AND RESULTS: Cardiac hypertrophy was not significantly different between Ppia+/+ and Ppia-/- mice infused with Ang II (1000 ng/min per kg for 4 weeks). Therefore, we investigated the effect of CyPA under conditions of high ROS and inflammation using the Apoe-/- mice. In contrast to Apoe-/- mice, Apoe-/-Ppia-/- mice exhibited significantly less Ang II-induced cardiac hypertrophy. Bone marrow cell transplantation showed that CyPA in cells intrinsic to the heart plays an important role in the cardiac hypertrophic response. Ang II-induced ROS production, cardiac fibroblast proliferation, and cardiac fibroblast migration were markedly decreased in Apoe-/-Ppia-/- cardiac fibroblasts. Furthermore, CyPA directly induced the hypertrophy of cultured neonatal cardiac myocytes. CONCLUSIONS: CyPA is required for Ang II-mediated cardiac hypertrophy by directly potentiating ROS production, stimulating the proliferation and migration of cardiac fibroblasts, and promoting cardiac myocyte hypertrophy.

The ability of phosphodiesterase-5 inhibitors sildenafil and ordonafil to reverse L-NAME induced cardiac hypertrophy in the rabbit: possible role of calcineurin and p38.

Phosphodiesterase 5 inhibitors (PDE-5Is) can suppress and (or) reverse pressure overload induced myocardial hypertrophy. This study investigated the suppressive effect of 2 PDE-5Is (sildenafil and ordonafil) on N-nitro-l-arginine methyl ester (L-NAME)-induced cardiac hypertrophy in rabbit heart, and examined their possible mechanism of action. L-NAME increased left ventricular thickness to 6.1± 0.18 mm from 4.6 ± 0.13 mm (p < 0.05), which regressed after treatment with either sildenafil or ordonafil to 5.1 ± 0.1 mm and 4.8 ± 0.2 mm, respectively (p < 0.05). Phenylephrine increased neonatal rat ventricular myocyte cell surface area to 131% ± 3% of the control value, which was associated with significant increment in ERK1/2 to 143% ± 5% of the control value (p < 0.05). Ordonafil and sildenafil decreased cell surface area to 95% ± 3% and 90% ± 1% of the control value, respectively. Both drugs decreased ERK1/2 to 88% ± 4% of the control value. Calcineurin activity was significantly decreased after 1 h of treatment with 0.1 mg·L(-1) ordonafil (1.15 ± 0.05, p < 0.05). For sildenafil (0.1 mg·L(-1)), calcineurin activity significantly decreased only after 24 h of incubation (22%). Also p38 activation was attenuated by ordonafil and sildenafil (0.1 mg·L(-1)). It is suggested that both drugs have the ability to reverse L-NAME-induced cardiac hypertrophy and suppress phenylphrine-induced myocyte hypertrophy, and that these effects may be mediated through the attenuation of calcineurin and its downstream signaling pathways (p38) in neonatal rat ventricular myocytes.

Enteric pathogens modulate metabolic homeostasis in the Drosophila melanogaster host.

On quotidian basis, living beings work out an armistice with their microbial flora and a scuffle with invading pathogens to maintain a normal state of health. Although producing virulence factors and escaping the host's immune machinery are the paramount tools used by pathogens in their "arm race" against the host; here, we provide insight into another facet of pathogenic embitterment by presenting evidence of the ability of enteric pathogens to exhibit pathogenicity through modulating metabolic homeostasis in Drosophila melanogaster. We report that Escherichia coli and Shigella sonnei orally infected flies exhibit lipid droplet deprivation from the fat body, irregular accumulation of lipid droplets in the midgut, and significant elevation of systemic glucose and triglyceride levels. Our findings indicate that these detected metabolic alterations in infected flies could be attributed to differential regulation of peptide hormones known to be crucial for lipid metabolism and insulin signaling. Gaining a proper understanding of infection-induced alterations succours in curbing the pathogenesis of enteric diseases and sets the stage for promising therapeutic approaches to quarry infection-induced metabolic disorders.