Emergent Inflammatory Markers and Echocardiographic Indices in Patients with Bronchial Asthma.

Asthma is a heterogeneous disease, characterized by chronic inflammation and oxidative stress of the airways. Several inflammatory pathways including activation of the receptor for advanced glycation end products (RAGE) have been described in the course of the disease. DJ-1 is a redox-sensitive protein with multifaceted roles in mast cell homeostasis and an emerging role in the pathogenesis of asthma. Moreover, cardiac function abnormalities have been described via echocardiography in patients with asthma. The main aim of this study was to investigate the plasma levels of RAGE, its ligands and DJ-1 in asthmatic patients pre- and post-treatment along with echocardiographic indices of cardiovascular function. The study population was divided into two groups. Group A included 13 patients with newly diagnosed bronchial asthma who were free of treatment for at least two weeks and Group B included 12 patients without asthma. An echocardiography examination was performed on all patients. The plasma levels of RAGE, its ligands (AGEs, S100A12, S100B, S100A8/A9), the interleukins (IL-6, IL-1ß) and DJ-1 were measured. No differences were noted among the two groups for baseline characteristics and echocardiographic indices of cardiac function. In Group A, 31% suffered from mild asthma, 54% from moderate asthma and 15% from severe asthma. Plasma levels of IL-6, AGEs and AGE/RAGE ratio were increased and those of S100A12 and DJ-1 were decreased in asthmatics. Pharmacotherapy with corticosteroids/ß2-agonists decreased IL-6, and AGEs, and increased DJ-1. In search of novel approaches in diagnosing and treating patients with asthma, S100A12, ratio AGE/sRAGE, and DJ-1 in addition to IL-6 may prove to be useful tools.

DJ-1 Deficiency Protects against Sepsis-Induced Myocardial Depression.

Oxidative stress is considered one of the early underlying contributors of sepsis-induced myocardial depression. DJ-1, also known as PARK7, has a well-established role as an antioxidant. We have previously shown, in a clinically relevant model of polymicrobial sepsis, DJ-1 deficiency improved survival and bacterial clearance by decreasing ROS production. In the present study, we investigated the role of DJ-1 in sepsis-induced myocardial depression. Here we compared wildtype (WT) with DJ-1 deficient mice at 24 and 48 h after cecal ligation and puncture (CLP). In WT mice, DJ-1 was increased in the myocardium post-CLP. DJ-1 deficient mice, despite enhanced inflammatory and oxidative responses, had an attenuated hypertrophic phenotype, less apoptosis, improved mitochondrial function, and autophagy, that was associated with preservation of myocardial function and improved survival compared to WT mice post-CLP. Collectively, these results identify DJ-1 as a regulator of myocardial function and as such, makes it an attractive therapeutic target in the treatment of early sepsis-induced myocardial depression.

Emerging markers of inflammation and oxidative stress as potential predictors of coronary artery disease.

BACKGROUND AND AIMS: The multi-ligand receptor for advanced glycation end products (RAGE) and its ligands AGEs and S100/calgranulin proteins are important mediators of inflammation and oxidative stress whereas the soluble form of RAGE (sRAGE) by acting as a decoy and the antioxidant PARK7/DJ-1 exert antiatherogenic effects. We examined whether sRAGE and its ligands AGEs, S100A8/A9, S100B, S100A12 and DJ-1 are associated with the presence of angiographic coronary artery disease (CAD) in asymptomatic patients with and without diabetes. METHODS AND RESULTS: Plasma levels of RAGE ligands, sRAGE and DJ-1 were determined in 50 patients with angiographically proven CAD and in 50 age-matched healthy controls. In the whole cohort, lower levels of sRAGE and higher levels of interleukin-6 (IL-6), the RAGE ligands S100B, S100A12 and the AGEs/sRAGE ratio were associated with CAD. In patients without diabetes (n = 72), lower levels of sRAGE and DJ-1 and higher levels of IL-6 and AGEs/sRAGE ratio were associated with CAD. In multivariable analysis, AGEs/sRAGE ratio was an independent predictor of CAD both in the whole cohort (p = 0.034, OR = 1.247, [95%CI: 1.024, 1.0519]) and in the subgroup of patients without diabetes (p = 0.021, OR = 1.363, 95%CI [1.048, 1.771]) on top of established cardiovascular risk factors. CONCLUSION: Alterations in plasma RAGE axis inflammatory mediators are associated with atherosclerosis, and higher levels of AGEs/sRAGE ratio are independently associated with CAD in asymptomatic patients and may act as a novel biomarker for predicting CAD. DJ-1 emerges as promising marker of oxidative stress in CAD patients without diabetes, a finding that deserves further study.

Differential Expression of Circulating Damage-Associated Molecular Patterns in Patients with Coronary Artery Ectasia.

Coronary artery ectasia (CAE) is defined as abnormal dilation of a coronary artery with a diameter exceeding that of adjacent normal arterial segment by >1.5 times. CAE is a pathological entity of the coronary arteries and characterized as a variant of coronary atherosclerosis. CAE frequently coexists with coronary artery disease (CAD). While inflammation appears to be involved, the pathophysiology of CAE remains unclear. Damage-associated molecular patterns (DAMPs), defined as endogenous molecules released from stressed or damaged tissue, are deemed as alarm signals by the innate immune system. Inflammatory agents can generate DAMPs and DAMPs can create a pro-inflammatory state. In a prospective cross-sectional study, we enrolled 29 patients with CAE and non-obstructive CAD, 19 patients with obstructive CAD without CAE, and 14 control subjects with normal (control) coronary arteries age- and sex-matched with the CAE patients, to investigate the differential expression of plasma DAMPs. Patients with CAE and non-obstructive CAD had increased plasma levels of the DAMPs S100B, S100A12, HMGB1, and HSP70, the DAMPs receptor TLR4, and miR328a-3p compared to CAD and controls. Plasma levels of the mir328a-3p target the protective soluble form of the DAMPs receptor for advanced glycation end products (sRAGE), and the antioxidant DJ-1 was decreased in both CAE and CAD compared to controls. In an in vitro human umbilical vein endothelial cells model, circulating levels of S100B, HMGB1, HSP70 as well as CAE patient plasma induced inflammatory responses. The differential expression of the DAMPs S100B, HSP70, HMGB1, and their receptors TLR4 and sRAGE in CAE versus CAD makes them attractive novel biomarkers as therapeutic targets and therapeutics.

DJ-1 binds to Rubicon to Impair LC-3 Associated Phagocytosis.

The ability to effectively clear infection is fundamental to host survival. Sepsis, defined as dysregulated host response to infection, is a heterogenous clinical syndrome that does not uniformly clear intact bacterial or sterile infection (i.e., lipopolysaccharide). These findings were further associated with increased survival in DJ-1 deficient animals exposed to intact bacteria relative to DJ-1 deficient challenged with lipopolysaccharide. We analyzed bacterial and lipopolysaccharide clearance in bone marrow macrophages (BMM) cultured ex vivo from wild-type and DJ-1 deficient mice. Importantly, we demonstrated that DJ-1 deficiency in BMM promotes Rubicon-dependent increase in L3C-associated phagocytosis, non-canonical autophagy pathway used for xenophagy, during bacterial but not lipopolysaccharide infection. In contrast to DJ-1 deficient BMM challenged with lipopolysaccharide, DJ-1 deficient BMM exposed to intact bacteria showed enhanced Rubicon complexing with Beclin-1 and UVRAG and consistently facilitated the assembly of complete autophagolysosomes that were decorated with LC3 molecules. Our data shows DJ-1 impairs or/and delays bacterial clearance and late autophagolysosome formation by binding to Rubicon resulting in Rubicon degradation, decreased L3C-associated phagocytosis, and decreased bacterial clearance in vitro and in vivo - implicating Rubicon and DJ-1 as critical regulators of bacterial clearance in experimental sepsis.

A longitudinal study of alterations of circulating DJ-1 and miR203a-3p in association to olanzapine medication in a sample of first episode patients with schizophrenia.

Among different proposed pathophysiological mechanisms, redox imbalance has been suggested to be a potential contributor in the pathogenesis of schizophrenia. DJ-1 is a redox-sensitive protein that has been shown to have neuroprotective function in the brain in Parkinson's disease and other neurodegenerative diseases. However, a role for DJ-1 in schizophrenia is unknown. Bioinformatic analysis suggested that microRNA (miR)-203a-3p could target the 3' untranslated region (UTR) of DJ-1. In whole blood and blood-derived exosomes of 11 first episode antipsychotic naïve schizophrenia patients, DJ-1 protein and mRNA demonstrated decreased DJ-1 mRNA and protein and increased miR203a-3p levels compared to healthy controls. In whole blood, antipsychotic monotherapy with olanzapine for 6 weeks increased DJ-1 and attenuated miR203a-3p levels, whereas in blood derived exosomes, olanzapine returned DJ-1 and miR203a-3p to levels seen healthy controls. Consistent with this finding, we showed that human umbilical vein endothelial cells (HUVACs) transfected with a DJ-1-3' UTR luciferase reporter construct displayed reduced gene expression when subjected to the oxidative stressor H2O2. Transfection of a miR203a-3p mimic into HUVACs reduced DJ-1-3 'UTR reporter gene expression, while transfection of an anti miR-203a-3p prevented the H2O2-induced downregulation of the reporter gene. We conclude that miR-203a-3p is an essential mediator of oxidative stress in schizophrenia via its ability to target the 3' UTR of DJ-1 and antipsychotic monotherapy restores DJ-1 antioxidant levels by regulating miR203a-3p expression. miR-203a-3p and DJ-1 might represent attractive targets for the treatment of pathologies such as schizophrenia that has underlying oxidative stress.

Differential Regulation of Circulating Soluble Receptor for Advanced Glycation End Products (sRAGEs) and Its Ligands S100A8/A9 Four Weeks Post an Exercise Intervention in a Cohort of Young Army Recruits.

Apart from its beneficial effects on cardiovascular risk factors, an anti-inflammatory effect of exercise is strongly implicated. Yet, data regarding the effect of an exercise intervention on healthy individuals are limited and contradictory. The present study aimed to investigate the effects of a physical activity intervention on the soluble form of the receptor for advanced glycation end products (sRAGEs) and its ligands S100A8/A9. A total of 332 young army recruits volunteered and 169 completed the study. The participants underwent the standard basic training of Greek army recruits. IL-6, IL-1ß, S100A8/A9, and sRAGEs were measured at the beginning and at the end of the training period. Primary rodent adult aortic smooth muscle cells (ASMCs) were analyzed for responsiveness to direct stimulation with S100A8/A9 alone or in combination with sRAGEs. At the end of the training period, we observed a statistically significant reduction in S100A8/A9 (630.98 vs. 472.12 ng/mL, p = 0.001), IL-1ß (9.39 [3.8, 44.14] vs. 5.03 [2.44, 27.3] vs. pg/mL, p = 0.001), and sRAGEs (398.38 vs. 220.1 pg/mL, p = 0.001). IL-6 values did not change significantly after exercise. S100A8/A9 reduction was positively correlated with body weight (r = 0.236 [0.095, 0.370], p = 0.002) and BMI (r = 0.221 [0.092, 0.346], p = 0.004). Direct stimulation of ASMCs with S100A8/A9 increased the expression of IL-6, IL-1ß, and TNF-α and, in the presence of sRAGEs, demonstrated a dose-dependent inhibition. A 4-week military training resulted in significant reduction in the pro-inflammatory cytokines IL-1ß and S100A8/A9 complex. The observed reduction in sRAGEs may possibly reflect diminished RAGE axis activation. Altogether, our findings support the anti-inflammatory properties of physical activity.

Cytoprotective Mechanisms of DJ-1: Implications in Cardiac Pathophysiology.

DJ-1 was originally identified as an oncogene product while mutations of the gene encoding DJ-1/PARK7 were later associated with a recessive form of Parkinson's disease. Its ubiquitous expression and diversity of function suggest that DJ-1 is also involved in mechanisms outside the central nervous system. In the last decade, the contribution of DJ-1 to the protection from ischemia-reperfusion injury has been recognized and its involvement in the pathophysiology of cardiovascular disease is attracting increasing attention. This review describes the current and gaps in our knowledge of DJ-1, focusing on its role in regulating cardiovascular function. In parallel, we present original data showing an association between increased DJ-1 expression and antiapoptotic and anti-inflammatory markers following cardiac and vascular surgical procedures. Future studies should address DJ-1's role as a plausible novel therapeutic target for cardiovascular disease.

Mesenchymal Stem/Stromal Cells Increase Cardiac miR-187-3p Expression in a Polymicrobial Animal Model of Sepsis.

ABSTRACT: Sepsis-induced myocardial dysfunction (MD) is an important pathophysiological feature of multiorgan failure caused by a dysregulated host response to infection. Patients with MD continue to be managed in intensive care units with limited understanding of the molecular mechanisms controlling disease pathogenesis. Emerging evidences support the use of mesenchymal stem/stromal cell (MSC) therapy for treating critically ill septic patients. Combining this with the known role that microRNAs (miRNAs) play in reversing sepsis-induced myocardial-dysfunction, this study sought to investigate how MSC administration alters miRNA expression in the heart. Mice were randomized to experimental polymicrobial sepsis induced by cecal ligation and puncture (CLP) or sham surgery, treated with either MSCs (2.5 × 105) or placebo (saline). Twenty-eight hours post-intervention, RNA was collected from whole hearts for transcriptomic and microRNA profiling. The top microRNAs differentially regulated in hearts by CLP and MSC administration were used to generate a putative mRNA-miRNA interaction network. Key genes, termed hub genes, within the network were then identified and further validated in vivo. Network analysis and RT-qPCR revealed that septic hearts treated with MSCs resulted in upregulation of five miRNAs, including miR-187, and decrease in three top hit putative hub genes (Itpkc, Lrrc59, and Tbl1xr1). Functionally, MSC administration decreased inflammatory and apoptotic pathways, while increasing cardiac-specific structural and functional, gene expression. Taken together, our data suggest that MSC administration regulates host-derived miRNAs production to protect cardiomyocytes from sepsis-induced MD.

Toll-Like Receptors, Associated Biochemical Signaling Networks, and S100 Ligands.

ABSTRACT: Host cells recognize molecules that signal danger using pattern recognition receptors (PRRs). Toll-like receptors (TLRs) are the most studied class of PRRs and detect pathogen-associated molecular patterns and danger-associated molecular patterns. Cellular TLR activation and signal transduction can therefore contain, combat, and clear danger by enabling appropriate gene transcription. Here, we review the expression, regulation, and function of different TLRs, with an emphasis on TLR-4, and how TLR adaptor protein binding directs intracellular signaling resulting in activation or termination of an innate immune response. Finally, we highlight the recent progress of research on the involvement of S100 proteins as ligands for TLR-4 in inflammatory disease.

Heat Shock Protein 70 Is Associated With Cardioversion Outcome and Recurrence of Symptomatic Recent Onset Atrial Fibrillation in Hypertensive Patients.

ABSTRACT: Accumulating evidence indicates that heat shock proteins (HSPs) may represent a suitable biomarker to predict atrial fibrillation (AF). We investigated the relation of circulating serum HSP70 (sHSP70) with inflammatory cytokines and recurrence of symptomatic recent onset AF (ROAF). We enrolled 90 patients with ROAF (the duration from onset of symptoms ≤24 hours) and 30 controls. Patients received amiodarone for cardioversion and rhythm control. The association of serum HSP70, serum interleukin-2 (sIL-2), and serum interleukin-4 (sIL-4) with the presence of cardioversion and AF recurrence within a year was investigated. Toll-like receptor 4 (TLR4) signaling dependence for IL-2 and IL-4 induction in response to stimulation with HSP70 was tested in rat aortic vascular smooth muscle cell cultures. Patients had higher sHSP70 and sIL-2 and lower sIL-4 compared with controls. Serum HSP70 was independently associated with ROAF (P = 0.005) and correlated with sIL-2 (r = 0.494, P < 0.001) and sIL-4 (r = -0.550, P < 0.001). By 48 hours, 71 of the 90 patients were cardioverted, with noncardioverted patients having higher sHSP70 and sIL-2 and lower sIL-4, which were the only independent factors associated with cardioversion. AF recurred in 38 of the 71 cardioverted patients in 1 year. A cutoff value of sHSP70 ≥0.65 ng/mL and sIL-2 ≥0.21 pg/mL was the only independent factor associated with AF recurrence (hazard ratio: 3.311, 95% confidence interval: 1.503-7.293, P = 0.003 and hazard ratio: 3.144, 95% confidence interval: 1.341-7.374, P = 0.008, respectively). The exposure of smooth muscle cell to HSP70 in vitro increased the expression of IL-2 (5×) and IL-4 (1.5×) through TLR4-dependent and receptor-independent mechanisms. In conclusion, sHSP70 and sIL-2 might constitute a prognostic tool for determining the cardioversion and recurrence likelihood in ROAF.

Circulating Ligands of the Receptor for Advanced Glycation End Products and the Soluble Form of the Receptor Modulate Cardiovascular Cell Apoptosis in Diabetes.

We determined whether plasma concentrations of the receptor for advanced glycation end products (RAGE) and the soluble (s) form of RAGE (sRAGE) in healthy individuals and patients with type 2 diabetes (T2D) modulate vascular remodeling. Healthy individuals and patients with T2D were divided into two age groups: young = <35 years old or middle-aged (36-64 years old) and stratified based on normal glucose tolerance (NGT), impaired (IGT), and T2D. Plasma titers of sRAGE, the RAGE ligands, AGEs, S100B, S100A1, S100A6, and the apoptotic marker Fas ligand Fas(L) were measured by enzyme-linked immunosorbent assay (ELISA). The apoptotic potential of the above RAGE ligands and sRAGE were assessed in cultured adult rat aortic smooth muscle cells (ASMC). In NGT individuals, aging increased the circulating levels of AGEs and S100B and decreased sRAGE, S100A1 and S100A6. Middle-aged patients with T2D presented higher levels of circulating S100B, AGEs and FasL, but lower levels of sRAGE, S100A1 and S100A6 than individuals with NGT or IGT. Treatment of ASMC with either AGEs or S100B at concentrations detected in T2D patients increased markers of inflammation and apoptosis. Responses attenuated by concomitant administration of sRAGE. In middle-aged patients with T2D, lower circulating plasma levels of sRAGE may limit decoy and exogenous trapping of deleterious pro-apoptotic/pro-inflammatory RAGE ligands AGEs and S100B, increasing the risk for diabetic complications.

Increased right atrial appendage apoptosis is associated with differential regulation of candidate MicroRNAs 1 and 133A in patients who developed atrial fibrillation after cardiac surgery.

Atrial fibrillation (AF) following on-pump coronary artery bypass grafting (CABG) is a common condition associated with increased morbidity and mortality. We investigated the possibility that miRs may play a contributory role in postoperative AF and associated apoptosis. A total of 42 patients (31 males and 11 females, mean age 65.0 ±â€¯1.3 years) with sinus rhythm and without a history of AF were prospectively enrolled. We examined the levels of the muscle-specific miRs 1 and 133A and markers of apoptosis including TUNEL staining, caspase-3 activation, Bcl2 and Bax mRNAs in right atrial appendage (RAA) biopsies and blood plasma taken before aortic cross-clamping and after reperfusion. After reperfusion, indices of apoptosis increased the RAA. There was no change in tissue or plasma miR -1 and -133A levels compared to pre CABG. However, in patients who postoperatively developed AF (n = 14, 7 males and 7 females), compared to patients that remained in SR (n = 28, 24 males and 4 females) post CABG, tissue miR-1 increased whereas miR-133A decreased and negatively correlated with RAA apoptosis. Mechanistically, overexpression of miR-133A inhibited hypoxia-induced rat neonatal cardiomyocyte apoptosis and phosphorylated pro-survival Akt, responses abolished by a miR-133A antisense inhibitor oligonucleotide or by pre-treatment with an Akt inhibitor. In postoperative AF, differential regulation of pro- and anti-apoptotic miRs-1 and -133A respectively in the RAA, may contribute to postoperative apoptosis. These results provide new insights into molecular mechanisms of postoperative AF with potential therapeutic implications.

A Longitudinal Study of Alterations of S100B, sRAGE and Fas Ligand in Association to Olanzapine Medication in a Sample of First Episode Patients with Schizophrenia.

BACKGROUND & OBJECTIVE: Neuroinflammation has been proposed as a major mechanism in schizophrenic disorder. Specifically, an increase in the inflammatory response in the central nervous system is capable of activating microglial cells, leading to the release of pro-inflammatory cytokines and thus activating apoptotic signaling. An increase in apoptosis may underlie a potential role of immune neuropathology in the etiopathogenesis of schizophrenia and specifically, the onset of the disorder. We analyzed in whole blood, levels of S100B, the receptor for advanced glycation end products (RAGE) and the apoptotic marker Fas Ligand in a sample of 13 first episode of schizophrenia twice at baseline before the initiation of any antipsychotic medication (A) and 6 weeks later following an antipsychotic monotherapy with olanzapine (B) and in a sample of 10 healthy controls. The S100B, RAGE and Fas Ligand showed statistically significant differences before and after treatment; the S100B measurements yielded a p-value of 0.004 while the soluble RAGE and Fas Ligand measurements yielded a p=0.03, and p=0.04 respectively. The differences between cases and controls were not statistically significant for all measurements, with the only exception being the S100B values where both samples A and B showed significantly higher values than the controls with p=8.5x10-8 and p=2.9x10-10 respectively. CONCLUSION: The levels of S100B, RAGE, and Fas Ligand of drug-naive first episode psychosis patients with schizophrenia were significantly higher than that of the same medicated first episode psychosis patients, indicating that an increase of apoptotic signaling is present at the onset of schizophrenia and is also associated with treatment progress.

Antiapoptotic Effect of ß1 Blockers in Ascending Thoracic Aortic Smooth Muscle Cells: The Role of HSP70 Expression.

Heat shock proteins (HSPs) play an important role in the cellular adaptation to stress, a requisite for cell survival. The aortic wall appears to be a target for increased expression of HSPs during surgical stress. We aimed to define the expression and function of aortic HSP70 in 31 patients with normal ascending thoracic aortic diameter who underwent aortic valve replacement due to aortic valve stenosis and in 35 patients with dilated ascending thoracic aorta who underwent replacement of an ascending thoracic aortic aneurysm. To elucidate responsible signaling mechanisms we used an in vitro model of rat hypoxic aortic vascular smooth muscle cell (AVSMC) cultures. We demonstrated an increase in AVSMC HSP70 and an attenuation of the apoptotic markers (TUNEL-positive nuclei, caspase-3 activity, Bax/Bcl2 ratio) in aortic wall tissue specimens from both aortic valve stenosis and ascending thoracic aortic aneurysm patients on ß1 blockade with metoprolol. In vitro, metoprolol treatment of hypoxic rat AVSMCs increased nitric oxide (NO) production, induced heat shock factor 1 transport to the nucleus, upregulated HSP70, decreased p53 phosphorylation and attenuated apoptosis. Blockade of NO production, resulted in decreased HSP70 and prevented the metoprolol-induced anti-apoptotic response of hypoxic AVSMCs. We demonstrate an anti-apoptotic effect of metoprolol dependent on NO-induced HSP70 expression, and thus augmentation of HSP70 expression should be considered as a therapeutic approach to limit apoptosis in the human ascending thoracic aorta of patients undergoing cardiac surgery.

Deficiency of S100B confers resistance to experimental diabetes in mice.

The calcium binding protein S100B has been implicated in diabetic neuronal and vascular complications but has not been examined in the development of diabetes. S100B knock out (S100B KO) and wild-type (WT) mice were injected with 40 mg/kg body weight streptozotocin (STZ) for 5 days. Blood and pancreatic tissue samples were obtained to examine islet structure and function, the profile of glucose and insulin and expression of glucose transporter 2 (Glut2), S100B and its receptor, the receptor for advanced glycation end products (RAGE). Primary islet ß-cells cultures from WT mice were used to test the apoptotic potential of S100B. S100B KO mice were resistant to STZ induced-diabetes with lower urine volume, food and water intake compared to WT mice. S100B increased in the WT islet following diabetes but did not co-localize with beta or peri-islet Schwann cells but with CD3 + T lymphocytes. S100B KO mice exhibited enhanced glucose tolerance, insulin sensitivity, prevented ß-cell destruction and functional impairment in response to STZ treatment. S100B deficiency was associated with decreased Glut2 and RAGE. In primary ß-cell cultures from WT mice, S100B induced reactive oxygen species (ROS) and RAGE-dependent apoptosis. In the STZ diabetic animal model, abrogation of S100B enhances insulin sensitivity and reduces pancreatic islet, and ß-cell destruction. S100B may be a promising target for pharmacological interventions aimed at repressing diabetes.

Cardiac Overexpression of S100A6 Attenuates Cardiomyocyte Apoptosis and Reduces Infarct Size After Myocardial Ischemia-Reperfusion.

BACKGROUND: Cardiomyocyte-specific transgenic mice overexpressing S100A6, a member of the family of EF-hand calcium-binding proteins, develop less cardiac hypertrophy, interstitial fibrosis, and myocyte apoptosis after permanent coronary ligation, findings that support S100A6 as a potential therapeutic target after acute myocardial infarction. Our purpose was to investigate S100A6 gene therapy for acute myocardial ischemia-reperfusion. METHODS AND RESULTS: We first performed in vitro studies to examine the effects of S100A6 overexpression and knockdown in rat neonatal cardiomyocytes. S100A6 overexpression improved calcium transients and protected against apoptosis induced by hypoxia-reoxygenation via enhanced calcineurin activity, whereas knockdown of S100A6 had detrimental effects. For in vivo studies, human S100A6 plasmid or empty plasmid was delivered to the left ventricular myocardium by ultrasound-targeted microbubble destruction in Fischer-344 rats 2 days prior to a 30-minute ligation of the left anterior descending coronary artery followed by reperfusion. Control animals received no therapy. Pretreatment with S100A6 gene therapy yielded a survival advantage compared to empty-plasmid and nontreated controls. S100A6-pretreated animals had reduced infarct size and improved left ventricular systolic function, with less myocyte apoptosis, attenuated cardiac hypertrophy, and less cardiac fibrosis. CONCLUSIONS: S100A6 overexpression by ultrasound-targeted microbubble destruction helps ameliorate myocardial ischemia-reperfusion, resulting in lower mortality and improved left ventricular systolic function post-ischemia-reperfusion via attenuation of apoptosis, reduction in cardiac hypertrophy, and reduced infarct size. Our results indicate that S100A6 is a potential therapeutic target for acute myocardial infarction.

Let-7, mir-98 and mir-183 as biomarkers for cancer and schizophrenia [corrected].

Recent evidence supports a role of microRNAs in cancer and psychiatric disorders such as schizophrenia and bipolar disorder, through their regulatory role on the expression of multiple genes. The rather rare co-morbidity of cancer and schizophrenia is an old hypothesis which needs further research on microRNAs as molecules that might exert their oncosuppressive or oncogenic activity in the context of their role in psychiatric disorders. The expression pattern of a variety of different microRNAs was investigated in patients (N = 6) suffering from schizophrenia termed control, patients with a solid tumor (N = 10) and patients with both schizophrenia and tumor (N = 8). miRNA profiling was performed on whole blood samples using the miRCURY LNA microRNA Array technology (6th & 7th generation). A subset of 3 microRNAs showed a statistically significant differential expression between the control and the study groups. Specifically, significant down-regulation of the let-7p-5p, miR-98-5p and of miR-183-5p in the study groups (tumor alone and tumorand schizophrenia) was observed (p<0.05). The results of the present study showed that let-7, miR-98 and miR-183 may play an important oncosuppressive role through their regulatory impact in gene expression irrespective of the presence of schizophrenia, although a larger sample size is required to validate these results. Nevertheless, further studies are warranted in order to highlight a possible role of these and other micro-RNAs in the molecular pathways of schizophrenia.

Absence of the calcium-binding protein, S100A1, confers pulmonary hypertension in mice associated with endothelial dysfunction and apoptosis.

AIMS: S100A1, a 10-kDa, Ca(2+)-binding protein, is expressed in endothelial cells (ECs) and binds eNOS. Its absence is associated with impaired production of nitric oxide (NO) and mild systemic hypertension. As endothelial dysfunction contributes to clinical and experimental pulmonary hypertension (PH), we investigated the impact of deleting S100A1 in mice, on pulmonary haemodynamics, endothelial function, NO production, associated signalling pathways, and apoptosis. METHODS AND RESULTS: Compared with wild-type (WT), S100A1-knock-out mice (KO) exhibited increased right ventricular (RV) weight/body weight ratio and elevated RV pressure in the absence of altered left ventricular filling pressures, accompanied by increase in wall thickness of muscularized pulmonary arteries and a reduction in microvascular perfusion. In isolated lung preparations, KO revealed reduced basal NO, blunted dose-responsiveness to acetylcholine, and augmented basal and angiotensin (AII)-induced pulmonary vascular resistance (R0) compared with WT. Pre-treatment of KO lungs with S100A1 attenuated the AII-induced increase in pulmonary arterial pressure and R0. S100A1-induced phosphorylation of eNOS, Akt, and ERK1/2 is attenuated in pulmonary EC of KO compared with WT. Basal and TNF-α-induced EC apoptosis is greater in KO vs. WT, and cell survival is enhanced by S100A1 treatment. CONCLUSION: Our data demonstrate that the absence of S100A1 results in PH by disruption of its normal capacity to (i) enhance pulmonary EC function by induction of eNOS activity and NO levels via Akt/ERK1/2 pathways and (ii) promote EC survival. The ability of exogenously administered S100A1 to rescue this phenotype makes it an attractive therapeutic target in the treatment of PH.