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Diabetic bladder dysfunction (DBD) comprises a wide spectrum of lower urinary tract symptoms that impact diabetic patients' lives, including urinary frequency, urgency, incontinence, and incomplete bladder emptying. To relieve symptoms, anticholinergics have been widely prescribed and are considered an effective treatment. There is increasing evidence that diabetic patients may benefit from the use of phosphodiesterase 5 (PDE5) inhibitors. This narrative review aims to provide a brief overview of the pathophysiology of DBD along with a focus on cholinergic and phosphodiesterase inhibitors as therapies that benefit DBD. An examination of the literature suggests compelling avenues of research and underscores critical gaps in understanding the mechanisms underlying DBD. New tools and models, especially rodent models, are required to further elucidate the mechanisms of action of current therapies in the treatment of DBS.

Patients with SARS-CoV-2 infection carry an increased risk of cardiovascular disease encompassing various implications, including acute myocardial injury or infarction, myocarditis, heart failure, and arrhythmias. A growing volume of evidence correlates SARS-CoV-2 infection with myocardial injury, exposing patients to higher mortality risk. SARS-CoV-2 attacks the coronary arterial bed with various mechanisms including thrombosis/rupture of preexisting atherosclerotic plaque, de novo coronary thrombosis, endotheliitis, microvascular dysfunction, vasculitis, vasospasm, and ectasia/aneurysm formation. The angiotensin-converting enzyme 2 receptor plays pivotal role on the cardiovascular homeostasis and the unfolding of COVID-19. The activation of immune system, mediated by proinflammatory cytokines along with the dysregulation of the coagulation system, can pose an insult on the coronary artery, which usually manifests as an acute coronary syndrome (ACS). Electrocardiogram, echocardiography, cardiac biomarkers, and coronary angiography are essential tools to set the diagnosis. Revascularization is the first-line treatment in all patients with ACS and obstructed coronary arteries, whereas in type 2 myocardial infarction treatment of hypoxia, anemia and systemic inflammation are indicated. In patients presenting with coronary vasospasm, nitrates and calcium channel blockers are preferred, while treatment of coronary ectasia/aneurysm mandates the use of antiplatelets/anticoagulants, corticosteroids, immunoglobulin, and biologic agents. It is crucial to untangle the exact mechanisms of coronary involvement in COVID-19 in order to ensure timely diagnosis and appropriate treatment. We have reviewed the current literature and provide a detailed overview of the pathophysiology and clinical spectrum associated with coronary implications of SARS-COV-2 infection., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

Acute Respiratory Distress Syndrome (ARDS) is characterized by lung inflammation and increased membrane permeability, which represents the leading cause of mortality in ICUs. Mechanical ventilation strategies are at the forefront of supportive approaches for ARDS. Recently, an increasing understanding of RNA biology, function, and regulation, as well as the success of RNA vaccines, has spurred enthusiasm for the emergence of novel RNA-based therapeutics. The most common types of RNA seen in development are silencing (si)RNAs, antisense oligonucleotide therapy (ASO), and messenger (m)RNAs that collectively account for 80% of the RNA therapeutics pipeline. These three RNA platforms are the most mature, with approved products and demonstrated commercial success. Most recently, miRNAs have emerged as pivotal regulators of gene expression. Their dysregulation in various clinical conditions offers insights into ARDS pathogenesis and offers the innovative possibility of using microRNAs as targeted therapy. This review synthesizes the current state of the literature to contextualize the therapeutic potential of miRNA modulation. It considers the potential for miR-based therapeutics as a nuanced approach that incorporates the complexity of ARDS pathophysiology and the multifaceted nature of miRNA interactions.

Purpose: A variety of pathologic conditions may increase oxidative stress in semen resulting in structural modifications to spermozoa's plasma membrane that interfere with sperm motility, morphology, and count. Antioxidants are currently being marketed to treat male infertility. In semen, antioxidants may decrease oxidative stress and potentially improve sperm parameters. In this narrative, mini-review we evaluated the effectiveness of antioxidants in infertility., Methods: This mini-review of the current literature has been carried out through searching of the PubMed and Google scholar databases., Results and Conclusions: The literature review suggests that there is evidence that oral antioxidants such as selenium, carnitine, zinc, coenzymeQ10, vitamins E and C, etc. alone or in combinations, improve sperm count, motility, morphology as well as pregnancy rates in infertile men with idiopathic oligoasthenospermia. Unfortunately, most of these studies are poorly designed, limited by sample size, varying in dosage, differing in primary end points, and most notably lacking live birth data. Importantly, large randomized, well-designed, placebo-controlled trials are needed., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

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.

Virus-induced lung injury is associated with loss of pulmonary epithelial-endothelial tight junction integrity. While the alveolar-capillary membrane may be an indirect target of injury, viruses may interact directly and/or indirectly with miRs to augment their replication potential and evade the host antiviral defense system. Here, we expose how the influenza virus (H1N1) capitalizes on host-derived interferon-induced, microRNA (miR)-193b-5p to target occludin and compromise antiviral defenses. Lung biopsies from patients infected with H1N1 revealed increased miR-193b-5p levels, marked reduction in occludin protein, and disruption of the alveolar-capillary barrier. In C57BL/6 mice, the expression of miR-193b-5p increased, and occludin decreased, 5-6 days post-infection with influenza (PR8). Inhibition of miR-193b-5p in primary human bronchial, pulmonary microvascular, and nasal epithelial cells enhanced antiviral responses. miR-193b-deficient mice were resistant to PR8. Knockdown of occludin, both in vitro and in vivo, and overexpression of miR-193b-5p reconstituted susceptibility to viral infection. miR-193b-5p inhibitor mitigated loss of occludin, improved viral clearance, reduced lung edema, and augmented survival in infected mice. Our results elucidate how the innate immune system may be exploited by the influenza virus and how strategies that prevent loss of occludin and preserve tight junction function may limit susceptibility to virus-induced lung injury., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

The COVID-19 pandemic has created an urgency to study the host gene response that leads to variable clinical presentations of the disease, particularly the critical illness response. miRNAs have been implicated in the mechanism of host immune dysregulation and thus hold potential as biomarkers and/or therapeutic agents with clinical application. Hence, further analyses of their altered expression in COVID-19 is warranted. An important basis for this is identifying appropriate reference genes for high quality expression analysis studies. In the current report, NanoString technology was used to study the expression of 798 miRNAs in the peripheral blood of 24 critically ill patients, 12 had COVID-19 and 12 were COVID-19 negative. A list of potentially stable candidate reference genes was generated that included ten miRNAs. The top six were analyzed using reverse transcription quantitative polymerase chain reaction (RT-qPCR) in a total of 41 patients so as to apply standard computational algorithms for validating reference genes, namely geNorm, NormFinder, BestKeeper and RefFinder. There was general agreement among all four algorithms in the ranking of four stable miRNAs: miR-186-5p, miR-148b-3p, miR-194-5p and miR-448. A detailed analysis of their output rankings led to the conclusion that miR-186-5p and miR-148b-3p are appropriate reference genes for miRNA expression studies using PaxGene tubes in the peripheral blood of patients critically ill with COVID-19 disease., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Formosa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

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-1β) 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/β2-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.

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., Competing Interests: Declaration of Competing Interest The authors have nothing to disclose., (Copyright © 2023 Elsevier B.V. All rights reserved.)

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.

The ongoing coronavirus disease 2019 (COVID-19) pandemic has had a widespread impact on individuals' mental health through indirect psychological and social mechanisms, related to factors such as fear of infection or death, social isolation, lack of social support and financial instability. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has also been associated with the development or recurrence of neuropsychiatric symptoms, both during the acute phase, as well as during the post-acute 'long-COVID' phase. In addition to the COVID-19 survivors with a mental health history that are at a high risk of experiencing a range of neuropsychiatric symptoms following resolution of acute COVID-19, there is accumulating evidence that a diagnosis of COVID-19 may also be associated with new-onset neuropsychiatric morbidity among survivors without pre-existing mental health disorders. In particular, studies investigating the incidence of post-acute neuropsychiatric sequelae, based mostly on retrospective cohort study designs and data from national health registries, have reported the development of new-onset manifestations, including depression, anxiety, psychotic symptoms, sleep disturbances and fatigue. Nevertheless, when COVID-19 survivors were compared with SARS-CoV-2-negative controls and especially survivors of other disorders (such as influenza), the findings regarding the risk of incident neuropsychiatric manifestations varied among studies. While there is evidence of an association between SARS-CoV-2 infection and the subsequent occurrence of new-onset neuropsychiatric symptoms, especially among patients with increased disease severity, further research using methodological approaches less susceptible to confounding bias is required to establish causal relationships., Competing Interests: DAS is the Editor-in-Chief for the journal, but had no personal involvement in the reviewing process, or any influence in terms of adjudicating the final decision, for this article. The other authors declare that they have no competing interests., (Copyright: © Efstathiou et al.)

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., (© 2022. The Author(s), under exclusive licence to ADMC Associazione Differenziamento e Morte Cellulare.)

There is accumulating evidence in the literature indicating that a number of patients with coronavirus disease 2019 (COVID-19) may experience a range of neuropsychiatric symptoms, persisting or even presenting following the resolution of acute COVID-19. Among the neuropsychiatric manifestations more frequently associated with 'long COVID' are depression, anxiety, post-traumatic stress disorder, sleep disturbances, fatigue and cognitive deficits, that can potentially be debilitating and negatively affect patients' wellbeing, albeit in the majority of cases symptoms tend to improve over time. Despite variations in results obtained from studies using different methodological approaches to define 'long COVID' syndrome, the most widely accepted factors associated with a higher risk of developing neuropsychiatric manifestations include the severity of foregoing COVID-19, the female sex, the presence of comorbidities, a history of mental health disease and an elevation in the levels of inflammatory markers, albeit further research is required to establish causal associations. To date, the pathophysiological mechanisms implicated in neuropsychiatric manifestations of 'long COVID' remain only partially elucidated, while the role of the indirect effects of the COVID-19 pandemic, such as social isolation and uncertainty concerning social, financial and health recovery post-COVID, have also been highlighted. Given the alarming effects of 'long-COVID', interdisciplinary cooperation for the early identification of patients who are at a high risk of persistent neuropsychiatric presentations, beyond COVID-19 recovery, is crucial to ensure that appropriate integrated physical and mental health support is provided, with the aim of mitigating the risks of long-term disability at a societal and individual level., Competing Interests: DAS is the Editor-in-Chief for the journal, but has no personal involvement in the reviewing process, or any influence in terms of adjudicating on the final decision, for this article. The other authors declare that they have no competing interests., (Copyright: © Efstathiou et al.)

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 H 2 O 2. 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 H 2 O 2 -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., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Although mesenchymal stromal (stem) cell (MSC) administration attenuates sepsis-induced lung injury in pre-clinical models, the mechanism(s) of action and host immune system contributions to its therapeutic effects remain elusive. We show that treatment with MSCs decreased expression of host-derived microRNA (miR)-193b-5p and increased expression of its target gene, the tight junctional protein occludin (Ocln), in lungs from septic mice. Mutating the Ocln 3' untranslated region miR-193b-5p binding sequence impaired binding to Ocln mRNA. Inhibition of miR-193b-5p in human primary pulmonary microvascular endothelial cells prevents tumour necrosis factor (TNF)-induced decrease in Ocln gene and protein expression and loss of barrier function. MSC-conditioned media mitigated TNF-induced miR-193b-5p upregulation and Ocln downregulation in vitro When administered in vivo , MSC-conditioned media recapitulated the effects of MSC administration on pulmonary miR-193b-5p and Ocln expression. MiR-193b-deficient mice were resistant to pulmonary inflammation and injury induced by lipopolysaccharide (LPS) instillation. Silencing of Ocln in miR-193b-deficient mice partially recovered the susceptibility to LPS-induced lung injury. In vivo inhibition of miR-193b-5p protected mice from endotoxin-induced lung injury. Finally, the clinical significance of these results was supported by the finding of increased miR-193b-5p expression levels in lung autopsy samples from acute respiratory distress syndrome patients who died with diffuse alveolar damage., Competing Interests: Conflict of interest: C.C. dos Santos has nothing to disclose. Conflict of interest: H. Amatullah has nothing to disclose. Conflict of interest: C.M. Vaswani has nothing to disclose. Conflict of interest: T. Maron-Gutierrez has nothing to disclose. Conflict of interest: M. Kim has nothing to disclose. Conflict of interest: S.H.J. Mei has nothing to disclose. Conflict of interest: K. Szaszi has nothing to disclose. Conflict of interest: A.P.T. Monteiro has nothing to disclose. Conflict of interest: A.K. Varkouhi has nothing to disclose. Conflict of interest: R. Herreroz has nothing to disclose. Conflict of interest: J.A. Lorente has nothing to disclose. Conflict of interest: J.N. Tsoporis has nothing to disclose. Conflict of interest: S. Gupta has nothing to disclose. Conflict of interest: A. Ektesabi has nothing to disclose. Conflict of interest: N. Kavantzas has nothing to disclose. Conflict of interest: V. Salpeas has nothing to disclose. Conflict of interest: J.C. Marshall reports personal fees for data monitoring committee work from AM Pharma, personal fees for advisory board work from Gilead Pharmaceuticals, outside the submitted work. Conflict of interest: P.R.M. Rocco has nothing to disclose. Conflict of interest: P.A. Marsden has nothing to disclose. Conflict of interest: D.J. Weiss has nothing to disclose. Conflict of interest: D.J. Stewart reports other (founding member, equity stake) from Northern Therapeutics, outside the submitted work. Conflict of interest: P. Hu has nothing to disclose. Conflict of interest: W.C. Liles has nothing to disclose., (Copyright ©The authors 2022. For reproduction rights and permissions contact permissions@ersnet.org.)

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-1β, 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-1β (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-1β, 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-1β 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.

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., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 by the Shock Society.)

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., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Shock Society.)

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.

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., Competing Interests: The authors report no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Sepsis is a complicated multi-system disorder characterized by a dysregulated host response to infection. Despite substantial progress in the understanding of mechanisms of sepsis, translation of these advances into clinically effective therapies remains challenging. Mesenchymal Stromal Cells (MSCs) possess immunomodulatory properties that have shown therapeutic promise in preclinical models of sepsis. The therapeutic effects of MSCs may vary depending on the source and type of these cells. In this comparative study, the gene expression pattern and surface markers of bone marrow-derived MSCs (BM-MSCs) and umbilical cord-derived MSCs (UC-MSCs) as well as their therapeutic effects in a clinically relevant mouse model of polymicrobial sepsis, cecal ligation and puncture (CLP), were investigated. The results showed remarkable differences in gene expression profile, surface markers and therapeutic potency in terms of enhancing survival and pro/anti-inflammatory responses between the two MSC types. BM-MSCs improved survival concomitant with an enhanced systemic bacterial clearance and improved inflammatory profile post CLP surgery. Despite some improvement in the inflammatory profile of the septic animals, treatment with UC-MSCs did not enhance survival or bacterial clearance. Overall, the beneficial therapeutic effects of BM-MSCs over UC-MSCs may likely be attributed to their pro-inflammatory function, and to some extent anti-inflammatory features, reflected in their gene expression pattern enhancing macrophage polarization to M1/M2 phenotypes resulting in a balanced pro- and anti-inflammatory response against polymicrobial sepsis., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Oxidative stress is considered one of the early underlying contributors of acute lung injury (ALI) and ventilator-induced lung injury (VILI). DJ-1, also known as PARK7, has a well-established role as an antioxidant. We have previously shown maintaining oxidative balance via the ATF3-Nrf2 axis was important in protection from ALI. Here, we exclusively characterize the role of DJ-1 in sterile LPS-induced ALI and VILI. DJ-1 protein expression was increased after LPS treatment in human epithelial and endothelial cell lines and lungs of wild-type mice. DJ-1 deficient mice exhibited greater susceptibility to LPS-induced acute lung injury as demonstrated by increased cellular infiltration, augmented levels of pulmonary cytokines, enhanced ROS levels and oxidized by-products, increased pulmonary edema and cell death. In a two-hit model of LPS and mechanical ventilation (MV), DJ-1 deficient mice displayed enhanced susceptibility to inflammation and lung injury. Collectively, these results identify DJ-1 as a negative regulator of ROS and inflammation, and suggest its expression protects from sterile lung injury driven by high oxidative stress., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

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.

Critical illnesses including sepsis, acute respiratory distress syndromes, ischemic cardiovascular disorders and acute organ injuries are associated with high mortality, morbidity as well as significant health care system expenses. While these diverse conditions require different specific therapeutic approaches, mesenchymal stem/stromal cell (MSCs) are multipotent cells capable of self-renewal, tri-lineage differentiation with a broad range regenerative and immunomodulatory activities, making them attractive for the treatment of critical illness. The therapeutic effects of MSCs have been extensively investigated in several pre-clinical models of critical illness as well as in phase I and II clinical cell therapy trials with mixed results. Whilst these studies have demonstrated the therapeutic potential for MSC therapy in critical illness, optimization for clinical use is an ongoing challenge. MSCs can be readily genetically modified by application of different techniques and tools leading to overexpress or inhibit genes related to their immunomodulatory or regenerative functions. Here we will review recent approaches designed to enhance the therapeutic potential of MSCs with an emphasis on the technology used to generate genetically modified cells, target genes, target diseases and the implication of genetically modified MSCs in cell therapy for critical illness.

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 ± 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., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

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 β1 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.

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 β-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 β-cell destruction and functional impairment in response to STZ treatment. S100B deficiency was associated with decreased Glut2 and RAGE. In primary β-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 β-cell destruction. S100B may be a promising target for pharmacological interventions aimed at repressing diabetes., (Copyright © 2018 Elsevier Inc. All rights reserved.)

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., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

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., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

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.

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., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

Background: This study addresses the expression of the glycosylated proteins known as advanced glycation end products (AGEs), the calcium binding protein S100B and the apoptotic parameters cytochome c and caspase-3 activity in peripheral lymphocyte cytosolic extracts from a sample of bipolar disorder (BD) patients and healthy (control) subjects., Methods: Cross-sectional study of 35 patients with a clinical diagnosis of bipolar disease (10 euthymic, 12 depressed, 13 manic) and 10 healthy control subjects. Lymphocytes were used as a surrogate model in BD diagnosis and treatment. AGEs and S100B in lymphocyte cell extracts were measured by commercially available enzyme-linked immunosorbent assay., Results: AGEs were lower in all BD patients compared to healthy subjects. Depressed patients had approximately two-fold higher S100B levels compared to healthy subjects. Manic and depressed BD patients had increased superoxide dismutase mRNA levels. Apoptosis as measured by BAX/Bcl2 ratio, cytochrome c release, caspase-3 activity was increased in manic and depressed patients compared to healthy subjects. In the depressed patients, S100B levels correlated with cytochrome c release., Conclusions: In conclusion, our study shows decreased AGEs and increased S100B levels and caspase down-stream apoptosis in peripheral lymphocytes of BD patients that may underlie disease etiopathogenesis.

Members of the S100 protein family have been reported to function as endogenous danger signals (alarmins) playing an active role in tissue inflammation and repair when released from necrotic cells. Here, we investigated the role of S100A1, the S100 isoform with highest abundance in cardiomyocytes, when released from damaged cardiomyocytes during myocardial infarction (MI). Patients with acute MI showed significantly increased S100A1 serum levels. Experimental MI in mice induced comparable S100A1 release. S100A1 internalization was observed in cardiac fibroblasts (CFs) adjacent to damaged cardiomyocytes. In vitro analyses revealed exclusive S100A1 endocytosis by CFs, followed by Toll-like receptor 4 (TLR4)-dependent activation of MAP kinases and NF-κB. CFs exposed to S100A1 assumed an immunomodulatory and anti-fibrotic phenotype characterized i.e. by enhanced intercellular adhesion molecule-1 (ICAM1) and decreased collagen levels. In mice, intracardiac S100A1 injection recapitulated these transcriptional changes. Moreover, antibody-mediated neutralization of S100A1 enlarged infarct size and worsened left ventricular functional performance post-MI. Our study demonstrates alarmin properties for S100A1 from necrotic cardiomyocytes. However, the potentially beneficial role of extracellular S100A1 in MI-related inflammation and repair warrants further investigation., (© 2014 The Authors. Published under the terms of the CC BY 4.0 license.)

We previously showed the emergence of predominantly non-fused murine cells co-expressing cardiac and stromal determinants in co-cultures of murine mesenchymal stromal cells (MSCs) and rat embryonic cardiomyocytes. To determine whether a similar phenotype is detectable in vivo in ischemic myocardium, we infused green fluorescence protein (GFP)-marked MSCs intravenously into wild-type mice in an acute myocardial infarction (AMI) model generated by ischemia/reperfusion (I/R) or fixed coronary artery ligation. We found that infused GFP+ cells were confined strictly to ischemic areas and represented approximately 10% of total cellularity. We showed that over 60% of the cells co-expressed collagen type IV and troponin T or myosin heavy chain, characteristic of MSCs and cardiomyocytes, respectively, and were CD45(-). Nonetheless, up to 25% of the GFP+ donor cells expressed one of two cardiomyocyte markers, either myosin heavy chain or troponin T, in the absence of MSC determinants. We also observed a marked reduction in OCT4 expression in MSCs pre-infusion compared with those lodged in the myocardium, suggesting reduced stem cell properties. Despite the low frequency of lodged donor MSCs, left-ventricular end-diastolic pressure was significantly better in experimental versus saline animals for both AMI (12.10 ± 1.81 vs. 20.50 ± 1.53 mmHg, p < 0.001) and I/R models (8.75 ± 2.95 vs. 17.53 ± 3.85 mmHg, p = 0.004) when measured 21 days after MSC infusion and is consistent with a paracrine effect. Our data indicate that donor MSCs undergo variable degrees of cardiomyocyte reprogramming with the majority co-expressing cardiomyocyte and stromal markers. Further studies are needed to elucidate the factors mediating the extent of cardiomyocyte reprogramming and importance of the cellular changes on tissue repair.

The capacity of imatinib mesylate to reverse established pulmonary arterial hypertension (PAH) has been attributed to a reduction in pulmonary arterial muscularization via inhibition of platelet-derived growth factor receptor-β on vascular smooth muscle cells. However, there is also a significant immunomodulatory component to the action of imatinib that may account for its efficacy in PAH. We found that monocrotaline-induced pulmonary hypertension was associated with a significant decrease in pulmonary natural killer (NK) cells and T lymphocytes and the accumulation of macrophages in the lungs of F344 rats. The prevention of pulmonary hypertension by imatinib blocked these changes in pulmonary leukocyte content and induced elevations in pulmonary interferon-γ, tumor necrosis factor α, and IL-10, corresponding to the enhanced activity of splenic NK cells ex vivo. Treatment with anti-asialo GM1 antiserum (ASGM1), which ablated circulating NK cells and depleted T cells, eliminated the therapeutic benefit of imatinib. ASGM1-treated animals also exhibited significant pulmonary arteriolar muscularization in response to monocrotaline challenge compared with immunocompetent controls despite daily imatinib administration to both groups. In the athymic rat, imatinib decreased right ventricular hypertrophy and pulmonary arteriolar muscularization in monocrotaline-challenged animals versus saline-treated controls but did not prevent pulmonary macrophage accumulation or the development of pulmonary hypertension. These data demonstrate that the immunomodulatory effects of imatinib are critical to its therapeutic action in experimental PAH., (Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Aim: S100B plays a role in cardiac remodeling following myocardial infarction (MI) and in diabetic vascular complications but not examined in diabetic myocardium. We thus examined the effects of targeted deletion of S100B gene on post-MI hearts., Main Methods: Coronary artery ligation or sham was performed 15 weeks after streptozotocin (STZ) or vehicle injection in wild-type (WT) and S100B knock-out (BKO) mice. Left ventricular (LV) structural and functional remodeling was studied 35 days after induction of MI., Key Findings: In diabetes, post-MI remodeling exhibited an attenuated increase in LV mass, dilation, and myocyte hypertrophy in association with increased apoptosis and fibrosis and reduced matrix metalloproteinase-2 (MMP-2) activity. Despite reduced LV dilation, impairment of cardiac function was similar to non-diabetic controls. Both diabetes and MI alone induced myocardial S100B and its canonical receptor for advanced glycation end product (RAGE) expression. By contrast, in post-MI diabetic myocardium, S100B expression was attenuated. Diabetic BKO, following MI demonstrated increased ventricular dilation compared to WT, in association with greater impairment of cardiac function, GLUT4 expression and systemic AGE levels., Significance: These data suggest that S100B expression may serve to modulate cardiac metabolism and adverse consequences of AGE in diabetic post-MI remodeling and function., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Post-infarct remodeling is associated with the upregulation of the receptor for advanced glycation end products (RAGE), the induction of its ligand the calcium binding protein S100B and the release of the potent endothelial-cell specific mitogen vascular endothelial growth factor (VEGF). To determine a possible functional interaction between S100B, RAGE and VEGF we stimulated rat neonatal cardiac myocyte cultures transfected with either RAGE or a dominant-negative cytoplasmic deletion mutant of RAGE with S100B for 48 h. Under baseline conditions, cardiac myocytes express low levels of RAGE and VEGF and secrete VEGF in the medium as measured by ELISA. In RAGE overexpressing myocytes, S100B (100 nM) resulted in increases in VEGF mRNA, VEGF protein, VEGF secretion, and activation of the transcription factor NF-κB. Pre-treatment of RAGE overexpressing myocytes with the NF-κB inhibitor caffeic acid phenethyl ester inhibited increases in VEGF mRNA, VEGF protein and VEGF in the medium by S100B. In myocytes expressing dominant-negative RAGE, S100B did not induce VEGF mRNA, VEGF protein, VEGF secretion or NF-κB activation. In culture, rat neonatal and adult cardiac fibroblasts undergo phenotypic transition to myofibroblasts. Treatment of neonatal and adult myofibroblasts with VEGF (10 ng/mL) induces VEGFR-2 (flk-1/KDR) tyrosine kinase phosphorylation, ERK1/2 phosphorylation and myofibroblast proliferation. Together these data demonstrate that secreted VEGF by cardiac myocytes in response to S100B via RAGE ligation induces myofibroblast proliferation potentially contributing to scar formation observed in infarcted myocardium. This article is part of a Special Issue entitled "Local Signaling in Myocytes"., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

S100B, a calcium-binding protein of the EF-hand type exerts both intracellular and extracellular functions. S100B is induced in the myocardium of human subjects and an experimental rat model following myocardial infarction. Forced expression of S100B in neonatal rat myocyte cultures, and high level expression of S100B in transgenic mice hearts and aortic smooth muscle cells inhibit cardiac hypertrophy and the associated phenotype, arterial smooth muscle proliferation, respectively, but demonstrate increased apoptosis following α(1)-adrenergic stimulation or myocardial infarction. Knocking out S100B, augmented hypertrophy, decreased apoptosis and preserved cardiac function following myocardial infarction. S100B induces apoptosis by an extracellular mechanism by interacting with the receptor for advanced glycation end products and activating ERK1/2 and p53 signaling. The intracellular, and extracellular, roles of S100B are attractive therapeutic targets for the treatment of both cardiac and vascular disease.

Background: Increased nitric oxide production and altered mitochondrial function have been implicated in sepsis-induced cardiac dysfunction. The molecular mechanisms underlying myocardial depression in sepsis and the contribution of nitric oxide in this process however, are incompletely understood., Objectives: To assess the transcriptional profile associated with sepsis-induced myocardial depression in a clinically relevant mouse model, and specifically test the hypothesis that critical transcriptional changes are inducible nitric oxide synthase-dependent., Design: Laboratory investigation., Setting: University affiliated research laboratory., Subjects: C57/BL6 wild type and congenic B6 129P2-Nos2tm1Lau/J (iNOS) mice., Interventions: Assessment of myocardial function after 48 hrs of induction of polymicrobial sepsis by caecal ligation and perforation., Measurements and Results: We compared the myocardial transcriptional profile in C57/BL6 wild type mice and congenic B6 129P2-Nos2tm1Lau/J litter mates after 48 hrs of polymicrobial sepsis induced by caecal ligation and perforation. Profiling of 22,690 expressed sequence tags by gene set enrichment analysis demonstrated that inducible nitric oxide synthase -/- failed to down regulate critical bioenergy and metabolism related genes including the gene for peroxisome proliferator-activated receptor gamma coactivator 1. Bioinformatics analysis identified a striking concordance in down regulation of transcriptional activity of proliferator-activated receptor gamma coactivator 1-related transcription factors resulting in sepsis associated myocardial remodeling as shown by isoform switching in the expression of contractile protein myosin heavy chain. In inducible nitric oxide synthase -/- deficient mice, contractile depression was minimal, and the transcriptional switch was absent., Conclusions: Metabolic and myosin isoform gene expression switch in sepsis-induced myocardial depression is inducible nitric oxide synthase-dependent. Furthermore, we suggest that the molecular switch favoring the expression of fetal isoforms of contraction related proteins is associated with regulation of proliferator-activated receptor gamma coactivator 1 and related transcription factors in an inducible nitric oxide synthase-dependent manner.

Rationale: Post-myocardial infarction ventricular remodeling is associated with the expression of a variety of factors including S100B that can potentially modulate myocyte apoptosis., Objective: This study was undertaken to investigate the expression and function of S100B and its receptor, the receptor for advanced glycation end products (RAGE) in both postinfarction myocardium and in a rat neonatal myocyte culture model., Methods and Results: In a rat model of myocardial infarction following coronary artery ligation, we demonstrate in periinfarct myocytes, upregulation of RAGE, induction of S100B, and release into plasma with consequent myocyte apoptosis. Using a coimmunoprecipitation strategy, we demonstrate a direct interaction between S100B and RAGE. In rat neonatal cardiac myocyte cultures, S100B at concentrations > or = 50 nmol/L induced myocyte apoptosis, as evidenced by increased terminal DNA fragmentation, TUNEL, cytochrome c release from mitochondria to cytoplasm, phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and p53, increased expression and activity of proapoptotic caspase-3, and decreased expression of antiapoptotic Bcl-2. Transfection of a full-length cDNA of RAGE or a dominant-negative mutant of RAGE resulted in increased or attenuated S100B-induced myocyte apoptosis, respectively. Inhibition of ERK1/2 by U0126/PD-98059 or overexpression of a dominant negative p53 comparably inhibited S100B-induced myocyte apoptosis., Conclusions: These results suggest that interaction of RAGE and its ligand S100B after myocardial infarction may play a role in myocyte apoptosis by activating ERK1/2 and p53 signaling. This receptor-mediated mechanism is uniquely amenable to therapeutic intervention.

S100B, a calcium-binding protein of the EF-hand type, exerts both intracellular and extracellular functions. S100B is induced in the myocardium of human subjects and an experimental rat model following myocardial infarction. Forced expression of S100B in neonatal rat myocyte cultures and high level expression of S100B in transgenic mice hearts inhibit cardiac hypertrophy and the associated phenotype but augments myocyte apoptosis following myocardial infarction. By contrast, knocking out S100B, augments hypertrophy, decreases apoptosis and preserves cardiac function following myocardial infarction. Expression of S100B in aortic smooth muscle cells inhibits cell proliferation and the vascular response to adrenergic stimulation. S100B induces apoptosis by an extracellular mechanism via interaction with the receptor for advanced glycation end products and activating ERK1/2 and p53 signaling. The intracellular and extracellular roles of S100B are attractive therapeutic targets for the treatment of both cardiac and vascular diseases.

Objective: To determine if neurally adjusted ventilatory assist (NAVA) that delivers pressure in proportion to diaphragm electrical activity is as protective to acutely injured lungs (ALI) and non-pulmonary organs as volume controlled (VC), low tidal volume (Vt), high positive end-expiratory pressure (PEEP) ventilation., Design: Prospective, randomized, laboratory animal study., Subjects: Twenty-seven male New Zealand white rabbits., Interventions: Anesthetized rabbits with hydrochloric acid-induced ALI were randomized (n = 9 per group) to 5.5 h NAVA (non-paralyzed), VC (paralyzed; Vt 6-ml/kg), or VC (paralyzed; Vt 15-ml/kg). PEEP was adjusted to hemodynamic goals in NAVA and VC6-ml/kg, and was 1 cmH2O in VC15-ml/kg., Measurements and Main Results: PaO2/FiO2; lung wet-to-dry ratio; lung histology; interleukin-8 (IL-8) concentrations in broncho-alveolar-lavage (BAL) fluid, plasma, and non-pulmonary organs; plasminogen activator inhibitor type-1 and tissue factor in BAL fluid and plasma; non-pulmonary organ apoptosis rate; creatinine clearance; echocardiography. PEEP was similar in NAVA and VC6-ml/kg. During NAVA, Vt was lower (3.1 +/- 0.9 ml/kg), whereas PaO2/ FiO2, respiratory rate, and PaCO2 were higher compared to VC6-ml/kg (p<0.05 for all). Variables assessing ventilator-induced lung injury (VILI), IL-8 levels, non-pulmonary organ apoptosis rate, and kidney as well as cardiac performance were similar in NAVA compared to VC6-ml/kg. VILI and non-pulmonary organ dysfunction was attenuated in both groups compared to VC15-ml/kg., Conclusions: In anesthetized rabbits with early experimental ALI, NAVA is as effective as VC6-ml/kg in preventing VILI, in attenuating excessive systemic and remote organ inflammation, and in preserving cardiac and kidney function.

Background: We have previously reported that S100B acts as an intrinsic negative regulator of the myocardial hypertrophic response to norepinephrine (NE)., Methods: To examine the role of S100B in acute and chronic hemodynamic responses to NE stimulation, knockout (KO) mice devoid of the S100B gene, transgenic (TG) mice with forced overexpression of S100B, and control CD1 mice were injected subcutaneously once daily with NE (1.5 mg/kg) or vehicle for 28 days., Results: The acute and chronic hemodynamic responses were not different in CD1 and TG mice. In KO mice, both the chronic and acute increase in blood pressure (BP) in response to NE was attenuated compared with CD1 mice. NE induced ventricular myocyte hypertrophy and smooth muscle proliferation in CD1 mice, responses that were augmented in KO mice. In TG mice, NE did not induce myocyte hypertrophy or smooth muscle cell proliferation. NE treatment of smooth muscle cells derived from KO mice resulted in lower cytosolic calcium concentrations compared to CD1 and TG mice. NE induced S100B in ventricular myocytes and increased S100B in arterial tissues of CD1 and TG mice. The giant phosphoprotein AHNAK is expressed in both ventricular myocytes and aortic smooth muscle cells (ASMCs). In response to NE, S100B co-immunoprecipitates with AHNAK in ventricular myocytes and ASMCs., Conclusion: Thus, absence of S100B is associated with attenuation of the hemodynamic response to catecholamines, in contradistinction to, the augmented cardiac hypertrophy and smooth muscle cell proliferation.

Although bone marrow-derived mesenchymal stromal cells (MSCs) may be beneficial in treating heart disease, their ability to transdifferentiate into functional cardiomyocytes remains unclear. Here, bone marrow-derived MSCs from adult female transgenic mice expressing green fluorescent protein (GFP) under the control of the cardiac-specific alpha-myosin heavy chain promoter were cocultured with male rat embryonic cardiomyocytes (rCMs) for 5-15 days. After 5 days in coculture, 6.3% of MSCs became GFP(+) and stained positively for the sarcomeric proteins troponin I and alpha-actinin. The mRNA expression for selected cardiac-specific genes (atrial natriuretic factor, Nkx2.5, and alpha-cardiac actin) in MSCs peaked after 5 days in coculture and declined thereafter. Despite clear evidence for the expression of cardiac genes, GFP(+) MSCs did not generate action potentials or display ionic currents typical of cardiomyocytes, suggesting retention of a stromal cell phenotype. Detailed immunophenotyping of GFP(+) MSCs demonstrated expression of all antigens used to characterize MSCs, as well as the acquisition of additional markers of cardiomyocytes with the phenotype CD45(-)-CD34(+)-CD73(+)-CD105(+)-CD90(+)-CD44(+)-SDF1(+)-CD134L(+)-collagen type IV(+)-vimentin(+)-troponin T(+)-troponin I(+)-alpha-actinin(+)-connexin 43(+). Although cell fusion between rCMs and MSCs was detectable, the very low frequency (0.7%) could not account for the phenotype of the GFP(+) MSCs. In conclusion, we have identified an MSC population displaying plasticity toward the cardiomyocyte lineage while retaining mesenchymal stromal cell properties, including a nonexcitable electrophysiological phenotype. The demonstration of an MSC population coexpressing cardiac and stromal cell markers may explain conflicting results in the literature and indicates the need to better understand the effects of MSCs on myocardial injury. Disclosure of potential conflicts of interest is found at the end of this article.

S100A6 is induced in myocardium post-infarction in vivo and in response to growth factors and inflammatory cytokines in vitro. Forced expression of S100A6 in cardiomyocytes inhibits regulation of cardiac specific gene expression in response to trophic stimulation. To define regulation and function of S100A6, we characterized the human S100A6 promoter and mapped upstream regulatory elements in rat neonatal cardiac myocytes, fibroblasts, and vascular smooth muscle cells and defined a functional role for S100A6 in tumor necrosis factor-alpha-induced myocyte apoptosis. The functional S100A6 promoter was localized to region -167/+134 containing 167 upstream base pairs. The S100A6 promoter is regulated by positive (-361/-167 and -588/-361) and negative (-1371/-1194) elements. Tumor necrosis factor-alpha induced the maximal S100A6 promoter and transcription factor NF-kappaB (p65 subunit). Electrophoretic mobility shift showed that tumor necrosis factor-alpha induced p65 binding to a potential NF-kappaB-binding site at -460/-451. Chromatin immunoprecipitation analysis revealed p65 is recruited to the S100A6 promoter upon tumor necrosis factor-alpha stimulation. The NF-kappaB inhibitor caffeic acid phenethyl ester and mutation of the NF-kappaB-binding site inhibited S100A6 promoter activation by tumor necrosis factor-alpha. Tumor necrosis factor-alpha induced cardiac myocyte apoptosis. Specific inhibition of S100A6 using a small interfering RNA directed against S100A6 potentiated tumor necrosis factor-alpha-induced myocyte apoptosis, whereas overexpression of S100A6 by gene transfer prevented tumor necrosis factor-alpha-induced myocyte apoptosis by interfering with p53 phosphorylation. These results demonstrate that S100A6 is induced by tumor necrosis factor-alpha via an NF-kappaB-dependent mechanism, serving a role in homeostasis to limit tumor necrosis factor-alpha-induced apoptosis by regulating p53 phosphorylation.

Insulin resistance (IR) and diabetes increase the risk of acute myocardial infarction (MI). Angiotensin receptor blockers (ARBs) have been shown to reduce the risk of cardiovascular events in patients with hypertension and diabetes, and to be beneficial after a large MI. Whether pretreatment with ARBs is beneficial in acute MI is unknown. We evaluated whether pre-, peri-, and post-MI treatment with the ARB losartan improved the outcome in the IR Zucker fatty rat (ZFR). ZFR (n=264) received either losartan (3 mg/kg daily) or vehicle for 7 d prior to MI. Early (24 h) protocol (n=31): ventricular arrhythmias were evaluated post-MI using continuous ambulatory ECG monitoring. Late (38 d) protocol (n=233): losartan was increased to 10 mg/kg daily 10 d post-MI and to 30 mg/kg daily 20 d post-MI. Blood glucose, cardiac hemodynamics and remodeling, GLUT-4, fetal gene expression, and survival were evaluated. In large-MI rats, losartan improved early survival (43% vs. 27% in controls, p=0.01) and late survival (23% vs.15% in controls, p=0.02). Improved early survival was associated with a reduction in ventricular arrhythmias. Losartan reduced pulmonary congestion, cardiac hypertrophy, and fetal gene expression in the absence of statistically significant changes in ventricular dilatation and hemodynamics. Blood glucose and cardiac GLUT-4 expression did not change with losartan. In IR ZFR, losartan improves post-MI survival, likely as a result of an early reduction in ventricular arrhythmias. There was also an associated reduction in pulmonary congestion, hypertrophy, and fetal gene expression.

Angiotensin receptor blockers (ARBs) reduce adverse left ventricular (LV) remodeling and improve LV function and survival when started postmyocardial infarction (MI). ARBs also reduce ventricular arrhythmias during ischemia-reperfusion injury when started pre-MI. No information exists regarding their efficacy and safety when started pre-MI and continued peri- and post-MI. We evaluated whether the ARB losartan improves the outcome when started pre-MI and continued peri- and post-MI. Male Wistar rats (n = 502) were treated for 7 days pre-MI with losartan at a high dose (30 mg.kg(-1).day(-1)), progressively increasing dose (3 mg.kg(-1).day(-1) increased to 10 mg.kg(-1).day(-1) 10 days and 30 mg.kg(-1).day(-1) 20 days post-MI), or no treatment. Ambulatory systolic blood pressure and Holter monitoring were performed for 24 h post-MI. Echocardiography was done 30 days post-MI, and LV remodeling, cardiac hemodynamics, and fetal gene expression were assessed 38 days post-MI. High-dose losartan reduced 24-h post-MI survival compared with the progressive dose and control (21.9% vs. 36.6% and 38.1%, P = 0.033 and P = 0.009, respectively). This was associated with greater hypotension in the high dose and no change in ventricular arrhythmias in all groups. In 24-h post-MI survivors, the progressive dose group had reduced mortality from 24 h to 38 days (8.5% vs. 28.6% for control vs. 38.9% for high dose, P = 0.032 and P = 0.01, respectively). Survivors of both losartan groups demonstrated improved LV remodeling, cardiac hemodynamics, preserved GLUT-4, and reduced cardiac fetal gene expression. Pretreatment with ARBs does not reduce 24-h post-MI ventricular arrhythmias or survival, and high doses increase mortality by causing excessive hypotension. In 24-h post-MI survivors, progressively increasing doses of losartan have multiple beneficial effects, including improved survival.

Background: The vasopeptidase inhibitor omapatrilat improves insulin sensitivity and survival following myocardial infarction (MI). It also improves left ventricular (LV) remodelling following MI and reduces MI size., Objectives: To determine whether improvement in LV remodelling and function is accompanied by a reduction in fetal gene expression of the contractile apparatus, and whether reduction in MI size is accompanied by an increase in the expression of the glucose transporter GLUT-4., Methods: Eighty-nine rats were pretreated for seven days with omapatrilat 20 mg/kg/day and 91 rats were left untreated. MI was induced in 180 Zucker lean male rats by ligating the left anterior descending coronary artery, and omapatrilat was given for another 38 days in the survivors. After 30 days, echocardiography was performed. At 38 days, hemodynamic measurements were performed, the rats were sacrificed and morphological measurements were done. Using quantitative reverse transcriptase-polymerase chain reaction, gene expression was measured in the LV using transcript levels., Results: Treatment with omapatrilat resulted in improved early (24 h) and late (38 days) survival following MI (50% to 67%, P=0.023, and 44% to 59%, P=0.045, respectively). Omapatrilat treatment reduced MI size and resulted in beneficial ventricular remodelling as reflected by a reduction in cardiac dimensions by echocardiography, and LV and right ventricular hypertrophy, which resulted in borderline hemodynamic improvement. A large MI resulted in an increased expression of beta-myosin heavy chain, alpha-skeletal actin and atrial natriuretic peptide, and a decreased expression of GLUT-4. Omapatrilat treatment did not modify the expression of these genes., Conclusions: The results suggest that the vasopeptidase inhibitor omapatrilat does not modify fetal gene expression of the contractile apparatus or the expression of GLUT-4 despite reducing cardiac hypertrophy and MI size.

S100A6 (calcyclin), a member of the S100 family of EF-hand Ca2+ binding proteins, has been implicated in the regulation of cell growth and proliferation. We have previously shown that S100B, another member of the S100 family, is induced postinfarction and limits the hypertrophic response of surviving cardiac myocytes. We presently report that S100A6 expression is also increased in the periinfarct zone of rat heart postinfarction and in cultured neonatal rat myocytes by treatment with several trophic agents, including platelet-derived growth factor (PDGF), the alpha1-adrenergic agonist phenylephrine (PE), and angiotensin II (AII). Cotransfection of S100A6 in cultured neonatal rat cardiac myocytes inhibits induction of the cardiac fetal gene promoters skeletal alpha-actin (skACT) and beta-myosin heavy chain (beta-MHC) by PDGF, PE, AII, and the prostaglandin F2alpha (PGF2alpha), induction of the S100B promoter by PE, and induction of the alpha-MHC promoter by triiodothyronine (T3). By contrast, S100B cotransfection selectively inhibited only PE induction of skACT and beta-MHC promoters. Fluorescence microscopy demonstrated overlapping intracellular distribution of S100B and S100A6 in transfected myocytes and in postinfarct myocardium but heterodimerization of the two proteins could not be detected by co-immunoprecipitation. We conclude that S100A6 may function as a global negative modulator of differentiated cardiac gene expression comparable to its putative role in cell cycle progression of dividing cells.