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 ± 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. © 2018 Elsevier Lt

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. © 2021 Elsevier Lt

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. © 2018 Bentham Science Publishers

Peripheral blood lymphocytes from patients with bipolar disorder demonstrate apoptosis and differential regulation of advanced glycation end products and s100b

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 downstream apoptosis in peripheral lymphocytes of BD patients that may underlie disease etiopathogenesis

Let-7, Mir-98 and Mir-181 as biomarkers for cancer and schizophrenia

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. © 2015 Rizos et al

Cytoprotective mechanisms of dj‐1: Implications in cardiac pathophysiology

DJ‐1 was originally identified as an oncogene product while mutations of the gene encod-ing 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. © 2021 by the authors. Licensee MDPI, Basel, Switzerland