Ameliorative effects of hydrogen sulfide (NaHS) on chronic kidney disease-induced brain dysfunction in rats: implication on role of nitric oxide (NO) signaling.

Chronic kidney disease (CKD) is a major public health problem worldwide and is associated with spatial learning deficits. The aim of the present study was to evaluate the protective effects of hydrogen sulfide (H2S) on CKD-mediated behavioral deficits with emphasis to the role of nitric oxide (NO) in these effects. Fifty rats were randomly allocated to five experimental groups including: sham, Five-sixth (5/6) nephrectomy (Nx), 5/6Nx + NaHS, 5/6Nx + NaHS+L-nitroarginine methyl ester (L-NAME), and 5/6Nx + NaHS+aminoguanidine (AMG). Twelve weeks after 5/6Nx, we evaluated proteinuria, creatinine clearance (CrCl), oxidative/antioxidant status, and hippocampus neuro-inflammation and NO synthase genes in all groups. Furthermore, training trials of all animals were conducted in the Morris water maze (MWM) task one day before animal euthanizing. As predicted, 5/6Nx induced several injuries, including enhancement of proteinuria and reduction of CCr, oxidant/antioxidant imbalance and up-regulation of TNF-α and IL-1ß gene expressions in the hippocampus tissues. As predicted, 5/6Nx resulted in learning and memory impairments, and increased escape latency during acquisition trials in the MWM task. Interestingly, NaHS (H2S donor) improved behavioral deficits, renal dysfunction, accelerated anti-oxidant/anti-inflammatory responses and increased eNOS and decreased iNOS. Moreover, these effects of NaHS were prevented by L-NAME but not AMG co-administration. In conclusion, H2S ameliorates CKD-mediated brain dysfunctions, through interaction with NO signaling in the hippocampus.

Opioid Use Disorder Induces Oxidative Stress and Inflammation: The Attenuating Effect of Methadone Maintenance Treatment.

Objective: Frequent use of opioids produces reactive oxygen species, upregulates inflammatory factors, and contributes to opiate dependence. In this study, we examined perturbations of plasma oxidative and inflammatory markers in patients with opioid use disorder in two phases. In the first phase, we compared the oxidative status in patients with opioid use disorders and in healthy controls; and in the second phase, we examined oxidative changes before and after methadone maintenance treatment. Method: To explore whether oxidative changes were associated with opioid use disorder, we compared plasma oxidative and inflammatory markers in patients with opioid use disorder and in smoking and non-smoking healthy participants. All participants completed measures of catalase (CAT), glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), matrix metalloproteinase (MMP-9), and TNF-α at baseline. Baseline measures were compared using Kruskal-Wallis test. In the second phase, to explore oxidative changes during transition from opium use to methadone, blood and urine samples of patients with opioid use disorder were re-evaluated on Days 3, 7, and 14 after methadone therapy. Repeated measures analysis was used to determine the relative contribution of intervention to changes in CAT, GSH, MDA, SOD, MMP-9, and TNF-α level over time. Results: We observed lower SOD and catalase activities, and higher TNF-α and MMP-9 level in patients compared to the two comparison groups. Opioids exacerbated the oxidative imbalance and superimposed the underlying oxidative injury in smoker comparison group. Methadone therapy was associated with lower MMP-9 and TNF-α level, and higher SOD and catalase activities two weeks after therapy; showing an improvement in oxidative profile. Conclusion: This was an investigation indicating an oxidative imbalance before methadone therapy and during early days of transition from opium use to methadone. Being aware of redox status is crucial for determining an appropriate antioxidant therapy in opioid use disorder.

Impact of opioids on oxidative status and related signaling pathways: An integrated view.

BACKGROUND: Opioids produce reactive oxygen species (ROS) which are highly reactive molecules that damage cells and tissues, and are suggested to contribute to the opioid use disorders. Thus, antioxidant supplementation might improve the disturbance in redox (oxidation-reduction) homeostasis. However, randomized trials on antioxidant therapy have not shown beneficial effects. OBJECTIVES: The purpose of this review is to shed lights on the oxidative changes resulting from opioid use and to highlight the unanswered questions regarding oxidative profile in an effort to provide a comprehensive view of different aspects of an efficient antioxidant therapy in clinical settings. METHODS: The studies were identified and gathered from the PubMed database over the past 16 years (2000-2016). Our search results were limited to articles in English, both animals and human and in vitro and in vivo studies. A total of 50 full text articles were reviewed and summarized. RESULTS: Opioids elevate the level of ROS and decrease the function of enzymatic antioxidants such as superoxide dismutase, catalase, and glutathione peroxidase. They increase the risk of vitamin deficiency and modify gene expression of target cells through ROS production. The effects of opioids on their target cells are exerted through different way and various mechanisms. CONCLUSION: Opioids modulate the redox homeostasis; therefore, understanding the profile of oxidative changes in individuals with opioid use disorder could be of significant benefits in the clinical setting, to help with selection of an efficient antioxidant therapy and diminishing oxidative damage.

Regulatory network analysis of Epstein-Barr virus identifies functional modules and hub genes involved in infectious mononucleosis.

Epstein-Barr virus (EBV) is the most common cause of infectious mononucleosis (IM) and establishes lifetime infection associated with a variety of cancers and autoimmune diseases. The aim of this study was to develop an integrative gene regulatory network (GRN) approach and overlying gene expression data to identify the representative subnetworks for IM and EBV latent infection (LI). After identifying differentially expressed genes (DEGs) in both IM and LI gene expression profiles, functional annotations were applied using gene ontology (GO) and BiNGO tools, and construction of GRNs, topological analysis and identification of modules were carried out using several plugins of Cytoscape. In parallel, a human-EBV GRN was generated using the Hu-Vir database for further analyses. Our analysis revealed that the majority of DEGs in both IM and LI were involved in cell-cycle and DNA repair processes. However, these genes showed a significant negative correlation in the IM and LI states. Furthermore, cyclin-dependent kinase 2 (CDK2) - a hub gene with the highest centrality score - appeared to be the key player in cell cycle regulation in IM disease. The most significant functional modules in the IM and LI states were involved in the regulation of the cell cycle and apoptosis, respectively. Human-EBV network analysis revealed several direct targets of EBV proteins during IM disease. Our study provides an important first report on the response to IM/LI EBV infection in humans. An important aspect of our data was the upregulation of genes associated with cell cycle progression and proliferation.