Adverse childhood experiences and reoccurrence of illness impact the gut microbiome, which affects suicidal behaviours and the phenome of major depression: towards enterotypic phenotypes

The first publication demonstrating that major depressive disorder (MDD) is associated with alterations in the gut microbiota appeared in 2008 (Maes et al., 2008). The purpose of the present study is to delineate a) the microbiome signature of the phenome of depression, including suicidal behaviours (SB) and cognitive deficits; the effects of adverse childhood experiences (ACEs) and recurrence of illness index (ROI) on the microbiome; and the microbiome signature of lowered high-density lipoprotein cholesterol (HDLc). We determined isometric log-ratio abundances or prevalences of gut microbiome phyla, genera, and species by analysing stool samples from 37 healthy Thai controls and 32 MDD patients using 16S rDNA sequencing. Six microbiome taxa accounted for 36% of the variance in the depression phenome, namely Hungatella and Fusicatenibacter (positive associations) and Butyricicoccus, Clostridium, Parabacteroides merdae, and Desulfovibrio piger (inverse association). This profile (labelled enterotype 1) indicates compositional dysbiosis, is strongly predicted by ACE and ROI, and is linked to SB. A second enterotype was developed that predicted a decrease in HDLc and an increase in the atherogenic index of plasma (Bifidobacterium, P. merdae, and Romboutsia were positively associated, while Proteobacteria and Clostridium sensu stricto were negatively associated). Together, enterotypes 1 and 2 explained 40.4% of the variance in the depression phenome, and enterotype 1 in conjunction with HDLc explained 39.9% of the variance in current SB. In conclusion, the microimmuneoxysome is a potential new drug target for the treatment of severe depression and SB and possibly for the prevention of future episodes.

Carfilzomib Mitigates Lipopolysaccharide/D-Galactosamine/Dimethylsulfoxide-Induced Acute Liver Failure in Mice

Acute liver failure (ALF) is a disease accompanied by severe liver inflammation. No effective therapy is available yet apart from liver transplantation; therefore, developing novel treatments for ALF is urgently required. Inflammatory mediators released by NF-кB activation play an essential role in ALF. Proteasome inhibitors have many medical uses, such as reducing inflammation and NF-кB inhibition, which are believed to account for most of their repurposing effects. This study was undertaken to explore the possible protective effects and the underlying mechanisms of carfilzomib, a proteasome inhibitor, in a mouse model of ALF induced by lipopolysaccharide/D-galactosamine/dimethylsulfoxide (LPS/GalN/DMSO). Carfilzomib dose-dependently protected mice from LPS/GalN/DMSO-induced liver injury, as indicated by the decrease in serum alanine aminotransferase and aspartate aminotransferase levels. LPS/GalN/DMSO increased TNF-α, NF-кB, lipid peroxidation, NO, iNOS, cyclooxygenase-II, myeloperoxidase, and caspase-3 levels. Carfilzomib administration mitigated LPS/GalN/DMSO-induced liver damage by decreasing the elevated levels of TNF-α, NF-кB, lipid peroxidation, nitric oxide, iNOS, cyclooxygenase-II, myeloperoxidase, caspase-3, and histopathological changes. A restored glutathione level was also observed in the carfilzomib-treated LPS/GalN/DMSO mice. Our results demonstrate that carfilzomib protects against LPS/GalN/DMSO-induced ALF by inhibiting NF-кB, decreasing inflammatory mediators, oxidative/nitrosative stress, neutrophil recruitment, and apoptosis, suggesting that carfilzomib may be a potential therapeutic agent for ALF.

S-Glutathionylation and S-Nitrosylation as Modulators of Redox-Dependent Processes in Cancer Cell

Development of oxidative/nitrosative stress associated with the activation of oncogenic pathways results from the increase in the generation of reactive oxygen and nitrogen species (ROS/RNS) in tumor cells, where they can have a dual effect. At high concentrations, ROS/RNS cause cell death and limit tumor growth at certain phases of its development, while their low amounts promote oxidative/nitrosative modifications of key redox-dependent residues in regulatory proteins. The reversibility of such modifications as S-glutathionylation and S-nitrosylation that proceed through the electrophilic attack of ROS/RNS on nucleophilic Cys residues ensures the redox-dependent switch in the activity of signaling proteins, as well as the ability of these compounds to control cell proliferation and programmed cell death. The content of S-glutathionylated and S-nitrosylated proteins is controlled by the balance between S-glutathionylation/deglutathionylation and S-nitrosylation/denitrosylation, respectively, and depends on the cellular redox status. The extent of S-glutathionylation and S-nitrosylation of protein targets and their ratio largely determine the status and direction of signaling pathways in cancer cells. The review discusses the features of S-glutathionylation and S-nitrosylation reactions and systems that control them in cancer cells, as well as their relationship with redox-dependent processes and tumor growth.

Increased insulin resistance due to Long COVID is associated with depressive symptoms and partly predicted by the inflammatory response during acute infection

OBJECTIVE

Some months after the remission of acute COVID-19, some individuals show depressive symptoms, which are predicted by increased peak body temperature (PBT) and decreased blood oxygen saturation (SpO2). The present study aimed to examine data on whether long COVID is associated with increased insulin resistance (IR) in association with neuroimmune and oxidative (NIO) processes during the acute infectious and long COVID phases.

METHODS

This case-control, retrospective cohort study used the Homeostasis Model Assessment 2 (HOMA2) calculator© to compute ß-cell function (HOMA2%B) and insulin sensitivity (HOMA2%S) and resistance (HOMA2-IR) and administered the Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HAMD) to 86 patients with long COVID and 39 controls.

RESULTS

Long COVID (3-4 months after the acute infection) is accompanied by increased HOMA2-IR, fasting blood glucose (FBG), and insulin levels; 33.7% of the patients vs. 0% of the controls had HOMA2-IR values > 1.8, suggesting IR. Increased IR was predicted by PBT during acute infection and associated with depressive symptoms above and beyond the effects of NIO pathways (nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing protein 3 [NLRP3] inflammasome, myeloperoxidase [MPO], protein oxidation). There were no significant associations between increased IR and the activated NIO pathways during long COVID.

CONCLUSION

Long COVID is associated with new-onset IR, which may contribute to onset of depressive symptoms due to long COVID by enhancing overall neurotoxicity.

Exploration of the Gut Microbiome in Thai Patients with Major Depressive Disorder Shows a Specific Bacterial Profile with Depletion of the Ruminococcus Genus as a Putative Biomarker

Maes et al. (2008) published the first paper demonstrating that major depressive disorder (MDD) is accompanied by abnormalities in the microbiota-gut-brain axis, as evidenced by elevated serum IgM/IgA to lipopolysaccharides (LPS) of Gram-negative bacteria, such as Morganella morganii and Klebsiella Pneumoniae. The latter aberrations, which point to increased gut permeability (leaky gut), are linked to activated neuro-immune and oxidative pathways in MDD. To delineate the profile and composition of the gut microbiome in Thai patients with MDD, we examined fecal samples of 32 MDD patients and 37 controls using 16S rDNA sequencing, analyzed α- (Chao1 and Shannon indices) and β-diversity (Bray-Curtis dissimilarity), and conducted linear discriminant analysis (LDA) effect size (LEfSe) analysis. Neither α- nor β-diversity differed significantly between MDD and controls. Rhodospirillaceae, Hungatella, Clostridium bolteae, Hungatella hathewayi, and Clostridium propionicum were significantly enriched in MDD, while Gracillibacteraceae family, Lutispora, and Ruminococcus genus, Ruminococcus callidus, Desulfovibrio piger, Coprococcus comes, and Gemmiger were enriched in controls. Contradictory results have been reported for all these taxa, with the exception of Ruminococcus, which is depleted in six different MDD studies (one study showed increased abundance), many medical disorders that show comorbidities with MDD, and animal MDD models. Our results may suggest a specific profile of compositional gut dysbiosis in Thai MDD patients, with increases in some pathobionts and depletion of some beneficial microbiota. The results suggest that depletion of Ruminococcus may be a more universal biomarker of MDD that may contribute to increased enteral LPS load, LPS translocation, and gut-brain axis abnormalities.

Cellular Stress Response (Hormesis) in Response to Bioactive Nutraceuticals with Relevance to Alzheimer Disease

Significance: Alzheimer's disease (AD) is the most common form of dementia associated with aging. As the large Baby Boomer population ages, risk of developing AD increases significantly, and this portion of the population will increase significantly over the next several decades. Recent Advances: Research suggests that a delay in the age of onset by 5 years can dramatically decrease both the incidence and cost of AD. In this review, the role of nuclear factor erythroid 2-related factor 2 (Nrf2) in AD is examined in the context of heme oxygenase-1 (HO-1) and biliverdin reductase-A (BVR-A) and the beneficial potential of selected bioactive nutraceuticals. Critical Issues: Nrf2, a transcription factor that binds to enhancer sequences in antioxidant response elements (ARE) of DNA, is significantly decreased in AD brain. Downstream targets of Nrf2 include, among other proteins, HO-1. BVR-A is activated when biliverdin is produced. Both HO-1 and BVR-A also are oxidatively or nitrosatively modified in AD brain and in its earlier stage, amnestic mild cognitive impairment (MCI), contributing to the oxidative stress, altered insulin signaling, and cellular damage observed in the pathogenesis and progression of AD. Bioactive nutraceuticals exhibit anti-inflammatory, antioxidant, and neuroprotective properties and are potential topics of future clinical research. Specifically, ferulic acid ethyl ester, sulforaphane, epigallocatechin-3-gallate, and resveratrol target Nrf2 and have shown potential to delay the progression of AD in animal models and in some studies involving MCI patients. Future Directions: Understanding the regulation of Nrf2 and its downstream targets can potentially elucidate therapeutic options for delaying the progression of AD. Antioxid. Redox Signal. 38, 643-669.

[Plasma acid reproduces oxidative and nitrosative stress in bladder tissue in vitro: experimental study]

AIM

To analyze some effects of plasma acid in vitro on the bladder tissue obtained from laboratory animals and to evaluate the possibility of its application for in vitro modeling of IC/BPS.

MATERIALS AND METHODS

The tissue samples of the bladder wall were obtained from female Wistar rats aged 3 months (n=16, weighing 180-200 g). The tissues were processed for 1 hour in the plasma acid prepared by spark discharge of water for injection in air. The immunohistochemical study of obtained samples was performed.

RESULTS

The changes in the expression profile of bladder epithelial cells under the action of plasma acid in vitro were found indicating the development of oxidative, nitrosative and dicarbonyl stress, impaired expression of NADPH oxidase DUOX2 and VEGF, and a decrease in cell proliferative activity, which, in general, corresponds to the main mechanisms of urothelial alterations specific for the IC/BPS.

CONCLUSION

The revealed effects of plasma acid on bladder epithelial cells confirm the possibility of using it as an inducer of urothelial cell damage typical for IC/BPS in the in vitro models.

Increased Lipid Peroxidation and Lowered Antioxidant Defenses Predict Methamphetamine Induced Psychosis

BACKGROUND

a significant percentage of methamphetamine (MA) dependent patients develop psychosis. The associations between oxidative pathways and MA-induced psychosis (MIP) are not well delineated.

OBJECTIVE

the aim of this study is to delineate whether acute MA intoxication in MA dependent patients is accompanied by increased nitro-oxidative stress and whether the latter is associated with MIP.

METHOD

we recruited 30 healthy younger males and 60 acutely intoxicated males with MA dependence and assessed severity of MA use and dependence and psychotic symptoms during intoxication, and serum oxidative toxicity (OSTOX) biomarkers including oxidized high (oxHDL) and low (oxLDL)-density lipoprotein, myeloperoxidase (MPO), malondialdehyde (MDA), and nitric oxide (NO), and antioxidant defenses (ANTIOX) including HDL-cholesterol, zinc, glutathione peroxidase (GPx), total antioxidant capacity (TAC), and catalase-1.

RESULTS

a large part (50%, n = 30) of patients with MA dependence could be allocated to a cluster characterized by high psychosis ratings including delusions, suspiciousness, conceptual disorganization and difficulties abstract thinking and an increased OSTOX/ANTIOX ratio. Partial Least Squares analysis showed that 29.9% of the variance in MIP severity (a first factor extracted from psychosis, hostility, excitation, mannerism, and formal thought disorder scores) was explained by HDL, TAC and zinc (all inversely) and oxLDL (positively). MA dependence and dosing explained together 44.7% of the variance in the OSTOX/ANTIOX ratio.

CONCLUSIONS

MA dependence and intoxication are associated with increased oxidative stress and lowered antioxidant defenses, both of which increase risk of MIP during acute intoxication. MA dependence is accompanied by increased atherogenicity due to lowered HDL and increased oxLDL and oxHDL.

Deltamethrin-Evoked ER Stress Promotes Neuroinflammation in the Adult Mouse Hippocampus

Endoplasmic reticulum (ER) stress and neuroinflammation are involved in the pathogenesis of many neurodegenerative disorders. Previously, we reported that exposure to pyrethroid insecticide deltamethrin causes hippocampal ER stress apoptosis, a reduction in neurogenesis, and learning deficits in adult male mice. Recently, we found that deltamethrin exposure also increases the markers of neuroinflammation in BV2 cells. Here, we investigated the potential mechanistic link between ER stress and neuroinflammation following exposure to deltamethrin. We found that repeated oral exposure to deltamethrin (3 mg/kg) for 30 days caused microglial activation and increased gene expressions and protein levels of TNF-α, IL-1β, IL-6, gp91^phox, 4HNE, and iNOS in the hippocampus. These changes were preceded by the induction of ER stress as the protein levels of CHOP, ATF-4, and GRP78 were significantly increased in the hippocampus. To determine whether induction of ER stress triggers the inflammatory response, we performed an additional experiment with mouse microglial cell (MMC) line. MMCs were treated with 0–5 µM deltamethrin for 24–48 h in the presence or absence of salubrinal, a pharmacological inhibitor of the ER stress factor eIF2α. We found that salubrinal (50 µM) prevented deltamethrin-induced ER stress, as indicated by decreased levels of CHOP and ATF-4, and attenuated the levels of GSH, 4-HNE, gp91^phox, iNOS, ROS, TNF-α, IL-1β, and IL-6 in MMCs. Together, these results demonstrate that exposure to deltamethrin leads to ER stress-mediated neuroinflammation, which may subsequently contribute to neurodegeneration and cognitive impairment in mice.

Aberrations in the Cross-Talks Among Redox, Nuclear Factor-κB, and Wnt/β-Catenin Pathway Signaling Underpin Myalgic Encephalomyelitis and Chronic Fatigue Syndrome

There is evidence that chronic fatigue spectrum disorders (CFAS-Ds), including myalgic encephalomyelitis (ME), chronic fatigue syndrome (CFS), and chronic fatigue with physiosomatic symptoms including when due to comorbid medical disease, are characterized by neuroimmune and neuro-oxidative biomarkers. This study was performed to delineate the protein-protein interaction (PPI) network of CFAS-D and to discover the pathways, molecular patterns, and domains enriched in their PPI network. We performed network, enrichment, and annotation analyses using differentially expressed proteins and metabolics, which were established in patients with CFAS-D. The PPI network analysis revealed that the backbone of the highly connective CFAS-D network comprises NFKB1, CTNNB1, ALB, peroxides, NOS2, tumor necrosis factor (TNF), and interleukin-6 (IL-6) and that the network comprises interconnected immune-oxidative-nitrosative and Wnt/β-catenin subnetworks. Multiomics enrichment analysis shows that the CFAS-D network is highly significantly associated with cellular (antioxidant) detoxification, hydrogen peroxide metabolic process, peroxidase and oxidoreductase activity, interleukin-10 (IL-10) anti-inflammatory signaling and neurodegenerative canonical Wnt, the β-catenin complex, cadherin domains, cell-cell junctions and TLR2/4 pathways, and the transcription factors nuclear factor kappa B (NF-κB) and RELA. The top 10 DOID annotations of the CFAS-D network include four intestinal, three immune system disorders, cancer, and infectious disease. The custom Gene Ontology (GO) term annotation analysis revealed that the CFAS-D network is associated with a response to a toxic substance, lipopolysaccharides, bacterium, or virus. In conclusion, CFAS-D may be triggered by a variety of stimuli and their effects are mediated by aberrations in the cross-talks between redox, NF-κB, and Wnt/β-catenin signaling pathways leading to dysfunctions in multicellular organismal homeostatic processes.

Melatonin as a Potential Regulator of Oxidative Stress, and Neuroinflammation: Mechanisms and Implications for the Management of Brain Injury-Induced Neurodegeneration

This review covers the preclinical and clinical literature supporting the role of melatonin in the management of brain injury-induced oxidative stress, neuroinflammation, and neurodegeneration, and reviews the past and current therapeutic strategies. Traumatic brain injury (TBI) is a neurodegenerative condition, unpredictably and potentially progressing into chronic neurodegeneration, with permanent cognitive, neurologic, and motor dysfunction, having no standard therapies. Due to its complex and multi-faceted nature, the TBI has highly heterogeneous pathophysiology, characterized by the highest mortality and disability worldwide. Mounting evidence suggests that the TBI induces oxidative and nitrosative stress, which is involved in the progression of chronic and acute neurodegenerative diseases. Defenses against such conditions are mostly dependent on the usage of antioxidant compounds, the majority of whom are ingested as nutraceuticals or as dietary supplements. A large amount of literature is available regarding the efficacy of antioxidant compounds to counteract the TBI-associated damage in animal and cellular models of the TBI and several clinical studies. Collectively, the studies have suggested that TBI induces oxidative stress, by suppressing the endogenous antioxidant system, such as nuclear factor erythroid 2–related factor-2 (Nrf-2) increasing the lipid peroxidation and elevation of oxidative damage. Moreover, elevated oxidative stress may induce neuroinflammation by activating the microglial cells, releasing and activating the inflammatory cytokines and inflammatory mediators, and energy dyshomeostasis. Thus, melatonin has shown regulatory effects against the TBI-induced autophagic dysfunction, regulation of mitogen-activated protein kinases, such as ERK, activation of the NLRP-3 inflammasome, and release of the inflammatory cytokines. The collective findings strongly suggest that melatonin may regulate TBI-induced neurodegeneration, although further studies should be conducted to better facilitate future therapeutic windows.

Continuous Monitoring Reveals Protective Effects of N-Acetylcysteine Amide on an Isogenic Microphysiological Model of the Neurovascular Unit

Microphysiological systems mimic the in vivo cellular ensemble and microenvironment with the goal of providing more human-like models for biopharmaceutical research. In this study, the first such model of the blood-brain barrier (BBB-on-chip) featuring both isogenic human induced pluripotent stem cell (hiPSC)-derived cells and continuous barrier integrity monitoring with <2 min temporal resolution is reported. Its capabilities are showcased in the first microphysiological study of nitrosative stress and antioxidant prophylaxis. Relying on off-stoichiometry thiol-ene-epoxy (OSTE+) for fabrication greatly facilitates assembly and sensor integration compared to the prevalent polydimethylsiloxane devices. The integrated cell-substrate endothelial resistance monitoring allows for capturing the formation and breakdown of the BBB model, which consists of cocultured hiPSC-derived endothelial-like and astrocyte-like cells. Clear cellular disruption is observed when exposing the BBB-on-chip to the nitrosative stressor linsidomine, and the barrier permeability and barrier-protective effects of the antioxidant N-acetylcysteine amide are reported. Using metabolomic network analysis reveals further drug-induced changes consistent with prior literature regarding, e.g., cysteine and glutathione involvement. A model like this opens new possibilities for drug screening studies and personalized medicine, relying solely on isogenic human-derived cells and providing high-resolution temporal readouts that can help in pharmacodynamic studies.

Deficit schizophrenia and its features are associated with PON1 Q192R genotypes and lowered paraoxonase 1 (PON1) enzymatic activity: effects on bacterial translocation

BACKGROUND

Primary deficit schizophrenia (DS) is characterized by enduring negative symptoms and represents a qualitatively different disease entity with respect to non-deficit schizophrenia (NDS). No studies investigated the association between the enzyme paraoxonase 1 (PON1) and DS and its phenomenology.

METHODS

In this case-control study, Thai women and men, aged 18 to 65 years, were divided in DS (n = 40) and NDS (n = 40) and were compared to controls (n = 40). PON1 activities against 4-(chloromethyl)phenyl acetate (CMPA) and phenylacetate were determined. Moreover, subjects were genotyped for their PON1 Q192R polymorphism and immunoglobulin A (IgA) levels responses directed to Gram-negative bacteria were measured.

RESULTS

DS is significantly associated with the QQ genotype and the Q allele as compared with NDS and controls. PON1 activities are significantly and inversely associated with negative symptoms, formal thought disorders, psychomotor retardation, excitation and DS. The presence of the Q allele is associated with increased IgA responses to Pseudomonas aeruginosa, Morganella morganii, and Pseudomonas putida as compared with RR carriers.

CONCLUSIONS

The PON1 Q allele and lower PON1 activities especially against CMPA are associated with DS, indicating lowered quorum quenching abilities as well as lowered defenses against lipoperoxidation and immune activation. It is suggested that lowered PON1 activity in DS constitutes an impairment in the innate immune system which together with lowered natural IgM may cause lower immune regulation thereby predisposing toward greater neurotoxic effects of immune-inflammatory, oxidative and nitrosative pathways and Gram-negative microbiota.

The reification of the clinical diagnosis of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) as an immune and oxidative stress disorder: construction of a data-driven nomothethic network and exposure of ME/CFS subgroups

The approach towards myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) remains in a permanent state of crisis with fierce competition between the psychosocial school, which attributes ME/CFS to the perception of effort, and the medical approach (Maes and Twisk, BMC Med, 2010,8,35). The aim of this paper is to review how to construct a nomothetic model of ME/CFS using Partial Least Squares (PLS) path analysis and ensembling causome (bacterial translocation as assessed with IgM/IgA responses to LPS), protectome (lowered coenzyme Q10), adverse outcome pathways (AOP) including increased lysozyme, CD38+ T cell activation, cell-mediated immune activation (CMI), and IgM responses to oxidative specific epitopes and NO-adducts (IgM OSENO). Using PLS, we trained, tested and validated this knowledge- and data-driven causal ME/CFS model, which showed adequate convergence, construct and replicability validity. This bottom-up explicit data model of ME/CFS objectivates the descriptive narratives of the ME/CFS phenome, using causome-protectome-AOP data, whereby the abstract concept ME/CFS is translated into pathways, thereby securing the reification of the ME/CFS phenome. We found that 31.6% of the variance in the physiosomatic symptom dimension of ME/CFS was explained by the cumulative effects of CMI and CD38+ activation, IgM OSENO, IgA LPS, lysozyme (all positive) and coenzyme Q10 (inversely). Cluster analysis performed on the PLS-generated latent vector scores of all feature sets exposed three distinct immune groups of ME/CFS, namely one with increased lysozyme, one with increased CMI + CD38 activation + depressive symptoms, and another with increased bacterial translocation + autoimmune responses to OSENO.

Theory: Treatments for Prolonged ICU Patients May Provide New Therapeutic Avenues for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

We here provide an overview of treatment trials for prolonged intensive care unit (ICU) patients and theorize about their relevance for potential treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Specifically, these treatment trials generally target: (a) the correction of suppressed endocrine axes, notably through a "reactivation" of the pituitary gland's pulsatile secretion of tropic hormones, or (b) the interruption of the "vicious circle" between inflammation, oxidative and nitrosative stress (O&NS), and low thyroid hormone function. There are significant parallels in the treatment trials for prolonged critical illness and ME/CFS; this is consistent with the hypothesis of an overlap in the mechanisms that prevent recovery in both conditions. Early successes in the simultaneous reactivation of pulsatile pituitary secretions in ICU patients-and the resulting positive metabolic effects-could indicate an avenue for treating ME/CFS. The therapeutic effects of thyroid hormones-including in mitigating O&NS and inflammation and in stimulating the adreno-cortical axis-also merit further studies. Collaborative research projects should further investigate the lessons from treatment trials for prolonged critical illness for solving ME/CFS.

Analysis and Optimization of Conditions for the Use of 2',7'-Dichlorofluorescein Diacetate in Cultured Hepatocytes

Numerous liver pathologies encompass oxidative stress as molecular basis of disease. The use of 2',7'-dichlorodihydrofluorescein-diacetate (DCFH₂-DA) as fluorogenic redox probe is problematic in liver cell lines because of membrane transport proteins that interfere with probe kinetics, among other reasons. The properties of DCFH₂-DA were analyzed in hepatocytes (HepG2, HepaRG) to characterize methodological issues that could hamper data interpretation and falsely skew conclusions. Experiments were focused on probe stability in relevant media, cellular probe uptake/retention/excretion, and basal oxidant formation and metabolism. DCFH₂-DA was used under optimized experimental conditions to intravitally visualize and quantify oxidative stress in real-time in HepG2 cells subjected to anoxia/reoxygenation. The most important findings were that: (1) the non-fluorescent DCFH₂-DA and the fluorescent DCF are rapidly taken up by hepatocytes, (2) DCF is poorly retained in hepatocytes, and (3) DCFH₂ oxidation kinetics are cell type-specific. Furthermore, (4) DCF fluorescence intensity was pH-dependent at pH < 7 and (5) the stability of DCFH₂-DA in cell culture medium relied on medium composition. The use of DCFH₂-DA to measure oxidative stress in cultured hepatocytes comes with methodological and technical challenges, which were characterized and solved. Optimized in vitro and intravital imaging protocols were formulated to help researchers conduct proper experiments and draw robust conclusions.

Hypothesis: Mechanisms That Prevent Recovery in Prolonged ICU Patients Also Underlie Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Here the hypothesis is advanced that maladaptive mechanisms that prevent recovery in some intensive care unit (ICU) patients may also underlie Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Specifically, these mechanisms are: (a) suppression of the pituitary gland's pulsatile secretion of tropic hormones, and (b) a "vicious circle" between inflammation, oxidative and nitrosative stress (O&NS), and low thyroid hormone function. This hypothesis should be investigated through collaborative research projects.

Mitochondrial Oxidative and Nitrosative Stress and Alzheimer Disease

Oxidative and nitrosative stress are widely recognized as critical factors in the pathogenesis and progression of Alzheimer disease (AD) and its earlier stage, amnestic mild cognitive impairment (MCI). A major source of free radicals that lead to oxidative and nitrosative damage is mitochondria. This review paper discusses oxidative and nitrosative stress and markers thereof in the brain, along with redox proteomics, which are techniques that have been pioneered in the Butterfield laboratory. Selected biological alterations in-and oxidative and nitrosative modifications of-mitochondria in AD and MCI and systems of relevance thereof also are presented. The review article concludes with a section on the implications of mitochondrial oxidative and nitrosative stress in MCI and AD with respect to imaging studies in and targeted therapies toward these disorders. Taken together, this review provides support for the notion that brain mitochondrial alterations in AD and MCI are key components of oxidative and nitrosative stress observed in these two disorders, and as such, they provide potentially promising therapeutic targets to slow-and hopefully one day stop-the progression of AD, which is a devastating dementing disorder.

Combined treatment of menadione and calcitriol increases the antiproliferative effect by promoting oxidative/nitrosative stress, mitochondrial dysfunction, and autophagy in breast cancer MCF-7 cells

The aim of this study was to determine new insights into the molecular mechanisms involved in the antiproliferative action of menadione + calcitriol (MEN+D) on MCF-7 cells. After 24 h, MEN+D inhibited the cell growth but was not observed with each single treatment. The combined drugs reduced the mitochondrial respiration at that time, as judged by an increase in the proton leak and a decrease in the ATP generation and coupling efficiency. At longer times, 48 or 96 h, either D or MEN reduced the proliferation, but the effect was higher when both drugs were used together. The combined treatment increased the superoxide anion ([Formula: see text]) and nitric oxide (NO^•) contents as well as acidic vesicular organelles (AVOs) formation. The percentage of cells showing the lower mitochondrial membrane potential (ΔΨ_m) was highly increased by the combined therapy. LC3-II protein expression was enhanced by any treatment. In conclusion, the antiproliferative action of MEN+D involves oxidative/nitrosative stress, mitochondrial alteration, and autophagy. This combined therapy could be useful to treat breast cancer cells because it inhibits multiple oncogenic pathways more effectively than each single agent.

Effects of venlafaxine on the expression level and methylation status of genes involved in oxidative stress in rats exposed to a chronic mild stress

Recent human and animal studies indicate that oxidative and nitrosative stress may play a role in the aetiology and pathogenesis of depression. This study investigates the effect of chronic administration of the serotonin‐norepinephrine reuptake inhibitor, venlafaxine, on the expression and methylation status of SOD1, SOD2, GPx1, GPx4, CAT, NOS1 and NOS2 in the brain and blood of rats exposed to a chronic mild stress (CMS) model of depression. Separate groups of animals were exposed to CMS for 2 or 7 weeks; the second group received saline or venlafaxine (10 mg/kg/d, IP) for 5 weeks. After completion of both stress conditions and drug administration, the mRNA and protein expression of selected genes and the methylation status of their promoters were measured in peripheral mononuclear blood cells (PBMCs) and in brain structures (hippocampus, amygdala, hypothalamus, midbrain, cortex, basal ganglia) with the use of TaqMan Gene Expression Assay, Western blot and methylation‐sensitive high‐resolution melting techniques. CMS caused a decrease in sucrose consumption, and this effect was normalized by fluoxetine. In PBMCs, SOD1, SOD2 and NOS2 mRNA expression changed only after venlafaxine administration. In brain, CAT, Gpx1, Gpx4 and NOS1 gene expression changed following CMS or venlafaxine exposure, most prominently in the hippocampus, midbrain and basal ganglia. CMS increased the methylation of the Gpx1 promoter in PBMCs, the second Gpx4 promoter in midbrain and basal ganglia, and SOD1 and SOD2 in hippocampus. The CMS animals treated with venlafaxine displayed a significantly higher CAT level in midbrain and cerebral cortex. CMS caused an elevation of Gpx4 in the hippocampus, which was lowered in cerebral cortex by venlafaxine. The results indicate that CMS and venlafaxine administration affect the methylation of promoters of genes involved in oxidative and nitrosative stress. They also indicate that peripheral and central tissue differ in their response to stress or antidepressant treatments. It is possible that that apart from DNA methylation, a crucial role of expression level of genes may be played by other forms of epigenetic regulation, such as histone modification or microRNA interference.

These findings provide strong evidence for thesis that analysis of the level of mRNA and protein expression as well as the status of promoter methylation can help in understanding the pathomechanisms of mental diseases, including depression, and the mechanisms of action of drugs effective in their therapy.

Physiological and pathophysiological role of reactive oxygen species and reactive nitrogen species in the kidney

End‐stage renal disease is a leading cause of morbidity and mortality worldwide. The prevalence of the disease and the number of patients who receive renal replacement therapy are expected to increase in the next decade. Accumulating evidence suggests that chronic hypoxia in the tubulointerstitium represents the final common pathway to end‐stage renal failure, and that reactive oxygen species (ROS) and reactive nitrogen species (RNS) are the key players in kidney injury. However, ROS and RNS that exceed the physiological levels associated with the pathophysiology of most kidney diseases. The molecules that comprise ROS and RNS play an important role in regulating solute and water reabsorption in the kidney, which is vital for maintaining electrolyte homeostasis and the volume of extracellular fluid. This article reviews the physiological and pathophysiological role of ROS and RNS in normal kidney function and in various kidney diseases.

Calendula officinalis ameliorates l-arginine-induced acute necrotizing pancreatitis in rats

CONTEXT

Calendula officinalis L. (Asteraceae) has been traditionally used in treating inflammation of internal organs, gastrointestinal tract ulcers and wound healing.

OBJECTIVE

The present study investigates the effect of ethanol extract (95%) of Calendula officinalis flowers in l-arginine induced acute necrotizing pancreatitis in rats.

MATERIALS AND METHODS

Rats were divided into four groups: normal control, l-arginine control, Calendula officinalis extract (COE) treated and melatonin treated (positive control), which were further divided into subgroups (24 h, day 3 and 14) according to time points. Two injections of l-arginine 2 g/kg i.p. at 1 h intervals were administered in l-arginine control, COE and melatonin-treated groups to produce acute necrotizing pancreatitis. Biochemical parameters [serum amylase, lipase, pancreatic amylase, nucleic acid content, total proteins, transforming growth factor-β1 (TGF-β1), collagen content, lipid peroxidation, reduced glutathione and nitrite/nitrate] and histopathological studies were carried out.

RESULTS

COE treatment (400 mg/kg p.o.) was found to be beneficial. This was evidenced by significantly lowered histopathological scores (2 at day 14). Nucleic acid content (DNA 21.1 and RNA 5.44 mg/g pancreas), total proteins (0.66 mg/mL pancreas) and pancreatic amylase (1031.3 100 SU/g pancreas) were significantly improved. Marked reduction in pancreatic oxidative and nitrosative stress; collagen (122 μmoles/100 mg pancreas) and TGF-β1 (118.56 pg/mL) levels were noted. Results obtained were comparable to those of positive control.

DISCUSSION AND CONCLUSION

The beneficial effect of COE may be attributed to its antioxidant, antinitrosative and antifibrotic actions. Hence, the study concludes that COE promotes spontaneous repair and regeneration of the pancreas.

Gender and estrous cycle influences on behavioral and neurochemical alterations in adult rats neonatally administered ketamine

Neonatal N-methyl-D-aspartate (NMDA) receptor blockade in rodents triggers schizophrenia (SCZ)-like alterations during adult life. SCZ is influenced by gender in age of onset, premorbid functioning, and course. Estrogen, the hormone potentially driving the gender differences in SCZ, is known to present neuroprotective effects such as regulate oxidative pathways and the expression of brain-derived neurotrophic factor (BDNF). Thus, the aim of this study was to verify if differences in gender and/or estrous cycle phase during adulthood would influence the development of behavioral and neurochemical alterations in animals neonatally administered ketamine. The results showed that ketamine-treated male (KT-male) and female-in-diestrus (KTF-diestrus, the low estrogen phase) presented significant deficits in prepulse inhibition of the startle reflex and spatial working memory, two behavioral SCZ endophenotypes. On the contrary, female ketamine-treated rats during proestrus (KTF-proestrus, the high estradiol phase) had no behavioral alterations. This correlated with an oxidative imbalance in the hippocampus (HC) of both male and KTF-diestrus female rats, that is, decreased levels of GSH and increased levels of lipid peroxidation and nitrite. Similarly, BDNF was decreased in the KTF-diestrus rats while no alterations were observed in KTF-proestrus and male animals. The changes in the HC were in contrast to those in the prefrontal cortex in which only increased levels of nitrite in all groups studied were observed. Thus, there is a gender difference in the adult rat HC in response to ketamine neonatal administration, which is based on the estrous cycle. This is discussed in relation to neuropsychiatric conditions and in particular SCZ.

Atopic disorders and depression: findings from a large, population-based study

BACKGROUND

Atopy, a common disorder characterized by a sensitivity to allergic reactions, affects a large proportion of the adult population and, as with depression, is associated with immune-inflammatory pathway changes. We sought to determine the role of atopic disorders in depression using data from a randomly-selected, population-based study of men and women.

METHODS

Cross-sectional data derived from the Geelong Osteoporosis Study for 942 males and 1085 females were analyzed. Depression [major depressive disorder (MDD), minor depression and dysthymia] was assessed using the Structured Clinical Interview for DSM-IV-TR Research Version, Non-patient edition. Data on medical conditions, including atopic disorders (asthma, hay fever and eczema), smoking status, alcohol consumption, socioeconomic status, and physical activity were documented by self-report. Logistic regression modeling was used to explore the associations between atopic disorders and depression.

RESULTS

Atopic disorders were associated with a 59% increased likelihood of depression [gender and smoking-adjusted odds ratio (OR) 1:50, 95% CI 1.20-1.97]. Sub-group analyses revealed a similar pattern for those with MDD [gender and smoking-adjusted OR 1:54, 95% CI 1.22-1.94]. These associations were independent of socio-demographic characteristics, clinical and lifestyle factors.

LIMITATIONS

Reliance on self-report for allergic symptoms and cross-sectional nature of study.

CONCLUSION

This population-based study provides evidence of the potential contribution of allergic disorders to depression. Further research is required to elucidate the direction of this association and to further explicate its underlying physiology, including immune-inflammation markers.

Myalgic encephalomyelitis/chronic fatigue syndrome and encephalomyelitis disseminata/multiple sclerosis show remarkable levels of similarity in phenomenology and neuroimmune characteristics

BACKGROUND

'Encephalomyelitis disseminata' (multiple sclerosis) and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are both classified as diseases of the central nervous system by the World Health Organization. This review aims to compare the phenomenological and neuroimmune characteristics of MS with those of ME/CFS.

DISCUSSION

There are remarkable phenomenological and neuroimmune overlaps between both disorders. Patients with ME/CFS and MS both experience severe levels of disabling fatigue and a worsening of symptoms following exercise and resort to energy conservation strategies in an attempt to meet the energy demands of day-to-day living. Debilitating autonomic symptoms, diminished cardiac responses to exercise, orthostatic intolerance and postural hypotension are experienced by patients with both illnesses. Both disorders show a relapsing-remitting or progressive course, while infections and psychosocial stress play a large part in worsening of fatigue symptoms. Activated immunoinflammatory, oxidative and nitrosative (O+NS) pathways and autoimmunity occur in both illnesses. The consequences of O+NS damage to self-epitopes is evidenced by the almost bewildering and almost identical array of autoantibodies formed against damaged epitopes seen in both illnesses. Mitochondrial dysfunctions, including lowered levels of ATP, decreased phosphocreatine synthesis and impaired oxidative phosphorylation, are heavily involved in the pathophysiology of both MS and ME/CFS. The findings produced by neuroimaging techniques are quite similar in both illnesses and show decreased cerebral blood flow, atrophy, gray matter reduction, white matter hyperintensities, increased cerebral lactate and choline signaling and lowered acetyl-aspartate levels.

SUMMARY

This review shows that there are neuroimmune similarities between MS and ME/CFS. This further substantiates the view that ME/CFS is a neuroimmune illness and that patients with MS are immunologically primed to develop symptoms of ME/CFS.

Neurogenic inflammation and cardiac dysfunction due to hypomagnesemia

Hypomagnesemia continues to be a significant clinical disorder that is present in patients with diabetes mellitus, alcoholism, and treatment with magnesuric drugs (diuretics, cancer chemotherapy agents, etc.). To determine the role of magnesium in cardiovascular pathophysiology, we have used dietary restriction of this cation in animal models. This review highlights some key observations that helped formulate the hypothesis that release of substance P (SP) during experimental dietary Mg deficiency (MgD) may initiate a cascade of deleterious inflammatory, oxidative, and nitrosative events, which ultimately promote cardiomyopathy, in situ cardiac dysfunction, and myocardial intolerance to secondary stresses. SP acts primarily through neurokinin-1 receptors of inflammatory and endothelial cells, and may induce production of reactive oxygen and nitrogen species (superoxide anion, NO*, peroxynitrite, hydroxyl radical), leading to enhanced consumption of tissue antioxidants; stimulate release of inflammatory mediators; promote tissue adhesion molecule expression; and enhance inflammatory cell tissue infiltration and cardiovascular lesion formation. These SP-mediated events may predispose the heart to injury if faced with subsequent oxidative stressors (ischemia/reperfusion, certain drugs) or facilitate development of in situ cardiac dysfunction, especially with prolonged dietary Mg restriction. Significant protection against most of these MgD-mediated events has been observed with interventions that modulate neuronal SP release or its bioactivity, and with several antioxidants (vitamin E, probucol, epicaptopril, d-propranolol). In view of the clinical prevalence of hypomagnesemia, new treatments, beyond magnesium repletion, may be needed to diminish deleterious neurogenic and prooxidative components described in this article.