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1.
Comput Struct Biotechnol J ; 24: 322-333, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38690549

ABSTRACT

Data curation for a hospital-based cancer registry heavily relies on the labor-intensive manual abstraction process by cancer registrars to identify cancer-related information from free-text electronic health records. To streamline this process, a natural language processing system incorporating a hybrid of deep learning-based and rule-based approaches for identifying lung cancer registry-related concepts, along with a symbolic expert system that generates registry coding based on weighted rules, was developed. The system is integrated with the hospital information system at a medical center to provide cancer registrars with a patient journey visualization platform. The embedded system offers a comprehensive view of patient reports annotated with significant registry concepts to facilitate the manual coding process and elevate overall quality. Extensive evaluations, including comparisons with state-of-the-art methods, were conducted using a lung cancer dataset comprising 1428 patients from the medical center. The experimental results illustrate the effectiveness of the developed system, consistently achieving F1-scores of 0.85 and 1.00 across 30 coding items. Registrar feedback highlights the system's reliability as a tool for assisting and auditing the abstraction. By presenting key registry items along the timeline of a patient's reports with accurate code predictions, the system improves the quality of registrar outcomes and reduces the labor resources and time required for data abstraction. Our study highlights advancements in cancer registry coding practices, demonstrating that the proposed hybrid weighted neural-symbolic cancer registry system is reliable and efficient for assisting cancer registrars in the coding workflow and contributing to clinical outcomes.

2.
Biol Psychiatry Glob Open Sci ; 4(3): 100306, 2024 May.
Article in English | MEDLINE | ID: mdl-38628385

ABSTRACT

Background: Accumulating evidence underscores the pivotal role of heightened inflammation in the pathophysiology of stress-related diseases, but the underlying mechanisms remain elusive. The complement system, a key effector of the innate immune system, produces the C5-cleaved activation product C5a upon activation, initiating inflammatory responses through the canonical C5a receptor 1 (C5aR1). While C5aR1 is expressed in stress-responsive brain regions, its role in stress responsiveness remains unknown. Methods: To investigate C5a-C5aR1 signaling in stress responses, mice underwent acute and chronic stress paradigms. Circulating C5a levels and messenger RNA expression of C5aR1 in the hippocampus and adrenal gland were measured. C5aR1-deficient mice were used to elucidate the effects of disrupted C5a-C5aR1 signaling across behavioral, hormonal, metabolic, and inflammation parameters. Results: Chronic restraint stress elevated circulating C5a levels while reducing C5aR1 messenger RNA expression in the hippocampus and adrenal gland. Notably, the absence of C5aR1 signaling enhanced adrenal sensitivity to adrenocorticotropic hormone, concurrently reducing pituitary adrenocorticotropic hormone production and enhancing the response to acute stress. C5aR1-deficient mice exhibited attenuated reductions in locomotor activity and body weight under chronic stress. Additionally, these mice displayed increased glucocorticoid receptor sensitivity and disrupted glucose and insulin homeostasis. Chronic stress induced an increase in C5aR1-expressing microglia in the hippocampus, a response mitigated in C5aR1-deficient mice. Conclusions: C5a-C5aR1 signaling emerges as a key metabolic regulator during stress, suggesting that complement activation and dysfunctional C5aR1 signaling may contribute to neuroinflammatory phenotypes in stress-related disorders. The results advocate for further exploration of complement C5aR1 as a potential therapeutic target for stress-related conditions.


How the immune system, particularly the complement system, influences responses to stress has not been fully clear. In this study, we focus on C5a-C5aR1 signaling, a part of the immune system, and found that it significantly affects stress-related reactions in mice. In chronic stress, we observed increased inflammation, altered hormonal responses, and disrupted metabolic regulation. Mice lacking C5aR1 showed reduced stress-induced behavioral changes, indicating that this receptor may play a vital role in modulating the stress response. Understanding these immune mechanisms sheds light on stress-related disorders and may open avenues for therapeutic interventions.

3.
Nat Genet ; 56(4): 579-584, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38575728

ABSTRACT

Obesity is a major risk factor for many common diseases and has a substantial heritable component. To identify new genetic determinants, we performed exome-sequence analyses for adult body mass index (BMI) in up to 587,027 individuals. We identified rare loss-of-function variants in two genes (BSN and APBA1) with effects substantially larger than those of well-established obesity genes such as MC4R. In contrast to most other obesity-related genes, rare variants in BSN and APBA1 were not associated with normal variation in childhood adiposity. Furthermore, BSN protein-truncating variants (PTVs) magnified the influence of common genetic variants associated with BMI, with a common variant polygenic score exhibiting an effect twice as large in BSN PTV carriers than in noncarriers. Finally, we explored the plasma proteomic signatures of BSN PTV carriers as well as the functional consequences of BSN deletion in human induced pluripotent stem cell-derived hypothalamic neurons. Collectively, our findings implicate degenerative processes in synaptic function in the etiology of adult-onset obesity.


Subject(s)
Diabetes Mellitus, Type 2 , Induced Pluripotent Stem Cells , Liver Diseases , Nerve Tissue Proteins , Adult , Humans , Adaptor Proteins, Signal Transducing/genetics , Diabetes Mellitus, Type 2/genetics , Genetic Predisposition to Disease , Nerve Tissue Proteins/genetics , Obesity/complications , Obesity/genetics , Proteomics
4.
EMBO Rep ; 25(1): 351-377, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38177913

ABSTRACT

Hypothalamic Adult Neurogenesis (hAN) has been implicated in regulating energy homeostasis. Adult-generated neurons and adult Neural Stem Cells (aNSCs) in the hypothalamus control food intake and body weight. Conversely, diet-induced obesity (DIO) by high fat diets (HFD) exerts adverse influence on hAN. However, the effects of anti-obesity compounds on hAN are not known. To address this, we administered a lipidized analogue of an anti-obesity neuropeptide, Prolactin Releasing Peptide (PrRP), so-called LiPR, to mice. In the HFD context, LiPR rescued the survival of adult-born hypothalamic neurons and increased the number of aNSCs by reducing their activation. LiPR also rescued the reduction of immature hippocampal neurons and modulated calcium dynamics in iPSC-derived human neurons. In addition, some of these neurogenic effects were exerted by another anti-obesity compound, Liraglutide. These results show for the first time that anti-obesity neuropeptides influence adult neurogenesis and suggest that the neurogenic process can serve as a target of anti-obesity pharmacotherapy.


Subject(s)
Neuropeptides , Obesity , Mice , Humans , Animals , Prolactin-Releasing Hormone/pharmacology , Prolactin-Releasing Hormone/therapeutic use , Obesity/drug therapy , Body Weight , Neurogenesis , Hypothalamus
5.
Curr Protoc ; 3(6): e786, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37272700

ABSTRACT

Neurons in the hypothalamus orchestrate homeostatic physiological processes and behaviors essential for life. Human pluripotent stem cells (hPSCs) can be differentiated into many types of hypothalamic neurons, progenitors, and glia. This updated unit includes published studies and protocols with new advances in the differentiation, maturation, and interrogation by transcriptomic profiling and calcium imaging of human hypothalamic cell populations. Specifically, new methods to freeze and thaw hypothalamic progenitors after they have been patterned and before substantial neurogenesis has occurred are provided that will facilitate experimental flexibility and planning. Also included are updated recipes and protocols for neuronal maturation, with details on the equipment and methods for examining their transcriptomic response and cell-autonomous properties in culture in the presence of synaptic blockers. Together, these protocols facilitate the adoption and use of this model system for fundamental biological discovery and therapeutic translation to human diseases such as obesity, diabetes, sleep disorders, infertility, and chronic stress. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: hPSC maintenance Basic Protocol 2: Hypothalamic neuron differentiation Support Protocol 1: Cortical neuron (control) differentiation Basic Protocol 3: Neuronal maturation Support Protocol 2: Cryopreservation and thawing of neuronal progenitors Support Protocol 3: Quality control: Confirmation of hypothalamic patterning and neurogenesis Support Protocol 4: Bulk RNA sequencing of hypothalamic cultures Basic Protocol 4: Calcium imaging of hypothalamic neurons using Fura-2 AM Alternate Protocol: Calcium imaging of green fluorescent hypothalamic neurons using Rhod-3 AM.


Subject(s)
Neurons , Transcriptome , Humans , Neurons/physiology , Cell Differentiation/physiology , Hypothalamus/diagnostic imaging , Neurogenesis/genetics , Calcium, Dietary
6.
PLoS Pathog ; 19(4): e1011309, 2023 04.
Article in English | MEDLINE | ID: mdl-37104170

ABSTRACT

Prion diseases, also known as transmissible spongiform encephalopathies, are rare, progressive, and fatal neurodegenerative disorders, which are caused by the accumulation of the misfolded cellular prion protein (PrPC). The resulting cytotoxic prion species, referred to as the scrapie prion isoform (PrPSc), assemble in aggregates and interfere with neuronal pathways, ultimately rendering neurons dysfunctional. As the prion protein physiologically interacts with redox-active metals, an altered redox balance within the cell can impact these interactions, which may lead to and facilitate further misfolding and aggregation. The initiation of misfolding and the aggregation processes will, in turn, induce microglial activation and neuroinflammation, which leads to an imbalance in cellular redox homeostasis and enhanced redox stress. Potential approaches for therapeutics target redox signalling, and this review illustrates the pathways involved in the above processes.


Subject(s)
Prion Diseases , Prions , Scrapie , Animals , Sheep , Prion Proteins/metabolism , Prions/metabolism , Scrapie/pathology , Oxidation-Reduction
7.
Free Radic Biol Med ; 192: 182-190, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36170956

ABSTRACT

Neurodegenerative diseases are associated with a multitude of dysfunctional cellular pathways. One major contributory factor is a redox stress challenge during the development of several protein misfolding conditions including Alzheimer's (AD), Parkinson's disease (PD), and less common conditions such as Creutzfeldt Jakob disease (CJD). CJD is caused by misfolding of the neuronal prion protein and is characterised by a neurotoxic unfolded protein response involving chronic endoplasmic reticulum stress, reduced protein translation and spongiosis leading subsequently to synaptic and neuronal loss. Here we have characterised prion disease in mice to assess redox stress components including nitrergic and oxidative markers associated with neuroinflammatory activation. Aberrant regulation of the homeostasis of several redox metals contributes to the overall cellular redox stress and we have identified altered levels of iron, copper, zinc, and manganese in the hippocampus of prion diseased mice. Our data show that early in disease, there is evidence for oxidative stress in conjunction with reduced antioxidant superoxide dismutase mRNA and protein expression. Moreover, expression of divalent metal transporter proteins was reduced for Atp7b, Atox1, Slc11a2, Slc39a14 at 6-7 weeks but increased for Slc39a14 and Mt1 at 10 weeks of disease. Our data present evidence for a strong pro-oxidant environment and altered redox metal homeostasis in early disease pathology which both may be contributory factors to aggravating this protein misfolding disease.


Subject(s)
Creutzfeldt-Jakob Syndrome , Prion Diseases , Prions , Animals , Antioxidants/metabolism , Cation Transport Proteins , Copper , Creutzfeldt-Jakob Syndrome/pathology , Homeostasis , Iron , Manganese , Metals/metabolism , Mice , Oxidation-Reduction , Prion Diseases/genetics , Prion Diseases/metabolism , Prion Diseases/pathology , Prion Proteins/metabolism , Prions/metabolism , RNA, Messenger/metabolism , Reactive Oxygen Species , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , Zinc
8.
Antioxidants (Basel) ; 11(1)2021 Dec 29.
Article in English | MEDLINE | ID: mdl-35052588

ABSTRACT

Essential metals such as copper, iron, and zinc are cofactors in various biological processes including oxygen utilisation, cell growth, and biomolecular synthesis. The homeostasis of these essential metals is carefully controlled through a system of protein transporters involved in the uptake, storage, and secretion. Some metal ions can be transformed by processes including reduction/oxidation (redox) reactions, and correspondingly, the breakdown of metal ion homeostasis can lead to formation of reactive oxygen and nitrogen species. We have previously demonstrated rapid biochemical responses to stress involving alterations in the redox state to generate free radicals and the resultant oxidative stress. However, the effects of stress on redox-active metals including iron and copper and redox-inert zinc have not been well characterised. Therefore, this study aims to examine the changes in these essential metals following exposure to short-term repeated stress, and to further elucidate the alterations in metal homeostasis through expression analysis of different metal transporters. Outbred male Wistar rats were exposed to unrestrained (control), 1 day, or 3 days of 6 h restraint stress (n = 8 per group). After the respective stress treatment, blood and liver samples were collected for the analysis of biometal concentrations and relative gene expression of metal transporter and binding proteins. Exposure to repeated restraint stress was highly effective in causing hepatic redox imbalance. Stress was also shown to induce hepatic metal redistribution, while modulating the mRNA levels of key metal transporters. Overall, this study is the first to characterise the gene expression profile of metal homeostasis following stress and provide insight into the changes occurring prior to the onset of chronic stress conditions.

9.
Biochimie ; 180: 30-42, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33122103

ABSTRACT

Bidirectional communication between the neuroendocrine stress and immune systems permits classically anti-inflammatory glucocorticoids to exert pro-inflammatory effects in specific cells and tissues. Liver macrophages/Kupffer cells play a crucial role in initiating inflammatory cascades mediated by the release of pro-inflammatory cytokines following tissue injury. However, the effects of repeated acute psychological stress on hepatic inflammatory phenotype and macrophage activation state remains poorly understood. We have utilised a model of repeated acute stress in rodents to observe the changes in hepatic inflammatory phenotype, including anti-inflammatory vitamin D status, in addition to examining markers of classically and alternatively-activated macrophages. Male Wistar rats were subjected to control conditions or 6 h of restraint stress applied for 1 or 3 days (n = 8 per group) after which plasma concentrations of stress hormone, enzymes associated with liver damage, and vitamin D status were examined, in addition to hepatic expression of pro- and anti-inflammatory markers. Stress increased glucocorticoids and active vitamin D levels in addition to expression of glucocorticoid alpha/beta receptor, whilst changes in circulating hepatic enzymes indicated sustained liver damage. A pro-inflammatory response was observed in liver tissues following stress, and inducible nitric oxide synthase being observed within hepatic macrophage/Kupffer cells. Together, this suggests that stress preferentially induces a pro-inflammatory response in the liver.


Subject(s)
Hepatitis/metabolism , Hepatitis/physiopathology , Macrophage Activation/physiology , Stress, Psychological/blood , Stress, Psychological/physiopathology , Animals , Biomarkers , Cytokines/metabolism , Kupffer Cells/metabolism , Male , NF-kappa B/metabolism , Nitric Oxide Synthase Type II/metabolism , PPAR gamma/metabolism , Rats, Wistar , Receptors, Glucocorticoid/genetics , Receptors, Interleukin-8B/metabolism , Vitamin D/metabolism
10.
Antioxidants (Basel) ; 9(9)2020 Sep 11.
Article in English | MEDLINE | ID: mdl-32932938

ABSTRACT

Hepatic glutathione synthesis and antioxidant protection are critically important for efficient detoxification processes in response to metabolic challenges. However, this biosynthetic pathway, regulated by nuclear factor (erythroid-derived 2)-like 2 (Nrf2), previously demonstrated paradoxical repression following exposure to glucocorticoid stress hormones in cultured hepatic cells. Therefore, the present study used an in vivo model of sub-acute psychological stress to investigate the relationship between hepatic corticosteroid regulation and antioxidant systems. Male Wistar rats were kept under control conditions or subjected to six hours of restraint stress applied for 1 or 3 days (n = 8 per group) after which the liver was isolated for assays of oxidative/nitrosative status and expression of corticosteroid regulatory and Nrf2-antioxidant response element pathway members. A single stress exposure produced a significant increase in the expression of corticosterone reactivator, 11-beta-hydroxysteroid dehydrogenase 1 (11ß-Hsd1), while the 11ß-Hsd2 isozyme and corticosteroid-binding globulin were down-regulated following stress, indicative of an elevated availability of active corticosterone. Exposure to restraint significantly decreased hepatic concentrations of total cysteine thiols and the antioxidant reduced glutathione on Day 1 and increased 3-nitrotyrosinated and carbonylated proteins on Day 3, suggestive of oxidative/nitrosative stress in the liver following stress exposure. Conversely, there was a sustained down-regulation of Nrf2 mRNA and protein in addition to significant reductions in downstream glutamate-cysteine ligase catalytic subunit (Gclc), the rate-limiting enzyme in glutathione synthesis, on Day 1 and 3 of stress treatment. Interestingly, other antioxidant genes including superoxide dismutase 1 and 2, and glutathione peroxidase 4 were significantly up-regulated following an episode of restraint stress. In conclusion, the results of the present study indicate that increased expression of 11ß-Hsd1, indicative of elevated tissue glucocorticoid concentrations, may impair the Nrf2-dependent antioxidant response.

12.
Free Radic Biol Med ; 134: 468-483, 2019 04.
Article in English | MEDLINE | ID: mdl-30716433

ABSTRACT

Stress is a multimodal response involving the coordination of numerous body systems in order to maximize the chance of survival. However, long term activation of the stress response results in neuronal oxidative stress via reactive oxygen and nitrogen species generation, contributing to the development of depression. Stress-induced depression shares a high comorbidity with other neurological conditions including Alzheimer's disease (AD) and dementia, often appearing as one of the earliest observable symptoms in these diseases. Furthermore, stress and/or depression appear to exacerbate cognitive impairment in the context of AD associated with dysfunctional catecholaminergic signaling. Given there are a number of homologous pathways involved in the pathophysiology of depression and AD, this article will highlight the mechanisms by which stress-induced perturbations in oxidative stress, and particularly NO signaling, contribute to neurodegeneration.


Subject(s)
Alzheimer Disease/complications , Nervous System Diseases/etiology , Nitric Oxide/metabolism , Oxidative Stress , Animals , Humans , Nervous System Diseases/metabolism , Nervous System Diseases/pathology , Signal Transduction
13.
Free Radic Biol Med ; 130: 446-457, 2019 01.
Article in English | MEDLINE | ID: mdl-30445125

ABSTRACT

We have previously demonstrated that acute stress decreases neuronal nitric oxide synthase (NOS) expression in the hippocampus despite increased concentrations of nitric oxide which may indicate feedback inhibition of neuronal NOS expression via inducible NOS-derived nitric oxide. Moreover, the hippocampus undergoes an initial oxidative/nitrosative insult that is rapidly followed by upregulation of protective antioxidants, including the zinc-binding metallothioneins, in order to counter this and restore redox balance following acute stress exposure. In the present study, we have utilized indicators of oxidative/nitrosative stress, members of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway, antioxidant metallothioneins, and neuroinflammatory markers to observe the changes occurring in the hippocampus following short term repeated stress exposure. Male Wistar rats were subjected to control conditions or 6 h of restraint stress applied for 1, 2, or 3 days (n = 8 per group) after which the hippocampus was isolated for redox assays and relative gene expression. The hippocampus showed increased oxidative stress, transient dys-homeostasis of total zinc, and increased expression of the Nrf2 pathway members. Moreover, repeated stress increased nitrosative status, nitric oxide metabolites, and 3-nitrotyrosine, indicative of nitrosative stress in the hippocampus. However, levels of neuronal NOS decreased over all stress treatment groups, while increases were observed in inducible NOS and xanthine dehydrogenase. In addition to inducible NOS, mRNA expression of other inflammatory markers including interleukin-6 and interleukin-1ß also increased even in the presence of increased anti-inflammatory glucocorticoids. Together, these results demonstrate that despite increases in antioxidant expression, sub-acute stress causes an inflammatory phenotype in the hippocampus by inducing oxidative/nitrosative stress, zinc dys-homeostasis, and the accumulation of nitrotyrosinated proteins which is likely driven by increased inducible NOS signaling.


Subject(s)
Biomarkers/metabolism , Inflammation/genetics , Nitrosative Stress/genetics , Oxidative Stress/genetics , Animals , Antioxidants/metabolism , Gene Expression Regulation/genetics , Glucocorticoids/pharmacology , Hippocampus/metabolism , Humans , Inflammation/pathology , Interleukin-1beta/genetics , NF-E2-Related Factor 2/genetics , Nitric Oxide Synthase Type II/genetics , Oxidation-Reduction , RNA, Messenger/genetics , Rats , Rats, Wistar
14.
Int J Neuropsychopharmacol ; 21(8): 786-795, 2018 08 01.
Article in English | MEDLINE | ID: mdl-29579222

ABSTRACT

BACKGROUND: Long-term exposure to stress has been demonstrated to cause neuroinflammation through a sustained overproduction of free radicals, including nitric oxide, via an increased inducible nitric oxide synthase activity. We previously demonstrated that inducible nitric oxide synthase activity and mRNA are significantly upregulated in the rat hippocampus following just 4 hours of restraint stress. Similar to nitric oxide, endocannabinoids are synthesized on demand, with preclinical observations suggesting that cannabinoid receptor agonists and endocannabinoid enhancers inhibit nitrergic activity. Specifically, previous work has shown that enhancement of endocannabinoids via inhibition of fatty acid amide hydrolase with PF-3845 reduced inducible nitric oxide synthase-expressing microglia following traumatic brain injury. However, this describes cannabinoid modulation following physical injury, and therefore the present study aimed to examine the effects of PF-3845 in the modulation of nitrergic and inflammatory-related genes within the hippocampus after acute stress exposure. METHODS: Following vehicle or PF-3845 injections (5 mg/kg; i.p.), male Wistar rats were exposed to 0 (control), 60, 240, or 360 minutes of restraint stress after which plasma and dorsal hippocampus were isolated for further biochemical and gene expression analysis. RESULTS: The results demonstrate that pretreatment with PF-3845 rapidly ameliorates plasma corticosterone release at 60 minutes of stress. An increase in endocannabinoid signalling also induces an overall attenuation in inducible nitric oxide synthase, tumor necrosis factor-alpha convertase, interleukin-6, cyclooxygenase-2, peroxisome proliferator-activated receptor gamma mRNA, and the transactivation potential of nuclear factor kappa-light-chain-enhancer of activated B cells in the hippocampus. CONCLUSIONS: These results suggest that enhanced endocannabinoid levels in the dorsal hippocampus have an overall antinitrosative and antiinflammatory effect following acute stress exposure.


Subject(s)
Amidohydrolases/antagonists & inhibitors , Cytokines/metabolism , Enzyme Inhibitors/pharmacology , Hippocampus/drug effects , Inflammation Mediators/metabolism , Nitrosative Stress/drug effects , Piperidines/pharmacology , Pyridines/pharmacology , Stress, Psychological/drug therapy , Amidohydrolases/metabolism , Animals , Corticosterone/blood , Cytokines/genetics , Disease Models, Animal , Endocannabinoids/metabolism , Hippocampus/enzymology , Hippocampus/physiopathology , Male , Nitrates/metabolism , Nitric Oxide/metabolism , Nitrites/metabolism , Rats, Wistar , Restraint, Physical , Signal Transduction , Stress, Psychological/enzymology , Stress, Psychological/physiopathology , Time Factors , Tyrosine/analogs & derivatives , Tyrosine/metabolism
15.
Data Brief ; 21: 2627-2632, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30761344

ABSTRACT

This data article presents complementary results pertaining to the research article entitled "Sub-acute restraint stress progressively increases oxidative/nitrosative stress and inflammatory markers while transiently upregulating antioxidant gene expression in the rat hippocampus" (Chen et al., 2018). The present article provides additional gene expression data of selected neuroinflammatory markers and regulatory enzymes involved in oxidation-reduction reactions. Male Wistar rats aged 7-8 weeks were exposed to control, 1, 2, or 3 episodes of 6-h restraint stress in the light cycle after which the whole brain was quickly removed and the hippocampus excised for relative gene expression analysis. Specifically, mRNA levels of inflammatory regulators including allograft inflammatory factor 1, class II major histocompatibility complex, integrin alpha M, interferon gamma, and prostaglandin-endoperoxide synthase 2 were analyzed by real-time PCR. The gene expression of redox regulatory enzymes including glutathione peroxidase 1, glutathione peroxidase 4, superoxide dismutase 1, superoxide dismutase 2, myeloperoxidase, and NADPH oxidase subunit P47phox were also determined. These data provide useful insights in the molecular basis of inflammatory and redox regulation in the hippocampus following a short term to repeated psychological challenge in rats.

16.
Adv Physiol Educ ; 41(1): 154-162, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28235754

ABSTRACT

The ability to critically evaluate and use evidence from one's own work or from primary literature is invaluable to any researcher. These skills include the ability to identify strengths and weakness of primary literature, to gauge the impact of research findings on a field, to identify gaps in a field that require more research, and to contextualize findings within a field. This study developed a model to examine undergraduate science students' abilities to critically evaluate and use evidence through an analysis of laboratory reports from control and experimental groups in nonresearch-aligned and research-aligned inquiry-based laboratory classes, respectively, and contrasted these with published scientific research articles. The reports analyzed (n = 42) showed that students used evidence in a variety of ways, most often referring to literature indirectly, and least commonly highlighting limitations of literature. There were significant positive correlations between grade awarded and the use of references, evidence, and length, but there were no significant differences between control and experimental groups, so data were pooled. The use of evidence in scientific research articles (n = 7) was similar to student reports except that expert authors were more likely to refer to their own results and cite more references. Analysis showed that students, by the completion of the second year of their undergraduate degree, had expertise approaching that of published authors. These findings demonstrate that it is possible to provide valuable broad-scale undergraduate research experiences to all students in a cohort, giving them exposure to the methods and communication processes of research as well as an opportunity to hone their critical evaluation skills.


Subject(s)
Biomedical Research/education , Education, Professional/methods , Knowledge , Periodicals as Topic , Physiology/education , Students, Health Occupations/psychology , Thinking , Authorship , Communication , Curriculum , Educational Status , Female , Humans , Male , Young Adult
17.
Stress ; 20(1): 59-67, 2017 01.
Article in English | MEDLINE | ID: mdl-28027673

ABSTRACT

In the laboratory setting, typical endocrine and targeted behavioral tests are limited in their ability to provide a direct assessment of stress in animals housed in undisturbed conditions. We hypothesized that an automated phenotyping system would allow the detection of subtle stress-related behavioral changes well beyond the time-frames examined using conventional methods. In this study, we have utilized the TSE PhenoMaster system to continuously record basal behaviors and physiological parameters including activity, body weight, food intake and oxygen consumption in undisturbed and stressed C57Bl/6J male mice (n = 12/group), with a pharmacological intervention using the conventional anxiolytic, diazepam (5 mg kg-1 i.p.; n = 8/group). We observed significant 20-30% reductions in locomotor activity in the dark phase, with subtle reductions in light phase activity for up to 96 h following a single 2 h episode of restraint stress. A single administration of diazepam reduced plasma corticosterone concentrations by 30-35% during stress exposure when compared to mice treated with vehicle. This treatment did not result in significantly different locomotor activity compared to vehicle within the first 48 h following restraint stress. However, diazepam treatment facilitated restoration of locomotor activity at 72 and 96 h after restraint stress exposure in comparison to vehicle-treated mice. Hence, the use of an automated phenotyping system allows a real time assessment of basal behaviors and empirical metabolism following exposure to restraint stress and demonstrates major and subtle changes in activity persist for several days after stress exposure.


Subject(s)
Body Weight/physiology , Locomotion/physiology , Monitoring, Physiologic/methods , Animals , Anti-Anxiety Agents/pharmacology , Body Weight/drug effects , Corticosterone/blood , Diazepam/pharmacology , Eating/drug effects , Eating/physiology , Locomotion/drug effects , Male , Mice , Mice, Inbred C57BL , Oxygen Consumption/drug effects , Oxygen Consumption/physiology , Restraint, Physical/physiology , Stress, Physiological/drug effects , Stress, Physiological/physiology
18.
J Basic Clin Physiol Pharmacol ; 27(5): 515-21, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27180341

ABSTRACT

BACKGROUND: This study examined the efficacy of the combination antioxidant, Formula 42 (F42), on cellular stress indicators in animal and human models of stress-induced oxidative stress. METHODS: A sub-chronic psychological stress model in rodents was used to induce stress and oxidative stress indicators over a 10-day period during which animals received oral doses of F42 or water. Following treatment, body weight, plasma stress hormone corticosterone, and oxidative capacity were evaluated. In healthy human subjects, a randomized double-blind crossover study was used to examine the antioxidant effect of F42 or placebo in an exercise-induced oxidative stress model. Erythrocyte and plasma oxidative status was evaluated using the fluorescent activation of 2',7'-dichlorofluorescin (DCF) as an indicator. RESULTS: Oral administration of F42 reduced the corticosterone response to acute stress compared to vehicle but did not differ at the conclusion of the 10-day study. However, F42 administration did reduce stress-induced growth restriction and alleviate DCF activation in circulating erythrocytes by approximately 10% following 10 days of stress exposure. Oral administration of F42 also significantly reduced DCF activation by approximately 10% in healthy human subjects undergoing exercise-induced oxidative stress. CONCLUSIONS: Oral administration of F42 in rodents produces transient reductions in stress hormones and reduces stress indicators following sub-chronic psychological stress exposure. In humans, F42 acts as an early and potent antioxidant capable of scavenging free radicals within 30 min of ingestion.


Subject(s)
Antioxidants/pharmacology , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Viridiplantae/chemistry , Administration, Oral , Adolescent , Adult , Animals , Corticosterone/metabolism , Cross-Over Studies , Double-Blind Method , Erythrocytes/drug effects , Exercise/physiology , Female , Fluoresceins/metabolism , Humans , Male , Mice , Mice, Inbred BALB C , Young Adult
19.
Data Brief ; 6: 582-6, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26909371

ABSTRACT

This data article provides additional evidence on gene expression changes in the neuronal and inducible isoforms of nitric oxide synthase in the medial prefrontal cortex following acute stress. Male Wistar rats aged 6-8 weeks were exposed to control or restraint stress conditions for up to four hours in the dark cycle after which the brain was removed and the medial prefrontal cortex isolated by cryodissection. Following RNA extraction and cDNA synthesis, gene expression data were measured using quantitative real-time PCR. The mRNA levels of the neuronal and inducible nitric oxide synthase isoforms, and the inhibitory subunit of NF-κB, I kappa B alpha were determined using the ΔΔCT method relative to control animals. This data article presents complementary results related to the research article entitled 'Acute restraint stress induces specific changes in nitric oxide production and inflammatory markers in the rat hippocampus and striatum' [1].

20.
Psychoneuroendocrinology ; 67: 104-12, 2016 May.
Article in English | MEDLINE | ID: mdl-26881836

ABSTRACT

The stress-induced imbalance in reduction/oxidation (redox) state has been proposed to play a major role in the etiology of neurological disorders. However, the relationship between psychological stress, central redox state, and potential protective mechanisms within specific neural regions has not been well characterized. In this study, we have used an acute psychological stress to demonstrate the dynamic changes that occur in the redox system of hippocampal and striatal tissue. Outbred male Wistar rats were subject to 0 (control), 60, 120, or 240min of acute restraint stress and the hippocampus and striatum were cryodissected for redox assays and relative gene expression. Restraint stress significantly elevated oxidative status and lipid peroxidation, while decreasing glutathione ratios overall indicative of oxidative stress in both neural regions. These biochemical changes were prevented by prior administration of the glucocorticoid receptor antagonist, RU-486. The hippocampus also demonstrated increased glutathione peroxidase 1 and 4 antioxidant expression which was not observed in the striatum, while both regions displayed robust upregulation of the antioxidant, metallothionein 1a. This was observed with concurrent upregulation of 11ß-hydroxysteroid dehydrogenase 1, a local reactivator of corticosterone, in addition to decreased expression of the cytosolic regulatory subunit of superoxide-producing enzyme, NADPH-oxidase. Together, this study demonstrates distinctive regional redox profiles following acute stress exposure, in addition to identifying differential capabilities in managing oxidative challenges via altered antioxidant gene expression in the hippocampus and striatum.


Subject(s)
Corpus Striatum/metabolism , Gene Expression/drug effects , Hippocampus/metabolism , Oxidation-Reduction , Stress, Psychological/metabolism , 11-beta-Hydroxysteroid Dehydrogenases/biosynthesis , Animals , Corpus Striatum/drug effects , Corticosterone/blood , Glutathione/metabolism , Glutathione Peroxidase/biosynthesis , Hippocampus/drug effects , Lipid Peroxidation , Male , Metallothionein/biosynthesis , Mifepristone/pharmacology , NADPH Oxidases/biosynthesis , NF-E2 Transcription Factor/biosynthesis , Phospholipid Hydroperoxide Glutathione Peroxidase , Rats , Restraint, Physical , Stress, Psychological/blood , Glutathione Peroxidase GPX1
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