Use of induced pluripotent stem cell derived neurons engineered to express BDNF for modulation of stressor related pathology

Combined cell and gene-based therapeutic strategies offer potential in the treatment of neurodegenerative and psychiatric conditions that have been associated with structural brain disturbances. In the present investigation, we used a novel virus-free re-programming method to generate induced pluripotent stem cells (iPSCs), and then subsequently transformed these cells into neural cells which over-expressed brain derived neurotrophic factor (BDNF). Importantly, the infusion of iPSC derived neural cells (as a cell replacement and gene delivery tool) and BDNF (as a protective factor) influenced neuronal outcomes Specifically, intracerebroventricular transplantation of iPSC-derived neural progenitors that over-expressed BDNF reversed the impact of immune (lipopolysaccharide) and chronic stressor challenges upon subventricular zone adult neurogenesis and the iPSC-derived neural progenitor cells alone blunted the stressor induced corticosterone response. Moreover, our findings also indicate that mature dopamine producing neurons can also be generated using iPSC procedures and these cells appeared to be viable when infused in vivo. Taken together, these data could have important implications for using gene-plus-cell replacement methods to modulate stressor related pathology

Cytomegalovirus is associated with depression and anxiety in older adults

Infection with cytomegalovirus (CMV), a β-herpesvirus, is common within the population. Although asymptomatic, infection is associated with increased serum concentrations of cytokines such as TNFα and IL-6, which are also related to mood and wellbeing. The present study examined whether infection with CMV was associated with mood in a community-based sample of olderadults. Blood samples and scores on the General Health Questionnaire were available for 137 participants. Serum was analysed for the presence of CMV-specific IgG and the antibody titre was used as an indirect measure of viral load. The majority of the participants (66%) were CMV-seropositive and seropositive status was not associated with psychological morbidity. However, within the CMV-positive group, individuals with higher CMV-specific antibody titres were more likely to be depressed, anxious, and suffer more overall psychological morbidity. This association could be mediated by the impact of affect-moderating cytokines secreted through the CMV-specific immune response.\ud \u

An efficient chronic unpredictable stress protocol to induce stress-relatec responses in C57BL/6 mice

Exposure to chronic stress can have broad effects on health ranging from increased predisposition for neuropsychiatric disorders to deregulation of immune responses. The chronic unpredictable stress (CUS) protocol has been widely used to study the impact of stress exposure in several animal models and consists in the random, intermittent, and unpredictable exposure to a variety of stressors during several weeks. CUS has consistently been shown to induce behavioral and immunological alterations typical of the chronic stress-response. Unfortunately C57BL/6 mice, one of the most widely used mouse strains, due to the great variety of genetically modified lines, seem to be resistant to the commonly used 4-week-long CUS protocol. The definition of an alternative CUS protocol allowing the use of C57BL/6 mice in chronic stress experiments is a need. Here, we show that by extending the CUS protocol to 8?weeks is possible to induce a chronic stress-response in C57BL/6 mice, as revealed by abrogated body weight gain, increased adrenals weight, and an overactive hypothalamic-pituitary-adrenal axis with increased levels of serum corticosterone. Moreover, we also observed stress-associated behavioral alterations, including the potentiation of anxious-like and depressive-like behaviors and a reduction of exploratory behavior, as well as subtle stress-related changes in the cell population of the thymus and of the spleen. The present protocol for C57BL/6 mice consistently triggers the spectrum of CUS-induced changes observed in rats and, thus, will be highly useful to researchers that need to use this particular mouse strain as an animal model of neuropsychiatric disorders and/or immune deregulation related to CUS.(undefined

Ablation of LMO4 in glutamatergic neurons impairs leptin control of fat metabolism

The LIM domain only 4 (LMO4) protein is expressed in the hypothalamus, but its function there is not known. Using mice with LMO4 ablated in postnatal glutamatergic neurons, including most neurons of the paraventricular (PVN) and ventromedial (VMH) hypothalamic nuclei where LMO4 is expressed, we asked whether LMO4 is required for metabolic homeostasis. LMO4 mutant mice exhibited early onset adiposity. These mice had reduced energy expenditure and impaired thermogenesis together with reduced sympathetic outflow to adipose tissues. The peptide hormone leptin, produced from adipocytes,activates Jak/Stat3 signaling at the hypothalamus to control food intake, energy expenditure, and fat metabolism. Intracerebroventricular infusion of leptin suppressed feeding similarly in LMO4 mutant and control mice.However, leptin-induced fat loss was impaired and activation of Stat3 in the VMH was blunted in these mice. Thus, our study identifies LMO4 as a novel modulator of leptin function in selective hypothalamic nuclei to regulate fat metabolism

Are Large Physiological Reactions to Acute Psychological Stress Always Bad for Health?

How we react physiologically to stress has long been considered to have implications for our health. There is now persuasive evidence that individuals who show large cardiovascular reactions to stress are at increased risk of developing cardiovascular disease, particularly hypertension. By implication, low reactivity is protective or benign. However, there is recent evidence that low reactivity may predict elevated risk for a range of adverse health outcomes, such as depression, obesity, poor self-reported health, and compromised immunity. In addition, low cortisol and cardiovascular reactivity may be a characteristic of individuals with addictions to tobacco and alcohol, as well as those at risk of addiction and those who relapse from abstinence. Our ideas about reactivity may have to be revised in the light of such findings

A review and conceptual re-examination of mental toughness: implications for future researchers

This paper provides a review of mental toughness research and examines the major conceptual concerns that are evident in current mental toughness literature. Despite more rigorous scientific approaches to the study of mental toughness, a number of limitations are apparent: these include the assumption that elite or super elite performers are mentally tough (failure to provide objective measures), focusing research solely on elite or super elite performers, appearing to conceptualise mental toughness in absolute rather than relative terms, and ignoring contextual differences. Comparisons are made with research developments in the related concept of hardiness. It is argued that more innovative approaches to research are required to further develop knowledge. This should include more experimental studies, longitudinal research, psychophysiological approaches, and testing the influence of mental toughness in contexts outside sport performance. Further efforts to understand how mental toughness develops are encouraged. With recent advances in instruments to measure mental toughness, further quantitative research is deemed appropriate. The efficacy of proposed methods of enhancing mental toughness such as environmental manipulations, and mental skills training approaches need to be evaluated if the gap between theoretical research and practice is to be bridged

Bidirectional Psychoneuroimmune Interactions in the Early Postpartum Period Influence Risk of Postpartum Depression

More than 500,000 U.S. women develop postpartum depression (PPD) annually. Although psychosocial risks are known, the underlying biology remains unclear. Dysregulation of the immune inflammatory response and the hypothalamic–pituitary–adrenal (HPA) axis are associated with depression in other populations. While significant research on the contribution of these systems to the development of PPD has been conducted, results have been inconclusive. This is partly because few studies have focused on whether disruption in the bidirectional and dynamic interaction between the inflammatory response and the HPA axis together influence PPD. In this study, we tested the hypothesis that disruption in the inflammatory-HPA axis bidirectional relationship would increase the risk of PPD. Plasma pro- and anti-inflammatory cytokines were measured in women during the 3rd trimester of pregnancy and on Days 7 and 14, and Months 1, 2, 3, and 6 after childbirth. Saliva was collected 5 times the day preceding blood draws for determination of cortisol area under the curve (AUC) and depressive symptoms were measured using the Edinburgh Postpartum Depression Survey (EPDS). Of the 152 women who completed the EPDS, 18% were depressed according to EDPS criteria within the 6 months postpartum. Cortisol AUC was higher in symptomatic women on Day 14 (p = .017). To consider the combined effects of cytokines and cortisol on predicting symptoms of PPD, a multiple logistic regression model was developed that included predictors identified in bivariate analyses to have an effect on depressive symptoms. Results indicated that family history of depression, day 14 cortisol AUC, and the day 14 IL8/IL10 ratio were significant predictors of PPD symptoms. One unit increase each in the IL8/IL10 ratio and cortisol AUC resulted in 1.50 (p = 0.06) and 2.16 (p = 0.02) fold increases respectively in the development of PPD. Overall, this model correctly classified 84.2% of individuals in their respective groups. Findings suggest that variability in the complex interaction between the inflammatory response and the HPA axis influence the risk of PPD

Cytokine responses to exercise and activity in patients with chronic fatigue syndrome: Case control study

Chronic fatigue syndrome (CFS) is characterized by fatigue after exertion. A systematic review suggested that transforming growth factor beta (TGF-β) concentrations are often elevated in cases of CFS when compared to healthy controls. This study attempted to replicate this finding, and investigate whether post-exertional symptoms were associated with altered cytokine protein concentrations and their RNA in CFS patients. Twenty-four patients fulfilling Centers for Disease Control criteria for CFS, but with no comorbid psychiatric disorders, were recruited from two CFS clinics in London, UK. Twenty-one healthy, sedentary controls were matched by gender, age, and other variables. Circulating proteins and RNA were measured for TGF-β, TNF, IL-8, IL-6 and IL-1β. We measured six further cytokine protein concentrations (IL-2, IL-4, IL-5, IL-10, IL-12p70, and IFN-γ). Measures were taken at rest, and before and after both commuting and aerobic exercise. CFS cases had higher TGF-β protein levels compared to controls at rest (median (quartiles) = 43.9 (19.2, 61.8) versus 18.9 (16.1, 30.0) ng/ml) (p = 0.003), and consistently so over a nine-day period. However, this was a spurious finding due to variation between different assay batches. There were no differences between groups in changes to TGF-β protein concentrations after either commuting or exercise. All other cytokine protein and RNA levels were similar between cases and controls. Post-exertional symptoms and perceived effort were not associated with any increased cytokines. We were unable to replicate previously found elevations in circulating cytokine concentrations, suggesting that elevated circulating cytokines are not important in the pathophysiology of CFS