Brain tissue haemoglobin expression in saline-perfused vs non-perfused rodents.

Haemoglobin beta (Hbb) and delta-aminolevulinate synthase 2 (Alas2) messenger RNA (mRNA) is mainly found in immature red blood cells, reticulocytes, and not in mature erythrocytes. However, these are also expressed in other tissues such as brain cells, mostly neurons. Therefore, exact quantification of neural tissue homogenates may be confounded by remaining blood in the brain vasculature that may give falsely high values of Hbb/Alas2 expression. To investigate and compare the contribution of local Hbb/Alas2 expression, we investigated mRNA expression locally in the hippocampus and prefrontal cortex, in post-sacrifice saline-perfused and non-perfused mice and rats. Although there was a higher level of Hbb/Alas2 transcripts in the non-perfused animals, there was a significant mRNA expression in perfused brains that could at most partially be explained by remaining blood. Finally, we suggest that saline-perfusion should be recommended for quantification of brain Hbb/Alas2 transcripts in homogenates.

Effects of exercise on symptoms of anxiety in primary care patients: A randomized controlled trial.

BACKGROUND: There is a need for high-quality research regarding exercise interventions for persons with anxiety disorders. We investigate whether a 12-week exercise intervention, with different intensities, could reduce anxiety symptoms in patients with anxiety disorders. METHODS: 286 patients were recruited from primary care in Sweden. Severity of symptoms was self-assessed using the Beck Anxiety Inventory (BAI) and the Montgomery Åsberg Depression Rating Scale (MADRS-S). Participants were randomly assigned to one of two group exercise programs with cardiorespiratory and resistance training and one control/standard treatment non-exercise group, with 1:1:1 allocation. RESULTS: Patients in both exercise groups showed larger improvements in both anxiety and depressive symptoms compared to the control group. No differences in effect sizes were found between the two groups. To study a clinically relevant improvement, BAI and MADRS-S were dichotomized with the mean change in the control group as reference. In adjusted models the odds ratio for improved symptoms of anxiety after low-intensity training was 3.62 (CI 1.34-9.76) and after moderate/high intensity 4.88 (CI 1.66-14.39), for depressive symptoms 4.96 (CI 1.81-13.6) and 4.36 (CI 1.57-12.08) respectively. There was a significant intensity trend for improvement in anxiety symptoms. LIMITATIONS: The use of self-rating measures which bears the risk of an under- or overestimation of symptoms. CONCLUSIONS: A 12-week group exercise program proved effective for patients with anxiety syndromes in primary care. These findings strengthen the view of physical exercise as an effective treatment and could be more frequently made available in clinical practice for persons with anxiety issues.

Anxiety severity and cognitive function in primary care patients with anxiety disorder: a cross-sectional study.

BACKGROUND: Deficits in cognitive performance are reported in patients with anxiety disorders, but research is limited and inconsistent. We aimed to investigate cross-sectional associations between cognitive function, with focus on executive function, and anxiety severity in primary care patients diagnosed with anxiety disorders. METHODS: 189 Swedish patients aged 18-65 years (31% men) with anxiety disorders diagnosed according to Mini International Neuropsychiatric Interview were included. Severity of anxiety was assessed using Beck Anxiety Inventory self-assessment scale. Digit span, block design and matrix reasoning tests from the Wechsler Adult Intelligence Scale IV, and the design fluency test from the Delis-Kaplan Executive Function System were used. Multivariable linear regression models were applied to investigate the relationship of anxiety severity and cognitive functioning. Comparisons were also performed to a normed non-clinical population, using the Wilcoxon signed rank test. RESULTS: More severe anxiety was associated with lower digit span test scores (R2 = 0.109, B = -0.040, p = 0.018), but not with block design, matrix reasoning or design fluency tests scores, after adjustment for comorbid major depression in a multivariable model. When compared to a normed population, patients with anxiety performed significantly lower on the block design, digit span forward, digit span sequencing and matrix reasoning tests. CONCLUSIONS: Severity of anxiety among patients with anxiety disorder was associated with executive functions related to working memory, independently of comorbid major depression, but not with lower fluid intelligence. A further understanding of the executive behavioral control in patients with anxiety could allow for more tailored treatment strategies including medication, therapy and interventions targeted to improve specific cognitive domains.

Dietary Fiber and the Hippocampal Neurogenic Niche in a Model of Pelvic Radiotherapy.

We sought to determine whether radiation to the colorectum had an impact on parameters of hippocampal neurogenesis and, if so, whether it could be modulated by a fiber-rich diet. Male C57BL/6J mice were fed a diet containing bioprocessed oat bran or a fiber-free diet, starting two weeks before colorectal irradiation with 4 fractions of 8 Gray or sham-irradiation. Diets were then continued for 1, 6 or 18 weeks, whereafter parameters of hippocampal neurogenesis were analyzed and correlated to serum cytokine levels. No statistically significant changes in neuronal markers or cell proliferation were found at one week post-irradiation. Six weeks post-irradiation there was a decreased cell proliferation in the subgranular zone that appeared slightly more pronounced in irradiated animals on a fiber-free diet and increased numbers of immature neurons per mm2 dentate gyrus in the irradiated mice, with a statistically significant increase in mice on a fiber-rich diet. Microglial abundancy was similar between all groups. 18 weeks post-irradiation, a fiber-free diet had reduced the number of immature neurons, whereas irradiation resulted in an increase. Despite this, the population of mature neurons was stable. Analysis of serum cytokines revealed a negative correlation between MIP1-α and the number of immature neurons one week after irradiation, regardless of diet. Our findings show that pelvic radiotherapy has the potential to cause a long-lasting impact on hippocampal neurogenesis, and dietary interventions may modulate this impact. More in-depth studies on the relationship between irradiation-induced intestinal injury and brain health are warranted.

Exhaustion disorder and altered brain activity in frontal cortex detected with fNIRS.

Patients with stress-related Exhaustion Disorder (ED) have problems with memory and executive function. These problems have been associated with deviant activity in prefrontal cortex (PFC). We investigated cognitive performance and functional activity in the PFC during prolonged mental activity in patients with ED (n = 20, 16 women) with a mean duration since diagnosis of 46 ± 23 months in comparison to healthy individuals (n = 20, 12 women). A block of six neuropsychological tests was performed in a sequence that was repeated once. The brain imaging technique, functional near infrared spectroscopy (fNIRS) was used for all tests. There were no differences between the groups in terms of changes over time, i.e. difference between first and second test block. In the Stroop-Simon test, the controls showedhigher functional activity in the frontal cortex. In the left ventrolateral PFC, we observed an increased activity in controls in the incongruent compared to the congruent trials, whereas no changes were detected in the ED patient group. During processing speed tasks, only ED patients showed higher functional activity in right dorsolateral PFC. The ED patients reported lower subjective energy level and they also performed less well on a mental control task compared to healthy individuals. In conclusion, ED patients showed altered functional activity compared to controls, indicating that ED patients process information differently in the prefrontal cortex, but the functional activity did not change during the 2½ hr procedure, as revealed by the test-retest design. Lay summary In this paper we show that patient with exhaustion disorder have a reduced functional activity in the prefrontal cortex. This functional activity was not affected by 2.5 hours mental activity.

Cranial irradiation at early postnatal age impairs stroke-induced neural stem/progenitor cell response in the adult brain.

Cranial irradiation (IR) is commonly used to treat primary brain tumors and metastatic diseases. However, cranial IR-treated patients often develop vascular abnormalities later in life that increase their risk for cerebral ischemia. Studies in rodents have demonstrated that IR impairs maintenance of the neural stem/precursor cell (NSPC) pool and depletes neurogenesis. We and others have previously shown that stroke triggers NSPC proliferation in the subventricular zone and migration towards the stroke-injured neocortex. Whether this response is sustained in the irradiated brain remains unknown. Here, we demonstrate that cranial IR in mice at an early postnatal age significantly reduced the number to neuronal progenitors responding to cortical stroke in adults. This was accompanied by a reduced number of microglia/macrophages in the peri-infarct cortex; however, the astrocytic response was not altered. Our findings indicate that IR impairs the endogenous repair capacity in the brain in response to stroke, hence pointing to another side effect of cranial radiotherapy which requires further attention.

Enriched, Task-Specific Therapy in the Chronic Phase After Stroke: An Exploratory Study.

BACKGROUND AND PURPOSE: There is a need to translate promising basic research about environmental enrichment to clinical stroke settings. The aim of this study was to assess the effectiveness of enriched, task-specific therapy in individuals with chronic stroke. METHODS: This is an exploratory study with a within-subject, repeated-measures design. The intervention was preceded by a baseline period to determine the stability of the outcome measures. Forty-one participants were enrolled at a mean of 36 months poststroke. The 3-week intervention combined physical therapy with social and cognitive stimulation inherent to environmental enrichment. The primary outcome was motor recovery measured by Modified Motor Assessment Scale (M-MAS). Secondary outcomes included balance, walking, distance walked in 6 minutes, grip strength, dexterity, and multiple dimensions of health. Assessments were made at baseline, immediately before and after the intervention, and at 3 and 6 months. RESULTS: The baseline measures were stable. The 39 participants (95%) who completed the intervention had increases of 2.3 points in the M-MAS UAS and 5 points on the Berg Balance Scale (both P < 0.001; SRM >0.90), an improvement of comfortable and fast gait speed of 0.13 and 0.23 m/s, respectively. (P < 0.001; SRM = 0.88), an increased distance walked over 6 minutes (24.2 m; P < 0.001; SRM = 0.64), and significant improvements in multiple dimensions of health. The improvements were sustained at 6 months. DISCUSSION AND CONCLUSIONS: Enriched, task-specific therapy may provide durable benefits across a wide spectrum of motor deficits and impairments after stroke. Although the results must be interpreted cautiously, the findings have implications for enriching strategies in stroke rehabilitation.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A304).

Growth Hormone and Neuronal Hemoglobin in the Brain-Roles in Neuroprotection and Neurodegenerative Diseases.

In recent years, evidence for hemoglobin (Hb) synthesis in both animal and human brains has been accumulating. While circulating Hb originating from cerebral hemorrhage or other conditions is toxic, there is also substantial production of neuronal Hb, which is influenced by conditions such as ischemia and regulated by growth hormone (GH), insulin-like growth factor-I (IGF-I), and other growth factors. In this review, we discuss the possible functions of circulating and brain Hb, mainly the neuronal form, with respect to the neuroprotective activities of GH and IGF-I against ischemia and neurodegenerative diseases. The molecular pathways that link Hb to the GH/IGF-I system are also reviewed, although the limited number of reports on this topic suggests a need for further studies. In summary, GH and/or IGF-I appear to be significant determinants of systemic and local brain Hb concentrations through mediating responses to oxygen and metabolic demand, as part of the neuroprotective effects exerted by GH and IGF-I. The nature and quantity of the latter deserve further exploration in specific experiments.

Late-adolescent risk factors for suicide and self-harm in middle-aged men: explorative prospective population-based study.

BACKGROUND: Recent reports show alarmingly high rates of suicide in middle-aged men, yet there are few long-term prospective studies that focus on suicidal behaviour in men in this age group. AIMS: To prospectively explore associations of potential risk factors at age 18 with suicide and self-harm in middle-aged men. METHOD: A population-based Swedish longitudinal cohort study of male conscripts with no history of self-harm at enlistment in 1968-1989 (n = 987 583). Conscription examinations included measures of cognitive performance, stress resilience, psychiatric diagnoses, body mass index (BMI), cardiovascular fitness and muscle strength. Suicides and self-harm at age 45-65 years were identified in the National Hospital Register and Swedish Cause of Death Register. Risks were calculated using Cox proportional hazards models. RESULTS: Low stress resilience (cause-specific hazard ratio CHR = 2.31, 95% CI 1.95-2.74), low cognitive ability (CHR = 2.01, 95% CI 1.71-2.37) as well as psychiatric disorders and low cardiovascular fitness in late adolescence were associated with increased risk for suicide in middle-aged men. Similar risk estimates were obtained for self-harm. In addition, high and low BMI as well as low muscle strength were associated with increased risk of self-harm. Associations also remained significant after exclusion of men with self-harm before age 45. CONCLUSIONS: This prospective study provides life-course perspective support that psychological and physical characteristics in late adolescence may have long-lasting consequences for suicidal behaviour in middle-aged men, a very large population at heightened risk of suicide.

Effects of exercise on symptoms of anxiety, cognitive ability and sick leave in patients with anxiety disorders in primary care: study protocol for PHYSBI, a randomized controlled trial.

BACKGROUND: Anxiety disorders are common and associated with reduced quality of life, impaired physical and mental health and an increased economic burden for society. While evidence exists for the effectiveness of exercise treatment for depression, there is a need for high-quality randomized clinical trials (RCT) with a focus on anxiety disorders. Further research is also warranted regarding outcomes of cognitive function, other health-related variables, dose-response effects, work ability and potential mechanisms. METHOD/DESIGN: Using a parallel, RCT design with three assessment points (baseline, post-intervention and one-year follow-up), we aim to assess the effect of a 12-week exercise intervention in primary care patients with anxiety disorders (n = 180), diagnosed using the Mini International Neuropsychiatric Interview (M.I.N.I; Swedish version 6.0.0d DSM-IV). Participants are randomly assigned to three physical exercise groups: one low-intensity training group, one moderate- to high intensity training group and one control non-exercise group. Assessments include measures of anxiety symptoms, cognitive function, physical health variables such as cardiovascular fitness, sick-leave and levels of hormones/cytokines in blood samples. DISCUSSION: Findings from this study will provide novel insights regarding the effects of exercise treatment on not only anxiety symptoms but also other outcomes including mental and physical health, cognitive function, dose-response effects, work ability/sick leave and on biomarkers that may help explain underlying mechanisms. TRIAL REGISTRATION: The trial was registered at ClinicalTrial.gov NCT03247270 August 8, 2017.

Adult Hippocampal Neurogenesis: A Coming-of-Age Story.

What has become standard textbook knowledge over the last decade was a hotly debated matter a decade earlier: the proposition that new neurons are generated in the adult mammalian CNS. The early discovery by Altman and colleagues in the 1960s was vulnerable to criticism due to the lack of technical strategies for unequivocal demonstration, quantification, and physiological analysis of newly generated neurons in adult brain tissue. After several technological advancements had been made in the field, we published a paper in 1996 describing the generation of new neurons in the adult rat brain and the decline of hippocampal neurogenesis during aging. The paper coincided with the publication of several other studies that together established neurogenesis as a cellular mechanism in the adult mammalian brain. In this Progressions article, which is by no means a comprehensive review, we recount our personal view of the initial setting that led to our study and we discuss some of its implications and developments that followed. We also address questions that remain regarding the regulation and function of neurogenesis in the adult mammalian brain, in particular the existence of neurogenesis in the adult human brain.

Altered levels of circulating insulin-like growth factor I (IGF-I) following ischemic stroke are associated with outcome - a prospective observational study.

BACKGROUND: Insulin-like growth factor I (IGF-I) has neuroprotective effects in experimental ischemic stroke (IS). However, in patients who have suffered IS, various associations between the levels of serum IGF-I (s-IGF-I) and clinical outcome have been reported, probably reflecting differences in sampling time-points and follow-up periods. Since changes in the levels of post-stroke s-IGF-I have not been extensively explored, we investigated whether decreases in the levels of s-IGF-I between the acute time-point (median, 4 days) and 3 months (ΔIGF-I, further transformed into ΔIGF-I-quintiles, ΔIGF-I-q) are associated with IS severity and outcome. METHODS: In the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS) conducted in Gothenburg, Sweden, patients with IS who had s-IGF-I measurements available were included (N = 354; 65% males; mean age, 55 years). Baseline stroke severity was evaluated using the National Institutes of Health Stroke Scale (NIHSS) and converted into NIHSS-quintiles (NIHSS-q). Outcomes were assessed using the modified Rankin Scale (mRS) at 3 months and 2 years. RESULTS: In general, the levels of s-IGF-I decreased (positive ΔIGF-I), except for those patients with the most severe NIHSS-q. After correction for sex and age, the 3rd ΔIGF-I-q showed the strongest association to mRS 0-2 [Odds Ratio (OR) 5.11, 95% confidence interval (CI) 2.18-11.9], and after 2 years, the 5th ΔIGF-I-q (OR 3.63, 95% CI 1.40-9.38) showed the strongest association to mRS 0-2. The associations remained significant after multivariate correction for diabetes, smoking, hypertension, and hyperlipidemia after 3 months, but were not significant (p = 0.057) after 2 years. The 3-month associations withstood additional correction for baseline stroke severity (p = 0.035), whereas the 2-year associations were further attenuated (p = 0.31). CONCLUSIONS: Changes in the levels of s-IGF-I are associated primarily with temporally near 3-month outcomes, while associations with long-term 2-year outcomes are weakened and attenuated by other factors. The significance of the change in post-stroke s-IGF-I is compatible with a positive role for IGF-I in IS recovery. However, the exact mechanisms are unknown and probably reflects combinations of multiple peripheral and central actions.

Human Adult Neurogenesis: Evidence and Remaining Questions.

Renewed discussion about whether or not adult neurogenesis exists in the human hippocampus, and the nature and strength of the supporting evidence, has been reignited by two prominently published reports with opposite conclusions. Here, we summarize the state of the field and argue that there is currently no reason to abandon the idea that adult-generated neurons make important functional contributions to neural plasticity and cognition across the human lifespan.

In vivo migration of endogenous brain progenitor cells guided by an injectable peptide amphiphile biomaterial.

Biomaterials hold great promise in helping the adult brain regenerate and rebuild after trauma. Peptide amphiphiles (PAs) are highly versatile biomaterials, gelling and forming macromolecular structures when exposed to physiological levels of electrolytes. We are here reporting on the first ever in vivo use of self-assembling PA carrying a Tenascin-C signal (E2 Ten-C PA) for the redirection of endogenous neuroblasts in the rodent brain. The PA forms highly aligned nanofibers, displaying the migratory sequence of Tenascin-C glycoprotein as epitope. In this in vivo work, we have formed in situ a gel of aligned PA nanofibers presenting a migratory Tenascin-C signal sequence in the ventral horn of the rostral migratory stream, creating a track reaching the neocortex. Seven days posttransplant, doublecortin positive cells were observed migrating inside and alongside the injected biomaterial, reaching the cortex. We observed a 24-fold increase in number of redirected neuroblasts for the E2 Ten-C PA-injected animals compared to control. We also found injecting the E2 Ten-C PA to cause minimal neuroinflammatory response. Analysing GFAP+ astrocytes and Iba1+ microglia activation, the PA does not elicit a stronger neuroinflammatory response than would be expected from a small needle stab wound. Redirecting endogenous neuroblasts and increasing the number of cells reaching a site of injury using PAs may open up new avenues for utilizing the pool of neuroblasts and neural stem cells within the adult brain for regenerating damaged brain tissue and replacing neurons lost to injury.

Exercise in Adulthood after Irradiation of the Juvenile Brain Ameliorates Long-Term Depletion of Oligodendroglial Cells.

Cranial radiation severely affects brain health and function, including glial cell production and myelination. Recent studies indicate that voluntary exercise has beneficial effects on oligodendrogenesis and myelination. Here, we hypothesized that voluntary running would increase oligodendrocyte numbers in the corpus callosum after irradiation of the juvenile mouse brain. The brains of C57Bl/6J male mice were 6 Gy irradiated on postnatal day 9 during the main gliogenic developmental phase, resulting in a loss of oligodendrocyte precursor cells. Upon adulthood, the mice were injected with bromodeoxyuridine and allowed to exercise on a running wheel for four weeks. Cell proliferation and survival, Ascl1+ oligodendrocyte precursor and Olig2+ oligodendrocyte cell numbers as well as CC1+ mature oligodendrocytes were quantified using immunohistology. Radiation induced a reduction in the number of Olig2+ oligodendrocytes by nearly 50% without affecting production or survival of new Olig2+ cells. Ascl1+ cells earlier in the oligodendroglial cell lineage were also profoundly affected, with numbers reduced by half. By three weeks of age, Olig2+ cell numbers had not recovered, and this was paralleled by a volumetric loss in the corpus callosum. The deficiency of Olig2+ oligodendrocytes persisted into adulthood. Additionally, the depletion of Ascl1+ progenitor cells was irreversible, and was even more pronounced at 12 weeks postirradiation compared to day 2 postirradiation. Furthermore, the overall number of CC1+ mature oligodendrocytes decreased by 28%. The depletion of Olig2+ cells in irradiated animals was reversed by 4 weeks of voluntary exercise. Moreover, voluntary exercise also increased the number of Ascl1+ progenitor cells in irradiated animals. Taken together, these results demonstrate that exercise in adulthood significantly ameliorates the profound and long-lasting effects of moderate exposure to immature oligodendrocytes during postnatal development.

A tenascin-C mimetic peptide amphiphile nanofiber gel promotes neurite outgrowth and cell migration of neurosphere-derived cells.

UNLABELLED: Biomimetic materials that display natural bioactive signals derived from extracellular matrix molecules like laminin and fibronectin hold promise for promoting regeneration of the nervous system. In this work, we investigated a biomimetic peptide amphiphile (PA) presenting a peptide derived from the extracellular glycoprotein tenascin-C, known to promote neurite outgrowth through interaction with ß1 integrin. The tenascin-C mimetic PA (TN-C PA) was found to self-assemble into supramolecular nanofibers and was incorporated through co-assembly into PA gels formed by highly aligned nanofibers. TN-C PA content in these gels increased the length and number of neurites produced from neurons differentiated from encapsulated P19 cells. Furthermore, gels containing TN-C PA were found to increase migration of cells out of neurospheres cultured on gel coatings. These bioactive gels could serve as artificial matrix therapies in regions of neuronal loss to guide neural stem cells and promote through biochemical cues neurite extension after differentiation. One example of an important target would be their use as biomaterial therapies in spinal cord injury. STATEMENT OF SIGNIFICANCE: Tenascin-C is an important extracellular matrix molecule in the nervous system and has been shown to play a role in regenerating the spinal cord after injury and guiding neural progenitor cells during brain development, however, minimal research has been reported exploring the use of biomimetic biomaterials of tenascin-C. In this work, we describe a selfassembling biomaterial system in which peptide amphiphiles present a peptide derived from tenascin-C that promotes neurite outgrowth. Encapsulation of neurons in hydrogels of aligned nanofibers formed by tenascin-C-mimetic peptide amphiphiles resulted in enhanced neurite outgrowth. Additionally, these peptide amphiphiles promoted migration of neural progenitor cells cultured on nanofiber coatings. Tenascin-C biomimetic biomaterials such as the one described here have significant potential in neuroregenerative medicine.

Detection and Phenotypic Characterization of Adult Neurogenesis.

Studies of adult neurogenesis have greatly expanded in the last decade, largely as a result of improved tools for detecting and quantifying neurogenesis. In this review, we summarize and critically evaluate detection methods for neurogenesis in mammalian and human brain tissue. Besides thymidine analog labeling, cell-cycle markers are discussed, as well as cell stage and lineage commitment markers. Use of these histological tools is critically evaluated in terms of their strengths and limitations, as well as possible artifacts. Finally, we discuss the method of radiocarbon dating for determining cell and tissue turnover in humans.

Nonpsychotic Mental Disorders in Teenage Males and Risk of Early Stroke: A Population-Based Study.

BACKGROUND AND PURPOSE: Although the incidence of stroke is on the decline worldwide, this is not the case for early stroke. We aimed to determine whether nonpsychotic mental disorder at the age of 18 years is a risk factor for early stroke, and if adolescent cardiovascular fitness and intelligence quotient might attenuate the risk. METHOD: Population-based Swedish cohort study of conscripts (n=1 163 845) who enlisted during 1968 to 2005. At conscription, 45 064 males were diagnosed with nonpsychotic mental disorder. Risk of stroke during follow-up (5-42 years) was calculated with Cox proportional hazards models. Objective baseline measures of fitness and cognition were included in the models in a second set of analyses. RESULTS: There were 7770 first-time stroke events. In adjusted models, increased risk for stroke was observed in men diagnosed with depressive/neurotic disorders (hazard ratio [HR], 1.23; 95% confidence interval [CI], 1.11-1.37), personality disorders (HR, 1.52; 95% CI, 1.29-1.78), and alcohol/substance use disorders (HR, 1.61; 95% CI, 1.41-1.83) at conscription. Corresponding figures for fatal stroke were HR, 1.38; 95% CI, 1.06 to 1.79; HR, 2.26; 95% CI, 1.60 to 3.19; and HR, 2.20; 95% CI, 1.63 to 2.96. HRs for stroke were attenuated when fitness level and intelligence quotient were introduced. Associations remained significant for personality disorders and alcohol/substance use in the fully adjusted models. The interaction term was statistically significant for fitness but not for intelligence quotient. CONCLUSIONS: Our findings suggest that fitness may modify associations between nonpsychotic disorders and stroke. It remains to be clarified whether interventions designed to improve fitness in mentally ill youth can influence future risk of early stroke.

Caspase inhibition impaired the neural stem/progenitor cell response after cortical ischemia in mice.

Cortical ischemia induces proliferation of neural stem/progenitor cells (NSPCs) in the subventricular zone (SVZ) and provokes migration of these cells toward the injured area. Despite sustained migration of NSPCs for an extended period of time after injury, they do not appear to survive. Here, we hypothesized that the anti-apoptotic broad-spectrum caspase inhibitor Q-VD-OPh would increase NSPC survival in the injured cortex. However, contrary to our expectations, caspase inhibition did not promote NSPC survival and cortical neurogenesis. On the contrary, it abolished ischemia-induced proliferation and decreased the number of migrating neuroblasts in the injured cortex. Moreover, caspase inhibition decreased the levels of the chemoattractant chemokine CCL2 (MCP-1) and the pro-inflammatory cytokine IL-1ß. We hence for the first time show that caspase inhibition abrogates the response of NSPCs to an ischemic injury, presumably by inhibiting the production of pro-inflammatory factors. Thus, caution is warranted if anti-apoptotic strategies are applied for neuroprotection.