Transient changes in inflammatory and oxidative stress markers with total sleep deprivation

Dual roles of interleukin-33 in cognitive function by regulating central nervous system inflammation

With the advent of an aging society, the incidence of dementia is increasing, resulting in a vast burden on society. It is increasingly acknowledged that neuroinflammation is implicated in various neurological diseases with cognitive dysfunction such as Alzheimer’s disease, multiple sclerosis, ischemic stroke, traumatic brain injury, and central nervous system infections. As an important neuroinflammatory factor, interleukin-33 (IL-33) is highly expressed in various tissues and cells in the mammalian brain, where it plays a role in the pathogenesis of a number of central nervous system conditions. Reams of previous studies have shown that IL-33 has both pro- and anti-inflammatory effects, playing dual roles in the progression of diseases linked to cognitive impairment by regulating the activation and polarization of immune cells, apoptosis, and synaptic plasticity. This article will summarize the current findings on the effects IL-33 exerts on cognitive function by regulating neuroinflammation, and attempt to explore possible therapeutic strategies for cognitive disorders based on the adverse and protective mechanisms of IL-33.

Acute sleep deprivation immediately increases serum GDNF, BDNF and VEGF levels in healthy subjects

Acute sleep deprivation upregulates hippocampal neurogenesis. Neurotrophic factors such as glial cell line-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), and vascular endothelial growth factor (VEGF) are mediators of neuronal plasticity and neurogenesis. These neurotrophins are involved in sleep and sleep disorders and are associated with sleep deprivation. In this study, it is aimed to investigate the changes of neurotrophin levels with total sleep deprivation in healthy individuals. Seventeen healthy young adults with a mean age of 19.8 (SD = 1.0) years underwent an experimental protocol consisting of 36 h of total sleep deprivation. Venous blood samples were obtained on Day1 at 09.00, on Day2 at 09.00, and at 21.00. Serum levels of neurotrophins were detected using the ELISA method. The participants were asked to mark the scores corresponding to their subjective energy, happiness, depression, tension levels on the visual analog scale; and sleepiness level on the Epworth Sleepiness Scale; during the course of the study. As a result of 36 h of sleep deprivation, serum GDNF, BDNF, and VEGF levels showed a statistically significant increase compared to the baseline values in the participants included in the study (P < 0.0001). While this increase was evident in 24 h, it continued after 36 h. In parallel, sleepiness levels, subjective depression, and tension levels increased, on the other hand, subjective energy and happiness scores decreased at a statistically significant level at the end of the study compared to basal values (P < 0.0001). The results show that acute sleep deprivation significantly affects and increases serum levels of neurotrophic factors, and it seems that these effects are likely to occur as an immediate response to the stress and disruption caused by sleep deprivation.

Premature Aging Among Trauma Survivors-The Longitudinal Implications of Sleep Disruptions on Telomere Length and Cognitive Performance

OBJECTIVES

Sleep is necessary for brain function as well as physical and cognitive processes. Sleep disruptions, common with aging, intensify among trauma survivors. Moreover, former prisoners-of-war (ex-POWs) often experience premature aging. This study investigates the longitudinal effects of sleep disruptions for ex-POWs in relation to cognitive performance and telomere length as well as between cognition and telomeres.

METHOD

This study included Israeli veterans from the 1973 Yom Kippur War who participated in four assessments (1991, 2003, 2008, 2015): (a) ex-POWs (n = 99), and (b) veterans who not were captured (controls) (n = 101). Among both groups, sleep disruptions were assessed using a self-report item in all four assessments. Cognitive performance was assessed using the Montreal Cognitive Assessment (MOCA) and telomere length was assessed via total white blood cells (leukocytes) from whole blood samples using Southern blot, both were measured only among ex-POWs in 2015. We conducted descriptive statistics, repeated measures, correlations, and path analyses.

RESULTS

Sleep disruptions were related to lower cognitive performance but not to shorter telomeres. Moreover, cognitive performance and telomere length were found to be related when sleep disruptions were taken into consideration.

CONCLUSION

Interpersonal trauma was shown to be a unique experience resulting in sleep disruptions over time, leading to cognitive impairment. These findings highlight the importance of viewing trauma survivors at high-risk for sleep disruptions. Therefore, it is imperative to inquire about sleep and diagnose cognitive disorders to help identify and treat premature aging.

Repetitive Religious Chanting Invokes Positive Emotional Schema to Counterbalance Fear: A Multi-Modal Functional and Structural MRI Study

Introduction

During hard times, religious chanting/praying is widely practiced to cope with negative or stressful emotions. While the underlying neural mechanism has not been investigated to a sufficient extent. A previous event-related potential study showed that religious chanting could significantly diminish the late-positive potential induced by negative stimuli. However, the regulatory role of subcortical brain regions, especially the amygdala, in this process remains unclear. This multi-modal MRI study aimed to further clarify the neural mechanism underlying the effectiveness of religious chanting for emotion regulation.

Methodology

Twenty-one participants were recruited for a multi-modal MRI study. Their age range was 40–52 years, 11 were female and all participants had at least 1 year of experience in religious chanting. The participants were asked to view neutral/fearful pictures while practicing religious chanting (i.e., chanting the name of Buddha Amitābha), non-religious chanting (i.e., chanting the name of Santa Claus), or no chanting. A 3.0 T Philips MRI scanner was used to collect the data and SPM12 was used to analyze the imaging data. Voxel-based morphometry (VBM) was used to explore the potential hemispheric asymmetries in practitioners.

Results

Compared to non-religious chanting and no chanting, higher brain activity was observed in several brain regions when participants performed religious chanting while viewing fearful images. These brain regions included the fusiform gyrus, left parietal lobule, and prefrontal cortex, as well as subcortical regions such as the amygdala, thalamus, and midbrain. Importantly, significantly more activity was observed in the left than in the right amygdala during religious chanting. VBM showed hemispheric asymmetries, mainly in the thalamus, putamen, hippocampus, amygdala, and cerebellum; areas related to skill learning and biased memory formation.

Conclusion

This preliminary study showed that repetitive religious chanting may induce strong brain activity, especially in response to stimuli with negative valence. Practicing religious chanting may structurally lateralize a network of brain areas involved in biased memory formation. These functional and structural results suggest that religious chanting helps to form a positive schema to counterbalance negative emotions. Future randomized control studies are necessary to confirm the neural mechanism related to religious chanting in coping with stress and negative emotions.