Inflammation and Cognition in Depression: A Narrative Review

The authors aim to present a narrative review of research on the inflammatory aetiology of depression. Depression is a psychiatric disorder, constituting the most common reason of disability due to a health condition. It has been estimated that at least one in six people suffer from depression at some point of their lives. The aetiology of depression, although researched extensively all around the world, still remains unclear. Authors discuss the possible role of inflammation in depression, the neurodevelopmental theory of depression as well as associations between cognition and depression. Possible associations between memory dysfunction among depressive patients and inflammatory markers are included. The associations between the immune system, depression and cognition are observed. Possible mediating factors between these areas include personality traits, hormonal imbalance and functioning of the brain areas. The question as to what mediating factors are involved is still open to research.

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Neuronal spreading and plaque induction of intracellular Aβ and its disruption of Aβ homeostasis

Acta Neuropathologica ◽

10.1007/s00401-021-02345-9 ◽

2021 ◽

Author(s):

Tomas T. Roos ◽

Megg G. Garcia ◽

Isak Martinsson ◽

Rana Mabrouk ◽

Bodil Israelsson ◽

...

Keyword(s):

Brain Homogenate ◽

Fold Increase ◽

Amyloid Beta Peptide ◽

Intracellular Accumulation ◽

Brain Areas ◽

Cellular Models ◽

Beta Peptide ◽

The Brain

AbstractThe amyloid-beta peptide (Aβ) is thought to have prion-like properties promoting its spread throughout the brain in Alzheimer’s disease (AD). However, the cellular mechanism(s) of this spread remains unclear. Here, we show an important role of intracellular Aβ in its prion-like spread. We demonstrate that an intracellular source of Aβ can induce amyloid plaques in vivo via hippocampal injection. We show that hippocampal injection of mouse AD brain homogenate not only induces plaques, but also damages interneurons and affects intracellular Aβ levels in synaptically connected brain areas, paralleling cellular changes seen in AD. Furthermore, in a primary neuron AD model, exposure of picomolar amounts of brain-derived Aβ leads to an apparent redistribution of Aβ from soma to processes and dystrophic neurites. We also observe that such neuritic dystrophies associate with plaque formation in AD-transgenic mice. Finally, using cellular models, we propose a mechanism for how intracellular accumulation of Aβ disturbs homeostatic control of Aβ levels and can contribute to the up to 10,000-fold increase of Aβ in the AD brain. Our data indicate an essential role for intracellular prion-like Aβ and its synaptic spread in the pathogenesis of AD.

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COVID-19 Beyond the Lungs

10.4018/978-1-7998-8225-1.ch007 ◽

2022 ◽

pp. 109-126

Author(s):

Omar El Hiba ◽

Hicham Chatoui ◽

Nadia Zouhairi ◽

Lahoucine Bahi ◽

Lhoussaine Ammouta ◽

...

Keyword(s):

Experimental Data ◽

Nervous System ◽

Clinical Symptoms ◽

Case Reports ◽

The World ◽

Acute Pneumonia ◽

The Brain ◽

Cardinal Feature ◽

Shed Light

Since December 2019, the world has been shaken by the spread of a highly pathogen virus, causing severe acute respiratory syndrome (SARS-Cov2), which emerged in Wuhan, China. SARS-Cov2 is known to cause acute pneumonia: the cardinal feature of coronavirus disease 2019 (COVID-19). Clinical features of the disease include respiratory distress, loss of spontaneous breathing, and sometimes neurologic signs such as headache and nausea and anosmia, leading to suppose a possible involvement of the nervous system as a potential target of SARS-CoV2. The chapter will shed light on the recent clinical and experimental data sustaining the involvement of the nervous system in the pathophysiology of COVID-19, based on several case reports and experimental data reporting the possible transmission of SARS-CoV2 throughout the peripheral nerves to the brain cardiorespiratory centers. Thus, understanding the role of the nervous system in the course of clinical symptoms of COVID-19 is important in determining the appropriate therapeutic approach to combat the disease.

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Understanding as Living

Living Religion ◽

10.1093/oso/9780190927387.003.0002 ◽

2019 ◽

pp. 7-53

Author(s):

James W. Jones

Keyword(s):

Sensory Experience ◽

Laboratory Research ◽

Interactive System ◽

The World ◽

Human Understanding ◽

Research Findings ◽

Network Studies ◽

The Brain ◽

Religious Understanding

Drawing upon clinical psychoanalysis and laboratory research, this chapter develops an “embodied-relational” epistemology. The chapter reviews major research findings on the ways embodiment influences the cognitive processes by which we understand ourselves and the world. It also reviews current neuro-network studies whose findings imply the brain can be understood as a single, interactive system and not simply a collection of relatively autonomous domains. The emphasis here is on the brain’s complexity, integration, and a certain degree of openness. Sensory experience is understood as an active, not passive process, involving an intimate interconnection between self and world. The role of proprioception, as well as the five basic senses, is analyzed. The implications of such research findings for human understanding, and especially religious understanding, are elaborated.

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Synchronization in the connectome: Metastable oscillatory modes emerge from interactions in the brain spacetime network

10.1101/2022.01.06.475196 ◽

2022 ◽

Author(s):

Joana Cabral ◽

Francesca Castaldo ◽

Jakub Vohryzek ◽

Vladimir Litvak ◽

Christian Bick ◽

...

Keyword(s):

Coupled Oscillators ◽

Brain Activity ◽

Power Spectra ◽

Brain Areas ◽

Neural Mass ◽

Spatially Distributed ◽

Weakly Stable ◽

Human Brains ◽

The Brain

A rich repertoire of oscillatory signals is detected from human brains with electro- and magnetoencephalography (EEG/MEG). However, the principles underwriting coherent oscillations and their link with neural activity remain unclear. Here, we hypothesise that the emergence of transient brain rhythms is a signature of weakly stable synchronization between spatially distributed brain areas, occurring at network-specific collective frequencies due to non-negligible conduction times. We test this hypothesis using a phenomenological network model to simulate interactions between neural mass potentials (resonating at 40Hz) in the structural connectome. Crucially, we identify a critical regime where metastable oscillatory modes emerge spontaneously in the delta (0.5-4Hz), theta (4-8Hz), alpha (8-13Hz) and beta (13-30Hz) frequency bands from weak synchronization of subsystems, closely approximating the MEG power spectra from 89 healthy individuals. Grounded in the physics of delay-coupled oscillators, these numerical analyses demonstrate the role of the spatiotemporal connectome in structuring brain activity in the frequency domain.

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Regulation of metallothionein concentrations in rat brain: effect of glucocorticoids, zinc, copper, and endotoxin

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1994.266.5.e760 ◽

1994 ◽

Vol 266 (5) ◽

pp. E760-E767 ◽

Cited By ~ 2

Author(s):

T. Gasull ◽

M. Giralt ◽

J. Hernandez ◽

P. Martinez ◽

I. Bremner ◽

...

Keyword(s):

Frontal Cortex ◽

Rat Brain ◽

Medulla Oblongata ◽

Adrenocorticotropic Hormone ◽

Brain Areas ◽

Deficient Diet ◽

Zinc Deficient Diet ◽

The Brain

The effects of known inducers of liver metallothionein (MT) synthesis on MT concentrations in the rat brain have been determined using antibodies that are specific for MT I and II and do not cross-react with MT III. There were substantial differences in the MT concentrations in different areas of the brain. Dexamethasone increased MT levels after 24 h in the frontal cortex, cortex, medulla oblongata plus pons, midbrain, striatum, hippocampus, and cerebellum but not in the hypothalamus. Corticosterone produced similar results except in the hippocampus. Long-lasting adrenocorticotropic hormone increased MT concentrations after 12 h in midbrain and striatum but not in the liver. Adrenalectomy decreased MT concentrations after 6 days in the medulla oblongata plus pons, striatum, hippocampus, and hypothalamus but increased concentrations in the liver and kidneys; these effects were reversed by corticosterone. The role of glucocorticoids in the regulation of MT levels therefore differs between tissues and within specific areas of the brain. Injection of zinc or copper intracerebroventricularly and the use of a zinc-deficient diet increased and decreased MT levels, respectively, in some but not all brain areas. Endotoxin increased liver MT but not brain MT I levels after 8 h.

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Naïve to expert: Considering the role of previous knowledge in memory

Brain and Neuroscience Advances ◽

10.1177/2398212820948686 ◽

2020 ◽

Vol 4 ◽

pp. 239821282094868

Author(s):

Alejandra Alonso ◽

Jacqueline van der Meij ◽

Dorothy Tse ◽

Lisa Genzel

Keyword(s):

Memory Retrieval ◽

Special Focus ◽

Previous Knowledge ◽

Research Subjects ◽

Brain Areas ◽

Memory Research ◽

The World ◽

Human Animal ◽

Time Point

In humans, most of our new memories are in some way or another related to what we have already experienced. However, in memory research, especially in non-human animal research, subjects are often mostly naïve to the world. But we know that previous knowledge will change how memories are processed and which brain areas are critical at which time point. Each process from encoding, consolidation, to memory retrieval will be affected. Here, we summarise previous knowledge effects on the neurobiology of memory in both humans and non-human animals, with a special focus on schemas – associative network structures. Furthermore, we propose a new theory on how there may be a continuous gradient from naïve to expert, which would modulate the importance and role of brain areas, such as the hippocampus and prefrontal cortex.

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Melatonin and its relationships with diabetes and obesity: a literature review

Current Diabetes Reviews ◽

10.2174/1573399816666200727102357 ◽

2020 ◽

Vol 16 ◽

Author(s):

Ana Valéria Garcia Ramirez ◽

Durval Ribas Filho ◽

Larissa Bianca Paiva Cunha de Sá ◽

Alberto Krayyem Arbex

Keyword(s):

Metabolic Diseases ◽

Adult Population ◽

Narrative Review ◽

Obese People ◽

Double Blind ◽

Risks And Benefits ◽

The World ◽

Diabetes And Obesity ◽

World Ranking

Significance: Obesity is a multifactorial disease with many risks to public health, affecting 39.6% of American adults and 18.5% of young people. Brazil ranks fifth in the world ranking, with about 18 million obese people. It is estimated that 415 million people live with diabetes in the world, which is roughly 1 in 11 of the world's adult population. This is expected to rise to 642 million people living with diabetes worldwide by 2040. In this scenario, Melatonin has evidenced an important function in the regulation of energy metabolism. Objective: to carry out a broad narrative review of the literature on the main aspects of the influence of melatonin on Diabetes Mellitus and obesity. Methods: Article reviews, systematic reviews, prospective studies, retrospective studies, randomized, double-blind, placebo-controlled trials in humans recently published were selected and analyzed. A total of 368 articles were collated and submitted to the eligibility analysis. Subsequently, 215 studies were selected to compose the textual part of the manuscript and 153 to compose the Narrative Review. Results and final considerations: Studies suggest a possible role of melatonin in metabolic diseases such as obesity, T2DM and metabolic syndrome. Intervention studies using this hormone in metabolic diseases are still unclear regarding a possible benefit of it. There is so far no consensus about a possible role of melatonin as an adjuvant in the treatment of metabolic diseases. More studies are necessary to define possible risks and benefits of melatonin as a therapeutic agent.

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Visual stability

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2010.0277 ◽

2011 ◽

Vol 366 (1564) ◽

pp. 468-475 ◽

Cited By ~ 32

Author(s):

David Melcher

Keyword(s):

Cognitive Neuroscience ◽

State Of The Art ◽

Brain Regions ◽

Clinical Neurology ◽

Visual Stability ◽

Retinal Motion ◽

Brain Circuits ◽

The World ◽

The Brain

Our vision remains stable even though the movements of our eyes, head and bodies create a motion pattern on the retina. One of the most important, yet basic, feats of the visual system is to correctly determine whether this retinal motion is owing to real movement in the world or rather our own self-movement. This problem has occupied many great thinkers, such as Descartes and Helmholtz, at least since the time of Alhazen. This theme issue brings together leading researchers from animal neurophysiology, clinical neurology, psychophysics and cognitive neuroscience to summarize the state of the art in the study of visual stability. Recently, there has been significant progress in understanding the limits of visual stability in humans and in identifying many of the brain circuits involved in maintaining a stable percept of the world. Clinical studies and new experimental methods, such as transcranial magnetic stimulation, now make it possible to test the causal role of different brain regions in creating visual stability and also allow us to measure the consequences when the mechanisms of visual stability break down.

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Learning to see in 3D with two eyes: the role of experience, plasticity and neurochemistry

The Biochemist ◽

10.1042/bio20200059 ◽

2020 ◽

Vol 42 (5) ◽

pp. 12-17

Author(s):

Betina Ip ◽

Holly Bridge

Keyword(s):

Cerebral Cortex ◽

Binocular Vision ◽

Early Experience ◽

Fine Tuning ◽

Computational Power ◽

The World ◽

Accurate Performance ◽

The Brain ◽

Binocular Depth

Humans, along with other predators, have forward-facing eyes which restrict the area of the world that can be seen when compared to animals with eyes on the side of the head. Why would we sacrifice this panoramic vision? The answer is the very precise ability that having two eyes with overlapping and slightly different viewpoints provides to determine fine differences in depth. While interpreting this type of ‘binocular depth’ appears effortless, the precise calculations necessary for perceiving binocular depth require significant computational power in the cerebral cortex and the fine tuning of neurochemical interactions. This processing occurs in the visual regions of the brain and must be honed through early experience for accurate performance. By considering each stage of binocular processing and the neurochemical interactions required for integrating signals from the two eyes, we can begin to understand how the inherent ability of the brain to learn might help us when binocular vision goes wrong.

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Histone Deacetylases and Their Isoform-Specific Inhibitors in Ischemic Stroke

Biomedicines ◽

10.3390/biomedicines9101445 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1445

Author(s):

Svetlana Demyanenko ◽

Valentina Dzreyan ◽

Svetlana Sharifulina

Keyword(s):

Ischemic Stroke ◽

Cerebral Ischemia ◽

Histone Deacetylases ◽

Histone Deacetylase Inhibitors ◽

Neuroprotective Activity ◽

Stroke Therapy ◽

Brain Areas ◽

Histone Deacetylases Inhibitors ◽

The Brain

Cerebral ischemia is the second leading cause of death in the world and multimodal stroke therapy is needed. The ischemic stroke generally reduces the gene expression due to suppression of acetylation of histones H3 and H4. Histone deacetylases inhibitors have been shown to be effective in protecting the brain from ischemic damage. Histone deacetylases inhibitors induce neurogenesis and angiogenesis in damaged brain areas promoting functional recovery after cerebral ischemia. However, the role of different histone deacetylases isoforms in the survival and death of brain cells after stroke is still controversial. This review aims to analyze the data on the neuroprotective activity of nonspecific and selective histone deacetylase inhibitors in ischemic stroke.

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