Involvement of brain-derived neurotrophic factor signaling in the pathogenesis of stress-related brain diseases

Inhibition of PDE4B ameliorates cognitive defects in the model of alcoholic dementia in 3xTg-AD mice via PDE4B/cAMP/PKA signaling

BACKGROUND

Chronic, heavy alcohol use may lead to permanent brain damage, cognitive impairment, and dementia. One of the most serious consequences is alcoholic dementia (AlD). Phosphodiesterase-4 (PDE4) inhibitors have been shown to exhibit beneficial effects on cognition deficits and alcoholism. However, it is not known whether PDE4 inhibitors can be used to treat AlD. A33, a relatively selective PDE4B inhibitor, is absent of the emetic effect associated with PDE4D. The effect of A33 on memory and cognition in AlD remains unclear.

METHODS

We investigated the effects of A33 and the PDE4 inhibitor rolipram on memory and cognition using an AlD animal model, that is, APP/PS1/Tau mice drinking alcohol in the 2-bottle choice test, with or without A33 or rolipram treatment for 3 weeks. The animal groups were compared in behavioral tests related to learning and memory. Neurochemical measures were conducted to explore the underlying mechanism of A33.

RESULTS

Compared to wild-type controls, AlD mice showed impairments of learning ability and memory in the behavior tests; this was attenuated by treatment of rolipram or A33. In addition, administration of rolipram or A33 in AlD mice further alleviated neuropathological alterations in the hippocampus, including Aβ expression and deposition; rolipram or A33 also decreased the levels of inflammatory cytokines, including interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), as well as nuclear factor kappa-B (NF-κB). Further, rolipram or A33 decreased the activation of microglia while increased cyclic adenosine monophosphate (cAMP) levels in the hippocampus of AlD mice.

CONCLUSIONS

These results revealed that the alleviation of the cognitive impairment of AlD in APP/PS1/Tau triple transgenic mice by rolipram or A33 was linked to the action of the PDE4B/cAMP/PKA signaling pathway. A33 can be a promising therapeutic agent for AlD-related cognitive dysfunction.

The Effect of Naringin on Cognitive-Behavioral Functions, CREB/BDNF Signaling, Cholinergic Activity, and Neuronal Density in the Hippocampus of an MSG-Induced Obesity Rat Model

The global rise in obesity and overweight over the past few decades has led to numerous associated disorders, including cognitive deficits. This study evaluate investigates the effects of Naringin (Nar) on memory and learning, anxiety-like behaviors, brain-derived neurotrophic factor (BDNF), cAMP responsive element binding protein (CREB), acetylcholinesterase (AChE) activity, and neuronal density in the CA₁/CA₃ subfields of the hippocampus in an MSG-induced obese obesity rat model. Forty-eight male Wistar rat pups were randomly divided into four groups: Control, MSG, MSG + Nar50, and MSG + Nar100. MSG (4 g/kg BW) was administered subcutaneously in the cervical region from PND 2 to PND10, while Nar (50 mg/kg BW and 100 mg/kg BW) was administered orally from PND30 to PND42. After the treatment period, cognitive (working memory and passive avoidance) and anxiety-related tests (elevated plus maze and novelty-suppressed feeding test) were performed. Subsequently, hippocampal protein level of BDNF and CREB/BDNF gene expression, AChE activity and neuronal density in the CA₁ and CA₃ regions of the hippocampus were measured. Relative to the MSG group, the Nar-treated rats demonstrated improvements in spatial working memory, reduced anxiety-related behaviors, elevated hippocampal CREB and BDNF genes and BDNF protein levels, and reduced AChE activity. Additionally, Nar treatment increased neuronal density in the CA₁/CA₃ subfields of the hippocampus. These findings suggest that Nar enhances cognitive function and mitigates anxiety in MSG-induced obese rats by modulating CREB/BDNF signaling pathway, inhibiting AChE, and exerting neuroprotective effects in the hippocampus.

Neuro-Nutrition and Exercise Synergy: Exploring the Bioengineering of Cognitive Enhancement and Mental Health Optimization

The interplay between nutrition, physical activity, and mental health has emerged as a frontier in bioengineering research, offering innovative pathways for enhancing cognitive function and psychological resilience. This review explores the neurobiological mechanisms underlying the synergistic effects of tailored nutritional strategies and exercise interventions on brain health and mental well-being. Key topics include the role of micronutrients and macronutrients in modulating neurogenesis and synaptic plasticity, the impact of exercise-induced myokines and neurotrophins on cognitive enhancement, and the integration of wearable bioelectronics for personalized monitoring and optimization. By bridging the disciplines of nutrition, psychology, and sports science with cutting-edge bioengineering, this review highlights translational opportunities for developing targeted interventions that advance mental health outcomes. These insights are particularly relevant for addressing global challenges such as stress, anxiety, and neurodegenerative diseases. The article concludes with a roadmap for future research, emphasizing the potential of bioengineered solutions to revolutionize preventive and therapeutic strategies in mental health care.

The Role of Brain-Derived Neurotrophic Factor as an Essential Mediator in Neuronal Functions and the Therapeutic Potential of Its Mimetics for Neuroprotection in Neurologic and Psychiatric Disorders

Among neurotrophins, including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), and neurotrophin-4 (NT-4/5), BDNF has been extensively studied for its physiological role in cell survival and synaptic regulation in the central nervous system's (CNS's) neurons. BDNF binds to TrkB (a tyrosine kinase) with high affinity, and the resulting downstream intracellular signaling cascades play crucial roles in determining cell fate, including neuronal differentiation and maturation of the CNS neurons. It has been well demonstrated that the downregulation/dysregulation of the BDNF/TrkB system is implicated in the pathogenesis of neurologic and psychiatric disorders, such as Alzheimer's disease (AD) and depression. Interestingly, the effects of BDNF mimetic compounds including flavonoids, small molecules which can activate TrkB-mediated signaling, have been extensively investigated as potential therapeutic strategies for brain diseases, given that p75NTR, a common neurotrophin receptor, also contributes to cell death under a variety of pathological conditions such as neurodegeneration. Since the downregulation of the BDNF/TrkB system is associated with the pathophysiology of neurodegenerative diseases and psychiatric disorders, understanding how alterations in the BDNF/TrkB system contribute to disease progression could provide valuable insight for the prevention of these brain diseases. The present review shows recent advances in the molecular mechanisms underlying the BDNF/TrkB system in neuronal survival and plasticity, providing critical insights into the potential therapeutic impact of BDNF mimetics in the pathophysiology of brain diseases.

BDNF-TrkB Signaling in Mitochondria: Implications for Neurodegenerative Diseases

Brain-derived neurotrophic factor (BDNF) plays a pivotal role in neuronal development, synaptic plasticity, and overall neuronal health by binding to its receptor, tyrosine receptor kinase B (TrkB). This review delves into the intricate mechanisms through which BDNF-TrkB signaling influences mitochondrial function and potentially influences pathology in neurodegenerative diseases. This review highlights the BDNF-TrkB signaling pathway which regulates mitochondrial bioenergetics, biogenesis, and dynamics, mitochondrial processes vital for synaptic transmission and plasticity. Furthermore, we explore how the BDNF-TrkB-PKA signaling in the cytosol and in mitochondria affects mitochondrial transport and distribution and mitochondrial content, which is crucial for supporting the energy demands of synapses. The dysregulation of this signaling pathway is linked to various neurodegenerative diseases, including Alzheimer's and Parkinson's disease, which are characterized by mitochondrial dysfunction and reduced BDNF expression. By examining seminal studies that have characterized this signaling pathway in health and disease, the present review underscores the potential of enhancing BDNF-TrkB signaling to mitigate mitochondrial dysfunction in neurodegenerative diseases, offering insights into therapeutic strategies to enhance neuronal resilience and function.

Effects of Repetitive Transcranial Magnetic Stimulation on Tumor Necrosis Factor Alpha in Neuropsychological Disorders: A Systematic Review and Meta-Analysis

INTRODUCTION

Repetitive transcranial magnetic stimulation (rTMS) shows promise in treating neuropsychological disorders. This systematic review and meta-analysis investigated the effects of rTMS on inflammatory cytokines and brain-derived neurotrophic factor (BDNF) under these conditions.

METHOD

We searched five electronic databases for relevant studies. Twelve studies (six randomized controlled trials [RCTs] and six cohort studies) were included in the systematic review, with six RCTs included in the meta-analysis. The primary outcome was tumor necrosis factor-alpha (TNF-α) levels, with secondary outcomes including interleukin-6 (IL-6), interleukin-1 beta (IL-1β), high-sensitivity C-reactive protein (hs-CRP), interferon-gamma (IFN-γ), and BDNF.

RESULTS

Meta-analysis revealed a significant decrease in TNF-α levels after rTMS (weighted mean difference [WMD]: -6.65, 95% confidence interval [CI]: -10.47-2.83, p < 0.05), with greater effects associated with longer interventions. No significant change was found in the IL-6 levels. BDNF levels increased significantly (WMD: 7.97, 95% CI: 2.8-13.15, p < 0.05). Qualitative synthesis indicated consistent reductions in IL-1β. High heterogeneity was observed in some analyses.

CONCLUSION

rTMS may exert therapeutic effects on neuropsychological disorders partly through modulating neuroinflammation and promoting neuroplasticity. However, high heterogeneity and study limitations necessitate larger, more standardized clinical trials to confirm these effects and explore their clinical significance.

Unveiling the Mechanisms of a Remission in Major Depressive Disorder (MDD)-like Syndrome: The Role of Hippocampal Palmitoyltransferase Expression and Stress Susceptibility

Post-translational modifications of proteins via palmitoylation, a thioester linkage of a 16-carbon fatty acid to a cysteine residue, reversibly increases their affinity for cholesterol-rich lipid rafts in membranes, changing their function. Little is known about how altered palmitoylation affects function at the systemic level and contributes to CNS pathology. However, recent studies suggested a role for the downregulation of palmitoyl acetyltransferase (DHHC) 21 gene expression in the development of Major Depressive Disorder (MDD)-like syndrome. Here, we sought to investigate how susceptibility (sucrose preference below 65%) or resilience (sucrose preference > 65%) to stress-induced anhedonia affects DHHC gene expression in the hippocampus of C57BL/6J mice during the phase of spontaneous recovery from anhedonia. Because MDD is a recurrent disorder, it is important to understand the molecular mechanisms underlying not only the symptomatic phase of the disease but also a state of temporary remission. Indeed, molecular changes associated with the application of pharmacotherapy at the remission stage are currently not well understood. Therefore, we used a mouse model of chronic stress to address these questions. The stress protocol consisted of rat exposure, social defeat, restraint stress, and tail suspension. Mice from the stress group were not treated, received imipramine via drinking water (7 mg/kg/day), or received intraperitoneal injections of dicholine succinate (DS; 25 mg/kg/day) starting 7 days prior to stress and continuing during a 14-day stress procedure. Controls were either untreated or treated with either of the two drugs. At the 1st after-stress week, sucrose preference, forced swim, novel cage, and fear-conditioning tests were carried out; the sucrose test and 5-day Morris water maze test followed by a sacrifice of mice on post-stress day 31 for all mice were performed. Transcriptome Illumina analysis of hippocampi was carried out. Using the RT-PCR, the hippocampal gene expression of Dhhc3, Dhhc7, Dhhc8, Dhhc13, Dhhc14, and Dhhc21 was studied. We found that chronic stress lowered sucrose preference in a subgroup of mice that also exhibited prolonged floating behavior, behavioral invigoration, and impaired contextual fear conditioning, while auditory conditioning was unaltered. At the remission phase, no changes in the sucrose test were found, and the acquisition of the Morris water maze was unchanged in all groups. In anhedonic, but not resilient animals, Dhhc8 expression was lowered, and the expression of Dhhc14 was increased. Antidepressant treatment with either drug partially preserved gene expression changes and behavioral abnormalities. Our data suggest that Dhhc8 and Dhhc14 are likely to be implicated in the mechanisms of depression at the remission stage, serving as targets for preventive therapy.

Role of sleep and neurochemical biomarkers in synaptic plasticity related to neurological and psychiatric disorders: A scoping review

Sleep is vital for maintaining physical and mental well-being, impacting cognitive functions like memory and learning through neuroplasticity. Sleep disturbances prevalent in neurological and psychiatric disorders exacerbate cognitive decline, imposing societal burdens. Exploring the relationship between sleep and neuroplasticity elucidates the mechanisms influencing cognition, particularly amidst the prevalent sleep disturbances in these clinical populations. While existing reviews provide valuable insights, gaps remain in understanding the neurophysiological mechanisms underlying sleep and cognitive function. This scoping review aims to investigate the characteristic patterns of sleep parameters and neurochemical biomarkers in reflecting neuroplasticity changes related to neurological and psychiatric disorders and to explore how these markers interact and influence cognition at the molecular level. Studies involving adults and older adults were included, excluding animal models and the paediatric population. Selected studies explored the relationship between sleep parameter or neurochemical biomarker changes and cognitive impairment, reflecting underlying neuroplasticity changes. Peer-reviewed articles, clinical trials, theses, and dissertations in English were included while excluding secondary research and non-peer-reviewed sources. A three-step search strategy was executed following the updated Joanna Briggs Institute methodology for scoping reviews. Published studies were retrieved from nine databases, grey literature, expert recommendations, and hand-searching of the included studies' bibliography. A basic qualitative content synthesis of 34 studies was conducted per JBI's scoping review guidance. Slow-wave and Rapid-Eye Movement sleep, sleep spindles, sleep cycle disruption, K-Complex(KC) density, Hippocampal sEEG, BDNF, IL-6, iNOS mRNA expression, plasma serotonin, CSF Aβ-42, t-tau and p-tau proteins, and serum cortisol revealed associations with cognitive dysfunction. Examining the relationship between sleep parameters, neurochemical biomarkers, and cognitive function reveals neuronal mechanisms that guide potential therapeutic interventions and enhance quality patient care.

Depression Treatment: Is There a Role for Botulinum Toxin Type A?

This study aimed to determine whether botulinum toxin type A injected into the muscles of the upper third of the face has antidepressant effects in patients diagnosed with depression. Studies seeking a relationship between botulinum toxin type A and its antidepressant effects were considered in this review. All studies concluded that the facial expression muscles present positive feedback to the brain and enhance mood states. Botulinum toxin when applied to the corrugator and procerus muscles has an antidepressant effect.

The link between BDNF and platelets in neurological disorders

Platelets are considered one of the most important reservoirs not only of growth factors, but also of neurotrophic factors that could contribute to the repair of vascular lesions and the prevention of neurological deterioration. Among these factors, Brain-Derived Neurotrophic Factor (BDNF) - a protein belonging to the neurotrophin family - is widely expressed both in the hippocampus and in platelets. Platelets constitute an important reservoir of BDNF; however, little is known about the factors modulating its release into the circulation and whether anti-platelet drugs affect this secretion. In this review, we have discussed the link between BDNF and platelets and their role in neurological disorders.

The chronic unpredictable mild stress (CUMS) Paradigm: Bridging the gap in depression research from bench to bedside

Depression is a complicated neuropsychiatric condition with an incompletely understoodetiology, making the discovery of effective therapies challenging. Animal models have been crucial in improving our understanding of depression and enabling antidepressant medication development. The CUMS model has significant face validity since it induces fundamental depression symptoms in humans, such as anhedonia, behavioral despair, anxiety, cognitive impairments, and changes in sleep, food, and social behavior. Its construct validity is demonstrated by the dysregulation of neurobiological systems involved in depression, including monoaminergic neurotransmission, the hypothalamic-pituitary-adrenal axis, neuroinflammatory processes, and structural brain alterations. Critically, the model's predictive validity is demonstrated by the reversal of CUMS-induced deficits following treatment with clinically effective antidepressants such as selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, tricyclic antidepressants, and monoamine oxidase inhibitors. This review comprehensivelyassesses the multifarious depressive-like phenotypes in the CUMS model using behavioral paradigms like sucrose preference, forced swim, tail suspension, elevated plus maze, and novel object recognition tests. It investigates the neurobiological mechanisms that underlie CUMS-induced behaviors, including signaling pathways involving tumor necrosis factor-alpha, brain-derived neurotrophic factor and its receptor TrkB, cyclooxygenase-2, glycogen synthase kinase-3 beta, and the kynurenine pathway. This review emphasizes the CUMS model's importance as a translationally relevant tool for unraveling the complex mechanisms underlying depression and facilitating the development of improved and targeted interventions for this debilitating neuropsychiatric disorder by providing a comprehensive overview of its validity, behavioral assessments, and neurobiological underpinnings.

Stimulating myelin restoration with BDNF: a promising therapeutic approach for Alzheimer's disease

Alzheimer's Disease (AD) is a chronic neurodegenerative disorder constituting the most common form of dementia (60%-70% of cases). Although AD presents majorly a neurodegenerative pathology, recent clinical evidence highlights myelin impairment as a key factor in disease pathogenesis. The lack of preventive or restorative treatment is emphasizing the need to develop novel therapeutic approaches targeting to the causes of the disease. Recent studies in animals and patients have highlighted the loss of myelination of the neuronal axons as an extremely aggravating factor in AD, in addition to the formation of amyloid plaques and neurofibrillary tangles that are to date the main pathological hallmarks of the disease. Myelin breakdown represents an early stage event in AD. However, it is still unclear whether myelin loss is attributed only to exogenous factors like inflammatory processes of the tissue or to impaired oligodendrogenesis as well. Neurotrophic factors are well established protective molecules under many pathological conditions of the neural tissue, contributing also to proper myelination. Due to their inability to be used as drugs, many research efforts are focused on substituting neurotrophic activity with small molecules. Our research team has recently developed novel micromolecular synthetic neurotrophin mimetics (MNTs), selectively acting on neurotrophin receptors, and thus offering a unique opportunity for innovative therapies against neurodegenerative diseases. These small sized, lipophilic molecules address the underlying biological effect of these diseases (neuroprotective action), but also they exert significant neurogenic actions inducing neuronal replacement of the disease areas. One of the significant neurotrophin molecules in the Central Nervous System is Brain-Derived-Neurotrophin-Factor (BDNF). BDNF is a neurotrophin that not only supports neuroprotection and adult neurogenesis, but also mediates pro-myelinating effects in the CNS. BDNF binds with high-affinity on the TrkB neurotrophin receptor and enhances myelination by increasing the density of oligodendrocyte progenitor cells (OPCs) and playing an important role in CNS myelination. Conclusively, in the present review, we discuss the myelin pathophysiology in Alzheimer's Diseases, as well as the role of neurotrophins, and specifically BDNF, in myelin maintenance and restoration, revealing its valuable therapeutic potential against AD.

Neuroprotective Effects of Dehydroepiandrosterone and Hericium erinaceus in Scopolamine-induced Alzheimer's Diseases-like Symptoms in Male Rats

BACKGROUND

The neuroprotective effects of Dehydroepiandrosterone (DHEA) and Hericium erinaceus (H. erinaceus) mushroom extract against scopolamine-induced Alzheimer's disease-like symptoms in male Wistar rats were investigated.

METHODS

Sixty-four male Wistar rats were divided into eight groups (n = 8). Scopolamine (SCO) was intraperitoneally injected at a dose of 1 mg/kg/day for 10 days. The treatment groups orally received DHEA (250 mg/kg/day) and/or H. erinaceus (300 mg/kg/day) for 14 days. Afterward, the Morris water maze (MWM) and novel object recognition tests were implemented. Then, animals were anesthetized and the brain tissue samples were separated. Levels of lipid peroxidation (LPO), total antioxidant capacity (TAC), catalase activity (CAT), and brain-derived neurotrophic factor (BDNF) were determined. Also, histopathological studies were evaluated in the brain tissue samples.

RESULTS

Administration of SCO significantly decreased spatial and cognitive memory (p < 0.001). Not only did SCO injection significantly increase the levels of the LPO but also the SCO markedly reduced the levels of the TAC, CAT activity, and the BDNF in the brain tissue. On the other hand, a combination of the DHEA and H. erinaceus showed higher efficacy than the DHEA or H. erinaceus in attenuating behavioral anomalies and improving the antioxidant defense system and BDNF levels. Histological examination was well correlated with biochemical findings regarding SCO neurodegeneration and DHEA and/or H. erinaceus neuroprotection.

CONCLUSION

Interestingly, ADHE and/or H. erinaceus may due to their potential neurotrophic properties be used as a new and beneficial concurrent therapy in the treatment of Alzheimer's disease-like symptoms caused by SCO.

Indole-3-Carbinol and Its Derivatives as Neuroprotective Modulators

Brain-derived neurotrophic factor (BDNF) and its downstream tropomyosin receptor kinase B (TrkB) signaling pathway play pivotal roles in the resilience and action of antidepressant drugs, making them prominent targets in psychiatric research. Oxidative stress (OS) contributes to various neurological disorders, including neurodegenerative diseases, stroke, and mental illnesses, and exacerbates the aging process. The nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant responsive element (ARE) serves as the primary cellular defense mechanism against OS-induced brain damage. Thus, Nrf2 activation may confer endogenous neuroprotection against OS-related cellular damage; notably, the TrkB/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway, stimulated by BDNF-dependent TrkB signaling, activates Nrf2 and promotes its nuclear translocation. However, insufficient neurotrophin support often leads to the downregulation of the TrkB signaling pathway in brain diseases. Thus, targeting TrkB activation and the Nrf2-ARE system is a promising therapeutic strategy for treating neurodegenerative diseases. Phytochemicals, including indole-3-carbinol (I3C) and its metabolite, diindolylmethane (DIM), exhibit neuroprotective effects through BDNF's mimetic activity; Akt phosphorylation is induced, and the antioxidant defense mechanism is activated by blocking the Nrf2-kelch-like ECH-associated protein 1 (Keap1) complex. This review emphasizes the therapeutic potential of I3C and its derivatives for concurrently activating neuronal defense mechanisms in the treatment of neurodegenerative diseases.

Sleep rebound leads to marked recovery of prolonged sleep deprivation-induced adversities in the stress response and hippocampal neuroplasticity of male rats

BACKGROUND

Sleep disturbances are not only frequent symptoms, but also risk factors for major depressive disorder. We previously reported that depressed patients who experienced "Hypersomnia" showed a higher and more rapid response rate under paroxetine treatment, but the underlying mechanism remains unclear. The present study was conducted to clarify the beneficial effects of sleep rebound through an experimental "Hypersomnia" rat model on glucocorticoid and hippocampal neuroplasticity associated with antidepressive potency.

METHODS

Thirty-four male Sprague-Dawley rats were subjected to sham treatment, 72-h sleep deprivation, or sleep deprivation and subsequent follow-up for one week. Approximately half of the animals were sacrificed to evaluate adrenal weight, plasma corticosterone level, hippocampal content of mRNA isoforms, and protein of the brain-derived neurotrophic factor (Bdnf) gene. In the other half of the rats, Ki-67- and doublecortin (DCX)-positive cells in the hippocampus were counted via immunostaining to quantify adult neurogenesis.

RESULTS

Prolonged sleep deprivation led to adrenal hypertrophy and an increase in the plasma corticosterone level, which had returned to normal after one week follow-up. Of note, sleep deprivation-induced decreases in hippocampal Bdnf transcripts containing exons II, IV, VI, and IX and BDNF protein levels, Ki-67-(+)-proliferating cells, and DCX-(+)-newly-born neurons were not merely reversed, but overshot their normal levels with sleep rebound.

LIMITATIONS

The present study did not record electroencephalogram or assess behavioral changes of the sleep-deprived rats.

CONCLUSIONS

The present study demonstrated that prolonged sleep deprivation-induced adversities are reversed or recovered by sleep rebound, which supports "Hypersomnia" in depressed patients as having a beneficial pharmacological effect.

Role of Glial Cells in Neuronal Function, Mood Disorders, and Drug Addiction

Mood disorders and substance use disorder (SUD) are of immense medical and social concern. Although significant progress on neuronal involvement in mood and reward circuitries has been achieved, it is only relatively recently that the role of glia in these disorders has attracted attention. Detailed understanding of the glial functions in these devastating diseases could offer novel interventions. Here, following a brief review of circuitries involved in mood regulation and reward perception, the specific contributions of neurotrophic factors, neuroinflammation, and gut microbiota to these diseases are highlighted. In this context, the role of specific glial cells (e.g., microglia, astroglia, oligodendrocytes, and synantocytes) on phenotypic manifestation of mood disorders or SUD are emphasized. In addition, use of this knowledge in the potential development of novel therapeutics is touched upon.

The Effectiveness of Mindfulness in the Treatment of Methamphetamine Addiction Symptoms: Does Neuroplasticity Play a Role?

INTRODUCTION

Methamphetamine is a highly stimulating psychoactive drug that causes life-threatening addictions and affects millions of people around the world. Its effects on the brain are complex and include disturbances in the neurotransmitter systems and neurotoxicity. There are several known treatment methods, but their effectiveness is moderate. It must be emphasised that no drugs have been approved for treatment. For this reason, there is an urgent need to develop new, effective, and safe treatments for methamphetamine. One of the potential treatments is mindfulness meditation. In recent years, this technique has been researched extensively in the context of many neurological and psychiatric disorders.

METHODS

This review explores the use of mindfulness in the treatment of methamphetamine addiction. Searches were conducted in the PubMed/Medline, Research Gate, and Cochrane databases.

RESULTS

Ten studies were identified that used mindfulness-based interventions in the treatment of methamphetamine addiction. The results show that mindfulness is an effective form of reducing hunger, risk of relapses, stress indicators, depression, and aggression, alone or in combination with transcranial direct current stimulation (tDCS). Mindfulness also improved the cognitive function in addicts. The included studies used only behavioural measures. The potential mechanisms of mindfulness in addiction were explained, and it was proposed that it can induce neuroplasticity, alleviating the symptoms of addiction.

CONCLUSIONS

Evidence from the studies suggest that mindfulness may be an effective treatment option for methamphetamine addiction, used alone or in combination with tDCS. However, further high-quality research is required to establish the role of this treatment option in this field. The use of neuroimaging and neurophysiological measures is fundamental to understand the mechanisms of mindfulness.

An Interaction between Brain-Derived Neurotrophic Factor and Stress-Related Glucocorticoids in the Pathophysiology of Alzheimer's Disease

Both the brain-derived neurotrophic factor (BDNF) and glucocorticoids (GCs) play multiple roles in various aspects of neurons, including cell survival and synaptic function. BDNF and its receptor TrkB are extensively expressed in neurons of the central nervous system (CNS), and the contribution of the BDNF/TrkB system to neuronal function is evident; thus, its downregulation has been considered to be involved in the pathogenesis of Alzheimer's disease (AD). GCs, stress-related molecules, and glucocorticoid receptors (GRs) are also considered to be associated with AD in addition to mental disorders such as depression. Importantly, a growing body of evidence suggests a close relationship between BDNF/TrkB-mediated signaling and the GCs/GR system in the CNS. Here, we introduce the current studies on the interaction between the neurotrophic system and stress in CNS neurons and discuss their involvement in the pathophysiology of AD.

Epigenetic Alterations in Post-Traumatic Stress Disorder: Comprehensive Review of Molecular Markers

Background

Post-traumatic stress disorder (PTSD) can occur after a traumatic event. PTSD is characterized by nightmares, flashbacks and avoidance of stressors. It currently affects 2-8% of the population, with military personnel particularly susceptible. Studies show that environmental stressors can induce various epigenetic changes that shape the PTSD phenotype. Despite the significant impact of epigenetic factors on PTSD symptoms and susceptibility, they have not been widely discussed in the literature. This review focuses on describing epigenetic mechanisms in PTSD, especially DNA methylation, chromatin regulation, and noncoding RNA.

Summary

The article includes relevant studies published from 2013 to 2023, excluding non-English-language studies or studies with insufficient data. This review investigated gene methylation changes in association with PTSD, including those related to the hypothalamic-pituitary-adrenal axis, brain-derived neurotrophic factor, neurotransmitters, and immune system functioning, as well as the role of histones and regulatory noncoding RNAs.

Key Messages

Epigenetic alterations play a crucial role in shaping PTSD susceptibility, symptomatology, and long-term outcomes, highlighting their potential as important markers and therapeutic targets. Understanding these alterations can aid in developing clinical strategies to better predict, prevent, and treat PTSD. However, further large-scale longitudinal studies are needed to establish the temporal relationship between epigenetic changes and the onset of PTSD, as well as to classify other potential epigenetic mechanisms.