Beneficial effects of physical exercise on cognitive-behavioral impairments and brain-derived neurotrophic factor alteration in the limbic system induced by neurodegeneration

The molecular basis of music-induced neuroplasticity in humans: A systematic review

Neuroscientific research on music-based activities has grown rapidly, shedding light on the health benefits of music across various domains. However, the molecular mechanisms by which music influences neuroplasticity in humans remain largely unexplored. This review aimed to synthesize and critically appraise existing research on molecular neuroplasticity in humans, with a specific focus on the effects of receptive and active music-based interventions (MBIs) and musical training. Following the PRISMA guidelines, a systematic search was conducted across four databases (MEDLINE, Embase, PsycINFO, and Scopus), for articles published between 2000 and December 2023. From an initial return of 3239 records, 15 studies met the inclusion criteria and were synthesized into three categories of music experiences: (1) receptive MBIs, (2) active MBIs, and (3) musical training. Both active and receptive MBIs were found to enhance neuroplasticity. Specifically, music listening was associated with relaxation and improved immune function, marked by the upregulation of genes related to neuroprotection and synaptic plasticity, while active MBIs consistently enhanced peripheral neurotrophic factors in both healthy and patient populations. Among musicians, neurogenetic alterations linked to music perception and production, neurogenesis, and neurotransmission were identified, with multiple studies highlighting the roles of Brain-Derived Neurotrophic Factor (BDNF), Alpha Synuclein (SNCA), and GATA2 (GATA Binding Protein 2) genes. Collectively, both MBIs and musical training induce neuroplastic changes by modulating neurogenetics, enhancing neurotrophins, altering hormonal levels, and reducing stress in humans. These findings highlight the need for further research to elucidate the molecular mechanisms underlying music's effects on the human brain, which could have implications for advancing therapeutic interventions for neuropsychological disorders.

Semaglutide and High-Intensity Interval Exercise Attenuate Cognitive Impairment in Type 2 Diabetic Mice via BDNF Modulation

Background/Objectives: Diabetes frequently leads to cognitive impairment, encompassing issues with memory and executive function, as well as depression and anxiety. This study examines the impact of high-intensity interval exercise (HIIE) alongside glucagon-like peptide-1 receptor agonist (GLP-1 RA) semaglutide on cognitive dysfunction associated with diabetes. Methods: Db/db mice were divided into a control group, semaglutide group, HIIE group, and semaglutide combined with HIIE group to study metabolic and neurobehavioral effects. Cognitive and behavioral tests, hippocampal morphology, and molecular analyses (APP, BDNF, Aβ, p-Tau, PKA, AMPK) were performed. HT22 cells under high glucose were treated with semaglutide, L-lactate, PKA inhibitor H89, and AMPK inhibitor Compound C to validate mechanisms. Results: Over 8 weeks, both HIIE and semaglutide improved neuronal morphology and cognitive performance while reducing depression in db/db mice. However, the current study observed no synergistic effects. Both therapies decreased Aβ and p-Tau protein levels and increased BDNF levels in the hippocampus, likely through the AMPK and PKA signaling pathways, respectively. In vitro, HT22 cells under high glucose conditions exhibited elevated APP and p-Tau expression and reduced BDNF levels, which could be altered by L-lactate and semaglutide. The AMPK inhibitor Compound C and the PKA inhibitor H89 attenuated the increase in BDNF levels induced by L-lactate and semaglutide, but their combination mitigated this inhibitory effect. This study suggests that while HIIE and semaglutide improve cognitive function and reduce depression via BDNF, their combined use did not show the anticipated synergistic benefits due to potential antagonism between the AMPK and PKA pathways. Conclusions: This has important implications for designing exercise prescriptions for cognitive impairment in diabetics.

Cognitive Stimulation and Its Effects on Well-Being, Executive Functions, and Brain-Derived Neurotrophic Factor in Older Adults from a Mexican Geriatric Center: A Quasi-Experimental Study

Background/Objectives: The progressive increase in the aging population highlights the need for interventions aimed at preserving cognitive health and overall well-being in older adults. This study aimed to assess the impact of a structured cognitive training program on psychological well-being, executive function performance, and Brain-Derived Neurotrophic Factor levels (BDNF) in older adults from a Mexican geriatric center. Methods: A quasi-experimental pretest-posttest design with a nonequivalent control group was conducted. Thirty-two older adults were assigned either to a cognitive stimulation intervention group or a control group. The intervention consisted of 120 individually structured sessions, each lasting approximately 60 min, delivered five times per week over 24 weeks. Independent neuropsychologists, blinded to group allocation, assessed executive function (BANFE-3), depressive symptoms (Yesavage Geriatric Depression Scale), autonomy in daily living (Barthel Index), and quality of life (WHOQOL-OLD) before and after the intervention. Serum BDNF levels were also measured. Results: The intervention group showed significant improvements in executive function, depressive symptoms, independence in daily activities, and quality of life, while the control group showed no changes. Additionally, the intervention group showed an increase in BDNF expression post-intervention. Conclusions: The cognitive stimulation program effectively improved cognitive performance, emotional well-being, autonomy, and quality of life in older adults. These findings highlight the importance of integrating structured cognitive stimulation into geriatric care. For nursing practice, this underscores the key role nurses can play in delivering cognitive interventions to promote cognitive health, independence, and emotional stability among institutionalized and non-institutionalized older adults.

Mitochondrial dysfunction as a key player in aggravating periodontitis among diabetic patients: review of the current scope of knowledge

Periodontitis is a prevalent inflammatory disease that leads to significant periodontal tissue destruction and compromised dental health, with its severity exacerbated in individuals with Diabetes Mellitus (DM). This review explores the complex relationship between mitochondrial dysfunction and periodontitis in diabetic patients. Recent studies indicate that the excessive production of reactive oxygen species (ROS), primarily generated by dysfunctional mitochondrial electron transport chain (ETC) complexes, contributes to oxidative stress (OS) and subsequent periodontal tissue damage. The interplay between impaired mitochondrial biogenesis, apoptosis of periodontal cells, and ROS accumulation highlights a critical area of concern in understanding the pathophysiology of diabetic periodontitis. Furthermore, altered glycemic control due to inflammatory processes associated with periodontitis may perpetuate a cyclical detriment to oral and systemic health. This review aims to highlight the mechanistic roles of mitochondrial dysfunction in the aggravation of periodontitis among diabetic patients, emphasizing further research to identify potential therapeutic targets and improve treatment efficacy for this dual pathology.

Neuroadaptation in neurodegenerative diseases: compensatory mechanisms and therapeutic approaches

Progressive neuronal loss is a hallmark of neurodegenerative diseases including Alzheimer's, Parkinson's, Huntington's, and Amyotrophic Lateral Sclerosis (ALS), which cause cognitive and motor impairment. Delaying the onset and course of symptoms is largely dependent on neuroadaptation, the brain's ability to restructure in response to damage. The molecular, cellular, and systemic processes that underlie neuroadaptation are examined in this study. These mechanisms include gliosis, neurogenesis, synaptic plasticity, and changes in neurotrophic factors. Axonal sprouting, dendritic remodelling, and compensatory alterations in neurotransmitter systems are important adaptations observed in NDDs; nevertheless, these processes may shift to maladaptive plasticity, which would aid in the advancement of the illness. Amyloid and tau pathology-induced synaptic alterations in Alzheimer's disease emphasize compensatory network reconfiguration. Dopamine depletion causes a major remodelling of the basal ganglia in Parkinson's disease, and non-dopaminergic systems compensate. Both ALS and Huntington's disease rely on motor circuit rearrangement and transcriptional dysregulation to slow down functional deterioration. Neuroadaptation is, however, constrained by oxidative stress, compromised autophagy, and neuroinflammation, particularly in elderly populations. The goal of emerging therapy strategies is to improve neuroadaptation by pharmacologically modifying neurotrophic factors, neuroinflammation, and synaptic plasticity. Neurostimulation, cognitive training, and physical rehabilitation are instances of non-pharmacological therapies that support neuroplasticity. Restoring compensating systems may be possible with the use of stem cell techniques and new gene treatments. The goal of future research is to combine biomarkers and individualized medicines to maximize neuroadaptive responses and decrease the course of illness. In order to reduce neurodegeneration and enhance patient outcomes, this review highlights the dual function of neuroadaptation in NDDs and its potential as a therapeutic target.

Alzheimer's, Parkinson's, Frontotemporal Lobar Degeneration, and Amyotrophic Lateral Sclerosis Start in Pediatric Ages: Ultrafine Particulate Matter and Industrial Nanoparticles Are Key in the Early-Onset Neurodegeneration: Time to Invest in Preventive Medicine

Billions of people are exposed to fine particulate matter (PM2.5) levels above the USEPA's annual standard of 9 μg/m3. Common emission sources are anthropogenic, producing complex aerosolized toxins. Ultrafine particulate matter (UFPM) and industrial nanoparticles (NPs) have major detrimental effects on the brain, but the USA does not measure UFPM on a routine basis. This review focuses on the development and progression of common neurodegenerative diseases, as diagnosed through neuropathology, among young residents in Metropolitan Mexico City (MMC). MMC is one of the most polluted megacities in the world, with a population of 22 million residents, many of whom are unaware of the brain effects caused by their polluted atmosphere. Fatal neurodegenerative diseases (such as Alzheimer's and Parkinson's) that begin in childhood in populations living in air polluted environments are preventable. We conclude that UFPM/NPs are capable of disrupting neural homeostasis and give rise to relentless neurodegenerative processes throughout the entire life of the highly exposed population in MMC. The paradigm of reaching old age to have neurodegeneration is no longer supported. Neurodegenerative changes start early in pediatric ages and are irreversible. It is time to invest in preventive medicine.

Hippocampal Apoptosis: Molecular Mechanisms Triggered by Toxic Cannabinoid Exposure: A Narrative Review

Hippocampal apoptosis is increasingly recognized as a significant consequence of toxic cannabinoid exposure, with profound implications for cognitive function and mental health. This narrative review comprehensively examines the molecular mechanisms underlying cannabinoid-induced apoptosis, focusing on the interplay of various bioactive compounds and their effects on neuronal integrity. We begin by discussing the key players in cannabinoid biology, followed by a synthesis of findings from animal and clinical studies that highlight the neurotoxic potential of cannabinoids. Central to our analysis are the roles of neuroinflammation and oxidative stress, which exacerbate neuronal damage and contribute to cell death. The activation of cannabinoid receptors, particularly CB1 and CB2, is scrutinized for its dual role in mediating neuroprotective and neurotoxic effects. We explore calcium dysregulation as a critical mechanism that leads to excitotoxicity, mitochondrial dysfunction, and the activation of pro-apoptotic pathways. Additionally, we address the inhibition of anti-apoptotic proteins, induction of endoplasmic reticulum (ER) stress, and disruption of neurotransmitter systems, all of which further facilitate apoptosis in hippocampal neurons. Alterations in neurotrophic factor levels are also examined, as they play a vital role in neuronal survival and plasticity. Ultimately, this review underscores the multifaceted nature of cannabinoid-induced hippocampal apoptosis and calls for further research to elucidate these complex interactions, aiming to inform clinical practices and public health policies regarding cannabinoid use. The findings presented herein highlight the urgent need for a nuanced understanding of the risks associated with cannabinoid exposure, particularly in vulnerable populations.

Impact of Exercise on Tramadol-Conditioned Place Preference

BACKGROUND

Tramadol (TRA) is an opioid that is used to manage moderate to severe pain. Long-term use of TRA can lead to the development of opioid use disorder.

OBJECTIVES

This study investigates the role of forced exercise in reducing TRA-seeking behavior.

METHODS

Adult male rats (240-260 g) were divided into five groups; the control group received vehicle injections, the TRA group received TRA (75 mg/kg, i.p) every other day for 8 days, and three TRA-exercise groups were forced to run on a treadmill (60 min/day, 5 days/week) for 2, 4, or 6 weeks prior to conditioning with TRA. A tramadol-conditioned place preference (CPP) procedure assessed TRA reinforcement, after which all rats were euthanized, tissue extracted, and mRNA expression for brain-derived neurotrophic factor (Bdnf) and interleukin 1 beta (Il-1β) determined in hippocampus (Hipp), prefrontal cortex (PFC), and nucleus accumbens (NAc).

RESULTS

TRA-seeking behavior was seen in the TRA group and the 6 weeks forced exercise group. By contrast, forced exercise for 2 or 4 weeks attenuated TRA-seeking behavior. This attenuation was associated with a significant increase in Bdnf mRNA expression in the Hipp and NAc, but not the PFC. Additionally, the TRA-induced elevations in Il-1β mRNA expression were reversed by all durations of exercise in Hipp. However, only 2 and 4 weeks, but not 6 weeks, of exercise reduced elevations in PFC and NAc Il-1β expression.

CONCLUSION

Forced exercise for 2 and 4 weeks attenuates TRA-seeking behavior partially through the regulation of Bdnf and Il-1β mRNA expression.