Motor Activity Research Articles

Reliability and validity of the Turkish version of the Infant Motor Activity Log in infants with upper extremity functional asymmetry: how often and how well?

Reliability and validity of the Turkish version of the Infant Motor Activity Log in infants with upper extremity functional asymmetry: how often and how well?

Chemotherapy-Induced Neuropathy Affecting the Gastrointestinal Tract.

Cancer is a major global cause of morbidity and mortality. Survivorship is increasing, bringing new challenges. Cancer treatment, including chemotherapeutic drugs, immunotherapy, and radiotherapy, can have severe and impactful gastrointestinal side effects occurring shortly after treatment (acute toxicity) or persisting for years after treatment ends (late/chronic toxicity). The aim of this article is to review the neurotoxic effects of chemotherapy on the enteric nervous system (ENS) and the gut extrinsic innervation. These effects could contribute to the development of long-term gastrointestinal dysfunctions. Research, primarily conducted in animal models, indicates that antitumoral drugs can lead to chemotherapy-induced enteric neuropathy (CIEN). Studies, mainly performed in the myenteric plexus, show that CIEN is characterized by a reduced density of nerve cells and fibers, as well as an imbalanced representation of neuronal subpopulations or their markers, with enteric glial cells also affected. These alterations underlie changes in neuronal activity and gastrointestinal motor function. Although research on the submucosal plexus remains limited, evidence suggests that CIEN affects the entire ENS. Furthermore, scarce studies show that CIEN also occurs in humans. Moreover, emerging experimental data on chemotherapy-induced alterations in visceral sensitivity suggest that the extrinsic innervation of the gut is also affected, but this has received little attention thus far. Nevertheless, this could contribute to the development of chemotherapy-induced brain-gut axis (BGA) disorders in the long term. Cancer chemotherapy (and probably also immunotherapy and radiotherapy) seems to cause neuropathic effects on the intrinsic and extrinsic innervation of the gastrointestinal tract, with an important impact on gastrointestinal and BGA functions. This is a relatively neglected area deserving further investigation.

The critical thinking approach to tactical development in team sports: a review of the work of Jean Francis Gréhaigne

ABSTRACT Background: Critical thinking underlies tactical ability, and in the sporting context, it is known as reflective thinking that is used to make reasonable and defensible decisions in movement tasks. Critical thinking and sports tactics can then be described as analytical processes that involve solving situations in a reflective way. It is through experiences and discussions around experiences that more meaningful learning is generated (Godbout and Gréhaigne 2022). If we want to develop the tactical ability of players and, therefore, their decision-making ability, we should try to improve their critical thinking skills. Purpose: The purpose of this study was to review French Professor Jean Francis (J.F.) Gréhaigne's research on tactical development in team sports from a critical thinking perspective to enhance player decision-making. Gréhaigne, a professor in the Department of Sports Science and Physical Activity at the Institute for Teacher Education of Franche-Comté in Besancon, France, has dedicated his research career to identifying the elements associated with the teaching and pedagogy of team sports. His work is particularly noteworthy in that it proposes that critical thinking underlies tactical ability; it means that before a motor action, there must be an analysis of the situation, and this analysis must be explicit for the current moment. Method: A reflexive thematic analysis was conducted using electronic databases of research articles published before September 2021. The databases utilized were SCOPUS and Google Scholar. The search did not target any exclusive journal but focused on articles where Professor J.F. Gréhaigne was the lead or co-author, specifically related to tactical development and critical thinking in team sports. Although the search was primarily conducted in English, French works were also considered due to the author’s linguistic capabilities and the relevance of Professor Gréhaigne's contributions. A total of twenty articles were included in the documentary analysis. Results: According to the contributions of Professor J.F. Gréhaigne, it is possible to recognize that the proposals based on tactical development in team sports arose from the need, mainly, to identify a pedagogical didactic process that sought to develop analytical abilities in line with the reality of the game. Recognizing the game as a dynamic, chaotic, and uncertain system reveals that the way in which its development should be approached should be far from rigid pedagogical structures. Conclusions: Critical thinking is always essential for team sports players during the game. Pedagogical proposals should focus on developing players’ critical awareness and analytical capacity so that they can solve spontaneous situations on their own. This study is the first reflexive thematic analysis of the work developed by Professor J.F. Gréhaigne related to critical thinking and tactics in team sports. The findings of this study provide significant information and directions for the future development of tactical skills in team sports.

Macrophages excite muscle spindles with glutamate to bolster locomotion.

The stretch reflex is a fundamental component of the motor system that orchestrates the coordinated muscle contractions underlying movement. At the heart of this process lie the muscle spindles (MS), specialized receptors finely attuned to fluctuations in tension within intrafusal muscle fibres. The tension variation in the MS triggers a series of neuronal eventsincluding an initial depolarization of sensory type Ia afferents that subsequently causes the activation of motoneurons within the spinal cord1,2. This neuronal cascade culminates in the execution of muscle contraction, underscoring a presumed closed-loop mechanism between the musculoskeletal and nervous systems. By contrast, here we report the discovery of a new population of macrophages with exclusive molecular and functional signatures within the MS that express the machinery for synthesizing and releasing glutamate. Using mouse intersectional genetics with optogenetics and electrophysiology, we show that activation of MS macrophages (MSMP) drives proprioceptive sensory neuron firing on a millisecond timescale. MSMP activate spinal circuits, motor neurons and muscles by means of a glutamate-dependent mechanism that excites the MS. Furthermore, MSMP respond to neural and muscle activation by increasing the expression of glutaminase, enabling them to convert the uptakenglutamine released by myocytes during muscle contraction into glutamate. Selective silencing or depletion of MSMP in hindlimb muscles disrupted the modulation of the stretch reflex for force generation and sensory feedback correction, impairing locomotor strategies in mice. Our results have identified a new cellular component, the MSMP, that directly regulates neural activity and muscle contraction. The glutamate-mediated signalling of MSMP and their dynamic response to sensory cues introduce a new dimension to our understanding of sensation and motor action, potentially offering innovative therapeutic approaches in conditions that affect sensorimotor function.

The review of innovations and prospects for the development of physical therapy in modern medicine

Aim. To study and summarize the main modern approaches to physical therapy, namely kinesiotherapy, robotic rehabilitation system and virtual platforms; to analyze their effectiveness in different clinical settings and the problem of individualization of rehabilitation programs and the need to develop personalized approaches to patients with different types of pathologies. Materials and methods. The research materials were materials from scientific publications and thematic Internet sites. The methods of data systematization and generalization were used in the study. Results. Physical therapy is an important component of medical care, especially for patients who need to recover from injuries, surgeries, or suffer from chronic diseases of the musculoskeletal system and nervous system. Recent decades have been marked by a significant development in physical rehabilitation methods, including the use of the latest technologies and interdisciplinary approaches. Kinesiotherapy is a method of physical therapy based on the use of motor activity to restore body functions. It is one of the most widespread and scientifically proven approaches to the treatment of various pathologies. Robotic rehabilitation systems are one of the most promising areas of modern medicine. Robotic exoskeletons and rehabilitation platforms provide the ability to perform movements with a high level of control and correction, which helps to avoid incorrect exercise performance and speeds up the recovery process. Virtual reality (VR) and telemedicine allow patients to participate in rehabilitation programs in a safe and controlled environment that can be adapted to their needs. A literature review has shown that the use of a personalized rehabilitation program increases the effectiveness of a patient’s physical therapy. Conclusions. Based on the analysis, it has been found that traditional methods of kinesiotherapy remain the basis of rehabilitation programs, but their effectiveness can be significantly improved through the use of innovative technologies, such as robotic systems, virtual reality and telemedicine platforms. In addition, the combination of different physical rehabilitation methods allow achieving better results in restoring the patients’ physical functions, which is confirmed by the results of many studies. The implementation of such comprehensive approaches can reduce rehabilitation time and improve the quality of life of patient.

Experience of total hip arthroplasty in a patient with post-traumatic aseptic necrosis of the femoral head

A hip fracture is a common injury in old age. It can be noted that the number of fractures is several times higher in women compared to men. Without surgical treatment, this pathology is highly likely to lead to complications and death of the patient within a year. High mortality rates in elderly people who have sustained a hip fracture can be attributed to various reasons. Due to prolonged forced bed rest in such patients, the risk of developing respiratory and cardiovascular complications, thrombosis, bleeding and infection significantly increases. In modern clinical practice, all fractures of the femoral neck are the reason for surgical intervention, according to vital indications. The only exception is the general severe condition of the patient in case of disruption of the normal functioning of the cardiovascular and respiratory systems, multiple organ failure and oncological diseases in the stage of decompensation.Purpose of a study: to demonstrate successful total arthroplasty of the left hip joint in elderly patient with posttraumatic avascular necrosis.Data from the medical documentation of the trauma hospital, data from instrumental research and the results of dynamic observation were used to write the article. The results were obtained using the equipment of the Center for Collective Use of Scientific Equipment of Tambov State University named after G.R. Derzhavin.As a result of total hip arthroplasty, the function of the patient's limb was restored.Conclusion. Total arthroplasty is an effective treatment method for patients with post-traumatic changes in the hip joint, allowing to restore the patient’s motor activity and prevent the development of hypostatic complications.

Fractal motor activity during wakefulness and sleep: a window into depression recency and symptom recurrence

Abstract Background Motor activity fluctuations in healthy adults exhibit fractal patterns characterized by consistent temporal correlations across wide-ranging time scales. However, these patterns are disrupted by aging and psychiatric conditions. This study aims to investigate how fractal patterns vary across the sleep–wake cycle, differ based on individuals' recency of depression diagnosis, and change before and after a depressive episode. Methods Using actigraphy from two cohorts (n = 378), we examined fractal motor activity patterns both between individuals without depression and with varying recencies of depression and within individuals before and after depressive symptom recurrence. To evaluate fractal patterns, we quantified temporal correlations in motor activity fluctuations across different time scales using a scaling exponent, α. Linear mixed models were utilized to assess the influence of the sleep–wake cycle, (recency of) depression, and their interaction on α. Results Fractal activity patterns in all individuals varied across the sleep–wake cycle, showing stronger temporal correlations during wakefulness (larger α = 1.035 ± 0.003) and more random activity fluctuations during sleep (smaller α = 0.784 ± 0.004, p < 0.001). This sleep–wake difference was reduced in recently depressed individuals (1–6 months), leading to larger α during sleep (0.836 ± 0.017), compared to currently depressed (0.781 ± 0.018, p = 0.006), remitted (0.776 ± 0.014, p < 0.001), and never-depressed individuals (0.773 ± 0.016, p < 0.001). Moreover, remitted individuals who experienced depressive symptom recurrence during antidepressant tapering exhibited a larger α during sleep after the symptom onset as compared to before (after: α = 0.703 ± 0.022; before: α = 0.680 ± 0.022; p < 0.001). Conclusions These findings suggest a link between fractal motor activity patterns during sleep and depressive symptom recurrence in remitted individuals and those with recent depression.

Histaminergic Innervation of the Ventral Anterior Thalamic Nucleus Alleviates Motor Deficits in a 6-OHDA-Induced Rat Model of Parkinson’s Disease

AbstractThe ventral anterior (VA) nucleus of the thalamus is a major target of the basal ganglia and is closely associated with the pathogenesis of Parkinson’s disease (PD). Notably, the VA receives direct innervation from the hypothalamic histaminergic system. However, its role in PD remains unknown. Here, we assessed the contribution of histamine to VA neuronal activity and PD motor deficits. Functional magnetic resonance imaging showed reduced VA activity in PD patients. Optogenetic activation of VA neurons or histaminergic afferents significantly alleviated motor deficits in 6-OHDA-induced PD rats. Furthermore, histamine excited VA neurons via H1 and H2 receptors and their coupled hyperpolarization-activated cyclic nucleotide-gated channels, inward-rectifier K+ channels, or Ca2+-activated K+ channels. These results demonstrate that histaminergic afferents actively compensate for Parkinsonian motor deficits by biasing VA activity. These findings suggest that targeting VA histamine receptors and downstream ion channels may be a potential therapeutic strategy for PD motor dysfunction.

Laryngeal Vibrotactile Stimulation Is Feasible, Acceptable To People With Unexplained Chronic Cough.

Unexplained chronic cough (UCC) is common and has significant impacts on quality of life. Ongoing cough can sensitize the larynx, increasing the urge to cough and perpetuating the cycle of chronic cough. Vibrotactile stimulation (VTS) of the larynx is a noninvasive stimulation technique that can modulate laryngeal somatosensory and motor activity. Study objectives were to assess feasibility and acceptability of VTS use by people with UCC. Secondarily, changes in cough-related quality of life measures were assessed. Adults with UCC recorded cough measures at baseline and after completing 2 weeks of daily VTS. Feasibility and acceptability were assessed through participant-reported device use and structured feedback. Cough-related quality of life measures were the Leicester Cough Questionnaire (LCQ) and the Newcastle Laryngeal Hypersensitivity Questionnaire (NLHQ). Nineteen adults participated, with mean age 67 years and cough duration 130 months. Notably, 93% of planned VTS sessions were logged, 94% of participants found the device comfortable to wear, 89% found it easy to operate and 79% would recommend it to others. Pre-post LCQ change achieved a minimal important difference (MID) (mean 1.3 [SD 2.4, p = 0.015]). NLHQ scores improved, but did not reach an MID. Laryngeal VTS use was feasible and acceptable for use by patients with UCC and was associated with a meaningful improvement in cough-related quality of life. Future studies will include VTS dose refinement and the inclusion of a comparison arm to further assess the potential for laryngeal VTS as a novel treatment modality for UCC. 4 Laryngoscope, 134:5010-5014, 2024.

Treatment Algorithms for Continuous Low-Level Heat Wrap Therapy for the Management of Musculoskeletal Pain: An Italian Position Paper.

Musculoskeletal pain (MSP), which impacts bones, muscles, tendons, and ligaments, is a substantial worldwide pain disorder, characterized by muscle soreness, fatigue, inflammation, muscle spasms, sleep disruptions, and functional limitations. MSP is predominantly managed within the primary care setting. Recent consensus recognizes that heat therapy (HT) may provide potential benefits, especially in treating chronic MSP. To develop shared algorithms for the treatment of MSP through local superficial HT (SHT) using continuous low-level heat wrap therapy, a four-member board of experts was designated. Three anatomical sites have been deemed of particular interest regarding potential response to exogenous SHT. Neck and shoulder pain are commonly attributed to traumatic experiences, muscle spasms, postural defects, or poor posture as common potential causes. HT may be helpful for painful contractures, although treatment should be limited in duration to prevent instability. Low back pain, the leading cause of disability, may have either specific or non-specific etiology. SHT, physical therapy, instrumental therapy, manual therapy, therapeutic exercise, motor activity, and trunk orthoses are all potential treatment options. SHT should be considered in chronic degenerative disc disease, non-specific LBP with muscle spasm or contracture, postural and overuse myalgia, and osteoarthritis (OA), excluding the inflammatory phase. Assessment of knee pain includes both a review of the patient's medical history and a careful physical examination. SHT of the knee should be considered in case of muscle spasms, overuse pathology, early OA, and indirect muscle lesions. Patients who receive SHT may experience a reduction in pain, restoration of muscle strength, loosening of stiffness, and an overall improvement in their quality of life. This expert opinion proposes shared algorithms for MSP treatment via local SHT with the aiming to provide practical guidance on its proper application, highlighting specific potentialities as well as contraindications.

D-Amphetamine and Feeding States Cohesively Affect Locomotion and Motor Neuron Response in Zebrafish Larvae.

Amphetamine (AMPH) increases locomotor activities in animals, and the locomotor response to AMPH is further modulated by caloric deficits such as food deprivation and restriction. The increment in locomotor activity regulated by AMPH-caloric deficit concomitance can be further modulated by varying feeding schedules (e.g., acute and chronic food deprivation and acute feeding after chronic food deprivation). However, the effects of different feeding schedules on AMPH-induced locomotor activity are yet to be explicated. Here, we have explored the stimulatory responses of acutely administered D-amphetamine in locomotion under systematically varying feeding states (fed/sated and food deprivation) and schedules (chronic and acute) in zebrafish larvae. We exposed wild-type and transgenic [Tg(mnx1:GCaMP5)] zebrafish larvae to 0.7µM concentration of AMPH and measured swimming activity and spinal motor neuron activity in vivo in real time. The analysis involved time-elapsed and cumulative manner pre- and post-AMPH treatment in four different caloric states including acute and chronic schedules of feeding and hunger. Both locomotor and motor neuron activities were compared in all four states in both fish lines. Our results show that locomotion and motor neuron activity increased in both chronic and acute food deprivation post-AMPH treatment cumulatively. A steady increase in locomotion was observed in acute food deprivation compared to an immediate abrupt increase in chronic food-deprivation state. The ad libitum-fed larvae exhibited a moderate increase both in locomotion and motor neuron activity. Conversely to all other caloric states, food-sated (acute feeding after chronic food deprivation) larvae moved moderately less and exhibited a mild decrease in motor neuron activity after AMPH treatment. These results reveal the importance of cohesive effects of feeding schedule and AMPH treatment by revealing the changes in stimulatory characteristics of AMPH on locomotion and motor neuron activity in acute and chronic feeding states.

The Role of Ocimene in Decreasing α-Synuclein Aggregation using Rotenone-induced Rat Model.

Parkinson's disease is defined by the loss of dopaminergic neurons in the midbrain of substantia nigra associated with Lewy bodies. The precise mechanism is not yet entirely understood. The study aims to determine whether ocimene has antiparkinsonian activity by reducing α-Synuclein aggregation levels in the brains of rotenone-induced rat models. 36 male rats were used for six groups, with six animals in each group. Vehicle, control (rotenone, 2.5 mg/kg, i.p), standard (L-Dopa, 10 mg/kg, i.p), Test drug of low dose (66.66 mg/kg, i.p), medium dose (100 mg/kg, i.p), and high dose (200 mg/kg, i.p) were administered to the rats. The open field, actophotometer, hanging wire, and catalepsy tests were used to assess the rat's motor performance. The expressions of biomarkers such as AchE, D2 Receptor, and α- Synuclein were evaluated, and their level of expression in the brain samples was checked using ELISA. Histopathological analysis was also carried out to determine the degree of neuron degeneration in the brain samples. The open field test showed significant anxiety levels, whereas test groups showed fewer anxiety levels but increased motor activity. The biochemical tests revealed that rotenonetreated rats had higher levels of AchE, but ocimene-treated rats had a significant decrease in AchE levels. The test drug-treated rats also expressed high levels of D2 receptors. In ocimenetreated rats, α-Synuclein aggregation was reduced, however, in rotenone-treated rats' brain samples, higher clumps of α-Synuclein were observed. Ocimene has neuroprotective properties. As a result, this essential oil might be helpful as a therapeutic treatment for Parkinson's disease.

Lycium barbarum oligosaccharide-derived carbon quantum dots inhibit glial scar formation while promoting neuronal differentiation of neural stem cells

Overexpression of glial fibrillary acidic protein (GFAP) in activated astrocytes following spinal cord injury is closely associated with glial scar formation, which harms axonal regrowth. In this study, we prepared ultrasmall cationic carbon quantum dots (CQDs) via one-step hydrothermal carbonization. Lycium barbarum oligosaccharides were used as the carbon source for the first time, and polyetherimide (PEI) and ethylenediamine (ED) were used as cationic reagents. Interestingly, the resultant CQDs show the bioactivity of specifically inhibiting GFAP protein expression, while promoting neuronal marker expression in neural stem cells (NSCs). Furthermore, CQDs together with NSCs can remarkably improve the motor activity of animals after implantation into the transection lesion of the rat spinal cord. Histological analysis confirmed that CQDs can enhance neuronal differentiation of NSCs while inhibiting glial scar formation in vivo. Altogether, this study represents the first report of producing CQDs from oligosaccharides and investigating their impact on NSCs differentiation, thus providing a paradigm for exploring the bioactivity of quantum dots.

Morningness–Eveningness Preference and Motor Wake–Sleep Inertia in Adolescents

The aim of the present work was to analyze possible differences in the wake–sleep and sleep–wake transition in relation to adolescents’ circadian preference using actigraphy. Overall, 729 participants were enrolled in the research and 443 of them wore actigraphs on the non-dominant wrist for at least three nights. According to the reduced Morningness–Eveningness Questionnaire for Children and Adolescents cut-off scores, 61 participants belonged to the evening-type category, while 38 participants belonged to the morning-type. We extracted the motor activity counts, minute-by-minute, during the wake–sleep and sleep–wake transitions, to depict the motor wake inertia and motor sleep inertia, respectively. We adopted the functional linear modeling statistical framework to examine the changes in both transitions according to chronotype. Overall, the results show a significantly higher motor wake inertia and lower motor sleep inertia in morning compared to evening types.

A first-in-human application of OPM-MEG for localizing motor activity area: Compared to functional MRI

BackgroundAccurately localizing brain motor areas is vital for protecting motor function during neurosurgical procedures. Magnetoencephalography (MEG) based on optically pumped magnetometer (OPM) improves the availability of MEG in clinical applications. The aim of this study is to evaluate the availability, accuracy and precision of “OPM-MEG” for localizing motor areas in brain tumor patients and healthy individuals. MethodsParticipants were enrolled and subjected to primary motor area localization by both 3T-fMRI and 128-channel OPM-MEG examinations. The localization accuracy (ability of mapping on the anatomical location) and precision (activation signal centralization) were compared between the two methods, and accuracy was further validated by intraoperative direct cortical electrical stimulation (DCS) on the localized area with assistance of neuro-navigation system. ResultA total of 12 participants (7 brain tumor patients and 5 healthy individuals) were enrolled and all had successful localization for motor areas by both methods. The average time of OPM-MEG examination for each limb function was approximately 9 min. The localizations by both methods mainly covered the anatomical location of primary motor cortex and were partially overlapped. The motor activation signal identified by OPM-MEG was more centralized than fMRI did. The centroid of motor area localized by the OPM-MEG deviated from it by fMRI, with a mean distance of 19.7 mm and 27.48 mm for hand or foot localization, respectively. Furthermore, the OPM-MEG centroid for hand movement successfully triggered corresponding hand response by DCS. ConclusionsIn this first-in-human study exploring the potential of OPM-MEG in functional localization of motor areas, we revealed its availability and reliability in mapping motor areas, demonstrating it as a promising tool in assisting neurosurgical practice and neuroscience research.

Decoupling of motor cortex to movement in Parkinson's dyskinesia rescued by sub-anaesthetic ketamine.

Gamma band and single-unit neural activity in primary motor cortex (M1) are involved in the control of movement. This activity is disrupted in Parkinson's disease (PD) and levodopa-induced dyskinesia (LID), a debilitating consequence of dopamine replacement therapy for PD. Physiological features of LID include pathological narrowband gamma oscillations, finely tuned gamma (FTG), and altered M1 firing activity. Since most studies characterize LID through visual scoring, little is known about the relationships between ongoing dyskinetic movements, gamma, and neuronal activity at fast (sub-second) and slow (seconds) timescales. Here, we investigate how motor cortex activity changes with movement at multiple timescales in animal models of PD and LID. Furthermore, sub-anesthetic ketamine has emerged as a possible therapy for LID. How ketamine may reduce LID is not fully understood. Consequently, we investigate how ketamine affects the relationship between motor cortex activity and movement. To investigate these questions, local-field and single-unit activity from >3000 motor cortex neurons was acquired using a standard model of PD/LID (n = 10 male rats). Data in LID and sham animals was acquired following levodopa (L-DOPA; 12 mg/kg, i.p.) and ketamine (20 mg/kg, i.p.) administration. Movement was assessed using traditional abnormal involuntary movements (AIMs) scores and head-mounted inertial sensors sampled at 200 Hz. While correlations between movement, gamma, and single-unit activity were high in all animals during control conditions, correlations decreased considerably in animal models of LID following L-DOPA administration. This suggests that M1 can become functionally decoupled from ongoing movements in LID. Interestingly, this effect was observed in both the dopamine depleted and non-depleted hemispheres. Ketamine disrupted FTG, decreased LID, and moderately increased single-unit correlations to movement during LID. Ketamine, however, did not enhance the correlation between gamma-band activity and movement. Finally, ketamine exerted a selective effect on neuronal interactions and ensemble activity in LID animals. Specifically, analysis of cell-pair firing-rate correlations showed that ketamine induced a distinct neural ensemble state in LID by reorganizing the pattern of cell-pair interactions. These findings provide insight into the role that motor cortex neurons and gamma-band activity play during healthy movement and LID. Results suggest that primary motor cortex does not directly trigger specific dyskinetic movements during LID but, instead, dysregulated motor cortex activity may permit aberrant movements to spontaneously emerge in downstream circuits. These data further support the anti-dyskinetic properties of ketamine and suggest that ketamine acts to reduce LID by disrupting pathological interactions between motor cortex neurons during dyskinesia.

Exploring the Impact of Semaglutide on Cognitive Function and Anxiety-Related Behaviors in a Murine Model of Alzheimer’s Disease

Background: Alzheimer’s disease (AD), the most prevalent form of dementia, is characterized by progressive cognitive decline and behavioral disturbances, with an increasing incidence as the global population ages. This study investigates the effects of semaglutide (SEM), a glucagon-like peptide-1 analog, on cognitive function and anxiety-like behavior in a transgenic murine model of AD. Methods: 20 mice were randomly distributed into the following groups (n = 5): (WT + VEH) group: C57BL/6J + saline, (WT + SEM) group: C57BL/6J + semaglutide, (AD + VEH) group: AD + saline, (AD + SEM) group: AD + semaglutide. The animals underwent a four-week treatment, during which we monitored blood glucose levels, body weight, and responses in an open field test, novel object recognition test, social chamber test, and 0-maze test. Results: Post-treatment, SEM significantly reduced blood glucose levels in AD mice, aligning them with those of wild-type controls. Cognitive assessments indicated an improvement in the investigation index for SEM-treated mice compared to those receiving a vehicle, suggesting cognitive benefits. Although SEM did not significantly enhance motor and exploratory activities, it displayed a potential anxiolytic effect, particularly evident in the combined anxiety index, with notable differences observed before and after treatment in the AD group. Conclusions: The findings of this pilot study suggest that SEM may play a dual role in managing AD by improving glycemic control and potentially enhancing cognitive function. As the landscape of AD treatment evolves, the comprehensive approach of utilizing SEM could pave the way for innovative interventions targeting the complex interplay of metabolic and cognitive dysfunctions in this challenging neurodegenerative disorder.

Effect of northwestern photoperiod and exogenous melatonin on the psychoemotional state of the Syrian hamsters (Mesocricetus auratus)

Background. Among the environmental factors that influence the increase in the frequency of occurrence of psychoemotional states, great importance is attributed to the light conditions. However, the mechanisms of behaviour regulation in the mammals in non-standard light conditions and the role of melatonin in this process have not been fully studied.The aim of the study. To assess the effects of specific northern light conditions and melatonin on the behavior of Mesocricetus auratus.Methods. The animals were divided into 4 groups: LD (control), NL (northern light conditions), and LD + mel and NL + mel (melatonin, 100 μg/animal). The study of behavioral reactions, the level of emotional and phobic anxiety state of animals was carried out in the “Open field” and “Dark chamber with holes” installations.Results. Keeping M. auratus in NL had a negative effect on their behavior – a decrease in motor activity (horizontal and vertical) and the “hole-exploratory behavior”, an increase in the number of freezing and grooming reactions and the time of the first peeking out of the upper hole were revealed. It was shown that melatonin contributed to an increase in exploratory activity and a decrease in the number of anxiety acts in NL + mel group compared to NL group; the opposite effect of the hormone on these parameters was observed in LD + mel group.Conclusion. The obtained results indicate the important role of photoperiod and melatonin in regulating the behavior of seasonally breeding species.

Cerebrolysin Induces Motor Recovery Along with Plastic Changes in Motoneurons and an Increase in GAP43 Protein in the Ventral Spinal Cord Following a Kainic Acid Excitotoxic Lesion in the Rat Motor Cortex.

Lesions in the motor cortex induced by contusions or pathological insults can exert the degeneration of afferent neurons lying distal to these lesions. Axon degeneration and demyelination are hallmarks of several diseases sharing pathophysiological and clinical characteristics. These conditions are very disabling due to the disruption of motor abilities, with lesions that affect this area proving to be a therapeutic challenge, which has driven increasing efforts to search for treatments. Cerebrolysin (CBL) contains a mix of pig brain-derived peptides with activity similar to neurotrophic factors. Here, the effect of cerebrolysin administration on the motor impairment produced by kainic acid (KA) lesion of the motor cortex was evaluated in Sprague-Dawley female rats (n = 27), defining its effect on motoneurons dendritic tree changes, dendritic spine density and GAP43 presence in the ventral thoracolumbar regions of the spinal cord. Ten days after the KA lesion of the motor cortex, rats were administered cerebrolysin, and their motor performance was evaluated using the "Basso, Beattie, and Bresnahan" (BBB) and Bederson scores. Cerebrolysin administration improved motor activity according to the BBB and Bederson scales, along with increased dendritic intersections and dendritic spine density on motoneurons. There was also a significant increase in GAP43 protein, suggesting that CBL may promote plastic changes through this protein, among others. Hence, this study proposes that cerebrolysin could promote motor recovery following motor cortex lesions by driving neuronal changes and dendritic spine plasticity on motoneurons and an increase in GAP43 protein, along with other mechanisms.

The Importance of Genetic Background and Neurotransmission in the Pathogenesis of the Co-Occurrence of Sleep Bruxism and Sleep-Disordered Breathing—Review of a New Perspective

Sleep bruxism (SB) and sleep-disordered breathing (SDB) are two prevalent conditions that significantly impact overall health. Studies suggest that up to 49.7% of individuals with SDB also exhibit symptoms of SB. This review aims to provide a comprehensive analysis of the role of genetic background and neurotransmission in the pathogenesis of the co-occurrence of SB and SDB. It seeks to synthesize current knowledge, highlight gaps in the existing literature, and propose a new perspective that integrates genetic and neurobiological factors. This review shows that both SB and SDB may be influenced by a combination of genetic, neurochemical, and environmental factors that contribute to their shared pathophysiology. The key neurotransmitters—dopamine, serotonin, and GABA—may play a significant role in their co-occurrence by regulating motor activity, sleep architecture, and respiratory control. Understanding genetic and neurochemical mechanisms may allow for more precise diagnostic tools and more personalized treatment approaches regarding SB and SDB. Clinically, there is a need for interdisciplinary collaboration between sleep specialists, dentists, neurologists, and geneticists. There is also a need to conduct large-scale genetic studies, coupled with neuroimaging and neurophysiological research, uncovering additional insights into the shared mechanisms of SB and SDB.