In vitro functional assays to assess the reciprocal interplay between tumor cells and macrophages.

Tumor-associated macrophages (TAMs) are integral components of the tumor microenvironment. They are involved in various aspects of tumor cell biology, driving pathological processes such as tumor cell proliferation, metastasis, immunosuppression, and resistance to therapy. TAMs exert their tumorigenic effects by secreting growth factors, cytokines/chemokines, metabolites, and other soluble bioactive molecules. These mediators directly promote tumor cell proliferation and modulate interactions with immune and stromal cells, facilitating further tumor growth. As research into therapies targeting TAMs intensifies, there is a growing need for reliable methods to comprehend the impact of TAMs on cancer progression and to validate novel therapeutics directed at TAMs. The traditional "M1-M2" macrophage classification based on transcriptional profiles of TAMs is not only too simplistic to describe their physiological roles, it also does not explain differences observed between mouse and human macrophages. In this context, methods that assess how TAMs influence tumor or immune cells, either through direct contact or the release of soluble factors, offer a more promising approach. We describe here comprehensive protocols for in vitro functional assays to study TAMs, specifically regarding their impact on the growth of lung cancer cells. We have applied these methods to both mouse and human macrophages, achieving similar outcomes in promoting the proliferation of cancer cells. This methodology can serve as a standardized approach for testing novel therapeutic approaches, targeting TAMs with novel immunotherapeutic compounds, or utilizing gene-editing techniques. Taken together, the described methodology may contribute to our understanding of complex macrophage-tumor interactions and support the development of innovative therapeutic strategies.

The Impact of Treadmill Training on Tissue Integrity, Axon Growth, and Astrocyte Modulation.

Spinal cord injury (SCI) presents a complex challenge in neurorehabilitation, demanding innovative therapeutic strategies to facilitate functional recovery. This study investigates the effects of treadmill training on SCI recovery, emphasizing motor function enhancement, neural tissue preservation, and axonal growth. Our research, conducted on a rat model, demonstrates that controlled treadmill exercises significantly improve motor functions post-SCI, as evidenced by improved scores on the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale and enhanced electromyography readings. Notably, the training facilitates the preservation of spinal cord tissue, effectively reducing secondary damage and promoting the maintenance of neural fibers in the injured area. A key finding is the significant stimulation of axonal growth around the injury epicenter in trained rats, marked by increased growth-associated protein 43 (GAP43) expression. Despite these advancements, the study notes a limited impact of treadmill training on motoneuron adaptation and highlights minimal changes in the astrocyte and neuron-glial antigen 2 (NG2) response. This suggests that, while treadmill training is instrumental in functional improvements post-SCI, its influence on certain neural cell types and glial populations is constrained.

Safety and Efficacy of Intravenous and Intrathecal Delivery of AAV9-Mediated ARSA in Minipigs.

Metachromatic leukodystrophy (MLD) is a hereditary neurodegenerative disease characterized by demyelination and motor and cognitive impairments due to deficiencies of the lysosomal enzyme arylsulfatase A (ARSA) or the saposin B activator protein (SapB). Current treatments are limited; however, gene therapy using adeno-associated virus (AAV) vectors for ARSA delivery has shown promising results. The main challenges for MLD gene therapy include optimizing the AAV dosage, selecting the most effective serotype, and determining the best route of administration for ARSA delivery into the central nervous system. This study aims to evaluate the safety and efficacy of AAV serotype 9 encoding ARSA (AAV9-ARSA) gene therapy when administered intravenously or intrathecally in minipigs, a large animal model with anatomical and physiological similarities to humans. By comparing these two administration methods, this study contributes to the understanding of how to improve the effectiveness of MLD gene therapy and offers valuable insights for future clinical applications.

Intrathecal Injection of Autologous Mesenchymal Stem-Cell-Derived Extracellular Vesicles in Spinal Cord Injury: A Feasibility Study in Pigs.

Spinal cord injury (SCI) remains one of the current medical and social problems, as it causes deep disability in patients. The use of mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) is one strategy for stimulating the post-traumatic recovery of the structure and function of the spinal cord. Here, we chose an optimal method for obtaining cytochalasin B-induced EVs, including steps with active vortex mixing for 60 s and subsequent filtration to remove nuclei and disorganized inclusions. The therapeutic potential of repeated intrathecal injection of autologous MSC-derived EVs in the subacute period of pig contused SCI was also evaluated for the first time. In this study, we observed the partial restoration of locomotor activity by stimulating the remyelination of axons and timely reperfusion of nervous tissue.

Severity- and Time-Dependent Activation of Microglia in Spinal Cord Injury.

A spinal cord injury (SCI) initiates a number of cascades of biochemical reactions and intercellular interactions, the outcome of which determines the regenerative potential of the nervous tissue and opens up capacities for preserving its functions. The key elements of the above-mentioned processes are microglia. Many assumptions have been put forward, and the first evidence has been obtained, suggesting that, depending on the severity of SCI and the post-traumatic period, microglia behave differently. In this regard, we conducted a study to assess the microglia behavior in the model of mild, moderate and severe SCI in vitro for various post-traumatic periods. We reported for the first time that microglia make a significant contribution to both anti- and pro-inflammatory patterns for a prolonged period after severe SCI (60 dpi), while reduced severities of SCI do not lead to prolonged activation of microglia. The study also revealed the following trend: the greater the severity of the SCI, the lower the proliferative and phagocytic activity of microglia, which is true for all post-traumatic periods of SCI.

Genetically Engineered Artificial Microvesicles Carrying Nerve Growth Factor Restrains the Progression of Autoimmune Encephalomyelitis in an Experimental Mouse Model.

Multiple sclerosis (MS) is an incurable, progressive chronic autoimmune demyelinating disease. Therapy for MS is based on slowing down the processes of neurodegeneration and suppressing the immune system of patients. MS is accompanied by inflammation, axon-degeneration and neurogliosis in the central nervous system. One of the directions for a new effective treatment for MS is cellular, subcellular, as well as gene therapy. We investigated the therapeutic potential of adipose mesenchymal stem cell (ADMSC) derived, cytochalasin B induced artificial microvesicles (MVs) expressing nerve growth factor (NGF) on a mouse model of multiple sclerosis experimental autoimmune encephalomyelitis (EAE). These ADMSC-MVs-NGF were tested using histological, immunocytochemical and molecular genetic methods after being injected into the tail vein of animals on the 14th and 21st days post EAE induction. ADMSC-MVs-NGF contained the target protein inside the cytoplasm. Their injection into the caudal vein led to a significant decrease in neurogliosis at the 14th and 21st days post EAE induction. Artificial ADMSC-MVs-NGF stimulate axon regeneration and can modulate gliosis in the EAE model.

Extracellular Matrix in Neural Plasticity and Regeneration.

The extracellular matrix (ECM) is a fundamental component of biological tissues. The ECM in the central nervous system (CNS) is unique in both composition and function. Functions such as learning, memory, synaptogenesis, and plasticity are regulated by numerous ECM molecules. The neural ECM acts as a non-specific physical barrier that modulates neuronal plasticity and axon regeneration. There are two specialized types of ECM in the CNS, diffuse perisynaptic ECM and condensed ECM, which selectively surround the perikaryon and initial part of dendritic trees in subtypes of neurons, forming perineuronal nets. This review presents the current knowledge about the role of important neuronal ECM molecules in maintaining the basic functions of a neuron, including electrogenesis and the ability to form neural circuits. The review mainly focuses on the role of ECM components that participate in the control of key events such as cell survival, axonal growth, and synaptic remodeling. Particular attention is drawn to the numerous molecular partners of the main ECM components. These regulatory molecules are integrated into the cell membrane or disposed into the matrix itself in solid or soluble form. The interaction of the main matrix components with molecular partners seems essential in molecular mechanisms controlling neuronal functions. Special attention is paid to the chondroitin sulfate proteoglycan 4, type 1 transmembrane protein, neural-glial antigen 2 (NG2/CSPG4), whose cleaved extracellular domain is such a molecular partner that it not only acts directly on neural and vascular cells, but also exerts its influence indirectly by binding to resident ECM molecules.

The Study of Cerebrospinal Fluid microRNAs in Spinal Cord Injury and Neurodegenerative Diseases: Methodological Problems and Possible Solutions.

Despite extensive research on neurological disorders, unanswered questions remain regarding the molecular mechanisms underpinning the course of these diseases, and the search continues for effective biomarkers for early diagnosis, prognosis, or therapeutic intervention. These questions are especially acute in the study of spinal cord injury (SCI) and neurodegenerative diseases. It is believed that the changes in gene expression associated with processes triggered by neurological disorders are the result of post-transcriptional gene regulation. microRNAs (miRNAs) are key regulators of post-transcriptional gene expression and, as such, are often looked to in the search for effective biomarkers. We propose that cerebrospinal fluid (CSF) is potentially a source of biomarkers since it is in direct contact with the central nervous system and therefore may contain biomarkers indicating neurodegeneration or damage to the brain and spinal cord. However, since the abundance of miRNAs in CSF is low, their isolation and detection is technically difficult. In this review, we evaluate the findings of recent studies of CSF miRNAs as biomarkers of spinal cord injury (SCI) and neurodegenerative diseases. We also summarize the current knowledge concerning the methods of studying miRNA in CSF, including RNA isolation and normalization of the data, highlighting the caveats of these approaches and possible solutions.

Improving Culture Conditions, Proliferation, and Migration of Porcine Mesenchymal Stem Cells on Spinal Cord Contusion Injury Model in vitro.

Adipose tissue-derived mesenchymal stem cells (AD-MSCs) are promising for cell therapy in spinal cord injury (SCI). The pig is one of the most approximate models of many human diseases, including SCI. In our study, we selected the optimal conditions for the culture of porcine AD-MSCs and developed an in vitro SCI model based on the culture of cells in injured spinal cord extracts (SCE) 3 days and 6 weeks after SCI. We show that Dulbecco's Modified Eagle Medium (DMEM) with 20% serum content, supplemented with a combination of 5 mM L-ascorbate-2-phosphate and nonessential amino acids, stimulated a typical fibroblast-like morphology and high proliferation of porcine AD-MSCs. SCE caused a higher proliferation of porcine AD-MSCs compared with extracts from an intact spinal cord. The optimal proliferating effect was achieved using rostral 3 days SCE, and proliferation was lower in caudal and central SCE. Porcine AD-MSCs migration to the 3 days and 6 weeks SCE was higher than to an intact one and preferred the rostral SCE, avoiding central and caudal SCE. We also studied 13 cytokines contained in SCE but did not observe any definite relationship between some analyte concentrations and a change in the behavior of AD-MSCs.

Electrophysiology Methods for Assessing of Neurodegenerative and Post-Traumatic Processes as Applied to Translational Research.

Electrophysiological studies have long established themselves as reliable methods for assessing the functional state of the brain and spinal cord, the degree of neurodegeneration, and evaluating the effectiveness of therapy. In addition, they can be used to diagnose, predict functional outcomes, and test the effectiveness of therapeutic and rehabilitation programs not only in clinical settings, but also at the preclinical level. Considering the urgent need to develop potential stimulators of neuroregeneration, it seems relevant to obtain objective data when modeling neurological diseases in animals. Thus, in the context of the application of electrophysiological methods, not only the comparison of the basic characteristics of bioelectrical activity of the brain and spinal cord in humans and animals, but also their changes against the background of neurodegenerative and post-traumatic processes are of particular importance. In light of the above, this review will contribute to a better understanding of the results of electrophysiological assessment in neurodegenerative and post-traumatic processes as well as the possibility of translating these methods from model animals to humans.

NF-κB and JAK/STAT Signaling Pathways as Crucial Regulators of Neuroinflammation and Astrocyte Modulation in Spinal Cord Injury.

Spinal cord injury (SCI) leads to significant functional impairments below the level of the injury, and astrocytes play a crucial role in the pathophysiology of SCI. Astrocytes undergo changes and form a glial scar after SCI, which has traditionally been viewed as a barrier to axonal regeneration and functional recovery. Astrocytes activate intracellular signaling pathways, including nuclear factor κB (NF-κB) and Janus kinase-signal transducers and activators of transcription (JAK/STAT), in response to external stimuli. NF-κB and STAT3 are transcription factors that play a pivotal role in initiating gene expression related to astrogliosis. The JAK/STAT signaling pathway is essential for managing secondary damage and facilitating recovery processes post-SCI: inflammation, glial scar formation, and astrocyte survival. NF-κB activation in astrocytes leads to the production of pro-inflammatory factors by astrocytes. NF-κB and STAT3 signaling pathways are interconnected: NF-κB activation in astrocytes leads to the release of interleukin-6 (IL-6), which interacts with the IL-6 receptor and initiates STAT3 activation. By modulating astrocyte responses, these pathways offer promising avenues for enhancing recovery outcomes, illustrating the crucial need for further investigation into their mechanisms and therapeutic applications in SCI treatment.

Electrospinning Approach for Preparing Nanostructured Scaffolds for Stem Cell Seeding and/or Implantation in Neurotrauma.

Preparation of highly porous biocompatible and bioresorbable nerve conduit or scaffold by electrospinning based on synthetic polycaprolactone with a molecular weight of 80 kDa (PCL 80 kDa) has significance in the context of regenerative medicine with special emphasis on their application in neurotrauma. PCL conduits/scaffolds serving as a support structure for seeded stem cells show promising regenerative potential to promote functional recovery and tissue regeneration in models of neurotrauma. Here we describe a standard protocol for the production of conduits by electrospinning at high field-forming voltages (24kB) using a 6% solution of PCL 80 kDa in a chloroform/methanol mixture.

Astrocytes in Spinal Cord Injury: Current Opportunities and Prospects for Directional Polarization.

Activation of astrocytes during spinal cord injury (SCI) is accompanied by changes in their morphology and functional activity, possibly having severity-, localization-, and time-dependent features. The understanding of the role of reactive astrocytes has undergone significant changes over the last decades, and new data are still emerging to assess the diversity of functional manifestations of reactive cells. This review discusses the current understanding of astrocyte behavior, possible manifestations of their negative and positive roles in SCI, and the prospects for using various methods of directed polarization of astrocytes to improve post-traumatic outcomes. Despite the existing difficulties regarding the disclosure of the complex cascade of molecular changes of reactive astrocytes in different posttraumatic periods, researchers do not give up hope for the development of astrocyte-targeted methods that could reduce the severity of secondary injury by regulating the negative effects of these cells.

Eating disorder in children: Impact on quality of life, with a spotlight on autism spectrum disorder.

Eating behavior, which includes eating habits and preferences, frequency of eating, and other features related to diet, is a major characteristic not only of a person's nutritional status, but also of health in general. In recent years, the prevalence of eating disorders in children has tended to increase; they also require cross-system approaches in diagnosis by a variety of specialists and correction requires appropriate selection of optimal methods. Maladaptive eating attitudes formed at an early age can contribute to the formation of eating disorders, which can lead to or worsen various neuropsychiatric diseases, digestive diseases, and other related conditions. In children with autism spectrum disorder (ASD), eating disorders often appear earlier than other major symptoms of the condition. However, the clinical manifestations of eating disorders in children with ASD are varied and differ in severity and duration, whereas these disorders in neurotypical children might present as short-lived and may not lead to serious consequences. Nevertheless, cases of progressive eating disorders accompanied by a child presenting as under- or overweight and/or with macronutrient and micronutrient deficiencies cannot be excluded. Given the high prevalence of eating disorders in children, many researchers have highlighted the lack of a valid and universally accepted instruments to assess atypical eating behaviors in this population. Therefore, in this review, we wanted to highlight the problems and causes of eating disorders in children, and also to analyze the existing approaches to the validation of these problems, taking into account the existing behavioral features in children with ASD.

Comparative Analysis of Cytokine Profiles in Cerebrospinal Fluid and Blood Serum in Patients with Acute and Subacute Spinal Cord Injury.

BACKGROUND: Cytokines are actively involved in the regulation of the inflammatory and immune responses and have crucial importance in the outcome of spinal cord injuries (SCIs). Examining more objective and representative indicators of the patient's condition is still required to reveal the fundamental patterns of the abovementioned posttraumatic processes, including the identification of changes in the expression of cytokines. METHODS: We performed a dynamic (3, 7, and 14 days post-injury (dpi)) extended multiplex analysis of cytokine profiles in both CSF and blood serum of SCI patients with baseline American Spinal Injury Association Impairment Scale grades of A. RESULTS: The data obtained showed a large elevation of IL6 (>58 fold) in CSF and IFN-γ (>14 fold) in blood serum at 3 dpi with a downward trend as the post-traumatic period increases. The level of cytokine CCL26 was significantly elevated in both CSF and blood serum at 3 days post-SCI, while other cytokines did not show the same trend in the different biosamples. CONCLUSIONS: The dynamic changes in cytokine levels observed in our study can explore the relationships with the SCI region and injury severity, paving the way for a better understanding of the pathophysiology of SCI and potentially more targeted and personalized therapeutic interventions.

Video-based marker-free tracking and multi-scale analysis of mouse locomotor activity and behavioral aspects in an open field arena: A perspective approach to the quantification of complex gait disturbances associated with Alzheimer's disease.

Introduction: Complex gait disturbances represent one of the prominent manifestations of various neurophysiological conditions, including widespread neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Therefore, instrumental measurement techniques and automatic computerized analysis appears essential for the differential diagnostics, as well as for the assessment of treatment effectiveness from experimental animal models to clinical settings. Methods: Here we present a marker-free instrumental approach to the analysis of gait disturbances in animal models. Our approach is based on the analysis of video recordings obtained with a camera placed underneath an open field arena with transparent floor using the DeeperCut algorithm capable of online tracking of individual animal body parts, such as the snout, the paws and the tail. The extracted trajectories of animal body parts are next analyzed using an original computerized methodology that relies upon a generalized scalable model based on fractional Brownian motion with parameters identified by detrended partial cross-correlation analysis. Results: We have shown that in a mouse model representative movement patterns are characterized by two asymptotic regimes characterized by integrated 1/f noise at small scales and nearly random displacements at large scales separated by a single crossover. More detailed analysis of gait disturbances revealed that the detrended cross-correlations between the movements of the snout, paws and tail relative to the animal body midpoint exhibit statistically significant discrepancies in the Alzheimer's disease mouse model compared to the control group at scales around the location of the crossover. Discussion: We expect that the proposed approach, due to its universality, robustness and clear physical interpretation, is a promising direction for the design of applied analysis tools for the diagnostics of various gait disturbances and behavioral aspects in animal models. We further believe that the suggested mathematical models could be relevant as a complementary tool in clinical diagnostics of various neurophysiological conditions associated with movement disorders.

Combined Approaches Leading to Synergistic Therapeutic Effects in Spinal Cord Injury: State of the Art.

Cell-based regenerative medicine approaches and motor rehabilitation are currently being used to overcome the consequences of spinal cord injury (SCI). However, their success in preclinical studies does not always translate into successful implementation in clinical practice. Recent work suggests that modern neuromodulation approaches hold great therapeutic promise. Despite these advances, the complete resolution of functional deficits caused by SCI is impossible, especially in cases of severe injury. Therefore, combined approaches based on cell transplantation and neuromodulation are needed to enhance the neuroregenerative effect. The additional inclusion of a dosed locomotor load in the overall therapeutic plan and against a background of combined approaches can have a significant supportive effect. The aim of this review is to evaluate studies that use combinations of different approaches, thereby advancing our current understanding of the mechanisms that underlie their therapeutic effect. This review will consider mostly the effects and limitations of regenerative approaches, as well as the effects of locomotor load and neuromodulation on molecular and cellular changes in the spinal cord.

Molecular diagnostics in neurotrauma: Are there reliable biomarkers and effective methods for their detection?

To date, a large number of studies are being carried out in the field of neurotrauma, researchers not only establish the molecular mechanisms of the course of the disorders, but are also involved in the search for effective biomarkers for early prediction of the outcome and therapeutic intervention. Particular attention is paid to traumatic brain injury and spinal cord injury, due to the complex cascade of reactions in primary and secondary injury that affect pathophysiological processes and regenerative potential of the central nervous system. Despite a wide range of methods available methods to study biomarkers that correlate with the severity and degree of recovery in traumatic brain injury and spinal cord injury, development of reliable test systems for clinical use continues. In this review, we evaluate the results of recent studies looking for various molecules acting as biomarkers in the abovementioned neurotrauma. We also summarize the current knowledge of new methods for studying biological molecules, analyzing their sensitivity and limitations, as well as reproducibility of results. In this review, we also highlight the importance of developing reliable and reproducible protocols to identify diagnostic and prognostic biomolecules.

A Comparative Study of Mesenchymal Stem Cell-Derived Extracellular Vesicles' Local and Systemic Dose-Dependent Administration in Rat Spinal Cord Injury.

Spinal cord injury (SCI) is a serious neurological condition that causes severe disability. One of the approaches to overcoming the complications of SCI is stem cell-derived extracellular vesicle (EV) therapy. In this research, we performed a comparative evaluation of rat spinal cord post-traumatic regeneration efficacy using different methods of mesenchymal stem cell-derived EV transplantation (local vs. systemic) followed by evaluation of their minimal therapeutic dose. The results suggested that MSC-EV therapy could improve locomotor activity over 60 days after the SCI, showing a dose-dependent effect on the recovery of spinal cord motor pathways. We also established the possibility of maintaining a population of mature oligodendrocytes by MSC-EVs. It was observed that in the spinal cord injury area, intravenous transplantation of MSC-EVs showed more pronounced therapeutic effects compared to the treatment of fibrin matrix-encapsulated MSC-EVs.

Cellular and Molecular Gradients in the Ventral Horns With Increasing Distance From the Injury Site After Spinal Cord Contusion.

To identify cellular and molecular gradients following spinal cord injury (SCI), a rat contusion model of severe SCI was used to investigate the expression of NG2 and molecules that identify astrocytes and axons of the ventral horns (VH) at different distances on 7 and 30 days post-injury (dpi). A gradient of expression of NG2+/Olig2+ cells was determined, with the highest concentrations focused close to the injury site. A decrease in NG2 mean intensity correlates with a decrease in the number of NG2+ cells more distally. Immunoelectron microscopy subsequently revealed the presence of NG2 in connection with the membrane and within the cytoplasm of NG2+ glial cells and in large amounts within myelin membranes. Analysis of the astrocyte marker GFAP showed increased expression local to injury site from 7 dpi, this increase in expression spread more distally from the injury site by 30 dpi. Paradoxically, astrocyte perisynaptic processes marker GLT-1 was only increased in expression in areas remote from the epicenter, which was traced both at 7 and 30 dpi. Confocal microscopy showed a significant decrease in the number of 5-HT+ axons at a distance from the epicenter in the caudal direction, which is consistent with a decrease in ß3-tubulin in these areas. The results indicate significant cellular and molecular reactions not only in the area of the gray matter damage but also in adjacent and remote areas, which is important for assessing the possibility of long-distance axonal growth.