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.

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.

Conjugation of Triterpenic Acids of Ursane and Oleanane Types with Mitochondria-Targeting Cation F16 Synergistically Enhanced Their Cytotoxicity against Tumor Cells.

The present work shows the cytotoxic effects of novel conjugates of ursolic, oleanolic, maslinic, and corosolic acids with the penetrating cation F16 on cancer cells (lung adenocarcinoma A549 and H1299, breast cancer cell lines MCF-7 and BT474) and non-tumor human fibroblasts. It has been established that the conjugates have a significantly enhanced toxicity against tumor-derived cells compared to native acids and also demonstrate selectivity to some cancer cells. The toxic effect of the conjugates is shown to be due to ROS hyperproduction in cells, induced by the effect on mitochondria. The conjugates caused dysfunction of isolated rat liver mitochondria and, in particular, a decrease in the efficiency of oxidative phosphorylation, a decrease in the membrane potential, and also an overproduction of ROS by organelles. The paper discusses how the membranotropic- and mitochondria-targeted effects of the conjugates may be related to their toxic effects.

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.

Comparative Study of Cytotoxic and Membranotropic Properties of Betulinic Acid-F16 Conjugate on Breast Adenocarcinoma Cells (MCF-7) and Primary Human Fibroblasts.

The present study evaluates the cytotoxicity of a previously synthesized conjugate of betulinic acid (BA) with the penetrating cation F16 on breast adenocarcinoma (MCF-7) and human fibroblast (HF) cell lines, and also shows the mechanism underlying its membranotropic action. It was confirmed that the conjugate exhibits higher cytotoxicity compared to native BA at low doses also blocking the proliferation of both cell lines and causing cell cycle arrest in the G0/G1 phase. We show that the conjugate indeed has a high potential for accumulation in mitochondria, being visualized in these organelles, which is most pronounced in cancer cells. The effect of the conjugate was observed to be accompanied by ROS hyperproduction in both cancerous and healthy cells, despite the lower base level of ROS in the latter. Along with this, using artificial liposomes, we determined that the conjugate is able to influence the phase state of lipid membranes, make them more fluid, and induce nonspecific permeabilization contributing to the overall cytotoxicity of the tested agent. We conclude that the studied BA-F16 conjugate does not have significant selective cytotoxicity, at least against the studied breast cancer cell line MCF-7.

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.

Effect of F16-Betulin Conjugate on Mitochondrial Membranes and Its Role in Cell Death Initiation.

This work demonstrates the effects of a newly synthesized conjugate of the plant triterpenoid betulin and the penetrating cation F16 used for mitochondrial targeting. The resulting F16-betulin conjugate revealed a mitochondria-targeted effect, decreasing the mitochondrial potential and inducing superoxide overproduction in rat thymocytes in vitro. It has been suggested that this may cause the cytotoxic effect of the conjugate, which significantly exceeds the effectiveness of its precursors, betulin and F16. Using isolated rat liver mitochondria, we found that the F16-betulin conjugate has a surface-active effect on mitochondrial membranes, causing organelle aggregation. This effect of the derivative resulted in a dose-dependent decrease in mitochondrial transmembrane potential, as well as suppression of respiration and oxidative phosphorylation, especially in the case of nicotinamide adenine dinucleotide (NAD)-fueled organelles. In addition, the F16-betulin conjugate caused an increase in H2O2 generation by mitochondria fueled with glutamate and malate. These effects of the derivative can presumably be due to the powerful suppression of the redox activity of complex I of the mitochondrial electron transport chain. The paper discusses how the mitochondria-targeted effects of the F16-betulin conjugate may be related to its cytotoxic effects.

Mitochondria-targeted prooxidant effects of betulinic acid conjugated with delocalized lipophilic cation F16.

The paper examines the molecular mechanisms of the cytotoxicity of conjugates of betulinic acid with the penetrating cation F16. The in vitro experiments on rat thymocytes revealed that all the obtained F16-betulinic acid derivatives showed more than 10-fold higher cytotoxicity as compared to betulinic acid and F16. In this case, 0.5-1 µM of all conjugates showed mitochondria-targeted action, inducing superoxide overproduction and reducing the mitochondrial potential of cells. Experiments on isolated rat liver mitochondria revealed the ability of conjugates to dose-dependently reduce the membrane potential of organelles, as well as the intensity of respiration and oxidative phosphorylation, which is also accompanied by an increase in the production of hydrogen peroxide by mitochondria. It was shown that these actions of derivatives may be due to several effects: the reversion of ATP synthase, changes in the activity of complexes of the respiratory chain and permeabilization of the inner mitochondrial membrane. All compounds also demonstrated the ability to induce aggregation of isolated rat liver mitochondria. Using the model of lecithin liposomes, we found that the F6 conjugate (2 µM) induces the permeability of vesicle membranes for the fluorescent probe sulforhodamine B. High concentrations (25 µM) of the F6 derivative have been found to induce dynamic processes in the liposome membrane leading to aggregation and/or fusion of vesicle membranes. The paper discusses the relationship between the mitochondria-targeted effects of F16-betulinic acid conjugates and their cytotoxicity.