The Effect of Glycine and N-Acetylcysteine on Oxidative Stress in the Spinal Cord and Skeletal Muscle After Spinal Cord Injury.

Oxidative stress is a frequently occurring pathophysiological feature of spinal cord injury (SCI) and can result in secondary injury to the spinal cord and skeletal muscle atrophy. Studies have reported that glycine and N-acetylcysteine (GlyNAC) have anti-aging and anti-oxidative stress properties; however, to date, no study has assessed the effect of GlyNAC in the treatment of SCI. In the present work, we established a rat model of SCI and then administered GlyNAC to the animals by gavage at a dose of 200 mg/kg for four consecutive weeks. The BBB scores of the rats were significantly elevated from the first to the eighth week after GlyNAC intervention, suggesting that GlyNAC promoted the recovery of motor function; it also promoted the significant recovery of body weight of the rats. Meanwhile, the 4-week heat pain results also suggested that GlyNAC intervention could promote the recovery of sensory function in rats to some extent. Additionally, after 4 weeks, the levels of glutathione and superoxide dismutase in spinal cord tissues were significantly elevated, whereas that of malondialdehyde was significantly decreased in GlyNAC-treated animals. The gastrocnemius wet weight ratio and total antioxidant capacity were also significantly increased. After 8 weeks, the malondialdehyde level had decreased significantly in spinal cord tissue, while reactive oxygen species accumulation in skeletal muscle had decreased. These findings suggested that GlyNAC can protect spinal cord tissue, delay skeletal muscle atrophy, and promote functional recovery in rats after SCI.

Glycine and N-Acetylcysteine (GlyNAC) Combined with Body Weight Support Treadmill Training Improved Spinal Cord and Skeletal Muscle Structure and Function in Rats with Spinal Cord Injury.

Skeletal muscle atrophy is a frequent complication after spinal cord injury (SCI) and can influence the recovery of motor function and metabolism in affected patients. Delaying skeletal muscle atrophy can promote functional recovery in SCI rats. In the present study, we investigated whether a combination of body weight support treadmill training (BWSTT) and glycine and N-acetylcysteine (GlyNAC) could exert neuroprotective effects, promote motor function recovery, and delay skeletal muscle atrophy in rats with SCI, and we assessed the therapeutic effects of the double intervention from both a structural and functional viewpoint. We found that, after SCI, rats given GlyNAC alone showed an improvement in Basso-Beattie-Bresnahan (BBB) scores, gait symmetry, and results in the open field test, indicative of improved motor function, while GlyNAC combined with BWSTT was more effective than either treatment alone at ameliorating voluntary motor function in injured rats. Meanwhile, the results of the skeletal muscle myofiber cross-sectional area (CSA), hindlimb grip strength, and acetylcholinesterase (AChE) immunostaining analysis demonstrated that GlyNAC improved the structure and function of the skeletal muscle in rats with SCI and delayed the atrophication of skeletal muscle.

Mechanism of skeletal muscle atrophy after spinal cord injury: A narrative review.

Spinal cord injury leads to loss of innervation of skeletal muscle, decreased motor function, and significantly reduced load on skeletal muscle, resulting in atrophy. Factors such as braking, hormone level fluctuation, inflammation, and oxidative stress damage accelerate skeletal muscle atrophy. The atrophy process can result in skeletal muscle cell apoptosis, protein degradation, fat deposition, and other pathophysiological changes. Skeletal muscle atrophy not only hinders the recovery of motor function but is also closely related to many systemic dysfunctions, affecting the prognosis of patients with spinal cord injury. Extensive research on the mechanism of skeletal muscle atrophy and intervention at the molecular level has shown that inflammation and oxidative stress injury are the main mechanisms of skeletal muscle atrophy after spinal cord injury and that multiple pathways are involved. These may become targets of future clinical intervention. However, most of the experimental studies are still at the basic research stage and still have some limitations in clinical application, and most of the clinical treatments are focused on rehabilitation training, so how to develop more efficient interventions in clinical treatment still needs to be further explored. Therefore, this review focuses mainly on the mechanisms of skeletal muscle atrophy after spinal cord injury and summarizes the cytokines and signaling pathways associated with skeletal muscle atrophy in recent studies, hoping to provide new therapeutic ideas for future clinical work.

Inhibition by rno-circRNA-013017 of the apoptosis of motor neurons in anterior horn and descending axonal degeneration in rats after traumatic spinal cord injury.

Introduction: Spinal cord injury (SCI) often causes continuous neurological damage to clinical patients. Circular RNAs (circRNAs) are related to a lot of diseases, including SCI. We previously found five candidate circRNAs which were likely to regulate the secondary pathophysiological changes in rat model after traumatic SCI. Methods: In this study, we first selected and overexpressed target circRNA in rats. We then explored its functional roles using various functional assays in a rat model after SCI. Results: We found that rno-circRNA-013017-the selected target circRNA-reduced neuron apoptosis, preserved the survival and activity of motor neurons, and regulated apoptosis-related proteins at 3 days post-SCI using western blot, immunofluorescence and polymerase chain reaction. Additionally, we found that rno-circRNA-013017 inhibited descending axonal degeneration and preserved motor neurons and descending axons at 6 weeks post-SCI using immunofluorescence, biotin dextran amine diffusion tensor imaging. Finally, the overexpression of rno-circRNA-013017 promoted the locomotor function of rats after SCI using open-field test and gait analysis. Conclusion: Focusing on the functions of rno-circRNA-013017, this study provides new options for future studies exploring therapeutic targets and molecular mechanisms for SCI.

Thiourea leaching gold and silver from the printed circuit boards of waste mobile phones.

The present communication deals with the leaching of gold and silver from the printed circuit boards (PCBs) of waste mobile phones using an effective and less hazardous system, i.e., a thiourea leaching process as an alternative to the conventional and toxic cyanide leaching of gold. The influence of particle size, thiourea and Fe(3+) concentrations and temperature on the leaching of gold and silver from waste mobile phones was investigated. Gold extraction was found to be enhanced in a PCBs particle size of 100 mesh with the solutions containing 24 g/L thiourea and Fe(3+) concentration of 0.6% under the room temperature. In this case, about 90% of gold and 50% of silver were leached by the reaction of 2h. The obtained data will be useful for the development of processes for the recycling of gold and silver from the PCBs of waste mobile phones.

Prognostic value of the model for end-stage liver disease combined with serum sodium levels in patients with decompensated cirrhosis / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the ability of the model for end-stage liver disease (MELD) score combined with serum sodium measurements to effectively evaluate the prognosis of patients with decompensated liver cirrhosis.</p><p><b>METHODS</b>A total of 212 patients with decompensated cirrhosis were retrospectively analyzed. Each patient's MELD scores, and sodium-based MELD scores (MELD-Na, MELDNa, and MESO) were calculated at three-month intervals. The area under the receiver operating characteristic (ROC) curve (AUC) was used to compare the predictive abilities of the four scores for 3-, 6- and 12-month mortality. Kaplan-Meier survival curves were created using the best cut-off values for each score identified by the ROC.</p><p><b>RESULTS</b>Among the 212 patients, 46 died within three months, 56 died within six months, and 87 died within 12 months. The MELD, MELD-Na, MELDNa and MESO scores were significantly different between patients who survived and those who died within three and 12 months (P less than 0.01). The AUCs for the four separate scores were all more than 0.8 at the 3- and 6-month time points; however, the AUCs of MELDNa (3-month: 0.846; 6-month: 0.869) and MESO (0.831; 0.850) were significantly better than those of MELD (0.812; 0.841) (P less than 0.05). At the 12-month time point, the AUCs of MELD, MELD-Na, MELDNa, and MESO were not significantly different (0.774, 0.775, 0.786, and 0.777, respectively). Survival curves showed that all the scores were able to clearly discriminate the patients who survived from those who died within 12 months (P=0.000).</p><p><b>CONCLUSION</b>The MELD score and its sodium-based variants (MELD-Na, MELDNa, and MESO) can precisely predict mortality of patients with decompensated cirrhosis for short and intermediate periods. The MELDNa and MESO scores are superior for predicting 3- and 6-month survival.</p>