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.

[Influence of inhalation injury on fluid resuscitation of massive burn patients during shock stage]

Objective: To explore the influence of inhalation injury on fluid resuscitation of massive burn patients during shock stage. Methods: A total of 74 massive burn patients (65 males and 9 females, aged 21 to 65 years) admitted to the Second Affiliated Hospital of Air Force Medical University (n=57) and Yan'an University Affiliated Hospital (n=17) from May 2009 to December 2019 were enrolled in this retrospective cohort study. Patients were divided into inhalation injury group (n=56) and non-inhalation injury group (n=18) based on clinical symptoms, vital signs, and results of bronchofibroscopy. Then 26 patients in inhalation injury group and 13 patients in non-inhalation injury group were 1∶2 matched by case-control matching based on the difference of total burn surface area. The total fluid replacement coefficient, crystalloid replacement coefficient, colloid replacement coefficient, glucose input volume, ratio of crystalloid to colloid, urine volume, and cumulative ratio of input to output volume during the first 24 h post injury, the second 24 h post injury, and the third 24 h post injury, heart rate, respiratory rate, mean arterial pressure (MAP), and hematocrit (HCT) at post injury hour (PIH) 24, 48, and 72 were recorded and compared between the two groups. Data were statistically analyzed with analysis of variance for repeated measurement and Bonferroni correction, t test, Fisher's exact probability test, and Mann-Whitney U test. Results: (1) After matching, during the first to third 24 h post injury, the total fluid replacement coefficient and glucose input volume of patients in inhalation injury group were significantly higher than those in non-inhalation injury group (F=4.202, 10.671, P<0.05 or P<0.01). During the first, second, and third 24 h post injury, the total fluid replacement coefficient, crystalloid replacement coefficient, colloid replacement coefficient, and ratio of crystalloid to colloid were similar between the patients in two groups(t=-1.336, -1.452, -1.998; -0.148, 0.141, 0.561; 0.916, -0.046, -0.509; -1.024, 0.208, 0.081, P>0.05). During the first, second, and third 24 h post injury, the glucose input volume of patients in inhalation injury group were respectively (2 996±1 176), (2 659±1 030), and (2 680±1 509) mL, which were significantly higher than (2 125±898), (1 790±828), and (1 632±932) mL in non-inhalation injury group (t=-2.334, -2.639, -2.297, P<0.05). (2) After matching, in overall comparison between groups, during the first to third 24 h post injury, the urinary output volumes and cumulative ratios of input to output volume of patients in inhalation injury group were significantly lower or higher than those in non-inhalation injury group, respectively (F=12.158, 9.111, P<0.01). At PIH 24, 48, and 72, heart rate of patients in inhalation injury group were significantly higher than those in non-inhalation injury group (F=4.675, P<0.05). There were no statistically significant differences in heart rate, respiratory rate, MAP, and HCT between patients in the two groups at PIH 24 and 48 (t=-0.039, -1.688, 1.399, 1.299, -1.741, 0.754, -0.677, 0.037, P>0.05). During the first and second 24 h post injury, the urine volume and cumulative ratio of input to output volume of patients in inhalation injury group were respectively significantly lower and higher than those in non-inhalation injury group (t(urine volume)=2.421, 2.876, t(cumulative ratio of input to output volume)=-2.687、-2.943, P<0.05 or P<0.01). At PIH 72, the heart rate and HCT of patients in inhalation injury group ( (114±13) times/min, 0.42±0.06) were significantly higher than those in non-inhalation injury group ( (98±18) times/min, 0.38±0.06, t=-3.182, -2.123, P<0.05 or P<0.01), there were no statistically significant differences in respiratory rate and MAP between the patients in two groups (t=0.359, 1.722, P>0.05). During the third 24 h post injury, there were no statistically significant differences in urine volume and cumulative ratio of input to output volume between the patients in two groups (t=1.664, -1.895, P>0.05). Conclusions: The presence of inhalation injury can lead to increased fluid requirement in massive burn patients during shock stage. An appropriate increase of fluid volume in the fluid resuscitation of burn patients combined with inhalation injury would be beneficial for maintaining ideal urine output.

[Analysis of 118 cases of benign paroxysmal positional vertigo after trauma]

Objective:The aim of this study is to retrospective analysis the clinic features of 118 cases of benign paroxysmal positional vertigo after trauma. Method:Analyzes clinic features of injury in 118 cases of benign paroxysmal positional vertigo after trauma, and classified and localized the craniocerebral trauma. The 118 cases were tested with different positioning tests in the sequence of Dix hallpike test and rolling test. Then, proper otolith manual reduction was given. Result:In 118 cases of BPPV after trauma including 35 cases of skull fracture, 6 cases of concussion, 17 cases of scalp hematoma, 28 cases of scalp laceration, 14 cases of mild brain contusion and 18 cases of head combined injury. The distributions of head injury were 57 at front temporal, 24 at top, 22 at occipital and 15 at maxillofacial region. The latency of BPPV after head injury varies from 1day to 1month. The incidence of 3-7 day after head injury was the highest, followed by 7-14 days, 0-3 days, and the lowest incidence rate of 14 day to 1 month. Canal type 118 BPPV patients after head injury accounting for up to 57.6% of the horizontal semicircular canal accounted for 33.1%, mixed 9.3%. Conclusion:The patients with front temporal trauma and skull fracture were prone to have BPPV. The peak incidence of BPPV was 3-14 days after head injury. The most common type of BPPV was PC BPPV, and the HC BPPV was the second type. A good curative effect can be manipulative reduction after trauma BPPV..

Identification and analysis of the TIFY gene family in Gossypium raimondii

The highly conserved TIFY domain is included in the TIFY protein family of transcription factors, which is important in plant development. Here, 28 TIFY family genes were identified in the Gossypium raimondii genome and classified into JAZ (15 genes), ZML (8), PPD (3), and TIFY (2). The normal (TIF[F/Y]XG) motif was dominant in the TIFY family, excluding the ZML subfamily, in which TLSFXG was prevalent. TIFY family genes were unevenly distributed in the G. raimondii genome, with TIFY clusters present on chromosome 9. Phylogenetic analysis indicated abundant variations in the G. raimondii TIFY family, which were most closely related to those in Theobroma cacao among 5 species. Exon-intron organization and intron phases were homologous within each subfamily, correlating with their phylogeny. Intra-species synteny analyses indicated that genomic duplication contributed to the expansion of the TIFY family. Inter-species synteny analyses indicated that synteny regions involved in G. raimondii TIFY family genes were also present in the comparison of G. raimondii vs Arabidopsis thaliana or T. cacao, signifying that these genes had common ancestors and play the same or similar roles in biological processes. Greater synteny was present in the comparison of G. raimondii vs T. cacao than of G. raimondii vs A. thaliana. The expression patterns of TIFY family genes were characterized and most TIFY family genes were indicated to be involved in fiber development. Our study provides new data related to the evolution of TIFYs and their role as important regulators of transcription; these data can be useful for fiber development.

Investigation of polymorphisms in exon7 of the NSUN7 gene among Chinese Han men with asthenospermia

Previous studies have shown that genetic polymorphisms in exon7 of the NSUN7 gene can be used as an infertility marker in Iranian men with asthenospermia. However, there have been no equivalent studies in China. In the present study, we investigated the possible association between the genetic polymorphisms in exon7 of NSUN7 and asthenospermia in a Chinese Han population. We recruited 240 asthenospermic men as a patient group and 256 normospermic men as a control group, and analyzed the semen parameters on the basis of World Health Organization (WHO) guidelines. The genetic polymorphisms in exon7 of NSUN7 were detected by DNA sequence analysis. The results were analyzed statistically and a P value < 0.05 was considered significant. There were two genetic polymorphisms, c.906C>T and c.922T>G, in exon7 of NSUN7. We found relatively similar genotypes and allele frequencies between the two groups (P = 0.928, P = 0.928, respectively). The combined genotypes of the two polymorphisms did not identify a haplotype associated with asthenospermia (P = 0.824, P = 0.824, respectively). Our findings revealed that genetic polymorphisms in exon7 of the NSUN7 gene are not associated with asthenospermia in Chinese Han men.

SLC30A8 polymorphism and type 2 diabetes risk: evidence from 27 study groups

BACKGROUND AND AIMS

Intense research has been performed to identify the genetic risk factors in type 2 diabetes, and a single nucleotide polymorphism (SNP) in SLC30A8 (rs13266634) was reported to be associated with type 2 diabetes mellitus. However, published data on the association between SLC30A8 polymorphism and the risk of type 2 diabetes were inconsistent. Therefore, we conducted this meta-analysis to derive a more precise estimation of the relationship.

METHODS AND RESULTS

We searched PubMed through October 2009 to identify all relevant papers. Odds ratios (ORs) and 95% confidence intervals (CIs) were extracted under an additive genetic model. In the current meta-analysis, we identified a total of 27 groups including 42,609 cases and 69,564 controls. In analyses of the case-control studies by ethnicity, the results indicated that SLC30A8 polymorphism was related to elevate risks of type 2 diabetes both in Europeans (OR=1.15, 95% CI 1.11-1.18, P<0.001) and Asians (OR=1.15, 95% CI 1.11-1.19, P<0.001). Next, we separated hospital-based case-control studies from population-based case-control studies, however, there was no apparent difference between population-based case-control study groups (OR=1.15, 95% CI 1.12-1.17, P<0.001) and hospital-based case-control study groups (OR=1.16, 95% CI 1.07-1.25, P<0.001).

CONCLUSION

Our present meta-analysis provided evidence that SLC30A8 (rs13266634) C allele carriers could elevate the risk of type 2 diabetes, especially in Europeans and Asians.