Synergistic neuroprotective effects of hyperbaric oxygen and N-acetylcysteine against traumatic spinal cord injury in rat

Combination use of human menstrual blood stem cell- derived exosomes and hyperbaric oxygen therapy, synergistically promote recovery after spinal cord injury in rats

Traumatic spinal cord injury (TSCI) is one of the catastrophic events in the nervous system that leads to the loss of sensory and motor function of the spinal cord at the site of injury. Considering that several factors such as apoptosis, inflammation, and oxidative stress play a role in the spread of damage caused by trauma, therefore, the treatment should also be based on multifactorial approaches. Currently, we investigated the effects of human menstrual blood stem cells (MenSCs)-derived exosomes in combination with hyperbaric oxygen therapy (HBOT) in the recovery of TSCI in rats. Ninety male mature Sprague-Dawley (SD) rats were planned into five equal groups, including; control group, TSCI group, Exo group (underwent TSCI and received MenSCs -derived exosomes), HBOT group (underwent TSCI and received HBOT), and Exo+HBOT group (underwent TSCI and received MenSCs -derived exosomes plus HBOT). After the behavioral evaluation, tissue samples were obtained for stereological, immunohistochemical, biochemical, and molecular assessments. Our results showed that the numerical density of neurons, the concentrations of antioxidative biomarkers (CAT, GSH, and SOD), and neurological function scores were significantly greater in the treatments group than in the TSCI group, and these changes were more obvious in the Exo+HBOT ones (P<0.05). This is while the numerical densities of apoptotic cells and glial cells, the levels of an oxidative factor (MDA) and proinflammatory cytokines (IL-1β and TNF-α) were considerably decreased in the treatment groups, specially the Exo+HBOT group, compared to the TSCI group (P<0.05). We conclude that the co-administration of exosomes derived from MenSCs and HBOT has more neuroprotective effects in animals with TSCI.

Recent advances in the application of gasotransmitters in spinal cord injury

Spinal Cord Injury (SCI) is a condition characterized by complete or incomplete motor and sensory impairment, as well as dysfunction of the autonomic nervous system, caused by factors such as trauma, tumors, or inflammation. Current treatment methods primarily include traditional approaches like spinal canal decompression and internal fixation surgery, steroid pulse therapy, as well as newer techniques such as stem cell transplantation and brain-spinal cord interfaces. However, the above methods have limited efficacy in promoting axonal and neuronal regeneration. The challenge in medical research today lies in promoting spinal cord neuron regeneration and regulating the disrupted microenvironment of the spinal cord. Studies have shown that gas molecular therapy is increasingly used in medical research, with gasotransmitters such as hydrogen sulfide, nitric oxide, carbon monoxide, oxygen, and hydrogen exhibiting neuroprotective effects in central nervous system diseases. The gas molecular protect against neuronal death and reshape the microenvironment of spinal cord injuries by regulating oxidative, inflammatory and apoptotic processes. At present, gas therapy mainly relies on inhalation for systemic administration, which cannot effectively enrich and release gas in the spinal cord injury area, making it difficult to achieve the expected effects. With the rapid development of nanotechnology, the use of nanocarriers to achieve targeted enrichment and precise control release of gas at Sites of injury has become one of the emerging research directions in SCI. It has shown promising therapeutic effects in preclinical studies and is expected to bring new hope and opportunities for the treatment of SCI. In this review, we will briefly outline the therapeutic effects and research progress of gasotransmitters and nanogas in the treatment of SCI.

Impact of Thermo-Responsive N-Acetylcysteine Hydrogel on Dermal Wound Healing and Oral Ulcer Regeneration

This study investigates the efficacy of a thermo-responsive N-acetylcysteine (NAC) hydrogel on wound healing and oral ulcer recovery. Formulated by combining NAC with methylcellulose, the hydrogel's properties were assessed for temperature-induced gelation and cell viability using human fibroblast cells. In vivo experiments on Sprague Dawley rats compared the hydrogel's effects against saline, NAC solution, and a commercial NAC product. Results show that a 5% NAC and 1% methylcellulose solution exhibited optimal outcomes. While modest improvements in wound healing were observed, significant enhancements were noted in oral ulcer recovery, with histological analyses indicating fully regenerated mucosal tissue. The study concludes that modifying viscosity enhances NAC retention, facilitating tissue regeneration. These findings support previous research on the beneficial effects of antioxidant application on damaged tissues, suggesting the potential of NAC hydrogels in improving wound care and oral ulcer treatment.

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.

Human Placental Mesenchymal Stem Cell-derived Exosomes in Combination with Hyperbaric Oxygen Synergistically Promote Recovery after Spinal Cord Injury in Rats

Spinal cord injury (SCI) is a critical medical condition during which sensorimotor function is lost. Current treatments are still unable to effectively improve these conditions, so it is important to pay attention to other effective approaches. Currently, we investigated the combined effects of human placenta mesenchymal stem cells (hPMSCs)-derived exosomes along with hyperbaric oxygen (HBO) in the recovery of SCI in rats. Ninety male mature Sprague-Dawley (SD) rats were allocated into five equal groups, including; sham group, SCI group, Exo group (underwent SCI and received hPMSCs-derived exosomes), HBO group (underwent SCI and received HBO), and Exo+HBO group (underwent SCI and received hPMSCs-derived exosomes plus HBO). Tissue samples at the lesion site were obtained for the evaluation of stereological, immunohistochemical, biochemical, molecular, and behavioral characteristics. Findings showed a significant increase in stereological parameters, biochemical factors (GSH, SOD, and CAT), IL-10 gene expression and behavioral functions (BBB and EMG Latency) in treatment groups, especially Exo+HBO group, compared to SCI group. In addition, MDA levels, the density of apoptotic cells and gliosis, as well as expression of inflammatory genes (TNF-α and IL-1β) were considerably reduced in treatment groups, especially Exo+HBO group, compared to SCI group. We conclude that co-administration of hPMSCs-derived exosomes and HBO has synergistic neuroprotective effects in animals undergoing SCI.

Combined Use of Serum N-terminal Pro-B-Type Natriuretic Peptide and Glypican-6 in the Diagnosis of Heart Failure

OBJECTIVE

The aim of this study was to investigate the efficacy of serum glypican-6 (GPC-6) levels and the combination of N-terminal pro-B-type natriuretic peptide (NT-ProBNP) and GPC-6 in the diagnosis of heart failure (HF).

METHODS

In this prospective study, patients older than 18 years of age, admitted to the emergency department of our hospital between December 2021 and April 2022, diagnosed with heart failure (patient group), and healthy volunteers with similar sociodemographic characteristics (control group) were included. The disease severity classification of the patient group was made according to the 2021 ESC guidelines, using echocardiographic findings. Serum GPC-6 and NT-ProBNP levels were measured by the enzyme-linked immunosorbent assay (ELISA) method, which determines the antigen-antibody relationship. Optimal GPC-6 and NT-ProBNP levels for the diagnosis of HF were determined by receiver operating characteristic (ROC) analysis. The patients were divided into three groups according to these levels. Group 1 consisted of patients with both markers below the cutoff values, Group 2 consisted of patients with either of these markers above the cutoff values, and Group 3 consisted of patients with both markers above the cutoff values.

RESULTS

The study included 65 heart failure patients and 20 healthy volunteers. When the patient and control groups were compared in terms of serum GPC-6 and serum NT-ProBNP levels, both parameters were evaluated as significantly higher in the patient group (p=0.038 and p<0.001; respectively). In the ROC analysis, it was determined that GPC-6 indicated HF with 58.46% sensitivity and 75% specificity for an optimal cutoff value of 390 pg/ml. In the ROC analysis, it was determined that serum NT-ProBNP indicated HF with 89.23% sensitivity and 70% specificity for an optimal cutoff value of 122 pg/ml. When the groups were compared according to the rate of HF, it was found to be higher in Group 3 compared to Group 2 (97.1% vs. 70.3%, p<0.002) and Group 1 (97.1% vs. 38.5%, p<0.001). This rate was seen to be significantly higher in Group 2 compared to Group 1 (70.3% vs. 38.5%, p=0.042).

CONCLUSION

The combination of GPC-6 and NT-ProBNP may help diagnose HF patients admitted to the emergency department.

Hyperbaric Oxygen in Combination with Epigallocatechin-3-Gallate Synergistically Enhance Recovery from Spinal Cord Injury in Rats

Spinal cord injury (SCI) following trauma is a devastating neurological event that can lead to loss of sensory and motor functions. However, the most effective measures to prevent the spread of damage are treatment measures in the early stages. Currently, we investigated the combined effects of hyperbaric oxygen (HBO) along with epigallocatechin-3-gallate (EGCG) in the recovery of SCI in rats. Ninety male mature Sprague-Dawley rats were randomly planned into five equal groups (n = 18). In addition to sham group that only underwent laminectomy, SCI rats were allocated into 4 groups as follows: control group; HBO group; EGCG group; and HBO + EGCG group. Tissue samples at the lesion site were obtained for stereological, immunohistochemical, biochemical, and molecular evaluation. In addition, behavioral tests were performed to assess of neurological functions. The finding indicated that the stereological parameters, antioxidant factors (CAT, GSH, and SOD), IL-10 gene expression levels and neurological functions were considerably increased in the treatment groups in comparison with control group, and these changes were more obvious in the HBO + EGCG group (P < 0.05). On the other hand, we observed that the density of apoptotic cells and gliosis, the biochemical levels of MDA and the expression levels of inflammatory genes (TNF-α and IL-1β) in the treatment groups, especially the HBO + EGCG group, were considerably reduced in comparison with control group (P < 0.05). We conclude that co-administration of HBO and EGCG has a synergistic neuroprotective effects in animals undergoing SCI.

Efficacy of combination of N-acetylcysteine and primrose in spinal cord injury; an experimental study

Introduction

Spinal cord trauma represents a major cause of emergency department admissions, with high morbidity and mortality rates. It requires early and urgent treatment. This experimental study assessed the effectiveness of a combination of primrose and N-acetylcysteine (NAC) in managing spinal cord injury (SCI).

Methods

We divided 46 adult male Wistar albino rats (6-8 months old, weighing 300-350 g) into five groups. Group 1 (n = 10) received only primrose; group 2 (n = 10) received only NAC; group 3 (n = 10) received a combination of NAC and primrose; group 4 (n = 10) received no intervention (first control group); group 5 (n = 10) underwent laminectomy only (second control group). Intergroup neurological and motor function were evaluated on days 1, 7, and 14. Oxidative biochemical markers, such as superoxide dismutase (SOD), glutathione peroxidase (GPX), and malondialdehyde (MDA), were measured.

Results

Significant differences were recorded in the GPX, SOD, and MDA values of groups 1, 2, 3, and 4 (p < 0.001, p = 0.005, and p = 0.097, respectively). Groupwise comparisons were conducted to identify the clinical significance of these markers. GPX and SOD levels were significantly higher in group 1 than in group 2; MDA levels were lower in group 1. GPX and SOD levels were significantly higher than in group 3 than in group 1; MDA levels were lower in group 3. Compared with group 5, group 1 demonstrated significantly higher GPX and SOD levels and lower MDA levels. Results in group 2 were similar to results in group 5. In group 3, GPX and SOD levels were significantly higher than in groups 2 and 5; MDA levels were significantly lower. Comparisons according to inclined plane angle level and motor function values revealed significant results on day 14, in favor of group 3 rats that had received the combined treatment.

Conclusion

The combined administration of NAC and primrose for traumatic SCI was more effective than either treatment alone in terms of improving biochemical and neurological functions. These findings suggest that the combination of NAC and primrose can serve as an effective treatment option for traumatic SCI.

Quercetin in combination with hyperbaric oxygen therapy synergistically attenuates damage progression in traumatic spinal cord injury in a rat model

BACKGROUND

Oxidative stress, inflammation and cell apoptosis are the most important destructive factors in the spread of damage following trauma to the spinal cord. Therefore, presently, we investigated the synergistic effects of quercetin along with hyperbaric oxygen therapy (HBOT) as strong antioxidant, anti-inflammatory and anti-apoptotic compounds in the recovery of traumatic spinal cord injury (TSCI) in a rat model.

MATERIAL AND METHODS

Seventy-five male mature Sprague-Dawley rats allocated into 5 groups, including: Sham group (SG), TSCI group, Quercetin group (underwent TSCI and received quercetin), HBOT group (underwent TSCI and received HBOT), and Quercetin+ HBOT group (underwent TSCI and received quercetin plus HBOT). Finally, the spinal cord samples at the traumatic site were harvested and various characteristics were evaluated, including the total volumes of the spinal cord and its central cavity as well as the numerical density of neuron and glial cells by stereological method, oxidant (malondialdehyde; MDA) and antioxidant (glutathione; GSH, superoxide dismutase; SOD and catalase; CAT) factors by biochemical method, molecular levels of IL-10, TNF-α and IL-1β by qRT-PCR method, and cell apoptosis by immunohistochemistry method against Caspase-3 antibody. Furthermore, Basso-Beattie-Bresnahan (BBB) and electromyography latency (EMG Latency) tests were performed to evaluate neurological functions.

RESULTS

Findings demonstrated that the stereological characteristics, biochemical factors (except MDA), expression of IL-10 gene and behavioral functions were significantly better in Quercetin, HBOT and Quercetin+HBOT groups than TSCI group, and were greater in Quercetin+HBOT ones (P < 0.05). While MDA levels, expression of TNF-α and IL-1β genes as well as the density of apoptotic cells significantly more decreased in Quercetin+HBOT group compared to other treated groups (P < 0.05).

CONCLUSION

Overall, co-administration of quercetin with HBOT has synergistic neuroprotective effects in animals underwent TSCI.

Oxidative stress disrupts the cytoskeleton of spinal motor neurons

BACKGROUND AND AIM

Traumatic spinal cord injury (SCI) is a common and devastating central nervous disease, the treatment of which faces many challenges to the medical community and society as a whole. Treatment measures based on oxidative stress of spinal motor neurons during SCI are expected to help restore biological functions of neurons under injury conditions. However, to date, there are no systematic reports regarding oxidative stress on spinal motor neuron injury. Our aim is to better understand and explain the influences and mechanisms of oxidative stress on spinal motor neurons during SCI.

METHODS

We first exposed VSC4.1 motor neurons to hydrogen peroxide (H₂ O₂ ) and evaluated the effects on cell viability, morphology, cycling, and apoptosis, with an emphasis on the changes to the cytoskeleton and the effect of N-acetyl-l-cysteine (NAC) on these changes. Then, we investigated the effects of NAC on these cytoskeletal changes in vitro and in vivo.

RESULTS

We found that H₂ O₂ caused severe damage to the normal cytoskeleton, leading to a reduction in neurite length and number, rearrangement of the actin cytoskeleton, and disorder of the microtubules and neurofilaments in VSC4.1. Importantly, NAC attenuated the oxidative damage of spinal motor neurons in vitro and in vivo, promoting the recovery of hindlimb motor ability in mice with SCI at the early stage of injury.

CONCLUSION

This study shows that oxidative stress plays an important role in the cytoskeleton destruction of spinal motor neurons in SCI, and treatment of SCI on this basis is a promising strategy. These findings will help to elucidate the role of oxidative stress in spinal motor neuron injury in SCI and provide references for further research into the study of the pathology and underlying mechanism of SCI.

Andrographolide contributes to spinal cord injury repair via inhibition of apoptosis, oxidative stress and inflammation

Background: Spinal cord injury (SCI) is a common disorder of the central nervous system with considerable socio-economic burden. Andrographolide (Andro), the main active component of Andrographis paniculata, has exhibited neuroprotective effects in different models of neurological diseases. The aim of this study was to evaluate the neuroprotective effects of Andro against SCI and explore the related mechanisms.

Methods: SCI was induced in rats by the Allen method, and the modeled animals were randomly divided into sham-operated, SCI, SCI + normal saline (NS) and SCI + Andro groups. The rats were injected intraperitoneally with Andro (1 mg/kg) or the same volume of NS starting day one after the establishment of the SCI model for 28 consecutive days. Post-SCI tissue repair and functional recovery were evaluated by measuring the spinal cord water content, footprint tests, Basso-Beattie-Bresnahan (BBB) scores, hematoxylin-eosin (HE) staining and Nissl staining. Apoptosis, oxidative stress and inflammation, as well as axonal regeneration and remyelination were analyzed using suitable markers. The in vitro model of SCI was established by treating cortical neurons with H₂O₂. The effects of Andro on apoptosis, oxidative stress and inflammation were evaluated as indicated.

Results: Andro treatment significantly improved tissue repair and functional recovery after SCI by reducing apoptosis, oxidative stress and inflammation through the nuclear factor E2-related factor 2/heme oxygenase-1 (Nrf-2/HO-1) and nuclear factor-kappa B (NF-κB) signaling pathways. Furthermore, Andro treatment promoted M2 polarization of the microglial cells and contributed to axonal regeneration and remyelination to improve functional recovery after SCI. In addition, Andro also attenuated apoptosis, oxidative stress and inflammation in H₂O₂-stimulated cortical neurons in vitro.

Conclusion: Andro treatment alleviated SCI by reducing apoptosis, oxidative stress and inflammation in the injured tissues and cortical neurons, and promoted axonal regeneration and remyelination for functional recovery.