Neuroprotective effect of alpha-lipoic acid and methylprednisolone on the spinal cord ischemia/reperfusion injury in rabbits

Efficacy of Percutaneous Laser Disc Decompression (PLDD) Combined with an Oral Food Supplement for Lumbar Disc Herniation

Background: In recent years, minimally invasive treatment options for lumbar disc herniation, such as percutaneous laser disc decompression (PLDD), have been introduced to avoid more invasive surgical methods. Combining these minimally invasive approaches with nutraceuticals that are effective in neuroprotection and pain management may lead to better long-term outcomes. Methods: The present study evaluated the beneficial effects of a new oral food supplement composed of acetyl-L-carnitine, α-lipoic acid, quercetin, bromelain, pantothenic acid, and vitamins C, B1, B2, B6, and B12 in patients with neuropathic pain due to herniated lumbar discs treated with PLDD. Patients were divided into two groups of 26 patients each: group A underwent PLDD alone, while group B underwent PLDD followed by a dietary supplement for two months after surgery. Preoperative VAS scores for leg pain were recorded for both groups and no significant difference was observed (8.7 for Group A and 8.6 for Group B). Results: In Group A, the mean postoperative VAS score for leg pain at a 1-month follow-up was 2.5, which remained stable at 3 months. In Group B, the mean postoperative VAS score was 2.0 at 1-month and improved to 1.6 at the 3-month follow-up. According to self-reported leg pain assessments, 66.5% of the patients using the dietary supplement reported a significantly better pain condition, and 43.5% reported a somewhat better situation. In contrast, 7.7% of the patients who underwent PLDD alone reported no changes in leg pain at the final follow-up. Conclusions: The results of our study indicate that the oral food supplement could provide a safe and effective treatment in patients with painful radiculopathy, enhancing the recovery of sensory fiber function in lumbar nerve roots after surgical lumbar disc decompression.

Better neuroprotective profile of caffeic acid phenyl ester over resveratrol in non-traumatic ischemia-reperfusion injury of the spinal cord

BACKGROUND

Spinal cord ischemia has serious sequelae. The aim of this study is to investigate the effects of resveratrol and caffeic acid phenyl ester (CAPE), a propolis derivative, on spinal cord injury induced by ischemia-reperfusion (IR).

METHODS

In our research, 30 male Wistar albino rats, 200-250 gr, were used. Before the experiment, during a week of the process, the rats were fed with these two agents, and the experimental group rats were exposed to spinal cord IR injury. At the end of the experiment, spinal cord samples were taken from the sacrificed rats. Bax, p53, nNOS, and Beclin-1 immunoreactivity moreover TUNEL (+) cells were evaluated with immunohistochemically in the IR-induced damaged rats.

RESULTS

It has been clearly determined that the TUNEL (+) apoptotic cell number and immunopositive cells of nNOS, Beclin-1, p53, Bax were raised in the IR group. However, these increments partially were restored in the resveratrol and CAPE-fed rats with IR-induced injury.

CONCLUSION

In light of our data, resveratrol, and CAPE could be beneficial in spinal cord IR injury. Although both agents provide beneficial effects, it can be said that CAPE is partially more effective in spinal cord injury caused by IR.

Effects of Lipoic Acid on Ischemia-Reperfusion Injury

Ischemia-reperfusion (I/R) injury often occurred in some pathologies and surgeries. I/R injury not only harmed to physiological functions of corresponding organ and tissue but also induced multiple tissue or organ dysfunctions (even these in distant locations). Although the reperfusion of blood attenuated I/R injury to a certain degree, the risk of secondary damages was difficult to be controlled and it even caused failures of these tissues and organs. Lipoic acid (LA), as an endogenous active substance and a functional agent in food, owns better safety and effects in our body (e.g., enhancing antioxidant activity, improving cognition and dementia, controlling weight, and preventing multiple sclerosis, diabetes complication, and cancer). The literature searching was conducted in PubMed, Embase, Cochrane Library, Web of Science, and SCOPUS from inception to 20 May 2021. It had showed that endogenous LA was exhausted in the process of I/R, which further aggravated I/R injury. Thus, supplements with LA timely (especially pretreatments) may be the prospective way to prevent I/R injury. Recently, studies had demonstrated that LA supplements significantly attenuated I/R injuries of many organs, though clinic investigations were short at present. Hence, it was urgent to summarize these progresses about the effects of LA on different I/R organs as well as the potential mechanisms, which would enlighten further investigations and prepare for clinic applications in the future.

The Efficacy of Combined Medication With Methylprednisolone and Erythropoietin in the Treatment of Ischemia-Reperfusion Injury to the Spinal Cord in Patients With Cervical Spondylotic Myelopathy

Introduction

Cervical myelopathy (CM) is caused by degenerative or congenital changes in the discs and soft tissues of the cervical spine, leading to chronic compression of the spinal cord. The current treatment for moderate-to-severe CM is surgical decompression, which is effective in most cases; however, it can cause inflammation of the nervous system and spinal cord reperfusion injury, resulting in perioperative neurological complications and suboptimal neurological recovery. The aim of this study was to investigate the therapeutic effects of the combination of erythropoietin and methylprednisolone in the treatment of ischemia-reperfusion injury to the spinal cord and to analyze its effects on the levels of interleukin-1 beta (IL-1β), interleukin-1 receptor antagonist (IL-1RA), and interleukin-8 (IL-8).

Materials and methods

This study included 110 patients admitted to the hospital due to cervical spondylotic myelopathy. They were randomized into two groups of 55 patients each: a control and an observation group. In both groups of patients, fusion internal fixation and anterior cervical discectomy were performed. The difference, however, was that the control group received a rapid intravenous injection of 30 mg/kg methylprednisolone 30 minutes prior to spinal cord decompression, while the observation group received an intravenous injection of 30 mg/kg methylprednisolone and 3,000 U/kg erythropoietin 30 minutes before spinal cord decompression. The study was approved by the Hospital Ethical Committee of the Dow University of Health Sciences, Karachi. The neurological function of both groups of patients was assessed before the procedure and three months after the treatment using the Japanese Orthopedic Association (JOA) method of assessing spinal cord function (40-point rating method). Enzyme-linked immunosorbent assay (ELISA) was performed to measure the levels of neuron-specific enolase (NSE), S-100β, IL-1RA, IL-1β, and IL-8 in both groups. The quality of life of patients in both groups was assessed three months after the treatment with the World Health Organization Quality of Life assessment instrument (WHOQOL-100).

Results

Before the treatment, there was no significant variance between the two groups in the JOA score and the 40-point rating method. Similarly, there was no significant difference in the levels of IL-1β, IL-1RA, and IL-8 between the two groups (p-value = 0.262, 0.387, and 0.154 respectively) prior to the treatment. Three months after the treatment, the levels of IL-1β and IL-8 in the observation group were 21.83 ±3.65 ng/l and 357.07 ±32.36 ng/l respectively, both lower than the control group value (p-value = 0.026, 0.028 respectively). The level of IL-1RA in follow-up was 21.59 ±1.15 ng/l, which was higher than that in the control group. Three months after the treatment, all the WHOQOL-100 parameters of the observation group for psychology, physiology, social relations, independence, spirituality, environment, and general quality of life were higher than those of the control group; the variance among the groups was statistically significant (p-value: <0.001).

Conclusions

The combination therapy with erythropoietin and methylprednisolone is effective for ischemia-reperfusion injuries of the spinal cord. It also reduces S-100β and NSE, inhibits IL-1β, and increases IL-8 and IL-1RA. Therefore, it preserves and improves spinal nerve function and the quality of life of patients.

Angiopoietin-1 Protects Spinal Cord Ischemia and Reperfusion Injury by Inhibiting Autophagy in Rats

Spinal cord ischemia and reperfusion (SCIR) injury can induce autophagy, which is involved in the survival of neurons. However, whether autophagy plays a neuroprotective or a detrimental role in SCIR injury remains controversial. Angiopoietin-1 (Ang-1), an endothelial growth factor, has been shown to have neuroprotective effects. The present study aimed to explore the neuroprotective mechanisms of Ang-1 in neuronal cells in a rat model of SCIR injury in vivo. Ang-1 protein and rapamycin were injected intrathecally. Basso Beattie Bresnahan (BBB) scoring and hematoxylin and eosin staining were used to assess the degree of SCIR injury. Proteins that reflected the level of autophagy expression, such as Beclin-1 and LC3, were evaluated by western blotting. The results indicated that SCIR injury resulted in loss in lower limb motor function. Ang-1 protein inhibited the expression of Beclin-1 and LC3, which improved the BBB score and alleviated spinal cord injury. In contrast, rapamycin, an autophagy activator, caused the opposite effect. This study provides evidence that Ang-1 plays a neuroprotective role by inhibiting of autophagy expression in SCIR injury. Overall, findings could be useful for the treatment of SCIR injury.

Time-dependent effects of dantrolene on motor evoked potentials in experimental spinal cord injuries

Objectives:Traumatic spinal cord injury (SCI) is a significant clinical problem with numerous secondary complications and perpetual deficits. No potent treatment is currently available to fully repair motor and other neurological functions. We studied the effects of dantrolene (DNT) at different time points, on the motor-evoked potentials (MEPs) and the apoptosis response in spinal cord injury. Methods:The study was conducted on a total of 38 rabbits divided into five main groups.These were group 1 (sham): only laminectomy (n = 6), group 2 (SCI): laminectomy and traumatic SCI (n = 8), group 3 (DNT 0h): just after the SCI, DNT 10 mg/kg I.P. (n = 8), group 4 (DNT 1h): 1 h after the SCI, DNT 10 mg/kg I.P. (n = 8), and group 5 (DNT 4h): 4 h after the SCI, DNT 10 mg/kg I.P. (n = 8). Results: DNT, which was administered as the treatment, had a therapeutic effect on the motor function. This effect was observed by recording neural transmission obtained via the Tarlov test and a transcranial magnetic stimulator by using the values of the MEPs. A significant decrease was histopathologically observed in the apoptotic cell count. Discussion: The electrophysiological efficacy of our model of trauma as SCI has been complemented with the significant differences between the control group and the SCI group. This creates a need for electrophysiological studies to be conducted in the future because effects, even at a minimum level, may play an important role in finding an applicable medicine for SCI.

Intermittent injection of Methylprednisolone Sodium Succinate in the treatment of Cervical Spinal Cord injury complicated with incomplete paraplegia

OBJECTIVE

To evaluate the clinical efficacy and safety of intermittent injection of methylprednisolone sodium succinate in the treatment of cervical spinal cord injury complicated with incomplete paraplegia.

METHODS

Seventy-eight patients with cervical spinal cord injury complicated with incomplete paraplegia who were admitted between August 2016 and December 2017 were enrolled and grouped into an observation group and a control group using random number table, 39 in each group. Patients in the control group were given vertebral body decompression and bone grafting and internal fixation according to the severity of spinal cord compression, while patients in the observation group were treated by methylprednisolone sodium succinate in addition to the same treatment as the control group. The clinical efficacy and medicine associated adverse reactions were compared between the two groups.

RESULTS

The cure rate of the observation group was significantly higher than that of the control group (46.2% (18/39) vs. 20.5% (8/39)). After the treatment, the Japanese Orthopaedic Association (JOA) score and American Spinal Cord Injury Association (ASIA) score of the two groups after treatment were significantly higher compared to before treatment, and the scores of the observation group were much higher than those of the control group (P<0.05). The incidence of adverse reactions of the observation and control groups was 15.4% and 17.9% respectively, and the difference was not statistically significant (P>0.05).

CONCLUSION

Intermittent injection of methylprednisolone sodium succinate has definite efficacy in treating cervical spinal cord injury complicated with incomplete paraplegia, with a low incidence of adverse reactions; hence it is worth promotion.

Effect of Alpha-Lipoic Acid on Clinical and Neurophysiologic Recovery of Carpal Tunnel Syndrome: A Double-Blind, Randomized Clinical Trial

The objective of our study was to examine the effect of alpha-lipoic acid (ALA) on clinical and neurophysiologic outcomes after surgery for idiopathic carpal tunnel syndrome (CTS). We conducted a randomized, double-blind, placebo-controlled clinical trial in 20 adults diagnosed with idiopathic CTS after clinical and neurophysiologic assessment. Eligible participants took 600 mg ALA or placebo per day for 1 month before surgery, and for 2 months afterward. Further clinical and neurophysiologic assessments were undertaken immediately before surgical decompression, and at 12 weeks postoperatively with additional clinical assessments at the 4th and 8th week after surgery. Clinical outcome measures were taken by Boston Questionnaire score, the presence or absence of Tinel's sign, and Phalen's test findings. Median nerve conduction studies were also undertaken and interpreted according to Dumitru's reference values. Nineteen patients completed the study; one member of the placebo group was lost during follow-up. There were significant improvements in clinical and neurophysiologic variables in the ALA treatment group, present even before surgery. Boston Questionnaire scores had improved significantly in both groups. In the ALA group, none of the participants had positive Phalen's or Tinel's signs at 12 weeks, and motor and sensory fiber latency and amplitude had significantly improved; in the placebo group, only the sensory distal latency had improved significantly. In conclusion, ALA administered 1 month before open decompression and for 2 months afterward improves the clinical and neurophysiologic outcomes after surgery.

Methotrexate combined with methylprednisolone for the recovery of motor function and differential gene expression in rats with spinal cord injury

Methylprednisolone is a commonly used drug for the treatment of spinal cord injury, but high doses of methylprednisolone can increase the incidence of infectious diseases. Methotrexate has anti-inflammatory activity and immunosuppressive effects, and can reduce inflammation after spinal cord injury. To analyze gene expression changes and the molecular mechanism of methotrexate combined with methylprednisolone in the treatment of spinal cord injury, a rat model of spinal cord contusion was prepared using the PinPoint™ precision cortical impactor technique. Rats were injected with methylprednisolone 30 mg/kg 30 minutes after injury, and then subcutaneously injected with 0.3 mg/kg methotrexate 1 day after injury, once a day, for 2 weeks. TreadScan gait analysis found that at 4 and 8 weeks after injury, methotrexate combined with methylprednisolone significantly improved hind limb swing time, stride time, minimum longitudinal deviation, instant speed, footprint area and regularity index. Solexa high-throughput sequencing was used to analyze differential gene expression. Compared with methylprednisolone alone, differential expression of 316 genes was detected in injured spinal cord treated with methotrexate and methylprednisolone. The 275 up-regulated genes were mainly related to nerve recovery, anti-oxidative, anti-inflammatory and anti-apoptotic functions, while 41 down-regulated genes were mainly related to proinflammatory and pro-apoptotic functions. These results indicate that methotrexate combined with methylprednisolone exhibited better effects on inhibiting the activity of inflammatory cytokines and enhancing antioxidant and anti-apoptotic effects and thereby produced stronger neuroprotective effects than methotrexate alone. The 316 differentially expressed genes play an important role in the above processes.

Methylprednisolone exerts neuroprotective effects by regulating autophagy and apoptosis

Methylprednisolone markedly reduces autophagy and apoptosis after secondary spinal cord injury. Here, we investigated whether pretreatment of cells with methylprednisolone would protect neuron-like cells from subsequent oxidative damage via suppression of autophagy and apoptosis. Cultured N2a cells were pretreated with 10 µM methylprednisolone for 30 minutes, then exposed to 100 µM H₂O₂ for 24 hours. Inverted phase contrast microscope images, MTT assay, flow cytometry and western blot results showed that, compared to cells exposed to 100 µM H₂O₂ alone, cells pretreated with methylprednisolone had a significantly lower percentage of apoptotic cells, maintained a healthy morphology, and showed downregulation of autophagic protein light chain 3B and Beclin-1 protein expression. These findings indicate that methylprednisolone exerted neuroprotective effects against oxidative damage by suppressing autophagy and apoptosis.

Targeting the blood-spinal cord barrier: A therapeutic approach to spinal cord protection against ischemia-reperfusion injury

One of the principal functions of physical barriers between the blood and central nervous system protects system (i.e., blood brain barrier and blood-spinal cord barrier) is the protection from toxic and pathogenic agents in the blood. Disruption of blood-spinal cord barrier (BSCB) plays a key role in spinal cord ischemia-reperfusion injury (SCIRI). Following SCIRI, the permeability of the BSCB increases. Maintaining the integrity of the BSCB alleviates the spinal cord injury after spinal cord ischemia. This review summarizes current knowledge of the structure and function of the BSCB and its changes following SCIRI, as well as the prevention and cure of SCIRI and the role of the BSCB.

Methylprednisolone promotes recovery of neurological function after spinal cord injury: association with Wnt/β-catenin signaling pathway activation

Some studies have indicated that the Wnt/β-catenin signaling pathway is activated following spinal cord injury, and expression levels of specific proteins, including low-density lipoprotein receptor related protein-6 phosphorylation, β-catenin, and glycogen synthase kinase-3β, are significantly altered. We hypothesized that methylprednisolone treatment contributes to functional recovery after spinal cord injury by inhibiting apoptosis and activating the Wnt/β-catenin signaling pathway. In the current study, 30 mg/kg methylprednisolone was injected into rats with spinal cord injury immediately post-injury and at 1 and 2 days post-injury. Basso, Beattie, and Bresnahan scores showed that methylprednisolone treatment significantly promoted locomotor functional recovery between 2 and 6 weeks post-injury. The number of surviving motor neurons increased, whereas the lesion size significantly decreased following methylprednisolone treatment at 7 days post-injury. Additionally, caspase-3, caspase-9, and Bax protein expression levels and the number of apoptotic cells were reduced at 3 and 7 days post-injury, while Bcl-2 levels at 7 days post-injury were higher in methylprednisolone-treated rats compared with saline-treated rats. At 3 and 7 days post-injury, methylprednisolone up-regulated expression and activation of the Wnt/β-catenin signaling pathway, including low-density lipoprotein receptor related protein-6 phosphorylation, β-catenin, and glycogen synthase kinase-3β phosphorylation. These results indicate that methylprednisolone-induced neuroprotection may correlate with activation of the Wnt/β-catenin signaling pathway.

Protective effects of alpha lipoic acid on high glucose-induced neurotoxicity in PC12 cells

Hyperglycemia plays an important role in the development of diabetic neuropathy. In this study, we investigated the protective effects of alpha lipoic acid (ALA) against high glucose-induced neurotoxicity in PC12 cells as a suitable in vitro model for studying neuronal functions. PC12 cells were treated with high glucose (25 mg/ml for 24 h) in the absence and presence of ALA (100 μM for 24 h). The viability of PC12 cells was estimated by using MTT assay. The expression of pro- apoptotic Bax, anti- apoptotic Bcl-2 and caspase 3 protein were evaluated by western blotting. The reactive oxygen species (ROS) levels were determined with 2,7-dichlorodihydro- fluorescein diacetate (H2DCFDA). Biochemical markers of oxidative stress were assessed by using the total antioxidant power (TAP), lipid peroxidation (LPO), ADP/ATP ratio, activity of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). Pretreatment of PC12 cells with ALA, significantly improved high glucose-induced toxicity by increasing activity of antioxidant enzymes CAT and SOD in the PC12 cell. It also increased the concentrations of TAP. An elevated level of cell death and ROS in high glucose conditions, diminished with ALA treatment. Over expression of Bax and caspase 3 protein, elevation of ADP/ATP ratio and LPO level in high glucose- treated PC12 cells, were significantly reduced by ALA. It was concluded that ALA attenuates neurotoxicity induced by high glucose in PC12 cells.