Serum oxidative stress influences neurological recovery after surgery to treat acutely worsening symptoms of compression myelopathy: a cross-sectional human study

Abstract

BackgroundRecent reports indicate that oxidative stress induced by reactive oxygen species is associated with the pathobiology of neurodegenerative disorders that involve neuronal cell apoptosis. Here we conducted a cross-sectional study to evaluate serum levels of oxidative stress in cervical compression myelopathy.MethodsThirty-six serum samples were collected preoperatively from patients treated for acutely worsening compression myelopathy (AM) and chronic compression myelopathy (CM). Serum levels of oxidative stress markers were evaluated by measuring derivatives of reactive oxygen metabolites (ROM), which reflect concentrations of hydroperoxides. ROM in healthy individuals range from 250 to 300 (U. CARR), whereas ROM >340–400 and > 400 define moderate and severe levels of oxidative stress, respectively. Difference of ROM by the cause of disorders whether cervical spondylotic myelopathy (CSM) or cervical ossification of longitudinal ligament (OPLL), correlations between ROM and patient age, body mass index (BMI), history of smoking, existence of diabetes were examined. Neurological evaluations according to Japanese Orthopaedic Association (JOA) scores were performed and correlated with ROM.ResultsROM increased to 349.5 ± 54.8, representing a moderate oxidative stress, in CM samples. ROM increased to 409.2 ± 77.9 in AM samples, reflecting severe oxidative stress which were significantly higher than for CM samples (p < 0.05). There was no significant difference by the cause of disorders (CSM or OPLL). ROM were significantly increased in AM serum samples from female patients versus AM male and CM patients (p < 0.05). There were no correlations between ROM and age, BMI, history of smoking, and existence of diabetes. A negative correlation between ROM and recovery rate of JOA score (R2 = 0.454, p = 0.047) was observed in the AM group.ConclusionsAlthough moderate oxidative stress was present in patients with CM, levels of oxidative stress increased in severity in patients with AM. These results suggest that postsurgical neurological recovery is influenced by severe oxidative stress in AM.

Time Course of Changes in Serum Oxidative Stress Markers to Predict Outcomes for Surgical Treatment of Lumbar Degenerative Disorders

“…Markers of oxidative stress were previously shown to increase with increasing age, and higher levels were also associated with female gender, obesity, smoking, and diabetes as well as with endogenous oxidative stress [ 10 , 20 ]. Here, we showed that levels of ROM were increased in females, a finding that is in part consistent with that of a previous study [ 8 ]. However, there was no significant correlation between ROM levels and age, BMI, smoking status, and diabetes.…”

“…These endogenous factors may not have a substantial relationship with ROM at least in lumbar degenerative disorders like LSS or LDH. Meanwhile, the level of oxidative stress based on serum analyses was shown to increase in patients with acute spinal cord injury, compression myelopathy, Alzheimer's disease, amyotrophic lateral sclerosis, or Parkinson's disease [ 4 – 8 ]. Reports of oxidative stress in the presence of neurodegenerative diseases suggest the involvement of neuronal cell apoptosis.…”

“…For patients who exhibited oxidative stress, ROS produced in serum could be measured in terms of ROM levels. The normal range for ROMs is typically 250–300 U.CARR, whereas ROM levels for moderate and severe oxidative stress corresponded to >340–400 U.CARR and >400 U.CARR, respectively [ 8 , 10 ]. All serum samples were collected during hematological examinations at about one month before surgery and at 3 months, 6 months, and 1 year after surgery.…”

“…Recent reports indicate that oxidative stress markers in serum are elevated in various neurodegenerative disorders such as Alzheimer's disease, amyotrophic lateral sclerosis, and Parkinson's disease [ 3 – 5 ]. For spinal lesions, levels of serum oxidative stress markers are elevated in patients with acute spinal cord injury or compression myelopathy [ 6 – 8 ]. In particular, a recent report indicated that increased amounts of serum oxidative stress influence neurological recovery after surgery and manifest as acute worsening of symptoms of cervical compression myelopathy [ 8 ].…”

“…For spinal lesions, levels of serum oxidative stress markers are elevated in patients with acute spinal cord injury or compression myelopathy [ 6 – 8 ]. In particular, a recent report indicated that increased amounts of serum oxidative stress influence neurological recovery after surgery and manifest as acute worsening of symptoms of cervical compression myelopathy [ 8 ]. However, to our knowledge, no studies have analyzed the time course of changes in serum oxidative stress markers before and after surgery in patients with lumbar degenerative disorders.…”