Time-level relationship between indicators of oxidative stress and Glasgow Coma Scale scores of severe head injury patients

Cognitive Impairment Following Clinical or Recreational Use of Gammahydroxybutyric Acid (GHB): A Systematic Review

BACKGROUND

GHB (gamma-hydroxybutyric acid; sodium oxybate) is a general anaesthetic that is clinically used for the treatment of narcolepsy, cataplexy, alcohol withdrawal and alcohol relapse prevention. In addition, GHB is recreationally used. Most clinical and recreational users regard GHB as an innocent drug devoid of adverse effects, despite its high dependence potential and possible neurotoxic effects. At high doses, GHB may lead to a comatose state. This paper systematically reviews possible cognitive impairments due to clinical and recreational GHB use.

METHODS

PubMed and PsychINFO were searched for literature data about the acute and residual cognitive deficits following GHB use. This review is conducted using the PRISMA protocol.

RESULTS

A total of 43 reports covering human and animal data on GHB-induced cognitive impairments were eligible and reviewed. This systematic review found no indication for cognitive impairments after clinical GHB use. However, it supports the view that moderate GHB use may result in acute short-term cognitive impairments, whereas regular high-dose GHB use and/or multiple GHB-induced comas are probably neurotoxic resulting in long-term residual cognitive impairments.

CONCLUSION

These results emphasize the need for awareness among clinicians and recreational users to minimize negative health consequences of recreational GHB use, particularly when high doses are used and GHB-induced comas occur.

Effects of Recreational GHB Use and Multiple GHB-Induced Comas on Brain Structure and Impulsivity

BACKGROUND AND AIMS

The regular use of gamma-hydroxybutyrate acid (GHB) can induce GHB-induced comas. Other substance use disorders are associated with alterations in brain structure and impulsivity. Here we aim to investigate if these are also modulated by either regular GHB use or GHB-induced comas.

METHODS

In a sample of human males, structural and diffusion neuroimaging data were collected for 27 GHB users with ≥4 GHB-induced comas (GHB-Coma), 27 GHB users without GHB-induced comas (GHB-NoComa), and 27 polydrug users who never used GHB (No-GHB). The structural brain parameters were analyzed macroscopically using voxel-based morphometry and microscopically using tract-based spatial statistics (TBSS) and tractography. Impulsivity was assessed with the Barrat Impulsivity Scale.

RESULTS

In comparison to the other two groups, the GHB-Coma group showed a higher fractional anisotropy in the body of the corpus callosum and a lower mean diffusivity in the forceps minor (i.e., whole-brain TBSS analysis). No macrostructural differences nor microstructural differences, as assessed with tractography, were observed. The GHB-Coma group also reported higher impulsivity, which was more strongly associated with white matter volume and fractional anisotropy in tracts involved in impulse control (post-hoc analysis). GHB use per se was associated neither with differences in brain structure nor with impulsivity.

CONCLUSIONS

The results suggest that multiple GHB-induced comas, but not GHB use per se, are associated with microstructural alterations in white matter and with higher self-reported impulsivity, which in turn was associated with white matter tracts involved in impulse control.

Influence of Bone Marrow-Derived Mesenchymal Stem Cell Therapy on Oxidative Stress Intensity in Minimally Conscious State Patients

Neurological disorders, including minimally conscious state (MCS), may be associated with the presence of high concentrations of reactive oxygen species within the central nervous system. Regarding the documented role of mesenchymal stem cells (MSCs) in oxidative stress neutralization, the aim of this study is to evaluate the effect of bone marrow-derived MSC (BM-MSC) transplantation on selected markers of oxidative stress in MCS patients. Antioxidant capacity was measured in cerebrospinal fluid (CSF) and plasma collected from nine patients aged between 19 and 45 years, remaining in MCS for 3 to 14 months. Total antioxidant capacity, ascorbic acid and ascorbate concentrations, superoxide dismutase, catalase, and peroxidase activity were analyzed and the presence of tested antioxidants in the CSF and plasma was confirmed. Higher ascorbic acid (AA) content and catalase (CAT) activity were noted in CSF relative to plasma, whereas superoxide dismutase (SOD) activity and total antioxidant capacity were higher in plasma relative to CSF. Total antioxidant capacity measured in CSF was greater after BM-MSC transplantations. The content of ascorbates was lower and CAT activity was higher both in CSF and plasma after the administration of BM-MSC. The above results suggest that MSCs modulate oxidative stress intensity in MCS patients, mainly via ascorbates and CAT activity.

Demographic and Clinical Characteristics of Regular GHB-Users with and without GHB-Induced Comas

Gamma hydroxybutyric acid (GHB) has been used recreationally for nearly three decades and its chronic use is frequently associated with serious adverse events including GHB-intoxication with GHB-induced comas. Moreover, despite its low prevalence, the number of individuals with GHB-use disorders is steadily increasing. However, the risk-factors associated with chronic GHB-use or the development of a GHB-use disorders remain poorly understood. Purpose: This study aims to profile two types of GHB-users, those with and those without GHB-induced comas. Methods: We included 27 GHB users with ≥4 GHB-induced comas (GHB-Coma), 27 GHB users without a coma (GHB-NoComa), and 27 polydrug users who never used GHB (No-GHB). Participants completed self-reported questionnaires in order to assess their demographic and clinical features, and their use profile of GHB and other drugs. Results: The typical GHB user in our sample was young, single, living alone, well-educated, and a student. The GHB-Coma group had lower self-control and reported higher negative affect than the GHB-NoComa group. GHB-Coma participants were heavier GHB users and mostly used GHB alone at home, whereas the GHB-NoComa group mostly used GHB with friends and in nightclubs. Remarkably, the majority of participants were not concerned about potential neurocognitive impairments induced by GHB-intoxication and/or GHB-induced comas. Conclusion: In this assessment, different profiles for recreational users with and without GHB-induced comas were well expressed. Their description contributes to a better understanding of the risk factors associated with recreational GHB-use, GHB-induced coma, and the development of GHB-use disorders.

Influence of Gamma-Hydroxybutyric Acid-Use and Gamma-Hydroxybutyric Acid-Induced Coma on Affect and the Affective Network

BACKGROUND

Gamma-hydroxybutyric acid (GHB) is a drug of abuse associated with increased emergency room attendances, due to GHB-induced comas. Withdrawal from GHB often increases social anxiety and is linked to alterations in emotion processing. However, little is known about the effects of GHB-use and GHB-induced comas on affect regulation in humans.

OBJECTIVES

We aimed to assess the effect of GHB-use and GHB-induced comas on the affective network.

METHOD

We recruited 27 GHB users with ≥4 GHB-induced comas (GHB-Coma), 27 GHB users without a GHB-induced coma (GHB-NoComa), and 27 polydrug users who never used GHB (No-GHB). Participants completed self-report questionnaires assessing negative affect (depression, anxiety and stress) and performed an emotional face matching task during functional magnetic resonance imaging to probe activity of the amygdala and the hippocampus.

RESULTS

The GHB-Coma group reported higher levels of depression, anxiety, and stress; showed decreased activity of the hippocampus; and increased functional connectivity of the left hippocampus with the left fusiform gyrus and a cluster on the left temporal-parietal-occipital junction, when compared with the 2 other groups. The GHB-NoComa group showed decreased functional connectivity of the left hippocampus with the amygdala in comparison with the No-GHB group.

CONCLUSIONS

GHB-use but in particular GHB-induced comas, are associated with altered emotion identification and hippocampal functioning. Awareness campaigns are required to raise consciousness about the adverse effects of GHB-induced comas on affect regulation, despite the absence of subjective side effects.

Adverse effects of GHB-induced coma on long-term memory and related brain function

BACKGROUND

Gamma-Hydroxybutyric acid (GHB) is a drug of abuse associated with increasing numbers of GHB-dependent patients and emergency attendances often related to GHB-induced coma. Animal studies suggest that GHB induces oxidative stress in the hippocampus, resulting in memory impairments. However, the consequences of chronic GHB use and GHB-induced coma on human brain function and cognition are unknown.

METHODS

We recruited 27 GHB users with ≥4 GHB-induced comas (GHB-Coma), 27 GHB users without a coma (GHB-NoComa), and 27 polydrug users who never used GHB (No-GHB). Participants completed verbal and spatial memory tests and an associative memory encoding task during functional magnetic resonance imaging (fMRI) to probe hippocampus functioning.

RESULTS

The GHB-Coma group showed a lower premorbid IQ (p = 0.006) and performed worse on the verbal memory test (p = 0.017) compared to the GHB-NoComa group, despite exhibiting similar levels of education. Compared with the other two groups, the GHB-Coma group showed lower left hippocampus (p_SVC = 0.044) and left lingual gyrus (p_FWE = 0.017) activity, and a trend for lower hippocampal functional connectivity with the left superior temporal cortex during performance of the associative memory encoding task (p_FWE = 0.063). No significant differences were observed between the GHB-NoComa group and the No-GHB group.

CONCLUSIONS

These results suggest that multiple GHB-induced comas, but not the use of GHB per se, are associated with alterations of memory performance and memory-related brain, although no causal link can be inferred from this cross-sectional study. The results highlight the need for public awareness to minimize the negative health consequences of recreational GHB use, in particular when related with GHB-induced comas.

Novel therapeutic strategies for traumatic brain injury: acute antioxidant reinforcement

Traumatic brain injury (TBI) is the most important cause of disability in individuals under the age of 45 years and thus represents a significant social and economic burden. Evidence strongly suggests that oxidative stress is a cornerstone event leading to and propagating secondary injury mechanisms such as excitotoxicity, mitochondrial dysfunction, apoptosis, autophagy, brain edema, and inflammation. TBI has defied conventional approaches to diagnosis and therapy development because of its heterogeneity and complexity. Therefore, it is necessary to explore alternative approaches to therapy development for TBI. The aim of this review is to present a therapeutic approach for TBI, taking into account the evidence supporting the role for oxidative stress in the pathophysiological processes of secondary brain injury. The role of agents such as mitochondria-targeted antioxidants (melatonin and new mitochondria-targeted antioxidants), nicotinamide adenine dinucleotide phosphate (NADPH) inhibitors (antioxidant vitamins and apocynin), and other compounds having mainly antioxidant properties (hydrogen-rich saline, sulforaphane, U-83836E, omega-3, and polyphenols) is covered. The rationale for innovative antioxidant therapies based on current knowledge and particularly the most recent studies regarding this field is discussed. Particular considerations and translational potential of new TBI treatments are examined and a novel therapeutic proposal for TBI is presented.

Perspectives on molecular biomarkers of oxidative stress and antioxidant strategies in traumatic brain injury

Traumatic brain injury (TBI) is frequently associated with abnormal blood-brain barrier function, resulting in the release of factors that can be used as molecular biomarkers of TBI, among them GFAP, UCH-L1, S100B, and NSE. Although many experimental studies have been conducted, clinical consolidation of these biomarkers is still needed to increase the predictive power and reduce the poor outcome of TBI. Interestingly, several of these TBI biomarkers are oxidatively modified to carbonyl groups, indicating that markers of oxidative stress could be of predictive value for the selection of therapeutic strategies. Some drugs such as corticosteroids and progesterone have already been investigated in TBI neuroprotection but failed to demonstrate clinical applicability in advanced phases of the studies. Dietary antioxidants, such as curcumin, resveratrol, and sulforaphane, have been shown to attenuate TBI-induced damage in preclinical studies. These dietary antioxidants can increase antioxidant defenses via transcriptional activation of NRF2 and are also known as carbonyl scavengers, two potential mechanisms for neuroprotection. This paper reviews the relevance of redox biology in TBI, highlighting perspectives for future studies.

Relationship between markers of lipid peroxidation, thiol oxidation and Glasgow coma scale scores of moderate head injury patients in the 7 day post-traumatic period

OBJECTIVE

Epidemiologic works reveal that moderate head injury (MHI) is more frequent and a substantial number of these patients develop complications resulting in neurological disabilities. Reactive oxygen species (ROS) play a major role in post-traumatic neuronal damage following traumatic head injury. Thus, the current study analysed the post-traumatic changes in the erythrocyte markers of oxidative damage and the relationship between these parameters and Glasgow coma scale (GCS) scores of MHI patients during the 7 day study period.

METHODS

Peripheral venous blood samples were taken at the time of hospital admission (d1 of injury) and on d7 from 25 MHI patients (admission GCS score > 8). These were compared with samples from 25 healthy individuals (normal controls, NC). GCS scores were recorded at the same time points of the study period. Erythrocyte lipid peroxidation (LP) and thiol oxidation levels were estimated and compared with that of NC. The relationship between GCS scores and erythrocyte markers were also studied.

RESULTS

Erythrocyte thiobarbituric acid reactive substance (TBARS) levels reflecting lipid peroxidative damage remained significantly elevated at both time points of the study period in MHI patients as compared to NC (p < 0.001 ). There was a significant decrease in the level of nonprotein thiols in MHI patients as compared to NC (p < 0.01) at the same time points of the study. However, on d7 there were no further significant changes in the markers of oxidative damage in MHI patients as compared to on d1.

CONCLUSION

These findings suggest that a condition of oxidative stress occurs during the entire post-traumatic period in MHI patients and the utility of markers of oxidative damage in the prognosis of head injury needs to be addressed in further works.

Effects of electrical cervical spinal cord stimulation on cerebral blood perfusion, cerebrospinal fluid catecholamine levels, and oxidative stress in comatose patients

OBJECTIVES

Electrical spinal cord stimulation (SCS) is used to treat of chronic pain, obstructive arterial-related ischemia, and anginal pain. This study investigated cerebral blood perfusion, cerebrospinal fluid (CSF) catecholamine levels, and oxidative stress before and after cervical SCS in comatose patients.

METHODS

We evaluated cerebral blood perfusion, catecholamine (dopamine, norepinephrine, and epinephrine) levels, and oxidative stress in 20 comatose patients before and after SCS. After SCS for six months, cerebral blood perfusion (SPECT index, 2.293 +/- 0.255 vs. 2.779 +/- 0.209, p < 0.001), dopamine (49.0 +/- 12.1 vs. 198.9 +/- 62.6, p = 0.025), and norepinephrine (197.6 +/- 62.9 vs. 379.6 +/- 52.6, p = 0.021) but not epinephrine were significantly increased. Moreover, superoxide free radicals in whole blood were significantly decreased (210,079 +/- 47,763 vs. 109,212 +/- 20,086, p = 0.011) after SCS. Nine patients recovered from the consciousness within 71-287 days.

CONCLUSIONS

Increase of cerebral blood perfusion and catecholamines (dopamine and norepinephrine) in CSF after SCS was observed, whereas epinephrine level was unchanged. The superoxide free radicals were decreased after SCS. The results suggest that SCS increases cerebral blood perfusion, attenuates oxidative stress and increases biogenic amines in comatose patients.

Relationship between neurological outcome and early oxidative changes in erythrocytes in head injury patients

BACKGROUND

Experimental data indicate that destructive oxidative events reach their peak within the first 24 h after trauma in head injury (HI) and that brain damage occurring due to this impact can be the cause of death or irreversible permanent disabilities in affected patients.

METHODS

Venous blood samples were obtained from 50 HI patients within 24 h of trauma onset and from 30 age- and sex-matched normal controls (NC). Patients were divided into three different neurological outcome groups: those who died within 10 days of trauma (D), and those with severe neurological deficits (SD) or mild/no neurological deficits (MD) at 90 days after trauma. Early oxidative changes in erythrocytes were assessed by estimating an indicator of lipid peroxidative damage - thiobarbituric acid-reactive substances (TBARS) - and antioxidants [reduced glutathione (GSH) levels and superoxide dismutase (SOD) activity].

RESULTS

In the D group, erythrocyte TBARS levels were significantly higher compared to the NC, SD and MD groups (p<0.001); GSH levels were significantly lower compared to the NC (p<0.001) and MD (p<0.01) groups and SOD activity was significantly higher than in the NC (p<0.01) and MD (p<0.01) groups. In the SD group, TBARS levels were significantly higher than in the NC (p<0.001) and MD (p<0.05) groups; GSH levels were significantly lower than in the NC (p<0.001) and MD (p<0.01) groups and SOD activity was higher compared to the NC and MD (p<0.01) groups. In the MD group, TBARS levels were significantly higher and GSH levels significantly lower compared to the NC group (p<0.001). However, we did not observe any significant change in SOD activity compared to the NC group.

CONCLUSIONS

These findings indicate that early oxidative changes may reflect the severity of neurological insult and provide an early indication of patient outcome in traumatic HI.