Serum cholesterol, uric acid and cholinesterase in victims of the Tokyo subway sarin poisoning: a relation with post-traumatic stress disorder

Physiological response of roe deer (Capreolus capreolus) during stalking hunts depending on age

BACKGROUND

The European roe deer (Capreolus capreolus) is a species particularly reactive to all kinds of negative stimuli. Hunting activity is one of the most potent stressors that disturbs the welfare of wild animals. During stress, various endocrine responses are elicited to improve the physical performance of the affected individual. A commonly assessed hormone for overcoming stressful situations is cortisol (CORT). In this study, plasma CORT levels in roe deer were assessed during the season of the most intense stalking hunts in Poland (summer vs. late autumn), the sex of the harvested animals (males vs. females), and age of harvest animal. In addition, the health status of the roe doe was evaluated on the basis of selected indices of blood chemistry, which could be associated with circulating cortisol levels.

RESULTS

The mean cortisol levels were 58.066 ng/ml in the male group (summer) and 27.694 ng/ml in the female group (late autumn). Higher CORT levels were associated with a significantly lower of total cholesterol, lactate dehydrogenase, and uric acid (p < 0.05). Moreover, the mean concentration of uric acid was negatively correlated with the level of CORT in the male and female groups (p < 0.05). Together with the increase in mean CORT level, the HDL cholesterol of all the tested animals increased significantly (p < 0.05).

CONCLUSIONS

Higher CORT in males during the summer than in females during the late autumn were most likely due to the arousal with the mating season. The level of CORT increased with the animals' age. Uric acid and age are both predictors of roe deer's serum CORT level.

Occupational Exposures and Environmental Health Hazards of Military Personnel

BACKGROUND

Military personnel are frequently exposed to environmental pollutants that can cause a variety of diseases.

METHODS

This review analyzed publications regarding epidemiological and biomonitoring studies on occupationally-exposed military personnel.

RESULTS

The exposures include sulfur mustard, organ chlorines, combustion products, fuel vapors, and ionizing and exciting radiations. Important factors to be considered are the lengths and intensities of exposures, its proximity to the sources of environmental pollutants, as well as confounding factors (cigarette smoke, diet, photo-type, healthy warrior effect, etc.). Assessment of environmental and individual exposures to pollutants is crucial, although often omitted, because soldiers have often been evaluated based on reported health problems rather than on excessive exposure to pollutants. Biomarkers of exposures and effects are tools to explore relationships between exposures and diseases in military personnel. Another observation from this review is a major problem from the lack of suitable control groups.

CONCLUSIONS

This review indicates that only studies which analyzed epidemiological and molecular biomarkers in both exposed and control groups would provide evidence-based conclusions on exposure and disease risk in military personnel.

A national toxicology program systematic review of the evidence for long-term effects after acute exposure to sarin nerve agent

Sarin is a highly toxic nerve agent that was developed for chemical warfare during World War II and is used in present conflicts. Immediate effects of acute sarin exposure are established; however, whether effects persist after initial signs have subsided is debated. The National Toxicology Program (NTP) conducted a systematic review to evaluate the evidence for long-term neurological effects following acute (<24 hour) exposure to sarin. The literature search and screening process identified 32 data sets within the 34 human studies and 47 data sets within the 51 animal studies (from 6837 potentially relevant references) that met the objective and the inclusion criteria. Four main health effect categories of neurological response were identified as having sufficient data to reach hazard conclusions: (1) cholinesterase levels; (2) visual and ocular effects; (3) effects on learning, memory, and intelligence; and (4) morphology and histopathology in nervous system tissues. NTP concluded that acute sarin exposure is known to be a neurological hazard to humans in the period following exposure up to 7 days and suspected to be a hazard week to years after exposure, given a lower level of evidence in later time periods. Effects included reduced cholinesterase, visual and ocular effects, impaired learning and memory, and altered nervous system morphology. Further mechanistic, targeted animal studies, translational research, and rapid research responses after human exposures may reduce uncertainties on long-term consequences of sarin.

The Tokyo subway sarin attack has long-term effects on survivors: A 10-year study started 5 years after the terrorist incident

Objectives

The Tokyo subway sarin attack in 1995 was an unprecedented act of terrorism that killed 13 people and sickened more than 6,000. The long-term somatic and psychological effects on its victims remain unknown.

Methods

We conducted analyses on the self-rating questionnaire collected annually by the Recovery Support Center (RSC) during the period from 2000 to 2009. The RSC is the only organization that has large-scale follow-up data about sarin attack victims. The prevalence of self-reported symptoms was calculated over 10 years. We also evaluated the prevalence of posttraumatic stress response (PTSR), defined as a score ≥ 25 on the Japanese-language version of the Impact of Event Scale–Revised. The multivariate Poisson regression model was applied to estimate the risk ratios of age, gender, and year factor on the prevalence of PTSR.

Results

Subjects were 747 survivors (12% of the total) who responded to the annual questionnaire once or more during the study period. The prevalence of somatic symptoms, especially eye symptoms, was 60–80% and has not decreased. PTSR prevalence was 35.1%, and again there was no change with time. The multivariate Poisson regression model results revealed “old age” and “female” as independent risk factors, but the passage of time did not decrease the risk of PTSR.

Conclusions

Although symptoms in most victims of the Tokyo subway sarin were transient, this large-scale follow-up data analysis revealed that survivors have been suffering from somatic and psychological long-term effects.

Interplays of estrogen receptor alpha gene rs2234693 with post-traumatic stress disorder influence serum glucose and lipids profiles in Chinese adolescents

Both post-traumatic stress disorder (PTSD) and estrogen receptor alpha (ESR1) gene rs2234693 were reported to influence serum glucose and lipids profiles. However, their interactions on serum glucose and lipids profiles have not been reported. A total of 708 Chinese Han high school students were recruited at 6th months after the 2008 Wenchuan Earthquake. Serum concentrations of fasting blood glucose (FBG), fasting blood insulin (FBI), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were detected. Body mass index (BMI) and homeostatic model assessment of insulin resistance (HOMA-IR) were calculated. PTSD was assessed by the PTSD Checklist Civilian Version (PCL-C). Variants of ESR1 rs2234693 was analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses and verified by DNA sequencing. The male subjects with PTSD had a trend of higher FBG (p = 0.077) and significantly higher FBI and HOMA-IR than male controls. The PTSD subjects had significantly higher levels of FBG, FBI, HOMA-IR and HDL-C than the controls only in the male C allele carriers irrespective of adjustment for age and BMI. In the male controls group, the C allele carriers had significantly lower HDL-C than the TT homozygotes regardless of adjustment for age and BMI. In female PTSD group, the C allele carriers had significantly higher TC/HDL-C and LDL-C/HDL-C than the TT homozygotes after adjustment for age and BMI. These results suggest the interplays of ESR1 rs2234693 with PTSD influence serum glucose and lipids profiles with a gender dependent manner.

Posttraumatic Stress Disorder Augments Plasma Triglycerides in TT Homozygotes of rs495225 at Growth Hormone Secretagogue Receptor Gene

Posttraumatic stress disorder (PTSD) and growth hormone secretagogue receptor (GHSR) were reported to be associated with plasma lipid and glucose levels. However, interplays of PTSD with GHSR on plasma lipid and glucose levels have not been explored yet. This study was to investigate the interplays of PTSD and GHSR rs495225 on plasma glucose and lipid profiles. A total of 709 high school students were recruited at 6 months after the 2008 Wenchuan earthquake. Variants of GHSR rs495225 were identified by polymerase chain reaction-restriction fragment length polymorphism analyses and verified by DNA sequencing. The PTSD Checklist Civilian Version (PCL-C) was used to assess PTSD. There was no significant difference of PTSD prevalence between the TT homozygotes and the C allele carriers. However, the students with PTSD had significantly lower levels of glucose, insulin and homeostasis model assessment of insulin resistance (HOMA-IR) than the students without PTSD in the C allele carriers of GHSR rs495225 after the adjustment for age, gender and body mass index (BMI), but higher levels of TG and TG/HDL-C in the TT homozygotes. Meanwhile, the TT homozygotes had lower levels of HDL-C than the C allele carriers in the students without PTSD, but higher levels of insulin and HOMA-IR in the subjects with PTSD. After the adjustment of age and gender, and additional adjustment for BMI, the results were not changed except the difference of insulin was only a tendency (p = 0.054) after the additional adjustment for BMI. PTSD may augment TG levels and the related lipid ratio TG/HDL-C in the TT homozygotes of GHSR rs495225 but decrease the levels of glucose, insulin and HOMA-IR in the C allele carriers.

Genetic Variants of the Brain-Derived Neurotrophic Factor and Metabolic Indices in Veterans With Posttraumatic Stress Disorder

Posttraumatic stress disorder (PTSD) is a trauma and stressor related disorder that may develop after exposure to an event that involved the actual or possible threat of death, violence or serious injury. Its molecular underpinning is still not clear. Brain-derived neurotrophic factor (BDNF) modulates neuronal processes such as the response to stress, but also weight control, energy and glucose homeostasis. Plasma BDNF levels and a functional BDNF Val66Met (rs6265) polymorphism were reported to be associated with PTSD, as well as with increased body mass index (BMI) and dyslipidaemia in healthy subjects and patients with cardio-metabolic diseases, but these results are controversial. The other frequently studied BDNF polymorphism, C270T (rs56164415), has been associated with the development of different neuropsychiatric symptoms/disorders. As far as we are aware, there are no data on the association of BDNF Val66Met and C270T polymorphisms with metabolic indices in PTSD. Due to high rates of obesity and dyslipidaemia in PTSD, the aim of this study was to elucidate the association of BDNF Val66Met and C270T polymorphisms with BMI and lipid levels in veterans with PTSD. We hypothesized that BDNF variants contribute to susceptibility to metabolic disturbances in PTSD. The study included 333 Caucasian males with combat related PTSD, diagnosed according to DSM-5 criteria. Genotyping of the BDNF Val66Met and C270T polymorphisms was performed using the real-time PCR method. Results were analyzed using hierarchical multiple linear regression and the Mann-Whitney test, with p-value corrected to 0.005. The results showed that BDNF Val66Met and BDNF C270T polymorphisms were not significantly associated with BMI, total cholesterol, LDL-cholesterol, HDL-cholesterol or triglycerides. Although the BDNF C270T polymorphism was nominally associated only with HDL-cholesterol in veterans with PTSD, this significance disappeared after controlling for the effect of age. Namely, slightly higher plasma HDL values in T allele carriers, compared to CC homozygotes, were associated with differences in age. Our results, controlled for the critical covariates, revealed that BDNF Val66Met and C270T were not significantly associated with metabolic indices in veterans with PTSD and that these genetic variants do not contribute to susceptibility to metabolic disturbances in PTSD.

Early changes in M2 muscarinic acetylcholine receptors (mAChRs) induced by sarin intoxication may be linked to long lasting neurological effects

The effect of sarin on the binding parameters (KD & Bmax) of M2 muscarinic acetylcholine receptor (mAChR) was studied 24h and 1 week post exposure. Male & female Sprague-Daweley rats were poisoned with 1XLD50 sarin (80μg/kg, im) followed by treatment of trimedoxime bromide and atropine (7.5:5mg/kg, im) 1min later. Brains were removed and analyzed for M2 mAChR binding, using [³H]AFDX384, an M2 selective antagonist. A significant increase in KD of M2 mAChR was found in the cortex 24h post poisoning, displaying elevation from 4.65±1.16 to 8.45±1.06nM and 5.24±0.93 to 9.29±1.56nM in male and female rats, respectively. A rise in KD was also noted 1 week following exposure from 5.04±1.20 to 11.75±2.78 and from 5.37±1.02 to 11.66±1.73nM, presenting an added increase of 51 and 40% (compared to 24h) in males and females, respectively. Analysis of M2 receptor density (Bmax) revealed a significant reduction of 68% in males and insignificant reduction of 22% in females, 24h after sarin exposure which was followed by 37% recovery in males and 100% recovery in females, 1 week later. These results indicate that sarin induces a long-term decreased affinity in M2 mAChR (elevated KDs) and a transient effect on the number of this receptor subtype (Bmax). We hypothesize that the reduced affinity of the M2 receptors (negative auto-regulatory receptors) may cause long-term brain deficits by impairing the normal regulation release of ACh into the synaptic cleft.

Cholinesterase reactivators and bioscavengers for pre- and post-exposure treatments of organophosphorus poisoning

Organophosphorus agents (OPs) irreversibly inhibit acetylcholinesterase (AChE) causing a major cholinergic syndrome. The medical counter-measures of OP poisoning have not evolved for the last 30 years with carbamates for pretreatment, pyridinium oximes-based AChE reactivators, antimuscarinic drugs and neuroprotective benzodiazepines for post-exposure treatment. These drugs ensure protection of peripheral nervous system and mitigate acute effects of OP lethal doses. However, they have significant limitations. Pyridostigmine and oximes do not protect/reactivate central AChE. Oximes poorly reactivate AChE inhibited by phosphoramidates. In addition, current neuroprotectants do not protect the central nervous system shortly after the onset of seizures when brain damage becomes irreversible. New therapeutic approaches for pre- and post-exposure treatments involve detoxification of OP molecules before they reach their molecular targets by administrating catalytic bioscavengers, among them phosphotriesterases are the most promising. Novel generation of broad spectrum reactivators are designed for crossing the blood-brain barrier and reactivate central AChE. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.

Just World Beliefs Are Associated With Lower Levels of Metabolic Risk and Inflammation and Better Sleep After an Unfair Event

This study's goal was to conduct a preliminary test of the theory that just world beliefs can buffer against negative physiological outcomes after people experience certain types of negative life events by testing associations between just world beliefs and physiological outcomes among people with different life event histories. In a sample of 247 adults (M_age  = 46.01; 24.31% men; 60.78% White), this research investigated the relationship between just world beliefs and metabolic symptoms, inflammation, and sleep among people who had recently experienced an unfair event, another type of negative event, or no negative event. Stronger just world beliefs correlated with lower metabolic risk, lower inflammation, and better sleep among people who had recently experienced an unfair event, but not among those in the other two event groups. These findings suggest that people's beliefs about the world may interact with their life experiences in ways that have implications for health-relevant outcomes.

Metabolic risk factors and posttraumatic stress disorder: the role of sleep in young, healthy adults

OBJECTIVE

Posttraumatic stress disorder (PTSD) is associated with indicators of poor physical health and sleep disturbance. This study investigated the relationship between PTSD and metabolic risk factors and examined the role of sleep duration in medically healthy and medication-free adults.

METHODS

Participants with PTSD (n = 44, mean age = 30.6 years) and control participants free of lifetime psychiatric history (n = 50, mean age = 30.3 years) recorded sleep using sleep diary for 10 nights and actigraphy for 7 nights. We assessed metabolic risk factors including fasting triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein cholesterol, as well as abdominal fat using dual-energy x-ray absorptiometry.

RESULTS

PTSD was associated with shorter sleep duration (based on self-report, not actigraphy) and higher metabolic risks (controlling for body fat percentage), including increased triglycerides (p = .03), total cholesterol (p < .001), LDL cholesterol (p = .006), very low density lipoprotein cholesterol (p = .002), and cholesterol/high-density lipoprotein ratio (p = .024). In addition, sleep duration was associated with metabolic risks in PTSD (significant correlations ranged from r = -0.20 to r = -0.40) but did not fully account for the association between PTSD and metabolic measures.

CONCLUSIONS

Metabolic risk factors are associated with PTSD even in early adulthood, which highlights the need for early intervention. Future longitudinal research should assess whether sleep disturbance in PTSD is a mechanism that contributes to heightened metabolic risk to elucidate the pathway from PTSD to higher rates of medical disorders such as obesity, diabetes, and heart disease.

Circulating levels of hormones, lipids, and immune mediators in post-traumatic stress disorder - a 3-month follow-up study

A number of peripheral blood analytes have been proposed as potential biomarkers of post-traumatic stress disorder (PTSD). Few studies have investigated whether observed changes in biomarkers persist over time. The aim of this study was to investigate the association of combat-related chronic PTSD with a wide array of putative PTSD biomarkers and to determine reliability of the measurements, i.e., correlations over time. Croatian combat veterans with chronic PTSD (n = 69) and age-matched healthy controls (n = 32), all men, were assessed at two time points separated by 3 months. Serum levels of lipids, cortisol, dehydroepiandrosterone-sulfate (DHEA-S), prolactin, and C-reactive protein were determined. Multiplex assay was used for the simultaneous assessment of 13 analytes in sera: cytokines [interferon-γ, interleukin (IL)-1β, IL-2, IL-4, IL-6, TNF-α], adhesion molecules (sPECAM-1, sICAM-1), chemokines (IL-8 and MIP-1α), sCD40L, nerve growth factor, and leptin. Group differences and changes over time were tested by parametric or non-parametric tests, including repeated measures analysis of covariance. Reliability estimates [intraclass correlation coefficient (ICC) and kappa] were also calculated. Robust associations of PTSD with higher levels of DHEA-S [F(1,75) = 8.14, p = 0.006)] and lower levels of prolactin [F(1,75) = 5.40, p = 0.023] were found. Measurements showed good to excellent reproducibility (DHEA-S, ICC = 0.50; prolactin, ICC = 0.79). Serum lipids did not differ between groups but significant increase of LDL-C after 3 months was observed in the PTSD group (t = 6.87, p < 0.001). IL-8 was lower in the PTSD group (t = 4.37, p < 0.001) but assessments showed poor reproducibility (ICC = -0.08). Stable DHEA-S and prolactin changes highlight their potential to be reliable markers of PTSD. Change in lipid profiles after 3 months suggests that PTSD patients may be more prone to hyperlipidemia. High intra-individual variability in some variables emphasizes the importance of longitudinal studies in investigations of PTSD biomarkers.

The role of high-density lipoprotein cholesterol in risk for posttraumatic stress disorder: taking a nutritional approach toward universal prevention

Several cross-sectional studies, but no prospective studies, have reported an association between an abnormal lipid profile and posttraumatic stress disorder (PTSD). We hypothesized that an abnormal lipid profile might predict risk for developing PTSD. In this prospective study, we analyzed data from 237 antidepressant-naïve severely injured patients who participated in the Tachikawa Cohort of Motor Vehicle Accident Study. High-density lipoprotein cholesterol (HDL-C) levels at baseline were significantly lower in patients with PTSD than those without PTSD at 6 months after motor vehicle accident (MVA) and were inversely associated with risk for PTSD. In contrast, triglycerides (TG) at baseline were significantly higher in patients with PTSD than in those without PTSD at 6 months post-MVA and were positively associated with risk for PTSD. There was no clear association between low-density lipoprotein cholesterol or total cholesterol and risk for PTSD. In conclusion, low HDL-C and high TG may be risk factors for PTSD. Determining lipid profiles might help identify those at risk for PTSD after experiencing trauma.

Molecular evidence of stress-induced acute heart injury in a mouse model simulating posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is a common condition induced by life-threatening stress, such as that experienced by soldiers under battlefield conditions. Other than the commonly recognized behavioral and psychological dysfunction, epidemiological studies have also revealed that PTSD patients have a higher risk of other diseases, such as cardiovascular disorders. Using a PTSD mouse model, we investigated the longitudinal transcriptomic changes in heart tissues after the exposure to stress through intimidation. Our results revealed acute heart injury associated with the traumatic experience, reflecting the underlying biological injury processes of the immune response, extracellular matrix remodeling, epithelial-to-mesenchymal cell transitions, and cell proliferation. Whether this type of injury has any long-term effects on heart function is yet to be determined. The differing responses to stress leading to acute heart injury in different inbred strains of mice also suggest that this response has a genetic as well as an environmental component. Accordingly, the results from this study suggest a molecular basis for the observed higher risk of cardiovascular disorders in PTSD patients, which raises the likelihood of cardiac dysfunction induced by long-term stress exposures.

Associations of serum uric acid and SLC2A9 variant with depressive and anxiety disorders: a population-based study

BACKGROUND

Limited information exists regarding the association between serum uric acid (SUA) and psychiatric disorders. We explored the relationship between SUA and subtypes of major depressive disorder (MDD) and specific anxiety disorders. Additionally, we examined the association of SLC2A9 rs6855911 variant with anxiety disorders.

METHODS

We conducted a cross-sectional analysis on 3,716 individuals aged 35-66 years previously selected for the population-based CoLaus survey and who agreed to undergo further psychiatric evaluation. SUA was measured using uricase-PAP method. The French translation of the semi-structured Diagnostic Interview for Genetic Studies was used to establish lifetime and current diagnoses of depression and anxiety disorders according to the DSM-IV criteria.

RESULTS

Men reported significantly higher levels of SUA compared to women (357±74 µmol/L vs. 263±64 µmol/L). The prevalence of lifetime and current MDD was 44% and 18% respectively while the corresponding estimates for any anxiety disorders were 18% and 10% respectively. A quadratic hockey-stick shaped curve explained the relationship between SUA and social phobia better than a linear trend. However, with regards to the other specific anxiety disorders and other subtypes of MDD, there was no consistent pattern of association. Further analyses using SLC2A9 rs6855911 variant, known to be strongly associated with SUA, supported the quadratic relationship observed between SUA phenotype and social phobia.

CONCLUSIONS

A quadratic relationship between SUA and social phobia was observed consistent with a protective effect of moderately elevated SUA on social phobia, which disappears at higher concentrations. Further studies are needed to confirm our observations.

Absence of tolerance to the anticonvulsant and neuroprotective effects of imidazenil against DFP-induced seizure and neuronal damage

The clinical use of diazepam or midazolam to control organophosphate (OP) nerve agent-induced seizure activity is limited by their unwanted effects including sedation, amnesia, withdrawal, and anticonvulsant tolerance. Imidazenil is an imidazo-benzodiazepine derivative with high intrinsic efficacy and selectivity for α2-, α3-, and α5- but low intrinsic efficacy for α1-containing GABA(A) receptors. We have previously shown that imidazenil is more efficacious than diazepam at protecting rats and mice from diisopropyl fluorophosphate (DFP)-induced seizures and neuronal damage without producing sedation. In the present study, we compared the tolerance liability of imidazenil and diazepam to attenuate the seizure activity and neurotoxic effects of DFP. Rats received protracted (14 days) oral treatment with increasing doses of imidazenil (1-4 mg/kg), diazepam (5-20 mg/kg), or vehicle. Eighteen hours after the last dose of the protracted treatment schedule, rats were tested for anticonvulsant tolerance after a 30 min pretreatment with a single test dose of imidazenil (0.5 mg/kg) or diazepam (5 mg/kg) prior to a DFP challenge (1.5 mg/kg). The anticonvulsant (modified Racine score scale) and neuroprotective (fluoro-jade B staining) effects of diazepam were significantly reduced in protracted diazepam-treated animals whereas the effects of imidazenil were not altered in protracted imidazenil-treated animals. The present findings indicate that protracted imidazenil treatment does not produce tolerance to its protective action against the neurotoxic effects of OP exposure.

Evolution of and perspectives on therapeutic approaches to nerve agent poisoning

After more than 70 years of considerable efforts, research on medical defense against nerve agents has come to a standstill. Major progress in medical countermeasures was achieved between the 50s and 70s with the development of anticholinergic drugs and carbamate-based pretreatment, the introduction of pyridinium oximes as antidotes, and benzodiazepines in emergency treatments. These drugs ensure good protection of the peripheral nervous system and mitigate the acute effects of exposure to lethal doses of nerve agents. However, pyridostigmine and cholinesterase reactivators currently used in the armed forces do not protect/reactivate central acetylcholinesterases. Moreover, other drugs used are not sufficiently effective in protecting the central nervous system against seizures, irreversible brain damages and long-term sequelae of nerve agent poisoning.New developments of medical counter-measures focus on: (a) detoxification of organophosphorus molecules before they react with acetylcholinesterase and other physiological targets by administration of stoichiometric or catalytic scavengers; (b) protection and reactivation of central acetylcholinesterases, and (c) improvement of neuroprotection following delayed therapy.Future developments will aim at treatment of acute and long-term effects of low level exposure to nerve agents, research on alternative routes for optimizing drug delivery, and therapies. Though gene therapy for in situ generation of bioscavengers, and cell therapy based on neural progenitor engraftment for neuronal regeneration have been successfully explored, more studies are needed before practical medical applications can be made of these new approaches.

Deterioration in brain and heart functions following a single sub-lethal (0.8 LCt50) inhalation exposure of rats to sarin vapor: a putative mechanism of the long term toxicity

The main injuries among victims of the terrorist act in the Tokyo subway resulted from sub-lethal inhalation and whole body exposure to sarin vapor. In order to study the long term effects of such exposure and to simulate these conditions, freely moving rats were exposed to sarin vapor (27.2±1.7 μg/l) for 10 min. About 50% of the rats showed no overt symptoms and the rest had mild to moderate clinical symptoms that subsided within 4h following exposure. A reduction of weight was noted during the first 3 days with full recovery on the 4th day. Rat's heart was challenged with epinephrine 1 and 6 months post exposure. A significant reduction in the threshold for epinephrine-induced arrhythmia (EPIA) was noted in rats exposed to sarin. A time dependent increase in the kD and Bmax values of muscarinic auto receptors (M2) was recorded in the rat's cortex and striatum. No changes were recorded in the rats' brain trans locator protein (TSPO) levels, concomitant with no observed changes in the animals' performance in A Morris water maze test. A significant increase in open field activity was noted 6 months following exposure to sarin vapor as well as a significant decrease in prostaglandin E₂ (PGE₂) production in the brain. It is speculated that down regulation of the M2 auto receptor function, caused hyper reactivity of the cholinergic system which leads to the changes described above. The continuous reduction in M2 auto-receptor system through an unknown mechanism may be the cause for long lasting decline in sarin-exposed casualties' health.

Acute imidazenil treatment after the onset of DFP-induced seizure is more effective and longer lasting than midazolam at preventing seizure activity and brain neuropathology

Diazepam (DZ), the preferred anticonvulsant benzodiazepine (BZ) for the treatment of organophosphate (OP) nerve agent-induced seizures and neuronal damage, has been associated with unwanted effects such as sedation, amnesia, cardiorespiratory depression, anticonvulsant tolerance, and dependence liability. In a search for safer and more effective anticonvulsant BZs against OP-induced seizure and neuronal damage, we have previously shown that imidazenil (IMD), a low-intrinsic efficacy positive allosteric modulator of gamma-aminobutyric acid (GABA) action at α1-containing GABA(A) receptors, which has high intrinsic efficacy at α2-, α3-, and α5-containing GABA(A) receptors, is more potent and longer lasting than DZ pretreatment at protecting rats from diisopropyl fluorophosphate (DFP)-induced electrocorticographic (ECoG) seizures and neuronal damage. The effects of IMD were observed at doses that are devoid of sedative, amnestic, and anticonvulsant tolerance actions. In the present study, we compared the anticonvulsant and neuroprotective effects of a combination of atropine (2 mg/kg, ip) and pyridine-2-aldoxime methochloride (2-PAM, 20 mg/kg, ip) with IMD (0.5 mg/kg, ip) or midazolam (MDZ, 0.5-2 mg/kg, ip) administered after the onset of DFP (1.5 mg/kg, sc)-induced seizure activity. The severity of DFP-induced ECoG seizures was assessed by continuous radio telemetry recordings in unrestrained and freely moving rats. Furthermore, the extent of neuronal damage was evaluated using a neuron-specific nuclear protein immunolabeling and fluoro-jade B staining procedure. We report here that IMD is more efficacious and longer lasting than sedating doses of MDZ in protecting rats from DFP-induced ECoG seizures and neuronal damage.

Posttraumatic stress disorder and dyslipidemia: previous research and novel findings from patients with PTSD caused by myocardial infarction

OBJECTIVES

Based on a brief systematic review suggesting dyslipidemia in posttraumatic stress disorder (PTSD), we studied, for the first time, levels of blood lipids in patients with a DSM-IV diagnosis of PTSD caused by myocardial infarction (MI).

METHODS

Study participants were eight patients with full PTSD, eight patients with subsyndromal PTSD, and 31 patients with no PTSD who were diagnosed using the Clinician-Administered PTSD Scale (CAPS) interview after a mean of 32+/-8 months after MI. Levels of total cholesterol, low-density lipoprotein-cholesterol, triglycerides, and high-density lipoprotein-cholesterol (HDL-C) were determined in plasma.

RESULTS

Patients with full PTSD had lower HDL-C than patients with subsyndromal PTSD (P = 0.044) and those with no PTSD (P = 0.014) controlling for sex, body mass index, and statin equivalent dosage. Moreover, HDL-C levels were inversely associated with PTSD total symptoms (r = -0.33, P = 0.027), re-experiencing symptoms (r = -0.32, P = 0.036), and avoidance symptoms (r = -0.34, P = 0.025). There were no significant associations of PTSD diagnostic status and symptomatology with the three other lipid measures.

CONCLUSION

Chronic PTSD caused by MI was associated with lower plasma levels of HDL-C. The finding concurs with the notion of dyslipidemia partially underlying the atherosclerotic risk in individuals with PTSD caused by different types of trauma.

Abnormal serum lipid profile in Brazilian police officers with post-traumatic stress disorder

BACKGROUND

To measure the serum lipid composition of a sample of Brazilian police officers with and without PTSD regularly exposed to potentially traumatic situations.

METHODS

A cross-sectional survey was conducted with 118 active duty male police officers. Serum concentrations for total cholesterol, LDL-C, HDL-C, and triglycerides were enzymatically determined. Body mass index (BMI) was obtained for each participant.

RESULTS

Officers with PTSD exhibited significantly higher serum total cholesterol, LDL-C and triglycerides levels than those without PTSD. Total cholesterol and triglycerides, but not LDL-C, remained associated with PTSD diagnosis after controlling for confounding influences (i.e. socio-demographics, BMI, and tobacco, alcohol and medication use).

LIMITATIONS

The sample size was small. A nutritional interview was employed instead of established scales to assess alimentary habits, tobacco or alcohol consumption. A self-report screening tool was used to assess the prevalence of PTSD.

CONCLUSIONS

The association between PTSD and abnormal serum lipid profile and a tendency to exhibit higher BMI suggests that individuals with PTSD may be at increased risk for developing metabolic syndrome, a condition that by itself could account for many of the most serious PTSD-related physical health problems.

Human brain structural change related to acute single exposure to sarin

OBJECTIVE

This study aimed to identify persistent morphological changes subsequent to an acute single-time exposure to sarin, a highly poisonous organophosphate, and the neurobiological basis of long-lasting somatic and cognitive symptoms in victims exposed to sarin.

METHODS

Thirty-eight victims of the 1995 Tokyo subway sarin attack, all of whom had been treated in an emergency department for sarin intoxication, and 76 matched healthy control subjects underwent T1-weighted and diffusion tensor magnetic resonance imaging (DTI) in 2000 to 2001. Serum cholinesterase (ChE) levels measured immediately and longitudinally after the exposure and the current severity of chronic reports in the victims were also evaluated.

RESULTS

The voxel-based morphometry exhibited smaller than normal regional brain volumes in the insular cortex and neighboring white matter, as well as in the hippocampus in the victims. The reduced regional white matter volume correlated with decreased serum cholinesterase levels and with the severity of chronic somatic complaints related to interoceptive awareness. Voxel-based analysis of diffusion tensor magnetic resonance imaging further demonstrated an extensively lower than normal fractional anisotropy in the victims. All these findings were statistically significant (corrected p < 0.05).

INTERPRETATION

Sarin intoxication might be associated with structural changes in specific regions of the human brain, including those surrounding the insular cortex, which might be related to elevated subjective awareness of internal bodily status in exposed individuals.

Our recent experiences with sarin poisoning cases in Japan and pesticide users with references to some selected chemicals

Attention has been paid to neurobehavioral effects of occupational and environmental exposures to chemicals such as pesticides, heavy metals and organic solvents. The area of research that includes neurobehavioral methods and effects in occupational and environmental health has been called "Occupational and Environmental Neurology and Behavioral Medicine." The methods, by which early changes in neurological, cognitive and behavioral function can be assessed, include neurobehavioral test battery, neurophysiological methods, questionnaires and structured interview, biochemical markers and imaging techniques. The author presents his observations of neurobehavioral and neurophysiological effects in Tokyo subway sarin poisoning cases as well as in pesticide users (tobacco farmers) in Malaysia in relation to Green Tobacco Sickness (GTS). In sarin cases, a variety effects were observed 6-8 months after exposure, suggesting delayed neurological effects. Studies on pesticide users revealed that organophosphorus and dithiocarbamate affected peripheral nerve conduction and postural balance; subjective symptoms related to GTS were also observed, indicating the effects of nicotine absorbed from wet tobacco leaves. In addition, non-neurological effects of pesticides and other chemicals are presented, in relation to genetic polymorphism and oxidative stress.

Association between lower P300 amplitude and smaller anterior cingulate cortex volume in patients with posttraumatic stress disorder: a study of victims of Tokyo subway sarin attack

Previous investigations of auditory P300 event-related potentials have provided electrophysiological evidence for attentional problems in patients with posttraumatic stress disorder (PTSD). The present study sought to evaluate the relationship between P300 deficits and underlying brain morphological abnormalities in never-treated, comorbidity-free patients with PTSD following the Tokyo subway sarin attack. Out of 47 victims recruited, 8 victims with PTSD and 13 victims without PTSD were identified. Correlational analyses were performed between auditory P300 amplitude at Pz electrode site elicited in an oddball task and anterior cingulate gray matter volume that was shown to be reduced in our previous study using voxel-based morphometry on magnetic resonance imaging. Victims with PTSD showed significantly lower amplitudes of P300 compared with victims without PTSD, and the lower P300 amplitudes at Pz were significantly associated with higher avoidance/numbing scores in the PTSD group. Furthermore, in the PTSD group only, the P300 amplitudes showed a trend toward significant positive correlation with voxel densities of the anterior cingulate cortex gray matter. These results provide the first evidence that electrophysiological deficits of controlled attention observed in patients with PTSD may be linked to underlying brain morphological abnormalities.

Prevalence of post-traumatic stress disorder in incarcerated juvenile delinquents in Japan

The present study investigated frequency of post-traumatic stress disorder (PTSD) in incarcerated juvenile delinquents in Japan. The presence of overwhelming traumatic experiences, which fulfilled the DSM-IV criterion A for PTSD, was evaluated using a self-report questionnaire in 251 delinquents (206 males and 45 females). The structured interview using the Clinician-administered PTSD Scale for DSM-IV (CAPS) was administered to those with the experiences. A substantial portion (36%) of the delinquents reported experiences of exposure to such overwhelming traumatic events, which fulfilled the criterion A. Among those who met the criterion A, 48 subjects (40 males and eight females) received the CAPS interview. Ten (21%) out of 48 were diagnosed with current or past history of full PTSD. Three subjects out of the 10 were currently diagnosed with full PTSD. Another 10 subjects out of 48 (21%) had fulfilled the criteria for current or past history of partial PTSD. Among the 10, one was diagnosed as currently suffering from partial PTSD. In females, frequencies of the past history were quite high (50% for full PTSD and 25% for partial PTSD in the eight subjects), while none was currently diagnosed with PTSD.