ACUTE HIPPOCAMPAL SCLEROSIS FOLLOWING ECSTASY INGESTION

The Designer Drug 3-Fluoromethcathinone Induces Oxidative Stress and Activates Autophagy in HT22 Neuronal Cells

Synthetic cathinones are psychoactive substances, derivatives of a natural psychostimulant cathinone. Although many synthetic cathinones have lost their legal status in many countries, their abuse still continues worldwide. Recently, they have been reported to exert neurotoxic effects in vitro and in vivo. The molecular mechanisms of their action have not been fully elucidated. Recently, they have been linked to the induction of oxidative stress, autophagy, and apoptosis. The aim of this study was to investigate whether 3-fluoromethcathinone (3-FMC), a synthetic cathinone, is able to induce oxidative stress, autophagy, and apoptosis in HT22 immortalized mouse hippocampal cells. We found that treatment of HT22 cells with this compound results in a concentration-dependent increase in the intracellular production of reactive oxygen species. Moreover, 3-FMC induced concentration-dependent conversion of cytosolic LC3-I to membrane-bound LC3-II and formation of autophagic vacuoles. Additionally, the level of p62/SQSTM1 protein decreased after 3-FMC treatment, suggesting that accumulation of autophagic vacuoles resulted from activation rather than inhibition of autophagy. Our results also showed that 3-FMC at millimolar concentration is able to induce caspase-dependent apoptotic cell death in HT22 cells. Our findings suggest that abuse of 3-FMC may disturb neuronal homeostasis and impair functioning of the central nervous system.

Hippocampal volume reduction in female but not male recent abstinent methamphetamine users

Growing evidence suggests abnormalities in brain morphology including hippocampal structure in patients with methamphetamine (MA) dependence. This study was performed to examine hippocampal volume in abstinent MA users, and to further explore its relationship with cognitive function. 30 abstinent MA users (20 males and 10 females) with average 5.52 months of duration of abstinence and 29 healthy controls (19 males and 10 females) age 18-45 years old were recruited for clinical assessment and imaging scan. FreeSurfer was used to segment the hippocampus bilaterally, and hippocampal volumes were extracted for group and gender comparisons. Cognitive function was measured using the CogState Battery Chinese language version (CSB-C). Analysis of covariance (ANCOVA) controlling for education showed a significant group by gender interaction for the right hippocampal relative volume adjusted for total brain size (p = 0.020); there was a significant difference between male controls and female controls (p < 0.001), but such a difference did not exist between male patients and female patients (p = 0.203). No significant correlations were found between hippocampal volume and cognitive measures. There seems to be a gender difference in how MA affects hippocampal volume in abstinent MA users. Hippocampus might be an important treatment target for cognitive improvement and functional recovery in this patient population, especially in females.

Cognitive disorders after sporadic ecstasy use? A case report

Memory problems and changes in hippocampal structures after chronic ecstasy use are well described in the literature. Cognitive problems after incidental ecstasy use are rare, and the few patients described in case reports returned to their normal cognitive level after a relative short period. FV is a 39-year-old man who used an ecstasy tablet in 2005. This resulted in severe confusion for a few days. The confusion was followed by persistent memory complaints and difficulties orientating in new surroundings. An extensive neuropsychological examination 7 years after the ecstasy use revealed a severe memory disorder. Furthermore, his performance on a virtual reality test of navigation showed serious problems navigating in new surroundings. In comparison with matched control subjects (Bayesian approach for single case studies) his scores were significantly impaired on several subtasks of the navigation test. On a magnetic resonance imaging (MRI) scan of the brain bilateral hippocampal atrophy and sclerosis were visible, comparable to previous MRI studies describing hippocampal damage following ecstasy ingestion. This case report describes persistent memory and navigation disorders after sporadic ecstasy use, supported by structural brain abnormalities seen on the MRI scan. These findings revive the debate on whether sporadic ecstasy use can cause persistent cognitive deficits.

Hippocampal sclerosis in feline epilepsy

Hippocampal sclerosis (HS) refers to loss of hippocampal neurons and astrogliosis. In temporal lobe epilepsy (TLE), HS is a key factor for pharmacoresistance, even though the mechanisms are not quite understood. While experimental TLE models are available, there is lack of models reflecting the natural HS development. Among domestic animals, cats may present with TLE-like seizures in natural and experimental settings. With this study on the prevalence, segmental pattern and clinicopathological correlates of feline HS, we evaluated the translational value for human research. Evaluation schemes for human brains were applied to epileptic cats. The loss of neurons was morphometrically assessed and the degree of gliosis was recorded. Hippocampal changes resembling human HS were seen in about one third of epileptic cats. Most of these were associated with infiltrative diseases such as limbic encephalitis. Irrespective of the etiology and semiology of seizures, total hippocampal sclerosis was the most prevalent form seen in epileptic animals. Other HS types also occur at varying frequencies. Segmental differences to human HS can be explained by species-specific synaptic connectivities and a different spectrum of etiologies. All these variables require consideration when translating results from feline studies regarding seizure-associated changes of the temporal lobe and especially HS.

Alcohol and drugs in epilepsy: pathophysiology, presentation, possibilities, and prevention

The potentially serious outcomes from ingestion of and dependence on toxins make this an important topic for epileptologists. We must be aware of the potential for harm from compounds that may be freely available, yet patients may try to conceal their use. Problematic compounds may cause seizures either acutely or on withdrawal: Their use may reduce effectiveness of antiepileptic drugs, or may simply promote and enhance chaotic lifestyles. Any or all of these factors may worsen seizure control or even directly cause seizures. This article highlights the pathophysiology behind provoked seizures, provides clues to diagnosis, and then outlines the steps that clinicians should take to reduce the deleterious effects of toxic compounds.

Brain abnormalities detected on magnetic resonance imaging of amphetamine users presenting to an emergency department: a pilot study

OBJECTIVES

To determine the prevalence of occult brain abnormalities in magnetic resonance imaging of active amphetamine users.

DESIGN, SETTING AND PARTICIPANTS

Prospective convenience study in a tertiary hospital emergency department (ED). Patients presenting to the ED for an amphetamine-related reason were eligible for inclusion. We collected demographic data, drug use data, and performed a mini-mental state examination (MMSE).

MAIN OUTCOME MEASURES

The proportion of patients with an abnormality on their MRI scan.

RESULTS

Of 38 patients enrolled, 30 had MRI scans. Nineteen were male and their mean age was 26.7 +/- 5.4 years (range 19-41 years). The mean age of first amphetamine use was 18 years (range 13-26 years). Sixteen patients used crystal methamphetamine (mean amount 2.5 g/week), nine used amphetamine ("speed") (mean amount 2.9 g/week), and 23 used ecstasy (mean amount 2.3 tablets/week). Marijuana was smoked by 26 (mean amount 5.9 g/week), and 28 drank alcohol (mean amount 207 g/week). The median MMSE score was 27/30 (interquartile range, 26-29). Abnormalities on brain MRI scans were identified in six patients, most commonly an unidentified bright object (n = 4).

CONCLUSION

In this pilot study of brain MRI of young people attending the ED with an amphetamine-related presentation, one in five had an occult brain lesion. While the significance of this is uncertain, it is congruent with evidence that amphetamines cause brain injury.