Exposure to low (10 cGy) doses of 4He ions leads to an apparent increase in risk taking propensity in female rats.

The planned missions to the Moon and Mars will present more significant health challenges to astronauts compared to low earth orbit missions. During deep space missions, astronauts will be constantly exposed to Space radiation (SR). Multiple rodent studies suggest that < 25 cGy of SR impairs performance in executive functions, which play a key role in advanced cognitive processes, but also regulate response inhibition and impulse control. There is the possibility that SR exposure may exacerbate aberrant behaviors evoked by psychological stress related to exposure to isolated and confined (ICE) hostile environment or independently induce additional aberrant behaviors. This study has determined that female Wistar rats exposed to 10 cGy of 250 MeV/n He had an increased risk taking propensity (RTP)\compared to shams. The increased RTP of the He-exposed rats was associated with significantly increased reaction times during the trials, suggesting a SR-induced loss of processing speed. The response times of the He-exposed rats were even further reduced in trials that immediately followed a loss, raising the possibility that conflict and interference avoidance may be impaired after SR exposure. Whether these findings occur following other types of SR exposure, and/or in male rats remains to be determined.

Scoping review of disease-modifying effect of drugs in experimental epilepsy.

Objective: Epilepsy affects ~50 million people worldwide causing significant medical, financial, and sociologic concerns for affected patients and their families. To date, treatment of epilepsy is primarily symptomatic management because few effective preventative or disease-modifying interventions exist. However, recent research has identified neurobiological mechanisms of epileptogenesis, providing new pharmacologic targets to investigate. The current scientific evidence remains scattered across multiple studies using different model and experimental designs. The review compiles different models of anti-epileptogenic investigation and highlights specific compounds with potential epileptogenesis-modifying experimental drugs. It provides a platform for standardization of future epilepsy research to allow a more robust compound analysis of compounds with potential for epilepsy prevention. Methods: PubMed, Ovid MEDLINE, and Web of Science were searched from 2007 to 2021. Studies with murine models of epileptogenesis and explicitly detailed experimental procedures were included in the scoping review. In total, 51 articles were selected from 14,983 and then grouped by five core variables: (1) seizure frequency, (2) seizure severity, (3) spontaneous recurrent seizures (SRS), (4) seizure duration, and (5) mossy fiber sprouting (MFS). The variables were differentiated based on experimental models including methods of seizure induction, treatment schedule and timeline of data collection. Data was categorized by the five core variables and analyzed by converting original treatment values to units of percent of its respective control. Results: Discrepancies in current epileptogenesis models significantly complicate inter-study comparison of potential anti-epileptogenic interventions. With our analysis, many compounds showed a potential to reduce epileptogenic characteristics defined by the five core variables. WIN55,212-2, aspirin, rapamycin, 1400W, and LEV + BQ788 were identified compounds with the potential of effective anti-epileptic properties. Significance: Our review highlights the need for consistent methodology in epilepsy research and provides a novel approach for future research. Inconsistent experimental designs hinder study comparison, slowing the progression of treatments for epilepsy. If the research community can optimize and standardize parameters such as methods of seizure induction, administration schedule, sampling time, and aniMal models, more robust meta-analysis and collaborative research would follow. Additionally, some compounds such as rapamycin, WIN 55,212-2, aspirin, 1400W, and LEV + BQ788 showed anti-epileptogenic modulation across multiple variables. We believe they warrant further study both individually and synergistically.