Fentanyl is a potent, fast-acting synthetic opioid that has played a major role in the opioid overdose crisis in the United States for over five decades, with opioid-related deaths increasing sharply Show more
Fentanyl is a potent, fast-acting synthetic opioid that has played a major role in the opioid overdose crisis in the United States for over five decades, with opioid-related deaths increasing sharply in recent years. This study investigates the behavioral, histological, and molecular changes in the hippocampus of rats subjected to sub-acute fentanyl exposure. Two groups of rats were studied: one group received multiple fentanyl injections over approximately one week, while the control group received no fentanyl. A battery of behavioral tests related to memory and depression-including the Y-maze, shuttle box, tail suspension test, elevated plus maze, Barnes maze, Morris water maze, and forced swimming test-was administered. Electrophysiological assessments, including field potential recording and electromyography (EMG), were conducted to evaluate neural activity. Western blot analysis was performed to quantify the expression of brain-derived neurotrophic factor (BDNF) and RE1-silencing transcription factor (REST), while immunohistochemical analyses assessed hippocampal cellular alterations. Results showed that sub-acute fentanyl administration impaired behavioral performance in memory assessment tests (Y maze ( Show less
Given the heterogeneous nature of Alzheimer's disease (AD) and its higher prevalence in females, it is crucial to understand sex-related differences in AD presentation and changes in the brain. This s Show more
Given the heterogeneous nature of Alzheimer's disease (AD) and its higher prevalence in females, it is crucial to understand sex-related differences in AD presentation and changes in the brain. This systematic review investigates sex differences in AD and summarizes key findings from neuroimaging studies over the past two decades to examine how genetics, hormones, and lifestyle factors influence neuroimaging biomarkers and their correlation with cognitive decline and AD progression. A comprehensive literature search was conducted across several databases for human studies from 2004 to 2024 related to AD, biological sex differences, and neuroimaging. After a 3-step review process, the final extraction included 120 peer-reviewed studies using various neuroimaging modalities, such as MRI, amyloid-beta PET, tau-PET, and fluorodeoxyglucose (FDG) PET, to investigate sex as a biological predictor variable in adults with or at risk for AD. Over 90% of the reviewed studies identified clear sex-specific patterns of imaging biomarkers related to cognitive reserve, hormonal changes, APOE-ɛ4 genotype, inflammation, vascular health, and lifestyle factors. Machine learning studies increasingly incorporate sex as a key variable, revealing sex-specific biomarkers and improving model performance in predicting disease status and progression. Considering biological sex in AD research is essential for improving diagnostic accuracy, tailoring interventions, and health outcomes. This systematic review identifies sex-specific patterns in neuroimaging biomarkers of AD, influenced by cognitive reserve, hormones, APOE-ɛ4 genotype, inflammation, vascular health, and lifestyle. Recognizing these differences is crucial for understanding, diagnosis, and treatment efficacy. Show less