👤 Allan Bayat

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

Alzheimer's disease (AD), a primary cause of dementia, involves cognitive decline and neuroinflammation. Human hair follicle stem cells (hHFSCs) have shown neuroprotective potential, but their effects on immune modulation, especially in xenogeneic transplantation, remain unclear. This study aimed to investigate the therapeutic potential of hHFSCs against memory impairment and neuroinflammation induced by streptozotocin (STZ) in male rats. Adult male Sprague-Dawley rats were intracerebroventricularly injected with STZ (3 mg/kg) to induce AD-like cognitive deficits. hHFSC transplantation (1 × 10 STZ significantly impaired memory in passive avoidance test, but not Y-maze. hHFSC significantly improved memory performance. mRNA analysis revealed elevated BDNF, TGFβ, and GFAP levels in the STZ group. The increased TGFβ and GFAP levels continued following hHFSC treatment, indicating a compensatory response. Moreover, pro-inflammatory factors (IL-1β, IL-6, and TNFα) were upregulated following hHFSC therapy, suggesting persistent neuroinflammation. hHFSC led to anti-inflammatory effects through the elevation of IL-10. In addition, hHFSCs significantly reduced hippocampal atrophy and neuronal loss induced by STZ. hHFSCs exhibit partial neuroprotective effects against STZ-induced memory impairment. The simultaneous upregulation of pro- and anti-inflammatory markers underscores the complexity of the inflammatory response in this xenogeneic model. Future investigations should consider immunocompromised models or immunosuppressive protocols better to isolate the therapeutic effects of hHFSCs from immune responses. Show less

The "NALCN channelosome" is an ion channel complex that consists of multiple proteins, including NALCN, UNC79, UNC80, and FAM155A. Only a small number of individuals with a neurodevelopmental syndrome have been reported with disease causing variants in NALCN and UNC80. However, no pathogenic UNC79 variants have been reported, and in vivo function of UNC79 in humans is largely unknown. We used international gene-matching efforts to identify patients harboring ultrarare heterozygous loss-of-function UNC79 variants and no other putative responsible genes. We used genetic manipulations in Drosophila and mice to test potential causal relationships between UNC79 variants and the pathology. We found 6 unrelated and affected patients with UNC79 variants. Five patients presented with overlapping neurodevelopmental features, including mild to moderate intellectual disability and a mild developmental delay, whereas a single patient reportedly had normal cognitive and motor development but was diagnosed with epilepsy and autistic features. All displayed behavioral issues and 4 patients had epilepsy. Drosophila with UNC79 knocked down displayed induced seizure-like phenotype. Mice with a heterozygous loss-of-function variant have a developmental delay in body weight compared with wild type. In addition, they have impaired ability in learning and memory. Our results demonstrate that heterozygous loss-of-function UNC79 variants are associated with neurologic pathologies. Show less