Od pobudzenia neuronów do zmiennych zapachów: Hipoteza mechanizmu powstawania zapachowych śladów przed napadem epilepsji
Full title: From neural excitability to volatile signatures: A mechanistic hypothesis for pre-ictal volatile organic compound signatures in epilepsy
W skrócie
Naukowcy badali, jak przed napadem epilepsji dochodzi do zmian chemicznych w organizmie, które można wyczuć jako zapachy. Odkryli, że podczas przygotowywania się do napadu neurony stają się bardziej pobudliwe, co powoduje stres oksydacyjny i produkcję specjalnych związków chemicznych, które mogą być wyczuwalne przez nos lub urządzenia. Badacze sugerują, że wykrywanie tych zapachów mogłoby w przyszłości pomóc w przewidywaniu napadów epilepsji, zanim się one faktycznie zdarzyć.
Oryginalny abstract (angielski)
OBJECTIVE: Seizure unpredictability remains a major contributor to morbidity in epilepsy, and biomarkers capable of identifying pre-ictal states are critically needed. Volatile organic compounds (VOCs) have emerged as potential noninvasive indicators of seizure susceptibility, yet the biological mechanisms linking pre-ictal neural states to peripheral volatile signatures remain poorly understood. METHODS: We conducted a narrative review in accordance with the Scale for the Assessment of Narrative Review Articles (SANRA) criteria integrating evidence from epilepsy neurobiology, oxidative stress, autonomic physiology, volatilomics, and seizure-detection science to develop a mechanistic hypothesis linking pre-ictal physiological processes to seizure-associated volatile signatures. RESULTS: Evidence supports several components of the proposed mechanistic hypothesis, although the strength and directness of evidence vary across pathway components. Pre-ictal states have been associated with increased neuronal excitability, altered neurophysiology, and heightened metabolic demand, creating conditions favorable for oxidative stress. Lipid peroxidation generates volatile and semi-volatile metabolites that can enter systemic circulation and become detectable peripherally. Autonomic modulation may further influence their expression and detectability. Human olfactory and analytical studies provide preliminary evidence for seizure-associated and pre-ictal volatile signatures. Although the complete pathway has not been experimentally validated, available evidence is consistent with a biologically plausible hypothesis linking central physiological processes to peripheral volatile signals. SIGNIFICANCE: This review proposes a multilevel mechanistic hypothesis for seizure-associated volatile signature generation. Volatile signatures are conceptualized as downstream reflections of physiological states associated with seizure susceptibility. This framework provides a foundation for future investigation of VOC-based seizure forecasting approaches in epilepsy.