Serum metabolomics analysis revealed metabolic disorders in Parkinson's disease

Neurotoxicity and aggressive behavior induced by anesthetic etomidate exposure in zebrafish: Insights from multi-omics and machine learning

Etomidate (ETO), widely employed as a surgical anesthetic and more recently recognized as a drug of abuse, has been frequently detected in aquatic environment. However, the toxicity assessment of ETO is insufficient. Adult zebrafish were used to investigate toxicological effects of ETO. Four weeks ETO exposure could induced abnormal behaviors, including reduced anxiety, memory impairment, and heightened aggression. The increased aggression was quantitatively characterized using machine learning, which revealed significantly elevated instantaneous velocity and drastic changes in angular velocity. ETO was predominantly accumulated in the zebrafish brain, where it binds to GABA-A receptors, leading to a significant increase in GABA content. Furthermore, fluorescent staining of reactive oxygen species (ROS) in the brain revealed that ETO exposure significantly increased the oxidative stress level. This oxidative stress resulted in mitochondrial swelling, rupture, and damage to myelinated nerve fibers, ultimately causing cerebral injury in zebrafish. Multi-omics analysis further elucidated that ETO exposure down-regulated the MAPK signaling pathway, hyperactivated motor proteins, and induced metabolic disorders of lipids and amino acids. In summary, this study demonstrates that ETO induces neurotoxicity and behavioral alterations in zebrafish. These findings provide a critical insight into the mechanisms underlying ETO's neurotoxic effects and contribute to a more comprehensive understanding of its environmental and health risks.

Metabolomic profiling reveals altered phenylalanine metabolism in Parkinson's disease in an Egyptian cohort

Introduction: Parkinson's disease (PD) is the most common motor neurodegenerative disease worldwide. Given the complexity of PD etiology and the different metabolic derangements correlated to the disease, metabolomics profiling of patients is a helpful tool to identify patho-mechanistic pathways for the disease development. Dopamine metabolism has been the target of several previous studies, of which some have reported lower phenylalanine and tyrosine levels in PD patients compared to controls. Methods: In this study, we have collected plasma from 27 PD patients, 18 reference controls, and 8 high-risk controls to perform a metabolomic study using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Results: Our findings revealed higher intensities of trans-cinnamate, a phenylalanine metabolite, in patients compared to reference controls. Thus, we hypothesize that phenylalanine metabolism has been shifted to produce trans-cinnamate via L-phenylalanine ammonia lyase (PAL), instead of producing tyrosine, a dopamine precursor, via phenylalanine hydroxylase (PAH). Discussion: Given that these metabolites are precursors to several other metabolic pathways, the intensities of many metabolites such as dopamine, norepinephrine, and 3-hydroxyanthranilic acid, which connects phenylalanine metabolism to that of tryptophan, have been altered. Consequently, and in respect to Metabolic Control Analysis (MCA) theory, the levels of tryptophan metabolites have also been altered. Some of these metabolites are tryptamine, melatonin, and nicotinamide. Thus, we assume that these alterations could contribute to the dopaminergic, adrenergic, and serotonergic neurodegeneration that happen in the disease.

Advancements in Genetic and Biochemical Insights: Unraveling the Etiopathogenesis of Neurodegeneration in Parkinson's Disease

Parkinson's disease (PD) is the second most prevalent neurodegenerative movement disorder worldwide, which is primarily characterized by motor impairments. Even though multiple hypotheses have been proposed over the decades that explain the pathogenesis of PD, presently, there are no cures or promising preventive therapies for PD. This could be attributed to the intricate pathophysiology of PD and the poorly understood molecular mechanism. To address these challenges comprehensively, a thorough disease model is imperative for a nuanced understanding of PD's underlying pathogenic mechanisms. This review offers a detailed analysis of the current state of knowledge regarding the molecular mechanisms underlying the pathogenesis of PD, with a particular emphasis on the roles played by gene-based factors in the disease's development and progression. This study includes an extensive discussion of the proteins and mutations of primary genes that are linked to PD, including α-synuclein, GBA1, LRRK2, VPS35, PINK1, DJ-1, and Parkin. Further, this review explores plausible mechanisms for DAergic neural loss, non-motor and non-dopaminergic pathologies, and the risk factors associated with PD. The present study will encourage the related research fields to understand better and analyze the current status of the biochemical mechanisms of PD, which might contribute to the design and development of efficacious and safe treatment strategies for PD in future endeavors.