Olfactory dysfunction and its related molecular mechanisms in Parkinson's disease

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

Neurodegenerative diseases cause great medical and economic burdens for both patients and society; however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

Effect of Dl-3-n-Butylphthalide on olfaction in rotenone-induced Parkinson's rats

Background

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease. Olfactory dysfunction (OD) is an important nonmotor feature of PD. Dl-3-n-Butylphthalide (NBP) is a synthetic compound isolated from Apium graveolens seeds. The present study was conducted to investigate the effect of NBP on olfaction in rotenone-induced Parkinson's rats to explore the mechanism and pathway of OD in PD.

Methods

The PD model was established using rotenone-induced SD rats, divided into blank control, model, and treatment groups. A sham group was also established, with 10 rats in each group. The treatment group was given NBP (1 mg/kg, 10 mg/kg, and 100 mg/kg, dissolved in soybean oil) intragastrically for 28 days. Meanwhile, the control group rats were given intra-gastrically soybean oil. After behavioral testing, all rats were executed, and brain tissue was obtained. Proteomics and Proteomic quantification techniques (prm) quantification were used to detect proteomic changes in rat brain tissues.

Results

Compared with the control group, the model group showed significant differences in behavioral tests, and this difference was reduced after treatment. Proteomics results showed that after treatment with high-dose NBP, there were 42 differentially expressed proteins compared with the model group. Additionally, the olfactory marker (P08523) showed a significant upregulation difference. We then selected 22 target proteins for PRM quantification and quantified 17 of them. Among them, the olfactory marker protein was at least twofold upregulated in the RTH group compared to the model group.

Trends and hotspots in non-motor symptoms of Parkinson's disease: a 10-year bibliometric analysis

Non-motor symptoms are prevalent among individuals with Parkinson's disease (PD) and seriously affect patient quality of life, even more so than motor symptoms. In the past decade, an increasing number of studies have investigated non-motor symptoms in PD. The present study aimed to comprehensively analyze the global literature, trends, and hotspots of research investigating non-motor symptoms in PD through bibliometric methods. Studies addressing non-motor symptoms in the Web of Science Core Collection (WoSCC), published between January 2013 and December 2022, were retrieved. Bibliometric methods, including the R package "Bibliometrix," VOS viewer, and CiteSpace software, were used to investigate and visualize parameters, including yearly publications, country/region, institution, and authors, to collate and quantify information. Analysis of keywords and co-cited references explored trends and hotspots. There was a significant increase in the number of publications addressing the non-motor symptoms of PD, with a total of 3,521 articles retrieved. The United States was ranked first in terms of publications (n = 763) and citations (n = 11,269), maintaining its leadership position among all countries. King's College London (United Kingdom) was the most active institution among all publications (n = 133) and K Ray Chaudhuri was the author with the most publications (n = 131). Parkinsonism & Related Disorders published the most articles, while Movement Disorders was the most cited journal. Reference explosions have shown that early diagnosis, biomarkers, novel magnetic resonance imaging techniques, and deep brain stimulation have become research "hotspots" in recent years. Keyword clustering revealed that alpha-synuclein is the largest cluster for PD. The keyword heatmap revealed that non-motor symptoms appeared most frequently (n = 1,104), followed by quality of life (n = 502), dementia (n = 403), and depression (n = 397). Results of the present study provide an objective, comprehensive, and systematic analysis of these publications, and identifies trends and "hot" developments in this field of research. This work will inform investigators worldwide to help them conduct further research and develop new therapies.