A systematic review of salivary biomarkers in Parkinson's disease

Potential biofluid markers for cognitive impairment in Parkinson's disease

Cognitive impairment is a particularly severe non-motor symptom of Parkinson's disease that significantly diminishes the quality of life of affected individuals. Identifying reliable biomarkers for cognitive impairment in Parkinson's disease is essential for early diagnosis, prognostic assessments, and the development of targeted therapies. This review aims to summarize recent advancements in biofluid biomarkers for cognitive impairment in Parkinson's disease, focusing on the detection of specific proteins, metabolites, and other biomarkers in blood, cerebrospinal fluid, and saliva. These biomarkers can shed light on the multifaceted etiology of cognitive impairment in Parkinson's disease, which includes protein misfolding, neurodegeneration, inflammation, and oxidative stress. The integration of biofluid biomarkers with neuroimaging and clinical data can facilitate the development of predictive models to enhance early diagnosis and monitor the progression of cognitive impairment in patients with Parkinson's disease. This comprehensive approach can improve the existing understanding of the mechanisms driving cognitive decline and support the development of targeted therapeutic strategies aimed at modifying the course of cognitive impairment in Parkinson's disease. Despite the promise of these biomarkers in characterizing the mechanisms underlying cognitive decline in Parkinson's disease, further research is necessary to validate their clinical utility and establish a standardized framework for early detection and monitoring of cognitive impairment in Parkinson's disease.

The inflammatory markers MHR and NLR are independent risk factors for adverse events during hospitalization in older adult patients with myocardial injury caused by acute carbon monoxide poisoning: a retrospective cross-sectional study

Acute carbon monoxide poisoning-induced myocardial injury is easily overlooked. However, patients with acute carbon monoxide poisoning, especially older adult patients, often have difficulty expressing clinical symptoms due to early consciousness disturbances, making the early identification of complications challenging and leading to delayed diagnosis and treatment. Therefore, exploring indicators that can predict in-hospital cardiovascular adverse events in older adult patients with acute carbon monoxide poisoning -induced myocardial injury has important clinical significance. Therefore, this retrospective cross-sectional study included older adult patients with acute carbon monoxide poisoning-induced myocardial injury at the Department of Hyperbaric Oxygen of Beijing Chao-Yang Hospital from January 2013 to December 2019. A total of 119 older adult patients with acute carbon monoxide poisoning-induced myocardial injury were included in the study, with 94 patients in the nonevent group (54 males, 40 females, 71.09 ± 7.60 years) and 25 patients in the cardiovascular adverse event group (10 males, 15 females, 71.48 ± 10.38 years). Compared with those in the nonevent group, creatine kinase isoenzyme levels, triglyceride levels, the neutrophil/lymphocyte ratio and the monocyte/high-density lipoprotein cholesterol ratio were significantly greater in the cardiovascular adverse event group, and high-density lipoprotein cholesterol levels were significantly lower in the cardiovascular adverse event group. Further binary logistic regression analysis showed that higher monocyte/high-density lipoprotein cholesterol ratio might be an independent risk factor for in-hospital adverse events in older adult patients with acute carbon monoxide poisoning-induced myocardial injury (OR = 109.783, 95% CI: 2.644-4557.834; P = 0.013). The area under the curve of the monocyte/high-density lipoprotein cholesterol ratio in predicting in-hospital cardiovascular adverse events in older adult patients with myocardial injury due to acute carbon monoxide poisoning was 0.797, the cutoff value was 0.645, the sensitivity was 68.0%, and the specificity was 88.2%. The inflammatory indicators monocyte/high-density lipoprotein cholesterol ratio and neutrophil/lymphocyte ratio were identified as an independent risk factor for predicting in-hospital cardiovascular adverse events in older adult patients with acute carbon monoxide poisoning-induced myocardial injury in this study. Specifically, monocyte/high-density lipoprotein cholesterol ratio was identified as an independent risk factor for predicting adverse events during hospitalization.

The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

JOURNAL/nrgr/04.03/01300535-202508000-00026/figure1/v/2024-09-30T120553Z/r/image-tiff Interferon regulatory factor 7 plays a crucial role in the innate immune response. However, whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains unknown. Here we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial cells. Both the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 phenotype. In addition, siRNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase, tumor necrosis factor α, CD16, CD32, and CD86 and increased the expression of the anti-inflammatory markers ARG1 and YM1. Taken together, our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.

Insights into spinal muscular atrophy from molecular biomarkers

Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle weakness. It is one of the most common genetic causes of mortality among infants aged less than 2 years. Biomarker research is currently receiving more attention, and new candidate biomarkers are constantly being discovered. This review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and cons. We also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy, which are classified as either specific or non-specific biomarkers. This review provides new insights into the pathogenesis of spinal muscular atrophy, the mechanism of biomarkers in response to drug-modified therapies, the selection of biomarker candidates, and would promote the development of future research. Furthermore, the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.

Peripheral transcutaneous electrical stimulation to improve cognition: a review of the main effects in healthy humans and in mildly cognitively impaired patient populations

Peripheral nerve stimulation (PNS) is an ancient technique, up to now mainly used for pain management. The least invasive approach for PNS is transcutaneous electrical stimulation (TENS), which is performed by delivering mild electric currents through the skin and, depending on the stimulation pattern, activates the somatosensory Aβ-, Aδ- and C-fibers. In addition to its use for pain relief, accumulating data indicates that TENS can have broad-spectrum cognitive effects through the activation of neuromodulatory brain pathways. This review aims to summarize the current evidence on the cognitive effects of TENS, from healthy participants and mildly cognitively affected patients. Most studies on this topic have investigated the effects of TENS on memory, while fewer studies have explored attention, executive functions, and verbal fluency. Overall, promising evidence suggests that TENS may exert positive effects on specific cognitive functions. Further research is needed to build consensus on the most effective stimulation protocols, for both neurorehabilitation and enhancement, and to better understand the neurobiological mechanisms underlying the cognitive effects of TENS.

Metabolomics in Parkinson's Disease and Correlation with Disease State

Changes in the level of metabolites, small molecules that are intermediates produced by metabolism or catabolism, are associated with developing diseases. Metabolite signatures in body fluids such as plasma, cerebrospinal fluid, urine, and saliva are associated with Parkinson's disease. Here, we discuss alteration of metabolites in the TCA cycle, pentose phosphate pathway, kynurenic network, and redox system. We also summarize the efforts of many research groups to differentiate between metabolite profiles that characterize PD motor progression and dyskinesia, gait and balance, and non-motor symptoms such as depression and cognitive decline. Understanding how changes in metabolites lead to progression in PD may allow for the identification of individuals at the earliest stage of the disease and the development of new therapeutic strategies.

Proteopathic seed amplification assays in easily accessible specimens for human synucleinopathies, tauopathies, and prionopathies: A scoping review

A hallmark event in neurodegenerative diseases is represented by the misfolding, aggregation and accumulation of proteins, leading to cellular and network dysfunction preceding the development of clinical symptoms by years. Early diagnosis represents a crucial issue in the field of neuroscience as it offers the potential to utilize this therapeutic window in the future to manage disease-modifying therapy. Seed amplification assays, including Real-Time Quaking-Induced Conversion (RT-QuIC) and Protein Misfolding Cyclic Amplification (PMCA), have emerged in recent years as innovative techniques developed to detect minute amounts of amyloidogenic proteins. These techniques can utilize various biological fluids and tissues, with most evidence to date regarding their potential diagnostic use focusing on cerebrospinal fluid. In this scoping review, we aimed to investigate and discuss the available evidence regarding the diagnostic use of these assays on easily accessible biological fluids and tissues in patients affected by synucleinopathies, tauopathies or prion diseases. From a systematic search on two databases, Scopus and Pubmed, we identified 49 studies. Although most identified studies have used skin and olfactory mucosa as biological samples, there is preliminary evidence suggesting the potential implementation of these techniques using fluids as blood, saliva and tears. The results achieved so far, as well as methodological aspects and limitations to overcome, are discussed.