Role and Dysregulation of miRNA in Patients with Parkinson's Disease

Current Strategies and Future Directions of Wearable Biosensors for Measuring Stress Biochemical Markers for Neuropsychiatric Applications

Most wearable biosensors aimed at capturing psychological state target stress biomarkers in the form of physical symptoms that can correlate with dysfunction in the central nervous system (CNS). However, such markers lack the specificity needed for diagnostic or preventative applications. Wearable biochemical sensors (WBSs) have the potential to fill this gap, however, the technology is still in its infancy. Most WBSs proposed thus far target cortisol. Although cortisol detection is demonstrated as a viable method for approximating the extent and severity of psychological stress, the hormone also lacks specificity. Multiplex WBSs that simultaneously target cortisol alongside other viable stress-related biochemical markers (SBMs) can prove to be indispensable for understanding how psychological stress contributes to the pathophysiology of neuropsychiatric illnesses (NPIs) and, thus, lead to the discovery of new biomarkers and more objective clinical tools. However, none target more than one SBM implicated in NPIs. Till this review, cortisol's connection to dysfunctions in the CNS, to other SBMs, and their implication in various NPIs has not been discussed in the context of developing WBS technology. As such, this review is meant to inform the biosensing and neuropsychiatric communities of viable future directions and possible challenges for WBS technology for neuropsychiatric applications.

Glutathione S-transferase: A keystone in Parkinson's disease pathogenesis and therapy

Parkinson's disease is a progressive neurodegenerative disorder that predominantly affects motor function due to the loss of dopaminergic neurons in the substantia nigra. It presents significant challenges, impacting millions worldwide with symptoms such as tremors, rigidity, bradykinesia, and postural instability, leading to decreased quality of life and increased morbidity. The pathogenesis of Parkinson's disease is multifaceted, involving complex interactions between genetic susceptibility, environmental factors, and aging, with oxidative stress playing a central role in neuronal degeneration. Glutathione S-Transferase enzymes are critical in the cellular defense mechanism against oxidative stress, catalysing the conjugation of the antioxidant glutathione to various toxic compounds, thereby facilitating their detoxification. Recent research underscores the importance of Glutathione S-Transferase in the pathophysiology of Parkinson's disease, revealing that genetic polymorphisms in Glutathione S-Transferase genes influence the risk and progression of the disease. These genetic variations can affect the enzymatic activity of Glutathione S-Transferase, thereby modulating an individual's capacity to detoxify reactive oxygen species and xenobiotics, which are implicated in Parkinson's disease neuropathological processes. Moreover, biochemical studies have elucidated the role of Glutathione S-Transferase in not only maintaining cellular redox balance but also in modulating various cellular signalling pathways, highlighting its neuroprotective potential. From a therapeutic perspective, targeting Glutathione S-Transferase pathways offers promising avenues for the development of novel treatments aimed at enhancing neuroprotection and mitigating disease progression. This review explores the evident and hypothesized roles of Glutathione S-Transferase in Parkinson's disease, providing a comprehensive overview of its importance and potential as a target for therapeutic intervention.

A review article on the development of dopaminergic neurons and establishment of dopaminergic neuron-based in vitro models by using immortal cell lines or stem cells to study and treat Parkinson's disease

The primary pathological hallmark of Parkinson's disease (PD) is the degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta, a critical midbrain region. In vitro models based on DA neurons provide a powerful platform for investigating the cellular and molecular mechanisms of PD and testing novel therapeutic strategies. A deep understanding of DA neuron development, including the signalling pathways and transcription factors involved, is essential for advancing PD research. This article first explores the differentiation and maturation processes of DA neurons in the midbrain, detailing the relevant signalling pathways. It then compares various in vitro models, including primary cells, immortalized cell lines, and stem cell-based models, focusing on the advantages and limitations of each. Special attention is given to the role of immortalized and stem cell models in PD research. This review aims to guide researchers in selecting the most appropriate model for their specific research goals. Ethical considerations and clinical implications of using stem cells in PD research are also discussed.

Plasma miRNAs across the Alzheimer's disease continuum: Relationship to central biomarkers

INTRODUCTION

MicroRNAs (miRNAs) play important roles in gene expression regulation and Alzheimer's disease (AD) pathogenesis.

METHODS

We investigated the association between baseline plasma miRNAs and central AD biomarkers from the Alzheimer's Disease Neuroimaging Initiative (ADNI; N = 803): amyloid, tau, and neurodegeneration (A/T/N). Differentially expressed miRNAs and their targets were identified, followed by pathway enrichment analysis. Machine learning approaches were applied to investigate the role of miRNAs as blood biomarkers.

RESULTS

We identified nine, two, and eight miRNAs significantly associated with A/T/N positivity, respectively. We identified 271 genes targeted by amyloid-related miRNAs with estrogen signaling receptor-mediated signaling among the enriched pathways. Additionally, 220 genes targeted by neurodegeneration-related miRNAs showed enrichment in pathways including the insulin growth factor 1 pathway. The classification performance of demographic information for A/T/N positivity was increased up to 9% with the inclusion of miRNAs.

DISCUSSION

Plasma miRNAs were associated with central A/T/N biomarkers, highlighting their potential as blood biomarkers.

HIGHLIGHTS

We performed association analysis of microRNAs (miRNAs) with amyloid/tau/neurodegeneration (A/T/N) biomarker positivity. We identified dysregulated miRNAs for A/T/N biomarker positivity. We identified Alzheimer's disease biomarker-specific/common pathways related to miRNAs. miRNAs improved the classification for A/T/N positivity by up to 9%. Our study highlights the potential of miRNAs as blood biomarkers.

Regulatory miR-SNP rs4636297A > G in miR-126 is linked to increased risk of rigidity feature in patients with Parkinson's disease

INTRODUCTION

A growing body of strong evidence shows that the dysfunction of miRNAs plays key roles in the development and progression of Parkinson's disease (PD), however, little data has been reported on the association of their SNPs with PD susceptibility. In this study, we investigated the association of regulatory miR-SNP rs4636297A > G with a functional effect on the expression of miRNA-126, as a key dysregulated miRNA in the PD, with the susceptibility and clinical features of the PD.

METHODS AND MATERIALS

In current study, we included a population consisting of 120 patients with PD and 120 clinically healthy individuals, and their blood samples were taken. After extracting the DNAs, the genotyping of the miR-SNP rs4636297A > G was done through RFLP-PCR technique. Finally, the association of this SNP with the risk and clinical features of PD was determined.

RESULTS

Although the results showed that the two groups did not differ significantly in terms of allelic and genotype frequencies, it was clinically found that individuals with genotypes carrying the minor allele G (AG and GG genotypes) of the miR-SNP rs4636297A > G had an increased risk of developing rigidity feature in the PD compared to its homozygous major AA genotype (GG genotype; OR = 5.14, p = 0.038 & GA genotype; OR = 4.32, p = 0.032).

CONCLUSION

We report for the first time a significant association of functional regulatory SNP rs4636297A > G in the miR-126 with the Parkinson's clinicopathology. Therefore, this miR-SNP can have a potential predictive biomarker capacity for rigidity in PD, although this hypothesis needs further investigation in the future.

Outcomes following spinal instrumented fusions in patients with parkinson's disease: a systematic review and meta-analysis

BACKGROUND

Parkinson's Disease (PD) patients represent challenging spinal surgery candidates due to associated frailty and deformity. This study consolidates the literature concerning spinal surgery outcomes in PD versus non-PD patients, to evaluate if PD predisposes patients to worse post-operative outcomes, so that treatment protocols can be optimised.

METHODS

A systematic review and meta-analysis was conducted of PubMed/Medline, Embase, and Google Scholar databases per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies of interest included comparative (PD versus non-PD) cohorts undergoing spinal instrumented fusions. Post-operative clinical outcomes were collated and compared for significance between cohorts. Further analysis was made on outcomes based on the different surgical procedures performed (Anterior Cervical Discectomy and Fusion (ACDF), Thoracolumbar or Lumbar fusions, Thoracolumbar or Lumbar fusions without Osteoporotic Vertebral Compression fracture (OVCF) patients). All statistical analysis was performed using The R Project for Statistical Computing (version 4.1.2), with a p-value of < 0.05 deemed statistically significant.

RESULTS

In total, 2,323,650 patients were included across 16 studies. Of those, 2,308,949 (99.37%) were patients without PD (non-PD), while 14,701 (0.63%) patients had PD at time of surgery. The collective mean age was 68.23 years (PD: 70.14 years vs non-PD: 64.86 years). Comparatively, there were 844,641 males (PD: 4,574; non-PD: 840,067) and 959,908 females (PD: 3,213; non-PD: 956,695). Overall, there were more post-operative complications in the PD cohort. Specifically, PD patients experienced significantly more surgical site infections (p = 0.01), increased rates of revision surgeries (p = 0.04) and increased venous thromboembolic events (p = 0.02) versus the non-PD cohort. In thoracolumbar/lumbar spinal fusions without OVCF patients, the PD cohort had increased rates of revision surgeries (p < 0.01) in comparison to the non-PD cohort. However, when including OVCF patients in thoracolumbar/lumbar spinal fusions, the PD cohort had significantly higher amounts of postoperative complications (p = 0.01), pneumonia (p = 0.02), and revision surgeries (p < 0.01) when compared to the non-PD cohort.

CONCLUSION

Although more robust prospective studies are needed, the results of this study highlight the need for advanced wound care management in the postoperative period, both in-hospital and in the community, in addition to comprehensive multidisciplinary care from allied health professionals, with potential for the use of Enhanced Recovery After Surgery (ERAS) protocols in PD patients undergoing spinal instrumented fusions.

CircHIVEP2 alleviates Parkinson's nerve damage and inflammatory response by targeting miR-485-3p

OBJECTIVE

Dysregulation of covalently closed circular RNAs (circRNAs) has been associated with neurological disorders, the role of circHIVP2 in Parkinson's disease (PD) and its molecular mechanism is not well understood.

METHODS

127 patients with PD and 85 healthy people were enrolled. RT-qPCR was employed to examine the levels of circHIVEP2. ROC curve to explore the diagnostic. Mpp+ induced the SH-SY5Y to construct an in vitro PD cell model. Cell viability, apoptosis, and secretion levels of inflammatory factors were analyzed by CCK-8, flow cytometry, and ELISA assay. CircHIVEP2 targets miRNA predicted by bioinformatics database and validated by the dual luciferase reporter and RIP assays.

RESULTS

CircHIVEP2 was typically lower in PD patients than in controls. CircHIVEP2 has certain specificity and sensitivity to recognize PD patients from healthy individuals. miR-485-3p, a target miRNA of circHIVEP2, was significantly elevated in PD patients. Additionally, MPP+ induction reduced cell viability and promoted apoptosis and inflammatory factor overproduction. However, overexpression of circHIVEP2 significantly inhibited the effects of MPP+, but this inhibition was significantly attenuated by elevated miR-485-3p.

CONCLUSION

circHIVEP2 is a potential diagnostic biomarker for PD, and its upregulation mitigated MPP+-induced nerve damage and inflammation and this may be through targeted by the miR-485-3p.

A Comprehensive Review of the Role of Biomarkers in Early Diagnosis of Parkinson's Disease

Parkinson's disease (PD) is a complex neurological, degenerative clinical condition depicted by the advancing loss of dopaminergic neurons in the substantia nigra pars compacta, which manifests itself as a myriad of sensorimotor and non-motor signs in patients. The disease occurs due to the reduced levels of the neurotransmitter dopamine in the brain, which is primarily associated with functional characteristics regarding mobility and cognition. The basal ganglion is mainly involved in the generation of cognitive functions and therefore is the most significantly associated area in PD. Since the classical diagnosis and assessment of PD depends majorly on the appearance of motor characteristics, which only arise when ~60-80% of the dopamine neuronal cell death has already occurred, it is imperative we focus on identifying biomarkers that can help us assess and diagnose PD in the earlier stages of disease progression, thus providing a better prognosis for the patients. This review article will focus on the different biomarkers that are currently available and in use, divided under the headings of clinical, biological, imaging, and genetic biomarkers, and assess their specificity and sensitivity toward providing an early assessment of Parkinson's for the patients and the future of preclinical diagnostics using molecular biomarkers. PD affects over 1% of the population worldwide and only ranks second to Alzheimer's disease in the context of its incidence and consequent socioeconomic burden. While recent breakthroughs in biomarkers have dramatically improved patients' odds of survival and prognosis, it still remains primarily a symptomatic diagnostic tool. It is an area of research that requires to focus on creating more advanced approaches toward diagnosing PD early, involving clinical diagnostics, neuroimaging technology, and molecular biology collaborations to provide the highest degree of care and quality of life that a Parkinson's patient deserves.

MiR-217 Regulates SIRT1 Expression and Promotes Inflammatory and Apoptotic Responses in Osteoarthritis

Previous studies have reported miR-217 uregulation in age-related pathologies. We investigated the impact of miR-217-5p on sirtuin 1 (SIRT1) regulation in human osteoarthritic (OA) chondrocytes. MiR-217 target enrichment analyses were performed using three public databases, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. MiR-217-5p expression levels were quantified in normal and OA chondrocytes. SIRT1 expression levels, nuclear factor kappa-B p65 subunit (NF-κBp65) and p53 acetylation levels, and expression levels of OA-related pro-inflammatory markers [tumor necrosis factor α (TNFα), interleukin 1β (IL-1β), IL-6], pro-apoptotic markers [Bax, pro-caspase 3, cleaved caspase 3] and matrix regulators [matrix metalloproteinase (MMP)-1, MMP-13, MMP-9, Collagen 2 (COL2A1), Aggrecan (ACAN)] were evaluated in miR-217 mimic-treated and/or miR-217 inhibitor-treated OA chondrocytes, with/without subsequent treatment with siRNA against SIRT1 (siSIRT1). MiR-217-5p was upregulated in OA chondrocytes, while target prediction/enrichment analyses revealed SIRT1 as miR-217 target-gene. Deacetylation of NF-κBp65 and p53 in miR-217 inhibitor-treated OA chondrocytes was reversed by siSIRT1 treatment. MiR-217 inhibitor-treated OA chondrocytes showed increased COL2A1, ACAN and decreased IL-1β, IL-6, TNFα, Bax, cleaved caspase 3 and MMPs expression levels, which were reversed following miR-217 inhibitor/siSIRT1 treatment. Our findings highlight the impact of miR-217-5p on SIRT1 downregulation contributing to OA pathogenesis.

Mechanism and Therapeutic Prospect of miRNAs in Neurodegenerative Diseases

MicroRNAs (miRNAs) are the smallest class of noncoding RNAs, which widely exist in animals and plants. They can inhibit translation or overexpression by combining with mRNA and participate in posttranscriptional regulation of genes, resulting in reduced expression of target proteins, affecting the development, growth, aging, metabolism, and other physiological and pathological processes of animals and plants. It is a powerful negative regulator of gene expression. It mediates the information exchange between different cellular pathways in cellular homeostasis and stress response and regulates the differentiation, plasticity, and neurotransmission of neurons. In neurodegenerative diseases, in addition to the complex interactions between genetic susceptibility and environmental factors, miRNAs can serve as a promising diagnostic tool for diseases. They can also increase or reduce neuronal damage by regulating the body's signaling pathways, immune system, stem cells, gut microbiota, etc. They can not only affect the occurrence of diseases and exacerbate disease progression but also promote neuronal repair and reduce apoptosis, to prevent and slow down the development of diseases. This article reviews the research progress of miRNAs on the mechanism and treatment of neurodegenerative diseases in the nervous system. This trial is registered with NCT01819545, NCT02129452, NCT04120493, NCT04840823, NCT02253732, NCT02045056, NCT03388242, NCT01992029, NCT04961450, NCT03088839, NCT04137926, NCT02283073, NCT04509271, NCT02859428, and NCT05243017.

A Next-Generation Sequencing Study in a Cohort of Sicilian Patients with Parkinson's Disease

Parkinson's disease (PD) is a multisystem and multifactorial disorder and, therefore, the application of modern genetic techniques may assist in unraveling its complex pathophysiology. We conducted a clinical-demographic evaluation of 126 patients with PD, all of whom were Caucasian and of Sicilian ancestry. DNA was extracted from the peripheral blood for each patient, followed by sequencing using a Next-Generation Sequencing system. This system was based on a custom gene panel comprising 162 genes. The sample underwent further filtering, taking into account the allele frequencies of genetic variants, their presence in the Human Gene Mutation Database, and their association in the literature with PD or other movement/neurodegenerative disorders. The largest number of variants was identified in the leucine-rich repeat kinase 2 (LRRK2) gene. However, variants in other genes, such as acid beta-glucosidase (GBA), DNA polymerase gamma catalytic subunit (POLG), and parkin RBR E3 ubiquitin protein ligase (PRKN), were also discovered. Interestingly, some of these variants had not been previously associated with PD. Enhancing our understanding of the genetic basis of PD and identifying new variants possibly linked to the disease will contribute to improved diagnostic accuracy, therapeutic developments, and prognostic insights for affected individuals.

NGS study in a sicilian case series with a genetic diagnosis for Gerstmann-Sträussler-Scheinker syndrome (PRNP, p.P102L)

BACKGROUND

Gerstmann Sträussler Scheinker (GSS) is an inherited, invariably fatal prion disease. Like other human prion diseases, GSS is caused by missense mutations in the prion protein (PrP) gene (PRNP), and by the formation and overtime accumulation of the misfolded, pathogenic scrapie PrP (PrPSc). The first mutation identified in the PRNP gene, and the one blamed as the main cause of the disease, is c.C305T:p.P102L.

METHODS AND RESULTS

The Sanger sequencing method was performed on the PRNP gene for the detection of c.C305T:p.P102L mutations in a cohort of 10 subjects; moreover, a study was carried out, using Next Generation Sequencing (NGS), by sequencing a group of genes related to amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), movement disorders and dementia which show a phenotypic profile similar to that of GSS. The results obtained from the study using NGS indicate the potential role of other genetic variants which could contribute to the various GSS phenotypes.

CONCLUSIONS

In conclusion, we highlight the large clinical variability in subjects presenting with GSS and p.P102L, as well as the hypothesis that the mutation in PrP codon 102 alone is not sufficient to trigger the cardinal clinical signs of the disease; furthermore, we do not exclude the possibility that further genetic variants play a decisive role in the aspects of the various phenotypes with which GSS manifests itself.

MEIS1 Is a Common Transcription Repressor of the miR-23a and NORHA Axis in Granulosa Cells

MicroRNA-23a (miR-23a) is an endogenous small activating RNA (saRNA) involved in ovarian granulosa cell (GC) apoptosis and sow fertility by activating lncRNA NORHA transcription. Here, we reported that both miR-23a and NORHA were repressed by a common transcription factor MEIS1, which forms a small network regulating sow GC apoptosis. We characterized the pig miR-23a core promoter, and the putative binding sites of 26 common transcription factors were detected in the core promoters of both miR-23a and NORHA. Of them, transcription factor MEIS1 expression was the highest in the ovary, and widely distributed in various ovarian cells, including GCs. Functionally, MEIS1 is involved in follicular atresia by inhibiting GC apoptosis. Luciferase reporter and ChIP assays showed that transcription factor MEIS1 represses the transcription activity of miR-23a and NORHA through direct binding to their core promoters. Furthermore, MEIS1 represses miR-23a and NORHA expression in GCs. Additionally, MEIS1 inhibits the expression of FoxO1, a downstream of the miR-23a/NORHA axis, and GC apoptosis by repressing the miR-23a/NORHA axis. Overall, our findings point to MEIS1 as a common transcription repressor of miR-23a and NORHA, and develop the miR-23a/NORHA axis into a small regulatory network regulating GC apoptosis and female fertility.