Sporadic Onset Research Articles

MicroRNA-5572 Is Associated with Endoplasmic Reticulum Stress Responses in Low Zinc Treated and SOD1 G85R-Transfected HEK293 Cells.

Amyotrophic lateral sclerosis (ALS) is a fetal neurodegenerative disease. The mechanism of sporadic ALS onset remains unclarified in detail. Disruption of zinc homeostasis could be related to sporadic ALS. Previously, we first reported miR-5572 as a microRNA (miRNA) among those identified in the spinal cords of patients with sporadic ALS. However, since its function in ALS remained unknown, this study further examined the role of miR-5572 in low-zinc status and ALS model cells which transfected with causative gene, Cu/Zn superoxide dismutase 1 (SOD1) G85R mutant vector. The miR-5572 level was increased by low-zinc condition accompanied by increase of endoplasmic reticulum (ER) stress. In addition, increase of miR-5572 enhanced the cellular toxicity induced by low-zinc treatment. The expression of miR-5572 was also increased, which was accompanied by an increase of ER stress markers associated with SOD1 aggregation formation. Cell death and ER stress makers levels induced by tunicamycin treatment were further increased in miR-5572 mimic-transfected cells. This study showed that miR-5572 exacerbated ER stress toxicity associated with low-zinc status and mutant SOD1 aggregates in ALS.

Occupational exposure protection and perioperative management of sudden infectious diseases from the perspective of COVID-19.

The coronavirus disease (COVID-19) SARS-CoV-2 virus epidemic continues to exhibit a sporadic onset trend due to the continuous variation of the novel coronavirus. However, the psychological impact of the pandemic persists. It is crucial to reflect on our experiences to better prepare for future large-scale infectious diseases. During outbreaks of infectious diseases, patients may still require orthopaedic surgery. It is crucial to prioritize the safety of medical staff and establish procedures to ensure their protection. However, with the implementation of a series of standardized operational protection procedures, orthopaedic surgeons can safely perform their duties without the risk of contracting COVID-19. There is no doubt that the orthopaedic occupational exposure protection process and perioperative management plan for global infectious diseases, such as COVID-19, require a standardized summarization process and a narrative review.

Transcranial Sonography Characteristics of Cerebellar Neurodegenerative Ataxias.

Cerebellar neurodegenerative ataxias are a group of disorders affecting the cerebellum and its pathways with different neurological structures. Transcranial sonography (TCS) has been used for the evaluation of brain parenchymal structures in various diseases because of its fast and safe utilization, especially in neuropsychiatric and neurodegenerative diseases. The aim of our study was to investigate TCS characteristics of patients with neurodegenerative cerebellar ataxias. In our study, we included 74 patients with cerebellar degenerative ataxia; 36.5% had autosomal dominant onset, while 33.8% had sporadic onset. Standardized ultrasonographic planes were used for the identification of brain structures of interest. The SARA, INAS, neuropsychological and psychiatric scales were used for the further clinical evaluation of our study participants. The brainstem raphe was discontinued in 33.8% of the patients. The substantia nigra (SN) hyperechogenicity was identified in 79.7%. The third and fourth ventricle enlargement had 79.7% and 45.9% of patients, respectively. A positive and statistically significant correlation was found between SN hyperechogenicity with dystonia (p < 0.01), rigidity and dyskinesia (p < 0.05). The higher SARA total score is statistically significantly correlated with the larger diameter of the III (r = 0.373; p = 0.001) and IV ventricles (r = 0.324; p = 0.005). In such patients, the echogenicity of substantia nigra has been linked to extrapyramidal signs, and raphe discontinuity to depression. Furthermore, ataxia and its clinical subtypes have positively correlated with the IV ventricle diameter, indicating brain atrophy and brain mass reduction.

Genetic and in silico analysis of Indian sporadic young onset patient with amyotrophic lateral sclerosis

Background Amyotrophic lateral sclerosis (ALS) is an old onset devastating neurodegenerative disorder. Young-onset ALS cases especially sporadic ones who are between 25 and 45 years are rarely affected by the disease. Despite the identification of numerous candidate genes associated with ALS, the etiology of the disease remains elusive due to extreme genetic and phenotypic variability. The advent of affordable whole exome sequencing (WES) has opened new avenues for unraveling the disease’s pathophysiology better. Methods and results We aimed to determine the genetic basis of an Indian-origin, young onset sporadic ALS patient with very rapid deterioration of the disease course without any cognitive decline who was screened for mutations in major ALS candidate genes by WES. Variants detected were reconfirmed by Sanger sequencing. The clinicopathological features were investigated and two heterozygous missense variants were identified: R452W, not previously associated with ALS, present in one of the four conserved C terminal domains in ANXA11 and R208W in SIGMAR1, respectively. Both of these variants were predicted to be damaging by pathogenicity prediction tools and various in silico methods. Conclusion Our study revealed two potentially pathogenic variants in two ALS candidate genes. The genetic makeup of ALS patients from India has been the subject of a few prior studies, but none of them examined ANXA11 and SIGMAR1 genes so far. These results establish the framework for additional research into the pathogenic processes behind these variations that result in sporadic ALS disease and further our understanding of the genetic makeup of Indian ALS patients.

Sodium hypochlorite inactivation of human CJD prions.

Prion diseases are transmissible, fatal neurologic diseases of mammals caused by the accumulation of mis-folded, disease associated prion protein (PrPd). Creutzfeldt-Jakob Disease (CJD) is the most common human prion disease and can occur by sporadic onset (sCJD) (~85% of CJD cases), genetic mutations in the prion protein gene (10-15%) or iatrogenic transmission (rare). PrPd is difficult to inactivate and many methods to reduce prion infectivity are dangerous, caustic, expensive, or impractical. Identifying viable and safe methods for decontamination of CJD exposed materials is critically important for medical facilities and research institutions. Previous research has shown that concentrated sodium hypochlorite (bleach) was effective at inactivation of CJD prions derived from brains of mice or guinea pigs. Unfortunately, human prions adapted to rodents may mis-fold differently than in humans, and the rodent adapted prions may not have the same resistance or susceptibility to inactivation present in bona fide CJD prions. To confirm that bleach was efficacious against human sourced CJD prions, we exposed different subtypes of sCJD-infected human brain homogenates to different concentrations of bleach for increasing exposure times. Initial and residual prion seeding activity following inactivation were measured using Real-Time Quaking Induced Conversion. In addition, we tested how passage of human sCJD into either transgenic mice that expressed human prion protein, or transmission of CJD to human cerebral organoids (CO), two common laboratory practices, may affect CJD prions' susceptibility to bleach inactivation. Our results show that bleach is effective against human sourced sCJD prions, and both treatment time and concentration of bleach were important factors for CJD inactivation. CJD derived from human brains, transgenic mouse brains or CO were all susceptible to inactivation with as low as a 10 percent bleach solution with a 30-minute exposure time or a 50 percent bleach solution with as little as a 1-minute exposure time.

Lnc-HIBADH-4 Regulates Autophagy-Lysosome Pathway in Amyotrophic Lateral Sclerosis by Targeting Cathepsin D

Amyotrophic lateral sclerosis (ALS) is the most prevalent and lethal class of severe motor neuron diseases (MND) with no efficacious treatment. The pathogenic mechanisms underlying ALS remain unclear. Nearly 90% of patients exhibit sporadic onset (sALS). Therefore, elucidating the pathophysiology of ALS is imperative. Long non-coding RNA (lncRNA) is a large class of non-coding RNAs that regulate transcription, translation, and post-translational processes. LncRNAs contribute to the pathogenesis of diverse neurodegenerative disorders and hold promise as targets for interference in the realm of neurodegeneration. However, the mechanisms of which lncRNAs are involved in ALS have not been thoroughly investigated. We identified and validated a downregulated lncRNA, lnc-HIBADH-4, in ALS which correlated with disease severity and overall survival. Lnc-HIBADH-4 acted as a “molecular sponge” regulating lysosomal function through the lnc-HIBADH-4/miR-326/CTSD pathway, thereby impacting autophagy-lysosome dynamics and the levels of cell proliferation and apoptosis. Therefore, this study discovered and revealed the role of lnc-HIBADH-4 in the pathogenesis of ALS. With further research, lnc-HIBADH-4 is expected to provide a new biomarker in the diagnosis and treatment of ALS.

Mild cognitive impairment in novel SPG4/SPAST mutation‐related sporadic late onset hereditary spastic paraplegia: case series

AbstractBackgroundMutations and deletions in the SPG4/SPAST gene cause for up to 50% of the autosomal dominant forms of hereditary spastic paraplegia (HSP) and for up to 15% of the sporadic cases. Affected individuals have pyramidal signs in the lower limbs and some present additional features. Cognitive impairment is common in late‐onset forms of HSPs.MethodsThis study examined the cognitive abilities of 20 sporadic late‐onset patients with HSP using next‐generation sequencing. We also used a combination of the Mini‐Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) to assess their cognition.ResultsThe present study led to the discovery of three new pathogenic mutations of the SPG4 gene through evolutionary conservation and analysis of structural models. We also confirmed mild cognitive impairment (MCI) with normal MMSE scores (≥27) and reduced MoCA scores (&lt;26) in these HSP‐SPG4 mutant patients. Such individuals mainly present with impaired executive function, delayed memory, abstraction and language.ConclusionsThe results broaden the mutational space of SPG4‐associated HSP with sporadic late‐onset modality and indicate a combination of reduced MoCA and normal MMSE for diagnosis, indicating that clinicians should consider performing a MoCA to detect MCI in patients with HSP, particularly those with sporadic onset SPG4/SPAST‐HSP.

Dermoscopic Features of Blue Rubber Bleb Nevus Syndrome

Abstract Blue rubber bleb nevus syndrome (BRBNS) usually has a sporadic onset. It is characterized as blue to purple, soft, rubbery, compressible nodules over any region in the skin or mucous membrane. It may be complicated by acute hemorrhage, iron deficiency anemia, bowel infarction, skeletal bowing, pathologic fracture, etc., Here, we present the case of a 9-year-old boy who presented with a complaint of multiple reddish to bluish nontender nodules over the tongue, chest, neck, abdomen, back, B/L upper limb, scrotum, and B/L lower limb including sole. Dermoscopic examination demonstrated red–purple globules with verrucous surface with lacunae separated by a white linear structure corresponding to fibrous demarcations. With the help of dermoscopic and clinical examination, the patient was diagnosed as having BRBNS.

Verification of propagation hypothesis in patients with sporadic hand onset amyotrophic lateral sclerosis.

If lesions in sporadic amyotrophic lateral sclerosis (ALS) originate from a single focal onset site and spread contiguously by prion-like cell-to-cell propagation at a constant speed, the lesion spread time should be proportional to the anatomical distance. We verify this model in the patients. In 29 sporadic ALS patients with hand onset followed by spread to shoulder and leg, we retrospectively evaluated the inter/intra-regional spread time ratio: time interval of symptoms from hand-to-leg divided by that from hand-to-shoulder. We also obtained the corresponding inter-/intra-regional distance ratios of spinal cord from magnetic resonance imaging of 12 patients, and those of primary motor cortex from coordinates using neuroimaging software. Inter-/intra-regional spread time ratios ranged from 0.29 to 6.00 (median 1.20). Distance ratios ranged from 1.85 to 2.86 in primary motor cortex and from 5.79 to 8.67 in spinal cord. Taken together with clinical manifestations, of 27 patients with the requisite information available, lesion spreading was consistent with the model in primary motor cortex in 4 (14.8%) patients, and in spinal cord in only 1 (3.7%) patient. However, in more patients (12 of 29 patients: 41.4%), the inter-regional spread times in a long anatomical distance of hand-to-leg were shorter than or equal to the intra-regional spread times in a short anatomical distance of hand-to-shoulder. Contiguous cell-to-cell propagation at a constant speed might not play a major role at least in distant lesion spreading of ALS. Several mechanisms can be responsible for progression in ALS.

Molecular landscape and survival outcomes on early phase clinical trials in sporadic young onset colorectal cancer.

3600 Background: Sporadic young onset colorectal cancer (YOCRC, ages 30-49) is a public health crisis with a persistent rise in incidence globally. While a proportion of patients (pts) develop YOCRC due to hereditary predisposition, the majority develop sporadic microsatellite stable (MSS) colorectal cancer with limited options beyond standard of care in advanced settings. We report the early phase clinical trial experience at a large academic cancer center to elucidate clues regarding molecular landscape and impact of clinical trials in refractory MSS YOCRC. Methods: Patient and clinical characteristics were summarized using descriptive statistics. Kaplan-Meier method was used to estimate the probabilities of overall survival (OS) and progression free survival (PFS). Log-rank tests were used to assess the differences in OS and PFS between subgroups. Cox proportional hazards regression models were fit to assess the association between OS or PFS and patient characteristics. Statistical analyses were performed using SAS and Splus. Results: 240 MSS YOCRC pts were analyzed. Median age 42.8 (20.5-49), &gt; 80% were white and only 10% black. 21% received at least 3 lines of therapy. The top five mutations were TP53, KRAS, APC, PI3CKA and BRAFV600E. Median OS was 39.2 months (95% CI: 34.8 – 42.5 months). CTNNB1 mutation was associated with a lower risk of death (HR = 0.28, 95% CI: 0.09 – 0.87, p-value = 0.03) while BRAFV600E mutation was associated with an increased risk (HR = 3.28, 95% CI: 2.00 – 5.38, p-value &lt; 0.001). Multivariable Cox model for OS revealed both CTNNB1 and BRAFV600E mutations are significant prognostic factors for OS, unlike KRAS. There was no difference in OS or PFS among pts who entered a mutation specific clinical trial vs. those enrolled on an unmatched clinical trial (p = 0.35, p = 0.68, respectively, log-rank test). Median PFS was 1.9 months (95% CI: 1.8 – 2.1 months). CTNNB1 mutation was associated with a lower risk of progression/death (HR = 0.29, 95% CI: 0.09 – 0.92, p-value = 0.04) while NRAS mutation was associated with an increased risk (HR = 2.13, 95% CI:1.19– 3.80, p-value = 0.01). Among 145 pts who have data on response, 9 had partial response, 41 had stable disease and 95 had progressive disease. BRAFV600E mutation is associated with a higher probability of response (OR = 6.89, 95% CI: 1.64 – 28.94, p-value = 0.01) and pts enrolled on matched clinical trials had a higher probability of response (OR = 6.23; 95% CI: 1.24 – 31.09, p-value = 0.03). However, increased response did not translate to improved OS. No survival differences were appreciated based on a pts race or BMI. Conclusions: CTNNB1, BRAFV600E &amp; NRAS mutations may have prognostic implications in YOCRC. Pts enrolled on mutation specific clinical trials did not achieve improved outcomes compared to unselected trials, highlighting aggressive biology, current lack of therapeutic targets and need for novel drug development in sporadic YOCRC.

Actigraphy sleep patterns in presymptomatic Alzheimer’s Disease: the potential role of neuroinflammation

AbstractBackgroundBoth short and long sleep duration have been associated with increased risk of developing Alzheimer’s Disease (AD). While short sleep has been hypothesized to be a risk factor promoting neurodegenerative processes. Long sleep has been viewed as a marker of ongoing neurodegeneration, potentially as a result of neuroinflammation. The objective of the study is to evaluate sleep patterns measured with actigraphy close to expected symptom onset in association with neuroinflammatory biomarkers. We leveraged the PREVENT‐AD cohort in which participants with a parental history of sporadic AD are studied before clinical onset.Method203 participants (age: 68.5±5.4 years, 151 women) free of dementia were tested with a week of actigraphy. Nighttime sleep duration, time in bed, sleep latency, sleep efficiency, and number of sleep bouts were calculated using the Actiware scoring algorithm (medium threshold). The standard deviation of these characteristics was calculated across actigraphy days to assess day‐to‐day variability. Years to expected onset was calculated by the number of years remaining before the age of clinical onset of a parent, or the earliest age of clinical onset if both parents developed AD. A subset of 100 participants underwent a lumbar puncture, and IL‐6 and MCP‐1 levels were assessed using OLINK technology in cerebrospinal fluid (CSF). The association between sleep characteristics, years to expected onset and inflammatory markers was assessed using linear regressions adjusted for age, sex, and time interval between measurements.ResultBeing closer to expected onset was associated with longer nighttime sleep duration (b = ‐0.19, p = 0.015) and lower sleep bouts day‐to‐day variability (b = 0.17, p = 0.027). Higher CSF IL‐6 was associated with longer sleep duration and time in bed (b = 0.30, p = 0.006; b = 0.24, p = 0.028), whereas higher MCP‐1 was associated with longer nighttime sleep duration (b = 0.25, p = 0.019). Higher CSF MCP‐1 levels were associated with lower sleep bouts day‐to‐day variability and shorter sleep onset latency only in those within 10 years of expected onset (interaction p = 0.012 and 0.061; b = ‐0.31, p = 0.043; b = ‐0.31, p = 0.047).ConclusionProximity to parental onset of sporadic AD onset was associated with a longer sleep profile that is more consolidated and stable, which may be due to proinflammatory processes.

Brain Amyloid in Sporadic Young Onset Alzheimer's Disease.

Controversy exists as to the role of the amyloid-β (Aβ) peptide in the pathophysiology of Alzheimer's disease (AD). To clarify the effect of age on Aβ deposition in sporadic AD by exploring the degree of amyloid burden in patients with sporadic young onset AD (YOAD). Patients were diagnosed with YOAD with dementia starting before the age of 65 years (N = 42; males = 20, females = 22). A cross-sectional analysis of amyloid binding using positron emission tomography (PET) imaging was performed using the C-Pittsburgh Compound B (PiB). The global standardized uptake value ratios (gSUVR) were examined using the Wilcoxon two-sample test, as were the cognitive scores between disease and healthy control populations. Differences in PiB retention in different anatomical areas were compared using the Kruskal-Wallis test. The contrast in APOE genotyping between groups was calculated with Fisher's Exact Test. Women had a median gSUVR = 2.68±0.73 and 73% had at least one APOE ɛ4 allele. Men had gSUVR = 2.37±0.54, with 80% having at least one APOE ɛ4 allele. The gSUVRs were significantly higher than the control populations for men and women and had significantly greater frequency of APOE ɛ4. Men and women analyzed together had significantly greater amyloid burden and APOE ɛ4 allele frequencies than controls, but no differences existed between them in gSUVR nor in the anatomical distribution of amyloid uptake. Men and women with YOAD have greater amyloid uptake than controls and have more APOE ɛ4 alleles. Our findings suggest that the Aβ peptide is operational in young onset dementia and driven by the APOE ɛ4 allele.

Detection of rare genetic variations in the promoter regions of the ATG16L gene in Parkinson's patients

Mutations in the ATG genes have been related to impair autophagic function, contributing to the sporadic onset of Parkinsońs Disease (PD). However, scarce studies have been performed about ins/del within the regulatory domains of the autophagy genes in sporadic PD patients. This study was aimed to found ins/del within part of the crucial core autophagy promotor gene region of the ATG16L1 in a groups of sporadic PD patients. After developing a genetic marker to find ins/del using fragment size analysis, a rare mutation by insertion (0.45%) was reported in the patients. This mutation was characterized by sequencing. No others ins/del were found. As a results, the frequency of this insertion should be considered as a rare genetic variant. An in silico analysis also highlighting the usefulness of a search GDV which revealed multiples ins/del within ATG16L1 promoter. Furthermore, these genetic insertions could be found in patients with sporadic PD in the ATG161L promoter gene. When a breakpoint as deletions, insertions or tandem duplication are located within a functional gene interruption of the gene and a loss of function was expected but removing or altering in the regulatory sequence can influence the expression or the regulation of a nearby gene which may impair healthy due to dosage effects in sporadic diseases.

Spiny keratoderma: A review of case reports and histopathological descriptions.

Spiny keratoderma (SpK) is a rare skin condition characterized by spine-like papules on the palms and soles. The condition is identified under several names such as "music box spine keratosis" and "palmoplantar filiform hyperkeratosis," creating ambiguity in the diagnostic and histopathologic features of the disease. In this study, we reviewed 84 cases of SpK to examine patient demographics, medical history, clinical and histopathological descriptions, and sporadic versus hereditary onset. Notably, the most used histopathological terms were "parakeratosis" and "hypogranulosis," and the most used clinical terms were "spine" and "hyperpigmented." The average age at presentation was 60.1 years with the majority of cases in males. Only 29.8% of cases were associated with a family history of SpK and underlying malignancies were present in 28.6% of cases. This review investigates the frequency of histopathologic and clinical terms used to describe SpK to provide insight into the clinical and histopathological characteristics of this rarely reported condition.

IPSC-Derived Striatal Medium Spiny Neurons from Patients with Multiple System Atrophy Show Hypoexcitability and Elevated α-Synuclein Release

Multiple system atrophy of the parkinsonian type (MSA-P) is a rare, fatal neurodegenerative disease with sporadic onset. It is still unknown if MSA-P is a primary oligodendropathy or caused by neuronal pathophysiology leading to severe, α-synuclein-associated neurodegeneration, mainly in the striatum. In this study, we generated and differentiated induced pluripotent stem cells (iPSCs) from patients with the clinical diagnosis of probable MSA-P (n = 3) and from three matched healthy controls into GABAergic striatal medium spiny neurons (MSNs). We found a significantly elevated release and neuronal distribution for α-synuclein, as well as hypoexcitability in the MSNs derived from the MSA-P patients compared to the healthy controls. These data suggest that the striatal hypoexcitable neurons of MSA-P patients contribute to a pathological α-synuclein burden which is likely to spread to neighboring cells and projection targets, facilitating disease progression.

Characterization of Early Alzheimer's Disease-Like Pathological Alterations in Non-Human Primates with Aging: A Pilot Study.

Sporadic or late onset Alzheimer's disease (LOAD) is a multifactorial neurodegenerative disease with aging the most known risk factor. Non-human primates (NHPs) may serve as an excellent model to study LOAD because of their close similarity to humans in many aspects including neuroanatomy and neurodevelopment. Recent studies reveal AD-like pathology in old NHPs. In this pilot study, we took advantage of brain samples from 6 Cynomolgus macaques that were divided into two groups: middle aged (average age 14.81 years) and older (average age 19.33 years). We investigated whether AD-like brain pathologies are present in the NHPs. We used immunohistochemical method to examine brain Aβ pathology and neuron density. We applied biochemical assays to measure tau phosphorylation and multiple signaling pathways indicated in AD. We performed electron microscopy experiments to study alterations of postsynaptic density and mitochondrial morphology in the brain of NHPs. We found multiple AD-like pathological alteration in the prefrontal cortex (but not in the hippocampus) of the older NHPs including tau hyperphosphorylation, increased activity of AMP-activated protein kinase (AMPK), decreased expression of protein phosphatase 2A (PP2A), impairments in mitochondrial morphology, and postsynaptic densities formation. These findings may provide insights into the factors contributing to the development of LOAD, particularly during the early stage transitioning from middle to old age. Future endeavors are warranted to elucidate mechanisms underlying the regional (and perhaps cellular) vulnerability with aging and the functional correlation of such pathological changes in NHPs.

Can We Treat Neurodegenerative Proteinopathies by Enhancing Protein Degradation?

Neurodegenerative proteinopathies are defined as a class of neurodegenerative disorders, with either genetic or sporadic age-related onset, characterized by the pathological accumulation of aggregated protein deposits. These mainly include Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD) as well as frontotemporal lobar degeneration (FTLD). The deposition of abnormal protein aggregates in the brain of patients affected by these disorders is thought to play a causative role in neuronal loss and disease progression. On that account, the idea of improving the clearance of pathological protein aggregates has taken hold as a potential therapeutic strategy. Among the possible approaches to pursue for reducing disease protein accumulation, there is the stimulation of the main protein degradation machineries of eukaryotic cells: the ubiquitin proteasomal system (UPS) and autophagy lysosomal pathway (ALP). Of note, several clinical trials testing the efficacy of either UPS- or ALP-active compounds are currently ongoing. Here, we discuss the main gaps and controversies emerging from experimental studies and clinical trials assessing the therapeutic efficacy of modulators of either the UPS or ALP in neurodegenerative proteinopathies, to gather whether they may constitute a real gateway from these disorders. © 2022 International Parkinson and Movement Disorder Society.

Accelerated DNA Methylation Age of the TARDBP 3’UTR in the Motor Cortex is Associated with Age of Sporadic ALS Onset. (P1-1.Virtual)

Accelerated DNA Methylation Age of the TARDBP 3’UTR in the Motor Cortex is Associated with Age of Sporadic ALS Onset. (P1-1.Virtual)

Insulin Enhances Gene Expression of Midnolin, a Novel Genetic Risk Factor for Parkinson's Disease, via Extracellular Signal-Regulated Kinase, Phosphoinositide 3-Kinase and Multiple Transcription Factors in SH-SY5Y Cells.

Parkinson's disease (PD) is the second most common neurodegenerative disease. Although many monogenic variants have been identified that cause familial PD, most cases are sporadic and the mechanisms of sporadic PD onset remain unclear. We previously identified midnolin (MIDN) as a novel genetic risk factor for PD in a Japanese population. MIDN copy number loss was strongly associated with sporadic PD, which was replicated in a British population. Furthermore, suppression of MIDN expression in rat pheochromocytoma cells inhibits neurite outgrowth and expression of Parkin ubiquitin ligase. However, the detailed molecular mechanisms of MIDN expression are unknown. We, therefore, investigated the molecular mechanism of MIDN expression in human neuroblastoma SH-SY5Y cells. We found that MIDN expression was promoted by insulin via extracellular-signal regulated kinase1/2 and phosphoinositide 3-kinase-dependent pathways. In addition, MIDN promoter activity was enhanced by mutations at transcription factor AP-2 consensus sequences and reduced by mutations at cAMP response element-binding protein and activator protein 1 (AP-1) consensus sequences. The dominant-negative cAMP response element-binding protein mutant did not block MIDN promoter activity, but both the pharmacological inhibitor and decoy oligodeoxynucleotide for AP-1 significantly blocked its activity. Additionally, DNA binding of c-FOS and c-JUN to the AP-1 consensus sequence in the MIDN promoter was enhanced by insulin as determined by chromatin immunoprecipitation, which suggested that AP-1 positively regulated MIDN expression. Taken together, this study reveals molecular mechanisms of MIDN gene expression induced by insulin in neuronal cells, and drugs which promote MIDN expression may have potential to be a novel medicine for PD. SIGNIFICANCE STATEMENT: We demonstrated that insulin promotes midnolin expression via extracellular-signal regulated kinase 1/2 and phosphoinositide 3-kinase pathways. Furthermore, we identified the important region of the MIDN promoter and showed that transcription factors, including activator protein 1, positively regulate MIDN expression, whereas transcription factor AP-2 negatively regulates basal and insulin-induced MIDN expression. We believe that our observations are important and that they contribute to the development of novel drugs to treat Parkinson's disease.

Age of Symptom Onset and Longitudinal Course of Sporadic Alzheimer's Disease, Frontotemporal Dementia, and Vascular Dementia: A Systematic Review and Meta-Analysis.

Understanding how the age of dementia symptom onset affects the longitudinal course of dementia can assist with prognosis and care planning. To synthesize evidence regarding the relationship of age of symptom onset with the longitudinal course of sporadic Alzheimer's disease (AD), vascular dementia (VaD), and frontotemporal dementia (FTD). We searched Medline, CINAHL, Embase, PsycINFO, PubMed, and Scopus for longitudinal studies that examined the impact of sporadic AD, VaD, or FTD symptom onset age on measures of cognition, function, or behavioral symptoms. Studies that examined age at diagnosis only were excluded. Quantitative meta-analysis was conducted where studies reported sufficient data for pooling. Thirty studies met all inclusion criteria (people with AD (n = 26), FTD (n = 4)) though no studies examined VaD. Earlier onset of AD was associated with more rapid annual cognitive decline (estimate = -0.07; 95% CI -0.14 to 0.00; p = 0.045). Most studies that stratified their sample reported that younger AD onset (usually < 65 years) was associated with more rapid cognitive decline. Other evidence was inconclusive. Younger people with AD appear to have a poorer prognosis in terms of faster cognitive decline than older people with AD. More research is required to determine the impact of symptom onset age in VaD and FTD, and on functional decline in all dementias.