Developing a novel immune infiltration-associated mitophagy prediction model for amyotrophic lateral sclerosis using bioinformatics strategies.

Background: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease, which leads to muscle weakness and eventual paralysis. Numerous studies have indicated that mitophagy and immune inflammation have a significant impact on the onset and advancement of ALS. Nevertheless, the possible diagnostic and prognostic significance of mitophagy-related genes associated with immune infiltration in ALS is uncertain. The purpose of this study is to create a predictive model for ALS using genes linked with mitophagy-associated immune infiltration. Methods: ALS gene expression profiles were downloaded from the Gene Expression Omnibus (GEO) database. Univariate Cox analysis and machine learning methods were applied to analyze mitophagy-associated genes and develop a prognostic risk score model. Subsequently, functional and immune infiltration analyses were conducted to study the biological attributes and immune cell enrichment in individuals with ALS. Additionally, validation of identified feature genes in the prediction model was performed using ALS mouse models and ALS patients. Results: In this study, a comprehensive analysis revealed the identification of 22 mitophagy-related differential expression genes and 40 prognostic genes. Additionally, an 18-gene prognostic signature was identified with machine learning, which was utilized to construct a prognostic risk score model. Functional enrichment analysis demonstrated the enrichment of various pathways, including oxidative phosphorylation, unfolded proteins, KRAS, and mTOR signaling pathways, as well as other immune-related pathways. The analysis of immune infiltration revealed notable distinctions in certain congenital immune cells and adaptive immune cells between the low-risk and high-risk groups, particularly concerning the T lymphocyte subgroup. ALS mouse models and ALS clinical samples demonstrated consistent expression levels of four mitophagy-related immune infiltration genes (BCKDHA, JTB, KYNU, and GTF2H5) with the results of bioinformatics analysis. Conclusion: This study has successfully devised and verified a pioneering prognostic predictive risk score for ALS, utilizing eighteen mitophagy-related genes. Furthermore, the findings indicate that four of these genes exhibit promising roles in the context of ALS prognostic.

Gender-specific association of uric acid and survival in sporadic amyotrophic lateral sclerosis patients.

OBJECTIVE: To investigate the relationship between serum uric acid (UA) and survival in sporadic amyotrophic lateral sclerosis (sALS) patients. METHOD: A total of 801 sporadic amyotrophic lateral sclerosis (sALS) patients fulfilled the revised El Escorial criteria were enrolled and followed up in the study. Baseline clinical data and laboratory variables including gender, age, age of onset, site of onset, disease duration, body mass index (BMI), uric acid (UA), creatinine (Cr), and creatine kinase (CK) were collected during enrollment. Multivariate Cox regression models were used to evaluate the survival-related factors after adjustment for confounders. RESULTS: The serum UA level was significantly lower in female patients than that in male patients (243.5 vs 314.9 µmol/L, p < 0.001). Gender, BMI, Cr, CK were significantly associated with the level of uric acid according to the linear regression analysis. In the multivariate Cox regression analysis, higher serum UA level (>268.0 µmol/L) was an independent protective factor for prolonged survival among female patients (HR = 0.69, P = 0.042) after adjustment for confounders. CONCLUSION: The present study provided further support that higher UA was a protective factor for survival in sALS patients, especially in female.

Evaluating the causal association between microRNAs and amyotrophic lateral sclerosis.

BACKGROUND: Currently, miRNAs are involved in the development of amyotrophic lateral sclerosis (ALS), and identifying circulating miRNAs that are causally associated with ALS risk as biomarkers is imperative. METHODS: We performed a two-sample Mendelian randomization study to evaluate the causal relationship between miRNAs and ALS. Our analysis was conducted using summary statistics from miRNA expression quantitative loci (eQTL) data of the Framingham Heart Study and ALS genome-wide association studies data. Another independent miRNA data was used to further validate. RESULTS: We identified eight unique miRNAs that were causally associated with ALS risk. Using expression data of miRNAs from an independent study, we validated three high-confidence miRNAs, namely hsa-miR-27b-3p, hsa-miR-139-5p, and hsa-miR-152-3p, which might have a potential causal effect on ALS risk. CONCLUSION: We suggested that higher levels of hsa-miR-27b-3p and hsa-miR-139-5p had protective effects on ALS, whereas higher levels of hsa-miR-152-3p might act as a risk factor for ALS. The analytical framework presented in this study helps to understand the role of miRNAs in the development of ALS and to identify the biomarkers for ALS risk.

Assessing the association between white matter lesions and Parkinson's disease.

BACKGROUND: The association between white matter (WM) lesions and Parkinson's disease (PD) was not fully established. We therefore applied Mendelian randomization (MR) analyses to identify the causal effect between white matter lesions and PD. METHODS: We performed a bidirectional two-sample Mendelian randomization (MR) study to investigate the association between three WM phenotypes-white matter hyperintensities (WMH, N = 18,381), fractional anisotropy (FA, N = 17,673), and mean diffusivity (MD, N = 17,467)-with PD (N = 482,730) using summary statistics from genome-wide association studies (GWAS). The inverse variance weighted (IVW), weighted median, MR-Egger, and MR-PRESSO methods were used to evaluate the causal estimate. RESULTS: Significant evidence was suggested that higher MD was associated with a higher PD risk (OR = 1.049, 95% CI = 1.018-1.081, p = 0.022) when the outlier was removed using MR-PRESSO method. Moreover, genetically predicted PD was associated with a lower WMH load (IVW ß = - 0.047, 95% CI = - 0.085 to - 0.009, p = 0.016) and a higher FA (ß = 0.185, 95% CI = 0.021-0.349, p = 0.027). No evidence of pleiotropy was found using MR-Egger intercept. CONCLUSION: Our findings provided genetic support that white matter microstructural integrity lesions might increase the risk of PD. However, genetically predicted PD was potentially associated with a lower load of white matter lesions.

A novel GALC gene mutation associated with adult-onset Krabbe disease: a case report.

To analyze the clinical, imaging, and genetic characteristics of a patient diagnosed with adult-onset Krabbe disease (KD). Clinical and imaging features of the patient were retrospectively reviewed. The patient, a 40-year-old female, presented adult-onset spastic paraplegia. Brain magnetic resonance imaging (MRI) showed white matter hyperintensities along bilateral optic radiations. Colorimetry of galactocerebrosidase enzyme activity showed low enzyme levels. A heterozygous missense mutation: c.1658G>A (p.G553E) and c.1901T>C (p.L634S) was identified in the GALC gene by whole exome sequencing, and was verified by Sanger sequencing. KD should be considered when patients presented adult-onset spastic paraplegia with classical MRI imaging features. Mutation c.1658G>A (p.G553E) was novel in GALC gene and broaden the mutation spectrum.

The protective role of mesencephalic astrocyte-derived neurotrophic factor in endoplasmic reticulum stress in RT4-D6P2T schwannoma sells with the S63del MPZ mutation.

BACKGROUND: Endoplasmic reticulum stress (ERS) occurred in S63del mutant CMT1B mice model, and few drugs has been studied. Mesencephalic astrocyte-derived neurotrophic factor (MANF) can inhibit ERS. This study aimed at investigating the effect of MANF on ERS of RT4-D6P2T schwannoma cells with S63del MPZ Mutation. METHODS: Experimental grouping: blank control group, blank control + MANF group, lentivirus group, lentivirus + MANF group, S63del MPZ group, S63del MPZ + MANF group. CCK8 and Annexin-FITC/PI were used to detect cell proliferation and apoptosis. JC-1 was used to detect ΔΨm. MANF, GRP78 and CHOP mRNA and protein were detected by using RT-qPCR, western blotting and immunofluorescence. ER-Tracker and mito-tracker were used to observe the morphology of endoplasmic reticulum (ER) and mitochondria. RESULTS: Cell proliferation decreased (p < 0.001) and apoptosis increased (p < 0.001) in S63del MPZ group; cell proliferation increased (p = 0.005) and apoptosis decreased (p < 0.001) in S63del MPZ + MANF group. ΔΨm decreased (p < 0.001), MANF, GRP78, CHOP, ATF6, P-PERK/PERK, P-IRE1/IRE1, Bax and Caspase3 increased (p < 0.001) and Bcl2 decreased (p < 0.001) in S63del MPZ group. MANF, GRP78, CHOP, ATF6, P-PERK/PERK, P-IRE1/IRE1, Bax and Caspase3 decreased (p < 0.001) and Bcl2 increased (p < 0.001) in S63del MPZ group. CONCLUSIONS: ERS occurred in RT4-D6P2T cells with S63del MPZ mutation, and MANF exerted protective effect in RT4-D6P2T cells with S63del MPZ mutation.

Screening for SH3TC2 variants in Charcot-Marie-Tooth disease in a cohort of Chinese patients.

Mutations in the SH3TC2 gene cause Charcot-Marie-Tooth disease type 4C (CMT4C), characterized by inherited demyelinating peripheral neuropathy. CMT4C is a common form of CMT4/autosomal recessive (AR) CMT1. This study examined the SH3TC2 variants, investigated genotype-phenotype correlations and explored the frequency of CMT4C in Chinese patients. A total of 206 unrelated patients of Chinese Han descent clinically diagnosed with CMT were recruited. All patients underwent detailed history-taking, neurological examination, laboratory workups, and electrophysiological studies. Genetic analysis was performed via high-throughput target sequencing (NGS). Three patients, one male and two females, were found to carry five SH3TC2 mutations: patient 1 (c.3154C > T, p.R1054X; c.929G > A, p.G310E); Patient 2 (c.2872_2872del, p.S958fs; c.3710C > T, p.A1237V) and Patient 3 (c.2782C > T, p.Q928X; c.929G > A, p.G310E). The c.2872_2872del, c.3710C > T and c.2782C > T variants were not reported before. CMT4C caused by SH3TC2 mutation is a very common type of CMT4/AR CMT1. Three novel mutations, c.2872_2872del, c.3710C > T and c.2782C > T, were found in this study. Combination of clinical phenotype, nerve conduction studies, genetic analysis and bioinformatics analysis are of vital importance in patients suspected as CMT.

Time of symptoms beyond the bulbar region predicts survival in bulbar onset amyotrophic lateral sclerosis.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Spreading pattern and time interval of spreading are getting more and more attention. The aim of present study was to investigate spreading pattern in bulbar onset ALS patients and to explore the relationship between time interval of spreading and survival. METHODS: ALS patients with bulbar onset diagnosed at Chinese PLA General Hospital from January 2015 to December 2018 were recruited. Clinical features including gender, onset age, diagnostic delay, the second involved region (SIR), time of symptoms beyond the bulbar region, forced vital capacity (FVC), ALSFRS-R score, electromyography results, and survival time were retrospectively collected. RESULTS: A total of 96 bulbar onset ALS patients were collected. Overall patients showed female predominance. Median age at onset was 56 years. Median diagnostic delay was 8.5 months. Median time of symptoms beyond the bulbar region (TBBR) was 7 months. Median ALSFRS-R score at baseline was 40. Fifty-six (58.3%) patients' SIR were upper limb, 6 (6.3%) patients' SIR were lower limb, 3 (3.1%) patients' SIR were upper and lower limbs, and 5 (5.2%) patients' SIR were thoracic region. Twenty-six (27.1%) patients did not report SIR. The median survival time of patients with TBBR ≥ 7 months was significantly longer than that with TBBR < 7 month. Multivariate Cox regression showed that onset age and TBBR were prognostic factors. CONCLUSIONS: In bulbar onset ALS patients, cervical region is the second most common SIR. TBBR is an independent prognostic factor.

Genetic and clinical features of Chinese sporadic amyotrophic lateral sclerosis patients with TARDBP mutations.

OBJECTIVES: To investigate the genetic and clinical features of Chinese sporadic amyotrophic lateral sclerosis (SALS) patients with TARDBP mutations, we carried out a genetic analysis in a cohort of 391 SALS patients and explored the clinical manifestations of patients with TARDBP variants. MATERIALS AND METHODS: The coding region of all five coding exons of TARDBP, exons 2-6, were sequenced for mutations in 391 Chinese SALS patients. The clinical features of patients with TARDBP mutations were described and compared with cases in literatures. RESULTS: Two missense mutations in TARDBP gene, c.1132A > G (p.N378D) and c.1147A > G (p.I383V), were detected in three cases, showing a low frequency (0.77%, 3/391) of TARDBP missense mutations in Chinese SALS patients. Based on a retrospective analysis of literatures, p.N378D mutation mainly presents a phenotype of early onset, whereas p.I383V mutation presents pure ALS or ALS alongside semantic variant primary progressive aphasia (svPPA), a type of frontotemporal dementia (FTD). CONCLUSIONS: Our results demonstrate that TARDBP mutation is a rare cause of Chinese SALS patients and expand the spectrum of phenotype. It is implied that genetic analysis of SALS patients plays a crucial role in uncovering the cause of disease, especially for cases developing early onset or alongside FTD.

Mutation Screening of the GLE1 Gene in a Large Chinese Cohort of Amyotrophic Lateral Sclerosis Patients.

Amyotrophic lateral sclerosis (ALS) is a fatal progressive neurodegenerative disease involving the upper and lower motor neurons of the spinal cord, brainstem, and cerebral cortex. At least 30 genes have been implicated in familial ALS (fALS) and sporadic ALS (sALS). Kaneb et al. (2015) first carried out a large-scale sequencing study in ALS patients and identified two loss-of-function (LOF) variants in the GLE1 gene. The LOF mutation-induced disruption of RNA metabolism through the haploinsufficiency mechanism is implicated in ALS pathogenesis. A total of 628 ALS patients and 522 individuals without neurodegenerative disorders were enrolled in this study to explore the GLE1 gene contribution to ALS in the Chinese population. All 16 exons and the flanking intron of GLE1 were screened by Sanger sequencing. In total, we identified seven rare GLE1 coding variants, including one novel nonsense mutation and six rare missense mutations in 628 ALS patients. The frequency of GLE1 LOF mutations was 0.16% (1/628) among Chinese sALS patients, implying that it is an uncommon genetic determinant of ALS in Chinese patients. Additionally, the rare missense variants in the hCG1-binding domain of GLE1 impairing the distribution of the hGle1B isoform at the nuclear pore complex (NPC) region may be involved in the pathogenesis of ALS.

The increase in CSF total protein and immunoglobulins in Chinese patients with sporadic amyotrophic lateral sclerosis: A retrospective study.

OBJECTIVE: The objective of this study was to evaluate total protein (TP) in the cerebrospinal fluid (CSF) and immunoglobulins in the serum and CSF in patients with sporadic amyotrophic lateral sclerosis (sALS). We also assessed the correlations of these variables with sALS progression and severity and estimated their roles in predicting prognosis. METHODS: We retrospectively collected data on CSF TP and immunoglobulins in the CSF and serum, including immunoglobulin G, immunoglobulin A and immunoglobulin M, from 326 sALS patients. The relationships between these variables and clinical features, including sex, age, disease duration, site of onset, respiratory function and survival time, were analysed by Wilcoxon's nonparametric tests. Kaplan-Meier and Cox proportional hazards models were used to explore whether levels of TP and immunoglobulins in the CSF were independently correlated with the survival time of patients with ALS. RESULTS: The CSF TP was elevated in 55% of the patients. The median CSF TP was 417.7 (349.4-539.5) mg/L, and 6 patients (2%) had a CSF TP level greater than 1000 mg/L. The CSF TP levels were significantly higher in male patients than in female patients (p<.001). In females, the CSF TP had positive associations with onset age (rho =0.196, p = .021) and disease progression rate (DPR) (rho =0.230, p = .035) but negative associations with disease duration (rho = -0.204, p = .016) and revised ALS functional rating scale (ALSFRS-R) (rho = -0.288, p = .008). The ALSFRS-R scores of male patients were negatively correlated with the s-IgM levels (rho = -0.562, p = .005). Onset age was negatively associated with the s-IgM levels (rho = -0.534, p = .005) in females. Kaplan-Meier survival analyses showed that no correlations were found between survival time and the levels of TP and immunoglobulins in the CSF. CONCLUSION: Elevated levels of TP and immunoglobulins in the CSF suggest impaired blood-brain barrier (BBB) function and immune responses in the CNS of ALS patients. Higher CSF TP levels were associated with later onset age, a shorter disease duration and worse disease severity in females. The changes in the levels of CSF TP and s-IgM might indicate the severity of the disease in some ALS patients.

Target-Catalyzed Assembly of Pyrene-Labeled Hairpins for Exponentially Amplified Biosensing.

Rapid and sensitive detection of nucleic acids is vital for disease diagnosis. This work designed an enzyme-free isothermal strategy for rapid exponential signal amplification through target-triggered catalytic hairpin assembly (CHA) to induce the spatially sensitive fluorescent signal of the pyrene excimer. Functionally, this system consisted of three pyrene labelled hairpins (H1, H2, and H3) and one catalyst DNA C. In the presence of C, the CHA was activated to generate intermediate I, which contained a single-stranded region identical to the C sequence for initiating the second cycle of CHA to obtain 2I and thus achieved the exponential formation of I along with the switching of pyrene excimer. The fluorescent signal of the pyrene excimer could be further enhanced via the inclusion of γ-cyclodextrin and showed a linear increase upon increasing logarithm of C concentration. Through the introduction of a helping hairpin H4-containing C sequence and a region specific to the target, this strategy could be extended to realize the quick and sensitive detection of different analytes. Using dengue virus RNA as an analyte model, the proposed fluorescent method showed a linear range from 0.1 to 50 nM with a limit of detection of 0.048 nM at 3σ and good selectivity. The excellent performance and convenient operation demonstrated its promising application in clinical disease diagnosis.

Motion of Enzyme-Powered Microshell Motors.

Microshells are attractive in constructing bubble-propelled micromotors due to the lower energy consumption for bubbles forming on a concave surface. In this work, enzyme-powered microshell motors were fabricated on multimetallic (Au/Ag/Au) microshells along with the modification of catalase on its concave surface. The catalase triggered the decomposition of hydrogen peroxide to oxygen gas, hence propelling the autonomous motion of microshell motors. A size-dependent motion behaviour was observed for the microshell motors in the form of slow tremble and fast translation motion for a size smaller and larger than 5 µm, respectively, according to the size, generation efficiency and ejection mechanism of bubbles and the intensity of Brownian motion. In addition, the effect of fuel concentration on the motion speed of microshells was dependent on whether the bubble generation was affected by the limited mass transfer in the microshell space. These findings play an important role for the design of microshell motors.

Elevated serum ferritin level as a predictor of reduced survival in patients with sporadic amyotrophic lateral sclerosis in China: a retrospective study.

Objective: The objective of this study was to compare iron metabolic variables in the serum and cerebrospinal fluid (CSF) of patients with sporadic amyotrophic lateral sclerosis (sALS) with those of patients with multiple system atrophy (MSA) and control subjects. We also assessed the correlations of these variables with sALS progression and severity and estimated their roles in predicting prognosis. Methods: We retrospectively collected iron metabolic parameters, including serum levels of iron, ferritin, transferrin levels and total iron binding capacity and the CSF level of ferritin, from 435 sALS patients, 176 MSA patients and 431 control subjects. Results: Serum ferritin levels were significantly higher in the sALS group compared with the MSA and control groups in both males (p = 0.001 and p < 0.0001, respectively) and females (p = 0.034 and p < 0.0001, respectively). However, serum transferrin levels were significantly lower in females of the sALS group compared with the MSA (p = 0.016) and control (p = 0.015) groups. The CSF ferritin level and the serum levels of total iron binding capacity and iron were similar among the sALS, MSA and control groups. Survival analysis demonstrated that higher serum ferritin levels were predictors of reduced survival of sALS patients. No correlations between iron metabolic variables and clinical parameters were found. Conclusion: An elevated serum ferritin level is associated with reduced survival of sALS patients. However, the levels of iron metabolic parameters were not associated with clinical deterioration or disease severity at diagnosis.