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Abstract Background Using neuroimaging techniques, growing evidence has suggested that the choroid plexus (CP) volume is enlarged in multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Notably, the CP has been suggested to play an important role in inflammation-induced CNS damage under disease conditions. However, to our knowledge, no study has investigated the relationships between peripheral inflammation and CP volume in sporadic ALS patients. Thus, in this study, we aimed to verify CP enlargement and explore its association with peripheral inflammation in vivo in independent ALS cohorts. Methods Based on structural MRI data, CP volume was measured using Gaussian mixture models and further manually corrected in two independent cohorts of sporadic ALS patients and healthy controls (HCs). Serum inflammatory protein levels were measured using a novel high-sensitivity Olink proximity extension assay (PEA) technique. Xtreme gradient boosting (XGBoost) was used to explore the contribution of peripheral inflammatory factors to CP enlargement. Then, partial correlation analyses were performed. Results CP volumes were significantly higher in ALS patients than in HCs in the independent cohorts. Compared with HCs, serum levels of CRP, IL-6, CXCL10, and 35 other inflammatory factors were significantly increased in ALS patients. Using the XGBoost approach, we established a model-based importance of features, and the top three predictors of CP volume in ALS patients were CRP, IL-6, and CXCL10 (with gains of 0.24, 0.18, and 0.15, respectively). Correlation analyses revealed that CRP, IL-6, and CXCL10 were significantly associated with CP volume in ALS patients (r = 0.462 ∼ 0.636, p

Abstract Background The interplay between metabolic disorders and chronic kidney disease (CKD) has been well-documented. However, the connection between CKD and atherogenic index of plasma (AIP) remains understudied. This research delves into the correlation between these two factors, aiming to shed new light on their potential association. Methods The relationship between AIP and CKD was evaluated using a weighted multivariate logistic regression model, and the curvilinear relationship between AIP and CKD was explored through smooth curve fitting. We engaged a recursive partitioning algorithm in conjunction with a two-stage linear regression model to precisely determine the inflection point. By conducting stratified analyses, the heterogeneity within subpopulations was explored. Results In the regression model that accounted for all covariates, ORs (95% CI) for the association between CKD and AIP were 1.12 (0.91, 1.36), indicating no significant association between AIP and CKD. However, sensitivity analyses suggested that the relationship between them may be non-linear. Smooth curve analysis confirmed the non-linear relationship between AIP and CKD, identifying an inflection point at -0.55. Below this threshold, AIP exhibited a significant inverse correlation with CKD. Conversely, above this threshold, a pronounced positive correlation was detected. Stratified analyses elucidated that a non-linear association between AIP and CKD was observed among female participants and those aged 50 and above. Conclusion We found a curvilinear relationship between chronic kidney disease and atherogenic index of plasma.

Abstract Background Mitochondrial tRNA (mt-tRNA) variants have been found to cause disease. Post-transcriptional queuosine (Q) modifications of mt-tRNA can promote efficient mitochondrial mRNA translation. Q modifications of mt-tRNAAsn have recently been identified. Here, the therapeutic effectiveness of queuine was investigated in cells from patients with mt-tRNAAsn variants. Methods Six patients (from four families) carrying mt-tRNAAsn variants were included in the study. Queuine levels were quantified by mass spectrometry. Clinical, genetic, histochemical, biochemical, and molecular analysis was performed on muscle tissues and lymphoblastoid cell lines (LCLs) from patients to investigate the pathogenicity of the novel m.5708 C > T variant. The use of queuine in mitigating mitochondrial dysfunction resulting from the mt-tRNAAsn variants was evaluated. Results The variants included the m.5701 delA, m.5708 C > T, m.5709 C > T, and m.5698 G > A variants in mt-tRNAAsn. The pathogenicity of the novel m.5708 C > T variant was confirmed, as demonstrated by a decreased steady-state level of mt-tRNAAsn, mtDNA-encoded protein levels, oxygen consumption rate (OCR), and the respiratory complex activity. Notably, the serum queuine level was significantly reduced in these patients and in vitro queuine supplementation was found to restore the reductions in mitochondrial protein activities, mitochondrial membrane potential, OCR, and increases in reactive oxygen species. Conclusions The study not only confirmed the pathogenicity of the m.5708 C > T variant but also explored the therapeutic potential of queuine in individuals with mt-tRNAAsn variants. The recognition of the novel m.5708 C > T variant’s pathogenic nature contributes to our comprehension of mitochondrial disorders. Furthermore, the results emphasize queuine supplementation as a promising approach to enhance the stability of mt-tRNAAsn and rescue mitochondrial dysfunction caused by mt-tRNAAsn variants, indicating potential implications for the development of targeted therapies for patients with mt-tRNAAsn variants.

Abstract Background Late-onset Pompe disease (LOPD) is mainly characterized by progressive limb-girdle muscle weakness and respiratory impairment, whereas stroke and cerebrovascular abnormalities have been insufficiently studied in LOPD. This study aimed to evaluate the frequency and pattern of intracranial artery and brain parenchyma abnormalities in LOPD patients. Results Neuroimaging data from 30 Chinese adult LOPD patients were collected from our center. Seven patients (7/30) had acute cerebral infarction or hemorrhage. Brain magnetic resonance angiography (MRA) or computed tomography angiography (CTA) revealed artery abnormalities in 23 patients (23/30). Dilative arteriopathy was found in 19 patients (19/30), with vertebrobasilar dolichoectasia found in 17 patients and dilatation of the anterior circulation arteries found in 8 patients. The maximum diameter of the basilar artery was correlated with disease duration (p

Abstract Background Mitochondrial diseases (MDs) can be caused by single nucleotide variants (SNVs) and structural variants (SVs) in the mitochondrial genome (mtDNA). Presently, identifying deletions in small to medium-sized fragments and accurately detecting low-percentage variants remains challenging due to the limitations of next-generation sequencing (NGS). Methods In this study, we integrated targeted long-range polymerase chain reaction (LR-PCR) and PacBio HiFi sequencing to analyze 34 participants, including 28 patients and 6 controls. Of these, 17 samples were subjected to both targeted LR-PCR and NGS to compare the mtDNA variant detection efficacy. Results Among the 28 patients tested by long-read sequencing (LRS), 2 patients were found positive for the m.3243 A > G hotspot variant, and 20 patients exhibited single or multiple deletion variants with a proportion exceeding 4%. Comparison between the results of LRS and NGS revealed that both methods exhibited similar efficacy in detecting SNVs exceeding 5%. However, LRS outperformed NGS in detecting SNVs with a ratio below 5%. As for SVs, LRS identified single or multiple deletions in 13 out of 17 cases, whereas NGS only detected single deletions in 8 cases. Furthermore, deletions identified by LRS were validated by Sanger sequencing and quantified in single muscle fibers using real-time PCR. Notably, LRS also effectively and accurately identified secondary mtDNA deletions in idiopathic inflammatory myopathies (IIMs). Conclusions LRS outperforms NGS in detecting various types of SNVs and SVs in mtDNA, including those with low frequencies. Our research is a significant advancement in medical comprehension and will provide profound insights into genetics.

Abstract Inherited deficiency of thymidine phosphorylase (TP), encoded by TYMP, leads to a rare disease with multiple mitochondrial DNA (mtDNA) abnormalities, mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). However, the impact of TP deficiency on lysosomes remains unclear, which are important for mitochondrial quality control and nucleic acid metabolism. Muscle biopsy tissue and skin fibroblasts from MNGIE patients, patients with m.3243 A > G mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS) and healthy controls (HC) were collected to perform mitochondrial and lysosomal functional analyses. In addition to mtDNA abnormalities, compared to controls distinctively reduced expression of LAMP1 and increased mitochondrial content were detected in the muscle tissue of MNGIE patients. Skin fibroblasts from MNGIE patients showed decreased expression of LAMP2, lowered lysosomal acidity, reduced enzyme activity and impaired protein degradation ability. TYMP knockout or TP inhibition in cells can also induce the similar lysosomal dysfunction. Using lysosome immunoprecipitation (Lyso- IP), increased mitochondrial proteins, decreased vesicular proteins and V-ATPase enzymes, and accumulation of various nucleosides were detected in lysosomes with TP deficiency. Treatment of cells with high concentrations of dThd and dUrd also triggers lysosomal dysfunction and disruption of mitochondrial homeostasis. Therefore, the results provided evidence that TP deficiency leads to nucleoside accumulation in lysosomes and lysosomal dysfunction, revealing the widespread disruption of organelles underlying MNGIE. Graphical Abstract

Abstract Background Using in vivo neuroimaging techniques, growing evidence has demonstrated that the choroid plexus (CP) volume is enlarged in patients with several neurodegenerative diseases, including Alzheimer’s disease and Parkinson’s disease. However, although animal and postmortem findings suggest that CP abnormalities are likely important pathological mechanisms underlying amyotrophic lateral sclerosis (ALS), the third most common neurodegenerative disease, no available study has been conducted to thoroughly assess CP abnormalities and their clinical relevance in vivo in ALS patients to date. Thus, we aimed to determine whether in vivo CP enlargement may occur in ALS patients. We also aimed to identify the relationships of CP volume with clinical disabilities and blood-CSF barrier (BCSFB) permeability in ALS patients. Methods In this retrospective study, based on structural MRI data, CP volume was assessed using a Gaussian mixture model and underwent further manual correction in 155 ALS patients and 105 age- and sex-matched HCs from October 2021 to April 2023. The ALS Functional Rating Scale-Revised (ALSFRS-R) was used to assess clinical disability. The CSF/serum albumin quotient (Qalb) was used to assess BCSFB permeability. Moreover, all the ALS patients completed genetic testing, and according to genetic testing, the ALS patients were further divided into genetic ALS subgroup and sporadic ALS subgroup. Results We found that compared with HCs, ALS patients had a significantly higher CP volume (p

We used a non-integrated reprogramming approach to establish a human induced pluripotent stem cell (hiPSC) line (INNDSUi004-A) from the skin fibroblasts of a 13-year-old female individual with Congenital Nemaline Myopath. The cells obtained have typical characteristics of embryonic stem cells, show expression of specific pluripotency markers, and can differentiate into three germ layers in vitro. This iPSC cell line has the genetic information of the patient and is a good model for studying disease mechanisms and developing novel therapies.

We obtained skin fibroblasts from a 34-year-old healthy woman and established a human induced pluripotent stem cell (hiPSC) line (INDSUi005-A) using a non-integrated reprogramming approach. The obtained cells have typical characteristics of embryonic stem cells, can express specific pluripotency markers and have the ability to differentiate into three germ layers in vitro. This iPSC cell line can be used as an in vitro model for studying disease mechanisms and developing novel therapies.

ABSTRACT Objective To explore the clinical characteristics of mitochondrial encephalomyopathy, lactic acidosis, and stroke‐like episodes (MELAS) caused by mitochondrial DNA‐encoded complex I subunit (mt‐ND) variants. Methods In this retrospective study, the clinical, myopathological and brain MRI features of patients with MELAS caused by mt‐ND variants (MELAS‐mtND) were collected and compared with those of MELAS patients carrying the m.3243A > G variant (MELAS‐A3243G). Result A total of 18 MELAS‐mtND patients (female: 7; median age: 24.5 years) represented 15.9% (n = 113) of all patients with MELAS caused by mtDNA variants in our neuromuscular center from January 2012 to June 2022. In this MELAS‐mtND cohort, the two most common variants were m.10191 T > C (4/18, 22.2%) and m.13513 G > A (3/18, 16.7%). The most frequent symptoms were seizures (14/18, 77.8%) and muscle weakness (11/18, 61.1%). Compared with 87 MELAS‐A3243G patients, MELAS‐mtND patients were significantly more likely to have a variant that was absent in blood cells (40% vs. 1.4%). Furthermore, MELAS‐mtND patients had a significantly lower MDC score (7.8 ± 2.7 vs. 9.8 ± 1.9); less hearing loss (27.8% vs. 54.0%), diabetes (11.1% vs. 37.9%), and migraine (33.3% vs. 62.1%); less short stature (males ≤ 165 cm; females ≤ 155 cm; 23.1% vs. 60.8%) and higher body mass index (20.4 ± 2.5 vs. 17.8 ± 2.7). MELAS‐mtND patients had significantly more normal muscle pathology (31.3% vs. 4.1%) and fewer RRFs/RBFs (62.5% vs. 91.9%), COX‐deficient fibers/blue fibers (25.0% vs. 85.1%) and SSVs (50.0% vs. 81.1%). Moreover, brain MRI evaluated at the first stroke‐like episode showed significantly more small cortical lesions in MELAS‐mtND patients (66.7% vs. 12.2%). Interpretation Our results suggested that MELAS‐mtND patients have distinct clinical, myopathological and brain MRI features compared with MELAS‐A3243G patients.

Abstract Background Pseudorabies virus (PRV) was thought to only infect animals. Recent studies have shown that it can also infect human. Case presentation We report a case of pseudorabies virus encephalitis and endophthalmitis, diagnosed 89 days after onset, confirmed with intraocular fluid metagenomic next generation sequencing (mNGS) after the result of two cerebrospinal fluid (CSF) mNGS tests were negative. Although treatment with intravenous acyclovir, foscarnet sodium, and methylprednisolone improved the symptoms of encephalitis, significant diagnostic delay resulted in permanent visual loss. Conclusions This case suggests that pseudorabies virus (PRV) DNA in the intraocular fluid may have a higher positivity than that in the CSF. PRV may persist in the intraocular fluid for an extended period and may thus require extended antiviral therapy. Patients with severe encephalitis and PRV should be examined with the focus on pupil reactivity and light reflex. A fundus examination should be performed in patients with a central nervous system infection, specifically, those in a comatose state, to help reduce eye disability.

Abstract Objective Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a rare acquired immune-mediated neuropathy. Although microbial infection is potentially a contributing factor, a causative link between CIDP and microbial infection remains unclear. There is also no definitive biomarker for CIDP diagnostics and therapies. The present study aimed to characterize the serum metabolic profile and gut microbiome structure in CIDP. Methods Targeted metabolomics profiling of serum, using liquid chromatography-mass spectrometry, and metagenomics sequencing of stool samples from a cohort of CIDP and non-CIDP subjects were performed to evaluate serum metabolic profiles and gut microbiome structure in CIDP subjects relative to healthy controls. Results Metabolome data revealed that the bile acids profile was perturbed in CIDP with bile acids and arachidonic acid enriched significantly in CIDP versus non-CIDP controls. Metagenome data revealed that opportunistic pathogens, such as Klebsiella pneumonia and Megamonas funiformis, and genes involved in bacterial infection were notably more abundant in CIDP subjects, while gut microbes related to biotransformation of secondary bile acids were abnormal in CIDP versus non-CIDP subjects. Correlation analysis revealed that changes in secondary bile acids were associated with altered gut microbes, including Bacteroides ovatus, Bacteroides caccae, and Ruminococcus gnavus. Conclusion Bile acids and arachidonic acid metabolism were disturbed in CIDP subjects and might be affected by the dysbiosis of gut microbial flora. These findings suggest that the combination of bile acids and arachidonic acid could be used as a CIDP biomarker and that modulation of gut microbiota might impact the clinical course of CIDP.

Mutations in the ETFDH gene, encoding electron transfer flavoprotein dehydrogenase, have been identified to cause riboflavin-responsive multiple acyl-CoA dehydrogenase deficiency (RR-MADD) (Wen et al., 2010). We performed the generation and characterization of human induced pluripotent stem cell (iPSC) line from skin fibroblasts of a patient with RR-MADD carrying two heterozygous ETFDH mutations (p.D130V and p.A84V). Their pluripotency was verified by the expression of several pluripotency markers on RNA and protein levels and the capability to differentiate into all three germ layers.

BackgroundLAMA2-related limb girdle muscular dystrophy (LGMD R23) is rare. The detailed clinical phenotypes and genetic information associated with LGMD R23 are unknown.MethodsWe conducted a retrospective cross-sectional and longitudinal study on 19 LGMD R23 patients.ResultsNormal early motor development was observed in 84.2% patients. Mild orthopedic complications were observed in 42.1% patients. 36.8% patients had seizures, which is unusually frequent in LGMD. Epilepsy was eventually diagnosed in 26.3% patients. 46.7% patients presented with motor neuropathy. Genetic analysis identified 29 pathogenic variants, with missense and frameshift variants being the most common. The mutant sites were mainly distributed in the N-terminal and G-like domains of laminin. The missense variants are distributed near the N-terminus (exons 3–11), whereas frameshift variants are distributed in exons 12–65. Five patients were diagnosed with epilepsy and all of them harbor at least one missense variants in exon 4. 71.4% variants of patients with motor neuropathy located in the LN domain.ConclusionsMissense variants in exon 4 maybe correlated with epilepsy and variants in the LN domain maybe correlated with motor neuropathy in Chinese patients. Our study expands the clinical and genetic spectrum caused by LAMA2 variations and provides novel genotype-phenotype correlations of LGMD R23.

BackgroundRecent studies have reported that similar to other IgG4 autoimmune diseases, such as muscle-specific kinase antibody-associated myasthenia gravis, most anti-neurofascin-155 (anti-NF155) nodopathies respond well to rituximab treatment, regardless of the dosage. However, there are still a few patients for which rituximab is ineffective for unknown reasons. Currently, there are no studies on the mechanism of ineffective treatment with rituximab.MethodsA 33-year-old Chinese man presenting with numbness, tremor, and muscle weakness for 4 years was recruited for this study. Anti-NF155 antibodies were identified by cell-based assay and confirmed by immunofluorescence assay on teased fibers. The anti-NF155 immunoglobulin (IgG) subclasses were also detected by immunofluorescence assay. Anti-rituximab antibodies (ARAs) were quantitatively analyzed using enzyme-linked immunosorbent assay (ELISA), and peripheral B cell counts were determined by flow cytometry.ResultsThe patient exhibited anti-NF155 IgG4-antibody positivity. After the first round of rituximab infusion, the patient showed stratified outcomes with improvements in numbness, muscle weakness and ambulation. However, after three rounds of rituximab infusion, the patient’s symptoms deteriorated, and the numbness, tremor and muscle weakness returned. No obvious improvement was found after plasma exchange and another round of rituximab treatment. 14 days after the last treatment with rituximab, ARAs were detected. And the titers gradually decreased on day 28 and 60 but remained higher than normal. Peripheral CD19+ B cell counts were less than 1% within the 2-month period following the final rituximab administration.ConclusionsIn this study, ARAs presented in a patient with anti-NF155 nodopathy undergoing rituximab treatment and showed an unfavorable impact on rituximab efficacy. This is the first case to report the occurrence of ARAs in patients with anti-NF155 antibodies. We suggest that ARAs should be tested early during the initial intervention, especially in patients who respond poorly to rituximab treatment. In addition, we believe it is necessary to investigate the association between ARAs and B cell counts, their effect on clinical efficacy, and their potential adverse reactions in a larger cohort of patients with anti-NF155 nodopathy.

Abstract Objective To investigate the clinical features of Han Chinese patients with anti‐neurofascin‐155 (NF155) antibody‐positive neuropathy. Methods We screened 194 patients with peripheral neuropathy for NF155 antibodies using a cell‐based assay (CBA) and teased‐fiber immunofluorescence assay. We summarized the clinical findings of seropositive patients. Results The sera from 17 patients reacted to human embryonic kidney 293 cells transfected with NF155. Eleven of these patients had the immunoglobulin G (IgG) 4 isotype, a younger onset age, tremor, higher levels of cerebrospinal fluid protein, a larger diameter of the lumbosacral nerve root on magnetic resonance imaging, and the distal demyelinating symmetric phenotype. Most patients responded to steroids and rituximab. For the remaining six seropositive patients in CBA, the predominant antibody isotype was IgG3, IgG1, or undetectable, and only one patient with IgG3 showed a positive result in the teased‐fiber immunofluorescence assay. These patients did not share the typical features displayed by patients with the IgG4 isotype. Interpretation In the Han Chinese population, a significant proportion of patients who fulfilled the criteria for chronic inflammatory demyelinating polyradiculoneuropathy diagnosis had anti‐NF155 IgG4 antibody‐positive neuropathy and displayed specific phenotypes. Ambiguous staining patterns may appear, and the potential for false positivity should be considered. For patients who presented with specific phenotypes, identifying antibodies and subtypes involved a significant laboratory workup.

ObjectiveIdiopathic inflammatory myopathies (IIMs) are a heterogeneous group of autoimmune diseases with various subtypes, myositis-specific antibodies, and affect multiple systems. The treatment of IIMs remains challenging, especially for refractory myositis. In addition to steroids and traditional immunosuppressants, rituximab (RTX), a B cell-depleting monoclonal antibody, is emerging as an alternative treatment for refractory myositis. However, the therapeutic response to RTX remains controversial. This meta-analysis aimed to systematically evaluate the efficacy and safety of RTX in patients with IIMs, excluding sporadic inclusion body myositis.MethodsPubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, and WanFang Data were searched for relevant studies. The overall effective rate, complete response rate, and partial response rate were calculated to assess the efficacy of RTX. The incidences of adverse events, infection, severe adverse events, severe infection, and infusion reactions were collected to evaluate the safety of RTX. Subgroup analyses were performed using IIM subtypes, affected organs, continents, and countries. We also performed a sensitivity analysis to identify the sources of heterogeneity.ResultsA total of 26 studies were included in the quantitative analysis, which showed that 65% (95% confidence interval [CI]: 54%, 75%) of patients with IIMs responded to RTX, 45% (95% CI: 22%, 70%) of patients achieved a complete response, and 39% (95% CI: 26%, 53%) achieved a partial response. Subgroup analyses indicated that the overall efficacy rates in patients with refractory IIMs, dermatomyositis and polymyositis, as well as anti-synthetase syndrome were 62%, 68%, and 62%, respectively. The overall efficacy rates for muscle, lungs, and skin involvement were 59%, 65%, and 81%, respectively. In addition, studies conducted in Germany and the United States showed that patients with IIMs had an excellent response to RTX, with an effective rate of 90% and 77%, respectively. The incidence of severe adverse events and infections was 8% and 2%, respectively.ConclusionRTX may be an effective and relatively safe treatment choice in patients with IIMs, especially for refractory cases. However, further verification via randomized controlled trials is warranted.

BackgroundAutoimmune nodopathy with anti-contactin-1 (CNTN1) responds well to rituximab instead of traditional therapies. Although a low-dose rituximab regimen was administered to patients with other autoimmune diseases, such as myasthenia gravis and neuromyelitis optica spectrum disorders, and satisfactory outcomes were obtained, this low-dose rituximab regimen has not been trialed in anti-CNTN1-positive patients.MethodsAnti–CNTN1 nodopathy patients were enrolled in this prospective, open-label, self-controlled pilot study. A cell-based assay was used to detect anti-CNTN1 antibodies and their subclasses in both serum and cerebrospinal fluid. Clinical features were evaluated at baseline, 2 days, 14 days, and 6 months after single low-dose rituximab treatment (600 mg). The titers of the subclasses of anti-CNTN1 antibody and peripheral B cells were also evaluated at baseline, 2 days, and 6 months after the rituximab regimen.ResultsTwo patients with anti–CNTN1 antibodies were enrolled. Both patients had neurological symptoms including muscle weakness, tremor, sensory ataxia, numbness and mild nephrotic symptoms. In the field of neurological symptoms, sensory ataxia markedly improved, and the titer of anti-CNTN1 antibody as well as CD19+ B cells decreased only two days following low-dose rituximab treatment. Other neurological symptoms improved within two weeks of rituximab treatment. At the 6-month follow-up, all neurological symptoms steadily improved with steroid reduction, and both the anti-CNTN1 antibody titer and CD19+ B cells steadily decreased. No adverse events were observed after this single low-dose rituximab treatment.ConclusionsWe confirmed the clinical efficacy of low-dose rituximab by B cell depletion in autoimmune nodopathy with anti-CNTN1 antibody. This rapid and long-lasting response suggests that low-dose rituximab is a promising option for anti-CNTN1 nodopathy.

Becker muscular dystrophy (BMD), an X-linked recessive disorder caused of mutation in the dystrophin gene, is characterized by progressive muscle degeneration and proximal muscle weakness. We generated a human induced pluripotent stem cell (hiPSC) line from the fibroblasts isolated from patient with BMD by non-integrating reprogramming methods. The iPSC line highly expresses pluripotency markers, displays the normal karyotype and is able to differentiate into the three germ layers in vitro. The iPSC line will be a useful tool to study the pathogenesis of BMD and for drug screening.

We have established the human induced pluripotent stem cell (hiPSC) line (INNDSUi001-A) from skin fibroblasts of a healthy 24-year-old female individual by using non-integrating reprogramming method. The resulted cells had typical features of embryonic stem cell as indicated by expression of specific pluripotency markers and had the capability of in vitro differentiation into the three germ layers. This iPSC line can be used as a healthy control for disease study.

Limb-girdle muscular dystrophy 2G (LGMD2G) is a subtype of limb-girdle muscular dystrophy. However, the disease’s mechanisms are still not fully understood, and no established therapeutic targets have been found. Using a morpholino-based knockdown approach, we established an LGMD2G zebrafish model. In this study, we found that the ROS level increased in LGMD2G zebrafish. The expression of the mitophagy-related protein BNIP3L, LC3A-II/LC3A-I, and LAMP1 were increased in LGMD2G zebrafish. The oxygen consumption rate and citrate synthase expression was significantly decreased. Thus, mitophagy was presumed to be involved in the LGMD2G to reduce ROS levels. Then, we administered vitamin C, coenzyme Q10, idebenone, metformin, or dexamethasone to rescue LGMD2G in zebrafish. Idebenone reduced the curly tail phenotype and ROS level. Also, it reduced BNIP3L expression in LGMD2G zebrafish models and improved their motor function. In conclusion, mitophagy might be involved in the LGMD2G, and idebenone ameliorated LGMD2G by downregulating ROS level.

Congenital muscular dystrophy with early rigid spine, also known as the rigid spine with muscular dystrophy type 1 (RSMD1), is caused by SEPN1 mutation. We investigated the clinical manifestations, pathological features, and genetic characteristics of 8 Chinese RSMD1 patients in order to improve diagnosis and management of the disease. Eight patients presented with delayed motor development, muscle weakness, hypotonia, and a myopathic face with high palatine arches. All patients could walk independently, though with poor running and jumping, and most had a rigid spine, lordosis, or scoliosis. The symptoms of respiratory involvement were present early, and upper respiratory tract infections and pneumonia often occurred. Five patients had severe pneumonia, pulmonary hypertension, and respiratory failure. Lung function tests showed variable restrictive ventilation dysfunction. Polysomnography suggested hypoxia and hypoventilation. The serum creatine kinase (CK) level was normal or mildly increased. Muscle biopsy indicated chronic myopathic changes and minicores. Muscle magnetic resonance imaging (MRI) showed diffuse fatty infiltration of the gluteus maximus and thigh muscle. SEPN1 gene analysis revealed 16 compound heterozygous variants, 81.3% of which are unreported, including 7 exon 1 variants. Our study expands the spectrum of clinical and genetic findings in RSMD1 to improve diagnosis, management, and standards of care. SEPN1 mutations in exon 1 are common and easily missed, and exon 1 should be carefully analyzed when RSMD1 is suspected, which will provide valuable genetic counseling for the family and useful information for future natural history studies and clinical trials.

Abstract Background Sodium oligomannate (GV-971), a marine-derived oligosaccharide, is a novel agent that may improve cognition in AD patients. Methods The 24-week multicenter, randomized, double-blind, placebo parallel controlled clinical trial was conducted in AD in China between 24 October 2011 and 10 July 2013. The study included a 4-week screening/washout period, followed by a 24-week treatment period. Patients were randomized in a 1:1:1 ratio to receive GV-971 900 mg, 600 mg, or placebo capsule in treatment period, respectively. The primary outcome was cognitive improvement as assessed by changes in Alzheimer’s Disease Assessment Scale-cognitive subscale 12-item (ADAS-cog12) scores from baseline to week 24. The secondary efficacy outcomes included CIBIC-Plus, ADCS-ADL, and NPI at 24 weeks after treatment compared with baseline. A subgroup study was assessment of the change in cerebral glucose metabolism by fluorodeoxyglucose positron emission tomography measurements. Results Comparing with the placebo group (n = 83, change − 1.45), the ADAS-cog12 score change in the GV-971 600-mg group (n = 76) was − 1.39 (p = 0.89) and the GV-971 900-mg group (n = 83) was − 2.58 (p = 0.30). The treatment responders according to CIBIC-Plus assessment were significantly higher in the GV-971 900-mg group than the placebo group (92.77% vs. 79.52%, p

Abstract Objective Given their diverse phenotypes, mitochondrial diseases (MDs) are often difficult to diagnose. Fibroblast growth factor 21 (FGF‐21) and growth differentiation factor 15 (GDF‐15) represent promising biomarkers for MD diagnosis. Herein we conducted a meta‐analysis to compare their diagnostic accuracy for MDs. Methods We comprehensively searched PubMed, EMBASE, MEDLINE, the Web of Science, and Cochrane Library up to 1 January 2020. Data were analyzed by two independent reviewers. We obtained the sensitivity and specificity, positive and negative likelihood ratios (LR+ and LR‐), diagnostic odds ratios (DORs) and summary receiver operating characteristic (SROC) curves of each diagnostic method. Results Eight randomized controlled trials (RCTs) including 1563 participants (five encompassing 718 FGF‐21 assessments; seven encompassing 845 participants for GDF‐15) were included. Pooled sensitivity, specificity, DOR and SROC of FGF‐21 were 0.71 (95% CI 0.53, 0.84), 0.88(95% CI 0.82, 0.93), 18 (95% CI 6, 54), 0.90 (95% CI 0.87, 0.92), respectively, which were lower than GDF‐15 values; 0.83 (95% CI 0.65, 0.92), 0.92 (95% CI 0.84, 0.96), 52 (95% CI 13, 205), 0.94 (95% CI 0.92, 0.96). Interpretation FGF‐21 and GDF‐15 showed acceptable sensitivity and high specificity. Of the biomarkers, GDF‐15 had the highest diagnostic accuracy.

Abstract Objective Mitochondrial diseases are a group of genetic diseases caused by mutations in mitochondrial DNA and nuclear DNA, among which, mutations in mitochondrial tRNA genes possessing prominent status. In most of the cases, however, the detailed molecular pathogenesis of these tRNA gene mutations remains unclear. Methods We performed the clinical emulation, muscle histochemistry, northern blotting analysis of tRNA levels, biochemical measurement of respiratory chain complex activities and mitochondrial respirations in muscle tissue and cybrid cells. Results We found a novel m.4349C>T mutation in mitochondrial tRNAGln gene in a patient present with encephalopathy, epilepsy, and deafness. We demonstrated molecular pathomechanisms of this mutation. This mutation firstly disturbed the translation machinery of mitochondrial tRNAGlnand impaired mitochondrial respiratory chain complex activities, followed by remarkable mitochondrial dysfunction and ROS production. Interpretation. This study illustrated the pathogenicity of a novel m.4349C>T mutation and provided a better understanding of the phenotype associated with mutations in mitochondrial tRNAGln gene.

Sengers syndrome (OMIM #212350) is a rare autosomal recessive disorder due to mutations in acylglycerol kinase (AGK) gene. We report two cases that were diagnosed clinically and confirmed genetically. Both infants had typical clinical features characterized by hypertrophic cardiomyopathy, bilateral cataracts, myopathy, and lactic acidosis, and heart failure was the most severe manifestation. Genetic testing of a boy revealed a homozygous pathogenic variant for Sengers syndrome in AGK (c.1131+2T>C) which was classified as likely pathogenic according to the ACMG guideline; besides, his skeletal muscle biopsy and transmission electron microscope presented obvious abnormity. One girl had compound heterozygous (c.409C>T and c.390G>A) variants of AGK gene that was identified in the proband and further Sanger sequencing indicated that the parents carried a single heterozygous mutation each. After the administration of “cocktail” therapy including coenzyme Q10, carnitine, and vitamin B complex, as well as ACEI, heart failure and myopathy of the boy were significantly improved and the condition was stable after 1-year follow-up, while the cardiomyopathy of the girl is not progressive but the plasma lactate acid increased significantly. We present the first report of two infants with Sengers syndrome diagnosed via exome sequencing in China.

Abstract Background Neutral lipid storage disease with myopathy (NLSDM) is a rare clinical heterogeneous disorder caused by mutations in the patatin-like phospholipase domain-containing 2 (PNPLA2) gene. NLSDM usually presents skeletal myopathy, cardiomyopathy and the multiple organs dysfunction. Around 50 cases of NLSDM have been described worldwide, whereas the comprehensive understanding of this disease are still limited. We therefore recruit NLSDM patients from 10 centers across China, summarize the clinical, muscle imaging, pathological and genetic features, and analyze the genotype-phenotype relationship. Results A total of 45 NLSDM patients (18 men and 27 women) were recruited from 40 unrelated families. Thirteen patients were born from consanguineous parents. The phenotypes were classified as asymptomatic hyperCKemia (2/45), pure skeletal myopathy (18/45), pure cardiomyopathy (4/45), and the combination of skeletal myopathy and cardiomyopathy (21/45). Right upper limb weakness was the early and prominent feature in 61.5% of patients. On muscle MRI, the long head of the biceps femoris, semimembranosus and adductor magnus on thighs, the soleus and medial head of the gastrocnemius on lower legs showed the most severe fatty infiltration. Thirty-three families were carrying homozygous mutations, while seven families were carrying compound heterozygous mutations. A total of 23 mutations were identified including 11 (47.8%) point mutations, eight (34.8%) deletions and four (17.4%) insertions. c.757 + 1G > T, c.245G > A and c.187 + 1G > A were the three most frequent mutations. Among four groups of phenotypes, significant differences were shown in disease onset (

Abstract Background Pompe disease is a rare, progressive, autosomal recessive lysosomal storage disorder caused by mutations in the acid α-glucosidase gene. This is the first report of Chinese patients from the global Pompe Registry. Chinese patients enrolled in the Registry (ClinicalTrials.gov, NCT00231400) between Jan 2013 and 2 Sep 2016 with late onset Pompe disease (LOPD; presentation after 12 months of age or presentation at ≤12 months without cardiomyopathy) were included. Data analyses were descriptive. Results Of the 59 Chinese patients included, 86.4% had never received enzyme replacement therapy (ERT). The age at symptom onset and diagnosis was 14.9 (12.35) and 22.1 (10.08) years, which is younger than previous reports of LOPD patients from the rest of the world (28.4 [18.86] and 34.9 [20.03], respectively). The most common diagnosis methods were enzyme assay (79.7%) and/or DNA analysis (61.0%). Of the 36 patients diagnosed using DNA analysis, 31 had standardized variant data and among these patients the most common mutations were c.2238G > C (n = 18, 58.1%) and c.2662G > T (n = 5, 16.1%). Chinese LOPD patients appeared to have worse lung function versus patients from the rest of the world, indicated by lower forced vital capacity (37.2 [14.00]% vs. 63.5 [26.71]%) and maximal expiratory and inspiratory pressure (27.9 [13.54] vs. 51.0 [38.66] cm H2O, and 29.4 [12.04] vs. 70.5 [52.78] cm H2O). Conclusions Compared with patients from the rest of the world, Chinese patients with LOPD appeared to have younger age at symptom onset and diagnosis, lower lung function, and the majority had not received ERT. The most common mutations were c.2238G > C and c.2662G > T.

Neuroimaging studies of hippocampal volumes in patients with amyotrophic lateral sclerosis (ALS) have reported inconsistent results. Our aims were to demonstrate that such discrepancies are largely due to atrophy of different regions of the hippocampus that emerge in different disease stages of ALS and to explore the existence of co-pathology in ALS patients. We used the well-validated King’s clinical staging system for ALS to classify patients into different disease stages. We investigated in vivo hippocampal atrophy patterns across subfields and anterior-posterior segments in different King’s stages using structural MRI in 76 ALS patients and 94 health controls (HCs). The thalamus, corticostriatal tract and perforant path were used as structural controls to compare the sequence of alterations between these structures and the hippocampal subfields. Compared with HCs, ALS patients at King’s stage 1 had lower volumes in the bilateral posterior subiculum and presubiculum; ALS patients at King’s stage 2 exhibited lower volumes in the bilateral posterior subiculum, left anterior presubiculum and left global hippocampus; ALS patients at King’s stage 3 showed significantly lower volumes in the bilateral posterior subiculum, dentate gyrus and global hippocampus. Thalamic atrophy emerged at King’s stage 3. White matter tracts remained normal in a subset of ALS patients. Our study demonstrated that the pattern of hippocampal atrophy in ALS patients varies greatly across King’s stages. Future studies in ALS patients that focus on the hippocampus may help to further clarify possible co-pathologies in ALS.

Background To determine the efficacy of low-dose, immediate-release tacrolimus in patients with myasthenia gravis (MG) with inadequate response to glucocorticoid therapy in a randomized, double-blind, placebo-controlled study. Methods Eligible patients had inadequate response to glucocorticoids (GCs) after ⩾6 weeks of treatment with prednisone ⩾0.75 mg/kg/day or 60–100 mg/day. Patients were randomized to receive 3 mg tacrolimus or placebo daily (orally) for 24 weeks. Concomitant glucocorticoids and pyridostigmine were allowed. Patients continued GC therapy from weeks 1–4; from week 5, the dose was decreased at the discretion of the investigator. The primary efficacy outcome measure was a reduction, relative to baseline, in quantitative myasthenia gravis (QMG) score assessed using a generalized linear model; supportive analyses used alternative models. Results Of 138 patients screened, 83 [tacrolimus ( n = 45); placebo ( n = 38)] were enrolled and treated. The change in adjusted mean QMG score from baseline to week 24 was −4.9 for tacrolimus and −3.3 for placebo (least squares mean difference: –1.7, 95% confidence interval: −3.5, −0.1; p = 0.067). A post-hoc analysis demonstrated a statistically significant difference for QMG score reduction of ⩾4 points in the tacrolimus group (68.2%) versus the placebo group (44.7%; p = 0.044). Adverse event profiles were similar between treatment groups. Conclusions Tacrolimus 3 mg treatment for patients with MG and inadequate response to GCs did not demonstrate a statistically significant improvement in the primary endpoint versus placebo over 24 weeks; however, a post-hoc analysis demonstrated a statistically significant difference for QMG score reduction of ⩾4 points in the tacrolimus group versus the placebo group. This study was limited by the low number of patients, the absence of testing for acetylcholine receptor antibody and the absence of stratification by disease duration (which led to a disparity between the two groups). ClinicalTrials.gov identifier: NCT01325571

Although intracellular beta amyloid (Aβ) accumulation is known as an early upstream event in the degenerative course of UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) myopathy, the process by which Aβdeposits initiate various degradative pathways, and their relationship have not been fully clarified. We studied the possible secondary responses after amyloid beta precursor protein (AβPP) deposition including unfolded protein response (UPR), ubiquitin proteasome system (UPS) activation and its correlation with autophagy system. Eight GNE myopathy patients and five individuals with normal muscle morphology were included in this study. We performed immunofluorescence and immunoblotting to investigate the expression of AβPP, phosphorylated tau (p-tau) and endoplasmic reticulum molecular chaperones. Proteasome activities were measured by cleavage of fluorogenic substrates. The expression of proteasome subunits and linkers between proteasomal and autophagy systems were also evaluated by immunoblotting and relative quantitative real-time RT-PCR. Four molecular chaperones, glucose-regulated protein 94 (GRP94), glucose-regulated protein 78 (GRP78), calreticulin and calnexin and valosin containing protein (VCP) were highly expressed in GNE myopathy. 20S proteasome subunits, three main proteasome proteolytic activities, and the factors linking UPS and autophagy system were also increased. Our study suggests that AβPP deposition results in endoplasmic reticulum stress (ERS) and highly expressed VCP deliver unfolded proteins from endoplasmic reticulum to proteosomal system which is activated in endoplasmic reticulum associated degradation (ERAD) in GNE myopathy. Excessive ubiquitinated unfolded proteins are exported by proteins that connect UPS and autophagy to autophagy system, which is activated as an alternative pathway for degradation.

Background Oculopharyngodistal myopathy (OPDM) is a rare adult-onset neuromuscular disease, associated with CGG repeat expansions in the 5' untranslated region of LRP12, GIPC1, NOTCH2NLC and RILPL1. However, the genetic cause of a proportion of pathoclinically confirmed cases remains unknown. Methods A total of 26 OPDM patients with unknown genetic cause(s) from 4 tertiary referral hospitals were included in this study. Clinical data and laboratory findings were collected. Muscle samples were observed by histological and immunofluorescent staining. Long-read sequencing was initially conducted in six patients with OPDM. Repeat-primed PCR was used to screen the CGG repeat expansions in LOC642361/NUTM2B-AS1 in all 26 patients. Results We identified CGG repeat expansion in the non-coding transcripts of LOC642361/NUTM2B-AS1 in another two unrelated Chinese cases with typical pathoclinical features of OPDM. The repeat expansion was more than 70 times in the patients but less than 40 times in the normal controls. Both patients showed no leucoencephalopathy but one showed mild cognitive impairment detected by Montreal Cognitive Assessment. Rimmed vacuoles and p62-positive intranuclear inclusions (INIs) were identified in muscle pathology, and colocalisation of CGG RNA foci with p62 was also found in the INIs of patient-derived fibroblasts. Conclusions We identified another two unrelated cases with CGG repeat expansion in the long non-coding RNA of the LOC642361/NUTM2B-AS1 gene, presenting with a phenotype of OPDM. Our cases broadened the recognised phenotypic spectrum and pathogenesis in the disease associated with CGG repeat expansion in LOC642361/NUTM2B-AS1. [ABSTRACT FROM AUTHOR]

Background Mutations in the tropomyosin receptor kinase fused (TFG) gene are associated with various neurological disorders, including autosomal recessive hereditary spastic paraplegia (HSP), autosomal dominant hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) and autosomal dominant type of Charcot-Marie-Tooth disease type 2. Methods Whole genome sequencing and whole-exome sequencing were used, followed by Sanger sequencing for validation. Haplotype analysis was performed to confirm the inheritance mode of the novel TFG mutation in a large Chinese family with HSP. Additionally, another family diagnosed with HMSN-P and carrying the reported TFG mutation was studied. Clinical data and muscle pathology comparisons were drawn between patients with HSP and patients with HMSN-P. Furthermore, functional studies using skin fibroblasts derived from patients with HSP and patients with HMSN-P were conducted to investigate the pathomechanisms of TFG mutations. Results A novel heterozygous TFG variant (NM_006070.6: c.125G>A (p.R42Q)) was identified and caused pure HSP. We further confirmed that the well-documented recessively inherited spastic paraplegia, caused by homozygous TFG mutations, exists in a dominantly inherited form. Although the clinical features and muscle pathology between patients with HSP and patients with HMSN-P were distinct, skin fibroblasts derived from both patient groups exhibited reduced levels of autophagy-related proteins and the presence of TFG-positive puncta. Conclusions Our findings suggest that autophagy impairment may serve as a common pathomechanism among different clinical phenotypes caused by TFG mutations. Consequently, targeting autophagy may facilitate the development of a uniform treatment for TFG-related neurological disorders. [ABSTRACT FROM AUTHOR]