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Suppressor of Mek1 (Smek1) is a regulatory subunit of protein phosphatase 4. Genome-wide association studies have shown the protective effect of SMEK1 in Alzheimer's disease (AD). However, the physiological and pathological roles of Smek1 in AD and other tauopathies are largely unclear. Here, the role of Smek1 in preventing neurodegeneration is investigated in tauopathy. Smek1 is downregulated in the aged human brain. Through single-cell sequencing, a novel neuronal cluster is identified that possesses neurodegenerative characteristics in Smek1 -/- mice. Smek1 deficiency caused markedly more severe motor and cognitive impairments in mice, as well as neuronal loss, gliosis, and tau hyperphosphorylation at major glycogen synthase kinase 3β (Gsk3β) sites. Protein-protein interaction analysis revealed that the Ran-binding domain (RanBD) in the N-terminus of Smek1 facilitated binding with kinesin family member 2A (Kif2a). Depletion of Smek1 resulted in cytoplasmic aggregation of Kif2a, axon outgrowth defects, and impaired mitochondrial axonal trafficking. Downregulation of Kif2a markedly attenuated tau hyperphosphorylation and axon outgrowth defects in shSmek1 cells. For the first time, this study demonstrates that Smek1 deficiency progressively induces neurodegeneration by exacerbating tau pathology and mitochondrial dysfunction in an age-dependent manner., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Blood vessels constitute a closed pipe system distributed throughout the body, transporting blood from the heart to other organs and delivering metabolic waste products back to the lungs and kidneys. Changes in blood vessels are related to many disorders like stroke, myocardial infarction, aneurysm, and diabetes, which are important causes of death worldwide. Translational research for new approaches to disease modeling and effective treatment is needed due to the huge socio-economic burden on healthcare systems. Although mice or rats have been widely used, applying data from animal studies to human-specific vascular physiology and pathology is difficult. The rise of induced pluripotent stem cells (iPSCs) provides a reliable in vitro resource for disease modeling, regenerative medicine, and drug discovery because they carry all human genetic information and have the ability to directionally differentiate into any type of human cells. This review summarizes the latest progress from the establishment of iPSCs, the strategies for differentiating iPSCs into vascular cells, and the in vivo transplantation of these vascular derivatives. It also introduces the application of these technologies in disease modeling, drug screening, and regenerative medicine. Additionally, the application of high-tech tools, such as omics analysis and high-throughput sequencing, in this field is reviewed., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

The clinical and molecular genetic data of 6 patients with genetically confirmed tyrosine hydroxylase deficiency(THD) diagnosed in Department of Neurology, Qilu Hospital of Shandong University from March 2017 to February 2022 were retrospectively collected and analyzed. The 6 patients were from 5 families. Among them, 5 patients had persistent or paroxysmal abnormal walking posture, 4 patients had dystonia of head and face, including spasm of perioral and oculopharyngeal muscles, hyperactivity, and binocular upvision, 4 patients showed obvious morning light and evening heavy phenomenon, 2 patients had postural tremor of limbs, 2 patients had psychomotor retardation from childhood, 1 patient only had limb and cervical muscle weakness, 1 patient had epileptic seizures. Of the 6 patients, only 1 was adult-onset, and the rest were child-onset. Four patients had good response to low-dose dopa preparation, 2 patients from the same family had poor response to dopamine treatment, requiring extremely low dose initiation and multi-frequency titration treatment. However, the long-term treatment effect was poor with obvious abnormalities. Gene testing of 5 families revealed 8 mutations in the TH gene, with c.698G>A (p.R233H) being the hot spot mutation site. The clinical manifestations of THD are complex. Besides paroxysmal or persistent dystonia, it can also be accompanied by eye movement crisis, muscle weakness, epilepsy, and delayed mental and motor development. Most patients respond well to low-dose dopamine preparations, but a small number of patients require titration treatment with extremely low-dose dopamine preparations, and the long-term effect is not satisfactory.

Brain calcification is a critical aging-associated pathology and can cause multifaceted neurological symptoms. Cerebral phosphate homeostasis dysregulation, blood-brain barrier defects, and immune dysregulation have been implicated as major pathological processes in familial brain calcification (FBC). Here, we analyzed two brain calcification families and identified calcification co-segregated biallelic variants in the CMPK2 gene that disrupt mitochondrial functions. Transcriptome analysis of peripheral blood mononuclear cells (PBMCs) isolated from these patients showed impaired mitochondria-associated metabolism pathways. In situ hybridization and single-cell RNA sequencing revealed robust Cmpk2 expression in neurons and vascular endothelial cells (vECs), two cell types with high energy expenditure in the brain. The neurons in Cmpk2-knockout (KO) mice have fewer mitochondrial DNA copies, down-regulated mitochondrial proteins, reduced ATP production, and elevated intracellular inorganic phosphate (Pi) level, recapitulating the mitochondrial dysfunction observed in the PBMCs isolated from the FBC patients. Morphologically, the cristae architecture of the Cmpk2-KO murine neurons was also impaired. Notably, calcification developed in a progressive manner in the homozygous Cmpk2-KO mice thalamus region as well as in the Cmpk2-knock-in mice bearing the patient mutation, thus phenocopying the calcification pathology observed in the patients. Together, our study identifies biallelic variants of CMPK2 as novel genetic factors for FBC; and demonstrates how CMPK2 deficiency alters mitochondrial structures and functions, thereby highlighting the mitochondria dysregulation as a critical pathogenic mechanism underlying brain calcification., (© 2022. The Author(s).)

The pollution of micro/nanoplastics in the natural environment is becoming increasingly serious, but the potential effects of nanoplastics on crops remain unclear. In the present study, the effects of polystyrene nanoplastics (PS-NPs) with a particle size of 80 nm on the chlorophyll content, antioxidant enzyme activity, and nutritional quality of Allium sativum L. were explored via hydroponic culture. The results showed that the chlorophyll contents in leaves of A. sativum treated with PS-NPs were significantly lower than those in the control, indicating that the synthesis of chlorophyll was inhibited. The superoxide dismutase (SOD), ascorbate peroxidase (APX) activities, and proline contents in leaves of A. sativum initially increased but then decreased with the increase in ρ (PS-NPs). The activity of guaiacol peroxidase (POD) increased with the increase in ρ (PS-NPs) for 10 days of treatment; however, it was inhibited for 20 days of treatment. The malondialdehyde (MDA) content increased with the rise in ρ (PS-NPs). When ρ (PS-NPs) increased to 100 mg·L -1 , the MDA content in leaves of A. sativum increased by 43.24% and 89.70% for 10 and 20-day treatments, respectively, compared with those in the control. Meanwhile, the contents of soluble protein, soluble sugar, and vitamin C were higher than those in the control for 10-day treatments; however, the vitamin C content decreased by 26.53% after 20 days of treatment. These results indicated that PS-NPs had a significant oxidative stress on A. sativum , and a high concentration of PS-NPs stress would have deleterious effects on the nutritional quality of A. sativum .

Objective: This study aims to establish an optimization procedure to define the cut-offs of quantitative assays for acetylcholine receptor antibody (AChRAb), evaluate their diagnostic performance in myasthenia gravis (MG), and explore the association with clinical features., Methods: Samples from a representative cohort of 77 MG patients, 80 healthy controls (HC) and 80 other autoimmune diseases (OAD) patients were tested using competitive inhibition ELISA and RIA. Raw values (OD and cpm) and processed values (inhibition rate, binding rate and concentration) were used to define the cut-offs with statistical methods, a rough method, and receiver operating characteristic (ROC) curve. Optimal cut-offs were selected by comparing false positive rates in HC and OAD individuals. The diagnostic performance was evaluated in whole MG cohort and subgroups. Agreement between ELISA and RIA for AChRAb positivity were examined with Kappa test and McNemar test. Clinical association with AChRAb was explored by comparison among subgroups and with Spearman rank correlation., Results: The optimal cut-offs for AChRAb positivity were determined as OD ≤ 1.79 for ELISA and cpm ≥ 1234.12 for RIA, which derived from statistical method and performed better than those derived from ROC curves. The sensitivity and specificity were 74.03%, 100% for ELISA, and 74.03%, 99.37% for RIA. There was good agreement between ELISA and RIA for AChRAb positivity in whole cohort and subgroups (weighted к ≥ 0.71, p < 0.01; McNemar test, p > 0.05). Levels of AChRAb were different in MG subgroups (p < 0.01). Correlation between Quantitative Myasthenia Gravis scores and AChRAb levels was moderate for ELISA and RIA (r s  = -0.60 and 0.57, p < 0.01)., Conclusion: The raw testing values of ELISA and RIA were found as optimal quantitative measures of AChRAb levels. There are good agreements on diagnostic performance between two assays. Quantitative values are more informative than positivity in association with clinical features., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: GNE myopathy is the most common distal myopathy in China. We summarized the clinical, genetic, and pathological characteristics of 125 Chinese patients with GNE myopathy., Methods: We collected clinical data of 21 patients diagnosed at our hospital and 104 patients from previous reports. Clinical, genetic, and pathological characteristics were summarized. According to the location of mutations, patients were classified into groups to analyze genotype-phenotype correlation. We reviewed the pathological features and studied the expressions of neural cell adhesion molecule., Results: The severity of involvement of lower limb muscles was in the following order: tibialis anterior > biceps femoris > gastrocnemius > iliopsoas > quadriceps femoris. Mutation p.D207V was the most common variant in China. Patients carrying p.D207V tended to show later disease onset. In the epimerase/epimerase group, men had earlier disease onset than women (p < 0.05). In other groups, age at disease onset in females was earlier than that in males. Protein analysis showed decreased sialylation of NCAM and upregulation of LC3 in patients with different mutations., Conclusions: Mutation p.D207V is the most common GNE variant in China. Involvement of flexor muscles in lower limbs was more obvious than extensor muscles. NCAM expression in patients with various mutations may be a useful diagnostic biomarker in GNE myopathy., (© 2022. Fondazione Società Italiana di Neurologia.)

Background and Purpose: Breast cancer (BRCA) is the most frequent female malignancy and is potentially life threatening. The amino acid metabolism (AAM) has been shown to be strongly associated with the development and progression of human malignancies. In turn, long noncoding RNAs (lncRNAs) exert an important influence on the regulation of metabolism. Therefore, we attempted to build an AAM-related lncRNA prognostic model for BRCA and illustrate its immune characteristics and molecular mechanism. Experimental Design: The RNA-seq data for BRCA from the TCGA-BRCA datasets were stochastically split into training and validation cohorts at a 3:1 ratio, to construct and validate the model, respectively. The amino acid metabolism-related genes were obtained from the Molecular Signature Database. A univariate Cox analysis, least absolute shrinkage and selection operator (LASSO) regression, and a multivariate Cox analysis were applied to create a predictive risk signature. Subsequently, the immune and molecular characteristics and the benefits of chemotherapeutic drugs in the high-risk and low-risk subgroups were examined. Results: The prognostic model was developed based on the lncRNA group including LIPE-AS1, AC124067.4, LINC01655, AP005131.3, AC015802.3, USP30-AS1, SNHG26, and AL589765.4. Low-risk patients had a more favorable overall survival than did high-risk patients, in accordance with the results obtained for the validation cohort and the complete TCGA cohort. The elaborate results illustrated that a low-risk index was correlated with DNA-repair-associated pathways; a low TP53 and PIK3CA mutation rate; high infiltration of CD4 + T cells, CD8 + T cells, and M1 macrophages; active immunity; and less-aggressive phenotypes. In contrast, a high-risk index was correlated with cancer and metastasis-related pathways; a high PIK3CA and TP53 mutation rate; high infiltration of M0 macrophages, fibroblasts, and M2 macrophages; inhibition of the immune response; and more invasive phenotypes. Conclusion: In conclusion, we attempted to shed light on the importance of AAM-associated lncRNAs in BRCA. The prognostic model built here might be acknowledged as an indispensable reference for predicting the outcome of patients with BRCA and help identify immune and molecular characteristics., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Dai, Wen, Wu, Wu, Lv, Yan, Liu, Wang and Zheng.)

Tumor microenvironment (TME) regulated the development of the Lung squamous cell carcinoma (LUSC). To know more about the LUSC, this study tried to figure the role of fscin actin-bundling protein 1 (FSCN1) in the TME. We identified the FSCN1 as the hub immune gene in LUSC, with the use of weighted gene co-expression network analysis (WGCNA) and the Human Protein Atlas. Furthermore, we verified the higher expression of FSCN1 in LUSC compared with the normal tissues by quantitative reverse transcription PCR (qRT-PCR) and immunohistochemistry. We then explored the associations among FSCN1, immune infiltrations, and inflammatory factors with the use of Gene Expression Profiling Interactive Analysis (GEPIA) and Tumor IMmune Estimation Resource (TIMER). As a result, the expressions of FSCN1 was negatively related to the immune infiltrations, and positively related to the expressions of IL1A, IL1B, TGFB1 and TGFA. Moreover, we used the single-cell RNA-sequencing (scRNA-seq) data of LUSC to figure out the expressions level of FSCN1, IL1A, IL1B, TGFB1 and TGFA in the different cell type's of the TME. Finally, through the cytological experiments, we found that FSCN1 affected by TGFB1 contributes to the proliferation, anti-apoptotic effect, migration and invasion of the LUSC cells. In summary, this study Identified FSCN1 as the potential therapeutic target of LUSC, and reveals a complicated immune and inflammatory net in the TME., (Copyright © 2022 Elsevier GmbH. All rights reserved.)