A novel variant of biallelic MME gene associated with autosomal recessive late-onset distal hereditary motor neuropathy in Chinese families.

Distal hereditary motor neuropathies (dHMN) are a group of heterogeneous diseases and previous studies have reported that the compound heterozygous recessive MME variants cause dHMN. Our study found a novel homozygous MME variant and a reported compound heterozygous MME variant in two Chinese families, respectively. Next-generation sequencing and nerve conduction studies were performed for two probands. The probands in two families presented with the muscle weakness and wasting of both lower limbs and carried a c.2122 A > T (p.K708*) and c.1342 C > T&c.2071_2072delinsTT (p.R448*&p.A691L) variant, respectively. Prominently axonal impairment of motor nerves and slight involvement of sensory nerves were observed in nerve conduction study. Our study reported a "novel" nonsense mutation and a missense variant of autosomal recessive late-onset dHMN and reviewed reported MME variants associated with dHMN phenotype.

The clinical and genetic spectrum of mitochondrial diseases in China: A multicenter retrospective cross-sectional study.

Mitochondrial diseases (MtDs) present diverse clinical phenotypes, yet large-scale studies are hindered by their rarity. This retrospective, multicenter study, conducted across five Chinese hospitals' neurology departments from 2009 to 2019, aimed to address this gap. Nationwide, 1351 patients were enrolled, with a median onset age of 14.0 (18.5) years. The predominant phenotype was mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) (45.0%). Mitochondrial DNA (mtDNA) mutations were prevalent (87.4%), with m.3243A>G being the most common locus (48.7%). Meanwhile, POLG mutations in nuclear DNA (nDNA) accounted for 16.5%. Comparative analysis based on age groups (with a cut-off at 14 years) revealed the highest prevalence of MELAS, with Leigh syndrome (LS) and chronic progressive external ophthalmoplegia (CPEO) being the second most common phenotypes in junior and senior groups, respectively. Notably, the most commonly mutated nuclear genes varied across age groups. In conclusion, MELAS predominated in this Chinese MtD cohort, underscored by m.3243A>G and POLG as principal mtDNA mutations and pathogenic nuclear genes. The phenotypic and genotypic disparities observed among different age cohorts highlight the complex nature of MtDs.

Circulating Cell-Free DNA Promotes Inflammation in Patients with Dermatomyositis with Anti-NXP2 Antibodies via the cGAS/STING Pathway.

OBJECTIVES: Dermatomyositis (DM) is a rare type I interferon (IFN-I)-driven autoimmune disease, and anti-nuclear matrix protein 2 (NXP2) antibody is related to severe muscle disease and poor prognosis. Circulating cell-free DNA (ccf-DNA), including ccf-mitochondrial DNA and ccf-nuclear DNA, activates cGAS/STING pathway to induce IFN-I production in autoimmune diseases. We investigated whether serum-derived ccf-DNA played a pathogenic role on skeletal muscle in anti-NXP2 antibody-positive DM. METHODS: Serum ccf-DNA levels were measured, and correlations between ccf-DNA and clinicopathological indicators were performed. RNA sequencing, immunofluorescence, western blotting and RT-qPCR were performed on skeletal muscle samples. The serum-induced expression of p-STING in C2C12 cells was assessed in vitro. RESULTS: We found that increased ccf-DNA levels were positively correlated with MYOACT scores in anti-NXP2 antibody-positive DM. RNA sequencing and immunofluorescence results revealed that the cytosolic DNA-sensing pathway was upregulated and that increased cytosolic dsDNA was colocalised with cGAS in skeletal muscle in anti-NXP2 antibody-positive DM. Western blot analysis revealed activation of the cGAS/STING pathway in patients with perifascicular atrophy (PFA) but not in patients without PFA. RT-qPCR showed increased IFN-I scores in both patients with PFA and patients without PFA. Sera from patients with PFA increased p-STING expression in C2C12 cells, and DNase I treatment and STING inhibitor efficiently inhibited p-STING expression, respectively. CONCLUSIONS: Increased ccf-DNA levels may be potential biomarkers for monitoring disease activity in anti-NXP2 antibody-positive DM. Activation of the cGAS/STING pathway is associated with PFA. Our findings identify the pathogenic role of ccf-DNA on skeletal muscle via the cGAS/STING pathway.

Spinal histamine H4 receptor mediates chronic pruritus via p-ERK in acetone-ether-water (AEW)-induced dry skin mice.

Dry skin is common to many pruritic diseases and is difficult to improve with oral traditional antihistamines. Recently, increasing evidence indicated that histamine H4 receptor (H4R) plays an important role in the occurrence and development of pruritus. Extracellular signal-regulated kinase (ERK) phosphorylation activation in the spinal cord mediates histamine-induced acute and choric itch. However, whether the histamine H4 receptor regulates ERK activation in the dry skin itch remains unclear. In the study, we explore the role of the histamine H4 receptor and p-ERK in the spinal cord in a dry skin mouse model induced by acetone-ether-water (AEW). q-PCR, Western blot, pharmacology and immunofluorescence  were applied in the study. We established a dry skin itch model by repeated application of AEW on the nape of neck in mice. The AEW mice showed typically dry skin histological change and persistent spontaneous scratching behaviour. Histamine H4 receptor, instead of histamine H1 receptor, mediated spontaneous scratching behaviour in AEW mice. Moreover, c-Fos and p-ERK expression in the spinal cord neurons were increased and co-labelled with GRPR-positive neurons in AEW mice. Furthermore, H4R agonist 4-methyhistamine dihydrochloride (4-MH)induced itch. Both 4-MH-induced itch and the spontaneous itch in AEW mice were blocked by p-ERK inhibitor U0126. Finally, intrathecal H4R receptor antagonist JNJ7777120 inhibited spinal p-ERK expression in AEW mice. Our results indicated that spinal H4R mediates itch via ERK activation in the AEW-induced dry skin mice.

CS/PVP Hydrogel-Based Nanocapillary for Monitoring Bacterial Growth and Rapid Antibiotic Susceptibility Testing.

Infection with drug-resistant bacteria poses a significant threat to human health. Judicious use of antibiotics could reduce the likelihood of bacterial resistance, which can be evaluated through antibiotic susceptibility testing (AST). This paper focuses on the application of a needle-like nanocapillary tip filled with chitosan (CS)/polyethylene pyrrolidone (PVP) hydrogel based on its specific pH-sensitive properties. The gel-filled nanocapillary has the potential to be used for electrical pH detection with a sensitivity of 3.06 nA/pH and a linear range from 7.3 to 4.3. Such sensitivity for pH measurement could be extended for monitoring of bacterial (such as Escherichia coli and Streptococcus salivarius) growth because of the relationship between pH and bacterial growth. Bacterial growth curves obtained using the hydrogel-filled nanocapillary showed good agreement with the OD600 method. Moreover, this device could be applied for rapid AST for tetracycline and norfloxacin on E. coli with minimum inhibitory concentrations of 2 and 0.125 µg/mL, respectively. This study expands the application of the hydrogel-based nanocapillary for bacterial research by monitoring changes in pH values.

[Treatment of Tile type C pelvic ring fracture using orthopedic robot combined with Starr pelvis reduction frame].

OBJECTIVE: To investigate the clinical effect of orthopedic robot combined with Starr pelvic reduction frame in the treatment of Tile type C pelvic ring fracture. METHODS: From October 2019 to May 2021, 14 patients with type C pelvic ring fracture were treated with robotic combined with Starr pelvic reduction frame, including 9 males and 5 females. The age ranged from 33 to 69 years. All the 14 patients had fresh closed fractures without femur, tibia and fibula fracture. Surgery was completed from 4 to 7 d after hospital admission. During the operation, the X-ray carbon bed was used, the pelvic ring was reduced by Starr pelvis reduction frame, and pelvic ring fracture was treated by orthopedic robot. Operation time, bleeding volume, fluoroscopy times of single screw placement, fracture reduction quality, affected limb function and complications were observed. Radiological reduction was evaluated using Matta scoring standard, and clinical efficacy was evaluated by Majeed pelvic function scoring system at the final follow-up. RESULTS: All of 14 patients successfully completed the operation, the operation time was 84 to 141 min, the bleeding volume was 20 to 50 ml, and the fluoroscopy times of single screw insertion was 4 to 9 times. All of 14 patients were followed up for 12 to 24 months. The healing time was 3 to 7 months. No complications such as fracture of internal fixation, screw loosening, infection and nerve injury were found. According to the evaluation criteria of Matta imaging reduction, 9 cases were excellent, 4 cases were good, and 1 case was fair. At the final follow-up, Majeed pelvic function scoring system was used:10 cases were excellent, 4 cases were good. CONCLUSION: The treatment of type C pelvic ring fracture with robotic combined Starr pelvis reduction frame is simple, time-saving, less trauma, less complications and effective.

[Mechanism of Huangjing Qianshi Decoction in treatment of prediabetic mice based on transcriptome sequencing].

Based on transcriptome sequencing technology, the mouse model of prediabetes treated with Huangjing Qianshi Decoction was sequenced to explore the possible mechanism of treating prediabetes. First of all, transcriptome sequencing was performed on the normal BKS-DB mouse group, the prediabetic model group, and the Huangjing Qianshi Decoction treatment group(treatment group) to obtain differentially expressed genes in the skeletal muscle samples of mice. The serum biochemical indexes were detected in each group to screen out the core genes of Huangjing Qianshi Decoction in prediabetes. Gene Ontology(GO) database and Kyoto Encyclopedia of Genes and Genomes(KEGG) database were used to conduct signaling pathway enrichment analysis of differentially expressed genes, and real-time quantitative polymerase chain reaction(RT-qPCR) was used to verify them. The results showed that the levels of fasting blood glucose(FBG), fasting insulin(FINS), insulin resistance index(HOMA-IR), total cholesterol(TC), triglycerides(TG), and low-density lipoprotein cholesterol(LDL-C) in the mouse model were significantly decreased after treatment with Huangjing Qianshi Decoction. In the results of differential gene screening, there were 1 666 differentially expressed genes in the model group as compared with the normal group, and there were 971 differentially expressed genes in the treatment group as compared with the model group. Among them, interleukin-6(IL-6) and NR3C2 genes, which were closely related to the regulation of insulin resis-tance function, were significantly up-regulated between the model group and the normal group, and vascular endothelial growth factor A(VEGFA) genes were significantly down-regulated between the model group and the normal group. However, the expression results of IL-6, NR3C2, and VEGFA genes were adverse between the treatment group and the model group. GO functional enrichment analysis found that the biological process annotation mainly focused on cell synthesis, cycle, and metabolism; cell component annotation mainly focused on organelles and internal components; and molecular function annotation mainly focused on binding molecular functions. KEGG pathway enrichment analysis found that it involved the protein tyrosine kinase 6(PTK6) pathway, CD28-dependent phosphoinositide 3-kinase/protein kinase B(PI3K/AKT) pathway, p53 pathway, etc. Therefore, Huangjing Qianshi Decoction can improve the state of prediabetes, and the mechanism may be related to cell cycle and apoptosis, PI3K/AKT pathway, p53 pathway, and other biological pathways regulated by IL-6, NR3C2, and VEGFA.

Novel variants, muscle imaging, and myopathological changes in Chinese patients with VCP-related multisystem proteinopathy.

OBJECTIVE: The objective of this research was to study the clinical features, genetic characteristics, muscle imaging, and muscle pathological changes of a cohort of Chinese patients with mutations in the valosin-containing protein (VCP) gene. METHODS: Nine patients from seven Chinese pedigrees were recruited. Variants were detected by next-generation sequencing and confirmed by Sanger sequencing. Thigh muscle MRIs were performed in five patients. All the patients received muscle biopsies. RESULTS: Seven variants in VCP were identified, and two were novel. All the patients presented with adult-onset muscle weakness. The appearance of "isolated island sign" or "contra-isolated island sign" was observed in four of the five the patients on muscle MRIs. Muscle biopsies demonstrated the combination of neuropathic and myopathic changes in seven patients and muscle dystrophic changes in two patients. Notably, rimmed vacuoles and cytoplasmic VCP and p62-positive protein aggregates were observed in all the patients. CONCLUSION: Our finding of novel variants expanded the mutational spectrum of the VCP gene. This cohort of Chinese patients with VCP mutations mainly present with inclusion body myopathy with predominant limb-girdle distribution. The characteristic pattern of fatty infiltration, especially the "isolated island" and "contra-isolated island" on muscle MRI, along with rimmed vacuoles in muscle biopsy, provides valuable clues for guiding genetic diagnostic workup.

Meroterpenoids with Immunosuppressive Activity from Edible Fungus Craterellus odoratus.

Two unusual polyketide-sesquiterpene metabolites, craterodoratins T (1) and U (2), along with the known compound craterellin A (3), were isolated from the higher fungus Craterellus odoratus. The structures of isolated compounds were characterized based on nuclear magnetic resonance (NMR) and mass spectrum (MS) spectroscopic analysis, while the absolute configuration of the compounds was determined by theoretical NMR and electronic circular dichroism (ECD) calculations. Compound 1 possessed a rare structure with two aromatic groups. Compounds 1 and 3 showed immunosuppressive activity with IC50 values ranging from 5.516 to 19.953 µM.

Lanostane triterpenoids from the fungus Physisporinus vitreus and their inhibitory activity against nitric oxide production.

Eight undescribed lanostane triterpenoids, physivitrins A-H, along with four known analogues, were isolated from cultures of the fungus Physisporinus vitreus. Their structures were elucidated on the basis of extensive spectroscopic methods, in which the absolute configuration of physivitrin A was elucidated using electronic circular dichroism calculation and nuclear magnetic resonance (NMR) calculation with DP4+ analysis. Physivitrins B and C showed inhibitory activities against nitric oxide (NO) production in LPS-activated RAW264.7 macrophages with IC50 values of 7.5 and 23.5 µM, respectively. Meanwhile, proinflammatory cytokines (TNF-α, iNOS and IL-1ß) mRNA expression was also inhibited by physivitrin B significantly.

Paenibacillus alkalitolerans sp. nov., a bacterium isolated from a salt lake of Turpan City in Xinjiang Province, north-west China.

A Gram stain-positive, rod-shaped, motile, aerobic and terminal endospore formation bacterium, designated YIM B00362T, was isolated from saline soil samples collected from a salt lake in Xinjiang Province, north-west China. Phylogenetic analysis based on the 16S rRNA gene sequences and whole genomes indicated that the isolate belongs to the genus Paenibacillus. However, the highest sequence similarity between strain YIM B00362T and the relatives was only 94.4%. Moreover, the DNA-DNA relatedness and ANI values between the novel isolate and the relative type strain, Paenibacillus antri SYSU K30003T was 13.6% and 70.3%, respectively. The major cellular fatty acids were anteiso-C15:0, C16:0 and the major quinone was MK-7. The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylglyceride, and two unidentified polar lipids. The genomic DNA G + C content was 50.9 mol%. The major whole-cell sugars contained glucose and galactose. On the basis of physiological, phenotypic, and chemotaxonomic data, strain YIM B00362T represents a novel species of genus Paenibacillus, for which the name Paenibacillus alkalitolerans sp. nov. is proposed. The type strain is YIM B00362T (= KCTC 43272 T = CGMCC 1.18801 T = NBRC 114667 T).

[Staged operation for complex closed Pilon fracture].

OBJECTIVE: To explore clinical efficacy of staged surgery in treating complex closed Pilon fracture. METHODS: From June 2019 to January 2021, 29 patients with complex closed Pilon fracture were treated by staging surgery, including 18 males and 11 females, aged ranged from 31 to 68 years old with an average of (43.50±6.62) years old;7 cases were typeⅡand 22 cases were type Ⅲ according to Ruedi-Allgower classification. All patients had fresh closed fractures without talus and calcaneal fractures. The time from injury to closed reduction and external fixation, the interval between two stages of surgery, fracture healing time and complications were recorded. American Orthopedic Foot and Ankle Society(AOFAS) was used to assess clinical effects. Burwell-Charnley system was used to evaluate radiological reduction. RESULTS: All 29 patients were followed up from 13 to 30 months with an aver age of (15.43±5.31) months. All fractures healed well from 2 to 6 months with an average of (3.77±1.22) months. No internal fixation fracture, screw loosening, infection, internal fixation irritation, ankle stiffness occurred. The time from injury to closed reduction and cross-ankle fixation ranged from 1.22 to 7.34 h with an average of(2.31±3.52) h, the interval between two stages ranged from 5 to 9 days with an average of (5.98±2.11) days. AOFAS score was improved from 34.11±6.89 before operation to 90.10±10.11 after oepration at 12 months(P<0.05). According to AOFAS grading, 16 patients got excellent result, 9 good and 4 moderate. Fifteen patients got anatomic reduction, 12 patients were good reduction, and 2 cases were poor reduction according to Burwell-Charnley system. CONCLUSION: Staged surgery for complex closed Pilon fracture has advantages of less complications, statisfied reduction, stable fixation, which could obtain good recovery of ankle joint.

Subsarcolemmal and cytoplasmic p62 positivity and rimmed vacuoles are distinctive for PLIN4-myopathy.

PLIN4-myopathy is a recently identified autosomal dominant muscular disorder caused by the coding 99 bp repeat expansion in PLIN4, presenting with distal or proximal weakness. Here, we report one family and one sporadic case of adult-onset PLIN4-associated limb-girdle weakness, whose diagnoses were achieved by a comprehensive genetic analysis workup. We provided additional evidence that the combination of subsarcolemmal/cytoplasmic ubiquitin/p62 positive deposits and rimmed vacuoles could serve as a strong indicator of PLIN4-myopathy. Moreover, we found novel myopathological features that were ultrastructural subsarcolemmal filamentous materials and membrane-bound granulofilamentous inclusions formed by the co-deposition of disrupted lipid droplets and p62 protein aggregates.

First Identification of Rare Exonic and Deep Intronic Splice-Altering Variants in Patients With Beta-Sarcoglycanopathy.

Background: The precise genetic diagnosis of a sarcoglycanopathy or dystrophinopathy is sometimes extremely challenging, as pathogenic non-coding variants and/or complex structural variants do exist in DMD or sarcoglycan genes. This study aimed to determine the genetic diagnosis of three patients from two unrelated families with a suspected sarcoglycanopathy or dystrophinopathy based on their clinical, radiological, and pathological features, for whom routine genomic detection approaches failed to yield a definite genetic diagnosis. Methods: Muscle-derived reverse transcription-polymerase chain reaction analysis and/or TA cloning of DMD, SGCA, SGCB, SGCD, and SGCG mRNA were performed to identify aberrant transcripts. Genomic Sanger sequencing around the aberrant transcripts was performed to detect possible splice-altering variants. Bioinformatic and segregation studies of the detected genomic variants were performed in both families. Results: In patients F1-II1 and F1-II2, we identified two novel pathogenic compound heterozygous variants in SGCB. One is a deep intronic splice-altering variant (DISV), c.243 + 1558C > T in intron 2 causing the activation of an 87-base pair (bp) pseudoexon, and the other one is a non-canonical splicing site variant, c.243 + 6T > A leading to the partial intron inclusion of 10-bp sequence. A novel DISV, c.243 + 1576C > G causing a 106-bp pseudoexon activation, and a nonsense variant in SGCB were identified in compound heterozygous state in patient F2-II1. Unexpectedly, the predicted nonsense variant, c.334C > T in exon 3, created a new donor splice site in exon 3 that was stronger than the natural one, resulting in a 97-bp deletion of exon 3 (r.333_429del). Conclusion: This is the first identification of rare exonic and DISVs in the SGCB gene.

Five Mesoporous Lanthanide Metal-Organic Frameworks: Syntheses, Structures, and Fluorescence Sensing of Fe3+, Cr2O72-, and H2O2 and Electrochemical Sensing of Trinitrophenol.

When a multicarboxylate aromatic ligand, 3,5-di(2',4'-dicarboxylphenyl)benzoic acid (H5L), was employed, five structurally similar lanthanide metal-organic frameworks (Ln-MOFs), {[Pr10L6(OH)3Cl(H2O)6]·4C2H8N}n (1), {[Nd10L6(OH)4 (H2O)9]·4C2H8N}n (2), {[Gd10L6(OH)4(H2O)3]·4C2H8N}n (3), {[Ho10L6(OH)4 (H2O)3]·4C2H8N}n (4) and {[Er10L6(OH)4(H2O)6]·4C2H8N}n (5), were synthesized and characterized. Single-crystal X-ray structural analyses disclosed that all five Ln-MOFs crystallize in the trigonal R3 space group. They have three-dimensional mesoporous structure featuring the coexistence of binuclear and tetranuclear species as inorganic building units. The mesoporous structure of 3 was verified by the gas adsorption experiment of N2. Fluorescence analysis showed that 3 can selectively detect Fe3+, Cr2O72-, and H2O2; furthermore, it can be used for the electrochemical detection of trinitrophenol. With the merit of an excellent highly sensitive detection performance, 3 has unpredictable application prospects in future research fields.

[Mechanism of Huangjing Qianshi Decoction in treatment of prediabetes based on network pharmacology and molecular docking].

This study analyzed the molecular mechanism of Huangjing Qianshi Decoction(HQD) in the treatment of prediabetes based on network pharmacology and molecular docking. The active components of HQD were identified and screened based on Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP, http://Lsp.nwu.edu.cn/tcmsp.php) and then the targets of the components and the genes related to prediabetes were retrieved, followed by identifying the common targets of the decoction and the disease. The medicinal component-target network was constructed by Cytoscape to screen key components. The protein-protein interaction(PPI) network was established by STRING and hub genes were identified by Cytoscape-CytoNCA, followed by Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) of the hub genes with R-clusterProfi-ler. Thereby, the possible signaling pathways were predicted and the molecular mechanism was deduced. A total of 79 active components of HQD and 785 diabetes-related targets of the components were screened out. The hub genes mainly involved the GO terms of tricarboxylic acid cycle, peptide binding, amide binding, hydrolase activity, and kinase activity regulation, and the KEGG pathways of AGE-RAGE signaling pathway, TNF signaling pathway, AMPK signaling pathway, IL-17 signaling pathway, and insulin signaling pathway. Western blot result showed that HQD-containing serum significantly reduced the expression of AKT1, AGE, and RAGE proteins in insulin resistance model cells. HQD's treatment of prediabetes is characterized by multiple pathways, multiple targets, and multiple levels. The main mechanism is that the components zhonghualiaoine, baicalein, kaempferol, and luteolin act on AKT1 and inhibit the AGE-RAGE axis.

The CGG repeat expansion in RILPL1 is associated with oculopharyngodistal myopathy type 4.

Recent studies indicate that CGG repeat expansions in LRP12, GIPC1, and NOTCH2NLC are associated with oculopharyngodistal myopathy (OPDM) types 1, 2, and 3, respectively. However, some clinicopathologically confirmed OPDM cases continue to have unknown genetic causes. Here, through a combination of long-read whole-genome sequencing (LRS), repeat-primed polymerase chain reaction (RP-PCR), and fluorescence amplicon length analysis PCR (AL-PCR), we found that a CGG repeat expansion in the 5' UTR of RILPL1 is associated with familial and simplex OPDM type 4 (OPDM4). The number of repeats ranged from 139 to 197. Methylation analysis indicates that the methylation levels in RILPL1 were unaltered in OPDM4 individuals. Analyses of muscle biopsies suggested that the expanded CGG repeat might be translated into a toxic poly-glycine protein that co-localizes with p62 in intranuclear inclusions. Moreover, analyses suggest that the toxic RNA gain-of-function effects also contributed to the pathogenesis of this disease. Intriguingly, all four types of OPDM have been found to be associated with the CGG repeat expansions located in 5' UTRs. This finding suggests that a common pathogenic mechanism, driven by the CGG repeat expansion, might underlie all cases of OPDM.

Genetic defects are common in myopathies with tubular aggregates.

OBJECTIVE: A group of genes have been reported to be associated with myopathies with tubular aggregates (TAs). Many cases with TAs still lack of genetic clarification. This study aims to explore the genetic background of cases with TAs in order to improve our knowledge of the pathogenesis of these rare pathological structures. METHODS: Thirty-three patients including two family members with biopsy confirmed TAs were collected. Whole-exome sequencing was performed on 31 unrelated index patients and a candidate gene search strategy was conducted. The identified variants were confirmed by Sanger sequencing. The wild-type and the mutant p.Ala11Thr of ALG14 were transfected into human embryonic kidney 293 cells (HEK293), and western blot analysis was performed to quantify protein expression levels. RESULTS: Eleven index cases (33%) were found to have pathogenic variant or likely pathogenic variants in STIM1, ORAI1, PGAM2, SCN4A, CASQ1 and ALG14. Among them, the c.764A>T (p.Glu255Val) in STIM1 and the c.1333G>C (p.Val445Leu) in SCN4A were novel. Western blot analysis showed that the expression of ALG14 protein was severely reduced in the mutant ALG14 HEK293 cells (p.Ala11Thr) compared with wild type. The ALG14 variants might be associated with TAs in patients with complex multisystem disorders. INTERPRETATION: This study expands the phenotypic and genotypic spectrums of myopathies with TAs. Our findings further confirm previous hypothesis that genes related with calcium signalling pathway and N-linked glycosylation pathway are the main genetic causes of myopathies with TAs.

Polygonatum sibiricum polysaccharides (PSP) improve the palmitic acid (PA)-induced inhibition of survival, inflammation, and glucose uptake in skeletal muscle cells.

Polygonatum sibiricum polysaccharides (PSP) can decrease the levels of fasting blood glucose, total cholesterol, and triglyceride (TG) in hyperlipidemic and diabetic animals. It can also reduce inflammatory cytokines and promote glucose uptake in adipocytes. However, the underlying molecular mechanisms of PSP in improving insulin resistance (IR) in skeletal muscle remain unclear. In this study, palmitic acid (PA) induced an IR model in L6 myotubes. After treatment, cell proliferation was measured using the CCK8. miR-340-3p, glucose transporter 4 (GLUT-4), and interleukin-1 receptor-associated kinase 3 (IRAK3) expression was measured by qRT-PCR. IRAK3 protein levels were measured by Western blotting. Glucose in the cell supernatant, TG concentration in L6 myotubes, and the levels of IL-1ß, IL-6, and TNF-α were measured by an ELISA. We found that cell survival, glucose uptake, and GLUT-4 expression in L6 myotubes were significantly suppressed, while lipid accumulation and inflammatory factor levels were enhanced by PA stimulation. Furthermore, PSP treatment markedly alleviated these effects. Interestingly, PSP also significantly reduced the upregulated expression of miR-340-3p in the L6 myotube model of IR. Furthermore, overexpression of miR-340-3p reversed the beneficial effects of PSP in the same IR model. miR-340-3p can bind to the 3'-untranslated regions of IRAK3. Additionally, PA treatment inhibited IRAK3 expression, whereas PSP treatment enhanced IRAK3 expression in L6 myotubes. Additionally, miR-340-3p also inhibited IRAK3 expression in L6 myotubes. Taken together, PSP improved inflammation and glucose uptake in PA-treated L6 myotubes by regulating miR-340-3p/IRAK3, suggesting that PSP may be suitable as a novel therapeutic agent for IR.