Heterozygous Seryl-tRNA Synthetase 1 Variants Cause Charcot-Marie-Tooth Disease.

OBJECTIVE: Despite the increasing number of genes associated with Charcot-Marie-Tooth (CMT) disease, many patients currently still lack appropriate genetic diagnosis for this disease. Autosomal dominant mutations in aminoacyl-tRNA synthetases (ARSs) have been implicated in CMT. Here, we describe causal missense mutations in the gene encoding seryl-tRNA synthetase 1 (SerRS) for 3 families affected with CMT. METHODS: Whole-exome sequencing was performed in 16 patients and 14 unaffected members of 3 unrelated families. The functional impact of the genetic variants identified was investigated using bioinformatic prediction tools and confirmed using cellular and biochemical assays. RESULTS: Combined linkage analysis for the 3 families revealed significant linkage (Zmax LOD = 6.9) between the genomic co-ordinates on chromosome 1: 108681600-110300504. Within the linkage region, heterozygous SerRS missense variants segregated with the clinical phenotype in the 3 families. The mutant SerRS proteins exhibited reduced aminoacylation activity and abnormal SerRS dimerization, which suggests the impairment of total protein synthesis and induction of eIF2α phosphorylation. INTERPRETATION: Our findings suggest the heterozygous SerRS variants identified represent a novel cause for autosomal dominant CMT. Mutant SerRS proteins are known to impact various molecular and cellular functions. Our findings provide significant advances on the current understanding of the molecular mechanisms associated with ARS-related CMT. ANN NEUROL 2023;93:244-256.

Biallelic COQ4 Variants in Hereditary Spastic Paraplegia: Clinical and Molecular Characterization.

BACKGROUND: Hereditary spastic paraplegias (HSP) are neurologic disorders characterized by progressive lower-extremity spasticity. Despite the identification of several HSP-related genes, many patients lack a genetic diagnosis. OBJECTIVES: The aims were to confirm the pathogenic role of biallelic COQ4 mutations in HSP and elucidate the clinical, genetic, and functional molecular features of COQ4-associated HSP. METHODS: Whole exome sequences of 310 index patients with HSP of unknown cause from three distinct populations were analyzed to identify potential HSP causal genes. Clinical data obtained from patients harboring candidate causal mutations were examined. Functional characterization of COQ4 variants was performed using bioinformatic tools, single-cell RNA sequencing, biochemical assays in cell lines, primary fibroblasts, induced pluripotent stem cell-derived pyramidal neurons, and zebrafish. RESULTS: Compound heterozygous variants in COQ4, which cosegregated with HSP in pedigrees, were identified in 7 patients from six unrelated families. Patients from four of the six families presented with pure HSP, whereas probands of the other two families exhibited complicated HSP with epilepsy or with cerebellar ataxia. In patient-derived fibroblasts and COQ4 knockout complementation lines, stable expression of these missense variants exerted loss-of-function effects, including mitochondrial reactive oxygen species accumulation, decreased mitochondrial membrane potential, and lower ubiquinone biosynthesis. Whereas differentiated pyramidal neurons expressed high COQ4 levels, coq4 knockdown zebrafish displayed severe motor dysfunction, reflecting motor neuron dysregulation. CONCLUSIONS: Our study confirms that loss-of-function, compound heterozygous, pathogenic COQ4 variants are causal for autosomal recessive pure and complicated HSP. Moreover, reduced COQ4 levels attributable to variants correspond with decreased ubiquinone biosynthesis, impaired mitochondrial function, and higher phenotypic disease severity. © 2023 International Parkinson and Movement Disorder Society.

Occurrence of Cassava (Manihot esculenta) Leaf Spot Disease Caused by Diaporthe ueckeri in China.

Cassava (Manihot esculenta) is a perennial crop of the family Euphorbiaceae, widely cultivated due to its phytopharmacological and economic values in China. In November 2022, a leaf spot disease on cassava was observed in Zhanjiang, Guangdong, China (21.17° N, 110.18° E), with 100% disease incidence. About 80 % of leaves were covered with spots on the infected plants. Typical symptoms initially appeared as irregular water-soaked lesions that became brown and whitish with the progress of the disease, lesions gradually expanded and coalesced, causing leaf withering, drying and final fall. Tissues (4 to 5 mm) were excised from the margin of lesions, sterilized in 3% H2O2 solution for 3 min, rinsed three times with sterile water, placed on potato dextrose agar (PDA) medium (containing 50mg/L penicillin), and incubated at 25-28 °C. Ten single hypha isolates with similar morphology were obtained and further purified as single conidium subcultures. The colony was grey whitish with sparse aerial mycelium and colony diameter reached 70.4 mm after four days incubation at 25-28℃ in the dark. Black pycnidia occurring as clusters were spherical or irregular, erumpent at maturity, often with a creamy whitish, conidial cirrus extruding from ostiole after 30-days incubation. Conidiophores were hyaline, smooth, unbranched. Alpha conidia were bi-guttulate, hyaline, ellipsoidal, aseptate, with dimensions of 5.1~7.5×1.9~3.4µm (mean 6.2×2.8 µm, n>50). Beta conidia were abundant, filiform, hyaline, smooth, curved in a hooked shape, with a truncate base and dimensions of 18.5-26.4 × 0.6-1.2µm (mean 23.4 × 1.0 µm, n= 40) . Gamma conidia were not observed. The morphological characteristics were similar to those of Diaporthe ueckeri (Udayanga et al. 2015). The internal transcribed spacer (ITS) region, large subunit (LSU) rRNA sequence, actin (ACT), calmodulin (CAL), histone H3 (HIS), translation elongation factor 1-alpha (TEF1-α), and ß-tubulin (TUB) genes of a representative isolate CCAS-MS-6 (ACCC 35497) were amplified and sequenced using primer pairs: ITS5/ITS4, LR0R/LR5, ACT-512F/ACT-783R, CAL228F/CAL737R, CYLH3F/ H3-1b, EF1-728F/ EF1-986R and Bt2a/Bt2b (Gao et al 2017；Udayanga et al 2014). All sequences were deposited in GenBank (OR361671, OR361672, and OR365605-9). BLAST search showed high similarities with sequences of Diaporthe ueckeri (Tab 1). Maximum likelihood analyses of the concatenated data of CAL, HIS, ITS, TEF and TUB using Mega 11 placed CCAS-MS-6 in the D. ueckeri clade. Thus, the fungus was identified as D. ueckeri. Three one-year old healthy plants were used for pathogenicity tests in pots. Two 15-day old leaves of each plant were cleaned with 75% alcohol, three sites on each leaf were wounded, and sites on one of the leaf were covered with fungal plugs from 15-day-old cultures on PDA, and sites on the other leaf with PDA plugs as a control. All plants were kept at ambient temperature (about 28℃) and covered with plastic bags containing sterile wet cotton to maintain the humidity. Seven days after inoculation, all inoculated sites showed symptoms of necrosis, while control sites showed no symptoms. The same fungus identified on the basis of morphological and molecular criteria was reisolated from symptomatic inoculated leaves. In China, D. ueckeri had been reported to cause diseases on Eucalyptus citriodora, Camellia sinensis, and Michelia shiluensis (Gao et al 2016; Liao et al 2023; Yi et al 2018), this is the first report on M. esculenta. The definition of the disease etiology is a prerequisite to develop effective management strategies.

Neoscytalidium dimidiatum causing stem canker on Hylocereus megalanthus in China.

Hylocereus megalanthus (syn. Selenecereus megalanthus), commonly known as Yanwo fruit (bird's nest fruit), is an important tropical fruit, which is popular and widely planted due to its high nutritional and economic value in southern China. In September 2022, a serious stem and fruit canker was observed on Ecuadorian variety of Yanwo fruit plant in a 0.2 ha orchard in Guangdong (N21°19'1.24" E110°7'28.49"). Almost all plants were infected and disease incidence of fruits and stems was about 80% and 90% respectively. Symptoms on the stem and fruits were small, circular or irregular, sunken, orangish brown spots that developed into cankers (Fig 1 A, B and C). Black pycnidia were embedded under the surface of the cankers at the initial stage, subsequently they became erumpent from the surface, and the infected parts rotted. Five symptomatic stems from five plants were collected, 0.2 cm2 tissues adjacent to cankers were surface sterilized and placed on potato dextrose agar (PDA) to incubate at 25 to 28 ℃. Fungal isolates each with similar morphology grew from 100% of the tissues. Colonies covered with aerial mycelium were grayish white, and then gradually turned to grayish black. Septate hyphae were hyaline to brown and constricted into arthroconidial chains. The arthroconidia were variously shaped and colored, orbicular to rectangular, hyaline to dark brown, thick-walled, and zero- to one- septate, averaging 7.7 × 3.6 µm (n>50) (Fig 1 D, E, F and G). To identify the fungus, the internal transcribed spacer region (ITS), translation elongation factor 1-alpha (tef1), beta-tubulin (tub2), histone H3 (his3) and chitin synthase (chs) gene of isolate ACCC 35488 and ACCC 35489 (Agricultural Culture Collection of China) were amplified and sequenced with primer pairs: ITS1/ITS4 (White et al. 1990), EF1-728F/EF2-rd (Carbone & Kohn 1999; O'Donnell et al.1998), TUB2Fd/ TUB4Rd（Aveskamp et al 2009）, CYLH3F/H3-1b (Crous et al. 2004) and CHS-79F/CHS-345R (Carbone & Kohn 1999) (ITS: OQ381102 and PP488350; tef1: OQ408545 and PP510454; tub2: OQ408546 and PP510455; his3: OQ408544 and PP510453; chs: OQ408543 and PP510452). Sequence Blastn results showed above 99% identical with those of Neoscytalidium dimidiatum ex-type strain CPC38666. Phylogenetic tree inferred from Maximum Likelihood analysis of the combined ITS, tub2 and tef1 sequences revealed two isolates clustered with N. dimidiatum (Fig 2). Pathogenicity was tested on healthy one-year-old cuttings and fruits of Ecuadorian variety at room temperature. Six sites were pin-pricked on each stem and fruit. Both wounded stems and fruits were inoculated with spore suspensions (106 spore/ml) and 6-mm fungal plugs respectively. Sterile water and agar were used as control. The test was repeated twice. Stems and fruits were enclosed in plastic boxes with 80% relative humidity. Symptoms described above were observed on inoculated stems and fruits at five days post inoculation (Fig 1 H and I). No symptoms developed on the controls. Neoscytaliudium dimidiatum was reisolated from the cankers with a frequency of 100% via morphological and molecular analysis. This is first report of stem and fruit canker caused by N. dimidiatum on H. megalanthus in China and this disease represents a serious risk of Yanwo fruit yield losses. This fungus is widespread occurring throughout the world causing diseases on a wide variety of plants. The finding will be helpful for its prevention and control.

Human neutrophil peptide 1 promotes immune sterilization in vivo by reducing the virulence of multidrug-resistant Klebsiella pneumoniae and increasing the ability of macrophages.

By studying the expression in patients and cell modeling in vitro, antimicrobial peptides for Klebsiella were screened. Killing curve and membrane permeability experiments are used to study the antibacterial effect of antimicrobial peptides in vitro. Cytotoxicity-related indicators including lipopolysaccharide (LPS), capsule polysaccharide (CPS), and outer membrane protein expression were measured. Intranasal inoculation of pneumoconiosis was used to construct a mouse infection model, and the survival rate and cytokine expression level were tested. Human neutrophil peptide 1 (HNP-1) showed a significant antibacterial effect, which improved the permeability of the outer membrane of K. pneumoniae. Moreover, HNP-1 decreased LPS, CPS content, and outer membrane proteins. K. pneumoniae infection decreased antimicrobial peptide, oxidative stress, and autophagy-related genes, while HNP-1 increased these genes. After coculture with macrophages, the endocytosis of macrophages is enhanced and the bacterial load is greater in the K. pneumoniae + peptide group. Besides, higher levels of pp38 and pp65 in the K. pneumoniae + peptide group. HNP-1 rescued the cytotoxicity induced by K. pneumoniae. The survival rate is significantly improved after K. pneumoniae is treated by HNP-1. All cytokines in the peptide group were significantly higher. HNP-1 promotes immune sterilization by reducing the virulence of multidrug-resistant K. pneumoniae and increasing the ability of macrophages.

MiR-181a-5p Delivered by Adipose-Derived Mesenchymal Stem Cell Exosomes Alleviates Klebsiella pneumonia Infection-Induced Lung Injury by Targeting STAT3 Signaling.

Background: Klebsiella pneumoniae (K. pneu) is a leading cause of gram-negative pneumonia, which requires effective treatment. Adipose-derived mesenchymal stem cell- (ADSC-) derived exosomal microRNAs (miRNAs) have presented the inhibitory effect of multiple diseases. However, the function of ADSC-derived exosomal miRNAs in K. pneu remains unclear. Aim: In this study, we aimed to explore the effect of ADSC-derived exosomal miR-181-5p on K. pneu infection-induced lung injury. Methods: C57BL/6 mouse model was established by infection of K. pneu. ADSCs and exosomes were extracted and characterized in vitro. The translocation of ADSC-derived exosomes to bone marrow-derived macrophages (BMDMs) was detected. The level of miR-181a-5p was detected by real-time PCR. The secretion of inflammatory factors was determined by ELISA. The interaction between miR-181a-5p with STAT3 was identified. Results: We successfully isolated the ADSCs that express positive markers CD90 and CD105 rather than CD31 and CD45. The exosomal miR-181a-5p secreted by ADSCs were internalized by BMDM and K. pneu infection stimulated the miR-181a-5p level in bronchoalveolar lavage fluid (BALF) and BMDM. ADSC-derived exosomal miR-181a-5p repressed pulmonary outgrowth and dissemination of K. pneu infection in mice, repressed cellular infiltration in lung tissue, and attenuated the inflammasome activity and the levels of IL-1ß and IL-18 in the lung. Mechanically, miR-181a-5p was able to inhibit STAT3 expression at posttranscriptional levels and repressed Nlrp3 and Asc expression in BMDM. Conclusion: Consequently, we concluded that ADSC-derived exosomal miR-181a-5p alleviated Klebsiella pneumonia infection-induced lung injury by targeting STAT3 signaling. ADSC-derived exosomal miR-181a-5p may serve as a potential candidate for the treatment of Klebsiella pneumonia infection-induced lung injury.

Effects of dietary nucleotides on growth performance, immune response, intestinal morphology and disease resistance of juvenile largemouth bass, Micropterus salmoides.

An 8 week feeding trial was carried out to investigate the effects of dietary nucleotides on growth performance, intestinal morphology, immune response and disease resistance of juvenile largemouth bass, Micropterus salmoides. Five grades of dietary nucleotide levels were designed as 0, 0.2, 0.4, 0.8 and 1.2 g kg-1 , respectively. Each group had 3 replicates, with 40 fish in each replicate. After the feeding experiment, 15 fish from each tank were infected with Aeromonas hydrophila for 14 days. The results indicated that fish fed the diets containing 0.4, 0.8 and 1.2 g kg-1 nucleotides had higher growth performance and feed utilization than those fed the control diet. Nonetheless, there were no significant differences in survival between all the groups, although fish fed the diets with all-level nucleotides obtained higher survival than those fed the control diet. Dietary nucleotides significantly affected the superoxide dismutase, acid phosphatase and catalase activities in serum but not the malondialdehyde content. Fish fed the 0.4 g kg-1 nucleotide diets had the highest fold height, enterocyte height and muscular layer thickness significantly. The average mortality of largemouth bass infected with A. hydrophila was significantly influenced by dietary nucleotides. The mortality was significantly higher in the control group (91.11%) and 0.02% nucleotide group (73.11%) followed by the other groups and lowest in the 0.8 g kg-1 nucleotide group. In summary, dietary 0.4-0.8 g kg-1 nucleotides promoted growth performance, enhanced immunity and improved intestinal morphology and disease resistance of largemouth bass.

Dual pathways mediate ß-amyloid stimulated glutathione release from astrocytes.

Oxidative stress plays an important role in the progression of Alzheimer's disease (AD) and other neurodegenerative conditions. Glutathione (GSH), the major antioxidant in the central nervous system, is primarily synthesized and released by astrocytes. We determined if ß-amyloid (Aß42), crucially involved in Alzheimer's disease, affected GSH release. Monomeric Aß (mAß) stimulated GSH release from cultured cortical astrocytes more effectively than oligomeric Aß (oAß) or fibrillary Aß (fAß). Monomeric Aß increased the expression of the transporter ABCC1 (also referred to as MRP1) that is the main pathway for GSH release. GSH release from astrocytes, with or without mAß stimulation, was reduced by pharmacological inhibition of ABCC1. Astrocytes robustly express connexin proteins, especially connexin43 (Cx43), and mAß also stimulated Cx43 hemichannel-mediated glutamate and GSH release. Aß-stimulation facilitated hemichannel opening in the presence of normal extracellular calcium by reducing astrocyte cholesterol level. Aß treatment did not alter the intracellular concentration of reduced or oxidized glutathione. Using a mouse model of AD with early onset Aß deposition (5xFAD), we found that cortical ABCC1 was significantly increased in temporal register with the surge of Aß levels in these mice. ABCC1 levels remained elevated from 1.5 to 3.5 months of age in 5xFAD mice, before plunging to subcontrol levels when amyloid plaques appeared. Similarly, in cultured astrocytes, prolonged incubation with aggregated Aß, but not mAß, reduced induction of ABCC1 expression. These results support the hypothesis that in the early stage of AD pathogenesis, less aggregated Aß increases GSH release from astrocytes (via ABCC1 transporters and Cx43 hemichannels) providing temporary protection from oxidative stress which promotes AD development.

Tripchlorolide ameliorates experimental autoimmune encephalomyelitis by down-regulating ERK1/2-NF-κB and JAK/STAT signaling pathways.

Tripchlorolide (T4), an extract of the natural herb Tripterygium wilfordii Hook F, has been found to possess anti-inflammatory and immunosuppressive actions. In the current study, these actions were evaluated in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis by scoring the clinical signs, observing the infiltration of inflammatory cells and myelin sheath in the lumbar spinal cord of EAE mice. The results demonstrated that T4 (at a dose of 40 µg/kg) significantly reduced the severity of EAE and slowed down the ongoing EAE. Further analysis showed that T4 suppressed the mRNA and protein levels of the transcription factors T-bet and RoRrt and mRNA levels of IFN-γ and IL-17 in the spinal cords. Furthermore, T4 down-regulated the ERK1/2-NF-κB and JAK/STAT signaling pathways. At 40 µg/kg, T4 did not induce side effects on hematological parameters. These findings suggest that T4 ameliorates EAE by immunosuppression, providing a new insight into T4 application in multiple sclerosis treatment.

Curcumin inhibits appoptosin-induced apoptosis via upregulating heme oxygenase-1 expression in SH-SY5Y cells.

AIM: Appoptosin (SLC25A38) is a pro-apoptotic protein, which is upregulated in Alzheimer's disease (AD) brains and plays an important role in promoting the pathological progress of AD. The aim of this study was to investigate the effects of curcumin from the rhizome of Curcuma longa on appoptosin-induced apoptosis in SH-SY5Y cells. METHODS: SH-SY5Y cells were pretreated with curcumin, then transfected with appoptosin or vector. The apoptotic cells were detected with Annexin V staining analysis by flow cytometry. The expression of cleaved caspase-3, appoptosin, heme oxygenase-1 (HO-1) was examined using Western blotting. Intracellular level of ROS was measured with DCFH-DA staining by flow cytometry analysis. Mitochondrial membrane potential (ΔΨm) was detected with JC-1 staining under a fluorescence microscope and quantified by fluorescence ratio detection.Overexpression of appoptosin in SH-SY5Y cells markedly increased cell apoptosis accompanied by reduced HO-1 expression, increased intracellular heme level, ROS overproduction and ΔΨm impairment. Treatment of SH-SY5Y cells with curcumin (2.5-20 µmol/L) for 24 h did not significantly affect their viability. However, pretreatment with curcumin (2.5-20 µmol/L) dose-dependently attenuated all above-mentioned pathological changes in appoptosin-transfected SH-SY5Y cells. RESULTS: Overexpression of appoptosin in SH-SY5Y cells markedly increased cell apoptosis accompanied by reduced HO-1 expression, increased intracellular heme level, ROS overproduction and ΔΨm impairment. Treatment of SH-SY5Y cells with curcumin (2.5-20 µmol/L) for 24 h did not significantly affect their viability. However, pretreatment with curcumin (2.5-20 µmol/L) dose-dependently attenuated all above-mentioned pathological changes in appoptosin-transfected SH-SY5Y cells. CONCLUSION: Curcumin inhibits appoptosin-induced apoptosis in SH-SY5Y cells by upregulating the expression of HO-1, reducing the production of intracellular heme and ROS, and preventing the ΔΨm loss.

[Molecular diagnosis of children with unexplained intellectual disability/ developmental delay by array-CGH].

OBJECTIVE: To analyze the potential pathogenic genomic imbalance in children with unexplained intellectual disability (ID) and/or developmental delay (DD) and its association with phenotypes, and to investigate the value of array-based comparative genomic hybridization (array-CGH) in clinical molecular genetic diagnosis. METHODS: The whole genome of 16 children with ID/DD was scanned by the array-CGH for detection of genomic copy number variations (CNVs), and the revealed genomic imbalance was confirmed by multiplex ligation-dependent probe amplification. RESULTS: G-band karyotyping of peripheral blood cells showed no abnormalities in the 16 children. The results of the array-CGH revealed that 6 (38%) of the 16 patients had genomic CNVs, and 3 cases of CNVs were normal polymorphic changes; 1 CNV was a microdeletion of 4p16.3, which was the critical region for Wolf-Hirschhorn syndrome, and 1 CNV was a microdeletion of 7q11.23, which was the critical region for Williams-Beuren syndrome. Moreover, a CNV was identified with two duplications at 2q22.2 and 15q21.3 in a boy, which proved to have a clinical significance due to its association with ID, brain DD, unusual facies, cryptorchidism, irregular dentition, etc. CONCLUSIONS: Array-CGH allows for the etiological diagnosis in some of the children with unexplained ID/DD. As a high-throughput and rapid tool, it has a great clinical significance in the etiological diagnosis of ID/DD.

Whole dystrophin gene analysis by next-generation sequencing: a comprehensive genetic diagnosis of Duchenne and Becker muscular dystrophy.

Duchenne/Becker muscular dystrophies are the most frequent inherited neuromuscular diseases caused by mutations of the dystrophin gene. However, approximately 30% of patients with the disease do not receive a molecular diagnosis because of the complex mutational spectrum and the large size of the gene. The introduction and use of next-generation sequencing have advanced clinical genetic research and might be a suitable method for the detection of various types of mutations in the dystrophin gene. To identify the mutational spectrum using a single platform, whole dystrophin gene sequencing was performed using next-generation sequencing. The entire dystrophin gene, including all exons, introns and promoter regions, was target enriched using a DMD whole gene enrichment kit. The enrichment libraries were sequenced on an Illumina HiSeq 2000 sequencer using paired read 100 bp sequencing. We studied 26 patients: 21 had known large deletion/duplications and 5 did not have detectable large deletion/duplications by multiplex ligation-dependent probe amplification technology (MLPA). We applied whole dystrophin gene analysis by next-generation sequencing to the five patients who did not have detectable large deletion/duplications and to five randomly chosen patients from the 21 who did have large deletion/duplications. The sequencing data covered almost 100% of the exonic region of the dystrophin gene by ≥10 reads with a mean read depth of 147. Five small mutations were identified in the first five patients, of which four variants were unreported in the dmd.nl database. The deleted or duplicated exons and the breakpoints in the five large deletion/duplication patients were precisely identified. Whole dystrophin gene sequencing by next-generation sequencing may be a useful tool for the genetic diagnosis of Duchenne and Becker muscular dystrophies.

Klebsiella pneumoniae alters zebrafish circadian rhythm via inflammatory pathways and is dependent on light cues.

Klebsiella pneumoniae is an opportunistic pathogen causing severe infections. The circadian rhythm is the internal rhythm mechanism of an organism and plays an important role in coping with changes in the 24-h circadian rhythm. Disruption of the circadian rhythm can lead to immune, behavioral, mental, and other related disorders. Whether K. pneumoniae can disrupt the circadian rhythm after infection remains unclear. Here, we examined the effects of K. pneumoniae NTUH-K2044 infection on biological rhythm and inflammation in zebrafish using behavioral assays, quantitative real-time reverse transcription PCR, neutrophil and macrophage transgenic fish, and drug treatment. The results showed that K. pneumoniae infection decreased the motor activity of zebrafish and reduced the circadian rhythm amplitude, phase, and period. The expression of core circadian rhythm-associated genes increased under light-dark conditions, whereas they were downregulated under continuous darkness. Analysis of Klebsiella pneumoniae-mediated inflammation using Tg(mpx:EGFP) and Tg(mpeg:EGFP) transgenic zebrafish, expressing fluorescent neutrophils and macrophages, respectively, showed increased induction of inflammatory cells, upregulated expression of inflammatory factor genes, and stronger inflammatory responses under light-dark conditions. These effects were reversed by the anti-inflammatory drug G6PDi-1, and the expression of clock genes following K. pneumoniae treatment was disrupted. We determined the relationship among K. pneumoniae, inflammation, and the circadian rhythm, providing a theoretical reference for studying circadian rhythm disorders caused by inflammation.

[Profiles of reproduction-related mRNA expressions in hypothalamus of female mice with advancing age].

OBJECTIVE: To explore the effects of aging on the levels of reproduction-related mRNA genes including Gnrh, KISS1/KISS1r, estrogen receptor-alpha (ERα), estrogen receptor-beta (ERß) and progesterone receptor (PR) in hypothalamus. METHODS: Proestrus and metestrus in young (3-4 months) and middle-aged (10-11 months) female mice and diestrus in senile (18-19 months) female mice were observed. And the levels of related mRNA genes in preoptic area anterior hypothalamus (POA-AH) and medial basal hypothalamus (MBH) were determined by real-time polymerase chain reaction (RT-PCR). RESULTS: In middle-aged mice on proestrus, the level of Gnrh mRNA in POA-AH (0.896 ± 0.049) was significantly lower than that in young mice (1.228 ± 0.147, P = 0.049). The level of ERα mRNA in POA-AH decreased in young mice on proestrus whereas increased in middle-aged mice (0.432 ± 0.063 vs 0.603 ± 0.018, P = 0.016). The level of ERα mRNA of POA-AH, both in middle-aged mice (0.432 ± 0.063, P = 0.014) and senile mice (0.403 ± 0.145, P = 0.020) on diestrus, were significantly lower than that in young mice. The PR mRNA expression in middle-aged mice on proestrus (1.037 ± 0.037) was markedly lower than that in young mice (1.251 ± 0.081, P = 0.031) . In senile mice, the levels of Gnrh mRNA (1.520 ± 0.146, P = 0.004) and ERß mRNA (1.572 ± 0.184, P = 0.011) increased in POA-AH compared with that in young mice on metestrus. Aging had no effect upon KISS1 and KISS1r mRNA levels in POA-AH. In contrast, KISS1 mRNA level of MBH in middle-aged (1.663 ± 0.398, P = 0.037) and senile (2.622 ± 0.454, P = 0.014) mice obviously increased compared with the young mice group. CONCLUSION: Higher levels of ERα mRNA and decreases of PR and Gnrh mRNA in POA-AH in middle-aged mice on proestrus may play an important role in declining reproductive function.

HnRNPK is involved in stress-induced depression-like behavior via ERK-BDNF pathway in mice.

As a ubiquitous RNA-binding protein, heterogeneous nuclear ribonucleoprotein K (hnRNPK) interacts with numerous nucleic acids and proteins and is involved in various cellular functions. Available literature indicates that it can regulate dendritic spine density through the extracellular signal-regulating kinase (ERK) - brain-derived neurotrophic factor (BDNF) pathway, which is crucial to retain the synaptic plasticity in patients with major depressive disorder (MDD) and mouse depression models. However, ERK upstream regulatory kinase has not been fully elucidated. Furthermore, it remains unexplored whether hnRNPK may impact the depressive condition via the ERK pathway. The present study addressed this issue by integrating approaches of genetics, molecular biology, behavioral testing. We found that hnRNPK in the brain was mainly distributed in the hippocampal neurons; that it was significantly downregulated in mice that displayed stress-induced depression-like behaviors; and that the level of hnRNPK markedly decreased in MDD patients from the GEO database. Further in vivo and in vitro analyses revealed that the changes in the expressions of BDNF and PSD95 and in the phosphorylation of ERK (Thr202/Tyr204) paralleled the variation of hnRNPK levels in the ventral hippocampal neurons in mice with depression-like behaviors. Finally, esketamine treatment significantly increased the level of hnRNPK in mice. These findings evidence that hnRNPK involved in the pathogenesis of depression via the ERK-BDNF pathway, pinpointing hnRNPK as a potential therapeutic target in treating MDD patients.

Elizabethkingia anophelis outer membrane vesicles as a novel vaccine candidate against infection: insights into immune response and potential for passive immunity.

IMPORTANCE: Elizabethkingia anophelis, a Gram-negative pathogen, causes infections such as bacteraemia, pneumonia, and neonatal meningitis. The pathogen resists most antimicrobial classes, making novel approaches urgently needed. In natural settings, Gram-negative bacteria secrete outer membrane vesicles (OMVs) that carry important molecules in the bacterial life cycle. These OMVs are enriched with proteins involved in virulence, survival, and carbohydrate metabolism, making them a promising source for vaccine development against the pathogen. This study investigated the efficacy of imipenem-induced OMVs (iOMVs) as a vaccine candidate against E. anophelis infection in a mouse pneumonia model. Mice immunized with iOMVs were completely protected during lethal-dose challenges. Passive immunization with hyperimmune sera and splenocytes conferred protection against lethal pneumonia. Further investigation is needed to understand the mechanisms underlying the protective effects of iOMV-induced passive immunity, such as the action on specific antibody subclasses or T cell subsets.

Meplazumab in hospitalized adults with severe COVID-19 (DEFLECT): a multicenter, seamless phase 2/3, randomized, third-party double-blind clinical trial.

Meplazumab, a humanized CD147 antibody, has shown favourable safety and efficacy in our previous clinical studies. In DEFLECT (NCT04586153), 167 patients with severe COVID-19 were enroled and randomized to receive three dosages of meplazumab and a placebo. Meplazumab at 0.12 mg/kg, compared to the placebo group, showed clinical benefits in significantly reducing mortality by 83.6% (2.4% vs. 14.6%, p = 0.0150), increasing the proportion of patients alive and discharged without supplemental oxygen (82.9% vs. 70.7%, p = 0.0337) and increasing the proportion of patients who achieved sustained clinical improvement (41.5% vs. 31.7%). The response rate in the 0.2 mg/kg group was relatively increased by 16.0% compared with the placebo group (53.7% vs. 46.3%). Meplazumab also reduced the viral loads and multiple cytokine levels. Compare with the placebo group, the 0.3 mg/kg significantly increased the virus negative rate by 40.6% (p = 0.0363) and reduced IL-8 level (p = 0.0460); the 0.2 mg/kg increased the negative conversion rate by 36.9%, and reduced IL-4 (p = 0.0365) and IL-8 levels (p = 0.0484). In this study, the adverse events occurred at a comparable rate across the four groups, with no unexpected safety findings observed. In conclusion, meplazumab promoted COVID-19 convalescence and reduced mortality, viral load, and cytokine levels in severe COVID-19 population with good safety profile.

Ginsenoside Rb1 selectively inhibits the activity of L-type voltage-gated calcium channels in cultured rat hippocampal neurons.

AIM: To investigate the effect of ginsenoside Rb1 on voltage-gated calcium currents in cultured rat hippocampal neurons and the modulatory mechanism. METHODS: Cultured hippocampal neurons were prepared from Sprague Dawley rat embryos. Whole-cell configuration of the patch-clamp technique was used to record the voltage-gated calcium currents (VGCCs) from the hippocampal neurons,and the effect of Rb1 was examined. RESULTS: Rb1 (2-100 µmol/L) inhibited VGCCs in a concentration-dependent manner, and the current was mostly recovered upon wash-out. The specific L-type Ca(2+) channel inhibitor nifedipine (10 µmol/L) occluded Rb1-induced inhibition on VGCCs. Neither the selective N-type Ca(2+) channel blocker ω-conotoxin-GVIA (1 µmol/L), nor the selective P/Q-type Ca(2+) channel blocker ω-agatoxin IVA (30 nmol/L) diminished Rb1-sensitive VGCCs. Rb1 induced a leftward shift of the steady-state inactivation curve of I(Ca) to a negative potential without affecting its activation kinetics or reversal potential in the I-V curve. The inhibitory effect of Rb1 was neither abolished by the adenylyl cyclase activator forskolin (10 µmol/L), nor by the PKA inhibitor H-89 (10 µmol/L). CONCLUSION: Ginsenoside Rb1 selectively inhibits the activity of L-type voltage-gated calcium channels, without affecting the N-type or P/Q-type Ca(2+) channels in hippocampal neurons. cAMP-PKA signaling pathway is not involved in this effect.

The effects of caloric restriction and a high-fat diet on ovarian lifespan and the expression of SIRT1 and SIRT6 proteins in rats.

BACKGROUND AND AIMS: Caloric restriction (CR) extends mammals' lifespans and suppresses ovary development. Sirtuins are involved in these mechanisms. If, and to what extent CR affects ovarian lifespan and follicle development is largely unknown. We investigated the effects of moderate and severe caloric restriction compared with a high-fat dietary regimen on ovarian follicle reserves in rats. METHODS: Female Sprague-Dawley rats (n=48) randomly divided into four groups including normal control (NC), 25% caloric restriction (MCR), 45% CR (SCR) and high-fat diet (HF) were maintained on these regimens for 2 months. RESULTS: Histological analysis showed that both the 25 and 45% CR rats had a significantly higher percentage of primordial follicles and a larger number of healthy follicles than the NC rats, whereas the HF rats did not differ significantly from the NC rats. Immunohistochemical analysis revealed that SIRT1 and SIRT6 proteins were present in the nucleus and cytoplasm of the oocytes. The 25% CR diet increased the expression of both SIRT1 and SIRT6 in the ovary, whereas the 45% CR and HF diets caused a decrease in SIRT1 expression. The level of SIRT6 protein did not change with the 45% CR diet, and it appeared slightly lower in the HF than in the NC groups. CONCLUSIONS: Caloric restriction may inhibit the transition from primordial to developing follicles and extend the entire growth phase of a follicle to preserve the reserve of germ cells. SIRT1 and SIRT6 are both associated with these effects.

[Diverse components of voltage-gated calcium channel currents in primary cultured hippocampal neurons].

The present study was to record and separate the voltage-gated calcium channel currents (VGCCs) in primary cultured hippocampal neurons. An improved method is described for efficient and stable recording of VGCCs from primary cultured hippocampal neurons. The procedure allows the obtained hippocampal neurons overcome the defects from acutely isolated hippocampal neurons and currents do not rundown apparently after 20 min of membrane rupture. Using whole-cell configurations of patch clamp technique, it is shown that the method does not damage the neuron membrane electrical properties, and successfully records a variety of VGCCs components in hippocampal neurons (such as L, N, P/Q, T, etc.).