Agomirs upregulating carboxypeptidase E expression rescue hippocampal neurogenesis and memory deficits in Alzheimer's disease.

BACKGROUND: Adult neurogenesis occurs in the subventricular zone (SVZ) and the subgranular zone of the dentate gyrus in the hippocampus. The neuronal stem cells in these two neurogenic niches respond differently to various physiological and pathological stimuli. Recently, we have found that the decrement of carboxypeptidase E (CPE) with aging impairs the maturation of brain-derived neurotrophic factor (BDNF) and neurogenesis in the SVZ. However, it remains unknown whether these events occur in the hippocampus, and what the role of CPE is in the adult hippocampal neurogenesis in the context of Alzheimer's disease (AD). METHODS: In vivo screening was performed to search for miRNA mimics capable of upregulating CPE expression and promoting neurogenesis in both neurogenic niches. Among these, two agomirs were further assessed for their effects on hippocampal neurogenesis in the context of AD. We also explored whether these two agomirs could ameliorate behavioral symptoms and AD pathology in mice, using direct intracerebroventricular injection or by non-invasive intranasal instillation. RESULTS: Restoration of CPE expression in the hippocampus improved BDNF maturation and boosted adult hippocampal neurogenesis. By screening the miRNA mimics targeting the 5'UTR region of Cpe gene, we developed two agomirs that were capable of upregulating CPE expression. The two agomirs significantly rescued adult neurogenesis and cognition, showing multiple beneficial effects against the AD-associated pathologies in APP/PS1 mice. Of note, noninvasive approach via intranasal delivery of these agomirs improved the behavioral and neurocognitive functions of APP/PS1 mice. CONCLUSIONS: CPE may regulate adult hippocampal neurogenesis via the CPE-BDNF-TrkB signaling pathway. This study supports the prospect of developing miRNA agomirs targeting CPE as biopharmaceuticals to counteract aging- and disease-related neurological decline in human brains.

ER Ca2+ overload activates the IRE1α signaling and promotes cell survival.

BACKGROUND: Maintaining homeostasis of Ca2+ stores in the endoplasmic reticulum (ER) is crucial for proper Ca2+ signaling and key cellular functions. Although Ca2+ depletion has been known to cause ER stress which in turn activates the unfolded protein response (UPR), how UPR sensors/transducers respond to excess Ca2+ when ER stores are overloaded remain largely unclear. RESULTS: Here, we report for the first time that overloading of ER Ca2+ can directly sensitize the IRE1α-XBP1 axis. The overloaded ER Ca2+ in TMCO1-deficient cells can cause BiP dissociation from IRE1α, promote the dimerization and stability of the IRE1α protein, and boost IRE1α activation. Intriguingly, attenuation of the over-activated IRE1α-XBP1s signaling by a IRE1α inhibitor can cause a significant cell death in TMCO1-deficient cells. CONCLUSIONS: Our data establish a causal link between excess Ca2+ in ER stores and the selective activation of IRE1α-XBP1 axis, underscoring an unexpected role of overload of ER Ca2+ in IRE1α activation and in preventing cell death.

ERp44 Regulates the Proliferation, Migration, Invasion, and Apoptosis of Gastric Cancer Cells Via Activation of ER Stress.

Gastric cancer (GC) is one of the most prevalent malignancies worldwide. Endoplasmic reticulum (ER) stress plays a key role in the progression of GC. Rapid proliferation of tumor cells interferes with ER homeostasis, leading to ER stress and triggering unfolded protein response. Therefore, it is very necessary to investigate abnormally expressed ER resident proteins (ERp) in cancer cells. This study aimed to investigate the possible roles of ERp44. The mRNA and protein expression of genes were detected using qRT-PCR and western blot. Cell apoptosis was calculated using flow cytometry. Cell proliferation was determined using CCK-8 and colony formation assay. Cell migration was detected by wound healing, and cell invasion was measured by transwell assay. We found that ERp44 was obviously decreased in GC tissues. Furthermore, ERp44 overexpression distinctly suppressed the proliferation, migration, and invasion of MGC-803 and KATO III cells. In contrast, apoptosis was promoted by ERp44 overexpression. Furthermore, mechanistic studies revealed that overexpression of ERp44 inhibited malignant biological processes by regulating the eIF-2α/CHOP signaling pathway. Taken together, our data demonstrated that ERp44 regulated the proliferation, migration, invasion, and apoptosis via ERp44/eIF-2α/CHOP axis in GC. Targeting the ERp44and ER stress may be a promising strategy for GC.

Clinical characteristics of nucleic acid negative neonates delivered by pregnant women infected with SARS-CoV-2 in Sanya, Hainan / 中国热带医学

@#Abstract: Objective　To explore the clinical characteristics of nucleic acid negative newborns delivered by pregnant women infected with SARS-CoV-2 (Omicron variant BA. 5.1.3) in Sanya area, and to provide evidence for understanding its clinical characteristics. Methods　A retrospective analysis was performed on 14 neonates with negative nucleic acid delivered by pregnant women who tested positive for SARS-CoV-2 (Omicron variant BA.5.1.3) in Sanya Central Hospital (the Third People's Hospital of Hainan Province) from June 2022 to September 2022 (observation group, n=14). The corresponding nucleic acid-negative newborns delivered by pregnant women detected negative with SARS-CoV-2 (Omicronon variant strain BA.5.1.3) were set as the control group (n=56), and the general data and clinical characteristics of neonates in the two groups were compared. Results　There was no significant difference between the observation group and the control group in pregnancy diabetes, pregnancy induced hypertension, gestational pre-eclampsia, fetal intrauterine distress, premature rupture of membranes (P>0.05); there was no significant difference between the observation group and the control group in terms of sex, gestational age, birth weight, age, mode of delivery, birth Apgar score, heart screening, pulmonary disease, glucose 6-phosphate dehydrogenase (G6PD) deficiency, thalassemia, breast milk jaundice, hemolytic jaundice (P>0.05). The bilirubin level, blue light irradiation cases and the duration of blue light irradiation of the newborns in the observation group at 7 days after birth were higher than those in the control group (P<0.05); the ratio of blood oxygen saturation ≥ 90% in the observation group was lower than that in the control group (21.43% vs 89.29%, P<0.05), and the ratio of blood oxygen saturation occasionally<90% was higher than that in the control group (57.14% vs 10.71%, P<0.05). The ratio of blood oxygen saturation<90% had no significant difference compared with that in the control group (7.14% vs 0, P>0.05), and the ratio of blood oxygen saturation reduced to the required oxygen uptake was higher than that in the control group (14.29% vs 0, P<0.05). Conclusions　The jaundice manifestation of the nucleic acid-negative newborns delivered by pregnant women infected with SARS-CoV-2 (Omicronon variant strain BA.5.1.3) in Sanya area is relatively obvious, with blood oxygen saturation easily lower than 90% and even requiring oxygen inhalation in severe cases.

A case report of 4-day-old neonate infected with Omicron variant BA.5.1.3 / 中国热带医学

@#Abstract: Objective　To understand the clinical manifestations, symptoms, treatment and recovery of neonates infected with Omicron variant (BA.5.1.3) of SARS-CoV-2, and provide a certain reference for subsequent diagnosis and treatment of related diseases. Methods　The clinical manifestations, epidemiology, auxiliary examinations, and treatment processes of the neonate aged 4-day-old who was community-acquired infection of variant BA.5.1.3 in Sanya was retrospectively analyzed. Results　The neonate's mother was identified as a close contact with patients with coronavirus disease 2019 (COVID-19) one hour before delivery, and tested positive for nucleic acid within 24 hours after delivery. But her breast milk, amniotic fluid, placenta, and umbilical cord were not detected for nucleic acid test after delivery. The nucleic acid test of the neonate was negative within 24 hours after birth. Then he was transferred to the hotel for isolation. Before the transfer, the mother and baby stayed in the same room and ate breast milk but the mother did not wear any mask. The neonate didn't have nucleic acid test on the second and third days of his life, and the nucleic acid test of the neonate was positive on the fourth day, negative on the fifth day, and positive on the sixth day. Then he was transferred to the designated hospital of COVID-19 for treatment. The neonate had no cough, no fever, yellow skin, abdominal distension, general breast feeding, and good reaction. On admission, the laboratory examination showed that blood routine examination and electrolyte were normal, and the myocardial enzyme and liver and kidney functions were normal. The bilirubin was significantly increased (449.3 μmol/L). The nucleic acid test of the neonate was positive and his chest imaging results were normal. The treatment measures were mainly isolation, feeding, blue light fading, close monitoring of vital signs, and antiviral drugs were administered. Jaundice subsided and abdominal distension was relieved after 6 d of treatment, and the treatment process was smooth without complications. Conclusions　The results suggest that the neonates are susceptible to Omicron variant BA.5.1.3 and prone to aggregation. The evidence of vertical transmission is insufficient and the clinical symptoms of neonates infected with Omicron variant BA.5.1.3 are mid, with no involvement of organ damage of the heart, liver, kidney, brain, and other organs.

Efficacy and safety of nasal intermittent positive pressure ventilation and nasal continuous positive airway pressure ventilation in neonatal respiratory distress syndrome: a systematic review and meta-analysis.

Background: The efficacies of nasal continuous positive airway pressure (NCPAP) and nasal intermittent positive pressure ventilation (NIPPV) in neonatal respiratory distress syndrome (RDS) are controversial. The reasons for controversy may be the selection bias of research objects and the small sample size. Methods: Literature retrieval was performed in PubMed, EMBASE, Medline, Central, China National Knowledge Infrastructure (CNKI), Wanfang and China Science Digital Library (CSDL) databases. Inclusion criteria: (I) literatures involving subjects who were newborns with RDS; (II) studies that had established both experimental and control groups; (III) the intervention measures of the experimental and control groups were NIPPV and NCPAP, respectively; (IV) the results included the incidence of intubation, bronchopulmonary dysplasia (BPD), or mortality; and (V) randomized controlled trials (RCTs). The chi-square test was applied for heterogeneity test. Publication bias assessment was conducted by funnel plot and Egger's test. The revised Cochrane risk of bias tool for individually randomized, parallel group trials (RoB2.0) was used to evaluate the risk of bias of the included RCT research. Results: A total of 10 literatures were included for analysis, including 1,104 patients, 557 in the NIPPV group and 547 in the NCPAP group. Among the literatures, 2 literatures had low risk of bias, 2 literatures had high risk of bias, and the rest had uncertain risk of bias. Compared to NCPAP, NIPPV reduced the incidence of neonatal intubation in RDS [risk ratio (RR) =0.57, 95% confidence interval (CI): 0.46-0.71, Z=5.11, P<0.00001]. There was no statistically significant heterogeneity (P=0.13, I2=36%) or publication bias (P<0.05) among the studies. Compared with NCPAP, NIPPV reduced the incidence of BPD in RDS (RR =0.72, 95% CI: 0.57-0.91, Z=2.70, P=0.007). There was no statistically significant heterogeneity (P=0.10, I2=41%) or publication bias (P>0.05) among the studies. NIPPV reduced the neonatal mortality rate of RDS (RR =0.55, 95% CI: 0.31-0.97, Z=2.08, P=0.04). There was no statistically significant heterogeneity (P=0.20, I2=38%) or publication bias (P>0.05) among the studies. Discussion: Compared with NCPAP, NIPPV can reduce the incidence of intubation, BPD, and mortality. The conclusions need to be confirmed via high-quality RCTs.

Ca2+ homeostasis maintained by TMCO1 underlies corpus callosum development via ERK signaling.

Transmembrane of coiled-coil domains 1 (TMCO1) plays an important role in maintaining homeostasis of calcium (Ca2+) stores in the endoplasmic reticulum (ER). TMCO1-defect syndrome shares multiple features with human cerebro-facio-thoracic (CFT) dysplasia, including abnormal corpus callosum (CC). Here, we report that TMCO1 is required for the normal development of CC through sustaining Ca2+ homeostasis. Tmco1-/- mice exhibit severe agenesis of CC with stalled white matter fiber bundles failing to pass across the midline. Mechanistically, the excessive Ca2+ signals caused by TMCO1 deficiency result in upregulation of FGFs and over-activation of ERK, leading to an excess of glial cell migration and overpopulated midline glia cells in the indusium griseum which secretes Slit2 to repulse extension of the neural fiber bundles before crossing the midline. Supportingly, using the clinical MEK inhibitors to attenuate the over-activated FGF/ERK signaling can significantly improve the CC formation in Tmco1-/- brains. Our findings not only unravel the underlying mechanism of abnormal CC in TMCO1 defect syndrome, but also offer an attractive prevention strategy to relieve the related agenesis of CC in patients.

Proteomic analysis of differential anther development from sterile/fertile lines in Capsicum annuum L.

Background: Pepper (Capsicum annuum L.) is a major cash crop throughout the world. Male sterility is an important characteristic in crop species that leads to a failure to produce functional pollen, and it has crucial roles in agricultural breeding and the utilization of heterosis. Objectives: In this study, we identified many crucial factors and important components in metabolic pathways in anther and pollen development, and elucidated the molecular mechanism related to pollen abortion in pepper. Methods: Pepper pollen was observed at different stages to detect the characteristics associated with male sterility and fertility. The phytohormone and oxidoreductase activities were detected in spectrophotometric and redox reaction assays, respectively. Proteins were extracted from male sterile and fertile pepper lines, and identified by TMT/iTRAQ (tandem mass tags/isobaric tags for relative and absolute quantitation) and LC-MS/MS (liquid chromatograph-mass spectrometer) analysis. Differentially abundant proteins (DAPs) were analyzed based on Gene Ontology annotations and the Kyoto Encyclopedia of Genes and Genomes database according to |fold change)| > 1.3 and P value < 0.05. DAPs were quantified in the meiosis, tetrad, and binucleate stages by parallel reaction monitoring (PRM). Results: In this study, we screened and identified one male sterile pepper line with abnormal cytological characteristics in terms of pollen development. The peroxidase and catalase enzyme activities were significantly reduced and increased, respectively, in the male sterile line compared with the male fertile line. Phytohormone analysis demonstrated that the gibberellin, jasmonic acid, and auxin contents changed by different extents in the male sterile pepper line. Proteome analysis screened 1,645 DAPs in six clusters, which were mainly associated with the chloroplast and cytoplasm based on their similar expression levels. According to proteome analysis, 45 DAPs were quantitatively identified in the meiosis, tetrad, and binucleate stages by PRM, which were related to monoterpenoid biosynthesis, and starch and sucrose metabolism pathways. Conclusions: We screened 1,645 DAPs by proteomic analysis and 45 DAPs were related to anther and pollen development in a male sterile pepper line. In addition, the activities of peroxidase and catalase as well as the abundances of phytohormones such as gibberellin, jasmonic acid, and auxin were related to male sterility. The results obtained in this study provide insights into the molecular mechanism responsible for male sterility and fertility in pepper.

BMP4 Exerts Anti-Neurogenic Effect via Inducing Id3 during Aging.

Bone morphogenetic protein (BMP) signaling has been shown to be intimately associated with adult neurogenesis in the subventricular zone (SVZ) and subgranular zone (SGZ). Adult neurogenesis declines in aging rodents and primates. However, the role of BMP signaling in the age-related neurogenesis decline remains elusive and the effect of BMP4 on adult SVZ neurogenesis remains controversial. Here, the expression of BMP4 and its canonical effector phosphorylated-Smad1/5/8 (p-Smad1/5/8) in the murine SVZ and SGZ were found to be increased markedly with age. We identified Id3 as a major target of BMP4 in neuronal stem cells (NSCs) of both neurogenic regions, which exhibited a similar increase during aging. Intracerebroventricular infusion of BMP4 activated Smad1/5/8 phosphorylation and upregulated Id3 expression, which further restrained NeuroD1, leading to attenuated neurogenesis in both neurogenic regions and defective differentiation in the SGZ. Conversely, noggin, a potent inhibitor of BMP4, demonstrated opposing effects. In support of this, BMP4 treatment or lentiviral overexpression of Id3 resulted in decreased NeuroD1 protein levels in NSCs of both neurogenic regions and significantly inhibited neurogenesis. Thus, our findings revealed that the increased BMP4 signaling with age inhibited adult neurogenesis in both SVZ and SGZ, which may be attributed at least in part, to the changes in the Id3-NeuroD1 axis.

Mutations and clinical significance of calcium voltage-gated channel subunit alpha 1E (CACNA1E) in non-small cell lung cancer.

CACNA1E is a gene encoding the ion-conducting α1 subunit of R-type voltage-dependent calcium channels, whose roles in tumorigenesis remain to be determined. We previously showed that CACNA1E was significantly mutated in patients with non-small cell lung cancer (NSCLC) who were long-term exposed to household air pollution, with a mutation rate of 19% (15 of 79 cases). Here we showed that CACNA1E was also mutated in 207 (12.8%) of the 1616 patients with NSCLC in The Cancer Genome Atlas (TCGA) datasets. At mRNA and protein levels, CACNA1E was elevated in tumor tissues compared to counterpart non-tumoral lung tissues in NSCLCs of the public datasets and our settings, and its expression level was inversely associated with clinical outcome of the patients. Overexpression of wild type (WT) or A275S or R249G mutant CACNA1E transcripts promoted NSCLC cell proliferation with activation of epidermal growth factor receptor (EGFR) signaling pathway, whereas knockdown of this gene exerted inhibitory effects on NSCLC cells in vitro and in vivo. CACNA1E increased current density and Ca2+ entrance, whereas calcium channel blockers inhibited NSCLC cell proliferation. These data indicate that CACNA1E is required for NSCLC cell proliferation, and blockade of this oncoprotein may have therapeutic potentials for this deadly disease.

Coevolution between simple sequence repeats (SSRs) and virus genome size.

BACKGROUND: Relationship between the level of repetitiveness in genomic sequence and genome size has been investigated by making use of complete prokaryotic and eukaryotic genomes, but relevant studies have been rarely made in virus genomes. RESULTS: In this study, a total of 257 viruses were examined, which cover 90% of genera. The results showed that simple sequence repeats (SSRs) is strongly, positively and significantly correlated with genome size. Certain repeat class is distributed in a certain range of genome sequence length. Mono-, di- and tri- repeats are widely distributed in all virus genomes, tetra- SSRs as a common component consist in genomes which more than 100 kb in size; in the range of genome < 100 kb, genomes containing penta- and hexa- SSRs are not more than 50%. Principal components analysis (PCA) indicated that dinucleotide repeat affects the differences of SSRs most strongly among virus genomes. Results showed that SSRs tend to accumulate in larger virus genomes; and the longer genome sequence, the longer repeat units. CONCLUSIONS: We conducted this research standing on the height of the whole virus. We concluded that genome size is an important factor in affecting the occurrence of SSRs; hosts are also responsible for the variances of SSRs content to a certain degree.

High GC content of simple sequence repeats in Herpes simplex virus type 1 genome.

The presence, locations and composition of simple sequence repeats (SSRs) in Herpes simplex virus type 1 (HSV-1) genome were extracted and analyzed by using the software Imperfect Microsatellite Extractor (IMEx). There were 663 mon-, 502 di-, 184 tri-, 20 tetra-, 4 penta- and 4 hexanucleotide SSRs that were observed in different distribution between coding and noncoding regions in the HSV-1 genome. G/C, GC/CG, and (GGC)(n) were predominant in mononucleotide, dinucletide, trinucleotide repeats respectively. Indeed, the results showed that GC content in simple sequence repeats was notably higher than that in entire HSV-1 genome. Our data might be helpful for studying the pathogenesis, genome structure and evolution of HSV-1.

Microsatellites in different Potyvirus genomes: survey and analysis.

Simple sequence repeats (SSRs) have been extensively used for various genetic and evolutionary studies in eukaryotic and prokaryotic organisms, while few relevant researches have been made in viruses. The Potyvirus is a fine system to study roles and evolution of SSRs in viruses. The densities, relative abundances, compositions and evolutionary inferences of SSRs in 45 different Potyvirus genomes have been analyzed in this study. Results showed that the densities and relative abundances of SSRs are similar in all those Potyvirus genomes. The number of SSRs decreases with an increase in the length of repeat unit. Dinucleotide repeats are the most abundant and followed by trinucleotide repeats, and the numbers of tetra-, penta- and hexanucleotide repeats are very small. Repeats of AC/CA, AG/GA and AAG/GAA predominate, whereas repeats of CG/GC, ATA and CAC are rare. The genome sizes of the Potyvirus species have little influence on the total number and relative abundance of SSRs. Our study suggested that the variety of SSRs may be related to the genome diversity of Potyvirus. Maybe Potyvirus and HIV genomes have the similar evolution mode and parallel evolution level.