Pro-angiogenic effect of exosomal microRNA-103a in mice with rheumatoid arthritis via the downregulation of hepatocyte nuclear factor 4 alpha and activation of the JAK/STAT3 signaling pathway

Rheumatoid arthritis (RA) is characterized by inflammation of the synovial membrane, accompanied by hyperplasia and neo-angiogenesis, which promote local inflammation. Macrophage-derived exosomes have been reported to enhance inflammation and the immune response. In the present study, we identified a novel exosomal microRNA (miR)-103a, which aids in the regulation of inflammation and angiogenesis in mice with RA, and attempted to identify the underlying mechanism. Initially, a mouse model of RA was established. Thereafter, exosomes were isolated from macrophage RAW264.7 cells and evaluated through transmission electron microscopy and nanoparticle tracking analysis. After prediction and verification of the target genes of miR-103a, RT-qPCR was used to assess miR-103a and HNF4A expression in mice with RA. High expression of miR-103a and low expression of HNF4A were observed in mice with RA, thus, miR-103a was found to target and downregulate HNF4A. Exosomal miR-103a promoted inflammation and angiogenesis in mice with RA which was accompanied by an increase in the levels of factors associated with inflammation and angiogenesis. However, an opposite trend was observed upon HNF4A elevation. Exosomal miR-103a was also found to activate the JAK/STAT3 signaling pathway. In conclusion, exosomal miR-103a inhibited the expression of HNF4A to activate the JAK/STAT3 signaling pathway, thereby exacerbating RA in mice.

[Impact of the COVID-19 epidemic on anxiety among the elderly in community]

Objective: To compare the prevalence of anxiety among old people before and during the COVID-19 epidemic in China, and to provide scientific evidence for psychological intervention of the elderly during public health emergencies. Methods: In 2019, the National Psychological Care Project for the Elderly was launched, covering 818 communities across the country, and 188 407 subjects received psychological assessment. In April and May 2020, a convenient sample of 6 467 aged 65 and above subjects were followed up on the anxiety status and its influencing factors during the epidemic period by using structurized questionnaire. Data collection and management were carried out using the national elderly psychological care project data collection platform. McNemar test was used to compare the difference of the prevalence of anxiety among elderly before (October 2019 to January 23, 2020) and during the epidemic (April-May 2020). The difference of the prevalence of anxiety among elderly with different characteristics was compared by chi square test. The influencing factors of anxiety before and during the epidemic situation were analyzed by multivariate logistic regression model. Results: The prevalence of anxiety symptoms in the elderly population was 4.95% (95%CI: 4.42%-5.48%) before the outbreak of COVID-19, and 10.10% (95%CI: 9.36%-10.83%) during the epidemic which was twice as high as before the outbreak. The difference was statistically significant (P<0.05). Multivariate logistic regression analysis showed that the risk factors of anxiety symptoms before the outbreak were with one underlying disease (OR=1.57, 95%CI: 1.05-2.37), with two or more underlying diseases (OR=3.10, 95%CI: 2.13-4.51), and the protective factors were with hobbies, good relationship between children, good relationship with spouse, positive aging attitude and good psychological resilience (all P<0.05). The risk factors of developing anxiety symptoms during the epidemic were living in rural areas (OR=1.77, 95%CI: 1.42-2.20), participating in social activities regularly (OR=1.23, 95%CI: 1.02-1.48), having a good relationship with friends (OR=1.42, 95%CI: 1.11-1.82) and were quarantined or people around were quarantined for medical observation (OR=2.80, 95% CI: 1.90-4.13). Conclusion: The COVID-19 epidemic leads to a double increase in anxiety among the elderly. We should pay more attention to the psychological state of the elderly in rural area and who is being quarantined or people around being quarantined for medical observation.

[Gastric adenocarcinoma of the fundic gland type: clinicopathological analysis of six cases]

Objective: To investigate the clinicopathological characteristics of gastric adenocarcinoma of the fundic gland(GA-FG). Methods: A total of 6 patients with GA-FG admitted from January 2014 to May 2019 were identified at Shanghai Songjiang District Central Hospital.Analyzed endoscopic findings, pathological characteristics and immunohistochemical staining of the lesions and reviewed relevant literatures. Results: Among the 6 patients, 3 were male, 3 were female, and the mean age was 66 years. The most common clinical presentation was epigastric discomfort. Gastroscopic examination revealed an elevated or flat lesion in the body of the stomach, with a diameter of 0.4 to 1.0 cm. Histopathologically, they mainly composed of main cells, but there were also scattered parietal cells, arranged in an irregular tubular or cord-like structure, and formed anastomosis branches. The tumor cells were immunohistochemically positive for MUC6 and pepsinogen 1. Conclusions: GA-FG is a rare variant of well-differentiated adenocarcinoma. It is important to understand its clinical features and histological morphology for more accurate diagnosis.

Nanoarchitecture and dynamics of the mouse enteric glycocalyx examined by freeze-etching electron tomography and intravital microscopy

The glycocalyx is a highly hydrated, glycoprotein-rich coat shrouding many eukaryotic and prokaryotic cells. The intestinal epithelial glycocalyx, comprising glycosylated transmembrane mucins, is part of the primary host-microbe interface and is essential for nutrient absorption. Its disruption has been implicated in numerous gastrointestinal diseases. Yet, due to challenges in preserving and visualizing its native organization, glycocalyx structure-function relationships remain unclear. Here, we characterize the nanoarchitecture of the murine enteric glycocalyx using freeze-etching and electron tomography. Micrometer-long mucin filaments emerge from microvillar-tips and, through zigzagged lateral interactions form a three-dimensional columnar network with a 30 nm mesh. Filament-termini converge into globular structures ~30 nm apart that are liquid-crystalline packed within a single plane. Finally, we assess glycocalyx deformability and porosity using intravital microscopy. We argue that the columnar network architecture and the liquid-crystalline packing of the filament termini allow the glycocalyx to function as a deformable size-exclusion filter of luminal contents.

Sun, Krystofiak et al. show the nanoarchitecture of the murine enteric glycocalyx, glycoprotein-rich coat covering cells and assess its porosity and deformability in mice, providing a comprehensive structural framework. This study suggests that the glycocalyx may function as a deformable size-exclusion filter of luminal contents.

[Impacts of airborne particulate matter and its components on respiratory system health]

Nowadays, particulate air pollution has been a global environmental problem. Numerous studies has shown that long-term exposure to high level of airborne particulate matter (PM) can damage human health. Respiratory system, as a direct portal to contact with particulate matter, can be more susceptible to airborne particulates. Summarizing latest five-year epidemiological research, the present review is focused on the effects of PM on respiratory system health in different age groups. In detail, we investigated the harmful effect of PM, or its components on three common respiratory diseases, including lung function decline, chronic obstructive pulmonary disease (COPD) and asthma. The result showed that, to a certain degree, PM could induce the decline of lung function, the development and the exacerbation of COPD and asthma by oxidative stress and inflammatory reaction. And it may prompt that exposure to PM can be an improtant risk factor for the respiratory system health.

Effects of sodium lactate Ringer's injection on transfection of human protein kinase C-α antisense oligonucleotide in A549 lung cancer cells

In the present study, we evaluated the effects of four solutions [Dulbecco's modified Eagle's medium (DMEM), sodium lactate Ringer's injection (SLRI), phosphate-buffered saline (PBS), and NaCl] on the transfection of the human protein kinase C-a antisense oligonucleotide (PKC-a ASO) aprinocarsen in human lung carcinoma A549 cells. Specifically, SLRI, DMEM, PBS, or NaCl were used as the growth solutions for A549 cells, and OPTI-MEM was used as the PKC-a ASO diluent for transfection. Additionally, SLRI, DMEM, PBS, or NaCl were used as both the growth solutions and diluents for transfection. The cell viability and transfection efficiency were determined. The results demonstrated that when SLRI was used as either the growth solution or both the growth solution and diluent for aprinocarsen transfection in A549 cells, the effects were close to the best effects observed with DMEM as the growth solution and OPTI-MEM as the diluent, which supported the transfection of aprinocarsen into the cells. Moreover, SLRI resulted in higher transfection efficiency than those of PBS and NaCl. In in vitro experiments, aprinocarsen effectively induced apoptosis in A549 cells. In conclusion, SLRI may replace PBS or NaCl in clinical trials as a transfection solution readily accepted by the human body. To our knowledge, this is the first report demonstrating the use of SLRI as a transfection solution in lung-cancer cell lines.

Kremen1 regulates mechanosensory hair cell development in the mammalian cochlea and the zebrafish lateral line

Here we present spatio-temporal localization of Kremen1, a transmembrane receptor, in the mammalian cochlea, and investigate its role in the formation of sensory organs in mammal and fish model organisms. We show that Kremen1 is expressed in prosensory cells during cochlear development and in supporting cells of the adult mouse cochlea. Based on this expression pattern, we investigated whether Kremen1 functions to modulate cell fate decisions in the prosensory domain of the developing cochlea. We used gain and loss-of-function experiments to show that Kremen1 is sufficient to bias cells towards supporting cell fate, and is implicated in suppression of hair cell formation. In addition to our findings in the mouse cochlea, we examined the effects of over expression and loss of Kremen1 in the zebrafish lateral line. In agreement with our mouse data, we show that over expression of Kremen1 has a negative effect on the number of mechanosensory cells that form in the zebrafish neuromasts, and that fish lacking Kremen1 protein develop more hair cells per neuromast compared to wild type fish. Collectively, these data support an inhibitory role for Kremen1 in hair cell fate specification.

Hydrogen peroxide enhances the uptake of polyethylenimine/oligonucleotide complexes in A549 cells by activating CaMKII independent of [Ca(2+)]c elevation

Aerosol oligonucleotide therapy has vast potential in pulmonary system diseases. Reactive oxygen species (ROS) play an important role in complex physiological processes such as cell signaling, apoptosis, etc. Therefore, to determine the mechanism of ROS involvement in polyethylenimine/oligonucleotide (PEI/ON) endocytosis in cells, we measured the fluorescence intensities of fluorescein isothiocyanate-labeled ON complexes with PEI and the changes in cytosolic Ca(2+) concentration ([Ca(2+)]c) in A549 cells after hydrogen peroxide (H2O2) stimulation. Results showed that improved uptake of PEI/ON complexes was independent of the rise of [Ca(2+)]c in A549 cells, including the Ca(2+) inflow and the release of Ca(2+) from intracellular stores induced by 500 μM H2O2. However, the enhanced uptake efficiency was almost completely abolished by the calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitor and the microtube depolymerized drug. CaMKII-dependent microtube polymerization may be responsible for the enhanced uptake of PEI/ON complexes in A549 cells under oxidative stress conditions. This study is useful for research aimed at improving aerosol oligonucleotide therapy in pulmonary system diseases.

Secreted factor R-Spondin 2 is involved in refinement of patterning of the mammalian cochlea

BACKGROUND

In the cochlea, patterning of the organ of Corti is tightly regulated to produce a single row of sound-detecting inner hair cells and three rows of outer hair cells, which amplify and refine the signal. The recently identified R-Spondin family of signaling molecules usually act as co-activators of Wnt signaling; it is thought that they regulate turnover of Wnt receptors at the membrane. We sought to test whether R-Spondins function in the developing cochlea.

RESULTS

Expression analysis of all four members of the R-Spondin family showed that only R-Spondin2 (Rspo2) is expressed in the cochlea during development of the sensory epithelium. Examination of an Rspo2(-/-) mouse showed that loss of Rspo2 results in an additional single row of outer hair cells and disruption of peripheral innervation pattern. Addition of Rspo2 recombinant protein to organotypic cochlear cultures resulted in a small but significant decrease in the number of outer hair cells.

CONCLUSIONS

Rspo2 is required to limit the number of outer hair cells to three rows and for optimal arrangement of peripheral nerve fibers. The Rspo2 gain- and loss-of-function studies show that in the ear, Rspo2 function is not consistent with its assigned role as a Wnt potentiator.

The Wnt receptor Ryk plays a role in mammalian planar cell polarity signaling

Wnts are essential for a wide range of developmental processes, including cell growth, division, and differentiation. Some of these processes signal via the planar cell polarity (PCP) pathway, which is a β-catenin-independent Wnt signaling pathway. Previous studies have shown that Ryk, a member of the receptor tyrosine kinase family, can bind to Wnts. Ryk is required for normal axon guidance and neuronal differentiation during development. Here, we demonstrate that mammalian Ryk interacts with the Wnt/PCP pathway. In vitro analysis showed that the Wnt inhibitory factor domain of Ryk was necessary for Wnt binding. Detailed analysis of two vertebrate model organisms showed Ryk phenotypes consistent with PCP signaling. In zebrafish, gene knockdown using morpholinos revealed a genetic interaction between Ryk and Wnt11 during the PCP pathway-regulated process of embryo convergent extension. Ryk-deficient mouse embryos displayed disrupted polarity of stereociliary hair cells in the cochlea, a characteristic of disturbed PCP signaling. This PCP defect was also observed in mouse embryos that were double heterozygotes for Ryk and Looptail (containing a mutation in the core Wnt/PCP pathway gene Vangl2) but not in either of the single heterozygotes, suggesting a genetic interaction between Ryk and Vangl2. Co-immunoprecipitation studies demonstrated that RYK and VANGL2 proteins form a complex, whereas RYK also activated RhoA, a downstream effector of PCP signaling. Overall, our data suggest an important role for Ryk in Wnt/planar cell polarity signaling during vertebrate development via the Vangl2 signaling pathway, as demonstrated in the mouse cochlea.

A family-based and case-control association study of the NOTCH4 gene and schizophrenia

Recently a strong positive association between schizophrenia and Notch4 has been reported. Both individual markers and haplotypes showed association with the disease, with five markers (three microsatellites and two SNPs) being tested. In order to test this finding we genotyped these markers in the Han Chinese population using a sample of 544 cases and 621 controls as well as >300 trios. Analysis of allele, genotype and haplotype frequencies in both samples showed no association between the markers and the disease. Our results would indicate that a significant role for the Notch4 gene in schizophrenia can be ruled out in the Han Chinese. However, similar studies are necessary in the Caucasian population as linkage disequilibrium arrangements and founder effects may differ between these two populations.

Binding characteristics of M and L isoantibodies to high and low potassium sheep red cells

Binding of highly purified 125I labeled M and L antibodies, both belonging to the immunoglobulin G class, was studied in high potassium (HK) and low potassium (LK) sheep red cells. Anti-M and anti-L bound specifically to M and L antigen positive HK and LK red cells, respectively. Nonspecific binding was higher for anti-L to HK cells than for anti-M to LK cells. Once bound, the M and L antibodies were capable of inducing complement dependent immune hemolysis. Only 75-100 and 500-750 molecules of anti-M and anti-L immunoglobulins were required to hemolyze 50% of HK (MM) and LK (LL) red cells, respectively, suggesting that the M and L antigens may be clustered on the surfaces of these cells. Equilibrium binding studies revealed that the maximum number of M sites is 3-6 x 10(3) in HK (MM) and 1.5-4 x 10(3) in LK (LM) cells, respectively. In comparison, the number of L antigens is slightly lower in LK cells, about 1.2-1.8 x 10(3) in LL and less in LM(LK) red cells. The number of M and L antigens, therefore, is more than an order of magnitude larger than that of the Na+K+ pumps measured previously in these cells by 3H-ouabain binding, thus precluding a quantitative correlation between M and L antigens and the Na+K+ pumps different in the three genetic types of sheep red cells. The binding affinities of both anti-M and anti-L could not be described by a single equilibrium dissociation constant indicating heterogeneous antibody populations and /or variability in the antigenic sets of individual HK or LK cells. The pronounced heterogeneity of antigens and/or antibodies in both the M and L systems was reflected in the antibody association kinetics, which also exhibited a remarkable temperature dependence. The data suggest that the correlation between the M and L antigens and the Na+K+ pump molecules is more complex than that in goat red cells previously reported by others.