Maternal immune activation mediated prenatal chronic stress induces Th17/Treg cell imbalance may relate to the PI3K/Akt/NF-κB signaling pathway in offspring rats.

Maternal immune activation (MIA), defined as elevated levels of inflammatory markers beyond the normal range, can occur due to psychological stress, infection, and other disruptions during pregnancy. MIA affects the immune system development in offspring and increases the risk of immune-related disorders. Limited studies have investigated the effects of prenatal stress on offspring's immune system. In this study, pregnant rats were exposed to chronic unpredictable mild stress (CUMS) during pregnancy, involving seven different stressors. We examined the impact of prenatal stress stimuli on the offspring's immune system and observed activation of the PI3K/Akt/NF-κB signaling pathway, resulting in an imbalance of Th17/Treg cells in the offspring's spleen. Our findings revealed increased plasma levels of corticosterone, IL-1ß, and IL-6 in female rats exposed to prenatal stress, as well as elevated serum levels of IL-6 and TNF-α in the offspring. Furthermore, we identified a correlation between cytokine levels in female rats and their offspring. Transcriptome sequencing and qPCR experiments indicated differentially expressed mRNAs in offspring exposed to prenatal stress, which may contribute to the imbalance of Th17/Treg cells through the activation of the Gng3-related PI3K/Akt/NF-κB pathway.

Effects of biodegradable biomedical porous MnO2 nanoparticles on blood components and functions.

In recent years, manganese dioxide (MnO2) nanoparticles with unique physicochemical properties have been widely used in many biomedical fields, such as biosensors, contrast agents, tumor therapy, and drug delivery. From these applications, MnO2 nanoparticles have great clinical translation potential. However, by contrast, the in vitro and in vivo biosafety of MnO2 nanoparticles have been deeply and thoroughly clarified for the clinical translation, which hinders their clinical applications. In this work, we deeply investigated the blood safety of MnO2 nanoparticles by conducting a series of in vitro and in vivo experiments. These included the effects of MnO2 nanoparticles on morphology of red blood cells, activation of platelets, coagulation functions, and toxicity of key organs. The obtained results show that these effects displayed a concentration-dependent manner of MnO2 nanoparticles. Different safe concentration ranges could be found in the different experimental index. This study provides important guidance for the specific biomedical applications of MnO2 nanoparticles, greatly accelerating their laboratory development and clinical translation.

Activation of PGE2/EP2 and PGE2/EP4 signaling pathways positively regulate the level of PD-1 in infiltrating CD8+ T cells in patients with lung cancer.

The present study aimed to identify the level of programmed death-1 (PD-1) expression in infiltrating cluster of differentiation (CD)4+ and CD8+ T cells isolated from lung cancer tissues, and investigated whether the level of PD-1 expression may be directly regulated by lung cancer cells via prostaglandin E2 (PGE2)-associated signaling pathways in patients with lung cancer. A total of 75 patients with lung cancer were enrolled in the present study. The percentage of infiltrating CD4+ and CD8+ T cells was determined by flow cytometry. ELISA was performed to evaluate the concentration of PGE2 in lung cancer tissue homogenate. The correlation between PGE2 and PD-1 expression levels in CD8+ T cells was assessed by Spearman's rank correlation test. The expression levels of PD-1 and PGE2 receptors were determined by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. The level of PD-1 expression in infiltrating CD8+ T cells was gradually increased as the stage of lung cancer increased. The level of PD-1 expression was also positively associated with the concentration of PGE2 in lung cancer tissues. Furthermore, the level of PD-1 expression was closely associated with the PGE2/EP2 and PGE2/EP4 signaling pathways. The activation of PGE2-associated EP2- and EP4-pathways may positively regulate the level of PD-1 in infiltrating CD8+ T cells, which results in immune tolerance in the lung cancer microenvironment.

Expression of programmed cell death1 in T follicular helper cells is regulated by prostaglandin E2 secreted by HBV-infected HepG2.2.1.5 cells.

The present study aimed to investigate the distribution of T follicular helper (Tfh)-cell subsets in patients with hepatitis B virus (HBV) and determine the underlying mechanism of HBV regulation of Tfh cells. The frequency of peripheral blood Tfh subsets was analyzed using flow cytometry. The expression level of programmed cell death­1 (PD­1) and prostaglandin E2 (PGE2) was quantified using reverse transcription­quantitative polymerase chain reaction and western blotting. The PGE2 level in culture supernatant was detected using enzyme­linked immunosorbent assay. A Transwell chamber was used to co­culture Tfh cells with HepG2 and HepG2.2.1.5. The percentage of inducible T­cell costimulator (ICOS)+ and total Tfh cells was high at the immune activation (IA) group; however, it was reduced in the immune tolerance (IT), responders with HBsAg seroconversion (RP) and healthy control (HC) groups. The percentage of PD­1+ Tfh cells was significantly higher in IA and IT compared with RP and HC. The ratio of PD­1+/total Tfh cells was positively correlated with the load of HBV DNA; therefore, this ratio may act as an indicator for HBV replication. The expression level of PD­1 in Tfh cells was higher in the HepG2.2.1.5 co­cultured group compared with the HepG2 group, this may be due to the high PGE2 expression level in HBV­infected HepG2.2.1.5 cells. The findings of the present study revealed an imbalanced distribution of PD­1+ Tfh cells in patients with HBV at different immune phases. Additionally, HBV may upregulate the expression of PD­1 in Tfh cells by promoting HepG2.2.1.5 to secret PGE2. Identifying the effect of HBV on Tfh­cell subsets is crucial for improving immuno-based therapy for HBV.

Role of Mir-155 in Controlling HIF-1α Level and Promoting Endothelial Cell Maturation.

Stem-cell-based therapy for cardiovascular disease, especially ischemic heart disease (IHD), is a promising approach to facilitating neovascularization through the migration of stem cells to the ischemic site and their subsequent differentiation into endothelial cells (ECs). Hypoxia is a chief feature of IHD and the stem cell niche. However, whether hypoxia promotes stem cell differentiation into ECs or causes them to retain their stemness is controversial. Here, the differentiation of pluripotent stem cells (iPSCs) into endothelial cells (ECs) was induced under hypoxia. Though the angiogenic capability and angiogenesis-related autocrine/paracrine factors of the ECs were improved under hypoxia, the level of hypoxia inducible factor 1α (HIF-1α) was nonetheless found to be restricted along with the EC differentiation. The down-regulation of HIF-1α was found to have been caused by VEGF-induced microRNA-155 (miR-155). Moreover, miR-155 was also found to enhance the angiogenic capability of induced ECs by targeting E2F2 transcription factor. Hence, miR-155 not only contributes to controlling HIF-1α expression under hypoxia but also promotes angiogenesis, which is a key feature of mature ECs. Revealing the real role of hypoxia and clarifying the function of miR-155 in EC differentiation may facilitate improvement of angiogenic gene- and stem-cell-based therapies for ischemic heart disease.

Role of osteoprotegerin and its gene polymorphisms in the occurrence of left ventricular hypertrophy in essential hypertensive patients.

The aim of the study was to investigate the role of osteoprotegerin (OPG) in left ventricular hypertrophy (LVH) development in patients with essential hypertension (EH). A total of 1092 patients diagnosed with EH were recruited. The LVHs were determined and OPG gene polymorphisms were genotyped. Patients with LVH had a significantly higher mean serum OPG level than those without LVH. The 1181CC genotype carriers had significantly lower risk for LVH compared with GC and GG genotype carriers. The serum OPG level and OPG 1181 G>C polymorphism were found to be independent risk factors for the occurrence of LVH in hypertensive patients. In vitro study shows that OPG overexpression upregulates cell surface size, protein synthesis per cell, and hypertrophy- and fibrosis-related proteins in both cardiomyocytes and cardiac fibroblasts, whereas OPG inhibition can abolish the above-mentioned changes. Consistent with the in vitro data, our in vivo study revealed that the OPG administration induced the LVH in hypertensive rats. This study is the first to report the close association between OPG and LVH development in EH patients and the regulatory effect of OPG on cardiomyocytes and cardiac fibroblasts.

Micromonospora zeae sp. nov., a novel endophytic actinomycete isolated from corn root (Zea mays L.).

A novel actinomycete, designated strain NEAU-gq9(T), was isolated from corn root (Zea mays L.) and characterized using a polyphasic approach. The organism was found to have morphological and chemotaxonomic characteristics typical of the genus Micromonospora. On the basis of 16S rRNA gene sequence similarity studies, strain NEAU-gq9(T) was most closely related to Micromonospora zamorensis CR38(T) (99.3%), Micromonospora jinlongensis NEAU-GRX11(T) (99.2%), Micromonospora saelicesensis Lupac 09(T) (99.2%), Micromonospora chokoriensis 2-19(6)(T) (98.9%), Micromonospora coxensis 2-30-b(28)(T) (98.6%) and Micromonospora lupini Lupac 14N(T) (98.5%). Phylogenetic analysis based on the 16S rRNA gene and gyrB gene demonstrated that strain NEAU-gq9(T) is a member of the genus Micromonospora and supported the closest phylogenetic relationship to M. zamorensis CR38(T), M. jinlongensis NEAU-GRX11(T), M. saelicesensis Lupac 09(T), M. chokoriensis 2-19(6)(T) and M. lupini Lupac 14N(T). A combination of DNA-DNA hybridization, morphological and physiological characteristics indicated that the novel strain could be readily distinguished from the closest phylogenetic relatives. Therefore, it is proposed that strain NEAU-gq9(T) represents a novel species of the genus Micromonospora, for which the name Micromonospora zeae sp. nov. is proposed. The type strain is NEAU-gq9(T) (=CGMCC 4.7092(T)=DSM 45882(T)).

Actinoplanes hulinensis sp. nov., a novel actinomycete isolated from soybean root (Glycine max (L.) Merr).

A novel actinomycete, designated strain NEAU-M9(T), was isolated from soybean root (Glycine max (L.) Merr) and characterized using a polyphasic approach. 16S rRNA gene sequence similarity studies showed that strain NEAU-M9(T) belonged to the genus Actinoplanes, being most closely related to Actinoplanes campanulatus DSM 43148(T) (98.85 %), Actinoplanes capillaceus DSM 44859(T) (98.70 %), Actinoplanes lobatus DSM 43150(T) (98.30 %), Actinoplanes auranticolor DSM 43031(T) (98.23 %) and Actinoplanes sichuanensis 03-723(T) (98.06 %); similarity to other type strains of the genus Actinoplanes ranged from 95.87 to 97.56 %. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that the isolate formed a distinct phyletic line with A. campanulatus DSM 43148(T) and A. capillaceus DSM 44859(T). This branching pattern was also supported by the tree constructed with the maximum-likelihood method. However, the low level of DNA-DNA relatedness allowed the isolate to be differentiated from the above-mentioned two Actinoplanes species. Moreover, strain NEAU-M9(T) could also be distinguished from the most closely related species by morphological, physiological and characteristics. Therefore, it is proposed that strain NEAU-M9(T) represents a novel Actinoplanes species, Actinoplanes hulinensis sp. nov. The type strain of Actinoplanes hulinensis is NEAU-M9(T) (= CGMCC 4.7036(T) = DSM 45728(T)).

MicroRNA alterations in senescent endothelial progenitor cells induced by remnant-like lipoproteins.

BACKGROUND: Remnant-like lipoproteins (RLPs) have been demonstrated to accelerate the onset of endothelial progenitor cells (EPCs) senescence. Recent study has determined that microRNAs (miRNAs) were closely associated with cellular proliferation and senescence. This study aimed to examine whether RLPs lead to an alteration of miRNAs in senescent EPCs. METHODS: RLPs were prepared from plasma samples with immunoaffinity method. After 8 days of culture, EPCs were identified by flow cytometry analysis. Cells were incubated with RLPs for 72 hours. The senescent markers p16INK4a and senescence-associated beta-galactosidase (SA-ß-gal) were detected by Western blotting analysis and ß-gal staining assay, respectively. A human miRNA microarray containing 723 miRNAs was used to detect the expression profile of miRNAs in control and senescent EPCs. The result from the above microarray was qualified by RT-PCR assay. RESULTS: RLPs dose-dependently up-regulated the protein level of p16(INK4a) in EPCs, and RLPs at a concentration of 100 µg/ml induced a significant increase in the percentage of SA-ß-gal-positive EPCs. Of 723 miRNAs, four miRNAs expressed differentially and significantly in RLPs-treated EPCs (P < 0.05), then their changes in expression were validated by real-time RT-PCR. Among them miR-148b and miR-155 were upregulated while miR-574-3p was down-regulated significantly when compared with control (P < 0.01). CONCLUSIONS: RLPs result in the onset of EPCs senescence. Senescent EPCs induced by RLPs exhibit a different profile of miRNAs. These three miR-148b and miR-155 and miR-574-3p reach a significant difference when compared with control, indicating that microRNA might take part in RLPs-induced EPCs senescence.

Expression of interleukin-15 and its receptor on the surface of stimulated human umbilical vein endothelial cells.

Human interleukin-15 (hIL-15) is an important cytokine to activate endothelial cells and can be regulated by many other cytokines. The aim of this study is to examine the ability of interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha) to induce the production of human interleukin-15 (hIL-15) and IL-15 receptor (IL-15Ralpha) by human umbilical vein endothelial cells (HUVECs). The data are summarized as follows: 1. Northern blot revealed that IL-15 mRNA was up-regulated by IFN-gamma and TNF-alpha. 2. Intracellular IL-15 protein was visualized by fluorescence microscopy, whereas the expression of IL-15 on the surface of HUVECs was detected by fluorescence activated cell sorting (FACS), and no detectable IL-15 in the medium was verified by ELISA. 3. IL-15Ralpha was detected on the surface of HUVECs by FACS after IFN-gamma and TNF-alpha stimulation, whereas Western blotting revealed that the elevated expression on surface IL-15Ralpha was not due to the increased protein expression. The conclusion demonstrated from our results is that IFN-gamma and TNF-alpha play an important role in regulating the expression of IL-15 and IL-15Ralpha on the surface of HUVECs.

Remnant-like particles accelerate endothelial progenitor cells senescence and induce cellular dysfunction via an oxidative mechanism.

Remnant-like particles (RLPs) are closely associated with coronary heart disease and can induce endothelial dysfunction through oxidative mechanisms. Many risk factors accelerate the onset of endothelial progenitor cells (EPCs) senescence via increased oxidative stress. In this study, we investigated the effect of RLPs on EPCs senescence and function. RLPs were isolated from postprandial plasma of hypertriglyceridemic patients by use of the immunoaffinity gel mixture of anti-apoA-1 and anti-apoB-100 monoclonal antibodies. Our results show that EPCs became senescent as determined by senescence-associated acidic beta-galactosidase (SA-beta-Gal) staining after ex vivo cultivation without any stimulation. Co-incubation with RLPs accelerated the increase in SA-beta-Gal-positive EPCs. The acceleration of RLPs-induced EPCs senescence occurred dose-dependently with a maximal effect when EPCs were treated with RLPs at 0.10 mg cholesterol/mL (P<0.01). Moreover, RLPs decreased adhesion, migration and proliferation capacities of EPCs as assessed by adherence to fibronectin, modified Boyden chamber technique and MTT assay (P<0.01), respectively. RLPs increased nitrotyrosine staining in EPCs. However, RLPs-induced EPCs senescence and dysfunction were significantly inhibited by pre-treatment of superoxide dismutase (50 U/mL) (P<0.05). Our results provide evidence that RLPs accelerate the onset of EPC senescence via increased oxidative stress, accompanying with the impairment of adhesion, migration and proliferation capacities.

Cyclin-dependent kinase inhibitor p16(INK4a) and telomerase may co-modulate endothelial progenitor cells senescence.

Endothelial cells (ECs) damage is an initial and pivotal step in the formation of atherosclerosis. Endothelial progenitor cells (EPCs), which have been considered as the precursor of ECs, can migrate and home to the site of injured ECs to divide into mature ECs and keep the integrity of the endothelial monolayer. It has been shown that the number and function of EPCs are negatively correlated with various atherosclerotic risk factors. This finding may be explained partly by accelerated senescence of EPCs induced by telomere attrition or shortening owning to oxidative stress and accumulative ROS. However, elevated telomerase activity which extends the telomere cannot lead to cellular immortal in the presence of the cyclin-dependent kinase inhibitor p16(INK4a). Researchers have the opinion that senescence is the balance between the regeneration and cancer. High expression of phosphorylated p16(INK4a), which is caused by oxidative stress and accumulative ROS, can prevent tumor cells from unlimited division and becoming malignant ones by accelerating premalignant cells premature senescence. It has been demonstrated that the expression of p16(INK4a) increases remarkably with age due to oxidative stress and accumulative ROS in some stem and progenitor cells, and regulates these cells age-dependent senescence. It is observed that telomeres shortening exists in these cells. Therefore, it can be hypothesized that p16(INK4a), together with telomerase, may co-modulate EPCs senescence.

Modulation of interleukin-15-induced suppression of human neutrophil apoptosis by TNFalpha.

Human interleukin-15 (IL-15) is a proinflammatory cytokine to suppress neutrophil apoptosis, which is a potential therapeutic agent. The modulatory effect of TNFalpha was investigated in IL-15-induced suppression of human neutrophil apoptosis. TNFalpha was shown to reverse the ability of IL-15 to delay neutrophil apoptosis within certain time course. Moreover, this reverse effect by TNFalpha might be associated with a reduction of the expression of the anti-apoptotic Bcl-Xl protein detected by Western blotting. It is concluded that TNFalpha can be used to modulate IL-15-induced suppression of neutrophil apoptosis within certain time course.