Number and Function of Bone-Marrow Derived Angiogenic Cells and Coronary Flow Reserve in Women without Obstructive Coronary Artery Disease: A Substudy of the NHLBI-Sponsored Women's Ischemia Syndrome Evaluation (WISE)

Background

In women with ischemia and no obstructive coronary artery disease, the Women''s Ischemic Syndrome Evaluation (WISE) observed that microvascular coronary dysfunction (MCD) is the best independent predictor of adverse cardiovascular events. Since coronary microvascular tone is regulated in part by endothelium, we hypothesized that circulating endothelial cells (CEC), which reflect endothelial injury, and the number and function of bone-marrow derived angiogenic cells (BMDAC), which could help repair damaged endothelium, may serve as biomarkers for decreased coronary flow reserve (CFR) and MCD.

Methods

We studied 32 women from the WISE cohort. CFR measurements in response to intracoronary adenosine were taken as an index of MCD. We enumerated BMDAC colonies and CEC in peripheral blood samples. BMDAC function was assessed by assay of migration of CD34+ cells toward SDF-1 and measurement of bioavailable nitric oxide (NO). These findings were compared with a healthy reference group and also entered into a multivariable model with CFR as the dependent variable.

Results

Compared with a healthy reference group, women with MCD had lower numbers of BMDAC colonies [16 (0, 81) vs. 24 (14, 88); P = 0.01] and NO [936 (156, 1875) vs. 1168 (668, 1823); P = 0.02]. Multivariable regression analysis showed strong correlation of CFR to the combination of BMDAC colony count and CD34+ cell function (migration and NO) (R² = 0.45; P<0.05).

Conclusions

The BMDAC function and numbers of BMDAC colonies are decreased in symptomatic women with MCD and are independently associated with CFR. These circulating cells may provide mechanistic insights into MCD in women with ischemia.     

IL28B Polymorphism Correlates with Active Hepatitis in Patients with HBeAg-Negative Chronic Hepatitis B

Background & Aims

The clinical relevance of single nucleotide polymorphisms (SNPs) near the IL28B gene is controversial in patients with hepatitis B virus (HBV) infection. This study aimed to investigate the role of viral and host factors, including IL28B genotypes, in the natural course of chronic hepatitis B (CHB).

Methods

The study enrolled consecutive 115 treatment-naive CHB patients. HBV viral loads, genotypes, precore and basal core promotor mutations, serum hepatitis B surface antigen (HBsAg) and interferon-gamma inducible protein 10 (IP-10) levels as well as four SNPs of IL28B were determined. Serial alanine transaminase (ALT) levels in the previous one year before enrollment at an interval of three months were recorded. Factors associated with active hepatitis, defined as persistent ALT >2× upper limit of normal (ULN) or a peak ALT level >5× ULN, were evaluated.

Results

The prevalence of rs8105790 TT, rs12979860 CC, rs8099917 TT, and rs10853728 CC genotypes were 88.3%, 87.4%, 88.4% and 70.9%, respectively. In HBeAg-positive patients (n = 48), HBV viral load correlated with active hepatitis, while in HBeAg-negative patients (n = 67), rs10853728 CC genotype (p = 0.032) and a trend of higher IP-10 levels (p = 0.092) were associated with active hepatitis. In multivariate analysis, high viral load (HBV DNA >10⁸ IU/mL, p = 0.042, odds ratio = 3.946) was significantly associated with HBeAg-positive hepatitis, whereas rs10853728 CC genotype (p = 0.019, odds ratio = 3.927) was the only independent factor associated with active hepatitis in HBeAg-negative population.

Conclusions

HBV viral load and IL28B rs10853728 CC genotype correlated with hepatitis activity in HBeAg-positive and HBeAg-negative CHB, respectively. Both viral and host factors play roles in disease activity during different phases of CHB.     

Acute Mechanical Stretch Promotes eNOS Activation in Venous Endothelial Cells Mainly via PKA and Akt Pathways

In the vasculature, physiological levels of nitric oxide (NO) protect against various stressors, including mechanical stretch. While endothelial NO production in response to various stimuli has been studied extensively, the precise mechanism underlying stretch-induced NO production in venous endothelial cells remains incompletely understood. Using a model of continuous cellular stretch, we found that stretch promoted phosphorylation of endothelial NO synthase (eNOS) at Ser¹¹⁷⁷, Ser⁶³³ and Ser⁶¹⁵ and NO production in human umbilical vein endothelial cells. Although stretch activated the kinases AMPKα, PKA, Akt, and ERK1/2, stretch-induced eNOS activation was only inhibited by kinase-specific inhibitors of PKA and PI3K/Akt, but not of AMPKα and Erk1/2. Similar results were obtained with knockdown by shRNAs targeting the PKA and Akt genes. Furthermore, inhibition of PKA preferentially attenuated eNOS activation in the early phase, while inhibition of the PI3K/Akt pathway reduced eNOS activation in the late phase, suggesting that the PKA and PI3K/Akt pathways play distinct roles in a time-dependent manner. Finally, we investigated the role of these pathways in stretch-induced endothelial exocytosis and leukocyte adhesion. Interestingly, we found that inhibition of the PI3K/Akt pathway increased stretch-induced Weibel-Palade body exocytosis and leukocyte adhesion, while inhibition of the PKA pathway had the opposite effects, suggesting that the exocytosis-promoting effect of PKA overwhelms the inhibitory effect of PKA-mediated NO production. Taken together, the results suggest that PKA and Akt are important regulators of eNOS activation in venous endothelial cells under mechanical stretch, while playing different roles in the regulation of stretch-induced endothelial exocytosis and leukocyte adhesion.     

An efficient protocol for Agrobacterium-mediated genetic transformation of Antirrhinum majus

Snapdragon (Antirrhinum majus L.) is a popular ornamental and model plant species, and the recently released reference genome could greatly boost its utilization in fundamental research. However, the lack of an efficient genetic transformation system is still a major limiting factor for its full application in genetic and molecular studies. In this study, a simple method for quick regeneration and efficient Agrobacterium-mediated transformation of snapdragon was developed. Cotyledon petiole and hypocotyl explants derived from two-week-old seedlings were cultured on MS media supplemented with 2 mg/L zeatin (ZT), 0.2 mg/L 1-naphthaleneacetic acid (NAA), and 2 mg/L AgNO₃, and adventitious shoots were regenerated through organogenesis with an average regeneration of 48.00% and 41.33%, respectively. By contrast, the regeneration frequency was only 22.67% for cotyledon petiole and 25.67% for hypocotyl explants in the absence of AgNO₃. Moreover, the application of AgNO₃ promoted indirect shoot organogenesis, while direct shoot organogenesis occurred in the absence of AgNO₃ from both hypocotyl or cotyledon petiole explants. Agrobacterium-mediated genetic transformation systems were developed with this high-efficient regeneration system. The transformation efficiency has been improved from 0 to 1% through the direct shoot organogenesis to 3 to 4% via the indirect shoot organogenesis. This efficient regeneration and genetic transformation method could be important for future use of snapdragon as a model plant to address some fundamental questions which are hard to be solved by using other model plant species, and to accelerate the breeding process through CRISPR/Cas9 genome editing.

     

Combined molecular and morphological data provide insights into the evolution and classification of Chilocorini ladybirds (Coleoptera: Coccinellidae)

Ladybirds of the cosmopolitan tribe Chilocorini prey mainly on coccids and include several important biocontrol agents. The phylogenetic relationships of Chilocorini are poorly known. In this paper, we provide a phylogenetic reconstruction of Chilocorini containing all 27 genera based on five molecular markers and 86 adult morphological characters. Morphological character states were mapped on the combined data tree from Bayesian inference to analyse morphological traits of each genus. Sixteen morphological characters were selected to reconstruct the ancestral states using maximum parsimony and maximum likelihood methods. Divergence times were estimated based on the relaxed molecular clock approach. Our results indicate that Chilocorini, excluding Chilocorellus Miyatake, is monophyletic and closely related to Plotinini. The crown group Chilocorini was estimated to date back to the Middle Cretaceous. Anisorcus Crotch, Egius Mulsant, Phaenochilus Weise and Simmondsius Ahmad & Ghani are synonymized here with Chilocorus Leach ( syn.n. ). The genus Chilocorellus is excluded from Chilocorini. The split of current genera was estimated to have occurred during the Middle Paleogene to Late Paleogene.     

Melatonin protects against defects induced by malathion during porcine oocyte maturation

Malathion (MAL) is a common organophosphorus pesticide and affects both animal and human reproduction. However, the mechanisms regarding how MAL affects the mammalian oocyte quality and how to prevent it have not been fully investigated. In this study, we used porcine oocyte as a model and proved that MAL impaired porcine oocyte quality in a dose-dependent manner during maturation. MAL decreased the first polar body extrusion, disrupted spindle assembly and chromosome alignment, impaired cortical granules (CGs) distribution, and increased reactive oxygen species (ROS) level in oocytes. RNA-seq analysis showed that MAL exposure altered the expression of 2,917 genes in the porcine maturated oocytes and most genes were related to ROS, the lipid droplet process, and the energy supplement. Nevertheless, these defects could be remarkably ameliorated by adding melatonin (MLT) into the oocyte maturation medium. MLT increased oocyte maturation rate and decreased the abnormities of spindle assembly, CGs distribution and ROS accumulation in MAL-exposed porcine oocytes. More important, MLT upregulated the expression of genes related to lipid droplet metabolism (PPARγ and PLIN2), decreased lipid droplet size and lipid peroxidation in MAL-exposed porcine oocytes. Finally, we found that MLT increased the blastocysts formation and the cell numbers of blastocysts in MAL-exposed porcine oocytes after parthenogenetic activation, which was mediated by reduction of ROS levels and maintaining lipid droplet metabolism. Taken together, our results revealed that MLT had a protective action against MAL-induced deterioration of porcine oocyte quality.     

Integrated bioinformatics analysis revealed the regulation of angiogenesis by tumor cells in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer mortality, metastasis accounts for most of the cases. Angiogenesis plays an important role in cancer metastasis, but how tumor cells affect the function of endothelial cells by dictating their microRNA (miRNA) expression remains largely unknown.Differentially expressed miRNAs (DEMs) were identified through dataset downloaded from the Gene Expression Omnibus (GEO) database and analyzed by GEO2R. We then used online tools to obtain potential targets of candidate miRNAs and functional enrichment analysis, as well as the protein-protein interaction (PPI). Finally, the function of miR-302c-3p was validated through in vitro assay.In the current study, we found that HCC cells altered miRNA expression profiles of human umbilical vein endothelial cells (HUVECs) and miR-302c-3p was the most down-regulated miRNA in HUVECs when they were co-cultured with HCC-LM3 cells. Functional enrichment analysis of the candidate targets revealed that these genes were involved in epigenetic regulation of gene expression, in particular, cytosine methylation. In addition, PPI network demonstrated distinct roles of genes targeted by miR-302c-3p. Importantly, inhibition of angiogenesis, migration and permeability by the most down-regulated miR-302c-3p in HUVECs was confirmed in vitro. These findings brought us novel insight into the regulation of angiogenesis by HCC cells and provided potential targets for the development of therapeutic strategies.     

hABCF3, a TPD52L2 interacting partner, enhances the proliferation of human liver cancer cell lines in vitro

In the present study, we characterized an evolutionarily conserved non-transmembrane ATP-binding cassette protein: hABCF3. Subcellular immunofluorescence staining demonstrated that hABCF3 localizes preferentially in cytoplasm, unlike its paralog protein hABCF1, which localizes in both cytoplasm and nucleus. Quantitative realtime PCR analysis revealed that hABCF3 is expressed in all tissues examined, with high expression level in heart, liver, and pancreas. Interestingly, ectopic hABCF3 promoted proliferation of human liver cancer cell lines. Moreover, knock down of hABCF3 protein expression by siRNA inhibited cell proliferation. In addition, we identified TPD52L2 (Tumor Protein D52-like 2) as a hABCF3 interacting protein via yeast two-hybrid. This interaction was further confirmed by in vivo co-immunoprecipitation and co-localization assays. Furthermore, we identified the interactional region of hABCF3 to be the first 200 amino acids uncharacterized region. Notably, the truncated version of hABCF3, which lacks the TPD52L2 binding region, remarkably impaired hABCF3-mediated cell proliferation. Taken together, these findings suggest that hABCF3 positively regulates cell proliferation, at least partially through the interaction with a tumor protein D52 protein family member: TPD52L2.     

Reproductive biology of Oxygymnocypris stewartii in the Yarlung Zangbo River in Tibet, China

We determined the gonadal histology, reproductive characteristics and implications for management of Oxygymnocypris stewartii from individuals collected in the Yarlung Zangbo River. Based on the analyses of gonad development and the size distribution of oocytes, O. stewartii spawns just once each year. Peak spawning occurred between late March and early April, when water temperature exceeded 5°C. The standard lengths and the ages at 50 % maturity for males and females were 273 mm and 357 mm, and 5.1 year and 7.3 years, respectively. The mean fecundity of 34211 and mean relative fecundity of 25.4 eggs per gram of fish body weight suggest that O. stewartii might be especially vulnerable to exploitation.     

66 Architectural role of HMO1 in bending,bridging, and compacting DNA

HMO1 proteins are abundant Saccharomyces cerevisiae (yeast) High Mobility Group Box (HMGB) protein (Kamau, Bauerla & Grove, 2004). HMGB proteins are nuclear proteins which are known to be architectural proteins (Travers, 2003). HMO1 possesses two HMGB box domains. It has been reported that double box HMGB proteins induce strong bends upon binding to DNA. It is also believed that they play an essential role in reorganizing chromatin and, therefore, are likely to be involved in gene activation. To characterize DNA binding we combine single molecule stretching experiments and AFM imaging of HMO1 proteins bound to DNA. By stretching DNA bound to HMO1, we determine the dissociation constant, measure protein induced average DNA bending angles, and determine the rate at which torsional constraint of the DNA is released by the protein. To further investigate the local nature of the binding, AFM images of HMO1-DNA complexes are imaged, and we probe the behavior of these complexes as a function of protein concentration. The results show that at lower concentrations, HMO1 preferentially binds to the ends of the double helix and links to the separate DNA strands. At higher concentrations HMO1 induces formation of a complex network that reorganizes DNA. Although HMG nuclear proteins are under intense investigation, little is known about HMO1. Our studies suggest that HMO1 proteins may facilitate interactions between multiple DNA molecules.