Recombinant Cellular Repressor of E1A-Stimulated Genes Protects against Renal Fibrosis in Dahl Salt-Sensitive Rats.

BACKGROUND: Human cellular repressor of E1A-stimulated genes (CREG) is a secreted glycoprotein that attenuates angiotensin II-induced hypertension, alleviates myocardial fibrosis, and improves heart function. However, the role of CREG in high-salt (HS) diet-induced hypertensive nephropathy is unclear. METHODS: To determine the effects and molecular mechanisms of CREG in HS diet-induced hypertensive nephropathy, we established a hypertensive nephropathy animal model in Dahl salt-sensitive (SS) rats fed a HS diet (8% NaCl, n = 20) for 8 weeks. At week 4 of HS loading, these rats were administered recombinant CREG (reCREG; 35 µg/kg·day, n = 5) and saline (n = 5) via subcutaneously implanted pumps and were also administered the vasodilator hydralazine (20 mg/kg·day, n = 5) in drinking water. We used hematoxylin and eosin staining, Masson's trichrome staining, immunohistochemical labeling, western blotting, RT-PCR, and Tunel staining to determine the signaling pathways of CREG in HS diet-induced hypertensive nephropathy. RESULTS: After 8 weeks of HS intake, the Dahl SS rats developed renal dysfunction and severe renal fibrosis associated with reductions of 78 and 67% in CREG expression, respectively, at both mRNA and protein levels in the kidney. Administration of reCREG improved renal function and relieved renal fibrosis. Administration of CREG also inhibited monocyte infiltration and reduced apoptosis in the kidney cells. CREG overexpression upregulated forkhead box P1 expression and inhibited the transforming growth factor-ß1 signaling pathway. CONCLUSION: Our study shows that CREG protected the kidney against HS-diet-induced renal damage and provides new insights into the mechanisms underlying kidney injury.

[The principle of dRNA-seq and its applications in prokaryotic tran-scriptome analyses].

The genomic and transcriptomic studies have been greatly accelerated by the next-generation sequencing technology. Currently, there are two main methods in transcriptomic studies, namely, Tiling microarray and RNA-seq. Comparatively, because of its overwhelming superiority in transcript coverage and resolution, as well as decrease of costs, RNA-seq has been employed in transcriptome analyses by an increasing number of research institutes. According to the mRNA enrichment or rRNA depletion methods, RNA-seq can be performed in six ways. Among them, dRNA-seq can descriminate the original transcripts from the processed RNAs based on a differential exonuclease treatment. This kind of method has been broadly applied in studies of prokaryotic transcriptional start sites, small regulatory RNAs, promoters and operons, etc. Here, we reviewed the detailed principle and technical process of dRNA-seq and its applications in prokaryotic transcriptome analyses. Besides, we also summarized the advantages and limitations of dRNA-seq at present stage, and then gave our perspective of its future development and potential applications, expecting to present useful references for civil researchers in related fields.

α-Glucosidase Inhibitory Activities and the Interaction Mechanism of Novel Spiro-Flavoalkaloids from YingDe Green Tea.

Flavoalkaloids are a unique class of compounds in tea, most of which have an N-ethyl-2-pyrrolidinone moiety substituted at the A ring of a catechin skeleton. 1-Ethyl-5-hydroxy-pyrrolidone, a decomposed product of theanine, was supposed to be the key intermediate to form tea flavoalkaloids. However, we have also detected another possible theanine intermediate, 1-ethyl-5-oxopyrrolidine-2-carboxylic acid, and speculated if there are related conjugated catechins. Herein, four novel spiro-flavoalkaloids with a spiro-γ-lactone structural moiety were isolated from Yingde green tea (Camellia sinensis var. assamica) in our continuing exploration of new chemical constituents from tea. The structures of the new compounds, spiro-flavoalkaloids A-D (1-4), were further elucidated by extensive nuclear magnetic resonance (NMR) spectroscopy together with the calculated 13C NMR, IR, UV-vis, high-resolution mass, optical rotation, experimental, and calculated circular dichroism spectra. We also provided an alternative pathway to produce these novel spiro-flavoalkaloids. Additionally, their α-glucosidase inhibitory activities were determined with IC50 values of 3.34 (1), 5.47 (2), 22.50 (3), and 15.38 (4) µM. Docking results revealed that compounds 1 and 2 mainly interacted with residues ASP-215, ARG-442, ASP-352, GLU-411, HIS-280, ARG-315, and ASN-415 of α-glucosidase through hydrogen bonds. The fluorescence intensity of α-glucosidase could be quenched by compounds 1 and 2 in a static style.

Circulating Soluble ST2 Predicts All-Cause Mortality in Severe Heart Failure Patients with an Implantable Cardioverter Defibrillator.

BACKGROUND: Heart failure (HF) is the terminal stage of all cardiovascular events. Although implantable cardioverter defibrillator (ICD) therapies have reduced mortality among the high-risk HF population, it is necessary to determine whether certain factors can predict mortality even after cardiac device implantation. Growth stimulation expressed gene 2 (ST2) is an emerging biomarker for HF patient stratification in different clinical settings. AIMS: This study aimed to investigate the relationship between baseline soluble ST2 (sST2) levels in serum and the clinical outcomes of high-risk HF patients with device implantation. METHODS: Between January 2017 and August 2018, we prospectively recruited consecutive patients implanted with an ICD for heart failure, with LVEF ≤35% as recommended, and analyzed the basic characteristics, baseline serum sST2, and NT-proBNP levels, with at least 1-year follow-up. All-cause mortality was the primary endpoint. RESULTS: During a 643-day follow-up, all-cause mortality occurred in 16 of 150 patients (10.67%). Incidence of all-cause mortality increased significantly in patients with sST2 levels above 34.98846 ng/ml (16.00% vs. 5.33%, P = 0.034). After adjusting the model (age, gender, device implantation, prevention of sudden death, LVEDD, LVEF, WBC and CLBBB, hsTNT, etiology, and eGFR) and the model combined with NT-proBNP, the risk of all-cause death was increased by 2.5% and 1.9%, respectively, per ng/ml of sST2. The best sST2 cutoff for predicting all-cause death was 43.42671 ng/ml (area under the curve: 0.72, sensitive: 0.69, and specificity: 0.69). Compared to patients with sST2 levels below 43.42671 ng/ml, the risk of all-cause mortality was higher in those with values above the threshold (5.1% vs. 21.2%, P = 0.002). ST2 level ≥43.42671 ng/ml was an independent predictor of all-cause mortality (HR: 3.30 [95% CI 1.02-10.67]). Age (HR: 1.06 [95% CI: 1.01-1.12]) and increased NT-proBNP per 100 (HR: 1.02 [95% CI: 1.01-1.03]) were also associated with all-cause mortality in ICD patients. CONCLUSIONS: sST2 level was associated with risk of all-cause mortality, and a threshold of 43.43 ng/ml showed good distinguishing performance to predict all-cause mortality in patients with severe heart failure, recommended for ICD implantation. Patients with sST2 levels more than 43.42671 ng/ml even after ICD implantation should therefore be monitored carefully.

Large scale preparation, stress analysis, and storage of headspace volatile condensates from Jasminum sambac flowers.

In this study, a large-scale preparation of jasmine floral volatile condensate (FVC) was conducted using fresh flowers without any extraction solvent involvement. Condensate volatile profiles were compared to those of fresh flowers for their scent characteristics and ability to withstand manufacturing and storage. The FVC possessed a typical jasmine flower scent, a similar odor polygon shape and greatly enhanced odor intensity and character odorants linalool, indole, and methyl anthranilate. In late August and September in Fuzhou, China, the ratio of odor activity values for indole/linalool in FVCs was close to that of fresh flowers, indicating that these were suitable local harvest times for FVC preparation. Room temperature storage for 30 months dramatically reduced the abundance of potent odorants and FVC scent intensity, while cold temperature (4 °C) storage was able to maintain FVC clarity and scent intensity. Our findings should be helpful at improving FVC quantity, quality, and storage.

Transcription and regulation of hepatitis B virus genes in host sperm cells.

To investigate whether transcription of hepatitis B virus (HBV) gene occurs in human sperm, total RNA was extracted from sperm of patients with chronic HBV infection (test-1), from donor sperm transfected with a plasmid containing the full-length HBV genome (test-2), and from nontransfected donor sperm (control), used as the template for reverse transcription-polymerase chain reaction (RT-PCR). Positive bands for HBV DNA were observed in the test groups but not in the control. Next, to identify the role of host genes in regulating viral gene transcription in sperm, total RNA was extracted from 2-cell embryos derived from hamster oocytes fertilized in vitro by HBV-transfected (test) or nontransfected (control) human sperm and successively subjected to SMART-PCR, suppression subtractive hybridization, T/A cloning, bacterial amplification, microarray hybridization, sequencing and the Basic Local Alignment Search Tool (BLAST) search to isolate differentially expressed genes. Twenty-nine sequences showing significant identity to five human gene families were identified, with chorionic somatomammotropin hormone 2 (CSH2), eukaryotic translation initiation factor 4 gamma 2 (EIF4G2), pterin-4 alpha-carbinolamine dehydratase 2 (PCBD2), pregnancy-specific beta-1-glycoprotein 4 (PSG4) and titin (TTN) selected to represent target genes. Using real-time quantitative RT-PCR (qRT-PCR), when CSH2 and PCBD2 (or EIF4G2, PSG4 and TTN) were silenced by RNA interference, transcriptional levels of HBV s and x genes significantly decreased (or increased) (P < 0.05). Silencing of a control gene in sperm did not significantly change transcription of HBV s and x genes (P > 0.05). This study provides the first experimental evidence that transcription of HBV genes occurs in human sperm and is regulated by host genes.

Host genes regulate transcription of sperm-introduced hepatitis B virus genes in embryo.

Hepatitis B virus (HBV) can invade the male germline, and sperm-introduced HBV genes could be transcribed in embryo. This study was to explore whether viral gene transcription is regulated by host genes. Embryos were produced by in vitro fertilization of hamster oocytes with human sperm containing the HBV genome. Total RNA extracted from test and control embryos were subjected to SMART-PCR, SSH, microarray hybridization, sequencing and BLAST analysis. Twenty-nine sequences showing significant identity to five human gene families were identified, with CSH2, EIF4G2, PCBD2, PSG4 and TTN selected to represent target genes. Using qRT-PCR, when CSH2 and PCBD2 (or EIF4G2, PSG4 and TTN) were silenced by RNAi, transcriptional levels of HBV s and x genes decreased (or increased). This is the first report that host genes participate in regulation of sperm-introduced HBV gene transcription in embryo, which is critical to prevent negative impact of HBV infection on early embryonic development.

The integrated HIV-1 provirus in patient sperm chromosome and its transfer into the early embryo by fertilization.

Complete understanding of the route of HIV-1 transmission is an important prerequisite for curbing the HIV/AIDS pandemic. So far, the known routes of HIV-1 transmission include sexual contact, needle sharing, puncture, transfusion and mother-to-child transmission. Whether HIV can be vertically transmitted from human sperm to embryo by fertilization is largely undetermined. Direct research on embryo derived from infected human sperm and healthy human ova have been difficult because of ethical issues and problems in the collection of ova. However, the use of inter-specific in vitro fertilization (IVF) between human sperm and hamster ova can avoid both of these problems. Combined with molecular, cytogenetical and immunological techniques such as the preparation of human sperm chromosomes, fluorescent in situ hybridization (FISH), and immunofluorescence assay (IFA), this study mainly explored whether any integrated HIV provirus were present in the chromosomes of infected patients' sperm, and whether that provirus could be transferred into early embryos by fertilization and maintain its function of replication and expression. Evidence showed that HIV-1 nucleic acid was present in the spermatozoa of HIV/AIDS patients, that HIV-1 provirus is present on the patient sperm chromosome, that the integrated provirus could be transferred into early embryo chromosomally integrated by fertilization, and that it could replicate alongside the embryonic genome and subsequently express its protein in the embryo. These findings indicate the possibility of vertical transmission of HIV-1 from the sperm genome to the embryonic genome by fertilization. This study also offers a platform for the research into this new mode of transmission for other viruses, especially sexually transmitted viruses.