Publications by authors named "Rongrong Jiang"

58 Publications

Prediction of Transporter-Mediated Drug-Drug Interactions and Phenotyping of Hepatobiliary Transporters Involved in the Clearance of E7766, a Novel Macrocycle-Bridged Dinucleotide.

Drug Metab Dispos 2021 Mar 18;49(3):265-275. Epub 2020 Dec 18.

Drug Metabolism and Pharmacokinetics (R.J., V.D., W.G.L., A.H.) and Genetics Guided Dementia Discovery, Eisai Inc, Cambridge, Massachusetts (L.B., D.-S.K.)

E7766 represents a novel class of macrocycle-bridged dinucleotides and is under clinical development for immuno-oncology. In this report, we identified mechanism of systemic clearance E7766 and investigated the hepatobiliary transporters involved in the disposition of E7766 and potential drug interactions of E7766 as a victim of organic anion-transporting polypeptide (OATP) inhibitors. In bile-duct cannulated rats and dogs, E7766 was mainly excreted unchanged in bile (>80%) and to a lesser extent in urine (<20%). Sandwich-cultured human hepatocytes (SCHHs), transfected cells, and vesicles were used to phenotype the hepatobiliary transporters involved in the clearance of E7766. SCHH data showed temperature-dependent uptake of E7766 followed by active biliary secretion. In vitro transport assays using transfected cells and membrane vesicles confirmed that E7766 was a substrate of OATP1B1, OATP1B3, and multidrug resistance-associated protein 2. Phenotyping studies suggested predominant contribution of OATP1B3 over OATP1B1 in the hepatic uptake of E7766. Studies in OATP1B1/1B3 humanized mice showed that plasma exposure of E7766 increased 4.5-fold when coadministered with Rifampicin. Physiologically based pharmacokinetic models built upon two independent bottom-up approaches predicted elevation of E7766 plasma exposure when administered with Rifampicin, a clinical OATP inhibitor. In conclusion, we demonstrate that OATP-mediated hepatic uptake is the major contributor to the clearance of E7766, and inhibition of OATP1B may increase its systemic exposure. Predominant contribution of OATP1B3 in the hepatic uptake of E7766 was observed, suggesting polymorphisms in OATP1B1 would be unlikely to cause variability in the exposure of E7766. SIGNIFICANCE STATEMENT: Understanding the clearance mechanisms of new chemical entities is critical to predicting human pharmacokinetics and drug interactions. A physiologically based pharmacokinetic model that incorporated parameters from mechanistic in vitro and in vivo experiments was used to predict pharmacokinetics and drug interactions of E7766, a novel dinucleotide drug. The findings highlighted here may shed a light on the pharmacokinetic profile and transporter-mediated drug interaction propensity of other dinucleotide drugs.
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http://dx.doi.org/10.1124/dmd.120.000125DOI Listing
March 2021

A clinical pilot study on the safety and efficacy of aerosol inhalation treatment of IFN-κ plus TFF2 in patients with moderate COVID-19.

EClinicalMedicine 2020 Aug 29;25:100478. Epub 2020 Jul 29.

Shanghai Public Health Clinical Center & Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 201508, PR China.

Background: The outbreak of a new coronavirus (SARS-CoV-2) poses a great challenge to global public health. New and effective intervention strategies are urgently needed to combat the disease.

Methods: We conducted an open-label, non-randomized, clinical trial involving moderate COVID-19 patients according to study protocol. Patients were assigned in a 1:2 ratio to receive either aerosol inhalation treatment with IFN-κ and TFF2, every 48 h for three consecutive dosages, in addition to standard treatment (experimental group), or standard treatment alone (control group). The end point was the time to discharge from the hospital. This study is registered with chictr.org.cn, ChiCTR2000030262.

Findings: A total of thirty-three eligible COVID-19 patients were enrolled from February 1, 2020 to April 6, 2020, eleven were assigned to the IFN-κ plus TFF2 group, and twenty-two to the control group. Safety and efficacy were evaluated for both groups. No treatment-associated severe adverse effects (SAE) were observed in the group treated with aerosol inhalation of IFN-κ plus TFF2, and no significant differences in the safety evaluations were observed between experimental and control groups. CT imaging was performed in all patients with the median improvement time of 50 days (IQR 30-90) in the experimental group versus 85 days (IQR 30-170) in the control group (<005). In addition, the experimental group had a significant shorten median time in cough relief (45 days [IQR 20-70]) than the control group did (100 days [IQR 60-210])(<0005), in viral RNA reversion of 60 days (IQR 20-130) in the experimental group vs 9.5 days (IQR 30-230) in the control group ( < 005), and in the median hospitalization stays of 120 days (IQR 7.0-20.0) in the experimental group vs 150 days (IQR 10.0-25.0) in the control group (<0001), respectively.

Interpretation: Aerosol inhalation of IFN-κ plus TFF2 is a safe treatment and is likely to significantly facilitate clinical improvement, including cough relief, CT imaging improvement, and viral RNA reversion, thereby achieves an early release from hospitalization. These data support to explore a scale-up trial with IFN-κ plus TFF2.

Funding: National Major Project for Control and Prevention of Infectious Disease in China, Shanghai Science and Technology Commission, Shanghai Municipal Health Commission.
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http://dx.doi.org/10.1016/j.eclinm.2020.100478DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7388798PMC
August 2020

Overexpression of microRNA-23a-5p induces myocardial infarction by promoting cardiomyocyte apoptosis through inhibited of PI3K/AKT signalling pathway.

Cell Biochem Funct 2020 Dec 9;38(8):1047-1055. Epub 2020 Jun 9.

Department of Cardiothoracic surgery, Huashan Hospital of Fudan University, Shanghai, China.

Myocardial infarction (MI) leads to cardiac remodelling and heart failure. Cardiomyocyte apoptosis is considered a critical pathological phenomenon accompanying MI, but the pathogenesis mechanism remains to be explored. MicroRNAs (miRs), with the identity of negative regulator of gene expression, exist as an important contributor to apoptosis. During the experiment of this study, MI mice models were successfully established and sequencing data showed that the expression of miR-23a-5p was significantly enhanced during MI progression. Further steps were taken and it showed that apoptosis of cardiac cells weakened as miR-23a-5p was downregulated and on the contrary that apoptosis strengthened with the overexpression of miR-23a-5p. To explore its working mechanisms, bioinformatics analysis was conducted by referring to multi-databases to predict the targets of miR-23a-5p. Further analysis suggested that those downstream genes enriched in several pathways, especially in the PI3K/Akt singling pathway. Furthermore, it demonstrated that miR-23a-5p was negatively related to the phosphorylation of PI3K/Akt, which plays a critical role in triggering cell apoptosis during MI. Recilisib-activated PI3K/Akt singling pathway could restrain apoptosis from inducing miR-23a-5p overexpression, and Miltefosine-blocked PI3K/Akt singling pathway could restrict apoptosis from inhibiting miR-23a-5p reduction. In conclusion, these findings revealed the pivotal role of miR-23a-5p-PI3K/Akt axis in regulating apoptosis during MI, introducing this novel axis as a potential indicator to detect ischemic heart disease and it could be used for therapeutic intervention.
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http://dx.doi.org/10.1002/cbf.3536DOI Listing
December 2020

On the Luminescence Properties and Surface Passivation Mechanism of III- and N-Polar Nanopillar Ultraviolet Multiple-Quantum-Well Light Emitting Diodes.

Micromachines (Basel) 2020 Jun 5;11(6). Epub 2020 Jun 5.

Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.

The non-centrosymmetricity of III-nitride wurtzite crystals enables metal or nitrogen polarity with dramatically different surface energies and optical properties. In this work, III-polar and N-polar nanostructured ultraviolet multiple quantum wells (UV-MQWs) were fabricated by nanosphere lithography and reactive ion etching. The influence of KOH etching and rapid thermal annealing treatments on the luminescence behaviors were carefully investigated, showing a maximum enhancement factor of 2.4 in emission intensity for III-polar nanopillars, but no significant improvement for N-polar nanopillars. The discrepancy in optical behaviors between III- and N-polar nanopillar MQWs stems from carrier localization in III-polar surface, as indium compositional inhomogeneity is discovered by cathodoluminescence mapping, and a defect-insensitive emission property is observed. Therefore, non-radiative recombination centers such as threading dislocations or point defects are unlikely to influence the optical property even after post-fabrication surface treatment. This work lays solid foundation for future study on the effects of surface treatment on III- and N-polar nanostructured light-emitting-diodes and provides a promising route for the design of nanostructure photonic devices.
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http://dx.doi.org/10.3390/mi11060572DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7345201PMC
June 2020

Neural stem cell transplantation improves learning and memory by protecting cholinergic neurons and restoring synaptic impairment in an amyloid precursor protein/presenilin 1 transgenic mouse model of Alzheimer's disease.

Mol Med Rep 2020 Mar 8;21(3):1172-1180. Epub 2020 Jan 8.

Department of Rehabilitation Medicine, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510260, P.R. China.

Alzheimer's disease (AD) is the most prevalent age‑related neurodegenerative disorder. It is featured by the progressive accumulation of β‑amyloid (Aβ) plaques and neurofibrillary tangles. This can eventually lead to a decrease of cholinergic neurons in the basal forebrain. Stem cell transplantation is an effective treatment for neurodegenerative diseases. Previous studies have revealed that different types of stem or progenitor cells can mitigate cognition impairment in different Alzheimer's disease mouse models. However, understanding the underlying mechanisms of neural stem cell (NSC) therapies for AD requires further investigation. In the present study, the effects and the underlying mechanisms of the treatment of AD by NSCs are reported. The latter were labelled with the enhanced green fluorescent protein (EGFP) prior to implantation into the bilateral hippocampus of an amyloid precursor protein (APP)/presenilin 1 (PS1) transgenic (Tg) mouse model of AD. It was observed that the number of basal forebrain cholinergic neurons was restored and the expression of choline acetyltransferase (ChAT) protein was increased. Moreover, the levels of synaptophysin (SYP), postsynaptic density protein 95 (PSD‑95) and microtubule‑associated protein (MAP‑2) were significantly increased in the hippocampus of NSC‑treated AD mice. Notably, spatial learning and memory were both improved after transplantation of NSCs. In conclusion, the present study revealed that NSC transplantation improved learning and memory functions in an AD mouse model. This treatment allowed repairing of basal forebrain cholinergic neurons and increased the expression of the cognition‑related proteins SYP, PSD‑95 and MAP‑2 in the hippocampus.
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http://dx.doi.org/10.3892/mmr.2020.10918DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002968PMC
March 2020

[Effect of rivaroxaban on the injury during endotoxin-induced damage to human umbilical vein endothelial cells].

Zhonghua Wei Zhong Bing Ji Jiu Yi Xue 2019 Apr;31(4):468-473

Department of Cardiothoracic Surgery, Huashan Hospital, Fudan University, Shanghai 200040, China. Corresponding author: Pang Liewen, Email:

Objective: To evaluate the effect and mechanism of rivaroxaban, an inhibitor of coagulation factor Xa (FXa), on endotoxin-induced injury to human umbilical vein endothelial cells (HUVEC).

Methods: When cultured HUVEC grow to 80% fusion, they were divided into four groups according to the random number method: blank control group (DMEM medium), lipopolysaccharide (LPS) group (cells were challenged by 100 μg/L LPS for 16 hours), FXa+LPS group (cells were challenged by LPS for 16 hours after they were cultured with 100 nmol/L FXa for 24 hours), and FXa +RIV+LPS group (cells were challenged by LPS for 16 hours after they were cultured with 100 nmol/L FXa and 1 μmol/L rivaroxaban for 24 hours). After each group of cells were challenged with LPS, the cell activity was detected by the cell proliferation and toxicity kit (CCK-8); the cell migration ability was detected by cell scratch experiments; the abilities of cells migration were measured by scratch-wound-healing assay; the apoptosis of cells were evaluated using flow cytometry; the endothelial barrier of cells was assessed by Transwell and Evans blue; the levels of tumor necrosis factor-α (TNF-α), interleukin (IL-1β, IL-6) were detected by the enzyme linked immunosorbent assay (ELISA); the expressions of nuclear factor-ΚB (NF-ΚB) and mitogen activated protein kinase (MAPK) signaling pathway were detected by Western Blot.

Results: Compared with blank control group, the cell viability in LPS group was significantly decreased, and the migration ability, number of apoptotic cells, and barrier permeability of endothelial cells was significantly increased, the levels of TNF-α, IL-1β and IL-6 were significantly increased, and the expressions of phosphorylation of c-Jun N-terminal kinase (p-JNK), phosphorylation of p38MAPK (p-p38MAPK), phosphorylation of transforming growth factor kinase 1 (p-TAK1) and phosphorylation of NF-ΚBp65 (p-NF-ΚBp65) were significantly increased. It indicated that LPS could stimulate the inflammatory response of vascular endothelial cells, and had a significant impact on cell activity, apoptosis and function. There was no significant difference in above indexes between FXa+LPS group and LPS group, except for the level of IL-6 being higher in FXa+LPS group. Compared with FXa+LPS group, in FXa+RIV+LPS group, the cell activity was significantly increased (A value: 0.42±0.02 vs. 0.33±0.02), and migration ability was significantly decreased (folds: 1.78±0.17 vs. 2.24±0.20), the number of apoptotic cells was significantly decreased [(11.30±0.70)% vs. (21.03±0.19)%], and permeability of monolayers endothelial cells was significantly decreased [(149±12)% vs. (253±15)%], the levels of inflammatory cytokines were significantly decreased [IL-1β (ng/L): 163.2±20.7 vs. 477.8±20.2, IL-6 (ng/L): 69.3±0.5 vs. 238.0±24.1, TNF-α (ng/L): 117.0±13.1 vs. 196.2±4.5], the expressions of p-TAK1 and p-NF-ΚBp65 were significantly decreased (p-TAK1/TAK1: 0.74±0.09 vs. 1.85±0.15, p-NF-ΚBp65/NF-ΚBp65: 1.15±0.17 vs. 2.36±0.20), with statistically significant differences (all P < 0.05). There was no significant difference in the p-JNK, p-p38MAPK expressions between FXa+RIV+LPS group and FXa+LPS group (p-JNK/JNK: 1.64±0.12 vs. 1.65±0.15, p-p38MAPK/p38MAPK: 2.31±0.32 vs. 2.35±0.20, both P > 0.05).

Conclusions: Rivaroxaban can effectively relieve the inflammatory response of HUVEC stimulated by LPS, which may be related to the inhibition of NF-ΚB signaling pathway activation rather than MAPK signaling pathway.
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http://dx.doi.org/10.3760/cma.j.issn.2095-4352.2019.04.019DOI Listing
April 2019

High Density Static Charges Governed Surface Activation for Long-Range Motion and Subsequent Growth of Au Nanocrystals.

Nanomaterials (Basel) 2019 Mar 1;9(3). Epub 2019 Mar 1.

Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo 315201, China.

How a heavily charged metal nanocrystal, and further a dual-nanocrystals system behavior with continuous electron charging? This refers to the electric dynamics in charged particles as well as the crystal growth for real metal particles, but it is still opening in experimental observations and interpretations. To this end, we performed an in-situ electron-beam irradiation study using transmission electron microscopy (TEM) on the Au nanocrystals that freely stand on the nitride boron nanotube (BNNT). Au nanocrystalline particles with sizes of 2⁻4 nm were prepared by a well-controlled sputtering method to stand on the BNNT surface without chemical bonding interactions. Au nanoparticles presented the surface atomic disorder, diffusion phenomena with continuous electron-beam irradiation, and further, the long-range motion that contains mainly the three stages: charging, activation, and adjacence, which are followed by final crystal growth. Firstly, the growth process undergoes the lattice diffusion and subsequently the surface-dominated diffusion mechanism. These abnormal phenomena and observations, which are fundamentally distinct from classic cases and previous reports, are mainly due to the overcharging of Au nanoparticle that produces a surface activation state in terms of high-energy plasma. This work therefore brings about new observations for both a single and dual-nanocrystals system, as well as new insights in understanding the resulting dynamics behaviors.
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http://dx.doi.org/10.3390/nano9030328DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6473974PMC
March 2019

1,520 reference genomes from cultivated human gut bacteria enable functional microbiome analyses.

Nat Biotechnol 2019 02 4;37(2):179-185. Epub 2019 Feb 4.

BGI-Shenzhen, Shenzhen, China.

Reference genomes are essential for metagenomic analyses and functional characterization of the human gut microbiota. We present the Culturable Genome Reference (CGR), a collection of 1,520 nonredundant, high-quality draft genomes generated from >6,000 bacteria cultivated from fecal samples of healthy humans. Of the 1,520 genomes, which were chosen to cover all major bacterial phyla and genera in the human gut, 264 are not represented in existing reference genome catalogs. We show that this increase in the number of reference bacterial genomes improves the rate of mapping metagenomic sequencing reads from 50% to >70%, enabling higher-resolution descriptions of the human gut microbiome. We use the CGR genomes to annotate functions of 338 bacterial species, showing the utility of this resource for functional studies. We also carry out a pan-genome analysis of 38 important human gut species, which reveals the diversity and specificity of functional enrichment between their core and dispensable genomes.
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http://dx.doi.org/10.1038/s41587-018-0008-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6784896PMC
February 2019

Glycyrrhizin has a high likelihood to be a victim of drug-drug interactions mediated by hepatic organic anion-transporting polypeptide 1B1/1B3.

Br J Pharmacol 2018 09 23;175(17):3486-3503. Epub 2018 Jul 23.

State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.

Background And Purpose: Intravenous glycyrrhizin, having anti-inflammatory and hepatoprotective properties, is incorporated into the management of liver diseases in China. This investigation was designed to elucidate the molecular mechanism underlying hepatobiliary excretion of glycyrrhizin and to investigate its potential for drug-drug interactions on organic anion-transporting polypeptide (OATP)1B.

Experimental Approach: Human transporters mediating hepatobiliary excretion of glycyrrhizin were characterized at the cellular and vesicular levels and compared with rat hepatic transporters. The role of Oatp1b2 in glycyrrhizin's elimination and pharmacokinetics was evaluated in rats using the inhibitor rifampin. A physiologically based pharmacokinetic (PBPK) model for glycyrrhizin, incorporating transporter-mediated hepatobiliary excretion, was established and applied to predict potential drug-drug interactions related to glycyrrhizin in humans.

Key Results: Hepatobiliary excretion of glycyrrhizin involved human OATP1B1/1B3 (Oatp1b2 in rats)-mediated hepatic uptake from blood and human multidrug resistance-associated protein (MRP)2/breast cancer resistance protein (ABCP)/bile salt export pump (BSEP)/multidrug resistance protein 1 (Mrp2/Abcp/Bsep in rats)-mediated hepatic efflux into bile. In rats, rifampin impaired hepatic uptake of glycyrrhizin significantly increasing its systemic exposure. Glomerular-filtration-based renal excretion of glycyrrhizin was slow due to extensive protein binding in plasma. Quantitative analysis using the PBPK model demonstrated that OATP1B1/1B3 have critical roles in the pharmacokinetics of glycyrrhizin, which is highly likely to be a victim of drug-drug interactions when co-administered with potent dual inhibitors of these transporters.

Conclusions And Implications: Transporter-mediated hepatobiliary excretion governs glycyrrhizin's elimination and pharmacokinetics. Understanding glycyrrhizin's potential drug-drug interactions on OATP1B1/1B3 should enhance the therapeutic outcome of glycyrrhizin-containing drug combinations on liver diseases.
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http://dx.doi.org/10.1111/bph.14393DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6086986PMC
September 2018

Improving ethanol production and tolerance via RNA polymerase II subunit Rpb7.

Biotechnol Biofuels 2017 15;10:125. Epub 2017 May 15.

School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459 Singapore.

Background: Classical strain engineering methods often have limitations in altering multigenetic cellular phenotypes. Here we try to improve ethanol tolerance and productivity by reprogramming its transcription profile through rewiring its key transcription component RNA polymerase II (RNAP II), which plays a central role in synthesizing mRNAs. This is the first report on using directed evolution method to engineer RNAP II to alter strain phenotypes.

Results: Error-prone PCR was employed to engineer the subunit Rpb7 of RNAP II to improve yeast ethanol tolerance and production. Based on previous studies and the presumption that improved ethanol resistance would lead to enhanced ethanol production, we first isolated variant M1 with much improved resistance towards 8 and 10% ethanol. The ethanol titers of M1 was ~122 g/L (96.58% of the theoretical yield) under laboratory very high gravity (VHG) fermentation, 40% increase as compared to the control. DNA microarray assay showed that 369 genes had differential expression in M1 after 12 h VHG fermentation, which are involved in glycolysis, alcoholic fermentation, oxidative stress response, etc.

Conclusions: This is the first study to demonstrate the possibility of engineering eukaryotic RNAP to alter global transcription profile and improve strain phenotypes. Targeting subunit Rpb7 of RNAP II was able to bring differential expression in hundreds of genes in , which finally led to improvement in yeast ethanol tolerance and production.
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http://dx.doi.org/10.1186/s13068-017-0806-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5433082PMC
May 2017

Improving acetyl-CoA biosynthesis in via the overexpression of pantothenate kinase and PDH bypass.

Biotechnol Biofuels 2017 17;10:41. Epub 2017 Feb 17.

School of Chemical & Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459 Singapore.

Background: Acetyl-CoA is an important precursor in . Various approaches have been adopted to improve its cytosolic level previously with the emphasis on engineering the "acetyl-" part of acetyl-CoA. To the best of our knowledge, there have been no reports on engineering the "-CoA" part so far.

Results: In this study, we had tried to engineer from both the "-CoA" part via pantothenate kinase overexpression (PanK from , the rate-limiting enzyme for CoA synthesis) and the "acetyl-"part through PDH bypass introduction ( from and Se from ). A naringenin-producing reporter strain had been constructed to reflect cytosolic acetyl-CoA level as acetyl-CoA is the precursor of naringenin. It was found that PanK overexpression or PDH bypass introduction alone only led to a twofold or 6.74-fold increase in naringenin titer, but the combination of both (strain CENFPAA01) had resulted in 24.4-fold increase as compared to the control (strain CENF09) in the presence of 0.5 mM substrate -coumaric acid. The supplement of PanK substrate pantothenate resulted in another 19% increase in naringenin production.

Conclusions: To greatly enhance acetyl-CoA level in yeast cytosol, it is feasible to engineer both the "acetyl-" part and the "-CoA" part simultaneously. Insufficient CoA supply might aggravate acetyl-CoA shortage and cause low yield of target product.
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http://dx.doi.org/10.1186/s13068-017-0726-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5316175PMC
February 2017

Insulin resistance plays a potential role in postoperative cognitive dysfunction in patients following cardiac valve surgery.

Brain Res 2017 02 31;1657:377-382. Epub 2016 Dec 31.

Department of Pharmacology, Rush Medical College, Rush University, Chicago, IL 60612, USA.

Severe insulin resistance (IR) promotes the development of Alzheimer disease. IR and postoperative cognitive dysfunction (POCD) are a common complication during the cardiac perioperative period. The authors hypothesized that IR of individuals with cardiac valve surgery would have increased the risk of POCD. The purpose of the study was to analyze the association of IR and POCD after cardiac valve surgery. Total 131 patients who underwent valve replacement via cardiopulmonary bypass (CPB) were included. Cognitive function was assessed by a series of neuropsychological measurements at 1day before and 7days after the surgery. 40 healthy volunteers as the control group also completed the neuropsychological assessment at the same time point. POCD was identified using the "Z score" method. Fasting blood glucose and insulin levels were detected before anesthesia and at 6h and 7days post-operation. Additionally serum levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) were measured at 6h post-operation. The insulin resistance index was calculated by "homeostasis model assessment 2" (HOMA2) software. The relationship between IR and POCD or TNF-α, IL-6 was then analyzed. At 7days after surgery, the incidence of POCD was 43.8%. The levels of HOMA2-IR in patients with POCD were significantly higher than those of patients without POCD at 6h and 7days after operation (P<0.05).The levels of serum IL-6 and TNF- α were positively correlated with HOMA2-IR value at 6h after operation (RIL-6=0.426, P<0.01; RTNF-a=0.381, P<0.01). POCD was correlated with the patients' education age (OR=1.062), CPB time (OR=1.018), self-rating depression scale (SDS) score after operation (OR=1.082), HOMA2-IR at 6h (OR=1.110) and 7days (OR=13.762) after operation, IL-6 (OR=1.036) and TNF-α (OR=1.039) at 6h after operation. Our study suggests that IR is correlated with the incidence of POCD and the increase of inflammatory factors.
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http://dx.doi.org/10.1016/j.brainres.2016.12.027DOI Listing
February 2017

Synergism of Water Shock and a Biocompatible Block Copolymer Potentiates the Antibacterial Activity of Graphene Oxide.

Small 2016 Feb 28;12(7):951-62. Epub 2015 Dec 28.

School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore.

Graphene oxide (GO) is promising in the fight against pathogenic bacteria. However, the antibacterial activity of pristine GO is relatively low and concern over human cytotoxicity further limits its potential. This study demonstrates a general approach to address both issues. The developed approach synergistically combines the water shock treatment (i.e., a sudden decrease in environmental salinity) and the use of a biocompatible block copolymer (Pluronic F-127) as a synergist co-agent. Hypoosmotic stress induced by water shock makes gram-negative pathogens more susceptible to GO. Pluronic forms highly stable nanoassemblies with GO (Pluronic-GO) that can populate around bacterial envelopes favoring the interactions between GO and bacteria. The antibacterial activity of GO at a low concentration (50 μg mL(-1) ) increases from <30% to virtually complete killing (>99%) when complemented with water shock and Pluronic (5 mg mL(-1) ) at ≈2-2.5 h of exposure. Results suggest that the enhanced dispersion of GO and the osmotic pressure generated on bacterial envelopes by polymers together potentiate GO. Pluronic also significantly suppresses the toxicity of GO toward human fibroblast cells. Fundamentally, the results highlight the crucial role of physicochemical milieu in the antibacterial activity of GO. The demonstrated strategy has potentials for daily-life bacterial disinfection applications, as hypotonic Pluronic-GO mixture is both safe and effective.
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http://dx.doi.org/10.1002/smll.201502496DOI Listing
February 2016

Cannabidiol induces expression of human cytochrome P450 1A1 that is possibly mediated through aryl hydrocarbon receptor signaling in HepG2 cells.

Life Sci 2015 Sep 15;136:87-93. Epub 2015 Jul 15.

Department of Hygienic Chemistry, Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3, Kanagawa-machi, Kanazawa 920-1181, Japan; Organization for Frontier Research in Preventive Pharmaceutical Sciences, Hokuriku University, Ho-3, Kanagawa-machi, Kanazawa 920-1181, Japan. Electronic address:

Aims: We herein investigated the inducibility of cytochrome P450 1A1 (CYP1A1) by Δ(9)-tetrahydrocannabinol, cannabidiol (CBD), and cannabinol, three major phytocannabinoids, using human hepatoma HepG2 cells.

Main Methods: The expression of CYP1A1 and the aryl hydrocarbon receptor (AhR) was measured by a quantitative real-time polymerase chain reaction and/or Western blotting.

Key Findings: Δ(9)-Tetrahydrocannabinol and CBD concentration-dependently induced the expression of CYP1A1 mRNA, whereas cannabinol showed little or no induction. Among the phytocannabinoids tested, CBD was the most potent inducer of CYP1A1 expression. The induction of CYP1A1 expression by CBD was significantly attenuated by the knockdown of AhR expression with AhR small interfering RNAs. The role of protein tyrosine kinases (PTKs) in the CBD-mediated induction of CYP1A1 was then examined using herbimycin A, a PTK inhibitor. The upregulation of CYP1A1 by CBD was significantly suppressed by herbimycin A as was the induction by omeprazole but not 3-methylcholanthrene. The inducibility of CYP1A1 by CBD-related compounds was examined to clarify the structural requirements for CBD-mediated CYP1A1 induction. Olivetol, which corresponds to the pentylresorcinol moiety of CBD, significantly induced the expression of CYP1A1, whereas d-limonene, CBD-2'-monomethyl ether, and CBD-2',6'-dimethyl ether did not.

Significance: These results showed that CBD may have induced human CYP1A1 expression through the activation of PTK-dependent AhR signaling, in which two phenolic hydroxyl groups in the pentylresorcinol moiety of CBD may play structurally important roles.
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http://dx.doi.org/10.1016/j.lfs.2015.07.007DOI Listing
September 2015

Transforming Pristine Carbon Fiber Tows into High Performance Solid-State Fiber Supercapacitors.

Adv Mater 2015 Sep 14;27(33):4895-901. Epub 2015 Jul 14.

School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore.

A facile activation strategy can transform pristine carbon fiber tows into high-performance fiber electrodes with a specific capacitance of 14.2 F cm(-3) . The knottable fiber supercapacitor shows an energy density of 0.35 mW h cm(-3) , an ultrahigh power density of 3000 mW cm(-3) , and a remarkable capacitance retention of 68%, when the scan rate increases from 10 to 1000 mV s(-1) .
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http://dx.doi.org/10.1002/adma.201501948DOI Listing
September 2015

cAMP receptor protein (CRP)-mediated resistance/tolerance in bacteria: mechanism and utilization in biotechnology.

Appl Microbiol Biotechnol 2015 Jun 26;99(11):4533-43. Epub 2015 Apr 26.

School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore.

Cyclic AMP receptor protein (CRP) is one of the seven global regulators in Escherichia coli, which regulates the expression of over 490 genes. It contains a cAMP binding N-terminal domain and a DNA binding C-terminal domain, connected via a short hinge region. Various stress-tolerant E. coli mutants had been obtained through transcriptional engineering of CRP. This review aims to shed some light on the possible mechanism behind these CRP variants, from the change in CRP structure, transcription profile, and DNA binding affinity. The amino acid substitutions are distributed along the protein-certain mutations have shown higher frequency than others, such as T127N and D138Y. β-Galactosidase reporter gene assay revealed that CRP mutants had lower binding affinity with all three classes of CRP-dependent promoters as compared to native CRP, which probably would change cellular transcription profile. Different CRP mutants would induce different cellular transcription profile in E. coli, but there are common genes differentially expressed in these variants, including upregulated gadAB and downregulated nontransporter genes aspA and tnaA, and transporter/poringenes malE, mglB, cstA, and lamB. We believe that transcriptional engineering of CRP can provide an alternative strain engineering method for E. coli and its detailed mechanism may need further investigations.
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http://dx.doi.org/10.1007/s00253-015-6587-0DOI Listing
June 2015

Renal tubular secretion of tanshinol: molecular mechanisms, impact on its systemic exposure, and propensity for dose-related nephrotoxicity and for renal herb-drug interactions.

Drug Metab Dispos 2015 May 20;43(5):669-78. Epub 2015 Feb 20.

Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai (W.J., F.D., X.L., R.J., F.X., J.Y., L.L., F.W., O.E.O., J.D., C.L.); Graduate School, Tianjin University of Traditional Chinese Medicine, Tianjin (W.J.); Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing (C.L.), People's Republic of China

Tanshinol has desirable antianginal and pharmacokinetic properties and is a key compound of Salvia miltiorrhiza roots (Danshen). It is extensively cleared by renal excretion. This study was designed to elucidate the mechanism underlying renal tubular secretion of tanshinol and to compare different ways to manipulate systemic exposure to the compound. Cellular uptake of tanshinol was mediated by human organic anion transporter 1 (OAT1) (Km, 121 μM), OAT2 (859 μM), OAT3 (1888 μM), and OAT4 (1880 μM) and rat Oat1 (117 µM), Oat2 (1207 μM), and Oat3 (1498 μM). Other renal transporters (human organic anion-transporting polypeptide 4C1 [OATP4C1], organic cation transporter 2 [OCT2], carnitine/organic cation transporter 1 [OCTN1], multidrug and toxin extrusion protein 1 [MATE1], MATE2-K, multidrug resistance-associated protein 2 [MRP2], MRP4, and breast cancer resistance protein [BCRP], and rat Oct1, Oct2, Octn1, Octn2, Mate1, Mrp2, Mrp4, and Bcrp) showed either ambiguous ability to transport tanshinol or no transport activity. Rats may be a useful model, to investigate the contribution of the renal transporters on the systemic and renal exposure to tanshinol. Probenecid-induced impairment of tubular secretion resulted in a 3- to 5-fold increase in the rat plasma area under the plasma concentration-time curve from 0 to infinity (AUC0-∞) of tanshinol. Tanshinol exhibited linear plasma pharmacokinetic properties over a large intravenous dose range (2-200 mg/kg) in rats. The dosage adjustment could result in increases in the plasma AUC0-∞ of tanshinol of about 100-fold. Tanshinol exhibited very little dose-related nephrotoxicity. In summary, renal tubular secretion of tanshinol consists of uptake from blood, primarily by OAT1/Oat1, and the subsequent luminal efflux into urine mainly by passive diffusion. Dosage adjustment appears to be an efficient and safe way to manipulate systemic exposure to tanshinol. Tanshinol shows low propensity to cause renal transporter-mediated herb-drug interactions.
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http://dx.doi.org/10.1124/dmd.114.062000DOI Listing
May 2015

Combinatorial and high-throughput screening approaches for strain engineering.

Appl Microbiol Biotechnol 2015 Mar 30;99(5):2093-104. Epub 2015 Jan 30.

School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore.

Microbes have long been used in the industry to produce valuable biochemicals. Combinatorial engineering approaches, new strain engineering tools derived from inverse metabolic engineering, have started to attract attention in recent years, including genome shuffling, error-prone DNA polymerase, global transcription machinery engineering (gTME), random knockout/overexpression libraries, ribosome engineering, multiplex automated genome engineering (MAGE), customized optimization of metabolic pathways by combinatorial transcriptional engineering (COMPACTER), and library construction of "tunable intergenic regions" (TIGR). Since combinatorial approaches and high-throughput screening methods are fundamentally interconnected, color/fluorescence-based, growth-based, and biosensor-based high-throughput screening methods have been reviewed. We believe that with the help of metabolic engineering tools and new combinatorial approaches, plus effective high-throughput screening methods, researchers will be able to achieve better results on improving microorganism performance under stress or enhancing biochemical yield.
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http://dx.doi.org/10.1007/s00253-015-6400-0DOI Listing
March 2015

Molecular mechanisms governing different pharmacokinetics of ginsenosides and potential for ginsenoside-perpetrated herb-drug interactions on OATP1B3.

Br J Pharmacol 2015 Feb 20;172(4):1059-73. Epub 2015 Jan 20.

Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China; University of Chinese Academy of Sciences, Shanghai, China.

Background And Purpose: Ginsenosides are bioactive saponins derived from Panax notoginseng roots (Sanqi) and ginseng. Here, the molecular mechanisms governing differential pharmacokinetics of 20(S)-protopanaxatriol-type ginsenoside Rg1 , ginsenoside Re and notoginsenoside R1 and 20(S)-protopanaxadiol-type ginsenosides Rb1, Rc and Rd were elucidated.

Experimental Approach: Interactions of ginsenosides with human and rat hepatobiliary transporters were characterized at the cellular and vesicular levels. A rifampin-based inhibition study in rats evaluated the in vivo role of organic anion-transporting polypeptide (Oatp)1b2. Plasma protein binding was assessed by equilibrium dialysis. Drug-drug interaction indices were calculated to estimate potential for clinically relevant ginsenoside-mediated interactions due to inhibition of human OATP1Bs.

Key Results: All the ginsenosides were bound to human OATP1B3 and rat Oatp1b2 but only the 20(S)-protopanaxatriol-type ginsenosides were transported. Human multidrug resistance-associated protein (MRP)2/breast cancer resistance protein (BCRP)/bile salt export pump (BSEP)/multidrug resistance protein-1 and rat Mrp2/Bcrp/Bsep also mediated the transport of the 20(S)-protopanaxatriol-type ginsenosides. Glomerular-filtration-based renal excretion of the 20(S)-protopanaxatriol-type ginsenosides was greater than that of the 20(S)-protopanaxadiol-type counterparts due to differences in plasma protein binding. Rifampin-impaired hepatobiliary excretion of the 20(S)-protopanaxatriol-type ginsenosides was effectively compensated by the renal excretion in rats. The 20(S)-protopanaxadiol-type ginsenosides were potent inhibitors of OATP1B3.

Conclusion And Implications: Differences in hepatobiliary and in renal excretory clearances caused markedly different systemic exposure and different elimination kinetics between the two types of ginsenosides. Caution should be exercised with the long-circulating 20(S)-protopanaxadiol-type ginsenosides as they could induce hepatobiliary herb-drug interactions, particularly when patients receive long-term therapies with high-dose i.v. Sanqi or ginseng extracts.
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http://dx.doi.org/10.1111/bph.12971DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4314195PMC
February 2015

MicroRNA-191, by promoting the EMT and increasing CSC-like properties, is involved in neoplastic and metastatic properties of transformed human bronchial epithelial cells.

Mol Carcinog 2015 Jun 22;54 Suppl 1:E148-61. Epub 2014 Sep 22.

Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, P.R. China.

Lung cancer is the leading cause of cancer mortality worldwide. A common interest in lung cancer research is the identification of biomarkers for early diagnosis and accurate prognosis. There is increasing evidence that microRNAs (miRNAs) are involved in lung cancer. To explore new biomarkers of chemical exposure in risk assessment of chemical carcinogenesis and lung cancer, we analyzed miRNA expression profiles of human bronchial epithelial (HBE) cells malignantly transformed by arsenite. High-throughput microarray analysis showed that 51 miRNAs were differentially expressed in transformed HBE cells relative to normal HBE cells. In particular, miR-191 was up-regulated in transformed cells. In HBE cells, arsenite induced increases of miR-191 and WT1 levels, decreased BASP1 expression, and activated the Wnt/β-catenin pathway, effects that were blocked by miR-191 knockdown. In addition, a luciferase reporter assay indicated that BASP1 is a direct target of miR-191. By inhibiting the expression of BASP1, miR-191 increased the expression of WT1 to promote activation of Wnt/β-catenin pathway. In transformed cells, inhibition of miR-191 expression blocked the epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC)-like properties of cells and decreased their migratory capacity and neoplastic properties. Thus, these results demonstrate that miR-191 modulates the EMT and the CSC-like properties of transformed cells and indicate that it is an onco-miR involved in the neoplastic and metastatic properties of transformed cells.
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http://dx.doi.org/10.1002/mc.22221DOI Listing
June 2015

Characterization of three Bacillus cereus strains involved in a major outbreak of food poisoning after consumption of fermented black beans (Douchi) in Yunan, China.

Foodborne Pathog Dis 2014 Oct 4;11(10):769-74. Epub 2014 Sep 4.

1 Department of Bioengineering and Pharmaceutical Engineering, Wuhan Polytechnic University , Wuhan, China .

Three Bacillus cereus strains isolated from an outbreak of food poisoning caused by the consumption of fermented black beans (douchi) containing B. cereus is described. The outbreak involved 139 persons who had nausea, vomiting, and diarrhea. The strains were isolated from vomit and the unprepared douchi. Two of the strains produced the emetic toxin cereulide, as evidenced by polymerase chain reaction analysis for the presence of the nonribosomal synthetase cluster responsible for the synthesis of cereulide and by chemical analysis by high-performance liquid chromatography-mass spectrometry. These two strains belong to genetic group III of B. cereus, and multiple locus sequence typing revealed that the type was ST26, as a major part of B. cereus emetic strains. One of these strains produced significantly more cereulide at 37°C than the type cereulide producer (F4810/72), and it was also able to produce the toxin at 40°C and 42°C. The third strain belongs to genetic group IV, and it is a new multiple locus sequence type closely related to strains that are cytotoxic and enterotoxigenic. It possesses genes for hemolysin BL, nonhemolytic enterotoxin, and cytotoxin K2; however, it varies from the majority of strains possessing genes for hemolysin BL by not being hemolytic. Thus, two B. cereus strains producing the emetic toxin cereulide and a strain producing enterotoxins might have been involved in this food-poisoning incident caused by the consumption of a natural fermented food. The ability of one of the strains to produce cereulide at ≥37°C makes it possible that it is produced in the human gut in addition to occurring in the food.
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http://dx.doi.org/10.1089/fpd.2014.1768DOI Listing
October 2014

The acquisition of cancer stem cell-like properties and neoplastic transformation of human keratinocytes induced by arsenite involves epigenetic silencing of let-7c via Ras/NF-κB.

Toxicol Lett 2014 Jun 2;227(2):91-8. Epub 2014 Apr 2.

Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, Jiangsu, PR China; The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, Jiangsu, PR China. Electronic address:

Exposure of humans to inorganic arsenic can cause skin cancer. The acquisition of cancer stem cell-like properties is involved in the initiation of some cancers, and there are changes in let-7 levels in some tumors. The mechanisms of action, however, remain obscure. Here, we report that there are decreased levels of let-7a, let-7b, and let-7c in human keratinocyte HaCaT cells during malignant transformation induced by a low concentration (1.0μM) of arsenite. The process by which arsenite reduces the level of let-7c apparently involves methylation, for 5-aza-2'-deoxycytidine, an inhibitor of methyltransferases, prevents arsenite-induced hypermethylation, decreases the level of let-7c, and thereby blocks arsenite-induced activation of the Ras/NF-κB signal pathway. Let-7c is an up-stream regulator of the Ras/NF-κB signal pathway and down-regulates activation of this pathway. In arsenite-transformed HaCaT cells, the acquisition of cancer stem cell-like properties is prevented by over-expression of let-7c, and over-expression of let-7c decreases the malignancy of transformed HaCaT cells. Thus, we conclude that epigenetic silencing of let-7c via Ras/NF-κB is involved in the acquisition of cancer stem cell-like properties and neoplastic transformation of HaCaT cells induced by arsenite, which contribute to the tumorigenesis of arsenite.
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http://dx.doi.org/10.1016/j.toxlet.2014.03.020DOI Listing
June 2014

Rewiring global regulator cAMP receptor protein (CRP) to improve E. coli tolerance towards low pH.

J Biotechnol 2014 Mar 19;173:68-75. Epub 2014 Jan 19.

School of Chemical & Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore. Electronic address:

Bioprocesses such as production of organic acids or acid hydrolysis of bioresources during biofuel production often suffer limitations due to microbial sensitivity under acidic conditions. Approaches for improving the acid tolerance of these microbes have mainly focused on using metabolic engineering tools. Here, we tried to improve strain acidic tolerance from its transcription level, i.e. we adopted error-prone PCR method to engineer global regulator cAMP receptor protein (CRP) of Escherichia coli to improve its performance at low pH. The best mutant AcM1 was identified from random mutagenesis libraries based on its growth performance. AcM1 almost doubled (0.113h(-1)) the growth rate of the control (0.062h(-1)) at pH 4.24. It also demonstrated better thermotolerance than the control at 48°C, whose growth was completely inhibited at this temperature. Quantitative real time reverse transcription PCR results revealed a stress response overlap among low pH stress-, oxidative stress- and osmotic stress-related genes. The chief enzyme responsible for cell acid tolerance, glutamate decarboxylase, demonstrated over twofold activity in AcM1 compared to the control. Differential binding properties of AcM1 mutant CRP with Class-I, II, and III CRP-dependent promoters suggested that modifications to native CRP may lead to transcription profile changes. Hence, we believe that transcriptional engineering of global regulator CRP can provide a new strain engineering alternative for E. coli.
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http://dx.doi.org/10.1016/j.jbiotec.2014.01.015DOI Listing
March 2014

Enhancing E. coli isobutanol tolerance through engineering its global transcription factor cAMP receptor protein (CRP).

Biotechnol Bioeng 2014 Apr 6;111(4):700-8. Epub 2013 Nov 6.

School of Chemical & Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore.

The limited isobutanol tolerance of Escherichia coli is a major drawback during fermentative isobutanol production. Different from classical strain engineering approaches, this work was initiated to improve E. coli isobutanol tolerance from its transcriptional level by engineering its global transcription factor cAMP receptor protein (CRP). Random mutagenesis libraries were generated by error-prone PCR of crp, and the libraries were subjected to isobutanol stress for selection. Variant IB2 (S179P, H199R) was isolated and exhibited much better growth (0.18 h(-1) ) than the control (0.05 h(-1) ) in 1.2% (v/v) isobutanol (9.6 g/L). Genome-wide DNA microarray analysis revealed that 58 and 308 genes in IB2 had differential expression (>2-fold, p < 0.05) in the absence and presence of 1% (v/v) isobutanol, respectively. When challenged with isobutanol, genes related to acid resistance (gadABCE, hdeABD), nitrate reduction (narUZYWV), flagella and fimbrial activity (lfhA, yehB, ycgR, fimCDF), and sulfate reduction and transportation (cysIJH, cysC, cysN) were the major functional groups that were up-regulated, whereas most of the down-regulated genes were enzyme (tnaA) and transporters (proVWX, manXYZ). As demonstrated by single-gene knockout experiments, gadX, nirB, rhaS, hdeB, and ybaS were found associated with strain isobutanol resistance. The intracellular reactive oxygen species (ROS) level in IB2 was only half of that of the control when facing stress, indicating that IB2 can withstand toxic isobutanol much better than the control.
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http://dx.doi.org/10.1002/bit.25134DOI Listing
April 2014

Improving acetate tolerance of Escherichia coli by rewiring its global regulator cAMP receptor protein (CRP).

PLoS One 2013 4;8(10):e77422. Epub 2013 Oct 4.

School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore.

The presence of acetate exceeding 5 g/L is a major concern during E. coli fermentation due to its inhibitory effect on cell growth, thereby limiting high-density cell culture and recombinant protein production. Hence, engineered E. coli strains with enhanced acetate tolerance would be valuable for these bioprocesses. In this work, the acetate tolerance of E. coli was much improved by rewiring its global regulator cAMP receptor protein (CRP), which is reported to regulate 444 genes. Error-prone PCR method was employed to modify crp and the mutagenesis libraries (~3×10(6)) were subjected to M9 minimal medium supplemented with 5-10 g/L sodium acetate for selection. Mutant A2 (D138Y) was isolated and its growth rate in 15 g/L sodium acetate was found to be 0.083 h(-1), much higher than that of the control (0.016 h(-1)). Real-time PCR analysis via OpenArray(®) system revealed that over 400 CRP-regulated genes were differentially expressed in A2 with or without acetate stress, including those involved in the TCA cycle, phosphotransferase system, etc. Eight genes were chosen for overexpression and the overexpression of uxaB was found to lead to E. coli acetate sensitivity.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0077422PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3790751PMC
May 2014

Arsenite evokes IL-6 secretion, autocrine regulation of STAT3 signaling, and miR-21 expression, processes involved in the EMT and malignant transformation of human bronchial epithelial cells.

Toxicol Appl Pharmacol 2013 Nov 1;273(1):27-34. Epub 2013 Sep 1.

Institute of Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, PR China; The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, PR China.

Arsenite is an established human carcinogen, and arsenite-induced inflammation contributes to malignant transformation of cells, but the molecular mechanisms by which cancers are produced remain to be established. The present results showed that, evoked by arsenite, secretion of interleukin-6 (IL-6), a pro-inflammatory cytokine, led to the activation of STAT3, a transcription activator, and to increased levels of a microRNA, miR-21. Blocking IL-6 with anti-IL-6 antibody and inhibiting STAT3 activation reduced miR-21 expression. For human bronchial epithelial cells, cultured in the presence of anti-IL-6 antibody for 3days, the arsenite-induced EMT and malignant transformation were reversed. Thus, IL-6, acting on STAT3 signaling, which up-regulates miR-21in an autocrine manner, contributes to the EMT induced by arsenite. These data define a link from inflammation to EMT in the arsenite-induced malignant transformation of HBE cells. This link, mediated through miRNAs, establishes a mechanism for arsenite-induced lung carcinogenesis.
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http://dx.doi.org/10.1016/j.taap.2013.08.025DOI Listing
November 2013

MicroRNA-491 is involved in metastasis of hepatocellular carcinoma by inhibitions of matrix metalloproteinase and epithelial to mesenchymal transition.

Liver Int 2013 Sep 3;33(8):1271-80. Epub 2013 Jun 3.

Department of General Surgery, The Second Affiliated Hospital, School of Public Health, Nanjing Medical University, Nanjing, China.

Background & Aims: Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide; the prognosis of HCC patient remains poor owing to intrahepatic and extrahepatic metastasis and postsurgical recurrence. The aim of the present study is to determine the molecular mechanisms underlying the metastasis of HCC.

Methods: HCC patients and treated HCC cells were molecularly characterized by miRNA microarray analysis, qRT-PCR, Western blots, transwell assay, and immunohistochemistry.

Results: Here, by employing a miRNAs microarray analysis, we found that miR-491 level was the most significant down-regulation in poorly differentiated HCC tissue compared with well-differentiated HCC tissue. We then selected HepG2 (very low migratory capacity), MHCC97L (low migratory capacity) and MHCC97H (high migratory capacity), as well as HCC tissues with different status to further investigate the effects of miR-491 on the metastasis of HCC. Our data showed that miR-491 levels were inversely correlated with different status of differentiation in HCC tissues and with migratory potential in HCC cell lines. In HepG2 cells, inhibition of miR-491 increased the expression of matrix metalloproteinase 2/9 (MMP-2/9) and the migratory potential; however, in MHCC97H cells, overexpression of miR-491 level decreased the expression of MMP-2/9 and the migratory capacity. Moreover, miR-491 had a positive relationship with E-cadherin level; however, it had a negative relationship with vimentin level both in cell lines and tissue samples of HCC. MiR-491 levels of non-metastasis HCC tissue are higher than that of metastasis HCC tissue.

Conclusion: Our results suggest that miR-491 is involved in metastasis of HCC by blocking EMT and decreasing MMP-9 levels, which may provide a new clue for preventing tumour metastasis of HCC.
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http://dx.doi.org/10.1111/liv.12190DOI Listing
September 2013

Combinatorial metabolism notably affects human systemic exposure to ginsenosides from orally administered extract of Panax notoginseng roots (Sanqi).

Drug Metab Dispos 2013 Jul 6;41(7):1457-69. Epub 2013 May 6.

Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.

Ginsenosides are medicinal ingredients of the cardiovascular herb Panax notoginseng roots (Sanqi). Here, we implemented a human study (ChiCTR-ONC-09000603; www.chictr.org) to characterize pharmacokinetics and metabolism of ginsenosides from an orally ingested Sanqi-extract (a 1:10 water extract of Sanqi) and the human plasma and urine samples were analyzed by liquid chromatography-mass spectrometry. Plasma and urinary compounds derived from ginsenosides included: 1) intestinally absorbed ginsenosides Ra3, Rb1, Rd, F2, Rg1, and notoginsenoside R1; and 2) the deglycosylated products compound-K, 20(S)-protopanaxadiol, 20(S)-protopanaxatriol, and their oxidized metabolites. The systemic exposure levels of the first group compounds increased as the Sanqi-extract dose increased, but those of the second group compounds were dose-independent. The oxidized metabolites of 20(S)-protopanaxadiol and 20(S)-protopanaxatriol represented the major circulating forms of ginsenosides in the bloodstream, despite their large interindividual differences in exposure level. The metabolites were formed via combinatorial metabolism that consisted of a rate-limiting step of ginsenoside deglycosylation by the colonic microflora and a subsequent step of sapogenin oxidation by the enterohepatic cytochrome P450 enzymes. Significant accumulation of plasma ginsenosides and metabolites occurred in the human subjects receiving 3-week subchronic treatment with the Sanqi-extract. Plasma 20(S)-protopanaxadiol and 20(S)-protopanaxatriol could be used as pharmacokinetic markers to reflect the subjects' microbial activities, as well as the timely-changes and interindividual differences in plasma levels of their respective oxidized metabolites. The information gained from the current study is relevant to pharmacology and therapeutics of Sanqi.
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http://dx.doi.org/10.1124/dmd.113.051391DOI Listing
July 2013

Effect of scraping therapy on interleukin-1 in serum of rats with lumbar disc herniation.

J Tradit Chin Med 2013 Feb;33(1):109-13

Nursing College, Nanjing University of Chinese Medicine, Nanjing 210023, China.

Objective: To explore the effect of scraping therapy on the Interleukin-1 (IL-1) levels of rats with lumbar disc herniation (LDH).

Methods: Fifty male rats were devided into a blank group (A), a sham operation group (B), a model group (C), a scraping group (D), and a drug group (E). The rats in the group B were treated with sham operation, and groups C, D and E were made into the LDH model by operation. After operation, group C were treated with no interventions, D were given scraping and E were fed with azathioprine. Then the IL-1 levels of different groups were detected by enzyme-linked immuno sorbent assay method. And the transplanted coccygeal vertebra discs were observed by pathological section.

Results: The IL-1 levels in the groups C, D, and E were significantly higher than those in the groups A and B (all P < 0.01), which proved the operation was successful. The IL-1 levels in the groups D and E at different periods had statistical significance (F = 414.158, P < 0.01). The treatment periods and interventions have interation (F = 46.613, P < 0.01). Multiple comparison results showed that the IL-1 levels in the groups D and E was significantly lower than that in the group C (P < 0.01), while the IL-1 levels between the groups D and E had no statistical significance (P > 0.05). Moreover, pathological section indicated that immuno-inflammatory response was hardly found in coccygeal vertebra discs in the groups A and B, while local immuno-inflammatory responses of the groups D and E were much lighter than that of the group C.

Conclusion: Scraping therapy could inhibit the immuno-inflammatory responses in the rats with LDH caused by transplantation of autologous nucleus pulposus.
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http://dx.doi.org/10.1016/s0254-6272(13)60110-7DOI Listing
February 2013

Feedback regulations of miR-21 and MAPKs via Pdcd4 and Spry1 are involved in arsenite-induced cell malignant transformation.

PLoS One 2013 1;8(3):e57652. Epub 2013 Mar 1.

Institute of Toxicology, Ministry of Education, School of Public Health, Nanjing, Jiangsu, People's Republic of China.

Objective: To establish the functions of miR-21 and the roles of two feedback regulation loops, miR-21-Spry1-ERK/NF-κB and miR-21-Pdcd4-JNK/c-Jun, in arsenite-transformed human embryo lung fibroblast (HELF) cells.

Methods: For arsenite-transformed HELF cells, apoptosis, clonogenicity, and capacity for migration were determined by Hoechst staining, assessment of their capacity for anchorage-independent growth, and wound-healing, respectively, after blockage, with inhibitors or with siRNAs, of signal pathways for JNK/c-Jun or ERK/NF-κB. Decreases of miR-21 levels were determined with anti-miR-21, and the up-regulation of Pdcd4 and Spry1 was assessed in transfected cells; these cells were molecularly characterized by RT-PCR, qRT-PCR, Western blots, and immunofluorescence assays.

Results: MiR-21 was highly expressed in arsenite-transformed HELF cells and normal HELF cells acutely treated with arsenite, an effect that was concomitant with activation of JNK/c-Jun and ERK/NF-κB and down-regulation of Pdcd4 and Spry1 protein levels. However, there were no significant changes in mRNA levels for Pdcd4 and Spry1, which suggested that miR-21 regulates the expressions of Pdcd4 and Spry1 through translational repression. In arsenite-transformed HELF cells, blockages of JNK/c-Jun or ERK/NF-κB with inhibitors or with siRNAs prevented the increases of miR-21and the decreases of the protein levels but not the mRNA levels of Pdcd4 and Spry1. Down-regulation of miR-21 and up-regulations of Pdcd44 or Spry1 blocked the arsenite-induced activations of JNK/c-Jun or ERK/NF-κB, indicating that knockdown of miR-21 inhibits feedback of ERK activation and JNK activation via increases of Pdcd4 and Spry1 protein levels, respectively. Moreover, in arsenite-transformed HELF cells, inhibition of miR-21 promoted cell apoptosis, inhibited clonogenicity, and reduced migration.

Conclusion: The results indicate that miR-21 is both a target and a regulator of ERK/NF-κB and JNK/c-Jun and the feedback regulations of miR-21 and MAPKs via Pdcd4 and Spry1, respectively, are involved in arsenite-induced malignant transformation of HELF cells.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0057652PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3585869PMC
August 2013