MKL1 mediates TNF-α induced pro-inflammatory transcription by bridging the crosstalk between BRG1 and WDR5

Tumor necrosis factor alpha(TNF-a) is a cytokine that can potently stimulate the synthesis of a range of proinflammatory mediators in macrophages. The underlying epigenetic mechanism, however, is underexplored. Here we report that the transcriptional modulator megakaryocytic leukemia 1(MKL1) is associated with a histone H3 K4 methyltransferase activity. Re-ChIP assay suggests that MKL1 interacts with and recruits WDR5, a component of the COMPASS complex responsible for H3 K4 methylation, to the promoter regions of pro-inflammatory genes in macrophages treated with TNF-α. WDR5 enhances the ability of MKL1 to stimulate the promoter activities of proinflammatory genes. In contrast, silencing of WDR5 attenuates TNF-a induced production of pro-inflammatory mediators and erases the H3 K4 methylation from the gene promoters. Of interest, the chromatin remodeling protein BRG1 also plays an essential role in maintaining H3 K4 methylation on MKL1 target promoters by interacting with WDR5. MKL1 knockdown disrupts the interaction between BRG1 and WDR5. Together, our data illustrate a role for MKL1 in moderating the crosstalk between BRG1 and WDR5 to activate TNF-a induced pro-inflammatory transcription in macrophages.

Functional isolation,culture and cryopreservation of adult human primary cardiomyocytes

Cardiovascular diseases are the most common cause of death globally.Accurately modeling cardiac homeostasis,dysfunction,and drug response lies at the heart of cardiac research.Adult human primary cardiomyocytes(hPCMs)are a promising cellular model,but unstable isolation efficiency and quality,rapid cell death in culture,and unknown response to cryopreservation prevent them from becoming a reliable and flexible in vitro cardiac model.Combing the use of a reversible inhibitor of myosinⅡATPase,(-)-blebbistatin(Bleb),and multiple optimization steps of the isolation procedure,we achieved a 2.74-fold increase in cell viability over traditional methods,accompanied by better cellular morphology,minimally perturbed gene expression,intact electrophysiology,and normal neurohormonal signaling.Further optimization of culture conditions established a method that was capable of maintaining optimal cell viability,morphology,and mitochondrial respiration for at least 7 days.Most importantly,we successfully cryopreserved hPCMs,which were structurally,molecularly,and functionally intact after undergoing the freeze-thaw cycle.hPCMs demonstrated greater sensitivity towards a set of cardiotoxic drugs,compared to human-induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs).Further dissection of cardiomyocyte drug response at both the population and single-cell transcriptomic level revealed that hPCM responses were more pronouncedly enriched in cardiac function,whereas hiPSC-CMs responses reflected cardiac development.Together,we established a full set of methodologies for the efficient isolation and prolonged maintenance of functional primary adult human cardiomyocytes in vitro,unlocking their potential as a cellular model for cardiovascular research,drug discovery,and safety pharmacology.

Syntheses, Cytotoxicity and Properties of CO Releasing Molecules Containing Acetyl Salicylamide-3-pyridine

A series of CO-releasing molecules [M（CO）5L] （M=Cr, W, Mo, L=acetyl salicylamide 3-pyridine, 1--3; L= N,N-dimethyl-4-pyridine, 4-6; L=nicotinamide, 7--9; L=4-CHO-pyridine, 10--12） were synthesized. And in this paper, we have investigated mainly cytotoxicity and properties of the CO-releasing molecules containing acetyl salicyamide-3-pyridine, namely complexes 1--3. The stability of complexes 1 and 2 was evaluated by means of UV-Vis spectroscopy and 1H NMR spectra. The results indicate complexes 1 and 2 were stable in methanol and acidic aqueous solution, but unstable and decayed in basic media （pH 10.0）. Among all the complexes, complex 2 was the slowest CO-releaser, and its half-life was 73.8 min. Complex 9 containing nicotinamide was the fastest CO-releaser with half-life only 6.5 min. In addition, cytotoxic effects of all the complexes on the proliferation of fibroblast line were assayed by MTT. Among all the complexes, the IC50 of complex 1 was 6 μmol/L, revealing complex 1 possessed stronger antiproliferative activity than the control. Analysis by Flow cytometry revealed that complex 1 arrested Hela cells in S phase while complexes 2 and 8 arrested in G2/M phase. Cell apoptosis caused by the complexes mainly occurred in ＂Late apoptosis＂.

Study on pharmacokinetics and tissue distribution of the isocorydine derivative (AICD) in rats by HPLC-DAD method

A simple and effective high-performance liquid chromatography with diode-array detection method coupled with a liquid liquid extraction pretreatment has been developed for determining the pharmacokinetics and tissue distribution of a novel structurally modified derivative (8-acetamino-isocorydine) of isocorydine. According to the in vivo experiments data calculations by DAS 2.0 software, a two compartment metabolic model was suitable for describing the pharmacokinetic of 8-acetaminoiso-corydine in rats. 8-Acetamino-isocorydine was absorbed well after oral administration, and the absolute bioavailability was 76.5%. The half-life of 8-acetamino-isocorydine after intravenous and oral administration was 2.2 h and 2.0 h, respectively. In Oro, 8-acetamino-isocorydine was highly distributed in the lungs, kidney and liver; however, relatively little entered the brain, suggesting that 8-acetaminoisocorydine could not easily pass through the blood brain bather. Our work describes the first characterization of the pharmacokinetic parameters and tissue distribution of 8-acetamino-isocorydine. The acquired data will provide useful infonnation for the in vivo pharmacology of 8-acetaminoisocorydine, and can he applied to new drug research. (C) 2015 Chinese Pharmaceutical Association and Institute of Materia IMedica, Chinese Academy of 'Medical Sciences. Production and hosting by Elsevier B.V.