Pine Pollen Polysaccharides' and Sulfated Polysaccharides' Effects on UC Mice through Modulation of Cell Tight Junctions and RIPK3-Dependent Necroptosis Pathways.

The purpose of this study is to explore the effects of pine pollen polysaccharides and sulfated polysaccharides on mice with ulcerative colitis and whether they could protect mice from inflammation by regulating the tight junctions of colonic epithelial cells and regulating the RIPK3-dependent necroptosis pathways. Pine pollen polysaccharides were prepared by water boiling and ethanol precipitation. After deproteinedization with trichloroacetic acid, the UV spectrum showed that there were no proteins. One polysaccharide component (PPM60-III) was made by gel filtration chromatography, and then sulfated polysaccharide (SPPM60-III) was derived using the chlorosulfonic acid-pyridine method. After treatment with PPM60-III and SPPM60-III, the body weight of mice with ulcerative colitis induced by dextran sodium sulfate increased, the DAI score decreased, the levels of pro-inflammatory factors and inflammation-related enzymes decreased, and the level of anti-inflammatory factors increased. In addition, after treatment, the expressions levels of tight junction proteins increased, the expressions levels of key proteins of programmed necroptosis decreased, while the level of Caspase-8 increased. The results indicated that pine pollen polysaccharides and sulfated polysaccharides have a certain therapeutic effect on UC mice, and the therapeutic effect may be achieved by regulating the tight junction of colonic epithelial cells and regulating the RIPK3-dependent necroptosis pathways.

Astragaloside IV alleviates doxorubicin induced cardiomyopathy by inhibiting NADPH oxidase derived oxidative stress.

Doxorubicin (DOX) is a classic anti-tumor chemotherapeutic used to treat a wide range of tumors. One major downfall of DOX treatment is it can induce fatal cardiotoxicity. Astragaloside IV (AS-IV) is one of the primary active ingredients that can be isolated from the traditional Chinese herbal medicine, Astragalus membranaceus. This study uses both in vitro and in vivo tools to investigate whether AS-IV alleviates DOX induced cardiomyopathy. We found that AS-IV supplementation alleviates body weight loss, myocardial injury, apoptosis of cardiomyocytes, cardiac fibrosis and cardiac dysfunction in DOX-treated mice. Also, DOX-induced cardiomyocyte injury and apoptosis were effectively improved by AS-IV treatment in vitro. NADPH oxidase (NOX) plays an important role in the progress of the oxidative signal transduction and DOX-induced cardiomyopathy. In this study, we found that AS-IV treatment relieves DOX-induced NOX2 and NOX4 expression and oxidative stress in cardiomyocytes. In conclusion, AS-IV, an antioxidant, attenuates DOX-induced cardiomyopathy through the suppression of NOX2 and NOX4.

A potent Cas9-derived gene activator for plant and mammalian cells.

Overexpression of complementary DNA represents the most commonly used gain-of-function approach for interrogating gene functions and for manipulating biological traits. However, this approach is challenging and inefficient for multigene expression due to increased labour for cloning, limited vector capacity, requirement of multiple promoters and terminators, and variable transgene expression levels. Synthetic transcriptional activators provide a promising alternative strategy for gene activation by tethering an autonomous transcription activation domain (TAD) to an intended gene promoter at the endogenous genomic locus through a programmable DNA-binding module. Among the known custom DNA-binding modules, the nuclease-dead Streptococcus pyogenes Cas9 (dCas9) protein, which recognizes a specific DNA target through base pairing between a synthetic guide RNA and DNA, outperforms zinc-finger proteins and transcription activator-like effectors, both of which target through protein-DNA interactions 1 . Recently, three potent dCas9-based transcriptional activation systems, namely VPR, SAM and SunTag, have been developed for animal cells 2-6 . However, an efficient dCas9-based transcriptional activation platform is still lacking for plant cells 7-9 . Here, we developed a new potent dCas9-TAD, named dCas9-TV, through plant cell-based screens. dCas9-TV confers far stronger transcriptional activation of single or multiple target genes than the routinely used dCas9-VP64 activator in both plant and mammalian cells.