Cardioprotective effect of erythropoietin on sepsisinduced myocardial injury in rats

BACKGROUND:Sepsis-induced myocardial injury is one of the major predictors of morbidity and mortality of sepsis.The cytoprotective function of erythropoietin(EPO) has been discovered and extensively studied.However,the cardioprotective effects of EPO on sepsis-induced myocardial injury in the rat sepsis model has not been reported.METHODS:The rat models of sepsis were produced by cecal ligation and perforation(CLP)surgery.Rats were randomly(random number) assigned to one of three groups(n=8 for each group):sham group,CLP group and EPO group(1000 lU/kg erythropoietin).Arterial blood was withdrawn at3,6,12,and 24 hours after CLP.cTnl,BNP,CK-MB,LDH,AST,TNF-a,IL-6,IL-10,and CRP were tested by the ELISA assay.Changes of hemodynamic parameters were recorded at 3,6,12,24 hours after the surgery.Histological diagnosis was made by hematoxylin and eosin.Flow cytometry was performed to examine cell apoptosis,myocardium mitochondrial inner membrane potential,and NF-κB(p65).Survival rate at 7 days after CLP was recorded.RESULTS:In the CLP group,myocardial enzyme index and inflammatory index increased at3,6,12 and 24 hours after CLP compared with the sham group,and EPO significantly blocked the increase.Compared with the CLP group,EPO significantly improved LVSP,LV +dpldt_(max) LV-dp/dt_(min),and decreased LVEDP at different time.EPO blocked the reduction of mitochondrial transmembrane potential,suppressed the cardiomyocyte apoptosis,inhibited the activation of NF-κB,and reduced the production of proinflmmatory cytokines.No difference in the survival rate at 7 days was observed between the CLP group and the EPO group.CONCLUSION:Exogenous EPO has cardioprotective effects on sepsis-induced myocardial injury.

Zinc-finger protein GmZF351 improves both salt and drought stress tolerance in soybean

Abiotic stress is one of the most important factors reducing soybean yield. It is essential to identify regulatory factors contributing to stress responses.A previous study found that the tandem CCCH zincfinger protein Gm ZF351 is an oil level regulator. In this study, we discovered that the Gm ZF351 gene is induced by stress and that the overexpression of Gm ZF351 confers stress tolerance to transgenic soybean. Gm ZF351 directly regulates the expression of Gm CIPK9 and Gm SnRK, leading to stomata closing, by binding to their promoter regions, which carry two CT(G/C)(T/A)AA elements.Stress induction of Gm ZF351 is mediated through reduction in the H3K27me3 level at the Gm ZF351locus.TwoJMJ30-demethylase-likegenes,Gm JMJ30-1 and Gm JMJ30-2, are involved in this demethylationprocess.Overexpressionof Gm JMJ30-1/2 in transgenic hairy roots enhances Gm ZF351 expression mediated by histone demethylation and confers stress tolerance to soybean.Yield-related agronomic traits were evaluated in stable Gm ZF351-transgenic plants under mild drought stress conditions. Our study reveals a new mode of Gm JMJ30-Gm ZF351 action in stress tolerance, in addition to that of Gm ZF351 in oil accumulation. Manipulation of the components in this pathway is expected to improve soybean traits and adaptation under unfavorable environments.

Soybean miR172a Improves Salt Tolerance and Can Function as a Long-Distance Signal

Dear Editor Soybean is an important crop for oil and protein resources but its growth and development may e6counter various abiotic stresses, including high salinity, that can hinder soybean production. Manipulation of soybean stress tolerance requires a thorough understanding of the mechanisms underlying plant response to stresses. Evolutionarily, plants have developed multiple gene regulatory mechanisms to adjust cellular activities for better survival under stress conditions, and one of these is microRNA （miRNA）-medi- ated gene silencing （Zhang, 2015）. Many conserved and novel miRNAs have been identified in different organs of soybean and in different processes during soybean development （Song et al., 2011）. However, these soybean miRNAs were seldom studied in stress response. Previously, we have identified multiple stressresponsive transcription factor genes from soybean and analyzed their functions in stress response （Wei et al., 2009; Wang et al., 2015）. Now we intend to explore the role of miRNAs in the regulation of soybean response to stresses. Among our previously identified miRNAs from soybean （Song et al., 2011）, the gma-miR172a can be induced by salt and other stresses, and so was selected for further investigation.