Potentilla anserina polysaccharide alleviates cadmium-induced oxidative stress and apoptosis of H9c2 cells by regulating the MG53-mediated RISK pathway

Oxidative stress plays a crucial role in cadmium(Cd)-induced myocardial injury.Mitsugumin 53(MG53)and its mediated reperfusion injury salvage kinase(RISK)pathway have been demonstrated to be closely related to myocardial oxidative damage.Potentilla anserina L.polysaccharide(PAP)is a polysaccharide with antioxidant capacity,which exerts protective effect on Cd-induced damage.However,it remains unknown whether PAP can prevent and treat Cd-induced cardiomyocyte damages.The present study was desgined to explore the effect of PAP on Cd-induced damage in H9c2 cells based on MG53 and the mediated RISK pathway.For in vitro evaluation,cell viability and apoptosis rate were analyzed by CCK-8 assay and flow cytometry,respectively.Furthermore,oxidative stress was assessed by 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA)staining and using superoxide dismutase(SOD),catalase(CAT),and glutathione/oxidized glutathione(GSH/GSSG)kits.The mitochondrial function was measured by JC-10 staining and ATP detection assay.Western blot was performed to detect the expression of proteins related to MG53,the RISK pathway,and apoptosis.The results indicated that Cd increased the levels of reactive oxygen species(ROS)in H9c2 cells.Cd decreased the activities of SOD and CAT and the ratio of GSH/GSSG,resulting in decreases in cell viability and increases in apoptosis.Interestingly,PAP reversed Cd-induced oxidative stress and cell apoptosis.Meanwhile,Cd reduced the expression of MG53 in H9c2 clls and inhibited the RISK pathway,which was mediated by decreasing the ratio of p-Akt^(Ser473)/Akt,p-GSK3β^(Ser9)/GSK3β and p ERK1/2/ERK1/2.In addition,Cd impaired mitochondrial function,which involved a reduction in ATP content and mitochondrial membrane potential(MMP),and an increase in the ratio of Bax/Bcl-2,cytoplasmic cytochrome c/mitochondrial cytochrome c,and Cleaved-Caspase 3/Pro-Caspase 3.Importantly,PAP alleviated Cd-induced MG53 reduction,activated the RISK pathway,and reduced mitochondrial damage.Interestingly,knockdown of MG53 or inhibition of the RISK pathway attenuated the protective effect of PAP in Cd-induced H9c2 cells.In sum,PAP reduces Cd-induced damage in H9c2 cells,which is mediated by increasing MG53 expression and activating the RISK pathway.

Identification of Risk Pathways and Functional Modules for Coronary Artery Disease Based on Genome-wide SNP Data

Coronary artery disease （CAD） is a complex human disease, involving multiple genes and their nonlinear interactions, which often act in a modular fashion. Genome-wide single nucleotide polymorphism （SNP） profiling provides an effective technique to unravel these underlying genetic interplays or their functional involvements for CAD. This study aimed to identify the susceptible pathways and modules for CAD based on SNP omics. First, the Wellcome Trust Case Control Consortium （WTCCC） SNP datasets of CAD and control samples were used to assess the joint effect of multiple genetic variants at the pathway level, using logistic kernel machine regression model. Then, an expanded genetic network was constructed by integrating statistical gene-gene interactions involved in these susceptible pathways with their protein protein interaction （PPI） knowledge. Finally, risk functional modules were identified by decomposition of the network. Of 276 KEGG pathways analyzed, 6 pathways were found to have a significant effect on CAD. Other than glycerolipid metabolism, glycosaminoglycan biosynthesis, and cardiac muscle contraction pathways, three pathways related to other diseases were also revealed, including Alzheimer＇s disease, non-alcoholic fatty liver disease, and Huntington＇s disease. A genetic epistatic network of 95 genes was further constructed using the abovementioned integrative approach. Of 10 functional modules derived from the network, 6 have been annotated to phospholipase C activity and cell adhesion molecule binding, which also have known functional involvement in Alzheimer＇s disease. These findings indicate an overlap of the underlying molecular mechanisms between CAD and Alzheimer＇s disease, thus providing new insights into the molecular basis for CAD and its molecular relationships with other diseases.

Er-xian ameliorates myocardial ischemia-reperfusion injury in rats through RISK pathway involving estrogen receptors

Curculigo orchioides(CUR)and Epimedium(EPI)are traditional Chinese medicines with estrogen-like biological activity,called Xianmao and Xianlingpi(Er-xian)in Chinese.However,whether Er-xian exerts protective effects on myocardial ischemia-reperfusion injury(MIRI)is unknown.This study aimed to investigate the cardioprotective effects of Er-xian preconditioning against MIRI and the underlying mechanisms.CUR or EPI was administered intragastrically to aged female rats as a monotherapy or combination therapy.2 weeks later,a rat MIRI model was established.Myocardial infarction size,myocardial morphology,cTnT,cell apoptosis rate,intracellular calcium concentration,mitochondrial permeability transition pore(MPTP)opening and reperfusion injury salvage kinase(RISK)signaling pathway molecules were observed after the surgery.To evaluate the mechanisms of Er-xian,estrogen receptors antagonists ICI 182780 and G15 were used.In this study,Er-xian notably alleviated myocardial tissue damage,maintained mitochondrial morphology,reduced infarct size and cardiac markers,and increased sera levels of E2.Moreover,Er-xian inhibited calcium overload and mPTP opening,and decreased cardiomyocyte apoptosis.We found that the dual therapy of CUR and EPI elicited more noticeable results than CUR or EPI monotherapy.The significant protective effects of Er-xian on ischemia-reperfusion myocardium were attributed to the up-regulation of AKT,ERK1/2 and GSK-3βphosphorylation levels.The cardioprotective effects of Er-xian were significantly reduced after estrogen receptor blockade,especially GPER30.These results indicate that Er-xian attenuates MIRI through RISK signaling pathway and estrogen receptors are the critical mediators.

Significance of adverse outcome pathways in biomarker-based environmental risk assessment in aquatic organisms

In environmental risk assessments（ERA）, biomarkers have been widely used as an early warning signal of environmental contamination. However, biomarker responses have limitation due to its low relevance to adverse outcomes（e.g., fluctuations in community structure, decreases in population size, and other similar ecobiologically relevant indicators of community structure and function）. To mitigate these limitations, the concept of adverse outcome pathways（AOPs） was developed. An AOP is an analytical, sequentially progressive pathway that links a molecular initiating event（MIE） to an adverse outcome. Recently, AOPs have been recognized as a potential informational tool by which the implications of molecular biomarkers in ERA can be better understood. To demonstrate the utility of AOPs in biomarker-based ERA, here we discuss a series of three different biological repercussions caused by exposure to benzo（a）pyrene（Ba P）, silver nanoparticles（Ag NPs）, and selenium（Se）. Using mainly aquatic invertebrates and selected vertebrates as model species, we focus on the development of the AOP concept. Aquatic organisms are suitable bioindicator species whose entire lifespans can be observed over a short period; moreover, these species can be studied on the molecular and population levels.Also, interspecific differences between aquatic organisms are important to consider in an AOP framework, since these differences are an integral part of the natural environment.The development of an environmental pollutant-mediated AOP may enable a better understanding of the effects of environmental pollutants in different scenarios in the diverse community of an ecosystem.