the doxorubicin-treated WT mice. == Effect of SMP30 deficiency and up-regulation Demethoxycurcumin on DOX-induced cardiac fibrosis == The degree of cardiac fibrosis was significantly higher in the DOX-treated SMP30 KO mice and lower in the DOX-treated SMP30 TG mice compared to the DOX-treated WT mice (P<0.01 and P<0.05, respectively) as shown inFigure 2. ventricular ejection fraction was more severely reduced in the DOX-treated SMP30 KO mice than in the DOX-treated WT mice, but was preserved in the DOX-treated SMP30 TG Demethoxycurcumin mice. Generation of reactive oxygen species and oxidative DNA damage in the myocardium were greater in the DOX-treated SMP30 KO mice than in the DOX-treated WT mice, but much less in the SMP30 TG mice. The numbers of deoxynucleotidyltransferase-mediated dUTP nick end-labeling positive nuclei in the myocardium, apoptotic signaling pathways such as caspase-3 activity, Bax/Bcl-2 ratio and phosphorylation activity of c-Jun N-terminal kinase were increased in SMP30 KO mice and decreased in SMP30 TG mice compared with WT mice after DOX injection. == Conclusions == SMP30 has a cardio-protective role by anti-oxidative and anti-apoptotic effects in DOX-induced cardiotoxicity, and can be a new therapeutic target to prevent DOX-induced heart failure. == Introduction == Anthracyclines are the drugs most closely related to acute and late cardiac toxicity.[1]It has been known since the 1970s that anthracycline treatment is associated with an Demethoxycurcumin increased risk of heart failure, and that this is Rabbit polyclonal to IL13RA1 dependent on cumulative dose and schedule.[2],[3]One of the mechanisms responsible for doxorubicin (DOX) cardiotoxicity is the formation of reactive oxygen species (ROS),[4],[5]which can harm membrane lipids and other cellular components, leading to cardiomyocyte apoptosis and death.[6]In addition, oxidative stress is considered to be an important factor of controlling heart aging.[7] Senescence marker protein 30 (SMP30), a 34-kDa protein, was originally identified as a novel aging marker protein in rat liver, whose expression decreases androgen-independently with age.[8]SMP30 transcripts are detected in almost all organs, and the SMP30 gene is highly conserved among numerous animal species including humans.[9]It has been demonstrated that SMP30 plays multifunctional roles as Ca2+regulator,[10]anti-oxidants,[11]and gluconolactonase which is a key enzyme in the ascorbic acid (vitamin C) biosynthesis.[12]SMP30 knockout (SMP30 KO) mice were generated[13]and showed a shorter life span than that of wild-type (WT) mice on a vitamin C-deficient diet.[14]Using SMP30 KO mice, recent reports have demonstrated that SMP30 functions to protect cells from apoptosis in the liver[13]and that SMP30 has protective effects against age-associated oxidative stress in the brain[15]and lungs[16]. Furthermore, SMP30 KO mice have shown accelerated senescence in the kidney[17]and the worsening of glucose tolerance.[18]Taken together, SMP30 is assumed to behave as an anti-aging factor. Recently, we have demonstrated that deficiency of SMP30 exacerbates angiotensin II-induced cardiac hypertrophy, dysfunction and remodeling in mice.[19] We hypothesized that SMP30 has cardio-protective functions in response to DOX. To test this hypothesis, we generated transgenic mice with cardiac-specific over expression of SMP30 gene (SMP30 TG). Using SMP30 KO mice and SMP30 TG mice, we examined the effects of SMP30 on DOX-induced cardiac dysfunctionin vivo. == Methods == == Ethics statement == The investigations conformed to theGuide for Demethoxycurcumin the Care and Use of Lab Animalspublished by the united states Country wide Institutes of Wellness (NIH publication, 8th Model, 2011). Our analysis protocol was accepted by the Fukushima Medical School Animal Analysis Committee (permit amount 21102), and everything animal experiments had been conducted relative to the guidelines from the Fukushima Medical School Animal Analysis Committee. All initiatives were designed to reduce suffering pets. == Animal process == SMP30 KO (C57BL/6 history) mice had been set up as previously reported.[13]We generated SMP30 TG mice (same C57BL/6 history) with cardiac-specific more than appearance of SMP30 gene using -myosin heavy string promoter as previously reported.[20]Briefly, a 5.5 kb fragment of murine -MHC gene promoter (a sort gift from Dr J. Robbins, Children’s Medical center Research Base, Cincinnati, OH, USA) and 1.6 kb SMP30 cDNA[9]had been subcloned into plasmid. The plasmid was digested with restrictive enzyme to create a DNA fragment made up of the -MHC gene promoter, SMP30 cDNA, and a poly A tail from the hgh. We microinjected the build in to the pronuclei of single-cell fertilized mouse embryos to create TG mice as previously defined.[20]Gene and proteins appearance degrees of SMP30 had been augmented about five-fold and ten-fold in the SMP30 TG mouse hearts.