2007;115:1885C4. MI, e.g., -catenin and glycogen synthase kinase-3, was restrained in the LVs of the MI-mice treated by RFP, these inhibition on canonical Wnt signaling was further confirmed in hypoxic NRCMs transfected with FZD1 siRNA. In conclusion, immunization of RFP attenuated cardiac hypertrophy and improved cardiac function in the MI mice via blocking the canonical Wnt signaling pathway. is still far from resolved. Increasing evidences showed that immunotherapy is usually a potential therapeutic approach of cardiac hypertrophy [16]. Thus, we Troxacitabine (SGX-145) hypothesized that targeting the FZD1 may open new pharmacological venues for treating cardiac hypertrophy and heart failure after MI to supplement current drugs that target the sympathetic or renin-angiotensin systems. In the present study, by using an MI mouse model and hypoxia-treated NRCMs, we unravelled a notable attenuation of cardiac hypertrophy after MI led by the immunization of RFP through blocking canonical Wnt signaling pathway. Our findings may provide an optional therapeutic strategy to inhibit pathological cardiac remodelling and improve the cardiac function after MI. RESULTS FZD1 was up-regulated by both MI and hypoxic stimuli To identify the relationship between FZD1 and ischemic cardiac hypertrophy, we measured the expression of FZD1 in cardiomyocytes and study. The mRNA and protein levels of FZD1 were increased by 5.2-folds and 6.0-folds, respectively, in the hypoxia-treated NRCMs compared to the normoxia-treated NRCMs (Physique 1D to 1F). Open in a separate window Physique 1 FZD1 was up-regulated by both MI and hypoxic stimuli(A) mRNA level of FZD1 in the non- infarct mouse left ventricles (LVs) one week after MI. HPRT was served as internal control. (B) Representative Western blots and (C) quantitative results of FZD1 in the LV one week after MI. = 5 per experimental group. * 0.01 compared with sham. (D) mRNA levels of FZD1 in neonatal cardiomyocytes (NRCMs) stimulated by hypoxia. HPRT was served as internal control. (E) Representative Western blots and (F) quantitative results of FZD1 in NRCMs stimulated by hypoxia. = 5 impartial experiments. GAPDH was served as internal control. NO, normoxia. HO, hypoxia. All data are expressed as mean Troxacitabine (SGX-145) S.E.M. * 0.01 compared Troxacitabine (SGX-145) with NO. Deficiency of FZD1 alleviated hypoxia-induced myocardial hypertrophy rather than cell death, indicating a role of FZD1 in the hypoxia-induced myocardial hypertrophy. Open in a separate window Physique 2 Deficiency of FZD1 alleviated hypoxia-induced myocardial hypertrophy = 5 impartial experiments. (B) Quantitative results of the protein expression of FZD1in NRCMs. (C) The representative images of NRCMs stained by – myosin heavy chain (-MHC). (D) The quantification data of NRCM surface area (CSA). (E) mRNA levels of hypertrophic markers, -myosin heavy chain (-MHC) in NRCMs measured by real-time PCR. HPRT was served as internal Rabbit polyclonal to PIWIL2 control. (F) The myocardial apoptosis expressed as the ratio of TUNEL-positive nuclei over DAPI-stained nuclei. = 5 impartial experiments. GAPDH was served as internal control in Western blot. NO, normoxia. HO, hypoxia. All data are expressed as mean S.E.M. * 0.05 compared with NO + Scr SiRNA, # 0.05 compared with HO + Scr SiRNA. Treatment with RFP provoked auto-immunization in mice To provoke auto-immunization response against FZD1, mice were subcutaneously injected with mouse RFP for twice, one at the 1st day and a repeated one at 7th day of the study. The mice were subjected to LAD or sham operation at 21th day after the first injection. Then the mice were sacrificed.