Rikuta Hamaya

Tokyo Medical and Dental University, Tokyo, Tokyo-to, Japan

Are you Rikuta Hamaya?

Claim your profile

Publications (2)5.98 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background: Neointimal hyperplasia after the percutaneous coronary intervention is still a clinically serious problem, associated with the risk of thrombosis due to delayed reendothelization. Peroxisome proliferator-activated receptor-β/δ (PPAR-β/δ) belongs to a family of ligand-activated transcription factors. Objectives: In this study, we investigated the effects of GW-0742, a synthetic high-affinity PPAR-β/δ agonist, on neointimal hyperplasia after arterial injury. Using C57BL/6J mice, we made a wire-injury model and intraperitoneally injected GW-0742 or vehicle once a day. The arteries were harvested for pathological and molecular analysis on day 14 after injury. In vitro, vascular smooth muscle cells (VSMCs), macrophages and human umbilical vein endothelial cells (HUVECs) were cultured, and GW-0742 effects on the cells proliferation were measured. Results: The vehicle-treated injured arteries showed significantly thickened intima, while GW-0742 suppressed it. GW-0742 significantly suppressed IL-6 protein production, the expression of proliferating cell nuclear antigen in the neointima and enhanced CD31 expression. In vitro, GW-0742 attenuated VSMC proliferation triggered by cytokines or macrophages. The drug also induced endothelial regeneration after denudation injury. Conclusion: The data suggest that the PPAR-β/δ agonist is effective for atten- uation of neointimal hyperplasia by suppressing VSMC proliferation and accelerating reendothelization.
    Expert Opinion on Investigational Drugs 08/2013; · 4.74 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Restenosis after percutaneous coronary intervention (PCI) is still a clinically serious problem. We examined the treatment efficacy of IMD-0354, a novel IKK inhibitor, on arteriopathy. Using C57BL/6J mice, a wire-injury model was prepared and the mice were intraperitoneally injected with IMD-0354 or vehicle twice a day. The vehicle-treated injured arteries showed significantly thickened intima (3.77 ± 0.59, n = 8), however, IMD-0354 suppressed its progression (1.62 ± 0.22, n = 10, P < 0.05) on day 28. While enhanced expression of PCNA and NF-κB was observed in the untreated injured arteries, IMD-0354 significantly suppressed their expressions. Quantitative RT-PCR revealed that the expression of several inflammatory factors was reduced in the arteries from mice which received IMD-0354 treatment compared with the control animals. Thus, this drug may effectively prevent restenosis after coronary intervention and other cardiovascular diseases.
    International Heart Journal 01/2012; 53(2):133-8. · 1.23 Impact Factor