- Yoshitaka Morita, M.D., Ph.D., Professor
Main Areas and Themes of Research
Research in our laboratory is directed at elucidating the mechanisms of vascular damage caused by systemic inflammation. Rheumatoid arthritis (RA) is associated with increased cardiovascular mortality, which exceeds that of the general population. Previous studies identified the presence of endothelial dysfunction in RA patients with high inflammatory activity. Consistent with findings in human studies, our laboratory has shown impaired endothelial function in rat adjuvant-induced arthritis (AIA), a well-known animal model of RA. Reactive oxygen species, which likely contribute to the pathophysiology of endothelial dysfunction, were overproduced in the AIA aorta. NAD(P)H oxidases are major sources of reactive oxygen species in the vasculature, and these enzymes were found to be responsible for vascular oxidative stress in AIA. We postulate that further studies using the same model would further our understanding of the pathophysiology of vasculopathies in systemic inflammatory diseases. Indeed, we have recently shown that angiotensin receptor blockers and statins have potent vascular protective effects in the AIA animal model of RA. Further investigations of these approaches using the inflammatory disease model are underway.
Recent publications related to the above research projects:
- Haruna Y, Morita Y, et al. Endothelial dysfunction in rat adjuvant-induced arthritis: vascular superoxide production by NAD(P)H oxidase and uncoupled endothelial nitric oxide synthase. Arthritis Rheum 54: 1847-55, 2006.
- Komai N, Morita Y, et al. Anti-TNF therapy increases serum adiponectin levels with improvement of endothelial dysfunction in patients with rheumatoid arthritis. Mod Rheumatol 17: 385-90, 2007.
- Haruna Y, Morita Y, et al. Fluvastatin reverses endothelial dysfunction and increased vascular oxidative stress in rat adjuvant-induced arthritis. Arthritis Rheum 56: 1827-35, 2007.
- Sakuta T, Morita Y, et al. Involvement of the renin-angiotensin system in the development of vascular damage in a rat arthritis model: effect of angiotensin receptor blockers. Arthritis Rheum 62: 1319-28, 2010.
Our department is dedicated to the diagnosis and treatment of people with rheumatic and musculoskeletal diseases. The conditions we treat include rheumatoid arthritis, systemic lupus erythematosus, vasculitic syndrome, scleroderma, inflammatory myopathies, Sjogren's syndrome, Behcet disease, spondyloarthropathies, polymyalgia rheumatica, gout, osteoarthritis, and osteoporosis.
The educational programs of the department involve teaching activities in the medical school and residency programs in the university hospital. We actively participate in continuing medical educational programs for practicing physicians. The aim of educational program of the department is to contribute towards the training of future physician-scientists in the subspecialty of rheumatology.