[Amyloidosis and oxidative stress].

Recent studies on oxidative stress have revealed that free radical injury appears to be involved in either the amyloid formation process or in post-fibrillar modification in several types of amyloidosis. Here, we report the role of oxidative stress in the pathogenesis of dialysis-related amyloidosis(DRA) and familial amyloidotic polyneuropathy(FAP), and propose radical scavenger treatment for such amyloidosis. For patients under maintenance hemodialysis, EC-SOD Arg213Gly was a risk factor for the progression of DRA, atherosclerosis, and renal failure causing hemodialysis. In FAP patients who had EC-SOD Arg213Gly, massive amyloid deposition which may be related to increased oxidative stress in loco was found especially prominently around blood vessels in the interstitial tissues. Histological and biochemical examinations revealed that oxidative stress is deeply connected with amyloid formation mechanisms in FAP. We started radical scavenger therapy, such as N-acetyl cysteine, vitamin E and vitamin C in 20 Swedish FAP patients for 6 months. Although no improvement was found in the amount of amyloid deposition in biopsy specimens, modified body mass index(mBMI), an index of nutritional status, tended to be increased, suggesting the therapeutic possibility of radical scavenger treatment for amyloidosis.