OXIDATIVE STRESS IS FOUND IN AMYLOID DEPOSITS IN SYSTEMIC AMYLOIDOSIS

Oxidative stress in human amyloid deposits from patients with systemic amyloidosis, such as familial amyloidotic polyneuropathy (FAP), prima ry amyloidosis, and secondary amyloidosis, was examined immunohistoche mically by means of an affinity purified anti-hydroxynonenal (HNE) ant ibody to HNE, a marker of lipid peroxidation. Furthermore, the levels of thiobarbituric acid reactive substances (TBARS), which is another m arker of lipid peroxidation, and the levels of protein carbonyl, a mak er of protein modifications by free radicals, were determined in FAP p atients and healthy controls. Affinity purified anti-HNE antibody reac ted with amyloid deposits in all types of amyloid tissues examined, Si gnificantly higher levels of TBARS and protein carbonyl were found in amyloid rich tissues of FAP patients compared with those in the contro l subjects. These results verify that lipid peroxidation via free radi cal injury occurs in amyloid deposits in systemic amyloidosis. The pro tein modifying properties of free radicals increase the likelihood tha t they play an important role in the amyloid formation process. (C) 19 97 Academic Press.