TUMOR-NECROSIS-FACTOR-ALPHA AUGMENTS AMYLOID-BETA PROTEIN (25-35) INDUCED APOPTOSIS IN HUMAN-CELLS

No information is yet available on the effect of tumor necrosis factor alpha (TNF alpha) on amyloid beta protein (A beta)-induced cytotoxici ty in human cells. For this reason the induction of apoptosis by TNF a lpha and A beta (25-35) was studied in primary cultures of human thyro id and kidney cells as well as in the neuroblastoma line SK-N-SH and i n DU-145 cells. Apoptosis occurred in all cell types after A beta (25- 35) treatment, but was markedly enhanced when TNF alpha was additional ly present. This effect was less pronounced in transformed cell lines than in primary cultures, in which TNF alpha on its own was not cytoto xic. Apoptosis was still more prevalent under serum free culture condi tions. The results demonstrate that TNF alpha may support the occurren ce of A beta-mediated cell death and thus contribute to the developmen t of pathological changes in Alzheimer's disease (AD). (C) 1997 Elsevi er Science Ireland Ltd.