Melatonin reduces interleukin secretion in amyloid-beta stressed mouse brain slices.

Neurodegeneration in Alzheimer's disease (AD) is associated with many features of the immune system. For example, cytokines such as IL-6, synthesized by microglia and astrocytes, are associated with senile plaques. To further study the role of cytokines in early stage AD neurodegeneration, an organotypic mouse brain slice culture system with microglia and astrocytes was developed. Amyloid-beta(Abeta1-40) induced the secretion of both IL-1beta and IL-6. Melatonin, an antioxidant and pineal hormone, reduced interleukin secretion in a concentration dependent manner. We also observed that melatonin, alone, had no effect on IL-1beta secretion but at a concentration of 500 microM induced the secretion of IL-6. This organotypic slice system can be used to study the early role of immune system molecules on neurodegeneration.