Deposition of Saa Protein and Fibrils in Mouse Brain following Chronic Inflammatory Mice

Prolonged injection of casein results in systemic amyloidosis in mice with impaired hepatic functions due to excessive serum amyloid A (SAA) fibril deposition in liver, spleen, and kidney. We have shown that systemic amyloidosis results in accumulation of SAA fibrils in the brain. The study carried out radiolabeling, Congo red stain, Immuno histochemical studies to source the SAA fibrils that are present in the brain of the affected mice. The experiments suggest that the systemic amyloidosis results in selective crossing of SAA proteins through blood brain barrier (BBB). Injection of 125I SAA to casein treated mice resulted in the accumulation of these proteins in the liver to the maximum extent and to about 20% (compared to liver) localization in the brain. The Congo red stained polarizing microscopic pictures of the cerebral cortex have shown the presence of amyloid fibrils in the brain of the mice with systemic amyloidosis. Immuno histochemical studies also indicate that the abundance of SAA in the mice brain following chronic systemic amyloidosis condition.The present work provides a basis for investigation on the effect of systemic amyloidosis to the brain and it concludes that SAA crosses the blood brain barrier and accumulate in the brain.