Shotgun protein profile of human adipose tissue and its changes in relation to systemic amyloidoses.

In systemic amyloidosis, accumulation of misfolded proteins as extracellular amyloid fibrils in tissues causes severe organ dysfunction, but the molecular events of tissue damage related to amyloid deposition are still largely unknown. Through the use of the MudPIT proteomic approach, comprehensive protein profiles of human amyloid-affected adipose tissue from patients and its control (non-amyloid-affected) counterpart were acquired. Label-free comparison between patients and controls made it possible to highlight differences related to the presence of amyloid, by describing up- and down-represented proteins, connected into interacting networks. In particular, extracellular matrix (ECM), protein folding, lipid metabolism, and mitochondrial functions were among the most affected structural/functional pathways. The reported results, obtained with no a priori hypotheses, represent a significant step forward in the clarification of the molecular mechanisms involved in amyloidoses at tissue level and are the premise for understanding protein misfolding diseases.