Amyloid proteins are misfolded proteins that can accumulate in various tissues and organs, leading to a group of diseases known as amyloidosis. These proteins can disrupt normal cellular functions and cause damage to organs such as the heart, kidneys, and nervous system. In some cases, amyloid proteins are associated with neurodegenerative diseases like Alzheimer's disease, where they form plaques in the brain. The presence of these plaques is linked to cognitive decline and memory loss, highlighting the importance of understanding amyloid proteins in both health and disease.