Dysregulation or breakdown of TJs can lead to increased permeability of the BBB, allowing for the influx of harmful substances such as neurotoxic blood-borne products (such as prothrombin, thrombin, fibrinogen, fibrin, pKr-2, albumin), toxic aggregated proteins (such as Aβ and tau), autoantibodies, iron, sodium, cells, and pathogens into the brain, thereby initiating inflammatory and immune responses and contributing to the development of several neurodegenerative diseases [40,41,95]. This evidence concerns the gene F2 and neurodegenerative disease.