Abstract: Frontotemporal lobar degeneration (FTLD) is a form of progressive dementia characterized by degeneration of the frontal and temporal lobes of the brain. This pathology involves a series of cognitive, behavioral, and neurological symptoms that influence personality, decision-making ability, and language. Although it has been recognized for decades, its exact etiology and underlying mechanisms are still not fully understood. In recent years, however, there has been growing interest in research into factors that may contribute to the development and progression of FTLD. Among these, in a recent study, we observed that serum levels of an inhibitor of plasmin synthesis, the plasminogen activator inhibitor-1 (PAI-1), are elevated in FTLD patients with dementia as compared to healthy controls (Angelucci et al., 2024). Furthermore, we observed a negative correlation between PAI-1 serum levels and disease severity measured by MMSE score.