While the primary goal of the UPR is to restore ER function and promote cell survival, chronic UPR activation can lead to cell death. This occurs when the adaptive capacity of the UPR is overwhelmed, leading to the activation of apoptotic pathways. Consequently, persistent ER stress and UPR activation are implicated in the pathogenesis of various diseases, including neurodegenerative diseases, diabetes, and cancer, highlighting its significance in toxicology.
