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Pyroptosis is a form of necrotic and inflammatory programmed cell death, which could be characterized by cell swelling, pore formation on plasma membranes, and release of proinflammatory cytokines (IL‐1β and IL‐18). The process of pyroptosis presents as dual effects: protecting multicellular organisms from microbial infection and endogenous dangers; leading to pathological inflammation if overactivated. Two pathways have been found to trigger pyroptosis: caspase‐1 mediated inflammasome pathway with the involvement of NLRP1‐, NLRP3‐, NLRC4‐, AIM2‐, pyrin‐inflammasome (canonical inflammasome pathway) and caspase‐4/5/11‐mediated inflammasome pathway (noncanonical inflammasome pathway). Gasdermin D (GSDMD) has been proved to be a substrate of inflammatory caspases (caspase‐1/4/5/11), and the cleaved N‐terminal domain of GSDMD oligomerizes to form cytotoxic pores on the plasma membrane. Here, we mainly reviewed the up to date mechanisms of pyroptosis, and began with the inflammasomes as the activator of caspase‐1/caspase‐11, 4, and 5. We further discussed these inflammasomes functions in diseases, including infectious diseases, sepsis, inflammatory autoimmune diseases, and neuroinflammatory diseases.

As a selective degradation system, chaperone-mediated autophagy (CMA) is essential for maintaining cellular homeostasis and survival under stress conditions. Increasing evidence points to an important role for the dysfunction of CMA in the pathogenesis of Parkinson disease (PD). However, the mechanisms by which CMA regulates neuronal survival under stress and its role in neurodegenerative diseases are not fully understood. PARK7/DJ-1 is an autosomal recessive familial PD gene. PARK7 plays a critical role in antioxidative response and its dysfunction leads to mitochondrial defects. In the current study, we showed that CMA mediated the lysosome-dependent degradation of PARK7. Importantly, CMA preferentially removed the oxidatively damaged nonfunctional PARK7 protein. Furthermore, CMA protected cells from mitochondrial toxin MPP+-induced changes in mitochondrial morphology and function, and increased cell viability. These protective effects were lost under PARK7-deficiency conditions. Conversely, overexpression of PARK7 significantly attenuated the mitochondrial dysfunction and cell death exacerbated by blocking CMA under oxidative stress. Thus, our findings reveal a mechanism by which CMA protects mitochondrial function by degrading nonfunctional PARK7 and maintaining its homeostasis, and dysregulation of this pathway may contribute to the neuronal stress and death in PD pathogenesis.