Peroxisomes generate reactive oxygen species (ROS) and also play a role in protecting cells from the damaging effects of such radicals. Dysfunctional peroxisomes are recognized by receptors and degraded by a selective type of macroautophagy called pexophagy. Oxidative stress is one of the signals that activates pexophagy through multiple signaling pathways. Conversely, impaired pexophagy results in the accumulation of damaged peroxisomes, which in turn leads to elevated ROS levels and oxidative stress, resulting as cellular dysfunction and the progression of diseases such as neurodegeneration, cancer, and metabolic disorders. This review explores the molecular mechanisms driving pexophagy and its regulation by oxidative stress with a particular focus on ROS. This highlights the role of peroxisomal proteins and ROS-mediated signaling pathways in regulating pexophagy. In addition, emerging evidence suggests that the dysregulation of pexophagy is closely linked to neurological disorders, underscoring its potential as a therapeutic target. Understanding the intricate crosstalk between pexophagy and oxidative stress provides new insights into the maintenance of cellular homeostasis and offers promising directions for addressing neurological disorders that are tightly associated with pexophagy and oxidative stress.

Background: The kidney is an organ rich in peroxisomes, which play a pivotal role in fatty acid oxidation and ROS decomposition. Importantly, peroxisomal dysfunction contributes to the development and progression of various renal diseases. Therefore, we aimed to elucidate whether peroxisomes affect renal damage and fibrosis over time using a unilateral ureteral obstruction (UUO) mouse model. Methods: Expression levels of peroxisome-related factors and ROS- and hypoxia-related genes in UUO mice were measured in a time-dependent manner. Results: UUO led to renal damage and fibrosis progression over time; it significantly increased the protein expression levels of ATG5 and ATG7, while it decreased PMP70 and PEX14 protein expression. In particular, UUO increased the protein expression level of pexophagy receptor NBR1. Although the number of peroxisomes decreased, the protein expression levels of peroxisomal biogenesis-related proteins such as PEX11b, PEX16, and PEX19 remained constant. Decreased lipid metabolism due to reductions in ACOX1, DBP, and catalase caused by UUO and increased ROS production through peroxisomal degradation and mitochondrial antioxidant enzyme dysfunction were observed. Additionally, HIF-1α protein levels gradually increased in the UUO mice, whereas those of HIF-2α initially increased and then decreased. Conclusions: UUO is characterized by a progressive, chronological reduction in peroxisomal markers. Our findings indicate that peroxisomal degradation and associated metabolic dysfunction are tightly correlated with the progression of kidney injury and fibrosis, suggesting a potential involvement of compromised peroxisomal homeostasis in renal pathogenesis rather than proving a direct causal mechanism. Maintaining peroxisomal quality control may nevertheless represent a potential therapeutic avenue for chronic kidney disease.

Solute carrier family 25 (SLC25) is known to facilitate the transport of diverse metabolites across the mitochondrial and peroxisomal membranes. SLC25A17 is the only member of the SLC25 protein localized to peroxisomes; formerly known as PMP34, it also shares conserved sequence features with other SLC families. SLC25A17 was first described as an ATP transporter, but conflicting results regarding cofactor specificity in various experimental models obscure its precise function. Similarly, phenotypic differences between experimental models, such as mice and zebrafish, complicate the application of animal studies to humans. In particular, SLC25A17 deficiency is associated with peroxisomal dysfunction, and SLC25A17 expression is affected in various cancers and bipolar disorder, while the underlying molecular mechanisms remain unknown. Furthermore, it remains unclear whether altered SLC25A17 expression is a cause or consequence of human disease. This review provides an overview on current knowledge of SLC25A17, focusing on its known functions and emerging roles in human diseases. This may also help future studies in understanding its metabolic significance and disease pathogenesis.