VPS13A-knockdown cells show iron-linked vesicles and oxidative vulnerability

Human embryonic kidney 293 cells with reduced expression of VPS13A developed enlarged vesicular structures associated with iron-related oxidative stress in a laboratory study examining endolysosomal changes and ferroptosis-related vulnerability. VPS13A encodes chorein, a protein whose loss causes chorea-acanthocytosis. The researchers had previously found that VPS13A-knockdown cells had impaired efflux of ferrous iron, or Fe(II), increased lipid peroxidation, reduced glutathione peroxidase 4 levels in the cytosolic fraction, and cell death that could be suppressed with ferrostatin-1.

The new study expanded on that earlier work by testing responses to oxidative stress and examining changes involving lysosomal and mitochondrial markers. Exposure to tert-butyl hydroperoxide, an oxidant, produced a significantly greater increase in lipid peroxidation in VPS13A-knockdown cells than in control cells. The added oxidative burden was markedly suppressed by deferasirox, an iron chelator, and by alpha-tocopherol, the form of vitamin E used in the experiments.

These results indicate that the knockdown cells were more susceptible to oxidant-associated lipid damage under the conditions tested. The suppression by deferasirox is consistent with an iron-dependent contribution to the rise in lipid peroxidation, while the response to alpha-tocopherol demonstrates antioxidant protection in this cell model. The experiments do not by themselves establish the complete sequence of events leading to ferroptosis-related cell death.

The study’s most conspicuous new observation was the appearance of enlarged vesicular structures following deferasirox treatment in VPS13A-knockdown cells. Imaging showed spatial overlap of Fe(II), lipid peroxidation and lysosomal signals in these structures. The authors interpreted this pattern as suggesting altered vesicular responses to oxidative stress, but the images did not establish that iron and oxidized lipids accumulated inside the vesicles or demonstrate how the structures formed.

The enlarged vesicles also showed partial spatial overlap with RAB7A, a late-endosomal marker, consistent with involvement of the late endosomal–lysosomal system. Their precise identity and functional significance remained unresolved, and their appearance cannot be treated as proof of a pathological mechanism in human disease. Deferasirox therefore produced two distinct observations in the knockdown cells: it reduced lipid peroxidation while also being associated with prominent vesicular enlargement.

The study did not determine whether the vesicle changes helped protect the cells, contributed to injury, or were a separate consequence of altered iron handling. In contrast, alpha-tocopherol attenuated oxidative injury without producing prominent vesicular accumulation in this model. The comparison distinguishes biochemical protection from morphological alteration: both interventions reduced lipid peroxidation, but they did not produce the same pattern of vesicle changes under the reported conditions.

Because iron chelation also alters cellular iron availability, the experiment does not identify which aspect of iron handling contributed to the enlarged structures. VPS13A-knockdown cells also exhibited mitochondrial morphological abnormalities. A subset of the enlarged vesicles overlapped with TOMM20, a marker of the mitochondrial outer membrane, suggesting changes in the relationship between mitochondria and endolysosomal compartments.

This spatial association does not demonstrate that direct organelle contact caused the vesicle enlargement, mitochondrial abnormalities or ferroptosis-related vulnerability. It therefore characterizes a cellular model and cannot establish clinical effects, treatment efficacy or the full range of disease mechanisms associated with chorea-acanthocytosis. Taken together, the findings connect altered iron handling with endolysosomal vesicular responses, mitochondrial abnormalities and increased lipid peroxidation in VPS13A-knockdown cells, while leaving the causal role and biological meaning of the enlarged vesicles to be determined.

Subject of Research: VPS13A knockdown, iron handling, endolysosomal vesicles and ferroptosis-related vulnerability in HEK293 cells

Article Title: Endolysosomal iron-associated vesicular changes and ferroptosis-related vulnerability in VPS13A-knockdown cells

Article References: Imamura, K., Nishizawa, Y., Sainohira, K., Sakimoto, H., Urata, Y., Sasaki, N., Arai, K., Hiwatashi, H., Yokoyama, I., Sano, A., & Nakamura, M. (2026). Endolysosomal iron-associated vesicular changes and ferroptosis-related vulnerability in VPS13A-knockdown cells. Molecular Biology Reports, 53(1), Article 1471. https://doi.org/10.1007/s11033-026-12649-2

Image Credits: AI Generated

DOI: 10.1007/s11033-026-12649-2

Keywords: VPS13A, chorein, HEK293 cells, iron handling, lipid peroxidation, endolysosomes, ferroptosis, mitochondria, oxidative stress, deferasirox, Endolysosomal, iron-associated