In vitro exposure to polystyrene microplastic induces oxidative stress mediated β-cell dysfunction

Area of Science:

• Environmental Science
• Toxicology
• Endocrinology

Background:

• Microplastics (MPs) are widespread environmental pollutants found in human tissues.
• Polystyrene microplastics (PS-MPs) are frequently detected in metabolically active organs.
• Concerns exist regarding the role of PS-MPs in diabetes development.

Purpose of the Study:

• To investigate the cellular and functional effects of PS-MP exposure on pancreatic beta cells.
• To determine the impact of PS-MPs on beta cell viability, oxidative stress, and function.

Main Methods:

• Utilized the MIN6 cell line to model pancreatic beta cells.
• Exposed cells to 1 μm PS-MPs.
• Assessed PS-MP internalization, localization, reactive oxygen species (ROS) production, mitochondrial superoxide levels, cell viability, and expression of beta cell markers (PDX1, MAFA).

Main Results:

• PS-MPs were internalized and localized in pancreatic beta cells.
• PS-MP exposure increased oxidative stress (superoxide and ROS) in a dose- and time-dependent manner.
• Significant suppression of beta cell function markers, reduced viability, and increased necrotic cell death were observed.
• PDX1 and MAFA expression was suppressed, indicating impaired beta cell identity.

Conclusions:

• PS-MP exposure induces oxidative stress, cytotoxicity, and necrosis in pancreatic beta cells.
• These effects lead to early beta cell dysfunction and impaired insulin production.
• Findings suggest a link between microplastic exposure and increased susceptibility to diabetes, identifying MPs as potential metabolic disruptors.