Assessing the Impact of Polyethylene Nano/Microplastic Exposure on Human Vaginal Keratinocytes

Abstract

The global rise of single-use throw-away plastic products has elicited a massive increase in the nano/microplastics (N/MPLs) exposure burden in humans. Recently, it has been demonstrated that disposable period products may release N/MPLs with usage, which represents a potential threat to women’s health which has not been scientifically addressed yet. By using polyethyl ene (PE) particles (200 nm to 9 μm), we showed that acute exposure to a high concentration of N/MPLs induced cell toxicity in vaginal keratinocytes after effective cellular uptake, as viability and apoptosis data suggest, along with transmission electron microscopy (TEM) observations. The internalised N/MPLs altered the expression of junctional and adherence proteins and the organisation of the actin cortex, influencing the level of genes involved in oxidative stress signalling pathways and that of miRNAs related to epithelial barrier function. When the exposure to PE N/MPLs was discontinued or became chronic, cells were able to recover from the negative effects on viability and differentiation/proliferation gene expression in a few days. However, in all cases, PE N/MPL exposure prompted a sustained alteration of DNA methyltransferase and DNA demethylase expression, which might impact epigenetic regulation processes, leading to accelerated cell ageing and inflammation, or the occurrence of malignant transformation.

Adverse Effects of Micro- and Nanoplastics on Humans and the Environment

“…Moreover, chronic exposure to these particles caused lasting alterations in DNA methyltransferases and demethylases, potentially impacting epigenetic regulation, aging, inflammation, and even malignant transformations. These findings underscore the toxic effects of N/MPLs on human keratinocytes and underline the importance of comprehensively evaluating the plastics used in hygiene products, especially for women, such as disposable period products [14]. N/MPLs also pose a substantial risk to the endocrine system by interfering with hormone production, release, transport, metabolism, and elimination.…”

“…The detrimental effects of MPL absorption through the skin due to extensive contact with plastic particles from sources like dust, cosmetics, sanitary pads, and liquid hand cleansers is an area of ongoing investigation [12,13]. In this regard, it was found that the acute exposure of vaginal keratinocytes to N/MPLs resulted in cell toxicity, affecting viability, apoptosis, gene expression, oxidative stress pathways, and miRNAs [14]. Moreover, chronic exposure to these particles caused lasting alterations in DNA methyltransferases and demethylases, potentially impacting epigenetic regulation, aging, inflammation, and even malignant transformations.…”

Antitumour effects of SFX-01 molecule in combination with ionizing radiation in preclinical and in vivo models of rhabdomyosarcoma

“…To evaluate the presence of autophagosomes, autolysosomes or other vacuolar structures, we performed transmission electron microscopy (TEM) experiments, as previously described [ 42 ]. Briefly, RH30 and RD cells treated with SFX-01 (10–20 µM) or DMSO for 72 h were fixed in 2% glutaraldehyde (Electron Microscopy Sciences, Hatfield, PA, USA) in 0.1 M PBS for 24 h at + 4 °C.…”

Connecting the Dots: Livestock Animals as Missing Links in the Chain of Microplastic Contamination and Human Health

“…At the same time, dermal/skin contact needs to be considered because primary MPs, which are intentionally produced, were detected in products that people use daily such as cosmetics, toothpaste, skincare products, and even disposable period products [42,43]. However, ingestion is usually considered to be the primary route of exposure to microand nanoplastics.…”