In vitro study on the toxicity of nanoplastics with different charges to murine splenic lymphocytes

2023

Environ. Sci. Technol.

Microplastics are emerging pollutants that have been widely reported in aquatic ecosystems. Based on the analysis of environmentally relevant concentrations of microplastics in global freshwater systems, herein, we employed aggregated-induced emission (AIE) microplastic fluorogens and imaged and quantified the bioaccumulation of differentially charged micro-(20 μm)/ nano-(200 nm) plastics (MNPs) in zooplankton Daphnia magna. We found that all particles of different sizes and charges were readily ingested, especially larger-sized and positively charged MNPs, with over 50% of the ingested particles accumulating in the gut. Bioaccumulation of MNPs reached 50% of steady-state condition within 1 h. The presence of algae inhibited the ingestion and depuration of MNPs. To further demonstrate the effects of such accumulation on gut health, we further applied the AIE probes for visualizing the pH and esterase in the digestive tract, as well as the gut inflammation. An accumulation of MNPs in D. magna significantly and rapidly induced the acidification of gut pH while inducing esterase activity. The NPs apparently induced gut inflammation in contrast to the MPs, demonstrating the size-dependent effects on oxidative stress. Our results highlighted that MNP exposure at environmentally relevant concentrations perturbed the microenvironments of zooplankton guts, which may significantly affect their digestion and assimilation of food materials as well as contaminant uptake.

Section: Resultsmentioning

confidence: 79%

Accumulation Kinetics and Gut Microenvironment Responses to Environmentally Relevant Doses of Micro/Nanoplastics by Zooplankton Daphnia Magna

2023

Environ. Sci. Technol.

“…MNPs can decrease cell viability, induce cell apoptosis, upregulate apoptosis-related protein expression, elicit ROS production, alter mitochondrial membrane potential, and dysregulate mitochondrial function in murine splenic lymphocytes [ 69 ].…”

Section: Toxicities Of Micro- and Nanoplastics On Mitochondriamentioning

confidence: 99%

Impact of Micro- and Nanoplastics on Mitochondria

Lee

Moon

et al. 2022

Metabolites

Mitochondria are highly dynamic cellular organelles that perform crucial functions such as respiration, energy production, metabolism, and cell fate decisions. Mitochondrial damage and dysfunction critically lead to the pathogenesis of various diseases including cancer, diabetes, and neurodegenerative and cardiovascular disorders. Mitochondrial damage in response to environmental contaminant exposure and its association with the pathogenesis of diseases has also been reported. Recently, persistent pollutants, such as micro- and nanoplastics, have become growing global environmental threats with potential health risks. In this review, we discuss the impact of micro- and nanoplastics on mitochondria and review current knowledge in this field.

“…Considering the fact that different charge properties of MPs − and foliar uptake contribute to the entry of MPs into plants, the toxicity effect of oppositely charged MPs on plant growth is worth investigating. Since plant cell walls are negatively charged due to deprotonated carboxylic groups, foliar uptake of differently charged MPs by plants may be variable.…”

Section: Introductionmentioning

confidence: 99%

Positively Charged Microplastics Induce Strong Lettuce Stress Responses from Physiological, Transcriptomic, and Metabolomic Perspectives

Xiang

et al. 2022

Environ. Sci. Technol.

Microplastics (MPs) can enter plants through the foliar pathway and are potential hazards to ecosystems and human health. However, studies related to the molecular mechanisms underlying the impact of foliar exposure to differently charged MPs to leafy vegetables are limited. Because the surfaces of MPs in the environment are often charged, we explored the uptake pathways, accumulation concentration of MPs, physiological responses, and molecular mechanisms of lettuce foliarly exposed to MPs carrying positive (MP+) and negative charges (MP–). MPs largely accumulated in the lettuce leaves, and stomatal uptake and cuticle entry could be the main pathways for MPs to get inside lettuce leaves. More MP+ entered lettuce leaves and induced physiological, transcriptomic, and metabolomic changes, including a decrease in biomass and photosynthetic pigments, an increase in reactive oxygen species and antioxidant activities, a differential expression of genes, and a change of metabolite profiles. In particular, MP+ caused the upregulation of circadian rhythm-related genes, and this may play a major role in the greater physiological toxicity of MP+ to lettuce, compared to MP–. These findings provide direct evidence that MPs can enter plant leaves following foliar exposure and a molecular-scale perspective on the response of leafy vegetables to differently charged MPs.