Nanoplastics: From tissue accumulation to cell translocation into Mytilus galloprovincialis hemocytes. resilience of immune cells exposed to nanoplastics and nanoplastics plus Vibrio splendidus combination

Abstract

Background Few studies have examined nano-sized plastic particulates (NPs) exposure in relation to oxidative stress and biochemical responses in rodents, commonly used for toxicity evaluations on which to base risk assessment for humans. Methods Here we explored possible oxidative stress and biochemical responses of ve weeks oral exposure to polystyrene (PS) nanoparticles (1, 3, 6 and 10 mg/kg body weight per day) in male rats. We used variance analysis and variance explained statistic eta-squared (2) to estimate the strength of relationships worked out. The whole body scanning further provided insight into the bio-distribution of nanoplastics upon oral exposure. Results Results demonstrated the accumulation of PS-NPs through whole body and also a dose-dependent increase in the production of reactive oxygen species (ROS). Signi cant alterations in antioxidant responses including serum levels of catalase, superoxide dismutase (SOD), and total glutathione content were noticed, pointing towards a perturbation of redox state induced by the exposure conditions. Acetylcholinesterase level in highest dose group was about 40 percent lower than those in control group. Biochemical parameters viz. glucose, cortisol, lipase, lactate, lactate dehydrogenase (LDH), alkaline phosphatase, gamma-glutamyl transpeptidase (GGT), triglycerides, and urea showed a signi cant increase, while total protein, albumin and globulin levels showed an appreciable decline. Conclusion The pattern of associations noticed with AChE activity and biochemical responses in our study suggests the possibility that a neurobehavioral effect or dysfunctions in energy metabolism, or both, may be the potential mode of action, possibly through stress response as well as liver function. Perturbations of creatinine and uric acid levels are indeed plausible biological explanations for the association with kidney dysfunction. Although we provided a new scienti c clue for exploring the biological effects of plastics nanoparticles, the results warrant additional research with a larger sample size. The suggested potential mechanisms also remains to be investigated. 10 5.78 c 2.8 c 2.97 c 15.25 b 21.75 d 25.75 b 205 b 510.25 d 123 c 55.13 c 162.75 b *Different letters for the signi cances demonstrate that there are signi cant differences among groups (p < 0.05).

Microplastics, microfibres and nanoplastics cause variable sub-lethal responses in mussels (Mytilus spp.)

“…Efforts to quantify PS-NP within mussel tissues was unsuccessful, as we were unable to distinguish the red fluorescence signal of the particles from autofluorescence. However, we remain confident that uptake occurred given our observations of active feeding, and evidence from other research papers that PS-NP (either free-floating or aggregated with microalgae) can be filtered-out by mussels; in these studies, PS-NP uptake was ascertained by measuring reduction of nanoparticle concentrations in the surrounding water and/or visualising uptake of PS-NP within tissues via fluorescence imaging (Brandts et al, 2018a;Sendra et al, 2019;Wegner et al, 2012), although such imaging studies have been criticised as leaching of fluorophores may give false positives (Catarino et al, 2019). identified per mg of digestive gland tissue of individual mussels, following 24 h or 7-day exposure to 500 ng mL -1 microplastics.…”

Behavior and Bio-Interactions of Anthropogenic Particles in Marine Environment for a More Realistic Ecological Risk Assessment

“…Furthermore, trophic transfer of plain PS NPs of different sizes (30, 100, and 500 nm) from mussels to the crab Carcinus maenas has been demonstrated under laboratory conditions (Farrell and Nelson, 2013). Some studies reported the ability of PS NPs to translocate from the hemolymph to target tissues in benthic invertebrates (Farrell and Nelson, 2013) in a size-dependent manner, with 50 nm of PS NPs more internalized by hemocytes than larger particles (Sendra et al, 2019a), taken up in immune cells, and cause oxidative stress, immunotoxicity, and genotoxicity (Canesi et al, 2015;Brandts et al, 2018;Bergami et al, 2019;Ciacci et al, 2019;Sendra et al, 2019a). In a recent study on the benthic foraminifer Ammonia parkinsoniana, plain PS NPs tested at a concentration of 1 µg ml −1 were internalized in the single-cell marine eukaryotes within 24 h, enhancing freeradical production and accumulation of intracellular neutral lipids (Ciacci et al, 2019).…”

Polystyrene nanoplastics accumulate in ZFL cell lysosomes and in zebrafish larvae after acute exposure, inducing a synergistic immune response in vitro without affecting larval survival in vivo

“…11 Moreover, PS-NPs have been previously found to interfere with the immune system of zebrafish 8,10,12 as well as other aquatic species. 13,14 In D. rerio, PS-NPs have been shown to upregulate the expression of inflammatory cytokines, 8 activate the complement system and oxidative stress mechanisms 10 and provoke DNA damage, induced by ROS and apoptosis. 11 In this context, we seek to address the question of whether their interaction with the immune system can affect the survival of populations in their natural environments, where organisms are frequently exposed to pathogens.…”

“…To our knowledge, barely any studies on the combination of PS-NPs and an immune challenge have been performed. In a recent study, Sendra et al 14 evaluated the response of Mytilus galloprovincialis haemocytes in vitro when infected with Vibrio splendidus, following an exposure to PS-NPs. They reported that the invertebrate's haemocytes showed resilience when infected with the bacteria, being able to recover their phagocytic capacity.…”