In vitro exposure to PM2.5 of olfactory Ensheathing cells and SH-SY5Y cells and possible association with neurodegenerative processes.

PM2.5 exposure represents a risk factor for the public health. PM2.5 is able to cross the blood-alveolar and blood-brain barriers and reach the brain through three routes: nasal olfactory pathway, nose-brain pathway, blood-brain barrier pathway. We evaluated the effect of PM2.5 to induce cytotoxicity and reduced viability on in vitro cultures of OECs (Olfactory Ensheathing Cells) and SH-SY5Y cells. PM2.5 samples were collected in the metropolitan area of Catania, and the gravimetric determination of PM2.5, characterization of 10 trace elements and 16 polycyclic aromatic hydrocarbons (PAHs) were carried out for each sample. PM2.5 extracts were exposed to cultures of OECs and SH-SY5Y cells for 24-48-72 h, and the cell viability assay (MTT) was evaluated. Assessment of mitochondrial and cytoskeleton damage, and the assessment of apoptotic process were performed in the samples that showed lower cell viability. We have found an annual average value of PM2.5 = 16.9 µg/m3 and a maximum value of PM2.5 = 27.6 µg/m3 during the winter season. PM2.5 samples collected during the winter season also showed higher concentrations of PAHs and trace elements. The MTT assay showed a reduction in cell viability for both OECs (44%, 62%, 64%) and SH-SY5Y cells (16%, 17%, 28%) after 24-48-72 h of PM2.5 exposure. Furthermore, samples with lower cell viability showed a decrease in mitochondrial membrane potential, increased cytotoxicity, and also impaired cellular integrity and induction of the apoptotic process after increased expression of vimentin and caspase-3 activity, respectively. These events are involved in neurodegenerative processes and could be triggered not only by the concentration and time of exposure to PM2.5, but also by the presence of trace elements and PAHs on the PM2.5 substrate. The identification of more sensitive cell lines could be the key to understanding how exposure to PM2.5 can contribute to the onset of neurodegenerative processes.

Microplastics (≤ 10 µm) bioaccumulation in marine sponges along the Moroccan Mediterranean coast: Insights into species-specific distribution and potential bioindication.

Microplastics (MPs) are pervasive in marine environments and widely recognized as emerging environmental pollutants due to the multifaceted risks they exert on living organisms and ecosystems. Sponges (Phylum Porifera) are essential suspension-feeding organisms that may be highly susceptible to MPs uptake due to their global distribution, unique feeding behavior, and sedentary lifestyle. However, the role of sponges in MP research remains largely underexplored. In the present study, we investigate the presence and abundance of MPs (≤10 µm size) in four sponge species, namely Chondrosia reniformis, Ircinia variabilis, Petrosia ficiformis, and Sarcotragus spinosulus collected from four sites along the Mediterranean coast of Morocco, as well as their spatial distribution. MPs analysis was conducted using an innovative Italian patented extraction methodology coupled with SEM-EDX detection. Our findings reveal the presence of MPs in all collected sponge specimens, indicating a pollution rate of 100%. The abundance of MPs in the four sponge species ranged from 3.95×105 to 1.05×106 particles per gram dry weight of sponge tissue, with significant differences observed among sampling sites but no species-specific differences. These results imply that the uptake of MPs by sponges is likely influenced by aquatic environmental pollution rather than the sponge species themselves. The smallest and largest MPs were identified in C. reniformis and P. ficiformis, with median diameters of 1.84 µm and 2.57 µm, respectively. Overall, this study provides the first evidence and an important baseline for the ingestion of small MP particles in Mediterranean sponges, introducing the hypothesis that they may serve as valuable bioindicators of MP pollution in the near future.

Effects of Nano and Microplastics on the Inflammatory Process: In Vitro and In Vivo Studies Systematic Review.

BACKGROUND: Microplastics (MPs) and Nanoplastics (NPs) are plastic fragments that spread in the environment and accumulate in the human body, so they have been becoming a worldwide environmental concern because of their potential human health effects. The aim of this systematic review was to investigate the prospective impact of MPs and NPs on the inflammatory process. METHODS: Electronic article search was performed on PubMed, Scopus and Web of Science international databases from 1 Jan 2012 to 31 Dec 2021. Screenings of titles, abstracts and full texts were performed according to the Preferred Reporting Item for Systematic Review and Meta-analyses (PRISMA). The methodological quality of the studies was checked by the Toxicological data Reliability Assessment Tool. RESULTS: Electronic article search identified 125 records, from which 6 in vitro, 11 in vivo and 2 both in vivo and in vitro studies were included. Both in vivo and in vitro studies have showed an increase ofdifferent inflammatory outcomes (Interleukines, Tumor necrosis factor, Chemokines, Interferones, Transcription factors, Growth factors, Oxydoreductase, Proteins and others), thus it seems to confirm the association withthe exposure to microplastics of different types, sizes, exposure times and exposed species. CONCLUSIONS: This systematic review seems to support the relationship between the exposure to MPs and the inflammatory processboth in vivo and in vitro. Greater caution is needed about the role of NPs because ofa very small number of studies. Additional high-quality studies are warranted to confirm these results, especially the research should be focused on NPs being lacking literature.

Possible association between PM2.5 and neurodegenerative diseases: A systematic review.

Air pollution is one of the most serious environmental problems that afflict our planet and one of the greatest risk factors for human health. In particular, PM2.5 is able to cross the blood-alveolar and blood-brain barriers, thus increasing the onset of respiratory, cardiovascular and neurodegenerative diseases. Neurodegenerative disease is a progressive neuronal dysfunction that leads to neuronal lesions in both structure and function, and includes several diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), vascular dementia (VaD), multiple sclerosis (MS), and others. We carried out a systematic review using PRISMA approach to investigate on the possible association between exposure to PM2.5 and neurodegenerative diseases. The international databases (PubMed, Science Direct, Web of Sciences) were used to find published studies on the topic. The search period was between January 2011 and June 2021. About 2000 full research articles were selected, and finally, we included 20 full-research articles. Selected studies have highlighted how PM2.5 exposure can be associated with the onset of neurodegenerative diseases (AD, PD, MS, VaD). This association depends not only on age, PM2.5 levels and exposure time, but also on exposure to other air pollutants, proximity to areas with high vehicular traffic, and the presence of comorbidities. Exposure to PM2.5 promotes neuroinflammation processes, because through breathing the particles can reach the nasal epithelial mucosa and transferred to the brain through the olfactory bulb. Furthermore, exposure to PM2.5 has been associated with an increased expression of markers of neurodegenerative diseases (e.g. alpha-synuclein or beta-amyloid), which can contribute to the etiopathogenesis of neurodegenerative diseases. Although many studies have revealed the pathological relationship between PM2.5 exposure and cognitive impairment, the potential cellular and molecular mechanisms of PM2.5 leading to neurodegenerative disease remain not entirely clear, and then, further studies need to be carried out on the topic.

Microplastics in fillets of Mediterranean seafood. A risk assessment study.

Microplastics (MPs) are considered as emergent threat to human health. No complete data still exists on MPs presence in fish tissue and their transmission to humans. The present study aims to detect and quantify the presence of MPs (<3 µm) in several edible seafood (Sardina pilchardus, wild and farmed Sparus aurata, Mullus surmuletus, Solea solea and musselMytilus galloprovincialis) from the south coast of Mediterranean Sea. MPs were detected through an innovative extraction method coupled to the SEM-EDX technology. The Estimated Daily Intakes (EDIs) for adults and children for each species were calculated. The higher median level (IQR) of MPs (9.09E+04) was found inM. surmuletus. Conversely, the lower median (IQR) level was observed in S. pilchardus (7.04E+04). The smallest and biggest median (IQR)diameter of MPs (1.8 and 2.5 µm) were identified in M. galloprovincialisand S. solea, respectively. The highest EDIs (25.50E+03; 48.09E+03) arefor ingestion of farmedS. auratarespectively for adults and children. Instead, the lowest EDIs (2.37E+02; 4.48E+02) are due to M. galloprovincialisingestion for adults and children, respectively. Our data should be carefully considered in view of the direct exposure of humans to plastic particles under 3 µm through seafood consumption to better manage the related risks.

Embryotoxicity of polystyrene microplastics in zebrafish Daniorerio.

In the recent years, increasing scientific and societal concern has been raised over the presence and accumulation of plastic debris in the environment and the effects of microplastics (MPs) that can easily interact with biota. In order to elucidate the impact of MPs at the critical development stages of freshwater fish species, a fish embryo toxicity test was herein performed on the zebrafish Danio rerio, exposed to 10 µm polystyrene MPs at 200 particles/mL for 120 hpf. After exposure, accumulation of MPs in larvae was measured, survival, hatching and larvae development were monitored and the oxidant/anti-oxidant responses and cellular detoxification evaluated. No impact on survival of developing zebrafish was revealed, but a moderate delay in hatching was observed. Alterations in larvae development were recorded with zebrafish exhibiting serious deformities, mainly at the level of column and tail, as well as a compromised integrity of the visual structure of the eyes. Moreover, increased levels of gene transcription involved in the oxidative stress (sod1, sod2 and cat) and in cellular detoxification (gst and cyp) were also detected in MPs-exposed zebrafish larvae. Overall, this research work provides new insights on the ecotoxicological impact of polystyrene MPs on the critical developmental stages of a freshwater fish species, therefore enhancing the current knowledge of the environmental risk posed by MPs to the aquatic ecosystem.