Nanoparticles decrease the byssal attachment strength of the thick shell mussel Mytilus coruscus

Mapping the intellectual structure and emerging trends for the application of nanomaterials in gastric cancer: A bibliometric study

BACKGROUND

Recent reviews have outlined the main nanomaterials used in relation to gastrointestinal tumors and described the basic properties of these materials. However, the research hotspots and trends in the application of nanomaterials in gastric cancer (GC) remain obscure.

AIM

To demonstrate the knowledge structure and evolutionary trends of research into the application of nanomaterials in GC.

METHODS

Publications related to the application of nanomaterials in GC were retrieved from the Web of Science Core Collection for this systematic review and bibliometric study. VOSviewer and CiteSpace were used for bibliometric and visualization analyses.

RESULTS

From 2000 to 2022, the application of nanomaterials in GC developed rapidly. The keyword co-occurrence analysis showed that the related research topics were divided into three clusters: (1) The application of nanomaterials in GC treatment; (2) The application and toxicity of nanomaterials in GC diagnosis; and (3) The effects of nanomaterials on the biological behavior of GC cells. Complexes, silver nanoparticles, and green synthesis are the latest high-frequency keywords that represent promising future research directions.

CONCLUSION

The application of nanomaterials in GC diagnosis and treatment and the mechanisms of their effects on GC cells have been major themes in this field over the past 23 years.

Perfluorooctanoate and nano titanium dioxide impair the byssus performance of the mussel Mytilus coruscus

Perfluorooctanoate (PFOA) is widely used as a surfactant and has metabolic, immunologic, developmental, and genetic toxicity on marine organisms. However, the effects of PFOA on individual defense functions in mussels in the presence of titanium dioxide nanoparticles (nano-TiO2) are poorly understood. To investigate the defense strategies and regulatory mechanisms of mussels under combined stressors, the thick-shell mussels Mytilus coruscus were exposed to different PFOA concentrations (0, 2 and 200 μg/L) and nano-TiO2 (0 and 0.1 mg /L, size: 25 nm) for 14 days. The results showed that, compared to the control group, PFOA and nano-TiO2 significantly reduced the number of byssal threads (NBT), byssal threads length (BTL), diameter of proximal threads (DPB), diameter of middle threads (DMB), diameter of distal byssal threads (DDB), adhesive plaque area (BPA), and breaking force of byssal threads (N). Under the influence of PFOA and nano-TiO2, the morphological surface smoothness of the fractured byssal threads surface increased, concurrently inducing an increased surface roughness in the adhesive plaques. Additionally, under the presence of PFOA and nano-TiO2, the foot displayed dispersed tissue organization and damaged villi, accompanied by an increased incidence of cellular apoptosis and an upregulation of the apoptosis gene caspase-8. Expression of the adhesion gene mfp-3 and byssal threads strength genes (preCOL-D, preCOL-NG) was upregulated. An interactive effect on the performance of byssal threads is observed under the combined influence of PFOA and nano-TiO2. Under co-exposure to PFOA and nano-TiO2, the performance of the byssal threads deteriorates, the foot structure is impaired, and the genes mRNA expression of byssal thread secretory proteins have compensated for the adhesion and byssal threads strength by up-regulation. Within marine ecosystems, organic and particulate contaminants exert a pronounced effect on the essential life processes of individual organisms, thereby jeopardizing their ecological niche within community assemblages and perturbing the dynamic equilibrium of the overarching ecosystem. ENVIRONMENTAL IMPLICATION: Perfluorooctanoic acid (PFOA) is prone to accumulate in marine organisms. TiO2 nanoparticles (nano-TiO2) are emerging environmental pollutants frequently found in marine environment. The effects of PFOA and nano-TiO2 on marine mussels are not well understood, and their toxic mechanisms remain largely unknown. We investigated the impacts of PFOA and nano-TiO2 on mussel byssus defense mechanisms. By assessing byssus performance indicators, morphological structures of the byssus, subcellular localization, and changes in byssal secretion-related genes, we revealed the combined effects and mechanisms through which these two types of pollutants may affect the functional capabilities and survival of mussels in the complex marine ecosystem.

Effects of nano-TiO2 and pentachlorophenol on the bioenergetics of mussels under predatory stress

Organic and nanoparticle pollutants are the main environmental problems affecting marine species, which have received great attention. However, the combined effect of pollutants on marine life in the presence of predators needs to be clarified. In this study, the effects of pentachlorophenol (PCP) and titanium dioxide nanoparticles (nano-TiO2) on the energy metabolism of mussels (Mytilus coruscus) in the presence of predators were assessed through cellular energy allocation (CEA) approach. Mussels were exposed to PCP (0, 1, and 10 μg/L), nano-TiO2 (1 mg/L, 25 and 100 nm), and predators (Portunus trituberculatus presence/absence) for 14 days. Exposure to high concentrations of PCP (10 μg/L) with small particle size nano-TiO2 (25 nm) decreased cellular energy stores (carbohydrates, lipids, and proteins) and increased cellular energy demand (measured as the activity of the mitochondrial electron transport system, ETS). During the first 7 days, energy was supplied mainly through the consumption of carbohydrates, while lipids are mobilized to participate after 7 days. The presence of predators caused a further decrease in energy stores. These findings demonstrate that PCP, nano-TiO2 and predators have a negative impact on energy metabolism at the cellular level. Carbohydrates are not able to meet the metabolic demand, lipids need to be consumed, and energy metabolism was also mediated by the involvement of proteins. Overall, our results suggest that PCP, nano-TiO2 and predators disrupt the cellular energy metabolism of mussels through reduced cellular energy allocation, small particles and predators drive mussels to exert energetic metabolic adjustments for detoxification reactions when toxic contaminants are present.

Dietary exposure to nTiO2 reduces byssus performance of mussels under ocean warming

Nano‑titanium dioxide (nTiO₂) is a widely used nanomaterial posing potential ecological risk for marine ecosystems that might be enhanced by elevated temperatures such as expected during climate change. nTiO₂ may affect benthic filter feeders like mussels through waterborne exposures and via food chain due to the adsorption on/in algae. Mussel byssus are proteinaceous fibers secreted by byssal glands of the mussels for attachment. Byssus production and mechanical properties are sensitive to environmental stressors but the combined effects of warming and nTiO₂ on byssus performance of mussels are unclear hampering our understanding of the predation and dislodgement risk of mussels under the multiple stressor scenarios. We explored the effects of a short-term (14-day) single and combined exposures to warming (28 °C) and 100 μg L^-1 nTiO₂ (including food co-exposure) on the byssus performance of the thick shell mussel Mytilus coruscus. The mechanical strength (measured as the breaking force) of the byssal threads was impaired by warming and nTiO₂ (including food co-exposure), but the number and length of the byssal threads were increased. The mRNA expression levels of mussel foot proteins (mfp-3, mfp-5) and pre-collagens (preCOL-D, preCOL-P, preCOL-NG) were up-regulated to varying degrees, with the strongest effects induced by warming. This indicates that the physiological and molecular mechanisms of byssus secretion are plastic. However, downregulation of the mRNA expression of preCOL-D and preCOL-P under the combined warming and nTiO₂ exposures indicate the limits of these plasticity mechanisms and suggest that the attachment ability and survival of the mussels may be impaired if the pollution or temperature conditions further deteriorate.

Impacts of marine heatwaves on byssus production in highly invasive fouling mussels

Marine heatwaves (MHWs) are projected to increase in their frequency, intensity, and duration, causing irreversible and catastrophic consequences for intertidal ecosystems around the world. The highly invasive fouling mussel, Arcuatula senhousia, can cause marked habitat alteration by constructing extremely intense byssal mats, devastating the biodiversity of many intertidal systems, yet very little is known about its fate under conditions of more frequent, hotter and longer MHWs. Here, we assessed impacts of two scenarios of MHWs (low-intensity with 4 °C rise of seawater temperature and high-intensity with 8 °C rise, respectively) on the byssal production of A. senhousia. Mussels exposed to low-intensity MHWs did not show any significant differences in the number, length and diameter of byssal threads, compared with those not thermally stressed. Under high-intensity scenario, the byssus production was significantly depressed, and byssal threads became fewer, shorter and finer, in line with significant decreases in cumulative length and volume. These findings provide a better understanding of responses of invasive fouling mussels such as A. senhousia to MHWs and make a leap forward in linking climate change and biological fouling in marine ecosystems.

Environmental impacts due to the use of sunscreen products: a mini-review

Sunscreen use has increased in recent years, as sunscreen products minimize the damaging effects of solar radiation. Active ingredients called ultraviolet (UV) filters or UV agents, either organic or inorganic, responsible for defending skin tissue against harmful UV rays, are incorporated in sunscreen formulations. UV agents have a serious impact on many members of bio communities, and they are transferred to the environment either directly or indirectly. Many organic UV filters are found to be accumulated in marine environments because of high values of the octanol/water partition coefficient. However, due to the fact that UV agents are not stable in water, unwanted by-products may be formed. Experimental studies or field observations have shown that organic UV filters tend to bioaccumulate in various aquatic animals, such as corals, algae, arthropods, mollusks, echinoderms, marine vertebrates. This review was conducted in order to understand the effects of UV agents on both the environment and marine biota. In vivo and in vitro studies of UV filters show a wide range of adverse effects on the environment and exposed organisms. Coral bleaching receives considerable attention, but the scientific data identify potential toxicities of endocrine, neurologic, neoplastic and developmental pathways. However, more controlled environmental studies and long-term human use data are limited. Several jurisdictions have prohibited specific UV filters, but this does not adequately address the dichotomy of the benefits of photoprotection vs lack of eco-friendly, safe, and approved alternatives.

Impacts of four commonly used nanoparticles on the metabolism of a marine bivalve species, Tegillarca granosa

The rapid development of nanotechnology boosts the massive production and utilization of various nanoparticles (NPs). However, the NPs escaped into environments form emergent pollutants, which pose a potential threat to marine organisms and ecosystems. Due to their sessile filter-feeding lifestyle, marine bivalves live in pollution-prone coastal areas are more susceptible to land-sourced pollutants such as NPs. However, the impacts of many NPs on the metabolism, one of the most critical physiological processes of an organism, still remain largely unknown in bivalve species. To fill up this knowledge gap, in this study the impacts of four commonly used NPs (nZnO, nFe₂O₃, nCuO, and multi-walled carbon tube (MWCNT)) on the filtration rate, oxygen consumption rate, ammonia excretion rate, and O:N ratio were investigated in the blood clam, Tegillarca granosa. In addition, the expressions of ten key metabolism-related genes upon exposure to these NPs were also analyzed. The results demonstrated that exposure of blood clams to the NPs resulted in a reduction in the food intake (indicated by declined filtration rate), a shift in the metabolism substance, and disruptions in key metabolism-related molecular pathways (i.e., glycolysis and tricarboxylic acid cycle), which may render blood clam in energy shortage and thus pose significant threat to the health of this important bivalve species.

Microplastics aggravate the bioaccumulation of three veterinary antibiotics in the thick shell mussel Mytilus coruscus and induce synergistic immunotoxic effects

Marine bivalves living in pollution-prone coastal areas may be simultaneously coexposed to veterinary antibiotic residuals and microplastics (MPs). However, the synergistic effects of these two types of emergent pollutants have not been fully elucidated in mussel species. Therefore, the immunotoxic effects of the three representative antibiotics, oxytetracycline (OTC, 270 ng/L), florfenicol (FLO, 42 ng/L), and sulfamethoxazole (SMX, 140 ng/L), with and without the copresence of polystyrene MPs (0.26 mg/L, dimeter: 500 nm), were investigated in the thick shell mussel. Our data showed that the immunity was significantly hampered by exposure to the pollutants and MP-antibiotic coexposure induced synergistic immunotoxicity. For instance, compared to those treated with antibiotics (OTC, FLO, and SMX) alone, mussels coexposed to antibiotic and MPs had significantly lower phagocytic rate (further decline by approximately 28.80%, 34.21%, and 11.22%, respectively) and total hemocyte count (further reduced by approximately 37.45%, 61.67%, and 46.32%, respectively). Exposure to the pollutants tested also led to inductions in intracellular reactive oxygen species (ROS), decreases in the F-actin cytoskeleton, declines in the cell viability of hemocytes, and downregulation of cytoskeleton- and immune-related genes. In addition, mussels coexposed to antibiotic-MP accumulated significantly greater amounts of antibiotics, which may partially explain the synergic immunotoxic effect detected. Exposure to pollutants tested also led to suppression in the activity of glutathione-S-transferase (GST) and downregulation of detoxification-related genes whereas induction in the level of lipid peroxidation (indicated by MDA content) in gills, which may facilitate the entry whereas constrain the exclusion of antibiotics and therefore result in an elevation in accumulation of antibiotics.

Fine polystyrene microplastics render immune responses more vulnerable to two veterinary antibiotics in a bivalve species

Living in close proximity to the sediment of coastal areas, bivalves may be exposed to veterinary antibiotic residuals and microplastics (MPs) simultaneously. However, the immunotoxic impacts of veterinary antibiotics remain unknown in bivalves, let alone their interactions with MPs. Therefore, the immune responses of two representative veterinary antibiotics, oxytetracycline and florfenicol, was investigated in a bivalve species, the blood clam (Tegillarca granosa). The effects of the copresence of MPs on the immune responses triggered by these antibiotics were also analyzed. Results showed that exposure to antibiotics investigated led to significant alteration in hematic parameters and reduction in lectin content in serum. In addition to inducing ROS production, aggravating lipid peroxidation and DNA damage, and suppressing the hemocyte viability, antibiotic treatments also downregulated the expression of immune- and detoxification-related genes but upregulated apoptosis-related Caspase-3. Furthermore, the toxic impacts of antibiotics were found to be significantly increased by the copresence of MPs.

Effectiveness and Mechanisms of Recoverable Magnetic Nanoparticles on Mitigating Golden Mussel Biofouling

Mussel biofouling has become a problem in aquatic ecosystems, causing significant ecological impact and huge economic loss globally. Although several strategies have been proposed and tested, efficient and environment-friendly antifouling methods are still scarce. Here, we investigated the effects of recoverable magnetic ferroferric oxide nanoparticles (Fe₃O₄-NPs) with different sizes (10 and 100 nm), coatings (polyethylene glycol and polylysine), and concentrations (0.01 and 0.1 mg/L) on byssus adhesion-mediated biofouling by the notorious golden mussel Limnoperna fortunei. The results showed that magnetic Fe₃O₄-NPs, especially negatively charged polyethylene glycol-coated Fe₃O₄-NPs, size- and concentration-dependently reduced the byssus production, performance (breaking force and failure location), and adhesion rate. Further investigations on mechanisms showed that the down-regulation of foot protein 2 (Lffp-2) and energy-related metabolic pathways inhibited byssus production. The declined gene expression level and metal-binding ability of Lffp-2 significantly affected foot protein interactions, further reducing the plaque size and byssus performance. In addition, the change in the water redox state likely reduced byssus performance by preventing the interface interactions between the substrate and foot proteins. Our results confirm the effectiveness and underlying mechanisms of magnetic Fe₃O₄-NPs on mitigating L. fortunei biofouling, thus providing a reference for developing efficient and environment-friendly antifouling strategies against fouling mussels.