We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microplastics as vectors for microcystin-LR: Enhanced bioavailability, oxidative damage, and immune dysregulation in zebrafish spleen
Summary
Researchers studied the combined effects of the algal toxin microcystin-LR and polystyrene microplastics on zebrafish spleen over 60 days. They found that microplastics enhanced the bioavailability of the toxin, worsening oxidative damage and suppressing immune function beyond what either pollutant caused alone. The study suggests that microplastics can act as vectors for harmful algal toxins, amplifying their biological impact in aquatic organisms.
The co-occurrence of eutrophication and plastic pollution has emerged as a critical global water quality challenge. In the present study, we systematically investigated the joint effects of microcystin-LR (MC-LR) and polystyrene microplastics (PSMPs) on antioxidant defense mechanisms and innate immunity function through an orthogonal experimental design (MC-LR: 0, 0.8, 4, 20 μg/L; PSMPs: 0, 100 μg/L). After 60 d exposure, our results found that the presence of PSMPs enhanced the MC-LR bioavailability in the spleen of zebrafish. Besides, the severity of splenic injuries exhibited a concentration-dependent response to MC-LR exposure and was further exacerbated in co-exposure groups, primarily manifested with increased melano-macrophage centers and mitochondrial edema. Compared to the MC-LR-only group, the MC-LR-co-PSMPs exposure groups showed remarkably increased malondialdehyde (MDA) content, indicating enhanced oxidative damage. These results were further supported by significantly reduced glutathione (GSH) levels and downregulated gpx1a mRNA expression. Simultaneously, co-exposure to MC-LR and PSMPs significantly decreased complement C3 content and downregulated the transcriptional level of c3b, il1β and ifn in relative to the single MC-LR exposure groups, which indicated that they could jointly result in immune inhibition. Our results revealed that PSMPs significantly enhanced MC-LR bioavailability in the spleen, functioning as vectors that exacerbated splenic histopathological damage, oxidative stress as well as immune dysfunction. These findings highlight the non-negligible combined toxicity of these pollutants in eutrophic aquatic systems.
Sign in to start a discussion.
More Papers Like This
Microcystin-LR and polystyrene microplastics jointly lead to hepatic histopathological damage and antioxidant dysfunction in male zebrafish
This study exposed zebrafish to a common water toxin (microcystin-LR) both alone and combined with polystyrene microplastics, and found that the microplastics made the liver damage significantly worse. The microplastics acted as carriers, increasing how much toxin accumulated in the fish liver and amplifying oxidative stress. This is relevant to human health because it shows microplastics can boost the harmful effects of other pollutants commonly found in drinking water sources.
Polystyrene microplastics enhance microcystin-LR-induced cardiovascular toxicity and oxidative stress in zebrafish embryos
Zebrafish embryos exposed to both microplastics and microcystin-LR (a toxin produced by algal blooms) developed significantly worse heart and blood vessel damage than those exposed to the toxin alone. The microplastics amplified oxidative stress and cell death, suggesting that in polluted waterways where both contaminants coexist, the combined health risks may be greater than either one individually.
Polystyrene microplastics enhance the microcystin-LR-induced gonadal damage and reproductive endocrine disruption in zebrafish
Zebrafish exposed to polystyrene microplastics along with microcystin-LR (a common toxin from algae blooms) suffered worse reproductive damage than when exposed to either pollutant alone. The microplastics acted as carriers that increased the amount of toxin accumulating in the fish's reproductive organs. This study demonstrates that microplastics can worsen the effects of other water pollutants by helping toxic chemicals build up in the body.
The presence of polystyrene nanoplastics enhances the MCLR uptake in zebrafish leading to the exacerbation of oxidative liver damage
Researchers found that polystyrene nanoplastics enhanced the uptake of the toxin microcystin-LR in zebrafish liver over three months of co-exposure, exacerbating oxidative damage and cellular swelling compared to microcystin exposure alone.
Influence of microplastics on the accumulation and chronic toxic effects of cadmium in zebrafish (Danio rerio)
Researchers exposed zebrafish to polystyrene microplastics combined with cadmium for three weeks and found that the presence of microplastics significantly increased cadmium accumulation in the liver, gut, and gills. The combined exposure caused greater oxidative damage, tissue inflammation, and disruption of protective gene activity than either pollutant alone. The study demonstrates that microplastics can enhance the toxicity of heavy metals in fish by acting as carriers that increase the body's uptake of harmful substances.