Biochemical responses of the mussel Perna perna after exposure to environmental concentrations of the UV filter Benzophenone-3.

Personal care products, such as UV filters, are frequently present in aquatic ecosystems, but studies on their impact on marine organisms are still scarce. Here we addressed the effects of benzophenone-3 (BP-3) on the antioxidant status of Perna perna mussels exposed to concentrations of 0.1 and 3 µg.L-1 for 72 h and 7 days. Glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PDH) activity and lipoperoxidation (MDA) were evaluated in the gills. A significant reduction (p < 0.05) in the activity of G6PDH and GPx was observed after exposure for 7 days to 0.1 µg.L-1. However, no significant differences were observed in GST activity and MDA levels, independently of the exposure time. Principal component analysis (PCA) showed an association of BP-3 highest concentration with GR and MDA at 72 h and only with GR at 7 days of exposure. Similarly, the integrated biomarker response (IBR) demonstrated GR and MDA alterations. In conclusion, environmentally relevant concentrations of BP-3 altered antioxidant and auxiliary enzymes, which could cause long-term damage to P.perna mussels. The need to implement more efficient techniques in wastewater treatment systems is pointed out, especially in summer, when UV filters are used more frequently and abundantly.

Field study of metal concentrations and biomarker responses in resident oysters of an estuarine system in southern Brazil.

Pollutant exposure is considered an important factor responsible for the decline in marine biodiversity of Latin American coastal ecosystems. This threat has been detected in an estuarine system in southern Brazil, which prompted an investigation into the long-term biological effects of a chronic metal contamination on resident oysters from the Laguna Estuarine System (LES). Here, we present the species- and size-specific variations of biomarker responses (catalase, glucose-6-phosphate dehydrogenase, glutathione S-transferase, and protein carbonylation) in the gills and digestive gland of Crassostrea gigas and Crassostrea gasar. In parallel, concentrations of eight metals (Al, Cd, Cr, Cu, Fe, Mn, Pb, Zn) in soft tissues were measured. Our analyses revealed that the metal levels exhibited decreasing order in both species: Zn > Fe > Al > Cu > Mn > Cd. Except for Cu and Al, metal concentrations did not differ between oyster species. Biomarker results highlighted that C. gasar presented higher antioxidant responses, whereas C. gigas showed increased biotransformation upon exposure to LES pollutants, which varied according to the tissue. However, C. gasar showed a significant higher content of protein carbonylation but was not related to metals. In our research approach, the observation of metals presence and biomarkers-related responses are considered biologically relevant from an ecotoxicological perspective and serve as a baseline for future pollution studies in estuaries of Latin America. Finally, we recommend adopting a suite of biomarkers in both C. gasar and C. gigas, regardless their size and weight, as sentinel organisms in future regional biomonitoring studies in southern Brazil.

Hsp70 expression in shrimp Litopenaeus vannamei in response to IHHNV and WSSV infection.

The effects of environmental changes, on non-target organisms may impact and bring consequences at the molecular level in marine organisms. There is a lack of data supporting the hypothesis according to which environmental stress modulates the immune system, leading to an increased susceptibility to infectious agents in shrimps. The present study was focused on changes occurring in cellular defense proteins in Litopenaeus vannamei infected by virus infection hypodermal and hematopoietic necrosis (IHHNV) and white spot syndrome (WSSV). Western blot analysis was used to evaluate expression of protein Hsp70, in gill tissue. Up-regulation levels were supported by immune detection analysis, suggesting that IHHNV and WSSV-shrimp infection promotes changes in the expression of these proteins.