The Experts below are selected from a list of 195 Experts worldwide ranked by ideXlab platform

Claudia Wiegand - One of the best experts on this subject based on the ideXlab platform.

  • Molecular effects and bioaccumulation of levonorgestrel in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the nontarget Organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 mg L-1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 mg L-1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.

  • Exposure to human pharmaceuticals Carbamazepine, Ibuprofen and Bezafibrate causes molecular effects in Dreissena polymorpha
    Aquatic Toxicology, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Carbamazepine (CBZ), Ibuprofen (IBU) and Bezafibrate (BEZ) were tested for their potential to bioaccumulate and provoke molecular changes in the Non-Target Organism Dreissena polymorpha. mRNA changes of enzymes and other proteins involved in the prevention from protein damage (heat shock protein 70, hsp70) and oxidative stress (superoxide dismutase, SOD; catalase, CAT; metallothionein, MT), biotransformation (pi-class glutathione S-transferase, piGST; aryl hydrocarbon receptor, AH-R), elimination (P-glycoprotein, P-gp) and reversible protein posttranslational modification (protein phosphatase 2A, PP2A) served as molecular biomarkers. Mussels were exposed in a flow-through system to increasing concentrations of the three substances (1, 10, 100 and 1000 nM). The two lower concentrations correspond to environmentally relevant concentrations detected in surface and effluent waters, respectively. Measuring tissue concentration after one, four and seven days the uptake of CBZ and IBU by the mussels could be evidenced, whereas no accumulation data could be achieved for BEZ. The bioconcentration factor was highest for mussels exposed to the lowest CBZ and IBU concentrations, with 90 and 460-fold higher tissue concentration, respectively, after seven days. CBZ was the only substance tested which caused a significant increase in gill mRNA level of hsp70 after only one day exposure, evidencing the potential of CBZ to immediately provoke a stress condition and assumingly protein damage in gills. After longer exposure, mussels displayed down-regulated mRNA levels of hsp70 and SOD in gills, as well as of MT and P-gp in the digestive gland, hinting on an inhibitory character of CBZ. In IBU exposed mussels increased oxidant stress conditions were evidenced by induced mRNA levels in the digestive gland of CAT and MT, as well as SOD after one and four days, respectively. A concentration as found at sewage treatment plant effluents provoked an increase in transcript levels of piGST, suggesting enhanced need for biotransformation of IBU or by-products derived from oxidative stress. Also exposure to an environmentally relevant BEZ concentration provoked an immediate increase in piGST transcript level in the digestive gland followed by up-regulated hsp70 after four and seven days evidencing a chronic stress condition for the mussels.

  • The β-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha.
    Environmental pollution (Barking Essex : 1987), 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 microg L(-1)) of the beta-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

  • The beta-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 mg L1) of the b-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

Valeska Contardo-jara - One of the best experts on this subject based on the ideXlab platform.

  • Molecular effects and bioaccumulation of levonorgestrel in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the nontarget Organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 mg L-1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 mg L-1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.

  • Exposure to human pharmaceuticals Carbamazepine, Ibuprofen and Bezafibrate causes molecular effects in Dreissena polymorpha
    Aquatic Toxicology, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Carbamazepine (CBZ), Ibuprofen (IBU) and Bezafibrate (BEZ) were tested for their potential to bioaccumulate and provoke molecular changes in the Non-Target Organism Dreissena polymorpha. mRNA changes of enzymes and other proteins involved in the prevention from protein damage (heat shock protein 70, hsp70) and oxidative stress (superoxide dismutase, SOD; catalase, CAT; metallothionein, MT), biotransformation (pi-class glutathione S-transferase, piGST; aryl hydrocarbon receptor, AH-R), elimination (P-glycoprotein, P-gp) and reversible protein posttranslational modification (protein phosphatase 2A, PP2A) served as molecular biomarkers. Mussels were exposed in a flow-through system to increasing concentrations of the three substances (1, 10, 100 and 1000 nM). The two lower concentrations correspond to environmentally relevant concentrations detected in surface and effluent waters, respectively. Measuring tissue concentration after one, four and seven days the uptake of CBZ and IBU by the mussels could be evidenced, whereas no accumulation data could be achieved for BEZ. The bioconcentration factor was highest for mussels exposed to the lowest CBZ and IBU concentrations, with 90 and 460-fold higher tissue concentration, respectively, after seven days. CBZ was the only substance tested which caused a significant increase in gill mRNA level of hsp70 after only one day exposure, evidencing the potential of CBZ to immediately provoke a stress condition and assumingly protein damage in gills. After longer exposure, mussels displayed down-regulated mRNA levels of hsp70 and SOD in gills, as well as of MT and P-gp in the digestive gland, hinting on an inhibitory character of CBZ. In IBU exposed mussels increased oxidant stress conditions were evidenced by induced mRNA levels in the digestive gland of CAT and MT, as well as SOD after one and four days, respectively. A concentration as found at sewage treatment plant effluents provoked an increase in transcript levels of piGST, suggesting enhanced need for biotransformation of IBU or by-products derived from oxidative stress. Also exposure to an environmentally relevant BEZ concentration provoked an immediate increase in piGST transcript level in the digestive gland followed by up-regulated hsp70 after four and seven days evidencing a chronic stress condition for the mussels.

  • The β-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha.
    Environmental pollution (Barking Essex : 1987), 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 microg L(-1)) of the beta-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

  • The beta-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 mg L1) of the b-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

Werner Kloas - One of the best experts on this subject based on the ideXlab platform.

  • Molecular effects and bioaccumulation of levonorgestrel in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the nontarget Organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 mg L-1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 mg L-1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.

  • Exposure to human pharmaceuticals Carbamazepine, Ibuprofen and Bezafibrate causes molecular effects in Dreissena polymorpha
    Aquatic Toxicology, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Carbamazepine (CBZ), Ibuprofen (IBU) and Bezafibrate (BEZ) were tested for their potential to bioaccumulate and provoke molecular changes in the Non-Target Organism Dreissena polymorpha. mRNA changes of enzymes and other proteins involved in the prevention from protein damage (heat shock protein 70, hsp70) and oxidative stress (superoxide dismutase, SOD; catalase, CAT; metallothionein, MT), biotransformation (pi-class glutathione S-transferase, piGST; aryl hydrocarbon receptor, AH-R), elimination (P-glycoprotein, P-gp) and reversible protein posttranslational modification (protein phosphatase 2A, PP2A) served as molecular biomarkers. Mussels were exposed in a flow-through system to increasing concentrations of the three substances (1, 10, 100 and 1000 nM). The two lower concentrations correspond to environmentally relevant concentrations detected in surface and effluent waters, respectively. Measuring tissue concentration after one, four and seven days the uptake of CBZ and IBU by the mussels could be evidenced, whereas no accumulation data could be achieved for BEZ. The bioconcentration factor was highest for mussels exposed to the lowest CBZ and IBU concentrations, with 90 and 460-fold higher tissue concentration, respectively, after seven days. CBZ was the only substance tested which caused a significant increase in gill mRNA level of hsp70 after only one day exposure, evidencing the potential of CBZ to immediately provoke a stress condition and assumingly protein damage in gills. After longer exposure, mussels displayed down-regulated mRNA levels of hsp70 and SOD in gills, as well as of MT and P-gp in the digestive gland, hinting on an inhibitory character of CBZ. In IBU exposed mussels increased oxidant stress conditions were evidenced by induced mRNA levels in the digestive gland of CAT and MT, as well as SOD after one and four days, respectively. A concentration as found at sewage treatment plant effluents provoked an increase in transcript levels of piGST, suggesting enhanced need for biotransformation of IBU or by-products derived from oxidative stress. Also exposure to an environmentally relevant BEZ concentration provoked an immediate increase in piGST transcript level in the digestive gland followed by up-regulated hsp70 after four and seven days evidencing a chronic stress condition for the mussels.

  • The β-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha.
    Environmental pollution (Barking Essex : 1987), 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 microg L(-1)) of the beta-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

  • The beta-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 mg L1) of the b-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

Gunnar Nutzmann - One of the best experts on this subject based on the ideXlab platform.

  • Molecular effects and bioaccumulation of levonorgestrel in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the nontarget Organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 mg L-1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 mg L-1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.

  • Exposure to human pharmaceuticals Carbamazepine, Ibuprofen and Bezafibrate causes molecular effects in Dreissena polymorpha
    Aquatic Toxicology, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Carbamazepine (CBZ), Ibuprofen (IBU) and Bezafibrate (BEZ) were tested for their potential to bioaccumulate and provoke molecular changes in the Non-Target Organism Dreissena polymorpha. mRNA changes of enzymes and other proteins involved in the prevention from protein damage (heat shock protein 70, hsp70) and oxidative stress (superoxide dismutase, SOD; catalase, CAT; metallothionein, MT), biotransformation (pi-class glutathione S-transferase, piGST; aryl hydrocarbon receptor, AH-R), elimination (P-glycoprotein, P-gp) and reversible protein posttranslational modification (protein phosphatase 2A, PP2A) served as molecular biomarkers. Mussels were exposed in a flow-through system to increasing concentrations of the three substances (1, 10, 100 and 1000 nM). The two lower concentrations correspond to environmentally relevant concentrations detected in surface and effluent waters, respectively. Measuring tissue concentration after one, four and seven days the uptake of CBZ and IBU by the mussels could be evidenced, whereas no accumulation data could be achieved for BEZ. The bioconcentration factor was highest for mussels exposed to the lowest CBZ and IBU concentrations, with 90 and 460-fold higher tissue concentration, respectively, after seven days. CBZ was the only substance tested which caused a significant increase in gill mRNA level of hsp70 after only one day exposure, evidencing the potential of CBZ to immediately provoke a stress condition and assumingly protein damage in gills. After longer exposure, mussels displayed down-regulated mRNA levels of hsp70 and SOD in gills, as well as of MT and P-gp in the digestive gland, hinting on an inhibitory character of CBZ. In IBU exposed mussels increased oxidant stress conditions were evidenced by induced mRNA levels in the digestive gland of CAT and MT, as well as SOD after one and four days, respectively. A concentration as found at sewage treatment plant effluents provoked an increase in transcript levels of piGST, suggesting enhanced need for biotransformation of IBU or by-products derived from oxidative stress. Also exposure to an environmentally relevant BEZ concentration provoked an immediate increase in piGST transcript level in the digestive gland followed by up-regulated hsp70 after four and seven days evidencing a chronic stress condition for the mussels.

  • The β-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha.
    Environmental pollution (Barking Essex : 1987), 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 microg L(-1)) of the beta-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

  • The beta-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 mg L1) of the b-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

Stephan Pflugmacher - One of the best experts on this subject based on the ideXlab platform.

  • Molecular effects and bioaccumulation of levonorgestrel in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the nontarget Organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 mg L-1) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 mg L-1) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage.

  • Exposure to human pharmaceuticals Carbamazepine, Ibuprofen and Bezafibrate causes molecular effects in Dreissena polymorpha
    Aquatic Toxicology, 2011
    Co-Authors: Valeska Contardo-jara, Claudia Lorenz, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Carbamazepine (CBZ), Ibuprofen (IBU) and Bezafibrate (BEZ) were tested for their potential to bioaccumulate and provoke molecular changes in the Non-Target Organism Dreissena polymorpha. mRNA changes of enzymes and other proteins involved in the prevention from protein damage (heat shock protein 70, hsp70) and oxidative stress (superoxide dismutase, SOD; catalase, CAT; metallothionein, MT), biotransformation (pi-class glutathione S-transferase, piGST; aryl hydrocarbon receptor, AH-R), elimination (P-glycoprotein, P-gp) and reversible protein posttranslational modification (protein phosphatase 2A, PP2A) served as molecular biomarkers. Mussels were exposed in a flow-through system to increasing concentrations of the three substances (1, 10, 100 and 1000 nM). The two lower concentrations correspond to environmentally relevant concentrations detected in surface and effluent waters, respectively. Measuring tissue concentration after one, four and seven days the uptake of CBZ and IBU by the mussels could be evidenced, whereas no accumulation data could be achieved for BEZ. The bioconcentration factor was highest for mussels exposed to the lowest CBZ and IBU concentrations, with 90 and 460-fold higher tissue concentration, respectively, after seven days. CBZ was the only substance tested which caused a significant increase in gill mRNA level of hsp70 after only one day exposure, evidencing the potential of CBZ to immediately provoke a stress condition and assumingly protein damage in gills. After longer exposure, mussels displayed down-regulated mRNA levels of hsp70 and SOD in gills, as well as of MT and P-gp in the digestive gland, hinting on an inhibitory character of CBZ. In IBU exposed mussels increased oxidant stress conditions were evidenced by induced mRNA levels in the digestive gland of CAT and MT, as well as SOD after one and four days, respectively. A concentration as found at sewage treatment plant effluents provoked an increase in transcript levels of piGST, suggesting enhanced need for biotransformation of IBU or by-products derived from oxidative stress. Also exposure to an environmentally relevant BEZ concentration provoked an immediate increase in piGST transcript level in the digestive gland followed by up-regulated hsp70 after four and seven days evidencing a chronic stress condition for the mussels.

  • The β-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha.
    Environmental pollution (Barking Essex : 1987), 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 microg L(-1)) of the beta-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.

  • The beta-receptor blocker metoprolol alters detoxification processes in the Non-Target Organism Dreissena polymorpha
    Environmental Pollution, 2010
    Co-Authors: Valeska Contardo-jara, Stephan Pflugmacher, Gunnar Nutzmann, Werner Kloas, Claudia Wiegand
    Abstract:

    Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to Non-Target Organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 mg L1) of the b-blocker metoprolol in a flow-through system for seven days. The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations.