Biological effects of marine organisms
Pollutants of anthropogenic origin have also been polluting our oceans since the industrialization of the world. Coastal seas such as the North and Baltic Seas in particular have been and continue to be exposed to countless chemical inputs. Their concentrations in the marine environment are often inadequately documented and even if they are, there is a lack of data and knowledge on how to assess these concentrations in terms of their effect on organisms. We therefore investigate how certain chemicals affect organisms, at what concentrations in the environment the substances become harmful to health and how the cocktail of substances affects organisms. We also take into account additional stressors such as the warming of our oceans on the effect of individual pollutants or pollutant mixtures. In our funded projects, a particular focus is on the effects of toxic munition compounds on the marine environment of our seas.
Competences
We use biomarkers to assess the impact of pollutants on the health of marine organisms. We investigate effects at cell, tissue and organ level to assess the impact of certain chemicals. We are particularly interested in the assessment of long-term exposure to pollutants, even at low concentrations. We work with mussels in the laboratory and with mussels and fish in the field.
Pollutants can attack an organism at different levels. In the case of short exposure times and low concentrations, the first reactions occur at the molecular level. If the exposure continuous or the concentrations of pollutants are high, detoxification measures may break down and metabolic disturbances occur. In case exposure is ongoing fist tissue alterations and later also diseases manifest. We use biomarkers to indicate these effects at the molecular, cellular, tissue or organ levels. Per definition biomarker are measurable indicators that reflect the biological status of an organism.
Methods
Pollutants my produce reactive oxygen species (ROS) in cells of exposed organisms. ROS disturb metabolic processes by reacting with all kind of cell molecules. As a protection measure enzymes of the anti-ox-defence system are produced helping to neutralising ROS.
Method to measure activities of anti-ox defence enzymes:
Histology and biomarker assessment:
If the oxidative stress exceeds the cellular defence, cell organelle impairments and metabolic disturbances occur and metabolic end products accumulate. These impairments and disturbances are assessed using different Biomarkers. Most biomarkers deployed in our labs are based on deep frozen cryo sections stained or tested using different SOP protocols. Together with the anti-ox-enzyme activity, the biomarker results provide information about the metabolic status, organ functions and health status of an organism.
Method for biomarker evaluation:
Histology applying light microscopy und Transmission Electron Microscopy (TEM)
We examine organs using classic histological methods. This involves making and embedding tissue sections and evaluating them with the help of contrast staining. This allows to detect tissue alterations, diseases and tumors. In addition, we apply TEM microscopy to elucidate cell morphologic structures as well cytoplasmatic structures. By applying antigen and antibody reaction in combination with TEM the localisation of pollutants on cellular level is possible.
Tools
- Tecan-Reader – Analysis of enzyme activities, e.g. anti-ox-defence enzymes as first level response to pollutants (in cooperation with WG Aquaculture).
- Cryo-Sectioning – Production of tissue cryo-section for test of cell organelle or malfunctioning of metabolic processes.
- Rotations-Microtom – Histologic tissue analysis.
- Image Analyse – Computer unterstütze Bildanalyse von Geweben.
- TEM transmission electron microscope - Structural analysis of plant and animal cells as well as for detection and localization of pollutants on cell level (in cooperation with WG Bionic).