Stereological estimation of cell numbers in the basal ganglia of postmortem brain tissue from schizophrenic patients with and without medical treatment
The purpose of the research project is to make use of stereological methods as well as molecular biological techniques to investigate disease relevant brain regions, including central gray structures, in post-mortem brains of schizophrenic patients and control subjects. We will include brains from untreated and treated schizophrenic patients, in order to determine possible effects of medication.
The project has been approved by the Regional Ethics Committee of the Capital Region of Denmark.
Estimation of the total number of cells (neurons, oligodendrocytes, astrocytes and microglia) in the basal ganglia of the brain using stereological counting methods.
We have identified and obtained 13 brains as well as associated autopsy reports from non-medicated schizophrenic patients (died before 1952) in the brain collection at SDU. In addition, we have identified and prepared 12 brains from age- and gender-matched controls from our own brain bank at Bispebjerg Hospital. As the autopsy report from the schizophrenic patients does not contain detailed clinical information (e.g. any other medical treatment or diseases that may affect the CNS), the relevant medical records were obtained from the National Archives (Viborg, Odense and Copenhagen), scanned and analyzed.
We have also:
- Performed a detailed visual inspection of the formalin-fixed tissue so that brains without intact central regions (due to previous pathological examinations) are omitted. We are able to use 11 out of 13 schizophrenic brains, corresponding to ~ 85%.
- Sectioned the central brain regions into 40-μm thin consecutive sections. This is done exhaustively and gives approximately 1000 sections per. brain when collecting every sixth section. Until now this is completed in 6 out of 11 schizophrenic brains, corresponding to ~ 55%.
- Giemsa-stained a fraction of the sections in each brain to verify the usability for volume estimation and cell identification. In 4 out of 6 schizophrenic brains we are able to identify the neurons (corresponding to 67%) and in 2 out of 6 brains there are identifiable glial cells (corresponding to 33%).
Based on the numbers above, we will thus be able to quantify the neurons in ~ 57% and the glial cells in ~ 28% of the brains from schizophrenic patients without medical treatment (formalin fixed >70 years).
Conclusions
We are able to complete the current project, but not within the specified time frame of the application. This is partly due to the characteristic of the tissue and the susceptibility to staining, which means that only a relatively small number of the obtained brains can be used. A stereological estimation of the neurons is possible, whereas counting of the glial cells will be subjected to particularly great uncertainty.
In addition to the above, we have participated in the dissemination of the project and the Brain Collection at SDU on DRTV (Lægens Bord). We have been in contact with Weekendavisen (Podcast - Lone Frank) and are currently in dialogue with Susanne Michi Gargiulo (CNN) and Gloria Mediehus (Podcast - København Kommunes Social psykiatri).
Example of differentiation of Giemsa staining in a section of the brains. From the left: not useful for cell counting; can be used for neuro-counting; can be used for neuron and glial counting.