ParkC’s laboratory research: cell replacement therapies and prevention of degeneration
A long held dogma that the adult brain does not contain stem cells or generate new neurons has been disarmed (Gage, 2002). It is now accepted that there are at least two brain regions in the adult mammalian brain in which stem cells are found (the subventricular zone and hippocampus). These stem cells can proliferate and generate new neurons (neurogenesis) to replace those that are lost as part of the natural aging process (Gage, 2002).
In neurodegenerative diseases, such as Parkinson’s, there is an imbalance between neurogenesis and the rate of cell death (Fahn and Sulzer, 2004). The characteristic Parkinson’s symptoms result when a group of cells (called dopamine producing neurons) in the brain die. To date, there is no way of halting the continual death of these cells hence people with Parkinson’s progressively deteriorate. Medications treat the symptoms and with time become ineffective. However, the progressive deterioration of people with Parkinson’s could be halted or reversed if the imbalance between cell death and neurogenesis could be restored.
There are essentially two approaches to remedy this situation:
- replace the cells that have died either by increasing the rate of neurogenesis and/or cell replacement therapies; and
- decrease or stop the degeneration of neurons.
Understanding the response of genes in either of these scenarios is a particular focus of our laboratory research.
Cell replacement therapies are an innovative treatment approach that aim to repair the underlying damage by replacing the cells that have died. Typically, the source of replacement cells is immature cells (i.e. stem cells) as they can survive when transplanted into the adult brain and can be directed to develop into the required dopamine producing neurons.
A major hurdle to the success of this treatment option has been the discrepancy in turning immature cells into dopamine producing neurons in the controlled laboratory environment compared to the dynamic and poorly understood conditions of the degenerative adult brain.
To improve the outcome of this treatment approach it is essential that the process of turning immature cells into dopamine producing neurons can be controlled and maximised. Our research is aimed at achieving this by investigating the interaction between the immature cells and the environment that they mature in.
A further hurdle is the delivery of stem cells or protective agents. To this end, we work in collaboration with neurosurgeon Chris Lind to optimise surgical delivery systems.
ECU PhD Student, Ms Maria Albertsen
ECU PhD Student, Ms Alesya Drozdova
UWA Masters Student, Mr Mark Lam
ECU Honours Student, Ms Tiza Chipungu
UWA Honours Student, Ms Syerna Ong