Stem Cell Research Sheds Light on Genetic Factor in Bipolar Disorder
A study published last month in a journal called Translational Psychiatry entitled “Transcripts involved in calcium signaling and telencephalic neuronal fate are altered in induced pluripotent stem cells from bipolar disorder patients” reported interesting findings about the development of brain cells in people with bipolar disorder compared to controls — people without bipolar disorder. The study was unique in two important ways:
- The study was based on the increasingly accepted concept that even subtle changes in early embryonic brain development can cause symptoms of mental illness that appear later in life.
- The researchers took advantage of evolving technology that creates stem cells — the origin cells in embryos that evolve into all the different cells types in the body — from adults rather than taking them from embryos. This allows researchers to have access to many more stem cells and also offers the opportunity to compare the stem cells from adults with certain diseases to those without and to see differences in the way they develop.
Growing Neurons from Stem Cells
The researchers took skin cells from three people with bipolar disorder and two controls. These cells are placed in culture dishes and reprogrammed into stem cells called induced pluripotent stem cells or iPsc’s. These cells then began the process of turning into the many different types of cells in the human body.
Cells that were beginning to turn into neurons — brain cells — were selected and then further grown and observed using a variety of laboratory techniques to measure genetic expression and cell behaviors.
Differences in Neurons Grown from Bipolar and Control Stem Cells
Neurons that grew from bipolar stem cells showed significant differences in their gene expression profile from the neurons that grew from the control stem cells:
- Neurons grown from bipolar stem cells expressed more membrane receptor genes and more genes related to calcium signaling than the control group. Other types of studies have strongly suggested that differences in membrane receptors and calcium signaling are important underlying processes in bipolar disorder.
- Compared to the control neurons, the bipolar neurons also showed different growth patterns — in particular which subtypes of neurons they tended to become. These developmental patterns may be extremely important in understanding the way brains become vulnerable to bipolar disorder.
Important Note: Genes Not the Only Cause
Of note is that this research is looking at gene expression in adults with bipolar disorder. This does not in any way mean that the genes are the only cause. While genetics is thought to account for about 80% of the cause of bipolar disorder, there remain many unknown factors including environmental triggers in particular physical and emotional stressors on the body. This study is not examining any of these important factors.
New Technology Opening New Frontiers for Bipolar Research
This is an exciting study that uses new technology to try to understand the neurologic changes underlying bipolar disorder. While this research is still preliminary and needs to be expanded and replicated, it represents a new line of study that offers new frontiers for understanding how the brains of people with bipolar disorder develop and operate differently from those of people without bipolar. Ultimately this information will be central in evolving more accurate and effective tools for diagnosis as well as treatment options.
Exploring the Neurological Beginnings of Bipolar Disorder
I am particularly interested in the developmental angle here — the awareness that the neurologic beginnings of illnesses that present later in life may well be in place from the earliest developmental stages of brain formation. I think that this offers us a more accurate and useful understanding of mental illness and is optimistic in terms of developing early diagnostic tools and perhaps even ultimately ways to prevent the onset of these devastating conditions.
Fink, C. (2014). Stem Cell Research Sheds Light on Genetic Factor in Bipolar Disorder. Psych Central. Retrieved on July 31, 2015, from http://blogs.psychcentral.com/bipolar/2014/04/stem-cell-research-sheds-light-genetic-factor-bipolar-disorder/