Neuron function restored in brains damaged by Huntington’s disease using stem cells

June 20, 2012 - PRLog -- Researchers from Sweden, South Korea and the United States have collaborated on a project to restore neuron function to parts of the brain damaged by Huntington’s disease (HD) by successfully transplanting HD-induced pluripotent stem cells into animal models.

HD results from genetically programmed degeneration of nerve cells, called neurons, in certain areas of the brain.  This degeneration causes uncontrolled movements, loss of intellectual faculties, and emotional disturbance.  Specifically affected are cells of the basal ganglia, structures deep within the brain that have many important functions, including coordinating movement.  Within the basal ganglia, HD especially targets neurons of the striatum, particularly those in the caudate nuclei and the pallidum.  Also affected is the brain's outer surface, or cortex, which controls thought, perception, and memory.

Induced pluripotent stem cells (iPSCs) can be genetically engineered from human somatic cells such as skin, and can be used to model numerous human diseases.  They may also serve as sources of transplantable cells that can be used in novel cell therapies.  In this case, the patient provides a sample of his or her own skin to the laboratory.

In this collaborative study, experimental animals with damage to the striatum (an experimental model of HD) exhibited significant behavioral recovery after receiving transplanted stem cells.  Researchers hope that this approach eventually could be tested in patients for the treatment of HD.

Unique features of the iPSC approach means that the transplanted stem cells will be genetically identical to the patient’s and therefore no medications to prevent host-graft rejection will be needed, said Jihwan Song, PhD Associate Professor and Director of Laboratory of Developmental & Stem Cell Biology at CHA Stem Cell Institute, CHA University, Seoul, South Korea and co-author of the study.

The study, published in the journal Stem Cells, found that transplanted iPSCs initially formed neurons producing GABA, the chief inhibitory neurotransmitter in the mammalian central nervous system, which plays a critical role in regulating neuronal excitability and acts at inhibitory synapses in the brain.  GABAergic neurons, located in the striatum, are the cell type most susceptible to degeneration in HD.

Another key point in the study involves the new disease models for HD presented by this method, allowing researchers to study the underlying disease process in detail.  Being able to control disease development from such an early stage, using iPS cells, may provide important clues about the very start of disease development in HD.  An animal model that closely imitates the real conditions of HD also opens up new and improved opportunities for drug screening.

According to Dennis Lox, MD, a sports, physical and regenerative medicine specialist in the Tampa Bay area, stem cells appear to hold great promise in treating a variety of diseases and conditions.  Some conditions, such as joint, tendon and muscle injury, are treatable now with stem cells.  Other conditions, such as ALS, diabetes, heart disease and MS, appear to be treatable with stem cell therapy, but widespread treatment is still in the near-future.


http://www.DrLox.com