An innovative team of Japanese scientists have been leading a trial in monkeys aimed at restoring their damaged nerve cells. The cells are damaged in a similar way to that caused to human cells that are exposed to Parkinson’s disease.
When Parkinson’s disease onsets; a progressive loss of the nerve cells that are responsible for releasing dopamine will occur. Dopamine is vital as it helps human’s control their body movements.
The group of researchers select macaque monkeys to conduct the experiment. It began with triggering a nerve cell loss mimicking that that occurs in a human body with Parkinson’s disease.
They then used human stem cells to try and trigger the replacement of the cells lost in the macaque monkeys’ bodies. The monkeys had precursor dopamine neurons derived from human stem cells transplanted into their brains and after two years, showed a very positive improvement in cell regeneration.
To create these replacement cells, known as induced pluripotent stem (iPS) cells, ordinary adult cells are genetically reprogrammed and reverted back to an embryonic-like state. This state allows them to be coaxed to later develop into different types of adult cells, specifically in this experiment – developing into the dopamine neurons that were previously removed from the monkeys.
The BBC recently described researcher Prof Jun Takahashi of Kyoto University’s reaction to the astounding findings of the experiment. The most fundamental discovery was that the quality of the “artificial” neurons produced from stripping down human cells to allow them to develop into iPS cells, was just as high as that of the functionality the cells naturally produced by monkeys’ brains. Takahashi explained, “because iPS cells are easy to obtain, we can standardise them to only use the best iPS cells for therapy.”
Dr Tilo Kunath, a Parkinson’s UK-funded researcher at the Medical Research Council Centre for Regenerative Medicine at the University of Edinburgh told the BBC that “this is extremely promising research demonstrating that a safe and highly effective cell therapy for Parkinson’s can be produced in the lab. Such a therapy has the potential to reverse the symptoms of Parkinson’s in patients by restoring their dopamine-producing neurons. The next stage will be to test these therapies in a first-in-human clinical trial.”
While scientists don’t believe that this discovery will provide a solution to other aspects of Parkinson’s disease that are not related to the inability to control movement, such as falling and dementia, the Japanese team is hopeful to begin iPS cell generation testing on humans by the end of 2018.
This is a glimmer of hope for those affected by Parkinson’s disease as well as their loved ones.