Researchers have tested a new drug in a mouse model of Parkinson’s disease, which can make immune cells protect dopamine-producing cells instead of attacking them.
The results are good as they provide a bridge between the immune system and nerve cell protection in Parkinson’s disease.
Senior author Howard Gendelman, a professor of pharmacology and experimental neuroscience at UNMC said that the idea for the drug was born around 10 years ago, when it was realized the type of white blood cells was attacking the brain cells that can develop Parkinson’s disease.
He said that the new Longevity Biotech drug (LBT-3627) was able to alter the cells function from killing the nerve cells to protect them. The death of dopamine-producing cells in a part of the brain termed as the substantia nigra pars compacta is a primary sign of Parkinson’s disease. Dopamine sends brain signals to control a number of functions including movement.
With the progress of the brain-wasting disease, patients will lose their ability to walk, talk and take care of themselves.
Scientists know that Parkinson’s disease involves altering both dopamine and non-dopamine brain cells and their signaling pathways, plus inflammatory changes to microglia and infiltration of T lymphocytes.
Initially, they thought the microglia and the white blood cells were the result of injury. But later a decade ago, researchers have found that both activated microglia and white blood cells play a crucial role in play an important role in neurodegeneration in Parkinson’s disease.
Other studies show that the immune system can protect and attack the brain. The experimental drug LBT-3627 is similar to a naturally occurring and anti-inflammatory molecule termed as VIP that works for a range of disorders.
Nonetheless, there are problems with new drugs on VIP- one is it degrades in the body and the other reason is unable to distinguish between its two intended receptors- VPAC1 and VPAC2.
Receptors receive signals from outside the cell. They bind to particular molecules called agonists. Drug developers use this feature to make agonist drugs that can alter the behavior of cells.
LBT-3627 differs from VIP in two aspects: it targets to VPAC2 and lasts longer than VIP in the body before degrading.
When researchers tested LBT-3627 in a mouse model of Parkinson’s disease, they found that it achieve 80% protection of dopamine-producing cells. The team found that the drug effect the microglia cells and they are responsible for the protective effect that stops the brain damage.
Prof. Gendelman states that the a particular set of white blood cells are produced as a result of LBT-3627 treatment and provided protection of dopamine-producing nerve cells from being despaired. The neurotoxic immune reaction stops progressing and LBT-3627 was able to prevent disease.
Notably, there are around 10 million people across the globe living with Parkinson’s disease-around 1 million of them are in the US where around 60,000 people are diagnosed with the disease each year.
Another sign of Parkinson’s disease is the accumulation and progressive spread of protein clumps called Lewy bodies in the brain affected by loss of dopamine cells. Few scientists think that the protein clumps increase the risk of disease.