Scientists identify 'clean-up' snafu that kills brain cells in Parkinson's disease

March 3, 2013, Albert Einstein College of Medicine

Researchers at Albert Einstein College of Medicine of Yeshiva University have discovered how the most common genetic mutations in familial Parkinson's disease damage brain cells. The study, which published online today in the journal Nature Neuroscience, could also open up treatment possibilities for both familial Parkinson's and the more common form of Parkinson's that is not inherited.

Parkinson's disease is a gradually progressing disorder of the nervous system that causes stiffness or slowing of movement. According to the Parkinson's Disease Foundation, as many as one million Americans are living with the disease.

The most common mutations responsible for the familial form of Parkinson's disease affect a gene called leucine-rich repeat kinase-2 (LRRK2). The mutations cause the LRRK2 gene to code for abnormal versions of the LRRK2 protein. But it hasn't been clear how LRRK2 mutations lead to the defining microscopic sign of Parkinson's: the formation of aggregates inside dopamine-producing nerve cells of the brain.

"Our study found that abnormal forms of LRRK2 protein disrupt an important garbage-disposal process in cells that normally digests and recycles unwanted proteins including one called – the main component of those that gunk up nerve cells in Parkinson's patients," said study leader Ana Maria Cuervo, M.D., Ph.D., professor of developmental and molecular biology , of anatomy and , and of medicine and the Robert and Renee Belfer Chair for the Study of at Einstein.

The name for the disrupted disposal process is chaperone-mediated autophagy (the word "autophagy" literally means "self-eating"). It involves specialized molecules that "guide" old and damaged proteins to enzyme-filled structures called lysosomes; there the proteins are digested into amino acids, which are then recycled within the cell.

"We showed that when LRRK2 inhibits chaperone-mediated autophagy, alpha-synuclein doesn't get broken down and instead accumulates to toxic levels in ," said Dr. Cuervo.

The study involved mouse neurons in tissue culture from four different animal models, neurons from the brains of patients with Parkinson's with LRRK2 mutations, and neurons derived from the skin cells of Parkinson's patients via induced pluripotent stem (iPS) cell technology. All the lines of research confirmed the researchers' discovery.

"We're now looking at ways to enhance the activity of this recycling system to see if we can prevent or delay neuronal death and disease," said Dr. Cuervo. "We've started to analyze some chemical compounds that look very promising."

Dr. Cuervo hopes that such treatments could help patients with familial as well as nonfamilial Parkinson's – the predominant form of the disease that also involves the buildup of alpha-synuclein.

Dr. Cuervo is credited with discovering chaperone-mediated autophagy. She has published extensively on autophagy and its role in numerous diseases, such as cancer and Huntington's disease , and its role in age-related conditions, including organ decline and weakened immunity. Dr. Cuervo is co-director of Einstein's Institute of Aging Research.

Explore further: Blocking LRRK2 activity is not a simple answer to Parkinson's disease

More information: The paper is titled "Interplay of LRRK2 with chaperone-mediated autophagy."

Related Stories

Blocking LRRK2 activity is not a simple answer to Parkinson's disease

May 29, 2012
Mutations in the LRRK2 gene are the most common cause of genetic Parkinson's disease (PD). New research published in BioMed Central's open access journal Molecular Neurodegeneration demonstrates that loss of function of LRRK2 ...

Recommended for you

Parkinson's disease 'jerking' side effect detected by algorithm

January 8, 2018
A mathematical algorithm that can reliably detect dyskinesia, the side effect from Parkinson's treatment that causes involuntary jerking movements and muscle spasms, could hold the key to improving treatment and for patients ...

New brainstem changes identified in Parkinson's disease

January 4, 2018
A pioneering study has found that patients with Parkinson's disease have more errors in the mitochondrial DNA within the brainstem, leading to increased cell death in that area.

Caffeine level in blood may help diagnose people with Parkinson's disease

January 3, 2018
Testing the level of caffeine in the blood may provide a simple way to aid the diagnosis of Parkinson's disease, according to a study published in the January 3, 2018, online issue of Neurology, the medical journal of the ...

Researchers shed light on why exercise slows progression of Parkinson's disease

December 22, 2017
While vigorous exercise on a treadmill has been shown to slow the progression of Parkinson's disease in patients, the molecular reasons behind it have remained a mystery.

Robotic device improves balance and gait in Parkinson's disease patients

December 19, 2017
Some 50,000 people in the U.S. are diagnosed with Parkinson's disease (PD) every year. The American Institute of Neurology estimates there are one million people affected with this neurodegenerative disorder, with 60 years ...

New findings point to potential therapy for Parkinson's Disease

December 19, 2017
A new study, published in Proceedings of the National Academy of Sciences (PNAS), sheds light on a mechanism underlying Parkinson's disease and suggests that Tacrolimus—an existing drug that targets the toxic protein interaction ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.