The Re-classification and Developments of Parkinson’s Disease

By Rebeca Funes

Parkinson’s disease (PD) is a progressive neurological disorder that primarily affects the body’s movement. An international study was led by China’s Changping Laboratory in collaboration with Washington University School of Medicine (WashU Medicine) in St. Louis and others on Feb. 4th on PD. Although there’s no cure for this disorder, this study found groundbreaking information that can bring major changes to how Parkinson’s is diagnosed and treated. 

“Studying Parkinson’s disease is incredibly important, whether that be the disease itself or its treatments. It’s good that researchers and scientists are putting in the work to find information on it, especially since it affects so many people,” said Ricardo Camera, a junior at MLEC.

The study points to a specific brain network as the core of Parkinson’s. This region of the brain, called the somato-cognitive action network, also known as SCAN, was first recognized in 2023 at WashU Medicine by Nico U. Dosenbach, professor of neurology at WashU Medicine. SCAN seemed to connect thinking with movements. Dosenbach concluded that SCAN is responsible for our movements, digestion, sleep, and different cognitions. 

Parkinson’s has a broad range of symptoms, going even further than just movement issues, but also causing cognitive impairment, dementia, sleep disorders, etc and affects more than around 10 million worldwide. Thus, Dosebach and other researchers wanted to investigate whether an abnormality in SCAN could explain Parkinson’s. They were able to do this through an experimental therapy involving over 800 participants across multiple institutions in the U.S and China.

Patients with PD received deep brain stimulation (DBS), which is a surgical procedure that involves implanting electrodes in specific areas of the brain to deliver electrical impulses, or non-invasive treatments such as transcranial magnetic stimulation (TMS), which uses magnetic fields to stimulate nerve cells in the brain.

Healthy individuals with motor issues were also included in the study as controls. Researchers then gathered the brain imaging of these patients to analyze. The analysis revealed that “Parkinson’s disease is characterized by hyperconnectivity between the SCAN and subcortex”. The subcortex is responsible for emotion, memory, and motor control. Additionally, the four therapies used within the study that lowered the connectivity between the SCAN and subcortex worked more effectively than traditional methods for improving symptoms.

“I think targeting SCAN to treat Parkinson’s can potentially cure it. Although more research would have to be put into it, at the very least, targeting this region of the brain can revolutionize treatment for patients with Parkinson’s disease,” stated Huzaifa Khan, a senior at MLEC.

With this research, Parkinson’s disease can be better treated. “This reclassification of PD shifts the focus from complex and diverse phenotypic symptoms to specific circuit pathologies, encouraging future research on the associations between network dysfunction and the various symptom domains of PD,” stated in the study by multiple researchers: Jianxun Ren, Wen Zhang, Louisa Dahmani, et al.

Phenotypical symptoms are observable traits or characteristics of an individual. It is often related to their genetics and environment. Furthermore, researchers have developed a new precision treatment system designed to specifically target SCAN. In a clinical trial, there was a 56% response rate after two weeks in 18 patients who received the treatment, targeting TMS.

Dosenbach is planning to test non-invasive treatments involving surface electrode strips placed over SCAN regions of the brain to treat gait dysfunction in patients with PD, according to Medicine.Washu.edu. Gait is the process of walking that includes the coordinated interactions between the brain and the body. 

This discovery on Parkinson’s disease can transform the way it is identified and treated. Knowing that PD targets a specific brain network, better treatments can be developed to alleviate those suffering from it. Although these findings do need further research, they can potentially mean that researchers are on the right track in finding a cure for PD.