Mustafa(pbuh) Prize News

Royan Scientists a Step Closer to Parkinson Cell Therapy

2026/06/17

MSTF Media reports:
Hossein Baharvand, a stem cell and developmental biologist and director of Royan Institute for Stem Cell Biology and Technology, is a known figure in Stem Cell research not only in his home country, Iran, but all around the world. In the 90s, Baharvand, along with a few up-and-coming researchers, took the first strides in stem cell-related research, a path he has ever since been treading with rigor.
Part of Baharvand’s research focused on treating Parkinson's disease and age-related macular degeneration (AMD), a noteworthy work which was noticed by the judges of the Mustafa^(pbuh) Prize. Thus, in 2019, he was selected as one of the Mustafa^(pbuh) Prize laureates from Islamic countries. 
A significant part of Baharvand and his colleagues' research is dedicated to investigating the possibility of using stem cells to treat neurological diseases, especially Parkinson's, a disease that millions of people around the world grapple with and for which no certain treatment is yet known.
Understanding the mechanism of this disease and finding ways to replace lost nerve cells is one of the major research areas in the field of regenerative medicine. To better grasp the importance of this research, one must first become acquainted with the nature of Parkinson's disease and what happens in the brains of patients.

Parkinson’s disease
To better understand the state of the brain and diseases like Parkinson's, one can think of the human body as analogous to a powerful computer.

When we buy a new laptop, everything--from the smell of the packaging to the image quality and the performance of the device--works perfectly. However, over time and with constant use, problems gradually surface; the keyboard starts glitching, the hard drive won’t work, or the battery malfunctions.
Just like an electronic device wears out over time, the human body also deteriorates in terms of its functioning as it ages. One of the most important components of this powerful machine is the brain. The human brain acts like the CPU or central processing unit in a computer, and its proper functioning is essential for the smooth functioning of all parts of the body. Baharvand emphasizes that just as it is impossible to imagine a computer without a CPU, it is unimaginable to think of a body without a brain.
Just as a CPU is made up of complex and extensive electronic circuits, the brain is not just a simple monolithic organ but is made up of a very complex network of components and connections. The Mustafa^(pbuh) Prize laureate explained that without these amazing complexities and intricate connections between parts of the body, life would not be possible.
Chemicals play an undeniable part in brain function. Dopamine, for instance, has a big say in how the body functions. Dopamine is a neurotransmitter, a chemical that allows neurons, or nerve cells, to communicate with each other throughout the body. According to Baharvand, these endogenous chemicals play a fundamental role in many everyday functions.
Involved in numerous functions as it is, including memory, movement, motivation, mood, attention, and many other processes, dopamine’s increased or decreased levels are associated with diseases such as Parkinson's, restless legs syndrome, and attention deficit hyperactivity disorder. Parkinson's, a familiar name though it is, presents patients with difficult and complex consequences.
Parkinson's is a neurological disorder that is caused primarily by the destruction of dopamine-producing neurons in an area of the brain called the substantia nigra, or SN. This part of the brain helps control body movements by producing dopamine.
The initial symptoms of Parkinson's might be tremors that may not be noticeable at first. These tremors may appear in only one hand or sometimes in one leg or even in the jaw. Baharvand identifies slurred speech and swallowing problems as other symptoms of the disease, which usually intensify over time.
The exact cause of Parkinson's is not yet known. Estimates show that about 10 percent of cases could be due to genetics, while about 90 percent of cases fall into the category of idiopathic, or of unknown causes.
Currently, Parkinson's is recognized as a progressive neurological disorder for which there is no definitive cure. However, there are methods to control the symptoms and improve patients' quality of life, which can have varying effectiveness depending on each individual’s circumstances.
One of the most common treatment methods is the use of medications that aim to regulate dopamine levels in the brain to help reduce symptoms of the disease. In addition to drug therapy, methods such as "deep brain stimulation" have also been studied. DBS is a method that involves implanting electrodes within areas of the brain to produce electrical impulses that affect brain activity. Baharvand noted that a lot of these methods are not viable options for many patients.
Patients’ brains are analogous to systems that need repairing. One possible solution is to perform superficial and quick repairs without carefully examining the overall structure of the device; an approach that is akin to drug therapy for Parkinson's.
Although this method can alleviate some symptoms, it is not able to repair the damaged nerve structure. According to Baharvand, such treatment is like basic repairs that only allow limited use of the computer, without fixing the underlying problem in the system.
Another option, complicated and costly as it is, involves taking the damaged device to a specialist who knows the particular structure of the system and its internal communications like the back of his/her hand and can restore its original functionality.
In the field of Parkinson's treatment, such a role is played by "cell therapy." It is an approach that aims to repair damaged parts of the brain and restore its functional abilities.
Using stem cells in Parkinson’s treatment is like carrying out professional computer repair. These cells have the ability to develop into new dopamine-producing neurons and replace lost neurons. He emphasized that unlike drug therapy, which only improves superficial function, cell therapy focuses on the fundamental restoration of key components.
Stem cells have the ability to reprogram and differentiate into specialized cell types, making them a suitable option for producing dopamine-producing neurons. According to Baharvand, researchers have also been using these cells to create laboratory models of Parkinson's disease to examine the mechanisms of the disease and the effectiveness of drugs more closely.
These efforts are a pivotal step towards gaining a better grasp of the disease and developing new treatment methods. The approach of replacing damaged neurons with stem cells is one of the main focuses of modern research in the treatment of Parkinson's.
The goal of this method is to restore motor function in the brain by transplanting new dopamine-producing cells. This approach, however, presents its own challenges. High costs, ethical considerations related to the source of cells, and most importantly, biosafety requirements are among the major challenges in the development of this treatment method. Safety in this field means ensuring the health and stability of cells after transplantation so that their growth is controlled and there are no risks of uncontrolled division or tumorigenesis.
Despite the numerous complexities and challenges, the potential of these cells provides researchers with a strong incentive to continue research. Baharvand added that one of the main focuses of his team’s research is to investigate and improve safety in the use of stem cells to treat Parkinson's.
Given the capacity of stem cells to differentiate into specialized cell types, including dopamine-producing neurons, meticulous direction of the differentiation pathway of these cells is of critical importance. Bahravand noted that the goal is to produce only the desired cells, namely dopamine-producing neurons, and to prevent unwanted differentiation into other cell types.
Uncontrolled cell growth can lead to the formation of tumors, and therefore careful control of this process is essential to ensure biosafety.
To produce specialized neurons, researchers use human embryonic stem cells, which are highly capable of differentiating into functional cell types and are therefore an excellent choice for producing dopamine-producing neurons. In the future, these cells could replace lost neurons in the brains of Parkinson's patients.
Acquiring a deeper understanding of the precise characteristics of the primary stem cells and the final desired cells significantly helps gain better control over the differentiation, a process that, according to Baharvand, can be considered a type of “negotiation with cells.” In other words, researchers direct the differentiation of cells towards a specific result by adjusting environmental and molecular conditions. The goal is for the cells to not only grow properly, but also to become the exact type of cell needed for the treatment.
There are two main problems in the process of differentiating stem cells into dopamine-producing neurons. First, some cells remain in intermediate stages of differentiation and do not fully grow into specialized cells. These cells do not have a clear functional identity, as if they have not received the message directing differentiation correctly.
The second problem is referred to as "false differentiation,” in which case, instead of turning into dopamine-producing neurons, cells turn into other types of neurons in different parts of the brain. This can potentially lead to complications after transplantation, such as uncontrolled growth, tumor formation, or impaired nerve function; hence the absolute necessity for accurate identification and isolation of cells that are properly differentiated and have the characteristics of healthy dopamine-producing neurons.
The role of genes in this process is critical; when cells are set on a path to differentiate into a specific function, a set of related genes is activated in them. Known as “gene expression,” this process leads to the production of proteins that determine the function of the cell.
In Parkinson's-related research, the LMX1A gene has been identified as one of the key markers of dopamine-producing neurons, and the expression of this gene in stem cells indicates their successful differentiation into desirable dopamine-producing neurons.
Baharvand's research group has used an innovative method to identify cells that have activated the LMX1A gene. In this method, the gene of a green fluorescent protein was added to the LMX1A gene sequence. As a result, cells expressing the LMX1A gene became visible with a green glow. This sight is very exciting for biologists to see, just as it is enjoyable for astronomers to observe bright stars in the night sky.
These identified cells were then evaluated to confirm their identity and characteristics. The results of their study showed that these cells fully match the characteristics of the dopamine-producing neurons in question. This is a notable step towards the development of stem cell-based treatments for Parkinson's disease.
Given the goal of this research to realize cell therapy for Parkinson's, the studies were not limited to identifying the desired cells. With more detailed analyses, the researchers also examined the molecular differences between these cells and other undifferentiated cells.
A significant finding of this study was the identification of the CNTN2 molecule on the membrane surface of dopamine-producing cells; a molecule that, as a surface marker, allows for more precise isolation and purification of these cells.
Next, cells containing CNTN2 were injected into the brains of animal models of Parkinson's, namely rats whose dopamine-producing neurons had been damaged. The results of these experiments showed that dopamine levels in the brains of these animals increased significantly and their motor symptoms improved remarkably.
There are many complex diseases for which a definitive treatment is still unknown. Researchers, doctors, and biologists are trying to gain a deeper grasp of these diseases and develop new treatments, taking small but effective steps.
Although a certain treatment for Parkinson's is not yet available, every scientific breakthrough in this direction creates new hope and can lead to a brighter future for patients. Hopefully, a day will come when the treatment of Parkinson's disease is not a medical challenge, but rather a prominent example of human scientific achievement in the history of medicine.