Parkinson's disease is known as a chronic neurodegenerative disorder that affects the nerve cells producing dopamine, the chemical responsible for transmitting signals between regions in the brain. Dopamine is also responsible for the smooth and coordinated movements of the body. When dopamine levels begin to decrease, it impacts body movements. While there is no cure for Parkinson's disease, there are symptomatic treatments, including medications, regular physical exercises, and natural therapies focusing on balance and stretching, among others.
**Genetically Modified Bacteria**
However, new research presented at the Annual Meeting of the American Society for Pharmacology and Experimental Therapeutics in Philadelphia may provide hope for patients, having shown that genetically modified bacteria may be an effective treatment for Parkinson's. Researchers have developed bacteria that can produce a steady source of medication within the patient's intestines, and tests conducted on animals have proven to be safe and effective, according to New Atlas.
The idea of engineering bacteria to serve as medical treatments is not new. Scientists have experimented for many years with ways to modify bacteria to meet individuals' needs, from engineering bacteria to consume excess ammonia in the human body to helping bacteria track colorectal cancer cells.
**Different Challenges**
However, of course, before such ideas become ready for mainstream clinical use, several obstacles must be overcome. Providing controlled doses of medication to patients in the form of pills, syrups, or injections is well-known. However, limiting the growth of live genetically engineered microbes to produce those therapeutic molecules within the human gut presents a completely different challenge.
**A Gradual Step Forward**
The new research is a gradual step forward in engineering a new strain of human microbiota, E.coli Nissle 1917, developed to continuously manufacture and secrete the Parkinson's disease drug known as L-DOPA in the patient's gastrointestinal tract.
L-DOPA is a molecule that acts as a precursor to dopamine and has been a successful treatment for Parkinson's patients for decades. However, doctors have discovered that after about five years of receiving this medication, patients often experience side effects known as dyskinesia. These side effects are believed to be linked to the lack of a continuous source of medication supply to the brain.
Therefore, to address this issue, the new research explored whether bacteria producing L-DOPA in the gut could lead to a steady delivery of the drug to the brain.
**Therapeutically Effective Amounts**
Biyush Badi, a co-researcher in the study, stated that the engineered bacteria consume a molecule called tyrosine and secrete L-DOPA in the patient's gastrointestinal tract. Furthermore, several experiments on mice have shown that the genetically engineered bacteria resulted in stable and consistent concentrations of L-DOPA in the blood. Subsequent experiments conducted on animal models with Parkinson's disease found that the treatment improved motor and cognitive functions, suggesting that the engineered bacteria were producing therapeutically effective amounts of the drug.
The researchers also claim that the levels of L-DOPA produced by the bacteria can be precisely controlled, either by limiting the daily doses of bacteria consumed in capsules or by adjusting the intake of a sugar called rhamnose, which the bacteria need to continue producing L-DOPA.
Anumantha Kanthasamy, another co-researcher in the study, mentioned that the team of scientists is currently working on adapting the approach to treat other diseases that require continuous medication doses, such as Alzheimer's and depression.
