Scientists from Nanyang Technological University (NTU) have unlocked a potential treatment for Parkinson's disease in the form of existing anti-malaria drugs.
Along with scientists from McLean Hospital and Harvard Medical School in the United States, they discovered that chloroquine and amodiaquine could activate a protein called Nurr1, which affects the brain's ability to generate dopamine neurons.
When tested on rats with the disease - a degenerative disorder of the central nervous system - the drugs were found to restore the production of dopamine, which improved their behaviour.
The rats later showed no symptoms of the disease.
Dopamine is an important neurotransmitter that affects motor control and movement of muscles in the body. When people are afflicted with Parkinson's disease, their brain's production of dopamine neurons is disrupted, causing them to progressively lose control of their movements.
The condition affects three out of every 1,000 people aged over 50 in Singapore.
There is currently no cure or treatment for Parkinson's disease, which affects an estimated 10 million people worldwide.
Present treatments only address symptoms through the implantation of a medical device to stimulate the brain, using electric currents, or by replenishing their dopamine levels through medication. Side effects of the latter include hallucinations and involuntary movements.
The co-lead scientist, Associate Professor Yoon Ho Sup from NTU's School of Biological Sciences, said: "Once several potential drugs are found, we can redesign them to be effective in combating their targeted diseases while reducing the side effects."
The team now aims to design drugs for Parkinson's by modifying the anti-malaria drugs - a process that could take five years before reaching clinical trials.
Prof Yoon added: "There is still a long way to go but this research gives us hope to design new drugs that can target the proven target."
The research was published in the scientific journal, Proceedings Of The National Academy Of Sciences Of The United States Of America.