- Parkinson's disease (PD) is neuro
degenerative disorder which leads to movement associated problems.
- Slow movement is a common side
effect to currently available PD drugs including agonists.
- New drug compound, D-512, shows
higher efficiency in treatment of early stage PD when compared to
regularly administered ropinirole.
A new drug compound, D-512, may
be able to limit the progression of Parkinson's and also relieve its symptoms
when compared to the other currently available drugs. Researchers at Binghamton
University have done a comparative study on rats to evaluate the efficacy of
ropinirole and D-512 in the management of PD symptoms. The study was published
in The British Journal of Pharmacology.
Parkinson's Disease and its
Parkinson's disease (PD)
is caused due to the
depletion of neurons in the part of the brain called the substantia nigra. This
part of the brain is associated with control of movement. When the neurons here
die, so is the chemical they produce, called dopamine. Loss of dopamine leads
to loss of movement.
‘Clinical trials in mice reveals that drug compound D-512 may limit progression and relieve symptoms of PD.’
involves the progressive loss of dopamine neurons in the substantia nigra,
leading to motor symptoms including:
(Lack Of Movement) Or Bradykinesia (Slow Movement),
is not one known definite cause for PD, and therefore the disease may not be
cured, however, the symptoms can be managed. The commonly used drugs called anti-parkinsonian
drugs are used to treat PD like symptoms.
cannot cross the blood-brain barrier, and hence externally providing dopamine
as a treatment is not possible. However, precursors to dopamine are used as
drugs which change into dopamine in the brain. Another group of frequently
administered drugs are dopamine agonists that mimic dopamine effects in the
brain. Dopamine agonists include pramipexole (Mirapex),
ropinirole (Requip), among others.
These drugs have a wide range of
side effects including hallucinations
and behavioral problems. With
long term usage of these drugs, bradykinesia or slow movement is observed in PD
The New Candidate Drug:
To study the anti-parkinsonian properties of the clinically employed
ropinirole and the novel D-512, the research team, parkinsonism was simulated
in mice and the efficiency of both drug compounds in treating the same were
studied. The ability of each drug to stimulate spontaneous motor activity and
reverse parkinsonian akinesia was studied.
Highlights of The New Drug
- High affinity D2/3 receptor
agonist and therefore able to attach and mimic effects of dopamine
- Has antioxidant and
- May have fewer side effects than
the currently used medications.
- Has longer duration of action than
ropinirole, although both provoked impaired movements. Anti-parkinsonian
effects of ropinirole subsided in 2 hours, but that of D-512 lasted for at
least 4 hours.
- D-512 was able to reverse forelimb
akinesia (lack of movement)
- Rotational behavior, a marker of
anti-PD efficacy was greater for D-512 than ropinirole.
- Blood plasma and brain uptake of
D-512 was greater than ropinirole.
issue for Parkinson's disease patients is the need to take multiple
medications, multiple times per day. So we were quite astounded to discover
that our new compound, D-512, was superior to the widely-used drug, ropinirole,
in terms of maximal symptom relief and duration of action," said
Lidenbach, first author of the study.
- Lindenbach, D., Das, B., Conti, M. M., Meadows, S. M., Dutta, A. K., & Bishop, C. (2017). D-512, a novel dopamine D2 / D3 receptor agonist, demonstrates superior anti-parkinsonian efficacy over ropinirole in parkinsonian rats. British Journal of Pharmacology. doi:10.1111/bph.13937
- New drug may treat and limit progression of Parkinson's disease - (https://www.eurekalert.org/pub_releases/2017-07/bu-ndm073117.php)
- Parkinson's disease - (http://www.mayoclinic.org/diseases-conditions/parkinsons-disease/basics/treatment/con-20028488)