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Parkinsons disease (PD) is a progressive brain disorder that impacts the nervous system. It is caused by damaging nerve cells in the segment of the brain called the substantia nigra. These cells are responsible for producing a chemical, dopamine that transmits messages between the brain and the nerves regulating body movements. People often experience tremors, impaired balance, muscle stiffness and slowness of movement.
Parkinsons is an age-related degenerative disorder mostly impacting men of 60 years age and above. However, it can be rarely observed in adults as young as 20 years of age when they have a parent or sibling having an identical condition. Parkinsons disease cannot be healed completely, yet medicines, surgical treatments and further therapies can alleviate some symptoms.
Drugs for Parkinsons disease are used primarily to treat it. Medication for Parkinsons disease often increases dopamine levels in the brain, thus affecting neurotransmitters and regulating non-movement symptoms. Surgery is a secondary treatment option. A device is implanted that delivers mild electric current to parts of the brain stimulating its functioning.
Advanced Treatments for Parkinsons Disease
Some of the latest Parkinsons disease treatment procedures are discussed in this section.
Deep brain stimulation
This surgical procedure is offered to people having advanced Parkinsons disease and erratic medication responses. In deep brain stimulation(DBS), electrodes are implanted into specific brain parts by surgeons. These are further connected to a generator that is implanted in patients’ chests that transmits electric pulses to the brain reducing disease symptoms. This surgery may involve some risks of infections, brain haemorrhage or strokes.
Parkinsons disease cure is often achieved by gene-targeted treatments.
Glutamic acid decarboxylase (GAD) — The enzyme can increase the formation of a brain chemical, gamma-aminobutyric acid (GABA). A GAD gene was introduced in the subthalamic nucleus in the brains of Parkinsons patients. This results in higher GABA production in that area thus normalising the abnormal circuitry of the patient’s brain.
Aromatic amino acid decarboxylase (AADC ) — This enzyme catalyses the conversion of Levodopa (drug) to dopamine. A gene encoding AADC is introduced into the putamen in the brains of PD patients. This can make Levodopa treatment more effective by enhancing the amount of AADC present.
These neuron-repair therapies help in repairing the damaged neurons and enable new neuron formation. Neuroprotection indicates any intervention that may lead to interruption or prevention of death of dopamine-generating cells thus halting disease progression.
Biomarkers are biological molecules that are found in body fluids, blood and tissues and indicate a condition or disease in an individual. It can be employed to observe the response of a body to treatment for a disease. PD biomarkers are classified into four main types: imaging, clinical, genetic and biochemical. The most promising biomarkers used for detection are amino acids, protein biomarkers, dopamine metabolites etc in serum, blood and cerebrospinal fluid.
Some promising clinical biomarkers for detecting prodromal PD include rapid eye movement sleep behaviour disorder, constipation, hyposmia and mood disorders.
Neural transplantation in the context of neurodegenerative diseases like Parkinsons disease refers to the replacement of cells that are lost or damaged during the disease progression. Currently, the primary fetal ventral mesencephalon (VM) which marks the basis of bona fide midbrain dopaminergic precursors is considered the gold standard resource of cells for transplantation.
Drugs for Treating Parkinsons Disease
Medication for Parkinsons disease is given below.
Levodopa is the most important drug for Parkinsons disease. It is a natural chemical that passes onto the brain and is used by nerve cells to produce dopamine. It is usually taken with another medicine for Parkinsons, Carbidopa which prevents early conversion to dopamine outside the brain. Carbidopa also reduces the side effects of levodopa therapy like vomiting, low blood pressure and restlessness. It is recommended not to stop taking levodopa without a doctor’s consent.
Parkinsons disease cure can also be achieved by therapeutic approaches that transform the brain’s immune microenvironment. This includes interventions that immunologically refurbish the brain’s homeostasis, giving rise to neuroprotective solutions. One of the approaches includes increasing the numbers and function of regulatory T cells over dominant effector cells that impair neurodegeneration. These therapeutics help in overcoming not only PD but also Alzheimer's disease, traumatic brain injuries and stroke.
Repurposing drugs can be employed at different stages of drug development, although it is more favourable when the drug safety is tested previously. Some disease-modifying pharmacotherapies like nilotinib, isradipine and inosine are repurposed to treat PD. Some other (Food and Drug Administration) FDA- approved PD drugs are Ropinirole, Amantadine and Rasagiline.
Drugs Affecting Other Neurotransmitters
Drug addiction and dependence can be caused due to the cumulative impact of drugs on neurotransmission. Some drugs like methamphetamine, nicotine, heroin and painkillers are impacting different neurotransmitters like acetylcholine, GABA, histamine and serotonin. This can alter a person’s behaviour by impeding normal communication between brain cells.
1) How long can a patient live with Parkinsons disease?
An individual suffering from Parkinsons disease experiences a shorter life span at times than a healthy individual of a similar age group. The disease makes people vulnerable to life-threatening infections as studied. However, with recent advanced medical techniques, most people have a standard or near-normal life expectancy.
2) Which age usually marks the beginning of Parkinsons?
Parkinsons disease is a neurodegenerative disorder which usually starts post 60 years in individuals. However, 5-10% population may experience early onset of symptoms which may or may not be inherited.
3) Can Parkinsons disease be genetically transmitted?
Research shows that several genetic factors may increase the potential risk of developing Parkinsons disease. It may be due to gene mutations which are inherited from the parents to the children although the exact reason is unknown. Scientists say that a combination of genetic and environmental factors may induce Parkinsons disease in individuals.