In the field of neuroscience, there have been startling discoveries that have transformed the understanding of the brain and helped to deliver treatment for disorders affecting millions. Serdia has been extensively involved in research on the Central Nervous System. Currently, in this field, we have an antiparkinsonian agent and an antidepressant.

Parkinson’s disease initially described in 1817 by James Parkinson, has always provided clinicians with a therapeutic challenge. Since 1960, the dopaminergic rationale and the unquestionable therapeutic value of levodopa in the treatment of Parkinson’s disease have been very well documented. Nevertheless, both the motor complications induced by levodopa, and the occurrence of non-dopa-sensitive symptoms have recently aroused the interest of many experts on new research and development in Parkinson’s disease.

Dopamine agonists, a class of drugs that share the capacity to directly stimulate the dopaminergic receptors have been introsduced in clinical practice. There has been considerable interest in this class of drugs because of their potential to provide antiparkinson’s effect without some of the problems associated with levodopa. However, recent findings show that the pathophysiology of Parkinson’s disease is not related only to the decline in dopaminergic function. Indeed, during disease evolution, a progressive decline of noradrenergic tracts, especially in the locus coeruleus takes place. This leads to the occurrence of certain symptoms like posture and gait disorders, cognitive dysfunction, dysautonomia, and depressive episodes that remain resistant to levodopa treatment.

Numerous clinical and pre-clinical studies have implicated noradrenaline as the most important neurotransmitter causing these non-levodopa-sensitive symptoms in Parkinson’s disease. In fact, by use of therapeutic agents like synthetic noradrenaline precursors, 2-adrenoceptor antagonists, the benefits of restoring central noradrenaline levels back to normal have been shown. In such a situation, dopamine agonists with additional noradrenergic properties appear to be ideal drugs.

Depression is one of the most common disorders of modern society. The World Health Report 2001 highlighted that depression is the 4th leading cause of burden among the various diseases. Not only does depression have devastating effects on the affected individual, but it also has a significant impact on the family. Today the incidence of depression is more than 10% and with the changing lifestyle, the incidence is bound to increase.

Until recently, one of the most widely accepted theories of the neurochemical basis for depression involved deficits in CNS neurotransmitter systems such as serotonin and noradrenaline. Most antidepressants increase the amount of neurotransmitters in the synaptic cleft. However there is a growing body of evidence that synaptic serotonin or noradrenaline level deficiency may not actually explain the clinical outcome of antidepressant activity. On the contrary an antidepressant like tianeptine, which increases the serotonin reuptake has been found to be useful clinically. There is also a link between the antidepressant activity and suppression of the HPA axis. Thus new insights in the pathophysiology of depression have led to the discovery of safe and effective antidepressants with a novel mechanism of action.