We begin to understand neurological diseases i

The brain, the unknown, is the new frontier of biomedical research. Thanks to the progress of genetics and medical imaging, hopefully significant advances in the knowledge of this body if different of the other. The central nervous system diseases represent a weight in the modern world, both because of the number of persons concerned and the cost of their support. All combined diseases, migraine to through depression and Alzheimer's disease, multiple sclerosis they receive at any time any of their life for the tens of millions of people in Europe. "This development is explained by the improvement of diagnostic methods, increased awareness of patients and doctors and the ageing of the population," says Françoise Duveau, Director of the Medical Department of the Japanese laboratory Esaï in France. The depression, she alone is lifetime 150 million people, schizophrenia 25 million, and the problems of addiction to alcohol or drugs 90 million, according to a study on the mental health of Europeans conducted under the auspices of the European Commission. The cost of the support of these diseases was in 2000, from 3 to 4 of gross national product of Member States of the European Union.

Arsenal limited

However, with the growing place that occupy these diseases, medicine still has an arsenal limited. We begin to understand neurological diseases, i.e. those for which a biological substrate has been identified, such as Alzheimer's disease, Parkinson's and Huntington's, multiple sclerosis, epilepsy. However, with the exception of Parkinson's disease, is virtually unable to treat. Conversely, almost nothing is known, biologically, of psychiatric diseases (depression, schizophrenia, obsessive compulsive disorder), but there is some effective therapeutic products.

The interest in Psychiatry, of these molecules (often from other therapeutic areas) was discovered incidentally by clinicians in the 1950s. Since the identification of neuroleptic power of chlorpromazine, potential antidepressant of the imiprazine and then a little later, benzodiazepines sulfurous qualities, almost no new high class product saw the day outside the so-called Serotonergic Antidepressants type Prozac.

The growing "biologize" of Psychiatry especially allowed so far to identify the mechanisms of action of these products at the molecular level, but did little to advance the understanding of these diseases. "Laschizophrénie, only a clinical diagnosis is now possible, insists François Menard, psychiatrist attached to the hospital group Cochin.". Even if some anomalies such as atrophy of the cortex may be present, no anatomical or biological substrate specific has yet been identified.

Scientific locks

How explain that, faced with an important and proven medical need and a solvent market, the pharmaceutical industry does itself no more innovative It is yet not without focus. Most of the major groups are included the central nervous system among their priorities, but its characteristics make it difficult to understand by methodologies validated in pharmaceutical research.

To function effectively, this research needs to rely on a foundation of basic knowledge in molecular biology, him missing for the moment largely with respect to the brain. Some groups such as Novartis did not then hesitate to invest very upstream to jump "scientific locks." For example, in working on the genetic factors involved in Alzheimer's disease, in an attempt to renew the approaches. Or through several joint research programmes with academics to better understand the functioning of the amygdala, a brain region that is thought involved in anxiety and depression.

Pharmaceutical research is need also tools, methodologies and objective parameters to measure, quantify. However, diseases of the brain, in particular psychiatric diseases, are restive. "Animal models of these diseases based on analogies on similarities, explains François Ménard.". Only tested on human of new molecules to test their effectiveness. And yet is difficult. Measure a clinical difference between two treatment modalities imposes the use of a large number of patients. "Apply objective criteria to measure results subjective the patient feels better is not completely satisfactory either. And the effect of placebo, again more than elsewhere, plays in full.

New tools

Some pharmaceutical companies like GSK yet spend a lot of energy to develop new conceptual and technical tools. "We are investing heavily in basic research, particularly in the identification of genes associated with diseases such as Alzheimer's, depression, schizophrenia or multiple sclerosis, said Jackie Hunter, Director of the centre for research of GSK in the central nervous system." Our main objective being to establish biomarkers. "GSK also comes to invest 46 million pounds (on a total of 76) in the creation, with the Imperial College, Centre for Clinical Imaging at Hammersmith Hospital campus. It will enable him to follow the marked molecules and compare the effect of the treatment.

But pharmaceutical research is also facing the evolution in time of the contours of psychiatric diseases, because the border between the normal and the pathological is primarily the result of a social consensus, relayed by the experts. Hysteria, celebrated by the 19th century, and disappeared in favour of the depression. As the "DSM" ("Diagnostic and Statistical Manual of mental disorders"), global reference tool for the classification of developed mental disorders developed by the American Psychiatric Association, is in its fourth version.

In fact, paradoxically, "the clinic ahead the Pharmacology and physiology of decades", explains Philippe Pignarre in his book, "these drugs funny." Indeed, real therapeutic progress of recent years much more must the empirical approach of clinicians who try the existing molecules in new indications, based on their understanding patients, to the placing on the market of truly new molecules. The doctor, by reinventing the use of a drug for a particular patient, comes to the individualization of treatment that the pharmaceutical industry is also, but genetic and non-subjective Foundation.

Pills and floor

However, it seems that in Psychiatry, subjectivity as recognition of the subject individual must remain an essential data. "It has been shown that patients combining medication and psychotherapy are less relapse that those who simply only antidepressants, observes Jean-Pol Tassin, Director of research at Inserm, in the France College." Antidepressants allow neurons to overcome their exhaustion, but the floor also has a power, because it is in the relationship to the other that the neuronal connections can reorganize and the patient heal.

Yet, it is depression that progress will be probably the longest to occur because antidepressants to treat a majority of patients, there is still no specific biomarkers of the disease and its biological causes remain hypothetical. The discovery of significant genetic in autism and schizophrenia weight on the other hand offers more encouraging prospects for the industry. Even if the understanding of a disease does not necessarily imply that can cure, as shown in the example of the Huntington's disease, we know that it is purely genetic in origin but is not treat.