New therapeutic targets for neurodegenerative diseases

Researchers at the University of the Basque Country (UPV-EHU) are studying the signals in the central nervous system – the brain and the spinal cord – that do not function well, in particular, those signals that cause the death of nerve cells. There are basically two types of cells in the central nervous system: neurones and the glial cells. Both types are sensitive to these functioning errors and both can die. In the case of Alzheimer’s disease, it is the neurones, above all, that die. However, in the case of multiple sclerosis, it is a class of glial cells – known as oligodendrocytes – that perish.

From in vitro cells to biological samples of human origin

The researchers at the Neurobiology Laboratory are investigating cells in cultures – neurones, oligodendrocytes or other cells of the nervous system -, and are trying to reproduce in vitro circumstances that are thought to be relevant in these ailments. That is to say, they are creating the conditions that cause the death of these cells, in order to determine what molecules intervene in the process – from the moment of the lethal signal to the point where the cells collapse. In this type of experimental work a series of molecules involved in the death process are identified, the aim being to come up with pharmaceutical medicines that will improve treatment.

Apart from working with in vitro cells, they are also experimenting with animals that reproduce some of the elements involved in neurodegenerative illnesses under certain conditions, i.e. sensory symptoms, motor symptoms, etc. and that can be induced in these animals. And they are examining if these substances that have proved to be interesting with the in vitro cells are also efficacious in these experimental models of the diseases.

Moreover, over the past few years they have had the opportunity to study samples of brains of patients who have died of some neurodegenerative illness, such as, for example, multiple sclerosis. The illnesses leaves a mark in these samples and, although the brain has been at a terminal stage of the illness, they can investigate to see if there are signs of alterations to the molecules similar to those observed in the experiments, both with cells and with the animals. In this way it can be determined if the molecular targets discovered experimentally are relevant or not to the neurodegenerative processes and, if they are, develop pharmaceutical medicines that can neutralise these processes or the elements that enable them to progress, the goal being to halt the process of death.

In collaboration with neurologists they have also been able to access biological samples of patients who have given their consent and donated them to research. Biological samples such as, fundamentally, blood, given that changes in blood plasma that may indicate alterations at the brain level can be identified.

In search of biological samples

All this is a dynamic process that enables clues to be found and which are, in some cases, relevant for developing pharmaceutical drugs that can halt, or at least slow down, the course of a neurodegenerative illness. Apart from finding these molecules or targets that interact with pharmaceutical medicines, in order to stop the process of progressive deterioration, substances that favour the survival of the neurones and oligodendrocytes are also sought; substances such as, for example, antioxidants, given that, in many of the neurodegenerative illnesses the cells die because oxidative stress is produced. In recent years the Neurobiology Laboratory researchers have found a number of antioxidants that put a brake on the dying process and can act as a neuroprotector. Antioxidants of natural origin that are in our diet – fruit, vegetables, and so on – and which, in some way appear to alleviate the damage cause by these illnesses.

In short, the goal is to gain more knowledge about the molecular bases of these pathologies, define therapeutic targets (molecules of the cell that recognise a pharmaceutical drug and thus respond to it) and, in the last analysis, to come up with pharmaceutical medicines that improve treatment.