19/02/2008
The cause of effectiveness has been discovered for a cirrhosis treatment that has been shown to be useful in 40% of patientsThe Journal of Clinical Investigation has published an article derived from a study undertaken on animals and cellular cultures at the CIMA
Scientists of the Center for Applied Medical Research (CIMA) of the
University of Navarra have discovered the molecular mechanism
responsible for the effectiveness of an existing treatment for primary
biliary cirrhosis, which combines two substances in order to produce an
effect that does not result from either substance separately. The
discovery involved the role played by the AE2 protein when the patient
is treated with a combination of ursodeoxycholic acid (UDCA) together
with glucocorticoids. The research results were recently published in
The Journal of Clinical Investigation.
The
origin of primary biliary cirrhosis (PBC)-which mostly affects
middle-aged women-is still not understood. This pathology is associated
with autoimmune phenomena, damage to the biliary vessels of the liver,
and a reduction in the production of bile.
The possibility of more cures with fewer transplantsIn
Spain more than 1,000 cases are diagnosed each year, and the total
number of patients worldwide is greater than 15,000. Dr. Juan Francisco
Medina, Director of the Laboratory of Molecular Genetics of the CIMA,
explains that in the present day “the diagnosis of this disease, which
is generally detected early, permits treatment with UDCA, which is
effective in over half of the patients. However, nearly 40% of PBC
patients do not respond satisfactorily to monotherapy with UDCA.
Therefore, we looked for a combined treatment, and discovered that the
combination of UDCA with glucocorticoids was a promising treatment for
this group of patients. Those who suffer from this type of cirrhosis
have a deficit of AE2, which is the protein for the secretion of
bicarbonate in the bile.”
The originality of this
recently-published research article consists in relating, for the first
time, the combined treatment with UDCA and glucocorticoids with a
greater quantity of bicarbonate in the bile, and an improvement of the
production of bile by the liver. Specifically, experiments in animal
models and cell cultures demonstrate that “only the combined treatment
with UDCA and glucocorticoids increases the genetic expression of the
human protein AE2 in the liver.”
Based on available data, Dr.
Medina considers that it is advisable to use combined treatment in
those cases which present a poor response to monotherapy with UDCA. He
proposes the use of a corticoid such as budesonida, which has fewer
side effects than cortisone and prednisone: “If, for fear of side
effects, we allow the disease to progress, it is very probable that the
only treatment will be a transplant. On the other hand, if this
treatment option is confirmed as successful, it could reduce the number
of transplants required in order to save the lives of patients.”
The article, published in
The Journal of Clinical Investigation,
is the work of the team at the CIMA of the University of Navarra
directed by Dr. Medina; the other members of the team are Fabián
Arenas, Isabel Hervías, Miriam úriz, Ruth Joplin and Jesús Prieto.