Experts seek to disrupt an acid-sensitive protein

Apr 29, 2009 22:01 GMT  ·  By
Mental health experts and geneticists could soon find a new way of inhibiting depression even before symptoms appear
   Mental health experts and geneticists could soon find a new way of inhibiting depression even before symptoms appear

Depression is a mental condition that has become increasingly widespread over the last couple of decades, and, ever since, has entered the focus of a great number of scientific studies, all aimed at finding cures for it. A host of treatments already exists, but they are unable to cover all aspects of the disease, and are also unsuited for some patients, who cannot tolerate their aftereffects or who are allergic to some of their components. Now, experts at the University of Iowa say that they may have found a new target for depression treatments, in the form of the acid-sensitive ion channel-1a (ASIC1a).

During their study on unsuspecting mice, the researchers learned that suppressing this acid-sensitive protein generated strong anti-depressive effects in the animals, and concluded that a similar approach could be devised for humans as well. One day, this new type of approach could help those who are currently unable to take any form of existing medication to make at least a partial recovery, if not a full one. However, the new therapy is still in its early experimental stages, and it may be some time before it becomes available to the general public.

“Depression is one of the most devastating and difficult-to-treat disorders known to man. Despite much research, all antidepressant medications that are currently prescribed work in much the same way and are of limited efficacy in more than a third of all patients. The development of antidepressants that act on other molecular targets in the brain would be a major breakthrough,” University College Cork in Ireland expert John F. Cryan, PhD, who has not been directly involved with the new study, argued. Details of the finds appear in the April 29th issue of The Journal of Neuroscience.

The UI research team, which has been led by experts Matthew Coryell, PhD, and senior researcher John Wemmie, MD, PhD, learned that treating a mouse with an ASIC1a inhibitor drastically reduced the animal's level of depression. In order to double-check the role of this protein for the model's mood, the researchers also engineered a mouse that lacked the gene expressing the protein altogether. Compared results between the two animals were nearly identical, which again confirmed their hypotheses.

“ASIC1a inhibitors may combat depression by reducing amygdala activity. Because of the importance of the amygdala in negative emotions and fear, we speculate that ASIC1a inhibition increases the brain's resistance to the negative effects of stress, perhaps reducing the likelihood of developing depression,” Wemmie, who has been the author of the new paper, concluded.