TITLE:
Increased myo-inositol in the posterior cingulate cortex in first-episode major depressive patients
AUTHORS:
Lily Magally Granados-Domínguez, Enrique O. Flores-Gutiérrez, Sarael Alcauter, Juan José Cervantes, Marina Torres-Álvarez, María Corsi-Cabrera
KEYWORDS:
Major Depressive Disorder; Posterior Cingulate Cortex; Metabolites; 1H-MRS; Myo-Inositol; N-Acetyl-Aspartate
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.4 No.6A,
June
20,
2013
ABSTRACT: Major
depressive disorder (MDD) is a severe, disabling pathology characterized, in addition
to affective, cognitive and motor symptoms, by self-focused attention and
rumination. During recursive self-focused processes and rumination, the
posterior cingulate cortex (PCC) is activated. In vivo proton magnetic resonance spectroscopy (MRS) is a
noninvasive imaging technique that can directly assess living biochemistry in
localized brain regions. The aim of this study, therefore, was to use 1H-MRS
as a means of analyzing brain metabolites in the PCC of a group of
first-episode, unmedicated MDD patients. PCC metabolite levels were analyzed
at 3-T in a single voxel located bilaterally over the PCC in 7 patients diagnosed
for the first time with MDD and with no previous pharmacological treatment,
as well as in 9 control subjects. Differences in metabolite levels between
groups were compared using independent t-tests. Myo-inositol was significantly
higher, and NAA + NAAG/Cr significantly lower, in MDD patients than in
controls. The other brain metabolites showed no statistical differences. The
present results suggest that alterations in PCC metabolite levels are likely involved in MDD pathophysiology, and may help to improve our understanding of MDD
and the role of the PCC in some symptoms of depression.