David G. Harper1,2, J. Eric Jensen, 2,3,
Caitlin Ravichandran, 2,4, E. Yusuf Sivrioglu5, Daniel
Iosifescu6,7, Perry Renshaw8, Brent Forester, 29
1Geriatric Psychiatry, McLean Hospital,
Belmont, MA, United States; 2Psychiatry, Harvard Medical School,
Belmont, MA, United States; 3Neuroimaging Center, McLean Hospital,
Belmont, MA, United States; 4Laboratory for Psychiatric
Biostatistics, McLean Hospital, Belmont, MA, United States; 5Psychiatry,
Uludag University, Bursa, Turkey; 6Psychiatry, Massachusetts
General Hospital, Boston, MA, United States; 7Psychiatry, Harvard
Medical School, Boston, MA, United States; 8Psychiatry, University
of Utah, Salt Lake City, UT, United States; 9Geriatric Psychiatry,
Mclean Hospital, Belmont, MA, United States
Biological
membranes serve numerous, essential cellular functions. MRI findings in late life depression
include increased white matter hyperintensities and reduced fractional
anisotropy as measured by diffusion tensor imaging suggesting that membrane
integrity, especially in white matter, may be compromised.
Phosphatidylethanolamine, in the inner mitochondrial membrane, serves an
essential function and is synthesized via a unique pathway not involving
phosphoethanolamine. We hypothesized that
glycerophosphocholine (GPCho) and
glycerophosphoethanolamine (GPEtn), particularly in white matter, will be
increased in late-life depression, and we hypothesized that GPEtn will be
altered fundamentally differently than GPCho due to the additional pathway of
the inner mitochondrial membrane and that GPEtn would therefore show changes
in gray matter.