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Articles by J. C Umhau
Total Records ( 2 ) for J. C Umhau
  J. C Umhau , R Momenan , M. L Schwandt , E Singley , M Lifshitz , L Doty , L. J Adams , V Vengeliene , R Spanagel , Y Zhang , J Shen , D. T George , D Hommer and M. Heilig
 

Context  Acamprosate is approved for the treatment of alcoholism, but its mechanism of action remains unclear. Results of animal studies suggest that a persistent hyperglutamatergic state contributes to the pathogenesis of alcoholism and that acamprosate may exert its actions by intervening in this process. Human translation of these findings is lacking.

Objective  To examine whether acamprosate modulates indices of central glutamate levels in recently abstinent alcohol-dependent patients as measured using proton nuclear magnetic resonance spectroscopy (1H-MRS).

Design  A 4-week, double-blind, placebo-controlled, randomized controlled experimental medicine study, with 1H-MRS measures obtained on days 4 and 25.

Setting  An inpatient research unit at the NIH Clinical Center.

Patients  Thirty-three patients who met the DSM-IV criteria for alcohol dependence and who were admitted for medically supervised withdrawal from ongoing alcohol use.

Intervention  Four weeks of acamprosate (initial oral loading followed by 1998 mg daily) or matched placebo, initiated at the time of admission.

Main Outcome Measures  The glutamate to creatine ratio as determined using single-voxel 1H-MRS in the anterior cingulate. Exploratory neuroendocrine, biochemical, and behavioral outcomes were also collected, as were safety- and tolerability-related measures.

Results  There was a highly significant suppression of the glutamate to creatine ratio across time by acamprosate (time x treatment interaction: F1,29 = 13.5, P < .001). Cerebrospinal fluid levels of glutamate obtained in a subset of patients 4 weeks into abstinence were uncorrelated with the MRS measures and unaffected by treatment but were strongly correlated (R2 = 0.48, P < .001) with alcohol dependence severity. Other exploratory outcomes, including repeated dexamethasone–corticotropin-releasing hormone tests, and psychiatric ratings were unaffected. Among tolerability measures, gastrointestinal symptoms were significantly greater in acamprosate-treated individuals, in agreement with the established profile of acamprosate.

Conclusion  The MRS measures of central glutamate are reduced across time when acamprosate therapy is initiated at the onset of alcohol abstinence.

Trial Registration  clinicaltrials.gov Identifier: NCT00106106

  J. C Umhau , W Zhou , R. E Carson , S. I Rapoport , A Polozova , J Demar , N Hussein , A. K Bhattacharjee , K Ma , G Esposito , S Majchrzak , P Herscovitch , W. C Eckelman , K. A Kurdziel and N. Salem
 

Docosahexaenoic acid (DHA; 22:6n-3) is a critical constituent of the brain, but its metabolism has not been measured in the human brain in vivo. In monkeys, using positron emission tomography (PET), we first showed that intravenously injected [1-11C]DHA mostly entered nonbrain organs, with ~0.5% entering the brain. Then, using PET and intravenous [1-11C]DHA in 14 healthy adult humans, we quantitatively imaged regional rates of incorporation (K*) of DHA. We also imaged regional cerebral blood flow (rCBF) using PET and intravenous [15O]water. Values of K* for DHA were higher in gray than white matter regions and correlated significantly with values of rCBF in 12 of 14 subjects despite evidence that rCBF does not directly influence K*. For the entire human brain, the net DHA incorporation rate Jin, the product of K*, and the unesterified plasma DHA concentration equaled 3.8 ± 1.7 mg/day. This net rate is equivalent to the net rate of DHA consumption by brain and, considering the reported amount of DHA in brain, indicates that the half-life of DHA in the human brain approximates 2.5 years. Thus, PET with [1-11C]DHA can be used to quantify regional and global human brain DHA metabolism in relation to health and disease.

 
 
 
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