31P-MRS study of acetyl-L-carnitine treatment in geriatric depression:: preliminary results

Objective: This 12-week study of two elderly, depressed Subjects investigated the effect of acetyl-L-carnitine (ALCAR) treatment on the Hamilton Depression Rating Scale (HDRS) and on measures of high-energy phosphate and membrane phospholipid metabolism. Methods: Two mildly depressed (HDRS 15-20). non-demented male subjects 70 and 80 years old were compared with six non-demented controls (all males, mean age of 73.6 +/- 3.6 years). High-energy and membrane phospholipid metabolites were measured by phosphorus magnetic resonance spectroscopic Imaging (P-31 MRSI) analysis. HDRS and P-31 MRSI measurements were taken Lit entry, 6 and 12 weeks for the depressed subjects. Results: P-31 MRSI analysis revealed elevated levels of phosphomonesters [PME(s - tau(c))] in the prefrontal region of these mildly depressed subjects, which decreased with ALCAR treatment and showed a trend for correlation of the PME(s - tau(c)) levels with HDRS. ALCAR treatment also resulted in increasing levels of the prefrontal phosphocreatine (PCr). which correlated with HDRS. Conclusions: In the prefrontal region. the mildly depressed subjects compared with controls had elevated PME(s - tau(c)) levels which normalized after 12 weeks of ALCAR and increased PCr levels after ALCAR treatment. These preliminary findings suggest further studies are warranted.