title: Frontal lobe bioenergetic metabolism in depressed adolescents with bipolar disorder: a phosphorus-31 magnetic resonance spectroscopy study.
abstract: OBJECTIVE
  To compare the concentrations of high-energy phosphorus metabolites associated with mitochondrial function in the frontal lobe of depressed adolescents with bipolar disorder (BD) and healthy controls (HC).
  
  
  METHODS
  We used in vivo phosphorus-31 magnetic resonance spectroscopy ((31) P-MRS) at 3 Tesla to measure phosphocreatine (PCr), beta-nucleoside triphosphate (β-NTP), inorganic phosphate (Pi), and other neurometabolites in the frontal lobe of eight unmedicated and six medicated adolescents with bipolar depression and 24 adolescent HCs.
  
  
  RESULTS
  Analysis of covariance, including age as a covariate, revealed differences in PCr (p=0.037), Pi (p=0.017), and PCr/Pi (p=0.002) between participant groups. Percentage neurochemical differences were calculated with respect to mean metabolite concentrations in the HC group. Post-hoc Tukey-Kramer analysis showed that unmedicated BD participants had decreased Pi compared with both HC (17%; p=0.038) and medicated BD (24%; p=0.022). The unmedicated BD group had increased PCr compared with medicated BD (11%; p=0.032). The PCr/Pi ratio was increased in unmedicated BD compared with HC (24%; p=0.013) and with medicated BD (39%; p=0.002). No differences in β-NTP or pH were observed.
  
  
  CONCLUSIONS
  Our results support the view that frontal lobe mitochondrial function is altered in adolescent BD and may have implications for the use of Pi as a biomarker. These findings join volumetric studies of the amygdala, and proton MRS studies of n-acetyl aspartate in pointing to potential differences in neurobiology between pediatric and adult BD.
authors: The Brain Institute, University of Utah, 383 Colorow Drive, Salt Lake City, UT 84108, USA. xianfeng.shi@hsc.utah.edu
authors: Xian-Feng
authors: XF
authors: Shi
authors: Douglas G
authors: DG
authors: Kondo
authors: Young-Hoon
authors: YH
authors: Sung
authors: Tracy L
authors: TL
authors: Hellem
authors: Kristen K
authors: KK
authors: Fiedler
authors: Eun-Kee
authors: EK
authors: Jeong
authors: Rebekah S
authors: RS
authors: Huber
authors: Perry F
authors: PF
authors: Renshaw
mesh_terms: D000293:Adolescent; D001714:Bipolar Disorder / Q000150:complications / Q000378:metabolism* / Q000503:physiopathology; D016022:Case-Control Studies; D003863:Depression / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D004734:Energy Metabolism; D005260:Female; D005625:Frontal Lobe / Q000378:metabolism* / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism; D010725:Phosphocreatine / Q000378:metabolism; D010759:Phosphorus Isotopes; D011122:Polyphosphates / Q000378:metabolism
chemical_list: D010710:Phosphates; D010759:Phosphorus Isotopes; D011122:Polyphosphates; D010725:Phosphocreatine