Clinical Application of MR Spectroscopy in Identifying Biochemical Composition of the Intracranial Pathologies

Neumann

et al. 2020

Preprint

In recent years there has been increasing evidence of an inflammatory component due to overstimulation of the hypothalamic-pituitary-adrenals (HPA) in depression. The glutamate metabolites (glutamate and glutamine) are important metabolites that are involved in this stimulation. The aim of this study was to determine the concentrations of hypothalamic glutamate metabolites in depression and to investigate their relationship to peripheral inflammation. Participants with diagnosed depression (DE; n = 24) and control subjects without depression (HC; n = 25) were investigated. Hypothalamic glutamate metabolites were recorded using in vivo magnetic resonance spectroscopy. Peripheral cytokines (IL-6, TNF-α, IFN-γ and IL-1β) were assessed using Enzyme-Linked Immunosorbent Assay. For statistical analysis, generalized mixed models were computed using Poisson distributions and a log link function. The results show overall higher hypothalamic glutamate metabolites in DE compared to HC. High TNF-a and IL-1ß concentrations are associated with high hypothalamic glutamate metabolites in DE. These results provide initial evidence that, in depression, increased HPA axis activity is associated with peripheral inflammation favored by hypothalamic glutamate metabolites.

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

WITHDRAWN: The secret behind peripheral inflammation and depression: The hypothalamus

Pedraz-Petrozzi

Neumann

et al. 2020

Preprint

“…1 H-MRS enables the non-invasive detection of the concentrations of various brain metabolites using strong magnetic elds (25). The concentrations of metabolites or neurotransmitters can be determined using 1 H-MRS (26), including glutamine metabolites such as glutamate (Glu) and glutamine (Gln) (27) or the metabolite Glx, which is the sum of Gln and Glu (28). These glutamate metabolites are mainly associated with central nervous system (CNS) excitatory activity (27,28).…”

Section: Introductionmentioning

confidence: 99%

“…The concentrations of metabolites or neurotransmitters can be determined using 1 H-MRS (26), including glutamine metabolites such as glutamate (Glu) and glutamine (Gln) (27) or the metabolite Glx, which is the sum of Gln and Glu (28). These glutamate metabolites are mainly associated with central nervous system (CNS) excitatory activity (27,28). It is known that glutamic activity in the CNS plays a fundamental role in brain metabolic activity, glucose uptake, and excitatory electrical activity in the CNS (23).…”

Section: Introductionmentioning

confidence: 99%

WITHDRAWN: Hypothalamic Glutamine-Glutamate Metabolites and Peripheral Pro-Inflammatory Cytokines in Participants with Depression: A Case-Control Study

Neumann

et al. 2020

Preprint

Background: In recent years, there has been increasing evidence of an inflammatory component due to overstimulation of the hypothalamic-pituitary-adrenal axis (HPAA) in depression. The glutamate metabolites (glutamate and glutamine) are important in this stimulation. The aim of this study was to determine the concentrations of hypothalamic glutamate metabolites in depression and to investigate their relationship to peripheral inflammation. Methods: Participants with diagnosed depression (DE; n = 24) and control subjects without depression (HC; n = 25) were investigated. Hypothalamic glutamate metabolites were recorded using in vivo magnetic resonance spectroscopy. Peripheral cytokines (IL-6, TNF-α, IFN-γ and IL-1β) were assessed using Enzyme-Linked Immunosorbent Assay. For statistical analysis, generalized mixed models were computed using Poisson distributions and a log link function. Results: The results show overall higher hypothalamic glutamate metabolites in DE compared to HC. High TNF-α and IL-1β concentrations are associated with high hypothalamic glutamate metabolites in DE. Conclusions: These results provide initial evidence that, in depression, increased HPAA activity is associated with peripheral inflammation favored by hypothalamic glutamate metabolites.

“…The rst molecule, Myo Inositol (mIns), is a simple sugar that serves as an intracellular second-messenger 14 . In the central nervous system (CNS), mIns is synthesized in glial cells, predominantly in the astrocytes 15 . The second molecule, Glucose (Glc), is another important molecule in the CNS, which is used as the primary source of energy.…”

Section: Introductionmentioning

confidence: 99%

WITHDRAWN: Hypothalamic Myo-Inositol and Glucose concentrations, mood symptoms and fatigue in depression: a 3 Tesla chemical-shift-imaging in vivo proton magnetic resonance spectroscopy study

Pedraz-Petrozzi

Sammer

2020

Preprint

Background: Many studies have confirmed altered brain Myo-Inositol (mIns) and Glucose (Glc) concentrations in depression. Alterations in the mIns-concentrations may represent a glial dysfunction and are associated mostly with depression symptoms. In comparison, alterations in the Glc-concentrations could represent impaired glucose metabolism. Despite this information, studies that assess these metabolites in the hypothalamus are missing. Therefore, this study aims to investigate mIns- and Glc-concentrations in the hypothalamus of participants with depression concerning mood symptoms and fatigue.Methods: We performed an in vivo proton magnetic resonance spectroscopy – chemical shift imaging of the hypothalamus in 49 participants (25 with depression diagnosis or DE, 24 healthy controls or HC), evaluating mIns- and Glc-concentrations. Concerning information about symptoms, we recollected information on depression symptomatology (BDI-FSTOT) and fatigue (FIS-D). For statistical analysis, we run generalized linear models by using the Poisson regression model with count data.Results: The results showed reduced hypothalamic mIns-concentration for every DE participant with higher FIS-D and higher BDI-FSTOT values (OR = 0.022; p < 0.001; CI95 [0.004 to 0.09]). Besides, the results showed increased hypothalamic Glc-concentration for every participant of the DE group and with higher BDI-FSTOT values (OR = 4.827; p = 0.002; CI95 [1.826 to 13.749]).Conclusions: These results provide initial evidence of a glial dysfunction and impaired glucose metabolism in the hypothalamus associated with mood symptoms and fatigue. Future studies are needed to confirm these pathophysiologic mechanisms.