The effects of therapeutic hypothermia on cerebral metabolism in neonates with hypoxic-ischemic encephalopathy: An in vivo 1H-MR spectroscopy study. Issue 6 (June 2016)

• Record Type: Journal Article
• Authors: Wisnowski, Jessica L; Wu, Tai-Wei; Reitman, Aaron J; McLean, Claire; Friedlich, Philippe; Vanderbilt, Douglas; Ho, Eugenia; Nelson, Marvin D; Panigrahy, Ashok; Blüml, Stefan
• Is Part Of: Journal of cerebral blood flow & metabolism. Volume 36:Issue 6(2016)
• Page Start: 1075
• Page End: 1086
• Publication Date: 2016-06
• Subjects: Energy metabolism -- glutamate -- hypothermia -- neonatal ischemia -- neuroprotection -- neurotransmitters; Cerebral circulation -- Periodicals; Brain -- Metabolism -- Periodicals; Brain -- Blood-vessels -- Periodicals; Cerebrovascular disease -- Periodicals; 612.824
• DOI: 10.1177/0271678X15607881
• Languages: English
• ISSNs: 0271-678X

Abstract

Therapeutic hypothermia has emerged as the first empirically supported therapy for neuroprotection in neonates with hypoxic-ischemic encephalopathy (HIE). We used magnetic resonance spectroscopy ( 1 H-MRS) to characterize the effects of hypothermia on energy metabolites, neurotransmitters, and antioxidants. Thirty-one neonates with HIE were studied during hypothermia and after rewarming. Metabolite concentrations (mmol/kg) were determined from the thalamus, basal ganglia, cortical grey matter, and cerebral white matter. In the thalamus, phosphocreatine concentrations were increased by 20% during hypothermia when compared to after rewarming (3.49 ± 0.88 vs. 2.90 ± 0.65, p < 0.001) while free creatine concentrations were reduced to a similar degree (3.00 ± 0.50 vs. 3.74 ± 0.85, p < 0.001). Glutamate (5.33 ± 0.82 vs. 6.32 ± 1.12, p < 0.001), aspartate (3.39 ± 0.66 vs. 3.87 ± 1.19, p < 0.05), and GABA (0.92 ± 0.36 vs. 1.19 ± 0.41, p < 0.05) were also reduced, while taurine (1.39 ± 0.52 vs. 0.79 ± 0.61, p < 0.001) and glutathione (2.23 ± 0.41 vs. 2.09 ± 0.33, p < 0.05) were increased. Similar patterns were observed in other brain regions. These findings support that hypothermia improves energy homeostasis by decreasing the availability of excitatory neurotransmitters, and thereby, cellular energy demand.