Effect of Thyroid Hormones on the Glycolytic Enzyme Activity in Brain Areas of the Rat

Abstract

The glycolytic metabolism through the key enzymes, hexokinase, phosphofructokinase, pyruvate kinase and lactate dehydrogenase, have been studied in the brain areas: anterior cortex, amygdala, hypothalamus, septum and hippocampus in adult rats with pharmacologically induced hyperthyroidism. The oxidative metabolism of glucose is accelerated in most brain areas by treatment with high doses of T(3), as is shown by the increase in HK activity, approaching normality on reducing the dose. This decrease can also by observed in the PFK activity through the effect of assayed doses of thyroxine. The anterior cortex is the only brain area that does not show significant variations of PK activity through the effects of treatment with thyroid hormones. On the other hand, a general inhibition of the glycolytic anaerobic pathway by treatment with T(3) was observed.

Influence of Thyroid Hormone Deficiency on the Citrate Synthase Activity in Rat Brain Regions during Early Postnatal Development

“…It appears that the dif ferent brain regions not only have their own schedule of maturation, but also a specific susceptibility to thyroid hormone-induced enzyme changes [11]. However, the results obtained in this report show that when hypo thyroidism is induced at birth, citrate syn thase activity uniformly decreases in all brain areas studied, with the exception of the cere bellum, where a transitory rise was observed during the first few days of life.…”

Genome Sequencing of the Perciform Fish Larimichthys crocea Provides Insights into Molecular and Genetic Mechanisms of Stress Adaptation

“…3 ), which is beneficial for saving energy during hypoxia stress. Thyroid hormones can also accelerate the oxidative metabolism of glucose and inhibit the glycolytic anaerobic pathway [ 46 ]. Interestingly, genes involved in the tricarboxylic acid (TCA) cycle (pyruvate dehydrogenase complex [ PDC-E1 ], succinyl-CoA synthetase [ SCS ], and fumarate hydratase [ FH ]) were down-regulated 12 h later under hypoxia, whereas glycolysis-related genes, such as pyruvate kinase ( PKM ), glyceraldehyde 3-phosphate dehydrogenase ( GAPDH ), GPI , and aldolase A ( ALDOA ), were greatly increased at 1 h respectively ( S14 – S15 Fig ).…”

Genome sequencing of the perciform fishLarimichthys croceaprovides insights into stress adaptation

“…3), which is beneficial for saving energy during hypoxia stress. Thyroid hormones can also accelerate the oxidative metabolism of glucose and inhibit the glycolytic anaerobic pathway (Sabell et al 1985). Our transcriptome analyses show that genes involved in the tricarboxylic acid (TCA) cycle (pyruvate dehydrogenase complex [ PDC-E1 ], succinyl-CoA synthetase [ SCS ], and fumarate hydratase [ FH ]) were down-regulated 12 h later under hypoxia, whereas glycolysis-related genes, such as pyruvate kinase ( PKM ), glyceraldehyde 3-phosphate dehydrogenase ( GAPDH ), GPI , and aldolase A ( ALDOA ), were greatly increased at 1 h (280-, 130-, 73- and 12-fold, respectively) ( Supplemental Table S24 ).…”