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Soya phytoestrogens change cortical and hippocampal expression of BDNF mRNA in male rats
Sandra E File1, David E Hartley, Nazmul Alom
1Psychopharmacology Research Unit and Biochemical Neuropharmacology Group, Centre for Neuroscience Research, King's College London, Hodgkin Building, Guy's Campus, SE1 1UL, London, UK.
Abstract:
Adult male hooded Lister rats were either fed a diet containing 150 microg/g soya phytoestrogens or a soya-free diet for 18 days. This concentration of phytoestrogens should have been sufficient to occupy the oestrogen-beta, but not the oestrogen-alpha, receptors. Using in situ hybridisation, significant reductions were found in brain-derived neurotrophic factor (BDNF) mRNA expression in the CA3 and CA4 region of the hippocampus and in the cerebral cortex in the rats fed the diet containing phytoestrogens, compared with those on the soya-free diet. No changes in glutamic acid decarboxylase-67 or glial fibrillary acidic protein mRNA were found. This suggests a role for oestrogen-beta receptors in regulating BDNF mRNA expression.
Insights
Soya phytoestrogens reduced brain-derived neurotrophic factor (BDNF) mRNA expression in rat brains. This suggests that oestrogen-beta receptors play a role in regulating BDNF, impacting brain health.
Area of Science:
- Neuroscience
- Endocrinology
- Molecular Biology
Background:
- Phytoestrogens are plant compounds that can interact with estrogen receptors.
- Estrogen receptors, particularly estrogen-beta (ERβ), are involved in various brain functions.
- Brain-derived neurotrophic factor (BDNF) is crucial for neuronal survival, growth, and plasticity.
Purpose of the Study:
- To investigate the effect of dietary soya phytoestrogens on BDNF mRNA expression in the rat brain.
- To explore the potential role of estrogen-beta receptors in mediating these effects.
Main Methods:
- Adult male hooded Lister rats were fed either a soya-phytoestrogen-containing diet or a soya-free diet for 18 days.
- In situ hybridization was used to quantify mRNA expression levels.
- Specific genes analyzed included BDNF, glutamic acid decarboxylase-67, and glial fibrillary acidic protein.
Main Results:
- Rats fed the phytoestrogen diet showed significant reductions in BDNF mRNA expression in the hippocampus (CA3 and CA4 regions) and cerebral cortex.
- No significant changes were observed in glutamic acid decarboxylase-67 or glial fibrillary acidic protein mRNA expression.
- The concentration of phytoestrogens used was expected to activate ERβ but not ERα.
Conclusions:
- Dietary soya phytoestrogens can downregulate BDNF mRNA expression in specific brain regions.
- These findings suggest a functional role for estrogen-beta receptors in the regulation of BDNF mRNA.
- This highlights a potential mechanism by which dietary compounds can influence neurotrophic factor expression and brain function.
