Evaluation of the expression of glutamatergic receptors in the cerebellum in a cellular model of Klotho deletion: possible modulatory role of beta-estradiol

• Grant number: 24/07231-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: December 01, 2024
• End date: July 31, 2026
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Elisa Mitiko Kawamoto Iwashe
• Grantee: Geovana Rosa Oliveira dos Santos
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 21/06009-6 - Neuroplasticity -induced by challenge Na, K-ATPase, Klotho, glutamate, and neuroinflammation signaling cascades to reveal new therapeutic targets for aging and neurodegenerative diseases, AP.TEM

Abstract

The Klotho protein is involved in the aging process and in some cellular and molecular processes in the central nervous system (CNS). In the CNS, Klotho is synthesized by ependymal cells of the choroid plexus, Purkinje cells, and hippocampal neurons, and participates in some cognitive processes related to memory and in the regulation of synaptic plasticity in the hippocampus. At the cellular level, Klotho has a protective role in hippocampal neurons and cerebellar granule cells. Klotho expression differs between the sexes, as male mice have higher Klotho expression in the cerebral cortex and cerebellum compared to female. The glutamatergic receptors N-methyl-D-aspartate (NMDA) and ¿-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) participate in synaptic plasticity mechanisms and in the induction and maintenance of long-term potentiation (LTP) and long-term depression (LTD). A previous study showed that Klotho-hypomorphic male mice exhibit reduced protein expression of GluA1 (AMPA) in the cerebellum compared to Klotho-wild-type males and Klotho-hypomorphic females. ¿-estradiol acts in the regulation of some functions in the CNS, such as dendritic growth and modulation of glutamatergic neurotransmission-associated pathways. Therefore, the objective is to investigate whether there are changes in the expression of NMDA and AMPA receptor subunits, through Western Blotting, and in neuronal morphology, based on immunofluorescence, in primary mixed culture of cerebellum from male and female neonatal rats with Klotho protein gene deletion, through transfection of silencing RNA (siRNA-Klotho), and whether pre-exposure to ¿-estradiol has a modulatory role towards Klotho deletion on the expression of these receptors and neuronal morphology.