EFFECTS OF AGE AND OVARIAN FACTORS ON THE EVALUATION OF HYPOTHALAMIC CELLS INVOLVED IN THE REPRODUCTIVE CONTROL OF MICES.

• Grant number: 23/06913-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2023
• End date: May 31, 2024
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Jose Donato Junior
• Grantee: Ana Lucrécia de Oliveira Silva
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 13/07607-8 - OCRC - Obesity and Comorbidities Research Center, AP.CEPID

Abstract

Reproduction plays a fundamental role in the maintenance of species, making it important to understand aspects involving reproductive processes. In the hypothalamus, nuclei such as the hypothalamic arcuate (ARH), anteroventral periventricular, and anterior periventricular (AVPV/PeN) nuclei are prominent in controlling reproduction. These nuclei contain neurons expressing the leptin receptor (LepR), or neurons expressing the Kiss1 gene, and these are essential interneurons in modulating the hypothalamic-gonadal-pituitary axis. The objective of this project is to evaluate if age and/or ovarian factors are sufficient to modulate the number of cells of the ARH and AVPV/PeN, as well as, the coexpression with classical neurotransmitters of the respective nuclei. Genetically modified animals expressing the CRE recombinase enzyme over the transcriptional control of the gene encoding LepR, or animals expressing the hrGFP enzyme over the Kiss1 gene control will be selected for the experiments. Adult (12-16 weeks) and senescent (74-80 weeks) females will undergo ovariectomy or be kept intact (control). At the respective ages the animals will be perfused, have their encephalons removed and submitted to coronal cuts. The quantification of neurons expressing LepR or Kiss1 gene in the ARH and AVPV/PeN nuclei will be performed, as well as the coexpression of these neurons with neurotransmitters of interest. This study may indicate whether conditions such as age or ovariectomy can induce neural changes in regions responsible for reproductive control, and which neurons may be affected.