Effects of High-Glucose and High-Fat Condition on Estrogen Receptor- and Sexual Precocity-Related Genes in GT1-7 Cells

Abstract

Departmental sources Background:This study was designed to investigate the effect of high-glucose and high-fat condition on estrogen receptorand sexual precocity-related genes in GT1-7 cells. Material/Methods:In this study, CCK8 was used to detect cell viability, and TUNEL assay was used to detect apoptosis levels of GT1-7 cells after treatment with glucosamine and palmitate. The expression level of GnRH was measured by ELISA and RT-qPCR. RT-qPCR and Western blot were used to detect the expression of ERb, CD36, and GPR54 in GT1-7 cells, and the expression of ERb was detected using immunohistochemistry analysis. Finally, after adding the intervening drug tamoxifen to GT1-7 cells, the expression level of GnRH was measured by ELISA and Western blot analysis was used to detect the expression of GPR54 and GnRH. Results:GnRH secretion in the high-fat and high-glucose group increased continuously over time and peaked at 18 h, and GnRH gene expression peaked at 12 h. High-fat and high-glucose conditions also significantly increased the levels of estrogen receptors b (ERb), fatty acid translocase protein (CD36), and G Protein-Coupled Receptors 54 (GPR54) in GT1-7 cells. After estrogen receptors b (ER) was inhibited, GnRH secretion and GPR54 expression were decreased at 12 h and 18 h. Conclusions:Our study demonstrates that high-glucose and high-fat conditions promote the secretion of GnRH and ER and the expression of genes related to sexual precocity in GT1-7 cells.

LKB1 alleviates high glucose‑ and high fat‑induced inflammation and the expression of GnRH and sexual precocity‑related genes, in mouse hypothalamic cells by activating the AMPK/FOXO1 signaling pathway

“…ICPP can lead to metabolic abnormalities and affect the central nervous system. It has been shown that a HG and HF diet can affect the expression of ER- and PP-related genes in hypothalamic cells ( 7 ). In the present study, a HG- and HF-induced GT1-7 mouse hypothalamic cell line was used as the PP in vitro model to simulate the physiological environment of PP in the body, as previously described ( 7 ).…”

“…It has been shown that a HG and HF diet can affect the expression of ER- and PP-related genes in hypothalamic cells ( 7 ). In the present study, a HG- and HF-induced GT1-7 mouse hypothalamic cell line was used as the PP in vitro model to simulate the physiological environment of PP in the body, as previously described ( 7 ). The role of LKB1 in the progression of PP in this in vitro model was also explored.…”

“…Estrogen and its receptors adjust the synthesis and release of GnRH by acting on GnRH neurons in the hypothalamus, thereby regulating the entire reproductive system ( 23 ). ERβ, CD36 and GPR54 are important ER- and sexual precocity-related genes, which have been shown to be expressed in GT1-7 cells ( 7 ). The present study showed that the expression of ERβ, CD36 and GPR54 was clearly decreased following LKB1 overexpression in GT1-7 cells under HG and HF conditions, compared with the control group, which was in line with a previous study performed by Wang et al ( 7 ).…”

“…Cells in the control group were maintained in complete DMEM (glucose concentration, 25 mM). The HG and HF group cells were cultured in DMEM plus 45 mM glucose + 1 mM palmitate according to the previous study ( 7 ). Following incubation for 12 h, cells were collected for subsequent experiments.…”

“…Obesity is considered to be a crucial factor that triggers idiopathic central PP (ICPP) through the excessive intake of lipids and sugar, which leads to multiple metabolic disorders and further affects the central nervous system ( 6 ). Compelling evidence indicates that high levels of sugar and fat can regulate the expression of estrogen receptor (ER) and PP-related genes in hypothalamic cells ( 7 ). Live kinase B1 (LKB1), also known as serine/threonine kinase 11 (STK11), is a serine-threonine kinase that participates in several cellular functions, including growth, cell energy metabolism, polarity and tumor formation ( 8 ).…”