AREG upregulates secreted protein acidic and rich in cysteine expression in human granulosa cells. (5th February 2023)

• Record Type: Journal Article
• Authors: Dang, Xuan; Fang, Lanlan; Zhang, Qian; Liu, Boqun; Cheng, Jung-Chien; Sun, Ying-Pu
• Is Part Of: Molecular and cellular endocrinology. Volume 561(2023)
• Publication Date: 2023-02-05
• Subjects: AREG -- SPARC -- StAR -- Progesterone -- Granulosa cells; Endocrinology -- Periodicals; Molecular biology -- Periodicals; Cytology -- Periodicals; Endocrinology -- Periodicals; Hormones -- Periodicals; Endocrinologie -- Périodiques; Cytology; Endocrinology; Molecular biology; Periodicals; 573.4
• DOI: 10.1016/j.mce.2022.111826
• Languages: English
• ISSNs: 0303-7207

Abstract

Abstract: The secreted protein acidic and rich in cysteine (SPARC) is a secreted glycoprotein and the expression of ovarian SPARC peaks during ovulation and luteinization. Besides, SPARC expression was induced by human chorionic gonadotropin (hCG) in rat granulosa cells. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) ligand expressed in human granulosa cells and follicular fluid. AREG mediates the physiological functions of luteinizing hormone (LH)/hCG in the ovary. However, to date, the biological function of SPARC in the human ovary remains undetermined, and whether AREG regulates SPARC expression in human granulosa cells is unknown. In this study, we show that AREG upregulated SPARC expression via EGFR in a human granulosa-like tumor cell line, KGN. Treatment of AREG activated ERK1/2, JNK, p38 MAPK, and PI3K/AKT signaling pathways and all of them were required for the AREG-induced SPARC expression. Using RNA-sequencing, we identified that steroidogenic acute regulatory protein (StAR) was a downstream target gene of SPARC. In addition, we demonstrated that SPARC mRNA levels were positively correlated with the levels of StAR mRNA in the primary culture of human granulosa cells. Moreover, SPARC protein levels were positively correlated with progesterone levels in follicular fluid of in vitro fertilization patients. This study provides the regulatory role of AREG on the expression of SPARC and reveals the novel function of SPARC in progesterone production in granulosa cells. Highlights: AREG upregulates SPARC expression via EGFR. ERK1/2, JNK, p38 MAPK, and PI3K/AKT signaling pathways are involved in AREG-induced SPARC expression. SPARC knockdown downregulates StAR expression. SPARC mRNA levels are positively correlated with StAR mRNA levels in primary hGL cells. SPARC protein levels are positively correlated with progesterone levels in follicular fluid.