Age-related changes in gene expression patterns of immature and aged rat primordial follicles

Abstract

Women are born with millions of primordial follicles which gradually decrease with increasing age and this irreversible supply of follicles completely exhausts at menopause. The fertility capacity of women diminishes in parallel with aging. The mechanisms for reproductive aging are not fully understood. We have observed a decline in Brca1 mediated DNA repair in aging rat primordial follicles. To further understand the age-related molecular changes, we performed microarray gene expression analysis using total RNA extracted from immature (18 to 20 day old) and aged (400 to 450 day old) rat primordial follicles. The results of current microarray study revealed that there were 1,011 (>1.5 fold, p<0.05) genes differentially expressed between two groups in which 422 genes were up-regulated and 589 genes were down-regulated in aged rat primordial follicles compared to immature primordial follicles. The gene ontology and pathway analysis of differentially expressed genes revealed a critical biological function such as cell cycle, oocyte meiosis, chromosomal stability, transcriptional activity, DNA replication, and DNA repair were affected by age. This considerable difference in gene expression profiles may have an adverse influence on oocyte quality. Our data provide information on the processes that may contribute to aging and age-related decline in fertility.

Circular RNAs are temporospatially regulated throughout development and ageing in the rat

“…MiRNA are differentially expressed during ageing in a tissue-specific manner in both humans and rodents 29–32 , suggesting that these molecules modify target genes that are active in ageing-related pathways 32 . Ageing was also linked to a substantial alteration in gene expression in various tissues of mammals and human 14,33–35 . Comprehensive analysis of transcriptomic activities indicated a differential expression of mRNA across the life cycle of the rat in various organs 21 .…”

What Changed on the Folliculogenesis in the Process of Mouse Ovarian Aging?

“…The gradual decrease of both the quantity and the quality of the oocytes surrounded by the granulosa cells in all stages of follicles dominates the reproductive aging [4]. In previous study, Govindaraj et al revealed that gene expression patterns changed considerably in the rat primordial follicles in the process of ovarian aging [25]. Folliculogenesis in the ovary is a highly dynamic and periodic process regulated by both intra- and extra-oocyte factors [26].…”

Dynamic Changes of DNA Methylation and Transcriptome Expression in Porcine Ovaries during Aging

“…In other genetic systems, it has been reported that several RNA species play critical roles in the regulation of ovarian physiology, and these RNA species are involved in protein-coding RNAs [79–81] and noncoding RNAs such as miRNAs [12–14] and lncRNAs [15, 16]. The current study presents the global transcriptome expression profile of ovarian aging and identified a large number of differentially expressed RNAs.…”