Morphological rearrangement of the cortical region, in aging ovaries
Verónica Díaz-Hernández1, Ivette Caldelas2, Luis M. Montaño3 and Horacio Merchant-Larios2
1Department of Embriology, Faculty of Medicine, 2Department of Cellular Biology and Physiology, Institute of Biomedical Research and 3Department of Pharmacology, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico
Offprint requests to: Verónica Díaz-Hernández, Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP. 04510, Ciudad de México, Mexico. e-mail: roveazdih@yahoo.com.mx
Summary. The ovary is a structurally dynamic organ that alters with age. Modifications in the paracrine status influence the capacity of aging oocytes to develop normal embryos. Despite the importance of understanding the cellular and molecular mechanism involved in the process of ovarian aging, histological changes remain poorly understood. Correlating the process of folliculogenesis and somatic cell function during ovarian aging is essential to explain the reproductive decline of aged mammalian species, including humans.
Here, we performed a morphological and immunohistological study on the ovaries of chinchilla rabbits that varied in age from one to 34-months. The spatiotemporal expression of the cholesterol side-chain cleavage cytochrome P450scc (CYP11A) and the smooth muscle actin (SMA) were analyzed.
A significant histological rearrangement of immunodetected cells in theca interna, theca externa and the interstitial tissue around the follicles occurred. The expression of CYP11A1 decreased considerably in antral follicles of aging ovaries. Moreover, we found that the secondary interstitial gland developed extensively, and a remarkable rearrangement of the surface epithelium occurred in aging ovaries. In contrast to ovaries during the reproductive period, the immunohistological changes demonstrate that the interstitial gland became the most abundant tissue during the aging of ovaries. Thus, the current study provides new data for understanding the alteration of somatic cell function in elderly ovaries and how this affects their declined fertility. Histol Histopathol 34, 775-789 (2019)
Key words: Aging ovary, Interstitial gland, Theca cells, Cyp11a1, Smooth muscle actin
DOI: 10.14670/HH-18-078