Development of adrenal cortical zonation and expression of key elements of adrenal androgen production in the chimpanzee (Pan troglodytes) from birth to adulthood

Abstract

The basis for the pattern of adrenal androgen production in the chimpanzee, which resembles that of humans, is poorly defined. We characterized the developmental zonation and expression of elements of the androgen biosynthetic pathway in the chimpanzee adrenal. The newborn adrenal contained a broad fetal zone (FZ) expressing CYP17, SULT2A1, and Cytochrome b5 (CB5) but not HSD3B; the outer cortex expressed HSD3B but not SULT2A1 or CB5. During infancy, the FZ involuted and the HSD3B-expressing outer cortex broadened. By 3 years of age, a thin layer of cells that expressed CB5, SULT2A1, and CYP17 adjoined the medulla and likely represented the zona reticularis; the outer cortex consisted of distinct zonae fasiculata and glomerulosa. Thereafter, the zona reticularis broadened as also occurs in the human. The adult chimpanzee adrenal displayed other human-like characteristics: intramedullary clusters of reticularis-like cells and also a cortical cuff of zona fasiculata-like cells adjoining the central vein.

Alterations of adrenal steroidomic profiles in preterm infants at birth

“…In fetal adrenal cortex, these three zones become morphologically distinguishable during the third trimester of pregnancy. The inner or fetal zone expresses CYP11A1, CYP17 and sulfokinase activities and produces dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) 5. In the transitional zone, CYP11A1, CYP17, CYP21A2 and CYP11B1 support cortisol production.…”

DHEAS and Human Development: An Evolutionary Perspective

“…In humans the emergence of the ZR at age 3 (67) is similar to that seen in chimpanzees (134). However, the relationship of ZR emergence with the timing of molar eruption, the period of elevated synaptogenesis and weaning differ from that observed in the chimpanzee.…”

“…Examination of adrenal glands from chimpanzees suggest the ZR begins to emerge around the age of 3 years and continues to broaden into adulthood (134), similar to the pattern found in humans (67). Unfortunately, data regarding the maturation of the zona reticularis is not available for bonobos.…”

Hormones and Human and Nonhuman Primate Growth

“…The results from this comparative study suggests that similarity in human and African great ape DHEA/DHEAS levels, together with conserved promoter sequences and transcription factor binding sites in enzyme-regulatory genes key in the DHEA/DHEAS production pathway, predicted that tissue-specific expression of these enzymes would localize similarly in humans and African apes [49]. Immunostaining of chimpanzee adrenal glands, collected from autopsied individuals from birth to adulthood, shows several similarities in adrenal gland development and enzyme expression with humans, in part supporting this prediction that the patterns of circulating adrenal androgens are the result of the same tissue-specific developmental processes [50]. …”