Determination of testicular estrogen receptor alpha expression of male chickens (Gallus domesticus) with age

Abstract

Background and Aim: Estrogen activity, a central component of reproductive growth, is regulated by the receptor proteins, estrogen receptor alpha (ERα), and ER beta (ERβ) in chickens as in many other species. ERα expresses predominantly in gonads. Although the expression of ERα in embryonic gonads has been studied in detail, the expression of ERα in post-hatching male gonads has not been studied adequately. Therefore, the current research was conducted to determine the post-hatching changes in the expression of ERα in the left gonads of male chickens with age. Materials and Methods: Shaver Brown male chickens were raised and cared for according to the management guide and sacrificed at the intervals of 1, 4, and 8 weeks of age. The total RNA was extracted from the left gonads using the Trizol method and reverse transcribed using a pair of gene-specific primers. Following polymerase chain reaction amplification, the expression of ERα was quantified relative to the expression of the reference gene GAPDH. Results: The results showed that ERα expression significantly increases with age at p=0.0032. However, the increment of ERα expression from week 1 to week 4 was 2.04-fold and from week 4 to week 8 was 1.39-fold, with the later age reflecting a diminishing pattern in the increment. Conclusion: These results differentiate the post-hatching ERα expression of the left gonads of male chickens increase with age but with a diminishing gradient that may support their reproductive functions in later stages of life.

Diverse effect of in ovo treatment with metaloestrogen: selenium on chick testis histology and estrogen signaling

“…In embryonic day 5, the expression of ERα gradually diminishes in males. In adult testes and epididymides, varying amounts of ERα (highest in the testes) are present, reflecting its importance in the reproductive development of chickens during later stages of life (16,45). These findings facilitate the argument that the ERα receptor is more sex specific in chickens.…”

Water and Food restriction decreases immunoreactivity of oestrogen receptor alpha and antioxidant activity in testes of sexually mature Coturnix coturnix japonica

“…Thus, it can be said that ERα expression reduces according to the type of stress in the animals. Oestrogenic activity correlated by the presence of ERα involves not only classic genomic pathology but also membrane receptors which influence the germ cell proliferation, differentiation leading to fully mature spermatozoa (Nirmali, Warnakula, Cooray, Hapuarachchi, & Magamage, 2019). Overall, our findings indicate association of the fluctuation in endogenous oestradiol with expression of ERα influencing the testicular activity in male birds during stress.…”