4-Bromodiphenyl ether delays pubertal Leydig cell development in rats

Area of Science:

• Endocrinology
• Toxicology
• Reproductive Biology

Background:

• Polybrominated diphenyl ethers (PBDEs) are flame retardants with endocrine-disrupting potential.
• 4-Bromodiphenyl ether (BDE-3) is a major photodegradation product of PBDEs.
• The impact of BDE-3 on pubertal Leydig cell development remains largely unknown.

Purpose of the Study:

• To investigate the effects of BDE-3 on the pubertal development of rat Leydig cells.
• To elucidate the molecular mechanisms underlying BDE-3-induced disruption.

Main Methods:

• Male Sprague Dawley rats (35 days old) were administered daily oral doses of BDE-3 (0, 50, 100, 200 mg/kg) for 21 days.
• In vitro studies exposed immature Leydig cells to BDE-3 for 24 hours.
• Assessed serum testosterone, Leydig cell morphology, gene expression (mRNA), protein phosphorylation, and reactive oxygen species (ROS) generation.

Main Results:

• BDE-3 exposure significantly decreased serum testosterone levels in a dose-dependent manner.
• Reduced Leydig cell size, cytoplasmic volume, and expression of key genes (Lhcgr, Star, Dhh, Sox9, Scarb1, Cyp11a1, Hsd17b3, Fshr).
• Inhibited phosphorylation of AKT1, AKT2, ERK1/2, and AMPK; induced ROS generation; and suppressed androgen production in vitro.

Conclusions:

• BDE-3 disrupts pubertal Leydig cell development in rats.
• Mechanisms involve suppression of AKT, ERK1/2, and AMPK signaling pathways.
• Increased oxidative stress (ROS generation) contributes to BDE-3 toxicity in Leydig cells.