The subtypes of zona pellucida (zp), primarily expressed in female gonads, are considered novel molecular markers for testis-ova (or intersex), a type of gonadal abnormality caused by environmental estrogens (EEs) in Japanese medaka (Oryzias latipes). However, the association between testis-ova and the expression of gonadal zp subtypes is unclear in other teleost species, particularly in species studied in field surveys. In this study, 17α-ethinylestradiol (EE2) was orally administrated at 4–4000 ng/g body weight (BW)/day for 28 days to gray mullets (Mugil cephalus), and gonadal abnormalities were studied using histological analysis. The expression profiles of gonadal zp subtypes (zpb and zpc5) were analyzed to evaluate their suitability as gonadal abnormality markers by comparing with a hepatic vitellogenin (vtg) subtype (vtgAb). The oral administration of EE2 40 and 400 ng/g BW/day for 28 days induced significant gonadal zpb expression, and the gonads showed moderate abnormality (testis-ova). Conversely, the gonadal zpc5 levels decreased significantly in response to the oral administration of EE2 at 4000 ng/g BW/day for 28 days, and the gonads exhibited severe abnormalities. The hepatic vtgAb levels increased upon EE2 treatment regardless of gonadal abnormality. Therefore, the gonadal zpb levels and hepatic vtgAb levels served as appropriate markers for testis-ova and EE2 presence, respectively. However, the diagnosis of severe gonadal abnormality using gonadal zpc5 was moderately accurate. The findings suggest that the combination of vtgAb, zpb, and zpc5 is a potential marker for gonadal abnormality caused by EE contamination in gray mullet. That said, the potential of zpc5 should be reconsidered to determine if it shows greater accuracy in a larger or more diverse population.

主要在雌性性腺中表达的透明带 ( zp )亚型被认为是睾丸卵 (或双性人) 的新型分子标记，这是一种由日本青鳉 ( Oryzias latipes ) 中的环境雌激素 (EE) 引起的性腺异常。然而，睾丸卵子与性腺zp亚型表达之间的关联在其他硬骨鱼物种中尚不清楚，特别是在实地调查中研究的物种中。在这项研究中，17α-炔雌醇 (EE2) 以 4–4000 ng/g 体重 (BW)/天的剂量口服给药至鲻鱼 ( Mugil cephalus )，持续 28 天，并使用组织学分析研究性腺异常。性腺zp亚型 ( zpb通过与肝卵黄蛋白原 ( vtg ) 亚型 ( vtgAb )进行比较，分析和zpc5 ) 以评估它们作为性腺异常标志物的适用性。EE2 40 和 400 ng/g BW/day 的口服给药 28 天诱导了显着的性腺zpb表达，性腺显示出中度异常（睾丸 - 卵子）。相反，在以 4000 ng/g BW/天口服 EE2 28 天后，性腺zpc5水平显着降低，性腺表现出严重异常。无论性腺异常如何，EE2 治疗后肝脏vtgAb水平都会增加。因此，性腺zpb水平和肝脏vtgAb水平分别作为睾丸 ova 和 EE2 存在的适当标记。然而，使用性腺zpc5对严重性腺异常的诊断是中等准确的。研究结果表明，vtgAb、zpb和zpc5的组合是灰鲻鱼 EE 污染引起的性腺异常的潜在标志物。也就是说，应该重新考虑zpc5的潜力，以确定它是否在更大或更多样化的人群中显示出更高的准确性。