Mastrorocco Antonella, Temerario Letizia, Vurchio Valeria, Cotecchia Susanna, Martino Nicola Antonio, Dell'Aquila Maria Elena
Department of Biosciences, Biotechnology and Environment, University of Bari Aldo Moro, 70125 Bari, Italy.
Int J Mol Sci. 2024 Dec 24;26(1):5. doi: 10.3390/ijms26010005.
Di-(2-ethylhexyl) phthalate (DEHP) and Cadmium (Cd) affect female reproduction. To date, toxicological research has focused on the effects of individual contaminants, whereas living beings are exposed to mixtures. This study analyzed the effects of a DEHP/Cd mixture on nuclear and cytoplasmic maturation of sheep cumulus-oocyte complexes (COCs) compared with single compounds. COCs recovered from slaughterhouses-derived sheep ovaries were in vitro exposed to 0.5 μM DEHP, 0.1 μM Cd, or DEHP/Cd mixture at the same concentrations during 24 h of in vitro maturation (IVM). After IVM, oocyte nuclear chromatin configuration was evaluated, and bioenergetic/oxidative parameters were assessed on expanded cumulus cells (CCs) and matured oocytes (chi-square test and one-way ANOVA; < 0.05). Under examined conditions, oocyte nuclear maturation was never impaired. However, COC bioenergetics was affected with stronger effects for the mixture than single compounds. Indeed, the percentages of matured oocytes with healthy mitochondrial distribution patterns were reduced ( < 0.001 and < 0.05 for mixture and single compounds, respectively). Oocyte mitochondrial membrane potential, intracellular ROS levels, and mitochondria/ROS co-localization were reduced, with the same significance level, in all contaminated conditions. CCs displayed increased ROS levels only upon mixture exposure ( < 0.001). In conclusion, in vitro exposure to the DEHP/Cd mixture affected COC quality in the sheep to a greater extent than separate compounds.
邻苯二甲酸二（2-乙基己基）酯（DEHP）和镉（Cd）会影响雌性生殖。迄今为止，毒理学研究主要集中在单一污染物的影响上，而生物实际接触的是混合物。本研究分析了DEHP/Cd混合物与单一化合物相比对绵羊卵丘-卵母细胞复合体（COC）核成熟和胞质成熟的影响。从屠宰场获得的绵羊卵巢中回收的COC在体外成熟（IVM）的24小时内，分别暴露于0.5μM DEHP、0.1μM Cd或相同浓度的DEHP/Cd混合物中。IVM后，评估卵母细胞核染色质构型，并对扩张的卵丘细胞（CCs）和成熟卵母细胞评估生物能量/氧化参数（卡方检验和单因素方差分析；P<0.05）。在所研究的条件下，卵母细胞核成熟从未受到损害。然而，COC的生物能量学受到了影响，混合物的影响比单一化合物更强。实际上，具有健康线粒体分布模式的成熟卵母细胞百分比降低（混合物和单一化合物分别为P<0.001和P<0.05）。在所有受污染条件下，卵母细胞线粒体膜电位、细胞内活性氧水平和线粒体/活性氧共定位均降低，且具有相同的显著水平。只有在暴露于混合物时，CCs的活性氧水平才会升高（P<0.001）。总之，体外暴露于DEHP/Cd混合物对绵羊COC质量的影响比单独的化合物更大。
