Alam M S, Ohsako S, Tay T W, Tsunekawa N, Kanai Y, Kurohmaru M
Department of Veterinary Anatomy, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.
Anat Histol Embryol. 2010 Jun;39(3):186-93. doi: 10.1111/j.1439-0264.2010.00993.x. Epub 2010 Mar 11.
Phthalate esters have been extensively used as a plasticizer of synthetic polymers. Previous studies have revealed that some phthalate esters including di(n-butyl) phthalate (DBP) induce spermatogenic cell apoptosis, although its mechanism is not yet clear. The present study describes that disruption of Sertoli cell vimentin filaments by DBP administration may relate to spermatogenic cell apoptosis. The present histopathological study revealed that a single oral administration of 500 mg/kg DBP caused progressive detachment and displacement of spermatogenic cells away from the seminiferous epithelium and sloughing of them into the lumen. Degenerative spermatogenic cells characterized by chromatin condensation were frequently observed in DBP-treated rats. Ultrastructurally, the degenerative spermatogenic cells were separated from their neighbours, and a collapse of Sertoli cell vimentin filaments was recognized in DBP-treated rats. Sertoli cell cultures showed the increased number and size of vacuoles in their cytoplasm. In agreement with the in vivo experiment, vimentin filaments clearly showed a gradual collapse in DBP-exposed Sertoli cells in vitro. These in vivo and in vitro experiments indicate that DBP-induced collapse of Sertoli cell vimentin filaments may lead to detachment of spermatogenic cells, and then detached cells may undergo apoptosis because of loss of the support and nurture provided by Sertoli cells.
邻苯二甲酸酯已被广泛用作合成聚合物的增塑剂。先前的研究表明，一些邻苯二甲酸酯，包括邻苯二甲酸二丁酯（DBP），可诱导生精细胞凋亡，但其机制尚不清楚。本研究表明，给予DBP破坏支持细胞波形蛋白丝可能与生精细胞凋亡有关。目前的组织病理学研究显示，单次口服500mg/kg DBP会导致生精细胞逐渐从生精上皮脱离和移位，并使其脱落到管腔中。在DBP处理的大鼠中经常观察到以染色质浓缩为特征的退行性生精细胞。在超微结构上，退行性生精细胞与其相邻细胞分离，并且在DBP处理的大鼠中观察到支持细胞波形蛋白丝的塌陷。支持细胞培养显示其细胞质中液泡的数量和大小增加。与体内实验一致，在体外，波形蛋白丝在暴露于DBP的支持细胞中明显显示出逐渐塌陷。这些体内和体外实验表明，DBP诱导的支持细胞波形蛋白丝塌陷可能导致生精细胞脱离，然后脱离的细胞可能由于失去支持细胞提供的支持和滋养而发生凋亡。
