Department of Anatomy and Cell Biology, University of Marburg, Marburg, Germany.
Histochem Cell Biol. 2011 Oct;136(4):413-25. doi: 10.1007/s00418-011-0832-0. Epub 2011 Sep 7.
Peroxisomes are organelles with main functions in the metabolism of lipids and of reactive oxygen species. Within the testis, they have different functional profiles depending on the cell types. A dysfunction of peroxisomes interferes with regular spermatogenesis and can lead to infertility due to spermatogenic arrest. However, so far only very little is known about the functions of peroxisomes in germ cells. We have therefore analyzed the peroxisomal compartment in germ cells and its alterations during spermatogenesis by fluorescence and electron microscopy as well as by expression profiling of peroxisome-related genes in purified cell populations isolated from mouse testis. We could show that peroxisomes are present in all germ cells of the germinal epithelium. During late spermiogenesis, the peroxisomes form large clusters that are segregated from the spermatozoa into the residual bodies upon release from the germinal epithelium. Germ cells express genes for proteins involved in numerous metabolic pathways of peroxisomes. Based on the expression profile, we conclude that newly identified functions of germ cell peroxisomes are the synthesis of plasmalogens as well as the metabolism of retinoids, polyunsaturated fatty acids and polyamines. Thus, germ cell peroxisomes are involved in the regulation of the homeostasis of signaling molecules regulating spermatogenesis and they contribute to the protection of germ cells against oxidative stress.
过氧化物酶体是具有脂质和活性氧代谢主要功能的细胞器。在睾丸中，它们根据细胞类型具有不同的功能特征。过氧化物酶体的功能障碍会干扰正常的精子发生，并可能导致不育，因为精子发生停滞。然而，到目前为止，人们对生殖细胞中的过氧化物酶体的功能知之甚少。因此，我们通过荧光和电子显微镜以及从小鼠睾丸中分离的纯化细胞群体中转录组分析了生殖细胞中的过氧化物酶体区室及其在精子发生过程中的变化。我们可以证明过氧化物酶体存在于生殖上皮的所有生殖细胞中。在晚期精子发生过程中，过氧化物酶体形成大的簇，在从生殖上皮释放时与精子一起被隔离到残余体中。生殖细胞表达参与过氧化物酶体多种代谢途径的蛋白质的基因。基于表达谱，我们得出结论，生殖细胞过氧化物酶体的新鉴定功能是磷脂的合成以及视黄醇、多不饱和脂肪酸和多胺的代谢。因此，生殖细胞过氧化物酶体参与调节调节精子发生的信号分子的动态平衡，并有助于保护生殖细胞免受氧化应激。
