Molecular Biology and Reproductive Immunology Laboratory, School of Studies in Biochemistry, Jiwaji University, Gwalior, India.
Biol Reprod. 2013 Jun 27;88(6):162. doi: 10.1095/biolreprod.113.108068. Print 2013 Jun.
The objective of the present study is to investigate the role of heat shock proteins (Hsps) in preimplantation embryonic development and uterine receptivity during lipopolysaccharide (LPS)-induced pregnancy loss. Mice were treated with PBS or LPS on Day 0.5 of pregnancy, and preimplantation embryos and uterus were collected on Days 1.5-4.42 of pregnancy. The individual preimplantation embryos were assessed for their morphologic appearance and DNA damage during the preimplantation period of pregnancy. The expression of Hsp90, Hsp70, Hsp60, and Hsp25 was determined in preimplantation embryos and uterus by RT-PCR. Comet studies showed that LPS treatment significantly increased the percentage of abnormal embryos and DNA damage in the embryos. The expression of Hsp90, Hsp70, and Hsp60 was significantly lower in preimplantation embryos recovered from LPS-treated mice when compared to their respective controls. The expression of Hsp90, Hsp70, Hsp60, and Hsp25 was altered in uterus of LPS-treated mice when compared to their respective controls. Immunohistochemistry studies showed that at the time of implantation (i.e., Day 4.42), levels of Hsp90 and Hsp60 were decreased in stromal cells of LPS-treated uterus when compared to their respective controls. Hsp25 was highly expressed in the endometrium and stromal cells of LPS-treated uterus. Our results clearly showed that lowering of embryonic expression of Hsps induces DNA damage, which leads to degeneration and degradation of preimplantation embryos, and altered uterine expression of Hsps may not prepare the uterus for implantation. This may ultimately lead to implantation failure in mouse.
本研究旨在探讨热休克蛋白（Hsps）在脂多糖（LPS）诱导的妊娠丢失中对胚胎着床前发育和子宫容受性的作用。小鼠在妊娠第 0.5 天用 PBS 或 LPS 处理，并在妊娠第 1.5-4.42 天收集着床前胚胎和子宫。在胚胎着床期间评估单个着床前胚胎的形态外观和 DNA 损伤。通过 RT-PCR 确定着床前胚胎和子宫中 Hsp90、Hsp70、Hsp60 和 Hsp25 的表达。彗星研究表明，LPS 处理显著增加了胚胎中异常胚胎和 DNA 损伤的百分比。与各自的对照相比，从 LPS 处理的小鼠中回收的着床前胚胎中 Hsp90、Hsp70 和 Hsp60 的表达明显降低。与各自的对照相比，LPS 处理的小鼠子宫中 Hsp90、Hsp70、Hsp60 和 Hsp25 的表达发生改变。免疫组织化学研究表明，在着床时（即第 4.42 天），与各自的对照相比，LPS 处理的子宫基质细胞中 Hsp90 和 Hsp60 的水平降低。Hsp25 在 LPS 处理的子宫的子宫内膜和基质细胞中高度表达。我们的研究结果清楚地表明，胚胎中 Hsps 的表达降低会导致 DNA 损伤，从而导致着床前胚胎退化和降解，并且子宫中 Hsps 的表达改变可能不会为着床做好准备。这可能最终导致小鼠着床失败。
