Prenatal Exposure to Bisphenol A, E, and S Induces Transgenerational Effects on Female Reproductive Functions in Mice

This study was performed to examine the transgenerational effects of bisphenol (BP) A analogs, BPE, and BPS on female reproductive functions using mice as a model. CD-1 mice (F0) were orally exposed to control treatment (corn oil), BPA, BPE, or BPS (0.5 or 50 µg/kg/day) from gestational day 7 (the presence of vaginal plug = 1) to birth. Mice from F1 and F2 offspring were used to generate F3 females. Prenatal exposure to BPA, BPE, and BPS accelerated the onset of puberty and exhibited abnormal estrous cyclicity in F3 females, and those females exhibited mating difficulties starting at 6 months of age. Various fertility problems including reduced pregnancy rates, parturition, and nursing issues were also observed starting at 6 months, which worsened at 9 months. The levels of serum estradiol-17β were elevated by BPA or BPS exposure at the age of 6 months, whereas testosterone levels were not affected. The dysregulated expression of steroidogenic enzymes was observed in the ovary at 3 or 6 months of age by BPE or BPS exposure. However, BPA, BPE, and BPS exposure did not affect neonatal follicular development such as germ cell nest breakdown or follicle numbers in the ovary on postnatal day 4. These results suggest that prenatal exposure to BPA analogs, BPE and BPS, have transgenerational effects on female reproductive functions in mice.

IDENTIFIKASI PROTEIN PENENTU IMPLANTASI EMBRIO PADA TIKUS WISTAR (Rattus norvegicus)

Penelitian dengan tujuan mengidentifikasi protein penentu implantasi embrio pada tikus Wistar (Rattus norvegicus) dilakukan sebagai upaya eksplorasi agen imunokontrasepsi baru untuk regulasi fertilitas hewan liar. Hewan uji yang digunakan adalah tikus Wistar betina dewasa kelamin dengan bobot badan berkisar 280-300 g. Tikus dibagi dalam dua kelompok, satu kelompok sebagai kontrol (tidak dikawinkan) sedangkan kelompok lain adalah kelompok yang dikawinkan. Tikus dipelihara dan dikawinkan dalam kondisi laboratorium yang terkontrol. Kebuntingan ditentukan dengan adanya vaginal plug pada tikus betina setelah dikawinkan. Protein diisolasi dari sampel uterus yang diambil pada umur kebuntingan 3-5 hari. Isolasi dan separasi protein dilakukan berdasarkan manual dan standar protein produk Bio-Rad. Hasil penelitian menunjukkan pita protein yang terekspresi pada hari ke-4 kebuntingan dengan berat molekul berkisar 45 kDa diduga leukemia inhibitory factor.

165 EXPRESSION OF CALCIUM TRANSPORTER 1 GENE IN THE UTERUS OF RATS DURING PREGNANCY

Calcium Transporter 1 (CaT1), which is highly expressed in calcium-absorption organs, i.e. duodenum and kidney, is a critical mediator for calcium uptake during transcellular calcium transport. It has been shown that CaT1 gene is also expressed in the placenta and uterine smooth muscle in female reproductive organs. We previously demonstrated that uterine CaT1 mRNA is highly expressed at diestrus and tightly regulated by progesterone (P4) related to calcium homeostasis for uterine functions during the estrous cycle in rats. Thus, in the recent study, we further examined the expression of CaT1 mRNA in the uterus and placenta of rats to elucidate its role during pregnancy in these tissues. Female Sprague Dawley rats (n = 2) were employed and their pregnancy days (PD) were determined by a vaginal plug every morning; the rats were euthanized daily (PD 0 to 21). The expression of CaT1 mRNA decreased from PD 0 to 4 and highly increased on PD 5 to 10. Its increased transcripts gradually decreased at the end of pregnancy. Taken together, these results indicate that the expression level of CaT1 mRNA is regulated in the uterus of rats during pregnancy, probably via sex steroid hormones and their receptors through a complex pathway. A further study is warranted to verify relevant factors which regulate CaT1 gene and to provide further insight into its role(s) in the female reproductive tissues.

Secreted phosphoprotein 1 (osteopontin) is expressed by stromal macrophages in cyclic and pregnant endometrium of mice, but is induced by estrogen in luminal epithelium during conceptus attachment for implantation

Secreted phosphoprotein 1 (SPP1, osteopontin) is the most highly upregulated extracellular matrix/adhesion molecule/cytokine in the receptive phase human uterus, and Spp1 null mice manifest decreased pregnancy rates during mid-gestation as compared with wild-type counterparts. We hypothesize that Spp1 is required for proliferation, migration, survival, adhesion, and remodeling of cells at the conceptus–maternal interface. Our objective was to define the temporal/spatial distribution and steroid regulation of Spp1 in mouse uterus during estrous cycle and early gestation.In situhybridization localizedSpp1to luminal epithelium (LE) and immune cells. LE expression was prominent at proestrus, decreased by estrus, and was nearly undetectable at diestrus. During pregnancy,Spp1mRNA was not detected in LE until day 4.5 (day 1 = vaginal plug).Spp1-expressing immune cells were scattered within the endometrial stroma throughout the estrous cycle and early pregnancy. Immunoreactive Spp1 was prominent at the apical LE surface by day 4.5 of pregnancy and Spp1 protein was also co-localized with subsets of CD45-positive (leukocytes) and F4/80-positive (macrophages) cells. In ovariectomized mice, estrogen, but not progesterone, inducedSpp1mRNA, whereas estrogen plus progesterone did not induceSpp1in LE. These results establish that estrogen regulates Spp1 in mouse LE and are the first to identify macrophages that produce Spp1 within the peri-implantation endometrium of any species. We suggest that Spp1 at the apical surface of LE provides a mechanism to bridge conceptus to LE during implantation, and that Spp1-positive macrophages within the stroma may be involved in uterine remodeling for conceptus invasion.

EFEK EKSTRAK TESTIS TERHADAP JUMLAH IMPLANTASI DAN JUMLAH ANAK PADA MENCIT (Mus musculus)

Extract of testis contains the testis specific proteins. The testis proteins may raise immune responses. The immune responses are the antibodies against testis specific anti-protein. The reaction between the antibodies and the sperms can inhibit fertilization. This process has contraception effects. This research used 24 female and 20 male mice strain Balb/c. The experiment used the complete random design with 4 concentration treatments (0, 500, 1000, and 2000 μg extracts of testis) and 3 replications. Mice were injected 3 times with time interval 21 days. After 15 days from the rising of vaginal plug, 3 mice were dissected and counted the implantation. The others mice were waited until delivered of the children. The datas were analyzed by ANOVA and LSD (a = 5 percent). The results showed that extract of testis did not influence the amount of implantation at the uterus endometrial, but it decreased the amount of children. The effective concentration of extract testis is 2000 μg. So, this study showed that the intraperitoneum injection of the extract of testis had contraception effects.