The influence of mating on estrogen receptor alpha protein level in spleen and uterine macrophages in female mice

Effect of monosodium glutamate on fetal development and progesterone level in pregnant Wistar Albino rats

Monosodium glutamate (MSG) is a widespread flavor enhancer and stabilizer in manufactured or packaged foods that possess myriad adverse effects. This study aimed to evaluate the effect of MSG on placental progesterone receptors and fetal development. Thirty pregnant Wistar Albino rats were divided into three groups (ten/each). The control group (G1) gavaged distilled water only, low-dose treated group (G2) gavaged 3 g/kg MSG, and high-dose treated group (G3) gavaged 6 g/kg MSG from 1st to 18th days of gestation, and all pregnant rats were sacrificed on the 19th day of gestation. The effect of MSG on fetal weights, crown vertebral length (CVL), placental weight, placental ghrelin expression, and fetal skeleton examination were estimated. MSG induced a significant decrease in fetal weights, CVL lengths, placental weight, and ghrelin expression in both treatment groups compared to the control group. Several parts of the fetal skeleton showed incomplete ossification and delayed chondrification in which high-dose maternally treated fetuses were more affected. Many degenerative changes were detected in both maternal and fetal liver and kidney tissues in MSG-treated groups. Moreover, MSG caused a significant increase in serum ALT, ALP, and creatinine levels in pregnant rats' blood. Serum progesterone was only elevated in G3 on the 19th day of gestation. This study showed that the administration of MSG during pregnancy adversely influences fetal growth and skeletal development and caused several biochemical and histological changes in the maternal and fetal liver and kidney tissues which assure the toxic and teratogenic effects of MSG.

Gestational caffeine exposure acts as a fetal thyroid-cytokine disruptor by activating caspase-3/BAX/Bcl-2/Cox2/NF-κB at ED 20

The objective of this examination was to explore the impact of gestational caffeine (1,3,7-trimethylxanthine) exposure on the maternofetal thyroid axis and fetal thyroid-cytokine communications during gestation. Pregnant rats (Rattus norvegicus) were intraperitoneally administered caffeine (120 or 150 mg kg-1) from gestation day (GD) 1 to 20. Both doses of caffeine resulted in maternal hyperthyroidism, whereas the elevation in the concentration of serum free triiodothyronine (FT3) and free thyroxine (FT4) was related to a depletion in the level of TSH at GD 20. Maternal body weight gain and food consumption were markedly increased, while fetal body weight was significantly reduced. These alterations caused fetal hypothyroidism and several pathological lesions in the fetal thyroid gland including a vacuolar colloid, destructive degeneration, atrophy and hyperplasia at embryonic day (ED) 20. The abnormalities in the fetal thyroid gland seemed to depend on the activation of caspase-3, Bcl-2, BAX, Cox2, and NF-κB mRNA expression. Both maternal caffeine doses caused a marked attenuation in the values of fetal serum GH, IGF-II, VEGF, TGF-β, TNF-α, IL-1β, IL-6, leptin and MCP-1, and a noticeable elevation in the value of fetal serum adiponectin at ED 20. Thus, gestational caffeine exposure might disrupt the fetal thyroid-cytokine axis.

Dietary soy isoflavones during pregnancy suppressed the immune function in male offspring albino rats

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Less attention has been paid to the immune effects of phytoestrogens during pregnancy on the first generation.

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Soy isoflavones fed to pregnant rats could modulate the immune response of the male offspring.

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Isoflavones reduced spleen and thymus weights in rats born to dams fed dietary soy.

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Soy isoflavones possibly mediated its effect through reduction of IFN-γ that interacts with the IL-12 production pathway.

Phytoestrogens have an impact on both animals and humans due to use of legumes in animal diets as well as the increase of vegetarian diets in some human populations. Phytoestrogens thought to have varieties of adverse effects, among which immune system was involved. The present study aimed to investigate the effect of prenatal exposure to dietary soy isoflavones on some immunological parameters in male albino rat offspring. The pregnant rats were divided to three groups (12/group). Control group (free soy isoflavones), low soy isoflavones group (6.5%) and high soy isoflavones group (26%). The male offspring cell-mediated immune response was determined using phytohemagglutinin (PHA) injection and the intumesce index which was calculated on postnatal day 50 (PND 50). At PND 50, blood samples were collected for interleukin 12 (IL-12), interferon γ (IFN-γ) and tumor necrosis factor α (TNF-α) determination. Spleen, thymus, and PHA injected footpads were fixed for histopathology. Intumesce index, IL-12, IFN-γ, spleen and thymus relative weights were significantly (P < 0.05) decreased in offspring born to dams fed low and high dietary soy isoflavones. In contrary, TNF-α was significantly (P < 0.05) increased in offspring born to dams fed high dietary soy isoflavones. Spleen of rats born to dams fed high dose of dietary soy isoflavones showed coagulative necrosis in white pulp. In conclusion, male offspring born to dams fed different levels of soy isoflavones showed marked immunosuppression after PHA stimulation. This effect was mediated through the reduced IFN-γ that interacts with the IL-12 production pathway.

Prenatal Exposure to Soy Isoflavones Altered the Immunological Parameters in Female Rats

Information on the effects of phytoestrogens on animals has increased recently; however, there were only few studies on prenatal exposure on cellular immune response. Pregnant rats were assigned to 3 groups (12 rats per group), the first was fed control diet, the second was fed low-dose (6.5 g/100 g of diet) soy isoflavones, while the third was fed high-dose (26 g/100 g of diet) soy isoflavones. The female offspring cell-mediated immune response was determined using phytohemagglutinin (PHA) injection, and intumesce index was calculated on postnatal day 50. After 24 hours of PHA injection, blood samples were collected for tumor necrosis factor α, interferon γ (IFN-γ), and interleukin (IL)-12 determination. Spleen, thymus, and PHA-injected footpads were fixed for histopathology. Intumesce index was significantly (P < 0.05) reduced in rats' offspring born from dams fed low- and high-dietary soy isoflavones than that in control groups. Thymic relative weights in offspring of rats fed high-dietary soy isoflavones showed a significant (P < 0.05) decrease compared to that in the control group. Female offspring where low and high-dietary soy isoflavones were fed to their dams showed a significant (P < 0.05) decrease in IFN-γ and IL-12 than that in control ones. Spleen of rats born from dams fed high dose of dietary soy isoflavones showed lymphocytic depletion in white pulp. Taking together, it is clear that dietary soy isoflavones at prenatal period had immunosuppressive effect on female offspring after PHA stimulation. This effect was mediated through reduced IFN-γ that interplayed in IL-12 production pathway thus reducing its level.

Mating decreases plasma levels of TGFβ1 and regulates myosalpinx expression of TGFβ1/TGFBR3 in the rat

Mating shuts down a 2-methoxyestradiol (2ME)-dependent, non-genomic activity that is responsible for accelerating egg transport in the rat oviduct. The aims of this work were to investigate the role of TGFβ1 in this 2ME-reduced activity and to determine the effect of mating on the expression and distribution of TGFβ1 and its receptor TGFBR3 in the rat oviduct. We determined the level of TGFβ1 in the plasma and oviductal fluid at 1, 3, or 6 hr during Day 1 of the oestrous cycle in unmated or mated animals. We then examined if 2ME accelerates oviductal egg transport in unmated rats that were previously treated with a neutralizing TGFβ1 antibody. The expression of Tgfb1 and Tgfbr3 mRNA and the level and distribution of TGFBR3 protein in the oviduct were also determined at these time points. Mating decreased TGFβ1 in the plasma, but not in the oviductal fluid, whereas antibody neutralization of circulating TGFβ1 did not prevent the effect of 2ME on egg transport. Mating decreased Tgfb1 and hastened the increase in TGFBR3 abundance in the myosalpinx. These results indicate that mating decreased circulating levels of TGFβ1 without shutting down the non-genomic 2ME response that normally accelerates egg transport. Levels of Tgfb1 transcript and TGFBR3 protein, however, changed in the myosalpinx of mated rats, suggesting a role for mating-associated factors in the autocrine and paracrine effects of TGFβ in the oviduct.

Prevention of tobacco carcinogen-induced lung cancer in female mice using antiestrogens

Increasing evidence shows that estrogens are involved in lung cancer proliferation and progression, and most human lung tumors express estrogen receptor β (ERβ) as well as aromatase. To determine if the aromatase inhibitor anastrozole prevents development of lung tumors induced by a tobacco carcinogen, alone or in combination with the ER antagonist fulvestrant, ovariectomized female mice received treatments with the tobacco carcinogen 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone (NNK) along with daily supplements of androstenedione, the substrate for aromatase. Placebo, anastrozole and/or fulvestrant were administered in both an initiation and a promotion protocol of lung tumorigenesis. The combination of fulvestrant and anastrozole given during NNK exposure resulted in significantly fewer NNK-induced lung tumors (mean = 0.5) compared with placebo (mean = 4.6, P < 0.001), fulvestrant alone (mean = 3.4, P < 0.001) or anastrozole alone (mean = 2.8, P = 0.002). A significantly lower Ki67 cell proliferation index was also observed compared with single agent and control treatment groups. Beginning antiestrogen treatment after NNK exposure, when preneoplastic lesions had already formed, also yielded maximum antitumor effects with the combination. Aromatase expression was found mainly in macrophages infiltrating preneoplastic and tumorous areas of the lungs, whereas ERβ was found in both macrophages and tumor cells. Antiestrogens, especially in combination, effectively inhibited tobacco carcinogen-induced murine lung tumorigenesis and may have application for lung cancer prevention. An important source of estrogen synthesis may be inflammatory cells that infiltrate the lungs in response to carcinogens, beginning early in the carcinogenesis process. ERβ expressed by inflammatory and neoplastic epithelial cells in the lung may signal in response to local estrogen production.