The effect of maternal exposure to dioxin on fetal steroidogenesis in the steroidogenic organs

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposed to pregnant or lactational mother impairs the reproduction and development of the pups. The defect is a serious problem, because it is caused by TCDD at much lower doses than that needed for acute toxicity in the mother. However, the toxic mechanism underlying the defect remains to be obscure. We have previously revealed that maternal exposure to TCDD (1 microg/kg) causes a reduction in luteinizing hormone in the fetal pituitary, leading to the reduced expression of testicular steroidogenic proteins such as steroidogenic acute-regulatory protein (StAR) and cytochrome P450 (CYP) 17. In addition, we have provided evidence that such a reduction imprints defects in sexual behaviors at adulthood. In this study, we investigated TCDD effect on fetal steroidogenesis in the extra-gonadal tissues. Even when pregnant Wistar rats at gestational day (GD) 15 were orally treated with TCDD (0.25, 1 or 3 microg/kg), neither expression of StAR nor CYP17 mRNA was affected in the adrenal gland, placenta and hypothalamus of male fetuses (GD20). However, TCDD induced placental StAR (3 microg/kg) and adrenal CYP17 mRNAs (0.25 microg/kg) in female fetuses. Therefore, our study suggests that while TCDD gives damage to male fetal steroidogenesis in a testis-specific manner, the dioxin enhances the steroidogenesis of the fetal adrenal gland and placenta in females. Thus, the mechanism whereby TCDD exerts its endocrine-disrupting properties is considered to differ, at least partially, between male and female fetuses.     

Down-regulation of placental transport of amino acids precedes the development of intrauterine growth restriction in rats fed a low protein diet

Intrauterine growth restriction (IUGR) represents an important risk factor for perinatal complications and for adult disease. IUGR is associated with a down-regulation of placental amino acid transporters; however, whether these changes are primary events directly contributing to IUGR or a secondary consequence is unknown. We investigated the time course of changes in placental and fetal growth, placental nutrient transport in vivo and the expression of placental nutrient transporters in pregnant rats subjected to protein malnutrition, a model for IUGR. Pregnant rats were given either a low protein (LP) diet ( n = 64) or an isocaloric control diet ( n = 66) throughout pregnancy. Maternal insulin, leptin and IGF-I levels decreased, whereas maternal amino acid concentrations increased moderately in response to the LP diet. Fetal and placental weights in the LP group were unaltered compared to control diet at gestational day (GD) 15, 18 and 19 but significantly reduced at GD 21. Placental system A transport activity was reduced at GD 19 and 21 in response to a low protein diet. Placental protein expression of SNAT2 was decreased at GD 21. In conclusion, placental amino acid transport is down-regulated prior to the development of IUGR, suggesting that these placental transport changes are a cause, rather than a consequence, of IUGR. Reduced maternal levels of insulin, leptin and IGF-1 may link maternal protein malnutrition to reduced fetal growth by down-regulation of key placental amino acid transporters.     

何首乌饮对运动疲劳大鼠睾丸组织P450胆固醇侧链裂解酶和类固醇激素急性调节蛋白的影响

目的 探讨何首乌饮对运动疲劳大鼠睾丸组织细胞色素P450胆固醇侧链裂解酶(P450scc)和类固醇激素急性调节蛋白(StAR)的影响.方法 60只雄性SD大鼠,随机分为安静对照组(A组)、安静何首乌饮组(B组)、模型组(C组)、自然恢复组(D组)、何首乌饮治疗组(E组);何首乌饮预防组(F组),每组10只.C、D、E和F组大鼠复制运动疲劳动物模型,其中F组每天训练前给何首乌饮20g/(kg·d)(含生药4.8kg/L)灌胃60 d.模型成功后E组给何首乌饮20 g/(kg·d)(含生药4.8kg/L)灌胃治疗60 d.采用美国Beckmancoulter Unicel Dxl 800仪器测定睾酮水平; 采用RT-PCR、Western blotting和免疫组织化学法检测各组睾酮合成限速酶P450scc和StAR的表达变化.结果 P450scc免疫组织化学阳性颗粒主要表达于间质细胞及精母细胞,B组和F组表达最强,C组最弱,与其余各组相比差异有统计学意义.P450scc蛋白和mRNA表达变化为B、F组明显高于E、D和A组(P<0.05),C组明显低于A组(P<0.05),A组和D组以及B组和F组两两之间差异无显著性;StAR免疫组织化学阳性颗粒主要表达于睾丸间质细胞胞质,阳性强度表现为E组和F组最强,C组最弱.StAR蛋白和mRNA表达变化为E和F组明显高于A、D组(P<0.05),C组明显低于A组(P<0.05),A、D组之间无差异.结论 何首乌饮可以提高睾酮合成限速酶P450scc和StAR的表达.     

何首乌饮对大鼠睾丸间质细胞类固醇激素合成急性调节蛋白和细胞色素P450胆固醇侧链裂解酶蛋白表达的影响

目的探究何首乌饮影响大鼠睾丸间质(Leydig)细胞类固醇激素合成急性调节蛋白(St AR)和细胞色素P450胆固醇侧链裂解酶(P450scc)蛋白表达的变化。方法选用10~20 d的幼年雄性Wistar大鼠,分离、培养Leydig细胞,然后收集。采用氧化损伤的方法建立Leydig细胞衰老模型。实验分组:间质细胞衰老模型组,何首乌饮处理组,首乌丸处理组,正常组和何首乌饮对照组。结果衰老模型组Leydig细胞St AR和P450scc的免疫组织化学染色强度明显低于正常组和何首乌饮对照组(P0.01)。另一方面,何首乌饮和何首乌丸干预组St AR和P450scc的免疫组织化学染色强度明显高于衰老模型组(P0.05),何首乌饮组好于何首乌丸组。结论何首乌饮可提高睾丸Leydig细胞St AR和P450scc蛋白的表达,提高睾酮的合成能力,从而延缓Leydig细胞衰老。     

Fetal exposure to excess glucocorticoid is unlikely to explain the effects of periconceptional undernutrition in sheep

Periconceptional undernutrition alters fetal growth, metabolism and endocrinology in late gestation. The underlying mechanisms remain uncertain, but fetal exposure to excess maternal glucocorticoids has been hypothesized. We investigated the effects of periconceptional undernutrition on maternal hypothalamic–pituitary–adrenal axis function and placental 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) activity. Ewes received maintenance feed (N, n = 20) or decreased feed from −60 to +30 days from mating to achieve 15% weight loss after an initial 2-day fast (UN, n = 21). Baseline plasma samples and arginine vasopressin (AVP)–corticotrophin-releasing hormone (CRH) challenges were performed on days −61, −57, −29, −1, +29, 33, and 49 from mating (day 0). Maternal adrenal and placental tissue was collected at 50 days. Baseline plasma levels of adrenocorticotrophic hormone (ACTH) and cortisol decreased in the UN group ( P < 0.0001). ACTH response to AVP–CRH was greater in UN ewes during undernutrition ( P = 0.03) returning to normal levels after refeeding. Cortisol response to AVP–CRH was greater in UN ewes after the initial 2-day fast, but thereafter decreased and was lower in UN ewes from mating until the end of the experiment ( P = 0.007). ACTH receptor, StAR and p450c17 mRNA levels were down-regulated in adrenal tissue from UN ewes. Placental 11βHSD2 activity was lower in UN than N ewes at 50 days ( P = 0.014). Moderate periconceptional undernutrition results in decreased maternal plasma cortisol concentrations during undernutrition and after refeeding, and adrenal resistance to ACTH for at least 20 days after refeeding. Fetal exposure to excess maternal cortisol is unlikely during the period of undernutrition, but could occur later in gestation if maternal plasma cortisol levels return to normal while placental 11βHSD2 activity remains low.     

姜黄素衍生物B06对2型糖尿病大鼠睾酮合成的影响

 目的: 研究姜黄素衍生物B06对2型糖尿病大鼠睾酮合成的影响。方法: 雄性SD大鼠35只,随机均分为正常对照组(C组)、高脂组(H组)、高脂治疗组(HT组)、糖尿病组(D组)和糖尿病治疗组(DT组),后4组高脂喂养4周后,D组及DT组用低剂量链脲佐菌素诱导糖尿病,HT组和DT组用0.2 mg·kg^-1·d^-1的B06灌胃8周。微量血糖仪测定大鼠血糖浓度;ELISA法测定血胰岛素水平,并计算胰岛素抵抗指数;光镜和电镜观察睾丸形态;放射免疫法测定血睾酮、雌二醇水平;免疫组化检测Leydig细胞的类固醇激素合成急性调节蛋白(StAR)表达;RT-PCR检测睾丸Leydig细胞StAR、胆固醇侧链裂解酶(P450scc)、细胞色素P450 17A1(P450c17)、细胞色素P450芳香化酶(P450arom)、3β-羟基类固醇脱氢酶(HSD)及17β-HSD的mRNA表达水平。结果: H组及D组血糖、胰岛素抵抗指数升高,血清睾酮水平降低,经B06治疗后好转;H组及D组睾丸曲细精管变形,生精细胞脱落,Leydig细胞内线粒体肿胀,内质网减少且扩张,胞核皱缩,染色质稀疏,经B06治疗后病变减轻;D组的StAR蛋白表达减弱,经B06治疗后表达增强;H组及D组Leydig细胞StAR、P450scc mRNA表达降低,经B06治疗后升高,P450c17、P450arom、3β-HSD及17β-HSD mRNA表达未见明显差异。结论: B06可缓解2型糖尿病大鼠睾丸病变,提高血清睾酮水平,这可能与B06改善机体代谢紊乱并上调Leydig细胞StAR及P450scc mRNA表达水平相关。     

LXR激活对大鼠原代培养海马神经元胆固醇代谢关键酶基因表达的影响

为了探讨肝X受体(LXR)激活对海马神经元胆固醇代谢关键酶基因表达和胆固醇外流的影响,本研究取当天新生大鼠海马神经元行体外培养7d,随机分为TO组(培养液含2.0μmol/L的TO901317)和正常对照组(CON),继续培养48h。用胆固醇氧化酶-比色法检测TO组胆固醇的排出量;应用RT-PCR方法检测两组海马神经元ATP结合盒转运体A1(ABCA1)、HMG-CoA还原酶(HMGR)、胆固醇24-羟化酶(CYP46)、P450侧链裂解酶(P450scc)、固醇生成急性调节蛋白(StAR)和酰基辅酶A-胆固醇酰基转移酶1(ACAT1)等胆固醇代谢关键酶基因的mRNA的表达。结果显示:TO组mRNA表达上调的酶有HMGR、P450scc和StAR(P<0.01);表达下调的酶是ACAT1(P<0.01);表达不受影响的酶是CYP46。上述结果表明LXR激活、促进细胞内胆固醇外流时,海马神经元可能通过协调胆固醇代谢关键酶基因的表达,增加胆固醇的合成和向神经甾体的转化,抑制胆固醇的储备,而不影响胆固醇排出血脑屏障,从而维持细胞内胆固醇的动态平衡,保证神经元的正常生理功能。     

Prenatal nicotine exposure transiently alters the lung mechanical response to hypoxia in young lambs

To test the hypothesis that fetal nicotine exposure alters the lung mechanical response to hypoxia (10% O(2)) 10 lambs were exposed during the last fetal trimester to a low dose nicotine (LN) and 10 to a moderate dose (MN) (maternal dose 0.5 and 1.5mg/(kgday) free base, respectively). There were 10 controls (C). At 12 days, minute ventilation increased significantly less in MN compared with LN but not with C. In contrast to C and LN, MN did not show anticipated increases in dynamic compliance, specific compliance and FRC or decrease in lung resistance but had signs of airway hyperreactivity during hypoxia. Nicotine exposure did not alter the cardiovascular response. These adverse effects decreased with advancing age. In summary, prenatal nicotine exposure alters the lung mechanical response to hypoxia. We speculate that prenatal nicotine-induced alterations of lung mechanics during hypoxia may contribute to an increased vulnerability to hypoxic stress during infancy.     

Foetal exposure to Panax ginseng extract reverts the effects of prenatal dexamethasone in the synthesis of testosterone by Leydig cells of the adult rat

The aim of this study was to examine the effect of maternal exposure to Panax ginseng extract (GE) on the prenatal dexamethasone (DEXA)‐induced increase in testosterone production by isolated Leydig cells in adult rats. Pregnant rats were treated with (i) GE (200 mg/kg) or vehicle on days 10–21; (ii) DEXA (100 μg/kg) or vehicle on days 14–21; or (iii) a combination of GE plus DEXA at the same doses and with the same regimen. Testosterone production was induced either by the activator of protein kinase A (dbcAMP) or substrates of steroidogenesis [22(R)‐hydroxycholesterol (22(R)‐OH‐C)] and pregnenolone. The capacity of rat Leydig cells exposed to DEXA to synthesize testosterone induced by dbcAMP, 22(R)‐OH‐C or pregnenolone was increased in comparison with the control group. Combined exposure to DEXA + GE prevented the effect of DEXA on the responsiveness of Leydig cells to all inductors of testosterone synthesis, whereas GE alone did not modify the response to inductors. No modifications in testosterone production were observed under basal conditions. StAR immunoexpression in Leydig cells was not modified by prenatal exposure to DEXA, GE or DEXA + GE. P450scc and glucocorticoid receptor immunoexpression was higher in offspring exposed to DEXA in comparison with the control group. This increased expression was prevented by combined treatment with DEXA + GE. The present findings demonstrate that GE is capable of reversing the effect of DEXA on testosterone synthesis by rat Leydig cells.     

Interplay between estrogen-related receptors and steroidogenesis-controlling molecules in adrenals. In vivo and in vitro study

Estrogen-related receptors (ERRs) α, β and γ appear to be novel molecules implicated in estrogen signaling. We blocked and activated ERRs in mouse (C57BL/6) adrenals and adrenocortical cells (H295R) using pharmacological agents XCT 790 (ERRα antagonist) and DY131 (ERRβ/γ agonist), respectively. Mice were injected with XCT 790 or DY131 (5?μg/kg bw) while cells were exposed to XCT 790 or DY131 (0.5?μg/L). Irrespectively of the agent used, changes in adrenocortical cell morphology along with changes in lutropin, cholesterol levels and estrogen production were found. Diverse and complex ERRs regulation of multilevel-acting steroidogenic proteins (perilipin; PLIN, cytochrome P450 side-chain cleavage; P450scc, translocator protein; TSPO, steroidogenic acute regulatory protein; StAR, hormone sensitive lipase; HSL and HMG-CoA reductase; HMGCR) was revealed. Blockage of ERRα decreased P450scc, StAR and TSPO expressions. Activation of ERRβ/γ increased P450scc, StAR and HMGCR while decreased HSL expressions. PLIN expression increased either after XCT 790 or DY131 treatment. Additionally, treatment with both XCT 790 or DY131 decreased activity of Ras/Raf, Erk and Akt indicating their involvement in control of morphology and steroidogenic function of cortex cells. ERRs are important in maintaining morpho-function of cortex cells through action in specific, opposite, or common manner on steroidogenic molecules.     

不同剂量60Co-γ射线对TM3细胞的损伤效应

目的：对不同剂量60Co-γ射线下TM3细胞的损伤进行细胞生物学行为、转录层面的分析。方法：TM3细胞分4组,包括3个60Co-γ射线照射组(3、6、9 Gy)及对照组(不照射)。于24、48、72 h观察各组细胞凋亡情况(流式细胞法)、氧化损伤(ELISA)、睾酮合成关键因子(StAR、P450scc、P450c17及3β-HSD)的mRNA表达(实时定量PCR法)。于24、48、72、96、120、144 h,观察细胞增殖情况(MTS法)。结果：第24、72 h,各照射组细胞凋亡率均高于对照组(P<0.008);MTS实验中,第144、120 h,各照射组OD490值均低于对照组(P<0.008);第24,48,72 h,3 Gy组8-OHdG浓度与对照组相比无差异(P>0.008),而9 Gy组高于对照组(P<0.008);在72 h,各照射组StAR、P450scc、3β-HSD mRNA表达均低于对照组(P<0.008),而P450c17的表达在3 Gy组中无显著改变,在6 Gy组中高于对照组,在9 Gy组中低于对照组。结论：60Co-γ射线使TM3细胞凋亡增加、细胞增殖能力下降。6 Gy、9 Gy照射可以导致TM3细胞DNA的氧化损伤。辐照导致TM3细胞中StAR、P450scc、3β-HSD mRNA表达下降。6 Gy的照射使P450c17 mRNA表达上升,9 Gy使之下降。     

双岐杆菌减轻盐酸环丙沙星所致的小鼠血清睾酮下降

目的探讨双岐杆菌减轻盐酸环丙沙星所致小鼠血清睾酮下降。方法成年雄性昆明小鼠24只,随机分为灌胃0.9%Nacl溶液6 d(Sal6)组、灌胃抗生素6 d(A_6)组、灌胃抗生素6 d后灌胃0.9%Nacl溶液6 d(A_6+Sal_6)组和灌胃抗生素6 d后灌胃双岐杆菌6 d(A_6+P_6)组,每组6只。放免法检测血清睾酮含量;Western blot检测核转录相关因子2(Nrf2)、血红素氧化酶(HO-1)和4羟基壬烯醛(4-HNE)蛋白的表达;real-time PCR检测类固醇激素合成急性调控蛋白(St AR)、胆固醇侧链裂解酶(P450scc)和Nrf2 mRNA的表达;免疫组织化学检测4-HNE蛋白的表达。结果 A_6组血清睾酮水平明显低于Sal6组(P0.001),A_6+P_6明显高于A_6(P0.001)和A_6+Sal_6组(P0.01);睾酮合成酶也表现为同样的变化趋势,A_6组St AR mRNA明显低于Sal6组(P0.001),A_6+P_6组明显高于A_6组(P0.01)和A_6+Sal_6组(P0.01);P450scc mRNA明显低于Sal6组(P0.001),A_6+P_6组明显高于A_6组(P0.001)和A_6+Sal_6组(P0.05);A_6组Nrf2表达明显低于Sal6组(P0.01),A_6+P_6组明显高于A_6组(P0.01)和A_6+Sal_6组(P0.05);A_6组4-HNE的表达明显高于Sal6组(P0.001),A_6+P_6组明显低于A_6组(P0.01)和A_6+Sal_6组(P0.05)。结论双岐杆菌可能是通过调节Nrf2通路,上调抗氧化酶蛋白水平并下调氧化损伤产物,进而减轻盐酸环丙沙星所致小鼠血清睾酮水平下调作用的。     

Reduction of procarbazine-induced cleft palates by prenatal folic acid supplementation in rats

We investigated the effects of prenatal folic acid supplementation on procarbazine (PCZ)-induced intra-uterine growth retardation (IUGR), cleft palates, and microgenia. Three groups of gravid rats were treated with 200 mg/kg body weight (BW) PCZ on day 13.5 of gestation (GD13.5). Two groups of them were additionally supplemented with 1 and 2.5 mg/kg folic acid, respectively, from GD13.5 through GD16.5. On GD19.5, all fetuses were delivered by caesarian sections and sexed subsequently. Numbers of live and dead fetuses as well as resorptions were counted. Data on fetal BW, crown-rump length, tail length, placental weight, and diameter were collected. Fetal heads were histologically scrutinized for the occurrence of cleft palates and microgenia. Folic acid at 2.5 mg/kg diminished PCZ-induced IUGR. In male fetuses, both folic acid doses significantly reduced the incidence of cleft palates and microgenia, while in females, only the high folic acid dose was capable of lowering the occurrence frequency of cleft palates. We conclude that folic acid supplementation at the used doses confers a substantial protection against PCZ-induced IUGR and incidence of cleft palates and microgenia. However, these effects are gender-related and dose-dependent.     

健胎液对胎儿宫内发育迟缓孕鼠血浆、胎盘NO含量的影响

为从孕鼠血浆和胎盘一氧化氮（ＮＯ）水平探讨中药“健胎液”治疗胎儿宫内发育迟缓（ＩＵＧＲ）的机理，采用被动吸烟法建立ＩＵＧＲ动物模型，应用镀铜镉还原和内标比色法（Ｇｒｅｉｓ法），测定ＩＵＧＲ组、ＩＵＧＲ加健胎液组（用药组）孕鼠血浆及胎盘组织中ＮＯ的稳定代射终产物亚硝酸基／硝酸基（ＮＯ－２／ＮＯ－３）含量，并以正常孕鼠作对照。结果：与正常对照组和用药组相比，ＩＵＧＲ组胎鼠平均出生体重显著降低（Ｐ＜００１），ＩＵＧＲ组血浆及胎盘组织中ＮＯ－２／ＮＯ－３含量均显著降低（Ｐ＜００５～００１），而用药组和正常组相比，胎鼠平均出生体重、血浆及胎盘组织中ＮＯ－２／ＮＯ－３含量均无显著性差异（Ｐ＞００５）。结论：胎儿宫内发育迟缓的发生与ＮＯ的合成和释放显著降低，因而影响胎盘微循环，限制了母儿宫内发育迟缓。     

Igf2基因差异性甲基化区域在二(口恶)英致畸中的作用

目的研究2,3,7,8-四氯二苯并-对-二口恶英(2,3,7,8-tetrachlorodibenzo-p-dioxin,TCDD)对胎鼠生长发育的影响,探讨TCDD致畸与胰岛素样生长因子2(insulin-like growth factor2,Igf2)基因的表达和差异性甲基化区域(differentially methylated regions,DMRs)甲基化状态的关系。方法经灌胃给予孕10d大鼠10μg/kgTCDD,孕20天剖宫取胎,比较实验组和对照组孕鼠妊娠结局,测量两组活胎的顶臀长、体重和胎盘重;用实时定量-逆转录PCR检测孕20天胎鼠肝脏组织Igf2基因mRNA的表达;用蛋白印迹方法检测蛋白的表达水平;用甲基化限制酶HpaⅡ酶切-PCR法(HpaⅡ-PCR assay)检测两组胎鼠肝脏Igf2基因DMR1的甲基化程度,用亚硫酸氢盐测序方法检测Igf2基因DMR2的甲基化程度。结果对照组胎鼠均正常;实验组出现死胎及吸收胎,发生率为12.2%,畸形胎发生率为11.6%,活胎顶臀长、体重及胎盘重均明显低于对照组;对两组胎鼠肝脏组织Igf2基因表达的检测结果显示,实验组Igf2mRNA表达的相对量为0.77±0.11,对照组为0.27±0.15,两者差异有统计学意义(P<0.01);同时实验组肝脏组织Igf2蛋白的表达量也明显高于对照组;两组胎鼠肝脏Igf2基因DMR1的甲基化程度无差异,DMR2甲基化程度实验组明显低于对照组。结论孕期暴露于TCDD可导致大鼠发生死胎、吸收胎、畸形胎和胎儿宫内发育迟缓,TCDD所致胎鼠发育异常可能与胎鼠肝脏组织Igf2基因DMR2甲基化程度降低引起的Igf2高表达有关。     

The relationship between fetal growth restriction and small placenta in 6-mercaptopurine exposed rat

In order to investigate the effect of placental size on fetal intrauterine growth retardation (IURG), we examined the morphology and alterations in the expression of glucose transporter in the placentas of rats exposed to 6-mercaptopurine (6-MP). 6-MP was administered orally at 0 and 60 mg/kg/day on gestation day (GD) 9, 11, 13 or 15, and the placentas were sampled on GDs 17 and 21. The main findings in the treated groups were small placenta caused by mitotic inhibition and apoptosis, fetal resorption and IUGR with or without some malformations. The most sensitive period to 6-MP-induced fetal mortality was found to be in the GD9-treated group, and the small placenta and fetal abnormalities in the GD11-treated group, respectively. However, the litters in a quarter of the dams with the treatment on GD 11 had no fetotoxicity despite 25% decline in the placental weight. Histopathologically, the expression of glucose transporter GLUT3 was increased in the trophoblastic septa in all treated groups, particularly remarkable with proliferation of trophoblasts in the above litters, where the fetal–placental weight ratio was increased.Thus, we consider that the normal fetal growth and development can be maintained caused by adaptive change, even if the placental weight decreased by approximately 25% in 6-MP exposed rats.     

Effect of nicotine on placental ischemia-induced complement activation and hypertension in the rat

Preeclampsia is a pregnancy-specific condition manifested by new-onset maternal hypertension with systemic inflammation, including increased innate immune system complement activation. While exact pathophysiology is unknown, evidence suggests that inadequate spiral artery invasion and resulting utero-placental insufficiency is the initiating event. Cigarette smoking during pregnancy decreases the risk of preeclampsia. Nicotine, a major component of cigarettes, stimulates the efferent cholinergic anti-inflammatory pathway through peripherally expressed nicotinic acetylcholine receptors (nAChR) and is known to attenuate ischemia–reperfusion injury in kidney and liver. Prior studies indicated that complement activation was critical for placental ischemia-induced hypertension in a rat model. Thus, it was hypothesized here that nicotine was responsible for the protective effect of cigarette smoking in preeclampsia and would attenuate placental ischemia-induced systemic complement activation and hypertension. The Reduced Utero-placental Perfusion Pressure (RUPP) model in the pregnant rat was employed to induce placental ischemia, resulting in complement activation, fetal resorptions, and hypertension. On gestation day (GD)14, nicotine (1?mg/kg) or saline was administered via subcutaneous injection prior to RUPP surgery and daily through GD18. On GD19, placental ischemia significantly increased mean arterial pressure (MAP) in saline injected animals. However, the placental ischemia-induced increase in blood pressure was not evident in nicotine-treated animals and nicotine treatment significantly increased MAP variability. Circulating C3a was measured as an indicator of complement activation and increased C3a in RUPP compared to Sham persisted with nicotine treatment, as did fetal resorptions. These data suggested to us that nicotine may contribute to the decreased risk of preeclampsia with cigarette smoking, but this protective effect was confounded by additional effects of nicotine on the cardiovascular system.     

Prenatal smoking exposure and asymmetric fetal growth restriction

Background: Prenatal smoking exposure causes intrauterine fetal growth restriction (IUGR), although its effects on fetal proportionality are less clearly defined.

Aim: The present study assessed fetal proportionality in babies with IUGR using maternal salivary cotinine to indicate maternal smoking exposure.

Subjects and methods: A case-control study at the Liverpool Women's Hospital, UK of babies with asymmetric and symmetric IUGR and non-growth restricted babies was carried out.

Results: 270 white women including 90 IUGR cases and 180 controls were enrolled. Asymmetry presented in 52.2% of IUGR cases. Geometric mean maternal cotinine concentration was higher with asymmetric (p=0.002) than symmetric IUGR (p=0.07), when compared to controls. Maternal smoking exposure was independently associated with asymmetric IUGR (OR 2.4, 95% CI, 1.5–4.4, p≤0.001). Maternal anaemia was more frequent in babies with symmetric IUGR (OR 1.9, 1.3–3.4, p=0.002), but not in asymmetric babies. Rohrer's index ranged between 1.64 and 2.25 for asymmetric infants and significantly decreased with increasing maternal cotinine concentration in IUGR babies. Increased cotinine was not associated with shortened gestational age in IUGR babies.

Conclusions: Asymmetric IUGR occurred more frequently in heavy smokers. Stopping smoking even late in pregnancymay be beneficial for improved fetal outcomes. Symmetric IUGR was associated with maternal anaemia, highlighting the importance of prenatal nutritional status.     

Establishment of FSH-responsive cell lines by transfection of pre-ovulatory human granulosa cells with mutated p53 (p53val135) and Ha-ras genes.

Human granulosa cells were immortalized by transfection of the primary cells with a mutated p53 gene in combination with the Harvey-ras oncogene, yielding established cell lines designated HGP53. Here we report that forskolin, 8-Br-cAMP and FSH modulate cell growth and steroidogenesis in HGP53 cells. Low concentrations of 8-Br-cAMP or FSH stimulated cell proliferation, while higher doses attenuated cell proliferation. Progesterone production was already evident at an FSH concentration of 0.3 mIU/ml and was maximally stimulated (50-135-fold) at 50 mIU/ml of FSH. Expression levels of steroidogenic acute regulatory protein (StAR), adrenodoxin and cytochrome P450scc were enhanced 64-, 48- and 3.1-fold respectively by FSH stimulation. Dexamethasone enhanced FSH/cAMP-induced steroidogenesis and this effect involved a marked elevation in the intracellular level of adrenodoxin and P450scc, concomitantly with a marked decrease in StAR. Conversely, basic fibroblast growth factor attenuated FSH-stimulated progesterone production, and this effect involved reductions in adrenodoxin, P450scc and StAR levels. These data suggest that the rate of steroidogenesis may be determined by the ratio of StAR and P450scc, rather than by the level of each protein alone. Whereas FSH at a low dose slightly reduced apoptosis induced by serum withdrawal from HGP53 cells, higher doses enhanced it. Dexamethasone dramatically attenuated FSH- or forskolin-enhanced apoptosis. In conclusion, FSH-dependent mechanisms of differentiation, luteinization and apoptosis can be preserved in human granulosa cells immortalized by mutated p53. Moreover, this system lends itself to studies on cross-talk between the endocrine and paracrine factors that control these processes.