Placental cadmium as an additional noninvasive bioindicator of active maternal tobacco smoking.

Tobacco smoke (TS) is a mixture of chemicals that is known to exert carcinogenic and endocrine-disrupting effects, as well as adverse effects on various systems. In TS nicotine is the major alkaloid and cadmium (Cd) the most abundant metal ion. The aim of this investigation was to assess exposure to Cd attributed to TS in healthy postpartum subjects (mean age 28 years) after term vaginal delivery in a clinical hospital by determining metal levels in maternal blood, placenta, and cord blood in relation to nicotine in maternal hair (12-cm-long samples). Two study groups were compared based upon self-reporting data: smokers (n = 32; continual cigarette smoking 3 months before and 9 months during pregnancy) and nonsmokers (n = 54; including passive smokers whose parameters did not differ from unexposed nonsmokers). In smokers compared to nonsmokers maternal hair nicotine concentrations increased approximately sevenfold, while Cd levels rose fourfold in maternal blood and up to twofold in placenta. Significant positive correlations were noted between maternal hair nicotine and placental Cd, maternal hair nicotine and maternal blood Cd, and placental Cd and maternal blood Cd. Levels of cord blood Cd were low in both study groups (<0.1 ng/ml). Data indicate that Cd in placenta may serve as a noninvasive bioindicator in addition to commonly used noninvasive hair nicotine in maternal TS assessment, especially in cases where unavailable or inappropriate (short or chemically treated) hair samples occur.

Oral cadmium exposure during rat pregnancy: assessment of transplacental micronutrient transport and steroidogenesis at term.

Diet is the main source of cadmium (Cd) exposure. Gastrointestinal absorption increases during pregnancy. Cadmium accumulated in the placenta may interfere with nutrient transport to the foetus. Data on the potential of Cd to act as a steroid disruptor of pregnancy are limited. We evaluated the effects of oral Cd exposure during pregnancy on placental function in micronutrient transfer to the foetus and steroidogenesis in Wistar rats (regular 4-day cyclers) that mated with unexposed males. Pregnant rats were randomly assigned to a Cd group exposed orally to 50 mg Cd l(-1) (CdCl(2)xH2O dissolved in demineralized water), ≈ 7.5 mg Cd kg(-1) a day, during 20 days of gestation and control (supplied with demineralized water). Non-pregnant rats were treated under the same experimental conditions. On day 20, all of the rats were killed and samples were taken for element analyses (by electrothermal atomic absorption spectrometry). Progesterone and testosterone were measured in serum and placenta-derived samples (by immunoenzymometric assay and/or enzyme-linked immunosorbent assay). In the exposed rats, Cd increased in blood and organs, more in pregnant rats, and in placenta and foetus whereas zinc increased in liver. Iron decreased in maternal organs and in foetus, whereas zinc decreased in maternal kidney and placenta. Liver copper was lower and kidney copper higher in all pregnant vs. non-pregnant rats. Steroids in serum and placenta did not change. In conclusion, oral Cd exposure during rat pregnancy does not affect progesterone and testosterone at term. Transplacental iron and zinc handover are disrupted, which may put at risk the maintenance of foetal nutrition and viability.

Effects of Maternal Cigarette Smoking on Trace Element Levels and Steroidogenesis in the Maternal-Placental-Fetal Unit.

This study evaluates the interaction of toxic elements cadmium (Cd) and lead (Pb) due to exposure from cigarette smoking, essential elements, and steroidogenesis in the maternal-placental-fetal unit. In a cohort of 155 healthy, postpartum women with vaginal term deliveries in clinical hospitals in Zagreb, Croatia, samples of maternal blood/serum and urine, placental tissue, and umbilical cord blood/serum were collected at childbirth. The biomarkers determined were concentrations of Cd, Pb, iron (Fe), zinc (Zn), copper (Cu), and selenium (Se), and steroid hormones progesterone and estradiol in maternal and umbilical cord blood and the placenta. Three study groups were designated based on self-reported data on cigarette smoking habits and confirmed by urine cotinine levels: never smokers (n = 71), former smokers (n = 48), and active smokers (n = 36). Metal(loid)s, steroid hormones, urine cotinine, and creatinine levels were analyzed by ICP-MS, ELISA, GC-MS, and spectrophotometry. Cigarette smoking during pregnancy was associated with increased Cd levels in maternal, placental, and fetal compartments, Pb in the placenta, and with decreased Fe in the placenta. In active smokers, decreased progesterone and estradiol concentrations in cord blood serum were found, while sex steroid hormones did not change in either maternal serum or placenta. This study provides further evidence regarding toxic and essential metal(loid) interactions during prenatal life, and new data on sex steroid disruption in cord serum related to cigarette smoking. The results indicate that umbilical cord sex steroid levels may be a putative early marker of developmental origins of the future burden of disease related to harmful prenatal exposure to cigarette smoke.

Successful pregnancy and delivery after kidney transplantation.

The kidney transplantation is considered to be the best therapy for terminal kidney disease, nowadays. Numerous studies have shown that pregnancy may be successful and may result in a delivery of a healthy baby after the kidney transplantation. Pregnant women who are the recipients of a kidney transplant have increased chances of developing hypertension, preeclampsia, as well as going into premature labour and frequently giving birth to newborns of low birth weight. We present a case of a successful pregnancy and delivery in a 32-year-old kidney transplant recipient who conceived spontaneously four years posttransplantation. The kidney transplantation has been done due to the chronic hypertension and the consequential kidney atrophy. During the pregnancy, the patient underwent antihypertension and immunosupressive drugs therapy. She was also being monitored by the gynaecologist and the nephrologist. The pregnancy was terminated in the 40th week by an urgent Caesarean section due to the fetal bradycardia. The patient gave birth to the healthy baby girl.

The effects of maternal cigarette smoking on cadmium and lead levels, miRNA expression and biochemical parameters across the feto-placental unit.

Several miRNAs have been previously identified to be associated with cigarette smoke and/or the toxic metals cadmium (Cd) and lead (Pb). The aim of this study was to investigate the associations of maternal cigarette smoking with cadmium (Cd) and lead (Pb) levels, candidate miRNA expression and biochemical parameters across the feto-placental unit. miRNAs were isolated according to protocols provided by manufacturer from 72 healthy postpartum women using Qiagens' kits based on phenol/guanidine samples lysis and silica-membrane purification of total RNA. Candidate miRNAs (miR-1537, miR-190b, miR-16, miR-21, and miR-146a) were quantified by real-time PCR. Biochemical parameters were analyzed in plasma samples by standardized and harmonized enzymatic methods using appropriate calibrators, while CRP was determined by immunoturbidimetric method. Concentration of Cd and Pb in whole blood and placenta samples were measured by inductively coupled plasma mass spectroscopy. Cd levels in smokers were higher in all of the analyzed compartments of the feto-placental unit, Pb in maternal blood and placenta than non-smokers. Smokers also had a higher expression of miR-16 in maternal and miR-146a in cord plasma, and lower expression of miR-21 in the placenta in comparison to non-smokers. Urate concentrations in the maternal plasma of smokers were lower than this value in non-smokers. The study has demonstrated that maternal smoking was associated with toxic metals (Cd and Pb) levels, urate concentration and alteration of miRNA expression. Given that the effects of maternal smoking on miRNA expression are inadequate, all compartments of the feto-placental unit should be analyzed to obtain a complete picture. This paper is the first to report on the results of expression of cellular and circulating miRNAs simultaneously in maternal and fetal compartments and in the placenta.

Pre-amplification as a method for improvement of quantitative RT-PCR analysis of circulating miRNAs.

INTRODUCTION: The assessment of circulating miRNAs is challenging and still limited due to their low concentrations, small size and lack of reference values in human biological samples. Pre-amplification of complementary DNAs may facilitate reliable miRNA quantification. The aim of our study was to evaluate the efficacy of pre-amplification as a step to increase the sensitivity of qPCR analysis for five candidate circulating miRNAs presumably related to toxic metals and cigarette smoke exposure: miR-1537, miR-190b, miR-16, miR-21, and miR-146a. MATERIALS AND METHODS: Candidate miRNAs expression was analysed in plasma samples of 19 mother-newborn pairs. For isolation, transcription, pre-amplification and qPCR quantification kits and protocols by Qiagen (Hilden, Germany) were used. Paired t-test or Wilcoxon rank test were used to compare miRNAs expression levels with and without a pre-amplification step prior to qPCR, separately in maternal and cord plasma. Intraclass correlation (ICC) was calculated as an agreement measure between procedures for each miRNA. RESULTS: Pre-amplification facilitated the detection of all assayed miRNAs with an overall cycle threshold (CT) improvement of 6.6 ± 0.89 (P < 0.05). Excellent ICCs (> 0.90) were found between data for preamplified and not preamplified miR-16, miR-21 and miR-146a. However, these correlations for low expressed miR-190b were moderate (0.79 in maternal; 0.61 in cord plasma) and poor for miR-1537 (0.49 in maternal; no correlation in cord plasma). CONCLUSION: Pre-amplification is a useful, necessary step in the analysis of miR-1537 and miR-190b as a reliable procedure facilitating extracellular miRNA expression detection in human plasma by real-time PCR quantification.

Metals in human placenta: focus on the effects of cadmium on steroid hormones and leptin.

Cadmium and other metallic ions can act as metalloestrogens and endocrine disruptors of reproductive tissues and fetal development in mammals, including humans. The detrimental effects occur with respect to the synthesis of both steroid and polypeptide hormones in the placenta. Leptin is produced by the trophoblast and may regulate fetal organogenesis and development. In human term placentas, concentrations of toxic metals and their effects on steroidogenesis were assessed in healthy parturients (109 non-smokers and 99 smokers) in relation to tobacco smoking. Trace elements (cadmium, lead, iron, zinc and copper) were analyzed in placentas using atomic absorption spectroscopy, and steroid hormones (progesterone and estradiol) were assayed in placental samples by an enzyme-immunometric method. Cadmium concentrations were doubled in placentas of smokers as compared with non-smokers, and placental lead and zinc concentrations increased significantly. Placental concentrations of iron, copper, progesterone and estradiol did not differ. In addition, human trophoblast cells were co-cultured with 0, 5, 10 or 20 microm CdCl(2) for 96 h and leptin mRNA assessed by quantitative polymerase chain reaction. Leptin mRNA declined dose-responsively as a result of CdCl(2) exposure. Collectively, the results confirm that human placental tissue offers a unique opportunity to biomonitor cadmium exposure in both the maternal and the internal fetal environments. In addition, the results strongly suggest that cadmium may cause a decline in placental leptin synthesis, as we have previously shown for placental progesterone production. This may constitute further evidence of the endocrine-disrupting effects of cadmium, as a constituent of tobacco smoke, on reproduction in women.

Mercury Exposure Assessment in Mother-Infant Pairs from Continental and Coastal Croatia.

The main source of mercury (Hg) exposure in the general population is fish. Another possible source is dental amalgam. Here, we compare the levels of Hg and selenium (Se) in samples of maternal and fetal origin collected shortly after childbirth of healthy postpartum women in the coastal (n = 96) and continental (n = 185) areas of Croatia related to maternal seafood/fish consumption. We also evaluated Hg concentrations and maternal serum metallothionein (MT2) concentrations in relation to the number of dental amalgam fillings, and MT2A-5A/G (rs28366003) polymorphism. The levels of Hg and Se in maternal hair and blood/serum, placenta and cord blood/serum increased in relation to increasing fish consumption with the highest values in subjects from the coast. The concentrations of each element and between elements correlated across the matrices. Increasing amalgam number correlated linearly with increased Hg levels in maternal and cord serum and was not associated with serum MT2. No association of MT2A-5A/G polymorphism and Hg or Se levels were found. The results confirmed higher fish consumption in coastal vs. continental Croatia and increases of both Hg and Se related to fish consumption in all analyzed samples. Increased blood Hg reflected the predominant MeHg share from seafood, while increased serum Hg matched exposure from dental amalgams.

Cigarette Smoking during Pregnancy: Effects on Antioxidant Enzymes, Metallothionein and Trace Elements in Mother-Newborn Pairs.

The effect of maternal smoking as a source of exposure to toxic metals Cd and Pb on superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity, metallothionein (MT), Cd, Pb, Cu, Fe, Mn, Se and Zn concentrations were assessed in maternal and umbilical cord blood and placenta in 74 healthy mother-newborn pairs after term delivery. Sparse discriminant analysis (SDA) was used to identify elements with the strongest impact on the SOD, GPx and MT in the measured compartments, which was then quantified by multiple regression analysis. SOD activity was lower in maternal and cord plasma, and higher in the placenta of smokers compared to non-smokers, whereas GPx activity and MT concentration did not differ between the groups. Although active smoking during pregnancy contributed to higher maternal Cd and Pb concentrations, its contribution to the variability of SOD, GPx or MT after control for other elements identified by SDA was not significant. However, an impaired balance in the antioxidant defence observed in the conditions of relatively low-to-moderate exposure levels to Cd and Pb could contribute to an increased susceptibility of offspring to oxidative stress and risk of disease development later in life. Further study on a larger number of subjects will help to better understand complex interactions between exposure to toxic elements and oxidative stress related to maternal cigarette smoking.

Nonobstetrical Acute Abdomen during Pregnancy as a Consequence of Colorectal Carcinoma Perforation: Case Report and Review of the Literature.

Colorectal carcinoma is a rare but potentially fatal disease complicating pregnancy. It occurs most frequently in patients aged 50, although some studies report increasing incidence in women under the age of 40. Diagnosis of colorectal cancer during pregnancy is usually made at an advanced stage due to unspecific symptoms. We will present a case of an acute abdomen during pregnancy due to colorectal carcinoma perforation in a 33-year-old patient in her 26th week of gestation. Because of her abdominal condition, left hemicolectomy with colostomy was performed. Two hours after surgery, the patient gave birth to a male child weighing 910 g with an Apgar score of 2/6. The pathohistological finding indicated adenocarcinoma of the colon in Dukes stage B.

Metallothionein 2A gene polymorphism and trace elements in mother-newborn pairs in the Croatian population.

The main source of exposure for all essential and toxic elements in the general population is diet. In smokers, the main route for cadmium (Cd) and lead (Pb) intake is the inhalation of tobacco smoke. Besides gender, age, nutrition, lifestyle, and physiological conditions such as pregnancy, specific genetic characteristics also influence individual element uptake. Metallothionein MT2 is a cysteine-rich low-weight protein found ubiquitously throughout the body. Specific gene polymorphism may influence MT2 expression and subsequent binding, transfer and organ accumulation of metals, though data on these influences are lacking, especially in human mother-newborn pairs. The objective of this study was to determine selected toxic (Cd, Pb, Hg) and essential (Fe, Zn, Cu, Se) elements in maternal blood, placenta, and cord blood (by ICP-MS), and MT2 levels in maternal serum (by ELISA) in relation to maternal MT2A -5A/G (rs28366003) polymorphism (by RFLP-PCR and electrophoresis). Study participants were healthy postpartum women in Croatia (n=268, mean age 29 years) with term vaginal childbirth in a maternity ward assigned into two study groups by self-reporting about their smoking habit (by questionnaire). Smokers vs. non-smokers had increased levels of Cd and Pb in all measured samples, Fe and Cu in cord blood, Zn in placenta, and MT2 in maternal serum. Among subjects with AG/GG genotype, placental Fe was significantly lower only among non-smokers, while MT2 levels in serum were lower, though not significantly, regardless of maternal smoking habit. There was no impact of MT2A -5A/G SNP on any element in maternal or cord blood. In conclusion, the results confirmed maternal smoking-related increases in Cd and Pb levels in the maternal-placental-foetal unit. They also provided additional data on concomitant metal concentrations in representative samples of maternal blood, placenta, and cord blood, as well as increased cord blood Fe and Cu, placental Zn, and maternal serum MT2 in smokers. New evidence is that MT2A -5A/G SNP was associated with decreased placental Fe levels in non-smokers. For a final conclusion on the influence of the MT2A -5A/G polymorphism on toxic and essential element levels in mother-newborn pairs, further research would require a larger number of participants divided across subgroups defined by the main source of particular toxic metal exposure (such as specific food intake, cigarette smoking, air pollution and/or occupational exposure).

Tobacco smoke and pregnancy: segmental analysis of nicotine in maternal hair.

The investigation assessed nicotine metabolism prior to and during pregnancy in relation to different maternal smoking habits. It included segmental hair analysis in 3 groups of postpartum women: 32 active smokers, 35 passive smokers, and 19 unexposed nonsmokers. Maternal hair at least 12 cm long was collected after delivery and was divided into four 3-cm-long segments representing each trimester of pregnancy and the 3 months prior to pregnancy. Hair nicotine concentration was determined by gas chromatography-mass spectrometry. Nicotine levels were the highest in the 3-month period before pregnancy and it gradually decreased with advancing gestation in all study groups. These results suggest that when assessing tobacco exposure as measured by nicotine in hair, metabolic changes of nicotine during pregnancy should be taken into consideration.

Wilson's disease in pregnancy.

Wilson's disease is a rare autosomal recessive disorder of copper metabolism. It causes cirrhosis of the liver, consequently followed by disorder of the menstrual cycle and infertility. Successful decopperizing may lead to restoration of the ovulatory cycle and enable pregnancy. Increased copper levels may cause preeclampsia, intrauterine growth restriction and neurologic damages in the fetus. Pregnant women with decompensated liver cirrhosis face more complications, including bleeding from esophageal varices, liver failure, encephalopathy, and rupture of the splenic artery. We present a case of Wilson's disease in a patient who had spontaneously conceived three times. The first pregnancy ended with delivery of a healthy baby at term. In second pregnancy, medically induced abortion was performed in the 12th week because of deterioration of the underlying disease, liver cirrhosis with portal hypertension. In the same year, the patient underwent liver transplantation. Two years after the transplantation, the patient spontaneously conceived and delivered vaginally a healthy child.