Newborns Of Non-smoking Mothers Research Articles

Gestational acrylamide exposure and biomarkers of fetal growth: Probing the mechanism underlying the association between acrylamide and reduced fetal growth

IntroductionFour epidemiological studies have shown a negative association between prenatal acrylamide exposure and birth size. In order to shed light on the possible underlying mechanism(s), we analysed associations between acrylamide biomarkers and biomarkers related to fetal growth. MethodsIn newborns of the ENVIRONAGE birth cohort (n ranges from 215 to 434), we investigated the association between prenatal acrylamide exposure (acrylamide and glycidamide hemoglobin adduct levels in cord blood) and thyroid hormones (TSH, T3, T4 and the ratio of T4 to T3 in cord plasma), insulin-related factors (cord plasma insulin and IGF1, and placental IGF2), neurotrophins (cord plasma BDNF, and placental NGF, NT3 and NT4), and cord plasma homocysteine and progesterone, using multiple linear regression analysis. In addition, we investigated whether the biomarkers mediated the associations between prenatal acrylamide exposure and birth outcomes. ResultsWe observed lower cord plasma TSH (−10.2% [95% CI: −15.0, −4.3]) and higher placental NGF levels (10.0% [95% CI 3.7, 17.4]) for a twofold increase of acrylamide adducts, a decrease in the ratio of cord plasma free T4 and free T3 with higher acrylamide and glycidamide adducts of −2.9% (95% CI: −5.7, −0.1) and −3.9% (95% CI: −6.2, −1.6) for a twofold increase in acrylamide and glycidamide adduct levels, respectively, and higher cord plasma free T3 with increases in both acrylamide and glycidamide adducts of 2.8% (95% CI: 0.2, 5.6) and 3.6% (95% CI: 0.8, 6.6) for a twofold increase in acrylamide and glycidamide adduct levels, respectively. Additionally, a twofold increase in glycidamide adducts was associated with lower cord plasma insulin levels, particularly among newborns of non-smoking mothers (−11.2% [95% CI: −19.5, −0.1]).Cord plasma insulin seemed to mediate the association between glycidamide adducts and birth weight. ConclusionsA decrease in cord plasma insulin levels may be (a marker of) a mechanism by which gestational acrylamide exposure is associated with decreased fetal growth. The possible health consequences of the associations between gestational acrylamide exposure and thyroid hormones and neurotrophins warrant future study.

Cord blood acrylamide levels and birth size, and interactions with genetic variants in acrylamide-metabolising genes

BackgroundUp to now, 3 epidemiological studies have shown clear inverse associations between prenatal acrylamide exposure and birth size. In addition to studying the association between acrylamide and birth size, we investigated the interaction between acrylamide and polymorphisms in acrylamide-metabolising genes, with the aim of probing the causality of the inverse relationship between acrylamide and fetal growth.MethodsWe investigated the association between prenatal acrylamide exposure (acrylamide and glycidamide hemoglobin adduct levels (AA-Hb and GA-Hb) in cord blood) and birth weight, length and head circumference in 443 newborns of the ENVIRONAGE (ENVIRonmental influence ON AGEing in early life) birth cohort. In addition, we studied interaction with single nucleotide polymorphisms (SNPs) in CYP2E1, EPHX1 and GSTP1, using multiple linear regression analysis.ResultsAmong all neonates, the body weight, length and head circumference of neonates in the highest quartile was − 101 g (95% CI: − 208, 7; p for trend = 0.12), − 0.13 cm (95% CI: − 0.62, 0.36; p for trend = 0.69) and − 0.41 cm (− 0.80, − 0.01; p for trend = 0.06) lower, respectively, compared to neonates in the lowest quartile of AA-Hb in cord blood, For GA-Hb, the corresponding effect estimates were − 222 g (95% CI: − 337, − 108; p for trend = 0.001), − 0.85 (95% CI: − 1.38, − 0.33; p for trend = 0.02) and − 0.55 (95% CI: − 0.98, − 0.11; p for trend = 0.01), respectively. The associations for GA-Hb were similar or stronger in newborns of non-smoking mothers. There was no statistically significant interaction between acrylamide exposure and the studied genetic variations but there was a trend of stronger inverse associations with birth weight and head circumference among newborns with homozygous wildtypes alleles for the CYP2E1 SNPS and with variant alleles for a GSTP1 SNP (rs1138272).ConclusionsPrenatal dietary acrylamide exposure, specifically in the form of its metabolite glycidamide, was inversely associated with birth weight, length and head circumference. The interaction pattern with SNPs in CYP2E1, although not statistically significant, is an indication for the causality of this association. Other studies are needed to corroborate this finding.

Maternal Smoking and Metabolic Health Biomarkers in Newborns.

BackgroundMaternal smoking has been associated with elevated risk of type 2 diabetes among the offspring in adulthood. The mechanisms underlying this fetal “programming” effect remain unclear. The present study sought to explore whether maternal smoking affects metabolic health biomarkers in fetuses/newborns.MethodsIn a prospective singleton pregnancy cohort (n = 248), we compared metabolic health biomarkers in the newborns of smoking and non-smoking mothers. Outcomes included cord plasma insulin, proinsulin, insulin-like growth factor I (IGF-I), IGF-II, leptin and adiponectin concentrations, glucose-to-insulin ratio (an indicator of insulin sensitivity) and proinsulin-to-insulin ratio (an indicator of β-cell function).ResultsIndependent of maternal (glucose tolerance, age, ethnicity, parity, education, body mass index, alcohol use) and infant (sex, gestational age, birth weight z score, mode of delivery, cord blood glucose concentration) characteristics, the newborns of smoking mothers had lower IGF-I concentrations (mean: 6.7 vs. 8.4 nmol/L, adjusted p = 0.006), and marginally higher proinsulin-to-insulin ratios (0.94 vs. 0.72, adjusted p = 0.06) than the newborns of non-smoking mothers. Cord plasma insulin, proinsulin, IGF-II, leptin and adiponectin concentrations and glucose-to-insulin ratios were similar in the newborns of smoking and non-smoking mothers.ConclusionsMaternal smoking was associated with decreased fetal IGF-I levels, and borderline lower fetal β-cell function. Larger cohort studies are required to confirm the latter finding. The preliminary findings prompt the hypothesis that these early life metabolic changes may be involved in the impact of maternal smoking on future risk of metabolic syndrome related disorders in the offspring.

Maternal cigarette smoking and its effect on neonatal lymphocyte subpopulations and replication

BackgroundSignificant immunomodulatory effects have been described as result of cigarette smoking in adults and pregnant women. However, the effect of cigarette smoking during pregnancy on the lymphocyte subpopulations in newborns has been discussed, controversially.MethodsIn a prospective birth cohort, we analyzed the peripheral lymphocyte subpopulations of smoking (SM) and non-smoking mothers (NSM) and their newborns and the replicative history of neonatal, mostly naive CD4 + CD45RA + T cells by measurements of T-cell-receptor-excision-circles (TRECs), relative telomere lengths (RTL) and the serum cytokine concentrations.ResultsSM had higher lymphocyte counts than NSM. Comparing SM and NSM and SM newborns with NSM newborns, no significant differences in proportions of lymphocyte subpopulations were seen. Regardless of their smoking habits, mothers had significantly lower naive T cells and higher memory and effector T cells than newborns. NSM had significantly lower percentages of CD4 + CD25++ T cells compared to their newborns, which was not significant in SM. There were no differences regarding cytokine concentrations in newborns of SM and NSM. However, NSM had significantly higher Interleukin-7 concentrations than their newborns. Regardless of smoking habits of mothers, newborns had significantly longer telomeres and higher TRECs than their mothers. Newborns of SM had significantly longer telomeres than newborns of NSM.ConclusionsApart from higher lymphocyte counts in SM, our results did not reveal differences between lymphocyte subpopulations of SM and NSM and their newborns, respectively. Our finding of significantly longer RTL in newborns of SM may reflect potential harm on lymphocytes, such as cytogenetic damage induced by smoking.

A longitudinal study on the effects of maternal smoking and secondhand smoke exposure during pregnancy on neonatal neurobehavior

Maternal smoking during pregnancy is one of the most modifiable causes of morbidity and mortality for both pregnant women and their fetuses. The long-term effects of prenatal exposure to smoke on child behavior and development have been the subject of more extensive research than have the short-term effects. Therefore, the aim of this work is to examine the effects of smoke exposure during pregnancy on neonatal behavior, including in our study a group of mothers exposed to secondhand smoke. The behavior of 282 healthy full-term newborns was assessed using the Neonatal Behavior Assessment Scale (NBAS) at 48–72h of life. Sixty-two mothers smoked during pregnancy (no mother smoked more than 15cig/day) and 17 were exposed to secondhand smoke. After adjusting for socio-demographic and obstetric factors, both newborns whose mothers smoked and those whose mothers were exposed to secondhand smoke showed significantly lower scores in the habituation cluster than non-smoking mothers. Exposure to secondhand smoke was also related to lower motor system cluster scores as well as some supplementary items and the newborns of smoking mothers showed significantly lower scores in the state regulation cluster and in some items of the state organization cluster than the newborns of non-smoking mothers. We conclude that active and passive smoking during pregnancy affects several aspects of neurobehavioral development, regardless of socio-demographic, obstetric and pediatric factors.

Micronuclei levels in mothers and their newborns from regions with different types of air pollution

The aim of this study was to analyze genetic damage in human lymphocytes measured using automated image analysis of micronuclei (MN) in a group of 178 mothers and their newborns from two locations in the Czech Republic. The concentrations of benzo[a]pyrene (B[a]P), particulate matter of aerodynamic diameter <2.5 μm (PM2.5) and benzene were measured by stationary monitoring in the winter season of 2008/2009 in the capital city of Prague and in Ceske Budejovice, a regional city in a rural area. The 3-month mean concentration of B[a]P before delivery was lower in Prague in comparison with Ceske Budejovice: 1.9 ± 0.5 ng/m 3 vs. 3.2 ± 0.2 ng/m 3 ( p < 0.001). The opposite trend was found for PM2.5 and benzene: 27.0 ± 2.5 μg/m 3 and 2.5 ± 0.5 μg/m 3 vs. 24.5 ± 0.7 μg/m 3 and 2.1 ± 0.8 μg/m 3 ( p < 0.001) for Prague vs. Ceske Budejovice, respectively. The average age of the mothers was 31 years (range, 18–49 years). The frequencies of MN per 1000 binucleated cells were 8.35 ± 3.06 vs. 6.47 ± 2.35 ( p < 0.001) for mothers from Prague and Ceske Budejovice, respectively, and 2.17 ± 1.32 vs. 3.82 ± 2.43 ( p < 0.001) for newborns from Prague and Ceske Budejovice, respectively. Other factors, including vitamin intake, exposure to tobacco smoke, body mass index (BMI) before pregnancy, the education level of the mothers and the impact of the mothers’ and fathers’ ages were analyzed in our study. The results suggest that the different sensitivity of the study groups to various mixtures of carcinogenic pollutants could be affected by significant differences in lifestyle factors. Possible higher genetic damage was analyzed in newborns of smoking mothers, and the birth weight of this group was 7.4% lower ( p < 0.05) in comparison with the newborns of nonsmoking mothers. No impact of the age of the mothers or fathers on MN frequency in the newborns was observed.

Metabolites of a tobacco-specific carcinogen in urine from newborns.

Cigarette smoking during pregnancy can result in fetal exposure to carcinogens that are transferred from the mother via the placenta, but little information is available on fetal uptake of such compounds. We analyzed samples of the first urine from newborns whose mothers did or did not smoke cigarettes for the presence of metabolites of the potent tobacco-specific transplacental carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The urine was collected and analyzed for two metabolites of NNK, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronide (NNAL-Gluc). Gas chromatography and nitrosamine-selective detection, with confirmation by mass spectrometry, were used in the analyses, which were performed without knowledge of the origin of the urine samples. NNAL-Gluc was detected in 22 (71%) of 31 urine samples from newborns of mothers who smoked; NNAL was detected in four of these 31 urine samples. Neither compound was detected in the 17 urine samples from newborns of mothers who did not smoke. The arithmetic mean level of NNAL plus NNAL-Gluc in the 27 newborns of smokers for which both analytes were quantified was 0.14 (95% confidence interval [CI] = 0.083-0.200) pmol/mL. The levels of NNAL plus NNAL-Gluc in the urine from these babies were statistically significantly higher than those in the urine from newborns of nonsmoking mothers (geometric means = 0.062 [95% CI = 0.035-0.110] and 0.010 [considered as not detected; no confidence interval], respectively; two-sided P<.001). NNAL plus NNAL-Gluc levels in the 18 positive urine samples in which both analytes were quantified ranged from 0.045 to 0.400 pmol/mL, with an arithmetic mean level of 0.20 (95% CI = 0.14-0.26) pmol/mL, about 5%-10% of the levels of these compounds detected in the urine from adult smokers. Two metabolites of the tobacco-specific transplacental carcinogen NNK can be detected in the urine from newborns of mothers who smoked cigarettes during pregnancy.

The effect of paternal smoking on the birthweight of newborns whose mothers did not smoke. Group Health Medical Associates.

We examined the relationship of paternal smoking habits to birthweight in a cohort of infants enrolled at birth (n = 1219). To assess validity of parental smoking reports, cord serum levels of cotinine were measured in 175 newborns. A mean birthweight deficit of 88 g was found in newborns of nonsmoking mothers whose fathers smoked more than 20 cigarettes/day. Only 2 of 138 newborns whose mothers said they were nonsmokers had cotinine levels indicating that their mothers were active smokers. Among infants of nonsmoking mothers, detectability of cotinine in cord blood was significantly correlated with the number of cigarettes smoked daily by fathers. These data suggest that fetal growth may be adversely affected when the mother is passively exposed to tobacco smoke during pregnancy.

Ultrastructural changes in preputial neural tissues: effects of maternal smoking.

The fetal prepuce was studied for neural changes due to maternal smoking during pregnancy. Prepuces from 10 newborns whose mothers smoked throughout pregnancy and from 4 newborns of nonsmoking mothers were examined by transmission electron microscope. Significant ultrastructural changes were seen in the neural tissues of the newborns of smoking mothers. The ultrastructural changes observed were: (1) local aggregation of mitochondria; (2) many myelin bodies, and (3) dilated Golgi apparatus and dilated endoplasmic reticulum of the Schwann cell. Similar changes have been reported in neuropathies due to various drugs, chemicals and deficiency states. These findings suggest adverse effects on fetal preputial neural tissue due to maternal smoking.