Postnatal Cardiovascular Consequences in the Offspring of Pregnant Rats Exposed to Smoking and Smoking Cessation Pharmacotherapies

Developmental nicotine exposure alters cardiovascular structure and function in neonatal and juvenile rats

Here we test the hypothesis that continuous nicotine exposure throughout pre- and postnatal development (developmental nicotine exposure, DNE) alters the cardiovascular structure and function in neonatal and juvenile rats. Echocardiography showed that DNE reduced left ventricular mass, left ventricular outflow tract (LVOT) diameter, and posterior wall thickness, but only in females. Both male and female DNE rats had a lower end-systolic volume, higher ejection fraction, and increased fractional shortening, with unchanged stroke volume and cardiac output. Left ventricular single cardiac myocytes from male and female DNE animals exhibited increased calcium-evoked maximal tension with no effect on EC50. Tail-cuff plethysmography in awake rats showed that DNE males had lower systolic blood pressure and higher heart rate than control males. No significant changes in preload, afterload, or the in vitro renal artery response to vasodilators were observed. The results suggest that DNE enhances myocyte tension-generating capacity, possibly compensating for an unknown developmental insult, which may differ in males and females. Although this adaptation maintains normal resting cardiac function, it may lead to reduced cardiac reserve, increased energy demand, and elevated oxidative stress, potentially compromising both short- and long-term cardiovascular health in developing neonates.NEW & NOTEWORTHY Developmental nicotine exposure (DNE) induced cardiovascular changes in neonatal/juvenile rats. Relative to controls, females had reduced left ventricular mass and dimensions, while both sexes had increased ejection fraction and fractional shortening. DNE increased calcium-evoked tension in cardiac myocytes, suggesting an adaptive mechanism as resting cardiac output was preserved. Despite normal resting function, these changes may reduce cardiac reserve, potentially compromising long-term cardiovascular health. These novel findings highlight how DNE disrupts cardiovascular development and function.

In utero chronic intermittent nicotine aerosol exposure increases ischemic heart injury in adult offspring via programming of Angiotensin II receptor-derived TGFβ/ROS/Akt signaling pathway

BACKGROUND

In utero cigarette smoking/nicotine exposure during pregnancy significantly affects fetal development and increases the risk of cardiovascular disease late in life. However, the underlying molecular mechanisms remain largely unknown. We tested the hypothesis that fetal nicotine aerosol exposure reprograms ischemia-sensitive gene expressions, resulting in increased heart susceptibility to ischemic injury and cardiac dysfunction in adulthood.

METHODS

Pregnant rats were exposed to chronic intermittent nicotine aerosol (CINA) or saline aerosol control from gestational day 4 to day 21. Experiments were performed on 6-month-old adult offspring.

RESULTS

CINA exposure increased ischemia-induced cardiac injury and cardiac dysfunction compared to the control group, which was associated with over- expression of angiotensin II receptor (ATR) protein in the left ventricle (LV) of adult offspring. Meanwhile, CINA exposure up-regulated cardiac TGF-β/SMADs family proteins in the LV. In addition, CINA exposure enhanced cardiac reactive oxygen species (ROS) production and increased the DNA methylation level. The levels of phosphorylated-Akt were upregulated but LC3B-II/I protein abundances were downregulated in the hearts isolated from the CINA-treated group.

CONCLUSION

Fetal nicotine aerosol exposure leads to cardiac dysfunction in response to ischemic stimulation in adulthood. Two molecular pathways are implicated. First, fetal CINA exposure elevates cardiac ATR levels, affecting the TGFβ-SMADs pathway. Second, heightened Angiotensin II/ATR signaling triggers ROS production, leading to DNA hypermethylation, p-Akt activation, and autophagy deficiency. These molecular shifts in cardiomyocytes result in the development of a heart ischemia-sensitive phenotype and subsequent dysfunction in adult offspring.

Maternal electronic cigarette use during pregnancy affects long-term arterial function in offspring

Vaping, or electronic cigarette (ecig) use, is prevalent among pregnant women, although little is known about the effects of perinatal ecig use on cardiovascular health of the progeny (even when using nicotine-free e-liquid). Maternal toxicant inhalation may adversely affect vital conduit vessel development. We tested the hypothesis that perinatal exposure to maternal vaping would lead to a dose-dependent dysfunction that would persist into later life of offspring. Pregnant Sprague-Dawley rats were exposed to either nicotine-free (ecig0) or nicotine-containing ecig aerosol (18 mg/mL, ecig18) starting on gestational day 2 and continued until pups were weaned (postnatal day 21). Pups were never directly exposed. Conduit artery function (stiffness and reactivity) and structure were assessed in 3- and 7-mo-old offspring. At 3 mo, pulse wave velocity (PWV) in the ecig0 and ecig18 offspring was significantly higher than controls in both the 20 puffs/day (6.6 ± 2.1 and 4.8 ± 1.3 vs. 3.2 ± 0.7 m/s, respectively, P < 0.05, means ± SD) and in 60 puffs/day exposure cohort (7.5 ± 2.8 and 7.5 ± 2.5 vs. 3.2 ± 0.5 m/s, respectively, P < 0.01). Wire myography revealed (range of 23%-31%) impaired aortic relaxation in all ecig exposure groups (with or without nicotine). Incubation of vessels with TEMPOL or Febuxostat reversed the aortic dysfunction, implicating the involvement of reactive oxygen species. Nearly identical changes and pattern was seen in vascular outcomes of 7-mo-old offspring. The take-home message from this preclinical study is that maternal vaping during pregnancy, with or without nicotine, leads to maladaptations in vascular (aortic) development that persist into adult life of offspring.NEW & NOTEWORTHY We observe a significant alteration in arterial structure and function in adolescent and adult offspring due to developmental exposure to toxicants resulting from perinatal maternal vaping. Taken together with previous work that described lasting dysfunction in cerebral microvasculature in offspring, these data underscore the adverse consequences of maternal exposure to electronic cigarette aerosol in conduit and resistance vessels alike, irrespective of nicotine content.

Maternal PFOS exposure during rat pregnancy causes hypersensitivity to angiotensin II and attenuation of endothelium-dependent vasodilation in the uterine arteries

Epidemiological studies show a strong association between environmental exposure to perfluorooctane sulfonic acid (PFOS) and preeclampsia and fetal growth restriction; however, the underlying mechanisms are unclear. We tested the hypothesis that gestational PFOS exposure leads to pregnancy complications via alterations in uterine vascular endothelium-independent angiotensin II-related mechanisms and endothelium-derived factors such as nitric oxide. Pregnant Sprague Dawley rats were exposed to PFOS 0.005, 0.05, 0.5, 5, 10, and 50 μg/mL through drinking water from gestational day 4 to 20, and dams with PFOS 50 μg/mL were used to assess mechanisms. PFOS exposure dose-dependently increased maternal blood pressure but decreased fetal weights. Uterine artery blood flow was lower and resistance index was higher in the PFOS dams. In PFOS dams, uterine artery contractile responses to angiotensin II were significantly greater, whereas contractile responses to K+ depolarization and phenylephrine were unaffected. Plasma angiotensin II levels were not significantly different between control and PFOS dams; however, PFOS exposure significantly increased AGTR1 and decreased AGTR2 protein levels in uterine arteries. Endothelium-dependent relaxation response to acetylcholine was significantly reduced with decreased endothelial nitric oxide synthase expression in the uterine arteries of PFOS dams. Left ventricular hypertrophy and fibrosis were observed, along with increased ejection fraction and fractional shortening in PFOS dams. These results suggest that elevated maternal PFOS levels decrease uterine blood flow and increase vascular resistance via heightened angiotensin II-mediated vasoconstriction and impaired endothelium-dependent vasodilation, which provides a molecular mechanism linking elevated maternal PFOS levels with gestational hypertension and fetal growth restriction.

Gestational Intermittent Hypoxia Induces Sex-Specific Impairment in Endothelial Mechanisms and Sex Steroid Hormone Levels in Male Rat Offspring

Obstructive sleep apnea (OSA) is highly prevalent during gestation and is linked with adverse fetal outcomes. We examined whether gestational intermittent hypoxia (GIH), the main feature of OSA, leads to sex-specific alterations in cardiovascular function and vascular mechanisms in the offspring. Pregnant rats exposed to intermittent hypoxia or ambient air from gestation days 10 to 21 and their offspring were used for the study. GIH exposure did not affect water and food intake in dams. Compared to controls, the male and female offspring born to GIH dams were smaller in weight by 14% and 12%, respectively, and exhibited catch-up growth. Cardiac function was not affected in either GIH males or females. At 12 weeks of age, blood pressure was increased in GIH males, but not GIH females, compared to their control counterparts. While mesenteric arterial contractile responses to phenylephrine and endothelin were unaffected in GIH males and females, relaxation response to acetylcholine was reduced in GIH males but not GIH females. Relaxation to sodium nitroprusside was unaffected in both GIH males and females. Total eNOS expression was not affected, but phospho(Ser1177)-eNOS levels were decreased in GIH males. eNOS expression and its phosphorylation status were unaffected in GIH females. Serum testosterone and estradiol levels were higher in GIH males but were unaltered in GIH females. Together, these findings suggest that GIH leads to a sex-specific increase in blood pressure in adult male offspring with blunted endothelium-mediated relaxation, decreased eNOS activity, and elevated sex steroid hormone levels.

Evaluation of Plasma Asymmetric Dimethylarginine Levels and Abdominal Aortic Intima-Media Thickness in Infants of Smoker Mothers

OBJECTIVE

Smoking during pregnancy has harmful effects on the fetus and infant. Although some studies suggest that exposure to fetal-maternal smoking adversely affects both fetal growth and cardiovascular development, the mechanisms and biochemical consequences of smoking in pregnancy and newborns are not yet fully understood. We aimed to investigate whether maternal smoking during pregnancy causes fetal cardiovascular effect by measuring serum asymmetric dimethylarginine (ADMA) level and abdominal aortic intima-media thickness (aIMT).

STUDY DESIGN

This prospective study was conducted in newborns of smoking mothers and never-smoker control mothers during their pregnancies. The babies were evaluated echocardiographically on the first day following birth. In two-dimensional mode, abdominal aIMT measurements were performed. ADMA was measured in umbilical cord blood at birth.

RESULTS

There were 25 mothers in the study group and 25 mothers in the control group. Serum ADMA levels were 0.459 ± 0.119 μmol/L in the study group and 0.374 ± 0.1127 μmol/L in the control group (p = 0.034). The aIMT value in the study group was 0.84 ± 0.026 mm and the aIMT value in the control group was 0.63 ± 0.011 mm (p = 0.005).

CONCLUSION

We found that both the serum ADMA and the aIMT significantly increased in the group with newborns of smoker mothers compared with the group of the newborns of never-smoker mothers. It may also be suggested that exposure to fetal-maternal smoking adversely affects cardiovascular development.

KEY POINTS

· It is a known fact that smoking during pregnancy has harmful effects on the development of the fetus and infant.. · We found that both the serum ADMA and aIMT were significantly higher in the group of infants of smoker mothers..

Inhibition of DNA methylation in newborns reprograms ischemia-sensitive biomarkers resulting in development of a heart ischemia-sensitive phenotype late in life

Adverse environmental stress exposure at critical perinatal stages can alter cardiovascular development, which could persist into adulthood and develop a cardiovascular dysfunctional phenotype late in life. However, the underlying molecular mechanisms remain largely unknown. The present study provided a direct evidence that DNA methylation is a key epigenetic mechanism contributing to the developmental origins of adult cardiovascular disease. We hypothesized that DNA hypomethylation at neonatal stage alters gene expression patterns in the heart, leading to development of a cardiac ischemia-sensitive phenotype late in life. To test this hypothesis, a DNA methylation inhibitor 5-Aza-2-deoxycytidine (5-Aza) was administered in newborn rats from postnatal day 1-3. Cardiac function and related key genes were measured in 2-week- and 2-month-old animals, respectively. 5-Aza treatment induced an age- and sex-dependent inhibition of global and gene-specific DNA methylation levels in left ventricles, resulting in a long-lasting growth restriction but an asymmetry increase in the heart-to-body weight ratio. In addition, treatment with 5-Aza enhanced ischemia and reperfusion-induced cardiac dysfunction and injury in adults as compared with the saline controls, which was associated with up-regulations of miRNA-181a and angiotensin II receptor type 1 & 2 gene expressions, but down-regulations of PKCε, Atg5, and GSK3β gene expressions in left ventricles. In conclusion, our results provide compelling evidence that neonatal DNA methylation deficiency is a key mechanism contributing to differentially reprogram cardiac gene expression patterns, leading to development of a heart ischemia-sensitive phenotype late in life.

Reprogramming of miR-181a/DNA methylation patterns contribute to the maternal nicotine exposure-induced fetal programming of cardiac ischemia-sensitive phenotype in postnatal life

Background: E-cigarette and other novel electronic nicotine delivery systems (ENDS) have recently entered the market at a rapid pace. The community desperately needs answers about the health effects of ENDS. The present study tested the hypothesis that perinatal nicotine exposure (PNE) causes a gender-dependent increase in vulnerability of the heart to ischemia-reperfusion (I/R) injury and cardiac dysfunction in male rat offspring via reprogramming of the miRNA-181a (miR-181a)-mediated signaling pathway and that miR-181a antisense could rescue this phenotype. Methods: Nicotine or saline was administered to pregnant rats via subcutaneous osmotic minipumps from gestational day 4 until postnatal day 10. Cardiac function and molecular biological experiments were conducted in ~3- month-old offspring. Results: PNE enhanced I/R-induced cardiac dysfunction and infarction in adult male but not in female offspring, which was associated with miR-181a over-expression in left ventricle tissues. In addition, PNE enhanced offspring cardiac angiotensin receptor (ATR) expressions via specific CpG hypomethylation of AT₁R/AT₂R promoter. Furthermore, PNE attenuated cardiac lncRNA H19 levels, but up-regulated cardiac TGF-β/Smads family proteins and consequently up-regulated autophagy-related protein (Atg-5, beclin-1, LC3 II, p62) expression in the male offspring. Of importance, treatment with miR-181a antisense eliminated the PNE's effect on miR-181a expression/H19 levels and reversed PNE-mediated I/R-induced cardiac infarction and dysfunction in male offspring. Furthermore, miR-181a antisense also attenuated the effect of PNE on AT₁R/AT₂R/TGF-β/Smads/autophagy-related biomarkers in the male offspring. Conclusion: Our data suggest that PNE could induce a reprogramming of cardiac miR-181a expression/DNA methylation pattern, which epigenetically modulates ATR/TGF-β/autophagy signaling pathways, leading to gender-dependent development of ischemia-sensitive phenotype in postnatal life. Furthermore, miR-181a could severe as a potential therapeutic target for rescuing this phenotype.

Paternal exposure to bupropion affects postnatal development in the offspring

The aim of this study was to evaluate whether paternal exposure to bupropion hydrochloride (BUP), an inhibitor of dopamine and noradrenaline reuptake, would affect the postnatal development of offspring. Male mice were divided into a BUP-treated (40mgkg-1day-1 by gavage, 45 days) or control (saline by gavage, 45 days) group (n=20 in each group). From Day 35 to Day 45 of treatment, males were allowed to mate with drug-naïve female mice. Postnatal development of the offspring (both sexes) was evaluated from Postnatal day (PND) 1 to PND60. Physical development parameters (weight gain, body length, incisor eruption, pinna detachment), anogenital distance, vaginal opening, reflexes (palmar grasp, surface righting, negative geotaxis and adult gait) and some behavioural parameters (locomotor activity and anxiety-like behaviour) were altered in the offspring of BUP-treated males. The results demonstrate that paternal exposure to BUP induces long-lasting changes in the postnatal development of the offspring.

The burden of personality disorders on the DSM 5 addiction to tobacco during pregnancy

BACKGROUND

Tobacco smoking is a major health concern. Many women smoke during their reproductive years, some of them during their pregnancy. Adverse outcomes for the newborns physical health are well recognized, while the influence on their mental health is still under investigation. We aim at demonstrating the contribution of maternal personality disorders in maintaining addiction to tobacco during pregnancy, to underline their role and the need of their detection as a preventive effort.

METHOD

150 women, consecutively admitted to the Perinatal Psychiatric Outpatient Department were tested with the SCID II, CTQ, WHOQOL-BREF, EPDS, BDI and BAI. Tobacco use disorder was attested with the fulfillment of DSM 5 criteria.

RESULTS

46% (n = 69) of the sample was affected by at least one personality disorder ("PD⁺"). "PD⁺" showed a significant higher rate of pregnant women addicted to tobacco (p = 0.021). The average number of cigarettes per day was notably distinct, since patients affected by "NPD" smokes twice the amount compared to "PD^-" and "other PDs", while those affected by Borderline PD has a halfway consumption (7.20 ± 5.54 vs 3.37 ± 4.62 vs 3 ± 3.39 vs 5.50 ± 4.10). ANOVA and POST HOC showed a significance between "NPD" and "other PDs" (p = 0.035), and "other PDs" has significantly the highest rate of active smokers.

CONCLUSION

Personality disorders demonstrate to be a clear contributor in supporting addiction to tobacco during pregnancy. Short and long term health and mental consequences attested in the newborn, encourage awareness in detecting tobacco dependency during this sensitive period. The inclusion of personality evaluation and management in tobacco dependency treatment programs is strictly encouraged to boost their efficiency and increase tobacco abstinence.