Mainstream smoke and sidestream smoke affect the cardiac differentiation of mouse embryonic stem cells discriminately

Comparative study of e-cigarette aerosol and cigarette smoke effect on ex vivo embryonic chick lung explants

Electronic cigarette usage has significantly expanded among young people and pregnant women in the last decade. Although there are already some data regarding the short- and long-term consequences of e-cigarettes on human health, their effect on embryo and lung development still needs to be fully disclosed. In this sense, this study describes, for the first time, the impact of electronic cigarette aerosol on early lung development. For this purpose, ex vivo chick (Gallus gallus) embryonic lungs were cultured in vitro for 48 h in e-cigarette aerosol exposed-medium or unexposed medium. Chick lung explants were also cultured in a cigarette smoke-exposed medium for comparison purposes. Lung explants were morphologically analyzed to assess the impact on lung growth. Additionally, TNF-α levels were determined in the supernatant as a marker of pro-inflammatory response. The results suggest that electronic cigarette aerosol impairs lung growth and promotes lung inflammation. However, its impact on early lung growth seems less detrimental than conventional cigarette smoke. This work provides significant data regarding the impact of e-cig aerosol, adding to the efforts to fully understand its effect on embryo development. The validation of these effects may eventually lead to new tobacco control recommendations for pregnant women.

Epigenetics and Congenital Heart Diseases

Congenital heart disease (CHD) is a frequent occurrence, with a prevalence rate of almost 1% in the general population. However, the pathophysiology of the anomalous heart development is still unclear in most patients screened. A definitive genetic origin, be it single-point mutation or larger chromosomal disruptions, only explains about 35% of identified cases. The precisely choreographed embryology of the heart relies on timed activation of developmental molecular cascades, spatially and temporally regulated through epigenetic regulation: chromatin conformation, DNA priming through methylation patterns, and spatial accessibility to transcription factors. This multi-level regulatory network is eminently susceptible to outside disruption, resulting in faulty cardiac development. Similarly, the heart is unique in its dynamic development: growth is intrinsically related to mechanical stimulation, and disruption of the intrauterine environment will have a direct impact on fetal embryology. These two converging axes offer new areas of research to characterize the cardiac epigenetic regulation and identify points of fragility in order to counteract its teratogenic consequences.

Malondialdehyde Level and Tissue Apoptosis Count as an Early-Detection Marker of Oral Potentially Malignant Disorders

OBJECTIVES

 The malondialdehyde (MDA) level and TA count represent the progression of oral potentially malignant disorders (OPMD) to malignancy and thus may be used as an indicator of oral epithelial dysplasia (OED). This study aimed to determine the MDA level and tissue apoptosis (TA) count in oropharyngeal tissue of Wistar rats exposed to sidestream cigarette smoke.

MATERIALS AND METHODS

 Wistar rats were divided into three groups: T4 group (4-week cigarette smoke exposure), T8 group (8-week cigarette smoke exposure), and control group, which was not exposed to cigarette smoke. The oropharyngeal tissue of the rats from each group was examined histopathologically to count the number of apoptotic cells, and then the blood serum was made to measure the MDA level.

STATISTICAL ANALYSIS

 Bonferroni test was performed to see the differences in each group for MDA level. While the data from tissue apoptosis were analyzed using Mann-Whitney U test for the significance. All data were considered significant if p < 0.05.

RESULTS

 The MDA level and TA count increased as the duration of cigarette smoke exposure increased. In the T8 group, the MDA level and TA count were significantly higher compared with the T4 and control groups with a p-value < 0.05.

CONCLUSIONS

 Exposure to sidestream cigarette smoke increased the TA count and MDA level in the oropharyngeal tissue of Wistar rats. The TA count and MDA level may be used as markers of OPMD.

Environmental Alterations during Embryonic Development: Studying the Impact of Stressors on Pluripotent Stem Cell-Derived Cardiomyocytes

Non-communicable diseases (NCDs) sauch as diabetes, obesity and cardiovascular diseases are rising rapidly in all countries world-wide. Environmental maternal factors (e.g., diet, oxidative stress, drugs and many others), maternal illnesses and other stressors can predispose the newborn to develop diseases during different stages of life. The connection between environmental factors and NCDs was formulated by David Barker and colleagues as the Developmental Origins of Health and Disease (DOHaD) hypothesis. In this review, we describe the DOHaD concept and the effects of several environmental stressors on the health of the progeny, providing both animal and human evidence. We focus on cardiovascular diseases which represent the leading cause of death worldwide. The purpose of this review is to discuss how in vitro studies with pluripotent stem cells (PSCs), such as embryonic and induced pluripotent stem cells (ESC, iPSC), can underpin the research on non-genetic heart conditions. The PSCs could provide a tool to recapitulate aspects of embryonic development “in a dish”, studying the effects of environmental exposure during cardiomyocyte (CM) differentiation and maturation, establishing a link to molecular mechanism and epigenetics.

Associations and interaction effects of maternal smoking and genetic polymorphisms of cytochrome P450 genes with risk of congenital heart disease in offspring: A case-control study

To assess associations and interactions of maternal smoking and cytochrome P450 (CYP450) genetic variants with the developments of congenital heart disease (CHD) and specific subtypes.A case-control study of 654 cases and 666 controls was conducted from November 2017 to March 2020. The exposures of interest were maternal active and passive smoking before/in the early pregnancy and CYP450 genetic polymorphisms. Data were analyzed using the Chi-square test and logistic regression analysis.After adjusting for the potential confounding factors, our study showed maternal active (ORadj = 2.34, 95%CI: 1.19-4.60) or passive (ORadj = 1.76, 95%CI: 1.34-2.31) smoking before pregnancy, passive smoking in the early pregnancy (ORadj = 3.05, 95%CI: 2.26-4.12), as well as polymorphisms of CYP450 at rs1065852 (G/A vs G/G: ORadj = 1.46, 95%CI: 1.07-1.99; A/A vs G/G: ORadj = 1.63, 95%CI: 1.15-2.33) and rs16947 (A/A vs G/G: ORadj = 3.61, 95%CI: 2.09-6.23), were significantly associated with risk of total CHD in offspring. Similar results were also found for some subtypes of CHD. Additionally, significant interactions between maternal smoking and CYP450 genes on the risk of CHD were observed.Maternal smoking and CYP450 genetic variants were associated with increased risk of CHD and specific subtypes in offspring. And the effects of CYP450 genes on CHD may be modified by maternal smoking.

Adverse effects of nicotine on cardiogenic differentiation from human embryonic stem cells detected by single-cell RNA sequencing

Tobacco smoking was one of the important adverse factors for congenital heart disease. The effects of nicotine, the main component of tobacco, on human embryonic cardiogenesis and related mechanisms remain poorly understood. This work used single-cell RNA sequencing to investigate the effects of nicotine on human embryonic stem cell (hESC) line H9 and its underlying mechanisms during cardiac differentiation. H9 was cultured in feeder-free medium and differentiated in cardiac condition medium when cells reached 90% confluent. Cell viability was detected by MTT after different concentration of nicotine treatment. Different expressed genes during cardiac differentiation was analyzed by single-cell RNA sequencing (scRNA-seq). Key gene expressions were confirmed by qPCR and Western blot. Results showed that 0.1μM-10μM nicotine did not affect H9 cell proliferation. Nicotine 1 μM down-regulated cardiac progenitor cell, mesoderm cell, smooth muscle cell and neural crest cell relatively. Snail1/2 regulating endocardial cushion development were downregulated apparently at differention day 6. Nicotine didn't affect bry-1 and mesp-1 but inhibited cardiac transcript factors. Consequently, the expression of cTnI, a marker of cardiomyocytes was decreased significantly. The data suggest direct adverse effects of nicotine on heart development at the single-cell level and offer a new approach for estimate drug and environmental toxicity on the pathogenesis of the embryonic cardiovascular system development.

Effects of cigarette smoke components on myocardial differentiation of mouse embryonic stem cells

The heart is the first organ formed in the developing fetus, and abnormal development of the heart is a major cause of fetal death. The adverse effects of cigarette smoke on the heart have been well established, but it is not well understood how cigarette smoke components regulate signaling molecules and cardiac specific functions during the early differentiation stage of the embryonic heart. In this study, we identified changes in the size of mouse embryoid bodies (mEBs) in response to treatment with cigarette smoke extract (CSE) via regulation of HDAC2, p53, p21, and cyclin D1 protein expression, which are cardiac differentiation and cell-cycle markers, respectively. In addition, exposure of mouse embryonic stem cells (mESCs) to cigarette smoke components inhibited myocardial differentiation and development through the expression of HDAC1, HDAC2, GATA4, NKX2-5, TBX5, HAND1, and Troponin I. Long-term exposure studies showed that CSE and nicotine may delay the development of mouse cardiomyocytes from mESCs and inhibit the contractibility, which is a fundamental function of the heart. Taken together, these findings suggest that cigarette smoke components, including nicotine, may affect abnormal myocardial differentiation and development.

Prenatal toxicity of the environmental pollutants on neuronal and cardiac development derived from embryonic stem cells

Pesticides, antibiotics, and industrial excipients are widely used in agriculture, medicine, and chemical industry, respectively. They often end up in the environment, not only being not easily decomposed but also being accumulated. Moreover, they may cause serious toxic problems such as reproductive and developmental defects, immunological toxicity, and carcinogenesis. Hence, they are called environmental pollutants. It is known that the environmental pollutants easily enter the body through various channels such as respiration, ingestion of food, and skin contact etc. in everyday life. If they enter the mother through the placenta, they can cause the disturbance in embryo development as well as malfunction of organs after birth because early prenatal developmental process is highly sensitive to toxic chemicals and stress. Embryonic stem cells (ESCs) that consist of inner cell mass of blastocyst differentiate into distinct cell lineages via three germ layers such as the ectoderm, mesoderm, and endoderm due to their pluripotency. The differentiation process initiated from ESCs reflects dynamic nature of embryonic development. Therefore, ESCs have been used as a useful tool to investigate early developmental toxicities of a variety of stress. Based on relatively recent scientific results, this review would address toxicity of a few chemical substances that have been widely used as pesticide, antibiotics, and industrial excipient on ESCs based-prenatal developmental process. This review further suggests how they act on the viability of ESCs and/or early stages of cardiac and neuronal development derived from ESCs as well as on expression of pluripotency and/or differentiation markers through diverse mechanisms.

Parental smoking and the risk of congenital heart defects in offspring: An updated meta-analysis of observational studies

OBJECTIVE

Although previous reviews confirmed maternal active smoking was significantly associated with risk of fetal congenital heart defects (CHDs), association between maternal passive smoking and paternal smoking and risk of CHDs is inconclusive nowadays; furthermore, a complete overview is lacking. A meta-analysis of observational studies was conducted to assess the risk of CHDs associated with maternal active and passive smoking and paternal smoking.

METHODS

Seven electronic databases were searched for qualified research up to June 2018. We summarized study characteristics and the summary risk estimates were calculated using either the random-effect model or fixed-effect model. Sensitivity and subgroup analysis were carried out to identify the potential heterogeneity moderators.

RESULTS

One hundred and twenty-five studies involving 137,574 CHDs cases in 8,770,837 study participants were included. Overall, maternal active (risk ratio (RR) = 1.25; 95% confidence interval (CI): 1.16-1.34; p < 0.01) and passive (RR = 2.24, 95% CI: 1.81-2.77; p < 0.01) smoking as well as paternal active smoking (RR = 1.74, 95% CI: 1.48-2.06; p < 0.01) were significantly associated with CHDs risk. For specific CHD subtypes, our study showed that maternal active smoking was significantly associated with risk of atrial septal defect (RR = 1.27, 95% CI: 1.02-1.59; p = 0.03) and right ventricular outflow tract obstruction (RR = 1.43, 95% CI: 1.04-1.97; p = 0.03). Relevant heterogeneity moderators have been identified by subgroup analysis. Sensitivity analysis yielded consistent results.

CONCLUSION

Maternal active smoking, maternal passive smoking as well as paternal smoking all increased the risk of CHDs in offspring. Preventing parental smoking during peri-pregnancy is a priority for CHDs prevention.

Molecular characterization of aldehydes and ketones in particle phase of mainstream and sidestream cigarette smoke

Aldehydes and ketones (AKs) in cigarette smoke are risk to humans and environment. Due to the complexity of itself and the interference of the smoke tar matrix, the aldehydes and ketones in particle phase (AKPs) of mainstream smoke (MSS) and sidestream smoke (SSS) have not been well investigated. In this study, the AKPs of MSS and SSS were derivatized into polar products by reaction with Girard T reagent. The derivatives were isolated rapidly by column chromatography and analysed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Fifteen species of aldehydes and ketones were detected by positive ion electrospray ionization (ESI) FT-ICR MS: O1-6, N1O1-4, N2O1-3 and N3O2-3. The total number of AKPs obtained by ESI FT-ICR MS in MSS and SSS is about 1100 and 970, respectively. After hydrolysis, the original AKPs were obtained and 63 carbonyls were identified and quantified by gas chromatography-mass spectrometry (GCMS). The nitrogen-containing and high-oxygen AKPs were further characterized by Orbitrap mass spectrometry. Structures of compounds with high relative abundance in the mass spectrum were speculated (e.g. a series of degradants of cembrenediol) by comparison with the results of GCMS.