Nicotine Directly Induces Endoplasmic Reticulum Stress Response in Rat Placental Trophoblast Giant Cells

Nicotine exposure during pregnancy leads to placental insufficiency impairing both fetal and neonatal development. Previous studies from our laboratory have demonstrated that in rats,nicotine augmented endoplasmic reticulum (ER) stress in association with placental insufficiency, however, the underlying mechanisms remain elusive. Therefore, we sought to investigate the possible direct effect of nicotine on ER stress in Rcho-1 rat placental trophoblastgiant (TG) cells during differentiation. Protein and/or mRNA expression of markers involved in ER stress (e.g., phosphorylated PERK, eIF2α, CHOP, BiP/GRP78) and trophoblast giant cell differentiation and function (e.g., Pl-1, Pgf, Hsd11b1, and Hsd11b2) were quantified via Western blot or Real-Time PCR. Nicotine treatment led to dose-dependent increases in the phosphorylation of PERK[Thr981] and eIF2α[Ser51], whereas pre-treatment with a nicotinic acetylcholine receptor (nAChR) antagonist (mecamylamine hydrochloride) blocked the induction of PERK phosphorylation, verifying the direct involvement of nicotine and nAChR binding. We next investigated select target genes known to play essential roles in placental TG cell differentiation and function (Pl-1, Pgf, Hsd11b1, and Hsd11b2), and found that nicotine significantly augmented the mRNA levels of Hsd11b1 in a dose-dependent manner. Furthermore, using Tauroursodeoxycholic acid (TUDCA), a safe bile acid known to improve protein chaperoning and folding, we were able to prevent nicotine-induced increases in both PERK phosphorylation and Hsd11b1 mRNA levels, revealing a potential novel therapeutic approach to reverse the deleterious effects of nicotine exposure in pregnancy. Collectively, these results implicate that nicotine, acting through its receptor, can directly augment ER stress and impair placental function

Maternal Nicotine Exposure Leads to Augmented Expression of the Antioxidant Adipose Tissue Triglyceride Lipase Long-Term in the White Adipose of Female Rat Offspring.

Globally, approximately 10-25% of women smoke during pregnancy. Since nicotine is highly addictive, women may use nicotine containing products like nicotine replacement therapies for smoking cessation, but the long-term consequences of early life exposure to nicotine remain poorly defined. Our laboratory has previously demonstrated that maternal nicotine exposed (MNE) rat offspring exhibit hypertriglyceridemia due to increased hepatic de novo lipogenesis. Hypertriglyceridemia may also be attributed to impaired white adipose tissue (WAT) lipid storage; however, the effects of MNE on WAT are not completely understood. We hypothesize that nicotine-induced alterations in adipose function (e.g. lipid storage) underlie dyslipidemia in MNE adults. Female 6 month old rats exposed to nicotine during gestation and lactation exhibited significantly decreased visceral adipocyte cell area by 40%, attributed, in part, to a 3-fold increase in adipose triglyceride lipase (ATGL) protein expression compared to vehicle. Given ATGL has antioxidant properties and in utero nicotine exposure promotes oxidative stress in various tissues, we next investigated if there was evidence of increased oxidative stress in MNE WAT. At both 3 weeks and 6 months, MNE offspring expressed 37-48% higher protein levels of SOD1 and SOD2 in WAT. Since oxidative stress can induce inflammation, we examined the inflammatory profile of WAT and found increased expression of cytokines (IL-1β, TNFα, and IL-6) by 44-61% at 6 months. Collectively, this suggests that the expression of WAT ATGL may be induced to counter MNE-induced oxidative stress and inflammation. However, higher levels of ATGL would further promote lipolysis in WAT, culminating in impaired lipid storage and long-term dyslipidemia

Maternal Nicotine Exposure Leads to Impaired Disulfide Bond Formation and Augmented Endoplasmic Reticulum Stress in the Rat Placenta

Maternal nicotine exposure has been associated with many adverse fetal and placental outcomes. Although underlying mechanisms remain elusive, recent studies have identified that augmented endoplasmic reticulum (ER) stress is linked to placental insufficiency. Moreover, ER function depends on proper disulfide bond formation-a partially oxygen-dependent process mediated by protein disulfide isomerase (PDI) and ER oxidoreductases. Given that nicotine compromised placental development in the rat, and placental insufficiency has been associated with poor disulfide bond formation and ER stress, we hypothesized that maternal nicotine exposure leads to both placental ER stress and impaired disulfide bond formation. To test this hypothesis, female Wistar rats received daily subcutaneous injections of either saline (vehicle) or nicotine bitartrate (1 mg/kg) for 14 days prior to mating and during pregnancy. Placentas were harvested on embryonic day 15 for analysis. Protein and mRNA expression of markers involved in ER stress (e.g., phosphorylated eIF2α, Grp78, Atf4, and CHOP), disulfide bond formation (e.g., PDI, QSOX1, VKORC1), hypoxia (Hif1α), and amino acid deprivation (GCN2) were quantified via Western blot and/or Real-time PCR. Maternal nicotine exposure led to increased expression of Grp78, phosphorylated eIF2α, Atf4, and CHOP (

Adverse effects of perinatal nicotine exposure on reproductive outcomes

Nicotine exposure during pregnancy through cigarette smoking, nicotine replacement therapies or e-cigarette use continues to be a widespread public health problem, impacting both fetal and postnatal health. Yet, at this time, there remains limited data regarding the safety and efficacy in using these nicotine products during pregnancy. Notably, reports assessing the effect of nicotine exposure on postnatal health outcomes in humans, including reproductive health, are severely lacking. Our current understanding regarding the consequences of nicotine exposure during pregnancy is limited to a few animal studies, which do not comprehensively address the underlying cellular mechanisms involved. This paper aims to critically review the current knowledge from human and animal studies regarding the direct and indirect effects (e.g. obesity) of maternal nicotine exposure, regardless of its source, on reproductive outcomes in pregnancy and postnatal life. Furthermore, this review highlights several key cellular mechanisms involved in these adverse reproductive deficits including oxidative stress, inflammation, and endoplasmic reticulum (ER) stress. By understanding the interplay of the cellular mechanisms involved, further strategies could be developed to prevent the reproductive abnormalities resulting from exposure to nicotine in utero and influence informed clinical guidelines for pregnant women

Δ9-Tetrahydrocannabinol leads to endoplasmic reticulum stress and mitochondrial dysfunction in human BeWo trophoblasts.

While studies have demonstrated that the main psychoactive component of cannabis, Δ9-tetrahydrocannabinol (Δ9-THC) alone induces placental insufficiency and fetal growth restriction, the underlying mechanisms remain elusive. Given that both (i) endoplasmic reticulum (ER) stress in pregnancy and (ii) gestational exposure to Δ9-THC leads to placental deficiency, we hypothesized that Δ9-THC may directly induce placental ER stress, influencing trophoblast gene expression and mitochondrial function. BeWo human trophoblast cells treated with Δ9-THC (3-30 μM) led to a dose-dependent increase in all ER stress markers and CHOP; these effects could be blocked with CB1R/CB2R antagonists. Moreover, expression of ER stress-sensitive genes ERRγ, VEGFA, and FLT-1 were increased by Δ9-THC, and abrogated with the ER stress inhibitor TUDCA. Δ9-THC also diminished mitochondrial respiration and ATP-coupling due to decreased abundance of mitochondrial chain complex proteins. Collectively, these findings indicate that Δ9-THC can directly augment ER stress resulting in aberrant placental gene expression and impaired mitochondrial function

Evaluation of the ability of a 2D ionisation chamber array and an EPID to detect systematic delivery errors in IMRT plans

Two clinical intensity modulated radiotherapy plans were selected. Eleven plan variations were created with systematic errors introduced: Multi-Leaf Collimator (MLC) positional errors with all leaf pairs shifted in the same or the opposite direction, and collimator rotation offsets. Plans were measured using an Electronic Portal Imaging Device (EPID) and an ionisation chamber array. The plans were evaluated using gamma analysis with different criteria. The gamma pass rates remained around 95% or higher for most cases with MLC positional errors of 1 mm and 2 mm with 3%/3mm criteria. The ability of both devices to detect delivery errors was similar

Maternal exposure to Δ9-tetrahydrocannabinol impairs female offspring glucose homeostasis and endocrine pancreatic development in the rat.

Recent reports indicate that 7% of pregnant mothers in North America use cannabis. This is concerning given that in utero exposure to Δ9-tetrahydrocannabinol (Δ9-THC), the main psychoactive component in cannabis, causes fetal growth restriction and may alter replication and survival of pancreatic β-cells in the offspring. Accordingly, we hypothesized that maternal exposure to Δ9-THC during pregnancy would impair postnatal glucometabolic health of offspring. To test this hypothesis, pregnant Wistar rats were treated with daily intraperitoneal injections of either 3 mg/kg Δ9-THC or vehicle from gestational day 6 to birth. Offspring were subsequently challenged with glucose and insulin at 5 months of age to assess glucose tolerance and peripheral muscle insulin sensitivity. Female offspring exposed to Δ9-THC in utero were glucose intolerant, associated with blunted insulin response in muscle and increased serum insulin concentration 15 min after glucose challenge. Additionally, pancreata from male and female offspring were harvested at postnatal day 21 and 5 months of age for assessment of endocrine pancreas morphometry by immunostaining. This analysis revealed that gestational exposure to Δ9-THC reduced the density of islets in female, but not male, offspring at postnatal day 21 and 5 months, culminating in reduced β-cell mass at 5 months. These results demonstrate that fetal exposure to Δ9-THC causes female-specific impairments in glucose homeostasis, raising concern regarding the metabolic health of offspring, particularly females, exposed to cannabis in utero

Long-Term Consequences of Fetal and Neonatal Nicotine Exposure: A Critical Review

Cigarette smoking during pregnancy is associated with numerous obstetrical, fetal, and developmental complications, as well as an increased risk of adverse health consequences in the adult offspring. Nicotine replacement therapy (NRT) has been developed as a pharmacotherapy for smoking cessation and is considered to be a safer alternative for women to smoking during pregnancy. The safety of NRT use during pregnancy has been evaluated in a limited number of short-term human trials, but there is currently no information on the long-term effects of developmental nicotine exposure in humans. However, animal studies suggest that nicotine alone may be a key chemical responsible for many of the long-term effects associated with maternal cigarette smoking on the offspring, such as impaired fertility, type 2 diabetes, obesity, hypertension, neurobehavioral defects, and respiratory dysfunction. This review will examine the long-term effects of fetal and neonatal nicotine exposure on postnatal health

Δ9-tetrahydrocannabinol exposure during rat pregnancy leads to symmetrical fetal growth restriction and labyrinth-specific vascular defects in the placenta.

1 in 5 women report cannabis use during pregnancy, with nausea cited as their primary motivation. Studies show that (-)-△9-tetrahydrocannabinol (Δ9-THC), the major psychoactive ingredient in cannabis, causes fetal growth restriction, though the mechanisms are not well understood. Given the critical role of the placenta to transfer oxygen and nutrients from mother, to the fetus, any compromise in the development of fetal-placental circulation significantly affects maternal-fetal exchange and thereby, fetal growth. The goal of this study was to examine, in rats, the impact of maternal Δ9-THC exposure on fetal development, neonatal outcomes, and placental development. Dams received a daily intraperitoneal injection (i.p.) of vehicle control or Δ9-THC (3 mg/kg) from embryonic (E)6.5 through 22. Dams were allowed to deliver normally to measure pregnancy and neonatal outcomes, with a subset sacrificed at E19.5 for placenta assessment via immunohistochemistry and qPCR. Gestational Δ9-THC exposure resulted in pups born with symmetrical fetal growth restriction, with catch up growth by post-natal day (PND)21. During pregnancy there were no changes to maternal food intake, maternal weight gain, litter size, or gestational length. E19.5 placentas from Δ9-THC-exposed pregnancies exhibited a phenotype characterized by increased labyrinth area, reduced Epcam expression (marker of labyrinth trophoblast progenitors), altered maternal blood space, decreased fetal capillary area and an increased recruitment of pericytes with greater collagen deposition, when compared to vehicle controls. Further, at E19.5 labyrinth trophoblast had reduced glucose transporter 1 (GLUT1) and glucocorticoid receptor (GR) expression in response to Δ9-THC exposure. In conclusion, maternal exposure to Δ9-THC effectively compromised fetal growth, which may be a result of the adversely affected labyrinth zone development. These findings implicate GLUT1 as a Δ9-THC target and provide a potential mechanism for the fetal growth restriction observed in women who use cannabis during pregnancy

Prenatal Exposure to Delta-9-tetrahydrocannabinol (THC) Alters the Expression of miR-122-5p and Its Target Igf1r in the Adult Rat Ovary

As cannabis use during pregnancy increases, it is important to understand its effects on the developing fetus. Particularly, the long-term effects of its psychoactive component, delta-9-tetrahydrocannabinol (THC), on the offspring’s reproductive health are not fully understood. This study examined the impact of gestational THC exposure on the miRNA profile in adult rat ovaries and the possible consequences on ovarian health. Prenatal THC exposure resulted in the differential expression of 12 out of 420 evaluated miRNAs. From the differentially expressed miRNAs, miR-122-5p, which is highly conserved among species, was the only upregulated target and had the greatest fold change. The upregulation of miR-122-5p and the downregulation of its target insulin-like growth factor 1 receptor (Igf1r) were confirmed by RT-qPCR. Prenatally THC-exposed ovaries had decreased IGF-1R-positive follicular cells and increased follicular apoptosis. Furthermore, THC decreased Igf1r expression in ovarian explants and granulosa cells after 48 h. As decreased IGF-1R has been associated with diminished ovarian health and fertility, we propose that these THC-induced changes may partially explain the altered ovarian follicle dynamics observed in THC-exposed offspring. Taken together, our data suggests that prenatal THC exposure may impact key pathways in the developing ovary, which could lead to subfertility or premature reproductive senescence