Cigarette smoking alters sialylation in the Fallopian tube of women, with implications for the pathogenesis of ectopic pregnancy

Mechanism of Human Tubal Ectopic Pregnancy Caused by Cigarette Smoking

In the past few decades, the smoking rate of women of childbearing age has increased. Epidemiological data has repeatedly shown that smoking women have an increased risk of various reproductive diseases, including ectopic pregnancy (EP), decreased fertility, adverse pregnancy outcomes, and failure of assisted reproduction. The oviduct was the target of cigarette smoke in many in vivo and in vitro studies. The fallopian tube is a well-designed organ. Its function is to collect and transport the ova to the fertilized site and provide a suitable environment for fertilization and early embryonic development. Lastly, the fallopian tube transports the pre-implantation embryo to the uterus. Various biological processes can be studied in the fallopian tubes, making it an excellent model for toxicology. This paper reviews the roles of the fallopian tube in gametes and embryo transportation, and the possible mechanism tobacco smoke contributes to tubal EP. A possible signal pathway might be a model to develop intervention of EP for pregnant women exposed to smoking.

ST6GAL1 and α2-6 Sialylation Regulates IL-6 Expression and Secretion in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a systemic disease strongly associated with cigarette smoking, airway inflammation, and acute disease exacerbations. Changes in terminal sialylation and fucosylation of asparagine (N)-linked glycans have been documented in COPD, but the role that glycosyltransferases may play in the regulation of N-linked glycans in COPD has not been fully elucidated. Recent studies suggest that modulation of ST6GAL1 (ST6 beta-galactoside alpha-2,6-sialyltransferase-1), which catalyzes terminal α2-6 sialylation of cellular proteins, may regulate inflammation and contribute to COPD phenotype(s). Interestingly, it has been previously demonstrated that ST6GAL1, a Golgi resident protein, can be proteolytically processed by BACE1 (beta-site amyloid precursor protein cleaving enzyme-1) to a circulating form that retains activity. In this study, we showed that loss of ST6GAL1 expression increased interleukin (IL)-6 expression and secretion in human bronchial epithelial cells (HBECs). Furthermore, exposure to cigarette smoke medium/extract (CSE) or BACE1 inhibition resulted in decreased ST6GAL1 secretion, reduced α2-6 sialylation, and increased IL-6 production in HBECs. Analysis of plasma ST6GAL1 levels in a small COPD patient cohort demonstrated an inverse association with prospective acute exacerbations of COPD (AECOPD), while IL-6 was positively associated. Altogether, these results suggest that reduced ST6GAL1 and α2-6 sialylation augments IL-6 expression/secretion in HBECs and is associated with poor clinical outcomes in COPD.

Setting priorities in the conventional approaches in managing ectopic pregnancy; is it time to reform? A teaching hospital experience

THE AIM OF THE STUDY

To review the management approaches of ectopic pregnancy (EP) at the Department of Obstetrics and Gynecology at Jordan University Hospital (JUH).

MATERIAL AND METHODS

All patients admitted to our department with the diagnosis of EP treated during the study period extending from January 2017 to June 2019. Data were collected retrospectively using the patients' files anonymously. Main outcome measures: age, parity, ectopic site, presentation, the main risk factor/s and the management plan.

RESULTS

In total, 65 cases of EP were managed during the study period. Overall, the mean age was 30 years. EP was located in the right tube in 23 cases, and in the left tube in 14 cases. Eleven patients presented with acute abdomen due to rupture of the EP and underwent urgent laparotomy; 7 of these cases were located on the right side. Conservative surgery (laparoscopy versus laparotomy) was the main line of management with attention to preserving the tube patency, followed by medical therapy when the patient fulfilled the criteria or those with pregnancy of unknown location.

CONCLUSIONS

EP is a life-threatening condition. It is time to reform the priorities in the conventional approach to management. Every effort ought to be applied to preserve the reproductivity of women who are diagnosed with EP at the JUH. We would suggest that salpingostomy needs to be considered the surgical treatment of choice for the majority of these cases.

Tubal flushing with oil- or water-based contrast medium: can we identify markers that indicate treatment benefit?

STUDY QUESTION

Can we identify patient characteristics that distinguish which ovulatory infertile women undergoing hysterosalpingography (HSG) benefit more or less from flushing with oil-based contrast medium compared to water-based contrast medium?

SUMMARY ANSWER

In ovulatory infertile women, HSG with oil-based contrast medium resulted in higher 6-month ongoing pregnancy and live birth rates as compared to HSG with water-based contrast medium and this treatment effect was independent of characteristics of the couple.

WHAT IS KNOWN ALREADY

We recently showed that in infertile women undergoing HSG, flushing with oil-based contrast medium resulted in more ongoing pregnancies than flushing with water-based contrast medium.

STUDY DESIGN, SIZE, DURATION

We used data from our randomized clinical trial (RCT) in which 1,119 ovulatory infertile women undergoing HSG during fertility work-up were randomized for use of oil-based (N = 557) or water-based (N = 562) contrast medium.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We built logistic regression models to predict ongoing pregnancy and live birth (secondary outcome) as a function of the specific contrast, the specific marker, and marker-by-contrast-interaction. Markers considered were female age, maternal ethnicity, female smoking, body mass index (BMI), duration of infertility, infertility being primary or secondary, sperm quality, and previous appendectomy.

MAIN RESULTS AND THE ROLE OF CHANCE

The 6-month ongoing pregnancy rates in the overall population were 39.7% after use of oil-based contrast versus 29.1% after use of water-based contrast medium [relative risk (RR), 1.37; 95% confidence interval (CI), 1.16–1.61; P < 0.001]. Among the studied baseline characteristics, BMI (P = 0.002) and semen volume (P = 0.02) were statistically significant prognosticators. The treatment effect of oil-based contrast was stronger in women with a BMI ≤30 kg/m² [RR, 1.54; 95% CI, 1.23–1.92; P = 0.002], and in women whose partner had a semen volume >3 ml [RR, 1.77; 95% CI, 1.28–2.46; P = 0.02]. Also, in women who smoked, the treatment effect of flushing with oil was stronger, but this interaction did not reach statistical significance (P = 0.066). We found no positive effect of oil-based contrast in obese women. We found similar but weaker associations for live birth, which was probably due to lower number of events resulting in less power.

LIMITATIONS, REASONS FOR CAUTION

The RCT was restricted to infertile ovulatory women younger than 39 years of age without endocrinological disorders and at low risk for tubal pathology. Our results should not be generalized to infertile women who do not share these features.

WIDER IMPLICATIONS OF THE FINDINGS

All infertile, ovulatory women younger than 39 years with a low risk for tubal pathology will benefit from an HSG with oil-based contrast; therefore, this should be offered to them after fertility work-up.

STUDY FUNDING/COMPETING INTEREST(S)

The original H2Oil RCT was an investigator-initiated study that was funded by the two academic institutions (AMC and VUmc) of the Amsterdam UMC. The study displayed in this paper was funded by an unconditional research grant from Guerbet. B.W.M. is supported by an NHMRC Practitioner Fellowship (GNT1082548). K.D. reports consultancy for Guerbet, during the conduct of the study, and also reports research grants from Guerbet. C.B.L. reports grants from Guerbet, during the conduct of the study, and grants from Ferring, grants from Merck, and personal fees from Ferring, outside the submitted work. P.H. reports grants from Guerbet, during the conduct of the study, and grants from Ferring and Merck, outside the submitted work. V.M. reports receiving travel and speakers fee as well as research grants from Guerbet. B.W.M. reports consultancy for ObsEva, Merck, Merck KGaA, and Guerbet, and research grants from Guerbet and Merck. The other authors have no conflict of interest to declare.

TRIAL REGISTRATION NUMBER

NTR 3270 www.trialregister.nl

TRIAL REGISTRATION DATE

1 February 2012.

DATE OF FIRST PATIENT’S ENROLMENT

3 February 2012.

Chronic fetal hypoxia disrupts the peri-conceptual environment in next-generation adult female rats

KEY POINTS

Exposure to chronic hypoxia during gestation influences long-term health and development, including reproductive capacity, across generations. If the peri-conceptual environment in the developing oviduct is affected by gestational hypoxia, then this could have implications for later fertility and the health of future generations. In the present study, we show that the oviducts of female rats exposed to chronic hypoxia in utero have reduced telomere length, decreased mitochondrial DNA biogenesis and increased oxidative stress The results of the present study show that exposure to chronic gestational hypoxia leads to accelerated ageing of the oviduct in early adulthood and they help us understand how exposure to hypoxia during development could influence reproductive health across generations.

ABSTRACT

Exposure to chronic hypoxia during fetal development has important effects on immediate and long-term outcomes in offspring. Adverse impacts in adult offspring include impairment of cardiovascular function, metabolic derangement and accelerated ovarian ageing. However, it is not known whether other aspects of the female reproductive system may be similarly affected. In the present study, we examined the impact of chronic gestational hypoxia on the developing oviduct. Wistar rat dams were randomized to either normoxia (21%) or hypoxia (13%) from day 6 post-mating until delivery. Post-delivery female offspring were maintained in normoxia until 4 months of age. Oviductal gene expression was assayed at the RNA (quantitative RT-PCR) and protein (western blotting) levels. Oviductal telomere length was assayed using Southern blotting. Oviductal telomere length was reduced in the gestational hypoxia-exposed animals compared to normoxic controls (P < 0.01). This was associated with a specific post-transcriptional reduction in the KU70 subunit of DNA-pk in the gestational hypoxia-exposed group (P < 0.05). Gestational hypoxia-exposed oviducts also showed evidence of decreased mitochondrial DNA biogenesis, reduced mtDNA copy number (P < 0.05) and reduced gene expression of Tfam (P < 0.05) and Pgc1α (P < 0.05). In the hypoxia-exposed oviducts, there was upregulation of mitochondrial-specific anti-oxidant defence enzymes (MnSOD; P < 0.01). Exposure to chronic gestational hypoxia leads to accelerated ageing of the oviduct in adulthood. The oviduct plays a central role in early development as the site of gamete transport, syngamy, and early development; hence, accelerated ageing of the oviductal environment could have important implications for fertility and the health of future generations.

Influence of Active Exposure to Tobacco Smoke on Nitric Oxide Status of Pregnant Women

Smoking tobacco can impair proper vascular endothelial functioning. This is exhibited through reduced nitric oxide synthesis as well as activity due to accompanying oxidative stress. We examined the relationship between nitric oxide and markers of oxidative stress/antioxidant defense in serum of smoking and non-smoking pregnant women. Subjects included 99 healthy pregnant women, who were tested for nitric oxide (NO), endothelial (eNOS) and inducible (iNOS) nitric oxide synthase, total oxidant capacity (TOC), and total antioxidant capacity (TAC). NO, eNOS, and TAC serum concentrations were significantly lower (p < 0.005), but iNOS (p < 0.05) and TOC (p < 0.001) were higher in smokers than in non-smokers. Multivariate regression analysis showed associations between NO concentration and eNOS, TAC, and smoking status in the whole group of patients. In the model estimated separately for smokers, the highest impact of eNOS (β = 0.375; p = 0.021) and cotinine (β = −0.323; p = 0.037) was indicated for NO concentration. In the model of non-smokers, eNOS (β = 0.291, p = 0.030) and TAC (β = 0.350; p = 0.015) were important for NO level. Smoking during pregnancy could exacerbate oxidative stress, impair the action of nitric oxide synthases, and adversely affect the balance of oxygen and nitrogen metabolism. Relationships between NO concentrations and TAC in the studied women’s blood can confirm the antioxidant nature of nitric oxide.

Retroperitoneal ectopic pregnancy: a case report and review of the literature

Background

Retroperitoneal ectopic pregnancy (REP) is an extremely rare type of ectopic pregnancy, with a total of less than 20 cases reported in the English literature. However, failure to recognize REP may result in severe consequences.

Case presentation

We report a case of 32-year-old woman with REP. She had amenorrhea, left lower abdominal pain, but no vaginal bleeding. Her urine human chorionic gonadotropin (HCG) test was positive and blood HCG level was 1880 m-international units per milliliter (mIU/mL). Transvaginal ultrasound sonography showed a left adnexal mass. Laparoscopy found an enlarged uterus, normal right uterine tube and ovary, and normal left uterine tube. The left ovary was partly covered by a blood clot, but appeared normal after removing the clot. There was a 10-mm circular peritoneal defect located lateral to the left sacrocervical ligament, anterior to the left ovarian fossa, and next to the lower edge of the left broad ligament. The patient was diagnosed of having REP with the gestational tissues covered by the peritoneum. The REP was removed by laparoscopic surgery. Bleeding was stopped by bipolar coagulation and absorbable hemostatic cellulose. The patient recovered smoothly and was discharged on the next day after surgery. Her blood HCG returned to normal range 29 days after surgery.

Conclusions

REP is very rare, but in any suspected case of ectopic pregnancy, caution must be paid to find signs of REP when the common sites of ectopic pregnancy do not have any positive findings.