Transplacental passage of hyperforin, hypericin, and valerenic acid

Safe medications for mild mental diseases in pregnancy are needed. Phytomedicines from St. John’s wort and valerian are valid candidates, but safety data in pregnancy are lacking. The transplacental transport of hyperforin and hypericin (from St. John’s wort), and valerenic acid (from valerian) was evaluated using the ex vivo cotyledon perfusion model (4 h perfusions, term placentae) and, in part, the in vitro Transwell assay with BeWo b30 cells. Antipyrine was used for comparison in both models. U(H)PLC-MS/MS bioanalytical methods were developed to quantify the compounds. Perfusion data obtained with term placentae showed that only minor amounts of hyperforin passed into the fetal circuit, while hypericin did not cross the placental barrier and valerenic acid equilibrated between the maternal and fetal compartments. None of the investigated compounds affected metabolic, functional, and histopathological parameters of the placenta during the perfusion experiments. Data from the Transwell model suggested that valerenic acid does not cross the placental cell layer. Taken together, our data suggest that throughout the pregnancy the potential fetal exposure to hypericin and hyperforin – but not to valerenic acid – is likely to be minimal.

Placental Passage of Protopine in an Ex Vivo Human Perfusion System

The placental passage of protopine was investigated with a human ex vivo placental perfusion model. The model was first validated with diazepam and citalopram, 2 compounds known to cross the placental barrier, and antipyrine as a positive control. All compounds were quantified by partially validated U(H)PLC-MS/MS bioanalytical methods. Protopine was transferred from the maternal to the fetal circuit, with a steady-state reached after 90 min. The study compound did not affect placental viability or functionality, as glucose consumption, lactate production, and beta-human chorionic gonadotropin, and leptin release remained constant. Histopathological evaluation of all placental specimens showed unremarkable, age-appropriate parenchymal maturation with no pathologic findings.

Medicinal Plants for the Treatment of Mental Diseases in Pregnancy: An In Vitro Safety Assessment

Pregnancy is a critical period for medical care, during which the well-being of woman and fetus must be considered. This is particularly relevant in managing non-psychotic mental disorders since treatment with central nervous system-active drugs and untreated NMDs may have negative effects. Some well-known herbal preparations (phytopharmaceuticals), including St. John's wort, California poppy, valerian, lavender, and hops, possess antidepressant, sedative, anxiolytic, or antidepressant properties and could be used to treat mental diseases such as depression, restlessness, and anxiety in pregnancy. Our goal was to assess their safety in vitro, focusing on cytotoxicity, induction of apoptosis, genotoxicity, and effects on metabolic properties and differentiation in cells widely used as a placental cell model (BeWo b30 placenta choriocarcinoma cells). The lavender essential oil was inconspicuous in all experiments and showed no detrimental effects. At low-to-high concentrations, no extract markedly affected the chosen safety parameters. At an artificially high concentration of 100 µg/mL, extracts from St. John's wort, California poppy, valerian, and hops had minimal cytotoxic effects. None of the extracts resulted in genotoxic effects or altered glucose consumption or lactate production, nor did they induce or inhibit BeWo b30 cell differentiation. This study suggests that all tested preparations from St. John's wort, California poppy, valerian, lavender, and hops, in concentrations up to 30 µg/mL, do not possess any cytotoxic or genotoxic potential and do not compromise placental cell viability, metabolic activity, and differentiation. Empirical and clinical studies during pregnancy are needed to support these in vitro data.

Advanced in Vitro Safety Assessment of Herbal Medicines for the Treatment of Non-Psychotic Mental Disorders in Pregnancy

When confronted with non-psychotic mental disorders, pregnant women often refrain from using synthetic drugs and resort to herbal medicines such as St. John’s wort, California poppy, valerian, lavender, and hops. Nevertheless, these herbal medicines have not yet been officially approved in pregnancy due to lack of safety data. Using a variety of in vitro methods (determination of cytotoxicity, apoptosis induction, genotoxicity, effects on metabolic properties, and inhibition/induction of differentiation) in a commonly used placental cell line (BeWo b30), we were previously able to show that extracts from these plants are likely to be safe at the usual clinical doses. In the present work, we wanted to extend our safety assessment of these herbal medicines by 1) looking for possible effects on gene expression and 2) using the same in vitro methods to characterize effects of selected phytochemicals that might conceivably lead to safety issues. Proteomics results were promising, as none of the five extracts significantly affected protein expression by up- or down-regulation. Protopine (contained in California poppy), valerenic acid (in valerian), and linalool (in lavender) were inconspicuous in all experiments and showed no adverse effects. Hyperforin and hypericin (two constituents of St. John’s wort) and valtrate (typical for valerian) were the most obvious phytochemicals with respect to cytotoxic and apoptotic effects. A decrease in cell viability was evident with hypericin (≥1 µM) and valtrate (≥10 µM), whereas hyperforin (≥3 µM), hypericin (30 µM) and valtrate (≥10 µM) induced cell apoptosis. None of the tested phytochemicals resulted in genotoxic effects at concentrations of 0.1 and 1 µM and thus are not DNA damaging. No decrease in glucose consumption or lactate production was observed under the influence of the phytochemicals, except for valtrate (at all concentrations). No compound affected cell differentiation, except for hyperforin (≥1 µM), which had an inhibitory effect. This study suggests that extracts from St. John’s wort, California poppy, valerian, lavender, and hops are likely to be safe during pregnancy. High plasma concentrations of some relevant compounds—hyperforin and hypericin from St. John’s wort and valtrate from valerian—deserve special attention, however.

Placental Passage of Humulone and Protopine in an Ex Vivo Human Perfusion System

The placental passage of humulone and protopine was investigated with a human ex vivo placental perfusion model. The model was first validated with diazepam and citalopram, 2 compounds known to cross the placental barrier, and antipyrine as a positive control. All compounds were quantified by partially validated U(H)PLC-MS/MS bioanalytical methods. Only a small portion of humulone initially present in the maternal circuit reached the fetal circuit. The humulone concentration in the maternal circuit rapidly decreased, likely due to metabolization in the placenta. Protopine was transferred from the maternal to the fetal circuit, with a steady-state reached after 90 min. None of the study compounds affected placental viability or functionality, as glucose consumption, lactate production, beta-human chorionic gonadotropin, and leptin release remained constant. Histopathological evaluation of all placental specimens showed unremarkable, age-appropriate parenchymal maturation with no pathologic findings.

Use of Herbal Medicines for the Treatment of Mild Mental Disorders and/or Symptoms During Pregnancy: A Cross-Sectional Survey

Little is known about the treatment of mild mental disorders and/or symptoms (MDS) during pregnancy. Our main purpose was to compare the use of herbal medicines during pregnancy in women with and without MDS. A questionnaire consisting of 21 multiple-choice questions was distributed in the participating obstetrics clinics or birth centers in the Canton of Zurich, in Switzerland, from August 2018 to March 2019; 398 questionnaires were considered in the analysis. The use of any type of herbal medicines-including pharmaceutical herbal products as well as teas-during pregnancy was reported by 358 women (out of 398, 89.9%). Of these, 272 participants used pharmaceutical herbal products, whereby ginger (49.2%), raspberry leaf (42.7%), bryophyllum (37.8%), chamomile (27.2%), lavender (22%) and iron-rich herbs (12.3%) were the ones most commonly mentioned. More than half (207/398, 52.0%) of all participants reported suffering from MDS during pregnancy; only a few took (synthetic) psychoactive medications (5/398, 1.3%). The percentage of use of pharmaceutical herbal medicines was higher among women reporting MDS than among the remaining women (90.0 vs 75.9%; p < 0.001). At the same time, the prevalence of MDS was higher among users of pharmaceutical herbal products than among non-users (59.6 vs 34.0%; p = 0.001). Specific questions on candidate herbal medicines for the treatment of mild MDS revealed that bryophyllum (mentioned by 107 women), lavender (56 women) and valerian (20 women) were used to reduce stress, restlessness, sleep disorders and others, in part with perceived good to very good effectiveness and tolerability. The large majority of the pregnant women participating in the survey make use of herbal medicines. The particularly high prevalence of MDS among herbal medicine-users and the very rare use of synthetic psychoactive medications suggest that pregnant women rely on herbal medicines for treatment of mild MDS. The reported good effectiveness and tolerability of a few candidate herbal medicines deserve particular attention.

Nalbuphine: a candidate for treatment of women overwhelmed with sudden, intense labor pain?

AIM

On very rare occasions, women are overwhelmed with sudden, intense labor pain in the context of ultra-rapid late second stage of labor, especially when the head is crowning. The consequences may comprise serious pelvic floor damage for the mother and hypoxia for the fetus. Drugs like nalbuphine for immediate maternal analgesia and sedation would be helpful. This mixed opioid agonist-antagonist, that was used in obstetric anesthesia in the 1980s, acts quickly while side effects for the mother are minor. To better estimate possible complications for the fetus of a use shortly before birth, it is important to find out how quickly i.v. administered nalbuphine reaches fetal circulation. Therefore, we characterized the transplacental transfer of nalbuphine using an ex vivo model.

METHODS

Placentas were obtained from cesarean sections after mothers gave their informed consent. Upon cannulation of one cotyledon, nalbuphine was added to the maternal circuit (calculated final concentration 100 ng/mL) and the ex vivo placenta perfusions were performed. To determine nalbuphine transfer from maternal to fetal circuit in the successful perfusions (n = 5), samples were collected at different time points.

RESULTS

At perfusion start, the measured initial nalbuphine concentrations in the maternal and fetal circuits are 93.1 and <0.1 ng/mL, respectively. After 5 min of placenta perfusion, 2.5 ng/mL nalbuphine (i.e. 3% of the initial nalbuphine concentration in the maternal circuit) is reached in the fetal circuit; after 15 and 30 min, 9.7 and 15.8 ng/mL (approximately 10 and 16% of initial maternal, respectively).

CONCLUSIONS

Only a small amount of nalbuphine is likely to reach the fetus during the first minutes after (i.v.) maternal administration. Nalbuphine might be a valuable candidate for clinical use in the i.v. analgesia and sedation of women overwhelmed with sudden labor pain in the context of ultra-rapid second stage of labor.

Influence of osmolarity and hydration on the tear resistance of the human amniotic membrane

The amnion is considered to be the load-bearing part of the fetal membranes. We investigated the influence of osmolarity of the testing medium and hydration on its fracture toughness. Mode I fracture tests revealed that physiological variations in the bath osmolarity do not influence the tear resistance of amnion, while larger changes, i.e. from physiological saline solution to distilled water, lead to a significant reduction of the fracture toughness. Uniaxial tensile tests on collagen hydrogels confirmed the reduction in toughness, suggesting that lower bath osmolarity triggers changes in the failure properties of single collagen fibers. Prenatal surgeries, in particular fetoscopic procedures with partial amniotic carbon dioxide insufflation, might result in dehydration of the amnion. Dehydration induced a brittle behavior; however, subsequent rehydration for 15 min resulted in a similar tear resistance as for the fresh tissue.

On the defect tolerance of fetal membranes

A series of mechanical experiments were performed to quantify the strength and fracture toughness of human amnion and chorion. The experiments were complemented with computational investigations using a 'hybrid' model that includes an explicit representation of the collagen fibre network of amnion. Despite its much smaller thickness, amnion is shown to be stiffer, stronger and tougher than chorion, and thus to determine the mechanical response of fetal membranes, with respect to both, deformation and fracture behaviour. Data from uniaxial tension and fracture tests were used to inform and validate the computational model, which was then applied to rationalize measurements of the tear resistance of tissue samples containing crack-like defects. Experiments and computations show that the strength of amnion is not significantly reduced by defects smaller than 1 mm, but the crack size induced by perforations for amniocentesis and fetal membrane suturing during fetal surgery might be larger than this value. In line with previous experimental observations, the computational model predicts a very narrow near field at the crack tip of amnion, due to localized fibre alignment and collagen compaction. This mechanism shields the tissue from the defect and strongly reduces the interaction of multiple adjacent cracks. These findings were confirmed through corresponding experiments, showing that no interaction is expected for multiple sutures for an inter-suture distance larger than 1 mm and 3 mm for amnion and chorion, respectively. The experimental procedures and numerical models applied in the present study might be used to optimize needle and/or staple dimensions and inter-suture distance, and thus to reduce the risk of iatrogenic preterm premature rupture of the membranes from amniocentesis, fetoscopic and open prenatal surgery.

Individual variations in the fibrinolytic response during and after cardiopulmonary bypass

The purpose of this study was to determine whether individual patients show different patterns of fibrinolytic response to cardiopulmonary bypass (CPB) and whether preoperative or intraoperative parameters were predictive of these different patterns. Active t-PA, active PAI-1 and total t-PA antigen were measured in plasma samples obtained from 38 subjects, age 32 to 85 (median 69 years), before, during and after CPB. Four patterns of fibrinolytic response were noted: 1) 40% of patients showed the "typical" response, a rapid rise in active and total t-PA during CPB followed postoperatively by elevated PAI-1 and reduced t-PA, 2) 10% showed no change in t-PA or PAI-1 during or after CPB, 3) 24% showed no change in t-PA with an increase in PAI-1 postoperatively, and 4) 26% showed an increase in t-PA during CPB with no change in PAI-1 postoperatively. When present, the t-PA response was rapid, occurring within the first 30 min of CPB and was more common in patients undergoing valve surgery than in coronary artery bypass grafting (p < 0.005). Increased levels of PAI-1 postoperatively were associated with ischemic times greater than 70 min (p = 0.003) but not with the total length of CPB. Age, sex, CPB temperature, total CPB time and preoperative levels of t-PA and PAI-1 were not associated in the intra- or postoperative fibrinolytic response pattern. We conclude that the fibrinolytic response to CPB is heterogeneous. Further studies will be needed to determine whether different response patterns are clinically significant.