Bryophyllum pinnatum enhances the inhibitory effect of atosiban and nifedipine on human myometrial contractility: an in vitro study

Repurposing of Bryophyllum pinnatum for dysmenorrhea treatment: a systematic scoping review and case series

Dysmenorrhea affects women throughout their reproductive years but there has been a lack of effective and well-tolerated treatment options. Pain symptoms mainly result from inflammatory processes and increased contractile activity in the myometrium. The reported use of Bryophyllum pinnatum preparations against inflammation and pain in ethnomedicine as well as current pharmacological data on their inhibition of myometrial contractility led us to hypothesize that this medicinal plant might be a new treatment option for dysmenorrhea. In the first part of the present work, clinical, in vivo, and in vitro studies on the anti-nociceptive and anti-inflammatory, as well as on myometrium relaxing properties of B. pinnatum are reviewed. In the second part, cases of five women with dysmenorrhea who were tentatively treated with a B. pinnatum product are described. The review revealed thirty-three experimental in vivo and in vitro studies, but no clinical study, reporting anti-nociceptive and anti-inflammatory effects of B. pinnatum extracts and compounds in a wide range of conditions. Moreover, sixteen publications on smooth muscle contractility revealed relaxing effects. The latter consisted of clinical evidence, as well as of in vivo and in vitro data. The evidence reviewed therefore provided a rational basis for the use of B. pinnatum in the treatment of dysmenorrhea. We subsequently set out to tentatively treat patients with a well-tolerated B. pinnatum product that is registered (without indication) and commonly used in obstetrics and gynecology in Switzerland. All five treated patients reported a reduction in pain symptoms and 4 out of 5 indicated a reduced intake of painkillers during menstruation. Taken together, the reviewed information on the pharmacological properties and clinical evidence of B. pinnatum extracts and compounds as well as the outcomes of all five patients in the case series support our hypothesis in favor of B. pinnatum as a new, well-tolerated therapeutic approach for dysmenorrhea. Prospective clinical studies are urgently needed.

Regulation of oxytocin-induced calcium transients and gene expression in engineered myometrial tissues by tissue architecture and matrix rigidity

The uterus is susceptible to benign tumors known as fibroids, which have been associated with many pregnancy complications, including preterm labor. However, the impact of fibrotic tissue remodeling on the physiology of the myometrium, the smooth muscle layer of the uterus, is poorly understood, in large part due to a lack of model systems. In this study, we engineered healthy-like and fibrotic-like myometrium by culturing human myometrial smooth muscle cells on polyacrylamide hydrogels micropatterned with fibronectin to independently tune matrix rigidity and tissue alignment, respectively. We then evaluated calcium transients in response to oxytocin stimulation. Isotropic myometrial tissues on stiff substrates (representing fibrotic myometrium) had shorter calcium transients due to shorter decay time compared to aligned myometrial tissues on soft substrates (representing healthy myometrium). Calcium transients in aligned tissues had longer response times and longer decay times than isotropic tissues, irrespective of substrate stiffness. The amplitude of calcium transients was also higher on soft substrates compared to stiff substrates, irrespective of tissue alignment. We also performed RNA sequencing to detect differentially expressed genes between healthy- and fibrotic-like tissues, which revealed that a bitter taste receptor shown to induce smooth muscle relaxation, TAS2R31, was down-regulated in fibrotic-like tissues. Finally, we measured oxytocin-induced calcium transients in response to pre-treatment with progesterone, caffeine, thrombin, and nifedipine to demonstrate applications for our model system in drug screening. Both progesterone and caffeine caused a decrease in calcium transient duration, as expected, while thrombin and nifedipine had less impact. Collectively, our engineered model of the myometrium enables new insights into myometrial mechanobiology and can be extended to identify or screen novel drug targets.

Arrest of mouse preterm labor until term delivery by combination therapy with atosiban and mundulone, a natural product with tocolytic efficacy

There is a lack of FDA-approved tocolytics for the management of preterm labor (PL). In prior drug discovery efforts, we identified mundulone and mundulone acetate (MA) as inhibitors of in vitro intracellular Ca2+-regulated myometrial contractility. In this study, we probed the tocolytic potential of these compounds using human myometrial samples and a mouse model of preterm birth. In a phenotypic assay, mundulone displayed greater efficacy, while MA showed greater potency and uterine-selectivity in the inhibition of intracellular-Ca2+ mobilization. Cell viability assays revealed that MA was significantly less cytotoxic. Organ bath and vessel myography studies showed that only mundulone exerted inhibition of myometrial contractions and that neither compounds affected vasoreactivity of ductus arteriosus. A high-throughput combination screen identified that mundulone exhibits synergism with two clinical-tocolytics (atosiban and nifedipine), and MA displayed synergistic efficacy with nifedipine. Of these combinations, mundulone+atosiban demonstrated a significant improvement in the in vitro therapeutic index compared to mundulone alone. The ex vivo and in vivo synergism of mundulone+atosiban was substantiated, yielding greater tocolytic efficacy and potency on myometrial tissue and reduced preterm birth rates in a mouse model of PL compared to each single agent. Treatment with mundulone after mifepristone administration dose-dependently delayed the timing of delivery. Importantly, mundulone+atosiban permitted long-term management of PL, allowing 71% dams to deliver viable pups at term (>day 19, 4-5 days post-mifepristone exposure) without visible maternal and fetal consequences. Collectively, these studies provide a strong foundation for the development of mundulone as a single or combination tocolytic for management of PL.

Arrest of mouse preterm labor until term delivery by combination therapy with atosiban and mundulone, a natural product with tocolytic efficacy

Currently, there is a lack of FDA-approved tocolytics for the management of preterm labor (PL). In prior drug discovery efforts, we identified mundulone and its analog mundulone acetate (MA) as inhibitors of in vitro intracellular Ca 2+ -regulated myometrial contractility. In this study, we probed the tocolytic and therapeutic potential of these small molecules using myometrial cells and tissues obtained from patients receiving cesarean deliveries, as well as a mouse model of PL resulting in preterm birth. In a phenotypic assay, mundulone displayed greater efficacy in the inhibition of intracellular-Ca 2+ from myometrial cells; however, MA showed greater potency and uterine-selectivity, based IC 50 and E max values between myometrial cells compared to aorta vascular smooth muscle cells, a major maternal off-target site of current tocolytics. Cell viability assays revealed that MA was significantly less cytotoxic. Organ bath and vessel myography studies showed that only mundulone exerted concentration-dependent inhibition of ex vivo myometrial contractions and that neither mundulone or MA affected vasoreactivity of ductus arteriosus, a major fetal off-target of current tocolytics. A high-throughput combination screen of in vitro intracellular Ca 2+ -mobilization identified that mundulone exhibits synergism with two clinical-tocolytics (atosiban and nifedipine), and MA displayed synergistic efficacy with nifedipine. Of these synergistic combinations, mundulone + atosiban demonstrated a favorable in vitro therapeutic index (TI)=10, a substantial improvement compared to TI=0.8 for mundulone alone. The ex vivo and in vivo synergism of mundulone and atosiban was substantiated, yielding greater tocolytic efficacy and potency on isolated mouse and human myometrial tissue and reduced preterm birth rates in a mouse model of PL compared to each single agent. Treatment with mundulone 5hrs after mifepristone administration (and PL induction) dose-dependently delayed the timing of delivery. Importantly, mundulone in combination with atosiban (FR 3.7:1, 6.5mg/kg + 1.75mg/kg) permitted long-term management of PL after induction with 30 μg mifepristone, allowing 71% dams to deliver viable pups at term (> day 19, 4-5 days post-mifepristone exposure) without any visible maternal and fetal consequences. Collectively, these studies provide a strong foundation for the future development of mundulone as a stand-alone single- and/or combination-tocolytic therapy for management of PL.

Bioactive Compounds from Kalanchoe Genus Potentially Useful for the Development of New Drugs

The genus Kalanchoe Adans. (Crassulaceae) is native to Madagascar and comprises 145 species, being naturalized in the tropics and cultivated worldwide. In addition to having ornamental value, several Kalanchoe species are commonly used in popular medicine for the treatment of inflammatory conditions, wounds, gastric ulcers, and other diseases. The great importance of the genus is reflected on its acknowledgment by traditional and alternative health systems and organizations, as well as on the growing number of papers reporting pharmacological properties of extracts and isolated compounds from Kalanchoe. Among these properties, we highlight anti-inflammatory, antitumor, wound healing, antiulcer, and muscle relaxing properties. These activities are attributed mostly to flavonoids and bufadienolides, the main secondary metabolites reported in Kalanchoe extracts. While bufadienolides are generally related to cytotoxic and muscle relaxing activities, flavonoids are commonly reported as anti-inflammatory and wound healing agents. This review provides up to date information and perspectives on bioactive compounds from the Kalanchoe genus that are potentially useful for the development of new drugs. It includes not only a discussion on the advantages of the Kalanchoe species as source of bioactive compounds, but also the gaps, opportunities, and challenges to translate the acquired knowledge into innovation for drug development.

Effects of Bryophyllum pinnatum Administration on Wistar Rat Pregnancy: Biochemical and Histological Aspects

INTRODUCTION

Bryophyllum pinnatum is widely used in folk medicine. It has neuropharmacological, anti-inflammatory, immunomodulatory, antidiabetic, hepatoprotective, and nephroprotective effects, among others. It also acts on uterine contractility. It is prescribed by practitioners of anthroposophic medicine for preterm labor, insomnia, and emotional disorders, and has other potential uses in obstetrics. As all drugs currently used in preterm labor have side effects, new tocolytic agents remain an area of active research.

OBJECTIVE

To evaluate the effect of B. pinnatum mother tincture (MT) on albino rats and their offspring throughout pregnancy from a biochemical and histological standpoint.

METHODS

Longitudinal, prospective, randomized controlled bioassay. This is the second stage of a trial that investigated 60 animals distributed across six equal groups: controls C1 and C2, which received 1 and 25 times the vehicle dose (30% ethanol), B1 and B2 (1- and 25-fold doses of B. pinnatum MT), and B3 and B4 (which received 50- and 100-fold doses of B. pinnatum concentrate). At this stage, blood chemistry parameters (glucose, alanine aminotransferase [ALT], aspartate aminotransferase [AST], creatinine, and blood urea nitrogen) were measured in dams, as well as histological aspects of dam liver, kidney, placenta, and uterine tissue and fetal liver, kidney, heart, and brain.

RESULTS

No differences were found between group B1 (therapeutic dose) and its control C1 in relation to glucose, AST, ALT, and creatinine. Group B2 exhibited lower glucose levels than groups C1, B3, and B4. There was no difference in AST across groups. Groups B3 and B4 exhibited higher ALT levels than groups C1 and B1. Groups B1-B4 exhibited higher urea nitrogen levels than group C1. Creatinine levels were higher in groups B2 and B3 than group C1. On morphological evaluation, fatty infiltration of the liver was observed in the alcoholic vehicle control groups (C1 and C2).

CONCLUSIONS

Daily administration of B. pinnatum at therapeutic doses (group B1) to pregnant albino rats appears to be safe, with reduced glucose at dose B2, elevated ALT at doses B3 and B4, and increased urea at doses B1 to B4 and creatinine at B2 and B3, but never exceeding the normal reference range. It was not associated with histological changes in specimens of the maternal or fetal structures of interest.

Bryophyllum pinnatum Compounds Inhibit Oxytocin-Induced Signaling Pathways in Human Myometrial Cells

Bryophyllum pinnatum has been used in the treatment of premature labor, first in anthroposophic hospitals and, recently, in conventional settings as an add-on medication. In vitro work with hTERT human myometrial cells showed that B. pinnatum leaf press juice inhibits the increase of intracellular free calcium concentration induced by oxytocin, a hormone known to play a role in labor. Our aim was to identify fractions/compounds in B. pinnatum press juice that contribute to this inhibitory effect, and to investigate their effect on oxytocin-driven activation of the MAPK cascade. Several fractions/compounds from B. pinnatum press juice led to a concentration-dependent decrease of oxytocin-induced increase of intracellular free calcium concentration, but none of them was as strong as B. pinnatum press juice. However, the combination of a bufadienolide and a flavonoid-enriched fraction was as effective as B. pinnatum press juice, and their combination had a synergistic effect. B. pinnatum press juice inhibited oxytocin-driven activation of MAPKs SAPK/JNK and ERK1/2, an effect also exerted by the bufadienolide-enriched fraction. The effect of B. pinnatum press juice on oxytocin-induced signaling pathways was comparable to that of the oxytocin-receptor antagonist and tocolytic agent atosiban. Our findings further substantiate the use of B. pinnatum press juice preparations in the treatment of preterm labor.

Phytotherapy in obstetrics - therapeutic indications, limits, and dangers

The wide access to varied, attractive, and aggressively promoted information can induce pregnant women to think that any form of complementary therapy can be a saving solution for a medical problem because these therapies are natural, therefore, harmless. Updated information from literature about indications, benefits, limits, and risks of phytotherapy in pregnancy was presented. Valuable therapeutic resources with proven clinical efficacy (evidence-based medicine) were presented for each trimester of pregnancy, during labor, postpartum, but also during breastfeeding. For some phytotherapeutics, there are scientific studies. There is also a detailed presentation about some possibilities for therapeutic errors, which should be avoided during pregnancy. Positive results of phytotherapy deserve to be known and applied by the obstetrician for the certain benefit of future mothers.