Corrigendum: Bryophyllum pinnatum compounds inhibit oxytocin-induced signaling pathways in human myometrial cells.

[This corrects the article DOI: 10.3389/fphar.2021.632986.].

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.

A Bufadienolide-Enriched Fraction of Bryophyllum pinnatum Inhibits Human Myometrial Contractility In Vitro.

Bryophyllum pinnatum has been used since the 1970s to prevent premature labour, first in anthroposophic hospitals and, more recently, also in the main Swiss perinatal centres. However, it is not known which compounds in B. pinnatum leaves contribute to the tocolytic effect. Here we studied the effects of a flavonoid-enriched fraction, the corresponding flavonoid aglycon mixture, a bufadienolide-enriched fraction, and B. pinnatum leaf press juice on human myometrial contractility in vitro. The strength (area under the curve and amplitude) and frequency of contractions were recorded using strips of human myometrium mounted in an organ bath system. Cell viability assays were performed with the human myometrium hTERT-C3 and PHM1 - 41 cell lines. Repeated addition of the flavonoid-enriched fraction, flavonoid aglycon mixture, bufadienolide-enriched fraction, or B. pinnatum leaf press juice led to a progressive decrease of contraction strength, without jeopardising the vitality of myometrium strips. The bufadienolide-enriched fraction was the most active, since 1 µg/mL of the bufadienolide-enriched fraction lowered the area under the curve to 40.1 ± 11.8% of the initial value, whereas 150 µg/mL of the flavonoid-enriched fraction, 6.2 µg/mL of the flavonoid aglycon mixture, and 10 µg/mL of the B. pinnatum leaf press juice were required to achieve comparable inhibition. A progressive increase of contraction frequency was observed, except in the case of the flavonoid aglycon mixture, which did not affect frequency. None of the test substances decreased myometrial cell viability, even at concentrations of 500 µg/mL of the flavonoid-enriched fraction, 40 µg/mL of the flavonoid aglycon mixture, 3.8 µg/mL of the bufadienolide-enriched fraction, and 75 µg/mL of the B. pinnatum leaf press juice, i.e., higher than those used in the myometrium experiments. Given the concentrations of flavonoids in the flavonoid-enriched fraction and B. pinnatum leaf press juice, and of bufadienolides in the bufadienolide-enriched fraction and B. pinnatum leaf press juice, it appears that bufadienolides may be mainly responsible for the relaxant effect.

Potential of Bryophyllum pinnatum as a Detrusor Relaxant: An in Vitro Exploratory Study.

An earlier prospective, randomised, placebo-controlled clinical trial had suggested that Bryophyllum pinnatum might have potential in the treatment of overactive bladder. Here we investigated the effects of B. pinnatum leaf press juice, fractions enriched in flavonoids and bufadienolides, and a flavonoid aglycon mixture and individual aglycons on detrusor contractility as a major target in overactive bladder treatment. The strength of the detrusor contractions was investigated using porcine muscle strips stimulated with KCl. B. pinnatum leaf press juice increased the contraction force of muscle strips. Treatment with the flavonoid-enriched fraction had almost no effect on contractility, while the bufadienolide-enriched fraction and flavonoid aglycons led to a concentration-dependent lowering of the contraction force. The data indicate that several components of B. pinnatum leaf press juice may contribute to the inhibitory effect on detrusor contractility, which in turn provides support to overactive bladder treatment with B. pinnatum.

Two new flavonol glycosides and a metabolite profile of Bryophyllum pinnatum, a phytotherapeutic used in obstetrics and gynaecology.

Bryophyllum pinnatum is a succulent perennial plant native to Madagascar which is used in anthroposophical medicine to treat psychiatric disorders and as a tocolytic agent to prevent premature labour. We performed a metabolite profiling study in order to obtain a comprehensive picture of the constituents in B. pinnatum leaves and to identify chromatographic markers for quality control and safety assessment of medicinal preparations. Preliminary HPLC-PDA-ESIMS analyses revealed that flavonoid glycosides were the main UV-absorbing constituents in the MeOH extract of B. pinnatum. Two phenolic glucosides, syringic acid ß-D-glucopyranosyl ester (1) and 4'-O-ß-D-glucopyranosyl-cis-p-coumaric acid (2), as well as nine flavonoids (3-11) including kaempferol, quercetin, myricetin, acacetin, and diosmetin glycosides were unambiguously identified by 1H and 2D NMR analysis after isolation from a MeOH extract. The flavonol glycosides quercetin 3-O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside 7-O-ß-D-glucopyranoside (3) and myricetin 3-O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside (4) were new natural products. With the aid of HPLC-PDA-APCIMS and authentic references isolated from the related species B. daigremontianum, the presence of four bufadienolides, bersaldegenin-1-acetate (12), bryophyllin A (13), bersaldegenin-3-acetate (14), and bersaldegenin-1,3,5-orthoacetate (15) was detected in B. pinnatum.

Prescribing pattern of Bryophyllum preparations among a network of anthroposophic physicians.

BACKGROUND: The use of preparations from Bryophyllum pinnatum for tocolysis (or to arrest labor) is supported by observations obtained mainly at empirical level, but also by preclinical experiments performed with uterus strips and myometrium cell lines. Furthermore, a retrospective matched-pair study revealed good tolerability and effectiveness. In anthroposophic medicine, however, Bryophyllum species are used for a broad spectrum of diagnoses. Here, we characterize the prescribing pattern of Bryophyllum preparations in a network of anthroposophic physicians in Germany. METHODS: 38 primary-care physicians in Germany participated in the EvaMed network, a multi-center observational study. They documented anonymized prescriptions, diagnoses and demographic data (age and gender) for each consecutive patient between 01.01.2004 and 01.01.2010. Diagnoses were coded according to the 10th revision of the International Classification of Diseases (ICD-10). In the present analysis, all prescriptions of any Bryophyllum preparation in the resulting data bank were identified and the corresponding diagnoses were analyzed retrospectively. RESULTS: A total of 4,038 prescriptions of Bryophyllum preparations were identified in the EvaMed data bank. A variety of preparations could be found, 77.7% of which were prepared from Bryophyllum plants exclusively and 22.5% were combinations. Bryophyllum preparations were often prescribed to treat 'mental and behavioral disorders' (ICD-10 F00-F99, 35.7%) and 'diseases of the skin and subcutaneous tissue' (L00-L99, 16.0%), followed by 'symptoms, signs, and abnormal clinical and laboratory findings, not elsewhere classified diseases' (R00-R99, 15.2%) and 'diseases of the nervous system' (G00- G99, 9.7%). CONCLUSION: By revealing the use of Bryophyllum preparations in so many other indications than preterm delivery, our data clearly show the urgent need to conduct additional clinical trials.