RESUMEN
The medicinal plant Bryophyllum pinnatum was previously shown to block oxytocin (OT)-induced signals in myometrial cells, consistent with its tocolytic effect observed in patients. OT activates not only OT receptors but also V1A receptors, two receptors with high receptor homology that are both expressed in the myometrium and play a crucial role in myometrial contraction signaling. We aimed to study the molecular pharmacology of B. pinnatum herbal preparations using specific receptor ligands, the human myometrial cell line hTERT-C3, and cell lines expressing recombinant human OT and V1A receptors.We found that press juice from B. pinnatum (BPJ) inhibits both OT- and vasopressin (AVP)-induced intracellular calcium increases in hTERT-C3 myometrial cells. In additional assays performed with cells expressing recombinant receptors, BPJ also inhibited OT and V1A receptor-mediated signals with a similar potency (IC50 about 0.5 mg/mL). We further studied endogenous OT- and AVP-sensitive receptors in hTERT-C3 cells and found that OT and AVP stimulated those receptors with similar potency (EC50 of ~ 1 nM), suggesting expression of both receptor subtypes. This interpretation was corroborated by the antagonist potencies of atosiban and relcovaptan that we found. However, using qPCR, we almost exclusively found expression of OT receptors suggesting a pharmacological difference between recombinant OT receptors and native receptors expressed in hTERT-C3 cells.In conclusion, we show that B. pinnatum inhibits both OT and AVP signaling, which may point beyond its tocolytic effects to other indications involving a disbalance in the vasopressinergic system.
Asunto(s)
Kalanchoe , Miometrio , Oxitocina , Receptores de Oxitocina , Transducción de Señal , Vasopresinas , Humanos , Oxitocina/farmacología , Femenino , Kalanchoe/química , Receptores de Oxitocina/metabolismo , Miometrio/efectos de los fármacos , Miometrio/metabolismo , Transducción de Señal/efectos de los fármacos , Vasopresinas/farmacología , Vasopresinas/metabolismo , Extractos Vegetales/farmacología , Receptores de Vasopresinas/metabolismo , Receptores de Vasopresinas/genética , Vasotocina/farmacología , Vasotocina/análogos & derivados , Línea Celular , Pirrolidinas/farmacología , Calcio/metabolismo , IndolesRESUMEN
The pregnane X receptor (PXR) is a ligand-activated regulator of cytochrome P450 (CYP)3A enzymes. Among the ligands of human PXR is hyperforin, a constituent of St John's wort (SJW) extracts and potent inducer of human CYP3A4. It was the aim of this study to compare the effect of hyperforin and SJW formulations controlled for its content on CYP3A23-3A1 in rats. Hyperiplant was used as it contains a high hyperforin content and Rebalance because it is controlled for a low hyperforin content. In silico analysis revealed a weak hyperforin-rPXR binding affinity, which was further supported in cell-based reporter gene assays showing no hyperforin-mediated reporter activation in presence of rPXR. However, cellular exposure to Hyperiplant and Rebalance transactivated the CYP3A reporter 3.8-fold and 2.8-fold, respectively, and they induced Cyp3a23-3a1 mRNA expression in rat hepatoma cells compared with control 48-fold and 18-fold, respectively. In Wistar rats treated for 10 days with 400 mg/kg of Hyperiplant, we observed 1.8 times the Cyp3a23-3a1 mRNA expression, a 2.6-fold higher CYP3A23-3A1 protein amount, and a 1.6-fold increase in activity compared with controls. For Rebalance we only observed a 1.8-fold hepatic increase of CYP3A23-3A1 protein compared with control animals. Even though there are differing effects on rCyp3a23-3a1/CYP3A23-3A1 in rat liver reflecting the hyperforin content of the SJW extracts, the modulation is most likely not linked to an interaction of hyperforin with rPXR. SIGNIFICANCE STATEMENT: Treatment with St John's wort (SJW) has been reported to affect CYP3A expression and activity in rats. Our comparative study further supports this finding but shows that the pregnane X receptor-ligand hyperforin is not the driving force for changes in rat CYP3A23-3A1 expression and function in vivo and in vitro. Importantly, CYP3A induction mimics findings in humans, but our results suggest that another so far unknown constituent of SJW is responsible for the expression- and function-modifying effects in rat liver.
Asunto(s)
Antineoplásicos , Hypericum , Ratas , Humanos , Animales , Citocromo P-450 CYP3A/metabolismo , Receptor X de Pregnano , Hypericum/metabolismo , Ligandos , Ratas Wistar , ARN Mensajero , Extractos Vegetales/farmacología , Extractos Vegetales/químicaRESUMEN
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.
Asunto(s)
Intercambio Materno-Fetal , Placenta , Embarazo , Humanos , Femenino , Espectrometría de Masas en Tándem , Perfusión/métodosRESUMEN
Herbal medication used in the treatment of sleep disorders and anxiety often contain extracts of Valeriana officinalis or Passiflora incarnata. Valerenic acid in V. officinalis and apigenin, orientin, and vitexin in P. incarnata are thought to contribute to their therapeutic effect. It was the aim of this study to test whether these constituents of herbal extracts are interacting with the uptake of estrone 3-sulfate, pregnenolone sulfate, and dehydroepiandrosterone sulfate mediated by the uptake transporters organic anion transporting polypeptide 2B1 (OATP2B1) or organic anion transporting polypeptide 1A2 (OATP1A2). Madin-Darby canine kidney cells overexpressing OATP2B1 or OATP1A2 were used to determine the influence of the constituents on the cellular accumulation of the sulfated steroids. Subsequently, competitive counterflow experiments were applied to test whether identified inhibitors are also substrates of the transporters. Valerenic acid only interacted with OATP2B1, whereas apigenin, orientin, and vitexin interacted with OATP2B1 and OATP1A2. Competitive counterflow revealed that orientin is a substrate of both transporters, while apigenin was transported by OATP1A2 and vitexin by OATP2B1. In a next step, commercially available P. incarnata preparations were assessed for their influence on the transporters, revealing inhibition of transporter-mediated estrone 3-sulfate uptake. HPLC-UV-MS analysis confirmed the presence of orientin and vitexin in these preparations, thereby suggesting that these constituents are involved in the interaction. Our data indicate that constituents of P. incarnata may alter the function of OATP2B1 and OATP1A2, which could affect the uptake of other compounds relying on uptake mediated by the transporters.
Asunto(s)
Transportadores de Anión Orgánico , Passiflora , Fitoquímicos/farmacología , Valeriana , Animales , Transporte Biológico , Perros , Transportadores de Anión Orgánico/metabolismo , Passiflora/química , Péptidos , Valeriana/químicaRESUMEN
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.
Asunto(s)
Ansiolíticos , Hypericum , Trastornos Mentales , Aceites Volátiles , Plantas Medicinales , Valeriana , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Femenino , Glucosa , Humanos , Hipnóticos y Sedantes/uso terapéutico , Lactatos , Trastornos Mentales/tratamiento farmacológico , Aceites Volátiles/farmacología , Aceites Volátiles/uso terapéutico , Fitoterapia , Placenta , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , EmbarazoRESUMEN
Corms are obtained as a byproduct during the cultivation of saffron (Crocus sativus). In a project aimed at the valorization of this waste product, we observed that a 70% EtOH extract of the corms and a sugar-depleted MeOH fraction of the extract inhibited the TNF-α/IFN-γ-induced secretion and gene expression of the chemokines IL-8, MCP-1, and RANTES in human HaCaT cells. The effects were in part stronger than those of the positive control hydrocortisone. For preparative isolation, the 70% EtOH extract was partitioned between n-BuOH and water. Separation of the n-BuOH-soluble fraction by centrifugal partition chromatography, followed by preparative and semipreparative HPLC, afforded a series of bidesmosidic glycosides of echinocystic acid bearing a 3,16-dihydroxy-10-oxo-hexadecanoic acid residue attached to the glycosidic moiety at C-28. They include azafrines 1 and 2, previously reported in saffron, and eight new congeners named azafrines 3-10. Saffron saponins significantly inhibited TNF-α/IFN-γ-induced secretion of RANTES in human HaCaT cells at 1 µM (p < 0.001). Some of them further lowered TNF-α/IFN-γ-induced gene expression.
Asunto(s)
Crocus/química , Citocinas , Saponinas/farmacología , Quimiocina CCL5 , Citocinas/metabolismo , Expresión Génica/efectos de los fármacos , Células HaCaT , Humanos , Interferón gamma , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Saponinas/aislamiento & purificación , Factor de Necrosis Tumoral alfaRESUMEN
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.
Asunto(s)
Intercambio Materno-Fetal , Placenta , Benzofenantridinas , Alcaloides de Berberina , Ciclohexenos , Humanos , Técnicas In Vitro , Perfusión , Embarazo , Espectrometría de Masas en Tándem , TerpenosRESUMEN
A blinded placebo-controlled multi-center on-farm trial was conducted in dairy cows with subclinical ketosis to investigate effects of a multicomponent herbal extract. Blood ketone levels were measured weekly in early lactating cows from 16 Swiss herds. Cows were subclassified based on their initial blood-ß-hydroxybutyrate levels (≥ 1.0 [KET-low, 84 cows] and > 1.2 mmol/L [KET-high, 39 cows]) and randomly distributed to 3 groups treated orally with herbal extract containing Camellia sinensis, Cichcorium intybus, Gentiana lutea, Glycyrrhiza glabra, Taraxacum officinale, Trigonella foenum-graecum, and Zingiber officinale, sodium propionate, or placebo twice a day for 5 days. Milk yield, milk acetone, blood-ß-hydroxybutyrate, glucose, nonesterified fatty acids, gamma-glutamyl transferase, and glutamate dehydrogenase were analyzed over 2 wk. Linear mixed effect models were used for data analysis. No effects were found for nonesterifed fatty acids, gamma-glutamyl transferase, and glucose. Significantly higher glutamate dehydrogenase (29.71 U/L) values were found in herbal extract-treated animals compared to sodium propionate on day 7 (22.33 U/L). By trend, higher blood-ß-hydroxybutyrate levels (1.36 mmol/L) were found in the placebo group of KET-high-cows on day 14 compared to the sodium propionate group (0.91 mmol/L). Milk yields of all treatment groups increased. Milking time and treatment showed a significant interaction for milk acetone: sodium propionate led to an immediate decrease, whereas herbal extracts resulted in a milk acetone decrease from day 7 on, reaching significantly lower milk acetone on day 14 (3.17 mg/L) when compared to placebo (4.89 mg/L). In conclusion, herbal extracts and sodium propionate are both likely to improve subclinical ketosis in dairy cows, however, by different modes of action.
Asunto(s)
Enfermedades de los Bovinos , Cetosis , Extractos Vegetales , Ácido 3-Hidroxibutírico , Animales , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Femenino , Cetosis/tratamiento farmacológico , Cetosis/veterinaria , Lactancia , Extractos Vegetales/farmacologíaRESUMEN
In contrast to natural and historical diets of wild and domesticated ruminants, the diversity of plant species is limited in diets of modern dairy cows. Are "production diseases" linked to this? We conducted a trial to test the effects of a multicomponent herbal feed additive (HFA) on health, performance and fertility traits. A dose-finding study (DF) with 62 cows on 11 commercial farms compared a low (50 g) and a high (100 g) dose of HFA (HFA-50, HFA-100) with a placebo (PL). In a subsequent field trial (FT) with 280 cows on 30 commercial farms, HFA-100 was compared to PL. Cows were randomly assigned to HFA and PL groups and received HFA or PL individually daily from 14 days pre- to 300 days post-calving. Data were analysed with mixed effects models. No differences between HFA and PL were found regarding performance, body condition score and overall culling rates. A tendency towards lower milk urea for HFA-100 compared to PL (p = .06) was found in DF. HFA significantly reduced elevated milk acetone observations (≥10 mg/L) in the first 10 lactation weeks (HFA-100: 4%; HFA-50: 4%; PL: 12%) in DF. HFA-50 significantly reduced lameness incidence (HFA-100: 11%; HFA-50: 2%; PL: 14%) in DF. Calving intervals were 15 days shorter in HFA compared to PL in both trials, which could be confirmed by tendency (p = .07) in FT. In both trials, the proportion of test days with elevated somatic cell score (≥3.0) was significantly lower in HFA compared to PL (DF: HFA-100: 40%, HFA-50: 45% and PL: 55%; FT: HFA-100: 38% and PL: 55%) which is also reflected by tendency (p = .08) in lower culling rates due to udder diseases in FT. HFA showed no negative impact on any of the measured parameters. The effects of HFA indicate a potential of phytochemically rich and diverse feed additives for dairy cows' nutrition and physiology.
Asunto(s)
Alimentación Animal/análisis , Bovinos , Suplementos Dietéticos , Leche/citología , Fitoquímicos/farmacología , Sacrificio de Animales , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Reducción Gradual de Medicamentos , Femenino , Lactancia , Fitoquímicos/administración & dosificación , FitoterapiaRESUMEN
The herbal remedy St. John's wort (SJW) is used in the treatment of mild depressive symptoms and is known for its drug-drug interaction potential when enhanced expression of CYP3A4 modifies clearance of concomitantly applied substrate drugs. Hyperforin is one constituent of SJW that alters CYP3A4 expression by activation of the nuclear receptor pregnane X receptor (PXR). However, little is known about the transmembrane transport of hyperforin. One membrane protein that modulates cellular entry of drugs is the organic anion-transporting polypeptide (OATP) 2B1. It was the aim of this study to test whether hyperforin interacts with this transport protein. Transport inhibition studies and competitive counterflow experiments suggested that hyperforin is a substrate of OATP2B1. This notion was validated by showing that the presence of OATP2B1 enhanced the hyperforin-induced PXR activation in cell-based luciferase assays. Moreover, in Caco-2 cells transcellular transport of the known OATP2B1 substrate atorvastatin was changed in the presence of hyperforin, resulting in an increased efflux ratio. Eleven commercially available SJW formulations were assessed for their influence on OATP2B1-mediated transport of estrone 3-sulfate and for their impact on CYP3A4 promoter transactivation. The correlation between effect size and the hyperforin content as determined by high-performance liquid chromatography with ultraviolet detection suggested that hyperforin is the major determinant. Our results indicate an interaction between hyperforin and OATP2B1, which is not only known to contribute to hepatocellular uptake but also to intestinal absorption of its substrates. These findings extend the complexity of mechanisms that should be considered when evaluating the interaction potential of SJW preparations.
Asunto(s)
Transportadores de Anión Orgánico/metabolismo , Floroglucinol/análogos & derivados , Receptor X de Pregnano/metabolismo , Terpenos/farmacología , Transporte Biológico/efectos de los fármacos , Células CACO-2 , Línea Celular Tumoral , Citocromo P-450 CYP3A/metabolismo , Interacciones Farmacológicas/fisiología , Estrona/análogos & derivados , Estrona/metabolismo , Células HeLa , Células Hep G2 , Humanos , Absorción Intestinal/efectos de los fármacos , Floroglucinol/farmacología , Regiones Promotoras Genéticas/efectos de los fármacosRESUMEN
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 PHM1â-â41 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.
Asunto(s)
Bufanólidos/farmacología , Flavonoides/farmacología , Kalanchoe/química , Bufanólidos/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Femenino , Flavonoides/aislamiento & purificación , Humanos , Contracción Muscular/efectos de los fármacos , Miometrio/efectos de los fármacos , Miometrio/metabolismo , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Hojas de la Planta/químicaRESUMEN
Fractionation of the n-hexane extract of Salvia hydrangea afforded seven isoprenoids including six new compounds (1-6) and salvadione A (7). Their structures were established by comprehensive spectroscopic and spectrometric data analysis (1D and 2D NMR, HRMS). The absolute configuration of salvadione A (7) was established by single-crystal X-ray diffraction analysis with Cu/Kα radiation. In addition, the absolute configuration of all compounds was determined by electronic circular dichroism spectroscopy. A biosynthetic pathway for the formation of the scaffold of 1 is proposed. The antiprotozoal activity of the compounds against Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani, and Plasmodium falciparum was determined, and cytotoxicity was assessed in rat myoblast L6 cells. Perovskone C (2) exhibited good activity against P. falciparum (IC50 0.6 µM) and a selectivity index of 62.2.
Asunto(s)
Antiprotozoarios/aislamiento & purificación , Salvia/química , Terpenos/aislamiento & purificación , Animales , Antiprotozoarios/química , Antiprotozoarios/farmacología , Línea Celular , Leishmania donovani/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Plasmodium falciparum/efectos de los fármacos , Ratas , Análisis Espectral , Terpenos/química , Terpenos/farmacología , Trypanosoma brucei rhodesiense/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacosRESUMEN
Equisetum arvense, known as common horsetail, is used for the treatment of inflammatory diseases and is the plant with the highest concentration of silica. Yet it is unknown if the medicinal properties are mediated by its silica content. In the current study, optimal conditions for silica-rich horsetail preparations were identified. Bioactivity of the preparations was analyzed in vitro using flow cytometry-based activity and functionality profiling of primary human lymphocytes as well as cytokine measurement using a classical ELISA technique. Experiments revealed that horsetail preparations suppress activation and proliferation of lymphocytes by an interleukin-2-dependent mechanism. The effect increased with the silica concentration in the decoctions. Lymphocytes' polyfunctionality was also influenced, shown by a downregulation of IFN-γ. Analytical profiling by HPLC-UV-MS and bioactivity testing revealed relevant immunosuppressive concentrations of a component that has been identified as isoquercitrin. Our results show that both silica and isoquercitrin are active compounds of horsetail preparations.
Asunto(s)
Antiinflamatorios/farmacología , Equisetum/química , Preparaciones de Plantas/farmacología , Quercetina/análogos & derivados , Dióxido de Silicio/farmacología , Antiinflamatorios/química , Cromatografía Líquida de Alta Presión , Humanos , Linfocitos/efectos de los fármacos , Preparaciones de Plantas/química , Quercetina/química , Quercetina/aislamiento & purificación , Quercetina/farmacología , Dióxido de Silicio/químicaRESUMEN
As part of a screening for new antiparasitic natural products from Iranian plants, n-hexane and ethyl acetate extracts from the aerial parts of Perovskia abrotanoides were found to exhibit strong inhibitory activity against Trypanosoma brucei rhodesiense and Leishmania donovani. The activity was tracked by high-performance liquid chromatography (HPLC)-based activity profiling. Preparative isolation by a combination of silica gel column chromatography and HPLC afforded 17 diterpenoids (1: -17: ), including 14 abietane-, two icetexane-, and one isopimarane-type derivatives. Among these, (5R,10S)-11-hydroxy-12-methoxy-20-norabieta-8,11,13-triene (2: ), 12-hydroxy-norabieta-1(10),8,11,13-tetraene-1,11-furan (6: ), and 12-methoxybarbatusol (9: ) were new compounds, the structure of which was established by comprehensive spectroscopic data analysis (one- and two-dimensional nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, electronic circular dichroism). The antiprotozoal activity of the isolated compounds was evaluated against T.âb. rhodesiense, Trypanosoma cruzi, L. donovani, and Plasmodium falciparum. Selectivity indexes (SI) were calculated in comparison to cytotoxicity on rat myoblast (L6) cells. Particularly active were 7α-ethoxyrosmanol (4: ) with an IC50 of 0.8 µM against T.âb. rhodesiense (SI 14.9) and an IC50 of 1.8 µM (SI 6.9) against L. donovani, ferruginol (8: ) with an IC50 of 2.9 µM (SI 19.2) against P. falciparum, and miltiodiol (10: ) with an IC50 of 0.5 µM (SI 10.5) against T.âb. rhodesiense. None of the compounds exhibited selective toxicity against T. cruzi (SI ≤ 1.6).
Asunto(s)
Antiprotozoarios/farmacología , Diterpenos/farmacología , Lamiaceae/química , Leishmania donovani/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos , Animales , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Diterpenos/química , Diterpenos/aislamiento & purificación , Mioblastos/efectos de los fármacos , Componentes Aéreos de las Plantas/química , RatasRESUMEN
Myotonic dystrophy type I (DM1) is a disabling neuromuscular disease with no causal treatment available. This disease is caused by expanded CTG trinucleotide repeats in the 3' UTR of the dystrophia myotonica protein kinase gene. On the RNA level, expanded (CUG)n repeats form hairpin structures that sequester splicing factors such as muscleblind-like 1 (MBNL1). Lack of available MBNL1 leads to misregulated alternative splicing of many target pre-mRNAs, leading to the multisystemic symptoms in DM1. Many studies aiming to identify small molecules that target the (CUG)n-MBNL1 complex focused on synthetic molecules. In an effort to identify new small molecules that liberate sequestered MBNL1 from (CUG)n RNA, we focused specifically on small molecules of natural origin. Natural products remain an important source for drugs and play a significant role in providing novel leads and pharmacophores for medicinal chemistry. In a new DM1 mechanism-based biochemical assay, we screened a collection of isolated natural compounds and a library of over 2100 extracts from plants and fungal strains. HPLC-based activity profiling in combination with spectroscopic methods were used to identify the active principles in the extracts. The bioactivity of the identified compounds was investigated in a human cell model and in a mouse model of DM1. We identified several alkaloids, including the ß-carboline harmine and the isoquinoline berberine, that ameliorated certain aspects of the DM1 pathology in these models. Alkaloids as a compound class may have potential for drug discovery in other RNA-mediated diseases.
Asunto(s)
Regiones no Traducidas 3' , Alcaloides/farmacología , Proteínas de Unión al ADN , Modelos Biológicos , Distrofia Miotónica/tratamiento farmacológico , Proteínas de Unión al ARN , Expansión de Repetición de Trinucleótido , Alcaloides/química , Alcaloides/aislamiento & purificación , Empalme Alternativo/efectos de los fármacos , Animales , Línea Celular , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Humanos , Ratones , Distrofia Miotónica/genética , Distrofia Miotónica/metabolismo , Distrofia Miotónica/patología , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismoRESUMEN
An in-house library of more than 3000 extracts of plant and fungal origin was screened against some major plant pathogens. As one of the hits, an ethyl acetate extract from inflorescences of Verbesina lanata showed significant inhibitory activity in vitro against grapevine downy mildew (Plasmopara viticola), with a MIC100 value of 35 µg/mL. An emulsifiable concentrate formulation with 50 mg/g of the extract was developed for in vivo evaluation. A suspension of the formulation containing 1 mg/mL of extract lowered leaf surface infection of grapevine seedling by 82% compared to the nontreated control. With the aid of HPLC-based activity profiling, the antifungal activity was correlated with a series of lipophilic compounds. Preparative isolation by a combination of chromatographic techniques afforded 16 eudesmane sesquiterpenes including eight new congeners. Nine compounds were obtained in sufficient quantities to be tested in vitro and were found to inhibit the zoospore activity of P. viticola with MIC100 values ranging from 4 to 50 µg/mL. The two major compounds, 6ß-cinnamoyloxy-4ß,9ß,15-trihydroxyeudesmane (9) and 6ß-cinnamoyloxy-1ß,15-dihydroxyeudesm-4-en-3-one (13), showed MIC100 values of 5 and 31 µg/mL, respectively.
RESUMEN
Phenolic constituents of Salix reticulata (Salicaceae) and antiproliferative activity of an extract and individual compounds were investigated in immortalized human non-tumorigenic keratinocytes (HaCaT). A MeOH extract from aerial parts afforded several flavonoids, including luteolin and apigenin glycosides (2-5 and 9) and catechin (1), two procyanidin fractions, and the phenolic glucosides picein (6), triandrin (7), and salicortin (8). In an adenosine triphosphate assay, the MeOH extract reduced cell viability by approximately 60â% at a concentration of 100 µg/mL. Cell proliferation was assessed with a BrdU incorporation ELISA assay. The extract inhibited proliferation of HaCaT cells in a concentration-dependent manner, with approximately 50â% inhibition at 100 µg/mL. In time-lapse assays, the extract showed distinct inhibitory effects on cell migration at concentrations of 12.5, 25, and 50 µg/mL. The activity of selected constituents was also determined. Luteolin-7-O-ß-glucuronide (3) significantly inhibited cell proliferation at concentrations of 10 and 50 µM. In contrast, luteolin-7-O-ß-glucopyranoside (2) and a procyanidin fraction (P1) had only weak effects, while picein (6) and salicortin (8) did not affect cell proliferation. Luteolin-7-O-ß-glucuronide (10 µM) and, to a lesser extent, the procyanidin fraction (10 µg/mL) also inhibited cell migration.
Asunto(s)
Glicósidos/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , Salix/química , Proliferación Celular/efectos de los fármacos , Flavonas/metabolismo , Glucurónidos/metabolismo , Glicósidos/aislamiento & purificación , Humanos , Queratinocitos/efectos de los fármacos , Componentes Aéreos de las Plantas/química , Extractos Vegetales/aislamiento & purificación , Proantocianidinas/metabolismoRESUMEN
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.
Asunto(s)
Kalanchoe , Extractos Vegetales/uso terapéutico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Animales , Bufanólidos/uso terapéutico , Femenino , Flavonoides/uso terapéutico , Técnicas In Vitro , Kalanchoe/química , Masculino , Relajación Muscular/efectos de los fármacos , PorcinosRESUMEN
The hawthorn (Crataegus spp.) extract WS 1442 is used against mild forms of chronic heart failure. This disease is associated with endothelial barrier dysfunction and edema formation. We have recently shown that WS 1442 protects against this dysfunction by a dual mechanism: it both promotes endothelial barrier integrity by activation of a barrier-enhancing pathway (cortactin activation) and inhibits endothelial hyperpermeability by blocking a barrier disruptive pathway (calcium signaling). In this study, we aimed to identify the bioactive compounds responsible for these actions by using a bioactivity-guided fractionation approach. From the four fractions generated from WS 1442 by successive elution with water, 95â% ethanol, methanol, and 70â% acetone, only the water fraction was inactive, whereas the other three triggered a reduction of endothelial hyperpermeability. Analyses of intracellular calcium levels and cortactin phosphorylation were used as readouts to estimate the bioactivity of subfractions and isolated compounds. Interestingly, only the ethanolic fraction interfered with the calcium signaling, whereas only the methanolic fraction led to an activation of cortactin. Thus, the dual mode of action of WS 1442 could be clearly assigned to two distinct fractions. Although the identification of the calcium-active substance(s) was not successful, we could exclude an involvement of phenolic compounds. Cortactin activation, however, could be clearly attributed to oligomeric procyanidins with a distinct degree of polymerization. Taken together, our study provides the first approach to identify the active constituents of WS 1442 that address different cellular pathways leading to the inhibition of endothelial barrier dysfunction.
Asunto(s)
Edema/prevención & control , Flavonoides/farmacología , Extractos Vegetales/farmacología , Calcio/metabolismo , Células Cultivadas , Fraccionamiento Químico , Crataegus/química , Endotelio Vascular/efectos de los fármacos , Flavonoides/química , Células Endoteliales de la Vena Umbilical Humana , Humanos , Extractos Vegetales/químicaRESUMEN
Bryophyllum pinnatum (syn. Kalanchoe pinnata) is a succulent perennial plant native to Madagascar that was introduced in anthroposophic medicine in the early 20th century. In recent years, we conducted a large collaborative project to provide reliable data on the chemical composition, pharmacological properties, and clinical efficacy of Bryophyllum. Here, we comprehensively review the phytochemistry, as well as the pharmacological and clinical data. As to the pharmacology, special emphasis is given to properties related to the use in anthroposophic medicine as a treatment for "hyperactivity diseases", such as preterm labor, restlessness, and sleep disorders. Studies suggesting that B. pinnatum may become a new treatment option for overactive bladder syndrome are also reviewed. Tolerability is addressed, and toxicological data are discussed in conjunction with the presence of potentially toxic bufadienolides in Bryophyllum species. The few data available on two related species with medicinal uses, Bryophyllum daigremontianum and Bryophyllum delagoense, have also been included. Taken together, current data support the use of B. pinnatum for the mentioned indications, but further studies are needed to fully understand the modes of action, and to identify the pharmacologically active constituents.