Development and validation of a micellar electrokinetic chromatography method for quantitative determination of butenolides in Piper malacophyllum (C. Presl) C. DC

Involvement of a neutrophil-mast cell axis in the effects of Piper malacophyllum (C. PESL) C. DC extract and its isolated compounds in a mouse model of dysmenorrhoea

The effects of Piper malacophyllum (C. Pesl) C. DC extracts and its isolated compounds were analysed in a mouse model of primary dysmenorrhoea (PD). Female Swiss mice (6-8 weeks old) on proestrus were intraperitoneally treated with estradiol benzoate for 3 days, to induce PD. Twenty-four hours later, animals were treated 24 h later with vehicle, plant extract, gibbilimbol B, 4,6-dimethoxy-5-E-phenylbutenolide, mixture of 4,6-dimethoxy-5-E-phenylbutenolide and 4,6-dimethoxy-5-Z-phenylbutenolide, or ibuprofen. One hour later, oxytocin was injected and the numbers of abdominal writhing were counted. Then, mice were euthanized and uteri were collected for morphometrical and histological analyses. The effects of P. malacophyllum in inflammation were investigated in mouse peritoneal neutrophils culture stimulated with LPS or fMLP (chemotaxis and mediator release). Finally, uterus contractile and relaxing responses were assessed. Similar to ibuprofen, P. malacophyllum extract and isolated compounds reduced abdominal writhing in mice with PD. Histology indicated a marked neutrophil and mast cell infiltrate in the uterus of PD animals which was attenuated by the extract. The compounds and the extract reduced neutrophil chemotaxis and inflammatory mediator release by these cells. Reduced TNF levels were also observed in uteri of PD mice treated with P. malacophyllum. The extract did not affect spontaneous uterine contractions nor those induced by carbachol or KCl. However, it caused relaxation of oxytocin-induced uterine contraction, an effect blunted by H1 receptor antagonist. Overall the results indicate that P. malacophyllum may represent interesting natural tools for reliving PD symptoms, reducing the triad of pain, inflammation and spasmodic uterus behaviour.

Simultaneous separation and determination of four active ingredients in Picria fel-terrae Lour. and its preparations by micellar electrokinetic chromatography

INTRODUCTION

Picfeltarraenins IA, IB and IV and acteoside are the four bioactive ingredients of Picria fel-terrae Lour. Their pharmacological effects include central inhibitory, cardiovascular, anti-inflammatory, anti-pyretic, analgesic, anti-bacterial, antioxidative and anti-tumor effects.

OBJECTIVE

We aimed to develop an efficient micellar electrokinetic chromatography (MEKC) method modified with mixed organic solvents for the simultaneous separation and determination of the four components in Picriae Herba and its formulations.

METHODS

Method optimization was carried out by investigating influences of significant factors on the separation, and this method was successfully applied for the determination of the four components in Picriae Herba and its formulations.

RESULTS

The optimal running buffer was composed of 20 mM sodium tetraborate, 40 mM sodium cholate, 10% (v/v) methanol and 10% (v/v) isopropanol (pH 9.76). The separation voltage was 18 kV, the temperature was 25°C and the detection wavelength was 266 nm. Under the optimal separation conditions, the baseline separation of four components was achieved in less than 14 min. The correlation coefficients of the calibration curves were 0.9984-0.9995 for the analytes. The intraday and interday precision ranged from 1.5% to 2.5% and from 1.4% to 5.0%, respectively. Recoveries of analytes varied from 96.6% to 104.1%.

CONCLUSION

The method was proved suitable for the determination of four components in Picriae Herba and its formulations. Good performance was obtained under optimal conditions, and the method provides an effective tool for the quality control of Picriae Herba and its formulations.

Leishmanicidal activity of an alkenylphenol from Piper malacophyllum is related to plasma membrane disruption

Leishmaniasis and Chagas disease are parasitic protozoan infections that affect the poorest population in the world, causing high mortality and morbidity. As a result of highly toxic and long-duration treatments, novel, safe and more efficacious drugs are essential. In this work, the methanol (MeOH) extract from the leaves of Piper malacophyllum (Piperaceae) was fractioned to afford one alkenylphenol, which was characterized as 4-[(3'E)-decenyl]phenol (gibbilimbol B) by spectroscopic methods. Anti-protozoan in vitro assays demonstrated for the first time that Leishmania (L.) infantum chagasi was susceptible to gibbilimbol B, with an in vitro EC(50) of 23 μg/mL against axenic promastigotes and an EC(50) of 22 μg/mL against intracellular amastigotes. Gibbilimbol B was also tested for anti-trypanosomal activity (Trypanosoma cruzi) and showed an EC(50) value of 17 μg/mL against trypomastigotes. To evaluate the cytotoxic parameters, this alkenylphenol was tested in vitro against NCTC cells, showing a CC(50) of 59 μg/mL and absent hemolytic activity at the highest concentration of 75 μg/mL. Using the fluorescent probe SYTOX Green suggested that the alkenylphenol disrupted the Leishmania plasma membrane upon initial incubation. Further drug design studies aiming at derivatives could be a promising tool for the development of new therapeutic agents for leishmaniasis and Chagas disease.