Stellera chamaejasme and Its Main Compound Luteolin 7-O-Glucoside Alleviates Skin Lesions in Oxazolone- and 2,4-Dinitrochlorobenzene-Stimulated Murine Models of Atopic Dermatitis

Stellera chamaejasme, also known as "Langdu", has been traditionally used for the management of skin-related diseases such as psoriasis and skin ulcers. The aim of this study was to determine whether S. chamaejasme and its major component, luteolin 7-O-glucoside, have a preventive effect on the development of atopic dermatitis in oxazolone-treated BALB/c mice and 2,4-dinitrochlorobenzene-treated hairless mice. The epicutaneous applications of oxazolone and 2,4-dinitrochlorobenzene evoke an experimental murine atopic dermatitis-like reaction in BALB/c mouse ears and SKH-1 hairless mice. Atopic skin symptoms, including erythema (redness), pruritus (itching), exudation (weeping), excoriation (peeling), and lichenification (skin thickening), responded to treatment with S. chamaejasme aerial parts EtOH extract for 2 or 3 weeks. Histopathological examination revealed S. chamaejasme aerial parts EtOH extract significantly reduced inflammatory cell infiltration when applied to atopic dermatitis mice. In addition, luteolin 7-O-glucoside, the major active compound of the S. chamaejasme aerial parts EtOH extract, decreased serum IgE and IL-4 levels and transepidermal water loss and increased skin hydration, therefore exhibiting strong anti-atopic dermatitis activity in 2,4-dinitrochlorobenzene-induced atopic dermatitis mice. In this study, we confirmed antipruritic and antidermatitic effects of S. chamaejasme extract and its main component luteolin 7-O-glucoside in atopic dermatitis murine models. The study shows S. chamaejasme aerial parts EtOH extract and luteolin 7-O-glucoside are most likely to be potential drug candidates for atopic dermatitis treatment.

Effects of Lecythis pisonis Camb. (Lecythidaceae) in a mouse model of pruritus

ETHNOPHARMACOLOGICAL RELEVANCE

Lecythis pisonis Camb. (Lecythidaceae), is popularly known as "Sapucaia". In traditional medicine, leaves are used for the treatment of pruritus.

AIM OF THE STUDY

The present study is aimed to investigate the antipruritic effect of the ethanol extract from leaves of Lecythis pisonis (LPEE), fractions (hexane-LPHF, ether-LPEF and ethyl acetate-LPEAF) and mixture of triterpenes [ursolic and oleanolic acids (MT)] in mice and rats.

MATERIALS AND METHODS

The LPEE, LPHF, LPEF, LPEAF and MT were evaluated on scratching behavior induced by compound 48/80 in mice. In addition, LPEE, LPEF and MT were investigated on rat peritoneal mast cells degranulation induced by compound 48/80 (ex vivo study). The anti-inflammatory activity of LPEE and LPEF was investigated in rats using carrageenan-induced hind paw edema model. In the evaluation of the spontaneous motor activity, the LPEE was studied for its effect on spontaneous motor activity in an open-field test in mice.

RESULTS

The scratching behavior induced by compound 48/80 was significantly inhibited in mice pretreated with LPEE, LPHF, LPEF, LPEAF and MT. The suppressive effect of LPEE, LPEF and MT was only partially antagonized by naloxone. In addition, the compound 48/80-elicited degranulation of rat peritoneal mast cells was also markedly reduced in animals pretreated with LPEE, LPEF and MT. In the anti-inflammatory test, LPEE decreased the paw edema at the third hour after carrageenan (Carr) administration. Moreover, LPEF also was able to inhibit the oedematogenic response evoked by carr at all analysed time points. In the open-field test, LPEE-pretreated mice showed no impairment of spontaneous locomotion. Furthermore, the LPEE demonstrated no overt toxicity up to an oral dose of 2g/kg in an acute toxicity assay.

CONCLUSIONS

These results clearly indicate the antipruritic effects of Lecythis pisonis leaves and suggest that this effect may be related to a stabilizing action on mast cell membrane. Furthermore, these data support the traditional use of this plant against cutaneous pruritus.

Antipruritic and antiinflammatory effects of aqueous extract from Si-Wu-Tang

Si-Wu-Tang (SWT), a traditional Chinese formula, has been clinically used in the treatment of cutaneous pruritus, chronic inflammation, and other diseases. The present study was carried out to observe the antipruritic and antiinflammatory effects of SWT aqueous extract using compound 48/80 and picryl chloride (PC) models in mice. SWT (500, 1000 mg/kg p.o.) clearly reduced the scratching responses elicited by compound 48/80 in normal mice. At doses of 250 and 500 mg/kg, it inhibited the scratching responses induced by PC in mice actively sensitized with 2,4-dinitrophenol (DNP)-ovalbumin (OVA) plus alum. Furthermore, SWT (250, 500, 1000 mg/kg) significantly inhibited the footpad swelling caused by compound 48/80 in mice. In the biphasic ear skin reactions induced by PC in actively sensitized mice, SWT (250, 500 mg/kg) reduced the immediate-phase reaction, but did not affect the late-phase reaction. In vitro, SWT (50-500 microg/ml) showed a concentration-dependent inhibition of the histamine release induced by compound 48/80 from rat peritoneal mast cells. The crude drugs contained in SWT, Paeoniae Radix (25, 100 microg/ml), Rehmanniae Radix, and Chuanxiong Rhizoma (100 microg/ml), also showed a clear inhibition, but Angelica Radix did not at the concentrations examined. These findings indicate that SWT aqueous extract has antipruritic and antiinflammatory effects in mice. SWT inhibits histamine release from rat mast cells, and Paeoniae Radix probably plays a crucial role in the formula.

Antipruritic and antinociceptive effects of Chenopodium album L in mice

The ethanolic extract from the fruits of Chenopodium album L. (FCAL), orally administered at doses of 100-400 mg/kg, dose-dependently inhibited scratching behavior induced by 5-HT (10 micro g per mouse, s.c.) or compound 48/80 (50 micro g per mouse, s.c.) in mice. But it failed to affect hind paw swelling induced by 5-HT or compound 48/80 in mice at doses of 100 and 200 mg/kg and only showed a relatively weak inhibition on the swelling at a higher dose of 400 mg/kg. In addition, FCAL (200 and 400 mg/kg) significantly attenuated the writhing responses induced by an intraperitoneal injection of acetic acid and the inflammatory pain response induced by an intraplantar injection of formalin in mice. At a dose of 400 mg/kg, it also inhibited the neurogenic pain response of formalin test. In conclusion, FCAL possesses antipruritic and antinociceptive activities and the antinociceptive effects are not secondary to anti-inflammatory effects. The findings support evidence for the clinical use of FCAL to treat cutaneous pruritus.

Schizonepeta tenuifolia: chemistry, pharmacology, and clinical applications

This article presents an up-to-date review of the plant Schizonepeta tenuifolia (Jingjie), of family Labiatae, with respect to its traditional uses, chemical constituents, various pharmacological activities, and clinical effects. Nonetheless, its mechanism of actions, adverse effects, drug interactions, and contraindications remain unclear. With the global growth on the use of herbal products, Jingjie has been commonly marketed for the treatment of common cold and fever in Chinese proprietary medicines. Hence, further studies will be warranted to show its efficacy and safety.

Comparative study on camphor enantiomers behavior under the conditions of gas-liquid chromatography and reversed-phase high-performance liquid chromatography systems modified with alpha- and beta-cyclodextrins

The dependence of retention and selectivity parameters of camphor enantiomers on the concentration of alpha- and beta-cyclodextrins were studied under conditions of GLC (matrix solvent: Glycerol, 95 degrees C) and RP-HPLC (matrix solvent: Aqueous methanolic, 20 degrees C). It has been found that beta-cyclodextrin forms complex of 1:1 stoichiometry and does not recognize enantiomers of camphor. In contrast alpha-CD forming complexes of 1:2 stoichiometry appeared to be very efficient chiral selector of (+) and (-)-camphor. Relatively considerable differences have been observed between stability constants determined by GLC and RP-HPLC, what may be explained by the various natures of the matrix solvents and the various temperatures of the measurements. On the contrary, the enantioseparation factor alpha observed at higher concentrations of alpha-cyclodextrin stabilizes on the very similar value alpha+/-(GLC) approximately = alpha-/+(HPLC) approximately = 1.6. Simple theoretical considerations focusing on the differences in the mechanisms of the studied processes have been performed. According to them the enantiomer forming the more stable complex with the cyclodextrin should be eluted from the RP-HPLC column first and GLC column last. This fact has been confirmed experimentally.

Antipruritic dinaphthofuran-7,12-dione derivatives from the pericarp of Impatiens balsamina

Dinaphthofuran-7,12-dione derivatives named balsaminones A (1) and B (2) were isolated from the pericarp of Impatiens balsamina L. together with the known compound 2-methoxy-1,4-naphthoquinone (3). Their structures were elucidated by spectral techniques. These compounds have significant antipruritic activity.

[Studies on Kochiae Fructus. I. Antipruritogenic effect of 70% ethanol extract from kochiae fructus and its active component]

The antipruritogenic effect of the 70% ethanol extract obtained from Kochiae Fructus (fruits of Kochia scoparia) and its active components were investigated on a compound 48/80-induced pruritogenic model in male ddY strain mice. The extract (200, 500 mg/kg, p.o.) inhibited the scratching behavior as a pruritogenic indicator. Oleanolic acid oligoglycoside, momordin Ic, isolated from the extract also exhibited the inhibition. These results suggest that Kochiae Fructus could be used as an antipruritogenic agent and its inhibitory effect may be partially attributed to momordin Ic.