Topical application of an ethanol extract prepared from Illicium verum suppresses atopic dermatitis in NC/Nga mice

Ethnopharmacological relevance

Illicium verum is a traditional herbal medicine with anti-inflammatory properties used in Asia. However, its usefulness in the treatment of allergic diseases remains unclear. This study evaluated the anti-inflammatory and antiallergic effects of I. verum extract (IVE) in a mouse model of atopic dermatitis.

Materials and methods

We investigated the effects of IVE on compound 48/80-induced histamine release, and phorbol 12-myristate13-acetate and calcium ionophore A23187-stimulated cytokines secretion in MC/9 mast cells. Atopic dermatitis was induced in NC/Nga mice by exposure to extract of house dust mite (Dermatophagoides farinae). After a topical application of IVE on ear and skin lesions, we evaluated the severity of skin symptoms, ear thickness, inflammatory cell infiltration, and serum levels of immunoglobulin E (IgE), histamine, interleukin (IL)-6, and intercellular adhesion molecule (ICAM)-1. In addition, we determined the expression of IL-4, IL-6, tumor necrosis factor (TNF)-α, interferon (IFN)-γ thymus- and activation-regulated chemokine (TARC), regulated on activation, normal T cell expressed and secreted (RANTES), ICAM-1, and vascular cell adhesion molecule (VCAM)-1 in ear tissues.

Results

IVE inhibited secretion of histamine, IL-4, IL-6, and TNF-α from mast cells in a dose-dependent manner. Topical application of IVE significantly reduced dermatitis scores, ear thickness, and serum levels of IgE, histamine, IL-6, and ICAM-1. Histopathological analysis demonstrated decreased epidermal thickening and dermal infiltration by inflammatory cells. In the ear lesions, IVE treatment reduced expression of IL-4, IL-6, TNF-α, TARC, RANTES, ICAM-1, and VCAM-1, but not IFN-γ.

Conclusions

These results indicate that IVE inhibits atopic dermatitis-like skin lesions by suppressing the expression of cytokines, chemokines, and adhesion molecules. These results suggest that IVE may be a potential therapeutic candidate for atopic dermatitis.     

Topical application of Rehmannia glutinosa extract inhibits mite allergen-induced atopic dermatitis in NC/Nga mice

Aim of the study

Rehmannia glutinosa is known in Asia as a traditional herbal medicine with anti-inflammatory properties. Atopic dermatitis (AD) is an inflammatory skin disease associated with enhanced T-helper 2 (Th2) lymphocyte responses to allergens that results in elevated serum IgE levels and leukocyte infiltration. Although some studies have shown that Rehmannia glutinosa extract (RGE) has anti-inflammatory and anti-allergic activities, these properties have not been demonstrated in AD. This study investigated the effectiveness of RGE as a therapeutic candidate in an AD model as well as its underlying mechanism of action.

Materials and methods

The effects of RGE on mite allergen (Dermatophagoides farinae)-treated NC/Nga mice were evaluated by skin symptom severity, ear thickness, production of serum IgE and histamine, and expression of cytokines, chemokines, and adhesion molecules in the ear lesions. In addition, the levels of thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), and regulated on activation, normal T cell expressed and secreted (RANTES) produced in both TNF-α- and IFN-γ-stimulated human keratinocytes were investigated by enzyme-linked immunosorbent assay (ELISA).

Results

RGE treatment of NC/Nga mice significantly reduced dermatitis scores, ear thicknesses, and serum histamine levels. Histological analyses demonstrated decreased thickening of the epidermis/dermis as well as dermal infiltration by inflammatory cells. In the ear lesions, mRNA expression levels of IL-4, TNF-α, VCAM-1, and ICAM-1 were inhibited by RGE treatment. RGE also suppressed the production of TARC, MDC, and RANTES in both the ear lesions and keratinocytes.

Conclusions

RGE inhibits the development of AD in NC/Nga mice by suppressing the expression of cytokines, chemokines, and adhesion molecules.     

Inhibitory effects of Drynaria fortunei extract on house dust mite antigen-induced atopic dermatitis in NC/Nga mice

Ethnopharmacological relevance

Drynaria fortunei (Kunze) J. Sm has been widely used in traditional medicine for the treatment of inflammation, hyperlipidemia, arteriosclerosis, rheumatism, and bone healing. We investigated the anti-inflammatory effects of a 70% ethanol extract of Drynaria fortunei (DFE).

Materials and methods

We evaluated the anti-inflammatory effects of topically applied DFE on house dust mite Dermatophargoides farinae-induced atopic dermatitis-like skin lesions in NC/Nga mice.

Results

Treatment of NC/Nga mice with DFE reduced the dermatitis score, ear thickness, and serum levels of IgE, IgG1, and IL-6. Histopathological analyses of ear and skin lesions showed inhibition of the thickening of the epidermis and reduced epidermal/dermal infiltration of inflammatory cells. In ear lesions, mRNA expression levels of IL-4, IL-6, and tumor necrosis factor-α were reduced by DFE treatment.

Conclusions

DFE inhibited the development of dermatitis-like skin lesions in NC/Nga mice. These results suggest that DFE may be a therapeutic candidate for the treatment of AD.     

Effect of Alnus japonica extract on a model of atopic dermatitis in NC/Nga mice

Aim of the study

The bark of Alnus species has long been used in traditional oriental medicine in the treatment of many pathological conditions, including fever, hemorrhage, diarrhea, alcoholism, various skin diseases (e.g. chronic herpes, eczema and prurigo), and inflammation. In order to assess the immunomodulatory efficacy of a novel herbal medicine in treating atopic dermatitis, we measured serum levels of several allergic and inflammatory biomarkers in NC/Nga mice before and after treatment with this experimental agent.

Materials and methods

Gene and protein expression analyses of iNOS and COX-2 were quantified by real time PCR and Western blot analysis and serum levels of IL-4, -5 and -13 were also measured by ELISA, all of which were reduced after treatment with the experimental agent. Additionally, serum concentrations of IgE and blood eosinophil counts were reduced in treated mice.

Results

The topical application of leaf and bark extract from Alnus japonica suppressed the development of AD-like skin lesions. The percent of blood eosinophils was decreased after treatment with leaf and bark extract from Alnus japonica. The serum IgE and Th2-related cytokine levels were decreased after treatment with leaf and bark extract from Alnus japonica compared with those treated with base cream (vehicle treated AD group). The IL-4, IL-5 and IL-13 were lower than those of vehicle treated AD group.

Conclusions

We contend that leaf and bark extract from Alnus japonica may prove useful in the treatment of atopic dermatitis and other allergic skin diseases, although more in-depth clinical studies are necessary before clinical implementation.     

Inhibitory effects of Cinnamomum cassia extract on atopic dermatitis-like skin lesions induced by mite antigen in NC/Nga mice

Aim of the study

: Cinnamomum cassia (C. cassia) has been traditionally used to treat allergic disease as well as dyspepsia, gastritis, and blood circulation disturbances. However, the antiallergic properties of C. cassia have not been fully verified using scientific tools. This study investigated the effectiveness of C. cassia extract (CCE) as an antiallergic agent in atopic dermatitis model and underlying mechanism.

Materials and methods

: The effect of CCE on mite antigen-treated NC/Nga mice was evaluated by examining skin symptom severity, levels of serum IgE, tumor necrosis factor-α (TNF-α), and histamine, skin histology, and mRNA expression of cytokines in the skin lesions. Moreover, the effect of CCE on TNF-α-and interferon-γ (IFN-γ)-induced chemokine production in human keratinocytes was investigated using ELISA.

Results

: CCE treatment of NC/Nga mice reduced the dermatitis score and the levels of serum IgE, histamine, and TNF-α. Histological examination showed inhibition of the thickening of the epidermis/dermis and reduced dermal infiltration of inflammatory cells. In skin lesions, mRNA expression of IL-4, TNF-α, and thymus and activation-regulated chemokine (TARC) was inhibited by CCE treatment. The production of TARC, macrophage-derived chemokine, and RANTES from IFN-γ-and TNF-α-stimulated human keratinocytes was suppressed by CCE treatment in a dose-dependent manner.

Conclusions

: CCE inhibits the development of atopic dermatitis-like skin lesions in NC/Nga mice by suppressing the T-helper 2 cell response.     

20-O-β-d-glucopyranosyl-20(S)-protopanaxadiol-fortified ginseng extract attenuates the development of atopic dermatitis-like symptoms in NC/Nga mice

Ethnopharmacological relevance

Ginseng and ginsenosides are frequently used in the treatment of chronic inflammatory diseases. Recently, 20-O-β-d-glucopyranosyl-20(S)-protopanaxadiol (GPD), the main metabolite of ginsenosides, was reported to have both anti-allergic and anti-pruritic effects. The immunomodulatory effects of GPD-fortified ginseng extract (GFGE) on atopic dermatitis (AD)-like symptoms in mice were investigated. This study was designed to investigate the preventive effect of GFGE on AD-like symptoms.

Materials and methods

The effects of orally administered GFGE on Dermatophagoides farinae body extract (DFE)-induced AD-like symptoms in NC/Nga mice were assessed by analyzing dermatitis score, ear thickness, scratching time, skin histological changes, and serum level of macrophage-derived chemokine (MDC). In addition, splenocytes were isolated from the mice and stimulated with anti-CD3 and anti-CD28 monoclonal antibodies to produce cytokines.

Results

Oral administration of GFGE significantly attenuated DFE-induced increases in dermatitis score, ear thickness, scratching time, and severity of skin lesions in NC/Nga mice. GFGE treatment also reduced level of MDC in serum, infiltration of eosinophils and mast cells in skin, and production of cytokines in splenocytes.

Conclusions

These results suggest that GFGE might ameliorate DFE-induced AD-like symptoms and be an alternative therapeutic agent for the prevention of AD.     

Inhibitory effects of Chelidonium majus extract on atopic dermatitis-like skin lesions in NC/Nga mice

Aim of the study

Chelidonium majus (CM) has traditionally been used for treatment of various inflammatory diseases including atopic dermatitis (AD). However its action on atopic dermatitis (AD) is unclear. Therefore, we investigated the effect of CM on AD using NC/Nga mice as an AD model.

Materials and methods

The effect of CM on 1-chloro-2,4-dinitrobenzene (DNCB) induced NC/Nga mice was evaluated by examining skin symptom severity, itching behavior, ear thickness, levels of serum immunoglobulin E (IgE), tumor necrosis factor-α (TNF-α), and interlukin-4 (IL-4), skin histology.

Results

The CM significantly reduced the total clinical severity score, itching behavior, ear thickness and the level of serum IgE in AD mouse model. CM not only decreased TNF-α but also IL-4.

Conclusion

These results suggest that CM may be a potential therapeutic modality for AD.     

Screening of the topical anti-inflammatory activity of the bark of Acacia cornigera Willdenow, Byrsonima crassifolia Kunth, Sweetia panamensis Yakovlev and the leaves of Sphagneticola trilobata Hitchcock

Ethnopharmacological relevance

An investigation of topical anti-inflammatory activity was undertaken on plants used in Central America traditional medicine.

Aim of study

Four herbal drugs used in the folk medicine of Central America to treat inflammatory skin affections (Acacia cornigera bark, Byrsonima crassifolia bark, Sphagneticola trilobata leaves and Sweetia panamensis bark) were evaluated for their topical anti-inflammatory activity.

Materials and methods

Petroleum ether, chloroform and methanol extracts were obtained for herbal medicines and then extracts were tested on Croton oil-induced ear dermatitis model in mice.

Results

Almost all the extracts reduced the Croton oil-induced ear dermatitis in mice and the chloroform ones showed the highest activity, with ID₅₀ (dose giving 50% oedema inhibition) values ranging from 112 μg/cm² (Byrsonima crassifolia) to 183 μg/cm² (Sphagneticola trilobata). As reference, ID₅₀ of the non-steroidal anti-inflammatory drug indomethacin was 93 μg/cm².

Conclusions

Lipophilic extracts from these species can be regarded as potential sources of anti-inflammatory principles.     

Effects of Korean red ginseng extract on the prevention of atopic dermatitis and its mechanism on early lesions in a murine model

Ethnopharmacological relevance

Korean red ginseng (KRG) has been shown to possess various biological activities including anti-inflammatory properties.

Aim of the study

We aimed to investigate the effects and mechanism of KRG on the prevention of atopic dermatitis (AD) using a mouse model.

Materials and methods

The effect of KRG in trinitrochlorobenzene (TNCB)-treated NC/Nga mice was assessed by measuring ear thickness, transepidermal water loss (TEWL), total serum IgE, histologic changes of lesional skin, mRNA and protein expression of thymic stromal lymphopoietin (TSLP) and tumor necrosis factor (TNF)-α, immunohistochemistry for tissue interleukin (IL)-4, IL-17, and interferon (IFN)-γ.

Results

KRG significantly reduced ear thickness. Oral administration of KRG significantly prevented the increase in TEWL induced by TNCB. The serum IgE level was significantly lower in the KRG group. Histologically, lymphocyte infiltration was markedly decreased by KRG. CD1a positive (CD1a+) cells were diminished by KRG. Immunohistochemically, KRG significantly suppressed the protein expression of TSLP and TNF-α. The mRNA expression of TSLP in the lesions was significantly reduced by KRG. These results demonstrate that oral administration of KRG may inhibit the development of AD-like skin lesions in NC/Nga mice by modifying TSLP, DCs, and at least in part, the Th2 response.

Conclusion

KRG may be a potential therapeutic modality for the prevention of AD.     

Anti-inflammatory effect of Inonotus obliquus, Polygala senega L., and Viburnum trilobum in a cell screening assay

Aim of the study

The purpose of the study was to assess the anti-inflammatory effects of the mushroom Inonotus obliquus (Chaga), Polygala senega (Senega) and Viburnum trilobum (Cranberry) bark extract fractions from locally produced materials in lipopolysaccharide (LPS) induced murine macrophage RAW 164.7 cells.

Materials and methods

Four fractions from each of the three extracts were obtained: (80% ethanol extracted; Fa), (water-soluble polysaccharide fraction; Fb), (Polyphenolic fraction; Fc) and (ETOAc/H₂O extracted fraction; Fd). These extract fractions were tested in the cell screening system at 50,100 and 500 μg/ml for their ability to inhibit LPS induced inflammatory cytokines IL-1β, TNFα and IL-6. Supernatants from LPS alone treated cells were used as control. The cytokines in the cell culture supernatants following treatments with extract fractions were quantified by ELISA method, using 96 well ELISA plates.

Results

All fractions of the extracts significantly inhibited (p < 0.05) the levels of IL-1β, IL-6 and TNFα except the polyphenolic Fc fraction of Senega which showed an increased production of IL-6. Furthermore, each fraction showed a dose-dependant anti-inflammatory effect. Nitric oxide production was not affected by cranberry and senega, while Chaga significantly reduced NO production in murine macrophage cell assay.

Conclusions

These results demonstrate that the extracts obtained from the root of Polygala senega L., bark of Viburnum trilobum, and the mushroom Inonotus obliquus possess anti-inflammatory properties when tested in a RAW 264.7 macrophage cell system.     

Effects of Bambusae caulis in Liquamen on the development of atopic dermatitis-like skin lesions in hairless mice

Ethnopharmacological relevance

Bambusae caulis in Liquamen (BCL) is a nutritious liquid extracted from heat-treated fresh bamboo stems. It is an important traditional herbal medicine used to treat coughs and asthma in East Asia. In recent years, it has been studied for its anti-inflammatory, anti-allergenic, and immune-regulating properties.

Aim of the study

To examine whether BCL suppresses the development of 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like skin lesions in hairless mice.

Materials and methods

The effects of BCL were analyzed by measuring transepidermal water loss (TEWL), melanin content, and erythema in the skin, leukocyte numbers and IgE levels in the serum, and mRNA expression of relevant cytokines in the spleen.

Results

The transdermal administration of BCL to hairless mice inhibited the development of DNCB-induced AD-like skin lesions by suppressing TEWL, melanin production and erythema of skin, the number of leukocytes and the level of IgE in serum, and the mRNA expression of IL-4, IL-13, and TNF-α in the spleen. However, BCL administration increased the expression of IFN-γ in the spleen.

Conclusions

These findings indicate that BCL suppresses the development of DNCB-induced AD-like skin lesions in hairless mice, suggesting that BCL may be a potential therapeutic agent for AD in a clinical setting.     

Oral administration of Uncariae rhynchophylla inhibits the development of DNFB-induced atopic dermatitis-like skin lesions via IFN-γ down-regulation in NC/Nga mice

Ethnopharmacological relevance

Uncariae rhynchophylla (UR) is an herb which has blood pressure lowering and anti-inflammatory effects and has been prescribed traditionally to treat stroke and vascular dementia.

Aim of study

In the present study, we examined whether UR suppress Atopic dermatitis (AD)-like skin lesions in NC/Nga mice treated with 2, 4-dinitrofluorobenzene (DNFB) under SPF conditions.

Material and methods

The effect of UR in DNFB- treated NC/Nga mice was determined by measuring the skin symptom severity, levels of serum IgE, and of the amounts of IL-4 and IFN-γ secreted by activated T cells in draining lymph nodes.

Results

Oral administration of UR to DNFB-treated NC/Nga mice was found to inhibit ear thickness increases and the skin lesions induced by DNFB. IFN-γ production by CD4+ T cells from the lymph nodes of DNFB-treated NC/Nga mice was significantly inhibited by UR treatment, although levels of IL-4 and total IgE in serum were not.

Conclusion

UR may suppress the development of AD-like dermatitis in DNFB-treated NC/Nga mice by reducing IFN-γ production.     

Quantitative evaluation of therapeutic effect of Liriope platyphylla on phthalic anhydride-induced atopic dermatitis in IL-4/Luc/CNS-1 Tg mice

Ethnopharmacological relevance

A variety of previous pharmacological studies have suggested that Liriope platyphylla may exert beneficial biological effects on inflammation, diabetes, neurodegenerative disorder, obesity, and atopic dermatitis (AD).

Aim of the study

The therapeutic effect of aqueous extract of Liriope platyphylla (AEtLP) on AD was quantified using the luciferase report system in IL-4/Luc/CNS-1 transgenic (Tg) mice.

Materials and methods

Alteration of the luciferase signal was quantified in IL-4/Luc/CNS-1 Tg mice co-treated with phthalic anhydride (PA) and AEtLP for 2 weeks using the IVIS imaging system. Phenotypes of AD were assessed by ear thickness analysis, measurement of immune-related organ weights, ELISA, and histological and pathological analysis in Tg mice.

Results

A strong luciferase signal was detected in the abdominal region of IL-4/Luc/CNS-1 Tg mice treated with only PA. However, this signal was significantly reduced in IL-4/Luc/CNS-1 Tg mice co-treated with PA+AEtLP in an AEtLP concentration-dependent manner. Especially, three organs, the thymus, pancreas, and submandibular lymph node (SL), showed a high signal response to PA treatment. Furthermore, to verify whether or not alteration of the luciferase signal is associated with AD, these disease response phenotypes were measured in the same group of mice. Common allergenic responses including increases in ear thickness, lymph node weight, IgE concentration, and infiltrated mast cells were detected in IL-4/Luc/CNS-1 Tg mice treated with PA. However, these responses were dramatically decreased by AEtLP treatment for 2 weeks.

Conclusion

These results indicate that the luciferase signal may successfully reflect the therapeutic effects of AEtLP in IL-4/Luc/CNS-1 Tg mice. Further, we suggest additional evidence that Liriope platyphylla may be considered as an effective therapeutic drug for the treatment of AD.     

Inhibition of 2,4-dinitrofluorobenzene-induced atopic dermatitis by topical application of the butanol extract of Cordyceps bassiana in NC/Nga mice

Ethnopharmacological significance

The Cordyceps species are insect-borne mushrooms that have been ethnopharmacologically used for skin diseases such as eczema and dermatitis.

Aim of the study

In this study, we investigated the curative effects of the butanol fraction (CBBF) of Cordyceps bassiana on atopic dermatitis.

Materials and methods

Dermatitis was induced by repeated application of 2,4-dinitrofluorobenzene (DNFB) in NC/Nga mice. After a topical application of CBBF on the skin lesions, the dermatitis score, epidermal thickness, mast cell number, and interleukin (IL)-4 and interferon (IFN)-γ, as well as the levels of histamine and immunoglobulin E (IgE) in the serum, were measured. Moreover, effect of CBBF on histamine release was examined using RBL-2H3 under stimulation with 2,4-dinitrophenylated bovine serum albumin (DNP-BSA).

Results

CBBF inhibited atopic dermatitis symptoms and signs in the DNFB-treated NC/Nga mice. The suppressive activity of topically applied CBBF may be due to the dose-dependent blockade of a series of immunopathological events, including the release of histamine, the production of IgE, and the secretion of IL-4 and IFN-γ. However, this extract did not directly suppress the degranulation process, assessed by measuring β-hexosaminidase release.

Conclusions

Our results suggest that CBBF can be applied as an effective herbal remedy to treat atopic dermatitis.     

Effects of Scutellariae radix and Aloe vera gel extracts on immunoglobulin E and cytokine levels in atopic dermatitis NC/Nga mice

Aim of the study

The present study aimed to investigate the effects of Scutellariae radix (SR) and Aloe vera gel (AV), alone or in combination, on levels of immunoglobulin E (IgE) and inflammatory cytokines in spontaneous atopic dermatitis(AD)-like skin lesions.

Materials and methods

After spontaneous AD-like skin lesion was developed by adaptation to conventional conditions, mice were randomly assigned to control, SR (50 mg/kg, p.o.), AV (0.8 mg/kg, p.o.) and SRAV (50 mg of SR and 0.8 mg of AV/kg, p.o.) groups, and were treated for 6 weeks.

Results

SR and SRAV suppressed IL-5 levels compared with control, but had no effects on IgE levels (P < 0.05). AV increased IgE levels, but decreased both IL-5 and IL-10 compared with control (P < 0.05).

Conclusion

These results suggest that SR and AV modulate immunological responses in AD, mainly through influencing IL-5 or IL-10 levels.     

Ultrastructural alterations of the tegument of Raillietina echinobothrida treated with the stem bark of Acacia oxyphylla (Leguminosae)

Ethnopharmacological relevance

The stem bark of Acacia oxyphylla Graham ex Bentham is used as an anthelmintic by the natives of Mizoram (North-East India).

Aim of the study

The present study was performed to evaluate whether or not the plant-derived components caused any ultrastructural changes in the tegumental interface of the parasite.

Materials and methods

The test parasite Raillietina echinobothrida, the cestode of domestic fowl, was exposed to the ethanolic crude extract and acetone fraction of stem bark of Acacia oxyphylla for varying concentrations and time duration and processed for transmission electron microscopy as soon as paralysis set in the treated parasites.

Results

Treatment with crude alcoholic extract and its acetone fraction revealed complete inactivation and flaccid paralysis of the cestode, which was soon followed by death. The treated parasites also exhibited intense vacuolization of the tegumental layers along with complete disorganization and/or erosion of microtriches.

Conclusions

Considerable structural alterations in the treated parasites are suggestive of an efficient vermicidal activity of the Acacia oxyphylla stem bark-derived botanicals against cestodes.     

Alpha-amylase inhibitory activity of two Anthocleista species and in vivo rat model anti-diabetic activities of Anthocleista djalonensis extracts and fractions

Ethnopharmacological relevance

Anthocleista djalonensis (A. Chev) and Anthocleista vogelii Planch are plants being used in West Africa traditionally to treat various diseases such as malaria, hernia, hypertension, stomach aches, hemorrhoids, syphilis, and diabetes. Diabetes causes about 5% of all deaths globally each year. Chemotherapeutic agents such as biguanides, sulfonylureas, and thiozolidinediones are available for the treatment of diabetes, however, they have undesirable side effects. The need for newer, more effective and less toxic drugs is imperative and the biodiversity of Nigeria has a high potential for drug discovery based on plants used in the ethnomedicine.

Aim of the study

To investigate the leaves, stem bark and roots of these plants for their probable alpha-amylase inhibitory activities and establish their anti-diabetic activities. The overall goal is do bioassay-guided fractionation and isolation of active anti-diabetic compounds.

Materials and methods

Powdered samples (leaves, stem bark and roots) macerated with 80% aqueous methanol were evaluated in vitro using alpha-amylase inhibitory assay while in vivo investigations were carried out on hyperglycemic rats. Diabetes was induced in albino rats by an intraperitoneal injection of alloxan monohydrate (80 mg/kg). Plant extracts (1 g/kg) were given orally for 7 days, while blood glucose levels were monitored using a one touch glucometer. The crude methanol extracts found to be most active were further partitioned into hexane and ethyl acetate fractions which were also tested in vivo on the diabetic animals.

Results

The leaves and stem bark crude methanol extracts of Anthocleista djalonensis gave comparable α-amylase inhibition of 73.66% and 72.90%, respectively which were quite higher than the 38.93% and 22.90% of the same plant parts given by Anthocleista vogelii. The crude stem bark extract of Anthocleista djalonensis exhibited significant peak blood glucose reduction on day 6 (72.59%, p<0.05) which was higher than the leaves or roots which gave 45.73% and 47.46% (p<0.05), respectively The stem bark ethyl acetate fraction of Anthocleista djalonensis gave reduction in blood glucose level of 60.86% (p<0.05).

Conclusion

From our results, the leaves, stem bark and whole root of both plants exhibited α-amylase inhibitory activities with Anthocleista djalonensis also showing good anti-diabetic activities in vivo indicating that they contain active principles for the management of diabetes. There is justification for the use of the plants traditionally to manage diabetes.     

Effects of magnolialide isolated from the leaves of Laurus nobilis L. (Lauraceae) on immunoglobulin E-mediated type I hypersensitivity in vitro

Ethnopharmacological relevance

Laurus nobilis L. (Lauraceae) has been used for folk medicines in the Mediterranean area and Europe to treat various disorders including skin inflammation (dermatitis) and asthma.

Aim of the study

Our aim was to investigate the scientific evaluation of the compounds from Laurus nobilis L. on immuniglobulin E (IgE)-mediated type I hypersensitivity responses in vitro such as atopic dermatitis and asthma.

Methods and materials

Seven compounds were isolated and examined for the mast cell stabilizing effect on IgE-sensitized RBL-2H3 mast cells by measuring the β-hexosaminidase activity. In addition, the effects on interleukin (IL)-4 production and IL-5-dependent Y16 early B cell proliferation were investigated as well as their cytotoxic effects on RBL-2H3 cells.

Results

Among the seven isolated compounds, magnolialide attenuated the release of β-hexosaminidase from RBL-2H3 cells with an IC₅₀ value of 20.2 μM, while the other compounds revealed no significant effects at concentrations tested. Furthermore, magnolialide significantly inhibited the IL-4 release with an IC₅₀ value of 18.1 μM and IL-4 mRNA expression with an IC₅₀ value of 15.7 μM in IgE-sensitized RBL-2H3 cells. In addition, the inhibition of IL-5-dependent proliferation of early B cells (Y16 cells) by magnolialide was demonstrated with an IC₅₀ value of 18.4 μM.

Conclusion

These results suggest that the magnolialide might be a candidate for the treatment of IgE-mediated hypersensitivity responses such as atopic dermatitis and asthma by inhibiting mast cell degranulation, the IL-4 production, and IL-5-dependent early B cell proliferation, key factors in the development and amplification of type I hypersensitivity reactions.     

Analgesic and anti-inflammatory effects of Cassia siamea Lam. stem bark extracts

Aim of the study

The present study was carried out to investigate analgesic and anti-inflammatory activities of Cassia siamea Lam stem bark extracts. We have also determined the cytotoxicity of each extract.

Materials and methods

C. siamea, a widespread medicinal plant traditionally used in sub-Saharan Africa, was collected in Congo Brazzaville. Stem bark was extracted with petroleum ether (CSE1), chloroform (CSE2), ethanol (CSE3) and water (CSE4). Analgesic, anti-inflammatory and antipyretic activities of these extracts were assessed in rats with hot plate test, paw pressure and carrageenan induced paw oedema. Cytotoxicity was assessed against KB and Vero cells.

Results

At the doses used (100, 200, and 400 mg/kg) ethanol and water extracts showed significant and dose-dependent analgesic and anti-inflammatory effects. None of the extracts had cytotoxic activity on KB and Vero cell lines and the most active extracts (CSE3 and CSE4) had no acute toxicity.

Conclusions

The study highlighted the analgesic and anti-inflammatory of C. siamea stem bark. Four major families of compounds present in the plant may explain these activities: triterpenes (lupeol, oleanolic acid, ursolic acid, friedelin, betulin), flavonoids (apigenin, kaempferol, luteolin), anthraquinones (emodin), phytosterols (stigmasterol, beta-sitosterol).     

Investigation for anti-inflammatory and anti-thrombotic activities of methanol extract of Capparis ovata buds and fruits

Ethnopharmacological relevance

Capparis ovata Desf. has wide natural distribution in Turkey and it is consumed in pickled form. Flower buds, root bark, and fruits of the plant are used traditionally due to their analgesic, anti-inflammatory, wound healing, anti-rheumatismal, tonic, and diuretic effects.

Aim of the study

The aim of this study was to investigate the possible anti-inflammatory and anti-thrombotic effects of methanol extracts prepared from flower buds (CBE) and fruits (CFE) of C. ovata.

Materials and methods

Anti-inflammatory effects of CBE and CFE were assessed using carrageenan-induced and prostaglandin E₂-induced mouse paw edema models. For the anti-thrombotic effect evaluation, carrageenan-induced tail thrombosis model was performed in mice. The extracts were administered intraperitonally (i.p.) at the doses of 100, 200, and 300 mg/kg. The anti-inflammatory effect of Capparis extracts were tested in comparison to 10 mg/kg diclofenac and anti-thrombotic activity to 10 and 100 IU heparin.

Results

CBE at the doses of 200, and 300 mg/kg and CFE at the doses of 100, 200, and 300 mg/kg showed significant anti-inflammatory activity and CFE reached therapeutic concentration early than CBE in carrageenan inflammation model. In prostaglandin E₂ inflammation model, CBE and CFE exhibited significant inhibitory effects. The C. ovata extracts did not show remarkable anti-thrombotic effect.

Conclusions

Based on the results obtained, it can be concluded that fruits of C. ovata have more potent anti-inflammatory effect than flower buds. It has been suggested that inhibition of cyclooxygenase pathway is one of the mechanisms of the activity. C. ovata may be potentially used as therapeutic agents for inflammatory diseases.