Flower extract of Panax notoginseng attenuates lipopolysaccharide-induced inflammatory response via blocking of NF-κB signaling pathway in murine macrophages

Aim of the study

The root of Panax notoginseng (PN) is commonly used to treat chronic liver disease with its therapeutic abilities to stop haemorrhage in the circulation, while the PN flower (PN-F) is largely unknown in the biological activities on inflammation and mechanisms of its actions. In this study, the pharmacologic effects of PN-F methanol extract on inflammation were investigated to address potential therapeutic or toxic effects in LPS-stimulated mouse macrophage cells, RAW264.7 cells.

Materials and methods

Production of NO, PGE₂ and pro-inflammatory cytokines (TNF-α and IL-1β) in supernatant, the expression of iNOS, COX-2 and cytokines, the phosphorylation of MAPK moleduces (ERK1/2, JNK and p38 MAPK), and the activation of NF-κB in PN-F extract were assayed in LPS-stimulated RAW264.7 cells.

Results

PN-F extract significantly inhibited the productions of NO, PGE₂, TNF-α and IL-1β on the LPS-stimulated RAW264.7 cells. In addition, PN-F extract suppressed the mRNA and protein expressions of iNOS, COX-2, TNF-α and IL-1β in LPS-stimulated RAW264.7 cells. The molecular mechanism of PN-F extract-mediated attenuation in RAW264.7 cells has close a relationship to suppressing the phosphorylation of MAPK molecules such as ERK1/2, JNK and p38 MAPK, and the translocation of NF-κB p65 subunit into nuclear.

Conclusion

These results indicate that PN-F extract inhibits LPS-induced inflammatory response via the blocking of NF-κB signaling pathway in macrophages, and demonstrated that PN-F extract possesses anti-inflammatory properties in vitro.     

Effects of taraxasterol on inflammatory responses in lipopolysaccharide-induced RAW 264.7 macrophages

Aim of the study

Taraxasterol, a pentacyclic-triterpene, was isolated from the Chinese medicinal herb Taraxacum officinale. In the present study, we investigated the in vitro anti-inflammatory activity of taraxasterol in lipopolysaccharide (LPS)-induced RAW 264.7 murine macrophages.

Materials and methods

RAW 264.7 cells were pretreated with 2.5, 5, or 12.5 μg/ml of taraxasterol 1 h prior to treatment with 1 μg/ml of LPS. Nitric oxide (NO) level in supernatants from cells was examined by Griess reaction, the concentrations of prostaglandin E₂ (PGE₂), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were measured by ELISA. Nuclear factor kappa B (NF-κB) activation was evaluated by immunocytochemical analysis.

Results

We found that taraxasterol inhibited NO, PGE₂, TNF-α, IL-1β and IL-6 production in LPS-induced RAW 264.7 macrophages in a dose-dependent manner. Further studies revealed that taraxasterol prevented the LPS-induced NF-κB translocation from cytoplasm into nuclear.

Conclusions

These results indicate that taraxasterol has anti-inflammatory effect by blocking NF-κB pathway.     

Chrysanthemum indicum Linné extract inhibits the inflammatory response by suppressing NF-κB and MAPKs activation in lipopolysaccharide-induced RAW 264.7 macrophages

Aims of study

Although the flowers of Chrysanthemum indicum Linné (Asteraceae) have long been used in traditional Korean and Chinese medicine to treat inflammatory diseases, the underlying mechanism(s) by which these effects are induced remains to be defined. We investigated the effects of a 70% ethanolic extract of C. indicum (CIE) on the activities of cellular signaling molecules that mediate inflammatory responses.

Materials and methods

Production of NO, PGE₂, TNF-α, and IL-1β by ELISA, mRNA and protein expression of iNOS and COX-2, phosphorylation of MAPKs, and activation of NF-κB by RT-PCR and Western blotting were examined in LPS-induced RAW 264.7 macrophages.

Results

The CIE strongly inhibited NO, PGE₂, TNF-α, and IL-1β production, and also significantly inhibited mRNA and protein expression of iNOS and COX-2 in LPS-induced RAW 264.7 macrophages, in a dose-dependent manner. Furthermore, the CIE clearly suppressed nuclear translocation of NF-κB p65 subunits, which correlated with an inhibitory effect on IκBα phosphorylation. The CIE also attenuated the activation of ERK1/2 and JNK in a dose-dependent manner.

Conclusion

Our results suggest that the anti-inflammatory properties of CIE might result from the inhibition of inflammatory mediators, such as NO, PGE₂, TNF-α, and IL-1β, via suppression of MAPKs and NF-κB-dependent pathways.     

Anti-inflammatory and antitumoural effects of Uncaria guianensis bark

Ethnopharmacological relevance

Uncaria guianensis (Aublet) Gmell (Rubiaceae) is a medicinal plant from the jungles of South and Central America, used to treat cancer, arthritis, diabetes, and inflammation. Evaluate the anti-inflammatory and anti-tumor effects of Uncaria guianensis preparations.

Materials and methods

Bio-guided fractionation of a hydroethanolic extract of Uncaria guianensis was performed, evaluating the fractions and subfractions for their effect on inflammatory mediators, tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and prostaglandin E₂ (PGE₂) by ELISA and nitric oxide (NO) by the Griess reaction in cultured supernatant from RAW 264.7 macrophages stimulated with lipopolysaccharide (LPS). The expression of cyclooxygenase 2 (COX-2), inducible nitric oxide synthase (iNOS) and inhibitor of κB (IκB) were investigated in RAW 264.7 macrophages by flow cytometry. The activity of NF-κB in HeLa cells transfected with a luciferase reporter system was determined. The effect of Uncaria guianensis on the inflammatory response in vivo was assessed in BALB/c mice stimulated with LPS, on rat paw oedema induced by carrageenan, and on tumour growth and lung metastasis in BALB/c mice inoculated with 4T1 mammary tumour cells. Immune cell infiltrates and inflammatory mediators were evaluated in the tumour by immunohistochemistry.

Results

Sub-fraction Ug AIV inhibited, to varying degrees, NO, TNF-α, IL-6 and PGE₂ production by macrophages in vitro (30 μg/ml) and in the serum of LPS-challenged mice (5 mg/kg). Macrophage expression of Cox-2 was inhibited (35%), IκB degradation was completely inhibited and NF-κB activation was inhibited (70%) by Ug AIV at 30 μg/ml. Ug AIV decreased paw oedema by 86% (5 mg/kg) and serum NO and TNF-α by 45% and 65% respectively. Ug AIV reduced 4T1 mammary tumour growth by 91% on day 33 post-inoculation as well as the levels of serum NO, IL-6 and TNF-α in the same animals. Ug AIV decreased the number of tumour-infiltrating T lymphocytes, macrophages and neutrophils as well as the number of cells positive for COX-2, iNOS, IL-6, TNF-α and p65.

Conclusions

As Ug AIV was not cytotoxic for tumour cells or macrophages, its anti-tumour effect may be due to a reduction in pro-tumoural inflammatory processes in the tumour microenvironment, possibly mediated through NF-κB.     

Anti-inflammatory and anti-arthritic activity of total flavonoids of the roots of Sophora flavescens

Ethnopharmacological relevance

The roots of Sophora flavescens have long been used in Chinese medicine for the treatment of fever, inflammatory disorders, ulcers and skin burns. Sophora flavescens contains flavonoids and alkaloids.

Aim of the study

This study was conducted to develop a plant-based anti-inflammatory agent focused on chronic inflammatory disorders. To accomplish this, the alkaloid-free prenylated flavonoid-enriched fraction (PFS) of rhizomes of Sophora flavescens was prepared and its in vitro and in vivo anti-inflammatory activities were then evaluated for the first time.

Materials and methods

The inhibitory activity of PFS on PGE₂, NO, IL-6 and TNF-α production of lipopolysaccharide (LPS)-treated RAW 264.7 cells was measured. Additionally, adjuvant-induced arthritis in rats was used as an animal model of chronic inflammation to establish the in vivo anti-inflammatory effects of PFS.

Result

PFS inhibited cyclooxygenase-2 (COX-2)-catalyzed PGE₂ and inducible nitric oxide synthase (iNOS)-catalyzed NO production by lipopolysaccharide (LPS)-treated RAW 264.7 cells at 10–50 μg/ml, and these effects primarily occurred via COX-2 inhibition and iNOS down-regulation, respectively. PFS also inhibited IL-6 and TNF-α production. When tested against adjuvant-induced arthritis in rats (chronic inflammation), PFS strongly inhibited arthritic inflammation when administered orally at doses of 10–100 mg/kg/day. In addition, PFS administered orally potently inhibited acetic acid-induced writhing in mice.

Conclusions

Our results suggest that PFS inhibits chronic inflammatory response and the inhibition of proinflammatory molecules such as COX-2, iNOS and IL-6 may contribute, at least in part, to the anti-inflammatory activity in vivo. Overall, these results indicate that PFS from Sophora flavescens may have the potential for treatment of chronic inflammatory disorders such as rheumatoid arthritis.     

Atropa acuminata Royle Ex Lindl. blunts production of pro-inflammatory mediators eicosanoids., leukotrienes,cytokines in vitro and in vivo models of acute inflammatory responses

Ethnopharmacological relevance

Atropa acuminata Royle Ex Lindl. has been widely used in folk medicine for several inflammatory disorders such as arthritis, asthma, conjunctivitis, encephalitis, pancreatitis, peritonitis, acute infections and neuroinflammatory disorders.

Aim of the study

Our aim was to evaluate Atropa acuminata for its anti-inflammatory properties and to delineate its possible mechanism of action on the modulation of the inflammatory mediators.

Materials and methods

We investigated the inhibitory action of ethanolic extract of Atropa acuminata (AAEE) on production of NO, TNF-α and IL-1β in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and also assayed it for COX 1/2 and 5-LOX inhibitory activities. Next AAEE was tested in acute inflammatory animal models., carragenean induced rat paw edema, carragenean induce pleurisy in rats and vascular permeability in mice and the effects on NO, PGE₂ and LTB₄ production in the pleural fluid and paw exudates were evaluated. In addition the effects on leukocyte migration and exudation and vascular permeability were also observed.

Results

Our findings summarized novel anti-inflammatory mechanisms for Atropa acuminata based on dual in vitro cyclooxygenase 1/2/ and 5-Lipoxygenase inhibitory activities and also significant downregulation of nitric oxide (NO) and pro-inflammatory cytokin (TNF-α and Il-1 β) release in LPS-stimulated RAW 246.7 macrophage cell line. In acute inflammatory models in vivo (carragenean induced edema, carragenean induced pleurisy in rats and vascular permeability in mice), AAEE exhibited an extensive diverse mechanism for anti-inflammatory properties. This was indicated on the basis of dose dependent suppression of multi targeted inflammatory mediators., NO, TNF-α and IL-1β, eicosanoids., PGE₂ and leukotrienes., LTB₄ along with significantly decreased leucocyte migration, exudation and decreased vascular permeability. These effects were more potent and prolonged than traditional NSAIDS, thereby indicating fewer side effects. AAEE was found to be safe for long term administration, as confirmed by the results of acute toxicity studies and MTT assay. The complex mode of action of the herbs was attributed possibly due to the high polyphenolic, flavanol and flavonoid content present in the extracts as observed by means of quantitative screening for phytochemicals.

Conclusion

Our study provides scientific evidence to support the traditional anti-inflammatory uses of Atropa acuminata and is probably due to inhibitory effects on multiple inflammatory mediators which indicates a promising potential for the development of a strong anti-inflammatory agent from this plant.     

Mechanism of anti-inflammatory activity of umbelliferone 6-carboxylic acid isolated from Angelica decursiva

Aims of the study

We recently reported the potential antioxidant and anti-inflammatory activities of umbelliferone 6-carboxylic acid (UMC) isolated from the whole plants of Angelica decursiva. In this study, we elucidated the anti-inflammatory mechanisms of UMC in vitro and in vivo.

Methods

The inhibitory effects of UMC on the production of nitric oxide (NO), prostaglandin E₂ (PGE₂), and tumor necrosis factor-α (TNF-α), the expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the activation of nuclear factor kappa B (NF-κB) were evaluated using lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The reactive oxygen species (ROS) generation inhibitory activity of UMC was evaluated using t-butyl hydroperoxide (t-BHP)-induced RAW 264.7 cells. Furthermore, the in vivo anti-inflammatory activity of UMC was evaluated using carrageenan induced mouse paw edema model.

Results

UMC dose-dependently inhibited NO and PGE₂ production by down-regulating iNOS and COX-2 protein expression in LPS-stimulated RAW 264.7 macrophages. UMC also suppressed the production of the proinflammatory cytokine TNF-α in LPS stimulated RAW 264.7 cells in a concentration dependent manner. In addition, UMC dose-dependently prevented LPS-induced nuclear translocation of NF-κB in RAW 264.7 macrophages. Furthermore, UMC exhibited the inhibitory activity against t-BHP-induced ROS generation in RAW 264.7 cells with an IC₅₀ value of 705.1 μg/ml. Moreover, UMC inhibited λ-carrageenan induced mouse paw edema by 70.40 and 60.20% at doses of 50 and 25 mg/kg body weight, respectively.

Conclusion

The combined results of this study indicate that UMC is an important anti-inflammatory constituent of A. decursiva and its anti-inflammatory effect was due to its ability to inhibit the production of inflammatory mediators via inhibition of NF-κB activation pathway.     

Aloe-emodin from rhubarb (Rheum rhabarbarum) inhibits lipopolysaccharide-induced inflammatory responses in RAW264.7 macrophages

Ethnopharmacological relevance

Rheum rhabarbarum (rhubarb) has long been used for the treatment of inflammation in China and other Asian countries. However, the mechanism underlying the anti-inflammatory activity of this medicinal plant is not fully understood. The present study was designed to investigate the anti-inflammatory effects of anthraquinones, the major constituents in rhubarb, and the molecular mechanism involved in their anti-inflammatory effects.

Materials and methods

RAW264.7 cells were stimulated by lipopolysaccharide (LPS) in the presence or absence of the compounds examined. The proliferation of RAW264.7 cells was assayed by the Alamar-Blue method. The quantity of nitric oxide (NO) was determined by Griess assay. The expression of pro-inflammatory cytokines was determined by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time PCR. Inducible nitric oxide synthase (iNOS), inhibitor of nuclear factor κBα (IκBα), extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), c-Jun NH2-terminal kinase (JNK), and Akt/phosphoinositide 3-kinase (PI3K) protein expression levels were determined by Western blotting.

Results

Aloe-emodin markedly suppressed the production of NO, interleukin-6 (IL-6), and interleukin-1β (IL-1β) in LPS-stimulated RAW264.7 cells with no apparent cytotoxicity. The mRNA expression levels of iNOS, IL-6, and IL-1β genes were also significantly inhibited by aloe-emodin. Western blot analysis showed that aloe-emodin suppressed LPS-induced iNOS protein expression, IκBα degradation, and the phosphorylation of ERK, p38, JNK, and Akt.

Conclusions

These results demonstrate that aloe-emodin is the bioactive component of rhubarb that confers an anti-inflammatory effect through a likely mechanism involving a decrease in pro-inflammatory cytokine production in LPS-induced RAW264.7 macrophages via inhibition of NF-κB, MAPK, and PI3K pathways.     

Anti-inflammatory effects of YeongyoSeungma-tang

Ethnopharmacological relevance

YeongyoSeungma-tang which includes Fructus Forsythia, has been used in oriental traditional medicine for treatment of early smallpox and atopic dermatitis.

Aim of the study

YeongyoSeungma-tang was carried out to investigate for anti-inflammatory effects.

Materials and methods

YeongyoSeungma-tang was tested for anti-inflammatory effects against lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E₂ (PGE₂), and tumor necrosis factor alpha (TNF-α) releases as well as nuclear factor kappa B (NF-κB) expression using RAW264.7 macrophage cells.

Results

YeongyoSeungma-tang significantly inhibited generation of NO (42% and 59% inhibition at doses of 5 μg/mL and 10 μg/mL, respectively), PGE₂ (46% and 80% inhibition at doses of 5 μg/mL and 10 μg/mL, respectively) and TNF-α (6% and 23% inhibition at doses of 5 μg/mL and 10 μg/mL, respectively) on LPS-stimulated RAW 264.7 cells in a concentration-dependent manner. Consistently in these observations, the expression of inducible NO synthase (iNOS) enzyme was also inhibited by YeongyoSeungma-tang. However, YeongyoSeungma-tang did not show any influence on the expression of cyclooxygenase-2. The cream containing 0.075% YeongyoSeungma-tang showed good skin moisturizing effect without any irritation.

Conclusion

The present study may support the fact that YeongyoSeungma-tang can have the good possibility as an anti-inflammatory agent for troubled skins.     

Suppressive effects of wild bitter gourd (Momordica charantia Linn. var. abbreviata ser.) fruit extracts on inflammatory responses in RAW 264.7 macrophages

Aim of the study

Bitter gourd (Momordica charantia) is used to treat various diseases including inflammation. A wild species of bitter gourd, Momordica charantia Linn. var. abbreviata ser. (WBG), is considered to be more potent in disease prevention than is bitter gourd; however, little is known about the biological and physiological characteristics of WBG.

Materials and methods

The present study investigated the anti-inflammatory effect of WBG on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages.

Results

Among the hot water, 95% ethanol, and ethyl acetate extracts of WBG, the ethanol extract showed the greatest reduction of LPS-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂) production and inducible nitric oxide synthase (iNOS) and pro-interleukin-1β expression. LPS-induced cyclooxygenase-2 expression was not affected by WBG extracts. Compared with WBG, extracts from bitter gourd showed a lesser inhibition of LPS-induced events. Electrophoretic mobility shift assay further showed that both the hot water and the ethanol extracts of WBG inhibited NF-κB activation. Although information is lacking on the bioactive components of WBG, the phenolic compound contents of each extract significantly paralleled its anti-inflammatory ability (r = 0.74, 0.88 and 0.65 for NO, PGE₂ and iNOS expression, respectively, P < 0.05).

Conclusions

These results suggest that WBG is beneficial for reducing LPS-induced inflammatory responses by modulating NF-κB activation.     

In vivo and in vitro anti-inflammatory activity of Lentinus polychrous extract

Ethnopharmacological relevance

Lentinus polychrous is a Thai local edible mushroom, traditionally used for the treatments of fever and inflammation due to snake or scorpion envenomation.

Aim of study

The present study aimed to investigate an anti-inflammatory effect of Lentinus polychrous mycelial extract (LPME) both in vitro and in vivo.

Materials and methods

The cytotoxicity and suppressive effects of LPME on nitric oxide production, intracellular O₂⁻ production, pro-inflammatory mediator expression, TNF-α production were determined by using LPS-activated RAW 264.7 cells. In addition, Anti-inflammatory effect of LPME was evaluated by using carageenan-induced paw edema in rats.

Results

The LPME exhibited cytotoxicity with 50% inhibitory concentration (IC₅₀) of 280.25±10.10 μg/ml and significantly suppressed the productions of NO and intracellular O₂⁻ with dose-dependent manner. LPME decreased the expressions of iNOS, IL-1β, IL-6, TNF-α and COX-2 and significantly decreased the TNF-α production in LPS-activated macrophage with dose-dependent manners. Moreover, LPME showed significant suppressive effect on paw edema in rats.

Conclusion

The results clearly revealed that the LPME inhibited NO and pro-inflammatory productions by down-regulating the gene expressions of pro-inflammatory mediators leading to the decrease paw edema in rat which support the traditional use.     

Effects of taraxasterol on iNOS and COX-2 expression in LPS-induced RAW 264.7 macrophages

Ethnopharmacological relevance

Taraxasterol was isolated from the Chinese medicinal herb Taraxacum officinale which has been frequently used as a remedy for inflammatory diseases. Our previous study has shown that taraxasterol inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in RAW 264.7 macrophages. To elucidate the underlying mechanism responsible for these effects, in the present study, we investigated the effects of taraxasterol on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, and mitogen-activated protein kinases (MAPKs) signaling pathway in LPS-induced RAW 264.7 macrophages.

Materials and methods

RAW 264.7 cells were pretreated with 2.5, 5 and 12.5 μg/ml of taraxasterol 1 h prior to treatment with 1 μg/ml of LPS. The mRNA expression levels of iNOS and COX-2 were examined by RT-PCR. The protein expression levels of iNOS and COX-2, and the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), p38 and c-Jun N-terminal kinase (JNK) MAPKs were measured by Western blot.

Results

The mRNA and protein expression levels of iNOS and COX-2 were inhibited by taraxasterol in a concentration-dependent manner. Further studies revealed that taraxasterol suppressed the phosphorylation of ERK1/2 and p38 in LPS-induced RAW 264.7 macrophages.

Conclusions

These results indicate that taraxasterol inhibits iNOS and COX-2 expression by blocking ERK1/2 and p38 MAPKs signaling pathway.     

Anti-inflammatory effects of methanol extracts of the root of Lilium lancifolium on LPS-stimulated Raw264.7 cells

Aim of the study

Lilium lancifolium is commonly used to treat bronchitis, pneumonia, etc. In this study, we investigated the anti-inflammatory effects of methanol extracts of the root of Lilium lancifolium (LL extracts) in LPS-stimulated Raw264.7 cells.

Material and methods

Levels of NO, PGE₂ and pro-inflammatory cytokines (IL-6 and TNF-α) in the supernatant fraction were determined using sandwich ELISA. Expression of COX-2 and iNOS, phosphorylation of MAPK subgroups (ERK and JNK), and NF-κB activation in extracts were detected via Western blot and immunocytochemistry assays.

Results

The LL extract significantly inhibited NO, PGE₂, IL-6 and TNF-α production in LPS-stimulated cells, and suppressed iNOS and COX-2 expression. A mechanism-based study showed that phosphorylation of ERK1/2 and JNK and translocation of the NF-κB p65 subunit into nuclei were inhibited by the LL extract. Furthermore, interleukin-4 and interleukin-13 production in Con A-induced splenocytes was suppressed.

Conclusion

These results indicate that anti-inflammatory effects of methanol extracts from Lilium lancifolium are due to downregulation of iNOS and COX-2 via suppression of NF-κB activation and nuclear translocation as well as blocking of ERK and JNK signaling in LPS-stimulated Raw264.7 cells.     

Canna indica L. attenuates high-glucose- and lipopolysaccharide-induced inflammatory mediators in monocyte/macrophage

Ethnopharmacological relevance

Canna indica L. (CI) has been widely used as a folklore medicine in tropical and subtropical areas with beneficial effects in numerous diseases, including infection, rheumatism, hepatitis, and it has also been identified as an antioxidant.

Materials and methods

The present study aimed to investigate the effect of Canna indica CI ethanolic extract (CIE) on productions of nitric oxide (NO), prostaglandin E₂ (PGE₂), and interleukin-1β (IL-1β) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. In addition, the effects of CIE in high glucose (HG)-induced U937 monocytes on mRNA expressions of IL-8 and monocyte chemoattractant protein-1 (MCP-1), and regulation of mitogen-activated protein kinase (MAPK) pathways were also identified.

Results

CIE was found to inhibit the production of inflammatory mediators including NO, IL-1β, and PGE₂ from LPS-induced RAW 264.7 macrophages. The increases in HG-induced mRNA expressions of IL-8 and MCP-1 were also significantly inhibited by CIE. Stimulation of HG in U937 monocytes resulted in activation of p38 MAPK, ERK1/2, and JNK. However, CIE treatment significantly decreased phosphorylation of p38 MAPK, ERK1/2, and JNK.

Conclusion

The present study demonstrated that CIE suppressed the LPS-induced inflammatory mediator production and also inhibited HG-induced inflammatory mediator expression by the regulation of MAPK pathway.     

Biomolecular evidence of anti-inflammatory effects by Clematis mandshurica Ruprecht root extract in rodent cells

Ethnopharmacological relevance

Clematis mandshurica Ruprecht root is widely used in Asia as an analgesic and anti-inflammatory agent. This research investigated the anti-inflammatory effects of Clematis mandshurica Ruprecht root extract (CRE) using RAW 264.7 macrophage cells and carrageenan- (CA-) induced rat paw edema.

Materials and methods

Production of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, nitric oxide (NO) and prostaglandin E₂ (PGE₂) in the culture supernatant, mRNA expression of TNF-α, IL-1β, IL-6, iNOS and COX-2, protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) in the extract were assayed. In addition, the effect of CRE on acute inflammation in vivo was observed using CA-induced rat hind paw edema assay. The changes on the histopathology and histomorphometry of hind paw skins—dorsum and ventrum pedis were observed using CA-treated rats.

Results

Treatment with CRE (0.25, 0.5, and 1 mg/mL) resulted in inhibited levels of protein expression of lipopolysaccharide- (LPS-) induced iNOS, COX-2, NF-κB, and MAPKs (ERK, JNK, and p38) as well as production of TNF-α, IL-1β, IL-6, NO, and PGE₂ induced by LPS. Consistent with these results, CRE reduced the LPS-induced expressions of these cytokines, iNOS and COX-2 at the mRNA levels in a dose-dependent manner. In particular, results of the CA-induced rat hind paw edema assay showed an anti-edema effect of CRE. In addition, treatment with CRE resulted in dose-dependent inhibition of CA-induced increases of skin thickness, mast cell degranulation, and infiltrated inflammatory, TNF-α, IL-1β, iNOS, and COX-2-positive cells in both dorsum and ventrum pedis skin, respectively.

Conclusions

These results demonstrate that CRE exhibits anti-inflammatory activities via decreasing production of pro-inflammatory mediators through suppression of the pathways of NF-κB and MAPKs in LPS-induced macrophage cells. In addition, results of the CA-induced rat hind paw edema assay show an anti-edema effect of CRE. Our findings also support the traditional use of CRE in the inflammatory symptoms of rheumatic arthritis and acute icteric hepatitis. Thus, CRE may have therapeutic potential for a variety of inflammation-mediated diseases and may be developed into potent anti-inflammatory drugs.     

Effect of Rhizoma Polygonati on 12-O-tetradecanoylphorbol-acetate-induced ear edema in mice

Ethnopharmacological relevance

Rhizoma Polygonati is originated from the dried rhizomes of Polygonatum sibircum Red. It has long been used in traditional Chinese medicine for the treatment of inflammatory disorders.

Aim of the study

The present study aims to investigate the anti-inflammatory effect of aqueous extract of Rhizoma Polygonati (ERP) in a mouse model of inflammation induced by 12-O-tetradecanoylphorbol-acetate (TPA).

Materials and methods

The anti-inflammatory effect was evaluated by measuring the ear thickness and activity of myeloperoxidase (MPO). The anti-inflammatory mechanism was explored by determining the protein and mRNA levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6.

Results

The results showed that ERP significantly decreased the ear thickness and MPO activity in mouse model of inflammation induced by TPA. In addition, ERP also remarkably inhibited the protein and mRNA levels of iNOS, COX-2, TNF-α, IL-1β, and IL-6.

Conclusions

These results indicate that ERP has potential anti-inflammatory effect on TPA-induced inflammatory in mice, and the anti-inflammatory effect may be mediated, at least in part, by inhibiting the mRNA expression of a panel of inflammatory mediators including iNOS, COX-2, TNF-α, IL-1β, and IL-6.     

Molecular mechanism of anti-inflammatory activity of Pluchea indica leaves in macrophages RAW 264.7 and its action in animal models ofinflammation

Ethnopharmacological relevance: Pluchea indica Less.

(Asteraceae) is a Thai medicinal plant used in traditional medicine for the treatment of hemorrhoids, lumbago, leucorrhoea and inflammation. This study investigated the molecular mechanism of anti-inflammatory activity of Pluchea indica leaf extract in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and also determined its action in acute inflammation animal models.

Materials and methods

The inhibitory effect of Pluchea indica leaf extract on LPS-induced nitric oxide (NO) production was evaluated by Griess reaction. Protein and mRNA expressions were determined by real time RT-PCR and Western blotting analysis, respectively. Inducible nitric oxide synthase (iNOS) promoter activity was evaluated by iNOS promoter based reporter gene assay. In vivo anti-inflammatory effect was examined in ethylphenylpropiolate (EPP)-induced ear edema and carrageenan-induced paw edema in rat models.

Results

Ethyl acetate fraction of ethanol extract of Pluchea indica leaves (EFPI) exhibited the potent inhibitory effect on NO production in LPS-induced macrophages and also inhibited PGE₂ release. EFPI reduced iNOS mRNA and protein expression through suppressed iNOS promoter activity and nuclear translocation of subunit p65 of nuclear factor-κB, but did not inhibit phosphorylation of the mitogen-activated protein kinases (MAPKs). Moreover, EFPI possessed anti-inflammatory activities on acute phase of inflammation as seen in EPP-induced ear edema and carrageenan-induced paw edema inrats.

Conclusions

These data support the pharmacological basis of Pluchea indica plant as a traditional herbal medicine for treatment of inflammation.