Bisgma stimulates prostaglandin E2 production in macrophages via cyclooxygenase-2, cytosolic phospholipase A2, and mitogen-activated protein kinases family

Novel oxicam nonsteroidal compound XK01 attenuates inflammation by suppressing the NF-κB and MAPK pathway in RAW264.7 macrophages

Traditional non-steroidal anti-inflammatory drugs (NSAIDs) show serious adverse effects during clinical use, which limits their usage. Oxicams (e.g., piroxicam, meloxicam) are widely used as NSAIDs. However, selectivity to cyclooxygenase (COX) 2 may cause cardiovascular problems considering the long-term use of the drugs. Therefore, it is important to develop new non-steroidal compounds as anti-inflammatory drugs. In the present study, we evaluated the anti-inflammatory activity of a newly developed nonsteroidal drug XK01. Our data showed that XK01 reduced the contents of nitric oxide (NO) and reactive oxygen species (ROS)and inhibited the transcription levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated mouse RAW264.7 macrophages. XK01 showed no significant inhibitory effect on COX-1, but inhibited the expression of COX-2. At molecular level, XK01 prevented the translocation of p65 protein from the cytoplasm to the nucleus and inhibited the phosphorylation of p65, IκB, and MAPKs proteins. And high concentration of XK01 also inhibited the phosphorylation of JNK, p38 and ERK, showing stronger effect than that of meloxicam. In addition, the anti-inflammatory activity of XK01 was further validated in Xylene-induced mouse ear swelling model. Thus, this study verified that XK01 inhibits the expression of inflammatory mediators and COX-2, and exhibits potential anti-inflammatory effects via suppressing the NF-κB and MAPK pathway.

Assessment of Cytotoxic and Genotoxic Effect of Modern Dental Materials in vivo

Objectives

The aim of the study was to assess the biocompatibility of modern composite and amalgam dental fillings.

Material and Methods

The research was conducted on 150 healthy patients between the ages of 10 and 20 who had amalgam and composite fillings between 6 and 12 months. Under in vivo conditions, a swab of buccal cells near the fillings was taken, and the cytotoxic and genotoxic impact of composite and amalgam fillings on these cells was analyzed using the extended micronucleus test (cytomeassay).

Results

The results showed statistically significant differences between the groups of subjects with amalgam and composite fillings and subjects without fillings for the following parameters: number of micronuclei (p=0.006), number of buds (p<0.001), number of binuclear cells (p<0.001), number of nucleoplasmic bridges (p<0.001).The number of micronuclei was statistically significantly higher in the group of subjects with amalgam and composite fillings compared to the group without fillings. The results for nuclear buds, for the number of binuclear cells and the number of nucleoplasmic bridges showed that the group with amalgam fillings had a statistically significantly higher number of these changes compared to other groups.The results of the analysis of the relationship between the parameters of the micronucleus test and the number of amalgam and composite surfaces did not show statistically significant values. Parameters indicating cell cytotoxicity were not statistically significantly elevated in subjects with fillings. The results of the analysis of the influence of the patients' lifestyle on the results of the micronucleus test showed statistically significant results for certain predictors (diagnostic X-ray radiation, coffee consumption, consumption of cooked, dried meat and baked food).

Conclusion

Based on the results, it can be concluded that the buccal cells of subjects with amalgam fillings showed the highest degree of genotoxic changes, followed by those with composite fillings and the least buccal cells of patients without fillings.

In Vitro Evaluation of Candida albicans Adhesion on Heat-Cured Resin-Based Dental Composites

Microbial adhesion on dental restorative materials may jeopardize the restorative treatment long-term outcome. The goal of this in vitro study was to assess Candida albicans capability to adhere and form a biofilm on the surface of heat-cured dental composites having different formulations but subjected to identical surface treatments and polymerization protocols. Three commercially available composites were evaluated: GrandioSO (GR), Venus Diamond (VD) and Enamel Plus HRi Biofunction (BF). Cylindrical specimens were prepared for quantitative determination of C. albicans S5 planktonic CFU count, sessile cells CFU count and biomass optical density (OD570 nm). Qualitative Concanavalin-A assays (for extracellular polymeric substances of a biofilm matrix) and Scanning Electron Microscope (SEM) analyses (for the morphology of sessile colonies) were also performed. Focusing on planktonic CFU count, a slight but not significant reduction was observed with VD as compared to GR. Regarding sessile cells CFU count and biomass OD570 nm, a significant increase was observed for VD compared to GR and BF. Concanavalin-A assays and SEM analyses confirmed the quantitative results. Different formulations of commercially available resin composites may differently interact with C. albicans. The present results showed a relatively more pronounced antiadhesive effect for BF and GR, with a reduction in sessile cells CFU count and biomass quantification.

Rutin alleviates bisphenol A-glycidyl methacrylate-induced generation of proinflammatory mediators through the MAPK and NF-κB pathways in macrophages

Bisphenol A-glycidyl methacrylate (BisGMA) is a methacrylate monomer that is mainly used in three-dimensional structures to reconstruct dental and bony defects. BisGMA has toxic and proinflammatory effects on macrophages. Rutin is a natural flavonol glycoside that is present in various plants and has useful biological effects, such as anti-inflammatory, anticancer, and antioxidative effects. The aim of this study was to investigate the anti-inflammation of rutin in macrophages after exposure to BisGMA. Pretreatment of the RAW264.7 macrophage with rutin at 0, 10, 30, and 100 μM for 30 min before being incubated with BisGMA at 0 or 3 μM. Proinflammatory cytokines and prostaglandin (PG) E2 were detected by enzyme-linked immunosorbent assay (ELISA). Nitric oxide (NO) was detected by the Griess assay. Expression and phosphorylation of proteins were measured by Western blot assay. Pretreatment with rutin inhibited the BisGMA-induced generation of proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and PGE2, in macrophages. Rutin also suppressed the BisGMA-induced secretion of NO and expression of inducible nitric oxide synthase (iNOS) in a concentration-dependent manner. Furthermore, rutin suppressed the mitogen-activated protein kinase (MAPK) phosphorylation in a concentration-dependent manner. Finally, rutin suppressed the BisGMA-induced phosphorylation of nuclear factor (NF)-κB p65 and degradation of inhibitor of κB (IκB). These results indicate that the concentration of rutin has an inhibitory effect on proinflammatory mediator generation, MAPK phosphorylation, NF-κB p65 phosphorylation, and IκB degradation. In conclusion, rutin is a potential anti-inflammatory agent for BisGMA-stimulated macrophages through NF-κB p65 phosphorylation and IκB degradation resulting from MAPK phosphorylation.

Protective effect of wogonin on inflammatory responses in BisGMA-treated macrophages through the inhibition of MAPK and NFκB pathways

Composites, resins, and sealants that are commonly used in orthopedics and dentistry are based on 2,2-bis[p-(2'-hydroxy-3'-methacryloxypropoxy)phenylene]propane (BisGMA), which induces proinflammatory responses in macrophages. The present study aimed to explore the anti-inflammatory responses of wogonin, which is a natural dihydroxyl flavonoid compound, in BisGMA-treated macrophages. According to the findings, wogonin exhibits anti-inflammatory, antiallergic, anticancer, and antioxidative properties. The generation of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS) were noted to be inhibited by wogonin in BisGMA-treated macrophages. Furthermore, the production of proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 was reduced. In addition, BisGMA-induced nuclear factor (NF)-κB p65 phosphorylation and inhibitor of κB (IκB) degradation were inhibited. Finally, the BisGMA-induced phosphorylation of mitogen-activated protein kinases (MAPKs), including p38 MAPK, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) was inhibited. All these effects were induced by wogonin in the macrophages in a concentration-dependent manner. Similar inhibitory effects of wogonin were observed on the production of NO and proinflammatory cytokines, expression of iNOS, phosphorylation of NF-κB p65 and MAPK, and degradation of IκB. These results indicated that rutin is a potential anti-inflammatory agent for BisGMA-treated macrophages that undergo NFκB p65 phosphorylation and IκB degradation through upstream MAPK phosphorylation. Therefore, wogonin inhibits BisGMA-induced proinflammatory responses in macrophages through the regulation of the NFκB pathway and its upstream factor, MAPK.

Biodegradation of Dental Resin-Based Composite—A Potential Factor Affecting the Bonding Effect: A Narrative Review

In recent years, although resin composite has played an important role in the restoration of tooth defects, it still has several disadvantages, including being biodegraded by saliva, bacteria and other enzymes in the oral cavity, which may result in repair failure. This factor is not conducive to the long-term survival of the prosthesis in the mouth. In this article, we review the causes, influencing factors and prevention methods of resin biodegradation. Biodegradation is mainly caused by esterase in saliva and bacteria, which breaks the ester bond in resin and causes the release of monomers. The mechanical properties of the prosthesis can then be affected. Meanwhile, cathepsin and MMPs are activated on the bonding surface, which may decompose the dentin collagen. In addition, neutrophils and residual water on the bonding surface can also aggravate biodegradation. Currently, the primary methods to prevent biodegradation involve adding antibacterial agents to resin, inhibiting the activity of MMPs and enhancing the crosslinking of collagen fibers. All of the above indicates that in the preparation and adhesion of resin materials, attention should be paid to the influence of biodegradation to improve the prosthesis’s service life in the complex environment of the oral cavity.

Antibacterial and Antibiofilm Properties of Three Resin-Based Dental Composites against Streptococcus mutans

Antibacterial and antibiofilm properties of restorative dental materials may improve restorative treatment outcomes. The aim of this in vitro study was to evaluate Streptococcus mutans capability to adhere and form biofilm on the surface of three commercially available composite resins (CRs) with different chemical compositions: GrandioSO (VOCO), Venus Diamond (VD), and Clearfil Majesty (ES-2). Disk-shaped specimens were manufactured by light-curing the CRs through two glass slides to maintain a perfectly standardized surface topography. Specimens were subjected to Planktonic OD_600nm, Planktonic CFU count, Planktonic MTT, Planktonic live/dead, Adherent Bacteria CFU count, Biomass Quantification OD_570nm, Adherent Bacteria MTT, Concanavalin A, and Scanning Electron Microscope analysis. In presence of VOCO, VD, and ES2, both Planktonic CFU count and Planktonic OD_600nm were significantly reduced compared to that of control. The amount of Adherent CFUs, biofilm Biomass, metabolic activity, and extracellular polymeric substances were significantly reduced in VOCO, compared to those of ES2 and VD. Results demonstrated that in presence of the same surface properties, chemical composition might significantly influence the in vitro bacterial adhesion/proliferation on resin composites. Additional studies seem necessary to confirm the present results.

Meta-analytical analysis on components released from resin-based dental materials

OBJECTIVES

Resin-based materials are applied in every branch of dentistry. Due to their tendency to release substances in the oral environment, doubts have been raised about their actual safety. This review aims to provide a comprehensive analysis of the last decade literature regarding the concentrations of elutable substances released from dental resin-based materials in different type of solvents.

MATERIALS AND METHODS

All the literature published on dental journals between January 2010 and April 2022 was searched using international databases (PubMed, Scopus, Web of Science). Due to strict inclusion criteria, only 23 papers out of 877 were considered eligible. The concentration of eluted substances related to surface and volume of the sample was analyzed, considering data at 24 h as a reference. The total cumulative release was examined as well.

RESULTS

The most eluted substances were HEMA, TEGDMA, and BPA, while the less eluted were Bis-GMA and UDMA. Organic solvents caused significantly higher release of substances than water-based ones. A statistically significant inverse correlation between the release of molecules and their molecular mass was observed. A statistically significant positive correlation between the amount of released molecule and the specimen surface area was detected, as well as a weak positive correlation between the release and the specimen volume.

CONCLUSIONS

Type of solvent, molecular mass of eluates, and specimen surface and volume affect substances release from materials.

CLINICAL RELEVANCE

It could be advisable to rely on materials based on monomers with a reduced elution tendency for clinical procedures.

Cytotoxic and Genotoxic Effects of Composite Resins on Cultured Human Gingival Fibroblasts

The aim of the study was to evaluate the cytotoxic and genotoxic potential of five commercially available dental composite resins (CRs), investigating the effect of their quantifiable bisphenol-A-glycidyl-methacrylate (Bis-GMA) and/or triethylene glycol dimethacrylate (TEGDMA) release. Experiments were performed using the method of soaking extracts, which were derived from the immersion of the following CRs in the culture medium: Clearfil-Majesty-ES-2, GrandioSO, and Enamel-plus-HRi (Bis-GMA-based); Enamel-BioFunction and VenusDiamond (Bis-GMA-free). Human Gingival Fibroblasts (hGDFs) were employed as the cellular model to mimic in vitro the oral cavity milieu, where CRs simultaneously release various components. Cell metabolic activity, oxidative stress, and genotoxicity were used as cellular outcomes. Results showed that only VenusDiamond and Enamel-plus-HRi significantly affected the hGDF cell metabolic activity. In accordance with this, although no CR-derived extract induced a significantly detectable oxidative stress, only VenusDiamond and Enamel-plus-HRi induced significant genotoxicity. Our findings showed, for the CRs employed, a cytotoxic and genotoxic potential that did not seem to depend only on the actual Bis-GMA or TEGDMA content. Enamel-BioFunction appeared optimal in terms of cytotoxicity, and similar findings were observed for Clearfil-Majesty-ES-2 despite their different Bis-GMA/TEGDMA release patterns. This suggested that simply excluding one specific monomer from the CR formulation might not steadily turn out as a successful approach for improving their biocompatibility.

Expression of pro-inflammatory cytokines and mediators induced by Bisphenol A via ERK-NFκB and JAK1/2-STAT3 pathways in macrophages

Macrophages not only play an important role in the innate immune response but also participate in many inflammatory and infectious diseases including asthma, diabetes, obesity, cardiovascular diseases, and cancers. Bisphenol A (BPA) is the most commonly used component for plastic products. However, BPA is an endocrine disruptor for mammals and participates in several inflammatory and infectious diseases. Up until now, there are no researches demonstrated the potential role of BPA in macrophage activation and its relative mechanism. BPA promoted the generation of proinflammatory cytokines IL-1β, IL-6, and TNFα in a concentration-dependent manner (P < 0.05). BPA was identified to increase the expression of proinflammatory mediators NO and PGE2, and its upstream factors iNOS, COX2, and cPLA2 in a concentration-dependent manner (P < 0.05). Phosphorylation and nuclear translocation of NF-κB p65 were significantly induced by BPA via IκB degradation (P < 0.05). In addition, phosphorylation of ERK significantly induced by BPA at a concentration which was less than that for phosphorylation of p38 MAPK and JNK (P < 0.05). Furthermore, phosphorylation of STAT3 significantly induced by BPA at a concentration lower than that for phosphorylation of STAT1 (P < 0.05). Phosphorylation of JAK1 and JAK2 was also significantly induced by BPA in a concentration-dependent manner (P < 0.05).

Evaluation of biofilm formation on novel copper-catalyzed azide-alkyne cycloaddition (CuAAC)-based resins for dental restoratives

OBJECTIVE

For the past several decades, the resins used in dental restorations have been plagued with numerous problems, including their implication in biofilm formation and secondary caries. The need for alternative resins is critical, and evaluation of biofilm formation on these resins is essential. The aim of this study was to evaluate in vitro biofilm formation on the surface of novel copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC)-based resins and composites.

METHODS

CuAAC-based resins/composites made from varying azide monomers and different copper concentrations were compared with BisGMA-TEGDMA resins/composites that served as the control. Biofilms were formed using a mono-species model containing a luciferase-expressing strain of Streptococcus mutans. Luciferase activity was measured and the number of viable bacteria was enumerated on biofilms associated with each resin and composite.

RESULTS

A significant reduction (p<0.05) in luciferase activity, and the number of viable bacteria recovered from biofilms on CuAAC-based resins and composites was observed in comparison to biofilms associated with the BisGMA-TEGDMA controls.

SIGNIFICANCE

CuAAC-based resins do still allow for the formation of biofilms; however, the statistically significant reduction of growth that was associated with the CuAAC resin may enhance the longevity of restorations that incorporate CuAAC-based materials.

Safrole induced cytotoxicity, DNA damage, and apoptosis in macrophages via reactive oxygen species generation and Akt phosphorylation

Safrole is a natural compound categorized as a group 2B carcinogen extracted from betel quid chewing, which is a common practice of psychoactive habits integrated into social and cultural ceremonies among serveral million people, especially in Southern or Southeastern Asia. Safrole is one of the major risk compunds for development of oral squamous cell carcinoma and hepatocellular carcinoma via DNA adduction. In innate immunity, macrophages are the predominant cells for non-specific first line defense against pathogens in oral tissue. Up to now, there is no evidence to implicate the potential toxicological effect of safrole on macrophages. In this study, we found safrole induced the generation of reactive oxygen species (ROS) and myeloperoxidase (MPO) in RAW264.7 macrophages in a concentration-dependent manner. Furthermore, cytotoxicity, DNA damage, and apoptosis were caused by safrole in a concentration-dependent manner. While the activation of antioxidative enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) was reduced, the phosphorylation of Akt was induced by safrole in a concentration-dependent manner. These results indicated that the induction of cytotoxicity, DNA damage, and apoptosis in macrophages by safrole was through generation of ROS and inhibition of antioxidative enzymes possibly via Akt phosphorylation.

Protective effect of wogonin on endotoxin-induced acute lung injury via reduction of p38 MAPK and JNK phosphorylation

Acute lung injury (ALI) is a serious inflammatory disorder which remains the primary cause of incidence and mortality in patients with acute pulmonary inflammation. However, there is still no effective medical strategy available clinically for the improvement of ALI. Wogonin, isolated from roots of Scutellaria baicalensis Georgi, is a common medicinal herb which presents biological and pharmacological effects, including antioxidation, anti-inflammation, and anticancer. Preadministration of wogonin inhibited not only lung edema but also protein leakage into the alveolar space in murine model of lipopolysaccharide (LPS)-induced ALI. Moreover, wogonin not only reduced the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 but also inhibited the phosphorylation of mitogen-activated protein kinase (MAPK) induced by LPS. We further found wogonin inhibited the phosphorylation of p38 MAPK and JNK at a concentration lower than ERK. In addition, inhibition of lung edema, protein leakage, expression of iNOS and COX-2, and phosphorylation of p38 MAPK and JNK were all observed in a parallel concentration-dependent manner. These results suggest that wogonin possesses potential protective effect against LPS-induced ALI via downregulation of iNOS and COX-2 expression by blocking phosphorylation of p38 MAPK and JNK. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 397-403, 2017.

Simvastatin and a Plant Galactolipid Protect Animals from Septic Shock by Regulating Oxylipin Mediator Dynamics through the MAPK-cPLA2 Signaling Pathway

Sepsis remains a major medical issue despite decades of research. Identification of important inflammatory cascades and key molecular mediators are crucial for developing intervention and prevention strategies. In this study, we conducted a comparative oxylipin metabolomics study to gain a comprehensive picture of lipid mediator dynamics during the initial hyperinflammatory phase of sepsis, and demonstrated, in parallel, the efficacy of simvastatin and plant galactolipid, 1,2-di-O-α-linolenoyl-3-O-β-galactopyranosyl-sn-glycerol (dLGG) in the homeostatic regulation of the oxylipin metabolome using a lipopolysaccharide (LPS)-induced sepsis C57BL/6J mouse model. LPS increased the systemic and organ levels of proinflammatory metabolites of linoleic acid including leukotoxin diols (9-,10-DHOME, 12-,13-DHOME) and octadecadienoic acids (9-HODE and 13-HODE) and arachidonic acid-derived prostanoid, PGE2, and hydroxyeicosatetraenoic acids (8-, 12- and 15-HETE). Treatment with either compound decreased the levels of proinflammatory metabolites and elevated proresolution lipoxin A₄, 5(6)-EET, 11(12)-EET and 15-deoxy-PGJ₂. dLGG and simvastatin ameliorated the effects of LPS-induced mitogen-activated protein kinase (MAPK)-dependent activation of cPLA₂, cyclooxygenase-2, lipoxygenase, cytochrome P450 and/or epoxide hydrolase lowered systemic TNF-α and IL-6 levels and aminotransferase activities and decreased organ-specific infiltration of inflammatory leukocytes and macrophages, and septic shock-induced multiple organ damage. Furthermore, both dLGG and simvastatin increased the survival rates in the cecal ligation and puncture (CLP) sepsis model. This study provides new insights into the role of oxylipins in sepsis pathogenesis and highlights the potential of simvastatin and dLGG in sepsis therapy and prevention.

BisGMA-induced cytotoxicity and genotoxicity in macrophages are attenuated by wogonin via reduction of intrinsic caspase pathway activation

Bisphenol-A-glycidyldimethacrylate (BisGMA) is a frequently used monomer in dental restorative resins. However, BisGMA could leach from dental restorative resins after polymerization leading to inflammation in the peripheral environment. Wogonin, a natural flavone derivative, has several benefits, such as antioxidative, anti-inflammatory and neuroprotective properties. Pretreatment of macrophage RAW264.7 cells with wogonin inhibited cytotoxicity which is induced by BisGMA in a concentration-dependent manner. BisGMA induced apoptotic responses, such as redistribution of phosphatidylserine from the internal to the external membrane and DNA fragmentation, were decreased by wogonin in a concentration-dependent manner. In addition, BisGMA-induced genotoxicity, which detected by cytokinesis-blocked micronucleus and single-cell gel electrophoresis assays, were inhibited by wogonin in a concentration-dependent manner. Furthermore, wogonin suppressed BisGMA-induced activation of intrinsic caspase pathways, such as caspases-3 and -8. Parallel trends were observed in inhibition of caspase-3 and -8 activities, apoptosis, and genotoxicity. These results indicate wogonin suppressed the BisGMA-induced apoptosis and genotoxicity mainly via intrinsic caspase pathway in macrophages.

N-acetyl cysteine protects human oral keratinocytes from Bis-GMA-induced apoptosis and cell cycle arrest by inhibiting reactive oxygen species-mediated mitochondrial dysfunction and the PI3K/Akt pathway

Bisphenol-A-glycidyl methacrylate (Bis-GMA) released from dental resin materials causes various toxic effects on gingival epithelium. Thus the underlying mechanisms of its cytotoxicity should be elucidated for safety use. One potential cause of cell damage is the generation of reactive oxygen species (ROS) beyond the capacity of a balanced redox regulation. In this study, we found that exposure of human oral keratinocytes (HOKs) to Bis-GMA caused apoptosis and G1/S cell cycle arrest in parallel with an increased ROS level. Moreover, Bis-GMA induced a depletion of mitochondrial membrane potential, an increase in the Bax/Bcl-2 ratio, an activation of caspase-3 and altered expressions of cell cycle-related proteins (p21, PCNA, cyclinD1). Furthermore, the co-treatment of the ROS scavenger N-acetyl cysteine (NAC) obviously attenuated Bis-GMA-induced toxicity. Here we also evaluated the effects of Bis-GMA on the ROS-related PI3k/Akt pathway. We found that Bis-GMA inhibited the phosphorylation of Akt, whereas the amount of phosphorylated Akt was reverted to the control level in the presence of NAC. Our findings suggested that the toxic effects of Bis-GMA were related to ROS production and the antioxidant NAC effectively reduced Bis-GMA-mediated cytotoxicity.

Anti-inflammation effect of methyl salicylate 2-O-β-D-lactoside on adjuvant induced-arthritis rats and lipopolysaccharide (LPS)-treated murine macrophages RAW264.7 cells

Methyl salicylate 2-O-β-D-lactoside (MSL) is a derivative of natural salicylate isolated from Gaultheria yunnanensis (Franch.) Rehder, which is widely used for treating rheumatoid arthritis (RA), swelling and pain. The aim of the present study was to investigate the effect of MSL on the progression of adjuvant-induced arthritis (AIA) in rat in vivo and explore the anti-inflammatory effects and mechanism of MSL in lipopolysaccharide (LPS)-treated murine macrophages RAW264.7 cells in vitro. Our results showed that MSL significantly inhibited the arthritis progression in AIA rats, decreasing the right hind paw swelling and ankle diameter, attenuating histopathological changes and suppressing the plasma levels of TNF-α and IL-1β in AIA rats. Besides, MSL had potent anti-inflammatory effects on the LPS-activated RAW264.7. MSL dose-dependently inhibited the activity of COX-1, and COX-2. Moreover, MSL prominently inhibited LPS-induced activation of MAPK in RAW264.7 cells by blocking phosphorylation of p38 and ERK. Our study suggests that MSL may be effective in the treatment of inflammatory diseases by inhibiting the pro-inflammatory cytokine production and regulating the MAPK signal pathway.