In vitro anti-inflammatory effect of picrasmalignan A by the inhibition of iNOS and COX‑2 expression in LPS‑activated macrophage RAW 264.7 cells

Lactobacillus plantarum LPYC225 mixture partially modulates the vaginal bacterial community of Gardnerella vaginalis-infected bacterial vaginosis in mice

Bacterial vaginosis (BV) is defined as dysbiosis of the vaginal microbiome associated with the depletion of Lactobacilli and excessive growth of commensal or pathogenic bacteria. This study investigated the effects of lactic acid bacteria (LAB) mixture (LM; InoRexyne™) on the vaginal bacterial community of Gardnerella vaginalis (G. vaginalis)-infected BV mice. Single LAB and LM exhibited antibacterial and anti-inflammatory effects by inhibiting G. vaginalis growth and pro-inflammatory markers in RAW 264.7 cells. Administering LM did not significantly alter the vaginal architecture or fecal short-chain fatty acids but did significantly inhibit the vaginal interleukin-6 levels in the high LM group compared to the GV group. LM administration decreased the relative abundances of Enterobacter, Escherichia coli, and Bacteroides vulgatus in vaginal flushing fluids compared to the GV group. LM partially alleviated BV by inhibiting G. vaginalis growth and modulating the vaginal bacterial community, providing new insights into its modulatory effects on the vaginal microbiome in BV.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-024-01641-w.

High Molecular Weight Fucoidan Restores Intestinal Integrity by Regulating Inflammation and Tight Junction Loss Induced by Methylglyoxal-Derived Hydroimidazolone-1

Fucoidan from brown seaweeds has several biological effects, including preserving intestinal integrity. To investigate the intestinal protective properties of high molecular weight fucoidan (HMWF) from Undaria pinnatifida on intestinal integrity dysfunction caused by methylglyoxal-derived hydroimidazolone-1 (MG-H1), one of the dietary advanced-glycation end products (dAGEs) in the human-colon carcinoma-cell line (Caco-2) cells and ICR mice. According to research, dAGEs may damage the intestinal barrier by increasing gut permeability. The findings of the study showed that HMWF + MG-H1 treatment reduced by 16.8% the amount of reactive oxygen species generated by MG-H1 treatment alone. Furthermore, HMWF + MGH-1 treatment reduced MG-H1-induced monolayer integrity disruption, as measured by alterations in transepithelial electrical resistance (135% vs. 75.5%) and fluorescein isothiocyanate incorporation (1.40 × 10^-6 cm/s vs. 3.80 cm/s). HMWF treatment prevented the MG-H1-induced expression of tight junction markers, including zonula occludens-1, occludin, and claudin-1 in Caco-2 cells and mouse colon tissues at the mRNA and protein level. Also, in Caco-2 and MG-H1-treated mice, HMWF plays an important role in preventing receptor for AGEs (RAGE)-mediated intestinal damage. In addition, HMWF inhibited the nuclear factor kappa B activation and its target genes leading to intestinal inflammation. These findings suggest that HMWF with price competitiveness could play an important role in preventing AGEs-induced intestinal barrier dysfunction.

Anti-Inflammatory Mechanism of An Alkaloid Rutaecarpine in LTA-Stimulated RAW 264.7 Cells: Pivotal Role on NF-κB and ERK/p38 Signaling Molecules

Lipoteichoic acid (LTA) is a key cell wall component and virulence factor of Gram-positive bacteria. LTA contributes a major role in infection and it mediates inflammatory responses in the host. Rutaecarpine, an indolopyridoquinazolinone alkaloid isolated from Evodia rutaecarpa, has shown a variety of fascinating biological properties such as anti-thrombotic, anticancer, anti-obesity and thermoregulatory, vasorelaxing activity. It has also potent effects on the cardiovascular and endocrine systems. Herein, we investigated rutaecarpine’s (Rut) anti-inflammatory effects in LTA-stimulated RAW macrophage cells. The Western blot and spectrophotometric results revealed that Rut inhibited the production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and interleukin (IL)-1β in the LTA-induced macrophage cells. Successively, our mechanistic studies publicized that Rut inhibited LTA-induced phosphorylation of mitogen-activated protein kinase (MAPK) including the extracellular signal-regulated kinase (ERK), and p38, but not c-Jun NH2-terminal kinase (JNK). In addition, the respective Western blot and confocal image analyses exhibited that Rut reserved nuclear transcription factor kappa-B (NF-κB) by hindering inhibitor of nuclear factor κB-α (IκBα) and NF-κB p65 phosphorylation and p65 nuclear translocation. These results indicate that Rut exhibits its anti-inflammatory effects mainly through attenuating NF-κB and ERK/p38 signaling pathways. Overall, this result suggests that Rut could be a potential therapeutic agent for the treatment of Gram-positive bacteria induced inflammatory diseases.

Alkaloids from Picrasma quassioides: An overview of their NMR data, biosynthetic pathways and pharmacological effects

Picrasma quassioides, a member of the Simaroubaceae family, is the subject of research in numerous pharmacological and chemical studies. This plant mainly contains alkaloids, quassinoids and terpenoids. These molecules exhibit various pharmacological benefits, such as anti-inflammatory, anticancer, and anti-viral effects, on the cardiovascular system. Alkaloids make up the majority of these molecules. This review describes 127 alkaloid substances from P. quassioides. These alkaloids can be divided into the following classes: β-carbolines, canthinones and alkaloid dimers. A compilation of their nuclear magnetic resonance spectroscopy data and possible biosynthetic pathways of these compounds and the pharmacological effects of P. quassioides are also included.

Pharmacological effects of Picrasma quassioides (D. Don) Benn for inflammation, cancer and neuroprotection (Review)

Picrasma quassioides (D. Don) Benn is an Asian shrub with a considerable history of traditional medicinal use. P. quassioides and its extracts exhibit good therapeutic properties against several diseases, including anti-inflammatory, antibacterial and anticancer effects. However, the composition of compounds contained in P. quassioides is complex; although various studies have examined mixtures or individual compounds extracted from it, studies on the application of P. quassioides extracts remain limited. In the present review, the structures and functions of the compounds identified from P. quassioides and their utility in anti-inflammatory, anticancer and neuroprotectant therapies was discussed. The present review provided up-to-date information on pharmacological activities and clinical applications for P. quassioides extracts.

Auraptene, a Monoterpene Coumarin, Inhibits LTA-Induced Inflammatory Mediators via Modulating NF-κB/MAPKs Signaling Pathways

Objective

Oxidative stress-mediated inflammatory events involve in the progress of several diseases such as asthma, cancers, and multiple sclerosis. Auraptene (AU), a natural prenyloxycoumarin, possesses numerous pharmacological activities. Here, the anti-inflammatory effects of AU were investigated in lipoteichoic acid- (LTA-) induced macrophage cells (RAW 264.7).

Methods

The expression of cyclooxygenase (COX-2), tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), and inducible nitric oxide synthase (iNOS) and the phosphorylation of extracellular signal-regulated kinase (ERK) 1/2, p38 MAPK, c-Jun N-terminal kinase (JNK), heme oxygenase (HO-1), p65, and IκBα were all identified by western blotting assay. The level of nitric oxide (NO) was measured by spectrometer analysis. The nuclear translocation of p65 nuclear factor kappa B (NF-κB) was assessed by the confocal microscopic staining method. Native polyacrylamide gel electrophoresis was performed to perceive the activity of antioxidant enzyme catalase (CAT).

Results

AU expressively reduced NO production and COX-2, TNF-α, IL-1 β, and iNOS expression in LTA-stimulated cells. AU at higher concentration (10 µM) inhibited ERK and JNK, but not p38 phosphorylation induced by LTA. Moreover, AU blocked IκB and p65 phosphorylation, and p65 nuclear translocation. However, AU pretreatment was not effective on antioxidant HO-1 expression, CAT activity, and reduced glutathione (GSH, a nonenzymatic antioxidant), in LTA-induced RAW 264.7 cells.

Conclusion

The findings of this study advocate that AU shows anti-inflammatory effects via reducing NF-κB/MAPKs signaling pathways.

Structure and pro-inflammatory activities of bran polysaccharides from a novel wheat kernel

In this study, the structure and pro-inflammatory activities of water-soluble wheat bran polysaccharides (WBP) were evaluated. WBP were heteropolysaccharides consisting 60.34% arabinoxylan as the main component and 31.80% mannose residues characterized with the instrumental analyses. The result of cellular experiment displayed that WBP had significant pro-inflammatory activities by increasing the concentration of nitric oxide (NO) and up-regulating the inflammatory cytokine expressions of inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α). WBP mediated macrophages RAW 264.7 pro-inflammatory response through phosphatidylinositol 3 hydroxykinase/protein kinase B (PI3K/Akt) signaling pathway by significantly promoting Akt and phosphoinositide-dependent kinase 1 (PDK1) phosphorylations. Meanwhile, the expression of related phosphorylated proteins JNK and ERK1/2 was significantly up-regulated which suggested that WBP played pro-inflammatory roles by activating mitogen-activated protein kinases (MAPKs) signaling pathway. PRACTICAL APPLICATIONS: In recent years, wheat bran generally has the phenomenon of high yield and low utilization rate. Wheat bran has rich nutritional value and contains a lot of effective biologically active substances. Based on our findings, the water-soluble polysaccharides extracted from wheat bran have significant effects on regulating immunity and can be utilized as sources of natural immune modulators. The research can develop new functions of wheat bran polysaccharides, and improve processing utilization rate and product added value.

Dehydrocrenatidine inhibits head and neck cancer cells invasion and migration by modulating JNK1/2 and ERK1/2 pathway and decreases MMP-2 expression

Head and neck cancer is associated with poor prognosis because of its highly metastatic nature. For the better management of head and neck cancer patients, it is very important to diagnose the cancer at an early stage, as well as to prevent the rapid spread of cancer either through direct invasion or lymphatic metastasis. In present study, the effect of dehydrocrenatidine, which is a beta-carboline alkaloid found in the medicinal plant Picrasma quassioides, on human head and neck cancer metastasis was investigated. The study results revealed the treatment of FaDu, SCC9, and SCC47 cells with 5, 10, and 20 μM of dehydrocrenatidine significantly decreased the motility, migration, and invasion of head and neck cancer cells. Moreover, the dehydrocrenatidine treatment significantly decreased the expression of MMP-2 and phosphorylation of ERK1/2 and JNK1/2. Additional experiments revealed that the cotreatment of dehydrocrenatidine with either ERK1/2 or JNK1/2 inhibitor caused further reduction in cancer cell motility and migration compared to that in dehydrocrenatidine treatment alone. Moreover, similar trend was observed in case of ERK1/2 and JNK1/2 phosphorylation and MMP-2 expression after the cotreatment. Taken together, the mechanism by which dehydrocrenatidine can decrease the phosphorylation of ERK1/2 and JNK1/2, follow decrease the expression of MMP-2 and inhibits head and neck cancer cells invasion and migration. This present study identifies dehydrocrenatidine as a potent antimetastatic agent that can be used clinically to improve head and neck cancer prognosis.

Apoptotic effects of dehydrocrenatidine via JNK and ERK pathway regulation in oral squamous cell carcinoma

Dehydrocrenatidine, a β-carboline alkaloid isolated from Picrasma quassioides, has been demonstrated to exert analgesic effects and play essential roles in janus kinase inhibition and exert analgesic effects through the suppression of neuronal excitability. Alkaloids such as paclitaxel and vincristine had been well explored to be chemotherapeutic agents. However, the anticancer effects of dehydrocrenatidine remain unclear. In the present study, we found that dehydrocrenatidine induced apoptosis in human oral cancer cells through both extrinsic and intrinsic pathways involving proteins such as caspase-3, caspase-8, caspase-9, poly (adenosine diphosphate-ribose) polymerase, and members of the Bcl-2 family. Cotreatment with dehydrocrenatidine and mitogen-activated protein kinase (MAPK) inhibitors indicated that dehydrocrenatidine induced apoptosis through the activation of extracellular signal-regulated kinases (ERK) and c-Jun N-terminal kinases (JNK). The findings provide insight into the potential of dehydrocrenatidine for a new perspective on molecular regulation.

Phytochemistry, Traditional Use and Pharmacological Activity of Picrasma quassioides: A Critical Reviews

Picrasma quassioides is a member of the Simaroubaceae family commonly grown in the regions of Asia, the Himalayas, and India and has been used as a traditional herbal medicine to treat various illnesses such as fever, gastric discomfort, and pediculosis. This study aims to critically review the presence of phytochemicals in P. quassioides and correlate their pharmacological activities with the significance of its use as traditional medicine. Data were collected by reviewing numerous scientific articles from several journal databases on the pharmacological activities of P. quassioides using certain keywords. As a result, approximately 94 phytochemicals extracted from P. quassioides were found to be associated with quassinoids, β-carbolines and canthinones. These molecules exhibited various pharmacological benefits such as anti-inflammatory, antioxidant, anti-cancer, anti-microbial, and anti-parasitic activities which help to treat different diseases. However, P. quassioides were also found to have several toxicity effects in high doses, although the evidence regarding these effects is limited in proving its safe use and efficacy as herbal medicine. Accordingly, while it can be concluded that P. quassioides may have many potential pharmacological benefits with more phytochemistry discoveries, further research is required to determine its real value in terms of quality, safety, and efficacy of use.

Ethyl acetate extract of herpetospermum pedunculosum alleviates α-naphthylisothiocyanate-induced cholestasis by activating the farnesoid x receptor and suppressing oxidative stress and inflammation in rats

BACKGROUND

Traditionally, seeds of Herpetospermum pedunculosum were used to treat liver disease or cholepathy. Up to date, their protecting effect against cholestasis was remain unclarified.

PURPOSE

To investigate the efficacy, possible mechanisms, and active constituents of the ethyl acetate extract from the seeds of Herpetospermum pedunculosum (HPEAE), studies were carried out using cholestasis rat model induced by α-naphthylisothiocyanate (ANIT).

METHODS

Male rats were intragastrically treated with HPEAE (100, 200 or 400 mg/kg) once a day for 7 days and were modeled with ANIT (60 mg/kg). The levels of serum indicators, bile flow, and histopathology were evaluated. Indices of oxidative stress and inflammatory mediators were detected using the enzyme-linked immunosorbent assay. Western blotting method was employed for analyzing the protein levels in the signal pathways of farnesoid X receptor (FXR), kelch ech associating protein 1/nuclear factor erythroid 2-related factor 2 (Keap1/Nrf2) and nuclear factor κB (NF-κB). The chemical compositions of HPEAE was analyzed by HPLC, and partially chemical components of HPEAE were identified by comparisons of their retention times with the standards. The FXR agonistic activity of the identified compounds was evaluated in l-02 cells induced by guggulsterone using a high-content screening system.

RESULTS

The cholestasis caused by ANIT can be significantly ameliorated by restoring the liver function indexes of alanine transaminase, aspartate transaminase, alkaline phosphatase, gamma-glutamyltransferase, total bilirubin, direct bilirubin and total bile acid, which are dose-dependent, as well as pathological liver injury and bile flow. Mechanical studies suggested that HPEAE can activate the expression of FXR and then up regulate its downstream proteins (multidrug resistance-associated protein 2, bile salt export pump and Na+/taurocholate cotransporting polypeptide). Moreover, the levels of the active oxygen index glutathione, superoxide dismutase, glutathione peroxidase, catalase and malondialdehyde were markedly restored by treatment with HPEAE. Western blotting further confirmed that HPEAE up regulated the expression of quinone oxidoreductase 1, heme oxygenase 1 and Keap1, lowered the expression of Nrf2 and reduced oxidative stress. HPEAE also up regulated P-glycoprotein 65, phosphorylated P-glycoprotein 65 and inhibitor of NF-κB kinase α expression, down regulated inhibitor of NF-κB (IκB), restored inflammatory mediator tumor necrosis factor-α, interleukin-1β (IL-1β), IL-6 and IL-10, and reduced inflammatory response. Fifteen compounds were identified (12 lignans and 3 coumarins). Among them, five lignans exhibited the significant FXR agonistic activity in vitro.

CONCLUSION

HPEAE may alleviate the cholestasis and liver injury caused by ANIT in rats by activating FXR, as well as suppressing the Keap1/Nrf2 and NF-κB signaling pathways and lignans may be its main active components.

Gastric protective activities of fucoidan from brown alga Kjellmaniella crassifolia through the NF-κB signaling pathway

Fucoidan has been reported to have abundant biological activities. The objective of the present study was to detect the protective effects of fucoidan from Kjellmaniella crassifolia (KF) newly cultured in Dalian, North of China on aspirin-induced gastric ulcers of the Wistar rat model. The present study showed that inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and IL-10 were effectively regulated in rats pretreated with KF. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities increased significantly in the KF pretreated groups, while the levels of maleic dialdehyde (MDA) decreased. The findings obtained by RT-PCR and western blotting indicated that KF could suppress aspirin-induced NF-κB activation via stabilization of IκB-α and thereby induced the downregulation of COX-2 and iNOS. It was demonstrated that KF exerted positive gastric protective effects via suppression of the inflammatory response and oxidative stress, and the mechanism of KF appeared to mediate the NF-κB signaling pathway.

Discrimination of Naturally-Occurring 2-Arylbenzofurans as Cyclooxygenase-2 Inhibitors: Insights into the Binding Mode and Enzymatic Inhibitory Activity

2-arylbenzofuran-containing compounds are chemical entities that can be naturally produced by several organisms. A wide-range of activities is described for several compounds of this kind and they are, therefore, valuable moieties for a lead finding from nature. Although there are in-vitro data about the activity of 2-arylbenzofuran-related compounds against cyclooxygenase (COX) enzymes, the molecular level of these COX-inhibiting constituents had not been deeply explored. Thus, 58 2-arylbenzofurans were initially screened through molecular docking within the active site of nine COX-2 crystal structures. The resulting docking scores were statistically analyzed and good reproducibility and convergence were found to discriminate the best-docked compounds. Discriminated compounds exhibited the best performance in molecular dynamics simulations as well as the most-favorable binding energies and the lowest in-vitro IC50 values for COX-2 inhibition. A three-dimensional quantitative activity-structure relationship (3D-QSAR) was also demonstrated, which showed some crucial structural requirements for enhanced enzyme inhibition. Therefore, four hits are proposed as lead structures for the development of COX-2 inhibitors based on 2-arylbenzofurans in further studies.

Dehydrocrenatidine Inhibits Voltage-Gated Sodium Channels and Ameliorates Mechanic Allodia in a Rat Model of Neuropathic Pain

Picrasma quassioides (D. Don) Benn, a medical plant, is used in clinic to treat inflammation, pain, sore throat, and eczema. The alkaloids are the main active components in P. quassioides. In this study, we examined the analgesic effect of dehydrocrenatidine (DHCT), a β-carboline alkaloid abundantly found in P. quassioides in a neuropathic pain rat model of a sciatic nerve chronic constriction injury. DHCT dose-dependently attenuated the mechanic allodynia. In acutely isolated dorsal root ganglion, DHCT completely suppressed the action potential firing. Further electrophysiological characterization demonstrated that DHCT suppressed both tetrodotoxin-resistant (TTX-R) and sensitive (TTX-S) voltage-gated sodium channel (VGSC) currents with IC50 values of 12.36 μM and 4.87 µM, respectively. DHCT shifted half-maximal voltage (V1/2) of inactivation to hyperpolarizing direction by ~16.7 mV in TTX-S VGSCs. In TTX-R VGSCs, DHCT shifted V1/2 of inactivation voltage to hyperpolarizing direction and V1/2 of activation voltage to more depolarizing potential by ~23.9 mV and ~12.2 mV, respectively. DHCT preferred to interact with an inactivated state of VGSCs and prolonged the repriming time in both TTX-S and TTX-R VGSCs, transiting the channels into a slow inactivated state from a fast inactivated state. Considered together, these data demonstrated that the analgesic effect of DHCT was likely though the inhibition of neuronal excitability.

Identification of β-carboline and canthinone alkaloids as anti-inflammatory agents but with different inhibitory profile on the expression of iNOS and COX-2 in lipopolysaccharide-activated RAW 264.7 macrophages

A compound library, which consists of 75 natural β-carboline-type or canthinone-type alkaloids from Simaroubaceae plants and their chemical synthetic analogues, was screened for the anti-inflammatory activity by inhibition of the overproduction of inflammatory mediator nitric oxide (NO) in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells. Six compounds, namely, benzalharman (23), kumujian (27), 1-ethyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (37), 1-acetophenone-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (42), cathin-6-one (46), and 9-methoxy-cathin-6-one (57), exhibited significant inhibitory activity on the overproduction of NO with good dose dependency. Further investigation demonstrated that all of the six compounds down-regulated the high expression of inducible nitric oxide synthase (iNOS) protein. Among them, two canthinone-type alkaloids (46 and 57) potently down-regulated cyclooxygenase-2 (COX-2) protein expression in a dose-dependent manner and also inhibited the overproduction of inflammatory mediator prostaglandin E₂ (PGE₂). However, the β-carboline-type alkaloids (23, 27, 37, and 42) exhibited no obvious inhibition on the overproduction of PGE₂ and the expression of COX-2 protein. The results suggested that β-carboline-type alkaloids and canthinone-type alkaloids may exert an anti-inflammatory effect through different mechanism.

The promotion of tissue engineering blood vessel patency by CGS21680 through regulating pro-inflammatory activities of endothelial progenitor cell

The mobilization and homing of endothelial progenitor cells (EPCs) contribute to the rapid endothelialization of tissue engineering blood vessel (TEBV). Inflammation can affect TEBV patency, and monocytes/macrophages (MM) are the main effector cells. But it is not clear how EPCs interact with MM after TEBV transplantation. Our results showed acellular materials would not directly cause acute and severe inflammatory responses but activate E-selectin expression in homing EPCs, gradually promoting the polarization of MM to the M1. Adenosine A2a receptor agonist CGS21680 promoted the secretion of more proangiogenic factors from MM, inducing EPC migration and mobilization. CGS21680 could inhibit MM polarization to the M1 type through the down-regulation of EPC proinflammatory molecules, such as E-selectin. Chitosan/(2-hydroxypropyl)-β-cyclodextrin nanoparticles were prepared to control the release of CGS-21680 and then modified to TEBVs through layer-by-layer assembly. Animal experiments showed that this TEBV can maintain patency for 6 months and good endothelialization was observed. In summary, our results showed the regulation of EPC pro-inflammatory activities is a new approach to enhance TEBV patency. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2634-2642, 2018.

GM1 Induced the inflammatory response related to the Raf-1/MEK1/2/ERK1/2 pathway in co-culture of pig mesenchymal stem cells with RAW264.7

Pig-human xenotransplantation can trigger cell-mediated immune responses. We explored the role of gangliosides in inflammation related to immune rejection in xenotransplantation. Co-culture of xenogeneic cells (pig-MSCs and RAW264.7) was used to emulate xenotransplantation conditions. MTT assay results indicated that cell viability was significantly decreased in pADMSCs co-cultured with RAW264.7 cells. GM1 and GM3 were highly expressed in pADMSCs co-cultured with RAW264.7 cells. pADMSCs co-cultured with RAW264.7 cells strongly expressed pro-inflammatory proteins such as COX-2, iNOS, p50, p65, pIκBα, and TNF-α. GM1-knockdown pADMSCs co-cultured with RAW 264.7 cells did not show significantly altered cell viability, but pro-inflammatory proteins were markedly inhibited. Co-culture of pADMSCs with RAW264.7 cells induced significant phosphorylation (p) of JNK1/2 and pERK1/2. However, pERK1/2 and pJNK1/2 were decreased and MEK1/2 and Raf1 were suppressed in GM1-knockdown pADMSCs co-cultured with RAW264.7 cells. Thus, the Raf-1/MEK1/2/ERK1/2 and JNK1/2 pathways were significantly upregulated in response to increases of GM1 in co-cultured xenogeneic cells. However, the inflammatory response was suppressed in co-culture of GM1-knockdown pADMSCs with RAW264.7 cells via down-regulation of the Raf-1/MEK1/2/ERK1/2 and JNK1/2 pathways. Therefore, the ganglioside GM1 appears to play a major role in the inflammatory response in xenotransplantation via the Raf-1/MEK1/2/ERK1/2 and JNK1/2 pathways.

Ginkgolide A Ameliorates LPS-Induced Inflammatory Responses In Vitro and In Vivo

Ginkgolide A (GA) is a natural compound isolated from Ginkgo biloba and has been used to treat cardiovascular diseases and diabetic vascular complications. However, only a few studies have been conducted on the anti-inflammatory effects of GA. In particular, no related reports have been published in a common inflammation model of lipopolysaccharide (LPS)-stimulated macrophages, and the anti-inflammatory mechanisms of GA have not been fully elucidated. In the present study, we extensively investigated the anti-inflammatory potential of GA in vitro and in vivo. We showed that GA could suppress the expression of pro-inflammatory mediators (cyclooxygenase-2 (COX-2) and nitric oxide (NO) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β) in LPS-treated mouse peritoneal macrophages, mouse macrophage RAW264.7 cells, and differentiated human monocytes (dTHP-1) in vitro. These effects were partially carried out via downregulating Nuclear factor kappa-B (NF-κB), Mitogen-activated protein kinases (MAPKs) (p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (ERK), but not c-Jun N-terminal kinase (JNK), and activating the AMP-activated protein kinase (AMPK) signaling pathway also seems to be important. Consistently, GA was also shown to inhibit the LPS-stimulated release of TNF-α and IL-6 in mice. Taken together, these findings suggest that GA can serve as an effective inflammatory inhibitor in vitro and in vivo.

Anti-inflammatory and Anti-oxidative Activities of Paeonol and Its Metabolites Through Blocking MAPK/ERK/p38 Signaling Pathway

The possible protective and curative effects of paeonol on carrageenan-induced acute hind paw edema in rats and dextran sulfate sodium (DSS)-induced colitis in mice have been evaluated. After oral administration, paeonol (20 and 40 mg/kg) reduced the edema increase in paw volumes and also the development of DSS-induced murine colitis. Furthermore, anti-inflammatory and anti-oxidant activities of paeonol (1) together with its 10 metabolites (M2~M11) were investigated by using in vitro anti-inflammatory and anti-oxidant assays. M3 and M11 exhibited significant 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities (with EC50 values of 93.44 and 23.24 μM, respectively). All the metabolites except M8 showed hydroxyl radical scavenging activities, and M3 and M11 were the most potent agents (with EC50 values of 336.02 and 124.05 μM, respectively). Inhibitory effects of paeonol, M2~M11 on the overproduction of nitric oxide (NO), and the release of TNF-α were also tested. M3 and M11 potently inhibited lipopolysaccharide (LPS)-induced overproduction of NO in macrophage RAW 264.7. Western blot results demonstrated that paeonol, M3, and M11 downregulated the high expression of inducible nitric oxide synthase (iNOS) and COX-2 proteins, and the effects of M3 and M11 were more potent when compared with paeonol. These findings indicated that paeonol may play anti-inflammatory and anti-oxidant roles by changing to its active metabolites after absorption. In addition, further investigations on the mechanism showed that paeonol, M3, and M11 blocked the phosphorylation of MAPK/ERK 1/2 and p38, whereas they showed no effect on the phosphorylation of JNK. The above results suggested that pre-treatment with paeonol might be an effective therapeutic intervention against inflammatory diseases including colitis.