Heme oxygenase-1 mediates the inhibitory actions of brazilin in RAW264.7 macrophages stimulated with lipopolysaccharide

Chemoenzymatic formal synthesis of (+)-brazilin

Herein, the manuscript presents a chemoenzymatic formal synthetic route of (+)-brazilin, a homoisoflavonoid natural product with a chroman skeleton cis-fused with a 2,3-dihydro-1H-indene unit, which is isolated from the traditional Chinese medicine, Caesalpinia sappan L. The key feature of the synthetic strategy includes an enzyme-mediated desymmetrization by employing lipase from Candida antarctica type B (CALB) and a one-pot SN2/hydrolysis reaction.

Immune response enhancement by dietary supplementation with Caesalpinia sappan extract in weaned pigs challenged with porcine reproductive and respiratory syndrome virus

BACKGROUND

At present, porcine reproductive and respiratory syndrome (PRRS) caused by the PRRS virus (PRRSV) is one of the most severe epidemics impacting pig farming globally. Despite the fact that a number of studies have been conducted on potential solutions to this problem, none have proven effective. The focus of problem solving is the use of natural ingredients such as plant extracts. Popular throughout Asia, Caesalpinia sappan (CS) is a therapeutic plant that inhibits PRRSV in vitro. Therefore, this study was performed to determine the efficacy of CS extract dietary supplementation on the productive performance, antibody levels, immunological indicators, and lung pathology of PRRSV-challenged weaned pigs. A total of 32 weaned piglets (28 days old) were randomized into 4 groups and kept separately for 14 days. The treatments were organized in a 2 × 2 factorial design involving two factors: PRRSV challenge and supplementation with 1 mg/kg CS extract. The pigs in the PRRSV-challenged groups were intranasally inoculated with 2 mL of PRRSV (VR2332) containing 104 TCID50/mL, while those in the groups not challenged with PRRSV were inoculated with 2 mL of normal saline.

RESULTS

In the PRRSV-challenged group (CS + PRRSV), supplementation with CS extract led to an increase in white blood cells (WBCs) on Day 7 post infection (p < 0.05) and particularly in lymphocytes on Days 7 and 14. The antibody titer was significantly greater in the CS + PRRSV group than in the PRRSV-challenged group not administered CS (PRRSV group) on Day 14 postinfection (S/P = 1.19 vs. 0.78). In addition, CS extract administration decreased the prevalence of pulmonary lesions, which were more prevalent in the PRRSV-challenged pigs that did not receive the CS extract.

CONCLUSION

The findings of this study suggest that supplementation with CS extract is beneficial for increasing WBC counts, especially lymphocytes, increasing the levels of antibodies and reducing the prevalence of lung lesions in PRRSV-infected pigs.

Brazilin is a natural product inhibitor of the NLRP3 inflammasome

Excessive or aberrant NLRP3 inflammasome activation has been implicated in the progression and initiation of many inflammatory conditions; however, currently no NLRP3 inflammasome inhibitors have been approved for therapeutic use in the clinic. Here we have identified that the natural product brazilin effectively inhibits both priming and activation of the NLRP3 inflammasome in cultured murine macrophages, a human iPSC microglial cell line and in a mouse model of acute peritoneal inflammation. Through computational modeling, we predict that brazilin can adopt a favorable binding pose within a site of the NLRP3 protein which is essential for its conformational activation. Our results not only encourage further evaluation of brazilin as a therapeutic agent for NLRP3-related inflammatory diseases, but also introduce this small-molecule as a promising scaffold structure for the development of derivative NLRP3 inhibitor compounds.

Effects of Dietary Supplementation with Caesalpinia sappan Linn. Extract for Promoting Flock Health and Performance in Late-Phase Laying Hens

The present study investigated the effects of dietary supplementation of Caesalpinia sappan Linn Extract (CSE) on the health and productive performance of late-phase laying hens on farms. Proximate composition and antioxidant markers of CSE powder revealed favorable characteristics with high total dry matter; phenolic content, and antioxidant potency. Three hundred and sixty (64-week-old) Hy-line Brown hens were divided into five groups with 0 (control diet), 250, 500, 1000, and 2000 mg/kg CSE, respectively. The laying performance and egg quality of the CSE supplementation groups demonstrated significant improvements in egg weight and albumin weight (p < 0.05), and a tendency for enhanced egg mass and feed conversion ratio. Additionally, the intestinal morphostructural indices in the 2000 mg CSE/kg diet group showed the greatest statistical significance (p < 0.05), with a detectable trend suggesting an increase in the villus height to crypt depth ratio. In addition, significant downregulation of proinflammatory genes occurred in their liver tissues, coupled with a greater expression of genes linked to antioxidants and anti-inflammatory processes. Furthermore, the blood biochemical parameters and the organ weights may suggest a favorable safety profile of CSE supplementation. These findings highlight the potential of CSE as a dietary supplement to enhance the productive performance and flock health of late-phase laying hens. Further research is warranted to explore the long-term effects and optimal dosage of CSE supplementation for laying hens in farming practices.

A Comprehensive Review on Bioactive Compounds Found in Caesalpinia sappan

Sappan wood (Caesalpinia sappan) is a tropical hardwood tree found in Southeast Asia. Sappan wood contains a water-soluble compound, which imparts a red color named brazilin. Sappan wood is utilized to produce dye for fabric and coloring agents for food and beverages, such as wine and meat. As a valuable medicinal plant, the tree is also known for its antioxidant, anti-inflammatory, and anticancer properties. It has been observed that sappan wood contains various bioactive compounds, including brazilin, brazilein, sappan chalcone, and protosappanin A. It has also been discovered that these substances have various health advantages; they lower inflammation, enhance blood circulation, and are anti-oxidative in nature. Sappan wood has been used as a medicine to address a range of illnesses, such as gastrointestinal problems, respiratory infections, and skin conditions. Studies have also suggested that sappan wood may have anticarcinogenic potential as it possesses cytotoxic activity against cancer cells. Based on this, the present review emphasized the different medicinal properties, the role of phytochemicals, their health benefits, and several food and nonfood applications of sappan wood. Overall, sappan wood has demonstrated promising medicinal properties and is an important resource in traditional medicine. The present review has explored the potential role of sappan wood as an essential source of bioactive compounds for drug development.

Analytical determination, antioxidant and anti-inflammatory activities of Bhamrung-Lohit a traditional Thai medicine

Background and purpose

Bhamrung-Lohit (BRL) remedy is a traditional Thai medicine (TTM). There are few reports of biological activity, the activity of its constituent plants, or quantitative analytical methods for the content of phytochemicals. In this study, we investigated antioxidant, anti-inflammatory activity, and total phenolic and flavonoid content and validated a new analytical method for BRL.

Experimental approach

Antioxidant activity was evaluated by a 2,2-diphenyl-1-picrylhydrazyl (DPPH and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging. The cellular antioxidant activity was evaluated by inhibition of the superoxide anion (O2●-) production from HL-60 cells and anti-inflammatory activity by inhibition of nitric oxide production in RAW264.7 cells. The total phenolic and flavonoid contents were analyzed using the Folin-Ciocalteu method and an aluminum chloride colorimetric assay, respectively. Validated analytical procedures were conducted according to International Conference on Harmonization (ICH) guidelines.

Findings/Results

An ethanolic extract of BRL exerted potent DPPH radical scavenging activity and moderate antioxidant and anti-inflammatory activity. Caesalpinia sappan exerted the greatest effect and the highest content of total phenolics and flavonoids. The HPLC method validated parameters that complied with ICH requirements. Each peak showed selectivity with a baseline resolution of 2.0 and precision was less than 2.0% CV. The linearity of all compounds was > 0.999 and the recovery % was within 98.0%-102.0%. The validated results demonstrated specificity/selectivity, linearity, precision, and accuracy with appropriate LOD and LOQ.

Conclusion and implication

BRL remedy, a TTM demonstrated antioxidant and anti-inflammatory properties. This study is the first report on the biological activity and the validation of an HPLC method for BRL remedy.

Antibacterial Activity against Foodborne Pathogens and Inhibitory Effect on Anti-Inflammatory Mediators' Production of Brazilin-Enriched Extract from Caesalpinia sappan Linn

Caesalpinia sappan L. heartwood was collected from Mae Chaem District, Chiang Mai Province, Thailand. Crude extracts were prepared by Soxhlet’s extraction using 50, 60, and 70% of ethanol (EtOH) at 50, 60, and 70 °C, and the brazilin content was measured using reversed-phase high performance liquid chromatography (RP-HPLC). The antibacterial activity against foodborne pathogens and anti-inflammatory aspects were investigated. C. sappan, prepared from 70% EtOH at 70 °C (E70T70), significantly (p < 0.05) exhibited the highest amount of brazilin (7.90 ± 0.50% w/w). All extracts were investigated for anti-inflammatory activity through an inhibition effect on nitric oxide (NO) and inducible nitric oxide synthase (iNOS) production in RAW264.7 mouse macrophage cells. The inhibitory effect on cyclooxygenase-2 (COX-2) production in HT-29 and HCT116 was also studied. All the extracts inhibited NO, iNOS, and COX-2 production induced by combined lipopolysaccharide and interferon-γ, especially E70T70, indicating the highest inhibition effect among other extracts. Additionally, E70T70 was selected to determine the antibacterial activity against foodborne pathogens, including Staphylococcus aureus, Escherichia coli, Salmonella enteritidis, and Vibrio parahaemolyticus. The result showed that 200 µg/mL extract reduced all test pathogens 100% at 24 h. These results suggested the potential of using C. sappan L. extract as a natural preservative in food and a natural active pharmaceutical ingredient.

Deoxyhypusine hydroxylase as a novel pharmacological target for ischemic stroke via inducing a unique post-translational hypusination modification

Ischemic stroke remains one of the leading causes of death worldwide, thereby highlighting the urgent necessary to identify new therapeutic targets. Deoxyhypusine hydroxylase (DOHH) is a fundamental enzyme catalyzing a unique posttranslational hypusination modification of eukaryotic translation initiation factor 5A (eIF5A) and is highly involved in the progression of several human diseases, including HIV-1 infection, cancer, malaria, and diabetes. However, the potential therapeutic role of pharmacological regulation of DOHH in ischemic stroke is still poorly understood. Our study first discovered a natural small-molecule brazilin (BZ) with an obvious neuroprotective effect against oxygen-glucose deprivation/reperfusion insult. Then, DOHH was identified as a crucial cellular target of BZ using HuProt™ human proteome microarray. By selectively binding to the Cys232 residue, BZ induced a previously undisclosed allosteric effect to significantly increase DOHH catalytic activity. Furthermore, BZ-mediated DOHH activation amplified mitophagy for mitochondrial function and morphology maintenance via DOHH/eIF5A hypusination signaling pathway, thereby protecting against ischemic neuronal injury in vitro and in vivo. Collectively, our study first identified DOHH as a previously unreported therapeutic target for ischemic stroke, and provided a future drug design direction for DOHH allosteric activators using BZ as a novel molecular template.

Brazilin: Biological activities and therapeutic potential in chronic degenerative diseases and cancer

Caesalpinia sappan and Haematoxylum brasiletto belong to the Fabaceae family, predominantly distributed in Southeast Asia and America. The isoflavonoid brazilin has been identified from the bark and heartwood of these plants. This review summarizes the studies describing the biological activities of these plants and brazilin. Mainly, brazilin protects cells from oxidative stress, shows anti-inflammatory and antibacterial properties, and hypoglycemic effect. In addition, it has a biological impact on various pathologies such as Alzheimer's disease, Parkinson's disease, fibrillogenesis, and osteoarthritis. Interestingly, most of the antecedents are related to the anticancer effect of brazilin. In several cancers such as osteosarcoma, neuroblastoma, multiple myeloma, glioblastoma, bladder, melanoma, breast, tongue, colon, cervical, head, and neck squamous cell carcinoma, brazilin induces autophagy by increasing the levels of the LC3-II protein. Furthermore, it inhibits cell proliferation and induces apoptosis through increased expression of Bcl-2, Bcl-XL, p21, p27, activation of caspase-3 and -7, and the cleavage of PARP and inhibiting the expression of Bax. In addition, it blocks the expression of JNK and regulates the nuclear translocation of Nrf2. Together, these data positions brazilin as a compound of natural origin with multiple bioactivities and therapeutic potential in various chronic degenerative diseases and cancer.

Effect of Ethanolic Caesalpinia sappan Fraction on In Vitro Antiviral Activity against Porcine Reproductive and Respiratory Syndrome Virus

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major epidemic in pig production, leading to economic losses in the pig industry worldwide. The use of medicinal plants with antiviral properties might be useful help to prevent and control PRRSV outbreaks. Caesalpinia sappan (CS) heartwood is an important herbal ingredient used in Thai folk medicine, possessing various biological activities, including antiviral activity. The present study focuses on the in vitro antiviral activity against PRRSV of a semi-purified fraction of ethanolic CS crude extract using preparative high-performance liquid chromatography. Qualification of the fractions illustrating positive antiviral activity was carried out with liquid chromatography–quadrupole time-of-flight mass spectrometry. The preparative chromatography separated the crude extract into six consecutive fractions, among which the first fraction showed potential antiviral activity by inhibiting PRRSV replication in a MARC-145 monolayer (virus titer 2.75 median tissue culture infective dose (TCID₅₀)/mL (log₁₀) vs. 9.50 median log10 TCID₅₀/mL of the control) at 72 h post-infection, and this fraction included byakangelicin, brazilin, naringenin, and brazilein. These results provide useful information for further study to effectively develop the CS bioactive antiviral compounds against PRRSV as a feed additive or veterinary drug in the pig industry.

Chondroprotection and Molecular Mechanism of Action of Phytonutraceuticals on Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease and an important cause of incapacitation. There is a lack of drugs and effective treatments that stop or slow the OA progression. Modern pharmacological treatments, such as analgesics, have analgesic effects but do not affect the course of OA. Long-term use of these drugs can lead to serious side effects. Given the OA nature, it is likely that lifelong treatment will be required to stop or slow its progression. Therefore, there is an urgent need for disease-modifying OA treatments that are also safe for clinical use over long periods. Phytonutraceuticals are herbal products that provide a therapeutic effect, including disease prevention, which not only have favorable safety characteristics but may have an alleviating effect on the OA and its symptoms. An estimated 47% of OA patients use alternative drugs, including phytonutraceuticals. The review studies the efficacy and action mechanism of widely used phytonutraceuticals, analyzes the available experimental and clinical data on the effect of some phytonutraceuticals (phytoflavonoids, polyphenols, and bioflavonoids) on OA, and examines the known molecular effect and the possibility of their use for chondroprotection.

Integrative Bioinformatics Analysis Reveals Potential Target Genes and TNFα Signaling Inhibition by Brazilin in Metastatic Breast Cancer Cells

OBJECTIVE

Metastasis is the most significant cause of morbidity and mortality in breast cancer patients. Previously, a combination of brazilin and doxorubicin has been shown to inhibit metastasis in HER2-positive breast cancer cells. This present study used an integrative bioinformatics approach to identify new targets and the molecular mechanism of brazilin in inhibiting metastasis in breast cancer.

METHODS

Cytotoxicity and mRNA arrays data were retreived from the DTP website, whereas genes that regulate metastatic breast cancer cells were retreived from PubMed with keywords "breast cancer metastasis". Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, and Drug association analysis were carried out by using WEB-based GEne SeT AnaLysis Toolkit (WebGestalt). Construction of protein-protein interaction (PPI) network analysis was performed by STRING-DB v11.0 and Cytoscape, respectively. The genetic alterations of the potential therapeutic target genes of brazilin (PB) were analyzed using cBioPortal.

RESULTS

Analysis of cytotoxicity with the public database of COMPARE showed that brazilin exerts almost the same cytotoxicity in the NCI-60 cells panel showing by similar GI50 value, in which the lowest GI50 value was observed in MDA-MB 231, a metastatic breast cancer cells. KEGG enrichment indicated several pathways regulated by brazilin such as TNF signaling pathway, cellular senescence, and pathways in cancer. We found ten drugs that are associated with PB, including protein kinase inhibitors, TNFα inhibitors, enzyme inhibitors, and anti-inflammatory agents.

CONCLUSION

In conclusion, this study identified eight PB, including MMP14, PTGS2, ADAM17, PTEN, CCL2, PIK3CB, MAP3K8, and CXCL3. In addition, brazilin possibly inhibits metastatic breast cancer through inhibition of TNFα signaling. The study results study need to be validated with in vitro and in vivo studies to strengthen scientific evidence of the use of brazilin in breast cancer metastasis inhibition.

Brazilin Treatment Produces Antidepressant- and Anxiolytic-Like Effects in Mice

Increasing evidence shows depression relevant to oxidative stress and inflammation. Anti-inflammatory strategies or antioxidants have led to the development of new antidepressants. Brazilin is a natural product from the Chinese traditional medicine Caesalpinia sappan L., exerting anti-inflammatory, antioxidant, anti-platelet concentration, and anti-cancer effects. While the antidepressant effect of brazilin is largely unknown. In present study, we investigated the effects of brazilin on H₂O₂-induced oxidative injury in PC12 cells and on depression- and anxiety-like behaviors of chronically mild stressed (CMS)-induced depression mice. It was found that brazilin pre-treatment (both 10 and 20 µM) significantly increased cell viability and decreased cell apoptosis in H₂O₂-treated PC12 cells. Furthermore, repetitive administration of brazilin to CMS-induced depression mice by intraperitoneal injection (10 mg/kg) made the mice significantly lose their latency of feeding in novelty-suppressed feeding test (NSF), have more the sucrose preference in sucrose preference test (SPT), and more time spent in the central zone without affecting their crossing activity in open field test (OFT). These results suggested that brazilin can play a role in antidepressant and anxiolytic-like behaviors for CMS-induced depression mice probably through inhibiting the oxidative stress. Therefore, brazilin is worth to be further explored for treating depressive and anxiety disorders.

Anti-inflammatory activity of the extracts from Rodgersia podophylla leaves through activation of Nrf2/HO-1 pathway, and inhibition of NF-κB and MAPKs pathway in mouse macrophage cells

OBJECTIVE

Recently, Rodgersia podophylla has been reported to exhibit anti-inflammatory activity. However, little is known about the potential mechanisms about its anti-inflammatory activity. We elucidated the anti-inflammatory mechanisms of leaves extracts from Rodgersia podophylla (RP-L) in RAW264.7 cells.

MATERIALS AND METHODS

LPS-induced NO was measured by Griess and mRNA of pro-inflammatory mediators was analyzed by RT-PCR. Cell viability was measured using MTT assay. The protein level was analyzed by Western blot.

RESULTS

RP-L significantly inhibited the production of the pro-inflammatory mediators such as NO, iNOS, IL-1β and IL-6 in LPS-stimulated RAW264.7 cells. RP-L increased HO-1 expression in RAW264.7 cells, and the inhibition of HO-1 by ZnPP reduced the inhibitory effect of RP-L against LPS-induced NO production in RAW264.7 cells. Inhibition of p38, ROS and GSK3β attenuated RP-L-mediated HO-1 expression. Inhibition of ROS inhibited p38 phosphorylation and GSK3β expression induced by RP-L. In addition, inhibition of GSK3β blocked RP-L-mediated p38 phosphorylation. RP-L induced nuclear accumulation of Nrf2, and inhibition of p38, ROS and GSK3β abolished RP-L-mediated nuclear accumulation of Nrf2. Furthermore, RP-L blocked LPS-induced degradation of IκB-α and nuclear accumulation of p65. RP-L also attenuated LPS-induced phosphorylation of ERK1/2 and p38. In GC/MS analysis of RP-L, pyrogallol was detected as bioactive compound for anti-inflammatory activity of RP-L. Pyrogallol was observed to activate HO-1 expression through ROS/GSK3β/p38/Nrf2/HO-1 signaling.

CONCLUSIONS

Our results suggest that RP-L exerts potential anti-inflammatory activity by activating ROS/GSK3β/p38/Nrf2/HO-1 signaling and inhibiting NF-κB and MAPK signaling in RAW264.7 cells. These findings suggest that RP-L may have great potential for the development of anti-inflammatory drug.

Heracleum moellendorffii roots inhibit the production of pro-inflammatory mediators through the inhibition of NF-κB and MAPK signaling, and activation of ROS/Nrf2/HO-1 signaling in LPS-stimulated RAW264.7 cells

BACKGROUND

Heracleum moellendorffii roots (HM-R) have been long treated for inflammatory diseases such as arthritis, backache and fever. However, an anti-inflammatory effect and the specific mechanism of HM-R were not yet clear. In this study, we for the first time explored the anti-inflammatory of HM-R.

METHODS

The cytotoxicity of HM-R against RAW264.7 cells was evaluated using MTT assay. The inhibition of NO and PGE₂ production by HM-R was evaluated using Griess reagent and Prostaglandin E₂ ELISA Kit, respectively. The changes in mRNA or protein level following HM-R treatment were assessed by RT-PCR and Western blot analysis, respectively.

RESULTS

HM-R dose-dependently blocked LPS-induced NO and PGE₂ production. In addition, HM-R inhibited LPS-induced overexpression of iNOS, COX-2, IL-1β and IL-6 in RAW264.7 cells. HM-R inhibited LPS-induced NF-κB signaling activation through blocking IκB-α degradation and p65 nuclear accumulation. Furthermore, HM-R inhibited MAPK signaling activation by attenuating the phosphorylation of ERK1/2, p38 and JNK. HM-R increased nuclear accumulation of Nrf2 and HO-1 expression. However, NAC reduced the increased nuclear accumulation of Nrf2 and HO-1 expression by HM-R. In HPLC analysis, falcarinol was detected from HM-R as an anti-inflammatory compound.

CONCLUSIONS

These results indicate that HM-R may exert anti-inflammatory activity by inhibiting NF-κB and MAPK signaling, and activating ROS/Nrf2/HO-1 signaling. These findings suggest that HM-R has a potential as a natural material for the development of anti-inflammatory drugs.

Madecassoside ameliorates lipopolysaccharide-induced neurotoxicity in rats by activating the Nrf2-HO-1 pathway

Neuroinflammation is a predisposing factor for several neurodegenerative diseases. The purpose of this study was to evaluate the protective effect of madecassoside (MA) in lipopolysaccharide (LPS)-induced cognitive impairment and neuroinflammation in rats. MA has many protective effects such as antioxidant and anti-inflammatory properties. We investigated whether MA could improve neurocognitive dysfunction caused by intracerebroventricular injection of LPS. We examined the effects and mechanisms of action of MA on LPS-induced neuroinflammation in the cortex and hippocampus. Our study revealed that MA (120 mg/kg, i.g) treatment for 14 days reduced LPS-induced neurotoxicity by reducing cognitive impairments and suppressing the production of inflammatory cytokines such as interleukin 1 beta (IL-1β), tumor necrosis factor alpha(TNF-α), and interleukin 6(IL-6) via activation of nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. Furthermore, MA treatment enhanced protein levels of heme oxygenase (HO)-1 by upregulating Nrf2 in LPS-stimulated neurotoxicity. Collectively, these results suggest that MA is effective in preventing neurodegenerative diseases by improving memory functions due to its anti-inflammatory activities and activation of Keap1-Nrf2/HO-1 signaling. As such, MA may be a potential therapy for addressing memory impairment caused by neuroinflammation.

Sageretia thea Inhibits Inflammation through Suppression of NF-κB and MAPK and Activation of Nrf2/HO-1 Signaling Pathways in RAW264.7 Cells

Sageretia thea (S. thea) commonly known as Chinese sweet plum or Chinese bird plum has been used for treating hepatitis and fevers in Korea and China. S. thea has been reported to exert anti-oxidant, anticancer and anti-human immunodeficiency virus activity. However, there is little study on the anti-inflammatory activity of S. thea. Thus, we evaluated the anti-inflammatory effect of extracts of leaves (ST-L) and branches (ST-B) from Sageretia thea in LPS-stimulated RAW264.7 cells. ST-L and ST-B significantly inhibited the production of the pro-inflammatory mediators such as NO, iNOS, COX-2, IL-1[Formula: see text] and IL-6 in LPS-stimulated RAW264.7 cells. ST-L and ST-B blocked LPS-induced degradation of I[Formula: see text]B-[Formula: see text] and nuclear accumulation of p65, which resulted in the inhibition of NF-[Formula: see text]B activation in RAW264.7 cells. ST-L and ST-B also attenuated the phosphorylation of ERK1/2, p38 and JNK in LPS-stimulated RAW264.7 cells. In addition, ST-L and ST-B increased HO-1 expression in RAW264.7 cells, and the inhibition of HO-1 by ZnPP reduced the inhibitory effect of ST-L and ST-B against LPS-induced NO production in RAW264.7 cells. Inhibition of p38 activation and ROS elimination attenuated HO-1 expression by ST-L and ST-B, and ROS elimination inhibited p38 activation induced by ST-L and ST-B. ST-L and ST-B dramatically induced nuclear accumulation of Nrf2, but this was significantly reversed by the inhibition of p38 activation and ROS elimination. Collectively, our results suggest that ST-L and ST-B exerts potential anti-inflammatory activity by suppressing NF-[Formula: see text]B and MAPK signaling activation, and activating HO-1 expression through the nuclear accumulation of Nrf2 via ROS-dependent p38 activation. These findings suggest that ST-L and ST-B may have great potential for the development of anti-inflammatory drug to treat acute and chronic inflammatory disorders.

Madecassoside prevents acute liver failure in LPS/D-GalN-induced mice by inhibiting p38/NF-κB and activating Nrf2/HO-1 signaling

Madecassoside (MA), a triterpenoid saponin isolated from Centella asiatica, exerts various pharmacological activities including antioxidative and anti-inflammatory effects. The aim of this study was to explore the protective effect of MA in the treatment of lipopolysaccharide (LPS) and D-galactosamine (D-GalN)-induced acute liver failure(ALF) in mice. We hypothesized that MA administration may decrease the degree of liver injury caused by LPS/D-GalN. In this study, we investigated this hypothesis by treating a mouse model of LPS/D-GalN-induced liver injury with MA. Our study demonstrated that MA (20 mg/kg and 40 mg/kg) treatment for 10 days attenuated LPS/D-GalN-induced liver injury by protecting liver function, suppressing the production of inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, and recovering antioxidant enzyme activity. MA also significantly suppressed LPS-stimulated protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 by blocking the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and eukaryotic transcription factor nuclear factor-kappa B (NF-κB). In addition, MA treatment enhanced protein levels of heme oxygenase (HO)-1 and anti-oxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) through the upregulation of nuclear factor E2-related factor 2 (Nrf2) in LPS-stimulated liver injury. These results suggest that MA is a promising agent for the treatment of LPS/D-GalN-induced liver injury that could serve as a candidate for the development of a hepatoprotective drug against ALF.

Synthesis and biological activity of new phthalimides as potential anti-inflammatory agents

The overproduction of nitric oxide (NO) plays an important role in a variety of pathophysiological processes, including inflammation. Therefore, the suppression of NO production is a promising target in the design of anti-inflammatory agents. In the present study, a series of phthalimide analogs was synthesized, and their anti-inflammatory activities were evaluated using lipopolysaccharide (LPS)-stimulated NO production in cultured murine macrophage RAW264.7 cells. A structure-activity relationship study showed that the free hydroxyl group at C-4 and C-6 and the bulkiness of the N-substituted alkyl chain are associated with biological activity. Among the series of phthalimide derivatives, compound IIh exhibited potent inhibitory activity, with an IC₅₀ value of 8.7µg/mL. Further study revealed that the inhibitory activity of compound IIh was correlated with the down-regulation of the mRNA and protein expression of LPS-stimulated inducible nitric oxide synthase (iNOS). Compound IIh also suppressed the induction of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β in LPS-stimulated RAW 264.7 cells. The anti-inflammatory activity of compound IIh was also found to be associated with the suppression of the Toll-like receptor (TLR)4 signaling pathway by down-regulating the activation of interferon regulatory factor 3 (IRF-3) and interferon-β and signal transducer expression. These findings demonstrate that novel phthalimides might be potential candidates for the development of anti-inflammatory agents.

Involvement of Nrf2-mediated heme oxygenase-1 expression in anti-inflammatory action of chitosan oligosaccharides through MAPK activation in murine macrophages

Chitosan and its derivatives have been reported to have anti-inflammatory effects in vitro and in vivo. It is also suggested that chitosan and its derivatives could be up-regulating heme oxygenase-1 (HO-1) in different models. However, the up-regulation of HO-1 by chitosan oligosaccharides (COS) remains unexplored in regard to anti-inflammatory action in lipopolysaccharide (LPS)-stimulated murine macrophages (RAW264.7 cells). Treatment with COS induced HO-1 expression in LPS-stimulated RAW264.7 cells, whereas the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was decreased. Pretreatment with ZnPP, a HO-1 inhibitor, reduced the COS-mediated anti-inflammatory action. HO-1 induction is mediated by activating the nuclear translocation of NF-E2-related factor 2 (Nrf2) using COS. Moreover, COS increased the phosphorylation of extracellular signal regulated kinase (ERK1/2), c-Jun N-terminal kinase/stress-activated protein kinase (JNK), and p38 MAPK. However, specific inhibitors of ERK, JNK, and p38 reduced COS-mediated nuclear translocation of Nrf2. Therefore, HO-1 induction also decreased in RAW264.7 cells. Collectively, COS exert an anti-inflammatory effect through Nrf2/MAPK-mediated HO-1 induction.

Brazilin exerts protective effects against renal ischemia-reperfusion injury by inhibiting the NF-κB signaling pathway

Renal ischemia-reperfusion (I/R) injury is associated with high morbidity and mortality as there is currently no available effective therapeutic strategy with which to treat this injury. Thus, the aim of this study was to investigate the potential protective effects of brazilin, a major active component of the Chinese medicine Caesalpinia sappan L., against renal I/R injury in vitro and in vivo. Rats were subjected to removal of the right kidney and I/R injury to the left kidney (ischemia for 45 min followed by reperfusion for 24 h). Treatment with brazilin (30 mg/kg, administered intravenously at 30 min prior to ischemia) led to the reversal of I/R-induced changes in serum creatinine (Scr) and blood urea nitrogen (BUN) levels, and also attenuated the histopathological damage induced by I/R. Furthermore, TUNEL assay revealed that brazilin reduced cell necrosis, and significantly decreased the expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1β in renal tissue. Moreover, HK-2 cells were used in order to elucidate the mechanisms responsible for the protective effects of brazilin. The levels of phosphorylated IκBα and the nuclear translocation of nuclear factor-κB (NF-κB) were all evidently decreased by brazilin. These findings suggested that pre-treatment with brazilin protects against I/R-induced renal damage and suppresses the inflammatory response by inhibiting the activation of the NF-κB signaling pathway.

Compounds from Caesalpinia sappan with anti-inflammatory properties in macrophages and chondrocytes

The heartwood of Caesalpinia sappan is a traditional ingredient of food and beverages in South East Asia and has been used in traditional medicine as an analgesic and anti-inflammatory drug or to promote blood circulation.

Anti-inflammatory effects of Saururus chinensis aerial parts in murine macrophages via induction of heme oxygenase-1

Saururus chinensis (Lour.) Baill. is a perennial plant distributed throughout Northeast Asia and its roots have been widely used as a traditional medicine for hepatitis, asthma, pneumonia, and gonorrhea. This study was designed to investigate the anti-inflammatory activity of an extract of S. chinensis of the aerial parts (rather than the root), and the signaling pathway responsible for this effect in lipopolysaccharide-stimulated murine macrophages. The subfraction 4 (SCF4) from the n-hexane layer of the ethanol extract of the aerial parts of S. chinensis exhibited the highest nitrite-inhibitory activity. SCF4 significantly inhibited the production of nitrite and the expression of pro-inflammatory mediators via heme oxygenase-1 upregulation. SCF4 caused significant phosphorylation of p38 MAPK and Akt, which subsequently induced the nuclear translocation of p-p65 nuclear factor-κB and Nrf2. SCF4 also suppressed the phosphorylation of signal transducers and activators of transcription 1 (p-STAT1). The heme oxygenase-1 inhibitor zinc protoporphyrin attenuated the inhibitory effect of SCF4 on lipopolysaccharide-stimulated nitrite production and expression of inflammatory mediators, tumor necrosis factor alpha, and p-STAT1. We identified sauchinone as the active compound in S. chinensis extract and SCF4. Sauchinone was shown to significantly inhibit nitrite production and inflammatory mediators expression via heme oxygenase-1 upregulation. These results suggest that S. chinensis extract, SCF4, and its active compound, sauchinone, could be used as an anti-inflammatory agent.

Brazilin isolated from the heartwood of Caesalpinia sappan L induces endothelium-dependent and -independent relaxation of rat aortic rings

AIM

Brazilin is one of the major constituents of Caesalpinia sappan L with various biological activities. This study sought to investigate the vasorelaxant effect of brazilin on isolated rat thoracic aorta and explore the underlying mechanisms.

METHODS

Endothelium-intact and -denuded aortic rings were prepared from rats. The tension of the preparations was recorded isometrically with a force displacement transducer connected to a polygraph. The phosphorylation levels of ERK1/2 and myosin light chain (MLC) were analyzed using Western blotting assay.

RESULTS

Application of brazilin (10-100 μmol/L) dose-dependently relaxed the NE- or high K(+)-induced sustained contraction of endothelium-intact aortic rings (the EC50 was 83.51±5.6 and 79.79±4.57 μmol/L, respectively). The vasorelaxant effect of brazilin was significantly attenuated by endothelium removal or by pre-incubation with L-NAME, methylene blue or indomethacin. In addition, pre-incubation with brazilin dose-dependently attenuated the vasoconstriction induced by KCl, NE or Ang II. Pre-incubation with brazilin also markedly suppressed the high K(+)-induced extracellular Ca(2+) influx and NE-induced intracellular Ca(2+) release in endothelium-denuded aortic rings. Pre-incubation with brazilin dose-dependently inhibited the NE-stimulated phosphorylation of ERK1/2 and MLC in both endothelium-intact and -denuded aortic rings.

CONCLUSION

Brazilin induces relaxation in rat aortic rings via both endothelium-dependent and -independent ways as well as inhibiting NE-stimulated phosphorylation of ERK1/2 and MLC. Brazilin also attenuates vasoconstriction via blocking voltage- and receptor-operated Ca(2+) channels.

Spiranthes sinensis Suppresses Production of Pro-Inflammatory Mediators by Down-Regulating the NF-κB Signaling Pathway and Up-Regulating HO-1/Nrf2 Anti-Oxidant Protein

Spiranthes sinensis is an east Asian wild orchid used in Chinese folk medicine. In this study, an ethyl acetate fraction from S. sinensis(SSE) was found to suppress the production of LPS-stimulated inflammatory mediators in RAW264.7 cells and BALB/c mice. SSE inhibited the production of pro-inflammatory mediators such as nitric oxide (NO), prostaglandin E2 (PGE2), tumo necrosis factor-α (TNF-α), IL-1β, and IL-6 in LPS-stimulated RAW264.7 cells. SSE also significantly suppressed LPS-stimulated protein levels of iNOS and mPGES-1 by blocking IκB phosphorylation, NF-κB nuclear translocation, and MAPKs phosphorylation. In addition, SSE treatment also enhanced protein levels of HO-1 and anti-oxidant enzymes (SOD-1, CAT, and GPx-1) through the nuclear translocation of Nrf2 in LPS-stimulated RAW264.7 cells. In vivo, we demonstrated that SSE attenuated the levels of pro-inflammatory mediators (NO, TNF-α, IL-1β, and IL-6), ALT, and AST in the serum of LPS-stimulated BALB/c mice. Western blotting revealed that SSE enhanced HO-1 expression in lung and liver tissue after LPS injection in mice. These results suggest that the anti-inflammatory properties of SSE involve the suppression of iNOS, mPGES-1, and inflammatory mediators by inducing the HO-1 pathway in LPS-stimulated RAW264.7 cells and BALB/c mice.

Evaluation of Su Fu'ning Lotion's Inhibitory Effects on Bladder Cancer Cells In Vitro and In Vivo by Intravesical Instillation

BACKGROUND

Bladder cancer is a common malignant tumor with a very high recurrence rate after surgery. Intravesical instillation can help clear up the residual tumor cells after surgery and thereby reduce the recurrence rate.

OBJECTIVE

To establish a bladder tumor transplantation animal model and to evaluate the inhibitory effects of a novel perfusate, Su Fu'ning Lotion (SFN), on bladder tumor.

METHODS

SFN was compared with several commonly used chemotherapy drugs, including mitomycin (MMC) and pirarubicin (THP) for anticancer effects on the bladder cancer cell lines T24, BTT, and BIU-87 and SFN half inhibitory concentrations (IC50) were determined after 48 hours of treatment. In addition, bladder cancer orthotopic transplantation tumor models were established in BALB/C nude mice and T739 mice, and SFN anticancer effects were assessed in vivo, with normal saline and MMC as negative and positive controls, respectively.

RESULTS

SFN, MMC, and THP were all lethal to bladder cancer cells, in vitro, with SFN and THP significantly superior to MMC. IC50 values for SFN were 13.22, 11.22, and 12.5 µg/mL on T24, BTT, and BIU-87 cells, respectively. In vivo, SFN significantly reduced the mouse bladder wet weight and prolonged the animal survival compared with controls (P < .05), suggesting that SFN significantly inhibited T24/BTT cell growth in mice.

CONCLUSION

SFN inhibited the bladder cancer cell proliferation in vitro and in vivo and significantly prolonged the survival of mice with bladder cancer xenografts, indicating that SFN could be used as a perfusate after surgery for removal of residual bladder cancers cells.

Brazilin from Caesalpinia sappan heartwood and its pharmacological activities: A review

Caesalpinia sappan L. (CS) is a plant of Leguminosae family, commonly known as Brazil or Sappan wood. CS is distributed in Southeast Asia and its dried heartwood has been used as traditional ingredient of food or beverages and has a wide variety of medicinal properties. Higher extraction yield of CS wood was achieved with 95% ethanol for 2 h. Chemical constituent's investigation of sappan wood resulted in the isolation of various structural types of phenolic components including one xanthone, one coumarin, three chalcones, two flavones three homoisoflavonoids and brazilin. Brazilin [(6a S-cis)-7, 11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10(6H)- tetrol], a major and active compound found in CS heartwood. Most of the folkloric uses of brazilin were validated by the scientific studies such as antioxidant, antibacterial, anti-inflammatory, anti-photoaging, hypoglycemic, vasorelaxant, hepatoprotective and anti-acne activity. CS heartwood extract is safe and did not produce any acute or subacute toxicity in both male and female rats. Brazilin is the safe natural compound having potential to develop as a medicinal compound with application in food, beverage, cosmetics and pharmaceutical industries to screen its clinical use in modern medicine. The information gained could provide the important and potential approach for pharmaceutical researcher to implicate the knowledge of brazilin in the formulation of new drug and to reveal therapeutic and gaps requiring future research opportunities. More studies are needed to evaluate the potential application of brazilin as preservative and coloring agent in food processing industries.

Polygonum viviparum L. induces vasorelaxation in the rat thoracic aorta via activation of nitric oxide synthase in endothelial cells

Background

In the past several decades, Polygonum viviparum L. (PV) was reported to have antibacterial, antiulcer, antioxidant, antitumor, anti-inflammatory, and antiarthritic properties. The anti-inflammatory pathway was recently elucidated through cytosolic nuclear factor E2-related factor 2 (Nrf2) activation and heme oxygenase (HO)-1 protein expression. PV is a perennial herb and widely distributed in high-elevation mountain regions, such as the Tibetan Plateau. In Tibetan traditional medicine, PV is usually used to boost the blood circulation to dissipate blood stasis. Therefore, this study focused on how PV improves the vascular circulation and acts on vascular tissues.

Methods

In this study, we isolated aortas from Sprague-Dawley rats (male, weight about 250 ~ 350 g), and detected the effects of PV on phenylephrine (PE)-induced contraction and cyclic guanosine 3′,5′-monophosphate (cGMP) formation using aortic rings. In addition, human umbilical vein endothelial cells (HUVECs) were used to exam nitric oxygen (NO) synthase (NOS) activity by directly measuring NO production in the culture medium. Endothelial (e) NOS phosphorylation, and cytosolic Nrf2 and HO-1 expressions were measured using a Western blot analysis.

Results

PV dose-dependently relaxed PE-induced contractions in endothelial-intact but not -denuded aorta. The concentration to produce 50% relaxation was 22.04 ± 1.77 μg/ml. PV-induced vasorelaxation was markedly blocked by pretreatment with N^G-nitro-_L-arginine methyl ester (L-NAME), an NOS inhibitor, methylene blue (MB), a guanylyl cyclase inhibitor, and hemoglobin, an NO scavenger. PV increased cGMP formation; however, this effect was also suppressed by co-pretreatment with l-NAME, MB, hemoglobin, and Ca²⁺-free medium. In HUVECs, PV increased NO formation, which was greatly attenuated by NOS inhibitors (L-NAME and L-NMMA) and by removing extracellular Ca²⁺ and chelating intracellular Ca²⁺ with BAPTA-AM. In addition, PV promoted eNOS phosphorylation, Nrf2 degradation, and HO-1 protein expression according to a Western blot analysis.

Conclusions

The results suggest that PV possesses vasorelaxing action in an endothelium-dependent manner and works through activating Ca²⁺/calmodulin- dependent NO synthesis; when NO is released and then transferred to smooth muscle cells, NO activates guanylyl cyclase and increases cGMP formation, ultimately resulting in vasorelaxation. Thus, PV can be considered for application as a potential therapeutic approach for vascular-associated disorders.

A simple high-performance liquid chromatographic method for the determination of brazilin and its application to a pharmacokinetic study in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Caesalpinia sappan is a medicinal plant native to China popularly used to treat chronic pelvic inflammation, dysmenorrhea and hysteromyoma. Its main bioactive component is brazilin which had presented antibacterial, anti-inflammatory and anti-platelet aggregation activities. To establish a sensitive, selective, reproducible, and accurate high performance liquid chromatographic (HPLC) method for the quantitative determination of brazilin in plasma, and study the pharmacokinetics of brazilin in rats after intravenous administration of brazilin.

MATERIALS AND METHODS

Rats received intravenous injection of 25, 50 and 100mg/kg of brazilin. Concentrations of brazilin in plasma were determined by HPLC method at different time points and all pharmacokinetic parameters were estimated by non-compartmental analysis with WinNonLin 6.2 software.

RESULTS

After single intravenous doses of 25, 50 and 100mg/kg brazilin in rats, the main PK parameters were as follows: Cmax were 18.1 ± 4.1, 46.7 ± 8.7 and 82.2 ± 9.6 µg/mL; AUC0-24 were 20.4 ± 4.3, 48.7 ± 6.8 and 90.4 ± 10.3 µgh/mL; and t1/2 were 5.4 ± 1.5, 5.8 ± 0.9 and 6.2 ± 1.2h, respectively.

CONCLUSION

It showed that the brazilin was eliminated moderately in rat by intravenous injection route with t1/2 of 6h and showed a dose-dependence profile of Cmax and AUC0-24 at the doses of 25~100mg/kg of brazilin for injection in rats.

Identification of active compounds from Caesalpinia sappan L. extracts suppressing IL-6 production in RAW 264.7 cells by PLS

ETHNOPHARMACOLOGICAL RELEVANCE

Caesalpinia sappan L. is distributed in Southeast Asia and also used as herbal medicine for the treatment of various diseases such as burning sensations, leprosy, dysentery, osteoarthritis and rheumatoid arthritis (RA). The overproduction of IL-6 plays an important role in the prognosis of RA, but the active compounds from the extracts of Caesalpinia sappan L. suppressing IL-6 production remain unknown.

AIMS OF THE STUDY

Identifying the main active compounds of Caesalpinia sappan L. extracts inhibiting the IL-6 production in LPS-stimulated RAW 264.7 cells by partial least squares (PLS).

MATERIALS AND METHODS

Sixty-four samples with different proportions of compounds were prepared from Caesalpinia sappan L. by supercritical CO2 fluid extraction (SCFE) and refluxing. Each of 64 samples was applied to RAW 264.7 cells with LPS to evaluate whether IL-6 production by LPS is affected by addition of each sample. The IL-6 production in medium was determined by ELISA and the inhibitory activity of each sample was analyzed. In addition, the fingerprints of these 64 samples were also established by ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-MS). We used the PLS, a simplified method, to evaluate the results from IL-6 production and fingerprints.

RESULTS

Each of 64 samples markedly suppressed LPS-induced IL-6 production in RAW cells. The fingerprints by UPLC-MS clearly revealed variations among 64 samples produced in different extract conditions. The PLS analysis with IL-6 production and fingerprints by UPLC-MS suggested that the peaks 71, 93, 150, 157, 168 have more influence on the inhibitory activity of Caesalpinia sappan L. extracts. The peaks 71, 93, 150 are likely representing sappanone A, protosappanin E and neoprotosappanin, respectively. The peaks 157 and 168 are still at large.

CONCLUSION

This is the first report that sappanone A, protosappanin E, neoprotosappanin and two unidentified compounds can be considered as possible active compounds that might inhibit IL-6 production. Further studies are needed to confirm the effectiveness of these five compounds on IL-6 production and possible mechanism.

Application of a liquid chromatography-tandem mass spectrometry method to the pharmacokinetics, tissue distribution and excretion studies of brazilin in rats

Brazilin is an important constituent of Caesalpinia sappan L., and has several bioactivities. In this study, a rapid and sensitive analytical method based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has been developed for the determination of brazilin in rat plasma, urine, feces and tissues (brain, heart, liver, lung and kidney and spleen). Biological samples were processed with ethyl acetate containing 5% formic acid extraction, and salicylic acid (SA) was chosen as the internal standard (IS). The separation of brazilin was achieved on an Inspire C18 column (4.6mm×150mm, 5μm) with a mobile phase consisting of methanol/5mM ammonium acetate (80:20, v/v). The MS/MS detection was carried out by monitoring the fragmentation of m/z 285.1→163.0 for brazilin and m/z 137.1→93.1 for SA on a triple quadrupole mass spectrometer. The total run time was only 5.0min. The analyte showed good linearity over a wide concentration range (R(2)>0.995) and its lower limit of quantification was 2ng/mL. The accuracy and precision ranged from 97.1 to 103.3% and 1.7 to 9.1%, respectively. Recoveries (78.9-93.8%) and matrix effects (81.0-97.8%) were satisfactory in all the biological matrices examined. Stability studies (86.4-99.8%) showed that brazilin was stable during the assay procedure and long-term storage. The assay was successfully applied to plasma pharmacokinetics, tissue distribution and excretion study of rats. The pharmacokinetic parameters, such as half-life, mean residence time, maximum concentration were determined. These preclinical data of brazilin would be useful for the clinical reference.

Polygonum viviparum L. inhibits the lipopolysaccharide-induced inflammatory response in RAW264.7 macrophages through haem oxygenase-1 induction and activation of the Nrf2 pathway

BACKGROUND

Polygonum viviparum L. (PV) is a member of the family Polygonaceae and is widely distributed in high-elevation areas. It is used as a folk remedy to treat inflammation-related diseases. This study was focused on the anti-inflammatory response of PV against lipopolysaccharide (LPS)-induced inflammation in RAW264.7 macrophages.

RESULTS

Treatment with PV did not cause cytotoxicity at 0-50 µg mL(-1) in RAW264.7 macrophages, and the IC(50) value was 270 µg mL(-1). PV inhibited LPS-stimulated nitric oxide (NO), prostaglandin (PG)E(2) , interleukin (IL)-1β and tumour necrosis factor (TNF)-α release and inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 protein expression. In addition, PV suppressed the LPS-induced p65 expression of nuclear factor (NF)-κB, which is associated with the inhibition of IκB-α degradation. These results suggest that, among mechanisms of the anti-inflammatory response, PV inhibits the production of NO and these cytokines by down-regulating iNOS and COX-2 gene expression. Furthermore, PV can induce haem oxygenase (HO)-1 protein expression through nuclear factor E2-related factor 2 (Nrf2) activation. A specific inhibitor of HO-1, zinc(II) protoporphyrin IX, inhibited the suppression of iNOS and COX-2 expression by PV.

CONCLUSION

These results suggest that PV possesses anti-inflammatory actions in macrophages and works through a novel mechanism involving Nrf2 actions and HO-1. Thus PV could be considered for application as a potential therapeutic approach for inflammation-associated disorders.

Suppressive effects of Indigofera suffruticosa Mill extracts on lipopolysaccharide-induced inflammatory responses in murine RAW 264.7 macrophages

Indigofera suffruticosa Mill is used as an herbal medicine for the treatment of inflammation. The aim of this study is to assess the anti-inflammatory potency of I. suffruticosa and its likely molecular mechanisms of action in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Both water and ethanolic extracts of I. suffruticosa significantly decreased LPS-induced nitric oxide (NO) as well as the expression of inducible nitric oxide synthase (iNOS), tumor necrosis factor-α, and pro-interleukin-1β. Moreover, LPS-induced inhibitory factor-κB-α phosphorylation, nuclear factor-κB (NF-κB) nuclear protein-DNA binding affinity, and NF-κB reporter gene activity were dramatically inhibited by I. suffruticosa extracts. Exogenous addition of I. suffruticosa significantly induced heme oxygenase-1 (HO-1) expression, and the presence of HO-1 small interfering RNA partly reversed the inhibitory effects of I. suffruticosa on LPS-induced NO production and iNOS expression. Furthermore, I. suffruticosa induced HO-1 expression may be through activation of the ERK/nuclear factor E2-related factor 2 pathway. Eight phenolic compounds were found in the I. suffruticosa extracts, but salicylic acid was the only one detected in the plasma of mice fed with I. suffruticosa extracts. In summary, I. suffruticosa have a strong anti-inflammatory property that diminishes pro-inflammatory mediator expressions by lessening LPS-induced NF-κB activation and inducing HO-1 expression in macrophages.

Anti-inflammatory activity of an ethanolic Caesalpinia sappan extract in human chondrocytes and macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

Caesalpinia sappan is a common remedy in Traditional Chinese Medicine and possesses diverse biological activities including anti-inflammatory properties. Osteoarthritis (OA) is a degenerative joint disease with an inflammatory component that drives the degradation of cartilage extracellular matrix. In order to provide a scientific basis for the applicability of Caesalpinia sappan in arthritic diseases, the present study aimed to assess the effects of an ethanolic Caesalpinia sappan extract (CSE) on human chondrocytes and macrophages.

MATERIALS AND METHODS

Primary human chondrocytes were isolated from cartilage specimens of OA patients. Primary cells, SW1353 chondrocytes and THP-1 macrophages were serum-starved and pretreated with different concentrations of CSE prior to stimulation with 10 ng/ml of interleukin-1beta (IL-1β) or lipopolysaccharide (LPS). Following viability tests, nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α) were evaluated by Griess assay and ELISA, respectively. Using validated real-time PCR assays, mRNA levels of IL-1β, TNF-α, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were quantified. SW1353 cells were cotransfected with a COX-2 luciferase reporter plasmid and nuclear factor-kappa-B (NF-κB) p50 and p65 expression vectors in the presence or absence of CSE.

RESULTS

CSE dose-dependently inhibited the expression of pro-inflammatory cytokines IL-1β and TNF-α in IL-1β-stimulated chondrocytes and LPS-stimulated THP-1 macrophages. CSE further suppressed the synthesis of NO in primary OA chondrocytes by blocking iNOS mRNA expression. The inhibition of COX-2 transcription was found to be related with the CSE inhibition of the p65/p50-driven transactivation of the COX-2 promoter.

CONCLUSIONS

The present report is first to demonstrate the anti-inflammatory activity of CSE in an in vitro cell model of joint inflammation. CSE can effectively abrogate the IL-1β-induced over-expression of inflammatory mediators at the transcriptional level in human chondrocytes and macrophages, most likely by inhibiting NF-κB (p65/p50) signaling. Blockade of IL-1β-induced NF-κB signaling and its downstream pro-inflammatory targets by CSE may be beneficial for reducing cartilage breakdown in arthritis.

Myrrh mediates haem oxygenase-1 expression to suppress the lipopolysaccharide-induced inflammatory response in RAW264.7 macrophages

OBJECTIVES

To elucidate a novel anti-inflammatory mechanism of myrrh against lipopolysaccharide (LPS)-induced inflammation.

METHODS

RAW264.7 macrophages were cultured in DMEM and then cells were treated with LPS or LPS plus a myrrh methanol extract (MME) for 24h. The culture medium was collected for determination of nitric oxide (NO), prostaglandin (PG)E(2) , interleukin (IL)-1β, and tumour necrosis factor (TNF)-α, and cells were harvested by lysis buffer for Western blot analysis.

KEY FINDINGS

Our data showed that treatment with the MME (1∼100µg/ml) did not cause cytotoxicity or activate haem oxygenase-1 (HO-1) protein synthesis in RAW264.7 macrophages. Furthermore, the MME inhibited LPS-stimulated NO, PGE(2) , IL-1β and TNF-α release and inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 protein expression. Zn(II) protoporphyrin IX, a specific inhibitor of HO-1, blocked the inhibition of iNOS and COX-2 expression by the MME.

CONCLUSIONS

These results suggest that among mechanisms of the anti-inflammatory response, the MME inhibited the production of NO, PGE(2) , IL-1β and TNF-α by downregulating iNOS and COX-2 gene expression in macrophages and worked through the action of HO-1.

Extract of the dried heartwood of Caesalpinia sappan L. attenuates collagen-induced arthritis

AIM OF THIS STUDY

To confirm the anti-arthritic effect and explore the potential mechanism of the dried heartwood of Caesalpinia sappan L. (HCS) on collagen-induced arthritis (CIA) in rats, an animal model of rheumatoid arthritis.

MATERIALS AND METHODS

CIA was induced in male Wistar rats by intradermal injection of bovine collagen-II in Freund's incomplete adjuvant (IFA). The rats in the onset of arthritis were treated daily with oral administration of an ethanol extract from HCS (EHCS) at different doses (1.2, 2.4 and 3.6g/kg) or olive oil-vehicle for 10 days. Paw swelling, arthritis index, radiographic and histopathologic changes were evaluated to confirm the anti-arthritic effect of EHCS on CIA in rats. Levels of proinflammatory cytokines interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) as well as prostaglandin E2 (PGE2) in blood and expression of cyclooxygenase-2 (COX-2) and transcription factor NF-κB p65 in paw cartilage were detected to further study the molecular mechanism of the anti-arthritic effects of EHCS on CIA in rats. In addition, the adverse effects of EHCS on liver and kidney of rats were also evaluated.

RESULTS

The results showed that the EHCS markedly attenuated collagen-induced arthritis and reduced the levels of IL-1β, IL-6, TNF-α and PGE2 in serum and the expression of COX-2 and transcription factor NF-κB p65 in paw cartilage of CIA rats. EHCS (3.6g/kg) induced slight hepatotoxicity and body weight loss.

CONCLUSION

These results indicate that EHCS significantly attenuates CIA in rats by decreasing the levels of IL-1β, IL-6, TNF-α and PGE2 in serum and the expression of COX-2 and transcription factor NF-κB in paw cartilage.

Protective effect of dried safflower petal aqueous extract and its main constituent, carthamus yellow, against lipopolysaccharide-induced inflammation in RAW264.7 macrophages

BACKGROUND

Safflower, whose botanic name is Carthamus tinctorius L., is a member of the family Compositae or Asteraceae. Carthamus yellow (CY) is the main constituent of safflower and is composed of safflomin A and safflomin B. Dried safflower petals are used in folk medicine and have been shown to invigorate blood circulation, break up blood stasis, and promote menstruation. In addition, dried safflower petals contain yellow dyes that are used to color food and cosmetics. In this study, we investigated the effects of dried safflower petals aqueous extracts (SFA) and CY on lipopolysaccharide (LPS)-induced inflammation using RAW264.7 macrophages.

RESULTS

Our data showed that treatment with SFA (1-1000 microg mL(-1)) and CY (1-2000 microg mL(-1)) does not cause cytotoxicity in cells. SFA and CY inhibited LPS-stimulated nitric oxide (NO), prostaglandin E(2) (PGE(2)), and interleukin 1β (IL-1β) release, through attenuation of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression. Further, SFA and CY suppressed the LPS-induced phosphorylation of nuclear factor-κB, which was associated with the inhibition of IκB-α degradation.

CONCLUSION

These results suggest that SFA and CY provide an anti-inflammatory response through inhibiting the production of NO and PGE(2) by the downregulation of iNOS and COX-2 gene expression. Thus safflower petals have the potential to provide a therapeutic approach to inflammation-associated disorders.

Dilinoleoylphosphatidylcholine induces the expression of the anti-inflammatory heme oxygenase-1 in RAW264.7 macrophages

1,2-Dilinoleoyl-sn-glycero-3-phosphocholine (DLPC), the main and active component of soybean lecithin, has been reported to exert anti-inflammatory effects, but the underlying mechanisms remain to be established. It was found that DLPC could induce the expression of the anti-inflammatory heme oxygenase-1 (HO-1) through the activation of nuclear erythroid 2-related factor 2 (Nrf2) in RAW264.7 macrophages. Pretreatment with DLPC suppressed the expression of inducible nitric oxide (NO) synthase (iNOS), one of proinflammatory enzymes, and reduced NO production in lipopolysaccharide (LPS)-stimulated macrophages. Similarly, DLPC also diminished the production of tumor necrosis factor-alpha (TNF-alpha), one of proinflammatory cytokines. Interestingly, the inhibitory effects of DLPC on LPS-induced iNOS expression and TNF-alpha production were reversed by tin protoporphyrin, a HO-1 inhibitor. Thus, HO-1 expression via Nrf2 activation may be one of the possible mechanisms explaining the anti-inflammatory effects of DLPC.

Anti-inflammatory effects of apigenin on nicotine- and lipopolysaccharide-stimulated human periodontal ligament cells via heme oxygenase-1

BACKGROUND AND OBJECTIVES

Although apigenin exhibits various biological effects, its anti-inflammatory role in the periodontal field remains unknown. We examined the anti-inflammatory effects of apigenin and the underlying mechanism in nicotine- and lipopolysaccharide (LPS)-stimulated human periodontal ligament (hPDL) cells.

MATERIALS AND METHODS

Western blotting was used to examine the effect of apigenin (10-40 microM) on the LPS- and nicotine-induced expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and heme oxygenase-1 (HO-1), as well as the phosphorylation of mitogen-activated protein kinases (MAPKs), in hPDL cells. Pro-inflammatory mediators, including nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), IL-6, and IL-12 were monitored using Griess reagents and ELISA.

RESULTS

Incubation of hPDL cells with apigenin decreased LPS- and nicotine-induced HO-1 protein expression and activity. Apigenin significantly inhibited the nicotine- and LPS-induced production of NO, PGE2, IL-1beta, TNF-alpha, IL-6, and IL-12, and the upregulation of iNOS and COX-2 in hPDL cells. Hemin, a selective HO-1 inducer, reversed the apigenin-mediated suppression of nicotine- and LPS-induced NO, PGE2 and cytokine production. Treatment with inhibitors of the phosphoinositide 3-kinase, MAPKs, p38, and JNK, as well as a protein kinase C inhibitor, blocked the anti-inflammatory effects of apigenin in nicotine- and LPS-treated cells.

CONCLUSIONS

Apigenin possesses anti-inflammatory activity in hPDL cells and works through a novel mechanism involving the action of HO-1. Thus, apigenin may have potential benefits as a host modulatory agent in the prevention and treatment of periodontal disease associated with smoking and dental plaque.