Brazilin isolated from Caesalpinia sappan L. inhibits rheumatoid arthritis activity in a type-II collagen induced arthritis mouse model

Traditional Uses and Phytochemical and Pharmacological Analyses of Caesalpinia sappan Linn

The heartwood of Caesalpinia sappan Linn. (Sappan Lignum) has been traditionally utilized as an herbal drug in China for treating several diseases, including osteoporosis and wounds. This review presents a systematic summary of botanical, pharmacological, phytochemical, and pharmacokinetic characteristics; traditional applications; and safety profile of C. sappan to highlight requirements for conducting further studies on this plant and to report its potential uses. We conducted a literature search of relevant articles on C. sappan published in several databases. Additional information was collected from peer-reviewed academic journals, doctoral dissertations, master's theses, and Chinese herbal medicine books. We confirmed plant taxonomy by searching The Plant List database (http://www.theplantlist.org). According to traditional Chinese medicine (TCM) literature, Sappan Lignum promotes blood circulation by eliminating blood stasis, induces detumescence, and provides pain relief. A total of 127 active components were identified and isolated from C. sappan; these include terpenoids, flavonoids, quinones, phenols, steroids, and alkaloids, showing protective effects against inflammation and carcinogenesis of cardio-cerebrovascular, hepatic, and renal systems. According to recent pharmacological studies, C. sappan has several pharmacological applications for treating cancer, inflammation, and cardio-cerebrovascular diseases. Most activities of C. sappan could be attributed to flavonoids; however, there is limited information regarding the underlying molecular mechanisms, metabolic activities, structure-function relationships, and toxicology of the bioactive substances of C. sappan. Additional extensive investigations are required to analyze the medicinal properties of C. sappan.

Unlocking the therapeutic mechanism of Caesalpinia sappan: a comprehensive review of its antioxidant and anti-cancer properties, ethnopharmacology, and phytochemistry

Herbal medicine are an invaluable reservoir of bioactive compounds, offering immense potential for novel drug development to address a wide range of diseases. Among these, Caesalpinia sappan has gained recognition for its historical medicinal applications and substantial therapeutic potential. This review explores the ethnopharmacological significance, phytochemical composition, and pharmacological properties of C. sappan, with a particular focus on its anticancer activities. Traditionally, C. sappan has been utilized for treating respiratory, gastrointestinal, and inflammatory conditions, demonstrating its broad therapeutic scope. The plant's rich array of bioactive compounds-flavonoids, triterpenoids, phenolic acids, and glycosides-forms the basis of its potent antioxidant, anti-inflammatory, and pharmacological effects. Modern pharmacological research has further substantiated its versatility, revealing anticancer, anti-diabetic, anti-infective, and hepatoprotective properties. However, significant challenges remain, including the need to unravel the precise molecular mechanisms underlying its anticancer effects, refine extraction and isolation methods for bioactive compounds, and validate its safety and efficacy through well-designed clinical trials. Particularly noteworthy is C. sappan's potential in combination therapies, where it may synergistically target multiple cancer pathways, enhance therapeutic outcomes, and mitigate adverse effects. This review synthesizes the findings from the past decade, providing a comprehensive evaluation of C. sappan's pharmacological promise while identifying critical areas for future research. By addressing these gaps, C. sappan could serve as a cornerstone for innovative therapeutic strategies, offering hope for improved management of cancer and other complex diseases.

Iron chelating, antioxidant, and anti-inflammatory properties of brazilin from Caesalpinia sappan Linn

Background

Iron overload and inflammation are severe conditions that can lead to various chronic diseases. However, the current iron chelator drugs have their limitations. The phytochemical compounds from herbals, such as brazilin, the major active compound in Caesalpinia sappan Linn., have significant therapeutic potential in various chronic diseases. Our study was designed to examine the effect of brazilin on iron chelating properties, antioxidant activity in hepatocytes, and anti-inflammatory potential in macrophages.

Methods

This study focused on the isolation, purification, and evaluation of brazilin, the principal bioactive constituent found in C. sappan wood. Brazilin was extracted via methanol maceration followed by column chromatography purification. The purified compound was characterized using high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry (MS). The antioxidant potential of brazilin was assessed by in vitro assays, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzthiazolin-6-sulfonic acid (ABTS), and ferric-reducing antioxidant power (FRAP). Furthermore, its cellular antioxidant activity was evaluated using hydrogen peroxide-induced oxidative stress in the hepatocellular carcinoma cell line (Huh-7). The iron-chelating capacity of brazilin was determined spectrophotometrically, and Job's plot method was used to elucidated the stoichiometry of the iron-brazilin complex formation. The anti-inflammatory properties of brazilin were investigated in lipopolysaccharide (LPS)-stimulated macrophages (RAW 264.7). Nitric oxide (NO) inhibition was quantified using the Griess reagent, while the expression levels of pro-inflammatory cytokines, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), were evaluated by RT-qPCR.

Results

The results demonstrated that brazilin exhibited potent antioxidant activity in vitro and hepatocytes in a concentration-dependent manner. It also showed anti-inflammatory activity, in which NO production was significantly reduced and IL-6 and TNF-α expression in LPS-induced macrophages were repressed. Furthermore, it can bind ferric and ferrous ions. Brazilin acts as a bidentate iron chelator that forms a complex with iron in a 2:1 ratio, and two water molecules are used as additional chelators in this complex.

Conclusions

Our findings have significant implications. Brazilin can potentially alleviate the harmful effects of iron-induced oxidative stress and inflammatory disorders.

Mechanisms of action of Sappan lignum for prostate cancer treatment: network pharmacology, molecular docking and experimental validation

BACKGROUND

Prostate cancer (PCa) is the most common non-cutaneous malignancy in men globally. Sappan lignum, which exists in the heartwood of Caesalpinia sappan L., has antitumor effects; however, its exact mechanism of action remains unclear. This study elucidated the underlying mechanisms of Sappan lignum in PCa through network pharmacology approaches and molecular docking techniques. Moreover, the therapeutic effects of Sappan lignum on PCa were verified through in vitro experiments.

METHODS

The constituent ingredients of Sappan lignum were retrieved from the HERB database. Active plant-derived compounds of Sappan lignum were screened based on gastrointestinal absorption and gastric drug properties. Disease targets for PCa were screened using unpaired and paired case datasets from the Gene Expression Omnibus. Intersection targets were used for gene ontology and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Core targets were identified through topological analysis parameters and their clinical relevance was validated through The Cancer Genome Atlas database. The affinity between the phytochemicals of Sappan lignum and core proteins was verified using the molecular docking technique. Validation experiments confirmed the significant potential of Sappan lignum in treating PCa.

RESULTS

Twenty-one plant-derived compounds of Sappan lignum and 821 differentially expressed genes associated with PCa were collected. Among 32 intersection targets, 8 were screened according to topological parameters. KEGG analysis indicated that the antitumor effects of Sappan lignum on PCa were primarily associated with the p53 pathway. The molecular docking technique demonstrated a strong affinity between 3-deoxysappanchalcone (3-DSC) and core proteins, particularly cyclin B1 (CCNB1). CCNB1 expression correlated with clinicopathological features in patients with PCa. Experimental results revealed that 3-DSC exhibited anti-proliferative, anti-migratory, and pro-apoptotic effects on 22RV1 and DU145 cells while also causing G2/M phase cell cycle arrest, potentially through modulating the p53/p21/CDC2/CCNB1 pathway.

CONCLUSION

This research highlights the promising therapeutic potential of Sappan lignum in treating PCa, with a particular focus on targeting the p53 pathway.

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.

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 of Shengdeng in Tibetan medicine: textual research, herbal and botanical distribution, traditional uses, phytochemistry, and pharmacology

"Shengdeng", a group of Tibetan medicines with diverse biological origins, has long been utilized in Tibet for the treatment of rheumatoid arthritis. It showcases remarkable efficacy in alleviating rheumatism, reducing swelling, and relieving pain. This study aimed to clarify the plant species used as "Shengdeng" and summarize their botanical distribution, traditional uses, phytochemistry, and pharmacology to promote its utilization and development. "Shengdeng" is derived from a remarkable collection of 14 plant species belonging to six distinct families. Extensive phytochemical investigations have led to the identification of 355 chemical constituents within "Shengdeng". Pharmacological studies conducted on "Shengdeng" have revealed a wide range of beneficial properties, including antioxidant, anticancer, antimicrobial, antiviral, antiparasitic, anti-inflammatory, and anti-arthritic activities. Notably, flavonoids and triterpenoids emerge as the predominant groups among these constituents, contributing to the therapeutic potential and diverse applications of "Shengdeng". The present review provides a concise summary of the recent advancements in textual research concerning the herbal and botanical distribution, traditional uses, phytochemistry, and pharmacological activities of "Shengdeng". It is crucial to note that future research on "Shengdeng" should prioritize the analysis of its active ingredients and the establishment of rigorous quality standards. These aspects are essential for ensuring consistency, efficacy, and safety in its clinical application.

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.

Brazilin from Caesalpinia sappan inhibits viral infection against PRRSV via CD163ΔSRCR5 MARC-145 cells: an in silico and in vitro studies

This research aimed to identify bioactive compounds from Caesalpinia sappan extract that function as novel porcine reproductive and respiratory syndrome virus (PRRSV) infection inhibitors by computational molecular screening. We obtained a set of small-molecule compounds predicted to target the scavenger receptor cysteine-rich domain 5 (SRCR5) of CD163. In addition, the functions of positive hits were assessed and verified utilizing an in vitro antiviral activity assay with PRRSV-infected MARC-145 cells. Combining molecular docking with the results of binding affinity and ligand conformation, it was found that brazilin had the highest binding energy with the SRCR5 receptor compared to catechin and epicatechin (- 5.8, - 5.5, and - 5.1 kcal/mol, respectively). In terms of molecular mechanics, the binding free energy between the SRCR5 receptor was - 15.71 kcal/mol based on the Poisson-Boltzmann surface area of brazilin. In addition, PRRSV infection in MARC-145 cells was significantly inhibited by brazilin compared to the control (virus titer, 4.10 vs. 9.25 TCID₅₀/mL, respectively). Moreover, brazilin successfully limited the number of PRRSV RNA copies in MARC-145 cells as determined by RT-qPCR. By inhibiting the PRRSV-CD163 interaction with brazilin from Caesalpinia sappan, it may be possible to prevent PRRSV infection in pigs, as suggested by this research.

Caesalpinia sappan Linn. Ameliorates Allergic Nasal Inflammation by Upregulating the Keap1/Nrf2/HO-1 Pathway in an Allergic Rhinitis Mouse Model and Nasal Epithelial Cells

Allergic rhinitis (AR) is a common upper-airway inflammatory disease of the nasal mucosa caused by immunoglobulin (IgE)-mediated inflammation. AR causes various painful clinical symptoms of the nasal mucosa that worsen the quality of daily life, necessitating the urgent development of therapeutic agents. Herein, we investigated the effects of Caesalpinia sappan Linn. heartwood water extract (CSLW), which has anti-inflammatory and antioxidant properties, on AR-related inflammatory responses. We examined the anti-inflammatory and anti-allergic effects of CSLW in ovalbumin (OVA)-induced AR mice and in primary human nasal epithelial cells (HNEpCs). Administration of CSLW mitigated allergic nasal symptoms in AR mice, decreased total immune cell and eosinophil counts in nasal lavage fluid, and significantly reduced serum levels of OVA-specific IgE, histamine, and Th2 inflammation-related cytokines. CSLW also inhibited the infiltration of several inflammatory and goblet cells, thereby ameliorating OVA-induced thickening of the nasal mucosa tissue. We found that CSLW treatment significantly reduced infiltration of eosinophils and production of periostin, MUC5AC, and intracellular reactive oxygen species through the Keap1/Nrf2/HO-1 pathway in HNEpCs. Thus, our findings strongly indicate that CSLW is a potent therapeutic agent for AR and can improve the daily life of patients by controlling the allergic inflammatory reaction of the nasal epithelium.

Identification of Protosappanoside D from Caesalpinia decapetala and Evaluation of Its Pharmacokinetic, Metabolism and Pharmacological Activity

Protosappanoside D (PTD) is a new component isolated from the extract of Caesalpinia decapetala for the first time. Its structure was identified as protosappanin B-3-O-β-D-glucoside by ¹H-NMR, ¹³C-NMR, 2D-NMR and MS techniques. To date, the pharmacological activities, metabolism or pharmacokinetics of PTD has not been reported. Therefore, this research to study the anti-inflammatory activity of PTD was investigated via the LPS-induced RAW264.7 cells model. At the same time, we also used the UHPLC/Q Exactive Plus MS and UPLC-MS/MS methods to study the metabolites and pharmacokinetics of PTD, to calculate its bioavailability for the first time. The results showed that PTD could downregulate secretion of the pro-inflammatory cytokines. In the metabolic study, four metabolites were identified, and the primary degradative pathways in vivo involved the desaturation, oxidation, methylation, alkylation, dehydration, degradation and desugarization. In the pharmacokinetic study, PTD and its main metabolite protosappanin B (PTB) were measured after oral and intravenous administration. After oral administration of PTD, its T_max was 0.49 h, t_1/2z and MRT_(0–t) were 3.47 ± 0.78 h and 3.06 ± 0.63 h, respectively. It shows that PTD was quickly absorbed into plasma and it may be eliminated quickly in the body, and its bioavailability is about 0.65%.

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.

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.

Caesalpinia sappan: A promising natural source of antimicrobial agent for inhibition of cariogenic bacteria

From the previous findings, the ethanolic fractionated extract of Caesalpinia sappan (F-EtOH) has high activity against Streptococcus mutans, the most severe cariogenic bacteria. The present study was aimed to isolate and identify the active compound of F-EtOH and compare its inhibitory activity against the biofilm of S. mutans as well as the cytotoxicity to oral fibroblast cells with F-EtOH. Compound isolation was done by column chromatography. The active compound was identified using liquid chromatography-mass spectrometry with electrospray ionization and nuclear magnetic resonance spectroscopy. It was found that the major compound of F-EtOH is brazilin. F-EtOH and brazilin were compared for inhibitory potential on the biofilms of three strains of S. mutans. The results exhibited that both F-EtOH and brazilin had potential on inhibiting biofilm formation and eradicating the preformed biofilms and their activity was dose dependent. F-EtOH showed significantly less toxic to normal periodontal ligament fibroblast than brazilin. At low concentration of 1- and 2-MBC, F-EtOH showed higher effective than brazilin. The results of our study suggest that the antibacterial activity of F-EtOH is according to the synergistic effects of the existing compounds including brazilin in F-EtOH.

Optimization of Caesalpinia sappan L. heartwood extraction procedure to obtain the highest content of brazilin and greatest antibacterial activity

OBJECTIVE

The objective of the work was to optimize the extraction conditions of Caesalpinia sappan L. heartwood in order to maximize the brazilin content and antibacterial activity of the extract.

METHODS

Two independent factors were studied: extraction temperature (45-95 °C) and extraction time (30-60 min). In addition, five dependent factors were monitored, including extraction yield, brazilin content, and clear zones against Staphylococcus aureus TISTR 1466, Staphylococcus epidermidis TISTR 518 and Propionibacterium acnes DMST 14961. The brazilin content was quantified by high-performance liquid chromatography and antibacterial activity was determined by disk diffusion assay.

RESULTS

The high temperature provided high total extract yield as well as brazilin content, while extraction time had little effect on yield or brazilin content. Extraction time had a positive effect, while extraction temperature had little effect on clear zone against S. aureus. The largest clear zone against S. epidermidis was achieved at low extraction temperature and long extraction time. Conversely, short extraction time and high extraction temperature provided the largest clear zone against P. acnes. The optimal conditions providing the highest brazilin content was an extraction temperature and extraction time of 95 °C and 30 min, respectively. The same optimal conditions also provided the simultaneous greatest antibacterial activity against the three bacteria. Modeled optimal conditions were validated be conducting extraction using these values. Yield and antibacterial activity of the resulting extract demonstrated that the model had a low percentage error.

CONCLUSION

The optimal condition will be used as a standard condition for extraction of C. sappan heartwood to maximize brazilin content and antibacterial activity.

Stereoselective Convergent Synthesis of Tetrahydro-5 H-benzo[ c]fluorene via Nine-Membered Ring-Closing Metathesis and Transannular Acid-Mediated Cyclization/Nucleophilic Addition

The diene methyl ethers or acetates, constructed from the Li-Br exchange/addition reactions of 2-vinylbenzaldehydes and 2-(but-3-en-1-yl)bromoarenes followed by etherification or acetylation of the corresponding alcohols, smoothly underwent the ring-closing metathesis (RCM) by using Hoveyda-Grubbs II as a catalyst to provide the corresponding benzannulated ( Z)-cyclononenes as single products in good yields (up to 75%). The ensuing one-pot acid-mediated transannular cyclization/nucleophilic addition at C7 furnished the corresponding tetrahydro-5 H-benzo[ c]fluorenes as single stereoisomers with the exclusive cis stereochemistry at the ring junction (C5-C6) and trans at the site of nucleophilic attack (C6-C7) on the three contiguous stereogenic centers in good to excellent yield (up to 94%). The developed strategy was general; the reaction conditions were compatible with hydride, azide, and electron-rich aromatics as nucleophiles. In addition, various methoxylated benzannulated cyclononene acetates could be employed as substrates. Thus, tetrahydro-5 H-benzo[ c]fluorenes could be prepared in four steps from appropriately substituted bromoarenes and benzaldehydes in good yields (up to 56%) with excellent stereo- and regio-control.

The Ethanolic Extract of Caesalpinia sappan Heartwood Inhibits Cerebral Ischemia/Reperfusion Injury in a Rat Model Through a Multi-Targeted Pharmacological Mechanism

Background: Caesalpinia sappan L. (C. sappan) is a traditional Chinese medicinal plant. The dried heartwood of C. sappan (also known as Sappan wood) has been widely used for the folkloric medical treatment of ischemic cerebral stroke in China. However, the detailed underlying pharmacological mechanism still remains largely unexplored. Methods: In this study, a middle cerebral artery occlusion (MCAO) rat model was employed to elucidate the mechanism of the anti-cerebral ischemic effects of C. sappan ethanolic extract (CEE). Moreover, systemic multi-target identification coupled with gene ontology biological process (GO BP) and reactome pathway analysis was used to investigate the potential neuroprotective mechanism. Furthermore, the presumed mechanism was confirmed through biological analysis by determining the effects of CEE on the identified signaling pathways in PC12 cells model-induced by oxygen-glucose deprivation/reperfusion (OGD/R). Results: Our study demonstrates that CEE (both through in vivo administration at a dosage of 300 mg/kg and through in vitro incubation at a dosage of 2.4 μg/mL) is a neuroprotective agent that can effectively inhibit neuronal damage, promote synaptic generation, and suppress the activation of neutrophils, microglia, and astrocytes. Moreover, the neuroprotective mechanism of CEE is mediated via regulating 150 potential target proteins, which are associated with 6 biological processes and 10 pathways, including JAK-STAT, HSP90 and DNA damage/telomere stress. Conclusion: CEE can exert neuroprotective effect through multi-target pharmacological mechanisms to prevent ischemia/reperfusion-induced cerebral injury.

Early supplemental α2-macroglobulin attenuates cartilage and bone damage by inhibiting inflammation in collagen II-induced arthritis model

OBJECTIVE

To determine if early supplemental intra-articular α2-macroglobulin (A2M) has a chondroprotective effect in a collagen II-induced arthritis (CIA) mice model.

METHODS

DBA/1 mice were randomized into four groups (n = 15/group): (a) CIA + 1.2 μg of A2M; (b) CIA + 0.8 μg of A2M; (c) CIA + 0.4 μg of A2M; (d) vehicle + phosphate-buffered saline (PBS). A2M was injected into right ankles and PBS was injected into the left ankles simultaneously as internal control at days 36, 43 and 50. The CIA inflammation clinical score and ankle thickness were recorded every other day starting on day 21 until sacrifice. Changes in inflammation were monitored by in vivo fluorescence molecular tomography (FMT). Inflammation, cartilage and bone damage were assessed with X-ray, histology and immunohistochemistry. Cartilage and inflammation-related gene expression was quantified by real-time polymerase chain reaction (PCR).

RESULTS

All mice showed ankle inflammation on day 33. After day 43, lower clinical scores, ankle thickness and Sharp/van der Heijde method scores in A2M-treated ankles compared with PBS-treated ankles. FMT data indicated that the inflammation markers MMPSense and ProSense were significantly elevated in the PBS-treated ankles than A2M-treated ankles. Histology and X-ray analyses indicated that A2M administration resulted in lower levels of inflammatory infiltration and synovial hyperplasia, as well as more typical cartilage and bone organization with increased COL II and Aggrecan staining when compared with PBS-treated ankles. In addition, real-time PCR showed that,matrix metalloproteinase-3, -9, -13, COL X and Runx2 were significantly less expressed in A2M-treated groups than PBS-treated animals.

CONCLUSION

Early supplemental intra-articular A2M exerts an anti-inflammatory effect and attenuates cartilage and bone damage in a CIA model.

Brazilin blocks catabolic processes in human osteoarthritic chondrocytes via inhibition of NFKB1/p50

This study aimed to evaluate the chondroprotective and anti-inflammatory activity of brazilin in human osteoarthritic (OA) cartilage and chondrocytes with particular focus on the nuclear factor-kappa B (NF-κB) pathway. Therefore, brazilin was isolated from Caesalpinia sappan and identified using high performance liquid chromatography (HPLC). The effect of brazilin was assessed in cartilage explants treated with 10 ng/ml interleukin (IL)-1β and 10 ng/ml tumor necrosis factor (TNF)-α using histological and biochemical glycosaminoglycan (GAG) analyses and in primary chondrocytes treated with 10 ng/ml IL-1β using RT-qPCR, ELISA, and Western blot. The involvement of NF-κB signaling was examined using a human NF-κB signaling array and in silico pathway analysis. Brazilin was found to reduce the GAG loss from cartilage explants stimulated with IL-1β and TNF-α. NF-κB pathway analysis in chondrocytes revealed NFKB1/p50 as a central player regulating the anti-inflammatory activities of brazilin. Brazilin suppressed the IL-1β-mediated up-regulation of OA markers and the induction of NFKB1/p50 in chondrocytes. In conclusion, brazilin effectively attenuates catabolic processes in human OA cartilage and chondrocytes-at least in part due to the inhibition of NFKB1/p50-which indicates a chondroprotective potential of brazilin in OA. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2431-2438, 2018.

Chronic Calcium Channel Inhibitor Verapamil Antagonizes TNF-α-Mediated Inflammatory Reaction and Protects Against Inflammatory Arthritis in Mice

It is well established that the tumor necrosis factor-α (TNF-α) plays a dominant role in rheumatoid arthritis (RA). Calcium channel is recently reported to be closely associated with various inflammatory diseases. However, whether chronic calcium channel blocker verapamil plays a role in RA still remains unknown. To investigate the role of verapamil in antagonizing TNF-α-mediated inflammation reaction and the underlying mechanisms, bone marrow-derived macrophages (BMDM) cells were cultured with stimulation of TNF-α, in the presence or absence of verapamil. Inflammation-associated cytokines, including IL-1, IL-6, inducible nitric oxide synthase 2 (NOS-2), and cyclooxygenase-2 (COX-2), were assessed, and verapamil suppressed TNF-α-induced expression of inflammatory cytokines. Furthermore, collagen-induced arthritis (CIA) mice models were established, and arthritis progression was evaluated by clinical and histological signs of arthritis. Treatment of verapamil attenuated inflammation as well as joint destruction in arthritis models. In addition, activity of NF-kB signaling pathway was determined both in vitro and in mice arthritis models, and verapamil inhibited TNF-α-induced activation of NF-kB signaling both in vitro and in mice models. Collectively, chronic calcium channel blocker verapamil may shed light on treatment of inflammatory arthritis and provide a potential therapeutic instrument for RA in the future.

Kinsenoside inhibits the inflammatory mediator release in a type-II collagen induced arthritis mouse model by regulating the T cells responses

Background

Anoectochilus formosanus has been used as a Chinese folk medicine and is known as the “King of medicine” in Chinese society due to its versatile pharmacological effects such as anti-hypertension, anti-diabetes, anti-heart disease, anti-lung and liver diseases, anti-nephritis and anti-Rheumatoid arthritis. Kinsenoside is an essential and active compound of A. formosanus (Orchidaceae). However, the anti-arthritic activity of kinsenoside has still not been demonstrated. In the present study, we confirmed that the kinsenoside treatment rheumatoid arthritis induced by collagen-induced arthritis in mice.

Methods

Male DBA/1 J mice were immunized by intradermal injection of 100 μg of type II collagen in CFA. Kinsenoside was administered orally at a dose of 100 and 300 mg/kg once a day after 2nd booster injection. Paw swelling, arthritic score and histological change were measured. ELISA was used to measure cytokines including tumor necrosis factor alpha (TNF-α), interleukin-10 (IL-10), interleukin-17 (IL-17) and interferon-γ (IFN-γ) in the splenocyte according to the manufacturer’s instructions.

Results

Compared with model group, kinsenoside significantly inhibited paw edema and decreased the arthritis score and disease incidence. Histopathological examination demonstrated that kinsenoside effectively protected bone and cartilage of knee joint from erosion, lesion and deformation versus those from the CIA group. Kinsenoside also decreased IL-1β, TNF-α, and MMP-9 expression, and increased the expression of IL-10 in inflamed joints. The administration of kinsenoside significantly suppressed levels of TNF-α, IFN-γ, and IL-17, but increased concentrations of IL-10 in the supernatants of each of the splenocytes in CIA mice compared with that in the H₂O-treated mice with CIA. Using flow cytometric analysis, we demonstrated that kinsenoside increases the population of CD4⁺CD25⁺ regulatory T cells, thereby inhibiting the Th1 cell and B cell populations. Anticollagen IgG1 and IgG2a levels decreased in the serum of kinsenoside-treated mice.

Conclusions

These results suggest that the administration of kinsenoside effectively suppressed inflammatory mediators’ production and bone erosion in mice with collagen-induced arthritis showing the potential as an anti-arthritis agent.

Brazilin Limits Inflammatory Responses through Induction of Prosurvival Autophagy in Rheumatoid Fibroblast-Like Synoviocytes

Brazilin is an active compound of Caesalpinia sappan L. (Leguminosae), which possesses pro-apoptotic and anti-inflammation potentials depending on the specific cell type. However, it is largely unknown whether autophagy is implicated in the mechanism underlying its chemotherapeutic and anti-inflammatory effects in rheumatoid arthritis (RA). Here, we show that treatment of RA fibroblast-like synoviocytes (FLS) with brazilin results in enhanced level of autophagic flux, evidenced by accumulation of autophagosome and increased level of lipidated LC3 (LC3-II), which is mainly mediated by enhanced production of reactive oxygen species (ROS). Interestingly, long-term exposure of brazilin was able to restore cell survival against the cytotoxity, exclusively in RA FLS, but not in normal fibroblast. Importantly, such a restoration from brazilin-induced cytotoxity in RA FLS was completely abrogated after co-treatment with autophagy inhibitors including NH4Cl or chloroquine. Furthermore, we found that the pretreatment of RA FLS with brazilin reduced LPS- or TNF-induced NF-κB activation and the secretion of inflammatory cytokines in parallel with the enhanced autophagic flux. Such anti-NF-κB potentials of brazilin were drastically masked in RA FLS when autophagy was suppressed. These results suggest that brazilin is capable of activating autophagy exclusively in RA FLS, and such inducible autophagy promotes cell survival and limits inflammatory response.