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This body of work revolves around two themes: palladium-catalyzed construction of new carbon–nitrogen (C–N) bonds in an enantioselective fashion, and the total synthesis of naturally occurring indano[2,1-c] chromans of biological interest. The development of new methods to synthesize complex molecules in an efficient and stereocontrolled manner is an essential goal. Transition metal catalysis has broadened the types of disconnections and connections available to synthetic chemists. Palladium carbene intermediates provide a new point of disconnection that has gained popularity. Not only do palladium carbene intermediates generate new carbon–carbon and carbon–heteroatom bonds, but they do so while providing an avenue for chiral control. Many biologically active compounds, such as RYDAPT®, contain aromatic heterocycles attached to chiral centers through a C–N bond. Methods to generate these types of linkages from achiral fragments with control of stereochemistry are invaluable. This work describes a method to access chiral C–N bonds between achiral α-aryl-α-diazocarbonyl compounds and achiral aromatic heterocycles containing N–H bonds. Naturally occurring indano[2,1-c]chromans, such as (±)-brazilin, (±)-pestalachloride C, and (±)-pestalachloride D, are of analytical or biological importance. The second part of this work describes the synthesis of these three biologically active indano[2,1-c]chromans. (±)-Brazilin, a highly oxygen sensitive species, has been studied for its pharmacological activity since the discovery of its structural framework. Prior syntheses of (±)-brazilin that have utilized a common strategy: an intramolecular Friedel-Crafts-type acylation of an aromatic ring. The total synthesis described in this work takes advantage of palladium-catalyzed carbene insertion reaction to provide the core structure of (±)-brazilin through a non-obvious bond-disconnection. The carbene insertion approach was less efficient when applied to the synthesis of the highly functionalized indano[2,1-c]chroman core of (±)-pestalachloride C and (±)-pestalachloride D which occur in nature as racemates. These compounds exhibit interesting biological activity because pestalachloride C exhibits teratogenic activity whereas pestalachloride D does not. A biomimetic synthesis of these two compounds was developed which seems to support the Knoevenagel/hetero-Diels–Alder cascade reaction proposed for the biosynthesis. This concise synthesis facilitates construction of chemical analogues with higher potency.

Kayu Secang (Caesalpinia sappan L.) dimanfaatkan sebagai antioksidan pada produk kosmetik. Beberapa kandungan senyawa di dalamnya adalah brazilin, brazilein, 3´-O-metilbrazilin, sappanon, kalkon, dan sappankalkon sebagai metabolit sekunder yang berpotensi sebagai antioksidan. Penelitian ini bertujuan untuk memformulasi hair tonic dari ekstrak dan fraksi kayu secang, menentukan kualitas, dan aktivitas pertumbuhan rambut formula hair tonic menggunakan ekstrak etanol (Eet), fraksi etanol (Fen), dan fraksi kloroform-metanol (Fkm) kayu secang. Simplisia kayu secang dimaserasi menggunakan etanol 96 %, kemudian dipartisi menggunakan n-heksana. Fraksi etanol selanjutnya diaplikasikan menggunakan kromatografi kolom vakum (KKV) menggunakan eluen kloroform, kloroform:metanol (5:1), dan kloroform. Eet, Fen, dan Fkm kayu secang kemudian diformulasi ke dalam sediaan hair tonic. Evaluasi hair tonic meliputi pengujian organoleptis, penentuan pH, penentuan viskositas, pengujian homogenitas, dan pengujian aktivitas pertumbuhan rambut. Hasil penelitian menunjukkan bahwa ketiga formula hair tonic menghasilkan warna merah-jingga, berbau aromatik dengan bentuk cair/larutan, memiliki pH 7, homogen, dan viskositas 3 cps. Ketiga formula hair tonic memberikan aktivitas pertumbuhan rambut kelinci pada parameter panjang rambut dan bobot rambut. FIII yang mengandung fraksi kloroform-metanol kayu secang memberikan hasil berbeda bermakna dengan kontrol negatif pada data panjang rambut kelinci hari ke 30 yang menunjukkan bahwa FIII memberikan aktivitas terbaik. Ketiga formula memenuhi persyaratan mutu hair tonic dan memberikan aktivitas pertumbuhan rambut.

Brazilin, a constituent of the Chinese medicine heartwood, exhibits pronounced anti-tumor effects. To date, brazilin quantification mostly relies on high-performance liquid chromatography (HPLC), which is not accurate enough because of an easily oxidizable structure. Herein, a thin-layer chromatography (TLC)-based method was developed for the quantitative analysis of brazilin. A water solution of purified brazilin was spotted on a GF254 silica gel plate and developed using a mixture of chloroform‒acetone‒formic acid (8:4:1, V/V). After ammonia vaporing, AlCl3 solution (90 mg/mL) was sprayed to form a stable compound. Detection was performed at 508 nm using a dual-beam TLC scanner, and brazilin was quantitatively analyzed by using an external standard. The optimal time for ammonia vaporing was 6 min. Sample stability remained for 10‒200 min. At 508 nm, brazilin absorbance showed a good linear relationship in the range of 0‒6 μg (R2 = 0.9962). Precision RSD was no more than 3.40%, and recovery was between 100 and 105%. This novel TLC-based method has great potential for the quantitative assessment of brazilin. It is simpler, more reliable, and faster than HPLC-based analysis.

건선(Psoriasis)은 IL-6, CXCL8, TNF-α 및 IFN-γ뿐만 아니라 Th17 세포에서 분비되는 IL-17A 등 다양한 염증성 사이토카인에 의해 표피의 과증식(hyperkeratosis) 및 만성적 염증(inflammation)이 유발되는 난치성 피부 질환이다. 소목(Caesalpinia sappan L.)의 유효성분으로 알려진 브라질린(brazilin)은 항산화, 항염증 및 피부 장벽 개선 등의 효능이 알려졌다. 특히, tumor necrosis factor (TNF)-α 자극 HaCaT 각질형성세포 모델에서 브라질린의 건선 치료 소재 가능성을 보여주었다. 그러나, 직접적인 건선 유발 인자인 C-C motif chemokine ligand (CCL) 20의 조절은 전혀 보고되지 않았다. 따라서, 본 연구에서는 건선 유사 모델을 활용해 CCL20 발현 조절 여부 및 그 기작에 대해 규명하고자 하였다. IL-17A로 자극된 HaCaT 세포에서 브라질린은 CCL20, CXCL8 발현 및 signal transducer and transcription (STAT)3 인산화를 유의하게 억제하였다. 또한, 브라질린은 TNF-α/IL-17A/IFN-γ 3종 사이토카인으로 처리된 조건에서도 STAT3 인산화를 억제하며 염증성 분자(CXCL8, CCL20, IL-1, IL-6, 및 TNF-α)의 발현을 하향 조절하였다. 마지막으로 브라질린은 TNF-α/IL-17A/IFN-γ로 자극된 건선 유사 환경에서 피부 장벽 개선에도 유의적인 영향을 미쳤다. 위 결과들을 통해 우리는 궁극적으로 브라질린이 STAT3 인산화 억제를 통해 CCL20 발현을 하향 조절하며, 건선 유발 사이토카인들의 발현 또한 억제함을 알 수 있었다. 향후, 건선 동물모델 및 임상시험을 통해 브라질린의 건선 개선에 대한 효능이 검증된다면, 건선 환자에게 잠재적인 치료 물질로 사용될 수 있을 것으로 기대된다.

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.

Breast cancer is one of the leading causes of death worldwide. The pathway of breast cancer in KEGG shows that the most effective pathway is through the progesterone receptor (PR). Brazilin is a bioactive compound of secang (Caesalpinia sappan L.) used to inhibit breast cancer through survivin and Bcl-2 pathway but the interaction with PR route is unknown. This research was conducted to determine the virtual interaction between brazilin and PR and its comparison with lonaprisan, so the potential of breast cancer drugs that can overcome through three targets at once with minimal side effects is expected to be known. There are five docking interactions, including the interaction of PR-progesterone, PR-brazilin, PR-brazilin-progesterone, PR-lonaprisan, and PR-lonaprisan-progesterone. Protein and ligand preparation was performed by using Discovery Studio Client 2019 and PyRx 0.8, molecular docking was performed by using Hex 8.0.0 and visualization used Discovery Studio Client 2019. Virtual interaction results shows that lonaprisan has the most stable bond (lowest binding energy), -333.8kJ/mol but when progesterone was docked afterwards the result shows the opposite. Brazilin has a more stable bond compared to lonaprisan with a difference of 2.1kJ/mol and supported by hydrophobic bonds also capable of changing the position of progesterone in binding to PR so that it is estimated that brazilin has the potential as SPRMs, an alternative breast cancer drug to replace lonaprisan. Herbal medicine with brazilin can be estimated to fight breast cancer through 3 targets at once (survivin, Bcl-2, PR).

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), better known as the coronavirus, is a new type of coronavirus that is transmitted to humans This virus infection is called COVID-19 and was first discovered in the city of Wuhan, China, at the end of December 2019 This virus spread quickly and has spread to other regions in China and several countries, including Indonesia This disease results in coronavirus pandemic 2019-2020 The objective of this research is to determine the inhibitory ability of several active compounds from natural sources against COVID-19 target protein in silico using molecular docking In silico research was conducted using autodock 4 2 program by evaluating the binding energy between the active compound with ACE2, TMPRSS2, RdRp, 3CLpro and PLpro as the target proteins All chemical compounds that evaluated such as asiatic acid, andrographolide, apigenin, brazilein, brazilin, catechin, curcumin, gingerol, hesperidin, hesperetin, kaemferol, luteolin, myricetin, naringenin and quercetin had an affinity to target protein It reflects that active compounds in medicinal plants can be used as antiviral against COVID-19 Brazilein and brazilin from secang wood (Caesalpinia sappan L ) have a superior bond to ACE2 and lower binding energy value than chloroquine, arbidol, remdesivir, ribavirin and lopinavir Citrus sp containing hesperidin had an excellent affinity to TMPRSS2 Secang wood and citrus sp could be developed as an anti-SARS-CoV-2 through inhibiting ACE2, TMPRSS2, RdRp and protease (3CLpro and PLpro) that interfered the process of virus infection at the entry, replication and advanced stages, causing worst effect such as pneumonia

Until the recent past, the sole exemplar of proteins as infectious agents leading to neurodegenerative disorders remained the prion protein. Since then, the self-seeding mechanism characteristic of the prion protein has also been attributed to other neurodegenerative-disease-associated proteins, including amyloid-β (Aβ), tau, and α-synuclein (α-Syn). In model cell line studies, truncated Aβ, viz. amyloid beta (25-35), has been found to influence cellular homeostasis through its interactions with, and via, the disruption of key housekeeping machinery. Here, we demonstrate that the incubation of human neuroblastoma (SH-SY5Y) cell line with Brazilin ((6aS,11bR)-7,11b-dihydro-6H-indeno[2,1-c]chromene-3,6a,9,10-tetrol) prior to Aβ (25-35)-insult protected the cells from oxidative stress and apoptotic cell death. Furthermore, Brazilin mitigated Aβ-induced alterations in protein disulfide isomerase (PDI) and α-synuclein status, both of which are important biomarkers that report on Parkinson's pathogenesis. The results obtained in this study suggest that the tetrol is neuroprotective and helps resist Aβ-induced cross-pathology and amyloidogenic onset.

Amyloid-β (Aβ) oligomers are known as the most toxic form of Aβ peptides, and they are a major contributor to Alzheimer's disease. Therefore, developing antagonist screening methods for the formation of Aβ oligomers is urgent and of great interest. In this study, we introduce virtual oligomerization inhibition (VOI), a novel virtual screening protocol that applies atomistic simulation to quantitatively investigate the ability of a ligand in interfering Aβ oligomerization and the formation of Aβ oligomers. Results from the VOI performance on six known inhibitors of Aβ aggregation (brazilin, curcumin, EGCG, ELND005, resveratrol, and tacrine) are in excellent agreement with the results of expensive experiments. Moreover, VOI can reveal the mechanism and kinetics of the inhibition process at the atomistic level. VOI not only improves the efficiency of the antagonist screening for Aβ oligomerization but also reduces the cost of performing the task. Attractively, the principle of VOI can also be applied to inhibitor screening for the aggregation of other amyloid proteins/peptides.

The aim of this work was to identify the main chemical constituents and to evaluate the antilithiatic activity of the aqueous and hydroalcoholic extracts of stems of Caesalpinia bahamensis Lam. Fractionation and isolation of constituents from the hydroalcoholic extract was carried out by flash chromatography and semi-preparative liquid chromatography. The antilithiatic activity of the aqueous and hydroalcoholic extracts was evaluated in Wistar rats, where kidney stones were induced by ethylene glycol and ammonium chloride. Creatinine, calcium, and oxalate levels were evaluated and histological analysis was carried out. The homoisoflavonoids protosappanin B, 10-methyl-protosappanin B and brazilin were isolated and the antilithiatic activity of the aqueous and hydroalcoholic extracts was demonstrated by the reduction of the concentration of calcium and oxalate in urine compared to the lithiasis group. It was corroborated by histological analysis. Brazilin and protosappanin B were proposed as chemical markers for this plant species.

Cardiovascular diseases are the leading cause of death worldwide. The long-term aim of cardiovascular disease therapy is to reduce the mortality rate and decelerate the progression of cardiovascular organ damage. Current therapies focus on recovering heart function and reducing risk factors such as hyperglycemia and dyslipidemia. However, oxidative stress and inflammation are important causes of further damage to cardiovascular organs. Caesalpinia sappan Linn. (Fabaceae), a flowering tree native to tropical Asia, has antioxidant and anti-inflammatory properties. It is used as a natural dye to color food and beverages and as a traditional treatment for diarrhea, diabetes, and blood stasis. The phytochemical compounds in C. sappan, mainly the homoisoflavonoids brazilin, sappanone A, protosappanin, and hematoxylin, can potentially be used to protect cardiovascular organs. This review aims to provide updates on recent developments in research on C. sappan in relation to treatment of cardiovascular diseases. Many studies have reported protective effects of the plant’s bioactive compounds that reduce cardiac damage and enhance vasorelaxation. For example, brazilin and sappanone A have an impact on molecular and cellular changes in cardiovascular disease pathogenesis, mainly by modulating oxidative, inflammatory, and apoptotic signaling pathways. Therefore, bioactive compounds of C. sappan have the potential to be developed as therapeutic agents to combat cardiovascular diseases like myocardial infarction and vascular disease. This review could help further the understanding of the possible modulatory role of the compounds in cardiovascular diseases, thereby facilitating future studies.

Memory is an essential aspect of human cognition. A decrease in this aspect is well associated with Alzheimer’s disease (AD). The development of a novel cognitive enhancer (CE) may help overcome AD-related problems. In this study, we evaluated the CE effect of Caesalpinia sappan L. (CS) in memory deficit mice. Administration of its ethanolic extract (250 and 500 mg/kg body weight (BW)) and brazilin (5 and 10 mg/kg BW) ameliorated the scopolamine-amnesic effect, as evidenced by significant decreases (p &lt, 0.01, p &lt, 0.05) in the escape latency time and increases (p &lt, 0.01) in the percentage of time spent in the target quadrant of the Morris water maze test. We also examined the cyclic adenosine monophosphate (cAMP) level, protein kinase A (PKA) activity, and protein expression levels of phosphorylated cAMP response element binding (pCREB) and brain-derived neurotrophic factor (BDNF) in hippocampal tissues to elucidate the underlying molecular mechanism. Results showed that CS wood ethanolic extract and brazilin not only significantly increase (p &lt, 0.05) cAMP levels and PKA activity but also significantly enhance (p &lt, 0.05) the expression level of pCREB and BDNF in the hippocampus. These findings indicate that CS activates the cAMP/PKA/CREB/BDNF pathway. Taken together, our results demonstrate that CS is a promising herb that could be developed as a CE agent.

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.

Objective To clarify the active constituents of the heartwoods of Caesalpinia sappan, a traditional Chinese medicine with the functions of promoting blood circulation (Huoxue in Chinese) and removing blood stasis (Quyu in Chinese). Methods The chemical constituents were isolated and purified by combination of silica gel and Sephadex LH-20 column chromatography, along with semipreparative HPLC. Their chemical structures were established by multiple spectroscopic methods and comparison with literature data. The in vitro antiplatelet aggregation activities were evaluated using mouse platelet induced by AYPGKF-NH2, a gold agonist of protease-activated receptor 4 (PAR4). Results Two new phenols, methyl 2-(4,4′,5′-trihydroxy-2′-(methoxymethyl) biphenyl-2-yloxy) acetate (1) and 1′-methylcaesalpin J (2), together with 24 known compounds (3-26), were isolated from the heartwoods of C. sappan. Among them, sappanchalcone (16) and brazilin (20) showed inhibitory activities against mouse platelet aggregation with IC50 values of 114.8 μmol/L and 100.8 μmol/L, respectively. Conclusion Antiplatelet compounds from C. sappan targeting at PAR4 are reported for the first time.

Purpose: This study aimed to identify the whitening effect of brazilin on the B16F10 cell line. Methods: I measured the cell viability, mRNA expression, tyrosinase activity inhibition assay, and melanin contents assay from B16F10 cells. Also, I elucidated the effects of brazilin on tyrosinase-related protein 1 (TYRP1 )/TYRP2 / tyrosinase (TYR )/microphthalmia-associated transcription factor (MITF ) mRNA expression, and melanin production. Results: Quantitative real-time RT-PCR showed that brazilin decreased the mRNA level of TYRP1 /TYRP2 /TYR /MITF and melanin production compared with that of the MSH-treated B16F10 cells. The tyrosinase activity inhibition assay revealed that brazilin decreased melanin production in B16F10 cells. Conclusion: These data show that brazilin increases whitening effects in B16F10 cells and thus brazilin is a potent ingredient for skin whitening. Future studies based on these results can determine the potential uses of brazilin in cosmetics, health care, food, or medicine.

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.

Background Aberrant kallikrein activity is observed in a number of inflammatory dermatoses. Up-regulation of kallikrein-5 (KLK5) activity leads to uncontrolled skin desquamation and cleavage of proteinase-activated receptor-2 (PAR2), causing the release of pro-inflammatory cytokines and disruption of epidermal barrier function. This study aimed to identify KLK5-specific small molecule inhibitors which can serve as the foundation of a novel therapeutic for inflammatory skin disorders. Methods Five chemical libraries (13,569 compounds total) were screened against recombinant KLK5 using a fluorogenic enzymatic assay. Secondary validation was performed on the top 22 primary hits. All hits were docked in the KLK5 crystal structure to rationalize their potential interactions with the protein. Results A naturally occurring compound derived from the wood of Caesalpinia sappan (Brazilin) was identified as a novel KLK5 inhibitor (IC50: 20 μM, Ki: 6.4 μM). Docking suggests that the phenolic moiety of Brazilin binds in the S1-pocket of KLK5 and forms a H-bond with S195 side chain. KLK14 was also found to be susceptible to inhibition by Brazilin with a calculated IC50 value of 14.6 μM. Conclusions Natural KLK5 small molecule inhibitors such as Brazilin, are ideal for topical skin disease drug design and remain a promising therapeutic for severe cases of inflammatory skin disorders. Optimized KLK inhibitors may have increased efficacy as therapeutics and warrant further investigation.

Cancer is one of critical, chronic, and complex disease, also becoming the high cause of death in the world. Brazilin and brazilein in sappan wood (Caesalpinia sappan L.) and zerumbone in bitter ginger rhizome (Zingiber zerumbet L.) are known having cytotoxic activity with different mechanisms. This study aimed to examine combination effect of sappan wood and bitter ginger rhizome. Sappan wood and bitter ginger rhizomes macerated with ethanol 96% for 3x24 hours, filtered, and evaporated to obtain dried extract.Cytotoxic effect on MCF-7 cells was done using MTT assay. Combination Index (CI) was determined by CompuSyn based on the result of cytotoxic combination. Cell cycle profile and apoptosis induction was analyzed by flow cytometry. Sappan wood extracts and bitter ginger rhizome exhibited cytotoxic effects on MCF-7 cells with the IC50 values of 30 and 155 μg/mL respectively. The combination of sappan wood 15 μg/mL and bitter ginger 8, 12, 24, and 60 μg/mL produced synergistic effect with the CI value of 0.57-0.85. Sappan wood 15 μg/mL combined with bitter ginger 8 and 24 μg/mL showed cell cycle inhibition at G2/M phase. The combination also increased apoptosis induction compared to untreated cells and its single treatment.The combination of sappan wood ethanolic extracts and bitter ginger rhizome showed synergistic cytotoxic effect. Its synergism effect revealed through cell cycle arrested at G2/M phase and acceleration of apoptotic induction.

Background: Nature provides a rich source of antidiabetic medicines. More than 1.200 plants have been reported to have anti-diabetic activities and more than half of the drugs on the market come from natural products. Therefore, research for developing new antidiabetic drugs from natural sources is necessary to properly evaluate various mechanism of action, efficacy and safety at toxicological, physiological, pharmacological and molecular levels before these drugs applied in treatment of diabetes. This study aims to examine and determine the highest activity of 10 ethanol extracts from Indonesian plants selected for in vitro inhibitory activity of dipeptidyl peptidase - IV (DPP-IV). Materials and Methods: This research studied DPP-IV inhibitory mechanism from 10 plant extract, namely Caesalpinia sappan, Cinchona officinalis, Elephantopus scaber, Foeniculum vulgare, Morus nigra, Muntingia calabura, Phyllanthus niruri, Psidium guajava, Rheum palmatum and Vernonia amygdalina using the spectrophotometric method and Sitagliptin as a positive control. The effectiveness of inhibition was assessed by percent inhibition. Tannin removal test was performed to exclude false-positive results. Results: The ethanolic extract of Caesalpinia sappan exhibited DPP-IV inhibitory activity greater than 80%, which was not markedly different from that of Sitagliptin at 85%. Brazilin, an active compound from Caesalpinia sappan gave the inhibition at greater than 78%. Tannin removal test for Caesalpinia sappan gave the inhibition at 74.16%. The High Performance Liquid Chromatography (HPLC) analysis result displayed that brazilin content on Caesalpinia sappan extract was 91.94%. Conclusion: Based on these results, Caesalpinia sappan ethanol extract has a potential effect as a better antidiabetic agent than other extracts used in this study. Key words: Antidiabetic, DPP-IV, Caesalpinia sappan, Inhibitory activity.

Purpose: This study aimed to determine the skin anti-inflammatory effect of brazilin on RAW264.7 cells. Methods: To determine anti-inflammatory effects of brazilin on RAW264.7 cells, we measured cell viability, gene expressions, and prostaglandin E2 (PGE2)/nitric oxide (NO) production. Results: Cells were treated with brazilin to confirm cytotoxicity; no toxicity was observed when cells were treated at a concentration of ≤1 μg/mL. In RAW264.7 cells, the number of intracellular granule were increased after lipopolysaccharide (LPS) treatment; however, brazilin treatment decreased intracellular granules similar to that in the control group. In this research, we elucidated the anti-inflammatory effects of brazilin on the mRNA expression of interleukin 1 alpha (IL1α ), interleukin 1 beta (IL1β ), interleukin 6 (IL6 ), and tumor necrosis factor alpha (TNFα ) and PGE2/NO production. Real-time reverse transcription polymerase chain reaction (real-time RT-PCR) showed that brazilin administration increased the mRNA levels of IL1α /IL1β /IL6 /TNFα genes, and analysis of PGE2/NO also revealed that brazilin induces anti-inflammatory effects. Conclusion: We identified the anti-inflammatory effect of brazilin, and found that brazilin can be a potent cosmetic ingredient for anti-inflammatory agent for atopic dermatitis. Based on this result, we believe that brazilin has the potential to be used in not only cosmetics, but also medicine or healthcare food.

Alpha-synuclein (α-syn) fibrils, a major constituent of the neurotoxic Lewy Bodies in Parkinson's disease, form via nucleation dependent polymerization and can replicate by a seeding mechanism. Brazilin, a small molecule derived from red cedarwood trees in Brazil, has been shown to inhibit the fibrillogenesis of amyloid-beta (Aβ) and α-syn as well as remodel mature fibrils and reduce cytotoxicity. Here we test the effects of Brazilin on both seeded and unseeded α-syn fibril formation and show that the natural polyphenol inhibits fibrillogenesis of α-syn by a unique mechanism that alters conformational equilibria in two separate points of the assembly mechanism: Brazilin preserves the natively unfolded state of α-syn by specifically binding to the compact conformation of the α-syn monomer. Brazilin also eliminates seeding competence of α-syn assemblies from Parkinson's disease patient brain tissue, and reduces toxicity of pre-formed assemblies in primary neurons by inducing the formation of large fibril clusters. Molecular docking of Brazilin shows the molecule to interact both with unfolded α-syn monomers and with the cross-β sheet structure of α-syn fibrils. Our findings suggest that Brazilin has substantial potential as a neuroprotective and therapeutic agent for Parkinson's disease.

Caesalpinia sappan is studied for several biological activities. The aim of this research is to determine the cytotoxic and antimigratory activities of Caesalpinia sappan active fraction in combination with cisplatin on human TNBC cells (MDA-MB-231). Caesalpinia sappan heartwood was extracted with methanol. Then, several fractions of the methanol extract were obtained by using a liquid-liquid extraction method followed by column chromatography. The cytotoxicity was determined using MTT assay. Synergistic effects were analyzed by calculating the combination index (CI). Migration was examined using wound-healing assay. Levels of MMP2 activity were determined with gelatin zymography assay. The results showed that most of the fractions included in this study exhibited cytotoxic effects against MDA-MB-231 cells, and C fraction demonstrated the highest cytotoxic activity of all fractions. The combination of C-cisplatin revealed a synergistic inhibitory effect on MDA-MB-231 cell growth (CI

Alpha-synuclein (α-syn) fibrils, a major constituent of the neurotoxic Lewy Bodies in Parkinson’s disease, form via nucleation dependent polymerization and can replicate by a seeding mechanism. Brazilin, a small molecule derived from red cedarwood trees in Brazil, has been shown to inhibit the fibrillogenesis of amyloid-beta (Aβ) and α-syn, prompting our inquiry in its mechanism of action. Here we test the effects of Brazilin on both seeded and unseeded α-syn fibril formation and show that the natural polyphenol inhibits fibrillogenesis of α-syn by a unique mechanism that is distinct from other polyphenols and is also distinct from its effect on Aβ. Brazilin preserves the natively unfolded state of α-syn by stabilizing the compact conformation of the α-syn monomer over the aggregation-competent extended conformation. Molecular docking of Brazilin shows the molecule to interact both with unfolded α-syn monomers and with the cross-β sheet structure of α-syn fibrils. Brazilin eliminates seeding competence of α-syn assemblies from Parkinson’s disease patient brain tissue, and treatment of pre-formed fibril assemblies with Brazilin significantly reduces their toxicity in primary neurons. Our findings suggest that Brazilin has substantial potential as a neuroprotective and therapeutic agent for Parkinson’s Disease.Highlights- The natural polyphenol Brazilin binds to monomeric, oligomeric and fibrillar α-syn- Brazilin shifts the equilibrium away from aggregation-competent monomer conformations- Brazilin inactivates seeding-competent α-syn isolated from Parkinson patients’ brains- Brazilin detoxifies α-syn aggregation intermediates and stabilizes mature amyloid fibrilsGraphical Abstract

Cinnamon bark (Cinnamomum burmannii) and sappan wood (Caesalpinia sappan) have been reported to be beneficial for Type-2 Diabetes Mellitus (T2DM) and the combination is commonly used by Indonesian herbal industries. In the present study, the simultaneous extraction of bioactive compounds from both plants was conducted using natural deep eutectic solvent (NADES), their content analyzed using high-performance liquid chromatography (HPLC), and their dipeptidyl peptidase IV (DPP IV) inhibitory activity evaluated. An additional in silico molecular docking analysis was conducted to ensure their activity. The results showed that NADES (with a composition of choline chloride&ndash, glycerol) extraction from cinnamon and sappan wood had DPP IV inhibitory activity of 205.0 and 1254.0 &micro, g/mL, respectively. Brazilin as a marker substance from sappan wood was responsible for the DPP IV inhibitory activity, while none of the marker substances chosen for cinnamon bark (trans-cinnamaldehyde, coumarin, and trans-cinnamic acid) were found to have significant DPP IV inhibitory activity. These results were confirmed by molecular docking conducted in brazilin, trans-cinnamaldehyde, coumarin, and trans-cinnamic acid.

Cancer or uncontrolled cell proliferation is a major health issue worldwide and is the second leading cause of deaths globally. The high mortality rate and toxicity associated with cancer chemotherapy or radiation therapy have encouraged the investigation of complementary and alternative treatment methods, such as plant-based drugs. Moreover, over 60% of the anti-cancer drugs are molecules derived from plants or their synthetic derivatives. Therefore, in the present review, an attempt has been made to summarize the cytotoxic plants available in the Indian subcontinent along with a description of their bio-active components. The review covers 99 plants of 57 families as well as over 110 isolated bioactive cytotoxic compounds, amongst which at least 20 are new compounds. Among the reported phytoconstituents, artemisinin, lupeol, curcumin, and quercetin are under clinical trials, while brazilin, catechin, ursolic acid, β-sitosterol, and myricetin are under pharmacokinetic development. However, for the remaining compounds, there is little or no information available. Therefore, further investigations are warranted on these subcontinent medicinal plants as an important source of novel cytotoxic agents.

Brazilin and brazilein, the major compounds of Caesalpinia sappan L. (CS) have been reported to possess antioxidant and cytotoxic activities and could potentially be used as an antigenotoxic as well as an anticancer. This study was conducted to investigate the cytotoxic and antigenotoxic effects of CS ethanolic extract (CEE). In vivo mammalian micronucleus test of CEE at the dose of 500 mg/kg BW and 1000 mg/kg BW decreased the number of MNPCE and increased the ratio of PCE to NCE meaning that CEE performed antigenotoxic effect in an in vivo model. In contrast, CEE and doxorubicin (DOXO) performed cytotoxic effect on CHO-K1 cells under MTT assay with IC50 values of 67 μg/mL and 6 μM, respectively. Interestingly, treatment of CEE in combination with DOXO and H2O2 as genotoxic inducer decreased intracellular ROS levels. In addition, in vitro genotoxicity study by using cytokinesis-block micronucleus (CBMN) assay, both of Giemsa staining and flow cytometric analysis showed that the treatment of CEE increased the number of micronuclei and correlated with apoptotic induction results. Moreover, the combination of CEE and DOXO induced cells accumulation in Sub-G1 and G2/M phase. In conclusion, CEE performed antigenotoxic effect in an in vivo model and cytotoxic effect on CHO-K1 cells.

Purified Brazilin from Sappan wood extract has been reported with significant antitumor effect, especially on human T24 cells and bladder cancer mouse models. Brazilin can significantly induce expression of c-Fos and GADD45β and transfection expression of c-Fos and GADD45β in T24 cells can induce significant cell morphology changes, reduced viability and cell death, while transfection of siRNA-c-Fos and siRNA-GADD45β can reverse the induced cell death. Co-transfection of both c-Fos and GADD45β into T24 cells resulted in a significantly additive effect when compared to single transfection with only c-Fos or GADD45β. Meanwhile, transfection of interfering siRNA-c-Fos or siRNA-GADD45β can partially rescue the cell viability and siRNA co-transfection showed increased rescue rate. The transfection expression and interference with pcDNA3.1-c-Fos/siRNA-c-Fos or pcDNA3.1-GADD45β/siRNA-GADD45β did not affect each other's expression. Moreover, analysis of c-Fos and GADD45β regulated genes and signal pathways showed that no common regulated genes or pathways were present. All the results indicated that c-Fos and GADD45β mediate independent Brazilin-inducible genes and pathways. © 2018 IUBMB Life, 70(11):1101-1110, 2018.

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.

Purpose: Breast cancer cells with overexpression of HER2 are known to be more aggressive, invasive, and resistant to chemotherapeutic agent. Brazilin, the major compound in the Caesalpinia sappan L. (CS) heartwood, has been studied for it's anticancer activity. The purpose of this study was to investigate the cytotoxic and antimigratory activity of brazilin (Bi) in combination with doxorubicin (Dox) on MCF-7/HER2 cells. Methods: Cytotoxic activities of Bi individually and in combination with Dox were examined by MTT assay. Synergistic effects were analyzed by combination index (CI). Apoptosis and cell cycle profiles were observed by using flow cytometry. Migrating and invading cells were observed by using a Boyden chamber assay. Levels of MMP2 and MMP9 activity were observed by using a gelatin zymography assay. Levels of HER2, Bcl-2, Rac1, and p120 protein expression were observed by using an immunoblotting assay. Results: The results of the MTT assay showed that Bi inhibited MCF-7/HER2 cell growth in a dose-dependent manner with an IC50 of 54 ± 3.7 µM. Furthermore, the combination of Bi and Dox showed a synergistic effect (CI

Osteosarcoma is a common primary malignant bone tumour, and its cure rate has stagnated over the past 25–30 years. Brazilin, a purified natural product from sappan wood (Caesalpinia sappan L.), has been proved to possess potent anti-cancer effects. In this study, we investigated the anti-cancer effect of brazilin on human osteosarcoma and elucidated the underlying mechanisms. We exposed MG-63 cells to different concentrations of brazilin (5, 10 and 20 µM) for 24 h. Western blotting, immunocytofluorescence, luciferase reporter assays, and RT-PCR were used to evaluate whether brazilin activates FOXO family-dependent autophagy. Brazilin increased autophagic flux in the human osteosarcoma cell line MG-63, as evidenced by the upregulation of LC3-II and the downregulation of P62/SQSTM1. Moreover, the pharmacological or genetic blockade of autophagy decreased brazilin-induced cell death, indicating that brazilin triggered autophagic cell death in MG-63 cells. Specifically, brazilin induced FOXO3A(Ser7) phosphorylation, activated FOXO3A nuclear translocation and increased FOXO3A reporter activity, which contributed to the expression of autophagy-related genes and subsequently initiated autophagic cell death in MG-63 cells. Importantly, the increased expression and nuclear translocation of FOXO3A were tightly related to the disturbance of calcium homeostasis, which could be prevented by chelating intracellular calcium. Taken together, these data demonstrate that brazilin induces osteosarcoma cell death by inducing excessive autophagy, which is mediated through the Ca2+-FOXO3A pathway. Our study provides a new anti-tumour mechanism for brazilin treatment in osteosarcoma patients.

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.

This article contains data on in vitro cytotoxicity activity of chloroform, methanolic and water extracts of leaf and heartwood of Caesalpinia sappan L. a medicinal plant against Breast cancer (MCF-7) and Lung cancer (A-549) cells. This data shows that Brazilin A, a natural bioactive compound in heartwood of Caesalpinia sappan L.induced cell death in breast cancer (MCF-7) cells. The therapeutic property was further proved by docking the Brazilin A molecule against BCL-2 protein (an apoptotic inhibitor) using auto dock tools. Keywords: Chloroform extract, Methanol extract, Water extract, Caesalpinia sappan L., Cytotoxicity, MCF7, A549, MTT Assay

Brazilin, the major constituent from the heartwood of Caesalpinia sappan, has been widely used as a natural red color dye or food ingredient and drug. However, the application of brazilin is greatly restricted by its low stability. In this study, the preparation, characterization, inclusion mode, stability and solubility of brazilin with hydroxypropyl-β-cyclodextrin (HPβCD) were studied for the first time in both the solid state and solution by means of XRD, DSC, SEM, 1H and 2D NMR and UV–vis spectroscopy. The molecular modelling demonstrated the most stable inclusion model of brazilin/HPβCD complex. The results illustrated that the stability of brazilin were improved in the inclusion complex with HPβCD. This satisfactory characterization and stability of the brazilin/HPβCD complex should be possibly useful for its utilization as dye, food or drug.

Caesalpinia sappan L., belonging to the family Leguminosae, is a medicinal plant that is distributed in Southeast Asia. The dried heartwood of this plant is used as a traditional ingredient of food, red dyes, and folk medicines in the treatment of diarrhea, dysentery, tuberculosis, skin infections, and inflammation. Brazilin is the major active compound, which has exhibited various pharmacological effects, including anti-platelet activity, anti-hepatotoxicity, induction of immunological tolerance, and anti-inflammatory and antioxidant activities. The present study aimed to evaluate the antioxidant activity and expression of antioxidant enzymes of C. sappan L. extract and its major compound, brazilin, in human epidermal keratinocytes exposed to UVA irradiation. Our results indicated that C. sappan L. extract reduced UVA-induced H2O2 production via GPX7 activation. Moreover, brazilin exhibited antioxidant effects that were similar to those of C. sappan L. via glutathione peroxidase 7 (GPX7), suggesting that C. sappan L. extract and its natural compound represent potential treatments for oxidative stress-induced photoaging of skin.

A chemical backbone of tetracyclic homoisoflavanoid natural products such as brazilin inspired us to design a new chemical scaffold, 6a,11b-dihydroindeno[2,1-c]chromen-7(6H)-one, which is a hybrid structure of indanone and chromane. Pd-catalyzed Suzuki-Miyaura cross-coupling of 4-chloro-2H-chromene-3-carbaldehydes with (hetero)aryl boronic acids was employed as a means to introduce a wide variety of (hetero)aryl groups as the D ring and intramolecular Friedel-Crafts acylation was utilized to construct the C ring of this skeleton. Total synthesis of the natural product, brazilane, was also demonstrated via this new chemical framework.

Dye from Sappang Tree has been isolated using ethanol as a solvent. Braziline is one of the chemical compound found in the ethanol extract. The Compound can be used as anion calorimethric due to their active sites of hydroxyl and chromophore groups. Dyes from sappang tree has been tested on 10 g of several types of saturated anions (carbonate, sulfate, phosphate, cyanide, acetate, borax, nitrite, chloride, bromide, and iodide). The results of the tests show that the color of the dye from changes in carbonate, phosphate, cyanide, acetate, nitrite, and hydroxyl. Spectrophotometer UV/Vis is used to detect the limit of cyanide anion. Metanol and acetone show positive results on the dye in cyanide anion. Detection limit of braziline is 3x10 -4 M. By addition of cyanide anion, the dye has detection limit at 1x10 -4 M.

Interactions of Zn2+ with amyloid β-protein (Aβ) and the subsequent induction of Aβ aggregation have been implicated in the pathogenesis of Alzheimer's disease (AD). The development of small-compound inhibitors against Zn2+-mediated Aβ aggregation is therefore greatly desired. In this study, brazilin was used to inhibit Zn2+-mediated Aβ aggregation and alleviate its cytotoxicity. The binding properties of brazilin and Zn2+ were first probed using Fourier transform infrared (FTIR) spectroscopy and isothermal titration calorimetry (ITC) assays. Both the FTIR and ITC results have shown that brazilin is able to bind Zn2+ in a physiologically suitable range of concentrations. The dissociation constant (Kd) between brazilin and Zn2+ was about 46.0±6.8μM, which makes brazilin a potential drug model for the chelation of free Zn2+. Moreover, the higher affinity of brazilin for Aβ42 (Kd=2.5±1.6μM) than that of Zn2+ (Kd=6.2±0. 9μM), enables brazilin to sequester Zn2+ from the Aβ42-Zn2+ complex. In addition, the inhibitory effects of brazilin on Zn2+-mediated Aβ aggregation were examined using the Thioflavin T fluorescence assay, transmission electron microscopy and cytotoxicity assays. It was found that brazilin showed remarkable inhibitory capability against Zn2+-induced aggregation of Aβ42. Furthermore, the Zn2+-mediated cytotoxicity of Aβ42 was also largely mitigated under the influence of brazilin. This study therefore provides further insights into the role of Zn2+ in the Aβ42 aggregation pathway, indicating potential new strategies for the design of small compounds with therapeutic potential for AD.

One of the mechanisms of cancer cell resistance toward chemotherapy is through cancer stem cells (CSCs), which are characterized by excessive activation of regulator proteins such as human epidermal receptor 2 (HER2). Sappan wood (Caesalpinia sappan L.) contains brazilin and brazilein that exhibit cytotoxic effects on several cancer cell lines. We aimed to explore the potency of the ethanolic extract of sappan (EES) in CSCs through bioinformatic analyses and by using a three-dimensional (3D) breast cancer stem cells (BCSCs) for in vitro assay with two different models (i.e., BCSCs and HER2-BCSCs) in order to identify the potential therapeutic targets of genes (PTTGs). Bioinformatic analyses identified PTTGs, which were further analyzed by gene ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, protein-protein interaction (PPI) networks, and hub protein selection. Mammospheres were cultured under conditioned media. The cytotoxic effects of EES were then measured by direct counting and based on the mammosphere-forming potential (MFP). Bioinformatic analysis disclosed PIK3CA and TP53 as PTTGs in BCSCs and HER2-BCSCs, respectively. In addition, the KEGG pathway analyses also demonstrated that PTTGs could regulate the ERBB pathway. EES thus demonstrated cytotoxicity and inhibited the formation of mammospheres. Collectively, EES exhibited excellent potential for further development as an inhibitor of cancer stem cells in breast cancer.

Sappanwood (Caesalpinia sappan L) is a member of Leguminosae plant, which is popular for its function as a natural source of red dye and has been traditionally used to prepare food and beverage in Southeast Asia. From the pharmacological point of view, the heartwood extract of this plant exhibits various biological activities, such as antibacterial, anti-photoaging, anti-allergic, anti-inflammatory, antioxidant, etc. Brazilin as the main antioxidant compound can be efficiently extracted by the ultrasound-assisted extraction (UAE) method. This study aimed to evaluate the effect of temperature (30 to 60°C), time (5 to 25 minutes), and solid-liquid ratio (1:5 to 1:8 g/mL) on the batch ultrasound-assisted extraction of antioxidant compounds from sappanwood heartwood. The results showed that the feasible extraction process was at 30°C using the solid-liquid ratio of 1:5 g/mL for 15 minutes to obtain an extract yield of 3.0%. The yield was 1.50 times compared to the conventional extraction without ultrasound. The increase in temperature and solvent resulted in higher yields. However, considering the energy for extraction and product purification, extraction at ambient temperature with minimum solvent volume was favorable. Meanwhile, the pseudo-second-order mass transfer model exhibited good statistical parameters, and R2 was higher than 0.99 with lower RSMD values. This model can be used to describe the kinetics of UAE of antioxidant compounds from sappanwood. The model was meaningful in determining the efficient extraction time with reasonable antioxidant performance.

Brazilin (Bra), hematoxylin (Hto) and hematein (Hte) are structurally similar polyphenols having rich biological activities, but their antioxidant ability has not been well studied. Here, their protective ability against human serum albumin (HSA) oxidative degradation were investigated using 2,2′-Azobis (2-methylpropionamidine) dihydrochloride (AAPH), NaClO and Fenton like reactions methods. The results indicated that polyphenols inhibited the oxidative injuries of HSA in the order: Hto > Bra > Hte. Additionally, the biological effects of polyphenols were mostly influenced by their binding to protein. Therefore, the structure-affinity relationships of polyphenols binding to HSA were also explored. Fluorescence experiments indicated that polyphenols bound to HSA through static quenching mechanism. Furthermore, some conformational changes of HSA could be observed in the presence of polyphenols. Altogether, molecular structure of polyphenols played a significant role in their protective effect against HSA oxidative damage and binding ability, which provided fundamental insights into their application as health care foods.

Purpose: The aim of this study is to observe the synergistic effect of two active compounds of secang, brazilin and brazilein, combined with cisplatin on WiDr colon cancer cells. Methods: Cytotoxic activities of brazilin (Bi) and brazilein (Be) in single and in combination with cisplatin (Cisp) were examined by MTT assay. Synergistic effect was analyzed by combination index (CI) parameter. Apoptosis and cell cycle profiles were observed by using flow cytometry. Results: The result of MTT assay showed that IC50 value of brazilin and brazilein on WiDr cancer cells were 41 µM and 52 µM respectively. The combination of ½ IC50 of Bi-Cisp reduced cells viability up to 64% and showed synergistic effect with CI value less than 1 (CI = 0.8). The combinations of ½ IC50 of Be-Cisp also reduced cells viability up to 78% and showed synergistic effect (CI=0.65). Combination of Bi-Cisp and Be-Cisp induced apoptosis higher than the single treatments. Further analysis on the cell cycle progression showed that single treatment of ½ IC50 of Be and Bi induced S-phase and G2/M-phase accumulation, while combination of Be-Cisp and Bi-Cisp enhanced S-phase accumulation. Conclusion: Both combination of Bi-Cisp and Be-Cisp showed synergistic effect on WiDr cells through induction of apoptosis and halted the cell cycle progression, thus, WiDr cells growth were significantly reduced.

Hyperglycemia and inflammation play important roles in the pathogenesis of diabetic nephropathy (DN). Brazilin might be an effective pharmacological agent against hyperglycemia and inflammation. In our present study, we explored whether brazilin mitigated pathological progression, inflammation, and extracellular matrix (ECM) accumulation in a mouse model of diabetic nephropathy. Brazilin reduced aggravated biochemical indices of DN (proteinuria and the serum glucose level) and renal hypertrophy. Brazilin also improved renal morphology and inhibited macrophage infiltration, as manifested by different pathological staining methods. Brazilin reduced the levels of pro-inflammatory cytokines and CD68, a macrophage marker, in the kidney cortex, as revealed by both RT-PCR and western blotting experiments. Furthermore, brazilin significantly downregulated the serum levels of pro-inflammatory cytokines and chemokines. Interestingly, brazilin significantly upregulated the levels of the anti-inflammatory factor IL-10, and prevented ECM accumulation. Brazilin reduced nuclear translocation of the NF-κB p65 subunit both in vitro and in vivo. Thus, brazilin might be a useful treatment for DN, through mitigating hypoglycemia, inflammation, and ECM accumulation.

Autophagy modulation has been considered a potential therapeutic strategy for head and neck squamous cell carcinoma (HNSCC). A previous study confirmed that brazilin might possess significant anti-carcinogenic activity. However, whether brazilin induces autophagy and its roles in cell death in HNSCC are still unclear. In this study, we have shown that brazilin induced significant apoptosis in the Cal27 HNSCC cell line but not in oral keratinocyte cell line (OKC). In addition to showing apoptosis induction, we demonstrated the brazilin-induced autophagic response in the Cal27 cells, as evidenced by the formation of GFP-LC3 puncta, and also showed the upregulation of LC3-II and Beclin-1. Moreover, pharmacologically or genetically blocking autophagy enhanced the brazilin-induced apoptosis, indicating the cytoprotective role of autophagy in brazilin-treated Cal27 cells. Moreover, brazilin activated nuclear factor kappa B (NF-κB p65) nuclear translocation and increased NF-κB p65 reporter activity, which contributed to the upregulation of autophagy-related genes, including LC3-II and Beclin-1. Importantly, we found that brazilin triggered reactive oxygen species (ROS) generation in Cal27 cells. Furthermore, N-acetyl-cysteine (NAC), a ROS scavenger, abrogated the effects of brazilin on the NF-κB p65-dependent autophagy. Taken together, our results demonstrated that brazilin increased the NF-κB p65-dependent autophagy through the promotion of ROS signalling pathways in HNSCC. These data also suggest that a strategy of blocking ROS-NF-κB p65-dependent autophagy to enhance the activity of brazilin warrants further attention for the treatment of HNSCC.

In the study, hair colouring by utilising enzymatic oxidation of nine species of bio-catechols, which are biobased materials having the catechol (o-dihydroxybenzene) group, was examined. The bio-catechols used are (+)-catechin (Cat), (-)-epicatechin (EC), L-3,4-dihydroxyphenylalanine (DOPA), hematoxylin (HX), brazilin (BZ), rosmarinic acid (RA), caffeic acid (CA), chlorogenic acid (ChA) or ellagic acid (EA). The dyeability of human white hair samples dyed by two kinds of dyeing methods using the bio-catechols was compared. First one is dyeing hair during the enzymatic oxidation of a bio-catechol dye precursor in a dye solution (simultaneous oxidation dyeing method). Second one is dyeing hair by oxidising enzymatically the precursor on hair, which is pre-treated with a bio-catechol solution (post-oxidation dyeing method). The results show that the bio-catechols except EA are oxidised to give colourants and Cat, EC, DOPA, HX and BZ are available for hair dyeing. Overall, the dyeability of simultaneous oxidation dyeing method is higher than that of post-oxidation one. The colour of the hair dyed by simultaneous method is yellowish brown for Cat or EC, grey for DOPA, dark yellowish brown for HX or reddish brown for BZ, respectively. The most vivid or deepest colour of dyed hair is obtained by dyeing with Cat or HX, respectively, in the simultaneous technique. It was found that the bio-catechols having chroman (3, 4-dihydro-2H-1-benzopyran) structure in the molecule such as Cat, EC, HX and BZ are useful for hair colouring.

Fibrillogenesis of human islet amyloid polypeptide (hIAPP) is a pathological hallmark of type II diabetes mellitus (T2DM), and the inhibition of hIAPP fibrillogenesis is an important strategy for the prevention and treatment of T2DM. In this study, the inhibitory effects of brazilin on the fibrillization and cytotoxicity of hIAPP were examined using the thioflavin T fluorescence (ThT) assay, transmission electron microscopy (TEM), circular dichroism (CD) spectroscopy, cytotoxicity assays, and molecular dynamics simulations. Both the ThT and TEM results have shown that brazilin inhibits hIAPP fibrillogenesis in a dose-dependent manner. CD studies revealed that brazilin delays the conformational transition of hIAPP from its initial α-helical to the β-sheet form. As a result, brazilin greatly alleviates hIAPP-induced cytotoxicity. Moreover, we also found that brazilin disassembles preexisting hIAPP fibrils, and alleviates the cytotoxicity of hIAPP aggregates. The results of free energy decomposition studies calculated using molecular mechanics-Poisson–Boltzmann surface area analysis revealed that hydrophobic interactions contribute more than 75% of the free energy of binding in the brazilin–hIAPP complex, while electrostatic interactions (i.e., hydrogen bonds) play a secondary role (