ECDD-S16 targets vacuolar ATPase: A potential inhibitor compound for pyroptosis-induced inflammation.

BACKGROUND: Cleistanthin A (CA), extracted from Phyllanthus taxodiifolius Beille, was previously reported as a potential V-ATPase inhibitor relevant to cancer cell survival. In the present study, ECDD-S16, a derivative of cleistanthin A, was investigated and found to interfere with pyroptosis induction via V-ATPase inhibition. OBJECTIVE: This study examined the ability of ECDD-S16 to inhibit endolysosome acidification leading to the attenuation of pyroptosis in Raw264.7 macrophages activated by both surface and endosomal TLR ligands. METHODS: To elucidate the activity of ECDD-S16 on pyroptosis-induced inflammation, Raw264.7 cells were pretreated with the compound before stimulation with surface and endosomal TLR ligands. The release of lactate dehydrogenase (LDH) was determined by LDH assay. Additionally, the production of cytokines and the expression of pyroptosis markers were examined by ELISA and immunoblotting. Moreover, molecular docking was performed to demonstrate the binding of ECDD-S16 to the vacuolar (V-)ATPase. RESULTS: This study showed that ECDD-S16 could inhibit pyroptosis in Raw264.7 cells activated with surface and endosomal TLR ligands. The attenuation of pyroptosis by ECDD-S16 was due to the impairment of endosome acidification, which also led to decreased Reactive Oxygen Species (ROS) production. Furthermore, molecular docking also showed the possibility of inhibiting endosome acidification by the binding of ECDD-S16 to the vacuolar (V-)ATPase in the region of V0. CONCLUSION: Our findings indicate the potential of ECDD-S16 for inhibiting pyroptosis and prove that vacuolar H+ ATPase is essential for pyroptosis induced by TLR ligands.

Black ginger extract and its active compound, 5,7-dimethoxyflavone, increase intestinal drug absorption via efflux drug transporter inhibitions.

Black ginger is used as an herbal medicine for self-care and health promotion. Black ginger extract has been shown to alter the function of transporters in several cell types. This study demonstrates the interaction between the extract and 5,7-dimethoxyflavone (DMF) on drug efflux mediated by breast cancer resistance proteins (BCRP) and P-glycoprotein (P-gp) in Caco-2 cells and heterologous cell systems [Madin-Darby canine kidney type II (MDCKII) stably transfected with human BCRP (MDCKII/BCRP) or human P-gp (MDCKII/P-gp)]. The transepithelial flux of 3H-Digoxin and 3H-Estrone sulfate, prototypic substrates of P-gp, and BCRP, respectively, across Caco-2 cell monolayers, MDCKII/BCRP, and MDCKII/P-gp cells were determined. The results demonstrate that black ginger extract (10 µg/ml) significantly increases 3H-Digoxin and 3H-Estrone sulfate transport from the apical to basolateral side while decreasing transport from the basolateral to apical side of Caco-2 cells and MDCKII cell overexpression of BCRP or P-gp. The effect of the extract on 3H-Digoxin and 3H-Estrone sulfate transport was related to a decrease in efflux ratio. Likewise, DMF (5 µM) significantly increased 3H-Digoxin and 3H-Estrone sulfate absorption with a decreased efflux ratio compared to the control. Interestingly, the extract also significantly increased absorption of paclitaxel, an anti-cancer drug, which has poor oral absorption. Taken together, co-administration of drugs as substrates of BCRP and P-gp, with the black ginger extract containing DMF, might alter the pharmacokinetic profiles of the medicine.

Phyllanthus taxodiifolius Beille Disrupted N-cadherin, Vimentin, Paxillin and Actin Stress Fibers in Glioblastoma.

OBJECTIVE: Glioblastoma is the most aggressive and lethal brain tumor in adults with highly invasive properties. In this present study, we explored the effects of Phyllanthus taxodiifolius Beille extract on molecules known to be hallmarks of aggressive glioblastoma including N-cadherin and vimentin, mesenchymal markers, as well as paxillin, a major adaptor protein that regulates the linking of focal adhesions to the actin cytoskeleton. METHODS: P. taxodiifolius were air-dried, powdered and percolated with methanol, filtered, concentrated and lyophilized to yield a crude methanol extract. C6 glioblastoma cell line was used in this study. The expression of N-cadherin and vimentin, as well as the activation of paxillin was determined using Western blot analysis. The effect of the extract on focal adhesions and actin cytoskeleton were investigated using immunofluorescence staining and confocal imaging. RESULTS: In the presence of 40 µg/ml Phyllanthus taxodiifolius Beille extract, the expression of N-cadherin and vimentin were significantly decreased (p<0.001 and p<0.05, respectively). Activation of paxillin was also diminished as indicated by a reduction of phosphorylated-paxillin (p<0.01). Consequently, actin stress fibers in glioblastoma cells were abolished as evidenced by the decrease in focal adhesion (p<0.001) and stress fibers numbers (p<0.001). CONCLUSION: Our study demonstrates for the first time that P. taxodiifolius interferes with multiple key molecules related to pathological hallmarks of glioblastoma. These molecules are involved with cell contacts, focal adhesions, and the formation and stabilization of actin stress fibers, which are required for glioblastoma metastatic behavior. These results provide further evidence supporting the potential of P. taxodiifolius and its bioactive compounds as anti-cancer agents.

Pharmacological Effects of Panduratin A on Renal Cyst Development in In Vitro and In Vivo Models of Polycystic Kidney Disease.

Renal cyst expansion in polycystic kidney disease (PKD) involves abnormalities in both cyst-lining-cell proliferation and fluid accumulation. Suppression of these processes may retard the progression of PKD. Evidence suggests that the activation of 5' AMP-activated protein kinase (AMPK) inhibits cystic fibrosis transmembrane conductance regulator (CFTR)-mediated chloride secretion, leading to reduced progression of PKD. Here we investigated the pharmacological effects of panduratin A, a bioactive compound known as an AMPK activator, on CFTR-mediated chloride secretion and renal cyst development using in vitro and animal models of PKD. We demonstrated that AMPK was activated in immortalized normal renal cells and autosomal dominant polycystic kidney disease (ADPKD) cells following treatment with panduratin A. Treatment with panduratin A reduced the number of renal cyst colonies corresponding with a decrease in cell proliferation and phosphorylated p70/S6K, a downstream target of mTOR signaling. Additionally, panduratin A slowed cyst expansion via inhibition of the protein expression and transport function of CFTR. In heterozygous Han:Sprague-Dawley (Cy/+) rats, an animal model of PKD, intraperitoneal administration of panduratin A (25 mg/kg BW) for 5 weeks significantly decreased the kidney weight per body weight ratios and the cystic index. Panduratin A also reduced collagen deposition in renal tissue. Intraperitoneal administration of panduratin A caused abdominal bleeding and reduced body weight. However, 25 mg/kg BW of panduratin A via oral administration in the PCK rats, another non-orthologous PKD model, showed a significant decrease in the cystic index without severe adverse effects, indicating that the route of administration is critical in preventing adverse effects while still slowing disease progression. These findings reveal that panduratin A might hold therapeutic properties for the treatment of PKD.

Nephroprotective potential of Panduratin A against colistin-induced renal injury via attenuating mitochondrial dysfunction and cell apoptosis.

Colistin is a last-resort polypeptide antibiotic widely used to treat against multidrug-resistant Gram-negative bacterial infections. However, this treatment is associated with nephrotoxicity. The aim of this study was to examine the potential protective effect of panduratin A, a bioactive compound of Boesenbergia rotunda, on colistin-induced nephrotoxicity in both in vivo and in vitro models. Intraperitoneal injection of 15 mg/kg colistin for 7 days markedly promoted renal tubular degeneration, increased blood urea nitrogen (BUN) levels, and upregulated the expression of renal injury biomarker and apoptosis proteins. In addition, treatment with colistin increased oxidative stress and apoptosis in mice kidney tissues. Interestingly, these defects were attenuated when co-administered of colistin with panduratin A (2.5 or 25 mg/kg). The underlying mechanisms of panduratin A attenuating colistin toxicity was investigated in human renal proximal tubular cells (RPTEC/TERT1). The mechanisms by which colistin-triggered cytotoxicity was determined by analysis of cell death, reactive oxygen species (ROS) levels, mitochondria function as well as the expression of proteins related to apoptosis pathway. Colistin treatment (200 µg/ml) significantly increased cell apoptosis, elevated ROS production, reduced mitochondrial membrane potential, and decreased anti-apoptotic protein (Bcl-2) expression. These effects were notably suppressed by co-treatment with panduratin A (5 µM). Collectively, panduratin A exerts as a novel nephroprotective agent to protect against colistin-induced renal injury by attenuating mitochondrial damage and renal cell apoptosis.

Suppression of PI3K/Akt/mTOR pathway in chrysoeriol-induced apoptosis of rat C6 glioma cells.

Chrysoeriol, a dietary methoxyflavonoid which is found in tropical medicinal plants, has been shown to have antioxidant, anti-inflammatory, and antineoplastic properties. The present study aimed to investigate the effects of chrysoeriol and its related mechanisms in rat C6 glioma cells. Cell viability in rat C6 glioma cells were measured by MTT assay. The protein expression levels of cleaved caspase-3, caspase-3, pro-apoptotic (Bax), anti-apoptotic protein (Bcl-2), and Annexin V were detected by Western blot analysis and immunocytochemical staining. Results showed that chrysoeriol significantly decreased cell viability and induced apoptosis in rat C6 glioma cells. Chrysoeriol significantly increased the levels of Bax/Bcl-2 ratio and cleaved caspase-3/caspase-3 ratio. Moreover, treatment with chrysoeriol significantly reduced the phosphorylation of PI3K, Akt, and mTOR expression in ratios. These results suggest that chrysoeriol promote apoptosis in rat C6 glioma cells via suppression of the PI3K/Akt/mTOR signaling pathway, thereby demonstrating the potential antineoplastic effects of chrysoeriol on glioma cells.

Panduratin A Derivative Protects against Cisplatin-Induced Apoptosis of Renal Proximal Tubular Cells and Kidney Injury in Mice.

BACKGROUND: Panduratin A is a bioactive cyclohexanyl chalcone exhibiting several pharmacological activities, such as anti-inflammatory, anti-oxidative, and anti-cancer activities. Recently, the nephroprotective effect of panduratin A in cisplatin (CDDP) treatment was revealed. The present study examined the potential of certain compounds derived from panduratin A to protect against CDDP-induced nephrotoxicity. METHODS: Three derivatives of panduratin A (DD-217, DD-218, and DD-219) were semi-synthesized from panduratin A. We investigated the effects and corresponding mechanisms of the derivatives of panduratin A for preventing nephrotoxicity of CDDP in both immortalized human renal proximal tubular cells (RPTEC/TERT1 cells) and mice. RESULTS: Treating the cell with 10 µM panduratin A significantly reduced the viability of RPTEC/TERT1 cells compared to control (panduratin A: 72% ± 4.85%). Interestingly, DD-217, DD-218, and DD-219 at the same concentration did not significantly affect cell viability (92% ± 8.44%, 90% ± 7.50%, and 87 ± 5.2%, respectively). Among those derivatives, DD-218 exhibited the most protective effect against CDDP-induced renal proximal tubular cell apoptosis (control: 57% ± 1.23%; DD-218: 19% ± 10.14%; DD-219: 33% ± 14.06%). The cytoprotective effect of DD-218 was mediated via decreases in CDDP-induced mitochondria dysfunction, intracellular reactive oxygen species (ROS) generation, activation of ERK1/2, and cleaved-caspase 3 and 7. In addition, DD-218 attenuated CDDP-induced nephrotoxicity by a decrease in renal injury and improved in renal dysfunction in C57BL/6 mice. Importantly, DD-218 did not attenuate the anti-cancer efficacy of CDDP in non-small-cell lung cancer cells or colon cancer cells. CONCLUSIONS: This finding suggests that DD-218, a derivative of panduratin A, holds promise as an adjuvant therapy in patients receiving CDDP.

Preparation and Characterization of MUC-30-Loaded Polymeric Micelles against MCF-7 Cell Lines Using Molecular Docking Methods and In Vitro Study.

MUC-30 is a hydrophobic compound which is active against the MCF-7 cancer cell line. In this study, MUC-30 was loaded in polymeric micelles to improve the water solubility and release rate. For prolonged MUC-30 release, MUC-30 was encapsulated in polymeric micelles using PEG-b-PLA and PEG-b-PCL as materials. Micelles prepared with 1 : 9 w per w ratios by film hydration achieved the highest entrapment efficiency (EE%). The EE% of MUC-30-loaded PEG-b-PCL micelles was approximately 30% greater than that of PEG-b-PLA micelles, due to the different H-bond formations between MUC-30 and the polymer membrane (PCL, 4; PLA, 3). The cytotoxic activity of MUC-30 against EGFR theoretically presented 399.31 nM (IC50 = 282.26 ng/mL) by molecular docking. In vitro cytotoxic activity of MUC-30 was confirmed by MTT assay. MUC-30 (IC50 = 11 ± 0.39 ng/mL) showed three-fold higher activity over MUC-30-loaded PEG-b-PLA micelles (IC50 = 37 ± 1.18 ng/mL) and two-fold higher over PEG-b-PCL micelles (IC50 = 75 ± 3.97 ng/mL). This was due to the higher release rate of MUC-30 from PEG-b-PLA micelles compared to PEG-b-PCL micelles. Therefore, MUC-30-loaded PEG-b-PLA micelles could be a promising candidate for breast cancer chemotherapy.

Protective Effect of Panduratin A on Cisplatin-Induced Apoptosis of Human Renal Proximal Tubular Cells and Acute Kidney Injury in Mice.

BACKGROUND: Cisplatin is an effective chemotherapy but its main side effect, acute kidney injury, limits its use. Panduratin A, a bioactive compound extracted from Boesenbergia rotunda, shows several biological activities such as anti-oxidative effects. The present study investigated the nephroprotective effect of panduratin A on cisplatin-induced renal injury. METHODS: We investigated the effect of panduratin A on the toxicity of cisplatin in both mice and human renal cell cultures using RPTEC/TERT1 cells. RESULTS: The results demonstrated that panduratin A ameliorates cisplatin-induced renal toxicity in both mice and RPTEC/TERT1 cells by reducing apoptosis. Mice treated with a single intraperitoneal (i.p.) injection of cisplatin (20 mg/kg body weight (BW)) exhibited renal tubule injury and impaired kidney function as shown by histological examination and increased serum creatinine. Co-administration of panduratin A (50 mg/kg BW) orally improved kidney function and ameliorated renal tubule injury of cisplatin by inhibiting activation of extracellular signal-regulated kinase (ERK)1/2 and caspase 3. In human renal proximal tubular cells, cisplatin induced cell apoptosis by activating pro-apoptotic proteins (ERK1/2 and caspase 3), and reducing the anti-apoptotic protein (Bcl-2). These effects were significantly ameliorated by co-treatment with panduratin A. Interestingly, panduratin A did not alter intracellular accumulation of cisplatin. It did not alter the anti-cancer efficacy of cisplatin in either human colon or non-small cell lung cancer cell lines. CONCLUSIONS: The present study highlights panduratin A has a potential protective effect on cisplatin's nephrotoxicity.

Bioactive tetrahydrofuran lignans from roots, stems, leaves and twigs of Anogeissus rivularis.

Four previously undescribed tetrahydrofuran lignans, named anorisols A-D (1-4) and fourteen known compounds (5-18) were isolated from the roots, stems, leaves and twigs of Anogeissus rivularis. The chemical structures were elucidated on the basis of their spectroscopic data and by comparison with the literature data. The absolute configurations of 1-4 were established by comparison of the experimental ECD spectra with the calculated ECD spectra. Some isolated compounds were evaluated for their cytotoxic activity as well as anti-HIV-1 activity employing reverse transcriptase (RT) and syncytium reduction assays using the ΔTat/RevMC99 virus in 1A2 cell line systems. Compound 6 displayed the most potent activity in syncytium inhibition assay with effective concentration at 50% (EC50) value of 13.3 µM (SI >3.0). In the reverse transcriptase assay, compound 1 exhibited moderate activity with IC50 value of 213.9 µM.

High-content screening of Thai medicinal plants reveals Boesenbergia rotunda extract and its component Panduratin A as anti-SARS-CoV-2 agents.

Since December 2019, the emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused severe pneumonia, a disease named COVID-19, that became pandemic and created an acute threat to public health. The effective therapeutics are in urgent need. Here, we developed a high-content screening for the antiviral candidates using fluorescence-based SARS-CoV-2 nucleoprotein detection in Vero E6 cells coupled with plaque reduction assay. Among 122 Thai natural products, we found that Boesenbergia rotunda extract and its phytochemical compound, panduratin A, exhibited the potent anti-SARS-CoV-2 activity. Treatment with B. rotunda extract and panduratin A after viral infection drastically suppressed SARS-CoV-2 infectivity in Vero E6 cells with IC50 of 3.62 µg/mL (CC50 = 28.06 µg/mL) and 0.81 µΜ (CC50 = 14.71 µM), respectively. Also, the treatment of panduratin A at the pre-entry phase inhibited SARS-CoV-2 infection with IC50 of 5.30 µM (CC50 = 43.47 µM). Our study demonstrated, for the first time, that panduratin A exerts the inhibitory effect against SARS-CoV-2 infection at both pre-entry and post-infection phases. Apart from Vero E6 cells, treatment with this compound was able to suppress viral infectivity in human airway epithelial cells. This result confirmed the potential of panduratin A as the anti-SARS-CoV-2 agent in the major target cells in human. Since B. rotunda is a culinary herb generally grown in China and Southeast Asia, its extract and the purified panduratin A may serve as the promising candidates for therapeutic purposes with economic advantage during COVID-19 situation.

Cleistanthin A induces apoptosis and suppresses motility of colorectal cancer cells.

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. Here, we investigated the molecular mechanisms that underpin the anticancer effects of cleistanthin A (CA) in two CRC cell lines, HCT 116, and SW480. At 48 h, CA exhibited apoptotic cytotoxic effects in both CRC cell lines, concomitant with reduction of an anti-apoptotic protein, survivin. Mechanistically, CA treatment significantly reduced the expression levels of ß-catenin and active-ß-catenin in a dose-dependent manner in both CRC cell lines. Moreover, CA suppressed the Wnt/ß-catenin signaling pathway by decreasing ß-catenin-mediated transcriptional activity and expression of ß-catenin target genes, AXIN2, CCND1, and survivin. Furthermore, CA also inhibited transcriptional activity in cells overexpressing a constitutively active ß-catenin S33Y, indicating a GSK-3ß-independent mechanism underlying the observed CA effects on CRC cells. Although cytotoxic activity was not observed with CA treatment at 24 h, cell migration and invasion were significantly reduced. In addition, CA suppressed V-type ATPase activity and focal adhesion kinase (FAK) phosphorylation. Collectively, our study reveals that CA has time-dependent effects on CRC cell phenotypes. First, short-term CA treatment inhibited CRC cell migration and invasion partly through the suppression of V-type ATPase activity. This suppression resulted in reduced FAK activation. Second, longer-term CA treatment decreased cell viability which correlated with the suppression of Wnt/ß-catenin signaling induced transcriptional activity. Altogether, our data suggest that CA has the potential to develop as an effective and novel therapeutic drug for CRC patients.

Inhibition of topoisomerase IIα and induction of DNA damage in cholangiocarcinoma cells by altholactone and its halogenated benzoate derivatives.

Topoisomerase IIα enzyme (Topo IIα) plays a critical function in DNA replication process and is considered to be a promising target of anti-cancer drugs. In the present study, we reported that the altholactone derivatives modified by adding a halogenated benzoate group showed greater inhibitory activity on Topo IIα enzyme in cell-free system concomitant with cytotoxicity against the CCA cell lines (KKU-M055 and KKU-M213) than those of the parent altholactone. However, the cytotoxic activities of four halogenated benzoate altholactone derivatives including iodo-, fluoro-, chloro-, and bromobenzoate derivatives (compound 1, 2, 3, and 4, respectively) were of equal potency. The fluorobenzoate derivative (compound 2) was chosen for investigating the underlying mechanism in CCA cells. Compound 2 arrested CCA cell cycle at sub G1 phase and induced apoptotic cell death. It markedly inhibited Topo IIα protein expression in both KKU-M055 and KKU-M213 cells, which was accompanied by DNA double-strand breaks demonstrated by an increase in phosphorylated H2A.X protein. Interestingly, KKU-M055 cells, which express higher Topo IIα mRNA compared to KKU-M213 cells, showed greater sensitivity to the compound, indicating the selectivity of the compound to Topo IIα enzyme. By computational docking analysis, the binding affinity of altholactone (-52.5 kcal/mol) and compound 2 (-56.7 kcal/mol) were similar to that of the Topo II poison salvicine (-53.7 kcal/mol). The aromatic moiety of both altholactones embedded in a hydrophobic pocket of Topo II ATPase domain. In addition, compound 2 induced the formation of linear DNA in Topo II-mediated cleavage assay. Collectively, our results demonstrate that the addition of fluorobenzoyl group to altholactone enhances potency and selectivity to inhibit type IIα topoisomerases. Atholactone and fluorobenzoate derivative act as Topo II cleavage complexes stabilizing compounds or Topo II poisons preferentially through binding at ATPase domain of Topo IIα, leading to DNA double-strand breaks and apoptosis induction. Such activity of 3-fluorobenzoate derivative of altholactone should be further explored for the development of an anti-cancer drug for CCA.

Chrysoeriol mediates mitochondrial protection via PI3K/Akt pathway in MPP+ treated SH-SY5Y cells.

Chrysoeriol is a plant flavone extracted from the roots and leaves of the genus Phyllanthus. Although many biological properties of chrysoeriol have been reported, such as its antioxidant and anti-inflammatory activities, the effects of chrysoeriol on the cellular models of Parkinson's disease (PD) have not yet been elucidated. In the present study, we aimed to investigate whether chrysoeriol prevents neurotoxicity induced by 1-methyl-4-phenylpyridinium iodide (MPP+) in SH-SY5Y cells, a typical in vitro PD model. The cell viability was measured by MTT assay. The morphological changes of apoptotic cell nuclei were observed by Hoechst 33,342 staining. The expression of Bax, Bcl-2 and Caspase-3 were detected by western blot analysis. The mitochondria location in the cells was observed by Mitotracker staining. Mitochondrial membrane potential was evaluated by the JC-10 assay. Treatment with MPP+ significantly caused a decrease in the viability of cells and an increase in apoptosis, as evidenced by the upregulation of apoptotic cells, caspase-3 activity and antiapoptotic ratio. These effects were all reversed by pretreatment with chrysoeriol in SH-SY5Y cells. Moreover, pretreatment with chrysoeriol markedly mitigated the MPP+-caused increases in the levels of the prosurvial signaling proteins, phosphorylated Akt and phosphorylated mTOR. The presence of a specific PI3K inhibitor, wortmannin, particularly abolished the chrysoeriol-induced activation of Akt phosphorylation and prevented the chrysoeriol-induced survival effect. These results indicate that the neuroprotective effect of chrysoeriol against MPP+ treatment requires the activation of PI3K/Akt pathway. Ultimately, chrysoeriol could be a promising therapeutic agent for the further experiment on the treatment of PD.

Anti-HIV-1 activities of constituents from the rhizomes of Boesenbergia thorelii.

A new lignan, thoreliin A (1), and a new bisnorlignan, thoreliin B (2), were isolated from a MeOH extract of the rhizomes of Boesenbergia thorelii. In addition, the known bisnorlignans 3 and 4, neolignan 5, phenylpropanoids 6-15, as well as benzenoids 18-21 were also obtained from the same source. The structures were elucidated based on their spectroscopic data. By single crystal X-ray analysis, the relative stereochemistry of 1 was confirmed. All isolated compounds were evaluated for anti-HIV-1 activities. Among them, thoreliin A (1) exhibited anti-HIV-1 activities on both HIV-1 reverse transcriptase (41.43% inhibition at 200 µg/mL) and syncytium reduction assays (EC50 20.6 µM, SI 3.7), while compounds 3-6, 9 and 11-21 showed anti-HIV-1 activity only in the anti-syncytium assay (EC50 6.6-454.1 µM, SI >1.32-7.75).

A novel potent autophagy inhibitor ECDD-S27 targets vacuolar ATPase and inhibits cancer cell survival.

Autophagy is a conserved lysosomal-dependent cellular degradation process and its dysregulation has been linked to numerous diseases including neurodegeneration, infectious diseases, and cancer. Modulation of autophagy is therefore considered as an attractive target for disease intervention. We carried out a high-content image analysis screen of natural product-derived compounds to discover novel autophagy modulating molecules. Our screen identified ECDD-S27 as the most effective compound for increasing the number of autophagic vacuoles inside cells. The structure of ECDD-S27 revealed that it is a derivative of cleistanthin A, a natural arylnaphthalene lignan glycoside found in plants. ECDD-S27 increases the number of autophagic vacuoles by inhibiting the autophagic flux and is able to restrict the survival of different cancer cells at low nanomolar concentrations. Molecular docking and SERS analysis showed that ECDD-S27 may potentially target the V-ATPase. Upon treatment of various cancer cells with ECDD-S27, the V-ATPase activity is potently inhibited thereby resulting in the loss of lysosomal acidification. Taken together, these data indicated that ECDD-S27 retards the autophagy pathway by targeting the V-ATPase and inhibits cancer cell survival. The observed antitumor activity without cytotoxicity to normal cells suggests the therapeutic potential warranting further studies on lead optimization of the compound for cancer treatment.

Phyllanthus taxodiifolius Beille suppresses microtubule dynamics and restricts glioblastoma aggressiveness.

Glioblastoma is the most common and the most malignant form of brain tumor. This devastating tumor results in death within a year after diagnosis. Although the tumor mass can be surgically removed, glioma cells invade other areas in the brain leading to tumor recurrence and poor prognosis. Therefore, new agents that can overcome cancer cell invasion are urgently required. Phyllanthus taxodiifolius Beille (P. taxodiifolius), has been reported to have potent anti-cancer activities. However, its effects on glioblastoma cells and its underlying mechanisms have never been revealed. Here we investigated the effect and underlying mechanisms of P. taxodiifolius extract on aggressive properties of the glioblastoma, including adhesion, migration, and invasion. P. taxodiifolius extract disrupted adhesion, delayed migration and interfered with the invasion of glioblastoma cells. In addition, the extract suppressed microtubule dynamics as shown by live imaging of a microtubule plus tip protein and decreased focal adhesion by decreasing focal adhesion kinase activity. Our study is the first evidence showing that P. taxodiifolius extract suppresses invasive properties of glioblastoma cells by disrupting microtubule structure and interfering with microtubule dynamics, suggesting the possibility to further develop P. taxodiifolius and its bioactive compounds as an anti-cancer drug targeting microtubules in glioblastoma.

Development of pure certified reference material of stevioside.

Pure stevioside was extracted from leaves of Stevia rebaudiana (Bertoni) to be used as a reference material in the instrument calibration or method validation process. The mass fraction was determined by comparison between the mass balance method and quantitative nuclear magnetic resonance (qNMR) spectroscopy. The impurities in the sample were analyzed by Karl Fischer titration for moisture content and thermogravimetric analysis for inorganic residue. Homogeneity, together with short term and long term stability, were also studied and the uncertainty was reported. The certified value of this mass fraction is 0.986 ±â€¯0.0019 (k = 2) with 1 year stability.

Anti-HIV and cytotoxic biphenyls, benzophenones and xanthones from stems, leaves and twigs of Garcinia speciosa.

Eleven previously undescribed compounds, including four benzophenones (garciosones A-D), four xanthones (garciosones E-H) and three biphenyls (garciosines A-C), along with eighteen known compounds were isolated from the stems, leaves and twigs of Garcinia speciosa Wall. (Clusiaceae). Their structures were established by extensive spectroscopic analysis. For garciosines A-C, the structures were confirmed by single crystal X-ray diffraction analysis. Most of the isolated compounds were evaluated for their cytotoxic activity and anti-HIV-1 activity using the syncytium inhibition assay and HIV-1 reverse transcriptase (RT) assay. The known compounds, 4,6,3',4'-tetrahydroxy-2-methoxybenzophenone and macluraxanthone, displayed significant cytotoxic activity with the ED50 in the range of 1.85-11.76 µM. 1,5-Dihydroxyxanthone exhibited the most potent anti-HIV activity against syncytium formation with EC50 < 17.13 µM (SI > 25.28) and 2-(3,3-dimethylallyl)-1,3,7-trihydroxyxanthone was the most active compound in the HIV-1 reverse transcriptase assay with IC50 value of 58.24 µM. Structure-activity relationship of some isolated compounds were also discussed.

Curcuma comosa reduces visceral adipose tissue and improves dyslipidemia in ovariectomized rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Curcuma comosa Roxb. (C. comosa) or Wan chak motluk Zingiberaceae family, is widely used in Thai traditional medicine for treatment of gynecological problems as well as relief of postmenopausal symptoms. Since C. comosa contains phytoestrogen and causes lipid lowering effect by an unknown mechanism, we investigated its effect on adiposity and lipid metabolism in estrogen-deprived rats. MATERIALS AND METHODS: Adult female rats were ovariectomized (OVX) and received daily doses of either a phytoestrogen from C. comosa [(3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol; DPHD], C. comosa extract, or estrogen (17ß-estradiol; E2) for 12 weeks. Adipose tissue mass, serum levels of lipids and adipokines were determined. In addition, genes and proteins involved in lipid synthesis and fatty acid oxidation in visceral adipose tissue were analyzed. RESULTS: Ovariectomy for 12 weeks elevated level of serum lipids and increased visceral fat mass and adipocyte size. These alterations were accompanied with the up-regulation of lipogenic mRNA and protein expressions including LXR-α, SREBP1c and their downstream targets. OVX rats showed decrease in proteins involved in fatty acid oxidation including AMPK-α and PPAR-α in adipose tissue, as well as alteration of adipokines; leptin and adiponectin. Treatments with E2, DPHD or C. comosa extract in OVX rats prevented an increase in adiposity, down-regulated lipogenic genes and proteins with marked increases in the protein levels of AMPK-α and PPAR-α. These findings indicated that their lipid lowering effects were mediated via the suppression of lipid synthesis in concert with an increase in fatty acid oxidation. CONCLUSIONS: C. comosa exerts a lipid lowering effect in the estrogen deficient rats through the modulations of lipid synthesis and AMPK-α activity in adipose tissues, supporting the use of this plant for health promotion in the post-menopausal women.