Carlinoside reduces hepatic bilirubin accumulation by stimulating bilirubin-UGT activity through Nrf2 gene expression

Accu mulati on of biliru bin, prima rily because of its insol ubilit y, has bee n found to be associa ted with liver disea ses includ ing jaundice . Free bilir ubin is insol uble; its glucuro nidation by bilirubin -UGT enz yme (UGT1 A1) makes it soluble and elimina tes it throu gh urine and fae ces. Taki ng CCl 4 induced ra t liver dysfun ction m odel, we demonst rated that supp ression of UGT1A 1 activity in ra t liv er increa sed ser um biliru bin level wh ich could be reve rsed by carl inoside (Cln), a flavone glyc oside. Alth ough Cln is a flavone compou nd, it escaped self-glucu ronid ation in the intestin e and readily absorbe d. Kineti c stud y of mic rosoma l UGT1A 1 from HepG 2 cells sugg ested that Cln enhan ced enz yme activity by increa sing V max with out alterin g K m. This altered V max was foun d to be due to UGT1A 1 ove rexpre ssion by Cln wh ich wa s obser ved in both HepG 2 and rat prima ry hepa tocytes . Sin ce Nrf2 is the transc ription factor of UG T1A1, we exam ined whethe r Cln effe ct on UG T1A1 overexp ression is media ted th rough Nrf2. In Nrf2 knock -out cells, Cln cou ld not eleva te UG T1A1 activity indica ting Nrf2 to be its target. Cln signific antly increas ed Nrf2 ge ne expr ession in HepG2 cells wh ich was subse quently locali zed in nuclear region . Resu lts from Ch IP assa y show ed that Cln mar kedly augm ented Nrf2 bindi ng to UGT1A 1 prom oter that con sequentl y enhan ced report er act ivity. Our findings therefor e show that Cln upreg ulated Nr f2 gene expr ession, incr eased its nu clear tran slocation and stimula ted UGT1A 1 prom oter act ivity. Tota l outc ome of these even ts brought about a signific ant increase of biliru bin glucur onida tion. Cln ther efore could be a wor thy choice to int ervene hype rbilir ubinemi a due to liv er dysfunc tion

Core-shell hybrid nanoparticles with functionalized Quantum dots and ionic dyes: growth, monolayer formation, and electrical bistability

We report growth, monolayer formation, and (electrical bistability and memory phenomenon) properties of hybrid core-shell nanoparticles. While inorganic quantum dots, such as CdS or CdSe, act as the core, a monolayer of ionic organic dye molecules, electrostatically bound to the surface of functionalized quantum dots, forms the shell. We form a monolayer of the core-shell hybrid nanoparticles via a layer-by-layer electrostatic assembly process. Growth and monolayer formation of the organic-inorganic hybrid nanoparticles have been substantiated by usual characterization methods, including electronic absorption spectroscopy of dispersed solution and atomic force microscope images of scratched films. Devices based on the hybrid nanoparticles have exhibited electrical bistability and memory phenomena. From the comparison of these properties in core-shell nanoparticles and in its components, we infer that the degree of conductance switching or on/off ratio is substantially higher in the hybrid nanoparticles. Also, they (core-shell particles) provide routes to tune the bistability and memory phenomena by choosing either of the components. A monolayer of hybrid nanoparticles has been characterized by a scanning tunneling microscope tip as the other electrode. We show that a single core-shell hybrid nanoparticle can exhibit bistability with an associated memory phenomenon. Charge confinement, as evidenced by an increase in the density of states, has been found to be the mechanism of electrical bistability

Enhancement of electrical bistability through semiconducting nanoparticles for organic memory applications

We report that an enhancement in electrical bistability in devices based on organic molecules can be achieved by the introduction of semiconducting nanoparticles. Here, devices based on alternate layers of a dye in the xanthene class and CdSe nanoparticles have been compared with devices based on the individual components. Results from dye/CdSe devices have yielded an appreciable enhancement in electrical bistability compared with those based on the dye or the nanoparticles. The enhancement is due to augmented carrier transport through the nanoparticles to the dye that consequently undergoes a change in its conformation, having a higher conductivity. We have evidenced read-only and random-access memory applications in the dye/nanoparticle hybrid system

First Indium Trichloride Catalyzed Self-Addition of Indoles: One Pot Synthesis of Indolylindolines

Indole (1), 5-methoxyindole (1c) and their N-substituted derivatives undergo self-addition to afford indolylindoline derivatives 2a–e and trimers 4a–e in fairly good yield in the presence of catalytic amount (20 mol%) of anhyd indium trichloride.

Glucosides from Curculigo orchioides

From the rhizomes of Curculigo orchioides two phenolic glucosides named orchiosides A and B were isolated besides four known compounds and their structures were elucidated by the combination of 2D-NMR analysis, mass spectrometry and chemical evidences. � 2004 Elsevier Ltd. All rights reserved

A Triterpenoid Glucoside from Barrlngtonia Acutangula

The structure of a new triterpenoid glucoside from Bnrringtonia acutangula was deduced as 2&3fi,19atrihydroxy- olean-12ene-23,28-dioic acid 28-O-fi-D-glucopyranoside from chemical reactions and spectral data

Transport gap of nanoparticle-passivated silicon substrates

The transport gap of nanoparticle-passivated Si substrates is measured by scanning tunneling microscopy. Passivation is achieved using a monolayer of CdSe nanoparticles. It is shown that the transport gap and conduction-band edge of the system change upon passivation. The size of the nanoparticles that passivate the Si substrate is varied to study its effect on the transport gap of the system. Plots of the tunneling current versus voltage show that the transport gap of the system can be tuned by the binding of just a monolayer of suitable nanoparticles. From the normalized density of states, it is shown that the conduction-band edge of the system responds to the size of the nanoparticles. Here, a monolayer of the nanoparticles, which were capped with suitable functional groups, has been formed via electrostatic adsorption with the substrate

Evaluation of Spermicidal Activity of Mi-Saponin A

The seed extracts of Madhuca latifolia were reported to have spermicidal activity. The current investigation identified the spermicidal component of the extracts and evaluated its spermicidal potential in vitro. As characterized by infrared, mass, and nuclear magnetic resonance (NMR) spectral analyses,Mi-saponin A (MSA) was found to be the most potent component among a mixture of saponins. The mean effective concentrations of MSA that induced irreversible immobilization were 320 mg/mL for rat and 500 mg/mL for human sperm, as against the respective concentrations of 350 and 550 mg/mL of nonoxynol 9 (N-9). The mode of spermicidal action was evaluated by a battery of tests including (a) double fluoroprobe staining for spermviability, (b) hypoosmotic swelling test and, assays for 5’ nucleotidase and acrosin for physiological integrity of sperm plasmamembrane, (c) scanning and transmission electron microscopy for sperm membrane ultrastructure, and (d) plasma membrane lipid peroxidation (LPO). The observations, taken together,were interpreted to mean that the spermicidal effect ofMSAinvolved increased membraneLPOleading to structural and functional disintegration of spermplasmamembrane and acrosomal vesicle.Acomparative in vitro cytotoxicity study in human vaginal keratocyte (Vk2/E6E7) and endocervical (End/E6E7) cell lines demonstrated that the 50% cell cytotoxicity (CC50) values, and consequently the safety indices, for MSA were� 8-fold higher as compared to those ofN-9. In conclusion,MSA is a potent spermicidal molecule that may be explored further for its suitability as an effective component of vaginal contraceptive

Structure of Acaciaside, a Triterpenoid Trisaccharide from Acacia Aurzculiformis

structure of a new triterpenoid trisaccharide isolated from the seeds of Acacia auriculiformis has been elucidated as acacic acid lactone-3-O-/?-D-glucopyranosyl (1 -+6)-[a-L-arabinopyranosyl (l-+2)]-p-D-glucopyranoside based on its spectral properties and some chemical transformations

Hopane-type saponins from Glinus lotoides Linn

Seven hopane-type saponins were isolated from the methanol extract of Glinus lotoides. Six of them were identified as novel compounds and designated as lotoideside A [3-O-b-D-xylopyranosyl (1! 2)-a-L-rhamnopyranosyl-6a-O-b-D-xylopyranosyl-22-b-O-b-Dglucopyranosyl- 16b-hydroxy hopane (1)], lotoideside B [3-O-b-D-xylopyranosyl (1 !2)-a-L-rhamnopyranosyl-22-b-O-b-D-glucopyranosyl- 6a,16b-dihydroxyhopane (2)], lotoideside C [3-OD-xylopyranosyl-6a-O-b-D-xylopyranosyl-16b-O-b-D-xylopyranosyl-22bhydroxyhopane (3)], lotoideside D [3-O-b-D-xylopyranosyl-16b-O-a-L-arabinopyranosyl-6a,22-b-dihydroxyhopane (4)], lotoideside E [3-O-b-D-xylopyranosyl-6a-O-b-D-xylopyranosyl-16 b,22-b-dihydroxyhopane (5)], and lotoideside F [3-O-b-D-xylopyranosyl-22- b-O-b-D-glucopyranosyl-16b-hydroxyhopan-6-one (6)]. The known compound succulentoside B (7) was also encountered. Their structures were elucidated on the basis of one-and two-dimensional NMR spectroscopic techniques, ESIMS and chemical evidences. � 2005 Elsevier Ltd. All rights reserved