Purification of triterpenoid saponins and 25R/25S-inokosterone from Achyranthes bidentata Bl. by high-speed countercurrent chromatography coupled silver nitrate coordination.

An effective method by high-speed countercurrent chromatography coordinated with silver nitrate for the preparative separation of sterones and triterpenoid saponins from Achyranthes bidentata Blume was developed. Methyl tert-butyl ether/n-butanol/acetonitrile/water (4:2:3:8, v/v/v/v) was selected for 20-hydroxyecdysone (compound 1), chikusetsusaponin IVa methyl ester (compound 4), 2'-glycan-11-keto-pigmented saponin V (compound 5), as well as a pair of isomers of 25S-inokosterone (compound 2) and 25R-inokosterone (compound 3), which were further purified by silver nitrate coordinated high-speed countercurrent chromatography. What is more, dichloromethane/methanol/isopropanol/water (6:6:1:4, v/v/v/v) was applied for calenduloside E (compound 6), 3ß-[(O-ß-d-glucuronopyranosyl)-oxy]-oleana-11,13-dien-28-oic acid (compound 7), zingibroside R1 (compound 8) and chikusetsusaponin IVa (compound 9). Adding Ag+ to the solvent system resulted in unique selectivity for 25R/25S isomers of inokosterone, which increased the complexing capability and stability of Ag+ coordinated 25S-inokosterone, as well as the α value between them. These results were further confirmed by the computational calculation of geometry optimization and frontier molecular orbitals assay. Comprehensive mass spectrometry and nuclear magnetic resonance analysis demonstrated the structures of the obtained compounds.

A network pharmacology-based strategy to explore the pharmacological mechanisms of Antrodia camphorata and antcin K for treating type II diabetes mellitus.

BACKGROUND: Diabetes mellitus is a chronic carbohydrate metabolism disorder, which could develop a series of complications and thus lead to poor quality of life or even mortality. Antrodia camphorata is a rare parasitic fungus and has been proven to be effective for treating type II diabetes. PURPOSE: This study aims to evaluate the anti-diabetic activities of A. camphorata and its main compound antcin K, as well as to demonstrate the mechanisms. STUDY DESIGN AND METHODS: Network pharmacology was used to explore the potential targets of 12 major compounds of A. camphorata on diabetes. The core targets were analyzed by protein-protein interactions and the key pathways were enriched by Kyoto Encyclopedia of Genes and Genomes (KEGG). The anti-diabetic effects of A. camphorata and antcin K were evaluated using a high-fat diet (HFD)-induced diabetic mice model and oral glucose tolerance test (OGTT). The mRNA expressions were assessed using qPCR. RESULTS: Network pharmacology revealed 17 core targets between the 12 compounds and diabetes. The insulin resistance and NF-κB signaling pathways were enriched using KEGG. Five insulin resistance-related targets were focused on and antcin K (1/2) was discovered in the compound-target-pathway network. In vivo studies exhibited that A. camphorata and antcin K could dose-dependently reduce blood levels of glucose and lipids, decrease serum levels of insulin and leptin, and increase serum levels of adiponectin in HFD mice (p < 0.05). The mechanism could be through modulating the expressions of Tnfα, Il6, and Pparγ. The OGTT test also showed the down-regulatory effects of A. camphorata and antcin K on blood glucose. CONCLUSION: This study demonstrates that A. camphorata and its major compound antcin K possess potent anti-diabetic effects. The mechanism may be through the insulin resistance pathway.

Inokosterone Is A Potential Drug Target of Estrogen Receptor 1 in Rheumatoid Arthritis Patients: Analysis from Active Ingredient of Cyathula Officinalis.

OBJECTIVE: To elucidate the active compounds and the molecular mechanism of Cyathula Officinalis as a drug treatment for rheumatoid arthritis (RA). METHODS: The target genes of active ingredients from Cyathula Officinalis were obtained from bioinformatics analysis tool for the molecular mechanism of traditional Chinese medicine. The protein-protein interaction between the target genes were analyzed using STRING and Genemania. The transcriptome of RA patients compared to healthy people (GSE121894) were analyzed using R program package Limma. The relative expression of the target genes was obtained from the RNA-seq datasets. The molecular docking analyses were processed based on the molecular model of estrogen receptor 1 (ESR1) binding with estradiol (PDB ID:1A52). The binding details were analyzed by SYBYL. RESULTS: Inokosterone, ecdysterone, and cyaterone were the 3 active ingredients from Cyathula Officinalis that bind to target genes. Of all the significantly changed genes from RA patients, ESR1, ADORA1, and ANXA1 were significantly increased in mRNA samples of RA patients. CONCLUSION: ESR1, the transcription factor that binds inokosterone in the molecular binding analysis, is the target protein of Cyathula Officinalis.

Antcin K Inhibits TNF-α, IL-1ß and IL-8 Expression in Synovial Fibroblasts and Ameliorates Cartilage Degradation: Implications for the Treatment of Rheumatoid Arthritis.

Extracts from Taiwan's traditional medicinal mushroom, Antrodia cinnamomea, exhibit anti-inflammatory activities in cellular and preclinical studies. However, this paper is the first to report that Antcin K, a triterpenoid isolated from A. cinnamomea, inhibits proinflammatory cytokine production in human rheumatoid synovial fibroblasts (RASFs), which are major players in rheumatoid arthritis (RA) disease. In our analysis of the mechanism of action, Antcin K inhibited the expression of three cytokines (tumor necrosis factor alpha [TNF-α], interleukin 1 beta [IL-1ß] and IL-8) in human RASFs; cytokines that are crucial to RA synovial inflammation. Notably, incubation of RASFs with Antcin K reduced the phosphorylation of the focal adhesion kinase (FAK), phosphoinositide 3-kinase (PI3K), protein kinase B (AKT) and nuclear factor-κB (NF-κB) signaling cascades, all of which promote cytokine production in RA. Intraperitoneal injections of Antcin K (10 mg/kg or 30 mg/kg) attenuated paw swelling, cartilage degradation and bone erosion, and decreased serum levels of TNF-α, IL-1ß, IL-8 in collagen-induced arthritis (CIA) mice; in further experiments, IL-6 levels were similarly reduced. The inhibitory effects of Antcin K upon TNF-α, IL-1ß and IL-8 expression in human RASFs was achieved through the downregulation of the FAK, PI3K, AKT and NF-κB signaling cascades. Our data support clinical investigations using Antcin K in RA disease.

Inokosterone Is A Potential Drug Target of Estrogen Receptor 1 in Rheumatoid Arthritis Patients: Analysis from Active Ingredient of Cyathula Officinalis / 中国结合医学杂志

OBJECTIVE@#To elucidate the active compounds and the molecular mechanism of Cyathula Officinalis as a drug treatment for rheumatoid arthritis (RA).@*METHODS@#The target genes of active ingredients from Cyathula Officinalis were obtained from bioinformatics analysis tool for the molecular mechanism of traditional Chinese medicine. The protein-protein interaction between the target genes were analyzed using STRING and Genemania. The transcriptome of RA patients compared to healthy people (GSE121894) were analyzed using R program package Limma. The relative expression of the target genes was obtained from the RNA-seq datasets. The molecular docking analyses were processed based on the molecular model of estrogen receptor 1 (ESR1) binding with estradiol (PDB ID:1A52). The binding details were analyzed by SYBYL.@*RESULTS@#Inokosterone, ecdysterone, and cyaterone were the 3 active ingredients from Cyathula Officinalis that bind to target genes. Of all the significantly changed genes from RA patients, ESR1, ADORA1, and ANXA1 were significantly increased in mRNA samples of RA patients.@*CONCLUSION@#ESR1, the transcription factor that binds inokosterone in the molecular binding analysis, is the target protein of Cyathula Officinalis.

Lophenol and lathosterol from resin of Commiphora kua possess hepatoprotective effects in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Drug induced liver damage remains a prevalent concern in healthcare and may reduce the effectiveness of therapy by compromising therapeutic regimens. Many Commiphora species are known for their medicinal properties, and some of them are used traditionally for hepatoprotective effect. In the course of our drugs discovery from natural sources, phytosterols (lophenol (Lop) and lathosterol (Lat)), isolated from Commiphora kua were studied to evaluate their hepatoprotective effects in acetaminophen (APAP) induced hepatotoxicity in mice. AIMS AND OBJECTIVE: To evaluate the hepatoprotective effects of phytosterols isolated from C. kua using in vivo experimental model. MATERIALS AND METHODS: Mice of either sex were divided into 7 groups: Vehicle, silymarin (SLY), acetaminophen (APAP), Lop 25, Lop 50, Lat 25, Lat 50 (n = 5). Vehicle group received only vehicle (0.1% DMSO solution) for 7 days, APAP group received single dose of acetaminophen on day 7 and SLY group received silymarin for 7 days. Lop 25 and Lop 50 received low and high doses of Lop (25 µg/kg BW and 50 µg/kg BW), respectively, for 7 days, while Lat 25 and Lat 50 received low and high doses of Lat (25 µg/kg BW and 50 µg/kg BW) for 7 days. On day 7, all animals except Vehicle group kept fasted for 18 h and received APAP i. p. 400 mg/kg BW. After 20 h of APAP administration, the animals anesthetized with light chloroform and scarified by cervical decapitation. The blood serum and liver tissue samples were collected for biochemical and histopathological analysis. Liver function tests (LFTs) including lactate deydrogenase (LDH), alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST) and direct bilirubin) were used as biochemical parameters. While catalase (CAT), superoxide dismutase (SOD) and reduced glutathione (GSH) were taken as anti-oxidant enzymes. RESULTS: Significant increase in levels of ALT, AST, ALP, LDH and direct bilirubin, and significant decrease in concentration of anti-oxidant enzymes (SOD, CAT and GSH) was observed in APAP-treated group. Similarly, histological slides showed obvious signs of damage to liver cells, reflecting acetaminophen induced hepatotoxicity. Treatment of test animals with phytosterols resulted in significant recovery of LFTs profile and concentration of anti-oxidant enzymes. Similarly, significant improvement of liver tissues was noted in histological analysis. CONCLUSIONS: Both phytosterols possessed hepatoprotective potential and should be further evaluated for acute toxicity studies and pharmacokinetics/pharmacodynamics profile.

Secondary metabolites of petri-dish cultured Antrodia camphorata and their hepatoprotective activities against alcohol-induced liver injury in mice.

Antrodia camphorata, a well-known and highly valued edible medicinal mushroom with intriguing activities like liver protection, has been traditionally used for the treatment of alcoholic liver disease. A. camphorata shows highly medicinal and commercial values with the demand far exceeds the available supply. Thus, the petri-dish cultured A. camphorata (PDCA) is expected to develope as a substitute. In this paper, nineteen triterpenes were isolated from PDCA, and thirteen of them were the unique anthroic acids in A. camphorata, including the main content antcin K, which suggested that PDCA produced a large array of the same anthroic acids as the wild one. Furthermore, no obvious acute toxicity was found suggesting the edible safety of PDCA. In mice alcohol-induced liver injury model, triglyceride (TG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA) had been reduced by the PDCA powder as well as the main content antcin K, which indicated that the PDCA could protect alcoholic liver injury in mice model and antcin K could be the effective component responsible for the hepatoprotective activities of PDCA against alcoholic liver diseases.

Antcins, triterpenoids from Antrodia cinnamomea, as new agonists for peroxisome proliferator-activated receptor α.

Peroxisome proliferator-activated receptor α (PPARα) is a nuclear hormone receptor that transcriptionally regulates lipid metabolism and inflammation; therefore, PPARα agonists are promising agents to treat dyslipidemia and metabolic disorders. PPARα full agonists, such as fibrates, are effective anti-hypertriglyceride agents, but their use is limited by adverse side effects. Hence, the aim of this study was to identify small molecules that can activate PPARα while minimizing the adverse effects. Antrodia cinnamomea, a rare medical mushroom, has been used widely in Asian countries for the treatment of various diseases, including liver diseases. Antcin B, H and K (antcins) and ergostatrien-3ß-ol (EK100) are bioactive compounds isolated from A. cinnamomea with anti-inflammatory actions. Antcins, ergostane-type triterpenoids, contain the polar head with carboxylate group and the sterol-based body. Here, we showed at the first time that sterol-based compounds, antcins, but not EK100, activate PPARα in a cell-based transactivation study. The in silico docking studies presented several significant molecular interactions of antcins, including Tyr314, and His440 in the ligand-binding domain of PPARα, and these interactions are required for helix 12 (H12) stabilization. We propose that PPARα activation activity of antcins is related to their binding mode which requires conventional H12 stabilization, and that antcins can be developed as safe selective PPARα modulators.

[Determination of three anthroic acids in petri dish cultured Antrodia camphorate by quantitative analysis of multi-component with single marker].

The present study is establish the quantitative analysis of multi-component with single marker for determining three anthroic acids, (25S)-antcin K, (25R)-antcin K and (25S)-antcin C in the petri dish cultured Antrodia camphorata. The relative correction factors of (25S)-antcin K and (25R)-antcin K were established by high performance liquid chromatography with (25S)-antcin C as the internal reference. Relative correction factors were used to calculate the contents of (25S)-antcin K and (25R)-antcin K which were difficult to gain in abundance. At the same time, the contents of these three compounds were determined by external standard method. Two methods were compared to evaluate the accuracy and rationality of the multi-components with single marker method in the determination of the petri dish cultured A. camphorate. It was found that the quantitative method of multi-component with single marker and external standard method showed no significant difference. In summary, taking (25S)-antcin C as the internal reference, the method of multi-component with single marker can be applied to the quantitative analysis of (25S)-antcin K and (25R)-antcin K in the petri dish cultured A. camphorata.

Fruiting Bodies of Antrodia cinnamomea and Its Active Triterpenoid, Antcin K, Ameliorates N-Nitrosodiethylamine-Induced Hepatic Inflammation, Fibrosis and Carcinogenesis in Rats.

Antrodia cinnamomea (A. cinnamomea), a popular medicinal mushroom in Taiwan, is widely used to prevent or treat liver diseases. Systematic studies on the anti-inflammatory effect of A. cinnamomea and its molecular mechanisms have not yet been fully investigated. HPLC fingerprint analysis identified seven ergostane-type triterpenoids from A. cinnamomea water extract (ACW), including high amounts of Antcin K (AC), Antcin C, Antcin H, Dehydrosulphurenic acid, Antcin B, Antcin A and Dehydroeburicoic acid. Here, we explored the effects and mechanisms of ACW and the highest content AC on N-nitrosodiethylamine (DEN) induced liver inflammation, fibrosis and carcinogenesis in rats. In the in vitro study, we measured how ACW and AC dose-dependently scavenged O[Formula: see text], H2O2 and HOCl by a chemiluminescence analyzer. In the in vivo experiment, oral intake ACW and AC significantly inhibited DEN-enhanced hepatocellular inflammation, fibrosis and carcinoma by pathologic observation, the elevated bile and liver reactive oxygen species (ROS) amounts, plasma [Formula: see text]-glutamyl transpeptidase, and oxidative stress including 3-nitrotyrosine, 4-hydroxynonenal and Kuppfer cell infiltration (ED-1 stains) in the inflammatory livers. DEN enhanced nuclear factor-[Formula: see text]B (NF-[Formula: see text]B) translocation, whereas ACW and AC suppressed DEN-enhanced NF-[Formula: see text]B translocation through the inhibition of its upstream signaling of p85/phosphoinositide-3-kinase, mitogen activated protein kinase and CYP2E1 expression. In conclusion, DEN can induce hepatocellular inflammation, fibrosis and carcinoma by increasing NF-[Formula: see text]B translocation to the nucleus, and oxidative injury. ACW and its active component, Antcin K, counteract DEN-induced hepatic injury and inflammation by the protective and therapeutic mechanisms of a direct scavenging ROS activity and an upregulation of anti-oxidant defense mechanisms.

Antcin H Protects Against Acute Liver Injury Through Disruption of the Interaction of c-Jun-N-Terminal Kinase with Mitochondria.

AIM: Antrodia Camphorate (AC) is a mushroom that is widely used in Asian countries to prevent and treat various diseases, including liver diseases. However, the active ingredients that contribute to the biological functions remain elusive. The purpose of the present study is to test the hepatoprotective effect of Antcin H, a major triterpenoid chemical isolated from AC, in murine models of acute liver injury. RESULTS: We found that Antcin H pretreatment protected against liver injury in both acetaminophen (APAP) and galactosamine/tumor necrosis factor (TNF)α models. More importantly, Antcin H also offered a significant protection against acetaminophen-induced liver injury when it was given 1 h after acetaminophen. The protection was verified in primary mouse hepatocytes. Antcin H prevented sustained c-Jun-N-terminal kinase (JNK) activation in both models. We excluded an effect of Antcin H on acetaminophen metabolism and TNF receptor signaling and excluded a direct effect as a free radical scavenger or JNK inhibitor. Since the sustained JNK activation through its interaction with mitochondrial Sab, leading to increased mitochondrial reactive oxygen species (ROS), is pivotal in both models, we examined the effect of Antcin H on p-JNK binding to mitochondria and impairment of mitochondrial respiration. Antcin H inhibited the direct effect of p-JNK on isolated mitochondrial function and binding to isolated mitochondria. Innovation and Conclusion: Our study has identified Antcin H as a novel active ingredient that contributes to the hepatoprotective effect of AC, and Antcin H protects against liver injury through disruption of the binding of p-JNK to Sab, which interferes with the ROS-dependent self-sustaining activation of MAPK cascade. Antioxid. Redox Signal. 26, 207-220.

Bis-sesquiterpene from the Marine Sponge Dysidea fragilis.

Two new sesquiterpenes and one new bis-sesquiterpene, named dysinidins C-E (1-3) along with three known sterols, dysideasterol F, 9α,l lα-epoxycholest-7-en-3ß,5α,6α-triol, and 9α,11α-epoxycholest-7-en-3ß,5α,6α,19-tetrol 6-acetate (4-6) were isolated from the Vietnamese marine sponge Dysidea fragilis (Montagu, 1814). Their structures were determined by 1D- and 2D-NMR spectroscopies and HR-ESI-MS, as well as by comparison with reported literature data. Compounds 4-6 were found to inhibit eight human cancer cell lines (KB, LU-1, HL-60, LNCaP, SK-Mel-2, HepG-2, MCF-7, and PC-3), with IC50 values ranging from 7.3 to 31.5 µM.

Identification of candidate synovial membrane biomarkers after Achyranthes aspera treatment for rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic autoimmune disease whose main symptom is a heightened inflammatory response in synovial tissues. To verify the anti-arthritic activities of Achyranthes aspera and its possible therapy-related factors on the pathogenesis of RA, the saponins in A. aspera root were isolated and identified to treat the collagen-induced arthritis (CIA) rats. Phytochemical analysis isolated and identified methyl caffeate, 25-S-inokosterone, 25-S-inokosterone ß-D-glucopyranosyl 3-(O-ß-D-glucopyranosyloxy)-oleanolate, and ß-D-glucopyranosyl 3-(O-ß-D-galactopyranosyl (1→2)(O-ß-D-glucopyranosyloxy)-oleanolate as main compounds in the root of A. aspera. Proteomics was performed to determine the differentially expressed proteins in either inflamed or drug-treated synovium of CIA rats. Treatment resulted in dramatically decreased paw swelling, proliferation of inflammatory cells, and bone degradation. Fibrinogen, procollagen, protein disulfide-isomerase A3, and apolipoprotein A-I were all increased in inflamed synovial tissues and were found to decrease when administered drug therapy. Furthermore, Alpha-1-antiproteinase and manganese superoxide dismutase were both increased in drug-treated synovial tissues. The inhibition of RA progression shows that A. aspera is a promising candidate for future treatment of human arthritis. Importantly, the total saponins found within A. aspera are the active component. Finally, autoantigens such as fibrinogen and collagen could act as inducers of RA due to their aggravation of inflammation. Given this, it is possible that the vimentin and PDIA3 could be the candidate biomarkers specific to Achyranthes saponin therapy for rheumatoid arthritis in synovial membrane.

A new alkaloid from the fruit of Nandina domestica Thunb.

A new steroidal alkaloid, (20S,22R,24R)-24-ethyl-3-oxocholest-4-en-22-amino, named as nandsterine (1), together with 10 known alkaloids, palmatine (2), O-methylbulbocapnine (3), nantenine (4), dehydronantenine (5), glaucine (6), didehydroglaucine (7), dehydrocorydaline (8), jatrorrhizine (9), magnoflorine (10) and berberine (11), was isolated from the fruit of Nandina domestica Thunb. Their structures were elucidated by using spectroscopic methods as well as by comparing with the published data. Compound 1 was a new class of steroidal alkaloid isolated from the family Berberidaceae, meanwhile compounds 2, 3, 6-8 and 10 were obtained from N. domestica for the first time. Compound 1 exhibited cytotoxicity against HL-60 cells (human leukaemia) with IC50 values of 52.1 µM.

Enzymatic hydrolysis of steryl glucosides, major contaminants of vegetable oil-derived biodiesel.

Biodiesels are mostly produced from lipid transesterification of vegetable oils, including those from soybean, jatropha, palm, rapeseed, sunflower, and others. Unfortunately, transesterification of oil produces various unwanted side products, including steryl glucosides (SG), which precipitate and need to be removed to avoid clogging of filters and engine failures. So far, efficient and cost-effective methods to remove SGs from biodiesel are not available. Here we describe for the first time the identification, characterization and heterologous production of an enzyme capable of hydrolyzing SGs. A synthetic codon-optimized version of the lacS gene from Sulfolobus solfataricus was efficiently expressed and purified from Escherichia coli, and used to treat soybean derived biodiesel containing 100 ppm of SGs. After optimizing different variables, we found that at pH 5.5 and 87 °C, and in the presence of 0.9 % of the emulsifier polyglycerol polyricinoleate, 81 % of the total amount of SGs present in biodiesel were hydrolyzed by the enzyme. This remarkable reduction in SGs suggests a path for the removal of these contaminants from biodiesel on industrial scale using an environmentally friendly enzymatic process.

[Effect of intragastrically injection of phytoecdysteroids on some indicators of hormonal status in rats].

The experiment in vivo in growing male Wistar rats was carried out. The animals of the experimental 2-4 groups were daily intragastrically injected water solutions of the dried extract from the leaves of Seratulla coronata L. in volume of 1.0 ml, containing 2, 20 and 50 mg of phytoecdysteroids per kg of animal weight, accordingly. Animals of control group were daily injected 1.0 ml of water. The content of phytoecdysteroids in the dry extract was analyzed by high performance liquid chromatography (HPLC). The concentration of the sum of phytoecdysteroids in dry extract was 6.15%, 66% of which was 20-hydroxyecdysone and 23% was 25S-inokosteron. On the 15th day animals were taken out of the experiment by the decapitation. The content of corticosterone, prostaglandin E2 and beta-endorphin in rat blood plasma were determined by ELISA test. The pathological--anatomical analysis and weighing of the liver did not reveal any adverse changes of this organ in the animals of all groups. The average concentration of blood plasma corticosterone reduced with increasing of the dose of the extract injected to the animals, reaching significant differences relative to the control group (60.9 +/- 9.4 ng/ml) for 3 and 4 groups (22.7 +/- 6.6 and 17.6 +/- 7.3 ng/ml, accordingly). Beta-endorphin and prostaglandin E2 levels did not differ. The ratio of the mediator of stress (corticosterone) and inhibitors of stress (beta-endorphin and prostaglandin E2) has been calculated. A monotonic decrease of corticosterone/beta-endorphin and corticosterone/prostaglandin E2 ratio has been found with extract dose increasing. Taken together the results of determination of biochemical parameters of the general adaptation syndrome the dose-dependent stress-protective effect of Seratulla coronata L extract has been demonstrated.

The NHR-8 nuclear receptor regulates cholesterol and bile acid homeostasis in C. elegans.

Hormone-gated nuclear receptors (NRs) are conserved transcriptional regulators of metabolism, reproduction, and homeostasis. Here we show that C. elegans NHR-8 NR, a homolog of vertebrate liver X and vitamin D receptors, regulates nematode cholesterol balance, fatty acid desaturation, apolipoprotein production, and bile acid metabolism. Loss of nhr-8 results in a deficiency in bile acid-like steroids, called the dafachronic acids, which regulate the related DAF-12/NR, thus controlling entry into the long-lived dauer stage through cholesterol availability. Cholesterol supplementation rescues various nhr-8 phenotypes, including developmental arrest, unsaturated fatty acid deficiency, reduced fertility, and shortened life span. Notably, nhr-8 also interacts with daf-16/FOXO to regulate steady-state cholesterol levels and is synthetically lethal in combination with insulin signaling mutants that promote unregulated growth. Our studies provide important insights into nuclear receptor control of cholesterol balance and metabolism and their impact on development, reproduction, and aging in the context of larger endocrine networks.

Chemical characterization of a commercial Commiphora wightii resin sample and chemical profiling to assess for authenticity.

The gum resin of Commiphora wightii [(Hook. ex Stocks) Engl.] is an ayurvedic medicine for the treatment of arthritis, inflammation, obesity, lipid disorders, and cardiovascular diseases and is known as guggul. Morphologically, it is not easy to distinguish guggul from closely related gum resins of other plants. Reliability of the commercially available guggul is critical due to the high risk of adulteration. To check authenticity, a commercial guggul sample was investigated for its chemical markers and 17 metabolites were identified, including three new, 20(S),21-epoxy-3-oxocholest-4-ene (1), 8 ß-hydroxy-3,20-dioxopregn-4,6-diene (2), and 5-(13' Z-nonadecenyl)resorcinol (17) from the ethyl acetate soluble part. During the current study, compounds 14- 17 were identified as constituents of Mangifera indica gum, as an adulterant in the commercial guggul sample. This discovery highlighted the common malpractices in the trade of medicinal raw material in the developing world. The structures of the compounds were deduced by the spectroscopic technique and chemical methods, as well as by comparison with the reported data. The structure of 20(S),21-epoxy-3-oxocholest-4-ene (1) was also unambiguously deduced by single-crystal X-ray diffraction technique.

Nuclear hormone receptor regulation of microRNAs controls developmental progression.

In response to small-molecule signals such as retinoids or steroids, nuclear receptors activate gene expression to regulate development in different tissues. MicroRNAs turn off target gene expression within cells by binding complementary regions in messenger RNA transcripts, and they have been broadly implicated in development and disease. Here we show that the Caenorhabditis elegans nuclear receptor DAF-12 and its steroidal ligand directly activate promoters of let-7 microRNA family members to down-regulate the microRNA target hbl-1, which drives progression of epidermal stem cells from second to third larval stage patterns of cell division. Conversely, the receptor without the ligand represses microRNA expression during developmental arrest. These findings identify microRNAs as components of a hormone-coupled molecular switch that shuts off earlier developmental programs to allow for later ones.

[Studies on chemical constituents of Laurencia tristicha ( II )].

OBJECTIVE: To search for chemical constituents with structural diversity from Laurencia tristicha to supply for biological assay. METHOD: Compounds were isolated by means of column chromatography over normal phase silica gel and Sephadex LH-20, recrystallization and HPLC. Structures were identified by spectroscopic methods including 1D NMR, IR and MS. Cytotoxicities of the purified compounds were evaluated by MTT method. RESULT: Seven compounds were isolated from L. tristicha. Their structures were elucidated as cholesterol (1), cholesta- 5-en-3beta, 7alpha-diol (2), beta-stigmasterol (3), phytol (4), zeaxanthin (5), 4 -hydroxybenzaldehyde (6), indolyl-3-carbaldehyde (7). In the cytotoxic assay compound 2 was active against human cancer cell lines HCT-8, Bel-7402, BGc-823, A549 and HELA with IC50 values of 1.90, 2.02, 1.99, 6.52 and 1.20 microg x mL(-1), respectively. Compound 4 showed cytotoxicity against HCT-8 and HELA with IC50 value of 3.51 and 2.04 microg x mL(-1), and other compounds were inactive ( IC50 > 10 microg x mL(-1)). CONCLUSION: Compounds 1-7 were isolated from L. tristicha for the first time. In additon, compounds 2 and 4 were cytotoxic against several human cancer cell lines.