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Bile acids (BAs) are amphipathic molecules important for metabolism of cholesterol, absorption of lipids and lipid soluble vitamins, bile flow, and regulation of gut microbiome. There are over 30 different BA species known to exist in humans and mice, which are endogenous modulators of at least 6 different membrane or nuclear receptors. This diversity of ligands and receptors play important roles in health and disease; however, the full functions of each individual BA in vivo remain unclear. We generated a mouse model lacking the initiating enzymes, CYP7A1 and CYP27A1, in the two main pathways of BA synthesis. Because females are more susceptible to BA related diseases, such as intrahepatic cholestasis of pregnancy, we expanded this model into female mice. The null mice of Cyp7a1 and Cyp27a1 were crossbred to create double knockout (DKO) mice. BA concentrations in female DKO mice had reductions in serum (63%), liver (83%), gallbladder (94%), and small intestine (85%), as compared to WT mice. Despite low BA levels, DKO mice had a similar expression pattern to that of WT mice for genes involved in BA regulation, synthesis, conjugation, and transport. Additionally, through treatment with a synthetic FXR agonist, GW4064, female DKO mice responded to FXR activation similarly to WT mice., Graphical abstract A mouse model lacking the initiating enzymes, CYP7A1 and CYP27A1, in the two main pathways of BA synthesis was generated.Image 1

In the placenta, the breast cancer resistance protein (BCRP)/ABCG2 efflux transporter limits the maternal-to-fetal transfer of drugs and chemicals. Previous research has pointed to the estrogenic mycotoxin zearalenone as a potential substrate for BCRP. Here, we sought to assess the role of the BCRP transporter in the transplacental disposition of zearalenone during pregnancy. In vitro transwell transport assays employing BCRP/Bcrp-transfected Madine-Darby canine kidney cells and BeWo trophoblasts with reduced BCRP expression were used to characterize the impact of BCRP on the bidirectional transport of zearalenone. In both models, the presence of BCRP protein increased the basolateral-to-apical transport and reduced the apical-to-basolateral transport of zearalenone over a 2-h period. In vivo pharmacokinetic analyses were then performed using pregnant wild-type and Bcrp(−/−) mice after a single tail vein injection of zearalenone. Zearalenone and its metabolite α-zearalenol were detectable in serum, placentas, and fetuses from all animals, and β-zearalenol was detected in serum and fetuses, but not placentas. There were no significant differences in the maternal serum concentrations of any analytes between the two genotypes. In Bcrp(−/−) mice, the free fetal concentrations of zearalenone, α-zearalenol, and β-zearalenol were increased by 115%, 84%, and 150%, respectively, when compared with wild-type mice. Concentrations of free zearalenone and α-zearalenol were elevated 145% and 78% in Bcrp(−/−) placentas, respectively, when compared with wild-type placentas. Taken together, these data indicate that the placental BCRP transporter functions to reduce the fetal accumulation of zearalenone, which may impact susceptibility to developmental toxicities associated with in utero zearalenone exposure.

We provide novel insights into the function(s) of β-carotene-15,15′-oxygenase (CMOI) during embryogenesis. By performing in vivo and in vitro experiments, we showed that CMOI influences not only lecithin:retinol acyltransferase but also acyl CoA:retinol acyltransferase reaction in the developing tissues at mid-gestation. In addition, LC/MS lipidomics analysis of the CMOI −/− embryos showed reduced levels of four phosphatidylcholine and three phosphatidylethanolamine acyl chain species, and of eight triacylglycerol species with four or more unsaturations and fifty-two or more carbons in the acyl chains. Cholesteryl esters of arachidonate, palmitate, linoleate, and DHA were also reduced to less than 30% of control. Analysis of the fatty acyl CoA species ruled out a loss in fatty acyl CoA synthetase capability. Comparison of acyl species suggested significantly decreased 18:2, 18:3, 20:1, 20:4, or 22:6 acyl chains within the above lipids in CMOI-null embryos. Furthermore, LCAT, ACAT1 and DGAT2 mRNA levels were also downregulated in CMOI −/− embryos. These data strongly support the notion that, in addition to cleaving β-carotene to generate retinoids, CMOI serves an additional function(s) in retinoid and lipid metabolism and point to its role in the formation of specific lipids, possibly for use in nervous system tissue.

One approach to achieve continuous overproduction of lipids in microalgal “cell factories” relies upon depletion or removal of nutrients that act as competing electron sinks (e.g., nitrate and sulfate). However, this strategy can only be effective for bioenergy applications if lipid is synthesized primarily de novo (from CO2 fixation) rather than from the breakdown and interconversion of essential cellular components. In the marine diatom, Phaeodactylum tricornutum, it was determined, using 13C-bicarbonate, that cell growth in nitrate (NO 3 − )-deprived cultures resulted predominantly in de novo lipid synthesis (60 % over 3 days), and this new lipid consisted primarily of triacylglycerides (TAGs). Nearly complete preservation of 12C occurred in all previously existing TAGs in NO 3 − -deprived cultures and thus, further TAG accumulation would not be expected from inhibition of TAG lipolysis. In contrast, both high turnover and depletion of membrane lipids, phosphatidylcholines (PCs), were observed in NO 3 − -deprived cultures (both the headgroups and fatty acid chains), while less turnover was observed in NO 3 − replete cultures. Liquid chromatography-tandem mass spectrometry mass spectra and 13C labeling patterns of PC headgroups provided insight into lipid synthesis in marine diatoms, including suggestion of an internal pool of glycine betaine that feeds choline synthesis. It was also observed that 16C fatty acid chains incorporated into TAGs and PCs contained an average of 14 13C carbons, indicating substantial incorporation of 13C-bicarbonate into fatty acid chains under both nutrient states.

When grown for energy production instead for smoking, tobacco can generate a large amount of inexpensive biomass more efficiently than almost any other agricultural crop. Tobacco possesses potent oil biosynthesis machinery and can accumulate up to 40% of seed weight in oil. In this work, we explored two metabolic engineering approaches to enhance the oil content in tobacco green tissues for potential biofuel production. First, an Arabidopsis thaliana gene diacylglycerol acyltransferase (DGAT) coding for a key enzyme in triacylglycerol (TAG) biosynthesis, was expressed in tobacco under the control of a strong ribulose-biphosphate carboxylase small subunit promoter. This modification led to up to a 20-fold increase in TAG accumulation in tobacco leaves and translated into an overall of about a twofold increase in extracted fatty acids (FA) up to 5.8% of dry biomass in Nicotiana tabacum cv Wisconsin, and up to 6% in high-sugar tobacco variety NC-55. Modified tobacco plants also contained elevated amounts of phospholipids. This increase in lipids was accompanied by a shift in the FA composition favourable for their utilization as biodiesel. Second, we expressed in tobacco Arabidopsis gene LEAFY COTYLEDON 2 (LEC2), a master regulator of seed maturation and seed oil storage under the control of an inducible Alc promoter. Stimulation of LEC2 expression in mature tobacco plants by acetaldehyde led to the accumulation of up to 6.8% per dry weight of total extracted FA. The obtained data reveal the potential of metabolically modified plant biomass for the production of biofuel.

Extracts of Tripterygium wilfordii roots have a long history of use in traditional Chinese medicine and have shown great promise in recent clinical trials as a treatment for rheumatoid arthritis. The major active component of Tripterygium root extracts is the diterpenoid triptolide. This paper describes a method for the determination of triptolide in root extracts that is suitable for the analysis of many small samples simultaneously. Extracts are applied to aminopropyl solid-phase extraction (SPE) tubes that are then eluted with dichloromethane-methanol (49:1, v/v). The eluate is chromatographed on a pentafluorophenyl HPLC column using an acetonitrile:water gradient. Triptolide is quantified by ultraviolet detection at 219 nm. Using this method, it was shown that smaller diameter roots with secondary growth contained higher triptolide concentrations than larger roots. This suggests that roots to be used for production of the drug extract could be harvested while still small, which would reduce the growing time necessary and thus be economically beneficial for the growers.

Two cyanogenic glucosides, prunasin (2- β -glucopyranosyloxy-2-phyenylacetonitrile) and its malonic acid conjugate, pruasin 6′-malonate, have been isolated from the above ground parts of Lotononis fruticoides and L . aff. falcata (Fabaceae). The compounds were identified by means of 1 H and 13 C NMR spectroscopy.

The cyanogenic glucosides dhurrin [2S-β- d -glucopyranosyloxy-2-(4-hydroxy)-phenylacetonitrile] and taxiphyllin [2R-β- d -glucopyranosyloxy-2-(4-hydroxy) -phenylacetonitrile] have been isolated as the only cyanogenic glycosides from all parts of Suckleya suckleyana (dhurrin) and a herbarium specimen of Girgensohnia oppositiflora (taxiphyllin) of the Chenopodiaceae. The leaves of S. suckleyana contain the highest concentration of dhurrin followed by fruits, stems and roots.

The stilbene phytoalexin piceatannol was quantified by HPLC in extracts from sugarcane (Saccharum sp.) stalk tissue inoculated with the sugarcane pathogen Colletotrichum falcatum. In all three cultivars tested, piceatannol was first detectable 2-3 days after inoculation although levels varied considerably among experiments. Levels in the susceptible cultivar C.P. 33-807 were usually higher than in the less susceptible cultivar C.P. 33-224; C.P. 33-409 (resistant) was assayed only once, but levels in this cultivar were higher than in the other two cultivars. The results suggest that piceatannol may not be important in disease resistance in sugarcane, although the relatively large size of the tissue samples may have masked the significance of piceatannol, or the compound may vary in importance in different cultivars. Possibly piceatannol functions as a secondary defence mechanism.

Seed samples from 22 species of the Capparidaceae (eight genera), one Caricaceae, 259 Cruciferae (88 genera), two Moringaceae, three Phytolaccaceae, one Pittosporaceae, six Resedaceae, one Salvadoraceae and two Tropaeolaceae were analysed for total and individual glucosinolate compositions. Glucosinolates with a wide variety of both alkyl and aryl substituents were quantified by GC of their hydrolysis products and, in certain cases, were confirmed by mass spectrometry.

Piceatannol was isolated from sugarcane (Saccharum sp.) infected with Colletotrichum falcatum but not from healthy or wounded sugarcane, or C. falcatum itself. The compound inhibited both spore germination and germ tube growth of C. falcatum. This is the first report of a stilbene phytoalexin in the Poaceae.

Lipolysis of stored triacylglycerols provides lipid precursors for the assembly of apolipoprotein B (apoB) lipoproteins in hepatocytes. Abhydrolase domain containing 5 (ABHD5) is expressed in liver and facilitates the lipolysis of triacylglycerols. To study the function of ABHD5 in lipoprotein secretion, we silenced the expression of ABHD5 in McA RH7777 cells using RNA interference and studied the metabolism of lipids and secretion of apoB lipoproteins. McA RH7777 cells deficient in ABHD5 secreted reduced amounts of apoB, triacylglycerols, and cholesterol esters. Detailed analysis of liquid chromatography-mass spectrometry data for the molecular species of secreted triacylglycerols revealed that deficiency of ABHD5 significantly reduced secretion of triacylglycerols containing oleate, even when oleate was supplied in the culture medium; the ABHD5-deficient cells partially compensated by secreting higher levels of triacylglycerols containing saturated fatty acids. In experiments tracking the metabolism of [ 14 C]oleate, silencing of ABHD5 reduced lipolysis of cellular triacylglycerols and incorporation of intermediates derived from stored lipids into secreted triacylglycerols and cholesterol esters. In contrast, the incorporation of exogenous oleate into secreted triacylglycerols and cholesterol esters was unaffected by deficiency of ABHD5. These findings suggest that ABHD5 facilitates the use of lipid intermediates derived from lipolysis of stored triacylglycerols for the assembly of lipoproteins.

Des explants de soja sont utilises pour etudier l'influence des cytokinines et/ou des mineraux ainsi que la cinetique des changements dans les parametres physiologiques cles lies a la senescence des feuilles et au developpement des gousses. On etudie egalement le synergisme des cytokinines avec les mineraux apportes au niveau du xyleme

Plants in the genus Tripterygium, such as Tripterygium wilfordii Hook.f., have a long history of use in traditional Chinese medicine. In recent years there has been considerable interest in the use of Tripterygium extracts and of the main bioactive constituent, the diterpene triepoxide triptolide (1), to treat a variety of autoimmune and inflammation-related conditions. The main mode of action of the Tripterygium extracts and triptolide (1) is the inhibition of expression of proinflammatory genes such as those for interleukin-2 (IL-2), inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-alpha), cyclooxygenase-2 (COX-2) and interferon-gamma (IFN-gamma). The efficacy and safety of certain types of Tripterygium extracts were confirmed in human clinical trials in the US and abroad. Over 300 compounds have been identified in the genus Tripterygium, and many of these have been evaluated for biological activity. The overall activity of the extract is based on the interaction between its components. Therefore, the safety and efficacy of the extract cannot be fully mimicked by any individual constituent. This review discusses the biochemical composition and biological and pharmacological activities of Tripterygium extracts, and their main bioactive components.

The concept of growing crops for health rather than for food or fiber is slowly changing plant biotechnology and medicine. Rediscovery of the connection between plants and health is responsible for launching a new generation of botanical therapeutics that include plant-derived pharmaceuticals, multicomponent botanical drugs, dietary supplements, functional foods and plant-produced recombinant proteins. Many of these products will soon complement conventional pharmaceuticals in the treatment, prevention and diagnosis of diseases, while at the same time adding value to agriculture. Such complementation can be accelerated by developing better tools for the efficient exploration of diverse and mutually interacting arrays of phytochemicals and for the manipulation of the plant's ability to synthesize natural products and complex proteins. This review discusses the history, future, scientific background and regulatory issues related to botanical therapeutics.

The function of small intestinal monoacylglycerol lipase (MGL) is unknown. Its expression in this tissue is surprising because one of the primary functions of the small intestine is to convert diet-derived MGs to triacylglycerol (TG), and not to degrade them. To elucidate the function of intestinal MGL, we generated transgenic mice that over-express MGL specifically in small intestine (iMGL mice). After only 3 weeks of high fat feeding, iMGL mice showed an obese phenotype; body weight gain and body fat mass were markedly higher in iMGL mice, along with increased hepatic and plasma TG levels compared to wild type littermates. The iMGL mice were hyperphagic and displayed reduced energy expenditure despite unchanged lean body mass, suggesting that the increased adiposity was due to both increased caloric intake and systemic effects resulting in a hypometabolic rate. The presence of the transgene resulted in lower levels of most MG species in intestinal mucosa, including the endocannabinoid 2-arachidonoyl glycerol (2-AG). The results therefore suggest a role for intestinal MGL, and intestinal 2-AG and perhaps other MG species, in whole body energy balance via regulation of food intake as well as metabolic rate.

A herbicidal compound was isolated from extracts ofMatthiola incana and identified as sulforaphene (4-methylsulfinyl-3-butenyl isothiocyanate). The ED50 of this compound against velvetleaf seedlings was approximately 2×10(-4) M. Glucoraphenin, the glucosinolate that is the natural precursor of sulforaphene, was less phytotoxic, with an ED50 of near 6×10(-3)M.

Many plants have the capacity to release hydrogen cyanide (HCN) when the tissues are damaged. The entire plant or any plant part may exhibit this property. Most commonly the compounds responsible are cyanogenic glycosides [O-β-glycosides of α-hydroxynitriles (cyanohydrins)], relatively polar, water-soluble compounds, usually accompanied by β-glycosidases that cleave sugars from the glycosides (Fig. 1). Associated hydroxynitrile lyases catalyze decomposition of the resultant cyanohydrins to carbonyl compounds and free hydrogen cyanide; this last step also may occur spontaneously. About 60 cyanogenic glycosides are known from higher plants (Nahrstedt 1987; Seigler 1991); probably the best known of these is amygdalin, which is widespread in seeds of plants such as apples, peaches, cherries, and apricots. Examples of the different structural classes of cyanogenic compounds are given in Fig. 2. The ability to produce and accumulate cyanogenic glycosides is found in all major vascular plant groups (Hegnauer 1977; Saupe 1981; Seigler 1991). Several major reviews are available (Seigler 1977, 1981a,b; Conn 1979, 1980a,b, 1981a,b; Nahrstedt 1981, 1985, 1987; Vennesland et al. 1981; Evered and Harnett 1988).

Corrigendum Corrigendum to ‘‘Medicinal chemistry and pharmacology of genus Tripterygium (Celastraceae)’’ [Phytochemistry 68 (2007) 732–766] Anita M. Brinker , Jun Ma , Peter E. Lipsky , Ilya Raskin a,* a Biotechnology Center for Agriculture and the Environment, Furan Hall, Cook College, The State University of New Jersey, 59 Dudley Road, New Brunswick, NJ 08901-8520, USA b Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Rockville Pike, Bethesda, MD 20892, USA Available online 26 April 2007

Heating of intact cassava leaves causes liberation of hydrogen cyanide. This phenomenon appears to be caused by β-glucosidase-catalysed decomposition of the cyanogenic glycosides linamarin and lotaustralin. Because of these losses, many previously determined values for total nitrogen in cassava (and other cyanogenic plants) are probably in error as plant materials used for Kjeldahl determinations are often dried at 70–90°C. Liberation of cyanide from intact cassava leaves by heating at 80°C is more complete than liberation by the homogenisation methods commonly used. Homogenisation of cassava leaf tissues with liquid nitrogen or dry ice gives somewhat lower values, and these materials are often not readily available in areas where cassava is studied. The basis of a relatively simple procedure for the isolation of hydrogen cyanide from cassava leaves is suggested.

Summary Cholesterol is a critical component of cellular membranes, regulating assembly and function of membrane-based protein/lipid complexes. Many RNA viruses, including enteroviruses, remodel host membranes to generate organelles with unique lipid blueprints on which they assemble replication complexes and synthesize viral RNA. Here we find that clathrin-mediated endocytosis (CME) is harnessed by enteroviruses to traffic cholesterol from the plasma membrane (PM) and extracellular medium to replication organelles, where cholesterol then regulates viral polyprotein processing and facilitates genome synthesis. When CME is disrupted, cellular cholesterol pools are instead stored in lipid droplets, cholesterol cannot be trafficked to replication organelles, and replication is inhibited. In contrast, replication is stimulated in cholesterol-elevated cells like those lacking caveolins or those from Niemann-Pick disease patients. Our findings indicate cholesterol as a critical determinant for enteroviral replication and outline roles for the endocytic machinery in both the enteroviral life cycle and host cell cholesterol homeostasis.