benzofurans and pinoresinol

The effects of phytochemicals (lignans and neolignans) are reviewed in a variety of insect species with special focus on the recent advances on feeding, excretion and Trypanosoma cruzi interactions with Rhodnius prolixus. Burchellin, podophyllotoxin, pinoresinol, sesamin, licarin A, and nordihydroguaiaretic acid (NDGA) added to the diet of Rhodnius prolixus larvae induce antifeedant effects only in doses up to 100 microg/ml of blood meal. Additionally, pinoresinol and NDGA significantly inhibit ecdysis (ED(50)<20 microg/ml). Simultaneous application of ecdysone (1 microg/ml) counteracts ecdysial stasis as induced by NDGA in 5th-instar larvae. Experiments in vivo demonstrate that burchellin and podophyllotoxin (100 microg/ml) diminish excretion post-feeding. Simultaneous treatment with 5-hydroxytryptamine (1 mM, 5-HT), a diuretic hormone, partially reverses this effect of burchellin. Experiments in vitro, using isolated Malpighian tubules of R. prolixus, indicate that burchellin (i) decreases diuretic hormone levels in the hemolymph but not the amount of diuretic hormone stored in the thoracic ganglionic masses (including axons); (ii) reduces the volume of urine secreted by isolated Malpighian tubules; and (iii) 5-HT therapy cannot overcome the effect of burchellin on the Malpighian tubules. In R. prolixus fed on blood containing T. cruzi epimastigotes, the number of parasites in the digestive tract decreases drastically in the presence of burchellin and NDGA (10 microg/ml). When these phytochemicals are applied 20 days after T. cruzi infection, burchellin significantly reduces the gut infection, whereas NDGA does not. However, if the insects are pretreated with both compounds 20 days before subsequent infection with epimastigotes, the parasite infection is almost completely abolished. The same holds true when 5th-instar of R. prolixus are inoculated with 0.5 microg/microl/larva of both neolignans 1 day before infection. Taken together, these findings not only provide a better understanding of the lignoid function in insects, but also offer novel insights into basic physiological processes, which make lignoids interesting candidates for new types of insecticides.

Topics: Animals; Benzofurans; Dioxoles; Feeding Behavior; Furans; Host-Parasite Interactions; Insecta; Larva; Lignans; Malpighian Tubules; Masoprocol; Molting; Podophyllotoxin; Rhodnius; Trypanosoma cruzi

The liver X receptors (LXRs) are major regulators of lipogenesis, and their reduced activation by an inhibitor could be a treatment strategy for fatty liver disease. Small molecules originating from dietary food are considered suitable and attractive drug candidates for humans in terms of safety. In this study, an edible plant,

Topics: Acetyl-CoA Carboxylase; Animals; Benzofurans; Diet, High-Fat; Fatty Acid Synthases; Furans; Humans; Lignans; Lipogenesis; Liver; Liver X Receptors; Male; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Plant Extracts; Primulaceae; Sterol Regulatory Element Binding Protein 1; Triglycerides

To investigate the chemical constituents of Selaginella sinensis (Desv.) Spring.. Chromatographic separations on Diaion HP-20, silica gel, and Sephadex LH-20 were used. The structures of the isolates were elucidated on the basis of spectroscopic analysis, as well as chemical methods.. Eight compounds were obtained and their structures were identified as sinensioside A (1), syringaresinol-4- O-β-D-glucopyranoside (2), (+)-medioresinol-4-O-β-D-glucopyranoside (3), pinoresinol-4, 4'-di-O-β-D-glucopyranoside (4), quercetin (5), eucomic acid (6), shikimic acid (7), and 2, 3-dihydroamentoflavone (8).. Compound 1 is a new dihydrobenzofuran sesquilignan glycoside from Selaginella sinensis.

Topics: Benzofurans; Furans; Glucosides; Lignans; Molecular Structure; Plant Extracts; Plant Stems; Quercetin; Selaginellaceae

Two new compounds, (2S,3R)-methyl 7-hydroxy-2-(4-hydroxy-3-methoxy-phenyl)-3-(hydroxymethyl)-2,3-dihydrobenzofuran-5-carboxylate (1) and (4R,5S)-5-(3-hydroxy-2,6-dimethylphenyl)-4-isopropyldihydrofuran-2-one (2), tentatively named norcurlignan and limlactone, respectively, were isolated from Liriope muscari, together with the known compound (-)-pinoresinol (3). The structures of these compounds were elucidated and characterized on the basis of 1D NMR, 2D NMR, CD and MS data. The in vitro antioxidant activities of compounds 1-3 were assessed by the DPPH and ABTS scavenging methods.

Topics: Benzofurans; Benzothiazoles; Biphenyl Compounds; Chromatography, Gel; Free Radical Scavengers; Free Radicals; Furans; Lignans; Liriope Plant; Magnetic Resonance Spectroscopy; Medicine, Chinese Traditional; Molecular Conformation; Molecular Structure; Picrates; Sulfonic Acids

The effects of six lignans and neolignans as inhibitors of ecdysis and on the water balance in fourth-instar larvae of Rhodnius prolixus were studied by oral, topical and continuous contact treatments. The main results may be summarised as follows: (i) burchellin, pinoresinol, sesamin, licarin A and nordihydroguaiaretic acid (NDGA) did not cause feeding inhibition at doses of 100 micrograms/ml blood; podophyllotoxin had no antifeedant effect but caused a high moulting inhibition and significant toxicity when applied either orally or topically; (ii) the highest ecdysis inhibitory effects were observed with pinoresinol and NDGA when applied orally at a dose of 100 micrograms/ml (58% and 50% of moulting inhibition, respectively); burchellin inhibited 30% of the moulting at this concentration; (iii) by topical treatment none of the compounds presented any influence on the moulting cycle; and (iv) podophyllotoxin and burchellin significantly reduced the excretion of the insect in 24 h; the other compounds had no effect on excretion. The implications of these findings in relation to the pertinent biological events in R. prolixus are discussed.

Topics: Animals; Benzofurans; Dioxoles; Feeding Behavior; Furans; Larva; Lauraceae; Lignans; Masoprocol; Plants, Medicinal; Podophyllotoxin; Rhodnius