[Changes in the Expression of AKT and ERK after the JSRV-Env-Induced Transfection of TC-1 and TC-1-Hyal2 Cells].

This study aims to explore the tumorigenic mechanism of the target cells following JSRV interaction with its receptor. We transfected mouse lung epithelial cells (TC-1) and mouse lung epithelial cells stably expressing sheep Hyal-2(TC-1-Hyal2)with JSRV-Env eukaryotic expression vector, measured the changes in the mRNA and protein expression of AKT(serine/threonine kinase)and ERK(extracellular signal-regulated kinase)in cellular signal transduction pathways, and analyzed the role of sheep Hyal-2in JSRV-Env-induced transformation of TC-1cells.First,TC-1and TC-1-Hyal2 cells were cultured in vitro and were each divided into pEGFP-C1-env transfection group,pEGFP-C1 transfection group, and untransfected group. The expression of key enzymes was determined by PCR and Western blotting. qPCR showed that, for both cell lines, compared with untransfected cells, the expression of AKT and ERK1/2mRNA was significantly increased in the pEGFP-C1-env transfected cells(P<0.05).Western blotting showed that, relative to untransfected cells, transfection with pEGFP-C1-env significantly increased p-Akt (S473)protein expression in both cell lines(P<0.05).Moreover, p-Akt (T308)and p-Erk1/2protein expression was increased significantly in the pEGFP-C1-env transfected TC-1cells(P<0.05),and very significantly in the pEGFP-C1-env transfected TC-1-Hyal2cells(P<0.01).Cells of each type transfected with the empty vector pEGFP-C1 and the untransfected cells did not show significant differences in their mRNA and protein levels of AKT and ERK(P >0.05).Thus, the expression of JSRV-Env in the cell lines TC-1and TC-1-Hyal2 activated the cellular signal transduction pathways Ras-Raf-MAPK and PI3K-Akt.The expression of AKT and ERK was significantly increased in pEGFP-C1-env transfected TC-1and TC-1-Hyal2 cells, but a greater increase was seen in the TC-1-Hyal2 cells.We speculate that Hyal2 plays a catalytic role in JSRV-Env-induced transformation of TC-1cells.

Quality assessment of Japanese knotweed (Fallopia japonica) grown on Prince Edward Island as a source of resveratrol.

Japanese knotweed (Fallopia japonica , also known as Polygonum cuspidatum) is a common invasive plant species on Prince Edward Island (PEI), Canada, whereas it has been used in Chinese medicine and more recently as a raw material for extracting resveratrol. This paper reports on the quantification of resveratrol, polydatin, emodin, and physcion in roots, stems, and leaves of Japanese knotweed samples from PEI and British Columbia (BC), Canada, and nine provinces of China, by ultraperformance liquid chromatography (UPLC). The results showed that the root contains a much higher level of resveratrol than the stem and leaf, and it is accumulated in its highest level in October. PEI-grown knotweed contains similar levels of resveratrol and polydatin compared to Chinese samples collected in the month of October, but the contents of the other anthraquinones (emodin and physcion) are different. As such, Japanese knotweed grown in PEI could be a commercially viable source of raw material for resveratrol production; however, caution has to be taken in harvesting the right plant species.

Transcriptional and metabolomic analysis of Ascophyllum nodosum mediated freezing tolerance in Arabidopsis thaliana.

BACKGROUND: We have previously shown that lipophilic components (LPC) of the brown seaweed Ascophyllum nodosum (ANE) improved freezing tolerance in Arabidopsis thaliana. However, the mechanism(s) of this induced freezing stress tolerance is largely unknown. Here, we investigated LPC induced changes in the transcriptome and metabolome of A. thaliana undergoing freezing stress. RESULTS: Gene expression studies revealed that the accumulation of proline was mediated by an increase in the expression of the proline synthesis genes P5CS1 and P5CS2 and a marginal reduction in the expression of the proline dehydrogenase (ProDH) gene. Moreover, LPC application significantly increased the concentration of total soluble sugars in the cytosol in response to freezing stress. Arabidopsis sfr4 mutant plants, defective in the accumulation of free sugars, treated with LPC, exhibited freezing sensitivity similar to that of untreated controls. The 1H NMR metabolite profile of LPC-treated Arabidopsis plants exposed to freezing stress revealed a spectrum dominated by chemical shifts (δ) representing soluble sugars, sugar alcohols, organic acids and lipophilic components like fatty acids, as compared to control plants. Additionally, 2D NMR spectra suggested an increase in the degree of unsaturation of fatty acids in LPC treated plants under freezing stress. These results were supported by global transcriptome analysis. Transcriptome analysis revealed that LPC treatment altered the expression of 1113 genes (5%) in comparison with untreated plants. A total of 463 genes (2%) were up regulated while 650 genes (3%) were down regulated. CONCLUSION: Taken together, the results of the experiments presented in this paper provide evidence to support LPC mediated freezing tolerance enhancement through a combination of the priming of plants for the increased accumulation of osmoprotectants and alteration of cellular fatty acid composition.

Liuwei Dihuang (LWDH), a traditional Chinese medicinal formula, protects against ß-amyloid toxicity in transgenic Caenorhabditis elegans.

Liuwei Dihuang (LWDH), a classic Chinese medicinal formula, has been used to improve or restore declined functions related to aging and geriatric diseases, such as impaired mobility, vision, hearing, cognition and memory. Here, we report on the effect and possible mechanisms of LWDH mediated protection of ß-amyloid (Aß) induced paralysis in Caenorhabditis elegans using ethanol extract (LWDH-EE) and water extract (LWDH-WE). Chemical profiling and quantitative analysis revealed the presence of different levels of bioactive components in these extracts. LWDH-WE was rich in polar components such as monosaccharide dimers and trimers, whereas LWDH-EE was enriched in terms of phenolic compounds such as gallic acid and paeonol. In vitro studies revealed higher DPPH radical scavenging activity for LWDH-EE as compared to that found for LWDH-WE. Neither LWDH-EE nor LWDH-WE were effective in inhibiting aggregation of Aß in vitro. By contrast, LWDH-EE effectively delayed Aß induced paralysis in the transgenic C. elegans (CL4176) model which expresses human Aß1-42. Western blot revealed no treatment induced reduction in Aß accumulation in CL4176 although a significant reduction was observed at an early stage with respect to ß-amyloid deposition in C. elegans strain CL2006 which constitutively expresses human Aß1-42. In addition, LWDH-EE reduced in vivo reactive oxygen species (ROS) in C. elegans (CL4176) that correlated with increased survival of LWDH-EE treated N2 worms under juglone-induced oxidative stress. Analysis with GFP reporter strain TJ375 revealed increased expression of hsp16.2::GFP after thermal stress whereas a minute induction was observed for sod3::GFP. Quantitative gene expression analysis revealed that LWDH-EE repressed the expression of amy1 in CL4176 while up-regulating hsp16.2 induced by elevating temperature. Taken together, these results suggest that LWDH extracts, particularly LWDH-EE, alleviated ß-amyloid induced toxicity, in part, through up-regulation of heat shock protein, antioxidant activity and reduced ROS in C. elegans.

[Screening of pancreatic lipase and alpha-glucosidase inhibitors from Chinese dietary herbs].

The present study was conducted to develop new inhibitors of pancreatic lipase and alpha-glucosidase from Chinese dietary herbs. Sixty-three dietary herbs from 39 taxonomic families were selected and extracted with aqueous ethanol or water. The extracts were then tested with in vitro enzyme assays for their ability to inhibit pancreatic lipase and alpha-glucosidase activities. Orlistat and acarbose were used as two positive controls. The extracts of Nelumbo nucifera, Curcuma longa, Piper longum and Morus alba showed strong pancreatic lipase inhibitory effects with IC50 at (28.00 +/- 5.51), (5.24 +/- 0.51), (14.76 +/- 2.58), (4.78 +/- 0.58), (3.41 +/- 0.67) mg x L(-1), respectively. These extracts also showed potent alpha-glucosidase inhibitory activities with IC50 at (1.98 +/- 0.13), (0. 18 + 0.007), (0.71 +/- 0.08), (0.077 +/- 0.005), (0.089 +/- 0.006) g x L(-1), respectively. The results provide useful information for developing new drugs or natural health products for hyperlipidemia and hypoglycemia from Chinese dietary herbs.

Carrageenans, sulphated polysaccharides of red seaweeds, differentially affect Arabidopsis thaliana resistance to Trichoplusia ni (cabbage looper).

Carrageenans are a collective family of linear, sulphated galactans found in a number of commercially important species of marine red alga. These polysaccharides are known to elicit defense responses in plant and animals and possess anti-viral properties. We investigated the effect of foliar application of ι-, κ- and λ-carrageenans (representing various levels of sulphation) on Arabidopsis thaliana in resistance to the generalist insect Trichoplusia ni (cabbage looper) which is known to cause serious economic losses in crop plants. Plants treated with ι- and κ-carrageenan showed reduced leaf damage, whereas those treated with λ- carrageenan were similar to that of the control. In a no-choice test, larval weight was reduced by more than 20% in ι- and κ- carrageenan treatments, but unaffected by λ-carrageenan. In multiple choice tests, carrageenan treated plants attracted fewer T. ni larvae by the fourth day following infestation as compared to the control. The application of carrageenans did not affect oviposition behaviour of T. ni. Growth of T. ni feeding on an artificial diet amended with carrageenans was not different from that fed with untreated control diet. ι-carrageenan induced the expression of defense genes; PR1, PDF1.2, and TI1, but κ- and λ-carrageenans did not. Besides PR1, PDF1.2, and TI1, the indole glucosinolate biosynthesis genes CYP79B2, CYP83B1 and glucosinolate hydrolysing QTL, ESM1 were up-regulated by ι-carrageenan treatment at 48 h post infestation. Gas chromatography-mass spectrometry analysis of carrageenan treated leaves showed increased concentrations of both isothiocyanates and nitriles. Taken together, these results show that carrageenans have differential effects on Arabidopsis resistance to T. ni and that the degree of sulphation of the polysaccharide chain may well mediate this effect.

Baicalin prevents the production of hydrogen peroxide and oxidative stress induced by Aß aggregation in SH-SY5Y cells.

Alzheimer's disease (AD) is a common form of neurodegenerative disease. Mounting evidence suggests that metal ions play a key role in the aggregation of amyloid ß peptide (Aß), which acts as a factor or cofactor in the etiopathogenesis of AD. Therefore, inhibition of Aß aggregation emerges as a potential approach for the treatment of AD. We have found that baicalin can interact with copper directly and inhibits Aß1-42 aggregation. In addition, baicalin protects SH-SY5Y cells from oxidative injuries induced by Aß1-42 aggregation through decreasing H(2)O(2) production that is normally formed as a deleterious by-product of beta amyloid aggregation and the formation of plaques. Taken together, these data indicate that baicalin may be a potential agent to inhibit Aß aggregation and thereby delay, mitigate or modify the progression of neurodegenerative diseases such as AD.

Silibinin: a novel inhibitor of Aß aggregation.

Alzheimer's disease (AD) is characterized by the abnormal aggregation of amyloid ß peptide (Aß) into extracellular fibrillar deposits known as amyloid plaque. Inhibition of Aß aggregation is therefore viewed as a potential method to halt or slow the progression of AD. It is reported that silibinin (silybin), a flavonoid derived from the herb milk thistle (Silybum marianum), attenuates cognitive deficits induced by Aß25-35 peptide and methamphetamine. However, it remains unclear whether silibinin interacts with Aß peptide directly and decreases Aß peptide-induced neurotoxicity. In the present study, we identified, through employing a ThT assay and electron microscopic imaging that silibinin also appears to act as a novel inhibitor of Aß aggregation and this effect showed dose-dependency. We also show that silibinin prevented SH-SY5Y cells from injuries caused by Aß(1-42)-induced oxidative stress by decreasing H(2)O(2) production in Aß(1-42)-stressed neurons. Taken together, these results indicate that silibinin may be a novel therapeutic agent for the treatment of AD.

Quantitative and qualitative determination of six xanthones in Garcinia mangostana L. by LC-PDA and LC-ESI-MS.

A new method was developed for the simultaneous analysis of six naturally occurring xanthones (3-isomangostin, 8-desoxygartanin, gartanin, alpha-mangostin, 9-hydroxycalabaxanthone and beta-mangostin). The quantitative determination was conducted by reversed phase high performance liquid chromatography with photodiode array detector (LC-PDA). Separation was performed on a Phenomenex Luna C18(2) (150 mm x 3.00 mm, 5 microm) column. The xanthones were identified by retention time, ultraviolet (UV) spectra and quantified by LC-PDA at 320 nm. The precision of the method was confirmed by the relative standard deviation (R.S.D.), which was < or =4.6%. The recovery was in the range from 96.58% to 113.45%. A good linear relationship was established in over two orders of magnitude range. The limits of detection (LOD) for six xanthone compounds were < or =0.248 microg/mL. The identity of the peaks was further confirmed by high performance liquid chromatography with time-of-flight mass spectrometry (LC-TOF MS) system coupled with electrospray ionization (ESI) interface. The developed methods were applied to the determination of six xanthones in Garcinia mangostana products. The satisfactory results showed that the methods are effective for the analysis of real samples.

Quantitative determination of triterpenes from Amphiptherygium adstringens by liquid chromatography and thin-layer chromatography and morphological analysis of cuachalalate preparations.

Amphiptherygium adstringens (Anacardiaceae/Julianaceae), local name "cuachalalate," is used in folk medicine for the treatment of cholelithiasis, fevers, fresh wounds, hypercholesterolemia, gastritis, gastric ulcers, and cancer of the gastrointestinal tract. The development of column high-performance liquid chromatography-photodiode array detector (LC-PDA) and high-performance thin-layer chromatography (HPTLC)-densitometry methods for the determination of masticadienonic acid and 3-hydroxymasticadienonic acid in cuachalalate preparations is described in this paper. Good separation of the compounds could be achieved by both methods. Either might be preparable depending on the requirements. The LC separation was performed on a Phenomenex Synergi MAX-RP 80A reversed-phase column operated at 40 degrees C with detection at 215 nm. The plant materials were extracted with methanol by sonication. The triterpenes present in the plant material and commercial extracts were separated with an acetonitrile-water reagent alcohol isocratic system. The limit of detection was 0.1-0.2 microg/mL. The relative standard deviation values for the determination of triterpenes in plant extracts were less than 1.00%. This is the first report of an analytical method developed for the quantitative analysis of triterpenes from Amphiptherygium adstringens by LC-PDA and HPTLC. The stem bark showed higher amounts of triterpenes, and low amounts in root and stem root. The microscopic description of the crude drug of cuachalalate was also provided.

Variability for the presence of pyrrolizidine alkaloids in Crotolaria juncea L.

Sunn hemp (Crotalaria juncea L.) is the most widely grown legume used as green manure in the tropics where it is also grown as a fiber and animal fodder crop. It has been reported that sunn hemp seeds contain several pyrrolizidine alkaloids that when ingested in sufficient amount can be toxic to animals and birds. No information is available regarding variability for the presences of the different types of pyrrolizidine alkaloids in the seeds. The objective of this research was to analyze sunn hemp seeds of nine populations that originated in different parts of the world for several pyrrolizidine alkaloids to determine their level of variability for the presence of these compounds and to quantify the total amount of pyrrolizidine alkaloids in the seeds. Of the nine pyrrolizidine alkaloids tested, the sunn hemp populations only had junceine and trichodesmine. PI 207657 had very low levels of both alkaloids and PI 314239, PI 322377, PI 346297, and the US cultivar Tropic Sun had very low levels of trichodesmine. Although juncein was present in higher amounts than trichodesmine in the seeds of most accessions, its value was deemed to be small. The amount of pyrrolizidine alkaloids present in the sunn hemp populations studied was low.

Quantitative determination of usnic acid in Usnea lichen and its products by reversed-phase liquid chromatography with photodiode array detector.

Usnic acid, a lichen substance, has a wide range of pharmaceutical applications, including antibiotic, antimycotic, antifeedant, antitubercular, antitumor, and analgesic activities. Some products containing usnic acid are marketed as weight control supplements; however, hepatotoxicity and acute liver failures were reported as severe side effects. The usnic acid content present in the plant materials and market products was analyzed by reversed-phase high-pressure liquid chromatography with a photodiode array detector at 233 nm. A Waters XTerra RP18 (150 x 4.6 mm; 5 microm particle size) column was the stationary phase; mobile phase was aqueous 0.1% acetic acid and acetonitrile gradient at flow rate of 1.0 mL/min. The temperature was held constant at 30 degrees C. The retention time of usnic acid was approximately 13.3 min. Acetone extraction of the samples took place with sonication. The precision of the method was confirmed by a standard deviation below 3.0% (n=3) and usnic acid recovery was 99.0%. Limit of detection was 0.4 microg/mL and the response was linear from 1.4 to 570.0 microg/mL with a correlation coefficient (R2) of 0.9991. The content of usnic acid in 4 raw materials and 22 finished products was analyzed.

Taxanes with C-5-amino-side chains from the needles of Taxus canadensis.

Five taxanes with an amino-side chain on C-5 were identified for the first time in the needles of the Canadian yew, Taxus canadensis. Their structures were characterized as 2alpha,7beta,9alpha,10beta,13-pentaacetoxy-11beta-hydroxy-5alpha-(3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),12-diene (1), 2alpha,9alpha-dihydroxy-10beta,13alpha-diacetoxy-5alpha-(3'-methylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (2), 2alpha17-dihydroxy-9alpha,10beta,13alpha-triacetoxy-5alpha-(3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (3), 2alpha-hydroxy-7beta,9alpha,10beta,13alpha-tetraacetoxy-5alpha-(2'-hydroxy-3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (4), and 9alpha-hydroxy-2alpha,10beta,13alpha-triacetoxy-5alpha-(3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene (5) on the basis of 1D-, 2D-NMR spectroscopic data and high-resolution fast atom bombardment MS analyses. Metabolite (1) was isolated from the needles of the Canadian yew for the first time but had previously been detected in the stems of the Japanese yew, whereas taxanes (2-5) are only now reported. Metabolite (3) is the first reported nitrogen-containing taxane with a 17-hydroxyl substitution.

Determination of flavonoids in Semen Cuscutae by RP-HPLC.

Flavonoids contents in 40 samples of Semen Cuscutae collected from areas all around China were investigated. Five principal flavonoids, quercetin 3-O-beta-D-galactoside-7-O-beta-D-glucoside, quercetin 3-O-beta-D-apiofuranosyl-(1-->2)-beta-D-galactoside, hyperoside, quercetin and kaempferol were analyzed simultaneously by using a reversed phase liquid chromatograph system with 0.025 M phosphoric acid-methanol as mobile phase. The recovery of the method was 97.0-102.9%, and all the flavonoids showed good linearity (r > or = 0.9990) in a relatively wide concentration range. The results indicated that contents of flavonoids in S. Cuscutae varied significantly from species to species, locality to locality, and parasiting host to host. Cuscuta australis contained a much higher content of kaempferol than C. chinensis, and few flavonoids were detected in C. japonica. The quality of S. Cuscutae can be evaluated according to the contents of flavonoids.