[Promoting tanshinone synthesis of Salvia miltiorrhiza root by a seed endophytic fungus, Phoma herbarum D603].

The interaction of endophytes and host plant is an effective mean to regulate the growth and secondary metabolism of medicinal plants. Here we want to elucidate the effects and mechanism of Phoma herbarum D603 on the root development and tanshinone synthesis in root of Salvia miltiorrhiza by endophyte-plant coculture system. The mycelium of P. herbarum D603 was colonized in the root tissue space, and formed a stable symbiotic relationship with host plant. The in vitro activities analysis showed that the concentration of IAA produced by D603 can reach(6.45±0.23) µg·mL~(-1), and this strain had some abilities of phosphorus solubilization and siderophore production activities. The coculture experiment showed that strain D603 can significantly promote the synthesis and accumulation of tanshinones in the root of S. miltiorrhiza, in which after 8 weeks of treatment with D603, the content of tanshinone Ⅱ_A in the roots reached up to(1.42±0.59) mg·g~(-1). By the qRT-PCR analysis results, we found that D603 could improve the expression levels of some key genes(DXR, DXS, GGPP, HMGR, CPS) of tanshinone biosynthesis pathway in host plant S. miltiorrhiza, but the promoting effect mainly occurred in the early stage of the interaction, and the enzyme activity level decreased in varying degrees of the later stage. In summary, seed-associated endophyte P. herbarum D603 can promote the growth and root development of S. miltiorrhiza by producing hormones, promoting nutrient absorption and siderophore production, and promote the synthesis and accumulation of tanshinones by regulating the expression level of key genes in the synthetic pathway in S. miltiorrhiza.

A Multi-signal Fluorescent Probe with Multiple Binding Sites for Simultaneous Sensing of Cysteine, Homocysteine, and Glutathione.

A novel fluorescent probe was developed by integrating chlorinated coumarin and benzothiazolylacetonitrile and exploited for simultaneous detection of cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). Featuring four binding sites and different reaction mechanisms for different biothiols, this probe exhibited rapid fluorescence turn-on for distinguishing Cys, Hcy, and GSH with 108-, 128-, 30-fold fluorescence increases at 457, 559, 529 nm, respectively, across different excitation wavelengths. Furthermore, the probe was successfully applied to the fluorescence imaging of endogenous Cys and GSH and exogenous Cys, Hcy, and GSH in living cells.

Glycerol-3-phosphate metabolism plays a role in stress response in the red alga Pyropia haitanensis.

Glycerol-3-phosphate (G3P) has been suggested as a novel regulator of plant defense signaling, however, its role in algal resistance remains largely unknown. The glycerol kinase (also designated as NHO1) and NAD-dependent G3P dehydrogenase (GPDH) are two key enzymes involved in the G3P biosynthesis. In our study, we cloned the full-length cDNA of NHO1 (NHO1Ph ) and GPDH (GPDHP h ) from the red alga Pyropia haitanensis (denoted as NHO1Ph and GPDHP h ) and examined their expression level under flagellin peptide 22 (flg22) stimulation or heat stress. We also measured the level of G3P and floridoside (a downstream product of G3P in P. haitanensis) under flg22 stimulation or heat stress. Both NHO1Ph and GPDHP h shared high sequence identity and structural conservation with their orthologs from different species, especially from red algae. Phylogenetic analysis showed that NHO1s and GPDHs from red algae were closely related to those from animals. Under flg22 stimulation or heat stress, the expression levels of NHO1Ph and GPDHP h were up-regulated, G3P levels increased, and the contents of floridoside decreased. But the floridoside level increased in the recovery period after heat stress. Taken together, we found that G3P metabolism was associated with the flg22-induced defense response and heat stress response in P. haitanensis, indicating the general conservation of defense response in angiosperms and algae. Furthermore, floridoside might also participate in the stress resistance of P. haitanensis.

[Effect of astaxanthin on preeclampsia rat model].

The effect of astaxanthin on N(Ω)-nitro-L-arginine methyl ester (L-NAME) induced preeclampsia disease rats was investigated. Thirty pregnant Sprague-Dawley rats were randomly divided into three groups (n = 10): blank group, L-NAME group and astaxanthin group. From day 5 to 20, astaxanthin group rats were treated with astaxanthin (25 mg x kg(-1) x d(-1) x bw(-1)) from pregnancy (day 5). To establish the preeclamptic rat model, L-NAME group and astaxanthin group rats were injected with L-NAME (125 mg x kg(-1) x d(-1) x bw(-1)) from days 10-20 of pregnancy. The blood pressure and urine protein were recorded. Serum of each group was collected and malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide synthase (NOS) activities were analyzed. Pathological changes were observed with HE stain. The expression of NF-κB (nuclear factor kappa B), ROCK II (Rho-associated protein kinase II), HO-1 (heme oxygenase-1) and Caspase 3 were analyzed with immunohistochemistry. L-NAME induced typical preeclampsia symptoms, such as the increased blood pressure, urinary protein, the content of MDA, etc. Astaxanthin significantly reduced the blood pressure (P < 0.01), the content of MDA (P < 0.05), and increased the activity of SOD (P < 0.05) of preeclampsia rats. The urinary protein, NO, and NOS were also decreased. HE stain revealed that after treated with astaxanthin, the thickness of basilal membrane was improved and the content of trophoblast cells and spiral arteries was reduced. Immunohistochemistry results revealed that the expressions of NF-κB, ROCK II and Caspase 3 in placenta tissue were effectively decreased, and HO-1 was increased. Results indicated that astaxanthin can improve the preeclampsia symptoms by effectively reducing the oxidative stress and inflammatory damages of preeclampsia. It revealed that astaxanthin may be benefit for prevention and treatment of preeclampsia disease.

Gene mutation patterns and their prognostic impact in a cohort of 1185 patients with acute myeloid leukemia.

To evaluate the prognostic value of genetic mutations for acute myeloid leukemia (AML) patients, we examined the gene status for both fusion products such as AML1 (CBFα)-ETO, CBFß-MYH11, PML-RARα, and MLL rearrangement as a result of chromosomal translocations and mutations in genes including FLT3, C-KIT, N-RAS, NPM1, CEBPA, WT1, ASXL1, DNMT3A, MLL, IDH1, IDH2, and TET2 in 1185 AML patients. Clinical analysis was mainly carried out among 605 cases without recognizable karyotype abnormalities except for 11q23. Of these 605 patients, 452 (74.7%) were found to have at least 1 mutation, and the relationship of gene mutations with clinical outcome was investigated. We revealed a correlation pattern among NPM1, DNMT3A, FLT3, IDH1, IDH2, CEBPA, and TET2 mutations. Multivariate analysis identified DNMT3A and MLL mutations as independent factors predicting inferior overall survival (OS) and event-free survival (EFS), whereas biallelic CEBPA mutations or NPM1 mutations without DNMT3A mutations conferred a better OS and EFS in both the whole group and among younger patients < 60 years of age. The use of molecular markers allowed us to subdivide the series of 605 patients into distinct prognostic groups with potential clinical relevance.

[Advances on the genome of algae].

Algae possess complex and diverse biology and evolutionary history. They play an important role in the ecosystem. A mass of unique genes and biological processes also make them attractive. The application of high-throughput sequencing approaches to algal research has greatly contributed to the development of algal genomics and transcriptomics, as well as enriched the gene information of algae. In this article, we summarize the advances of algal genomics and transcriptomics, describe and compare the characteristics of different algae genomes, and introduce the application of expression sequence tags (ESTs), microarray and RNA sequencing technique to algal transcriptomics research. Furthermore, the advances of algal gene expression and small RNA are also reviewed in detail. At last, we discuss the challenges and future development of this area.

Bioinformatic and functional characterization of cyclic-di-GMP metabolic proteins in Vibrio alginolyticus unveils key diguanylate cyclases controlling multiple biofilm-associated phenotypes.

The biofilm lifestyle is critical for bacterial survival and proliferation in the fluctuating marine environment. Cyclic diguanylate (c-di-GMP) is a key second messenger during bacterial adaptation to various environmental signals, which has been identified as a master regulator of biofilm formation. However, little is known about whether and how c-di-GMP signaling regulates biofilm formation in Vibrio alginolyticus, a globally dominant marine pathogen. Here, a large set of 63 proteins were predicted to participate in c-di-GMP metabolism (biosynthesis or degradation) in a pathogenic V. alginolyticus strain HN08155. Guided by protein homology, conserved domains and gene context information, a representative subset of 22 c-di-GMP metabolic proteins were selected to determine which ones affect biofilm-associated phenotypes. By comparing phenotypic differences between the wild-type and mutants or overexpression strains, we found that 22 c-di-GMP metabolic proteins can separately regulate different phenotypic outputs in V. alginolyticus. The results indicated that overexpression of four c-di-GMP metabolic proteins, including VA0356, VA1591 (CdgM), VA4033 (DgcB) and VA0088, strongly enhanced rugose colony morphotypes and strengthened Congo Red (CR) binding capacity, both of which are indicators of biofilm matrix overproduction. Furthermore, rugose enhanced colonies were accompanied by increased transcript levels of extracellular polysaccharide (EPS) biosynthesis genes and decreased expression of flagellar synthesis genes compared to smooth colonies (WTpBAD control), as demonstrated by overexpression strains WTp4033 and ∆VA4033p4033. Overall, the high abundance of c-di-GMP metabolic proteins in V. alginolyticus suggests that c-di-GMP signaling and regulatory system could play a key role in its response and adaptation to the ever-changing marine environment. This work provides a robust foundation for the study of the molecular mechanisms of c-di-GMP in the biofilm formation of V. alginolyticus.

Antioxidative and Cytoprotective Effects of Ganoderma applanatum and Fomitopsis pinicola in PC12 Adrenal Phaeochromocytoma Cells.

Considering the impact of oxidative stress on the development of many diseases, together with the role of natural antioxidants in maintaining physiological balance in humans, medicinal mushrooms are potential sources of bioactive compounds against many diseases. In the present work, in vitro evaluation of the biological activities of the alcoholic extracts of two wild tree mushrooms, namely, Ganoderma applanatum and Fomitopsis pinicola, has been performed. Extraction of G. applanatum (GAE) and F. pinicola (FPE) was conducted with 60% ethanol and 100% ethanol sequentially. UPLC-MS/MS identification was conducted on the two mushrooms extracts. A total of 15 substances were identified in GAE, including 3 spiro meroterpenoids and 12 triterpenoids; a total of 14 chemical constituents were iden¬tified in FPE, including 8 triterpenoids, 4 triterpene glycosides, 1 lanosterol, and 1 lanostanoid. The resulting extracts were examined for their in vitro antioxidative and cytoprotective effects against AAPH-induced oxidative damage. Our results demonstrated that both extracts have potent antioxidative activities, when GAE was 0.2 mg/mL, the clearance rates of DPPH and ABTS have reached 93.34% and 99.93%, respectively. When FPE was 1.4 mg/mL and 0.6 mg/mL, the scavenging rates of DPPH and ABTS have reached 91.76% and 100%, respectively. Both the alcoholic extracts of G. applanatum and F. pinicola were able to protect the AAPH-induced damage and could effectively inhibit cell aging via ß-galactosidase (SA ß-gal) staining activity test and scanning electron microscopy analysis.

[Carrageenan oligosaccharides inhibit growth-factor binding and heparanase activity].

This study is designed to investigate the anti-tumor and anti-angiogenesis mechanism of carrageenan oligosaccharides. The effects of carrageenan oligosaccharides on basic fibroblast growth factor (bFGF) induced cell proliferation, heparanase activity and bFGF binding ability were evaluated in human cervical cancer cells (HeLa) and human umbilical vein endothelial cells (HUVEC). Results indicate that, at rational concentrations, carrageenan oligosaccharides showed low cytotoxic effect. At relatively low concentrations (0.2-200 microg x mL(-1)), these oligosaccharides could competitively bind bFGF and inhibit bFGF induced cell proliferation. In these samples, oligo-lambda-carrageenans (dp2-8) were the most potent bFGF antagonists. At concentration of 20 microg x mL(-1), their inhibitory ratio reached to 30%. The heparanase enzyme assay revealed that three kinds of carrageenan oligosaccharides showed different inhibitory activities to two cell lines. For HeLa cell, oligo-lambda-carrageenans showed highest inhibitory effect, but for HUVEC, oligo-kappa-carrageenans (dp9-17) were the best inhibitors. Current observations demonstrated that the biological activities of carrageenan oligosaccharides are closely related to the molecular weight, carbohydrate structure and the content and linking position of sulfur groups. Carrageenan oligosaccharides with high sulfate fraction, 2-8 units saccharide size and suitable molecular structure are able to achieve potent heparin sulfate-like compounds.

[Astaxanthin inhibits sodium azide-induced cytotoxicity in hepatocyte L-02 cells probably by H+ transferring function].

This study is to investigate the protective effect of astaxanthin against injured hepatocyte L-02 cells induced by sodium azide (NaN3) and reveal the possible mechanisms. Hepatocyte L-02 cells were exposed to 100 mmol.L-1 NaN3 with various concentrations of astaxanthin pre-incubated, then the cell viability was measured by MTT method; The level of reactive oxygen species (ROS) was determined by DCFH-DA method; The changes of mitochondrial membrane potential (MMP) and apoptosis ratio were detected by JC-1 method and Annexin V-FITC/PI double stain method, respectively. Results showed that after cells were exposed to 100 mmol.L-1 NaN3 for 3 hours, the cell viability significantly decreased; ROS level and the percentage of late phase apoptosis increased obviously; MMP was also declined. When cells were pretreated with astaxanthin, the cell damage and late phase apoptosis ratio reduced and MMP was maintained. However, the level of ROS showed insignificant decrease (P>0.05). The beneficial concentration of astaxanthin in improving cell viability and MMP was not in a dose dependent manner and the most effective of which was 0.10 nmol.L-1 (P<0.01). In order to reveal its possible non-antioxidant mechanism, mitochondrial membrane was imitated and H+ transferring function of astaxanthin was also detected by bilayer lipid membrane (BLM) method. Results showed that 2.0% astaxanthin could transfer H+ efficiently. These suggested the mechanisms of astaxanthin in protection of hepatocyte L-02 cells not via its ROS quenching capability but via its H+ transferring function, which improved the mitochondrial function and had the sequence biology effects.

Effect of Sargassum fusiforme polysaccharide on apoptosis and its possible mechanism in human erythroleukemia cells.

This study aimed to investigate the effects of Sargassum fusiforme polysaccharide (SFPS I, II, and III) on the apoptosis and regulation of human erythroleukemia (HEL) cells. The effect of different doses of SFPS on HEL cell growth was detected using the Cell Counting Kit-8 method, and apoptosis was detected by Hoechst staining. Cell cycle distribution and apoptosis were detected using flow cytometry. Expression of the cell cycle gene, p53, antiapoptotic genes, Bcl-xL and Bcl-2, and pro-apoptotic genes, Bax, Bad, and Caspase-3, as well as the expression of the corresponding proteins, were detected using real-time quantitative polymerase chain reaction (qPCR) and Western blot. The results showed that SFPS II and III decreased HEL cell viability and induced HEL cell apoptosis. Different concentrations of SFPS (I, II, and III) were detected that induced much less toxic effect in normal human embryonic lung (MRC-5) cells, and SFPS I increased cell proliferation, indicating its favorable selectivity towards cancer cells. The mechanism by which SFPS induced apoptosis was also found to be related to the induction of cell cycle arrest in the G0/G1 phase and the increased expression of apoptosis-related genes and proteins. We concluded that SFPS induces HEL cell apoptosis, possibly via activation of the Caspase pathway, providing the theoretical basis for the development of SFPS-based anti-tumor drug products.

[Anti-proliferation of human cervical cancer HeLa cell line by fascaplysin through apoptosis induction].

This study is to investigate the effect of fascaplysin on human cervical cancer cells (HeLa) in order to provide insights into the mechanisms of growth suppression involved in fascaplysin-mediated apoptosis. Cytotoxic activity of fascaplysin on HeLa cells was determined using MTT assay, cell cycle analysis, and apoptosis (Annexin V-FITC and PI double staining) studies. The role of the molecules in cell cycle regulation and apoptosis was analyzed by Western blotting and flow cytometry. Fascaplysin markedly inhibited HeLa cells proliferation in a dose-dependent manner, however, did not provoke G1 phase arrest in HeLa cells with downregulation of CDK4, cyclin D1 and CDK4-specific Ser795 pRb phosphorylation. Furthermore, fascaplysin induced significantly apoptosis evidenced by sub-G1 peak and Annexin V-FITC and PI double staining. The molecular mechanism of fascaplysin-induced apoptosis was characterized with the activation of caspase-3, -8, and -9, truncation of Bid, release of cytochrome c into cytosol, and down-regulation of Bcl-2 level. Fascaplysin exhibits anti-proliferation effect towards human cervical cancer HeLa cells through induction of apoptosis via extrinsic death pathway and mitochondrial pathway, but not arresting cell cycle progression at G1 phase. All together, these data sustain our contention that fascaplysin has anticancer properties and merits further investigation as a potential therapeutic agent.

[Clinical Application of R-ISS Staging System in 412 Newly Diagnosed Patients with Multiple Myeloma].

OBJECTIVE: To evaluate the prognostic value of R-ISS staging system in patients with newly diagnosed multiple myeloma (NDMM). METHODS: The Chinical data of 412 patients with NDMM in our hospital from May 2010 to May 2016 were retrospectively analyzed. All the patients received conventional chemotherapy or thalidomide or bortezomib-based chemotherapy. All the patients with NDMM were divided into R-ISS-Ⅰ, R-ISS-Ⅱ and R-ISS-Ⅲ groups according to R-ISS staging system on the basis of ISS staging system, cytogenetics and LDH level. The progression-free survival (PFS) time and overall survival(OS) of different groups were compared. RESULTS: Among all 412 patients, 76 were rated as R-ISS-Ⅰ, 259 as R-ISS-Ⅱ and 77 as R-ISS-Ⅲ. The median PFS time in 3 groups were 44, 25 and 14 months respectively (P<0.01). The median OS time of the 3 groups were not reached 54 and 25 months respectively (P<0.01). Further analysis also found that statistically different survival associated with different R-ISS groups in the conventional chemotherapy group (P<0.05), bortezomib-based chemotherapy group (P<0.01), thalidomide-based chemotherapy group (P<0.01), transplantation group (P<0.05), different-age stratified group (≤65y P<0.01, 66-75y P<0.01,≥76y P<0.01), damaged renal function group (P<0.01) and extramedullary infiltration group (P<0.01). CONCLUSION: PFS and OS in the patients with multiple myeloma were different among three distrinct R-ISS stages. The R-ISS staging system has important clinical significance for the prognosis evaluation of multiple myeloma.

[Proliferation inhibition of lambda-carrageenan oligosaccharides on HUVEC and expression of apoptotic relevant genes].

To study the anti-proliferation effect of lambda-carrageenan oligosaccharides (lambda-CO) on human umbilical vein endothelial cells (HUVECs) and expression of apoptotic relevant genes, the influence of lambda-CO on HUVECs proliferation was measured by MTT assay; apoptotic rate, cell cycle distribution and the level of active caspase-3 of HUVECs were analyzed using flow cytometry; the mRNA level of apoptosis related genes was determined by RT-PCR. At a high concentration of 1 mg x mL(-1), lambda-CO significantly inhibited the endothelial cell proliferation. Annexin-V FITC/PI double stain assay showed that when treated with 0, 0.8, 1 mg x mL(-1) of lambda-CO for 24 h, cell apoptotic rates were (1.67 +/- 1.6)%, (11.48 +/- 2.4)% and (13.81 +/- 2.2)%, respectively, when treated for 48 h, cell apoptotic rates were (2.02 +/- 2.3)%, (13.84 +/- 1.9)% and (38.72 +/- 2.5)%, respectively, cell cycle assay showed the decrease of cells in G0/G1 phase, and increase in S phase. Furthermore, we observed the level of active caspase-3 increased in a dose-dependent manner at 24 th and 48 th. RT-PCR results indicated that mRNA of TNFalpha, p53, caspase-8 and caspase-3 in cells increased after treated with lambda-CO. lambda-CO induce apoptosis of HUVECs in a dose-dependent way and arrests cells at S phase, which mainly due to the up-regulation of apoptotic genes such as TNFalpha, p53, caspase-8, caspase-3 and increase the level of active caspase-3.

[Chromosomal Abnormalities Associated with Clinical Outcome in Patients with Newly Diagnosed Multiple Myeloma].

OBJECTIVE: To investigate the prognostic value of karyotypic abnormalities in evaluation of prognosis of patients with multiple myeloma. METHODS: The clinical and laboratory data of patients with newly diagnosed multiple myeloma (NDMM) were retrospectively analyzed in our hospital from May 2010 to May 2016. Patients who carried t(4; 14), t(14; 16) or 17P- (at least one of them) were defined as the patients with high-risk karyotype, whereas patients characterized by the absence of the above-mentioned abnormalities were defined as patients with standard-risk karyotype. PFS (progression-free survival, PFS) and OS (over all survival, OS) time was compared between the 2 groups. RESULTS: There were 110 cases in the high-risk group, and 302 cases in the standard-risk group. The clinical characteristics, such as age, sex, ISS stage and treatment regimen etc were not statistically different between 2 groups. The median OS time of patients in the high-risk and standard-risk groups were 42 months (CI 95%: 34.375-49.625 months) and 53 months (CI 95%: 46.310-59.690 months) (P<0.05). The median PFS time of patients in the high-risk group and standard-risk groups was 21 months (CI95%: 17.198-24.802 months) and 27 months (CI95%: 23.406-30.594 months) (P<0.05). CONCLUSION: Among patients with newly diagnosed MM, the PFS and OS time in the patients with high-risk karyotype is shorter than that in patients with standard-risk karyotyp.

One-Step Bioconversion of Fatty Acids into C8-C9 Volatile Aroma Compounds by a Multifunctional Lipoxygenase Cloned from Pyropia haitanensis.

The multifunctional lipoxygenase PhLOX cloned from Pyropia haitanensis was expressed in Escherichia coli with 24.4 mg·L-1 yield. PhLOX could catalyze the one-step bioconversion of C18-C22 fatty acids into C8-C9 volatile organic compounds (VOCs), displaying higher catalytic efficiency for eicosenoic and docosenoic acids than for octadecenoic acids. C20:5 was the most suitable substrate among the tested fatty acids. The C8-C9 VOCs were generated in good yields from fatty acids, e.g., 2E-nonenal from C20:4, and 2E,6Z-nonadienal from C20:5. Hydrolyzed oils were also tested as substrates. The reactions mainly generated 2E,4E-pentadienal, 2E-octenal, and 2E,4E-octadienal from hydrolyzed sunflower seed oil, corn oil, and fish oil, respectively. PhLOX showed good stability after storage at 4 °C for 2 weeks and broad tolerance to pH and temperature. These desirable properties of PhLOX make it a promising novel biocatalyst for the industrial production of volatile aroma compounds.

Fascaplysin, a selective CDK4 inhibitor, exhibit anti-angiogenic activity in vitro and in vivo.

PURPOSE: This study was to evaluate the correlation of two important strategies, namely, cell cycle proliferation arrest and anti-angiogenesis. We chose fascaplysin, a marine natural product with selective CDK4 selective inhibition activity, to study its potential anti-angiogenesis effects in vivo and in vitro. METHODS: Chorioallantoic membrane (CAM) assay was initially used as an in vivo approach to evaluate anti-angiogenic activity of fascaplysin. In addition, human umbilical vein endothelial cell (HUVEC) line was used to further confirm the anti-angiogenic activity of fascaplysin in vitro. To explore the mechanism of anti-angiogenesis, we examined the effect of fascaplysin on vascular endothelial growth factor (VEGF) expression and secretion by hepatocarcinoma cells BeL-7402. RESULTS: The results of CAM assay suggested fascaplysin inhibited capillary plexus formation in a dose-dependent manner and suppressed VEGF in cross section. Moreover, the in vitro assay also confirmed that fascaplysin provided selective inhibition of endothelial cells proliferation towards tumor cells in low concentration. The immunocytochemical staining and ELISA verified fascaplysin could inhibit VEGF expression and secretion by BeL-7402. CONCLUSIONS: These findings strongly suggest that fascaplysin is a natural angiogenesis inhibitor.

[In vitro anti-angiogenic action of lambda-carrageenan oligosaccharides].

This study was designed to evaluate the inhibition effect of lambda-carrageenan oligosaccharides on neovascularization in vitro by chick chorioallantoic membrane (CAM) model and human umbilical vein endothelial cell ( HUVEC). lambda-Carrageenan oligosaccharides caused a dose-dependent decrease of the vascular density of CAM, and adversely affected capillary plexus formation. At a high concentration of 1 mg x mL(-1), this compound inhibited the endothelial cell proliferation, while low concentration of lambda-carrageenan oligosaccharides (< 250 microg x mL(-1)) affected the cell survival slightly (> 95%). Different cytotoxic sensitivity of lambda-carrageenan oligosaccharides in three kinds of cells was observed, of which HUVEC is the most sensitive to this oligosaccharides. The inhibitory action of lambda-carrageenan oligosaccharides on the endothelial cell invasion and migration was also observed at relatively low concentration (150 - 300 microg x mL(-1)) through down-regulation of intracellular matrix metalloproteinases-2 (MMP-2) expression on endothelial cells. Current observations demonstrated that lambda-carrageenan oligosaccharides are potential angiogenesis inhibitor with combined effects of inhibiting invasion, migration and proliferation.

Antioxidant activities of agaro-oligosaccharides with different degrees of polymerization in cell-based system.

The aim of the present study was to evaluate the antioxidant activity of agaro-oligosaccharides with different degrees of polymerizations (DPs) and establish a relationship between the activity and DPs. The attenuate effect of oligosaccharides on 1,1-diphenyl-2-picryl-hydrazyl (DPPH(*)) was initially assessed, and the result indicated that agarohexaose showed the highest scavenging DPPH(*) capability (IC(50)=1.85 mg/ml). Following that, the intracellular antioxidant ability of agaro-oligosacharides was investigated by using the dichlorofluorescein (DCF) assay in human liver cell L-02 system. Different levels of antioxidant activities of agaro-oligosaccharides with various DPs were observed, and their scavenging reactive oxygen species (ROS) capability was associated with the improvement of the cell viability. In these oligosaccharides, agarohexaose possessed the highest scavenging capability, which could reduce 50% of oxidants generated by H(2)O(2) at 1 mg/ml. Furthermore, the antioxidant effect of agarohexaose on the indirect oxidation of cells induced by antimycin A (AA) was also tested. The results showed that agarohexaose could scavenge ROS generated by electron leakage and protect cells against apoptosis induced by ROS. It is concluded that agaro-oligosaccharides are generally considered as novel antioxidants which could protect cell damage caused by reactive oxygen species, especially agarohexaose exhibiting most desirable effects.

Astaxanthin blocks preeclampsia progression by suppressing oxidative stress and inflammation.

To investigate the antioxidative effect of astaxanthin on Nω-nitro-L-arginine methyl ester (L-NAME)-induced preeclamptic rats. Cell survival, the level of reactive oxygen species (ROS) and the changes in mitochondrial membrane potential (MMP) were examined in astaxanthin and H2O2-treated human umbilical vein endothelial cells (HUVECs). The preeclamptic Sprague-Dawley (SD) rat model was established by injection of L­NAME and treatment with astaxanthin. The activities of malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide synthase (NOS) in serum were analyzed. Pathological changes were examined by hematoxylin and eosin (H&E) staining. The expression of nuclear factor (NF)­κB, Rho­associated protein kinase II (ROCK II), heme oxygenase­1 (HO­1) and caspase 3 in preeclamptic placentas were examined by immunohistochemistry. Astaxanthin significantly reduced H2O2­induced HUVEC cell death, decreased ROS and increased MMP. Astaxanthin significantly reduced blood pressure and the content of MDA, but significantly increased the activity of SOD in preeclamptic rats. The urinary protein and the level of NO and NOS were also decreased. H&E staining revealed that the thickness of the basilar membrane was increased, while the content of trophoblast cells and spiral arteries were reduced following astaxanthin treatment. Immunohistochemistry results showed that the expression of NF­κB, ROCK II and caspase 3 in preeclamptic placentas was significantly decreased after astaxanthin treatment, while HO­1 expression was increased. In conclusion, astaxanthin inhibited H2O2­induced oxidative stress in HUVECs. Astaxanthin treatment significantly improved L­NAME­induced preeclamptic symptoms and reduced the oxidative stress and inflammatory damages in preeclamptic placentas. Astaxanthin treatment may effectively prevent and treat preeclampsia.