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The buoyancy of Microcystis colonies determines the occurrence and dominance of bloom on the water surface. Besides the cell density regulation and the formation of larger size aggregates, increases in cell volume per colony (Vcell) and the colony's compactness (i.e., volume ratio of cells to the colony, VR) may promote Microcystis colony buoyancy. Yet only a few studies have studied the relationship between the internal structure variation of colonies and their buoyancy, and the co-regulatory role of Vcell and VR of Microcystis colonies in the floating velocity (FV) remains largely unexplored. In the present study, we optimized a method for measuring the compactness of Microcystis colonies based on the linear relationship between total Vcell and chlorophyll a. Different relationships between the VRs and FVs were observed with different colony size and Vcell range groups. Both field and laboratory experiments showed that FV/(D50, median diameter)2 had a significant linear relationship with VR, indicating that the cell density and extracellular polysaccharides were unchanged over a short time period and could be estimated via the slope and intercept of a fitted line. We also constructed a functional relationship between FV, VR, and Vcell and found that high VR and Vcell can promote Microcystis buoyancy. This means that increasing cell compactness or Vcell may be an active regulation strategy for Microcystis colonies to promote buoyancy. Therefore, quantifying the internal structure of Microcystis colonies is strongly recommended for the assessment of Microcystis bloom development and their management. Graphical abstract.

Background Collagen peptides (CP) have been shown to protect against osteoporosis. Yet, its mechanism on anti-osteoporosis remains unclear. Method Cell viability, levels of alkaline phosphatase (ALP), reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) of hydrogen peroxide (H2O2)-induced oxidative stress in Saos-2 cells pretreated with CP were examined. The effect and regulatory of CP on FBXW7-p100-NF-κB axis and the relationship between the molecules were explored by overexpressing FBXW7, silencing p100 or NF-κB in Saos-2 cells. Western blot and RT-PCR were performed to determine the expressions of FBXW7, p100 and NF-κB. Hematoxylin & Eosin (H&E) staining was performed to determine morphological indexes of bone tissues in ovariectomized-induced osteoporosis rats treated with CP. Result CP increased cell viability, ALP and antioxidant activities in H2O2-induced oxidative stress in Saos-2 cells. Results on cell viability, ALP, antioxidant levels, protein and gene expression levels in FBXW7-overexpressed, p100-silenced and NF-κB-silenced Saos-2 cells indicate that FBXW7, p100 and NF-κB are the key regulators and CP treatment modulates FBXW7-p100-NF-κB axis in Saos-2 cells. In addition, pretreatment and treatment with CP in ovariectomized rats improved osteoporosis. Conclusion CP could effectively prevent and alleviate osteoporosis. The protective effect of CP on osteoporosis was achieved in part by inhibiting oxidative damage of osteoblasts and promoting bone formation.

Lake Caohai has experienced extensive Microcystis blooms in recent years, and to improve its water quality, the local government carried out a series of water control measures. To better understand the dynamics of both pelagic and benthic Microcystis and their characteristics in Lake Caohai, we conducted a 1-year investigation from December 2015 to December 2016 to gain a seasonal outlook on the distribution and dynamics of cell abundance, colony size and intracellular microcystins (MCs) of Microcystis. The results indicated that the Microcystis bloom occupied primarily the northeastern region and then moved gradually from lakeshore to lake center. The perennial southwesterly winds and the water inflow from northeast to southwest in Lake Caohai determined the spatiotemporal distribution of pelagic Microcystis. Benthic Microcystis was mainly distributed in the northeastern region in summer, occupied the lake center in autumn and then occupied the southeastern region in winter, determined by the sedimentation of pelagic Microcystis and the death of benthic Microcystis. Small colonies (20–60 μm) overwintered more easily in both water column and sediment. The concentrations of intracellular toxin of benthic Microcystis were observed to be significantly higher than those of pelagic Microcystis. This might be because Microcystis synthesized large amount of MCs to acclimate to an unfavorable benthic environment. This knowledge on the dynamics of Microcystis expands our understanding of mechanisms underpinning the formation of Microcystis blooms.

Microcystis is one of the most common bloom-forming cyanobacteria in freshwater ecosystems throughout the world. However, the underlying life history mechanism and distinct temporal dynamics (inter- and intra-annual) of Microcystis populations in different geographical locations and lakes remain unclear but is critical information needed for the development of robust prediction, prevention, and management strategies. Perennial observations indicate that temperature may be the key factor driving differences in the overwintering strategy. This study quantitatively compared the overwintering abilities of Microcystis aeruginosa (Ma) in both the water column and sediments under a gradient of overwintering water temperatures (i.e., 4, 8, and 12 °C) using the death and proliferation rates of Ma. The results show that the dynamics of the Microcystis overwintering strategy were significantly affected by water temperatures. At 4 and 8 °C, Ma mainly overwintered in sediments and disappeared from the water column after exposure to low temperatures for a long duration, although some Microcystis cells can overwinter in the water column for short durations at low temperatures. At 12 °C, most Ma can overwinter in the water column. Rising temperatures promoted the proliferation of pelagic Ma but accelerated the death of benthic Ma. With warmer winter temperatures, pelagic Microcystis might become the primary inoculum sources in the spring. Our study highlights the overwintering strategy flexibility in explaining temporal dynamics differences of Microcystis among in geographical locations and should be considered in the context of global warming.

Adsorption mechanism and competitive adsorption of NH3 and As2O3 molecules on CuO (111) surface were investigated via density functional theory (DFT) simulations. The adsorption configuration, adsorption energy, electronic gains/losses, and projected density of states were thoroughly discussed. Results showed that As2O3 molecule was more likely to adsorb on CuO surface than NH3 molecule. For the adsorption of As2O3 on CuO surface, the “Osuf-Osuf bridge” site was the active site with the chemical adsorption energy of −1.39 eV. In the process of NH3 adsorption on CuO surface, N-Cu bond was formed in chemical adsorption, which was mainly attributed to the charge transfer from NH3 molecule to substrate surface. However, no obvious structural change occurred in physisorption. Thermodynamic analysis indicated that physisorption was the primary form for the adsorption of NH3 and As2O3 molecules on CuO surface under the actual SCR condition.

Dynamic control of thioredoxin (Trx) oxidoreductase activity is essential for balancing the need of cells to rapidly respond to oxidative/nitrosative stress and to temporally regulate thiol-based redox signaling. We have previously shown that cytokine stimulation of the respiratory epithelium induces a precipitous decline in cell S-nitrosothiol, which depends upon enhanced Trx activity and proteasome-mediated degradation of Txnip (thioredoxin-interacting protein). We now show that tumor necrosis factor-α–induced Txnip degradation in A549 respiratory epithelial cells is regulated by the extracellular signal-regulated protein kinase (ERK) mitogen-activated protein kinase pathway and that ERK inhibition augments both intracellular reactive oxygen species and S-nitrosothiol. ERK-dependent Txnip ubiquitination and proteasome degradation depended upon phosphorylation of a PXTP motif threonine (Thr(349)) located within the C-terminal α-arrestin domain and proximal to a previously characterized E3 ubiquitin ligase–binding site. Collectively, these findings demonstrate the ERK mitogen-activated protein kinase pathway to be integrally involved in regulating Trx oxidoreductase activity and that the regulation of Txnip lifetime via ERK-dependent phosphorylation is an important mediator of this effect.

The responses of denitrifiers and denitrification ability to dissolved oxygen (DO) concent in different layers of surface lake sediments are still poorly understood. Here, the optimal denitrification condition was constructed based on response surface methodology (RSM) to analyze the denitrification characteristics of surface sediments. The aerobic zone (AEZ), hypoxic zone (HYZ), up-anoxic zone (ANZ-1) and sub-anoxic zone (ANZ-2) were partitioned based on the oxygen contents, and sediments were collected using a customized-designed sub-millimeter scale sampling device. Integrated real-time quantitative PCR, Illumina Miseq-based sequencing and denitrifying enzyme activities analysis revealed that denitrification characteristics varied among different DO layers. Among the four layers, the DNA abundance and RNA expression levels of norB, nirS and nosZ were the highest at the aerobic layer, hypoxic layer and up-axoic layer, respectively. The hypoxia and up-anaerobic layer were the active nitrogen removal layers, since these two layers displayed the highest DNA abundance, RNA expression level and enzyme activities of denitrification functional genes. The abundance of major denitrifying bacteria showed significant differences among layers, with Azoarcus, Pseudogulbenkiania and Rhizobium identified as the main nirS, nirK and nosZ-based denitrifiers. Pearson’s correlation revealed that the response of denitrifiers to environmental factors differed greatly among DO layers. Furthermore, napA showed higher DNA abundance and RNA expression level in the aerobic and hypoxic layers than anaerobic layers, indicating that aerobic denitrifiers might play important roles at these layers. Electronic supplementary material The online version of this article (10.1186/s13568-019-0855-9) contains supplementary material, which is available to authorized users.

Removing the extensively accumulated cyanobacteria from lake is a straightforward means to tackle cyanobacterial blooms. However, developing removal technology with both high removal efficiency and large treatment capacity remains a great challenge. We developed a shipboard rotary drum filter (RDF) with a 35-mu m screen to remove cyanobacterial blooms at a flow rate of 900 m(3)/h in Lake Dianchi (Kunming, China). Nevertheless, the chlorophyll a (chl.a) concentration of the effluent was approximately 50 mu g/L, which is higher than the control target of 20 mu g/L. In this study, we aimed to improve the performance of RDF on cyanobacterial removal by the utilization of cationic polyacrylamide (CPAM). High molecular weight CPAM with a 30% cationic degree exhibited excellent flocculation effectiveness, with low flocculant doses, large sized flocs, short flocculation time, and high resistance to shear forces. Both the filtration rate and the cyanobacteria removal efficiency of the 35-mu m screen were notably improved by 1 mg/L of CPAM. After being added before the water inlet pump and being agitated by the pump impellers, the CPAM could effectively flocculate cyanobacteria particles at a hydraulic retention time shorter than 20 s. Chl.a concentration and turbidity in the effluents of the shipboard RDF were reduced to lower than 20 mu g/L and 12 NTU, respectively. Thus, a shipboard RDF coupled with CPAM flocculation is a promising approach to the removal of cyanobacterial blooms.

As a novel class of noncoding RNAs (ncRNAs), circular RNAs (circRNAs) have been verified to be potential biomarkers and therapeutic targets for human malignant tumors. However, the thorough understanding of circRNAs in the progression of esophageal squamous cell carcinoma (ESCC) still needs to be improved. This study focused on exploring the function and mechanism of circVRK1 in ESCC. At first, we examined the expression level of circVRK1 in ESCC tissues and cell lines with qRT-PCR. We found that circVRK1 was downregulated in ESCC tissues and cell lines. Kaplan-Meier method was used to analyze the correlation between circVRK1 expression and the overall survival of ESCC patients. Functionally, overexpression of circVRK1 suppressed the cell proliferation, migration and epithelial-mesenchymal transition (EMT) and reversed the radioresistance. Therefore, we identified the tumor suppressive role of circVRK1 in ESCC progression. Mechanistically, circVRK1 positively regulated PTEN by acting as a molecular sponge of miR-624-3p. Moreover, circVRK1 decreased the activity of PI3K/AKT signaling pathway by upregulating PTEN. Rescue assays were carried out to confirm the function of circVRK1-miR-624-3p-PTEN axis in ESCC progression. Our findings showed that circVRK1 suppressed ESCC progression by regulating miR-624-3p/PTEN axis and PI3K/AKT signaling pathway, suggesting the potential therapeutic value of circVRK1 for ESCC.

Light availability is an important driver of algal growth and for the formation of surface blooms. The formation of Microcystis surface scum decreases the transparency of the water column and influences the vertical distribution of light intensity. Only few studies analysed the interactions between the dynamics of surface blooms and the light distribution in the water column. Particularly the effect of light attenuation caused by Microcystis colonies (self-shading) on the formation of surface scum has not been explored. In the present study, we simulate the effect of variable cell concentration of Microcystis colonies on the vertical distribution of light in the water column based on experimental estimates of the extinction coefficient of Microcystis colonies. The laboratory observations indicated that higher cell concentration of Microcystis enhance the light attenuation in water column and promotes surface scum formation. We extended an existing model for the light-driven migration of Microcystis by introducing the effect of self-shading and simulated the dynamics of vertical migration for different cell concentrations and different colonial morphologies. The simulation results show that high cell concentrations of Microcystis promote surface scum formation, as well as its persistence throughout diel photoperiods. Large and tight Microcystis colonies facilitate scum formation, while small and loose colonies increase scum stability and persistence. This study reveals a positive feedback regulation of Microcystis surface scum formation and stability by self-shading and provides novel insights into the underlying mechanisms.

Cationic polyacrylamide (CPAM) can induce efficient harvest of microalgae at low dosages (0.5–2 mg/L), and the large flocs that form as a result are beneficial for later screen filtration. However, flocculation is dependent on the microalgae species, especially their extracellular organic matter (EOM). In this study, harvesting of microalgae with CPAM flocculation and screen filtration (100-μm pore size) was compared, using four cyanobacteria species (Microcystis aeruginosa, M. wesenbergii, Cylindrospermopsis raciborskii, and Phormidium ambiguum) and three green algae species (Chlorella vulgaris, Scenedesmus quadricauda, and Pediastrum duple). The influence of EOM concentration and characteristics (i.e. charge density and molecular weight) was of particular focus in this study. All cyanobacteria were effectively flocculated with 1–2 mg/L CPAM, though the retention of C. raciborskii (78%) was significantly lower than the others (>90%). For green algae, only Ch. vulgaris could be effectively flocculated with retention > 90%, but a higher CPAM dosage (4 mg/L) was required. When mixed with EOM of other microalgae, the retention of S. quadridcauda and P. duple increased to > 78%. Successful retention was highly correlated with high molecular weight (MW) and negative charge density of the EOM. The > 100 kDa EOM fractions were responsible for effective retention of cyanobacteria and 30–100 kDa EOM fractions for Ch. vulgaris, while these fractions were rarely present in the EOM of S. quadricauda and P. duple. Though effective for cyanobacteria, the application of CPAM flocculation and screen filtration for harvesting some green algae is limited due to a lack of high-MW and negatively charged EOM components.

Lung cancer has higher morbidity and mortality than most cancers. It is common that there are some phenomenons of secondary drug resistance, radiotherapy resistance and poor prognosis during the treatment of small cell lung cancer (SCLC). Recent studies revealed that the single-nucleotide polymorphisms (SNPs) are associated with the curative effect among patients with the same pathological type and stage. Our study analyzed the start time of radiotherapy and the relationship between PTEN gene rs2299939 polymorphisms and survival time among 116 SCLC patients. The results showed that early radiotherapy significantly improved the time of survival in patients compared with late radiotherapy ( P = 0.029). Simultaneously, the study found that patients with the rs2299939 AA genotype showed significant sensitivity to both early and late radiotherapy, but early radiotherapy is better. The median survival time of CC genotype patients was 12 months in the early radiotherapy group while it was 9 months in the late radiotherapy group, thus recommending early radiotherapy among these patients. In addition, it was found that rs2299939 could regulate the expression of related genes in peripheral blood and lung tissues by eQTL analysis. This study revealed that the early radiotherapy could prolong the PFS of SCLC and shall be performed in SCLC treatment.

AD-1, an aerobic denitrifier, was isolated from activated sludge and identified as Pseudomonas stutzeri. AD-1 completely removed NO3– or NO2– and removed 99.5% of NH4+ during individual culturing in a broth medium with an initial nitrogen concentration of approximately 50 mg L−1. Results showed that larger amounts of nitrogen were removed through assimilation by the bacteria. And when NH4+ was used as the sole nitrogen source in the culture medium, neither NO2– nor NO3– was detected, thus indicating that AD-1 may not be a heterotrophic nitrifier. Only trace amount of N2O was detected during the denitrification process. Single factor experiments indicated that the optimal culture conditions for AD-1 were: a carbon-nitrogen ratio (C/N) of 15, a temperature of 25°C and sodium succinate or glucose as a carbon source. In conclusion, due to the ability of AD-1 to utilize nitrogen of different forms with high efficiencies for its growth while producing only trace emissions of N2O, the bacterium had outstanding potential to use in the bioremediation of high-nitrogen-containing wastewaters. Meanwhile, it may also be a proper candidate for biotreatment of high concentration organic wastewater.

Microalgae are a promising sustainable source of biomass while large-scale harvesting of microalgal biomass is a major technological and economic challenge. In this study, a flocculation method and mechanism for the formation of compact mega flocs was developed using two oppositely charged polyelectrolytes, quaternary ammonium chitosan (N-[(2-hydroxy-3-trimethyl ammonium) propyl] chitosan, HTCC) and xanthan gum (XG). With 8 mg/L HTCC and 16 mg/L XG, Scenedesmus cells could be flocculated into mega flocs with diameters larger than 5 mm and were harvested by 500-μm-pore-sized sieves with an efficiency over 95%. The flocs were generated within 12 s and resisted strong hydraulic shear (stirring at 960 rpm), reducing energy consumption and handling time for the subsequent separation. With HTCC or XG alone, the harvest efficiency was consistently lower than 30%. The flocculation mechanism was investigated by changing the order in which the HTCC, XG, and Scenedesmus cells were added, and by fluorescence staining, scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The results showed that the mega flocs were formed by the crosslinking of HTCC and XG, based on their long-chain molecular structure and electrostatic interaction. Scenedesmus cells were enmeshed in the polymer matrix of HTCC and XG and then aggregated into large flocs. Thus, an effective, eco-friendly, and sustainable flocculation strategy for microalgae biomass was developed using the biodegradable components HTCC and XG.

Perfluorooctanoic acid (PFOA) is a persistent organic pollutant. This study established an in ovo peroxisome proliferator-activated receptor alpha (PPAR alpha) silencing model in chicken embryo heart, and investigated the role of PPAR alpha in PFOA induced developmental cardiotoxicity. The in ovo silencing was achieved by introducing lentivirus expressing PPAR alpha siRNA into ED2 chicken embryo via microinjection (0.05ul/g egg weight). Transfection efficacy was confirmed by fluorescent microscopy and western blotting. To assess the developmental cardiotoxicity, cardiac function (heart rate) and morphology (right ventricular wall thickness) were measured in D1 hatchling chickens. 2mg/kg (egg weight) PFOA exposure at ED0 induced significant elevation of heart rate and thinning of right ventricular wall thickness in D1 hatchling chickens. PPAR alpha silencing did not prevent PFOA-induced elevation of heart rate; however, it did significantly increase the right ventricular wall thickness as compared to PFOA exposed animals. Meanwhile, PPAR alpha silencing did not abolish the protective effects exerted by exposure to 100mg/kg (egg weight) l-carnitine. In conclusion, PFOA-induced heart rate elevation is likely PPAR alpha independent, while the right ventricular wall thinning seems to be PPAR alpha dependent. The protective effects of l-carnitine do not require PPAR alpha.

Occurrences of harmful cyanobacterial blooms are a worldwide environmental problem in most eutrophic lake ecosystems. But what should be noticed is that cyanobacteria can be used as a useful resource due to the wide range of metabolites they produce. Nutrient partitioning using purple nonsulfur bacteria (PNSB) has the potential to biologically concentrate nutrients. The present study evaluated the kinetics of nutrients released from decomposed field blue green algae (BGA) biomasses. The potential of nutrient acquisition from decomposed BGA biomasses for culturing Rhodopseudomonas palustris (R. palustris) was investigated via fed-batch experiments. Results indicated that R. palustris stimulated in algae substrates with algae biomasses ranging from 3.33 to 10 g/L. Removal efficiencies of N and P in the stationary phase of growth were at least 40% and 95%, respectively, of all the nitrogen (N) and phosphorus (P) released. Additionally, the cellular contents like total lipid and poly-beta-hydroxybutyrate (PHB), as well as the fatty acids produced by R. palustris, were consistent. Hence, practice based on the bacterial production for the nutrient recovery from BGA biomasses provides a new insight in field algae disposal. It will lower the chances of secondary pollution due to algae decay and produce giant cells of R. palustris and surely will prosper the industries applying R. palustris.

Cyanobacterial blooms are a major problem in many lakes and can negatively impact public health and ecosystem services. The bioflocculation technique has proven to be a cost-effective, environmentally friendly technique with no secondary pollution to harvest multiple microalgae; however, few studies have focused on its effect on and potential for controlling cyanobacterial blooms in eutrophic lakes. In this study, the bioflocculation efficiencies of different Microcystis species under Glyptotendipes tokunagai (Diptera, Chironomidae) stress conditions and the interactions between secreted silk from Chironomid larvae and extracellular polymeric substances (EPS) from Microcystis were compared. The results indicated that G. tokunagai presented better bioflocculation efficiency on M. wesenbergii than on M. aeruginosa. The formation of “Large Algal Aggregate” flocs was promoted by the derived-soluble extracellular polymeric substances (i.e., proteins and polysaccharides, sEPS) from M. wesenbergii and silk from G. tokunagai. Both M. wesenbergii and midge silk had abundant functional groups, which was beneficial to the formation of the large aggregate. G. tokunagai secreted a large amount of silk to bridge with the sEPS of M. wesenbergii, forming a network structure via interaction between filamentous substance (i.e., complex of sEPS and silk) that plays an important role in the aggregation of Microcystis and the removal of the Microcystis biomass in the water column. The findings provide further insights that will benefit the existing efforts of combating Microcystis blooms in the water column via bioflocculation and will provide a new sustainable approach for inhibiting early bloom formation from the perspective of its provenance in the sediment-water interface.

Flocculation-filtration treatment with cationic polymers and a rotary drum filter is an effective method to control Microcystis bloom by separating Microcystis from water. However, flocculation and corresponding removal are significantly affected by dissolved organic matters, of which extracellular organic matter (EOM) of Microcystis is the main source during Microcystis blooms. Hence, this study investigated the effect of EOM on the removal of Microcystis by using flocculation with cationic polyacrylamide (CPAM) and filtration with 100-μm filter. Results showed that the removal efficiency increased with the growth of Microcystis and was attributed to the accumulated EOM. With EOM > 2.5 mg/L extracted from stationary growth period, the cells could form large flocs with CPAM, over 90 % of which could be detained by a 100-μm sieve. Scanning electron microscope images showed that EOM interacted with CPAM and formed complexes, which bridged between the cells more strongly. Meanwhile, the removal was affected by EOM characteristics and had a positive correlation with the proportion of protein and polysaccharide in the EOM, which were usually regarded as polymers. The high-molecular weight (MW > 30 kDa) fraction was thus identified as an effective component in EOM to facilitate the formation of large and compact flocs, especially the fraction with MW > 100 kDa. This study partly revealed the differences in the removal efficiency of Microcystis from the perspective of the concentration and characteristic of EOM, and aid the understanding of the interaction between CPAM and high-MW EOM fraction for the formation of large and compact flocs.

Microcystis colonies can overwinter in sediment and may inoculate the water column through recruitment, promoting the annual recurrence of Microcystis blooms. Through microcosm experiments, the survivability of benthic Microcystis was quantitatively investigated by elucidating the dynamics of its cell numbers, photosynthetic activity, and toxin content under various sediment conditions. The abundance of Microcystis colonies in the sediment samples did not decrease significantly over the 22-week experiment at 5 °C, whereas more than 90% of the benthic population died within 3 months at 25 °C. The survivability of the Microcystis colonies under the aerobic conditions of surface sediments was significantly lower than under the anaerobic conditions of deep sediments. Toxic M. aeruginosa and non-toxic M. wesenbergii exhibited similar survivability, although the final survival efficiency of M. aeruginosa was higher than that of M. wesenbergii at 15 and 25 °C. Microcystin quotas remained stable at 5 and 15 °C but decreased significantly at 25 °C. The photosynthetic activity of the benthic Microcystis colonies decreased gradually, with a larger decline rate at higher temperatures. Our study suggests that most benthic Microcystis colonies can overwinter successfully, with microcystins preserved and photosynthetic activity maintained, significantly increasing the risk of bloom formation. However, they were unable to accumulate in the sediments of subtropical shallow lakes over a period of years.

Perfluorooctanoic acid (PFOA), a persistent organic pollutant, is associated with developmental toxicity. This study investigated the mechanism of PFOA-induced developmental cardiotoxicity in chicken embryo, focusing on the interactions between developmental exposure to PFOA and the levels of l-carnitine (LC), acetyl-l-carnitine (ALC) and propionyl-l-carnitine (PLC) in the heart. To evaluate the developmental cardiotoxicity, fertile chicken eggs were exposed to 0.1, 0.5, 1, 2 or 5mg/kg PFOA via air cell injection. Furthermore, exposure to 2mg/kg PFOA, with or without 100mg/kg LC were applied to investigate the effects of LC supplement. The results of functional and morphological assessments confirmed PFOA induced developmental cardiotoxicity in chicken embryo, which could be alleviated by co-exposure to LC. LC-MS/MS results also revealed remarkable decrease in LC, ALC and PLC levels in embryonic day six (ED6) chicken embryo hearts as well as LC level in embryonic day fifteen (ED15) chicken embryo hearts following developmental exposure to 2mg/kg PFOA. Meanwhile, co-exposure to 100mg/kg LC significantly elevated the levels of LC, ALC and PLC in chicken embryo hearts. Significantly elevated expression level of carnitine acetyltransferase (CRAT) in PFOA-exposed ED6 chicken embryo hearts was observed via western blotting, while LC co-exposure counteracted such changes. In conclusion, changes in the levels of LC, ALC and PLC in early embryonic stages are associated with PFOA induced developmental cardiotoxicity in chicken embryos.

Nuclear migration in Arabidopsis root hairs is bidirectional and relies on actin filaments. However, how actin filaments regulate the bidirectional movement of nuclei remains unclear. Here, we discovered that nuclei migrate forward and backward according to the developmental stage of the hair cells. In addition, the migration direction of nuclei was not constant but reversed occasionally, accompanied by nuclear shape changes. Confocal microscopic analysis revealed that perinuclear actin bundles were closely related to the migration and shape of hair cell nuclei. Pharmacological studies showed that SMIFH2, an inhibitor of the actin nucleator-formin, inhibited nuclear backward migration probably by impairing the perinuclear actin filaments. These data indicate that nuclear migration in hair cells is likely motivated by the competition of mechanical forces acting on the nucleus. Furthermore, the perinuclear actin filaments are closely related to the migration direction of hair cell nuclei.

The angiosperm pollen tube delivers two sperm cells into the embryo sac through a unique growth strategy, named tip growth, to accomplish fertilization. A great deal of experiments have demonstrated that actin bundles play a pivotal role in pollen tube tip growth. There are two distinct actin bundle populations in pollen tubes: the long, rather thick actin bundles in the shank and the short, highly dynamic bundles near the apex. With the development of imaging techniques over the last decade, great breakthroughs have been made in understanding the function of actin bundles in pollen tubes, especially short subapical actin bundles. Here, we tried to draw an overall picture of the architecture, functions and underlying regulation mechanism of actin bundles in plant pollen tubes.

The purpose of this study was to investigate the antiatherosclerosis effects of ursolic acid (UA) in high-fat diet-fed quails (Coturnix coturnix) and potential mechanism. Quails were treated with high-fat diet (14 % pork oil, 1 % cholesterol w/w) with or without UA (50, 150, or 300 mg/kg/day) for 10 weeks. Serum lipid profile was assessed at 0, 4.5, and 10 weeks. After 10 weeks, serum antioxidant status and morphology of aorta were assessed. Additionally, human umbilical vein endothelial cells (HUVECs) were exposed to 100 μg/ml oxidized low-density lipoprotein (ox-LDL) for 24 h, with or without pretreatment with UA (5, 10 or 20 μM) for 16 h, autophagy inhibitor 3-MA 5 mM for 2 h, or SIRT1 inhibitor EX-527 10 μM for 2 h. Cell viability and oxidative stress status were assessed and autophagy status was determined. Acetylation of lysine residue on Atg5 was assessed with immunoprecipitation. In results, high-fat diet negatively affected serum lipid profile and antioxidant status in quails and induced significant histological changes. Cotreatment with UA remarkably alleviated such changes. In HUVECs, ox-LDL treatment induced significant cytotoxicity along with oxidative stress, while UA cotreatment alleviated such changes significantly. UA treatment induced autophagy, enhanced SIRT1 expression, and decreased acetylation of lysine residue on Atg5. Cotreatment with 3-MA or EX-527 effectively abolished UA's protective effects. In summary, UA exerted antiatherosclerosis effects in quails and protected HUVECs from ox-LDL induced cytotoxicity, and the mechanism is associated with increased SIRT1 expression, decreased Atg5 acetylation on lysine residue, and increased autophagy.

In our previous study, l-carnitine was shown to have cytoprotective effect against hydrogen peroxide (H2O2)-induced injury in human normal HL7702 hepatocytes. The aim of this study was to investigate whether the protective effect of l-carnitine was associated with the nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2) pathway. Our results showed that pretreatment with l-carnitine augmented Nrf2 nuclear translocation, DNA binding activity and heme oxygenase-1 (HO-1) expression in H2O2-treated HL7702 cells, although l-carnitine treatment alone had no effect on them. Analysis using Nrf2 siRNA demonstrated that Nrf2 activation was involved in l-carnitine-induced HO-1 expression. In addition, l-carnitine-mediated protection against H2O2 toxicity was abrogated by Nrf2 siRNA, indicating the important role of Nrf2 in l-carnitine-induced cytoprotection. Further experiments revealed that l-carnitine pretreatment enhanced the phosphorylation of Akt in H2O2-treated cells. Blocking Akt pathway with inhibitor partly abrogated the protective effect of l-carnitine. Moreover, our finding demonstrated that the induction of Nrf2 translocation and HO-1 expression by l-carnitine directly correlated with the Akt pathway because Akt inhibitor showed inhibitory effects on the Nrf2 translocation and HO-1 expression. Altogether, these results demonstrate that l-carnitine protects HL7702 cells against H2O2-induced cell damage through Akt-mediated activation of Nrf2 signaling pathway.

A strain with efficient biofilm-formation and aerobic denitrification capabilities was isolated and identified as Pseudomonas mendocina IHB602. In pure culture, strain IHB602 removed almost all NO3−-N, NO2−-N, and NH4+-N (initial concentrations 50 mg/L) within 24 h. The strain produced large amounts of extracellular polymeric substances (maximum 430.33 mg/g cell dry weight) rich in protein but containing almost no humic acid. This, and strong autoaggregation (maximum 47.09%) and hydrophobicity (maximum 85.07%), imparted strain IHB602 with biofilm forming traits. A sequencing batch biofilm reactor bioaugmented with strain IHB602 (SBBR1) had more rapid biofilm-formation than the control without strain IHB602 inoculation (SBBR2). During the stabilization period, the effluent removal ratios for NH4+-N (95%), NO3−-N (91%) and TN (88%) in SBBR1 were significantly higher than those in SBBR2 (NH4+-N: 91%, NO3−-N: 88%, TN: 82%). Microbial community structure analysis revealed that strain IHB602 successfully proliferated and contributed to nitrogen removal as well as biofilm formation.

Integrative performance evaluation of constructed wetland in removal different aspects of bacteria under specific local environmental conditions needs to be explored in detail to ensure selection of appropriate and highly efficient macrophytes candidates. To achieve this, integrative purification performance evaluation approach that holistically considers all the aspects of pathogenic bacterial biology (colony numbers, functional gene, species, virulent, pathogenicity and resistant genes) needs to be adopted rather than the commonly known unidimensional approaches that take into account a single bacterial aspect. This study experimentally evaluated the individual performance of three native and one exotic winter tolerant submerged macrophytes combined with a single emergent macrophyte in eradicating faecal related bacterial species and pathotypes across horizontal surface flow constructed wetland. It involved the new multi-dimensional approach that integrated the faecal bacterial colony numbers, functional gene copies, species survival, virulent and pathogenicity as well as antimicrobial resistant in constructed wetland purification evaluation. The results showed Elodea nuttallii and Myriophyllum spicatum as the best candidate partners to Typha latifolia for the highest Purification Efficiency (P

The transcription factor sex determining region (Y SRY)-box 2 (SOX2) is known to play a crucial role in the maintenance of self renewal or pluripotency of undifferentiated embryonic and neuronal stem cells. An elevated expression of SOX2 has been correlated with poor prognosis of esophageal squamous cell carcinoma (ESCC). We sought to investigate the mechanism(s) by which SOX2 modulates the ESCC metastasis. The SOX2 coding DNA sequence was inserted into pCMV vector and stably transfected in ESCC cells (Eca-109). The effect of SOX2 over expression was evaluated on cell migration, invasion and epithelial to mesenchymal transition (EMT). We also measured the expression of Slug to explore if this transcription factor is involved in SOX2-mediated regulation of cell migration/invasion and EMT. In addition, we determined the role of STAT3/HIF-1α to further probe the mechanism of SOX2-mediated metastasis via Slug. Our results demonstrated that SOX2 over expressing Eca-109 cells showed an enhanced cell migration/invasion. Moreover, these cells exhibited the EMT characteristics, that is, a significantly suppressed expression of the epithelial cells marker with a concomitant enhancement of those of the mesenchymal markers. An increased expression of Slug in SOX2 over expressing cells suggested the involvement of this transcription factor in SOX2-regulated metastasis. Whereas the expressions of STAT3/HIF-1α were found to be up-regulated in SOX2 expressing cells, blockade of these transcription factors resulted in the inhibition of Slug expression at both protein and mRNA levels. Conclusion: These results suggest that SOX2 promoted the metastasis of ESCC, at least in part, by modulating Slug expression through the activation of STAT3/HIF-1α signaling.

l-Carnitine (LC) has protective effects on high glucose-induced oxidative stress in the retinal ganglion cells (RGCs). The aim of this study was to investigate the role of NF-E2-related factor 2 (Nrf2), Kelch like-ECH-associated protein 1 (Keap1), haemoxygenase-1 (HO-1) and γ-glutamyl cysteine synthetase (γ-GCS) in the protective effect of LC on RGCs. RGCs were first processed with high concentrations of glucose. LC treatment at three concentrations (50μM, 100μM and 200μM) was applied to high glucose stimulated RGCs. The expression of Nrf2, Keap1, haemoxygenase-1 (HO-1) and γ-glutamyl cysteine synthetase (γ-GCS) was quantified by Western blot in the treatment and control (high glucose stimulation) groups. In the three LC groups (50μM, 100μM and 200μM), Nrf-2 (0.71±0.04, 0.89±0.05, 1.24±0.05 vs 0.56±0.03, p

Radial oxygen loss (ROL) has been suggested to be a major process to protect plants exposed to the anaerobic by-products of soil anaerobiosis. The aim of the present study was to test the effects of root ROL from two submerged plants (Hydrilla verticillata and Vallisneria spiralis) on the rhizosphere oxygen profile and rhizosphere microarea. Phospholipid fatty acids (PLFAs) of sediment samples were used to characterize and quantify the microbial community. The results showed clearly that there were significant differences between the two plants in radial oxygen loss, which affected rhizosphere physicochemical parameters and the microbial community. Rhizosphere total biomass, bacteria, gram-positive bacteria, actinomycetes, and microbial diversity of V. spiralis were significantly higher than those of H. verticillata. The present study highlights root ROL as a key parameter affecting the microbial community of the rhizosphere microarea.

Habitat heterogeneity, physical barriers, and the uplift of the Yungui Plateau were found to deeply affect the phylogeographic pattern and evolutionary history of Cephalotaxus oliveri, a perennial conifer endemic to China. In this study, we explored the phylogeography using three chloroplast sequences (trnL-trnF, trnT-trnD and atpB-rbcL) in 22 natural populations of C. oliveri distributed throughout its range. The Yungui Plateau populations of C. oliveri were revealed to origin ca. 9.15Ma by molecular clock estimation, which is consistent with rapid uplift of the Qinghai-Tibetan Plateau (QTP) ca. 8-10Ma. Additionally, geological effects of the Yungui Plateau were suggested to promote the rapid intra-specific differentiation of C. oliveri in the Pliocene and Early Pleistocene. The relatively low level of genetic diversity (h=0.719, θ=1.17×10(-3)) and high population differentiation (NST=0.771 and GST=0.642) implied restricted gene flow among populations, which was confirmed by the Nested Clade Analysis (NCA). Mismatch distribution and haplotypes network provided evidences of recent demographic population expansion. Furthermore, the statistical dispersal-vicariance analysis indicated that the center of origin was in Central China. The comparison of haplotype distribution patterns indicated that the regions of HNHPS and HBLD were the potential refugia during the Pleistocene ice ages. Our results highlighted that habitat heterogeneity and physical barriers presenting in a species range can predict genetic patterns.

Perfluorooctanoic acid (PFOA) is an environmental contaminant that could induce developmental cardiotoxicity in a chicken embryo, which may be alleviated by l-carnitine. To explore the roles of reactive oxygen species (ROS) and nitric oxide (NO) in such changes and the potential effects of l-carnitine, fertile chicken eggs were exposed to PFOA via an air cell injection, with or without l-carnitine co-treatment. The ROS and NO levels in chicken embryo hearts were determined with electron spin resonance (ESR), and the protein levels of the nuclear factor κ-light chain-enhancer of activated B cells (NF-κB) p65 and inducible nitric oxide synthase (iNOS) in chicken embryo hearts were assessed with western blotting. The results of ESR indicated that PFOA exposure induced an elevation in the ROS levels in ED19 chicken embryo hearts and hatchling chicken hearts, while l-carnitine could alleviate such changes. Meanwhile, increased NO levels were observed in ED19 embryo hearts and hatchling hearts following PFOA exposure, while l-carnitine co-treatment exerted modulatory effects. Western blotting revealed that p65 translocation in ED19 embryo hearts and hatchling hearts was enhanced by PFOA, while l-carnitine co-treatment alleviated such changes. iNOS expression levels in ED19 embryo hearts followed the same pattern as NO levels, while a suppression of expression was observed in hatchling hearts exposed to PFOA. ROS/NF-κB p65 and iNOS/NO seem to be involved in the late stage (ED19 and post hatch) of PFOA-induced developmental cardiotoxicity in a chicken embryo. l-carnitine could exert anti-oxidant and NO modulatory effects in the developing chicken embryo hearts, which likely contribute to its cardioprotective effects.

Colony formation plays an important role in the life history of Microcystis. However, analyzing the colony size distribution with a microscope is time consuming, and colony formation also hinders the direct monitoring of cell density. In this study, a quantitative protocol for rapidly analyzing the cell density and colony size distribution of pelagic and benthic Microcystis was developed. Microcystis colonies were disintegrated by alkaline hydrolysis with 0.01-0.05 mol L-1 sodium hydroxide at 85 A degrees C for 6-8 min and automatically measured by the Flow Camera And Microscope (FlowCAM). Benthic Microcystis colonies were isolated from different lake sediments using 40 % Percoll solution. Alkaline hydrolysis was validated as a rapid and universally effective method to disintegrate different morphospecies of Microcystis colonies. The FlowCAM exhibited excellent accuracy, reproducibility, and efficiency in determining the cell density and size distribution of Microcystis. The developed protocol was successfully applied to field samples from Lake Caohai (China) and can accurately monitor the population dynamics and colony size distribution of bloom-forming Microcystis.

Pharmacological inhibition of histone deacetylases (HDACs) has been successfully applied in the treatment of a wide range of disorders, including Parkinson's disease, infection, cardiac diseases, inflammation, and especially cancer. HDAC inhibitors (HDACIs) have been proved to be effective antitumor agents by various stages of investigation. At present, there are two opposite focuses of HDACI design in the cancer therapy, highly selective inhibitor strategy and dual- or multitargeted inhibitors. The former method, which is supposed to elucidate the function of individual HDAC and provide candidate inhibitors with fewer side effects, has been widely accepted by the inhibitor developer. The latter approach, though less practiced, has promising potential for the antitumor therapy based on HDACIs. Effective HDACIs, some of which are in clinic anticancer research, have been developed by both methods. In order to gain insight into HDACI design, the strategies and achievements of the two diverse methods are reviewed.

Myocardin belongs to the SAF-A/B, Acinus, PIAS (SAP) domain family of transcription factors and is specifically expressed in cardiac and smooth muscle. Myocardin functions as a transcriptional coactivator of SRF and is sufficient and necessary for smooth muscle gene expression. We have previously found that myocardin induces the acetylation of nucleosomal histones surrounding SRF-binding sites in the control regions of cardiac and smooth muscle genes through recruiting chromatin-modifying enzyme p300, yet no studies have determined whether myocardin itself is similarly modified. In this study, we show that myocardin is a direct target for p300-mediated acetylation. p300 acetylates lysine residues at the N terminus of the myocardin protein. Interestingly, a direct interaction between p300 and myocardin, which is mediated by the C terminus of myocardin, is required for the acetylation event. Acetylation of myocardin by p300 enhances the association of myocardin and SRF as well as the formation of the myocardin-SRF-CArG box ternary complex. Conversely, acetylation of myocardin decreases the binding of histone deacetylase 5 (HDAC5) to myocardin. Acetylation of myocardin is required for myocardin to activate smooth muscle genes. Our study demonstrates that acetylation plays a key role in modulating myocardin function in controlling cardiac and smooth muscle gene expression.

Adenylyl cyclase type 5 knockout mice (AC5 KO) live longer and are stress resistant, similar to calorie restriction (CR). AC5 KO mice eat more, but actually weigh less and accumulate less fat compared to WT mice. CR applied to AC5 KO result in rapid decrease in body weight, metabolic deterioration and death. These data suggest that despite restricted food intake in CR, but augmented food intake in AC5 KO, the two models affect longevity and metabolism similarly. To determine shared molecular mechanisms, mRNA expression was examined genome-wide for brain, heart, skeletal muscle and liver. Significantly more genes were regulated commonly rather than oppositely in all the tissues in both models, indicating commonality between AC5 KO and CR. Gene Ontology analysis identified many significantly regulated, tissue-specific pathways shared by the two models, including sensory perception in heart and brain, muscle function in skeletal muscle, and lipid metabolism in liver. Moreover, when comparing gene expression changes in the heart under stress, the glutathione regulatory pathway was consistently upregulated in the longevity models but downregulated with stress. In addition, AC5 and CR shared changes in genes and proteins involved in the regulation of longevity and stress resistance, including Sirt1, ApoD and olfactory receptors in both young and intermediate age mice. Thus, the similarly regulated genes and pathways in AC5 KO and CR, particularly related to the metabolic phenotype, suggest a unified theory for longevity and stress resistance.

Two fundamental questions on how invasive species are able to rapidly colonize novel habitat have emerged. One asks whether a negative correlation exists between the genetic diversity of invasive populations and their geographic distance from the origin of introduction. The other is whether selection on the chloroplast genome is important driver of adaptation to novel soil environments. Here, we addressed these questions in a study of the noxious invasive weed, Mikania micrantha, which has rapidly expanded in to southern China after being introduced to Hong Kong in 1884. Seven chloroplast simple sequence repeats (cpSSRs) were used to investigate population genetics in 28 populations of M. micrantha, which produced 39 loci. The soil compositions for these populations, including Mg abundance, were measured. The results showed that M. micrantha possessed relatively high cpSSR variation and differentiation among populations. Multiple diversity indices were quantified, and none was significantly correlated with distance from the origin of introduction. No evidence for “isolation by distance,” significant spatial structure, bottlenecks, nor linkage disequilibrium was detected. We also were unable to identify loci on the chloroplast genome that exhibited patterns of differentiation that would suggest adaptive evolution in response to soil attributes. Soil Mg had only a genome-wide effect instead of being a selective factor, which highlighted the association between Mg and the successful invasion. This study characterizes the role of the chloroplast genome of M. micrantha during its recent invasion of southern China.

Ca2+ mobilization from intracellular stores represents an important cell signalling process that is regulated, in mammalian cells, by inositol-1,4,5-trisphosphate (InsP3), cyclic ADP ribose and nicotinic acid adenine dinucleotide phosphate (NAADP). InsP3 and cyclic ADP ribose cause the release of Ca2+ from sarcoplasmic/endoplasmic reticulum stores by the activation of InsP3 and ryanodine receptors (InsP3Rs and RyRs). In contrast, the nature of the intracellular stores targeted by NAADP and the molecular identity of the NAADP receptors remain controversial, although evidence indicates that NAADP mobilizes Ca2+ from lysosome-related acidic compartments. Here we show that two-pore channels (TPCs) comprise a family of NAADP receptors, with human TPC1 (also known as TPCN1) and chicken TPC3 (TPCN3) being expressed on endosomal membranes, and human TPC2 (TPCN2) on lysosomal membranes when expressed in HEK293 cells. Membranes enriched with TPC2 show high affinity NAADP binding, and TPC2 underpins NAADP-induced Ca2+ release from lysosome-related stores that is subsequently amplified by Ca2+-induced Ca2+ release by InsP3Rs. Responses to NAADP were abolished by disrupting the lysosomal proton gradient and by ablating TPC2 expression, but were only attenuated by depleting endoplasmic reticulum Ca2+ stores or by blocking InsP3Rs. Thus, TPCs form NAADP receptors that release Ca2+ from acidic organelles, which can trigger further Ca2+ signals via sarcoplasmic/endoplasmic reticulum. TPCs therefore provide new insights into the regulation and organization of Ca2+ signals in animal cells, and will advance our understanding of the physiological role of NAADP.

To analyze the relation between SNPs in DNA repair pathway-related genes and sensitivity of tumor radio-chemotherapy, 26 SNPs in 20 DNA repair genes were genotyped on 176 patients of NSCLC undertaking radio-chemotherapy treatment. In squamous cell carcinoma (SCC), as the rs2228000, rs2228001 (XPC), rs2273953 (TP73), rs2279744 (MDM2), rs2299939 (PTEN) and rs8178085, rs12334811 (DNA-PKcs) affected the sensitivity to chemotherapy, so did the rs8178085, rs12334811 to radiotherapy. Moreover rs344781, rs2273953 and rs12334811 were related with the survival time of SCC. In general, the “good” genotype GG (rs12334811) showed greater efficacy of radio-chemotherapy and MSF (24 months) on SCC. In adenocarcinoma, as the rs2699887 (PIK3), rs12334811 (DNA-PKcs) influenced the sensitivity to chemotherapy, so did the rs2299939, rs2735343 (PTEN) to radiotherapy. And rs402710, rs80270, rs2279744 and rs2909430 impacted the survival time of the adenocarcinoma patients. Both GG (rs2279744) and AG (rs2909430) showed a shorter survival time (MFS = 6). Additionally, some SNPs such as rs2228000, rs2228001 and rs344781 were found to regulate the expression of DNA repair pathway genes through eQTLs dataset analysis. These results indicate that SNPs in DNA repair pathway genes might regulate the expression and affect the DNA damage repair, and thereby impact the efficacy of radio-chemotherapy and the survival time of NSCLC.

The indoles plant growth hormones have exhibited potentially antitumor activities. However, the targets of these indoles have not been clearly elucidated. By introduction of hydroxamic acid group to the structure of indolebutyric acid, the derived molecule (IBHA) exhibited potent HDAC2 (IC50 value of 0.32 ± 0.02 µM) and HDAC3 (IC50 value of 0.14 ± 0.01 µM) inhibitory activities compared with SAHA (IC50 value of 1.25 ± 0.06 µM and 0.97 ± 0.04 µM against HDAC2 and HDAC3). In the antiproliferative assays, the tested hematologic cell lines (U937 and K562) are more sensitive to IBHA than the solid tumor cell lines (MDA-MB-231 and PC-3). In the docking studies, the derived molecule (IBHA) could bind to the active site of human HDAC2 and HDAC3 by strong H-bond interactions and hydrophobic interactions. Pharmacophore mapping results revealed that properties of IBHA matches the receptor (HDAC3) based pharmacophore model.

The aim of this study is to assess the potential protective effect of oleanolic acid (OA) against ox-LDL induced damage in human umbilical vascular endothelial cells (HUVECs) and investigate potential mechanism of action including antioxidative effects and inhibition of mitochondria apoptosis pathway. Cell counting kit 8 was used to evaluate the viability of HUVECs. 2', 7'-DCFH-DA staining and flow cytometry was used to assess the levels of intracellular reactive oxygen species in HUVECs. The protein expression levels of uncoupling protein 2, cytochrome C, and apoptosis induction factors were measured by western blotting. The results indicated that OA treatment alleviated ox-LDL induced cytotoxicity in HUVECs and ameliorated the reactive oxygen species levels. Western blotting results demonstrated that OA treatment increased the expression level of uncoupling protein 2 and decreased the release of cytochrome C and apoptosis induction factors from mitochondria to cytoplasm, suggesting inhibition of mitochondria apoptosis pathway. In conclusion, OA could protect HUVECs from ox-LDL-induced cytotoxicity; its antioxidant property and inhibition of mitochondria apoptosis are likely crucial contributors.

Microcystin-LR (MCLR) and linear alkylbenzene sulfonate (LAS) are commonly found in eutrophic lakes due to toxic cyanobacterial blooms and exogenous organic compounds pollution. However, the ecotoxicological risk of their combination in the aquatic environment is unknown. This study investigated the effects of MCLR. LAS and their mixture on duckweed (Lemna minor) growth and physiological responses. MCLR accumulation in duckweed, with or without LAS, was also examined. Growth of duckweed and chlorophyll-a contents were significantly reduced after 8d exposure to high concentrations of MCLR (>= 3 mu g/ml), LAS (>= 20 mu g/ml) and their mixture (>= 3 + 10 mu g/ml). After 2 d of exposure, superoxide dismutase activity and glutathione content in duckweed increased with increasing concentrations of MCLR, LAS and their mixture, with a significant difference observable after 8 d of exposure. When MCLR and LAS concentrations were lower (

This study focused on the anti-proliferation effects of ursolic acid (UA) in rat primary vascular smooth muscle cells (VSMCs) and investigated underlying molecular mechanism of action. Rat primary VSMCs were pretreated with UA (10, 20 or 30μM) or amino guanidine (AG, 50μM) for 12h or with PI3K inhibitor LY294002 for 30min or with Akt inhibitor MK2206 for 24h, then 10% fetal bovine serum was used to induce proliferation. CCK-8 was used to assess cell proliferation. To explore the mechanism, cells were treated with UA (10, 20 or 30μM), LY294002 or MK2206, or transient transfected to inhibit miRNA-21 (miRNA-21) or to overexpress PTEN, then quantitative real-time PCR was used to assess the mRNA levels of miRNA-21 and phosphatase and tensin homolog (PTEN) for cells treated with UA or miRNA-21 inhibitor; western blotting was used to measure the protein levels of PTEN and PI3K. UA exerted significant anti-proliferation effects in rat primary VSMCs. Furthermore, UA inhibited the expression of miRNA-21 and subsequently enhanced the expression of PTEN. PTEN was found to inhibit the expression of PI3K. In conclusion, UA exerts anti-proliferation effects in rat primary VSMCs, which is associated with the inhibition of miRNA-21 expression and modulation of PTEN/PI3K signaling pathway.

Background This study was designed to evaluate the protective effects of Arctium lappa L. root extracts (AREs) from different extraction methods (aqueous, ethanol, chloroform and flavone) on atherosclerosis. Methods Quails (Coturnix coturnix) were subjected to high fat diet, with or without one of the four different AREs or positive control simvastatin. Blood samples were collected before treatment, after 4.5 weeks or ten weeks to assess lipid profile (Levels of total cholesterol (TC), Triacylglycerol (TG), low-density lipoprotein (LDL) and high-density lipoprotein (HDL)). After ten weeks, the serum levels of nitric oxide (NO) as well as antioxidant and pro-oxidative status (Levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione peroxidase (GSH-Px)) were measured. Furthermore, aortas were collected after ten weeks treatment, aorta lipid contents (TC, TG and LDL) were assessed, and histology was used to confirm atherosclerotic changes. Results The results indicated that high fat diet significantly deteriorated lipid profile and antioxidant status in quail serum, while all the extracts significantly reverted the changes similar to simvastatin. Aorta lipid profile assessment revealed similar results. Histology on aortas from quails treated for ten weeks confirmed atherosclerotic changes in high fat diet group, while the extracts significantly alleviated the atherosclerotic changes similar to simvastatin. Among the different extracts, flavones fraction exerted best protective effects. Conclusions Our data suggest that the protective effects of AREs were medicated via hypolipidemic and anti-oxidant effects. Underlying molecular mechanisms are under investigation.

Premise of the study: To survey population variation and the adaptive evolution of Cephalotaxus fortunei (Cephalotaxaceae), an endemic and endangered conifer in China, microsatellite markers were developed and characterized for this species. Methods and Results: Based on the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol, 15 microsatellite markers were developed for C. fortunei, 13 of which were polymorphic within a sample of 75 individuals representing five natural populations. The number of alleles per locus ranged from one to seven. The expected and observed heterozygosities were 0.108–0.738 and 0.000–1.000, respectively. Ten polymorphic loci were also successfully amplified in C. oliveri. Conclusions: These polymorphic loci provide a valuable tool for population genetic analysis of C. fortunei, which will contribute to its management and conservation.

4-N-trimethylammonium-3-hydroxybutyric acid (L-carnitine) is an endogenous mitochondrial membrane compound and some studies have reported that L-carnitine could effectively protect various cells against oxidative injury both in vitro and in vivo. In the present study, we used the human neuroblastoma SH-SY5Y cell line as an in vitro model and assessed the effect of L-carnitine on hydrogen peroxide (H(2)O(2))-mediated oxidative stress and neurotoxicity.Cells in culture were treated with different concentrations of H(2)O(2) alone or pretreated with L-carnitine. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, transmission electron microscopy, agarose gel electrophoresis, biochemical methods, and Western blotting were employed in the present study.Pretreatment with L-carnitine for 3 hours inhibited H(2)O(2)-induced cell viability loss, morphological changes, intracellular reactive oxygen species generation, and lipid peroxidation in a concentration-dependent manner. Endogenous anti-oxidant defense components including total anti-oxidative capacity, glutathione peroxidase, catalase, and superoxide dismutase were also promoted by L-carnitine. Meanwhile, H(2)O(2)-induced down-regulation of Bcl-2, up-regulation of Bax, and DNA damage and apoptosis were also inhibited in the presence of L-carnitine.Taken together, these results suggest that L-carnitine may function as an anti-oxidant to inhibit H(2)O(2)-induced oxidative stress as well as regulation of Bcl-2 family and prevent the apoptotic death of neuronal cells, which might be beneficial for the treatment of oxidative stress in neurodegenerative diseases.

Aims: Purple sweet potato (PSP) pigments were proved to protect murine thymocytes from 60Co γ-ray-induced mitochondria-mediated apoptosis in our previous study. In this study, we further investigated the effect of PSP pigments on apoptosis related ROS, p53 and Bcl-2 family. Methods: Cell viability was analyzed by MTT. Apoptosis was certified by DNA ladder detection. Reactive oxygen species (ROS) were detected using 2',7',- dichlorofluorescein diacetate (DCFH-DA) probe. P53, Bcl-2 and Bax proteins were analyzed by western blot. The activities of caspase-3 and caspase-9 were determined by fluorogenic substrates detection. Results: PSP pigments treatment prior to 4Gy 60Co γ-ray irradiation increased the cell viability and decrease the apoptosis. In the presence of PSP pigments, ROS was scavenged and followed by a p53-depression. A shift in Bcl-2/Bax ratio towards anti-apoptosis was observed as a result of p53-depression. The activities of caspase-9 and caspase-3 were reduced by PSP pigments pretreatment. Conclusions: PSP pigments have a cytoprotective activity against γ radiation. The protective effect of PSP pigments may be involving ROS scavenging, p53 depression and Bcl-2/Bax modulation in a caspase-dependent mitochondrial way.

Purpose: Purple sweet potato (PSP) pigments have been widely accepted as antioxidants but their radioprotective effect still remains unclear. In this study we investigated the effect of PSP pigment...

This study was designed to investigate the effect and molecular mechanisms of Haishengsu (HSS), a protein extract from a shellfish Tegillarca granosaL., on a drug resistant leukemia cell line. Cultured K562/Adriamycin (ADM) cells were treated with HSS at 10, 20 and 40 microg/mL, respectively. The apoptosis and expression of p-glycoprotein was evaluated by flow cytometry. Expressions of caspase-3 and Bcl-2 were also evaluated. There was a significant dose-dependent increase in the apoptosis in the HSS treated K562/ADM cells (P0.05 and 0.01, respectively). The p-glycoprotein expression in the 40 microg/mL HSS group (14.8%) was lower than in the control (16.9%, P0.05) and the 10 microg/mL HSS group (7.3%, P0.05), but it was similar to the HSS 20 microg/mL group (10.7%, P0.05). The expressions of apoptosis-stimulating protein caspase-3 protein were increased, whereas the expressions of apoptosis-suppressing Bcl-2 were decreased in the HSS groups, as compared with the levels in the control group (P0.05). We conclude that HSS induces apoptosis of the Adriamycin-resistant K562/ADM cells. The enhanced expressions in caspase-3 and the reduced expressions in Bcl-2 protein may have contributed to the apoptosis-stimulating effect of HSS. The inhibition of p-glycoprotein suggests that HSS may diminish the resistance to Adriamycin and potentially enhance the therapeutic effects.

We extracted marine low-temperature lysozyme (MLTL), a novel lysozyme, from a marine microorganism through fermentation. Our previous study suggested that a low molecular weight (16 kDa) may exert anti-tumor activity through antiangiogenesis. In this study, we extracted a high weight (39 kDa) and investigated its antiangiogenic activity in vivo and in vitro. Using zebrafish embryos as an in vivo study model, we found that treatment with MLTL significantly inhibited the growth of subintestinal vessels (SIVs) in a dose-dependent manner and that 400 µg/ml MLTL was sufficient to block the growth of SIVs. An in vitro study conducted using human umbilical vein endothelial cells (HUVECs) revealed that MLTL suppressed the proliferation, migration and tube formation of HUVECs in a dose-dependent manner. Interestingly, assays by flow cytometry and DNA electrophoresis indicated that MLTL was able to induce apoptosis of HUVECs. Moreover, further study demonstrated that the disruption of intracellular Ca2+ homeostasis may play an important role in MLTL induced apoptosis of HUVECs. Taken together, the results of this study demonstrate for the first time that MLTL inhibits angiogenesis through its pleiotropic effects on vascular endothelial cells and induces apoptosis through regulation of cellular Ca2+ levels. The results of this study also revealed a possible mechanism underlying the antiangiogenic effect of MLTL and suggested that MLTL may be a promising new antiangiogenic agent for use in cancer therapy.

Oxidative stress has long been linked to cell death in many neurodegenerative conditions. Treatment with antioxidants is a promising approach for slowing disease progression. In this study, we used the neuroblastoma SH-SY5Y cells as an in vitro model to first assess the effect of polypeptide from Chlamys farreri (PCF), a natural marine antioxidant, on H2O2-induced neuronal cell death. Pre-treatment of SH-SY5Y cells with PCF inhibited H2O2-induced cell death in a concentration-dependent manner. In parallel, intracellular reactive oxygen species generation and lipid peroxidation were inhibited by PCF. Under severe H2O2 insult, PCF promoted endogenous antioxidant defense components including glutathione peroxidase, catalase, superoxide dismutase, and glutathione. PCF also protected DNA from oxidative damage and enhanced the removal of 8-oxo-7,8-dihydro-2′-deoxyguanosine from DNA. Further, we found that PCF potentially prevented H2O2–induced cell apoptosis. When investigated mitogen-activated protein kinase signaling pathway, we found that pre-treatment of cells with PCF significantly blocked H2O2–induced phosphorylation of c-Jun N-terminal kinase of the mitogen-activated protein kinase family. However, PCF had little inhibitory effect on the H2O2–induced activation of extracellular signal-regulated kinase. Taken together, these data demonstrate that PCF prevents oxidative stress-induced reactive oxygen species production and c-Jun N-terminal kinase activation and may be useful in the treatment of neurodegenerative diseases.