[Regulation of intracellular level of ATP and NADH in Escherichia coli to promote succinic acid production].

Succinic acid is an important C4 platform chemical that is widely used in food, chemical, medicine sectors. The bottleneck of fermentative production of succinic acid by engineered Escherichia coli is the imbalance of intracellular cofactors, which often leads to accumulation of by-products, lower yield and low productivity. Stoichiometric analysis indicated that an efficient production of succinic acid by E. coli FMME-N-26 under micro-aeration conditions might be achieved when the TCA cycle provides enough ATP and NADH for the r-TCA pathway. In order to promote succinic acid production, a serial of metabolic engineering strategies include reducing ATP consumption, strengthening ATP synthesis, blocking NADH competitive pathway and constructing NADH complementary pathway were developed. As result, an engineered E. coli FW-17 capable of producing 139.52 g/L succinic acid and 1.40 g/L acetic acid in 5 L fermenter, which were 17.81% higher and 67.59% lower than that of the control strain, was developed. Further scale-up experiments were carried out in a 1 000 L fermenter, and the titer of succinic acid and acetic acid were 140.2 g/L and 1.38 g/L, respectively.

Gancao Nourishing-Yin decoction combined with methotrexate in treatment of aging CIA mice: a study based on DIA proteomic analysis.

BACKGROUND: Elderly rheumatoid arthritis (ERA) population faces multiple treatment dilemma. Here we aim to investigate if Gancao Nourishing-Yin decoction (GCNY) added to methotrexate (MTX) exhibit better effects in an ERA mice model. METHODS: ERA mice model was established by adding D-galactose (Dgal) to collagen-induced arthritis (CIA) mice. The model was then assigned into control group (CIA + Dgal), MTX treatment group (MTX), GCNY treatment group (GCNY), and integrative treatment group (MTX + GCNY). Pathological scoring was performed to evaluate the severity between the groups. Proteomic analysis was applied to investigate the secretory phenotype of the ERA mouse model and the underlying mechanism of GCNY, MTX and their combination. Representative cytokines related to proteomic results were further validated by ELISAs. RESULTS: CIA + Dgal mice showed more aggressive joints damage than the CIA mice. Besides changes in the inflammatory pathway such as Pi3k-Akt signaling pathway in both model, differential expressed proteins (DEPs) indicated metabolism-related pathways were more obvious in CIA + Dgal mice. Low-dose MTX failed to show pathological improvement in CIA + Dgal mice, while GCNY improved joints damage significantly. Besides down-regulated inflammation-related targets, GCNY-regulated DEPs (such as Apoc1 ~ 3, Grk2 and Creb3l3) were broadly enriched in metabolism-related pathways. MTX + GCNY showed the best therapeutic effect, and the DEPs enriched in a variety of inflammatory,metabolism and osteoclast differentiation signaling pathway. Notably, MTX + GCNY treatment up-regulated Dhfr, Cbr1, Shmt1 involved in folic acid biosynthesis and anti-folate resistance pathways indicated a coincidence synergic action. ELISAs confirmed CPR and Akt that elevated in CIA + Dgal mice were significantly ameliorated by treatments, and adding on GCNY elevated folic acid levels and its regulator Dhfr. CONCLUSION: Aging aggravated joints damage in CIA, which probably due to metabolic changes rather than more severe inflammation. GCNY showed significant effects in the ERA mice model especially when integrated with MTX to obtain a synergic action.

Black ginseng protects against Western diet-induced nonalcoholic steatohepatitis by modulating the TLR4/NF-κB signaling pathway in mice.

Black ginseng (BG) shows beneficial effects on liver injury, but the related mechanism has not been fully revealed. This study attempted to investigate the protective effects and associated mechanisms of BG against nonalcoholic steatohepatitis (NASH). Twelve ginsenosides in BG were annotated by ultrahigh performance liquid chromatography combined with high resolution mass spectrometry (UHPLC-HRMS). The Western diet (WD) together with the low-dose CCl4 was given to mice to create the NASH model. Histopathological examination and liver/serum biochemical analysis revealed that the NASH mice displayed severe steatosis and liver damage compared with control mice. After BG administration, the serum and liver triglycerides (TG) concentrations and the serum level of low-density lipoprotein (LDL) were dramatically reduced. Besides, the BG treatment greatly decreased the serum values of interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α), and the hepatic expression of fibrotic-related genes, such as alpha-smooth muscle actin (α-SMA) and collagen type I alpha 1 (Col1α1). We further discovered that BG administration could block the protein expression of toll-like receptor 4 (TLR4) and the phosphorylation of nuclear factor-kappa B p65 (NF-κB p65), indicating that BG exerted a liver protective effect via regulating the TLR4/NF-κB pathway. This study demonstrated the therapeutic efficacy and the associated mechanism of BG in the treatment of NASH, giving evidence for BG as a potential functional food to prevent NASH. PRACTICAL APPLICATIONS: BG is a type of processed ginseng product that has been used as diet supplementation and has shown favorable effects on liver injury. However, the pharmacological impact of BG on NASH has not been studied in depth. The present study showed that BG could effectively reduce WD-induced liver fibrosis and inflammation through the TLR4/NF-κB axis, which indicated that BG has the potential to be utilized as a functional herb to attenuate liver injury.

Exploring the Therapeutic Effects of Black Ginseng on Non-Alcoholic Fatty Liver Disease by Using Network Pharmacology and Molecular Docking.

This study aimed to investigate the therapeutic effect of black ginseng (BG) on non-alcoholic fatty liver disease (NAFLD) using network pharmacology combined with the molecular docking strategy. The saponin composition of BG was analyzed by liquid chromatography-mass spectrometry (LC/MS) instrument. Then the network pharmacology was applied to explore the potential targets and related mechanisms of BG in the treatment of NAFLD. After screening out key targets, molecular docking was used to predict the binding modes between ginsenoside and target. Finally, a methionine and choline deficiency (MCD) diet-induced NAFLD mice model was established to further confirm the therapeutic effect of BG on NAFLD. Twenty-four ginsenosides were annotated based on the MS and tandem MS information. Ten proteins were screened out as key targets closely related to BG treatment of NAFLD. The molecular docking showed that most of the ginsenosides had good binding affinities with AKT1. The validation experiment revealed that BG administration could reduce serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and improve the MCD diet-induced histological changes in liver tissue. Moreover, BG could upregulate the phosphorylation level of AKT in the liver of NAFLD mice, thereby exerting the therapeutic effect on NAFLD. Further studies on the active ginsenosides as well as their synergistic action on NAFLD will be required to reveal the underlying mechanisms in-depth. This study demonstrates that network pharmacological prediction in conjunction with molecular docking is a viable technique for screening the active chemicals and related targets of BG, which can be applied to other herbal medicines.

[Correlation of gut microbiota and ischemic stroke: a review].

With the widespread application of next-generation sequencing(NGS), especially 16 S rRNA and shotgun sequencing, researchers are no longer troubled with massive data on the gut microbiota, and the correlation between the gut microbiota and the brain(central nervous system) has been gradually revealed. Research on the microbiota-gut-brain axis(MGBA) based on the gut microbiota have provided insights into the exploration of the pathogenesis and risk factors of ischemic stroke(IS), a cerebrovascular disease with high disability and mortality rates, and also facilitate the selection of therapeutic targets of this class of drugs. This study reviewed the application of NGS in the study of gut microbiota and the research progress of MGBA in recent years and systematically collated the research papers on the correlation between IS and gut microbiota. Furthermore, from the bi-directional regulation of MGBA, this study also discussed the high-risk factors of IS under the dysregulation of gut microbiota and the pathophysiological changes of gut microbiota after the occurrence of IS and summarized the related targets to provide a reliable reference for the therapeutic research of IS from the gut microbiota.

Antifibrotic Effects of Kangxian Ruangan Capsule on Rats with Nonalcoholic Fatty Liver Fibrosis and Hepatic Stellate Cells through Regulation of TGF-ß and TLR4 Signaling Pathways.

Kangxian ruangan (KXRG) is a traditional Chinese medicine (TCM) formula consisting of 12 herbs. TCM syndrome differentiation proposes that KXRG exerts pharmacological effects against nonalcoholic fatty liver disease (NAFLD) fibrosis. This work investigates the effect of KXRG on NAFLD fibrosis in vivo and in vitro. In vivo, the NAFLD fibrosis model was constructed in Wistar rats using methionine- and choline-deficient (MCD) diet, followed by KXRG (0.92 g/kg/d) treatment for 8 weeks. In vitro, primary hepatic stellate cells (HSCs) were activated using platelet-derived growth factor (PDGF) and treated with KXRG. Molecular mechanisms underlying fibrosis were investigated. After 8 weeks, compared with the control groups, the histological lesions, degree of fibrosis, and inflammatory reaction increased with the MCD diet as demonstrated by histological changes and increased fibrosis-related (α-SMA, TGF-ß, COL1A1, and desmin, P < 0.01) and inflammation-related factors (TNF-α, MCP-1, and F4/80, P < 0.01), whereas they decreased with KXRG treatment (P < 0.01). KXRG not only inhibited the proliferation of activated HSCs and promoted their apoptosis but also resulted in G0-G1 arrest. Furthermore, KXRG suppressed HSC activation (P < 0.01), collagen synthesis (P < 0.01), and α-SMA expression (P < 0.01) with PDGF stimulation. In both the MCD diet-induced animal model and PDGF-induced cell model, KXRG inhibited TGF-ß and TLR4 signaling (P < 0.01), similar to corresponding small-molecule inhibitors. These results demonstrated that KXRG might exert suppressive effects against NAFLD fibrosis via regulating TGF-ß and TLR4 signaling. KXRG may act as a natural and potent therapeutic agent against NAFLD.

Traditional Chinese medicine for gouty arthritis: A protocol for meta-analysis.

BACKGROUND: Gouty arthritis (GA) is a chronic disease caused by monosodium urate crystal deposition. Repeated attacks of arthritis may lead to the deposition of urate to form gout stone, resulting in joint deformity and joint damage. Although GA is not fatal, it causes low work productivity and low quality of life. Western drug, such as febuxostat, colchicine, allopurinol, often cannot get satisfying curative effect, and may even lead to serious side effects, such as exfoliative dermatitis or uremia. However, the therapeutic effect of Traditional Chinese medicine is very satisfactory. The treatment effect of simiao powder, a Chinese patent medicine, combined with acupuncture was widely used on treatment of GA. Although it has been widely used in clinical practice, its relative effectiveness and safety have not been confirmed. Therefore, this study will use meta-analysis to verify the efficacy and safety of simiao powder combined with acupuncture in the treatment of GA. METHODS: All randomized controlled trial of simiao powder combined with acupuncture for the treatment of RA from their inception 29 October, 2020 will be searched form the China National Knowledge Infrastructure, Wanfang Database, Chinese Science and Technology Periodical Database, Chinese Biomedical Literature Database, Pubmed, Embase, Web of Science, and the Cochrane library. Two authors will independently select studies, extract data based on pre-designed inclusion and exclusion criteria. Methodological quality assessment and risk of bias will be assessed using Cochrane bias risk tool. All data analysis will be conducted using Revman5.3, WinBUGS 1.4.3, and Stata14.2 software. RESULTS: We will compare the different outcome indicators of various studies to provide a synthesis of the efficacy and safety of Simiao powder combined with acupuncture for GA patients. The main outcome measures included efficacy, remission rate (no drug symptoms), recurrence rate, clinical absolute score and relative score. Secondary outcome measures included related adverse reactions and uric acid concentration. CONCLUSION: The findings of the study will provide helpful evidence for the efficacy and safety of simiao powder combined with acupuncture in the treatment of GA. REGISTRATION NUMBER: This study protocol have been funded through a protocol registry. The registry number is INPLASY2020110028.

Compound Fu brick tea modifies the intestinal microbiome composition in high-fat diet-induced obesity mice.

Compound Fu Brick Tea (CFBT), which is from Duyun city in China, is a traditional Chinese dark tea, Fu Brick Tea, mixed with six herbal medicine. It is consumed by local people for reducing weight, but the mechanism is not clear. The disorder of intestinal microbiome caused by long-term high-fat diet (HFD) is one of the inducements of obesity and related metabolic syndrome. In this study, mice were fed with HFD to establish a high-fat model. Fifty mice were randomly divided into six groups: normal control (CK), HFD model control (NK), positive control with medicine (YK), CFBT groups with low, middle, and high dose (FL, FM, FH). The V3-V4 DNA region of fecal microbiome from mouse intestine was sequenced. The results showed that the diversity of intestinal microflora was highest in CK and lowest in NK. Compared with CK, the dominant bacterium Firmicutes was increased and Bacteroidetes decreased at phylum level in NK. Compared with NK, the abundance of microbiome in CFBT groups was significantly higher and the composition was changed: Muribaculaceae, Bacteroidaceae, and Prevotellaceae increased and Lachnospiraceae decreased in CFBT groups at family level, while at the genus level, Bacteroides increased and Lactobacillus decreased. These results conclude that CFBT can increase the abundance of intestinal microbiome in mice, promote the growth of beneficial bacteria and reduce the number of pathogenic bacteria, and restore the imbalance of intestinal microbiome caused by poor diet.

Mechanism of Dayuanyin in the treatment of coronavirus disease 2019 based on network pharmacology and molecular docking.

BACKGROUND: At present, coronavirus disease 2019 (COVID-19), caused by infection with severe acute respiratory syndrome coronavirus 2, is spreading all over the world, with disastrous consequences for people of all countries. The traditional Chinese medicine prescription Dayuanyin (DYY), a classic prescription for the treatment of plague, has shown significant effects in the treatment of COVID-19. However, its specific mechanism of action has not yet been clarified. This study aims to explore the mechanism of action of DYY in the treatment of COVID-19 with the hope of providing a theoretical basis for its clinical application. METHODS: First, the TCMSP database was searched to screen the active ingredients and corresponding target genes of the DYY prescription and to further identify the core compounds in the active ingredient. Simultaneously, the Genecards database was searched to identify targets related to COVID-19. Then, the STRING database was applied to analyse protein-protein interaction, and Cytoscape software was used to draw a network diagram. The R language and DAVID database were used to analyse GO biological processes and KEGG pathway enrichment. Second, AutoDock Vina and other software were used for molecular docking of core targets and core compounds. Finally, before and after application of DYY, the core target gene IL6 of COVID-19 patients was detected by ELISA to validate the clinical effects. RESULTS: First, 174 compounds, 7053 target genes of DYY and 251 genes related to COVID-19 were selected, among which there were 45 target genes of DYY associated with treatment of COVID-19. This study demonstrated that the use of DYY in the treatment of COVID-19 involved a variety of biological processes, and DYY acted on key targets such as IL6, ILIB, and CCL2 through signaling pathways such as the IL-17 signaling pathway, AGE-RAGE signaling pathway in diabetic complications, and cytokine-cytokine receptor interaction. DYY might play a vital role in treating COVID-19 by suppressing the inflammatory storm and regulating immune function. Second, the molecular docking results showed that there was a certain affinity between the core compounds (kaempferol, quercetin, 7-Methoxy-2-methyl isoflavone, naringenin, formononetin) and core target genes (IL6, IL1B, CCL2). Finally, clinical studies showed that the level of IL6 was elevated in COVID-19 patients, and DYY can reduce its levels. CONCLUSIONS: DYY may treat COVID-19 through multiple targets, multiple channels, and multiple pathways and is worthy of clinical application and promotion.

Oxidative Stress Induction Is a Rational Strategy to Enhance the Productivity of Antrodia cinnamomea Fermentations for the Antioxidant Secondary Metabolite Antrodin C.

Antioxidant metabolites contribute to alleviating oxidative stress caused by reactive oxygen species (ROS) in microorganisms. We utilized oxidative stressors such as hydrogen peroxide supplementation to increase the yield of the bioactive secondary metabolite antioxidant antrodin C in submerged fermentations of the medicinal mushroom Antrodia cinnamomea. Changes in the superoxide dismutase and catalase activities of the cells indicate that ROS are critical to promote antrodin C biosynthesis, while the ROS production inhibitor diphenyleneiodonium cancels the productivity-enhancing effects of H2O2. Transcriptomic analysis suggests that key enzymes in the mitochondrial electron transport chain are repressed during oxidative stress, leading to ROS accumulation and triggering the biosynthesis of antioxidants such as antrodin C. Accordingly, rotenone, an inhibitor of the electron transport chain complex I, mimics the antrodin C productivity-enhancing effects of H2O2. Delineating the steps connecting oxidative stress with increased antrodin C biosynthesis will facilitate the fine-tuning of strategies for rational fermentation process improvement.

Bibliometric analysis of trends and issues in traditional medicine for stroke research: 2004-2018.

BACKGROUND: Stroke is a major cause of death and disability worldwide. Over the years, traditional medicines for stroke treatment have undergone tremendous progress, but few bibliometric studies have been performed. This study explored the trends and issues relating to the application of traditional medicine in stroke research. METHODS: A bibliometric search was performed in the Web of Science Core Collection database to identify studies that investigated the application of traditional medicine in stroke management. CiteSpace VI and Excel 2016 were used to analyze information from the retrieved studies. Activity index and attractive index were used to explore the worldwide development modes. RESULTS: A total of 1083 English articles published between 2004 and 2018 were identified. Over the last 15 years, the developments in research occurred in three geographic clusters. The development modes were investigated and classified into 4 categories. In mainland China, the number and impact of research showed an increasing trend over the study period. The United States played a leading role in this topic. Three clusters of institutes and the majority of authors mainly came from South Korea, Taiwan and mainland China. Reperfusion injury and angiogenesis were identified as the potential topics likely to dominate future research in this field. CONCLUSION: The progress of studies on traditional medicine for stroke could be explained by the global attention to traditional medicine, the geospatial proximity for research collabration, and the increasing resources invested. Based on a large amount of existing research, researchers engaged in this topic should objectively consider the influential studies to identify and solve the common issues worldwide.

Interdependent nitric oxide and hydrogen peroxide independently regulate the coix seed oil-induced triterpene acid accumulation in Ganoderma lingzhi.

Recent progress has been made in adding exogenous vegetable oils in culture media to promote bioactive metabolite production in several medicinal mushrooms, but the mechanism is still unclear. In this study, we found that the vegetable oil coix seed oil (CSO) could induce the biosynthesis of triterpene acids (TAs) and also significantly increase cytoplasmic nitric oxide (NO) and hydrogen peroxide (H2O2) concentrations in the mycelium of Ganoderma lingzhi. The change in TA biosynthesis caused by CSO could be reversed by adding NO scavenger or H2O2 scavenger, and adding NO scavenger or H2O2 scavenger resulted in the reduction of the cytoplasmic H2O2 or NO concentration under CSO treatment, respectively. Moreover, adding NO scavenger or H2O2 scavenger reversed TA biosynthesis, which could be rescued by H2O2 or NO donor, respectively. Taken together, our study indicated that both NO and H2O2 were involved in the regulation of TA biosynthesis, and CSO-activated NO and H2O2 were interdependent but independently regulated the TA biosynthesis under CSO treatment in G. lingzhi.

Analysis of environmental drivers influencing interspecific variations and associations among bloom-forming cyanobacteria in large, shallow eutrophic lakes.

Non-diazotrophic Microcystis and filamentous N2-fixing Aphanizomenon and Dolichospermum (formerly Anabaena) co-occur or successively dominate freshwaters globally. Previous studies indicate that dual nitrogen (N) and phosphorus (P) reduction is needed to control cyanobacterial blooms; however, N limitation may cause replacement of non-N2-fixing by N2-fixing taxa. To evaluate potentially counterproductive scenarios, the effects of temperature, nutrients, and zooplankton on the spatio-temporal variations of cyanobacteria were investigated in three large, shallow eutrophic lakes in China. The results illustrate that the community composition of cyanobacteria is primarily driven by physical factors and the zooplankton community, and their interactions. Niche differentiation between Microcystis and two N2-fixing taxa in Lake Taihu and Lake Chaohu was observed, whereas small temperature fluctuations in Lake Dianchi supported co-dominance. Through structural equation modelling, predictor variables were aggregated into 'composites' representing their combined effects on species-specific biomass. The model results showed that Microcystis biomass was affected by water temperature and P concentrations across the studied lakes. The biomass of two filamentous taxa, by contrast, exhibited lake-specific responses. Understanding of driving forces of the succession and competition among bloom-forming cyanobacteria will help to guide lake restoration in the context of climate warming and N:P stoichiometry imbalances.

Recycling of cooking oil fume condensate for the production of rhamnolipids by Pseudomonas aeruginosa WB505.

Rhamnolipids (RLs) are anionic biosurfactants with great application potential. This study explored the possibility of producing RLs from cooking oil fume condensates (COFCs) collected from range hoods. A mutant of Pseudomonas aeruginosa AB93066 was obtained and used to produce RLs from COFCs as a substrate. RL yields in a 7-L fermenter reached 12.3 g/L, and MALDI-TOF MS showed that Rha2-C10-C10 and Rha-C10-C10 are the most abundant (39.6% and 26.4%, respectively) RL components. The critical micellar concentration (CMC) of the RLs was 45.0 mg/L and the surface tension of water decreased from 60.5 to 25.3 mN/m. Using six kinds of common hydrocarbons as indices, the emulsification coefficients of the RLs obtained were found to exceed 60%; in particular, the emulsification coefficient for benzene was 80.3%. COFCs provide an inexpensive alternative as a substrate for RL production, and the synthetic process is relatively harmless and economical.

Production of bioactive metabolites by submerged fermentation of the medicinal mushroom Antrodia cinnamomea: recent advances and future development.

Edible and medicinal mushrooms have usually been considered as a sustainable source of unique bioactive metabolites, which are valued as promising provisions for human health. Antrodia cinnamomea is a unique edible and medicinal fungus widespread in Taiwan, which has attracted much attention in recent years for its high value in both scientific research and commercial applications owing to its potent therapeutic effects, especially for its hepatic protection and anticancer activity. Due to the scarcity of the fruiting bodies, the cultivation of A. cinnamomea by submerged fermentation appears to be a promising substitute which possesses some unique advantages, such as short culture time period and its high feasibility for scale-up production. However, the amount of fungal bioactive metabolites derived from the cultured mycelia of A. cinnamomea grown by submerged fermentation is much less than those obtained from the wild fruiting bodies. Hence, there is an urgent need to bridge such a discrepancy on bioactive metabolites between the wild fruiting bodies and the cultured mycelia. The objective of this article is to review recent advances and the future development of the mycelial submerged fermentation of A. cinnamomea in terms of enhancement for the production of fungal bioactive components by the optimization of culture conditions and the regulation of fungal metabolism. This review provides valuable information for further biotechnological applications of A. cinnamomea as well as other mushrooms being the source of bioactive ingredients by submerged fermentation.

Protective effects of Kangxian ruangan capsule against nonalcoholic fatty liver disease fibrosis in rats induced by MCD diet.

Kangxian ruangan (KXRG) capsule is a classical formula containing various herbals that play a vital role of replenishing spleen and warming Yang. Traditional Chinese medicine believes that insufficiency of the spleen, damp-heat, and phlegm and stasis are the key factors to nonalcoholic fatty liver disease (NAFLD). The objective of this study was to investigate the effects of KXRG capsule on NAFLD fibrosis rats induced by MCD diet. The liver functions (ALT, AST and GGT) and levels of blood lipids (CHOL and TG) in each treatment group rats were significantly decreased, especially those in H-KXRG group. At the same time, the KXRG capsule alleviated the inflammatory response, histopathological changes and liver fibrosis of NAFLD fibrosis rats. In addition, the apoptosis of liver cells induced by diet was obvious via TUNEL staining. However, KXRG capsule reversed that negative change. Moreover, the levels of pro-apoptotic proteins (Caspase 3, 8, 9 and Bax) were reduced by exposure to KXRG capsule, except that the anti-apoptotic proteins (Bcl-2 and Bcl-XL) were elevated. In conclusion, KXRG relieved the progression of NAFLD fibrosis via maintaining the balance of TNF-α/IL-10 further relieving the inflammatory reaction, and regulating the balance of Bcl-2/Bax or Bcl-XL/Bax in a positive direction further activating damaged hepatocytes.

Assessing the effects of rural livelihood transition on non-point source pollution: a coupled ABM-IECM model.

Water pollution caused by anthropogenic activities and driven by changes in rural livelihood strategies in an agricultural system has received increasing attention in recent decades. To simulate the effects of rural household livelihood transition on non-point source (NPS) pollution, a model combining an agent-based model (ABM) and an improved export coefficient model (IECM) was developed. The ABM was adopted to simulate the dynamic process of household livelihood transition, and the IECM was employed to estimate the effects of household livelihood transition on NPS pollution. The coupled model was tested in a small catchment in the Dongting Lake region, China. The simulated results reveal that the transition of household livelihood strategies occurred with the changes in the prices of rice, pig, and labor. Thus, the cropping system, land-use intensity, resident population, and number of pigs changed in the small catchment from 2000 to 2014. As a result of these changes, the total nitrogen load discharged into the river initially increased from 6841.0 kg in 2000 to 8446.3 kg in 2004 and then decreased to 6063.9 kg in 2014. Results also suggest that rural living, livestock, paddy field, and precipitation alternately became the main causes of NPS pollution in the small catchment, and the midstream region of the small catchment was the primary area for NPS pollution from 2000 to 2014. Despite some limitations, the coupled model provides an innovative way to simulate the effects of rural household livelihood transition on NPS pollution with the change of socioeconomic factors, and thereby identify the key factors influencing water pollution to provide valuable suggestions on how agricultural environmental risks can be reduced through the regulation of the behaviors of farming households in the future.

Fibroblast growth factor 21 deficiency exacerbates chronic alcohol-induced hepatic steatosis and injury.

Fibroblast growth factor 21 (FGF21) is a hepatokine that regulates glucose and lipid metabolism in the liver. We sought to determine the role of FGF21 in hepatic steatosis in mice exposed to chronic alcohol treatment and to discern underlying mechanisms. Male FGF21 knockout (FGF21 KO) and control (WT) mice were divided into groups that were fed either the Lieber DeCarli diet containing 5% alcohol or an isocaloric (control) diet for 4 weeks. One group of WT mice exposed to alcohol received recombinant human FGF21 (rhFGF21) in the last 5 days. Liver steatosis and inflammation were assessed. Primary mouse hepatocytes and AML-12 cells were incubated with metformin or rhFGF21. Hepatic genes and the products involved in in situ lipogenesis and fatty acid ß-oxidation were analyzed. Alcohol exposure increased circulating levels and hepatic expression of FGF21. FGF21 depletion exacerbated alcohol-induced hepatic steatosis and liver injury, which was associated with increased activation of genes involved in lipogenesis mediated by SREBP1c and decreased expression of genes involved in fatty acid ß-oxidation mediated by PGC1α. rhFGF21 administration reduced alcohol-induced hepatic steatosis and inflammation in WT mice. These results reveal that alcohol-induced FGF21 expression is a hepatic adaptive response to lipid dysregulation. Targeting FGF21 signaling could be a novel treatment approach for alcoholic steatohepatitis.

Reconstruction and analysis of the genome-scale metabolic model of schizochytrium limacinum SR21 for docosahexaenoic acid production.

BACKGROUND: Schizochytrium limacinum SR21 is a potential industrial strain for docosahexaenoic acid (DHA) production that contains more than 30-40 % DHA among its total fatty acids. METHODS: To resolve the DHA biosynthesis mechanism and improve DHA production at a systematic level, a genomescale metabolic model (GSMM), named iCY1170_DHA, which contains 1769 reactions, 1659 metabolites, and 1170 genes, was reconstructed. RESULTS: Based on genome annotation results and literature reports, a new DHA synthesis pathway based on a polyketide synthase (PKS) system was detected in S. limacinum. Similarly to conventional fatty acid synthesis, the biosynthesis of DHA via PKS requires abundant acetyl-CoA and NADPH. The in silico addition of malate and citrate led to increases of 24.5 % and 37.1 % in DHA production, respectively. Moreover, based on the results predicted by the model, six amino acids were shown to improve DHA production by experiment. Finally, 30 genes were identified as potential targets for DHA over-production using a Minimization of Metabolic Adjustment algorithm. CONCLUSIONS: The reconstructed GSMM, iCY1170_DHA, could be used to elucidate the mechanism by which DHA is synthesized in S. limacinum and predict the requirements of abundant acetyl-CoA and NADPH for DHA production as well as the enhanced yields achieved via supplementation with six amino acids, malate, and citrate.

Phytotoxic Mechanism of Nanoparticles: Destruction of Chloroplasts and Vascular Bundles and Alteration of Nutrient Absorption.

This study focused on determining the phytotoxic mechanism of CeO2 nanoparticles (NPs): destroying chloroplasts and vascular bundles and altering absorption of nutrients on conventional and Bt-transgenic cottons. Experiments were designed with three concentrations of CeO2 NPs including: 0, 100 and 500 mg·L(-1), and each treatment was three replications. Results indicate that absorbed CeO2 nanoparticles significantly reduced the Zn, Mg, Fe, and P levels in xylem sap compared with the control group and decreased indole-3-acetic acid (IAA) and abscisic acid (ABA) concentrations in the roots of conventional cotton. Transmission electron microscopy (TEM) images revealed that CeO2 NPs were absorbed into the roots and subsequently transported to the stems and leaves of both conventional and Bt-transgenic cotton plants via xylem sap. In addition, the majority of aggregated CeO2 NPs were attached to the external surface of chloroplasts, which were swollen and ruptured, especially in Bt-transgenic cotton. The vascular bundles were destroyed by CeO2 nanoparticles, and more damage was observed in transgenic cotton than conventional cotton.