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Six new prenylated flavonoid glycosides, including four new furan-flavonoid glycosides wushepimedoside A-D (1-4) and two new prenyl flavonoid derivatives wushepimedoside E-F (5-6), and one know analog epimedkoreside B (7) were isolated from biotransformation products of the aerial parts of Epimedium wushanense. Their structures were elucidated according to comprehensive analysis of HR-MS and NMR spectroscopic data, and the absolute configurations were assigned using experimental and calculated electronic circular dichroism (ECD) data. The regulatory activity of compounds 1-7 on the production of testosterone in primary rat Leydig cells were investigated, and 4 and 5 exhibited testosterone production-promoting activities. Molecular docking analysis suggested that bioactive compounds 4 and 5 showed the stable binding with 3β-HSD and 4 also had good affinity with Cyp17A1, which suggested that these compounds may regulate testosterone production through stimulating the expression of the above two key proteins.

Individual variations in metabolic rate, locomotion capacity and hypoxia tolerance and their relationships were investigated in three cyprinid species [crucian carp (Carassius auratus), common carp (Cyprinus carpio) and qingbo (Spinibarbus sinensis), in 60 individuals of each species]. Either the active metabolic rate (AMR) and critical swimming speed (Ucrit) (30 individuals) or critical oxygen tension (Pcrit) and loss of equilibrium (LOE) (30 individuals) were measured in each species after measuring the resting metabolic rate (RMR). Both the AMR and Ucrit were found to be significantly and positively correlated with the RMR in all three cyprinid species, indicating that high-RMR individuals have high aerobic capacity and thus good swimming performance. Pcrit was positively correlated with the RMR in all three species, whereas the LOE was highly positively correlated, weakly positively correlated and not correlated with the RMR in qingbo, common carp and crucian carp, respectively, possibly due to specialized morphological and biochemical adaptations involved in hypoxia tolerance in crucian and common carp. Crucian carp showed relatively poor swimming performance, i.e., a low Ucrit (relatively high variation), strong hypoxia tolerance, and low LOE (relatively low variation); qingbo showed relatively good swimming performance (relatively low variation) and weak hypoxia tolerance (relatively high variation); and common carp showed moderate swimming performance and relatively strong hypoxia tolerance (moderate variation). These interspecific differences may be due to the different lifestyles of these cyprinid fishes based on their associated fast-slow-flow regime and are outcomes of long-term selection.

The emergence of new highly pathogenic and drug-resistant influenza strains urges the development of novel therapeutics for influenza A virus (IAV). Here, we report the discovery of an anti-IAV microbial metabolite called APL-16-5 that was originally isolated from the plant endophytic fungus Aspergillus sp. CPCC 400735. APL-16-5 binds to both the E3 ligase TRIM25 and IAV polymerase subunit PA, leading to TRIM25 ubiquitination of PA and subsequent degradation of PA in the proteasome. This mode of action conforms to that of a proteolysis targeting chimera which employs the cellular ubiquitin-proteasome machinery to chemically induce the degradation of target proteins. Importantly, APL-16-5 potently inhibits IAV and protects mice from lethal IAV infection. Therefore, we have identified a natural microbial metabolite with potent in vivo anti-IAV activity and the potential of becoming a new IAV therapeutic. The antiviral mechanism of APL-16-5 opens the possibility of improving its anti-IAV potency and specificity by adjusting its affinity for TRIM25 and viral PA protein through medicinal chemistry.

Protein disulfide isomerase (PDI) plays a key role in maintaining cellular homeostasis by mediating protein folding via catalyzing disulfide bond formation, breakage, and rearrangement in the endoplasmic reticulum. Increasing evidence suggests that PDI can be a potential treatment target for several diseases. However, the function of PDI in the peripheral sensory nervous system is unclear. Here we report the expression and secretion of PDI from primary sensory neurons is upregulated in inflammatory and neuropathic pain models. Deletion of PDI in nociceptive DRG neurons results in a reduction in inflammatory and neuropathic heat hyperalgesia. We demonstrate that secreted PDI activates TRPV1 channels through oxidative modification of extracellular cysteines of the channel, indicating that PDI acts as an unconventional positive modulator of TRPV1. These findings suggest that PDI in primary sensory neurons plays an important role in development of heat hyperalgesia and can be a potential therapeutic target for chronic pain.

Akt is a promising therapeutic target for cancer treatment. In our study, we have identified that 7-deoxynarciclasine (7-DONCS) is a potential inhibitor of Akt, which results in the repression of multiple oncogenic processes in hepatocellular carcinoma (HCC). We have found that 7-DONCS suppresses the growth of HCC by inducing the apoptotic and autophagic capacities, as well as by inhibiting epithelial-mesenchymal transition (EMT) in vitro and in vivo. Pretreatment of cells with specific autophagy inhibitor (Bafilomycin A1) or knockdown of endogenous LC‐3B by siRNA strongly enhences 7‐DONCS‐regulated apoptosis and EMT. Consequently, we have found that 7-DONCS selectively inhibits phospho-Akt (Ser473), and subsequent molecular docking reveals that 7-DONCS directly binds to the C-terminal domain of Akt. Overexpressing Akt significantly blocks these effects via 7-DONCS in HCC cells. Furthermore, 7-DONCS, by targeting Akt, exhibits a promising therapeutic effect in orthotopic hepatocellular tumors. Finally, higher p-Akt expression is associated with poor prognosis, and higher level of Akt was positively correlated with the enrichment of both apoptosis and autophagy downregulation, and EMT upregulation in HCC patients. These studies suggest that 7-DONCS serves as an attractive drug candidate by targeting Akt for future HCC therapy.

Peiyuan Tongnao capsule (PTC) plays an important role in clinical application due to its excellent curative efficacy in the treatment of ischemic stroke and chronic cerebral circulation insufficiency. To standardize and rationalize the clinical application of PTC, a rapid and sensitive method based on ultra-high performance liquid chromatography/quadrupole-Orbitrap mass spectrometry with parallel reaction monitoring (PRM) mode was developed and validated for the pharmacokinetic (PK) study. Ten bioactive compounds (aucubin, salidroside, echinacoside, paeoniflorin, verbascoside, liquiritin, 2,3,5,4'-tetrahydroxy stilbene-2-O-β-d-glucoside, coumarin, glycyrrhizic acid, and emodin) were simultaneously determined in rat plasma. All calibration curves exhibited good linearity (r2 > 0.99). The lower limits of quantification were 0.082-13.291 ng mL-1 . The intra- and inter-day precision was 0.54-12.36%, whereas the intra- and inter-day accuracy ranged from 100.45 to 114.00%. The mean extraction recoveries were 81.77-117.66%, and the average matrix effects (MEs) were 86.23-109.96%. The high extraction recoveries and acceptable MEs indicated that the pretreatment method was feasible. And the stability was acceptable under various storage conditions and processing procedures. The validated method was successfully applied to the multiple components-PK studies, which lay the foundation for further pharmacological and clinical research of PTC and may provide a reference for other traditional Chinese medicines.

Muscle contraction activated by calcium ion is the key to reveal that honeybee abdomen can achieve various physiological activities through flexible exercises and contributes to a powerful mechanical function of muscle fibers. To investigate the stimulating effect of calcium ion on muscle fibers of honeybee abdomen, atomic force microscopy was used to measure the morphology structure and mechanical properties of muscle fibers from honeybee abdomen in different calcium ion solutions. The periodic morphology structure of muscle fibers stimulated by different calcium ion concentration changed greatly, and the sarcomere length contracted from 6.53 μm to 4.29 μm as the calcium ion concentration increased from 0.11 mM to 10 mM. The mechanical measurement showed that the elastic modulus of Z-line reached the maximum, followed by M-line, overlap zone and I-band in sequence at the same calcium ion concentration, and was approximately 3.636, 2.450, 2.284, 2.748 times that of I-band from 0.11 mM to 10 mM calcium ion concentration. Combining the experimental analysis, the calcium ion threshold range was obtained based on the response surface method. This work adequately elucidates biological structure and biomechanics of muscle fibers from honeybee abdomen and could provide reference for other similar muscle system.

Increasing pesticide contamination in foods of animal origin has made the wide-scope multi-residue analysis of pesticides an international concern. In this study, a sensitive and reliable multi-residue pesticide analysis method for beef was developed with the use of 129 pesticides to demonstrate the full scope of the method. The pesticides were extracted and purified using a modified QuEChERS technique and analysed using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. An orthogonal array design was employed for optimisation of the method, significantly scientising and simplifying the process. Method validation revealed satisfactory sensitivity with limits of quantification values ranging from 0.003 to 11.37 µg∙kg−1. Matrix effects ranged from 83.85% to 120.66%. Recovery at three spiking levels (20, 50, and 100 µg∙kg−1) were 70.51–128.12% and the intra-day and inter-day precisions were less than 20%, indicating good accuracy and precision.

Akt, a crucial protein involved in a variety of signaling pathways in cancer, acts as an important regulator of survival in hepatocellular carcinoma (HCC), and provides curative option for the related drugs development. We have found an active phenanthroindolizidine alkaloid, (13aR,14R)-9,11,12,13,13a,14-hexahydro-3,6,7-trimethoxydibenzo[f,h]pyrrolo[1,2-b]isoquinolin-14-ol (HTBPI), is a promising Akt inhibitor effective in the suppression of HCC cells proliferation through stimulating apoptotic and autophagic capability in vivo and in vitro. Treatment of HTBPI combined with a classical autophagy-lysosomal inhibitor (bafilomycin A1), could enhance stimulation effects of apoptosis on HCC cell lines. In addition, we confirmed HTBPI targeting Akt, occupied the kinase binding domain (Thr 308) of Akt to inactivate its function by CETSA and DARTS assay. In contrast, ectopic Akt-induced overexpression significantly abrogated inhibitory effects of HTBPI on cell viability and proliferation. Furthermore, high p-Akt (Thr 308) expression is collated with liver tumor formation and poor survival in HCC patients. In conclusions, HTBPI impeded HCC progress through regulation of apoptosis and autophagy machinery via interaction with p-Akt (Thr 308). This may provide potential molecular candidate by targeting Akt for the therapy of HCC patients.

Lycorine is a multifunctional bioactive compound, and it possesses potential anticancer activities. However, little is known about the underlying mechanism. In this research, we have found that lycorine significantly induces the apoptotic and autophagic capacities of hepatocellular carcinoma (HCC) cells in vitro and in vivo. Treatment with specific autophagy inhibitor (3-methyladenine/Bafilomycin A1) or knockdown of LC-3B/Atg5 by siRNA drastically enhances the apoptotic cell death effect by facilitating the switch from autophagy to apoptosis. Molecular validation mechanistically demonstrates that lycorine-induced apoptosis and autophagy in HCC cells is associated with decreased protein levels of tongue cancer resistance–associated protein 1 (TCRP1), and we further find that inhibition of TCRP1 decreases phosphorylation level of Akt and represses Akt/mTOR signaling. Finally, lycorine-induced apoptosis and autophagy suppress the growth of xenograft hepatocellular tumors without remarkable toxicity. Our results elucidate a novel molecular mechanism whereby lycorine promotes apoptosis and autophagy through the TCRP1/Akt/mTOR pathway in HCC. Our results reveal that lycorine might be a potential therapeutic agent for the treatment of HCC. Mol Cancer Ther; 16(12); 2711–23. ©2017 AACR.

Previous studies have suggested that Lycium barbarum (L. barbarum) has a radioprotective function, although more in-depth investigation is still required. We investigated the radioprotective efficacy of extract of the fruits of L. barbarum (LBE) and its radioprotective mechanisms. Mice were exposed to 8.5 Gy, 5.5 Gy, or 6.0 Gy total body irradiation (TBI), and the survival rate, lymphocyte percentage, amount of cytokines, and viability of the irradiated cells, as well as the gut microbiome and fecal metabolomics were studied. LBE enhanced the survival of the mice exposed to 8.5 Gy γ-ray TBI or 5.5 Gy X-ray TBI. After 6.0 Gy γ-ray TBI, LBE exhibited good immunomodulatory properties, mainly characterized by the accelerated recovery of lymphocyte percentages, and the enhanced expression of immune-related cytokines. LBE reconstituted the gut microbiota of irradiated mice, increased the relative abundance of potentially beneficial genera (e.g., Turicibacter, Akkermansia), and decreased the relative abundance of potentially harmful bacterial genera (e.g., Rikenellaceae_RC9_gut_group). Beneficial regulatory effects of LBE on the host metabolites were also noted, and the major upregulated metabolites induced by LBE, such as Tetrahydrofolic acid and N-ornithyl- L -taurine, were positively correlated with the immune factor interleukin (IL)-6. In vitro, LBE also increased the vitality of rat small intestinal epithelial cells (IEC-6) after 4.0 Gy γ-ray irradiation and promoted the growth of Akkermansia muciniphila. These results confirmed a radioprotective function of LBE and indicated that the radioprotective mechanism may be due to immunomodulation and the synergistically modulating effect on the gut microbiota and related metabolites.

Ensuring food safety requires effective methods for the simultaneous analysis of pesticide residues in animal-origin foods. A sensitive and reliable method for the multi-residue analysis of 126 pesticides in chicken muscle was developed using a modified QuEChERS technique and ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. A new enhanced matrix removal-lipid material was used as the QuEChERS dispersive purification adsorbent. Method validation revealed satisfactory linearities with correlation coefficients higher than 0.994 for all pesticides. All limits of quantification were below 10 µg/kg, except in the cases of oxadiazon, clomazone, and lactofen. The matrix effects were nearly negligible, ranging from 73.09% to 125.22%. The recoveries at three spiked levels (50, 100, and 200 μg/kg) were 71.38–120.43% and the intra-day and inter-day precisions were lower than 10%, indicating the good accuracy and precision of the established method.

Acclimation temperature is crucial for the optimization of a condition in aquaculture; we experimentally investigated the effects of temperature acclimation on the thermal tolerance, growth performance and gene expression levels of heat shock proteins (hsp70), growth hormone (gh) and insulin-like growth factors (igf-1) in Schizothorax prenanti, a cold-water fish in the Yangtze River basin. Critical thermal maximum (CTmax), critical thermal minimum (CTmin), lethal thermal maximum (LTmax), lethal thermal minimum (LTmin), feeding intake (FI), feeding efficiency (FE), and specific growth rate (SGR) were assessed at three stable temperatures (17, 22 and 27 °C) and one variable temperature (22 ± 5 °C) for 28 d. Better growth performance was observed under variable treatment compared to stable treatments. However, fish under the 27 °C treatment exhibited much weaker growth performance than those in the 17 °C treatment. Fish under variation temperature treatment fed like those under 22 °C treatment; the fish exhibited similar SGR but a higher gh and hsp70 level under variation temperature treatment. This may be due in part to a trade-off energy expenditure to deal with the temperature fluctuation. Together, these findings suggest that juvenile Schizothorax prenanti are resilient to daily fluctuations within the temperature tested here.

Anemarrhena asphodeloides is an herb widely used to treat symptoms associated with diabetes in traditional Chinese medicine. However, its key components and metabolites have low bioavailability and poor host absorption. To clarify the anti-diabetic mechanism of A. asphodeloides extract (AAE), we examined the anti-diabetic effects of AAE in rats with diabetes induced by a high-fat diet and streptozotocin. Faeces levels of the main components and metabolites of AAE were significantly higher than levels in plasma, which indicated that gut microbiota might play important roles in its anti-diabetic effect. Microbiological studies showed that unabsorbed components increased the diversity of the gut microbiota, enriched potentially beneficial bacteria, and suppressed potentially harmful bacteria. In vitro studies showed that AAE promoted the proliferation of Blautia coccoides, a bacterium with positive implication for diabetes, in a dose-dependent manner. AAE also promoted pancreatic cell regeneration and restored the function of pancreatic islet cells via peroxiredoxin 4 overexpression. Overall, these results suggest that AAE alleviates diabetes via modulating gut microbiota and protein expression.

We investigated the effects of starvation and re-feeding on growth and swimming performance and their relationship in juvenile black carp (Mylopharyngodon piceus). We measured the specific growth rate (SGR), resting metabolic rate (RMR) and constant acceleration test speed (U CAT, the maximum swimming speed at exhaustion by constant acceleration test with 0.1667 cm s(-2) rate) in a treatment group (21 days of starvation then 21 days of re-feeding) and control group (routine feeding) (n = 20). Starvation resulted in a 17 % decrease in body mass of black carp (P

Magnolin is a multi-bioactive natural compound that possesses underlying anti-cancer properties. However, the mechanisms underlying remain to be elucidated. Here, we report the role of magnolin in suppressing human colorectal cancer (CRC) cells via activating autophagy and cell cycle arrest in vitro and in vivo. Pre-treatment of cells with specific autophagy inhibitor (3-methyladenine) or knockdown of endogenous LC-3B by siRNA significantly abrogates magnolin-induced cell cycle arrest. Molecular validation mechanistically shows that magnolin-induced autophagy and cell cycle arrest in CRC cells is correlated with decreased transcriptional levels of leukemia inhibitory factor (LIF), and we further find that inhibition of LIF decreases phosphorylation level of Stat3 and represses transcriptional expression of Mcl-1. Furthermore, magnolin-induced autophagy and cell cycle arrest suppress the growth of xenograft colorectal tumors without apparent toxicity. Finally, we evaluate the clinical correlation of LIF/Stat3/Mcl-1 in CRC patient tissues. As expected, LIF, p-Stat3, and Mcl-1 levels are high in CRC tissue but are scarcely found in normal colon tissue. High positive expressions of LIF or Mcl-1 are associated with poor prognosis. Doubly positive cases have shown the worst outcome. Taken together, our results have clarified a novel molecular mechanism whereby magnolin induces autophagy and cell cycle arrest through LIF/Stat3/Mcl-1 pathway in CRCs. Our results also have revealed that magnolin has a promising therapeutic potential in CRCs.

Five new steroidal saponins ( 1 – 5 ) were isolated from the fermentation broth of total furostanol glycosides from tubers of Dioscorea zingiberensis C.H. Wright incubated with a fungal, Absidia coerulea AS 3.3389, along with known saponins, zingiberensis new saponin ( 6 ), deltonin ( 7 ), prosapogenin A of dioscin ( 8 ), and protobioside ( 9 ), and their structures were established by NMR spectroscopy and mass spectrometry as well as by comparison with previously reported spectral data in the literatures. The induced effects in vitro on rat platelet aggregation of all compounds were evaluated.

Exposure to acute stress leads to diverse changes, which include either beneficial or deleterious effects on molecular levels that are implicated in stress-related disorders. N-methyl-d-aspartate receptor (NMDAR)-mediated signalings, are thought to be vital players in stress-related mental disorders as well as attractive therapeutic targets for clinical treatment. In the present study, we utilized acute stress models in mice to explore regulation of phosphorylation level of S1284 in GluN2B subunit of NMDAR. We found out that forced swimming and acute restraint stress increased phosphorylation level of S1284, while phosphorylation level of S1284 was unaltered after brief exposure to open field. Moreover, phosphorylation change of S1284 was negated by treatment of roscovitine which is believed to be a Cyclin-dependent kinase inhibitor. Besides, we showed well correlation of phosphorylation change of S1284 and immobility time during forced swimming. Collectively, our results demonstrated that phosphorylation level of S1284 in GluN2B was regulated by acute stress.

Individual variation in growth, metabolism and swimming performance, their possible interrelationships, and the effects of temperature were investigated in 30 juvenile common carp (Cyprinus carpio) at two acclimation temperatures (15 and 25°C). We measured body mass, critical swimming speed (Ucrit), resting metabolic rate (RMR), active metabolic rate (AMR) and metabolic scope (MS) twice (28days apart) in both temperature groups. Fish acclimated to 25°C showed a 204% higher specific growth rate (SGR) than those acclimated to 15°C due to a 97% higher feeding rate (FR) and a 46% higher feed efficiency (FE). Among individuals, SGR was positively correlated with the FR and FE at both low and high temperatures. All measured variables (Ucrit, RMR and AMR) related to swimming except MS showed a high repeatability after adjusting for body mass (mass-independent). Fish acclimated to 25°C had a 40% higher Ucrit compared with 15°C acclimated fish, which was at least partially due to an improved metabolic capacity. AMR showed a 97% increase, and MS showed a 104% parallel increase with the higher acclimation temperature. Residual (mass-independent) Ucrit was positively correlated with residual RMR, AMR and MS, except for the residual RMR at high temperature. When acclimated to the lower temperature, both the residual and absolute Ucrit were negatively correlated with FR and FE and, hence, with SGR, suggesting a functional trade-off between growth and locomotion in fish acclimated to low temperatures. However, when acclimated to the higher temperature, this trade-off no longer existed; absolute Ucrit was positively correlated with SGR because individuals with rapid growth exhibited greatly increased body mass. The higher metabolic capacity at 25°C showed a positive effect on both swimming performance and growth rate (because of improved digestive efficiency) under the high-temperature condition, which we did not anticipate. Overall, these results indicate that temperature alters the relationship between growth and swimming performance of juvenile common carp. This change may be an adaptive strategy to seasonal temperature variation during their life history.

To investigate the effects of temperature and exercise training on swimming performance in juvenile qingbo (Spinibarbus sinensis), we measured the following: (1) the resting oxygen consumption rate \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \left( {{\dot{\text{M}}\text{O}}_{{ 2 {\text{rest}}}} } \right) $$\end{document}, critical swimming speed (Ucrit) and active oxygen consumption rate \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \left( {{\dot{\text{M}}\text{O}}_{{ 2 {\text{active}}}} } \right) $$\end{document} of fish at acclimation temperatures of 10, 15, 20, 25 and 30 °C and (2) the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \dot{M}{\text{O}}_{{ 2 {\text{rest}}}} $$\end{document}, Ucrit and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \dot{M}{\text{O}}_{{ 2 {\text{active}}}} $$\end{document} of both exercise-trained (exhaustive chasing training for 14 days) and control fish at both low and high acclimation temperatures (15 and 25 °C). The relationship between Ucrit and temperature (T) approximately followed a bell-shaped curve as temperature increased: Ucrit = 8.21/{1 + [(T − 27.2)/17.0]2} (R2 = 0.915, P

To investigate the effects of hypoxia acclimation, exercise training and fasting on the swimming performance of juvenile qingbo (Spinibarbus sinensis), we measured the critical swimming speed (U crit), resting and excess post-exercise oxygen consumption (EPOC) of control, hypoxia-acclimated, exercise-acclimated and fasting fish at 25°C. The muscle and plasma metabolites before and after a bout of exhaustive exercise (produced by chasing) were also measured. The fish were acclimated to hypoxia (48 h at 1.0 mg L−1, 12.5% air saturation), exercise training (2 weeks at 60% of U crit, 6 h daily) or fasting (2 weeks). All treatments resulted in significantly lower resting oxygen consumption ( $$ {\dot{\text{M}}} $$ O2rest) but had no effect on the magnitude of EPOC. Hypoxia acclimation had no effect on U crit or peak post-exercise oxygen consumption ( $$ {\dot{\text{M}}} $$ O2peak) but produced a higher depletion of muscle [glycogen] post-chasing (P

Nine spirostanol saponins (1-9) and seven mixtures of 25 R and 25 S spirostanol saponin isomers (10-16) were obtained from the seeds of Trigonella foenum-graecum after enzymatic hydrolysis of the furostanol saponin fraction by β-glucosidase. Their structures were determined by NMR and MS spectroscopy. Among them, 1- 4, 6, 8, and 9 were new compounds and five, 11B, 12A, 13B, 14A, and 14B, were new structures observed from seven mixtures. In addition, the inhibitory effects of all saponins on rat platelet aggregation were evaluated.

To investigate the effect of fasting on maintenance metabolism, feeding metabolism and aerobic swimming performance as well as their metabolic interactions in juvenile southern catfish, we measured the following: (1) the postprandial oxygen consumption ( M ˙ O 2 ) response (16% body mass meal size) after 0 (control), 1, 2 and 4 weeks of fasting and (2) the swimming performance of non-digesting and digesting fish after either 0, 1, 2 or 4 weeks of fasting. The fasting groups displayed with lower resting M ˙ O 2 ( M ˙ O 2 rest), lower peak postprandial M ˙ O 2 ( M ˙ O 2 peak), larger energy expenditures and longer digestive processes than those of the control groups. The critical swimming speed (Ucrit), the active M ˙ O 2 ( M ˙ O 2 active) and the metabolic scope ( M ˙ O 2 active - M ˙ O 2 rest, MS) of both non-digesting and digesting fish all decreased progressively after 1, 2 and 4 weeks of fasting, with those of non-digesting fish decreased more acutely than digesting fish (P M ˙ O 2 active than that of non-digesting fish in the 0-, 1-, 2- and 4-week fasting groups. Digestion only caused a significantly lower Ucrit and MS in both the 0- and 1-week fasting groups (P M ˙ O 2 increased greatly with the swimming speed, and digestion caused a higher M ˙ O 2 when compared to that of the fasting fish in any groups. The M ˙ O 2 of fish in the 4-week fasting group was significantly lower than that of other groups when the swimming speed was the same. In conclusion, both digestive and locomotive functions were down-regulated during fasting. In the 0- and 1-week fasting groups, the decreased MS for swimming during digestion caused a lower Ucrit (i.e., a digestion priority model). However, because the M ˙ O 2 active of digesting fish decreased much more slowly than that of fasting fish, the MS of the 2- and 4-week fasting groups did not change during digestion, and the fish could handle both physiological activities independently (i.e., an additive model).

A rapid, sensitive and specific ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method was developed to investigate the pharmacokinetics and tissue distribution of Eclipta prostrata extract. Rats were orally administrated the 70% ethanol extract of E. prostrata, and their plasma as well as various organs were collected. The concentrations of seven main compounds, ecliptasaponin IV, ecliptasaponin A, apigenin, 3'-hydroxybiochanin A, luteolin, luteolin-7-O-glucoside and wedelolactone, were quantified by UPLC-MS/MS through multiple reactions monitoring method. The precisions (RSD) of the analytes were all

To test whether the effects of feeding on swimming performance vary with acclimation temperature in juvenile southern catfish (Silurus meridionalis), we investigated the specific dynamic action (SDA) and swimming performance of fasting and feeding fish at acclimation temperatures of 15, 21, 27, and 33 degrees C. Feeding had no effect on the critical swimming speeding (U(crit)) of fish acclimated at 15 degrees C (p=0.66), whereas it elicited a 12.04, 18.70, and 20.98% decrease in U(crit) for fish acclimated at 21, 27 and 33 degrees C, respectively (p

Effects of feeding on pre-exercise VO(2) and excess post-exercise oxygen consumption (EPOC) after exhaustive exercise were investigated in sedentary southern catfish, active herbivorous grass carp, omnivorous crucian carp, and sluggish omnivorous darkbarbel catfish to test whether feeding had different effects on EPOC and to compare EPOC in fishes with different ecological habits. For fasting fish, the pre-exercise and peak post-exercise VO(2) were higher and recovery rates were faster in crucian carp and grass carp compared to those of darkbarbel catfish and southern catfish. EPOC magnitudes of grass carp and southern catfish were significantly larger than those of crucian carp and darkbarbel catfish. Feeding had no significant effect on peak post-exercise VO(2), recovery rate, and EPOC magnitude in grass carp. Both the pre-exercise and peak post-exercise VO(2) increased with meal size, while the EPOC magnitude and duration decreased significantly in the larger meal size groups of crucian carp and southern catfish. In darkbarbel catfish, both the pre-exercise and peak post-exercise VO(2) increased with meal size, but the VO(2) increment elicited by exercise was larger in feeding groups compared with the fasting group. These results suggest that (1) the characteristics of the post-exercise VO(2) profile, such as peak post-exercise VO(2) and recovery rate, were closely related to the activity of fishes, whereas the EPOC magnitude was not and (2) the effects of feeding on EPOC were more closely related to the postprandial increase in VO(2).

To investigate the effects of starvation and acclimation temperature on the escape ability of juvenile rose bitterling (Rhodeus ocellatus), we measured the fast-start escape and constant acceleration swimming performance of fish fasted for 0 (control), 1 and 2 weeks and half-lethal periods (6 or 4 weeks) at two temperatures (15 and 25 °C). Fish acclimated at a high temperature exhibited shorter response latency (R), higher maximum linear velocity (V max) and longer escape distance during escape movement (D 120ms) than those at the low temperature. Starvation resulted in a significant decrease in V max and D 120ms at either low or high temperature and a significant increase in R at only the high temperature in the half-lethal period groups (P

Using the absorbent resin, silica gel and ODS column chromatography as well as semi-preparative HPLC, ten compounds were isolated from 70% ethanol extract of tubers of Dioscorea zingiberensis C. H. Wright, and their structures were elucidated as trigoneoside XIIIa (1), parvifloside (2), trigoneoside IVa (3), deltoside (4), protobioside (5), lilioglycoside k (6), zingiberensis newsaponin I (7), deltonin (8), prosapogenin A of dioscin (9), and trillin (10) on the basis of NMR and MS spectral data analysis. Among these compounds, 1, 3, 5 and 6 were isolated from this plant for the first time. In the screening test on platelet aggregation, compounds 7 and 8 exhibited induction effect on platelet aggregation, while compound 9 exhibited significant inhibitory effect on platelet aggregation in vitro.

To investigate the effect of temperature on the repeat constant acceleration swimming performance and on the metabolic recovery capacity in juvenile qingbo (Spinibarbus sinensis), their constant acceleration test speed (U CAT) and excess post-exercise oxygen consumption (EPOC) recovery process were measured twice with 1-h intervals at different acclimation temperatures (10, 15, 20, 25 and 30 °C). Temperature significantly affected U CAT, the pre-exercise metabolic rate (MO2), metabolic peak values (MO2peak), the metabolic scope (MS, MO2peak—pre-exercise MO2) and the magnitude of the EPOC (P

We measured the following variables to investigate the effects of fasting and temperature on swimming performance in juvenile qingbo (Spinibarbus sinensis): the critical swimming speed (Ucrit), resting metabolic rate (ṀO2rest) and active metabolic rate (ṀO2active) of fish fasting for 0 (control), 1, 2 and 4 weeks at low and high acclimation temperatures (15 and 25°C). Both fasting treatment and temperature acclimation had significant effects on all parameters measured (P0.05). Fasting at the higher temperature had a negative effect on all measured parameters after 1 week (P0.05). However, when acclimated to the lower temperature, fasting had a negative effect on Ucrit until week 2 and on (ṀO2rest), (ṀO2active) and metabolic scope (MS, (ṀO2active)-(ṀO2rest)) until week 4 (P0.05). The values of all parameters at the lower temperature were significantly lower than those at the higher temperature in the identical fasting period groups except for (ṀO2rest) of the fish that fasted for 2 weeks. The relationship between fasting time (T) and Ucrit was described as Ucrit(15)=-0.302T(2)-0.800T+35.877 (r=0.781, n=32, P0.001) and Ucrit(25)=0.471T(2)-3.781T+50.097 (r=0.766, n=32, P0.001) at 15 and 25°C, respectively. The swimming performance showed less decrease in the early stage of fasting but more decrease in the later stage at the low temperature compared to the high temperature, which might be related to thermal acclimation time, resting metabolism, respiratory capacity, energy stores, enzyme activity in muscle tissue and energy substrate utilization changes with fasting between low and high temperatures. The divergent response of the swimming performance to fasting in qingbo at different temperatures might be an adaptive strategy to seasonal temperature and food resource variation in their habitat.

Summary This study quantified and compared hypoxia tolerance and swim performance among cyprinid fish species from rapid-flow, slow-flow and intermediate-flow habitats (4 species per habitat) in China. In addition, we explored effects of short-term acclimation on swim performance, maximum metabolic rate (Mo2 max) and gill remodelling to detect habitat-associated patterns of plastic response to hypoxia. Indices of hypoxia tolerance included oxygen threshold for loss of equilibrium (LOE50) and aquatic surface respiration (ASR50) and critical oxygen tension for routine metabolic rate (Pcrit). Critical swimming speed (Ucrit) and Mo2 max were measured under normoxic and hypoxic conditions after 48 hours acclimation to normoxia and hypoxia, and gill remodelling was estimated after 48 hours of hypoxia exposure. Both traditional ANCOVA and phylogenetically independent contrast (PDANOVA) analyses showed that fish species from rapid-flow habitat exhibited lower LOE50 compared to fish from intermediate and slow-flow habitats. Habitat-specific difference in Pcrit and Ucrit were detected using PDANOVA but not traditional ANCOVA analyses, with fish species from rapid-flow habitat exhibited lower Pcrit but higher Ucrit compared to fish from intermediate and slow-flow habitats. Fish species from rapid-flow habitats were also characterized by less plasticity in swim performance and gill morphology in response to hypoxia acclimation compared to species from slow-flow habitats, but a greater drop in swim performance in response to acute hypoxia exposure. The study detected a habitat-specific difference in hypoxia tolerance, swimming performance and its plasticity among fish from habitats with different flow conditions possibly due to the long-term adaptation to the habitat caused by selection stress. The phylogenetically independent contrasts were more powerful than traditional statistical analyses according to the habitat effects in both hypoxia tolerance and swimming performance in this study.

The Wujiang River, a tributary of the Three Gorges Reservoir, has many dams along its length. These dams alter the river's natural habitat and produce various flow regimes and degrees of predator stress. To test whether the swimming performance and external body shape of pale chub (Zacco platypus) have changed as a result of alterations in the flow regime and predator conditions, we measured the steady (U crit) and unsteady (fast-start) swimming performances and morphological characteristics of fish collected from different sites along the Wujiang River. We also calculated the maximum respiratory capacity and cost of transport (COT). We demonstrated significant differences in swimming performance and morphological traits among the sampling sites. Steady swimming performance was positively correlated with water velocity and negatively correlated with the abundance of predators, whereas unsteady swimming performance was negatively correlated with water velocity. The body shape was significantly correlated with both swimming performance and ecological parameters. These findings suggested that selection pressure on swimming performance results in a higher U crit and a more streamlined body shape in fast-flow and (or) in habitats with low predator stress and subsequently results in a lower COT. These characteristics were accompanied by a poorer fast-start performance than that of the fish from the slow-flow and (or) high-predator habitats. The divergence in U crit may also be due in part to variation in respiratory capacity.

To test whether the effects of temperature on the metabolic mode changed among different fish species, we investigated the specific dynamic action (SDA) and swimming performance of fasting and fed fish at 15 and 25°C in three juvenile Cyprinidae fish species: goldfish (Carassius auratus), common carp (Cyprinus carpio) and qingbo (Spinibarbus sinensis). Both taxon and temperature had significant effects on the resting oxygen consumption rate (M˙O(rest)), SDA and swimming performance (p

SUMMARY To test the hypothesis that digestion has a more notable physiological effect on ambush foragers than on active foragers, we investigated the behavioural, digestive and metabolic characteristics, as well as the postprandial locomotory capacity, of four species of juvenile fish distributed along the Yangtze River, China, with distinct foraging strategies. The ambush foraging southern catfish (Silurus meridionlis) had the fewest movements per minute (MPM), lowest per cent time spent moving (PTM), slowest critical swimming speed (Ucrit), lowest maintenance metabolism(V̇O2rest) and lowest maximum locomotory metabolism(V̇O2max). However, the southern catfish had the highest feeding level and maximum feeding metabolism(V̇O2peak) and the greatest decrease in Ucrit after consumption of a large meal. Thus, this fish is highly adapted to its ambush behavioural strategy and sedentary life style. In the herbivorous grass carp (Ctenopharyngodon idellus), a low digestive capacity led to little change in postprandial locomotory performance, which benefits its frequent grazing behaviour. In this species, the greater amount of energy spent on routine activity and avoiding predators versus Ucrit might be related to its herbivorous life style and high predation risk. The active foraging crucian carp(Carassius auratus) adopts a unique high energy cost strategy that allows for high capacity in both routine activity and digestion, and the great flexibility of its cardio-respiratory capacity (increased V̇O2max after feeding) guarantees a small decrease in Ucrit even after maximum feeding. Finally, the sluggish foraging darkbarbel catfish(Pelteobagrus vachelli) has low digestive and locomotory capacity,but its energy-efficient venomous defence strategy may be related to its abundance. These results show that the digestive, behavioural and metabolic strategies differ among these fish species. The locomotory capacity in the sedentary fishes decreased profoundly after feeding, whereas it decreased little or not at all in the active fishes. The maintenance of high locomotory capacity after eating in the active fishes is probably related to a large metabolic capacity, a lower digestive capacity or an improvement in cardio-respiratory capacity after feeding.