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To explore the dynamic impacts of simulated microgravity (SM) on different vital brain regions of rats. Microgravity was simulated for 7 and 21 days, respectively, using the tail-suspension rat model. Histomorphology, oxidative stress, inflammatory cytokines and the expression of some key proteins were determined in hippocampus, cerebral cortex and striatum. 21-day SM decreased brain derived neurotrophic factor and induced neuron atrophy in the cerebral cortex. Strong oxidative stress was triggered at day 7 and the oxidative status returned to physiological level at day 21. Inflammatory cytokines were gradually suppressed and in striatum, the suppression was regulated partially through c-Jun/c-Fos. The results revealed that the significant impacts of SM on rat brain tissue depended on durations and regions, which might help to understand the health risk and to prevent brain damage for astronauts in space travel. [ABSTRACT FROM AUTHOR]

A 150 μm thick fully dense Ni coating was deposited on AZ31B magnesium alloy by a newly developed in-situ shot-peening-assisted cold spray process. Strong adhesion strength of Ni coating (>65.4 MPa) was achieved. The present Ni coated AZ31B reveals comparable electrochemical behavior with annealed bulk Ni in 3.5 wt.% NaCl aqueous solution. Long-term immersion test (1000 h) and NaCl salt spray test (1000 h) further verified the robust corrosion resistance of the cold sprayed Ni coating. This work provides a novel green approach for corrosion protection of magnesium alloys. [ABSTRACT FROM AUTHOR]

A novel approach has been developed to cold spray fully dense Cu deposits by using a mixed feedstock. The feedstock is composed of two raw powders with remarkably dissimilar microstructure and hardness: a hard and dense gas-atomized Cu powder (GA Cu) and a soft and porous electrolytic Cu powder (E Cu). It was found that when high velocity impact occurs between dissimilar Cu particles, the plastic deformation shows an asymmetrical feature and the strain is mainly concentrated on the soft side. This asymmetrical deformation behavior ensures that all the inter-particle space can be filled by the deformed soft particles and leads to a fully dense microstructure. An increment of ∼44% in deposition efficiency was achieved for the mixed feedstock as compared with the GA Cu powder. A high in-plane electrical conductivity of 79 %IACS (73 and 56 %IACS for GA coating and E coating, respectively) and high through thickness thermal conductivity of 285.6 W m −1 K −1 (207.1 and 133.8 W m −1 K −1 for GA coating and E coating, respectively) were achieved. The coating prepared by mixed powders shows an excellent corrosion resistance, comparable with that of the bulk Cu. This work gives a new strategy to improve the inter-particle bonding and get fully dense metallic deposits by feedstock design rather than spraying condition optimization. [ABSTRACT FROM AUTHOR]

Vascular aging, a major risk factor for cardiovascular disease, contributes to morbidity and mortality in older people. Mitochondria play an important role in vascular aging. In endothelial and smooth muscle cells, multiple changes in the mitochondrial structure and function contribute to aging, including the effects of mitochondrial oxidative stress, mitochondrial DNA mutations, mitochondrial dynamics, and mitophagy. Mitochondrial dysfunction also contributes to other age-related molecular and cellular mechanisms, such as crosstalk with telomeres, senescence-associated secretory phenotypes, and low-grade inflammation. Thus, enhancing mitochondrial biogenesis, reducing oxidative stress, recovering dynamics, and mitophagy have been suggested as effective interventions to delay vascular aging and age-related cardiovascular diseases. Furthermore, accumulating evidence has shown that commonly used herbs and their natural compounds have great potential to improve mitochondrial function during vascular aging. Herein, we review the cellular and molecular mechanisms of mitochondrial effects on vascular aging, emphasizing the efficacy of natural compounds in the treatment of vascular aging by improving mitochondrial structure and function. We aim to provide new insights into delaying vascular aging and preventing cardiovascular diseases. [Display omitted] • Mitochondrial dysfunction contributes to vascular aging, adversely affecting the health and longevity of the elderly. • Oxidative stress and dysfunction of mitochondrial DNA, dynamics and mitophagy can be found in senescent ECs and VSMCs. • Similar structure and crosstalk between mitochondria and telomeres together facilitate vascular aging. • Natural compounds from herbal medicine have great potential to improve mitochondrial function and delay vascular aging. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Salvia miltiorrhiza (SM, also known as DanShen) is one of the well-known widely used Chinese herbal medicines in clinical, containing phenolic compounds and potent antioxidant properties. Salvianolic acid A (SAA) is the most potent component of SM. A modern experimental strategy for treating myocardial ischemia is to induce neovascularization of the heart by the use of "angiogens", mediators that induce the formation of blood vessels, or angiogenesis. Studies demonstrated that coronary collateral vessels protect ischemic myocardium after coronary obstruction; therefore, we sought to examine whether SAA could stimulate myocardial angiogenesis. Materials and methods: Male Sprague–Dawley rats myocardial infarct (MI) induced by ligation of left anterior descending coronary artery (LAD) were randomly divided into five groups: sham-operated group; LAD occlusion + administration of physiological saline (vehicle treated group); LAD occlusion + administration of different concentrations of SAA (10, 5.0 and 2.5mg/kg/d). Infarct size and capillary density in the infarct region were measured with a previous experimental method. Immunohistological analysis was performed to measure vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-2 (VEGFR-2) expressions. The secretion of matrix metalloproteinase type X (MMP-9) was evaluated in serum of post-ischemic rats. We also performed the experiments of SAA on rat endothelial progenitor cells (EPCs) numbers and the capacity of migration and vasculargenesis. Results: SAA potentiated the ischemia-induced neovascularization after 1week post-operation when compared to vehicle treated group. This effect could be attributed to an increased formation of VEGF, VEGFR-2, and MMP-9 as well as the promotion of numbers and functions of EPCs. Conclusion: These findings show that SAA has potent proangiogenic properties by promoting the expression of proangiogenic factors, and the functions of EPCs, indicating that SAA might contribute to the protective effect against coronary disease. Chemical compound studied in this paper is salvianolic acid A (PubChem CID: 5281793) [ABSTRACT FROM AUTHOR]

Abstract: Dragon's blood is a bright red resin obtained from Dracaena cochinchinensis (Lour.) S.C.Chen (Yunnan, China). As a traditional Chinese medicinal herb, it has great traditional medicinal value and is used for wound healing and to stop bleeding. Its main biological activity comes from phenolic compounds. In this study, phenolic compounds were made into dropping pills and their protective effects were examined by establishing focal cerebral ischemia rats model used method of Middle Cerebral Artery Occlusion (MCAO), and by investigating indexes of neurological scores, infarct volume, cerebral index, cerebral water content and oxidation stress. Compared to model group, high, middle and low groups of Dragon's blood dropping pills could improve the neurological function significantly (p <0.01) and reduce cerebral infarct volume of focal cerebral ischemia rats remarkably (p <0.05–0.01). Meanwhile, each group could alleviate cerebral water content and cerebral index (p <0.05–0.01) and regulate oxidative stress of focal cerebral ischemia rats obviously (p <0.05–0.01). Activities of middle group corresponded with that treated with positive control drug. The results obtained here showed that Dragon's blood dropping pills had protective effects on focal cerebral ischemia rats. [Copyright &y& Elsevier]

Abstract: The origin of the superior high temperature strength of Ti-rich γ-TiAl with addition of Nb is a highly controversial issue. In this paper, we calculated the interaction energies between point defects in these alloys using a first-principles plane-wave pseudopotential method. It is found that, the nearest neighbouring Nb atoms on Al-sublattice (NbAl) repel whereas the next nearest neighbouring NbAl atoms attract each other, indicating that NbAl atoms may form short-range ordered structure. Based on this finding, we propose that the short-range order may be responsible for the high strength of the Ti-rich TiAl-Nb alloys. [Copyright &y& Elsevier]

Abstract: Ethnopharmacological relevance: Dragon''s Blood from Dracaena cochinchinensis (Lour.) S.C. Chen (Yunnan, China), as a traditional Chinese medicinal herb, was shown to have certain antithrombotic effects. A new preparation process was used to extract effective components from Dragon''s Blood. A 95% ethanol extract A (EA) and a precipitate B (PB) fraction were obtained and compared. Reliability of the preparation process was validated by pharmacodynamic experiments. Materials and methods: A rat/mouse thrombosis and blood stasis model was developed for this study, and EA and PB effects on thrombosis, platelet functions and blood coagulation activities were analyzed. Results: It was observed that the EA fraction had significantly better inhibitory effects than the PB fraction on thrombosis (p <0.05), platelet aggregation function (p <0.01) and anticoagulation activity (p <0.05–0.01). Conclusions: The results obtained here showed that EA fraction from Dragon''s Blood contained pharmacologically effective compounds with antithrombotic effects, partially improving platelet function and anticoagulation activity. [Copyright &y& Elsevier]

Salvia miltiorrhiza (SM, also known as DanShen) is one of the well-known widely-used Chinese herbal medicines in clinical practice. In this study we aimed to demonstrate the pro-angiogenic effects of Salvianolic acids (SAs) to treat illnesses such as ischemic cardiovascular diseases, the main active components of aqueous extract of SM. Materials and methods: To do this, new-born rat spleen mononuclear cells were isolated and endothelial progenitor cells (EPCs) were expanded (not more than 24h) SD. Then the pro-angiogenic activities of SAs were evaluated on in vitro cultured EPCs and chick embryo chorioallantoic membrane (CAM) model. And the adherent cells were stained with DiI complexed acetylated low-density lipoprotein (DiI-acLDL) and fluorescein Ulex Europaeus agglutinin-1 (FITC-UEA-1), and then viewed by laser scanning confocal microscope (LSCM) to confirm EPCs lineage. EPCs identification was also tested by ultrastructural analyses. EPCs proliferation, migration and in vitro vasculogenesis activity were assayed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, transwell chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating those on fibronectin-coated dishes, and then counting adherent cells. Results: EPCs phenotype was confirmed by the presence of double positive cells for DiI-acLDL uptake and lectin binding and identification of Weibel–Palade body in cytoplasm by ultrastructural analyses. Incubation of EPCs with SAs increased the number of EPCs and promoted EPCs migratory, adhesive and in vitro vasculogenesis capacity. SAs also promoted angiogenesis as evidenced by CAM model. Conclusions: The results of the present study suggest that SAs may have utility for therapeutic postnatal vasculogenesis of ischemic tissue, contributing to the clinical benefit of SM therapy in patients with coronary artery disease. [Copyright &y& Elsevier]

Highlights: [•] Rat NQO1 expressed in E. coli can transform SANG to DHSA in vitro. [•] NQO1 involves in the imine bond reductive of SANG. [•] NQO1 over expression can reduce cytotoxicity of SANG-induced BRL cells. [•] CYP1A over expression can increase cytotoxicity of SANG-induced BRL cells. [•] Over expression of NQO1 other than CYP1A1 was helpful to the protect BRL cells. [Copyright &y& Elsevier]

Abstract: The aim of present study was to evaluate the vasorelaxant effects of the flavonone pinocembrin and its possible mechanisms in isolated rat aortic rings. Pinocembrin (5 ∼100 μM) induced relaxation in aortic rings pre-contracted with norepinephrine (NE, 1 μM) or KCl (60 mM), with pEC50 value 4.37±0.02 and 4.52±0.04. Pretreatment with pinocembrin (30 or 50 μM) also inhibited contractile responses to NE and KCl. The vasorelaxant effect of pinocembrin relied on intact endothelium partially, and incubation with n ω-nitro-l-arginine methyl ester (l-NAME, 100 μM) or methylene blue (10 μM) significantly inhibited the effect, however indomethacin (5 μM) had no influence on the action. In endothelium-denuded rings, the vasorelaxant effect of pinocembrin was reduced by glibenclamide (10 μM), tetraethylammonium (5 mM) and 4-aminopyridine (100 μM). Pinocembrin also reduced NE-induced transient contraction in Ca2+-free solution and inhibited contraction induced by increasing external calcium in Ca2+-free medium plus 60 mM KCl. Our results suggest that pinocembrin induces relaxation in rat aortic rings through an endothelium-dependent pathway, involving NO-cGMP, and also through an endothelium-independent pathway, opening K+ channels and blockade of Ca2+ channels. [Copyright &y& Elsevier]

Gelsemium elegans Benth (G. elegans) is highly toxic to humans and rats, but has insecticides and growth promoting effects on pigs and goats. G. elegans is widely used in livestock, but its in vivo dynamics are entirely unknown. Hence, we investigated the toxicokinetic profiles of G. elegans alkaloids after a single oral dose of G. elegans to pigs (1.0 g/kg) and rats (0.1 g/kg). The results indicated that rats were more susceptible to the toxicity of G. elegans than pigs. The toxicokinetic parameters of 22 and 6 components were obtained in pigs and rats, respectively. The components included 9 and 5 gelsedine-type alkaloids in pigs and rats, respectively. The T max results of the 5 gelsedine-type alkaloids indicated that these alkaloids were rapidly absorbed in pigs and rats. The T 1/2 values of the 5 gelsedine-type alkaloids indicated that the elimination rates of these alkaloids in pigs were slower than those in rats. In addition, the C max and AUC results indicated that the degrees of absorption and exposure of most alkaloids in pigs were higher than those in rats except GS-2. However, the C max value of GS-2 (11-methoxy-14-hydroxygelsenicine) in rats was greater than that of pigs, and the C max value of 14-hydroxygelsenicine in pigs was merely greater than 3 times that of rats. The present results suggested that the cause of the toxicological differences species of G. elegans might be related to the degrees of absorption and exposure of gelsedine-type alkaloids, especially for the 14-hydroxygelsenicine and GS-2 in different animals. Image 1 • Toxicokinetic profiles of G. elegans alkaloids in pigs and rats were investigated firstly. • The C max and AUC results of most alkaloids in pigs were higher than those in rats except GS-2. • Toxicity of G.elegans is closely related to gelsedine-type alkaloids. • The differences of the toxicological species might be related to their degrees of absorption and exposure. [ABSTRACT FROM AUTHOR]