High estrogen during ovarian stimulation induced loss of maternal imprinted methylation that is essential for placental development via overexpression of TET2 in mouse oocytes.

BACKGROUND: Ovarian stimulation (OS) during assisted reproductive technology (ART) appears to be an independent factor influencing the risk of low birth weight (LBW). Previous studies identified the association between LBW and placenta deterioration, potentially resulting from disturbed genomic DNA methylation in oocytes caused by OS. However, the mechanisms by which OS leads to aberrant DNA methylation patterns in oocytes remains unclear. METHODS: Mouse oocytes and mouse parthenogenetic embryonic stem cells (pESCs) were used to investigate the roles of OS in oocyte DNA methylation. Global 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) levels were evaluated using immunofluorescence or colorimetry. Genome-wide DNA methylation was quantified using an Agilent SureSelectXT mouse Methyl-Seq. The DNA methylation status of mesoderm-specific transcript homologue (Mest) promoter region was analyzed using bisulfite sequencing polymerase chain reaction (BSP). The regulatory network between estrogen receptor alpha (ERα, ESR1) and DNA methylation status of Mest promoter region was further detected following the knockdown of ERα or ten-eleven translocation 2 (Tet2). RESULTS: OS resulted in a significant decrease in global 5mC levels and an increase in global 5hmC levels in oocytes. Further investigation revealed that supraphysiological ß-estradiol (E2) during OS induced a notable decrease in DNA 5mC and an increase in 5hmC in both oocytes and pESCs of mice, whereas inhibition of estrogen signaling abolished such induction. Moreover, Tet2 may be a direct transcriptional target gene of ERα, and through the ERα-TET2 axis, supraphysiological E2 resulted in the reduced global levels of DNA 5mC. Furthermore, we identified that MEST, a maternal imprinted gene essential for placental development, lost its imprinted methylation in parthenogenetic placentas originating from OS, and ERα and TET2 combined together to form a protein complex that may promote Mest demethylation. CONCLUSIONS: In this study, a possible mechanism of loss of DNA methylation in oocyte caused by OS was revealed, which may help increase safety and reduce epigenetic abnormalities in ART procedures.

Styrax (Liquidambar orientalis Mill.) promotes mitochondrial function and reduces cardiac damage following myocardial ischemic injury: the role of the AMPK-PGC1α signaling pathway.

OBJECTIVES: To explore the effect of extract of Styrax (ES) on myocardial ischemic injury and its molecular mechanism, indirectly providing a theoretical basis for the development of ES. METHODS: In order to assess the impact of ES treatment on ischemic heart disease, both a left anterior descending ligation-induced myocardial infarction (MI) model and an ischemia/hypoxia (I/H)-induced H9c2 cell injury model have been constructed. Specifically, Sprague-Dawley rats were randomly assigned to the following groups (n = 8) and administered intragastrically once a day for seven consecutive days: Sham group, MI group, ES-L (0.2 g/kg) group, ES-M (0.4 g/kg) group, ES-H (0.8 g/kg) group, and trimetazidine (TMZ, 0.02 g/kg) group. The cardiac functions and biochemical assessment of rats were detected. Then, we validated experimentally the targets and mechanism of ES on these pathological processes in I/H-induced H9c2 cell injury model. KEY FINDINGS: These results showed that different doses of ES (0.2 g/kg, 0.4 g/kg, 0.8 g/kg, intragastric) significantly improved myocardial structure and function when compared to the MI group. The results of 2,3,5-triphenyltetrazolium chloride (TTC), hematoxylin-eosin, and masson staining indicated that ES could significantly reduce infarct size, inhibit myocardium apoptosis, and decrease myocardial fibrosis. Moreover, ES distinctly suppressed the serum levels of lactate dehydrogenase (LDH), cardiac troponin T (cTnT), and creatine kinase-MB (CK-MB), alleviated myocardial mitochondrial morphology, and stimulated adenosine triphosphate (ATP) production, increased the level of succinate dehydrogenase (SDH), complex I and complex V activity. Different doses of ES (5 µg/ml, 10 µg/ml, 20 µg/ml) also improved cardiomyocyte morphology and decreased the apoptosis rate in H9c2 cells that had been exposed to I/H. Furthermore, the results of western blotting and qRT-PCR indicated that ES promoted the expression of proteins and mRNA related to energy metabolism, including phosphorylated adenosine monophosphate activated protein kinase (p-AMPK), peroxisome proliferator activated receptor gamma coactivator 1 alpha (PCG-1α), nuclear respiratory factor 1, and mitochondrial transcription factor A (TFAM). Mechanically, after the administration of Compound C (dorsomorphin), an AMPK inhibitor, these effects of myocardial protection produced by ES were reversed. CONCLUSIONS: Collectively, these results demonstrated that ES could improve myocardial mitochondrial function and reduce ischemic injury by activating AMPK/PCG-1α signaling pathway, while indicating its potential advantages as a dietary supplement.

Protective effect and mechanism of styrax on ischemic stroke rats: metabonomic insights by UPLC-Q/TOF-MS analysis.

CONTEXT: Styrax is used for prevention and treatment of cerebrovascular diseases. However, the underlying mechanism remains unclear. OBJECTIVE: To elucidate styrax's anti-ischemic stroke protective effects and underlying mechanisms. MATERIALS AND METHODS: An ischemic-stroke rat model was established based on middle cerebral artery occlusion (MCAO). Sprague-Dawley rats were randomly assigned to the following groups (n = 10) and administered intragastrically once a day for 7 consecutive days: sham, model, nimodipine (24 mg/kg), styrax-L (0.1 g/kg), styrax-M (0.2 g/kg) and styrax-H (0.4 g/kg). Neurological function, biochemical assessment, and ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS)-based serum metabonomics were used to elucidate styrax's cerebral protective effects and mechanisms. Pearson correlation and western blot analyses were performed to verify. RESULTS: The addition of 0.4 g/kg styrax significantly reduced cerebral infarct volume and neurobehavioral abnormality score. Different doses of styrax also decrease MDA, TNF-α, IL-6, and IL-1ß, and increase SOD and GSH-Px in ischemic-stroke rats (p < 0.05; MDA, p < 0.05 only at 0.4 g/kg dose). Biochemical indicators and metabolic-profile analyses (PCA, PLS-DA, and OPLS-DA) also supported styrax's protective effects. Endogenous metabolites (22) were identified in ischemic-stroke rats, and these perturbations were reversible via styrax intervention, which is predominantly involved in energy metabolism, glutathione and glutamine metabolism, and other metabolic processes. Additionally, styrax significantly upregulated phosphorylated AMP-activated protein kinase and glutaminase brain-tissue expression. CONCLUSION: Styrax treatment could ameliorate ischemic-stroke rats by intervening with energy metabolism and glutamine metabolism. This can help us understand the mechanism of styrax, inspiring more clinical application and promotion.

Advances of phytotherapy in ischemic stroke targeting PI3K/Akt signaling.

The pathogenesis of ischemic stroke is complex, and PI3K/Akt signaling is considered to play a crucial role in it. The PI3K/Akt pathway regulates inflammation, oxidative stress, apoptosis, autophagy, and vascular endothelial homeostasis after cerebral ischemia; therefore, drug research targeting the PI3K/Akt pathway has become the focus of scientists. In this review, we analyzed the research reports of antiischemic stroke drugs targeting the PI3K/Akt pathway in the past two decades. Because of the rich sources of natural products, increasing studies have explored the value of natural compounds, including Flavonoids, Quinones, Alkaloids, Phenylpropanoids, Phenols, Saponins, and Terpenoids, in alleviating neurological impairment and achieved satisfactory results. Herbal extracts and medicinal formulas have been applied in the treatment of ischemic stroke for thousands of years in East Asian countries. These precious clinical experiences provide a new avenue for research of antiischemic stroke drugs. Finally, we summarize and discuss the characteristics and shortcomings of the current research and put forward prospects for further in-depth exploration.

DNA-Templated Ag@Pd Nanoclusters for NIR-II Photoacoustic Imaging-Guided Photothermal-Augmented Nanocatalytic Therapy.

Developing multifunctional nanozymes with photothermal-augmented enzyme-like reaction dynamics in the second near-infrared (NIR-II) biowindow is of significance for nanocatalytic therapy (NCT). Herein, DNA-templated Ag@Pd alloy nanoclusters (DNA-Ag@Pd NCs) are prepared as a kind of novel noble-metal alloy nanozymes by using cytosine-rich hairpin-shaped DNA structures as growth templates. DNA-Ag@Pd NCs exhibit high photothermal conversion efficiency (59.32%) under 1270 nm laser and photothermally augmented peroxidase-mimicking activity with synergetic enhancement between Ag and Pd. In addition, hairpin-shaped DNA structures on the surface of DNA-Ag@Pd NCs endow them with good stability and biocompatibility in vitro and in vivo, and enhanced permeability and retention effect at tumor sites. Upon intravenous injection, DNA-Ag@Pd NCs demonstrate high-contrast NIR-II photoacoustic imaging-guided efficient photothermal-augmented NCT of gastric cancer. This work provides a strategy to synthesize versatile noble-metal alloy nanozymes in a bioinspired way for highly efficient therapy of tumors.

Analysis of a machine learning-based risk stratification scheme for acute kidney injury in vancomycin.

Vancomycin-associated acute kidney injury (AKI) continues to pose a major challenge to both patients and healthcare providers. The purpose of this study is to construct a machine learning framework for stratified predicting and interpreting vancomycin-associated AKI. Our study is a retrospective analysis of medical records of 724 patients who have received vancomycin therapy from 1 January 2015 through 30 September 2020. The basic clinical information, vancomycin dosage and days, comorbidities and medication, laboratory indicators of the patients were recorded. Machine learning algorithm of XGBoost was used to construct a series risk prediction model for vancomycin-associated AKI in different underlying diseases. The vast majority of sub-model performed best on the corresponding sub-dataset. Additionally, the aim of this study was to explain each model and to explore the influence of clinical variables on prediction. As the results of the analysis showed that in addition to the common indicators (serum creatinine and creatinine clearance rate), some other underappreciated indicators such as serum cystatin and cumulative days of vancomycin administration, weight and age, neutrophils and hemoglobin were the risk factors for cancer, diabetes mellitus, heptic insufficiency respectively. Stratified analysis of the comorbidities in patients with vancomycin-associated AKI further confirmed the necessity for different patient populations to be studied.

Network pharmacology and molecular docking reveal the effective substances and active mechanisms of Dalbergia Odoriferain protecting against ischemic stroke.

Dalbergia Odorifera (DO) has been widely used for the treatment of cardiovascular and cerebrovascular diseasesinclinical. However, the effective substances and possible mechanisms of DO are still unclear. In this study, network pharmacology and molecular docking were used toelucidate the effective substances and active mechanisms of DO in treating ischemic stroke (IS). 544 DO-related targets from 29 bioactive components and 344 IS-related targets were collected, among them, 71 overlapping common targets were got. Enrichment analysis showed that 12 components were the possible bioactive components in DO, which regulating 9 important signaling pathways in 3 biological processes including 'oxidative stress' (KEGG:04151, KEGG:04068, KEGG:04915), 'inflammatory response'(KEGG:04668, KEGG:04064) and 'vascular endothelial function regulation'(KEGG:04066, KEGG:04370). Among these, 5 bioactive components with degree≥20 among the 12 potential bioactive components were selected to be docked with the top5 core targets using AutodockVina software. According to the results of molecular docking, the binding sites of core target protein AKT1 and MOL002974, MOL002975, and MOL002914 were 9, 8, and 6, respectively, and they contained 2, 1, and 0 threonine residues, respectively. And some binding sites were consistent, which may be the reason for the similarities and differences between the docking results of the 3 core bioactive components. The results of in vitro experiments showed that OGD/R could inhibit cell survival and AKT phosphorylation which were reversed by the 3 core bioactive components. Among them, MOL002974 (butein) had a slightly better effect. Therefore, the protective effect of MOL002974 (butein) against cerebral ischemia was further evaluated in a rat model of middle cerebral artery occlusion (MCAO) by detecting neurological score, cerebral infarction volume and lactate dehydrogenase (LDH) level. The results indicated that MOL002974 (butein) could significantly improve the neurological score of rats, decrease cerebral infarction volume, and inhibit the level of LDH in the cerebral tissue and serum in a dose-dependent manner. In conclusion, network pharmacology and molecular docking predicate the possible effective substances and mechanisms of DO in treating IS. And the results are verified by the in vitro and in vivo experiments. This research reveals the possible effective substances from DO and its active mechanisms for treating IS and provides a new direction for the secondary development of DO for treating IS.

Synthetic Lipopeptide Enhances Protective Immunity Against Helicobacter pylori Infection.

Over fifty percent of the people around the world is infected with Helicobacter pylori (H. pylori), which is the main cause of gastric diseases such as chronic gastritis and stomach cancer. H. pylori adhesin A (HpaA), which is a surface-located lipoprotein, is essential for bacterial colonization in the gastric mucosa. HpaA had been proposed to be a promising vaccine candidate against H. pylori infection. However, the effect of non-lipidated recombinant HpaA (rHpaA) to stimulate immune response was not very ideal, and the protective effect against H. pylori infection was also limited. Here, we hypothesized that low immunogenicity of rHpaA may attribute to lacking the immunostimulatory properties endowed by the lipid moiety. In this study, two novel lipopeptides, LP1 and LP2, which mimic the terminal structure of the native HpaA (nHpaA), were synthesized and TLR2 activation activity was confirmed in vitro. To investigate whether two novel lipopeptides could improve the protective effect of rHpaA against the infection of H. pylori, groups of mice were immunized either intramuscularly or intranasally with rHpaA together with LP1 or LP2. Compared with rHpaA alone, the bacterial colonization of the mice immunized with rHpaA plus LP2 via intranasal route was significantly decreased and the expression levels of serum IgG2a, IFN-γ, and IL-17 cytokines in spleen lymphocyte culture supernatant increased obviously, indicating that the enhanced protection of LP2 may be associated with elevated specific Th1 and Th17 responses. In conclusion, LP2 has been shown to improve the protective effect of rHpaA against H. pylori infection, which may be closely related to its ability in activating TLR2 by mimicking the terminal structure of nHpaA.

Aloe-Emodin Ameliorates Renal Fibrosis Via Inhibiting PI3K/Akt/mTOR Signaling Pathway In Vivo and In Vitro.

Fibrosis is the major pathological feature of chronic kidney disease (CKD). Aloe-emodin (AE), one of the main active compounds in Rhubarb, is widely used for renal protection. However, mechanisms implied in the modulation of kidney fibrosis after AE treatment for CKD remain elusive. Here, we explored the protective effects of AE for renal fibrosis and the involved mechanisms in vivo and in vitro. The renal fibrosis mice model was established by unilateral ureteral obstruction (UUO). We found that AE administration significantly ameliorated UUO-induced impairment of kidney, evidenced by improved histopathological abnormalities, body weight, and abnormal renal function in mice model. Immunohistochemical staining showed that TGF-ß1 and Fibronectin expressions were significantly decreased in UUO mice compared with sham group. Meanwhile, we found that AE suppressed the activation of the PI3K/Akt/mTOR pathway induced by TGF-ß1 in vivo. AE improved cell survival and decreased the level of fibrosis-related proteins under TGF-ß1-induced fibrosis in HK-2 cells as well as in vitro. Furthermore, both wortmannin, an inhibitor of PI3K, and short-hairpin RNAs of PI3K knockdown abrogated TGF-ß1-induced phosphorylation of Akt and mTOR, and decreased the suppression of fibrosis. These findings indicated that AE alleviated fibrosis by inhibiting PI3K/Akt/mTOR pathway in vivo and in vitro, which may provide a potential therapeutic option for CKD.

Cardioprotective effects and underlying mechanism of Radix Salvia miltiorrhiza and Lignum Dalbergia odorifera in a pig chronic myocardial ischemia model.

Traditional Chinese medicines, including Radix Salvia miltiorrhiza (SM) and Lignum Dalbergia odorifera (DO) extracts, have historically been used to treat myocardial ischemia and other cardiovascular diseases. The volatile oil of DO (DOO) is one of the main components of DO. The aim of the present study was to assess the cardioprotective effects and possible underlying mechanisms of SM­DOO in pigs with ameroid constriction­induced chronic myocardial ischemia. An ameroid constrictor was placed around the left anterior descending coronary artery of pigs to induce chronic myocardial ischemia. At weeks 2, 6 and 8, myocardial injury markers and blood gas levels were detected. At week 8, coronary angiography, echocardiography and hemodynamics analysis were performed to evaluate myocardial function. Following sacrifice, myocardial tissue was collected and subjected to morphological, histopathological and apoptosis assays. Western blotting was used to detect the protein expression of Bcl­2 associated X (Bax), Bcl­2, Akt, phosphorylated (p)­Akt, glycogen synthase kinase (GSK)­3ß and p­GSK­3ß. It was revealed that SM­DOO treatment following chronic myocardial ischemia significantly downregulated the expression of myocardial injury markers, ameliorated myocardial oxygen consumption, increased collateralization, reduced regional cardiac dysfunction and limited the extent of myocardial damage. Furthermore, the results of an apoptosis assay revealed that the apoptosis rate was decreased, the expression of Bax decreased and Bcl­2 increased, and the ratio of Bcl­2/Bax was increased. Further experiments indicated that treatment with SM­DOO increased the phosphorylation of Akt and GSK­3ß. These findings suggest that SM­DOO treatment ameliorates myocardial injury in a chronic myocardial ischemia model, and that the underlying mechanisms responsible may be associated with the activation of the Akt/GSK­3ß signal pathway. Thus, experimental evidence that SM­DOO may be an effective drug for the prevention and treatment of chronic myocardial ischemia in clinical applications has been provided.

Beneficial effects of extracts from Lucilia sericata maggots on burn wounds in rats.

Lucilia sericata maggots have beneficial properties; however, their protective effects on burn wounds have yet to be fully elucidated. In the present study, a deep second­degree burn rat model was used to investigate the burn wound healing properties of aqueous extract of maggots (MAE). The anti­inflammatory, antioxidative and antibacterial activities were examined. In addition, the protein expression levels of Akt, vascular endothelial growth factor A (VEGFA) and nuclear factor­κB (NF­κB) were detected by western blotting. The findings of the present study revealed that MAE treatment increased burn wound healing and hydroxyproline content in the burn­treated rats. A total of seven compounds (MAE­P1­P7) were separated from MAE and a comparative study was performed to identify the major active component. The results demonstrated that MAE­P6 exerted greater antibacterial activity compared with the other compounds. MAE­P6 treatment reduced tissue levels of malondialdehyde, tumor necrosis factor­α and interleukin­6, and increased superoxide dismutase activity. Furthermore, MAE­P6 increased the expression levels of VEGFA and reduced NF­κB expression through Akt, which was verified by treatment with the Akt­specific inhibitor, LY294002. In conclusion, the present study demonstrated that the beneficial effects of MAE on burn wound healing were due to its antibacterial, antioxidative and anti­inflammatory activities. MAE­P6 reduced the release of inflammatory cytokines via the Akt/NF­κB signaling pathway, and regulated angiogenesis and vasopermeability via the Akt/VEGFA pathway.

Danshensu accelerates angiogenesis after myocardial infarction in rats and promotes the functions of endothelial progenitor cells through SDF-1α/CXCR4 axis.

The present study was performed to investigate the potential role of Danshensu in therapeutic angiogenesis in ischemic myocardium and endothelial progenitor cells (EPCs) function. The rat model of myocardial infarction (MI) injury was induced by left anterior descending coronary artery ligation for 14 days. Danshensu significantly alleviated myocardial ischemia injury by ameliorating left ventricular function and reducing infarct size. Furthermore, Danshensu potentiated post-ischemia neovascularization as evidenced by increased microvessel density in infarction boundary zone, as well as the expression of marker proteins vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Moreover, Danshensu notably promoted stromal cell-derived factor-1α (SDF-1α) level in plasma and C-X-C chemokine receptor type 4 (CXCR4) expression in peri-infarction myocardium, and AMD3100 (CXCR4 antagonist) could reverse the angiogenic and cardioprotective effects of Danshensu. For in vitro study, EPCs were isolated from bone marrow of rats. On the one hand, Danshensu provided significant cytoprotection against hypoxia insult by boosting EPCs viability and inhibiting apoptosis, and upregulated Akt phosphorylation. On the other hand, Danshensu enhanced proangiogenic functions of EPCs on cell migration and tube formation, and increased SDF-1α and CXCR4 expression. Likewise, the cytoprotection and proangiogenic functions of Danshensu on EPCs were partly negated by LY294002 (PI3K antagonist) and CXCR4 siRNA, respectively. Taken together, our results suggested that the cardioprotection of Danshensu in MI rats may be related to promoting myocardial neovascularization. The possible mechanisms may involve improving EPCs survival in hypoxia condition through Akt phosphorylation, and accelerating EPCs proangiogenic functions through SDF-1α/CXCR4 axis.

Cardioprotective effects and mechanism of Radix Salviae miltiorrhizae and Lignum Dalbergiae odoriferae on rat myocardial ischemia/reperfusion injury.

Radix Salviae miltiorrhizae (SM) and Lignum Dalbergiae odoriferae (DO) are traditional Chinese medicinal herbs used to treat ischemic heart disease and other cardiovascular diseases; however, to the best of our knowledge, there are currently few studies regarding their effects. The present study aimed to investigate the cardioprotective effects of SM and DO during myocardial ischemia/reperfusion (MI/R) injury in rats, and explore the molecular mechanisms that underlie their actions. In the present study, Sprague­Dawley rats were pretreated with SM, the aqueous extract of DO (DOA) and the volatile oil of DO (DOO), either as a monotherapy or in combination for 7 days. Subsequently, the rats were subjected to 30 min of ischemia followed by 180 min of reperfusion. Traditional pharmacodynamic evaluation and metabonomics based on gas chromatography/time­of­flight mass spectrometry were used to identify the therapeutic effects of these traditional Chinese medicines. The results revealed that SM, DOA and DOO monotherapies ameliorated cardiac function, and this effect was strengthened further when used in combined therapies. Among the combined treatments, SM + DOO exhibited the greatest potential (P<0.05) to improve electrocardiogram results and heart rate, reduce the heart weight index and myocardial infarct size, and decrease the levels of creatine kinase­MB and lactate dehydrogenase. In addition, metabonomics­based findings, including the principal component analysis and partial least squares discriminant analysis score plot of the metabolic state in rat serum, provided confirmation for the aforementioned results, verifying that SM + DOO exerted synergistic therapeutic efficacies to exhibit a greater effect on rats with MI/R injury when compared with the other pretreatment groups. Furthermore, the most effective duration of SM + DOO treatment was 30 min and the least effective duration was 180 min. Treatment with SM + DOO also significantly (P<0.01) reduced the number of terminal deoxynucleotidyl transferase­mediated dUTP nick end­labeling­positive cells, tumor necrosis factor­α andinterleukin­6 expression, and malondialdehyde content, and increased the serum and tissue activity of superoxide dismutase. These results indicated that the combined effects of SM + DOO may be more effective compared with the single pretreatments against MI/R injury in rats. This effect may be achieved partly through anti­apoptotic, antioxidant and anti­inflammatory activities. Therefore, SM + DOO may be considered an effective and promising novel strategy for the prophylaxis and treatment of ischemic heart disease.

Protective effect of butin against ischemia/reperfusion-induced myocardial injury in diabetic mice: involvement of the AMPK/GSK-3ß/Nrf2 signaling pathway.

Hyperglycemia-induced reactive oxygen species (ROS) generation contributes to development of diabetic cardiomyopathy (DCM). This study was designed to determine the effect of an antioxidant butin (BUT) on ischemia/reperfusion-induced myocardial injury in diabetic mice. Myocardial ischemia/reperfusion (MI/R) was induced in C57/BL6J diabetes mice. Infarct size and cardiac function were detected. For in vitro study, H9c2 cells were used. To clarify the mechanisms, proteases inhibitors or siRNA were used. Proteins levels were investigated by Western blotting. In diabetes MI/R model, BUT significantly alleviated myocardial infarction and improved heart function, together with prevented diabetes-induced cardiac oxidative damage. The expression of Nrf2, AMPK, AKT and GSK-3ß were significantly increased by BUT. Furthermore, in cultured H9c2 cardiac cells silencing Nrf2 gene with its siRNA abolished the BUT's prevention of I/R-induced myocardial injury. Inhibition of AMPK and AKT signaling by relative inhibitor or specific siRNA decreased the level of BUT-induced Nrf2 expression, and diminished the protective effects of BUT. The interplay relationship between GSK-3ß and Nrf2 was also verified with relative overexpression and inhibitors. Our findings indicated that BUT protected against I/R-induced ROS-mediated apoptosis by upregulating the AMPK/Akt/GSK-3ß pathway, which further activated Nrf2-regulated antioxidant enzymes in diabetic cardiomyocytes exposed to I/R.

Molecular characterization of Beclin 1 in rare minnow (Gobiocypris rarus) and its expression after waterborne cadmium exposure.

Beclin 1 plays an important role in autophagy and apoptosis which are well documented in mammals. However, relevant reports are rare in fish. This study characterized Beclin 1 of the rare minnow Gobiocypris rarus (rmBeclin 1), which encodes a peptide of 447 amino acids using RT-PCR and RACE. The deduced peptide showed 96.4 and 80.8% similarity to Beclin 1 of common carp and human, respectively. Semiquantitative RT-PCR revealed that rmBeclin 1 was ubiquitously expressed in all tested tissues of male and female fish in all developmental stages, even unfertilized eggs. RT-qPCR revealed that rmBeclin 1 mRNA transcripts were significantly up-regulated in gills after a 12 h treatment with waterborne CdCl2 but were decreased thereafter. However, rmBeclin 1 expression was decreased in the brain, but it was not significantly changed in other tissues. Subchronic CdCl2 exposure significantly increased rmBeclin 1 in the brain, but it distinctly decreased rmBeclin 1 in the gill and hepatopancreas. A dose-dependent effect was not observed in mature fish treated for 96 h, but a dose-dependent effect existed in immature fish treated for 10 days. Longer treatment (10 day) caused a significantly higher expression of rmBeclin 1 in the larvae groups. These data suggest that alterations in rmBeclin 1 after CdCl2 exposure are tissue-specific and time-related and that the dose-dependent effect was restricted to a certain concentration range and exposure time.

[Toxic effects of CdSe/ZnS QDs to zebrafish embryos].

The toxic effects of CdSe/ZnS QDs on zebrafish (Danio rerio) embryos at different developmental stages were investigated in this study. The voluntary movement frequency, body length, hatching rate, mortality and malformation rate, SOD activities, MDA contents, mRNA expression of metallothionein (MT) and heat stress protein 70 (Hsp70) were used as indicators. The results showed that the EC50 was 316.994 nmol x L(-1) for zebrafish embryos (72 hpf) when exposed to CdSe/ZnS QDs. After the CdSe/ZnS QDs exposure, the embryos showed a significant increase in mortality and malformation rate, a decrease in hatching rate and body length, an advance in hatching time, and a changing in the spontaneous movement frequency, and many other toxic effects, such as the condensation of embryonic eggs, the formation of pericardial cysts and curvature of the spine. Moreover, it was found that the MDA contents in the embryos in CdSe/ZnS QDs groups were significantly increased, and the SOD activities were changed. In addition, the mRNA expression level of MT and Hsp70 were up-regulated. All the information suggests that exposure of CdSe/ZnS QDs can cause toxic effects on zebrafish embryos, and the effects may be related to the releasing of Cd2+, particle size and oxidative stress.

Evaluation of two polymeric blends (EVA/PLA and EVA/PEG) as coating film materials for paclitaxel-eluting stent application.

The ethylene vinyl acetate copolymer (EVA)/Poly (lactic acid) (PLA) blend and EVA/Poly (ethylene glycol) (PEG) blend were applied as the drug carrier materials for a bi-layer drug-loaded stent coating film, which consisted of a paclitaxel (PTX)-loaded layer and a drug-free EVA layer. The changes of weight and appearance of the drug-free polymeric blend films with increasing time were examined by X-ray diffraction analysis (XRD), gel permeation chromatography (GPC) tests and scanning electronic microscopy (SEM), and the results showed the degradation of PLA and the leaching of PEG from the films. The effects of PLA, PEG and drug contents on in vitro drug release were investigated, and the results demonstrated that the addition of PLA promoted the drug release while the addition of PEG almost did not. Franz cells diffusion test results indicated that the bi-layer structure successfully endowed the stent coating with the release of drug in a unidirectional fashion. The release profiles of films incorporated PTX and the mechanical performance of the film could be customized by readily adjusting the contents of the blend components. Therefore, the polymeric blends could be useful drug carrier materials for drug-loaded stent coating capable of releasing drug in a highly tunable manner.

Zero-order release of 5-fluorouracil from PCL-based films featuring trilayered structures for stent application.

A trilayered Poly(ε-caprolactone) (PCL)-based film with a coating layer (CL), a drug-storing layer (DSL) loaded with antitumor drug 5-Fluorouracil (5-FU) and a backing layer (BL) are presented for film-based stent application in malignant stricture or stenosis. V-C diffusion cells were used to investigate the drug permeability of the CL, while scanning electron microscopy (SEM) was employed for observing the microscopic architectures and morphologies. Drug release from the trilayered films exhibited a zero-order pattern, and the release process followed an 'outer-to-inner' pattern. The formation mechanism and influencing factors of the zero-order drug release pattern were in-depth elucidated, and factors affecting the drug release were also investigated. The reduction of initial drug loading in DSL slowed the drug release and diminished the zero-order release pattern. Drug permeability of the CL depended significantly on CL thickness, but not significantly on PCL molecular weight. Besides, the addition of PEG porogen in the CL accelerated the drug release by elevation of the drug permeability of CL, and the action mechanism of PEG was revealed by the PEG release test and SEM. The loading of 5-FU in the CL could lead to a two-phased release profile. This study revealed the potential of the trilayered film in controlled drug delivery to intraluminal tumor due to its highly tunable zero-order drug release.

Recent progress in nanotechnology for cancer therapy.

The application of nanotechnology significantly benefits clinical practice in cancer diagnosis, treatment, and management. Especially, nanotechnology offers a promise for the targeted delivery of drugs, genes, and proteins to tumor tissues and therefore alleviating the toxicity of anticancer agents in healthy tissues. This article reviews current nanotechnology platforms for anticancer drug delivery, including polymeric nanoparticles, liposomes, dendrimers, nanoshells, carbon nanotubes, superparamagnetic nanoparticles, and nucleic acid-based nanoparticles [DNA, RNA interference (RNAi), and antisense oligonucleotide (ASO)] as well as nanotechnologies for combination therapeutic strategies, for example, nanotechnologies combined with multidrug-resistance modulator, ultrasound, hyperthermia, or photodynamic therapy. This review raises awareness of the advantages and challenges for the application of these therapeutic nanotechnologies, in light of some recent advances in nanotechnologic drug delivery and cancer therapy.