Protective Effect of Orbitides from Linseed (Linum usitatissimum L.) against Ultraviolet B-induced Photoaging in Zebrafish

Excessive ultraviolet (UV) exposure is the primary environmental factor that contributes to skin aging. Orbitides have been considered as important functional components in linseed, and they are complex and multiple. In this study, linseed orbitides (LOs) were divided into oxidized linseed orbitides (OLOs) and reduced linseed orbitides (RLOs) and used to investigate protection against ultraviolet B-induced photoaging in zebrafish. First, the results of the zebrafish embryo acute toxicity test showed that the OLOs had obvious embryo toxicity compared with RLOs. And RLOs had better effect in ultraviolet B-treated zebrafish, which may significantly reduce the reactive oxygen species levels and inhibit the degradation of collagen. Besides, we also found that RLOs could effectively inhibit the oxidation of proteins and lipids and regulate the activity of antioxidant enzymes. Furthermore, neutrophil recruitment to the dorsal and caudal fin regions was observed in UVB-treated zebrafish, and RLOs effectively alleviated this migration. In conclusion, RLOs have strong photoprotective effects and potential to be used as antiphotoaging ingredients.     

Toxicity of graphene oxide and multi-walled carbon nanotubes against human cells and zebrafish

Graphene possesses unique physical and chemical properties, which have inspired a wide range of potential biomedical applications. However, little is known about the adverse effects of graphene on the human body and ecological environment. The purpose of our work is to make assessment on the toxicity of graphene oxide (GO) against human cell line (human bone marrow neuroblastoma cell line and human epithelial carcinoma cell line) and zebrafish (Danio rerio) by comparing the toxic effects of GO with its sister, multi-walled carbon nanotubes (MWNTs). The results show that GO has a moderate toxicity to organisms since it can induce minor (about 20%) cell growth inhibition and slight hatching delay of zebrafish embryos at a dosage of 50 mg/L, but did not result in significant increase of apoptosis in embryo, while MWNTs exhibit acute toxicity leading to a strong inhibition of cell proliferation and serious morphological defects in developing embryos even at relatively low concentration of 25 mg/L. The distinctive toxicity of GO and MWNTs should be ascribed to the different models of interaction between nanomaterials and organisms, which arises from the different geometric structures of nanomaterials. Collectively, our work suggests that GO does actual toxicity to organisms posing potential environmental risks and the result is also shedding light on the geometrical structure-dependent toxicity of graphitic nanomaterials.     

In Vivo Toxicity Evaluation of Sugar Adulterated Heterotrigona itama Honey Using Zebrafish Model

Honey is prone to be adulterated through mixing with sugars, cheap and low-quality honey, and other adulterants. Consumption of adulterated honey may cause several health issues such as weight gain, diabetes, and liver and kidney dysfunction. Therefore, studying the impact of consumption of adulterated honey on consumers is critical since there is a lack of study in this field. Hence, the aims of this paper were: (1) to determine the lethal concentration (LC₅₀) of adulterated honey using zebrafish embryo, (2) to elucidate toxicology of selected adulterated honey based on lethal dose (LD₅₀) using adult zebrafish, (3) to determine the effects of adulterated honey on histological changes of zebrafish, and (4) to screen the metabolites profile of adulterated honey by using zebrafish blood serum. The LC₅₀ of Heterotrigona itama honey (acacia honey) and its sugar adulterants (light corn sugar, cane sugar, inverted sugar, and palm sugar in the proportion of 1–3% (w/w) from the total volume) was determined by the toxicological assessment of honey samples on zebrafish embryos (different exposure concentrations in 24, 48, 72, and 96 h postfertilization (hpf)). Pure H. itama honey represents the LC₅₀ of 34.40 ± 1.84 (mg/mL) at 96 hpf, while the inverted sugar represents the lowest LC₅₀ (5.03 ± 0.92 mg/mL) among sugar adulterants. The highest concentration (3%) of sugar adulterants were used to study the toxicology of adulterated honey using adult zebrafish in terms of acute, prolong-acute, and sub-acute tests. The results of the LD₅₀ from the sub-acute toxicity test of pure H. itama honey was 2.33 ± 0.24 (mg/mL). The histological studies of internal organs showed a lesion in the liver, kidney, and spleen of adulterated treated-honey groups compared to the control group. Furthermore, the LC-MS/MS results revealed three endogenous metabolites in both the pure and adulterated honey treated groups, as follows: (1) S-Cysteinosuccinic acid, (2) 2,3-Diphosphoglyceric acid, and (3) Cysteinyl-Tyrosine. The results of this study demonstrated that adulterated honey caused mortality, which contributes to higher toxicity, and also suggested that the zebrafish toxicity test could be a standard method for assessing the potential toxicity of other hazardous food additives. The information gained from this research will permit an evaluation of the potential risk associated with the consumption of adulterated compared to pure honey.     

Synthesis,Culture Medium Stability,and In Vitro and In Vivo Zebrafish Embryo Toxicity of Metal–Organic Framework Nanoparticles

Metal–organic frameworks (MOFs) are among the most attractive porous materials available today. They have garnered much attention for their potential utility in many different areas such as gas storage, separation, catalysis, and biomedicine. However, very little is known about the possible health or environmental risks of these materials. Here, the results of toxicity studies on sixteen representative uncoated MOF nanoparticles (nanoMOFs), which were assessed for cytotoxicity to HepG2 and MCF7 cells in vitro, and for toxicity to zebrafish embryos in vivo, are reported. Interestingly, there is a strong correlation between their in vitro toxicity and their in vivo toxicity. NanoMOFs were ranked according to their respective in vivo toxicity (in terms of the amount and severity of phenotypic changes observed in the treated zebrafish embryos), which varied widely. Altogether these results show different levels of toxicity of these materials; however, leaching of solubilized metal ions plays a main role.     

Biocompatible copper(I) catalysts for in vivo imaging of glycans

The Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is the standard method for bioorthogonal conjugation. However, current Cu(I) catalyst formulations are toxic, hindering their use in living systems. Here we report that BTTES, a tris(triazolylmethyl)amine-based ligand for Cu(I), promotes the cycloaddition reaction rapidly in living systems without apparent toxicity. This catalyst allows, for the first time, noninvasive imaging of fucosylated glycans during zebrafish early embryogenesis. We microinjected embryos with alkyne-bearing GDP-fucose at the one-cell stage and detected the metabolically incorporated unnatural sugars using the biocompatible click chemistry. Labeled glycans could be imaged in the enveloping layer of zebrafish embryos between blastula and early larval stages. This new method paves the way for rapid, noninvasive imaging of biomolecules in living organisms.     

Biocompatibility Study of Curcumin-Loaded Pluronic F127 Nanoformulation (NanoCUR) against the Embryonic Development of Zebrafish (Danio rerio)

Curcumin (CUR) has been studied for its biomedical applications due to its active biological properties. However, CUR has limitations such as poor solubility, low bioavailability, and rapid degradation. Thus, CUR was nanoformulated with the application of polymeric micelle. Previous studies of CUR-loaded Pluronic F127 nanoformulation (NanoCUR) were generally prioritized toward cancer cells and its therapeutic values. There are reports that emphasize the toxicity of CUR, but reports on the toxicity of NanoCUR on embryonic developmental stages is still scarce. The present study aims to investigate the toxicity effects of NanoCUR on the embryonic development of zebrafish (Danio rerio). NanoCUR was synthesized via thin film hydration method and then characterized using DLS, UV-Vis, FTIR, FESEM, and XRD. The toxicity assessment of NanoCUR was conducted using zebrafish embryos, in comparison to native CUR, as well as Pluronic F127 (PF) as the controls, and ROS assay was further carried out. It was revealed that NanoCUR showed an improved toxicity profile compared to native CUR. NanoCUR displayed a delayed toxicity response and showed a concentration- and time-dependent toxicity response. NanoCUR was also observed to generate a significantly low reactive oxygen species (ROS) compared to native CUR in ROS assay. Overall, the results obtained highlight the potential of NanoCUR to be developed in clinical settings due to its improved toxicity profile compared to CUR.     

Positively charged liposomes consisting of the KTTKS pentapeptide conjugated with rhodamine increase rhodamine toxicity in E. coli and zebrafish embryo

Liposomes composed of cell‐penetrating peptide derivatives increased transport across the cell membrane. Conjugating rhodamine to a cell‐penetrating peptide increased the toxicity of rhodamine in E. coli and zebrafish embryos. A similar total protein inhibition pattern with different intensities, indicating that the interaction pathways of the rho‐KTTKS‐CONH₂ monomer and liposomes were the same. It suggests that the rho‐KTTKS‐CONH₂ liposomes showed higher toxicity because better transport across the cell membrane increased the effective concentration inside cells. The staining of zebrafish embryos using rho‐KTTKS‐CONH₂ liposomes showed a longer retention time, suggesting that it can penetrate deeper tissues or organs in zebrafish.     

Synthesis of a new fluorescent small molecule probe and its use for in vivo lipid imaging

A new small molecule probe for in vivo lipid imaging, LipidGreen (compound 5), was developed. LipidGreen stained lipid droplets in 3T3L1 cell lines and fat deposits in zebrafish without apparent toxicity up to 100 μM. The utility of LipidGreen as a drug screening platform for fat regulation was also demonstrated in live zebrafish.     

Study on the Joint Toxicity of BPZ,BPS, BPC and BPF to Zebrafish

Bisphenol Z (BPZ), bisphenol S (BPS), bisphenol C (BPC), and bisphenol F (BPF) had been widely used as alternatives to bisphenol A (BPA), but the toxicity data of these bisphenol analogues were very limited. In this study, the joint toxicity of BPZ, BPS, BPC, and BPF to zebrafish (Danio rerio) was investigated. The median half lethal concentrations (LC50) of BPZ, BPS, BPC, and BPF to zebrafish for 96 h were 6.9 × 10⁵ µM, 3.9 × 10⁷ µM, 7.1 × 10⁵ µM, and1.6 × 10⁶ µM, respectively. The joint toxicity effect of BPF–BPC (7.7 × 10⁵–3.4 × 10⁵µM) and BPZ–BPC (3.4 × 10⁵–3.5 × 10⁵µM) with the same toxic ratio showed a synergistic effect, which may be attributed to enzyme inhibition or induction theory. While the toxicity effect of the other two bisphenol analogue combined groups and multi-joint pairs showed an antagonistic effect due to the competition site, other causes need to be further explored. Meanwhile, the expression levels of the estrogen receptor genes (ERα, ERβ1) and antioxidant enzyme genes (SOD, CAT, GPX) were analyzed using a quantitative real-time polymerase chain reaction in zebrafish exposure to LC₅₀ of BPZ, BPS, BPC, and BPF collected at 24, 48, 72, and 96 h. Relative expression of CAT, GPX, and ERβ1 mRNA declined significantly compared to the blank control, which might be a major cause of oxidant injury of antioxidant systems and the disruption of the endocrine systems in zebrafish.     

The Antiproliferative and Apoptotic Effect of a Novel Synthesized S-Triazine Dipeptide Series,and Toxicity Screening in Zebrafish Embryos

Several derivatives containing morpholine/piperidine, anilines, and dipeptides as pending moieties were prepared using s-triazine as a scaffold. These compounds were evaluated for their anticancer activity against two human breast cancer cell lines (MCF-7 and MDA-MB-231), a colon cancer cell line (HCT-116), and a non-tumorigenic cell line (HEK 293). Tamoxifen was used as a reference. Animal toxicity tests were carried out in zebrafish embryos. Most of these compounds showed a higher activity against breast cancer than colon cancer. Compound 3a—which contains morpholine, aniline, and glycylglycinate methyl ester—showed a high level of cytotoxicity against MCF-7 cells with IC₅₀ values of less than 1 µM. This compound showed a much lower level of toxicity against the non-tumorigenic HEK-293 cell line, and in the in vivo studies using zebrafish embryos. Furthermore, it induced cell cycle arrest at the G2/M phase, and apoptosis in MCF-7 cells. On the basis of our results, 3a emerges as a potential candidate for further development as a therapeutic drug to treat hormone receptor-positive breast cancer.     

Novel Pyridyl–Oxazole Carboxamides: Toxicity Assay Determination in Fungi and Zebrafish Embryos

Eight novel pyridyl–oxazole carboxamides were evaluated against fungi and displayed good fungicidal activities against Botrytis cinereal and Rhizoctonia solani. Preliminary bioassay results indicated that at 100 mg/L, compounds 6a–6e, 6g and 6h exhibited 100% fungicidal activities against Botrytis cinerea, and the compound 6b to Rhizoctonia solani at 100%. Then, the zebrafish embryo acute toxicity test was performed to assess the toxicity of 6b and 6c. A series of malformations appeared, when the zebrafish embryos were exposed to 6b and 6c, such as delayed yolk sac resorption, significant shortening of body length, pericardial edema, bending spine, lack of melanin, heart hemorrhage, head hemorrhage, delayed swim sac development, yolk malformation and head malformation. In addition, the acute toxicity of 6b to zebrafish embryo is 4.878 mg/L, and 6c is 6.257 mg/L.     

ALDH2 Mediates 5-Nitrofuran Activity in Multiple Species

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Highlights? Zebrafish provide a viable assay for the biological toxicity of 5-nitrofurans ? ALDH2 inhibitors prevent 5-nitrofuran toxicity in zebrafish and yeast ? Genetic dependence on ALDH2 for 5-nitrofuran toxicity in zebrafish and yeast systems ? 5-Nitrofurans bind to and are substrates of human ALDH2     

益母草碱类似物设计、合成及其Na+/H+交换器-1抑制活性

以中药益母草中有效成分益母草碱为先导化合物,按生物电子等排原理,设计合成了18个益母草碱类似物.通过MS,1H NMR,13C NMR对化合物结构进行表征.初步的药效研究结果表明部分化合物具有Na+/H+交换器-1 (NHE-1)抑制活性,其中化合物1a和1e的活性显著强于阳性对照药Cariporide.     

Evaluation of the toxic effect on zebrafish (Danio rerio) exposed to uranium mill tailings leaching solution

The objective of this study was to evaluate the potential ecological danger and toxic effect of uranium mill tailings leaching solution (UMTLS) on aquatic animals. UMTLS was identified to contain two radioactive elements, nine heavy metal elements, and five non-metallic materials. The acute toxicity test indicated that the 1, 12, 24, 48, 72, 96 h LC₅₀ values of UMTLS to the zebrafish were 12.1, 7.1, 4.4, 3.8, 3.4, and 2.9%, respectively. In sub-lethal toxicity tests, superoxide dismutase, catalase, Na⁺–K⁺–ATPase activities, and malondialdehyde content were respectively determined and analyzed in the zebrafish gill, gonad, muscle, and liver after exposed to four different concentration levels of UMTLS for 7 and 14 days, respectively. The result showed that the most sensitivity of the antioxidant system in zebrafish tissues in UMTLS was gill, and then decreased in gonad, muscle and liver respectively. Na⁺–K⁺–ATPase activity in the liver and gonad may be considered as a reference biomarker of UMTLS stress. The data in this study may be valuable that the toxicity of such as the leaching solution of potentially hazardous material was compared with that of each constituent.     

AT1受体的中药活性成分筛选模型及其作用机理研究

传统中药对治疗心血管类疾病疗效显著,例如钩藤、黄芪、益母草等在临床应用广泛.现代药理研究表明钩藤碱可以降压;黄芪中毛蕊异黄酮能舒张血管平滑肌、保护心脑血管;益母草碱可扩张微血管,改善血液流变异常,但它们分子层面作用机制尚不明确.首先以牛视紫红质蛋白为模板,模建出心血管疾病主要靶点AT1受体的三维结构.然后将AT1受体拮抗剂和中药活性成分与受体模型结合的作用方式进行了对比研究,据此提出了中药活性成分治疗心血管疾病的作用机理,并建立了AT1受体的中药活性成分筛选模型.结果表明:黄芪毛蕊异黄酮等中药活性成分能与AT1受体活性口袋中的残基发生氢键作用,结合方式与AT1受体拮抗剂相似.每一种AT1受体拮抗剂均与His183,Lys199,His256,Gln257,Ser105,Ser109,Tyr113,Asn200中多个发生氢键作用;黄芪毛蕊异黄酮与Try113,Lys199,Gln257,Ser105发生氢键作用.本研究从分子层面上阐释了一些中药活性小分子的治病机理,为进一步挖掘中药资源,研究AT1受体相关的心脑血管类药物,合理设计和筛选AT1受体的拮抗剂提供重要依据.     

Synthesis and antiangiogenic activity of novel gambogic acid derivatives

Gambogic acid (GA) is in a phase II clinical trial as an antitumor and antiangiogenesis agent. In this study, 36 GA derivatives were synthesized and screened in a zebrafish model to evaluate their antiangiogenic activity and toxicity. Derivatives 4, 32, 35, 36 effectively suppressed the formation of newly grown blood vessels and showed lower toxicities than GA as evaluated by zebrafish heart rates and mortalities. They also exhibited more potent migration and HUVEC tube formation inhibiting activities than GA. Among them, 36 was the most potent one, suggesting that it may serve as a potential new antiangiogenesis candidate with low toxicity. Additionally, 36 showed comparable antiproliferative activity to HUVECs and five tumor cell lines but low cytotoxicity to LO2 cells.     

In vivo monitoring of mercury ions using a rhodamine-based molecular probe

Exposure to mercury causes severe damage to various tissues and organs in humans. Concern over mercury toxicity has encouraged the development of efficient, sensitive, and selective methods for the in vivo detection of mercury. Although a variety of chemosensors have been exploited for this purpose, no in vivo monitoring systems have been described to date. In this report, we describe an irreversible rhodamine chemosensor-based, real-time monitoring system to detect mercury ions in living cells and, in particular, vertebrate organisms. The chemosensor responds rapidly, irreversibly, and stoichiometrically to mercury ions in aqueous media at room temperature. The results of experiments with mammalian cells and zebrafish show that the mercury chemosensor is cell and organism permeable and that it responds selectively to mercury ions over other metal ions. In addition, real-time monitoring of mercury-ion uptake by cells and zebrafish using this chemosensor shows that saturation of mercury-ion uptake occurs within 20-30 min in cells and organisms. Finally, accumulation of mercury ions in zebrafish tissue and organs is readily detected by using this rhodamine-based chemosensor.     

Anti-Tumor Active Isopropylated Fused Azaisocytosine-Containing Congeners Are Safe for Developing Danio rerio as Well as Red Blood Cells and Activate Apoptotic Caspases in Human Breast Carcinoma Cells

New isopropylated fused azaisocytosine-containing congeners (I–VI) have previously been reported as promising anticancer drug candidates, so further research on these molecules in the preclinical development phase is fully justified and necessary. For this reason, in the present paper, we assess the toxicity/safety profiles of all the compounds using Danio rerio and red blood cell models, and examine the effect of the most selective congeners on the activation of apoptotic caspases in cancer and normal cells. In order to evaluate the effect of each molecule on the development of zebrafish embryos/larvae and to select the safest compounds for further study, various phenotypic parameters (i.e., mortality, hatchability, heart rate, heart oedema, yolk sac utilization, swim bladder development and body shape) were observed, and the half maximal lethal concentration, the maximal non-lethal concentration and no observed adverse effect concentration for each compound were established. The effect of all the isopropylated molecules was compared to that of an anticancer agent pemetrexed. The lipophilicity-dependent structure–toxicity correlations were also determined. To establish the possible interaction of the compounds with red blood cells, an ex vivo hemolysis test was performed. It was shown that almost all of the investigated isopropylated congeners have no adverse phenotypic effect on zebrafish development during five-day exposure at concentrations up to 50 μM (I–III) or up to 20 μM (IV–V), and that they are less toxic for embryos/larvae than pemetrexed, demonstrating their safety. At the same time, all the molecules did not adversely affect the red blood cells, which confirms their very good hemocompatibility. Moreover, they proved to be activators of apoptotic caspases, as they increased caspase-3, -7 and -9 levels in human breast carcinoma cells. The conducted research allows us to select—from among the anticancer active drug candidates—compounds that are safe for developing zebrafish and red blood cells, suitable for further in vivo pharmacological tests.