ß-Carotene extracted from Blakeslea trispora attenuates oxidative stress, inflammatory, hepatic injury and immune damage induced by copper sulfate in zebrafish (Danio rerio).

ß-Carotene, as a kind of potent antioxidant compounds, has gained extensive attention. Blakeslea trispora, a filiform aerobic fungus, has been proposed as a natural source of ß-carotene for commercial exploitation. However, it has not yet been investigated whether ß-carotene extracted from Blakeslea trispora can attenuate oxidative stress, inflammatory, liver injury and immune damage of zebrafish (Danio rerio) exposed to copper sulfate (CuSO4). In this study, we evaluated the effects of ß-carotene on migration of GFP-labeled neutrophils, histological changes of liver, markers of oxidative, inflammatory cytokines and transaminase analysis, as well as the expression and activities of apoptosis, immune-related certain genes in zebrafish treated with different concentrations of ß-carotene (0, 10, 20, 40 µg/mL) after exposure to CuSO4. The results indicated that ß-carotene reduced migration of neutrophils and released liver damage. What's more, ß-carotene was found to reduce the index levels of oxidative stress response (HMOX-1, reactive oxygen species (ROS), NADPH, MDA), inflammatory factors (interleukine-1ß (IL-1ß), interleukine-6 (IL-6), interleukine-8 (IL-8), tumor necrosis factor-α (TNF-α)), liver function protein (AST, ALT) which increased by CuSO4. ß-Carotene also promoted the activities of SOD, GSH-Px, ACP, AKP and LZM and increased the protein of immune-related factors, IgM and IFN-γ after exposure to CuSO4. Thus, our results demonstrate that ß-carotene has an antioxidant, anti-inflammatory and hepatoprotective activity and participation in immunoregulation.

High-throughput imaging of zebrafish embryos using a linear-CCD-based flow imaging system.

High-throughput imaging and screening is essential for biomedical research and drug discovery using miniature model organisms such as zebrafish. This study introduces a high-speed imaging system which illuminates zebrafish embryos flowing through a capillary tube with a sheet of light and captures them using a linear charge-coupled device (CCD). This system can image dozens of zebrafish embryos per second. An image algorithm was developed to recognize each embryo and to perform automatic analysis. We distinguished dead and living embryos according to the gray level distribution and conducted statistics of morphological characteristics of embryos at different growing stages.