Evaluation of protein digestibility and iodine bioavailability in raw and cooked Sargassum fusiforme (harvey) setchell using in vitro methods

PurposeSargassum fusiforme is a popular edible seaweed in coastal cities of China that contains diverse nutrients including iodine. Cooking is an effective way to improve food safety, but it can alter both the contents of elements along with speciation and bioavailability. Three common cooking methods, the soaking, steaming and boiling, were evaluated for their effects on the protein structures, protein digestibility, iodine content and iodine bioavailability of S. fusiforme.Design/methodology/approachFourier transform infrared spectroscopy was used to study the structural changes of protein, and an in vitro digestion/Caco-2 cell culture system was used to evaluate the digestibility of protein, bioaccessibility and bioavailability of iodine.FindingsBoiling and steaming altered the protein secondary structure demonstrated by increased a-helix and random coil and decreased β-sheet, which improved the in vitro protein digestibility. Iodine content was reduced by cooking, with the highest loss observed after boiling, followed by soaking and steaming, while it was found that both bioaccessibility and cellular uptake of iodine were significantly elevated by boiling and steaming using an in vitro digestion/Caco-2 cell culture system. The presence of ascorbic acid, citric acid or tyrosine was beneficial for the iodine absorption, while oxalic acid and phytic acid hindered the iodine bioavailability.Originality/valueThe present finding suggested that cooking was conducive to the digestion and absorption of iodine in S. fusiforme. In addition, different dietary factors could have a certain impact on the absorption of iodine. Results of the study are essential for improving the application value of S. fusiforme to ensure reasonable consumption of seaweeds.

A rapid and simple procedure for the isolation and cultivation of fibroblast-like cells from medaka and zebrafish embryos and fin clip biopsies

In many human diseases, the molecular pathophysiological mechanisms are not understood, which makes the development and testing of new therapeutic approaches difficult. The generation and characterization of animal models such as mice, rats, fruit flies, worms or fish offers the possibility for in detail studies of a disease’s development, its course and potential therapies in an organismal context, which considerably minimizes the risk of therapeutic side effects for patients. Nevertheless, due to the high numbers of experimental animals used in research worldwide, attempts to develop alternative test systems will help in reducing their count. In this regard, the cell culture system displays a suitable option due to its potential of delivering nearly unlimited material and the good opportunities for high-throughput studies such as drug testing. Here, we describe a quick and simple method to isolate and cultivate vital fibroblast-like cells from embryos and adults of two popular teleost model organisms, the Japanese rice fish medaka ( Oryzias latipes) and the zebrafish ( Danio rerio).

Identification and Characterization of Human Norovirus NTPase Regions Required for Lipid Droplet Localization, Cellular Apoptosis, and Interaction with the Viral P22 Protein

Human noroviruses (HuNVs) are the major agent of global gastroenteritis outbreaks. However, due to the lack of an efficient cell culture system for HuNV propagation, functions of the viral-encoded proteins in host cells are still poorly understood.

Glycometabolism regulates hepatitis C virus release

HCV cell-culture system uses hepatoma-derived cell lines for efficient virus propagation. Tumor cells cultured in glucose undergo active aerobic glycolysis, but switch to oxidative phosphorylation for energy production when cultured in galactose. Here, we investigated whether modulation of glycolysis in hepatocytes affects HCV infection. We showed HCV release, but not entry, genome replication or virion assembly, is significantly blocked when cells are cultured in galactose, leading to accumulation of intracellular infectious virions within multivesicular body (MVB). Blockade of the MVB-lysosome fusion or treatment with pro-inflammatory cytokines promotes HCV release in galactose. Furthermore, we found this glycometabolic regulation of HCV release is mediated by MAPK-p38 phosphorylation. Finally, we showed HCV cell-to-cell transmission is not affected by glycometabolism, suggesting that HCV cell-to-supernatant release and cell-to-cell transmission are two mechanistically distinct pathways. In summary, we demonstrated glycometabolism regulates the efficiency and route of HCV release. We proposed HCV may exploit the metabolic state in hepatocytes to favor its spread through the cell-to-cell transmission in vivo to evade immune response.