Effects of DDT and permethrin on rat hepatocytes cultivated in microfluidic biochips: Metabolomics and gene expression study.

Dichlorodiphenyl-trichloroethane (DDT) and permethrin (PMT) are amongst most prevalent pesticides in the environment. Although their toxicity has been extensively studied, molecular mechanisms and metabolic effects remain unclear, including in liver where their detoxification occurs. Here, we used metabolomics, coupled to RT-qPCR analysis, to examine effects of DDT and PMT on hepatocytes cultivated in biochips.

A simple protocol for attenuating the auto-fluorescence of cyanobacteria for optimized fluorescence in situ hybridization (FISH) imaging.

Cyanobacteria contain pigments, which generate auto-fluorescence that interferes with fluorescence in situ hybridization (FISH) imaging of cyanobacteria. We describe simple chemical treatments using CuSO4 or H2O2 that significantly reduce the auto-fluorescence of Microcystis strains. These protocols were successfully applied in FISH experiments using 16S rRNA specific probes and filamentous cyanobacteria.

Multiparametric temporal analysis of the Caco-2/TC7 demonstrated functional and differentiated monolayers as early as 14 days of culture.

Reducing the differentiation period for obtaining an in vitro intestinal barrier model is required to reduce the duration and cost for drug screening assays. In this frame, the Caco-2/TC7 subclone differentiation state was investigated from day 0 (D0) to day 32 (D32). As such, the expression of 45 genes (including cell junction, cell polarization, cell functionality, drug transport and metabolism genes) was followed throughout the 32 days.

Development of a new microfluidic platform integrating co-cultures of intestinal and liver cell lines.

We developed a new biological model to mimic the organ-organ interactions between the intestine and the liver. We coupled polycarbonate cell culture inserts and microfluidic biochips in an integrated fluidic platform allowing dynamic co-cultures (called IIDMP for Integrated Insert in a Dynamic Microfluidic Platform). The intestinal compartment was simulated using Caco-2 TC7 cells and the liver one by HepG2 C3A.

Transcriptomic comparison of cyanotoxin variants in a human intestinal model revealed major differences in oxidative stress response: effects of MC-RR and MC-LR on Caco-2 cells.

Microcystins (MCs) are cyclic hepatotoxins produced by various species of cyanobacteria. Their structure includes two variable amino acids (AA) giving rise to more than 90 MC variants, however most of the studies to date have focused on the most toxic variant: microcystin LR (MC-LR). Ingestion is the major route of human exposure to MCs and several in vivo studies have demonstrated macroscopic effects on the gastro-intestinal tract.