Biology subjects

Baccaro, M.

Publications and source records attributed to Baccaro, M..

3 recordsLinked to original sources

bioRxiv2025

Gene expression profile dynamics of earthworms exposed to ZnO and ZnO:Mn nanomaterials

Zinc oxide containing nanomaterials may elicit toxic responses in environmental organisms such as earthworms. Although toxic responses in earthworms have been reported, few studies have attempted to understand the molecular mode of action dynamics explaining the observed toxicity at a transcriptional level. This study investigates the time-dependent gene expression response in earthworms exposed to ZnO nanomaterials and ZnO:Mn multicomponent nanomaterials. Earthworms were exposed to ZnO or ZnO:Mn for 7 days and to ZnO:Mn or MnCl2 for 14 days. Strong differential gene expression responses were observed after 4 days of exposure to ZnO nanomaterials and after 2 days of exposure to ZnO:Mn. Moderate differential gene expression responses were observed after 14 days of exposure to ZnO:Mn and MnCl2. Gene ontology (GO) enrichment analysis revealed that differentially expressed genes in earthworms exposed to ZnO were associated with terms such as actin, (striated) muscle cells, contractile fiber, myofibril, sarcomere and supramolecular cellular components. In addition, genes that were upregulated after 2 days of exposure to ZnO:Mn were linked to GO terms including cilium, microtubule, cell projection, axoneme and sperm flagellum cellular components. Downregulated genes were enriched to GO terms related to ribosomes, mitochondria, translation, peptide processes, respiration and oxidative phosphorylation. Finally, for earthworms exposed to ZnO:Mn and MnCl2 for 14 days, only a limited number of differentially expressed genes were involved in GO terms related to diverse biological implications. In summary, exposing earthworms to the ZnO and ZnO:Mn nanomaterials elicited a transient response in differential gene expression related to muscle biology and energy metabolism and translation that had largely disappeared by day 14 from the start of the exposure.

systems biology↗

bioRxiv2024

Predicting uptake and elimination kinetics of chemicals in invertebrates: a technicalnote on residual variance modeling

Toxicokinetic models for predicting contents of nanomaterials and other toxic chemicals are often fitted without evaluation of the residual variance structure. The aim of the present study was to evaluate various residual variance structures, assuming either homoscedasticity or heteroscedasticity, when fitting non-linear toxicokinetic one-compartment models for predicting uptake, bioaccumulation and elimination of chemicals in invertebrate organisms. Data describing the exposure of several aquatic and terrestrial invertebrates to specific metal nanomaterials and other chemicals were available from real experiments for evaluating the residual variance functions for toxicokinetic models. As proof of concept, datasets of truly homoscedastic and heteroscedastic nature were simulated. Depending the dataset, applying models with different residuals variance assumption largely affected the residual plots and the error margins of parameters or the predicted content of a chemical. Consequently, selecting the most accurate residual variance functions for toxicokinetic modeling, either homoscedastic or heteroscedastic, improves the prediction of chemical contents in invertebrate organisms and the estimation of the associated uptake and elimination rates. HighlightsO_LIResidual plots indicate if an accurate model was fitted to the toxicological data C_LIO_LIChoice of residual variance function affects the error margins of predicted chemicals C_LIO_LISelecting proper residual variance models may prevent false positives and negatives C_LI

pharmacology and toxicology↗

bioRxiv2024

A simple in vitro fermentation model to detect alterations in gut microbiota-dependent bile acid profiles

A previous in vivo study showed that lincosamide antibiotics (lincomycin and clindamycin) could induce changes in the gut bacterial community, leading to significant changes in fecal bile acid profiles. Herein, our aim is to develop an animal alternative in vitro model for studying gut microbiota-dependent bile acid profiles induced by xenobiotics. The effects of lincosamides were evaluated using this model, and results obtained were verified by comparing with those of the previous in vivo study. Fecal sample processing and bile acid incubation conditions were developed and optimized using feces collected from Wistar rats, and prepared samples were incubated for 24 h with or without lincosamides. Upon treatment of the fecal gut microbiota with lincosamides primary and secondary bile acids showed obviously increased and decreased levels respectively. Moreover, the changes in bile acid profile could be linked to a reduced richness of family Erysipelotrichaceae, Bacteroidacea and Lactobacillaceae or Prevotellaceae. The consistent consequences of in vivo and in vitro provides a proof of principle for further application on elucidating effects of other xenobiotics on the gut bacterial community and related bile acid metabolism, thereby contributing to the 3Rs (replacement, reduction and refinement) in animal testing.

biochemistry↗