Changes of physico-chemical properties of nano-biomaterials by digestion fluids affect the physiological properties of epithelial intestinal cells and barrier models

Abstract

Background The widespread use of nano-biomaterials (NBMs) has increased the chance of human exposure. Although ingestion is one of the major routes of exposure to NBMs, it is not thoroughly studied to date. NBMs are expected to be dramatically modified following the transit into the oral-gastric-intestinal (OGI) tract. How these transformations affect their interaction with intestinal cells is still poorly understood. NBMs of different chemical nature—lipid-surfactant nanoparticles (LSNPs), carbon nanoparticles (CNPs), surface modified Fe3O4 nanoparticles (FNPs) and hydroxyapatite nanoparticles (HNPs)—were treated in a simulated human digestive system (SHDS) and then characterised. The biological effects of SHDS-treated and untreated NBMs were evaluated on primary (HCoEpiC) and immortalised (Caco-2, HCT116) epithelial intestinal cells and on an intestinal barrier model. Results The application of the in vitro SDHS modified the biocompatibility of NBMs on gastrointestinal cells. The differences between SHDS-treated and untreated NBMs could be attributed to the irreversible modification of the NBMs in the SHDS. Aggregation was detected for all NBMs regardless of their chemical nature, while pH- or enzyme-mediated partial degradation was detected for hydroxyapatite or polymer-coated iron oxide nanoparticles and lipid nanoparticles, respectively. The formation of a bio-corona, which contains proteases, was also demonstrated on all the analysed NBMs. In viability assays, undifferentiated primary cells were more sensitive than immortalised cells to digested NBMs, but neither pristine nor treated NBMs affected the intestinal barrier viability and permeability. SHDS-treated NBMs up-regulated the tight junction genes (claudin 3 and 5, occludin, zonula occludens 1) in intestinal barrier, with different patterns between each NBM, and increase the expression of both pro- and anti-inflammatory cytokines (IL-1β, TNF-α, IL-22, IL-10). Notably, none of these NBMs showed any significant genotoxic effect. Conclusions Overall, the results add a piece of evidence on the importance of applying validated in vitro SHDS models for the assessment of NBM intestinal toxicity/biocompatibility. We propose the association of chemical and microscopic characterization, SHDS and in vitro tests on both immortalised and primary cells as a robust screening pipeline useful to monitor the changes in the physico-chemical properties of ingested NBMs and their effects on intestinal cells.

Data-Driven Quantitative Intrinsic Hazard Criteria for Nanoproduct Development in a Safe-by-Design Paradigm: A Case Study of Silver Nanoforms

“…Inhalation is a major route of human exposure to airborne NFs, and it may occur at workplaces, and A549 cells are a well-established line used for inhalation toxicological testing, including AgNFs . Ingestion is another important route of exposure, and with regard to intestinal exposure, ingested NFs pass through various environments before reaching the intestinal cells, such as saliva, gastric, and intestinal fluids. , Due to the complex nature of these fluids such as acidic conditions, the presence of salts and biomolecules, the pchem properties of NFs could be altered before, during, and after passing the gastrointestinal tract, affecting their bioactivity. , To mimic the fate of NFs, simulated digestive fluids were prepared based on ref , and NF preparation in simulated digestion cascade was performed according to ref . Finally, digested and non-digested NFs were exposed to HCT-116 cells, a well-accepted model for testing NF intestinal cytotoxicity …”

“…49 Ingestion is another important route of exposure, 50 and with regard to intestinal exposure, ingested NFs pass through various environments before reaching the intestinal cells, such as saliva, gastric, and intestinal fluids. 51,52 Due to the complex nature of these fluids such as acidic conditions, the presence of salts and biomolecules, the pchem properties of NFs could be altered before, during, and after passing the gastrointestinal tract, affecting their bioactivity. 53,54 To mimic the fate of NFs, simulated digestive fluids were prepared based on ref 55, and NF preparation in simulated digestion cascade was performed according to ref 56.…”

Photoresponsive Inorganic Nanomaterials in Oncology

“…Concerning the oral route, we previously reported that NPs acquire during the transit in the gastrointestinal tract a protein corona that contains proteases potentially able to modulate the NP crossing and effect on the gastrointestinal barrier since involved in the regulation of the intestinal permeability. 165 To impede the formation of the protein corona and to stabilize the NPs avoiding dissolution, biodegradation or agglomeration, surface modifications are normally applied. PEGylation is the most popular one.…”

Iron Oxide (Magnetite)-Based Nanobiomaterial with Medical Applications—Environmental Hazard Assessment Using Terrestrial Model Species

“…Studies on NBMs’ toxicity, including Fe 3 O 4 PEG-PLGA, are mostly available for in vitro models, without much information on their effects on environmental species. Several in vitro cytotoxicity studies with Fe 3 O 4 PEG-PLGA indicate an overall low-to-no toxicity to different cell models [ 16 , 17 , 18 ]. Genotoxicity was also not observed in HCT116 cells exposed to Fe 3 O 4 PEG-PLGA up to 50 μg/mL [ 16 , 18 ], despite the increase in reactive oxygen species (ROS) levels observed above 10 μg/mL [ 16 ].…”

“…Several in vitro cytotoxicity studies with Fe 3 O 4 PEG-PLGA indicate an overall low-to-no toxicity to different cell models [ 16 , 17 , 18 ]. Genotoxicity was also not observed in HCT116 cells exposed to Fe 3 O 4 PEG-PLGA up to 50 μg/mL [ 16 , 18 ], despite the increase in reactive oxygen species (ROS) levels observed above 10 μg/mL [ 16 ]. In a study performed in an environmental species, i.e., using the fish cell lines RTL-W1 (CRL-2301, derived from the liver), RTgill-W1 (CRL-2523, derived from the branchial arc), and RTS-11 (derived from the spleen), up to 100 μg/mL within 24 h [ 19 ] of Fe 3 O 4 PEG-PLGA was also not acutely toxic.…”