Ex Vivo Human Colon Tissue Exposure to Pristine Graphene Activates Genes Involved in the Binding, Adhesion and Proliferation of Epithelial Cells.

Toxicology studies on pristine graphene are limited and lack significant correlations with actual human response. The goal of the current study was to determine the response of total colonic human tissue to pristine graphene exposure. Biopsy punches of colon tissues from healthy human were used to assess the biological response after ex vivo exposure to graphene at three different concentrations (1, 10, and 100 µg/mL).

Differential Toxicological Outcome of Corn Oil Exposure in Rats and Mice as Assessed by Microbial Composition, Epithelial Permeability, and Ileal Mucosa-Associated Immune Status.

Studies to evaluate the toxicity of xenobiotics on the human gut microbiome and related health effects require a diligent selection of (1) an appropriate animal model to facilitate toxicity assessment in predicting human exposure, and (2) an appropriate non-interfering vehicle for the administration of water insoluble compounds. In biomedical studies with water insoluble xenobiotics, corn oil is one of the most commonly used nonaqueous vehicles. This study evaluated the suitability of corn oil as a vehicle in adult female Sprague Dawley rats and adult CD-1 mice; the rodent models that are often utilized in toxicological studies.

Impact of Pristine Graphene on Intestinal Microbiota Assessed Using a Bioreactor-Rotary Cell Culture System.

The increased use of graphene in consumer products such as food contact materials requires a thorough understanding of its effects on the gastrointestinal commensal bacterial population. During the first phase of study, three representative commensal bacterial species (, , and ) were exposed to different concentrations (1, 10, and 100 μg/mL) of pristine graphene for 3, 6, and 24 h in the Bioreactor Rotary Cell Culture System (BRCCS) which allowed a continuous interaction of intestinal microbiota with the pristine graphene without precipitation of test material. The results showed that pristine graphene had dose-dependent effects on the growth of selective bacteria.

The impact of tomato fruits containing multi-walled carbon nanotube residues on human intestinal epithelial cell barrier function and intestinal microbiome composition.

Carbon nanomaterials (CNMs) can positively regulate seed germination and enhance plant growth. However, clarification of the impact of plant organs containing absorbed CNMs on animal and human health is a critical step of risk assessment for new nano-agro-technology. In this study, we have taken a comprehensive approach to studying the effect tomato fruits derived from plants exposed to multi-walled carbon nanotubes (CNTs) have on gastrointestinal epithelial barrier integrity and their impact on the human commensal intestinal microbiota using an in vitro cell culture and batch human fecal suspension models.

Effects of carbon-based nanomaterials on seed germination, biomass accumulation and salt stress response of bioenergy crops.

Bioenergy crops are an attractive option for use in energy production. A good plant candidate for bioenergy applications should produce a high amount of biomass and resist harsh environmental conditions. Carbon-based nanomaterials (CBNs) have been described as promising seed germination and plant growth regulators.

Multiwalled Carbon Nanotubes Dramatically Affect the Fruit Metabolome of Exposed Tomato Plants.

Here, we reported that multiwalled carbon nanotubes (MWCNT) added to hydroponics system can enhance fruit production of exposed tomato plants. We quantified the exact amount of MWCNT accumulated inside of fruits collected by MWCNT-exposed plants using an advanced microwave induced heating technique (MIH). We found that absorption of MWCNT by tomato fruits significantly affected total fruit metabolome as was confirmed by LC-MS.

Assessment of Effects of the Long-Term Exposure of Agricultural Crops to Carbon Nanotubes.

Carbon-based nanoparticles (CBNs) are nanomaterials that have been shown to be plant growth regulators. Here, we investigated the effects of long-term exposure to multi-walled carbon nanotubes (MWCNTs) on the growth of three important crops (barley, soybean, and corn). The tested species were cultivated in hydroponics supplemented with 50 μg/mL MWCNTs.

Graphene and carbon nanotubes activate different cell surface receptors on macrophages before and after deactivation of endotoxins.

Nanomaterial synthesis and handling in a non-sterile environment can result in the final product becoming contaminated with bacterial endotoxin or lipopolysaccharides (LPB). During toxicological testing, the effects caused by endotoxin-contaminated nanomaterials can be misinterpreted in the end-point analysis (such as cytotoxicity and immune responses) and could result in erroneous conclusions. The objective of this study was twofold: (i) to test different carbon-based nanomaterials (CBNs) [pristine graphene and multi-wall carbon nanotubes (MWCNTs)] for the presence of endotoxin and develop strategies for depyrogenation, and (ii) to compare the immune response exhibited by macrophages after exposure to native CBNs versus depyrogenated CBNs.

Polyphenolic extract of InsP 5-ptase expressing tomato plants reduce the proliferation of MCF-7 breast cancer cells.

In recent years, by extensive achievements in understanding the mechanisms and the pathways affected by cancer, the focus of cancer research is shifting from developing new chemotherapy methods to using natural compounds with therapeutic properties to reduce the adverse effects of synthetic drugs on human health. We used fruit extracts from previously generated human type I InsP 5-ptase gene expressing transgenic tomato plants for assessment of the anti-cancer activity of established genetically modified tomato lines. Cellular assays (MTT, Fluorescent microscopy, Flow Cytometry analysis) were used to confirm that InsP 5-ptase fruit extract was more effective for reducing the proliferation of breast cancer cells compared to wild-type tomato fruit extract.

Carbon nanotubes as carriers of Panax ginseng metabolites and enhancers of ginsenosides Rb1 and Rg1 anti-cancer activity.

A major benefit to nanomaterial based-medicine is the ability to provide nanosized vehicles for sporadic metabolites. Here, we describe how the conjugation of valuable ginseng secondary metabolites (ginsenoside Rb1 or Rg1) with carbon nanotubes (CNT) can enhance their anti-proliferative and anti-cancer effects. Ginsenoside-CNT conjugate (Rb-CNT or Rg-CNT) permitted the ginsenosides to be used at a low dose, yet achieve a higher incidence of cancer killing.

Comparative study of plant responses to carbon-based nanomaterials with different morphologies.

The relationship between the morphology of carbon-based nanomaterials (CBNs) and the specific response of plants exposed to CBNs has not been studied systematically. Here, we prove that CBNs with different morphologies can activate cell growth, germination, and plant growth. A tobacco cell culture growth was found to increase by 22%-46% when CBNs such as helical multi-wall carbon nanotubes (MWCNTs), few-layered graphene, long MWCNTs, and short MWCNTs were added to the growth medium at a concentration of 50 μg ml(-1).

Genetic reduction of inositol triphosphate (InsP₃) increases tolerance of tomato plants to oxidative stress.

We demonstrate here that the reduction of InsP 3 , the key component of the phosphoinositol pathway, results in changes in ROS-scavenging machinery and, subsequently, increases the tolerance of tomato plants to light stress. Different plant stress signaling pathways share similar elements and, therefore, 'cross-talk' between the various pathways can exist. Links between the phosphoinositol signaling pathway and light signaling were recently found.

Impact of carbon nanotube exposure to seeds of valuable crops.

Multiwalled carbon nanotubes (MWCNTs) affected seed germination, growth, and the development of three important crops (barley, soybean, corn). Early seed germination and activation of growth in exposed seedlings was observed when MWCNTs were added to sterile agar medium. Similarly, seed germination was activated for all tested crop species when MWCNTs were deposited on seed surfaces.