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Effect of Route of Exposure on the Toxicity Behavior of Nanomaterials
Published in Vineet Kumar, Nandita Dasgupta, Shivendu Ranjan, Nanotoxicology, 2018
Praveen Guleria, Shiwani Guleria, Vineet Kumar
The intestinal simulation was developed by co-culturing Caco-2 enterocytes, TH29-MTX mucin producing cells, and liver simulation was represented by Hep G2/C3A liver cells. Only 5% of the nanoparticles could move across the intestinal simulations and the remaining 95% were not able to move across the intestinal simulations. Post intestinal transfer, the nanoparticles entered the liver and induced the release of aspartate aminotransferase in liver simulations. Release of this enzyme in the liver indicated liver cell injury (Esch et al. 2014). Likewise, a simulation consisting of Caco-2/TC7: HT29-MTX intestinal co-cultured cells with mucus secretion was developed to evaluate the effect of silver nanoparticles in the gastrointestinal tract of humans during oral uptake. Nanoparticles were observed to enhance reactive oxygen species production thus inducing oxidative stress. Further, increase in the level of interleukin-8 and alteration in the cellular proteome was noticed. Thus, nanoparticles triggered a toxic response in the gastrointestinal simulation cells. However, the mucus secretions were reducing the uptake of nanoparticles by the cellular membranes (Georgantzopoulou et al. 2016) (Figure 5.5).
Alterations in Cellular Enzyme Activity, Antioxidants, Adenylates, and Stress Proteins
Published in Alan G. Heath, Water Pollution and Fish Physiology, 2018
Enzymes from different tissues may be affected very differently by cadmium. An example of this is seen in the study by Hilmy et al. (1985) in which juvenile mullet were exposed to cadmium at a fairly high concentration. Enzyme activities were measured daily for 4 days. In contrast to the inhibition of aspartate aminotransferase in the liver of cunner, which was mentioned above, they observed a strong stimulation of this enzyme in the heart and gill by cadmium, and this increased over the 4-day period. Enzyme from liver exhibited an initial stimulation followed by inhibition, which suggests that a low tissue concentration of cadmium stimulated activity, but as the concentration built up over time, inhibition of enzyme activity occurred. Another transferase, alanine aminotransferase, was also induced by cadmium in the two non-hepatic tissues of the mullet, but inhibited in the liver.
Evaluating the Interactions of Silver Nanoparticles and Mammalian Cells Based on Biomics Technologies
Published in Huiliang Cao, Silver Nanoparticles for Antibacterial Devices, 2017
Since Ag NPs will eventually be used in the human body, animal experiment is still a common method to study the biological properties of Ag NPs. Takenaka et al. (2001) treated rats with 15-nm Ag NPs and found that the particles entered the lungs, blood, liver, kidney, spleen, brain, heart, nasal cavities and lung-associated lymph nodes. Garcia et al. found that a low dose (1 mg/kg) of Ag NPs resulted in no changes in body and testis weights, sperm concentration and motility, fertility indices or follicle-stimulating hormone and luteinising hormone serum concentrations. While serum and intratesticular testosterone concentrations were increased, epithelium morphology, germ cell apoptosis and Leydig cell size were significantly changed (Garcia et al. 2014). Shahare et al. observed the effect of Ag NPs (3–20 nm) on small intestinal mucosa of Swiss albino male mice. The results revealed that Ag NPs significantly decreased the body weight of mice and damage to the epithelial cell microvilli and intestinal glands. The loss of microvilli might reduce the absorptive capacity of the intestinal epithelium and has led to weight loss (Shahare et al. 2013). Al Gurabi et al. (2015) investigated the intraperitoneal toxicity of Ag NPs in Swiss albino mice. Ag NPs induced a significant increase in serum liver injury markers including alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase; they also caused severe damage to the liver.
Histological, oxidative and immune changes in response to 9,10-phenanthrenequione, retene and phenanthrene in Takifugu obscurus liver
Published in Journal of Environmental Science and Health, Part A, 2020
Shulun Jiang, Jian Yang, Di-an Fang
Superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) are frequently used as biomarkers to evaluate oxidative/antioxidant effects of exogenous pollutants on organisms.[17, 18] Following exposure to water-soluble fraction of Arabian crude oil which mainly contained PAHs mixture, SOD activity was significantly lowered while CAT activity was not affected in the European sea bass Dicentrarchus labrax,[19] and MDA content in Lateolabrax japonicus livers was elevated as well.[20] Plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities represent harmful effects on liver. In response to PAHs contamination, these two indices were significantly altered in the carp Cyprinus carpio.[21] Besides, immunoglobulin (Ig) and lysozyme (LZM) are traditional indicators to assess in vivo immune responses to xenobiotics. LZM was the most sensitive marker of the PAHs impacts on the juvenile European flounder.[22] PAHs pollution significantly lowered total Ig (T-Ig) content in the estuarine killifish F. heteroclitus.[23] These indices may be useful to compare toxicity between PAHs and their derivatives to T. obscurus.