Toxic effects of repeated oral exposure of silver nanoparticles on small intestine mucosa of mice

2013 ◽  
Vol 23 (3) ◽  
pp. 161-167 ◽  
Author(s):  
Brigesh Shahare ◽  
Madhu Yashpal
Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6610
Author(s):  
Ana T. Rufino ◽  
Ana Ramalho ◽  
Adelaide Sousa ◽  
José Miguel P. Ferreira de Oliveira ◽  
Paulo Freitas ◽  
...  

Silver nanoparticles (AgNP) have been increasingly incorporated into food-related and hygiene products for their unique antimicrobial and preservative properties. The consequent oral exposure may then result in unpredicted harmful effects in the gastrointestinal tract (GIT), which should be considered in the risk assessment and risk management of these materials. In the present study, the toxic effects of polyethyleneimine (PEI)-coated AgNP (4 and 19 nm) were evaluated in GIT-relevant cells (Caco-2 cell line as a model of human intestinal cells, and neutrophils as a model of the intestinal inflammatory response). This study also evaluated the putative protective action of dietary flavonoids against such harmful effects. The obtained results showed that AgNP of 4 and 19 nm effectively induced Caco-2 cell death by apoptosis with concomitant production of nitric oxide, irrespective of the size. It was also observed that AgNP induced human neutrophil oxidative burst. Interestingly, some flavonoids, namely quercetin and quercetagetin, prevented the deleterious effects of AgNP in both cell types. Overall, the data of the present study provide a first insight into the promising protective role of flavonoids against the potentially toxic effects of AgNP at the intestinal level.


2021 ◽  
Vol 22 (5) ◽  
pp. 2536
Author(s):  
Rong-Jane Chen ◽  
Chiao-Ching Huang ◽  
Rosita Pranata ◽  
Yu-Hsuan Lee ◽  
Yu-Ying Chen ◽  
...  

Silver nanoparticles pose a potential risk to ecosystems and living organisms due to their widespread use in various fields and subsequent gradual release into the environment. Only a few studies have investigated the effects of silver nanoparticles (AgNPs) toxicity on immunological functions. Furthermore, these toxic effects have not been fully explored. Recent studies have indicated that zebrafish are considered a good alternative model for testing toxicity and for evaluating immunological toxicity. Therefore, the purpose of this study was to investigate the toxicity effects of AgNPs on innate immunity using a zebrafish model and to investigate whether the natural compound pterostilbene (PTE) could provide protection against AgNPs-induced immunotoxicity. Wild type and neutrophil- and macrophage-transgenic zebrafish lines were used in the experiments. The results indicated that the exposure to AgNPs induced toxic effects including death, malformation and the innate immune toxicity of zebrafish. In addition, AgNPs affect the number and function of neutrophils and macrophages. The expression of immune-related cytokines and chemokines was also affected. Notably, the addition of PTE could activate immune cells and promote their accumulation in injured areas in zebrafish, thereby reducing the damage caused by AgNPs. In conclusion, AgNPs may induce innate immune toxicity and PTE could ameliorate this toxicity.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hamed Nosrati ◽  
Manijeh Hamzepoor ◽  
Maryam Sohrabi ◽  
Massoud Saidijam ◽  
Mohammad Javad Assari ◽  
...  

Abstract Background Silver nanoparticles (AgNPs) can accumulate in various organs after oral exposure. The main objective of the current study is to evaluate the renal toxicity induced by AgNPs after repeated oral exposure and to determine the relevant molecular mechanisms. Methods In this study, 40 male Wistar rats were treated with solutions containing 30, 125, 300, and 700 mg/kg of AgNPs. After 28 days of exposure, histopathological changes were assessed using hematoxylin-eosin (H&E), Masson’s trichrome, and periodic acid-Schiff (PAS) staining. Apoptosis was quantified by TUNEL and immunohistochemistry of caspase-3, and the level of expression of the mRNAs of growth factors was determined using RT-PCR. Results Histopathologic examination revealed degenerative changes in the glomeruli, loss of tubular architecture, loss of brush border, and interrupted tubular basal laminae. These changes were more noticeable in groups treated with 30 and 125 mg/kg. The collagen intensity increased in the group treated with 30 mg/kg in both the cortex and the medulla. Apoptosis was much more evident in middle-dose groups (i.e., 125 and 300 mg/kg). The results of RT-PCR indicated that Bcl-2 and Bax mRNAs upregulated in the treated groups (p < 0.05). Moreover, the data related to EGF, TNF-α, and TGF-β1 revealed that AgNPs induced significant changes in gene expression in the groups treated with 30 and 700 mg/kg compared to the control group. Conclusion Our observations showed that AgNPs played a critical role in in vivo renal toxicity.


1985 ◽  
Vol 104 (2) ◽  
pp. 435-443 ◽  
Author(s):  
A. N. Janes ◽  
T. E. C. Weekes ◽  
D. G. Armstrong

SummaryTwo groups of six sheep were fed either dried-grass or ground maize-based diets for at least 4 weeks before slaughter. Samples of the small intestinal mucosa and spancreatic tissue were assayed for a-amylase, glucoamylase, maltase and oligo-l,6-glucosidase.The pancreatic tissue contained high activities of α-amylase and much lower activities of glucoamylase, maltase and oligo-1,6-glucosidase. There was no effect of diet on the specific activities of any of these enzymes in the pancreatic tissue.The activity of α-amylase adsorbed on to the mucosa of the small intestine was greatest in the proximal region of the small intestine, the activity generally declining with increasing distance away from the pylorus. There was no diet effect on the absorbed α-amylase activity.Similar patterns of distribution along the small intestine were observed for maltase, glucoamylase and oligo-1,6-glucosidase with the highest activities in t he jejunum. There was no overall effect of diet on glucoamylase or maltase specific activities and glucoamylase total activity, although the total activities of maltase and oligo-1,6-glucosidase were significantly greater for the sheep fed the ground maize-based diet (P < 0·05).It is suggested that ruminant animals may be capable of digesting large amounts of starch in the small intestine through an adaptation in the activity of the host carbohydrases.


2016 ◽  
Vol 32 (2) ◽  
pp. 609-618 ◽  
Author(s):  
Guangqiu Qin ◽  
Song Tang ◽  
Shibin Li ◽  
Haoliang Lu ◽  
Yanwu Wang ◽  
...  

2021 ◽  
Vol 09 ◽  
Author(s):  
Mark Sergeevich Stepankov ◽  
Marina Aleksandrovna Zemlyanova ◽  
Nina Vladimirovna Zaitseva ◽  
Anna Mikhailovna Ignatova ◽  
Alena Evgenievna Nikolaeva

Background: Currently, the range of copper (II) oxide nanoparticles’ (CuO NPs) applications is expanding and the global production of CuO NPs is increasing. In this regard, the risk of exposure of the population to this nanomaterial increases. Objective: The aim of the study is to investigate the patterns of bioaccumulation and toxic effects of CuO NPs after multiple oral exposures. Methods: The particle size was determined by scanning electron microscopy and dynamic laser light scattering. Specific surface area was measured by the method of Brunauer, Emmett, Teller. Total pore volume - by the method of Barrett, Joyner, Khalenda. Twenty-four hours after the final exposure, blood samples were taken for biochemical and hematological analysis, and internal organs were taken to determine their mass, copper concentration and histological analysis. The study was carried out in comparison with copper (II) oxide microparticles (CuO MPs). Results: In terms of size, surface area, and pore volume, the studied copper (II) oxide sample is a nanomaterial. The median lethal dose of CuO NPs was 13187.5 mg/kg of body weight. Bioaccumulation occurs in the stomach, blood, intestines, liver, lungs, kidneys and brain. Pathomorphological changes in the liver are manifested in the form of necrosis, degeneration, hepatitis; kidney - proliferation of mesangial cells, dystrophy; stomach - gastritis; small intestine - hyperplasia, enteritis; large intestine - colitis; lungs - hyperplasia, abscess, pneumonia, bronchitis, vasculitis. Clumps of brown pigment were detected in the kidneys, stomach and lungs. The mass of the stomach and intestines increased, the mass of the liver, kidneys and lungs decreased. Pathomorphological changes in organs are likely to cause an increase in the levels of activity of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, amylase, malondialdehyde concentration and a decrease in plasma antioxidant activity. The proportion of segmented neutrophils, the number of leukocytes are raised, the proportion of lymphocytes is reduced. Conclusion: The degree of bioaccumulation and toxicity of CuO NPs are more expressed in relation to CuO MPs.


2020 ◽  
Vol 36 (6) ◽  
pp. 446-453
Author(s):  
Salma Awad Taghyan ◽  
Hend El Messiry ◽  
Medhat Ahmed El Zainy

This study aimed to evaluate the toxic effect of silver nanoparticles (AgNPs) on the parotid glands (PGs) of albino rats histologically and ultrastructurally and assess the possible protective effect of ascorbic acid as an antioxidant. Thirty male albino rats weighing between 150 mg and 200 mg were divided into three groups: the control group (C1) contained 10 rats that received 2 mg/kg (body weight (bw)) of aqueous nitrate buffer by intraperitoneal (IP) injection daily for 28 days; the AgNPs group contained 10 rats that received 2 mg/kg (bw) IP AgNPs daily for 28 days; and the AgNPs-vitamin C group contained 10 albino rats that received 2 mg/kg (bw) AgNPs IP daily for 28 days with oral administration of 100 mg/kg (bw) vitamin C in drinking water daily for 28 days. The PG acinar and ductal cells of the AgNPs group showed signs of toxicity and degeneration characterized as pleomorphic nuclei, binucleation, cytoplasmic vacuolations, and stagnated secretion in the ductal lumen. In addition to degenerated mitochondria, dilated rough endoplasmic reticulum and lysosomes were filled with AgNPs ( p < 0.001). The AgNPs-vitamin C group showed significantly less degenerative changes histologically and ultrastructurally compared to the AgNPs group ( p = 0.002). AgNPs produced significant toxic effects on the PG of albino rats, presumably through the generation of reactive oxygen species and toxic ion release, and administration of vitamin C was shown effective in decreasing these toxic effects.


2017 ◽  
Vol 51 (21) ◽  
pp. 12868-12878 ◽  
Author(s):  
Jing Hou ◽  
Yue Zhou ◽  
Chunjie Wang ◽  
Shiguo Li ◽  
Xiangke Wang

Sign in / Sign up

Export Citation Format

Share Document