Histochemical study of intestinal mucins after administration of silver nanoparticles in Sprague–Dawley rats

Abstract

To investigate the effects of silver nanoparticles on the histological structure and properties of the mucosubstances in the intestinal mucosa, Sprague-Dawley rats were divided into four groups (10 rats in each group): vehicle control, low-dose group (30 mg/kg), middle-dose group (300 mg/kg), and high-dose group (1,000 mg/kg), and administered silver nanoparticles (60 nm) for 28 days, following OECD test guideline 407 and using GLP. The control sections contained no silver nanoparticles; however, the treated samples showed luminal and surface particles and the tissue also contained silver nanoparticles. A dose-dependent increased accumulation of silver nanoparticles was observed in the lamina propria in both the small and large intestine, and also in the tip of the upper villi in the ileum and protruding surface of the fold in the colon. The silver nanoparticle-treated rats exhibited higher numbers of goblet cells that had released their mucus granules than the controls, resulting in more mucus materials in the crypt lumen and ileal lumen. Moreover, cell shedding at the tip of the villi was frequent. Lower amounts of neutral and acidic mucins were found in the goblet cells in the silver nanoparticle-treated rats, plus the amount of sialomucins was increased, while the amount of sulfomucins was decreased. In particular, in the colon of the silver nanoparticle-treated rats, sialyated mucins were detected in the lamina propria, the connective tissue under the epithelia. Therefore, the present results suggest that silver nanoparticles induce the discharge of mucus granules and an abnormal mucus composition in the goblet cells in the intestines.

Perturbation of physiological systems by nanoparticles

“…230 Silver nanoparticles increased the amount of sialylated mucins in the gastric mucus, similar to cases of active ulcerative colitis and small intestine carcinoma. 229 Establishing the relevance of these findings to the pathophysiology of the gastrointestinal tract requires further investigation. A lack of adverse effects after oral administration of nanoparticles has also been reported.…”

Bigger Size Silver Nanoparticles Hamper Mother and Fetus Nutrition after Serial Ingestion of Bolotic Colloidal Nano Silver Stirring Solution through Oral Route: A Revolutionary Research Discovery in Teratogenicity & Toxicity Field

“…loss of microvilli, and disruption of other structure which may give passage to bigger size AgNps for entering and abnormally subjected to accumulation into the intestinal wall and then hence into the portal circulation and systemic circulation which results in hamper of nutritional flow. After more than 20 days of serial oral route administration of bigger size AgNps colloidal cool and stirring solution, a dose-dependent increased accumulation and deposition of bigger size AgNps was also observed in the lamina propria in both the small and large intestine of primate vertebrate; lower group of animal of category Sprague-Dawley rats which is found suppressing nutritional activity with frequent cell shedding or weak and sink cell at the tip of the villi in upper GI organs with distal 2/3rd of duodenum, jejunum and ileum (small intestine) [25].…”

“…Bigger size AgNps gained entrance into the human body mostly through oral entry portal route and in powdered form it spreads easily in air, soil and water. It can easily uptake by cell in colloidal form and obstructs tissue nutrition after chronic deposition in tissue space [18][19][20]. There are lot of causes to be dead assure that exposure of bigger size AgNps to GI tract must be taking place in conscious state or unconscious state leads to permanent hamper of nutrition.…”

Nanosilver – Harmful effects of biological activity

“…W kolejnym badaniu szczury eksponowano drogą pokarmową na nanocząstki srebra (60 nm) przez 28 dni (OECD TG 407) (26). Obecność nanocząstek srebra wykryto w jelitach narażanych zwierząt, zaobserwowano także zmiany w strukturze histologicznej i właściwościach śluzówki jelit.…”