The Effect of Copper Nanoparticles and a Different Source of Dietary Fibre in the Diet on the Integrity of the Small Intestine in the Rat.

The aim of the study was to verify the hypothesis regarding the effect of recommended (6.5 mg/kg) or enhanced (13 mg/kg) level of CuNPs in the diet in combination with different types of dietary fibre-cellulose (control), inulin, pectin or psyllium-on selected biological parameters of intestinal integrity in rats. Rats were randomly divided into 10 groups. The first two groups were fed a control diet that contained cellulose, and a mineral mixture with standard or enhanced content of CuCO3. Experimental groups were fed a diet supplemented with CuNPs (6.5 or 13 mg/kg) and combined with different types of fibre (cellulose, pectin, inulin or psyllium). After the feeding period, blood and small intestine samples were collected for further analysis. Replacing CuCO3 by CuNPs in the diet positively reduced the level of lactic acid and apoptosis markers in the small intestine; however, it also resulted in the intensification of DNA oxidation. The most beneficial effect on DNA repair mechanisms is related to inulin, while pectin has the greatest ability to inhibit inflammatory processes that induce the apoptotic death of cells in the small intestine. Our results suggest that dietary fibre supplementation protects the small intestine against potentially harmful, oxidative effects of CuNPs by intensifying the intestinal barrier.

The effect of the high-fat diet supplemented with various forms of chromium on rats body composition, liver metabolism and organ histology Cr in liver metabolism and histology of selected organs.

BACKGROUND: In the present study, we hypothesized that feeding rats a high-fat diet negatively affects liver metabolism and function and disturbs the histology of some internal organs. We also postulated that there is a form of chromium whose administration alleviates the negative effects of a high-fat diet in rats. METHODS: To verify the hypotheses, we tested the effect of various forms of chrome (picolinate - Cr-Pic, Chromium(III)-methionine complex - Cr-Met, and chrome nanoparticles - Cr-NPs) applied in the recommended amount of 0.3 mg/kg of BW on growth parameters, body fat, liver metabolism and functional disorders, and histological parameters of selected internal organs in rats fed a standard (S) or high-fat diet (F). The experiment was conducted on 56 male outbred Wistar rats (Rattus norvegicus. Cmdb:WI) randomly divided into eight experimental groups. For eight weeks the rats received a standard or high-fat diet, without Cr or with Cr at 0.3 mg/kg diet in the form of Cr-Pic, Cr-Met or Cr-NPs. RESULTS AND CONCLUSION: The use of a F diet disrupted the lipid-carbohydrate profile, worsened liver metabolism and function, reduced the expression of hepatic PPAR-α and leaded to negative changes in the histological image of internal organs - liver, kidneys and pancreas. The 8-week use of an chromium supplement in a F diet, regardless of the form used, did not improve the ratio of fat tissue to lean tissue, worsened liver function and negatively affected on the histological image of the liver, kidneys and pancreas. However, the most negative changes in lipid-carbohydrate metabolism and liver functioning were observed with CrNPs supplementation.

Assessment of DNA Methylation and Oxidative Changes in the Heart and Brain of Rats Receiving a High-Fat Diet Supplemented with Various Forms of Chromium.

The aim of the study was to determine how feeding rats a high-fat diet supplemented with various forms of chromium affects DNA methylation and oxidation reactions as well as the histology of heart and brain tissue. The rats received standard diet or high-fat diet and chromium at 0.3 mg/kg body weight (BW) in form of chromium (III) picolinate, chromium (III)-methionine, or nano-sized chromium. The content of malondialdehyde (MDA), protein carbonyl (PC), and 8-hydroxydeoxyguanosine (8-OHDG), the level of global DNA methylation and the activity of selected DNA repair enzymes were determined in the blood. In the brain and heart, the content of MDA, PC, 8-OHDG, and levels of global DNA methylation were determined. The brain was subjected to histological examination. The use of a high-fat diet was found to intensify epigenetic changes and oxidation reactions in the heart and brain. It was concluded that epigenetic changes and oxidation of lipids, proteins, and DNA in the heart and brain of rats resulting from the use of a high-fat diet cannot be limited by supplementing the diet with chromium. It was established that the use of chromium to supplement a high-fat diet intensifies the negative epigenetic and oxidative changes in the heart and brain, especially in the case of chromium nanoparticles.