Immunological, oxidoreductive, biochemical indicators, microbial enzymes in biological material taken from rats fed a diet with the addition of various sources of fiber and copper nanoparticles - Jerzy Juśkiewicz; Katarzyna Ognik; Bartosz Fotschki; Magdalena Krauze; Ewelina Cholewińska; Anna Stępniowska; Krzysztof Tutaj; Dorota Napiórkowska; Irena Godycka-Kłos; Łucja Brzuzan (2023)
Dietary copper (Cu) is required for normal functioning of numerous basic biochemical and physiological processes in theorganism. Recently, nanoparticles have emerged as important players in modern science, including nutritional status ofthe host. In the series of the own experiments, we have shown the pros and cons of dietary copper nanoparticles (Cu-NP) on the intestinal, circulatory system, internal organs and brain functioning. For instance, we have shown that incomparison to commonly used dietary CuCO3, Cu nanoparticles (at recommended Cu dietary level) to a greater extentwere absorbed from the intestine, accumulated in brain tissue, exerted antimicrobial effect in the caecum, enhancedlipid oxidation processes and caused morphological damages in the liver and lungs of rats. On the other hand, replacingCuCO3 with copper nanoparticles advantageously protects proteins and DNA against oxidation and nitration processesin laboratory rats. Due to wide physiological effect of the Cu-NP in the whole organism it might be important to regulateits area of reactivity. The intestinal environments themselves, both as the upper and lower gut, modulate metabolicbody response through e.g. activation of intestinal immunological cells and stimulation or thwarting of the “forgottenorgan” – large intestinal microbiota. One of the paramount dietary components is fibre, and its type would play a crucialrole in the assimilation and then physiological activity of Cu-NP. Therefore the main aim of this project is to verify thestatement that the physical, chemical and biological properties of dietary fibre largely affect the intestinal and internalorgans activity of Cu-NP, thus modulate the health status of the body. We hypothesized that a dietary combination ofcopper nanoparticles with either a control inert (cellulose) or a prebiotic (inulin) or a viscous (high viscosity pectin) or abulking (psyllium) fibre would affect physiological responses in the gastrointestinal tract and thus regulate effect of thisform of dietary Cu in the organism.The rat Wistar (Cmdb:Wi CMDB) will be used as a research model, i.e. an established host model for nutritional andmetabolic studies, including the gastrointestinal and hepatic responses to nutritional interventions. The following partialstatements will be verified:- different physicochemical properties of dietary fibre shape metabolic responses in the host consumed different dosesof Cu-NP;- different fibfibre types exert alleviating effects in the host subjected to higher than recommended Cu (as Cu-NP) dietaryaddition;- the changes in the small intestine exerted by different dietary fibre would modulate Cu-NP effects on small intestinalmorphology, permeability/integrity, epigenetic changes as well as immunological and redox status;- the differentiation in large intestinal bacterial population and its activity under dietary fibre manipulations play animportant role in subsequent activity of copper nanoparticles in the body, e.g. in the liver, femur, aorta;- under undesired dietary condition, e.g. high dosage of copper nanoparticles, the caecal microbiota would showdifferent adaptation mechanisms.The animals will be fed standard semi-purified diet with dietary addition of two copper nanoparticles dosages (Curecommended and two times higher) and combined with different types of dietary fibre (control, with prebiotic effect,with bulk effect, with viscous effect). During the experimental feeding (on living animals), the attention will be paid tofaecal and urinal excretion patterns of Cu, as well as faecal microbial enzymatic and metabolic activity. At thetermination of the study, the samples of intestinal digesta (upper and lower intestines) and tissues (blood, intestines,liver, femur, aorta) will be thoroughly examined with regard to microbial, morphological, immunological and redoxstatus, as well as epigenetic changes.The main intention of the project’s authors is to bring as much as possible new insight with regard to the question whichproperties of dietary fibre would support the “good face” and alleviate the “bad face” of ingested copper nanoparticlesin the organism.
Keywords: copper nanoparticles; diet; dietary fibre; intestine; liver; rat