Sylwester Smoleń

Objective: This study was designed to evaluate the effect of baked freeze-dried sprats (SPR) added to experimental diets of Wistar rats, with induced streptozotocin (STZ) oxidative stress, on selected biochemical markers involved in antioxidative, immune responses, and thyroid function. Material and Methods: Male Wistar rats (n = 48) were assigned to four experimental groups: C control group, STZ group of rats injected with streptozotocin, SPR group fed diet containing sprats, and STZ + SPR group. Concentrations of selected minerals were determined in urine, feces and selected organs. Serum thyroid hormones (T3, T4), a thyroid-stimulating hormone (TSH) concentration, and the activity of antioxidant enzymes (GPx, GR, SOD) were assessed. The relative expression of Txnrd1, Gpx1/3, Dio1–3 was quantified. Results: The highest concentrations of Mg, I, and Se were observed in the liver of the SPR and STZ + SPR groups compared with the C and STZ groups. T₄ was significantly higher in all experimental groups compared to the C group. mRNA Txnrd1 expression was higher in the thyroid of the SPR and STZ + SPR groups than in the C and STZ groups. The thyroid in STZ + SPR exhibited higher Dio1 with lower Dio2 and Dio3 expression. Conclusions: It can be concluded that baked sprats are the source of bioavailable minerals involved in the reduction of oxidative stress and the modulation of iodine metabolism in rats with oxidative stress caused by impaired glucose metabolism.

In recent decades, there has been increased in interest in the issue of heavy metal pollution in aquatic environments, which is directly linked to industrial development, the intensification of agriculture and ongoing urbanisation. Heavy metals such as mercury (Hg), lead (Pb), cadmium (Cd) and arsenic (As) belong to a group of particularly hazardous pollutants due to their persistence, lack of biodegradability and ability to accumulate in living organisms. Introduced into the aquatic environment from both natural and anthropogenic sources (e.g. industrial effluents, agricultural runoff), they can subsequently be taken up by aquatic organisms and incorporated into food chains. Study conducted in various regions of the world indicates, fish are an effective bioindicator of aquatic environmental pollution, and their analysis allows for the assessment of potential health risks to consumers. The objective of this study was evaluation of the effect of sprats or sardines addition to the experimental diets on accumulation of some heavy metals in selected organs of experimental rats.

One of the effects of years of intensive agricultural production is a reduction in the supply of minerals, including selenium and iodine, in food. This is due to the fact that crop varieties bred as a result of the green revolution have a lower mineral content than traditional varieties grown earlier. The problem of deficient content of the aforementioned elements in soils, and insufficient its transfer to plants and food, consequently, is also of great importance, particularly in areas of endemic deficiency. Currently, several billion people have symptoms of nutrient deficiency or suffer from the related so-called “hidden hunger.” In particular, iodine and selenium deficiency affect 30% and 15% of the population, respectively. Natural supplementation of deficient mineral content in food can take place through biofortification (enrichment) of crops with these nutrients, which falls within the scope of functional food production. This has been proven to be one of the cheapest and relatively effective processes for counteracting or alleviating mineral deficiencies in humans. The herbal plants included in the project (some of which are also spices) can be excellent carriers of iodine and selenium to the human diet. Numerous studies on the effects of selenium alone or iodine alone on plants have been conducted worldwide for several decades. Work on the topic of simultaneous application of both elements is rare. It is therefore justified to conduct research on the biofortification of herbal plants in selenium and iodine with the additional application of SA, especially taking into account their mutual influence on metabolic processes in plants and the possibility of modifying health-promoting properties, which is particularly important in the case of herbal plants. Description of basic research. The research plan includes tasks related to the introduction of iodosalicylates into herbal plants. The use of iodosalicylates in biofortification is justified as they are naturally occurring compounds in plants. To date, iodosalicylates have not been used in research on iodine biofortification of herbal plants. Research proposed in the project will include the application of iodosalicylates separately and together with selenium; potassium iodide and selenium in combination with SA will also be tested along with the positive control of the study, i.e. iodides alone. The research will include the analysis of transformations of iodine compounds in herbal plants, including the synthesis of: iodotyrosine, iodine derivatives of benzoic acid and PDTHAs (plant-derived thyroid hormone). In addition, the research plan will investigate the transformations in herbal plants of selenium (in the form of SeO42-) to seleno organic compounds (SeMet, SeOMet, Se2Cys2, SeMetCys) exhibiting higher health-promoting properties for humans than the SeO42- ions; the effect of additional application of iodine and salicylic acid will also be evaluated. Project Objective. The aim of the research is to determine the possibility of carrying out biofortification (enrichment) of selected herbal plants species in selenium and iodine with the use of inorganic iodine (potassium iodide) and selenium as well as organic forms of iodine (5-iodosalicylic acid and 3,5-diiodosalicylic acid) including the effect of salicylic acid (abbreviated: SA) on the process. The aim of the research is to analyse the changes that may occur under the influence of applied compounds in the chemical composition and health-promoting properties of herbal plants, also after post-harvest processing of plant material. The grant includes research with the following herbal plant species: angelica (Angelica archangelica L.), St. John's wort (Hypericum perforatum L.), California poppy (Eschscholzia californica Cham.), basil (Ocimum basilicum L.), lemon balm (Melissa officinalis L.), oregano (Origanum vulgare L.), dill (Anethum graveolens L.), caraway /meridian fennel/ (Carum carvi L.), sage /Salvia/ (Salvia officinalis L.) and thyme (Thymus vulgaris L.). Herb species from different botanical families, with bioactive substances belonging to different chemical groups and thus exerting a variety of medicinal/health effects on the human body were selected for the study. Herbal plants will be grown in a hydroponic nutrient film technique system (NFT). Iodine and selenium compounds will be applied to nutrient solutions containing all other plant nutrients. The application of iodine and selenium, in addition to causing the biofortification effect, can boost the health-promoting properties of these plants, by increasing the content of bioactive compounds and polyphenols in plants. SA applied for fertilization with inorganic iodine and selenium can stimulate their uptake by plants, while enriching them with SA and products of its metabolism in plants. The completion of the research will make it possible to evaluate the effect of iodine and/or selenium applied without or together with SA on the yield and chemical composition of herbaceous plants, including the content of: macro- and micronutrients, bioactive substances, nutraceuticals, vitamins as well as antioxidant capacity of the herbal plants. It is also planned to investigate the stability of selenium (selenates and resulting seleno amino acids) and iodine (iodides and iodosalicylates and their metabolites, among others: iodotyrosine, 4-iodobenzoic acid, 2,3,5-triiodobenzoic acid, PDTHA) during post-harvest processing of herbs, including the most typical processes, i.e.: blanching and freezing; drying under variable thermal conditions at +30℃ and +60℃ as well as pesto production. These issues have not yet been recognized in scientific research.

Fish are an important part of well-balanced diet. According to current dietary recommendations, they should be consumed twice a week. Sardines, being small-boned fish, are most often consumed whole, but in the form of canned or smoked products. These fish can be consumed after heat treatment, such as baking. In form of baked products, they are a source of high-quality protein, fatty acids, including n-3 fatty acids, and minerals (e.g., calcium, magnesium, iron, copper, and iodine). The aim of this project was to evaluate the effect of baked and freeze-dried sardines added to experimental diets on selected biochemical parameters related to lipid metabolism, oxidative stress, inflammation, and the bioavailability of selected minerals in rats with induced oxidative stress.

The immune system protects the human body against all types of infections and is designed to mitigate factors that influence its development. For this reason, people seeking to protect themselves against infections use various vitamin and mineral supplements and natural food products, especially herbs. Nutritional status plays an important role in the proper functioning of the immune system. It has been documented that protein, n-3 fatty acids, vitamins D and A, magnesium, calcium, iron, zinc, iodine and selenium are essential for the body's immune response. A well-balanced diet containing foods rich in the nutrients mentioned above may be one of the most important factors in preventing and combating SARS-CoV-2 and other infections. Sprats appear to be natural foods that can improve our nutritional status. They are a rich source of n-3 fatty acids, vitamin D, calcium, magnesium, zinc, selenium, and iodine. The aim of the project was to evaluate the effect of addtion of baked sprats in experimental diets and their influence on selected biochemical parameters related to oxidative stress and inflammation rat organism.

To decrease the risk of metabolic syndrome and other lifestyle-related diseases, the U.S. Environmental Protectional Agency (EPA) and Food and Drug Administration (FDA) advises consuming 2 to 3 servings of fish a week, amounting to approximately 240-320 grams. Fish from the Spratus family are highly recommended for the general adult population, as well as for young children and pregnant women, due to their elevated concentrations of unsaturated fatty acids (particularly omega-3) and minimal mercury levels. Omega-3 fatty acids have beneficial properties, such as reducing metabolic disorders and chronic inflammation. EPA and DHA are particularly well known for lowering serum triglyceride levels by reducing the liver’s production of very low-density lipoprotein (VLDL) particles and accelerating the removal of triglycerides from the bloodstream. This is primarily achieved by reducing hepatic lipogenesis through the inhibition of the SREBP-1c transcription factor, which reduces the activity of enzymes responsible for fat synthesis. Omega-3 fatty acids also stimulate β-oxidation (the breakdown of fatty acids) in mitochondria and peroxisomes, leaving fewer raw materials available for the formation of new triglycerides. Finally, they increase the activity of lipoprotein lipase, an enzyme that accelerates the removal of triglycerides from circulating chylomicrons and VLDL particles. Furthermore, EPA and DHA enhance endothelial and vascular function, mitigate the risk of arrhythmia, enhance insulin sensitivity and lower blood pressure, thereby reducing cardiovascular risk. Fish enhances the immune system through a combination of bioactive peptides, omega-3 fatty acids, vitamins, and minerals. The proteins and omega-3 fatty acids (EPA and DHA) exhibit strong anti-inflammatory and antioxidant effects by inhibiting pro-inflammatory cytokines, stimulating cytoprotective enzymes, and regulating the function of T cells and macrophages. In addition, the fat-soluble vitamins D3 and E support the maturation of immune cells, phagocytosis, and the elimination of pathogens, while minerals such as selenium and zinc protect white blood cells from oxidative damage and maintain essential cellular defense mechanisms.

Background/Objectives: Iodine plays a key role in thyroid hormone synthesis and metabolic regulation in vertebrates. This study aimed to evaluate the in vivo bioavailability of iodine and assess selected biochemical parameters and thyroid-related gene expression in male Wistar rats fed lettuce (Lactuca sativa L.) biofortified with iodoquinolines (8-hydroxy-7-iodo-5-quinolinesulfonic acid or 5,7-diiodo-8-quinolinol) or potassium iodate. Methods: Two iodine intake levels were applied, a nutritionally adequate iodine level and a supranutritional level, to evaluate the nutritional safety of iodine obtained from biofortified vegetables. Results: A diet containing lettuce biofortified with iodoquinolines at the adequate level had no significant effect on thyroid hormone concentrations, the expression of Dio1, Dio2, Slc5a5, and Tpo genes, or thyroid morphology. While supranutritional iodine intake led to increased levels of T4, fT4, T3, and fT3, all hormone concentrations remained within the physiological range. No elevation in liver enzyme activity (ALT, AST, ALP) was observed, indicating the absence of hepatotoxic effects from high-iodine diets based on biofortified lettuce. Compared to potassium iodate, iodoquinolines demonstrated superior bioavailability, as evidenced by enhanced iodine accumulation in tissues and more efficient thyroid hormone synthesis. Conclusions: To the best of our knowledge, this is the first in vivo nutritional study assessing the physiological effects of supranutritional iodine intake from a biofortified plant source. These findings confirm the nutritional safety and efficacy of iodine biofortification using iodoquinolines and highlight the need for further research, including human nutritional clinical trials.

Background/Objectives: Iodine plays a key role in thyroid hormone synthesis and metabolic regulation in vertebrates. This study aimed to evaluate the in vivo bioavailability of iodine and assess selected biochemical parameters and thyroid-related gene expression in male Wistar rats fed lettuce (Lactuca sativa L.) biofortified with iodoquinolines (8-hydroxy-7-iodo-5-quinolinesulfonic acid or 5,7-diiodo-8-quinolinol) or potassium iodate. Methods: Two iodine intake levels were applied: a nutritionally adequate iodine level and a supranutritional level, to evaluate the nutritional safety of iodine obtained from biofortified vegetables. Results: A diet containing lettuce biofortified with iodoquinolines at the adequate level had no significant effect on thyroid hormone concentrations, expression of Dio1, Dio2, Slc5a5, and Tpo genes, or thyroid morphology. While supranutritional iodine intake led to increased levels of T4, fT4, T3, and fT3, all hormone concentrations remained within the physiological range. No elevation in liver enzyme activity (ALT, AST, ALP) was observed, indicating the absence of hepatotoxic effects from high-iodine diets based on biofortified lettuce. Compared to potassium iodate, iodoquinolines demonstrated superior bioavailability, as evidenced by enhanced iodine accumulation in tissues and more efficient thyroid hormone synthesis. Conclusions: To the best of our knowledge, this is the first in vivo nutritional study assessing the physiological effects of supranutritional iodine intake from a biofortified plant source. These findings confirm the nutritional safety and efficacy of iodine biofortification using iodoquinolines and highlight the need for further research, including human nutritional clinical trials.