Steviol glycosides from Stevia rebaudiana Bertoni mitigate lipid metabolism abnormalities in diabetes by modulating selected gene expression - An in vivo study.

In diabetes, in parallel to hyperglycaemia, elevated serum lipids are also diagnosed, representing a high-risk factor for coronary heart disease and cardiovascular complications. The objective of this study was to unravel the mechanisms that underlie the potential of steviol glycosides (stevioside or rebaudioside A) administered at two doses (500 or 2500 mg/kg body weight for 5 weeks) to regulate lipid metabolism. In this paper, the expression of selected genes responsible for glucose and lipid metabolism (Glut4, Pparγ, Cebpa, Fasn, Lpl and Egr1) in the peripheral tissues (adipose, liver and muscle tissue) was determined using quantitative real-time PCR method. It was found that the supplementation of steviol glycosides affected the expression of Glut4, Cebpa and Fasn genes, depending on the type of the glycoside and its dose, as well as the type of tissue, whish in part may explain the lipid-regulatory potential of steviol glycosides in hyperglycaemic conditions. Nevertheless, more in-depth studies, including human trials, are needed to confirm these effects, before steviol glycosides can be used in the therapy of type 2 diabetes.

Steviol Glycoside, L-Arginine, and Chromium(III) Supplementation Attenuates Abnormalities in Glucose Metabolism in Streptozotocin-Induced Mildly Diabetic Rats Fed a High-Fat Diet.

Stevia rebaudiana Bertoni and its glycosides are believed to exhibit several health-promoting properties. Recently, the mechanisms of the anti-diabetic effects of steviol glycosides (SG) have been the subject of intense research. The following study aims to evaluate the results of SG (stevioside (ST) and rebaudioside A (RA)) combined with L-arginine (L-Arg) and chromium(III) (CrIII) supplementation in streptozotocin- (STZ) induced mild type 2 diabetic rats fed a high-fat diet (HFD), with particular emphasis on carbohydrate and lipid metabolisms. The experiment was carried out on 110 male Wistar rats, 100 of which were fed an HFD to induce insulin resistance, followed by an intraperitoneal injection of streptozotocin to induce mild type 2 diabetes. After confirmation of hyperglycemia, the rats were divided into groups. Three groups served as controls: diabetic untreated, diabetic treated with metformin (300 mg/kg BW), and healthy group. Eight groups were fed an HFD enriched with stevioside or rebaudioside A (2500 mg/kg BW) combined with L-arginine (2000 or 4000 mg/kg BW) and Cr(III) (1 or 5 mg/kg BW) for six weeks. The results showed that supplementation with SG (ST and RA) combined with L-arg and Cr(III) could improve blood glucose levels in rats with mild type 2 diabetes. Furthermore, ST was more effective in improving blood glucose levels, insulin resistance indices, and very low-density lipoprotein cholesterol (VLDL-C) concentrations than RA. Although L-arg and Cr(III) supplementation did not independently affect most blood carbohydrate and lipid indices, it further improved some biomarkers when combined, particularly with ST. Notably, the beneficial impact of ST on the homeostatic model assessment-insulin resistance (HOMA-IR) and on the quantitative insulin-sensitivity check index (QUICKI) was strengthened when mixed with a high dose of L-arg, while its impact on antioxidant status was improved when combined with a high dose of Cr(III) in rats with mild type 2 diabetes. In conclusion, these results suggest that supplementary stevioside combined with L-arginine and Cr(III) has therapeutic potential for mild type 2 diabetes. However, further studies are warranted to confirm these effects in other experimental models and humans.

The Potential of L-Arginine in Prevention and Treatment of Disturbed Carbohydrate and Lipid Metabolism-A Review.

L-arginine, an endogenous amino acid, is a safe substance that can be found in food. The compound is involved in synthesis of various products responsible for regulatory functions in the body. Particularly noteworthy is, among others, nitric oxide, a signaling molecule regulating carbohydrate and lipid metabolism. The increasing experimental and clinical data indicate that L-arginine supplementation may be helpful in managing disturbed metabolism in obesity, regulate arterial blood pressure or alleviate type 2 diabetes symptoms, but the mechanisms underlying these effects have not been sufficiently elucidated. This review aims to present the up-to-date information regarding the current uses and health-promoting potential of L-arginine, its effects on nitric oxide, carbohydrate and lipid metabolisms, based on the results of in vivo, in vitro studies, and clinical human trials. Available literature suggests that L-arginine may have beneficial effects on human health. However, some studies found that higher dietary L-arginine is associated with worsening of an existing disease or may be potential risk factor for development of some diseases. The mechanisms of regulatory effects of L-arginine on carbohydrate and lipid metabolism have not been fully understood and are currently under investigation.

Antimicrobial Activities Evaluation and Phytochemical Screening of Some Selected Plant Materials Used in Traditional Medicine.

Plant extracts are a source of valuable ingredients that can be used in many industries. This paper presents research on the content of selected bioactive compounds in extracts obtained from various plant materials. Raw materials have a documented use in traditional medicine not only in Poland. The tested plants were: bitter melon (fruit), elderberry (flowers, fruit, leaves), wild rose (fruit, flesh, seeds), mountain ash (fruit), guelder rose (fruit), and sea buckthorn (fruit, leaves, pomace). The main goal of these tests is to indicate the potential raw materials that may constitute an alternative source of bioactive compounds with antimicrobial activity. The plant material was tested for the content of bioactive antioxidant compounds and possible antimicrobial activity. The content of polyphenols (phenolic acids and flavonoids) was analyzed using UPLC/PDA, sterols, organic acids, and other bioactive compounds. The minimum inhibitory concentration (MIC) was determined. The total free phenolic acids (TPC) and total free flavonoids (TFC) of all plant raw materials was varied and ranged from 0.21 (mg RUTE/1 g of extract) to 38.30 mg RUTE/1 g of extract) for TFC. The concentration of sterols was, on average, about 10 mg/1 g of extract. The value of approx. 20 mg/1 g of the extract was recorded for bitter melon and beach rose. The content of organic acids was about 1.5 mg/1 g of the extract to even 13 mg/1 g of the extract for sea buckthorn berries. The most sensitive to the extracts' activity were the following bacteria: M. luteus, P. mirabilis, P. fragii, S. enteritidis, and E. coli. The tested plant materials can be used in various industries as a source of bioactive compounds of an antibacterial nature.

Sambucus Nigra Extracts-Natural Antioxidants and Antimicrobial Compounds.

Due to the health-promoting properties of elderberry fruits, which result from their rich chemical composition, this raw material is widely used in herbal medicine and the food industry. The aim of the study was to demonstrate the antibacterial activity of the elderberry fruit extracts. The research showed that the content of phenolic acids and flavonoids in the extracts determined their antibacterial activity. The research showed that the content of phenolic acids and flavonoids in the extracts determined their antibacterial activity. The following phenolic acids were predominant: chlorogenic acid, sinapic acid, and t-cinnamic acid. Their average content was, respectively, 139.09, 72.84, 51.29 mg/g extract. Rutin and quercetin (their average content was 1105.39 and 306.6 mg/g extract, respectively) were the dominant flavonoids. The research showed that the elderberry polyphenol extracts exhibited activity against selected strains of bacteria within the concentration range of 0.5-0.05%. The following bacteria were the most sensitive to the extracts: Micrococcus luteus, Proteus mirabilis, Pseudomonas fragii, and Escherichia coli. Of the compounds under analysis, apigenin, kaempferol and ferulic, protocatechuic, and p-coumarin acids had the greatest influence on the high antibacterial activity of elderberry extracts. The results of the microbiological and chemical analyses of the composition of the extracts were analyzed statistically to indicate the bioactive compounds of the greatest antimicrobial significance.

Comparison of the In Vitro Bioavailability of Selected Minerals from Gluten-Free Breads Enriched with Grains and Synthetic Organic and Non-Organic Compounds.

INTRODUCTION: Despite the constant efforts of scientists to improve the texture, sensory properties, and nutritional value of gluten-free bread, obtaining high bioavailability of minerals is still a huge challenge. Gluten-free bakery products are characterized by a low bioavailability of minerals. The aim of this study was to design gluten-free bread with high bioavailability of minerals commonly found in deficiencies in people struggling with gluten intolerance. MATERIAL AND METHODS: The material consisted of gluten-free breads designed to obtain the highest possible content of minerals in the bread while maintaining a good structure and taste. RESULTS: Higher contents of all the analyzed minerals were obtained in breads with natural and synthetic additives, both in rice and buckwheat bread, compared to basic bread. There was also a higher content of the analyzed minerals in buckwheat bread in comparison to rice bread for each type of additive. Higher bioavailability of iron, copper, calcium, and magnesium was noted in rice bread, while the bioavailability of zinc was higher in buckwheat bread. CONCLUSION: The additives used increased the bioavailability of the analyzed minerals from the gluten-free breads. The use of various variants of flour (rice, buckwheat) influenced the bioavailability of iron, zinc, copper, calcium, and magnesium. The release of minerals from gluten-free bread depends on the element and added components (seeds or synthetic additives).

Effects of Bitter Melon and a Chromium Propionate Complex on Symptoms of Insulin Resistance and Type 2 Diabetes in Rat Models.

Trivalent chromium (Cr) and bitter melon (Momordica charantia L., BM) have been shown to independently interact with the insulin signaling pathway leading to improvements in the symptoms of insulin resistance and diabetes in some animal models and human subjects. The aim of this study was to examine whether the combination of the two nutritional supplements could potentially have additive effects on treating these conditions in high-fat-fed streptozotocin (STZ)-induced diabetic rats. The experiment was conducted with 110 male Wistar rats divided into eleven groups and fed either a control or high-fat diet for 7 weeks. Half of the rats on the high-fat diet were injected with STZ (30 mg/kg body mass) to induce diabetes. The high-fat (HF) diets were then supplemented with a combination of Cr (as chromium(III) propionate complex, Cr3: either 10 or 50 mg Cr/kg diet) and bitter melon (lyophilized whole fruit: either 10 or 50 g/kg diet) for 6 weeks. After termination of the experiment, blood and internal organs were harvested for blood biochemical, hematological, and mineral (Cr) analyses using appropriate analytical methods. It was found that neither Cr(III) nor BM was able to significantly affect blood indices in HF and diabetic rats, but BM tended to improve body mass gain, blood glucose, and LDL cholesterol values, but decreased Cr content in the liver and kidneys of the Cr-co-supplemented type 2 diabetic model of rats. Supplementary Cr(III) had no appreciable effect on glucose and lipid metabolism in high-fat-fed STZ-induced diabetic rats. Supplementary BM fruit powder had some observable effects on body mass of high-fat-fed rats; these effects seem to be dampened when BM was co-administered with Cr. Cr(III) and BM appear to act as nutritional antagonists when both administered in food, probably due to binding of Cr by the polyphenol-type compounds present in the plant material. Graphical Abstract.

A Comparative Study of the Bioavailability of Fe, Cu and Zn from Gluten-Free Breads Enriched with Natural and Synthetic Additives.

The aim of this study was to compare the bioavailability of iron, copper and zinc from newly designed gluten-free breads enriched with natural and synthetic additives. The study was conducted on rats with induced Fe, Cu and Zn deficiency. The nutritional intervention with diets supplemented with a 70% addition of gluten-free breads enriched with natural additives and organic compounds to the control diet AIN-93M lasted 40 days. After the intervention, the rats were euthanized, the organs were collected and their mineral content was measured. Chemical analysis of diets with the addition of fortified gluten-free breads showed significantly higher amounts of iron, zinc and copper in diets with the addition of fortified breads compared to diets with the addition of unenriched breads. The type of additives did not influence the amount of minerals in diets. It is necessary to conduct further research to explain the interactions of ingredients and the factors affecting the bioavailability of Fe, Cu and Zn from gluten-free breads in order to obtain a product with a high bioavailability of these ingredients.

Chromium(III) Glycinate Complex Supplementation Improves the Blood Glucose Level and Attenuates the Tissular Copper to Zinc Ratio in Rats with Mild Hyperglycaemia.

The aim of the study was to evaluate the hypoglycaemic potential of supplementary Cr in the form of chromium(III) glycinate (CrGly) in the diabetic model of rats. The experiment was conducted on 40 male Wistar rats, of which 30 were made diabetic by injection of a single dose of streptozotocin (55 mg/kg b.m.), while the remaining 10 rats served as the healthy control. After inducing hyperglycaemia, 2 groups of diabetic rats (10 rats each) were supplemented with Cr either as CrGly or chromium(III) picolinate (CrPic) given orally at a dose of 10 mg/kg diet (about 0.75 mg Cr/kg b.m.) with adequate AIN-93M diet for 7 weeks. At the termination of experiment, all animals were sacrificed to collect blood and internal organs for biochemical assays. Blood biochemical indices and tissular trace element contents (Fe, Zn, Cu, Cr) were measured and compared with the values of the untreated groups. It was found that CrGly significantly decreased blood glucose, total cholesterol, HDL cholesterol and triacylglycerol levels more efficiently than CrPic. Furthermore, both Cr compounds normalized disturbed the serum, renal and cardiac molar Cu/Zn ratio, as well as restored the kidney Zn and Cu levels in rats with hyperglycaemia. Supplementary Cr did not increase the tissular Cr levels in diabetic rats. The study confirmed the hypoglycaemic potential of CrGly in the diabetic model of rats.

Steviol Glycosides Supplementation Affects Lipid Metabolism in High-Fat Fed STZ-Induced Diabetic Rats.

A number of health-promoting properties of Stevia rebaudiana Bertoni and its glycosides, including the antihyperglycemic activity, have been found. The mechanisms of the antidiabetic action of stevia have not been fully understood. The aim of this study was to evaluate the effects of supplementary steviol glycosides on high-fat fed streptozotocin-induced diabetic rats with particular attention to lipid metabolism. The experiment was conducted on 70 male Wistar rats, of which 60 were fed a high-fat diet for 8 weeks followed by intraperitoneal injection of streptozotocin, to induce type 2 diabetes. Afterwards, rats were divided into six groups and fed a high-fat diet supplemented with pure stevioside or rebaudioside A, at two levels (500 or 2500 mg/kg body weight (b.w.)) for 5 weeks. Three additional groups: diabetic untreated, diabetic treated with metformin, and healthy, served as respective controls. Blood and dissected internal organs were collected for hematological, biochemical, and histopathological tests. It was found that dietary supplementation with steviol glycosides did not affect blood glucose, insulin, and insulin resistance indices, antioxidant biomarkers, but normalized hyperlipidemia and affected the appetite, as well as attenuated blood liver and kidney function indices, and reduced tissular damage in diabetic rats. Steviol glycosides normalize lipid metabolism and attenuate internal organs damage in diabetes.

The Relationship between Dietary, Serum and Hair Levels of Minerals (Fe, Zn, Cu) and Glucose Metabolism Indices in Obese Type 2 Diabetic Patients.

The aim of this study was to assess the levels of Zn, Fe and Cu in the serum and hair, and dietary intake of type 2 diabetic patients and their association with glucose and lipid indices. The study was conducted on 62 people aged 40-78 years (31 diabetic patients and 31 healthy subjects, who were the control group). The content of trace elements in the hair and serum was analysed with the AAS method. The serum insulin, HbA1c, glucose, total cholesterol and triacylglycerol concentrations were measured by means of RIA, HPLC and colorimetric methods, respectively. The diabetic patients were found to have significantly higher dietary iron intake, higher hair Fe and lower serum Zn concentrations than the non-diabetic subjects, while the hair Zn and Cu contents were comparable in both groups. The serum Zn and Cu levels of the diabetic subjects were negatively correlated with the serum glucose, the serum Zn and Cu/Zn ratio was inversely correlated with the serum total cholesterol and the serum insulin level was positively associated with the hair Cu/Zn ratio. The results of this study indicate that the trace element status (Zn, Fe, Cu), as reflected in the blood serum and hair, may be disturbed due to metabolic derangement occurring in diabetes.

Chia seeds (Salvia hispanica): health promoting properties and therapeutic applications ­ a review

Chia has been known for over 5,500 years. Chia seeds were one of the most important components of the diet of Mayas and Aztecs. The chemical composition and technological properties of chia give the plant a high nutritional potential. Chia is a good source of polyunsaturated fatty acids: omega-3 and omega-6, soluble dietary fiber. It also contains appreciable amount of proteins and phytochemicals. Nutritional value of chia is the reason why it is used in prophylaxis of several non-infectious diseases such as obesity, hypertension, cardiovascular diseases (CVDs), cancer and diabetes. Nutritional and therapeutic aspects of chia are currently being researched by many scientific centres. The aim of this article is to present the nutritional and therapeutic values of chia.

The Effects of Supplementary Cr3 (Chromium(III) Propionate Complex) on the Mineral Status in Healthy Female Rats.

More and more people use food supplements for various reasons, e.g. to prevent mineral deficiency and diseases (e.g. osteoporosis, diabetes, anaemia). Supplements containing Cr(III) are purchased primarily for weight loss and antidiabetic effects. The aim of this study was to evaluate the effects of supplementary Cr3 {chromium(III) propionate complex, [Cr3O(O2CCH2CH3)6(H2O)3]NO3)} on the mineral status in female Wistar rats. The study was carried out on 30 female Wistar rats, divided into five groups (six animals in each): a control group and test groups fed Cr3 supplemented diets with 100, 200, 500 and 1000 mg Cr · kg-1 diet (equivalent to 10, 20, 50 and 100 mg Cr ·kg-1 body mass (b.m.) per day) given as Cr3 for 4 weeks. Supplementary Cr3 increased the Cr content in tissues in a dose-dependent manner. High dietary doses of Cr3, 20 and 100 mg Cr · kg-1 b.m., increased the Cu content in the liver and spleen as well as the Zn content in the kidneys but decreased the liver Ca content. Doses of 50-100 mg Cr ·kg-1 b.m. decreased the serum Fe concentration and the Fe content in the liver and kidneys. Supplementation with Cr3 at doses of 10 and 100 mg Cr ·kg-1 b.m. did not affect the Mg content in the rats' tissues. In conclusion, high dietary doses of Cr3 (10 and 100 mg Cr· kg-1 b.m.) given for 4 weeks affected the mineral status of Fe, Zn, Cu and Ca in the tissues of healthy female Wistar rats.

Effect of Elderberry (Sambucus nigra L.) Extract Supplementation in STZ-Induced Diabetic Rats Fed with a High-Fat Diet.

Elderberry (Sambucus nigra L.) lipophilic and polar extract dietary supplementation effects were evaluated according to diabetes management indices, using an in vivo model. A research pipeline was constructed, that ranged from extract preparation, partial chemical characterization and toxicity evaluation, to examining the elderberry extract dietary supplementation effects on biofluid and tissues. Extracts toxicity was screened using an Aliivibrio fischeri bioluminescence model. A concentration of up to 60 mg/L was selected, and rat doses for oral supplementation were computed applying the interspecies correlation between A. fischeri and rats. Wistar type 2 diabetic rats, induced by streptozotocin (STZ), were fed a high-fat diet and supplemented for 4 weeks at doses of 190 and 350 mg/kg body weight/day of lipophilic and polar extract, respectively. As far as we know, lipophilic elderberry extract supplementation was assessed for the first time, while polar extract was administrated at higher doses and for a shorter period compared to previous studies, aiming to evaluate subacute supplementation effects. The polar extract modulated glucose metabolism by correcting hyperglycemia, while the lipophilic extract lowered insulin secretion. Both extracts lowered insulin resistance, without remarkable alterations to hematological indices, sera lipids and sera and tissular trace element homeostasis. In conclusion, elderberries are a potential source of bioactive compounds for formulations to be used as co-adjuvants in diabetes management.

Assessment of the nutritional value daily food rations of children aged 1-4 years.

BACKGROUND: An adequately balanced daily food rations (DFR) providing the organism with a sufficient amount of energy and nutrients, including minerals, is particularly important in infanthood and early childhood due to the child's intensive physical, intellectual and motoric development. OBJECTIVE: The aim of this study was to evaluation the supply of energy, nutrients and vitamins in daily food rations of children fed at home and in nursery schools. MATERIAL AND METHODS: 75 children aged 1-4 years were the research subjects. They were divided into three age subgroups: 12-24-month-olds, 25-36-month-olds and 37-48-month-olds. The daily consumption of energy and vitamins was assessed by means of a 7-day 24-hour nutritional interview made with current note taking and by means of a computer database (Dietetyk 2). Significant differences in the content of energy, nutrients and vitamins in the DFR were investigated using the two-way analysis of variance (Statistica 10.0) at significance level p≤0.05. RESULTS: Neither the children's sex nor age had influence on the intake of energy and macronutrients. Apart from the amount of energy (68-101.8% RDA) and proteins (183-288% RDA) these values were generally normal, but they had influence on the content of vitamins in the DFR. The DFR was characterised by generally excessive content of vitamins A, B(2), B(6) and B(12). However, in comparison with the RDA the intake was significantly higher in the DFR of the youngest children (12-24 months old). In the group aged 37-48 months there were significantly higher values in the intake of vitamins B(2) (317% vs 137% RDA) and B6 (334% vs 147% RDA). On the other hand, in comparison with the RDA, the DFR provided too small amounts of vitamins D, E, folates and vitamin C. The DFR of the youngest children (12-24 months old) contained significantly greater amounts of vitamins: D (41.3% vs 16.2% RDA), E (83.6% vs 63.5% RDA) and C (102.0% vs 48.6% RDA), as compared with the children aged 37-48 months. Only the content of vitamins B(1) and PP in the children's DFR was similar or slightly greater than the RDA. CONCLUSIONS: The intake of energy in the DFR of the children aged 1-4 years was generally comparable, but in the children aged 37-48 months it did not satisfy the daily demand. In all the age groups under study the supply of macronutrients satisfied about 100% of the demand, whereas the supply of protein and sucrose was excessive. The children aged 12-24 months consumed more vitamins D, E, B(2), PP, B(6), B(12), C than the children aged 37-48 months. The supply of vitamins D, E, C and folates was too low, whereas the consumption of vitamins: B(2), B(6) and B(12) exceeded the recommended daily intake.

Iron bioavailability from cereal products enriched with Pleurotus ostreatus mushrooms in rats with induced anaemia.

INTRODUCTION AND OBJECTIVE: Oyster mushroom Pleurotus ostreatus is good source of iron. However, there is a limited data concerning bioavailability of iron from oyster mushroom and also cereal products containing this mushroom. The aim of this study was to assess bioavailability of iron from products with an addition of Pleurotus ostreatus in male rats with anaemia. MATERIAL AND METHODS: Investigations were conducted in two stages. In the first stage iron deficiency was developed in rats. For this purpose 6 weeks old 36 male Wistar rats were fed a AIN-93M diet deficient in iron and 6 males received a standard AIN-93M diet. In the second stage of the study the assessment of Fe bioavailability from cereal products enriched with dried Pleurotus ostreatus. After experiment the animals were killed and blood and heart, liver, spleen and kidneys were collected for biochemical tests. RESULTS: Feeding male Wistar rats supplemented with dried Pleurotus ostreatus mushrooms diets resulted in the restitution of the systemic Fe level, as manifested by an increase of the level comparable to the control group for: iron transferrin saturation rate, haemoglobin and mean corpuscular volume. Values of hematocrit, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration in animals fed products supplemented with Pleurotus ostreatus were significantly higher compared to animals fed products with no Fe added. The highest MCV value was recorded when 20% of dried oyster mushrooms were added. Iron levels in the blood serum, the liver and kidneys in animals fed cereal products considerably exceeded values recorded at the beginning of the experiment and were similar to the control values. CONCLUSIONS: Product may be a valuable source of iron in the nutrition of individuals with a deficiency of this element, first of all patients with absorption and metabolism disorders, but also may add variety to the traditional daily diet.

The Effects of Supplementary Mulberry Leaf (Morus alba) Extracts on the Trace Element Status (Fe, Zn and Cu) in Relation to Diabetes Management and Antioxidant Indices in Diabetic Rats.

Mulberry leaves (Morus alba) have been used in folk medicine to mitigate symptoms of diabetes. The mulberry plant contains phenolic compounds that are able to decrease blood glucose concentration. Since various phenolics have antioxidant and metal binding properties, they can be used to alleviate oxidative stress and chelate trace elements involved in redox reactions. The aim of this study was to evaluate the effects of dietary supplementation with mulberry leaf extracts (acetone-water (AE) and ethanol-water (EE)) on the trace element status (Fe, Zn and Cu) in relation to diabetes management and antioxidant indices in high-fat diet-fed/STZ diabetic rats. The experiment was performed on 38 male Wistar rats with diabetes (induced by high-fat diet (HF) and streptozotocin injection) or the control fed with AIN-93M or high-fat diet. As a result, five experimental groups were used: (1) a healthy control group fed with AIN-93M; (2) an HF control group; (3) a diabetic HF group; (4) a diabetic HF + AE group (6 g/kg diet); (5) a diabetic HF + EE group (6 g/kg diet). The rats were fed with appropriate diets for 4 weeks. The content of trace elements (Fe, Zn and Cu) in the serum and tissues was measured by means of atomic absorption spectrometry (AAS). Biochemical analyses (glucose, TBARS, FRAP) were performed on the blood serum. It was shown that the AE decreased hepatic and renal Fe stores, while the EE increased hepatic Cu levels in diabetic rats and confirmed their ability to regulate the Fe and Cu status in diabetes. The results confirmed a significant hypoglycaemic and antioxidant potential of both mulberry leaf extracts in diabetic rats.

An Assessment of the Consumption of Energy and Selected Minerals and Their Content in the Hair of Children Aged 1-4 Years.

The aim of this study was to assess the consumption of energy and selected minerals (Ca, Mg, Fe, Zn, Cu) and their content in the hair of children aged 1-4 years. Seventy-five children were divided into three age subgroups: 12-24-month-olds, 25-36-month-olds and 37-48-month-olds. The data on energy intake and consumption of nutrients were obtained by means of a nutritional interview. The content of elements in the hair was measured by means of flame atomic absorption spectrometry (AAS) with an AAS-3 spectrophotometer (Zeiss). The daily food rations of children aged 12-36 months were characterised by adequate energy value, but the values of Ca and K were too low, whereas the content of Mg, Zn and Cu was high. On the other hand, the daily food rations of children aged 37-48 months provided sufficient amounts of Mg and Zn, but the value of Cu was too high, whereas energy, Ca, K and Fe were too low. About 42.7% of the children under study were characterised by an abnormal state of nutrition. An inadequately balanced diet needs to be corrected by educating parents or guardians in appropriate nutrition. There are significant correlations (r > 0.9) between the supply of Ca in the diet of children aged 1-4 years and the content of this element in their hair.

The Effects of High Dietary Doses of Chromium(III) Complex with Propionic Acid on Nutritional and Selected Blood Indices in Healthy Female Rats.

People taking dietary supplements are usually determined to lose weight, supplement nutrition or reduce the risk of illness and negative effects of their state of health. Chromium(III) supplementation influence body composition and mass, glucose and lipid metabolism and it enhance insulin action. This fact could be of general interest because diabetes mellitus is an increasing health problem in many countries. The study describes the effects of high dietary doses of chromium(III) complex with propionic acid [Cr3] (from 100 to 1000 mg Cr · kg(-1) diet) on the organisms of healthy female rats, with special regard to overall nutritional, carbohydrate, lipid and blood biochemical and morphological and haematological indices. The study was carried out on 30 10-week-old female Wistar rats, which were divided into five equal groups (six animals in each): the control group and four groups of tested animals which had free access to the diet supplemented with 100, 200, 500 and 1000 mg Cr · kg(-1) (equivalent of 10, 20, 50 and 100 mg Cr · kg body weight (b.w.) · day(-1)), given as [Cr3O(O2CCH2CH3)6(H2O)3]⋅NO3, also known as Cr3, for 4 weeks. There were no significant differences in body mass gains, feeding efficiency ratio, internal organ masses or blood serum glucose concentrations, except for some changes in the serum triglycerides concentration, which decreased in the rats that received 500 and 1000 mg Cr · kg(-1) diet, as opposed to the group treated with 200 mg Cr · kg(-1) diet. The dietary supplementation of Cr3 for 4 weeks at doses of 100 to 1000 mg Cr · kg(-1) diet did not affect overall nutritional indices and most blood biochemical, morphological and haematological indices.

Effect of L-arginine supplementation on insulin resistance and serum adiponectin concentration in rats with fat diet.

OBJECT: The purpose of this study was to determine whether supplementation with L-arginine, a substrate used in the production of nitric oxide, had an effect on adiponectin concentration in rats fed a high-fat diet. The influence of L-arginine on insulin resistance was also evaluated. MATERIALS AND METHODS: The experiment was performed using 36 Wistar rats divided into three groups: group 1 was fed a standard diet, group 2 a high-fat (HF) diet, group 3 a HF diet supplemented with L-arginine. After 42 days, serum levels of lipids, glucose, insulin, NO, and adiponectin were measured. Insulin resistance (IR) was estimated by the Homeostasis Model Assessment (HOMA). RESULTS: Body mass was equal in all 3 groups, at the beginning as well as at the end of the study, however, in group 2 the amount of visceral fat was greater after 42 days. In group 3, there was a tendency for visceral fat to decrease. An increase in cholesterol, triglycerides, insulin and HOMA-IR, as well as a decrease in NO and adiponectin were seen in group 2, while in group 3, L-arginine supplementation ameliorated these disturbances. CONCLUSIONS: Our study shows that L-arginine supplementation in rats fed a HF diet is associated with an increase in insulin sensitivity. Our findings suggest that the underlying mechanism could be at least partially related to an increase in adiponectin concentration.