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Relationships between diet, sex hormone concentrations, and the estrous cycle are important from the perspective of infertility and estrogen-dependent disease prevention and treatment. Four dietary interventions reflecting modern eating behaviors were explored. The study involved 50 female rats divided into five feeding groups. The impact of the amount of sucrose consumed (9% and 18% of the dietary energy content), alternating high-sucrose and sucrose-free diets, and a high-sucrose diet combined with intermittent one-day fasting on the estrous cycle and sex hormone concentrations in female rats was assessed. Even low amounts of dietary sucrose (9% of the dietary energy content) were found to lead to increased estradiol (E2) concentrations and decreased progesterone (Pg) concentrations. A high-sucrose diet, even when periodically applied, additionally led to a reduced concentration of luteinizing hormone (LH). The largest changes in the hormones tested were observed with one-day fasting coupled with the high-sucrose diet; in addition, the estrous phase was shortened and the estrous cycle was disrupted. The results of this study show that both the amount of dietary sucrose and also its uptake pattern affect the estrous cycle and sex hormone concentrations in female rats.

The aim of the study was to assess the effect of different models of sucrose intake on carbohydrate-lipid metabolism and changes in oxidant balance in the ovaries and uterus of rats. Animals were divided into three groups: I—basic feed, II—feed contains 8% of sucrose, III—alternately every second week the basic feed and modified feed contains 16% of sucrose. The diet containing 8% of sucrose was found to result in an increased activity of antioxidant enzymes in the blood, with unchanged malonylodialdehyde concentration. Variable sucrose administration pattern intensified oxidative stress in the blood and led to disturbed redox equilibrium in the rat uterus, even at a comparable long-term sucrose uptake as in the group II. This was manifested as a reduced superoxide dismutase activity (in the blood and uterus) and a higher malonylodialdehyde concentration (in the uterus). The changes observed could have been a result of metabolic disorders (higher amount of visceral fat, higher glucose concentration, higher index of homeostasis model assessment of insulin resistance, and reduced HDL-cholesterol concentration) and endocrine disorders (higher oestrogen concentrations). Changes in the antioxidant status in the rats kept on the alternating diet, may underpin the failure of fertilised egg implantation in the uterine tissue and pregnancy completion.

The effect of a sucrose diet and repeated one-day starvation on oxidative status in the ovary and uterus is still unknown. Our analysis focused on carbohydrate-lipid metabolism parameters and the changes in red blood cells, ovary and uterus superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities and malonylodialdehyde (MDA) concentration in rats fed with a diet containing 16% of sucrose and subjected to systematic one-day starvation when using such a diet. It was found that a diet with 16% sucrose contributed to the increase of antioxidant enzyme activity in the blood (GPx and CAT) and uterus (SOD), without changes in MDA concentrations, which indicates an increase in reactive oxygen species (ROS) concentration in these tissues, being balanced by an increase in antioxidant enzyme activity. The introduction of a regular one-day starvation period into the diet intensified oxidative stress and led to a redox imbalance in the reproductive tissues of female rats. This was manifested by higher GPx activity, lower CAT activity and higher MDA concentration in the uterus and lower GPx and CAT activities and lower MDA concentration in the ovaries. The observed changes may be the cause of fertility disorders and possible problems with fertilised egg cell implantation into the uterine tissue.

Background Studies on the effects of high fructose corn syrup (HFCS) on the metabolism are scarce and their results are inconsistent. Objectives The aim of this research was to examine in an animal model the effect of replacing sucrose with HFCS-55 on the levels of glucose, insulin and leptin, and on the consumption of feed, body weight gain and fat storage. Material and methods The experiment was carried out on 30 Wistar male rats aged 5 months, fed 3 different diets, containing whole grains (group I), 10% sucrose (group II) and 10% HFCS (group III). Results It was found that the amount of daily energy intake was similar for all the groups of animals. There was no difference in fasting glucose and insulin level and homeostatic model assessment for insulin resistance (HOMA-IR) index. The higher leptin level was determined in blood plasma of the animal fed a feed with sucrose (group 2) compared to group 1 and group 3 (360 ng/mL vs 263 and 230 ng/mL, respectively). Despite the similar amounts of consumed energy, the animals fed with modified feeds achieved higher weight gain and the effect of HFCS-55 was similar to the effect of sucrose. Conclusions The obtained results indicate similar metabolic effects of HFCS-55 and sucrose in feed, at the level of 11% dietary energy value, on the energy intake, body weight gain and periorgan adipose tissue accumulation in rats. The results suggest that accusations against HFCS as the major dietary contributor to overweight and obesity are unfounded, and the total elimination of HFCS from the diet seems to be unnecessary. The modified feeds (containing both sucrose and HFCS) produced greater absolute weight gain and weight gain per kilojoule consumed compared to standard feeds. This may indicate not just a basic thermodynamic consequence of consuming more energy, but a change in the metabolic efficiency when consuming a diet with simple sugars and refined carbohydrates.

Background. Over the past 50 years, the average consumption of sugar worldwide has tripled, also the type of consumed sugar has changed. Due to high price of sucrose and its technological disadvantages, high fructose corn syrup (HFCS) has become one of the most commonly used substitutes. Objective. The aim of the study was to compare, on the animal model, the effect of sugar type (sucrose vs high fructose corn syrup 55% of fructose) and the sugar form (solid vs fluid and solid) on the chosen parameters of carbohydrate-lipid metabolism. Material and methods. The experiment was carried out on 40 Wistar male rats aged 5 months, fed four isocaloric diets, containing: group I (SUC 15%) fodder with 15% sucrose, group II (HFCS 15%) fodder with 15% HFCS-55%, group III (SUC 7.5%+7.5%) – 7.5% sucrose in solid fodder and 7.5% sucrose water solution, group IV (HFCS 7.5%+7.5%) – 7.5% HFCS-55% in solid fodder and 7.5% HFCS water solution. Results. The effect of HFCS-55 on the parameters of carbohydrate and lipid metabolism was not equivalent of the effect of sucrose. Dietary use of HFCS-55 instead of sucrose causes adverse changes in blood parameters of carbohydrate and lipid metabolism, particularly when provided in beverages, as at comparable weight gains to that of sucrose. More intense changes, manifesting in increased blood levels of glucose, triglycerides and uric acid, as well as increased liver fat content, were observed at simultaneous intake of sweeteners in solid foods and fluids, even with less sugar consumption, compared to solid food only. Conclusions. Dietary use of HFCS-55 causes adverse changes in blood parameters of carbohydrate and lipid metabolism, as at comparable weight gains to that of sucrose. But liquid form of sugar intake is more important insulin resistance and cardiovascular disease risk factor than the sugar type.

Background The objective of this study was to compare, in an animal model, the effect of different sugar types (sucrose vs. high-fructose corn syrup 55%) consumed as 10% by weight of the diet (11.6% of daily caloric intake) on the amount of food consumed, body weight, fatty tissue deposits, concentrations of selected lipids, and atherogenic indices of blood plasma. Material and method. The experiment was carried out on 30 5-month-old Wistar male rats, fed three differ- ent diets, containing, amongst other foods, (1) ground unrefined cereal grains, (2) sucrose, (3) high-fructose corn syrup. Results. Weight gains in animals on sucrose or high-fructose corn syrup diets were higher than those con- suming basic feed, but the effect was not associated with perivisceral fat accumulation. It has been found that all the atherogenic indices (Castellirs Risk Index I, Castellirs Risk Index II, Atherogenic Index of Plasma, Atherogenic Coefficient) were statistically significantly higher in animals on a high-fructose corn syrup diet compared to both the control group and those on a sucrose diet. Conclusion. The effect of the 55% high-fructose corn syrup on the tested parameters of lipid metabolism was not equivalent to that of sucrose. Using HFCS-55 instead of sucrose has an adverse effect on blood lipid parameters, while weight gains and peri-organ fat deposits are comparable. Moreover, the obtained results confirm that tested animals were susceptible to the adverse effects of sugars added to their diet, even in small amounts. This emphasises the need to precisely control the amount of added sugars in. Methods nd. The objective of this study was to compare, in an animal model, the effect of different sugar types (sucrose vs. high-fructose corn syrup 55%) consumed as 10% by weight of the diet (11.6% of daily caloric intake) on the amount of food consumed, body weight, fatty tissue deposits, concentrations of selected lipids, and atherogenic indices of blood plasma. Material and method. The experiment was carried out on 30 5-month-old Wistar male rats, fed three differ- ent diets, containing, amongst other foods, (1) ground unrefined cereal grains, (2) sucrose, (3) high-fructose corn syrup. Results Weight gains in animals on sucrose or high-fructose corn syrup diets were higher than those con- suming basic feed, but the effect was not associated with perivisceral fat accumulation. It has been found that all the atherogenic indices (Castellirs Risk Index I, Castellirs Risk Index II, Atherogenic Index of Plasma, Atherogenic Coefficient) were statistically significantly higher in animals on a high-fructose corn syrup diet compared to both the control group and those on a sucrose diet. Conclusions The effect of the 55% high-fructose corn syrup on the tested parameters of lipid metabolism was not equivalent to that of sucrose. Using HFCS-55 instead of sucrose has an adverse effect on blood lipid parameters, while weight gains and peri-organ fat deposits are comparable. Moreover, the obtained results confirm that tested animals were susceptible to the adverse effects of sugars added to their diet, even in small amounts. This emphasises the need to precisely control the amount of added sugars in the diet.

Hepatic encephalopathy (HE), a consequence of liver damage, is associated with cognitive deficits. In this study, behavioral activity, non-associative learning, associative memory, cognitive coordination and flexibility were investigated in rats with subclinical HE evoked by thioacetamide treatment. Non-associative learning was studied in the open field (OF) set up in 12 HE and 8 saline-injected control rats (C). Memory was examined in spatial place avoidance tasks in 10 HE and 10 C rats. The Room+ Arena- task involved the selection of distal room stimuli from irrelevant arena stimuli (i.e. intramaze cues and/or self-motion information), which engages processes of cognitive coordination. Following the Room+ Arena- training, cognitive flexibility of rats was tested in the Arena+ place avoidance condition, which demands the previously ignored stimuli from arena. In the OF test HE and control rats behaved similar. They displayed high activity in the first block of each session and this pattern was stable. In both groups of rats darkness enhanced locomotor activity in comparison to light only in the first block. The HE and C rats avoided the to-be-avoided place in the Room+ Arena- task, whereas only HE rats were affected in the Arena+ task. In conclusion, these results demonstrate cognitive inflexibility in HE rats. We suggest that (1) the behavioral changes in the TAA model are typical of subclinical HE and (2) test for cognitive flexibility may be modified towards a routine use in patients with subclinical HE.

Metabolic processes of food additives which are "exogenous xenobiotics" are catalysed, primarily, by enzymes located in microsomes of hepatocytes affiliated to P-450 cytochrome superfamily, containing iron. The aim of the study was to investigate the effect of diet composition and selected food additives on the erythrocyte system and iron metabolism in peripheral blood of male rats.The experiment was carried out on 30 male rats sorted into three equinumerous groups. For drinking animals received pure, settled tap water, animals from group III were receiving additionally an aqueous solution of sodium (nitrate), potassium nitrite, benzoic acid, sorbic acid and monosodium glutamate.Ascertained a significant effect of changes in diet composition on the increase in hematocrit marker value and the count of red blood cells in blood of animals examined. Used food additives diminished hemoglobin concentration, hematocrit value and red blood cell count, diminishing also iron concentration in serum, the total iron binding capacity and transferrin saturation with iron.Analysis of the results allowed ascertain adverse changes in values of the erythrocytic system markers, occurring under the influence of the applied mixture of food additives. Used food additives change the iron metabolism, most likely from the necessity of applied xenobiotics biotransformation by heme-containing monoxygenases of P-450 cytochrome.

The aim of the study was to estimate, on an animal model, the influence of diet composition and its supplementation with selected B vitamins on distribution of calcium and magnesium in the body. The change in diet composition was found to significantly reduce the calcium contents in the liver and blood of males as well as in the liver and kidney of females. The change enhanced calcium and magnesium accumulation in the skeletal muscles of the animals examined. In females, the effect was augmented by supplementation. The vitamin supplementation applied was conducive to incorporation into the bones calcium in males and magnesium in females, respectively. Analysis of the results allows to conclude that both the change in the diet composition and the supplementation of the diet modified by selected B vitamins significantly affected distribution of calcium and magnesium between different organs and tissues of the animals examined and probably modified the functional status of the organs and tissues in question. The magnitude and direction of the changes in most parameters analysed were sex-dependent.

BACKGROUND. The animal model study was aimed at evaluating the effect of diet composition and energy drink intake on body weight, accumulation and distribution of deposited fatty tissue, and concentrations of glucose and triacylglycerols in blood plasma.The experiment was carried out on 30 male rats. The animals were sorted into three groups, fed on group I - standard feed, groups II and III - modified feed, in which part of whole wheat and corn grains were isocalorically substituted with wheat flour and saccharose. Animals from groups I and II were receiving settled tap water for drinking, whereas these from group III were administered 3 ml of an energy drink, and then were provided drinking water.In analysing the results obtained it was stated that the addition of the energy drink to diet affected diminished body weight gains of the animals (per energy unit in the diet) as compared to the group of animals fed modified diet. The animals receiving the energy drink were additionally characterised by a lower content of peri-intestinal and intramuscular fatty tissue, whereas were found to deposit significantly higher amounts of peri-cardiac fatty tissue. Samples of blood plasma of these animals were found to contain a significantly higher concentration of glucose, compared to those of the animals fed modified diet. In turn, the concentration of triacylglycerols was comparable in all groups of animals.The analysis of results achieved enabled concluding that the addition of energy drink to diet was significantly modifying the rate and tendency of metabolic changes, which was manifested in: increased glucose concentration in blood plasma, diminished body weight gains of the animals and deposition of peri-cardial fat.