Feed Composition Differences Resulting from Organic and Conventional Farming Practices Affect Physiological Parameters in Wistar Rats-Results from a Factorial, Two-Generation Dietary Intervention Trial.

Recent human cohort studies reported positive associations between organic food consumption and a lower incidence of obesity, cancer, and several other diseases. However, there are very few animal and human dietary intervention studies that provide supporting evidence or a mechanistic understanding of these associations. Here we report results from a two-generation, dietary intervention study with male Wistar rats to identify the effects of feeds made from organic and conventional crops on growth, hormonal, and immune system parameters that are known to affect the risk of a number of chronic, non-communicable diseases in animals and humans. A 2 × 2 factorial design was used to separate the effects of contrasting crop protection methods (use or non-use of synthetic chemical pesticides) and fertilizers (mineral nitrogen, phosphorus and potassium (NPK) fertilizers vs. manure use) applied in conventional and organic crop production. Conventional, pesticide-based crop protection resulted in significantly lower fiber, polyphenol, flavonoid, and lutein, but higher lipid, aldicarb, and diquat concentrations in animal feeds. Conventional, mineral NPK-based fertilization resulted in significantly lower polyphenol, but higher cadmium and protein concentrations in feeds. Feed composition differences resulting from the use of pesticides and/or mineral NPK-fertilizer had a significant effect on feed intake, weight gain, plasma hormone, and immunoglobulin concentrations, and lymphocyte proliferation in both generations of rats and in the second generation also on the body weight at weaning. Results suggest that relatively small changes in dietary intakes of (a) protein, lipids, and fiber, (b) toxic and/or endocrine-disrupting pesticides and metals, and (c) polyphenols and other antioxidants (resulting from pesticide and/or mineral NPK-fertilizer use) had complex and often interactive effects on endocrine, immune systems and growth parameters in rats. However, the physiological responses to contrasting feed composition/intake profiles differed substantially between the first and second generations of rats. This may indicate epigenetic programming and/or the generation of "adaptive" phenotypes and should be investigated further.

Effects of Dietary Oat Beta-Glucans on Colon Apoptosis and Autophagy through TLRs and Dectin-1 Signaling Pathways-Crohn's Disease Model Study.

BACKGROUND: Crohn's disease (CD) is characterized by chronic inflammation of the gastrointestinal tract with alternating periods of exacerbation and remission. The aim of this study was to determine the time-dependent effects of dietary oat beta-glucans on colon apoptosis and autophagy in the CD rat model. METHODS: A total of 150 Sprague-Dawley rats were divided into two main groups: healthy control (H) and a TNBS (2,4,6-trinitrobenzosulfonic acid)-induced colitis (C) group, both including subgroups fed with feed without beta-glucans (ßG-) or feed supplemented with low- (ßGl) or high-molar-mass oat beta-glucans (ßGh) for 3, 7, or 21 days. The expression of autophagy (LC3B) and apoptosis (Caspase-3) markers, as well as Toll-like (TLRs) and Dectin-1 receptors, in the colon epithelial cells, was determined using immunohistochemistry and Western blot. RESULTS: The results showed that in rats with colitis, after 3 days of induction of inflammation, the expression of Caspase-3 and LC3B in intestinal epithelial cells did not change, while that of TLR 4 and Dectin-1 decreased. Beta-glucan supplementation caused an increase in the expression of TLR 5 and Dectin-1 with no changes in the expression of Caspase-3 and LC3B. After 7 days, a high expression of Caspase-3 was observed in the colitis-induced animals without any changes in the expression of LC3B and TLRs, and simultaneously, a decrease in Dectin-1 expression was observed. The consumption of feed with ßGl or ßGh resulted in a decrease in Caspase-3 expression and an increase in TLR 5 expression in the CßGl group, with no change in the expression of LC3B and TLR 4. After 21 days, the expression of Caspase-3 and TLRs was not changed by colitis, while that of LC3B and Dectin-1 was decreased. Feed supplementation with ßGh resulted in an increase in the expression of both Caspase-3 and LC3B, while the consumption of feed with ßGh and ßGl increased Dectin-1 expression. However, regardless of the type of nutritional intervention, the expression of TLRs did not change after 21 days. CONCLUSIONS: Dietary intake of ßGl and ßGh significantly reduced colitis by time-dependent modification of autophagy and apoptosis, with ßGI exhibiting a stronger effect on apoptosis and ßGh on autophagy. The mechanism of this action may be based on the activation of TLRs and Dectin-1 receptor and depends on the period of exacerbation or remission of CD.

Beneficial Effects of Oat Beta-Glucan Dietary Supplementation in Colitis Depend on its Molecular Weight.

BACKGROUND: Inflammatory bowel diseases are an important health problem. Therefore, the aim of the present study was to compare the impact of isolated oat beta-glucan fractions of low and high molecular weight, taken as dietary supplementation, on inflammatory markers in the colitis model. METHODS: Two groups of Sprague-Dawley rats-control and with experimentally induced colitis-were subsequently divided into three subgroups and fed over 21 days feed supplemented with 1% of low (ßGl) or high (ßGh) molecular weight oat beta-glucan fraction or feed without supplementation. The level of colon inflammatory markers, cytokines, and their receptors' genes expressions and immune cells numbers were measured by ELISA, RT-PCR, and by flow cytometry methods, respectively. RESULTS: The results showed moderate inflammation affecting the colon mucosa and submucosa, with significant changes in the number of lymphocytes in the colon tissue, elevated cytokines and eicosanoid levels, as well as disruption of the main cytokine and chemokine cell signaling pathways in colitis rats. Beta-glucans supplementation caused a reverse in the percentage of lymphocytes with stronger effects of ßGh and reduction of the levels of the inflammatory markers, and improvement of cytokine and chemokine signaling pathways with stronger effects of ßGl supplementation. CONCLUSIONS: The results indicate the therapeutic effect of dietary oat beta-glucan supplementation in the colitis in evident relation to the molecular weight of polymer.

Hepato- and gastro- protective activity of purified oat 1-3, 1-4-ß-d-glucans of different molecular weight.

Protective and antioxidant properties of highly purified oat ß-glucans of high and low molecular weight in liver and stomach were evaluated. The novelty in approach was to determine whether dietary ß-glucans affect the parameters of oxidative stress directly in the stomach and indirectly in the liver, especially in inflammation states. Physicochemical properties e.g. viscoelastic was found as strictly dependent from molecular weight of oat ß-glucans hence its metabolic activity could also show dependence. Three groups of rats were fed control diet and diet supplemented with low and high molecular weights oat ß-glucans. Animals were divided into controls and individuals with experimentally induced intestinal inflammation. Most active in increasing of total antioxidant status was low molecular weight ß-glucan. High molecular weight ß-glucan supplementation inhibits lipid oxidation the most in LPS treated animals. The results obtained from experiment encourage for dietary intervention with oat ß-glucans for stomach and liver protection during existing enteritis.

Higher PUFA and n-3 PUFA, conjugated linoleic acid, α-tocopherol and iron, but lower iodine and selenium concentrations in organic milk: a systematic literature review and meta- and redundancy analyses.

Demand for organic milk is partially driven by consumer perceptions that it is more nutritious. However, there is still considerable uncertainty over whether the use of organic production standards affects milk quality. Here we report results of meta-analyses based on 170 published studies comparing the nutrient content of organic and conventional bovine milk. There were no significant differences in total SFA and MUFA concentrations between organic and conventional milk. However, concentrations of total PUFA and n-3 PUFA were significantly higher in organic milk, by an estimated 7 (95 % CI -1, 15) % and 56 (95 % CI 38, 74) %, respectively. Concentrations of α-linolenic acid (ALA), very long-chain n-3 fatty acids (EPA+DPA+DHA) and conjugated linoleic acid were also significantly higher in organic milk, by an 69 (95 % CI 53, 84) %, 57 (95 % CI 27, 87) % and 41 (95 % CI 14, 68) %, respectively. As there were no significant differences in total n-6 PUFA and linoleic acid (LA) concentrations, the n-6:n-3 and LA:ALA ratios were lower in organic milk, by an estimated 71 (95 % CI -122, -20) % and 93 (95 % CI -116, -70) %. It is concluded that organic bovine milk has a more desirable fatty acid composition than conventional milk. Meta-analyses also showed that organic milk has significantly higher α-tocopherol and Fe, but lower I and Se concentrations. Redundancy analysis of data from a large cross-European milk quality survey indicates that the higher grazing/conserved forage intakes in organic systems were the main reason for milk composition differences.

Ciprofloxacin and furagin in acute cystitis: comparison of early immune and microbiological results.

Furagin (a nitrofurantoin analogue) has the same efficacy in treating acute cystitis as ciprofloxacin, however the duration of therapy is longer. We established a hypothesis that therapy with ciprofloxacin results in faster resolution of mucosal inflammation in comparison with furagin. Rates of urinary secretion of immunoglobulins class A, M and G and interleukin-8 (IL-8) were evaluated before and after initiation of therapy in adult women presenting with acute cystitis confirmed by urine culture. Women were randomised into two groups receiving either ciprofloxacin 250mg twice a day for 3 days (n=13) or furagin 100mg three times a day for 7 days (n=14). Median lengths of follow-up were 4 days and 5 days in the ciprofloxacin and furagin groups, respectively. Treatment with ciprofloxacin resulted in faster eradication of pathogens. No bacteria or nitrates were detected in the ciprofloxacin group, whilst leukocyte esterase was positive in only one case. In the furagin group there were four positive cultures, seven cases with positive nitrates and five cases with positive esterase. Secretion rates of all four substances dropped significantly, but the changes over time were similar in both groups.

[Hypercholesterolemic diets containing different common fats and rats plasma lipids]. / Diety hipercholesterolemiczne zawierajace rózne tluszcze spozywcze a lipidogram osocza szczurów.

The aim of the study was evaluated high-fat (20% w/w), hypercholesterolemic (3% w/w) diets differing in dietary fat type (butter, margarine with stanols, margarine with rapeseed oil and sunflower oil) influence on plasma lipids profile in male Wistar rats. The results show that cholesterol enriched diets, excluding diet containing margarine with stanols, had hypercholesterolemic effects on rats.

Effects of high-fat diets on body composition, hypothalamus NPY, and plasma leptin and corticosterone levels in rats.

We investigated the adipogenic effects of high-fat diets with different fat sources, as well as their influence on hypothalamus NPY content (NPY) and plasma corticosterone (Cs) and leptin (Lep) concentrations. In a 6-wk experiment performed in 28 male Wistar rats, high-fat diets (approx 60% of energy as fat) containing sunflower oil (S), rapeseed oil (R), palm oil (P), or lard (L) as the fat source were applied. Carcass composition was analyzed by standard methods; NPY, Cs, and Lep were determined by RIA method. Gas chromatography was applied to measure fatty acid composition of dietary fats. S group had the highest body fat content and Lep and the lowest Cs and NPY, while L rats had high Lep and the highest Cs and NPY. We conclude that the fatty acid composition of dietary fat is of high importance where effects of high fat diets on adiposity, as well as on plasma levels of both hormones and hypothalamus NPY content are concerned.

Influence of dietary fatty acids composition, level of dietary fat and feeding period on some parameters of androgen metabolism in male rats.

The aim of the present study was to determine the effect of the composition of dietary fatty acids, the duration of feeding period and dietary fat level on androgen metabolism in male rats. One hundred and twelve Wistar rats were divided into 18 groups which were fed three diets containing different types of fat (rapeseed [R], palm [P] and fish [F] oil) at either normal fat level (w/w; 5%) or high fat level (20%) during one, three or six weeks. Blood plasma level of androgen (testosterone+dihydrotestosterone) and testicular activity of 17beta-hydroxysteroid dehydrogenase (17beta-HSD) were investigated. In addition, androgen content in cytosol of the heart, the target organ, was measured. Androgen concentration in both blood plasma and heart cytosol extracts was measured by radioimmunoassay. The activity of 17Beta-HSD was expressed as a conversion of [3H]androstendione to [3H]testosterone in soluble fraction of gonadal homogenates. Plasma androgen concentration was influenced by a type of dietary fat (p<0.05). The highest plasma level of androgen was observed in animals fed R diets rich in unsaturated fatty acids. Significantly lower androgen concentration was demonstrated in rats fed P diets rich in saturated fatty acids. Only the feeding period factor significantly influenced androgen content in cytosol fraction of heart muscle cells (p<0.01). A positive correlation was found between plasma androgen concentration in plasma and cytosol fraction of the heart muscle cells (r=0.63, p<0.001). The feeding period (p<0.001) and dietary fat type (p<0.05) significantly affected the activity of 17beta-HSD. The least 17beta-HSD activity was observed in animals consuming the P-20% diet for six weeks. In summary, dietary fat type and feeding period, but not fat level, significantly affected both testosterone production and testosterone uptake by the target organ in male rats. It was found that a rapeseed diet rich in unsaturated fatty acids stimulated the testicular function in rats.