Effects Of Dietary Nucleotides Research Articles

Effects of dietary nucleotides on performance, proximate composition, health status, nitrogen stress resistance, and return on investment for Pacific white shrimp, Penaeus vannamei, raised in an intensive synbiotic system

Effects of dietary nucleotides on performance, proximate composition, health status, nitrogen stress resistance, and return on investment for Pacific white shrimp, Penaeus vannamei, raised in an intensive synbiotic system

Effects of dietary nucleotides and cationic peptides on vaccination response in cats

Modulation of the immune system through nutrition is the aim of many studies. As the induction of a rapid onset of immunity in cats is often critical, the objective of this study was to evaluate the effects of orally administered dietary nucleotides and cationic peptides, on the vaccination response in cats. The cats were allocated to two groups: Group A (n = 8) was fed a diet with dietary nucleotides and cationic peptides for ninety-two days, and Group C (n = 8) was fed a diet without the nucleotides and cationic peptides. The cats were vaccinated against feline herpesvirus 1 (FHV-1), feline calicivirus (FCV) and feline panleukopenia virus (FPV). The proliferation activity of lymphocytes and antibody response after vaccination were evaluated using ELISA kits. Comparing the two groups, a significant increase in the proliferation activity of the lymphocytes (P < 0.01) was observed in Group A, as well as a significant increase in the antibody titres after vaccination against feline herpesvirus (P < 0.05; P < 0.001), feline calicivirus (P < 0.01; P < 0.001) and feline panleukopenia virus (P < 0.01; P < 0.001). Protective levels of the antibodies were reached significantly earlier in Group A than in Group C. In conclusion, dietary nucleotides and cationic peptides have a positive effect on the lymphocyte proliferation and antibody production after vaccination against FHV-1, FCV and FPV in cats. Therefore, we assume that they can be used as a suitable immunostimulatory substance in feline practice.

Effects of dietary nucleotides on growth, survival and metabolic response in whiteleg shrimp, Litopenaeus vannamei against ammonia stress condition

This trial was conducted to evaluate the effects of nucleotides on growth of whiteleg shrimp, Litopenaeus vannamei, and the survival and metabolic responses to ammonia stress test. Experimental diets were as follows: low fish meal diet (LFMD), and four LFMD test diets, each supplemented with 0.1% guanosine monophosphate (GMP), 0.1% inosine monophosphate (IMP), 0.1% mixture of GMP and IMP and 0.1% mixture of GMP, IMP, uridine monophosphate (UMP) and cytidine monophosphate (CMP). The shrimp specimens (initial body weight: 0.99 ± 0.01 g) were randomly allocated into five groups and fed four times daily for 8-weeks. After the trial, final body weight was recorded and haemolymph was withdrawn for haematological analysis. The shrimp was then challenged with 70 mg/L ammonia (LC50) for 10 days. Survival and haemolymph of the shrimp were taken after exposure to ammonia. The highest growth performance was observed in the shrimp fed diet supplemented with GMP (p < .05), while survival was not influenced by the test diets in the feeding trial. In the ammonia challenge test, the highest survival was observed in the shrimp fed GMP supplemented diet compared to others. The plasma protein, glucose and cholesterol levels increased in all the treatments while triglycerides level decreased post challenge. Cortisol level recovered at day 10th after the challenge. Shrimps fed with nucleotides diets showed higher protein and glucose level compared to control groups post challenge. In general, nucleotides supplemented in the diet enhanced growth, improved stress resistance while modulating the haemolymph metabolites in L. vannamei under ammonia stress.

Bioaccumulation of water-borne silver nanoparticles and silver nitrate in striped catfish, Pangasianodon hypophthalmus, fed dietary nucleotides

Recent development in the nanotechnology industry and increase in the number of products manufactured by nanoparticles has inevitably contributed to the discharging of nanomaterials into the aquatic ecosystems. To improve the harmful effects of these toxic materials diverse complements like dietary nucleotides (NT) have been proposed. The effects of dietary NT on silver bioaccumulation in gill and muscle tissues were described after exposure to various concentrations of water-borne silver nanoparticles (AgNPs) and/or silver nitrate (AgNO3) in the present investigation. Specimens of striped catfish, Pangasianodon hypophthalmus , were divided into two groups fed with two different diets (control and NTsupplemented 0.75%) over a period of 10 weeks and were subsequently exposed to various concentrations of AgNPs and AgNO3 under static-renewal conditions for 10 days as follow: 1μg/L AgNPs, 1μg/L AgNO3, 20μg/L AgNPs and 20μg/L AgNO3. After the exposure period, samples of gill and muscle tissue were taken to measure silver bioaccumulation via atomic absorption spectrometry. Silver bioaccumulation in gills was about 5-10 times higher than those measured in the muscles. By increasing silver concentrations in the water, its accumulation in the tissues increased significantly. Generally, AgNO3tended to accumulate more than AgNPs in both tissues and all used concentrations. Fish fed on dietary NT showed lower silver accumulation levels in both tissues; although, the lower accumulation was more clear in gills in comparison to the muscles. It could be concluded that adding NT to the diet of striped catfish could significantly boost the fish defense against silver accumulation, but it is recommended to do some detailed studies to find out its mechanism.

Effects of Dietary Nucleotides on Immune Mechanisms and Physical State in Children with Chronic Respiratory Problems

Heavy industrial pollution and/or passive smoking negatively affect the overall immune health of a population. We used a model of children with chronic respiratory problems and evaluated the effects of short term supplementation of their diet with nucleotides. We measured the level of sIgA, eNO levels and total physical activity. We found positive effects of oral supplementation with commercially available nucleotides. Our data demonstrate strong improvements in physical activity, strong decrease of eNO levels and maintaining of the levels of sIgA. We conclude that supplementation with nucleotides offers an easy way to improve health conditions in children.

Effects of dietary nucleotides on growth performance, intestinal mor-phology and anti-oxidative activities of juvenile Litopenaeus vannamei

There has been extensive research into the role of nucleotides and their related metabolic products in aquatic feeds.Nucleotides and metabolites play key roles in many biological processes and are considered condi-tionally essential nutrients.During periods of rapid growth or certain disease states,dietary nucleotides may spare the cost of de novo nucleotides synthesis and optimize the function of rapidly dividing tissues,such as those in the gastrointestinal and immune systems.Research on dietary nucleotides in aquatic animals has illustrated that they may improve diet palatability,enhance growth in early stages of development,and maintain intestinal and liver health,as well as increase immunity and disease resistance.Despite their apparent importance,little is known about the benefits of supplementary nucleotides in Litopenaeus vannamei.We evaluated the effects of dietary nu-cleotides on growth,body composition,midgut morphology,and anti-oxidant activity in the hepatopancreas and serum in juvenile L.vannamei.We randomly assigned 960 shrimp(mean body weight: 1.01 g±0.02 g) into 8 trip-licate groups.Group G0(control) was fed a base diet and the remaining seven groups(G0.1,G0.2,G0.4,G0.6,G0.8,G1.0,and G1.2) were fed the base diet supplemented with 0.1,0.2,0.4,0.6,0.8,1.0,or 1.2 g/kg,respec-tively,of a nucleotide mixture containing adenosine-5′-monophosphate(AMP),cytidine-5′-monophosphate(CMP),uridine-5′-monophosphate disodium salt(UMP),inosine-5′-monophosphate disodium salt(IMP),and guanosine-5′-monophosphate disodium salt(GMP)(1 : 1 : 1 : 1 : 1 w/w,mix-NT).All groups were fed their re-spective diets three times a day(8:00,15:00,and 20:00) at the same fixed rate,which ranged from 4% to 6% of body weight,for 7 weeks.Specific growth rate(SGR) and survival(SR) tended to increase as the concentration of the dietary mix-NT increased,peaking in the group supplemented with 0.6 g/kg,though the differences among the groups were not significant(P0.05).The feed conversion rate(FCR) was lower in the treatment groups than in the control group,but not significantly(P0.05).The whole body moisture content was significantly affected by the level of dietary mix-NT supplementation(P0.05),but there were no significant differences in the content of crude protein,ether extract,or ash(P0.05).The dietary mix-NT had a significant effect on the hepatosomatic index(HSI) in the group supplemented with 0.6 g/kg(P0.05).Glutamic-oxaloacetic transaminease(GOT),glu-tamic-pyruvic transaminase(GPT),and uric acid(UA) content were significantly lower in shrimp fed 0.4 g/kg mix-NT(P0.05).There was a significant increase in the midgut jejunum wall thickness in shrimp fed 0.1–0.8 g/kg mix-NT,but there no significant difference in villus height of all groups.Alkaline phosphatase(AKP) activity and total antioxidant capacity(T-AOC) in the hepatopancreas tended to increase as the level of supplementation with dietary mix-NT increased,and were significantly higher in groups G0.2 and G0.4,respectively,than in the control(P0.05).Adding mix-NT had no significant effect on serum alkaline phosphatase(AKP) and superoxide dismutase(SOD) activity(P0.05).In conclusion,supplementing the diet with a mixture of 5 nucleotides im-proves hepatopancreas function,maintains intestinal morphology,and enhances anti-oxidant activity in the hepa-topancreas of juvenile L.vannamei.It would be interesting to determine the effects of nucleotide supplementation on immune function,particularly with respect to white spot syndrome virus(WSSV).

Effects of dietary nucleotides on acute stress response and cannabinoid receptor 1 mRNAs in sole, Solea solea

The objective of the present study was to evaluate the modulation of acute stress response by dietary nucleotides (NT) in sole, Solea solea. A basal diet was supplemented with levels of 0 (normal diet), or 0.4g NT/kg dry diet for 8weeks. At the end of feeding trial, fish fed the normal and NT-supplemented diet were subjected to a standardized protocol of disturbance and sampled over a 24h recovery after the stressor exposure. Modulatory effects of NT on acute stress response (cortisol and glucose), proopiomelanocortin (POMC) and cannabinoid receptor 1 splice variants (CB1A and CB1B) mRNA levels were studied. Both plasma cortisol and glucose levels of fish fed NT-supplemented diet were significantly lower than fish fed the control diet at 1 and 4h post-stress time-points. There are no significant effects of dietary NT on POMC and HSP70 mRNA levels. In our study, both CB1A and CB1B trascript levels were induced in fish fed the normal diet at 1 and 4h post-stress intervals. Collectively, the results obtained suggest that dietary NT modulates the CB1-like receptor mRNA expressions leading to attenuation in stressor-induced plasma cortisol level in sole.

Effects of Dietary Nucleotides on the Immune Response and Growth of Juvenile Pacific White Shrimp Litopenaeus vannamei (Boone, 1931)

Effects of dietary supplementation of nucleotides on immune response, survival against white spot syndrome virus (WSSV) challenge infection and growth of Pacific white shrimp Litopenaeus vannamei (Boone, 1931) juveniles were evaluated. The basal diet for Pacific white shrimp supplemented with nucleotide formula (Vannagen; Chemoforma, Augst, Switzerland) at 0%, 0.2%, 0.4% and 0.6% kg of feed were tested. Survival of shrimp was in the range of 92-97% and was not significantly different among treatments. However, specific growth rate (SGR), feed conversion efficiency (FCE) and protein productive value (PPV) were significantly better in shrimps fed the nucleotide-supplemented diet than those fed the control diet after a 60-day feeding trial. Survival of test animals upon challenge with WSSV infection was significantly higher in the nucleotide group than in the control group. Immune response indices i.e. total haemocyte count (THC), respiratory burst activity and phenoloxidase activity were significantly enhanced in shrimp fed diets containing nucleotides as compared to those fed diets with no supplementation. At the levels tested, 0.2% nucleotide in the diet was the optimum. These results indicate that dietary supplementation of nucleotides resulted in beneficial effects in improving growth, feed utilisation, protein utilisation and accelerate shrimp immune response against WSSV infection.

The role of dietary nucleotides in single-stomached animals

The transition from liquid to solid feed during weaning results in morphological, histological and microbial changes in the young animal's intestinal tract and often is associated with diarrhoea. The ban of in-feed antibiotics in pig production in the European Union has led to increasing interest in alternatives to overcome weaning-associated problems. Among others, nucleotides may have the potential to alleviate health impairments due to weaning. Nucleotides are natural components of the non-protein fraction of milk and have important effects on the maintenance of health in young animals. Nucleotides and their related metabolic products play key roles in many biological processes and become essential dietary components when endogenous supply is insufficient for normal function. The present review summarises nucleotide composition of milk from different species, the biology of nucleotides and possible effects of dietary nucleotides on intestinal morphology and function, intestinal microbiota, immune function, nutrient metabolism, hepatic morphology and function as well as growth performance. Special attention is given to data available for pigs, and suggestions are made for inclusion of nucleotides in the diet to benefit piglets' health and reduce the consequences accompanying early weaning.

Dietary Nucleotide Supplements in Infant Formula Modify the Expression of P-glycoprotein in the Intestinal Epithelium in vitro

The effect of dietary nucleotides at concentrations found in supplemented infant formula on P-glycoprotein (P-gp) expression in colon cells was examined. We report that P-gp expression in colon cells was significantly decreased in a time- and concentration-dependent manner. When colon cells were co-cultured with lymphocytes, so as to mimic the involvement of gut-associated lymphoid tissue in normal gut pathophysiology, we observed a reversal of this effect with a demonstrated increase in P-gp expression. These findings have important implications on effects of nucleotide exposure on increasing drug bioavailability, reducing the capacity for xenobiotic efflux, and increasing the risk of inflammatory bowel disease in susceptible infants. Future studies are directed at defining both the mechanisms underlying these findings and effects of dietary nucleotide supplementation in vivo.

Dietary nucleotides protect thymocyte DNA from damage induced by cyclophosphamide in mice

The effects of dietary nucleotides on thymocyte DNA damages induced by cyclophosphamide (CP) in mice were examined. First, phase I experiment was conducted to determine the optimal timing of detecting thymocyte DNA damages induced by CP (150 mg/kg body weight) in mice. Thymocyte DNA damages was determined at 6, 12, 18, 24 h by single-cell gel electrophosphoresis assay (comet assay) after intraperitoneal injection of CP. The levels of DNA damage at 6, 12, 18, 24 h were all significantly higher than that of the control group (p < 0.01). The highest level of DNA damage appeared at 18 h and then decreased at 24 h. Therefore, 18 h was selected to determine DNA damages induced by CP in subsequent experiments. In phase II experiment, 30 male KunMing mice were divided into three treatments: negative control (NC), positive control (PC) and nucleotides group (NG). Mice in NC and PC were fed nucleotide-free diet, and mice in NG were fed nucleotide-supplemented diet (supplemented with 0.25% nucleotides, a mixture containing equal amounts of AMP, CMP, GMP and UMP). Mice in PC and NG groups were injected with CP (150 mg/kg body weight) at 21 days. DNA damage in thymocytes was evaluated at 18 h after CP treatment. The results indicate that dietary nucleotides do not affect the weights of the thymus and the spleen, or their organ indices (p > 0.05), but significantly decrease the percentage of comet cells and comet tail sizes (p < 0.01). This study demonstrates that dietary nucleotides could reduce the level of thymocyte DNA damage induced by CP in mice.

Effects of Dietary Nucleotides on Immune Responses

In this study, the effects of dietary nucleotides on the immune response balance between T helper cells type 1 (Th1) and type 2, and on the mucosal immune response in weanling mice were investigated. It was demonstrated that dietary nucleotides up-regulate the Th1 immune response and suppress the antigen-specific IgE antibody response in weanling mice. Thus, the results suggest that dietary nucleotides may be beneficial for the prevention of allergic diseases in early infancy. In addition, it was shown that dietary nucleotides increased the proportion of a γδT-cell receptor (TCR) -bearing intestinal intraepithelial lymphocyte (IEL) subset, IL-7 production by intestinal epithelial cells and the antigen-specific IgA response. Therefore, the present study indicates that dietary nucleotides may have an effect on the mucosal intranet in the intestinal mucosal immune system.

Effects of Dietary Nucleotides on Immune Responses

Effects of Dietary Nucleotides on Immune Responses

The effects of dietary nucleotides on intestinal blood flow in preterm infants.

Nucleotides (NT) are reported to affect development of the immune and gastrointestinal systems, and they are currently added to most term infant formulas. In the present study, dietary NT effects on superior mesenteric artery blood flow were investigated. Formula-fed preterm infants were studied once with a 20 kcal/oz. term infant formula containing 80.6 mg/L of NT (NT+), and once with the same formula with no added NT (NT-) (n = 20, gestational age 28.0 +/- 2.2 wk). A reference group of preterm infants fed human milk was also studied (n = 20, gestational age 29.0 +/- 1.6 wk). Superior mesenteric artery blood flow velocities (BFV) were measured by Doppler ultrasound 15 min before and 30, 60, and 90 min after the start of the feed. BFV rose in all infants from baseline to 30 min after feed initiation, and progressively declined thereafter in infants fed NT- or human milk. However, NT+ feedings were associated with a minimal change in BFV between 60 and 90 min. As a result, the difference in blood flow velocities between baseline and 90 min was significantly greater with the NT+ versus the NT- feedings for the mean, peak systolic, and end diastolic velocities (p = 0.03, 0.05, and 0.03, respectively). BFV after the NT- and human milk feedings were similar. These data suggest that orally administered NT are associated with effects on the intestinal vasculature.

The Effects of Dietary Nucleotides on Intestinal Blood Flow in Preterm Infants

Nucleotides (NT) are reported to affect development of the immune and gastrointestinal systems, and they are currently added to most term infant formulas. In the present study, dietary NT effects on superior mesenteric artery blood flow were investigated. Formula-fed preterm infants were studied once with a 20 kcal/oz. term infant formula containing 80.6 mg/L of NT (NT+), and once with the same formula with no added NT (NT−) (n = 20, gestational age 28.0 ± 2.2 wk). A reference group of preterm infants fed human milk was also studied (n = 20, gestational age 29.0 ± 1.6 wk). Superior mesenteric artery blood flow velocities (BFV) were measured by Doppler ultrasound 15 min before and 30, 60, and 90 min after the start of the feed. BFV rose in all infants from baseline to 30 min after feed initiation, and progressively declined thereafter in infants fed NT− or human milk. However, NT+ feedings were associated with a minimal change in BFV between 60 and 90 min. As a result, the difference in blood flow velocities between baseline and 90 min was significantly greater with the NT+versus the NT− feedings for the mean, peak systolic, and end diastolic velocities (p = 0.03, 0.05, and 0.03, respectively). BFV after the NT− and human milk feedings were similar. These data suggest that orally administered NT are associated with effects on the intestinal vasculature.

Gene Expression in the Intestine: The Effect of Dietary Nucleotides

Gene Expression in the Intestine: The Effect of Dietary Nucleotides

Dietary nucleotides affect hepatic growth and composition in the weanling mouse.

The effect of dietary nucleotides upon hepatic growth and composition was examined in weanling mice. For 5 weeks, mice were fed either Purina Rat Chow, a nucleotide-free diet (NT-), a nucleotide-free diet supplemented with a mixture of five nucleotides (0.21% w/w), (NT+) or a nucleotide-free diet supplemented with adenosine 5'-monophosphate (0.0425% w/w) (NTA). Hepatic cholesterol and lipid phosphorous were significantly higher, whereas liver weight (expressed as a percentage of body weight), and glycogen were lower in animals fed NT- vs all other groups. NTA-fed animals presented a greater contrast to the NT- group than did animals fed the mixture of nucleotides. Liver fatty acid composition and distribution of phospholipid subclasses were not affected by dietary nucleotide supplementation. Dietary nucleotide supplementation in weanling mice affects hepatic growth and composition; adenosine 5'-monophosphate may play a unique role in these effects.

Effect of dietary nucleotides on the fatty acid composition of rat liver microsomes.

The present study was designed to evaluate the influence of dietary nucleotides on the lipid composition of liver microsomes in weanling rats. Rats at weaning were fed, one group with a semipurified nucleotide-free diet and three groups with the same diet supplemented with three different levels of each of the nucleotides AMP, GMP, IMP, UMP and CMP, during 4 weeks. Long chain polyunsaturated fatty acids of the n-6 and n-3 series were increased in phospholipids of liver microsomes for rats fed the nucleotide supplemented diets; however, the cholesterol/phospholipid phosphorus ratio was maintained fairly constant. The results obtained suggest that dietary nucleotides modify the polyunsaturated fatty acid metabolism through a lower rat liver delta-9 desaturase activity and through increased activities of delta-5 and delta-4 desaturases.

Effect of dietary nucleotides and orotate on the blood levels of prostacyclin (PGI 2) and thromboxane (TXA 2) in the weanling rat

Dietary nucleotides affect the maintenance of immune responses, tissue repair and polyunsaturated fatty acid metabolism. Orotate, a pyrimidine nucleotide precursor, induces fatty livers by impairing VLDL hepatic secretion. The aim of this study was to evaluate the changes in the blood levels of fatty acids and prostacyclin (PGI 2) and thromboxane (TXA 2) in the weanling rat caused by the dietary intake of nucleotides and orotate. Three groups of rats at weaning were fed a control diet, an orotate supplemented diet (O-50) and a nucleotide supplemented diet (N-50) during 4 weeks, respectively. Absolute values of plasma polyunsaturated fatty acids greater than 18 carbon atoms of the n-6 and n-3 series were increased in the N-50 group and decreased in O-50 with regard to the control. However, the relative fatty acid composition of plasma lipid fractions was mostly unaffected. Plasma 6-keto-PGF 1α showed a trend to be increased in N-50 and serum TXB 2 was significantly increased in that group. Both eicosanoids were unchanged by dietary orotate intake. These results may be explained because of the increased plasma 20:4n-6 found in rats fed a supplemented nucleotide diet. Thus, nucleotides present in foods appear to modulate PUFA conversion and eicosanoids synthesis in early life.

Effect of Dietary Nucleotides on Intestinal Repair in Rats with Experimental Chronic Diarrhea

Nucleic acid synthesis in tissues of rapid growth is preferentially done using dietary purines and pyrimidines via the salvage pathway. In the case of a low protein intake, dietary nucleotides may be semiessential for cell replication of gut, lymphocytes, and bone marrow, and especially in those intestinal diseases in which the mucosa is altered, dietary nucleotides may have a role in intestinal development. The effect of dietary nucleotides on intestinal weight and length, gut mucosal weight, intestinal protein and DNA contents, and lactase, maltase, and intestinal mucosal activities was assessed in a controlled way. Weanling (21-day-old) rats were separated into two groups of 36, each receiving blindly a basal diet containing glucose polymers (C) or a basal diet with lactose as the main carbohydrate (L) for 15 days. Those fed with L developed a syndrome of chronic diarrhea and malnutrition. Ten rats of each group were sacrificed at that time. The rest of the animals of each group were separated into two subgroups. The first was fed with the C diet and the second with the C diet supplemented with 50 mg/100 g of each of the following nucleotides: AMP, GMP, CMP, UMP, and IMP (CN). Thus the subgroups CC, CN, LC, and LN were formed. Rats were sacrificed after 4 weeks and gut separated into three segments corresponding to duodenum, jejunum, and ileum. Analysis of variance was used to compare the effect of diet or segments. DNA and lactase, maltase, and sucrase activities increased in the LN group with respect to LC especially in jejunum and ileum but there were not any differences between CC and CN.(ABSTRACT TRUNCATED AT 250 WORDS)