Miro Smriga

University of Georgia, Athens, GA, United States

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Publications (31)92.1 Total impact

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    ABSTRACT: Lysine affects diarrhea and anxiety via effects on serotonin receptors, enhanced intestinal repair, and sodium chloride-dependent opioid peptide transport. The objective was to investigate the effects of lysine supplementation on morbidity, growth, and anxiety in children and adults of peri-urban areas of Accra, Ghana. In a double-blind randomized trial, the effect of lysine supplementation (1 g lysine/d) compared with that of placebo was examined in 2 groups of men, women, and children (n = 271). Primary outcomes included diarrheal and respiratory morbidity, growth, and anxiety and complement C3, C-reactive protein, serum cortisol, transferrin, and ferritin values. Independent-sample t tests, odds ratios, generalized estimating equations, 4-parameter sinusoid regression, and generalized linear models were used. Thirty percent of men, 50% of women, and 15% of children were at risk of lysine inadequacy. Supplementation in children reduced diarrheal episodes [19 lysine, 35 placebo; odds ratio (OR): 0.52; 95% CI: 0.29, 0.92; P = 0.046] and the total number of days ill (21 lysine, 47 placebo; OR: 0.44; 95% CI: 0.26, 0.74; P = 0.034). Mean days ill per child per week (0.058 ± 0.039 lysine, 0.132 ± 0.063 placebo; P = 0.017) were negatively associated with weight gain with control for baseline weight and study group (P = 0.04). Men had fewer coryza episodes (23 lysine, 39 placebo; OR: 0.60; 95% CI: 0.36, 1.01; P = 0.05), total number of days ill (lysine: 130; placebo: 266; OR: 0.51; 95% CI: 0.28, 0.93; P = 0.03), and mean days ill per person per week (lysine: 0.21 ± 0.23; placebo: 0.41 ± 0.35; P = 0.04). Serum ferritin (P = 0.045) and C-reactive protein (P = 0.018) decreased in lysine-supplemented women but increased in placebo-supplemented women. Lysine supplementation reduced diarrheal morbidity in children and respiratory morbidity in men in Ghana.
    American Journal of Clinical Nutrition 10/2010; 92(4):928-39. · 6.50 Impact Factor
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    ABSTRACT: Savory (umami) condiments are widely used throughout the world to enhance taste properties of some foods. Archeological research has indicated that the use of such condiments, notably high quality fish sauces (garum), might have been extensive already in the ancient Roman Empire; however, little is known about the biochemical composition of garum. The aim of this study was to sample remnants of garum from preserved containers (dolia) located in Pompeii, evaluate concentrations of free amino acids, and compare them to those of modern fish sauces produced in southern Italy and southeast Asia. In spite of significant degradation of amino acids, analysis of remnants from ancient garum confirmed a pattern of free amino acids that was comparable to the pattern detected in modern Italian and Asian products, with free glutamate being the taste-dominant amino acid, followed by sweet-tasting glycine and alanine. Since the above free amino acids are the determining taste substances in savory sauces, the present finding indicates that Romans in the first century AD enjoyed umami condiments with taste profiles paralleling those of modern Asian fish sauces. If technology transfers from Europe to Asia could be documented by archeological means, this study would be the first indication of an early “globalization” in food taste preferences.
    Journal of Food Composition and Analysis 08/2010; · 2.09 Impact Factor
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    ABSTRACT: Previous studies have shown an effect of lysine fortification on nutrition and immunity of poor men, women, and children consuming a predominantly wheat-based diet. To examine the lysine value of diets and the effect of lysine fortification on functional protein status, anthropometry, and morbidity of men, women, and children in rural Syria. At baseline of a two-phase study using 7-day household food intake inventories (n = 98), nutrient availabilities per adult male equivalent were estimated. In the intervention phase, a 16-week double-blind trial, households (n = 106) were randomly assigned to control and lysine groups. Hematologic and anthropometric data were collected from men (n = 69; 31 control, 38 lysine), women (n = 99; 51 control, 48 lysine), and children (n = 69; 37 control, 32 lysine) at baseline, 12 weeks, and 16 weeks. Total CD3 T lymphocytes as well as T lymphocytes bearing the receptors CD4, CD8, and CD56, IgM, IgG, IgA, complement C3, C-reactive protein, serum albumin, prealbumin, transferrin, retinol-binding protein, hemoglobin, and hepatitis B surface antigen were determined. Health status and flour usage were monitored. Paired- and independent-sample t-tests and chi-square tests were performed. Mean nutrient availability per adult equivalent was 2,650 +/- 806 kcal, 70.1 +/- 26.4 g protein, 65 +/- 14% cereal protein, and 41.9 +/- 0.8 mg lysine per gram of protein. Complement C3 was significantly higher in men receiving lysine than in controls (p < .05). Among women, there were significant differences between the control and lysine groups in diarrhea period prevalence (total number of diarrheal episodes during the period of intervention divided by the total number of observations), (20 in the control group, 6 in the lysine group; p = .014), the mean number of days ill (0.4 +/- 0.7, control, 0.14 +/- 0.4, lysine, p = 0.03), and the number of diarrheal episodes per person per year (1.39 in the control group, 0.47 in the lysine group). No other significant differences between the lysine and the control groups were observed. Lysine fortification of wheat flour demonstrated a positive effect on diarrheal morbidity in women. The effect could be attributed to an improvement in protein utilization but possibly also to a direct effect of lysine in gastrointestinal tract. Studies in populations with higher diarrheal prevalence and significant dietary lysine deficiency are needed to determine whether the reported effects on diarrheal prevalence are replicable and whether they are pharmacological or nutritional. It would be particularly desirable to study the effect of lysine on diarrhea in preschool children, who have much higher morbidity and mortality rates from this disease than school-age children or adults.
    Food and nutrition bulletin 09/2008; 29(3):163-71. · 2.11 Impact Factor
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    ABSTRACT: Dietary supplementation with an essential amino acid L-lysine has been shown to reduce chronic anxiety in humans with low dietary intake of L-lysine. A combination of L-lysine and L-arginine has been documented to normalize hormonal stress responses in humans with high trait anxiety. The present study was carried out in one hundred eight healthy Japanese adults. The aim of study was to find out whether a week-long oral treatment with L-lysine (2.64 g per day) and L-arginine (2.64 g per day) reduces trait and stress-induced state anxiety and basal levels of stress hormones. We confirmed that, without regard to gender, the amino acid treatment significantly reduced both trait anxiety and state anxiety induced by cognitive stress battery. In addition, we found that the treatment with L-lysine and L-arginine decreased the basal levels of salivary cortisol and chromogranin-A (a salivary marker of the sympatho-adrenal system) in male subjects. These results of this double-blind, placebo controlled and randomized study confirm the previous findings in humans and animals and point to a combination of L-lysine and L-arginine as a potentially useful dietary intervention in otherwise healthy humans with high subjective levels of mental stress and anxiety.
    Biomedical Research 05/2007; 28(2):85-90. · 1.26 Impact Factor
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    ABSTRACT: In this article we discuss studies showing that rats are able to regulate their intake of BCAA depending on the level of exercise, and that they will choose a solution of BCAA over water during times of intense exercise. We found that the voluntary intake of a solution made of BCAA, L-arginine and L-glutamine positively correlated with the timing and volume of exercise during the dark (active) period of the circadian rhythm. In the second behavioral protocol in which rats were fed BCAA fortified diet (2.0%, wt:wt), we observed voluntarily increased volume of physical activity beginning from d 4 of feeding on. In the second, neuro-behavioral, part of the study we measured the brain content of 5-hydroxytryptamine (5-HT) as well as plasma amino acid profiles in well-trained exercising rats to test a hypothesis that BCAA may alleviate central aspects of fatigue. A solution made of BCAA, L-arginine, and L-glutamine applied before running elevated the BCAA/tryptophan plasma ratio at the end of and after running, and decreased 5-HT release in the lateral hypothalamus and amygdala after running, when compared with the controls. The exercise-related shift in the fluid preference toward a BCAA-based solution suggests an ergogenic benefit. The forced-running study shows the lateral hypothalamus and possibly amygdala might be the critical brain regions implied in the central effects of a BCAA-based solution.
    Journal of Nutrition 03/2006; 136(2):548S-552S. · 4.20 Impact Factor
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    ABSTRACT: The aim of the present study was to evaluate possible modulatory effect of the treatment with L-lysine and L-arginine on neuroendocrine activation during psychosocial stress in healthy subjects with relatively high trait anxiety in a randomized, double blind placebo controlled trial. In 29 healthy subjects at the upper limit of the normal range of a trait anxiety scale, a mixture of L-lysine and L-arginine (3 g each/day) was administered for 10 days followed by exposure to a psychosocial stress procedure based on public speech. Hormone levels, cardiovascular activation and skin conductance were measured. Amino acid treatment resulted in enhanced adrenocorticotropic hormone, cortisol, adrenaline and noradrenaline levels and galvanic skin responses during stress compared to those in placebo-treated group. Increases in the heart rate and blood pressure in response to public speaking task were not influenced by amino acid treatment. Results of the present study support the hypothesis that L-lysine in combination with L-arginine, which may induce anxiolytic effects, modify hormonal responses during psychosocial stress in humans. Such action may represent a normalization of hormone levels to the pattern observed previously in subjects with low trait anxiety.
    Nutritional Neuroscience 07/2005; 8(3):155-60. · 1.65 Impact Factor
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    Miro Smriga, Kunio Torii
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    ABSTRACT: Amino acids, like carbohydrates and fatty acids, are basic nutrients. Twenty amino acids furnish the minimal requirements for growth, nitrogen equilibrium, maintenance of host defenses, neural (Fernstrom, 2000; Young, El-Khoury, Melchor, & Castillo, 1994) and muscular functions, as well as gene-expression regulation (Fafournoux, Bruhat, & Jousse, 2000). The catabolism of amino acids provides an energy source via the intermediate products of the glycolytic pathways and the citric acid cycle. The human body is incapable of storing large amounts of amino acids, and their homeostasis must be finely maintained by the integrated action of all tissues and organs. For this reason, the dietary requirement for amino acids has important health consequences (Millward, 1994; Rose, 1957; Young, 1998; Young & Borongha, 2000). Nine amino acids are considered indispensable in the diet, but the demarcation between dispensability and indispensability is blurred by discoveries that have revealed effects of age (Baertl, Placko, & Graham, 1974; Schober, Kurz, Musil, & Jarosch, 1989), nutritional status (Kurpad et al., 2003), and psycho-behavioral conditions, such as exposure to severe stress (Lacey & Wilmore, 1990; Obled, Papet, & Breuille, 2002; Smriga & Torii, 2002).
    12/2004: pages 325-340;
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    ABSTRACT: L-leucine, an essential amino acid, is one of the most popular ingredients in dietary supplements. To investigate a possibility of its embryo-fetal toxicity in rats, 11- to 12-week old dams were orally administered an aqueous solution of L-leucine at doses of 300 or 1000 mg/kg body weight on gestational days 7-17. Body weight and feed intake was evaluated throughout the whole course of pregnancy (days 0-20). L-Leucine did not influence body weight, but at a dose of 1000 mg/kg, slightly enhanced feed intake on days 14 and 18 of pregnancy. Caesarean section (day 20) revealed no influences on the litter size and weight of live-born fetuses, the number of corpora lutea, implantation index or the quality of placenta, and the minor increase in feed intake was considered irrelevant to the pregnancy outcomes. Fetuses were evaluated in a battery of external, visceral and skeletal examinations. No effects of L-leucine on gender ratio and external abnormalities, and no significant treatment-related variations in visceral and skeletal pathologies were observed. These results suggested that L-leucine, administered orally during organogenesis at doses up to 1000 mg/kg body weight, did not affect the outcome of pregnancy and did not cause fetotoxicity in rats.
    Food and Chemical Toxicology 10/2004; 42(9):1505-11. · 3.01 Impact Factor
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    ABSTRACT: The effects of fortifying a diet with L-lysine HCl (Lys) and L-arginine (Arg) in broilers housed under conditions of high stock density, were studied in an experiment that measured bodyweight, feed intake, feed conversion, body temperature, serum protein, immune parameters and neutrophils. A diet fortified with Lys and Arg increased bodyweight gain in broilers housed under high stock density conditions, but not in normally housed controls. The diet fortified with Lys and Arg decreased the feed conversion ratio and abdominal fat, as compared to the effects of a control diet, without regard to housing conditions. No effects of amino acid fortification or stock density on body temperature, serum protein or immune parameters were recorded. The results indicate that an increase in the dietary supply of Lys and Arg is beneficial to broilers during stressful conditions of high stock density, potentially contributing to an enhancement of animal welfare in broiler farms.
    Animal Science Journal 07/2004; 75(4):339 - 343. · 1.04 Impact Factor
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    ABSTRACT: Lysine is a limiting amino acid in diets based on wheat as the staple. In experimental animals, prolonged dietary lysine inadequacy increases stress-induced anxiety. If observed in humans, such a result would have a strong implication for the relationship between nutrition and communal quality of life and mental health. As part of a 3-month randomized double-blind study, we tested whether lysine fortification of wheat reduces anxiety and stress response in family members in poor Syrian communities consuming wheat as a staple food. In the lysine-fortified group, the plasma cortisol response to the blood drawing as a cause of stress was reduced in females, as was sympathetic arousal in males as measured by skin conductance. Lysine fortification also significantly reduced chronic anxiety as measured by the trait anxiety inventory in males. These results suggest that some stress responses in economically weak populations consuming cereal-based diets can be improved with lysine fortification.
    Proceedings of the National Academy of Sciences 07/2004; 101(22):8285-8. · 9.81 Impact Factor
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    ABSTRACT: L-Lysine hydrochloride (Lys) is an essential amino acid in humans and animals, and it is used in animal feeds, in prevention of herpes simplex recurrence, and cereal fortification in some developing countries. This study evaluated toxicological and behavioral effects of Lys during a dosing study with male and female Sprague-Dawley rats. The amino acid was incorporated into a standard diet at doses equal to 1.25%, 2.5%, and 5.0% (w/w). A control group of rats received a standard diet. All diets were administered ad libitum for 13 consecutive weeks. To examine stability of any potential effects, the administration period was followed by a 5-week recovery period, during which only the standard diet was provided to all animals. In male and female rats in each concentration group, treatment-related changes were not observed in the clinical signs, body weights, diet consumption, water intake, ophthalmology, gross pathology, organ weights, or histology. A Lys-related drop in serum concentration and an increase in urine excretion of chlorides was a compensatory reaction to the ingested hydrochloride. No functional, biochemical, or histological changes in renal function were found. The no-observed-adverse-effect level (NOAEL) for Lys was estimated at 5.0% for both genders (male, 3.36 +/- 0.12 g/kg/day; female, 3.99 +/- 0.28 g/kg/day).
    International Journal of Toxicology 06/2004; 23(2):113-8. · 1.35 Impact Factor
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    ABSTRACT: The amino acid L-arginine (Arg) has been used extensively in dietary and pharmacological products. This study evaluated toxicological and behavioral effects of Arg produced by Ajinomoto Co. (Tokyo, Japan) during a dosing study with male and female Sprague-Dawley rats. The amino acid was incorporated into a standard diet at doses equal to 1.25%, 2.5%, and 5.0% (w/w). A control group of rats received only a standard diet. All diets were administered ad libitum for 13 continuous weeks. To examine recoverability of any potential effects, the administration period was followed by a 5-week-long recovery, during which only a standard diet was provided. In male and female rats in each concentration group, treatment-related changes were not observed for clinical signs, body weights, diet consumption, ophthalmology, gross pathology, organ weight, or histopathology. An elevated level of plasma glucose was detected in some male rats (5.0%, w/w) during the analysis conducted in the fifth week of administration; however, the degree of the change was within the physiological range, and no changes were observed at the end of the administration period. In the same group, an increase in hemoglobin, together with a tendency toward an increase in the red blood cell counts, was found, but the change was considered toxicologically insignificant. The no-observed-adverse-effect level (NOAEL) for Arg was estimated at 5.0% (w/w) for both genders (males, 3.3 +/- 0.1 g/kg/day; females, 3.9 +/- 0.2 g/kg/day).
    International Journal of Toxicology 06/2004; 23(2):101-5. · 1.35 Impact Factor
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    ABSTRACT: L-Glutamine (Gln) is a semiessential amino acid used in enteral feeding in critically ill patients, and is contained in numerous dietary supplements available to the general public. This study evaluated toxicological effects of Gln in male and female Sprague-Dawley rats. Gln produced by Ajinomoto Co. (Tokyo, Japan) was incorporated into a standard diet at doses equal to 1.25%, 2.5%, and 5.0% (w/w), respectively. A control group of rats received only a standard diet. All diets were administered ad libitum for 13 consecutive weeks. To examine recoverability of any potential effects, the administration period was followed by a 5-week recovery period, during which only the standard diet was provided to all animals. Throughout the administration and recovery periods, no deaths were observed, and no changes in diet consumption, ophthalmologic findings, gross pathology, and histopathology were detected. Several changes in urine parameters (total protein, urine pH, and a positive incidence (+/-) of ketone bodies) were observed in the 2.5% and 5.0% groups at the end of the administration period. Minor increases were found in hematology parameters for the 5.0% group (platelet count, gamma-globulin, lactate dehydrogenase [LDH]), but all changes were within physiological range. No effects of administration were observed in the 1.25% group. The no-observed-adverse-effect level (NOAEL) for Gln was estimated at 1.25% for both genders (males 0.83 +/- 0.01 g/kg/day; females, 0.96 +/- 0.06 g/kg/day).
    International Journal of Toxicology 06/2004; 23(2):107-12. · 1.35 Impact Factor
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    ABSTRACT: Branched-chain amino acids (L-isoleucine, L-valine, and L-leucine) are being increasingly used in sport supplements. This study evaluated toxicological and behavioral effects of L-isoleucine (Ile), L-valine (Val), and L-leucine (Leu) during a dosing study with male and female Sprague-Dawley rats. The amino acids were incorporated into a standard diet at doses equal to 1.25%, 2.5%, and 5.0% (w/w). A control group of rats received a standard diet. All diets were administered ad libitum for 13 consecutive weeks. To examine stability of any potential effects, the administration period was followed by a 5-week recovery period, during which only the standard diet was provided to all animals. No significant, dose-related effects on body weight were found in rats fed a Leu- and Ile-supplemented diet. Val mixed into a diet at 5.0% (w/w) decreased slightly, but significantly body weight gain in females, but not males. Ile (5.0% w/w) affected the urine electrolytes, protein, ketone bodies, urine glucose, and urobilinogen in both genders, yet the observed changes remained mostly within the range observed in controls. The random findings in hepatology and ophthalmology at the 13-week sacrifice were not considered toxicologically relevant to effects of the tested amino acids. No significant changes in organ weights were recorded. We estimate the no-observed-adverse-effect level (NOAEL) for Ile at 2.5% for both genders (male, 1.565 +/- 0.060 g/kg/day; females, 1.646 +/- 0.095 g/kg/day), Val at 5.0% for males (3.225 +/- 0.135 g/kg/day) and 2.5% for females (1.853 +/- 0.060 g/kg/day), and Leu at 5.0% for both genders (males, 3.333 +/- 0.101 g/kg/day: females, 3.835 +/- 0.257 g/kg/day).
    International Journal of Toxicology 06/2004; 23(2):119-26. · 1.35 Impact Factor
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    Miro Smriga, Kunio Torii
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    ABSTRACT: The purpose of this investigation was to determine whether a nutritionally essential amino acid, l-lysine, acts like a serotonin receptor 4 (5-HT4) antagonist, and if l-lysine is beneficial in animal models of serotonin (5-HT)-induced anxiety, diarrhea, ileum contractions, and tachycardia and in stress-induced fecal excretion. The radioligand-binding assay was used to test the binding of l-lysine to various 5-HT receptors. The effects of l-lysine on 5-HT-induced contractions of isolated guinea pig ileum were studied in vitro. The effects of oral administration of l-lysine on diarrhea, stress-induced fecal excretion, and 5-HT-induced corticosterone release, tachycardia, and anxiety (an elevated plus maze paradigm) were studied in rats in vivo. l-Lysine (0.8 mmol/dl) inhibited (9.17%) binding of 5-HT to the 5-HT4 receptor, without any effect on 5-HT1A,2A,2B,2C,3 binding. l-Lysine (0.07 and 0.7 mmol/dl) blocked 5-HT-induced contractions of an isolated guinea pig ileum in vitro (P < 0.05 and P < 0.01). Orally applied l-lysine (1 g/kg of body weight) inhibited (P < 0.12) diarrhea triggered by coadministration of restraint stress and 5-hydroxytryptophane (10 mg/kg of body weight), and significantly blocked anxiety induced by the 5-HT4 receptor agonist (3.0 mmol/liter) in rats in vivo. No effects of l-lysine or the 5-HT4 receptor agonist on plasma corticosterone and heart rate were recorded. l-Lysine may be a partial 5-HT4 receptor antagonist and suppresses 5-HT4 receptor-mediated intestinal pathologies and anxiety in rats. An increase in nutritional load of l-lysine might be a useful tool in treating stress-induced anxiety and 5-HT-related diarrhea-type intestinal dysfunctions.
    Proceedings of the National Academy of Sciences 01/2004; 100(26):15370-5. · 9.81 Impact Factor
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    ABSTRACT: We studied the effects of diet fortified with L-lysine HCl (Lys) and L-arginine (Arg) on stress (transportation) responses in male finishing pigs (Landrace x LargeWhite x Duroc). Pigs (n = 16) were randomly divided into two equally sized groups so that the average starting body weight in the groups was identical. For 1 week immediately preceding the transportation, the first group of pigs received a control diet while the second group received a Lys and Arg fortified diet. Plasma aminogram, cortisol and body weight were evaluated. Behavior of pigs was measured with the help of a video camera, recorded for 2 h at the same time, as on the day, before a day and immediately after transportation. The study revealed main stimulatory effects of transportation and main inhibitory effect of Lys and Arg on plasma cortisol (P < 0.05) without transportation x treatment interactions. Pigs fed with Lys and Arg diet tend to have higher body weight at the end of the experiment, when compared to their normally fed counterparts, but the difference did not reach a significant level (P < 0.21). Lys and Arg diet significantly inhibited stress-induced increase in locomotion (P < 0.05), without affecting feeding pattern. Transportation stress decreased plasma Lys and Arg. This decrease was reversed in the fortified group, and what is more the plasma Lys and Arg levels were significantly higher than in controls (P < 0.05). Lys and Arg enhanced plasma urea production (P < 0.05), without regards to stress. The behavioral results indicate a reduction in stress-induced anxiety in pigs fed with Lys and Arg fortified diet, that parallels similar observations in research with rats and broilers. The mechanism probably involves a decreased plasma cortisol, and/or normalized plasma Lys, Arg levels.
    Nutritional Neuroscience 10/2003; 6(5):283-9. · 1.65 Impact Factor
  • M Smriga, K Torii
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    ABSTRACT: We studied the effects of L-lysine on wrap-restraint stress-induced changes in ureagenesis. An exposure to wrap-restraint stress did not affect the plasma concentration of L-lysine, but did decrease plasma urea and arginine. Oral L-lysine (1 g/kg) blocked the effect of stress on ureagenesis, and enhanced the effect of stress on L-arginine. No influence of L-lysine were found in controls. The results imply a stress-specific, ureagenesis-stimulating effect of L-lysine, and suggest an increased requirement for L-arginine during the above conditions.
    Amino Acids 07/2003; 24(4):435-7. · 3.91 Impact Factor
  • Miro Smriga, Kunio Torii
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    ABSTRACT: The aim of this study was to investigate whether a chronic pretreatment with a combination of L-lysine (Lys) and L-arginine (Arg) reduces anxiogenic effects of acute stress in rats. Male rats were orally infused with a distilled water solution of L-glutamine (200 mg/kg), Lys (200 mg/kg), or a combination of Lys (200 mg/kg) plus Arg (200 mg/kg) for four consecutive days (twice daily) and subjected to restraint stress on the fifth day. Immediately thereafter, rats were placed on an elevated plus maze (EPM) and their behavior was evaluated for 10 min. Lys and Arg significantly increased exploration time rats spent on open arms of the EPM, as compared to L-glutamine controls. In addition, the combination of Lys and Arg partly, but significantly, decreased stress-enhanced plasma corticosterone measured at the end of behavioral testing. Data suggest that a treatment with a solution of Lys and Arg reduces anxiety in stressed rats.
    Nutritional Neuroscience 05/2003; 6(2):125-8. · 1.65 Impact Factor
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    ABSTRACT: Little is known about the psychobehavioral consequences of a dietary deficiency of the amino acid, L-lysine. This report demonstrates that a 4-d long L-lysine deficiency in rats interfered with the normal circadian release of the neurotransmitter serotonin, but not dopamine, measured by in vivo microdialysis in the central nucleus of the amygdala. L-Lysine deficiency was induced by feeding rats a L-lysine-deficient diet. Controls were pair-fed a L-lysine-sufficient diet. Footshock stress-induced anxiety, measured in an elevated plus-maze paradigm, and wrap-restraint stress-stimulated fecal excretion were significantly greater in the L-lysine-deficient rats than in the controls. We conclude that a severe deficiency of dietary L-lysine enhances serotonin release in the amygdala, with subsequent changes in psychobehavioral responses to stress.
    Journal of Nutrition 01/2003; 132(12):3744-6. · 4.20 Impact Factor
  • M Smriga, M Kameishi, K Torii
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    ABSTRACT: Taste acceptance involves both innate and acquired components. We observed an increased acceptance of salty and sweet solutions in adult rats whose tongues had been exposed to an NaCl-enriched milk formula during one day of early postnatal development. This behavioral effect was associated with changes in the norepinephrine system of the basolateral amygdala. No other changes in behavior, food intake, body weight, blood or metabolic parameters of the NaCl-exposed adult rats were identified. The data suggest a causal relationship between NaCl taste exposure, low content of amygdala norepinephrine cells and enhanced intake of sweet and salty compounds by adult rats. They also raise the question of the extent to which similar phenomena may occur during early human infant feeding.
    Neuroreport 01/2003; 13(18):2565-9. · 1.40 Impact Factor

Publication Stats

229 Citations
92.10 Total Impact Points

Institutions

  • 2010
    • University of Georgia
      • Department of Classics
      Athens, GA, United States
  • 2008–2010
    • The Nevin Scrimshaw International Nutrition Foundation
      Boston, Massachusetts, United States
  • 2003–2007
    • Ajinomoto-Genetika Research Institute
      Moskva, Moscow, Russia
  • 2006
    • Ajinomoto Group
      Edo, Tōkyō, Japan
  • 2000–2004
    • AJINOMOTO CO., INC.
      Edo, Tōkyō, Japan
  • 2000–2002
    • Daiwa House Central Research Laboratory
      Edo, Tōkyō, Japan
  • 1995–2001
    • The University of Tokyo
      • • Department of Pharmaceutical Sciences
      • • Faculty and Graduate School of Pharmaceutical Sciences
      Tokyo, Tokyo-to, Japan