Effects Of L-arginine Supplementation Research Articles

Effect of L-Arginine Supplementation in treatment of Intrauterine Fetal Growth Restriction

Effect of L-Arginine Supplementation in treatment of Intrauterine Fetal Growth Restriction

Aerobic exercise prevents cardiomyocyte damage caused by oxidative stress in early cardiovascular disease by increasing vascularity while L-arginine supplementation prevents it by increasing activation of the enzyme nitric oxide synthase.

L-Arginine and chronic exercise reduce oxidative stress. However, it is unclear how they affect cardiomyocytes during cardiovascular disease (CVD) development. The aim of this research was to investigate the possible effects of L-arginine supplementation and aerobic training on systemic oxidative stress and their consequences on cardiomyocytes during cardiometabolic disease onset caused by excess fructose. Wistar rats were allocated into four groups: control (C), fructose (F, 10% fructose in water), fructose training (FT; moderate running, 50-70% of the maximal velocity), and fructose arginine (FA; 880 mg/kg/day). Fructose was given for two weeks and fructose plus treatments for the subsequent eight weeks. Body composition, blood glucose, insulin, lipid profile, lipid peroxidation, nitrite, metalloproteinase-2 (MMP-2) activity, left ventricle histological changes, microRNA-126, -195, and -146, eNOS, p-eNOS, and TNF-α expressions were analyzed. Higher abdominal fat mass, triacylglycerol level, and insulin level were observed in the F group, and both treatments reversed these alterations. Myocardial vascularization was impaired in fructose-fed groups, except in FT. Cardiomyocyte hypertrophy was observed in all fructose-fed groups. TNF-α levels were higher in fructose-fed groups than in the C group, and p-eNOS levels were higher in the FA than in the C and F groups. Lipid peroxidation was higher in the F group than in the FT and C groups. During CVD onset, moderate aerobic exercise reduced lipid peroxidation, and both training and L-arginine prevented metabolic changes caused by excessive fructose. Myocardial vascularization was impaired by fructose, and cardiomyocyte hypertrophy appeared to be influenced by pro-inflammatory and oxidative environments.

The effect of L-arginine supplementation along with 6 weeks of Aquatic training on changes in blood pressure and fasting blood sugar in older peoples with Hypertension

The effect of L-arginine supplementation along with 6 weeks of Aquatic training on changes in blood pressure and fasting blood sugar in older peoples with Hypertension

One-Week L-Arginine Supplementation Had No Effect on 200m Freestyle Swimming Time Trial in Moderately-Trained Male Swimmers

Research on the effect of L-arginine supplementation on exercise performance is still inconsistent and its influence on single-bout swimming performance has not been investigated. Therefore, the aim of this study was to assess if one-week L-arginine supplementation would enhance 200-m freestyle swimming performance in trained/developmental (regularly training ∼3 times per week with a purpose to compete) male swimmers. In a randomized, cross-over, double-blind design, 8 trained/developmental male swimmers (age 25 ± 5 years; mean ± SD) completed 200-m freestyle swimming time-trial on 3 separate occasions: a control trial; and after 2 separate 7-d supplementation periods, with a daily dose of either 8 g/d of L-arginine or placebo trials. Blood lactate concentration was measured immediately post time-trial swimming. Completion time of the 200-m freestyle swimming time-trial did not differ significantly (F = 4.55; P = 0.060; ŋp2 = 0.394) between control (149.40 ± 9.88 s), L-arginine (146.02 ± 10.34 s) and placebo trials (147.58 ± 10.86 s). There was no statistically significant difference in post time-trial swimming blood lactate concentration between trials (control: 11.2 ± 2.7; L-arginine: 13.1 ± 1.8; Placebo: 12.2 ± 2.7, F = 3.52; P = 0.058; ŋp2 = 0.335). One-week of supplementation with 8 g/d of L-arginine, had no ergogenic effect on middle-distance (200-m), freestyle swimming performance in trained/developmental male swimmers.

L-arginine supplementation improved neonatal outcomes in pregnancies with hypertensive disorder or intrauterine growth restriction: A systematic review and meta-analysis of randomized controlled trials

Previous research established that the availability of l-arginine affects placental vascular development and fetal growth. However, practical details associated with the effects of l-arginine supplementation on the neonatal outcomes of hypertensive disorder (HD) and intrauterine growth restriction (IUGR) pregnancies are limited. The PubMed, ScienceDirect, and Web of Science databases were searched for peer-reviewed literature published by September 30, 2021 to investigate the operational details of l-arginine supplementation in improving neonatal outcomes in complicated pregnancies. Standardized mean difference (SMD) and weighted mean difference (WMD) of continuous variables, as well as the risk ratio (RR) for categorical variables were pooled by random-effects models. The results indicated that l-arginine supplementation increased the plasma nitric oxide (NO) concentrations in IUGR pregnancies (SMD: 0.71; 95% CI: 0.45, 0.97; I2=0%), but decreased the risk of preeclampsia in HD mothers (RR: 0.49; 95% CI: 0.31, 0.76; I2=0%). Administration with l-arginine elevated birth weights both in hypertensive and IUGR pregnant women, with WMDs of 194.70g (95% CI: 58.21, 331.20; I2=44.2%) and 134.00g (95% CI: 43.53, 224.46; I2=42.4%), respectively. However, the intervention had no effect on gestational age except in HD pregnancies (WMD: 7.05d; 95% CI: 3.16, 10.95; I2=36.5%). l-arginine administration during pregnancy significantly reduced the small for gestational age (SGA) risk of fetus both in HD (RR: 0.51; 95% CI: 0.31, 0.83; I2=0.0%) and IUGR mothers (RR: 0.46; 95% CI: 0.25, 0.88; I2=0.0%). Subgroup analyses revealed that l-arginine supplementation at <4g/d dosage or for ≥1-month duration or in the third trimester had a greater effect on birth weights in HD women without proteinuria, but a higher l-arginine dosage was more beneficial for extending gestational age and reducing the risk of SGA in older pregnancies. Additionally, intravenous infusion of l-arginine, but not oral administration, significantly increased birth weight in IUGR pregnancies with elevated NO concentrations, although the recommended amount should be confined to <4g/d. These findings provide practical guidelines for l-arginine supplementation to improve the birth outcomes of complicated pregnancies. CRD42021246290 (https://www.crd.york.ac.uk/PROSPERO).

L-Citrulline Level in Pregnant Adolescent With Severe Preeclampsia Compared to Without Preeclampsia: A Cross-sectional Study

Objectives: Numerous studies have been performed on the effect of L-arginine supplementation on improving maternal outcomes, but studies on the impact of L-citrulline in pregnancy are limited. This study aimed to evaluate the L-citrulline level in pregnant adolescents with severe preeclampsia compared to those without preeclampsia. Materials and Methods: This is a cross-sectional study among 60 adolescent pregnant women giving birth in the Emergency Room and Delivery Room in Hasan Sadikin Hospital, Bandung, Indonesia from May to October 2020. The L-citrulline levels were examined in women with severe preeclampsia (n = 30) and those without preeclampsia (n = 30). Results: The L-citrulline level in adolescent pregnancies with severe preeclampsia was lower than those without preeclampsia (79.7±40.4, 122.3±61.9 pg/mL, respectively and P=0.003). But no correlations were observed between L-citrulline levels with systolic blood pressure, diastolic blood pressure, and mean arterial pressure (MAP). Conclusions: There was a difference in serum L-citrulline level of adolescent pregnancies with severe preeclampsia and without pre-eclampsia.

The effect of l-arginine supplementation and surgical trauma on the frequency of myeloid-derived suppressor cells and T lymphocytes in tumour and blood of colorectal cancer patients

Purposel-arginine (L-arg) deficiency causes immunosuppression, but it is unknown if L-arg supplementation in colorectal cancer (CRC) patients restores immune system activity. Our objective was to investigate the effect of L-arg supplementation on the frequency of monocytic (M) and polymorphonuclear (PNM) myeloid-derived suppressor cells (M-MDSCs and PMN-MDSCs, respectively). MethodsWe enrolled 65 CRC patients (34 males, 31 females) aged 69 ​± ​10 years into a prospective, randomised, double-blind study. Twenty-eight patients received L-arg and 37 received placebo for 9 days at a dose of 10 ​g/day. The frequency changes in MDSC, CD4+ cells and the concentration of C-reactive protein (CRP) were assessed before supplementation with L-arg (test 1), after 9 days of supplementation (test 2), and after surgery on day 11 (test 3). ResultsThe frequency of M-MDSC in the tumours of patients receiving L-arg supplementation was higher than in placebo-treated patients, as was the frequency of PMN-MDSC and M-MDSC in the mucosa. CRP concentration in the serum of placebo-treated patients in test 2 was higher than in test 1, and the concentration in the serum of patients with L-arg supplementation in test 2 was lower than in test 1. Moreover, the expression pattern of the argininosuccinate synthase 1 (ASS1) suggests that CRC is not auxotrophic for L-arg. ConclusionsThe results of this study do not support the hypothesis that L-arg supplementation in CRC patients can reduce immunosuppression by decreasing the frequency of suppressor cells and increasing the frequency of effector CD4+ T cells.

Effect of L-Arginine Supplementation on Seizure Severity and Comorbid Cognitive Impairment in Pentylenetetrazole-Induced Epilepsy

Background: Cognitive impairment is a common comorbidity in epilepsy with no definitive treatment. L-arginine has been shown to improve cognition in experimental animals. Objective: This study investigated the effect of L-arginine on seizure severity and cognition in pentylenetetrazole-induced epilepsy. Materials and Methods: Forty-two male albino rats were administered pentylenetetrazole (PTZ) intraperitoneally at a dose of 35 mg/kg thrice weekly for 6 weeks. Kindled rats were divided into 5 treatment groups: DW; control administered distilled water at 10 mL/kg, LMT; lamotrigine at 62 mg/kg daily, CBZ; carbamazepine at 93 mg/kg twice daily, L-ARG; L-arginine at 100 mg/kg daily, and L-ARG+CBZ; L-arginine at 100 mg/kg daily plus carbamazepine 93 mg/kg twice daily orally. At 4 weeks on treatment, antiseizure effect was tested using sub-convulsive dose of PTZ. At week 5, cognition was assessed using Y-maze and Morris Water-Maze (MWM) tests. Serum samples were obtained for nitro-oxidative stress parameters assay at week 6. Results: There was no significant difference in seizure severity in the L-ARG versus control groups. However, L-ARG+CBZ significantly (p&lt;0.001) increased seizure latency and reduced (p&lt;0.05) Racine stage and seizure duration compared to DW. L-ARG and L-ARG+CBZ also significantly increased (p&lt;0.05) percentage correct alternation and reduced (p&lt;0.01) escape latency versus DW. There were no significant differences in serum nitro-oxidative stress parameters between the groups. Conclusion: L-arginine potentiated the antiepileptic effect of carbamazepine and improved cognition in epileptic rats. L-arginine may be repurposed for managing cognitive dysfunction in epilepsy, but the precise mechanism(s) of action needs to be investigated.

Administration of L-citrulline prevents Plasmodium growth by inhibiting/ modulating T-regulatory cells during malaria pathogenesis.

Malaria affects around 228 million people all over the globe. Malaria causing parasite Plasmodium infection leads to activation of immune responses. The growth of parasite and immune activation requires semi essential amino acids like L-arginine. Malaria infection leads to condition of hyperargininemia and low availability of nitric oxide. However, the effect of L-arginine supplementation in malaria infected mice has not been explored in in-vivo studies. In this study we have compared the effect of oral supplementation of nitric oxide donor, L-arginine and L-citrulline, in malaria infected mice Methods: To examine the effect of oral supplementation of L-arginine and L-citrulline, Plasmodium berghei infected mice were divided in different groups and respective groups were fed with L- arginine and L-citrulline, parasitemia was measured on different days. Mice was sacrificed and immunophenotyping was done on 10 days post infection. our results show that supplementation of L-arginine induces conducive environment for Plasmodium growth due to which the infected mice dies earlier than control wild type infected mice whereas L-citrulline supplementation inhibits parasite growth and mice survives for longer period of time. Flow cytometric analysis shows that supplementation of L-arginine increases cTLA-4 on T cell population, increases Treg cells leading to immunosuppression while supplementation of L-citrulline does not have effect on T cells population and number of Treg cell decrease compared to P. berghei infected mice. our results show that L-citrulline can be a better alternative than L-arginine because of lower expression of inhibitory molecules and lower parasitemia as well as increased survival of infected mice.

Effectiveness of acute L-arginine supplementation on physical performance in strength training: a systematic review and meta-analysis

Background: The oral administration of L-arginine has been related to improved physical performance due to a likely reduction in muscle fatigue, resulting from the vasodilator effect of nitric oxide on skeletal muscle. However, there is no precise and quantitative analysis of the information in the literature. The main objective of this study was to assess the effectiveness of L-arginine supplementation on physical performance in strength training with a systematic review and meta-analysis. We hypothesized that L-arginine supplementation would improve performance capacity and the effects involved in strength training. Methods: The study period was from 2010 to 2020. The inclusion process established articles with well-designed human experiments that included only L-arginine supplementation (without any additional compounds) testing the effects of L-arginine supplementation on sports performance related to strength training; identical experimental conditions in placebo or control group; and publications in the last ten years (until December 31, 2020). Three studies were included that compared L-arginine supplementation with placebo in anaerobic performance tests. Test analysis supplementation with other supplements was removed and there was no gender, age, and ethnicity level. Results: There was no significant heterogeneity (p&gt;0.05) in the analysis of the three selected articles and the effects of L-arginine supplementation in muscular endurance; performance had a mean of 0.26 (95% CI = -0.129; 0.649; p = 0.190), peak torque with a mean of -0.002 (95% CI = -0.531; 0.527; p = 0. 99) of the third series of exercises and, furthermore, when comparing the integrated effect (resistance rate with the peak torque) there was no difference with a mean of 0.168 (95% CI = -0.145; 0.481; p = 0.292). Conclusions: Acute L-arginine supplementation provides no ergogenic effect on strength training performance.

Effect of L-arginine supplementation in pregnant women with chronic hypertension and previous placenta vascular disorders receiving Aspirin prophylaxis: a randomized control trial.

The aim of the study is to evaluate the effects of supplementation with Arginine (L-Arg) 3g, (together with Magnesium (Mg) 350 mg and Salicilate (Sal) 100 mg) on maternal blood pressure (BP), uterine artery doppler PI and neonatal outcomes in women with high-risk pregnancy for chronic hypertension (CH) and other previous placenta vascular disorders (PVD) already treated with low dose of aspirin (LDA), as recommended by guidelines. We enrolled women affected by CH and other previous PVD referred to the High-Risk Clinic of the Department of Maternal and Child's Health at the University Hospital of Modena and Reggio Emilia from September 2017 to June 2019. The study design was a controlled, randomized trial of oral supplementation of L-Arg 3g (together with Mg 350 mg and Sal extract 100 mg) + LDA 100 mg/day versus only LDA 100 mg/day. Inclusion criteria were: singleton pregnancy; diagnosis of chronic hypertension, previous preeclampsia <34 weeks, previous intrauterine growth restriction (IUGR) <10th centile or previous stillbirth (SB) related to placenta vascular disorders; gestational age <14 weeks. Each woman was enrolled between 12-14 weeks gestation and underwent 24-hour ambulatory BP monitoring with an automatic device (SpaceLab 92710, Critikon, WA), repeated at 18-20th and 24-26th weeks. Moreover Uterine artery Doppler ultrasound evaluation including PI were performed at 18-20 weeks gestation and repeated at 24-26th weeks. Pregnancy outcomes data were collected in a password protected database. Seventy-nine women agreed to participate in the study. No significant differences between the demographic characteristics in the two groups were found at enrolment (Group LDA + L-Arg: 30 patients versus Group LDA: 49 patients). In the LDA-L-Arg group there is no significant increase in both systolic (127.22±12.02 and 132.75±7.51 mmHg, P=0.002) and diastolic (75.85±8.53 and 83.63±6.05 mmHg, P=0.0000) BP values at 24-26 weeks reveled in the LDA group. The value of the uterine artery Doppler median PI>95th centile at 24-26 weeks show a significant reduction in the LDA+L-Arg group respect the LDA group (seven women, 23.3% vs. 21 women, 42.9%; P=0.04). A significantly lower percentage of women received new antihypertensive drugs in the LDA+ L-Arg group than the LDA group (6.7% vs. 24.5%) (P=0.02). There was neither statistically significant difference in perinatal outcomes between the two groups, except for trend of significance. Although we found only trends of improvements of perinatal outcomes in LDA+L-Arg group, considering the promising results on BP values, uterine artery PI and the low need to start a new antihypertensive treatment, thus the resulting impact in reducing pregnancy medicalization, number of maternal-fetal well-being monitoring visits and the need of induction of labor, we believe that further studies should be performed to enlarge our observation and clarify the role of L-Arg 3g supplementation as a protective integration in high-risk pregnancies already in prophylaxis with LDA.

The effects of L-Arginine supplementation on growth performance and intestinal health of broiler chickens challenged with Eimeria spp.

This study evaluated the effects of varying levels of L-arginine (Arg) on performance and intestinal health of broilers challenged with Eimeria. Cobb 500 male chicks (n = 720) were randomly distributed in a 5 × 2 factorial arrangement (6 replicates/12 birds). The main factors were Arg levels (1.04, 1.14, 1.24, 1.34, 1.44%) and challenge or non-challenge with Eimeria. At day 12, in the challenge group, each bird received orally 12,500 Eimeria maxima, 12,500 Eimeria tenella, and 62,500 Eimeria acervulina sporulated oocysts. At 5 d postinfection (dpi), intestinal permeability was measured. At 6 and 14 dpi, performance, intestinal histomorphology, nutrient digestibility, tight junction protein (TJP) gene expression, and antioxidant markers were evaluated. Few interactions were found, and when significant, the supplementation of Arg did not counteract the negative effects of Eimeria challenge. Challenge, regardless of Arg level, increased intestinal permeability, although the expression of Claudin-1, a TJP, was upregulated. At 6 dpi, the antioxidant system was impaired by the challenge. Moreover, growth performance, intestinal histomorphology, and nutrient digestibility were negatively affected by challenge at 6 and 14 dpi. Regardless of challenge, from 0 to 14 dpi, birds fed 1.44% showed higher weight gain than 1.04% of Arg, and birds fed 1.34% showed lower feed conversion than 1.04% of Arg. At 5 dpi, intestinal permeability was improved in birds fed 1.34% than 1.04% of Arg. Moreover, 1.34% of Arg upregulated the expression of the TJP Zonula occludens-1 (ZO-1) as compared with 1.24 and 1.44% of Arg at 6 dpi. At 14 dpi, 1.44% of Arg upregulated the expression of ZO-1 and ZO-2 compared with 1.24 and 1.34% of Arg. The nutrient digestibility was quadratically influenced by Arg, whereas the antioxidant markers were unaffected. Thus, the challenge with Eimeria had a negative impact on growth and intestinal health. The dietary supplementation of levels ranging from 1.24 to 1.44% of Arg showed promising results, improving overall growth, intestinal integrity, and morphology in broilers subjected or not to Eimeria challenge.

The Effects of l-arginine Supplementation on Athletic Performance and Risk Factors of Cardiovascular Disease: Review of Current Evidence

The Effects of l-arginine Supplementation on Athletic Performance and Risk Factors of Cardiovascular Disease: Review of Current Evidence

The effect of L-arginine supplementation on obesity-related indices: A systematic review and meta-analysis of randomized clinical trials.

The clinical studies regarding the effect of L-arginine in human anthropometry have not been fully consistent, therefore, we carried out a systematic review and meta-analysis of randomized clinical trials in order to precisely evaluate and quantify the efficacy of L-arginine on weight, waist circumference, and BMI. We searched online databases including PubMed, SCOPUS, and Google Scholar for relevant articles up to September 2017. Eligible articles were reviewed by two independent investigators. Mean differences of the outcomes were used for calculation of weighted mean difference (WMD) derived from the random-effects model. Statistical heterogeneity between studies was examined using Cochran's Q-test and I2 index. Funnel plot and Egger's tests were performed to assess the publication bias. In our initial search, we found 1598 publications, of which 8 RCTs (9 treatment arms) were included. The results of the meta-analysis displayed a significant reduction in WC following L-arginine supplementation (WMD: -2.97cm; 95% CI: -4.75 to -1.18, P=0.001). However, L-arginine intervention had not elicited a significant effect on BMI (WMD: -0.51kg/m2; 95% CI: -1.11 to .08, P=0.09) and body weight (WMD: -0.57kg; 95% CI: -1.77 to 0.61, P=0.34). Subgroup analyses displayed that longer-term interventions (≥8 weeks) had a positive effect on body weight and using<8g/day L-arginine with longer duration (≥8 weeks) could significantly decrease BMI. In conclusion, this meta-analysis result suggested L-arginine supplementation could reduce waist circumference without any significant effect on body weight and body mass index.

Effects of L-arginine Supplementation and Aerobic Training on Hemodynamic Indices of Obese Men

BackgroundL-arginine is a precursor to nitric oxide, which can affect some hemodynamic indices.ObjectivesThe purpose of this study was to investigate the effect of one-month aerobic training with and without supplementation of L-arginine on hemodynamic indices in obese men.MethodsA quasi-experimental double-blind, study was carried out. Subjects (age, 30 - 45 years; BMI, 38 - 40 kg.m-2) were randomly assigned to an exercise and L-arginine supplementation group (n = 10) and placebo group (n = 10). Before and after four weeks of aerobic exercise (three 90 - 120 min sessions per week at 65% - 85% of maximal heart rate), systolic and diastolic blood pressure, and rate pressure product (RPP) were measured at rest. The analysis of variance was used to determine the interaction between the two factors of exercise and supplementation of L-arginine on the dependent variables at P < 0.05.ResultsFour weeks of aerobic exercise reduced the RPP in both groups (P ≤ 0.05), while the L-arginine group significantly reduced systolic blood pressure (116.6 ± 3.40), diastolic blood pressure (76 ± 2.29) and RPP (8918.2 ± 722.86).ConclusionsL-arginine supplementation along with four weeks of aerobic exercise can be effective in controlling hypertensive of obese men.

Effects of L-arginine Supplementation and Aerobic Training on Hemodynamic Indices of Obese Men

Background: L-arginine is a precursor to nitric oxide, which can affect some hemodynamic indices. Objectives: The purpose of this study was to investigate the effect of one-month aerobic training with and without supplementation of L-arginine on hemodynamic indices in obese men. Methods: A quasi-experimental double-blind, study was carried out. Subjects (age, 30 - 45 years; BMI, 38 - 40 kg.m-2) were randomly assigned to an exercise and L-arginine supplementation group (n = 10) and placebo group (n = 10). Before and after four weeks of aerobic exercise (three 90 - 120 min sessions per week at 65% - 85% of maximal heart rate), systolic and diastolic blood pressure, and rate pressure product (RPP) were measured at rest. The analysis of variance was used to determine the interaction between the two factors of exercise and supplementation of L-arginine on the dependent variables at P &lt; 0.05. Results: Four weeks of aerobic exercise reduced the RPP in both groups (P ≤ 0.05), while the L-arginine group significantly reduced systolic blood pressure (116.6 ± 3.40), diastolic blood pressure (76 ± 2.29) and RPP (8918.2 ± 722.86). Conclusions: L-arginine supplementation along with four weeks of aerobic exercise can be effective in controlling hypertensive of obese men.

L-Arginine Improves Sperm Motility in Threatened Coruh Trout Salmo coruhensis (Teleostei: Salmonidae)

l-arginine is a versatile amino acid and precursor of nitric oxide that provides protection for preventing free radical damage. Herein, experiments were designed to clarify the effect of l-arginine supplementation on the sperm motility of a threatened trout, Coruh trout Salmo coruhensis. Activation solution was supplemented with levels of 0 mM (Control), 2 mM, 4 mM, and 8 mM l-arginine, and motility and survival of sperm cells were assessed. The selected concentrations were determined according to results of our preliminary experiments. The sperm motility rates at l-arginine concentrations of 0, 2, 4, and 8 mM were 73.33 ± 5.77%, 76.67 ± 5.75%, 80.01 ± 0.01%, and 90.00 ± 0.05%, respectively; notility durations were 21.67 ± 2.08, 32.33 ± 3.79, 32.67 ± 1.15, and 37.00 ± 6.38 s, respectively. Significant effect of l-arginine supplementation was determined on the percentage and duration of motile spermatozoa (p < 0.05). The maximum increment was evoked at the greatest concentration (8 mM). Here, we showed that l-arginine supplement can improve sperm motility of S. coruhensis.

Effects of L-arginine Supplementation to Early Pregnant Mares on Conceptus Development and Growth

Effects of L-arginine Supplementation to Early Pregnant Mares on Conceptus Development and Growth

The effect of L-Arginine supplementation on Delayed Onset Muscle Soreness (DOMS) after eccentric heavy exercise

Introduction: L-Arginine supplementation improves antioxidant defenses through L-Arginine/nitric oxide pathways. This investigation assesses the influences of acuteL-Arginine supplementation on selected markers of delayed onset muscle soreness (DOMS) after one by one heavy eccentric exercise in healthy young females. Methods: Twelve healthy young females students of the University of Mohaghegh-Ardabili voluntarily participated in a double-blind randomized-controlled crossover trial to estimate the effects of 3g L-Arginine oral supplementation versus placebo (3g glucose) following an unaccustomed heavy eccentric exercise. L-Arginine (ARG) or placebo (PLC) was taken immediately after squat exercise, separated by 10day washout. Measurements were conducted at baseline, 24, and 48h after exercise comprising: (a) TAC (b) CK (c) LDH (d) Visual Analogue Scale (VAS) (e) Range of Motion (ROM) of both knees (f) Edema of both thighs. For data analysis software SPSS version 20 was used. To analysis the data, analysis of variance with repeated measure was used. Results: TAC significantly increased 48h after exercise compared with the pre-exercise just in ARG group (P 0.05). Conclusion: The findings of this study suggest that acute supplementation of ARG after heavy eccentric exercise may alleviate muscle damage through promoting the antioxidant capacity, protein synthesis, or decrease of lactate accumulation.

Effect of L-arginine supplementation on the hepatic phosphatidylinositol 3-kinase signaling pathway and gluconeogenic enzymes in early intrauterine growth-restricted rats.

The present study aimed to investigate the response of the phosphatidylinositol 3-kinase (PI3K) signaling pathway and gluconeogenic enzymes in intrauterine growth-restricted rats to dietary L-arginine (L-Arg) supplementation during the lactation period early in life. Pregnant Sprague-Dawley rats were randomly divided into a control group (CON), an intrauterine growth restriction group (IUGR) and an L-Arg group (LA). The pregnant rats in the CON group were fed a 21% protein diet, and those in the IUGR and LA groups were fed a 10% low protein diet, and all rats were fed a 21% protein diet after delivery. Water was available ad libitum to the pregnant rats during the 21-day lactation period, and the water provided to the LA group included 200 mg/kg/day L-Arg. Blood glucose, serum insulin, homeostasis model of assessment for insulin resistance (HOMA-IR), PI3K and protein kinase B (PKB) protein expression, and phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G-6-Pase) mRNA expression in the offspring rats were measured postnatally at 1, 3 and 8 weeks. No significant difference in blood glucose, serum insulin and HOMA-IR were identified at any time point among the three groups. PI3K and PKB expression was lower in the IUGR group offspring compared with that in the CON group offspring, but both were increased by dietary L-Arg supplementation. PEPCK mRNA and G-6-Pase mRNA expression levels in the offspring of the IUGR group were higher compared with those in the CON group but were downregulated following L-Arg supplementation. These results suggest that dietary L-Arg supplementation during the early lactation period promoted catch-up growth and reversed abnormalities in hepatic insulin signaling and gene expression of gluconeogenic enzymes in IUGR offspring rats.