Arginine Concentrations Research Articles

Microcirculatory Function during Endotoxemia-A Functional Citrulline-Arginine-NO Pathway and NOS3 Complex Is Essential to Maintain the Microcirculation.

Competition for the amino acid arginine by endothelial nitric-oxide synthase (NOS3) and (pro-)inflammatory NO-synthase (NOS2) during endotoxemia appears essential in the derangement of the microcirculatory flow. This study investigated the role of NOS2 and NOS3 combined with/without citrulline supplementation on the NO-production and microcirculation during endotoxemia. Wildtype (C57BL6/N background; control; n = 36), Nos2-deficient, (n = 40), Nos3-deficient (n = 39) and Nos2/Nos3-deficient mice (n = 42) received a continuous intravenous LPS infusion alone (200 μg total, 18 h) or combined with L-citrulline (37.5 mg, last 6 h). The intestinal microcirculatory flow was measured by side-stream dark field (SDF)-imaging. The jejunal intracellular NO production was quantified by in vivo NO-spin trapping combined with electron spin-resonance (ESR) spectrometry. Amino-acid concentrations were measured by high-performance liquid chromatography (HPLC). LPS infusion decreased plasma arginine concentration in control and Nos3−/− compared to Nos2−/− mice. Jejunal NO production and the microcirculation were significantly decreased in control and Nos2−/− mice after LPS infusion. No beneficial effects of L-citrulline supplementation on microcirculatory flow were found in Nos3−/− or Nos2−/−/Nos3−/− mice. This study confirms that L-citrulline supplementation enhances de novo arginine synthesis and NO production in mice during endotoxemia with a functional NOS3-enzyme (control and Nos2−/− mice), as this beneficial effect was absent in Nos3−/− or Nos2−/−/Nos3−/− mice.

Vitamin D role in endothelial dysfunction development in patients with polycystic ovarian syndrome

Background. The study was aimed to determine the correlation between the blood concentration of vitamin D and factors that influence the function of the endothelium and the hemodynamic of gonads in women with polycystic ovary syndrome (PCOS). Material and methods. Sixty women aged from 18 to 26 years were examined: 30 women with a diagnosis of PCOS and 30 healthy women. The blood serum concentration of vitamin D, C-reactive protein (CRP), interleukin-6 (IL-6), homocysteine (Hcy), nitrites/nitrates (NOx), and arginine were investigated. Maximum systolic velocity (Vmax), resistance index (RI), and pulsatility index (PI) were measured with Doppler ultrasound. Cholecalciferol was used in a dose of 4000 IU per day for 12 weeks for the correction of deficiency of vitamin D. Results. The patients with PCOS were found to have a lower (Р<0.001) average vitamin D than healthy women. The reduction of vitamin D concentration was combined with an increase (P<0.001) in the average concentration of NOx and a decrease in arginine. It was found a positive association between vitamin D and arginine (r=0.391; P<0.05), between NOx and CRP (r=0.432; P<0.02), IL-6 (r=0.476; P<0.01), Vmax (r=0.383; P<0.05), RI (r=0.369; P<0.05), PI (r=0.380; P<0.05) and reverse correlation with arginine (r=–0.375; P<0.05). It was not found an association between NOx and vitamin D (r=0.207; P>0.05), Hcy (r=0.176; P>0.05); between vitamin D and Vmax (r=0.231; P>0.05), RI (r=0.201; P>0.05), PI (r=0.181; P>0.05). The therapy of cholecalciferol level was accompanied by an increase (P<0.001) in concentrations of vitamin D, arginine (P<0.05) and a decrease in NOx (P<0.02), IL-6 (P<0.05), SRP (P<0.001), Hcy (P<0.001), Vmax (P<0.001), RI (P<0.001), PI (P<0.01), quantity of antral follicles (P<0.001), and the growth of follicles (P<0.001). However, none of the studied indicators reached the indicators in healthy women. Conclusions. The deficiency of vitamin D is associated with increased markers of chronic inflammation, homocysteine, nitrate/nitrites, reduced concentration of arginine that provokes the development of endothelium dysfunction and, therefore, the hemodynamics disorders and folliculogenesis in the ovary.

The contribution of l-Arginine to the mass transfer performance of CO2 absorption by an aqueous solution of methyl diethanolamine in a microreactor

The current study investigates the effect of adding l-arginine as a potential promoter for the conventional methyl diethanolamine (MDEA) in the carbon dioxide (CO2) capture process in a T-junction microreactor. The overall gas-phase mass transfer coefficient (KGaV) and CO2 absorption efficiency (ef) were evaluated under distinct operating conditions, including total amine + amino acid concentration of 50 wt%, the liquid flow rate of 3–9 mL min−1, and gas flow rate of 120–300 mL min−1. The composition of different concentrations in the mixture were as MDEA (50%), MDEA + ARG (46 + 4%), MDEA + ARG (42 + 8%),MDEA + ARG (38 + 12%). The impact of amino acid concentration on the physical properties of the aqueous MDEA solution was also compared in four solutions. The results indicated that increasing the arginine concentration from 4 wt% to 12 wt% intensifies the ef values from 78.91 to 92.7%, while the solution density and viscosity grows slightly. Furthermore, the values of the KGaV in the CO2 absorption enhanced from 14.34 kmol/(m3 kPa h) in aqueous MDEA (50%) solution to 63 kmol/(m3 kPa h) in MDEA + ARG (38 + 12%). It confirmed that arginine could apply as a potential chemical activator in the mixture of MDEA-ARG to intensify the absorption of CO2 in the post-combustion CO2 capture processes.

DEVELOPMENT OF ARGININE DEIMINASE BASED CONDUCTOMETRIC BIOSENSOR FOR ARGININE DETERMINATION

For the first time, a conductometric enzyme biosensor was developed to determine arginine concentrations. The bioselective membrane of the biosensor was formed by immobilization of arginine deiminase on the surface of gold planar transducer using covalent crosslinking of glutaraldehyde with bovine serum albumin. An effect of the solution characteristics (ionic strength, buffer capacity) on the biosensor functioning was studied. The proposed monoenzyme biosensor was shown to have high sensitivity to arginine (minimum limit of detection - 5 μM) and good selectivity towards possible interferents. The linear range of determination was from 10 to 800 μM. The biosensor sensitivity to arginine is 72 μS /μM. The developed biosensor was demonstrated to be promising for the arginine analysis in real samples.

Antifungal Activity of Peptides Derived From Iranian Traditional Kefir

Background: Probiotic products contain metabolites that have positive effects on the intestinal microorganisms and well-being of the host as well as possess antimicrobial properties. Objective: This study aimed to investigate the antifungal activities of the water-soluble peptides (WSPs) found in ewe and cow milk kefir fermented by the traditional kefiran of Semnan (Semnan province, Iran). Materials and Methods: Kefir samples were prepared by inoculating Iranian traditional kefiran into pasteurized milk. WPSs were extracted and antifungal activity was evaluated. Results: During the 28-day storage, the concentration of the amino acids increased except for a decrease detected in the concentration of arginine, aspartic acid, cysteine, and glycine; and the total amino acid concentration in ewe milk and kefir was higher than that in cow’s milk and kefir. The WSPs of both kefir samples showed considerable inhibitory activities against the growth of Candida albicans and Aspergillus niger, but Penicillium sp. had the lowest sensitivity when treated with WSPs. The antifungal activity of WSPs of ewe kefir was significantly higher than that of cow kefir. The highest growth inhibitory potential of WSPs between two kefir samples was found for C. albicans. The antifungal potential of WSPs of ewe kefir was considerably higher than that of cow kefir. Conclusion: The higher antifungal potential of ewe kefir was likely associated with the high concentration of protein, extensive degradation of proteins, and diversity of amino acids produced during the fermentation.

Coordinated action of multiple transporters in the acquisition of essential cationic amino acids by the intracellular parasite Toxoplasma gondii.

Intracellular parasites of the phylum Apicomplexa are dependent on the scavenging of essential amino acids from their hosts. We previously identified a large family of apicomplexan-specific plasma membrane-localized amino acid transporters, the ApiATs, and showed that the Toxoplasma gondii transporter TgApiAT1 functions in the selective uptake of arginine. TgApiAT1 is essential for parasite virulence, but dispensable for parasite growth in medium containing high concentrations of arginine, indicating the presence of at least one other arginine transporter. Here we identify TgApiAT6-1 as the second arginine transporter. Using a combination of parasite assays and heterologous characterisation of TgApiAT6-1 in Xenopus laevis oocytes, we demonstrate that TgApiAT6-1 is a general cationic amino acid transporter that mediates both the high-affinity uptake of lysine and the low-affinity uptake of arginine. TgApiAT6-1 is the primary lysine transporter in the disease-causing tachyzoite stage of T. gondii and is essential for parasite proliferation. We demonstrate that the uptake of cationic amino acids by TgApiAT6-1 is 'trans-stimulated' by cationic and neutral amino acids and is likely promoted by an inwardly negative membrane potential. These findings demonstrate that T. gondii has evolved overlapping transport mechanisms for the uptake of essential cationic amino acids, and we draw together our findings into a comprehensive model that highlights the finely-tuned, regulated processes that mediate cationic amino acid scavenging by these intracellular parasites.

Prospective study on the association between serum amino acid profiles and depressive symptoms among the Japanese working population

ObjectiveAccumulating evidence suggests that amino acids, particularly tryptophan and glutamate, play an important role in the pathology of depression, but prospective epidemiologic data on this issue is scarce. We examined the association between circulating amino acids and the risk of depressive symptoms in a Japanese working population.MethodsParticipants were 841 workers who were free from depressive symptoms and provided blood at baseline and completed 3-yr follow-up survey. 30 varieties of amino acid concentrations in serum were measured using liquid chromatography/mass spectrometry. Depressive symptoms were defined using the Center for Epidemiologic Studies Depression Scale. Logistic regression was used to calculate the odds ratios of depressive symptoms according to serum amino acids with adjustment for lifestyle factors.ResultsA total of 151 (18.0%) workers were newly identified as having depressive symptoms at the follow-up. Baseline tryptophan and glutamate concentrations in serum were not appreciably associated with the risk of depressive symptoms. Risk of depressive symptoms tended to increase with increasing arginine concentrations; the multivariable-adjusted odds ratio for the highest versus lowest tertile of serum arginine was 1.65 (95% confidence interval: 0.96–2.83; P for trend = 0.07). No clear association was found for other amino acids.ConclusionsResults of the present study do not support a significant role of circulating amino acids in the development of depressive symptoms among Japanese.

Symmetric Dimethylarginine is Altered in Patients After Myocardial Infarction and Predicts Adverse Outcomes.

PurposeAcute myocardial infarction (AMI) is the leading cause of morbidity and mortality worldwide. Damage to the endothelium is the earliest event in atherothrombosis, including AMI. Nitric oxide (NO), an endothelium-derived compound, protects the vasculature from damage. This study evaluated whether an association exists between plasma concentration of endogenous NO-related pathway metabolites linked to AMI and major adverse cardiovascular events (MACE) after AMI.MethodsWe compared plasma concentrations of NO-related pathway metabolites in patients after AMI (n=60) and healthy controls (n=27) and investigated the prognostic value of these metabolites for post-AMI MACE development over a median of 3.5-years. In search of biomarkers, we compared plasma concentrations of dimethylarginines (ADMA, SDMA), citrulline, arginine and ornithine using ultra performance liquid chromatograph coupled with a mass spectrometer.ResultsPatients after AMI had higher concentrations of dimethylarginines, compared to controls (p=0.0068, p<0.0001, respectively). Conversely, the concentration of citrulline was lower in the AMI group (p=0.0006). The concentration of SDMA was higher in patients who developed MACE than in those who did not (p=0.015). SDMA was the only independent predictor of MACE in multivariate analysis (p=0.023). There was an intermediate, negative correlation between plasma SDMA level and platelet reactivity (r=−0.33, p=0.02).ConclusionPlasma concentration of dimethylarginines differs between patients with AMI and healthy volunteers. The study’s novel finding is that SDMA is an independent predictor of MACE during a 3.5 year follow-up period after AMI.

Terahertz Absorption Properties of Two Solid Amino Acids and Their Aqueous Solutions

A new type of embedded cyclic olefin copolymer microfluidic chip was designed and combined with terahertz (THz) technology to study the effects of glycine and arginine on the THz wave absorption characteristics. This study aims to understand the interactions between solid amino acid molecules and between amino acid and water molecules and to determine the changes in their microstructure. By observing the intensity of the time domain spectra in the range of 0.2–2.6 THz, we found that, as the concentration of glycine and arginine increased, the THz transmission gradually decreased. It can be inferred that the molecular structure and quantity of different amino acids have different influence on the hydrogen bond, which affects the absorption coefficient in solution. It was also found that the terahertz technique is able to identify the solid amino acid species better, and it can also perform some species identification for liquid amino acids. These results provide a reference for future studies on the terahertz absorption properties of amino acid samples. Moreover, Gaussian16 software was used to calculate the terahertz spectra using the density functional theory, B3LYP functional, and 6-31G basis set. Additionally, Gaussian View6 video software provided the frequency values, molecular vibration modes of the theoretical absorption peaks of glycine, arginine, and its aqueous solutions in the frequency range of 0.2–2.6 THz, which offers theoretical support for future studies.

Determination of serum methylarginine levels by tandem mass spectrometric method in patients with ankylosing spondylitis

Our aim in this study was to measure serum levels of methylarginines and related metabolites in patients with ankylosing spondylitis (AS), moreover, to investigate the relationship between these parameters and various clinical and laboratory parameters of patients with AS. The study included 60 patients with AS and 60 healthy volunteers. Serum asymmetric dimethylarginine (ADMA), L-N monomethylarginine (L-NMMA), symmetric dimethylarginine (SDMA), arginine (Arg), homoarginine (hArg), ornithine, and citrulline concentrations were measured with tandem mass spectrometry. In addition, participants were divided into three groups according to the treatment regimen: TNF-α inhibitor group (n = 25), conventional therapy group (n = 35), and control group (n = 60). These groups were compared in terms of serum levels of methylarginine pathway metabolites and various biochemical parameters. It was found that total methylated arginine load significantly increased in patients with AS (p < 0.001), and the Arg/ADMA ratio was positively correlated with HDL levels and negatively correlated with glucose, ESR, total cholesterol, triglyceride, and LDL levels. In addition, serum ADMA, SDMA, total methylated arginine load, and CRP levels were lower (p < 0.05) in the TNF-α group compared to the conventional treatment group. To thebestof ourknowledge, this is the first study to comprehensively investigate serum methylarginine levels in patients with AS. Elevated total methylated arginine load and decreased global arginine bioavailability ratio (GABR) indicate that NO metabolism is impaired in patients with AS. Therefore, the increased cardiovascular risk in patients with AS may be related to the decreased NO production or bioavailability due to the elevated total methylarginine load.

Cortisol enhances citrulline synthesis from proline in enterocytes of suckling piglets.

There are marked decreases in plasma concentrations of cortisol and arginine (an essential amino acid for neonates) as well as intestinal citrulline synthesis in piglets during the first 14days of life. The objective of this study was to test the hypothesis that increasing plasma cortisol concentrations by cortisol administration may prevent the decline in intestinal citrulline and arginine synthesis from proline, thereby possibly increasing plasma arginine concentration in suckling piglets and their growth. Seven-day-old pigs reared by sows received daily intramuscular injections of hydrocortisone 21-acetate (25mg/kg) or vehicle solution (saline) (n = 10/group). At 14days of age, piglets were used to prepare jejunal enterocytes. Cells were incubated at 37°C for 30min in oxygenated Krebs buffer containing 5mM glucose, 2mM [U-14C]proline, and 2mM glutamine. Cortisol treatment increased plasma cortisol concentration, mitochondrial proline oxidase and N-acetylglutamate synthase activities, cytosolic argininosuccinate lyase activity, and the intracellular concentrations of N-acetylglutamate and carbamoyl phosphate for citrulline and arginine synthesis. However, cortisol treatment induced the expression of intestinal arginase-II for arginine hydrolysis, resulting in no change in plasma arginine concentration. Administration of cortisol had no effect on milk consumption or the whole-body growth rate of piglets, but increased villus height in the jejunum and ileum. Collectively, these results suggest an important role for proline oxidase and N-acetylglutamate in regulating citrulline and arginine synthesis from proline in pig enterocytes. Because proline catabolism plays an important role in modulating protein synthesis, cell proliferation, and arginine production, our findings may have important implications for understanding the role of proline oxidase in the growth and health of the mammalian small intestine.

Maternal lysine, methionine and choline supplementation in twin-bearing Merino ewes during mid-to-late gestation does not alter pregnancy outcomes or progeny growth and survival

High twin lamb mortality in Merino sheep is a major cost for the Australian wool and sheep meat industry. Most lambs die within three days of birth due to low birthweight and/or complications arising during parturition. Maternal arginine supplementation can potentially increase birthweight by improving utero-placental haemodynamics; but availability and cost of rumen-protected arginine are barriers. Therefore, we sought to increase circulating concentrations of arginine, lamb birthweight and survival by supplementing twin-bearing Merino ewes with lysine, methionine and choline from day 80 of gestation (dG 80) to parturition. Each day, ewes were individually fed a supplement (barley, pea, pollard and molasses) with addition of either 14 g lysine, 7 g methionine and 7 g choline (amino acid; AA; n = 48); or no amino acids (control; CTL; n = 48). Supplementation did not alter circulating amino acid profiles in ewes at dG 120. Parturition difficulty of ewes and meconium staining of lambs did not differ between AA and CTL groups. Rectal temperatures during the first 24 h of life and serum IgG concentrations (indicative of colostrum intake) at 24 h after birth were similar in lambs born to AA and CTL ewes. AA supplementation did not alter lamb weights from birth to weaning (~three months of age), or lamb survival to weaning (CTL: 75%; AA: 84.8%, P > 0.05). The lack of response to maternal supplementation with this combination of rumen-protected lysine, methionine and choline suggests that alternate strategies are needed to increase maternal arginine abundance and twin lamb survival.

A Cross-Talk between the Erythrocyte L-Arginine/ADMA/Nitric Oxide Metabolic Pathway and the Endothelial Function in Subjects with Type 2 Diabetes Mellitus.

(1) Background: Type-2-diabetes-mellitus (DM) is one the most important cardiovascular-risk-factors. Among many molecules regulating vascular tone, nitric oxide appears to be the most pivotal. Although micro- and macrovascular-abnormalities are extensively studied, the alterations in the nitric-oxide-metabolic-pathway require further investigations. Additionally, the role of erythrocytes in the vascular tone regulation has not been extensively explored. The aim of this study was to evaluate the endothelial-function and the nitric-oxide-metabolic-pathway in erythrocytes and plasma of diabetic individuals. (2) Methods: A total of 80 subjects were enrolled in this cross-sectional study, including 35 patients with DM and 45 healthy individuals. The endothelial-function was evaluated in response to different stimuli. (3) Results: In the DM group, decreased Arginine and citrulline concentrations in the plasma compartment with reduced Arginine/ADMA and ADMA/DMA-ratios were observed. Preserved nitric-oxide-metabolism in erythrocytes with reduced citrulline level and significantly higher NO-bioavailability were noted. Significant endothelial dysfunction in DM individuals was proved in response to the heat-stimulus. (4) Conclusions: DM patients at an early stage of disease show significant differences in the nitric-oxide-metabolic-pathway, which are more pronounced in the plasma compartment. Erythrocytes constitute a buffer with a higher nitric-oxide-bioavailability, less affected by the DM-related deviations. Patients at an early-stage of DM reveal endothelial-dysfunction, which could be diagnosed earlier using the laser-Doppler-flowmetry.

Longitudinal associations of physical activity with plasma metabolites among colorectal cancer survivors up to 2\xa0years after treatment

We investigated longitudinal associations of moderate-to-vigorous physical activity (MVPA) and light-intensity physical activity (LPA) with plasma concentrations of 138 metabolites after colorectal cancer (CRC) treatment. Self-reported physical activity data and blood samples were obtained at 6 weeks, and 6, 12 and 24 months post-treatment in stage I-III CRC survivors (n = 252). Metabolite concentrations were measured by tandem mass spectrometry (BIOCRATES AbsoluteIDQp180 kit). Linear mixed models were used to evaluate confounder-adjusted longitudinal associations. Inter-individual (between-participant differences) and intra-individual associations (within-participant changes over time) were assessed as percentage difference in metabolite concentration per 5 h/week of MVPA or LPA. At 6 weeks post-treatment, participants reported a median of 6.5 h/week of MVPA (interquartile range:2.3,13.5) and 7.5 h/week of LPA (2.0,15.8). Inter-individual associations were observed with more MVPA being related (FDR-adjusted q-value < 0.05) to higher concentrations of arginine, citrulline and histidine, eight lysophosphatidylcholines, nine diacylphosphatidylcholines, 13 acyl-alkylphosphatidylcholines, two sphingomyelins, and acylcarnitine C10:1. No intra-individual associations were found. LPA was not associated with any metabolite. More MVPA was associated with higher concentrations of several lipids and three amino acids, which have been linked to anti-inflammatory processes and improved metabolic health. Mechanistic studies are needed to investigate whether these metabolites may affect prognosis.

Quality characteristics and antioxidant activity of the mango (Mangifera indica) fruit under arginine treatment

Mango fruit is one of the most important fruits in terms of nutritional value. One of the important characters of mango is the presence of antioxidants such as polyphenols, carotenoids, and anthocyanins in its fruits and vegetables. These compounds are involved in preventing diseases and maintaining health in humans. Amino acids have been used to preserve and enhance fruits quality. In this study, the mango fruits of a local cultivar were sprayed with the arginine amino acid at concentrations of 0, 200, and 400 µM at the time of fruit formation and 10 days after this stage. Results showed that total phenolics, anthocyanins, carotenoids, antioxidant capacity, total soluble solids, pH, fruit weight, and seed weight of the fruits increased with the increase in arginine concentration and 400 μM arginine had a better effect on these characters. Comparison of the times of application indicated that the second stage of the foliar application was generally more effective than the first stage in increasing the studied characters.

Amino Acids Composition of Some Wild Edible Mushrooms from Southern Cross River State, Nigeria

Aims: To document the amino acid content of six wild edible mushrooms - Lentinus squarrosulus Mont., Auricularia auricular-judae (Bull.) Wettst., Mycetinis copelandii (Desjardin) A.W. Wilson &amp; Desjardin, Baeospora myosura (Fr.) Singer, Pleurotus ostreatus (Jacq. ex. fr) Kummer and Volvariella volvacea (Bull. ex. Fr.) Singer - found in southern Cross River State, Nigeria.&#x0D; Place and duration of study: Department of Plant and Ecological Studies, University of Calabar, Cross River State, Nigeria, between May 2018 and August 2018.&#x0D; Methodology: The amino acids content of these mushrooms were quantitatively estimated. The samples were obtained and analyzed for amino acids on dry weight basis using standard methods.&#x0D; Results: The amino acid analysis quantitatively estimated the alanine, arginine, aspartic acid, cystine, glutamic acid, glycine, histidine, Isoleucine, leucine, lysine, methionine, norleucine, phenylalanine, proline, serine; threonine; tryptophan; tyrosine and valine component of the mushroom samples. All the mushrooms studied contained nine essential, five conditionally essential and four non-essential amino acids with glutamic acid as the most predominant (values ranging from 6.66 to 17.26g/100g protein). Cysteine (0.30-0.48g/100g protein) and methionine (0.64-1-1.7g/100g protein) were the lowest in concentration. The concentrations of five of these essential amino acids phenylalanine (3.55 mg/100g protein), valine (3.62 mg/100g protein), threonine (3.39 mg/100g protein), tryptophan (1.58 mg/100g protein), and lysine (3.23 mg/100g protein) in P. ostreatus were significantly (P≤0.05) higher than found in the other mushrooms. For the nonessential and conditionally essential amino acids, the concentrations of arginine (6.02 mg/100g protein), aspartic acid (6.88 mg/100g protein), cysteine (0.48 mg/100g protein), glutamine (17.26 mg/100g protein) and glycine (2.61 mg/100g protein) in P. ostreatus were significantly higher (P≤0.05) than found in the other mushrooms.&#x0D; Conclusion: This information reveals that mushrooms are potential sources of quality protein with substantial proportion of essential amino acids indicating they can play a significant role in the fight against malnutrition.

The Protective Effects of a Combination of an Arginine Silicate Complex and Magnesium Biotinate Against UV-Induced Skin Damage in Rats

The purpose of this study was to observe the effects of a novel combination of inositol-stabilized arginine silicate complex (ASI) and magnesium biotinate (MgB) on the prevention of skin damage after UVB exposure in rats. Forty-nine Sprague-Dawley rats were randomized into one of the following groups: (1) NC, normal control, (2) SC, shaved control, (3) UVB (exposed to UVB radiation), (4) ASI+MgB-L (Low Dose), (5) ASI+MgB-H (High Dose), (6) ASI+MgB-L+MgB cream, (7) ASI+MgB-H+MgB cream. The results showed that ASI+MgB treatment alleviated the macroscopic and histopathological damages in the skin of rats caused by UVB exposure. Skin elasticity evaluation showed a similar trend. ASI+MgB increased serum Mg, Fe, Zn, Cu, Si, biotin, and arginine concentrations and skin hydroxyproline and biotinidase levels while decreasing skin elastase activity (p < 0.05) and malondialdehyde (MDA) concentration (p < 0.001). Moreover, ASI+MgB treatment increased skin levels of biotin-dependent carboxylases (ACC1, ACC2, PC, PCC, MCC) and decreased mammalian target of rapamycin (mTOR) pathways and matrix metalloproteinase protein levels by the regulation of the activator protein 1 (AP-1), and mitogen activated protein kinases (MAPKs) signaling pathways. In addition, ASI+MgB caused lower levels of inflammatory factors, including TNF-α, NFκB, IL-6, IL-8, and COX-2 in the skin samples (p < 0.05). The levels of Bax and caspase-3 were increased, while anti-apoptotic protein Bcl-2 was decreased by UVB exposure, which was reversed by ASI+MgB treatment. These results show that treatment with ASI and MgB protects against skin damage by improving skin appearance, elasticity, inflammation, apoptosis, and overall health.

Effects of mid-gestational l-citrulline supplementation to twin-bearing ewes on umbilical blood flow, placental development, and lamb production traits.

The objective of the study was to examine how l-citrulline supplementation to ewes during mid-gestation influences placental activity, placental blood flow, lamb body weight, and carcass characteristics. Two studies were completed. A pharmacokinetic study to compare circulating plasma amino acid concentrations after a single intravenous injection of 155 µmol/kg BW l-citrulline or after an isonitrogenous amount of l-alanine (control; 465 µmol/kg BW). Increases (P < 0.05) in circulating citrulline concentrations were detected for 8 h after l-citrulline injection versus the control. Similarly, increases (P < 0.05) in circulating arginine concentrations were detected for 24 h after l-citrulline treatment. The second study used 12 ewes with twin pregnancies. Daily intravenous injections of either l-citrulline or l-alanine were administered for 39 d from d 42–45 to 81–84 of gestation. Ewes were limit-fed at 85% daily energy requirements during the injection period. A decrease (P < 0.0001) in body weight was observed in both treatment groups during this period. No treatment differences were observed in circulating pregnancy-specific protein B concentrations or placental blood flow during the treatment and post-treatment gestational period. No treatment differences were observed in lamb survival nor in lamb birth, weaning and slaughter weights. Treatment did not influence lamb carcass composition or organ weights. However, there was a tendency (P = 0.10) for an increase in antral follicle numbers in ovaries from ewe lambs derived from ewes treated with l-citrulline. In summary, a daily l-citrulline injection increased both circulating citrulline and arginine concentrations in ewes, but daily l-citrulline injections during mid-gestation did not produce any detectable changes in placental activity and blood flow, neonatal and postnatal lamb development, and lamb carcass composition at slaughter. In conclusion, no benefits in placental function and lamb development were observed after providing l-citrulline during mid-gestation in ewes exposed to a mild energy restriction, but there was an indication that follicle numbers in ewe lambs were positively influenced by l-citrulline treatment during fetal development.

Cytotoxic Potential of Purified Arginine Deiminase from Streptococcus spp

The results that presented in the study were based on collecting one hundred and ten clinical samples of oralcavity, burns and wounds. Primary and secondary diagnositic showed that 14 out of these isolates belongedto Streptococcus spp.. The ability of these isolates in arginine deiminase enzyme production was screenedand the results showed that these isolates were arginine deiminase producers with variable degrees. It hasbeen found that one of these isolates which were Streptococcus mitis S5 had the highest specific activity(0.184 U/mg protein), therefore it was chosen for further study. Results of the optimum conditions forarginine deaminase production reveal that the maximum arginine deaminase production was achieved aftersupplementation of the production medium (pH 7.5) with 1% maltose as carbon source, 1.2% tryptone asnitrogen source, 30mM as arginine concentration and incubated at 37ºC for 18h. Under these conditions,ADI purified in three steps including; precipitation with 70% saturated ammonium sulphate, dialysis then ionexchange chromatography using DEAE- cellulose column and the last step was gel filtration chromatographythroughout Sephadex G150 column. Specific activity of the purified enzyme was increased up to 18 U/mgwith 5 folds of purification and 70.8 % enzyme recovery.

Application of Nitrate, Ammonium, or Urea Changes the Concentrations of Ureides, Urea, Amino Acids and Other Metabolites in Xylem Sap and in the Organs of Soybean Plants (Glycine max (L.) Merr.).

Soybean (Glycine max (L.) Merr.) plants form root nodules and fix atmospheric dinitrogen, while also utilizing the combined nitrogen absorbed from roots. In this study, nodulated soybean plants were supplied with 5 mM N nitrate, ammonium, or urea for 3 days, and the changes in metabolite concentrations in the xylem sap and each organ were analyzed. The ureide concentration in the xylem sap was the highest in the control plants that were supplied with an N-free nutrient solution, but nitrate and asparagine were the principal compounds in the xylem sap with nitrate treatment. The metabolite concentrations in both the xylem sap and each organ were similar between the ammonium and urea treatments. Considerable amounts of urea were present in the xylem sap and all the organs among all the treatments. Positive correlations were observed between the ureides and urea concentrations in the xylem sap as well as in the roots and leaves, although no correlations were observed between the urea and arginine concentrations, suggesting that urea may have originated from ureide degradation in soybean plants, possibly in the roots. This is the first finding of the possibility of ureide degradation to urea in the underground organs of soybean plants.