• Archives of Pharmacal Research
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• v.19 no.5
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• pp.368-373
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• 1996

Nitric oxide (NO) is synthesized by various cells involved in inflammatory reactions and may then act on mast cells. In the present work, we attempted to clarify the role of this molecule on the proliferation of mouse bone marrow derived-mast cells (BMMC). Swiss 3T3 fibroblastsproduced nitrite ($NO_{2}$) and nitrate ($NO_{3}$) upon treatment with interferon ${\gamma}$(IFN-${\gamma}$). This formation was dependent of L-arginine and could be inhibited by the -L-arginine analogue $N^{G}$-monomethyl-L-arginine ($N^{G}$MMA). The effect of IFN-g was drastically invreased by cotreatment with tumor necrosis factor g(IFN-g). BMMC were maintained in vitro for as long as 30 days when cocultured with Swiss 3T3 fibroblasts. coculture with $N^{G}$MMA, significantly increased the number of BMMC. These results indicate that NO involves the inhibition of proliferation of BMMC when cocultured with Swiss 3T3 fibroblasts.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.579-584
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• 2013

In this study, we synthesized functional dendrimer derivatives as nonviral gene delivery vectors. Poly(amidoamine) dendrimer (PAMAM, generation 4) was modified to possess functional amino acids to enhance gene transfection efficiency. PAMAM G4 derivatives conjugated with L-arginine (Arg) and ${\gamma}$-aminobutyric acid (GABA) showed higher transfection efficiency and lower cytotoxicity compared to the native PAMAM G4 dendrimer. The polyplex of the PAMAM G4 derivative/pDNA was evaluated using an agarose gel retardation assay and Picogreen reagent assay. Additionally, the MTT assay was performed to examine the cytotoxicity of synthesized polymers. All PAMAM G4 derivatives showed lower cytotoxicity than PEI25kD. Particularly, PAMAM G4-GABA-Arg displayed enhanced transfection efficiency compared to the native PAMAM G4 dendrimer.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.396-402
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• 2005

Three experiments were conducted to determine the effects of dietary arginine concentrations on plasma free amino acid (PAA) concentrations in rainbow trout, Oncorhynchus mykiss (Walbaum). The first experiment was conducted to determine appropriate post-prandial and food deprivation sampling times in dorsal aorta cannulated rainbow trout averaging 519${\pm}$9.5 g (mean${\pm}$SD) at $16^{\circ}C$. Blood samples were taken at 0, 2, 3, 4, 5, 6 and 24 h after feeding (0 and 24 h blood samples were taken from the same group of fish). PAA concentrations increased by 2 h post-feeding and the concentration of all essential amino acids except histidine peaked at 5 h and returned to 0 time values by 24 h. In the second experiment dorsal aorta cannulated rainbow trout averaging 528${\pm}$11.3 g (mean${\pm}$SD) were divided into 6 groups of 4 fish to study the effect of dietary arginine levels on PAA. After 24 h food deprivation, each group of fish was fed one of six L-amino acid diets containing graded levels of arginine (0.48, 1.08, 1.38, 1.68, 1.98 or 2.58%) by intubation. Blood samples were taken at 0, 5 and 24 h after feeding. Post-prandial (5 h after feeding) plasma-free arginine concentrations (PParg) showed a breakpoint at 1.03% arginine in the diet and post-absorptive (24 h after feeding) plasma free-arginine concentrations (PAarg) showed a breakpoint at 1.38% arginine. PAarg increased linearly from fish fed diets containing arginine between 0.48% and 1.38%, and the concentrations remained constant from fish fed diets containing arginine at or above 1.38%, but were all below PParg at all time points. Results of the third experiment confirm the results that PParg concentrations from fish fed arginine deficient diets were higher than PAarg (0 or 24 h values). Thus, in contrast to mammals and birds, the PParg when arginine is present in the diet as the most limiting amino acid such that it severely limits growth, increases in plasma rather than decreases.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.902-907
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• 2000

Protamine-strong basic protein was prepared from salmon(chum salmon, Oncorhynchus keta) sperm by several pretreatment method. And there were determined yield, amino acid composition, antimicrobial and antioxidant activity of protamine on each pretreatment condition. The yield of protamine was different according to pretreatment, and ultrasonicating, homogenizing and microwaving pretreatment were about 16.0%, 15.5% and 10%, respectively. The main amino acid of P60(microwaving pretreatment for 10 min at $80^{\circ}C$) and UU6(ultrasonicating pretreatment for 60 min at $20^{\circ}C$) were arginine, proline and tryptophan, and arginine content of P60 and UU6 were 61%, 53%, respectively. On the other hand, main amino acid of M(homogenizing pretreatment by mixer) were methionine, proline and arginine, the content were 34%, 28% and 11%, respectively. Also MC(homogenizing pretreatment with $H_{2}SO_{4}$ soln. by mixer) was very different with P60, UU6 and M, the content of MC were proline 44.8% and arginine 39.7%. Prepared protamines showed antimicrobial activity to several gram(+) and gram(-) strain. In particular, the UU6 and P60 protamine has strong antimicrobial activity to Bacillus subtilis and Escherichia coli, and the activity was increased with concentration increasing. Regardless of pretreatment method, all protamine showed antioxidant activity and the $EDA_{50}$ of P60, UU6, M and MC were $101\;{\mu}g/mL$, $410\;{\mu}g/mL$, $523\;{\mu}g/mL$ and $490\;{\mu}g/mL$, respectively.

• Biomedical Science Letters
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• v.16 no.1
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• pp.25-32
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• 2010

Sprague-Dawley(SD) rats were orally administered with $N^G$-nitro-L-arginine methyl ester(L-NAME) which inhibits or blocks the production of nitric oxide from L-arginine in vascular endothelial cells and vessel tissue to statistically examine the effects of nitric oxide on some physiological changes such as blood pressure and heart rate, and to confirm the apoptosis induced by the suppressed nitric oxide activity in some related organs under light microscope. Systolic blood pressure significantly increased 28.5% by the chronic treatment of L-NAME for 8 weeks (P<0.001), no significant difference, however, was observed in heart rate between the control group and the L-NAME-treated group regardless of their age. Hematoxylin-eosin staining showed some histological alterations only in kidney among the examined organs; heart, liver, pancreas, and adrenal gland from the L-NAME-treated group. TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) test showed a strong positive reaction, representing that the chronic treatment of L-NAME facilitates apoptosis, in the cortex and medulla of kidney, but not any significance detectable in the other organs. These results conclude that chronic treatment of L-NAME significantly increases blood pressure, and that the followed inhibition of nitric oxide synthesis occurs a typical inducement of apoptosis in kidney.

• Journal of Yeungnam Medical Science
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• v.14 no.2
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• pp.337-349
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• 1997

This study was undertaken to examine the intensity of involvement of inducible nitric oxide synthase (iNOS) and cyclic GMP signal transduction pathway as one of the mechanisms of vaso-relaxative action of bacterial lipopolysaccharide (LPS) on the canine femoral artery strips. Canine femoral arteries were isolated and spiral strips of 10 mm long and 2 mm wide were made in the Tyrode solution of $0-4^{\circ}C$. The strips were prepared for isometric myography in Biancani's isolated muscle chamber containing 1 ml of Tyrode solution, which was maintained with pH 7.4 by aeration with 95% $O_2$/5% $CO_2$ at $37^{\circ}C$ and nitric oxide (NO) production was measured simulltaneously with isolated nitric oxide meter. LPS induced NO production, suppressed the phenylephrine (PE) induced contraction and enhanced the acetylcholine (ACh) induced relaxation. $N^G$-nitro-L-arginine methyl ester (L-NAME), an NOS inhibitor, methylene blue, a guanylyl cyclase inhibitor, potentiated PE induced contraction and suppressed ACh induced relaxation on the LPS treated strips. The inhibitory potency of methylene blue for LPS induced vascular hyporesponsiveness was stronger than that of L-NAME. These results suggest that in canine femoral artery, both iNOS and cyclic GMP signal trnasduction pathway are related with LPS induced vascular hyporeponsiveness, but in minor with iNOS and in major with cyclic GMP signal trnasduction pathway.

• BMB Reports
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• v.54 no.10
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• pp.516-521
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• 2021

Although arginase primarily participates in the last reaction of the urea cycle, we have previously demonstrated that arginase II is an important cytosolic calcium regulator through spermine production in a p32-dependent manner. Here, we demonstrated that rhaponticin (RPT) is a novel medicinal-plant arginase inhibitor and investigated its mechanism of action on Ca²⁺-dependent endothelial nitric oxide synthase (eNOS) activation. RPT was uncompetitively inhibited for both arginases I and II prepared from mouse liver and kidney. It also inhibited arginase activity in both aorta and human umbilical vein endothelial cells (HUVECs). Using both microscope and FACS analyses, RPT treatments induced increases in cytosolic Ca²⁺ levels using Fluo-4 AM as a calcium indicator. Increased cytosolic Ca²⁺ elicited the phosphorylations of both CaMKII and eNOS Ser1177 in a time-dependent manner. RPT incubations also increased intracellular L-arginine (L-Arg) levels and activated the CaMKII/AMPK/Akt/eNOS signaling cascade in HUVECs. Treatment of L-Arg and ABH, arginase inhibitor, increased intracellular Ca²⁺ concentrations and activated CaMKII-dependent eNOS activation in ECs of WT mice, but, the effects were not observed in ECs of inositol triphosphate receptor type 1 knockout (IP3R1^-/-) mice. In the aortic endothelium of WT mice, RPT also augmented nitric oxide (NO) production and attenuated reactive oxygen species (ROS) generation. In a vascular tension assay using RPT-treated aortic tissue, cumulative vasorelaxant responses to acetylcholine (Ach) were enhanced, and phenylephrine (PE)-dependent vasoconstrictive responses were retarded, although sodium nitroprusside and KCl responses were not different. In this study, we present a novel mechanism for RPT, as an arginase inhibitor, to increase cytosolic Ca²⁺ concentration in a L-Arg-dependent manner and enhance endothelial function through eNOS activation.

• Korean Journal of Poultry Science
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• v.22 no.1
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• pp.43-54
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• 1995

Effects of dietary protein sources and their amino acid compositions on the liver and plasma cholesterol levels in growing Single Comb white Leghorn male chicks were studied. A diet containing isolated soy protein (21% cp) was supplemented with 0.5% DL-methionine and 0.3% L-glycine. and another diet containing casein(21% cp) was supplemented with 1.5% L-arginine HCl, 0.4% DL-methionine. and 1.0% L-glycine. Plasma cholesterol level was markedly lower in groups force-fed the diets containing either soy protein or casein supplemented with amino acids compared to those found in birds fed corresponding diets without amino acids supplementation. The cholesterol lowering effect of the casein diet. when balanced with various supplemental amino acids appeared to be due to arginine instead of methionine or glycine. It is likely that amino acid balance rather than the composition of a specific amino acid is one of the major factors determining the effect of dietary protein sources on the blood cholesterol levels in chicks.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.407-412
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• 2000

The presence of the nitric oxide synthase (NOS) enzyme from Salmonella typhimurium (S. typhimurium) was identified by measuring radiolabeled L-$[^3H]$citrulline and NO, and Western blot analysis. NOS was partially purified by both Mono Q ion exchange and Superose 12HR size exclusion column chromatography, sequentially. The molecular weight of NOS was estimated to be 93.3 kDa by Western blot analysis. The enzyme showed a significant dependency on the typical NOS cofactors; an apparent Km for L-arginine of 34.7 mM and maximum activity between $37^{\circ}C$ and $43^{\circ}C$. The activity was inhibited by NOS inhibitors such as aminoguanidine and $N^{G}$ $N^{G}$-dimethyl-L-arginine. taken together, partially purified NOS in S. typhimurium is assumed to be a different isoform of mammalian NOSs.OSs.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.4
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• pp.213-216
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• 2006

The present study was aimed to determine whether nitric oxide (NO) plays a role in the regulation of aquaporin (AQP) channels in the kidney. Male Brattleboro rats ($250{\sim}300\;g$ body weight) were used. The experimental group was treated with $N^G$-nitro-L-arginine methyl ester (L-NAME, 100 mg/L drinking water) for 1 week, and cotreated with indomethacin (5 mg/kg, twice a day, i.p.) for the last two days. Control groups were treated with either L-NAME for 1 week, indomethacin for 2 days, or without any drug treatment. The abundance of AQP1, AQP2 and AQP3 proteins in the kidney was determined by Western blot analysis. Indomethacin downregulated AQP channels, whereas L-NAME by itself showed no significant effects on them. The indomethacin-induced downregulation of AQP2 and AQP3 was significantly blunted in L-NAME-treated rats, while that of AQP1 was not affected. These results suggest that endogenous NO, when stimulated, may downregulate AQP channels that are specifically regulated by AVP/cAMP pathway in the kidney.