• Biomolecules & Therapeutics
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• 제32권1호
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• pp.154-161
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• 2024

Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disorder that causes progressive paralysis. L-Citrulline is a nonessential neutral amino acid produced by L-arginine via nitric oxide synthase (NOS). According to previous studies, the pathogenesis of ALS entails glutamate toxicity, oxidative stress, protein misfolding, and neurofilament disruption. In addition, L-citrulline prevents neuronal cell death in brain ischemia; therefore, we investigated the change in the transport of L-citrulline under various pathological conditions in a cell line model of ALS. We examined the uptake of [¹⁴C]L-citrulline in wild-type (hSOD1wt/WT) and mutant NSC-34/ SOD1^G93A (MT) cell lines. The cell viability was determined via MTT assay. A transport study was performed to determine the uptake of [¹⁴C]L-citrulline. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis was performed to determine the expression levels of rat large neutral amino acid transported 1 (rLAT1) in ALS cell lines. Nitric oxide (NO) assay was performed using Griess reagent. L-Citrulline had a restorative effect on glutamate induced cell death, and increased [¹⁴C]L-citrulline uptake and mRNA levels of the large neutral amino acid transporter (LAT1) in the glutamate-treated ALS disease model (MT). NO levels increased significantly when MT cells were pretreated with glutamate for 24 h and restored by co-treatment with L-citrulline. Co-treatment of MT cells with L-arginine, an NO donor, increased NO levels. NSC-34 cells exposed to high glucose conditions showed a significant increase in [¹⁴C]L-citrulline uptake and LAT1 mRNA expression levels, which were restored to normal levels upon co-treatment with unlabeled L-citrulline. In contrast, exposure of the MT cell line to tumor necrosis factor alpha, lipopolysaccharides, and hypertonic condition decreased the uptake significantly which was restored to the normal level by co-treating with unlabeled L-citrulline. L-Citrulline can restore NO levels and cellular uptake in ALS-affected cells with glutamate cytotoxicity, pro-inflammatory cytokines, or other pathological states, suggesting that L-citrulline supplementation in ALS may play a key role in providing neuroprotection.

• Journal of Microbiology and Biotechnology
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• 제2권2호
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• pp.102-107
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• 1992

For the purpose of producing L-ornithine by microbial fermentation, mutant strains were developed from glutamate-producing bacteria by mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine (NTG) and UV irradiation. Brevibacterium ketoglutamicum BK1046, a L-citrulline auxotroph which is also resistant to arginine hydroxamate (Arghx), was isolated and selected as the best producer of L-ornithine. This strain was capable of producing L-ornithine at a concentration of 24 g/l after 69 hours of cultivation in the 21 jar fermentor. The optimum supplementary level of L-arginine, a substitute for L-citrulline, was found to be about 0.2 g/l in the shake-flask fermentation.

• 한국버섯학회지
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• 제4권3호
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• pp.122-127
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• 2006

4가지 물질의 분말을 10배액, 100배액, 500배액, 1000배액, 1500배액, 2000배액을 농도별로 처리하여 목이버섯 균사생장과 균사밀도를 조사한 결과는 다음과 같다. Senna은 대조구에 비하여 10배액, 100배액, 500배액, 1000배액, 1500배액 2000배액의 6가지 처리 모두가 균사생장과 밀도가 좋았으며 그중 100배액이 가장 좋았다. L-citrulline 분말은 처리농도 500배액이 대조구에 비해 같은 기간 내에 7.86mm/15일이 더 빨리 자랐으며 균사밀도도 좋아 최적 희석배수를 나타내었다. L-carnitine 분말은 100배액은 대조구에 비해 균사생장이 3.4 mm/15일로 촉진되었으며 균사밀도도 촉진되었다. Garcinia cambogia 분말은 대조구에 비해 6가지 희석배수 모두 균사생장이 억제되는 경향을 나타내었다. 10배액의 가장 진한 희석배수에서 가장 균사생장이 억제되었고 1000배액은 거의 대 조구와 비슷한 경향을 나타내었다. 따라서 L-citrulline, L-carnitine, Senna, Garcinia cambogia 순으로 균사생장과 균사밀도에 촉진적으로 작용하였다.

• BMB Reports
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• 제28권4호
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• pp.301-305
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• 1995

Considering the stimulatory effects of ginsenosides from Panax ginseng C. A. Meyer on the release of nitric oxide from bovine aortic endothelial cells in vitro and vasodilatation of rabbit pulmonary artery in vivo, the present study is designed to investigate the mechanism of nitric oxide release by ginsenosides in calf pulmonary artery endothelial cells, Nitric oxide release was determined in endothelial cells treated with ginsenosides and compared with those of the receptor-dependent agonists, bradykinin and ADP and the receptor-independent calcium ionophore $A_{23187}$. The results showed that total saponin and ginsenoside $Rg_1$, not $Rb_1$, stimulated nitric oxide release measured as conversion to L-citrulline. The nitric oxide releasing properties of total saponin and ginsenoside $Rg_1$ were different; total saponin stimulated only conversion to L-citrulline, like $A_{23187}$, while ginsenoside $Rg_1$ stimulated both L-arginine transport and conversion to L-citrulline, as bradykinin or ADP did.

• 약학회지
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• 제49권6호
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• pp.465-470
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• 2005

Octacosanol is known to enhance endurance activities, control cholesterol in body and improve the function of cardiopulmonary. Citrulline, which is main compound of watermelon, is known to improve angiectasia through stimulating production of nitric oxide. To improve endurance activity swimming test on rats was carried out using four samples such as 1$\%$ octacosanol, citrulline, the extracts of barks of watermelon and products, mixture of 1$\%$ octacosanol and the extracts of barks of watermelon (6 : 4). Biochemical assays on the liver and serum of tested rats were also performed using commercial analysis kits. In result, it was shown that swimming time of III group increased by 26$\%$ and that of V group was increased by 22$\%$ at the swimming test. As a result of biological assays on the liver and serum of tested rats it was possible to confirm stability of toxicity When compared with creatine kinase of control group (549.11$\pm$39.15 U/l) citrulline (644.11 $\pm$50.67 U/l) and products group (646.00$\pm$46.99 U/l) were largely increased. When compared with inorganic phosphate of control group (12.01$\pm$0.75 mg/이), citrulline (13.03$\pm$0.94 mg/dl) and products group (12.90$\pm$0.55 mg/dl) showed similar results. Also, when compared with lactic acid and glucose of control group (152.91 $\pm$ 13.45, 103.00$\pm$ 8.69 mg/dl), citrulline (125.53$\pm$15.54, 83.75$\pm$7.29 mg/dl) and products group (135.26$\pm$11.50, 78.57$\pm$9.79 mg/dl) were largely decreased. As these test results, it was determined that 1$\%$ octacosanol and extracts of barks of watermelon had some effect of improving endurance activity. Futhermore, it was thought that it could be used as source of functional food.

• Journal of Microbiology and Biotechnology
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• 제4권2호
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• pp.95-101
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• 1994

The effects of glycine on cell growth and L-omithine production were investigated in shake-flask and jar fermentor cultures of a citrulline auxotrophic mutant, Brevibacterium ketoglutamicum BK 1046. In the shake-flask culture, the optimal concentration of glycine for L-ornithine production was found to be 20 g/l. In the jar fermentor culture with the glycine at an initial concentration of 20 g/l, L-ornithine production increased by 28%, compared to that of the culture with no glycine added. 37 g/l of L-ornithine was produced when additional feeding of glycine (5 g/l) was made. This was a significant improvement in L-ornithine production compared to that (ca. 24 g/l) of the corresponding batch culture conducted without glycine. According to the stoichiometric analysis with the batch fermentation results, the experimental and theoretical L-ornithine yields based on the glucose consumption were 0.24 and 0.59, respectively. This indicates that the performance of L-ornithine fermentation can further be improved by the supplementation of glycine and the development of a mutant strain possessing a higher growth yield.

• 한국임상수의학회지
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• 제2권1호
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• pp.105-114
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• 1985

The optimal conditions for the evaluation of serum ornithine carbamyltransferase activity, based on the do-termination of citrulline formed during the enzymatic reaction, were investigated and the serum ornithine carbamyltransferase activity of cattle were surveyed. Barbital-acetate buffer(70m moles/L, pH 7.0 at $37^{\circ}C$) were usea for the entire experiment. The results were as follows. 1. When the concentration of $H_2SO_4$ in color reagent exceeds 3.0 m1/100m1 the serum protein precipitated and absorbance increased. 2. The concentrations of antipyrine and diacetylmonoxime required for maximal color formation were 1g/L and 5g/L, respectively. 3. The absorbance was maximal when the reaction mixture was boiled for 25 minutes. 4. The chromogen were stable for at least 60 minutes under loon lighting condition, but decolorized rapidly under direct sunlight. 5. The minimal concentration of urease solution(Sigma Chemical Co., Type III) required for elimination of serum urea was 0, 6mg/ml. 6. When the concentration of L-ornithine solution increased up to 22m moles/L, the ornithine carbamyltransferase activity was not inhibited by zwitterion of ornithine. 7. In accordance with the increase of carbamylphosphate concentration the ornithine carbamyltransferase activity increased and the nonenzymatic citrulline production also increased slightly. 8. The standard curve of citrulline revealed linear pattern within the range of this experiment (0.1~4.0m moles/L). 9. The ornithine carbamyltransferase activities of normal cattle investigated in this laboratory were 6.85$\pm$4.38U/L (mean$\pm$SD) in cows and 2.89$\pm$2.50U/L in bulls. The range of the activities were 0.39～29.12U/L in cows and 0.06~17.34U/L in bulls.

• Neonatal Medicine
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• 제17권2호
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• pp.250-253
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• 2010

Citrullinemia는 요소 회로 이상으로 argininosuccinate synthetase의 결핍으로 기인한다. 저자들은 citrullinemia type I 환자와 그의 가족에서 새롭게 발견된 돌연변이를 경험하여 이를 보고하고자 한다. 환아는 광범위 신생아 선천성 대사이상 선별검사에서 citrulline이 고도의 증가 소견과 혈청 암모니아는 $982{\mu}mol/L$까지 증가 소견을 보였다. 혈청 아미노산 분석결과 citrulline 1,581 nmol/mL로 현저한 증가 소견을 보였으며 또한 소변 유기산 분석 검사결과 orotic acid가 3,566 mmol/mol Cr로 매우 증가된 소견을 보였다. Citrullinemia 확진을 위하여 환아와 가족에 대하여 ASS1 gene 검사를 시행하였다. 환아는 c.689G>C (p.G230A)와 c.892G>A (p.E298k)의 변이가 발견되어 ASS1 gene의 돌연변이에 의한 citrullinemia type I 으로 진단되었으며, 두 가지 돌연변이는 아직 국내에 보고된 적 없는 새로운 것으로 확인되었다. 국내에서 새롭게 발견된 citrullinemia type I 유전자를 보고하며 citrullinemia를 보인 경우 확진 및 유전상담을 위하여 가족 유전자 검사를 시행하는 것이 필요하다고 생각한다.

• Archives of Pharmacal Research
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• 제18권6호
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• pp.434-439
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• 1995

In pancreatic cells, NO formation is associated with increased levels of cGMP and endocrine/exocrine secretion. In the present study, the role of NO in the regulation of exocrine secretion was investigated in rat pancreatic tissues. Treatment of rat pancreatic tissue with sholecystokinin-pancreozymin (CCK-PZ) resulted in an significant increase in arginine conversion to citruline, the amount of nitrite/nitrate, the release of amylase, and the level of cGMP. Furthermore, CCK-PZ stimulated increase of amylase release and conversion of arginine to citrulline transformation were counteracted by the inhibitor of NO synthase, $N^G-nitro-L-arginine$ methyl ester. The results on the time course of CCK-PZ-induced citrulline formation within the first seconds of simulation. The kinetics of citrulline accumulation correlate well with those of cGMP rise, which further confirms the conclusion that NO mediates the response to CCK-PZ by cGMP.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.657-663
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• 1998

The enzyme responsible for the synthesis of nitric oxide (NO) from L-arginine in mammalian tissues is known as nitric oxide synthase (NOS) (EC.1.14.13.39). In the present study, the role of NO in the regulation of exocrine secretion was investigated in rat pancreatic acinar cells. Treatment of rat pancreatic acinar cells with cholecystokinin-octapeptide (CCK-OP) resulted in an increase in the arginine conversion to citrulline, the amount of $NO_X$, the release of amylase, and the level of CGMP. Especially, CCK-OP-stimulated increase of arginine to citrulline transformation, the amount of $NO_X$, and CGMP level were completely counteracted by the inhibitor of NOS, NG-monomethyl-L-arginine (MMA), by contrast, that of amylase release was partially reduced. Furthermore, MMA-induced decrease of NOS activity and amylase release showed dose-dependent pattern. The data on the time course of CCK-OP-induced citrulline formation and CGMP rise indicate that NOS and guanylate cyclase were activated by treatment of CCK-OP. However, the mechanism of agonist-stimulated guanylate cyclase activation in acinar cells remains unknown. Therefore, activation of NOS is one of the early events in receptor-mediated cascade of reactions in pancreatic acinar cells and NO, not completely, but partially mediate pancreatic enzyme exocrine secretion.