Cystinuria: A rare cause of bladder stone

VCystinuria is an inherited metabolic disorder progressing with recurrent kidney stones due to impaired reabsorption of dibasic amino acids and arises from mutations in the SLC3A1 and SLC7A9 on chromosome 2. Here, we present the case of a 1-year 10-month-old male child with recurrent episodes of urinary tract infections. On evaluation, duplex kidneys and a large bladder calculus were found which was surgically managed. Stone analysis and the genetic study were suggestive of cystinuria.

Medical nutrition management and follow-up of patients with late-onset ornithine transcarbamylase deficiency / 中华实用儿科临床杂志

Objective:To explore the clinical characteristics and medical nutritional therapy of 6 patients with late-onset ornithine transcarbamylase (OTC) deficiency.Methods:The clinical features, biochemical data, gene variations and treatment outcomes of 6 children with late-onset OTC deficiency admitted to the Department of Clinical Nutrition, Children′s Hospital of Nanjing Medical University from January 2020 to April 2022 were retrospectively analyzed.The 6 patients were all intervened by a long-term medical nutrition management.Results:Liver dysfunction and hyperammonemia (172.1-348.0 μmol/L) were found in all the 6 children with late-onset OTC deficiency.Serum citrulline decreased in 3 patients (3.95-5.43 μmol/L). Three patients showed increased urine orotic acid (123.48-342.60 mmol/mol Cr). Urine uracil increased in 4 patients (106.77-1 207.26 mmol/mol Cr). Variations of the OTC gene [c.364G>C p. (E122Q), c.1028C>G p. (T343R), c.664-2(IVS6)A>C, c.635G>T p. (G212V), c.929_c.931delAAG p. (E310del), c.829C>T p. (R277W)] were identified in all patients.The 6 children were all managed by individualized medical nutrition program and followed up for a long time.During the follow-up period, 3 cases developed hypoproteinemia, acute metabolic crisis and growth retardation, 3 cases had normal growth and laboratory indicators, and 1 case received liver transplantation after 3 months of nutritional management. Conclusions:The clinical manifestations of OTC deficiency are non-specific.Blood amino acids, urine organic acids and genetic tests are important for the diagnosis.Long-term regular medical nutrition management is helpful to improve the prognosis and quality of life of children.

Newborn screening for ornithine transcarbamylase deficiency in Zhejiang Province and the follow-up analysis / 中华实用儿科临床杂志

Objective:To investigate the incidence, clinical characteristics and prognosis of ornithine transcarbamylase deficiency(OCTD) in newborns in Zhejiang Province.Methods:A retrospective research was conducted.A total of 4 261 036 newborns from Department of Genetics and Metabolism, Children′s Hospital, Zhejiang University School of Medicine, between January 2009 and December 2021 were screened for inherited metabolic disorders using tandem mass spectrometry.OCTD was confirmed by urine organic acid and OTC gene analysis.Patients with OTCD received guidance on diet and lifestyle management, and were treated with citrulline and arginine.Long-term follow-up was performed.Their growth and intellectual development were evaluated. Results:A total of 7 patients with OCTD were diagnosed, with an incidence of 1.6/1 million.All patients were males.Two patients had neonatal-onset OCTD, and the other 5 had late-onset OCTD.Symptoms occurred several times in 6 patients, inducing hyperammonemia and hepatic impairment.One patient had no clinical manifestation.One patient died in the neonatal period.Blood citrulline levels were decreased in 7 patients to varying degrees.Uracil levels were increased in 4 patients, and 1 of them was complicated with elevated orotic acid levels.All patients had hemizygote variations in the OTC gene, including 6 missense variations(c.604C>T, c.386G>A, c.779T>C, c.1019C>T, c.594C>G, c.931G>A) and 1 intron variation(c.514-35C>G). Two variants(c.594C>G, c.514-35C>G) were never reported previously. Conclusions:The OTCD incidence by newborn screening is low with 1.6/1 million in Zhejiang province.All patients are males and present hypocitrullinemia.The clinical manifestations of OTCD are highly heterogeneous.The neonatal-onset form is severe and survivors always suffer serious sequelae.The late-onset form is mostly manifested with hyperammonemia and hepatic impairment.There may be association between phenotype and genotype.Two novel OTC variants are identified, which further expands the mutational spectrum.

Neonate-onset ornithine transcarbamylase deficiency / 中国当代儿科杂志

The male neonate in this case study was admitted to the hospital at 15 hours of age due to respiratory distress for 15 hours and poor response for 3 hours after resuscitation from asphyxia. The neonate was highly unresponsive, with central respiratory failure and seizures. Serum ammonia was elevated (>1 000 μmol/L). Blood tandem mass spectrometry revealed a significant decrease in citrulline. Rapid familial whole genome sequencing revealed OTC gene mutations inherited from the mother. Continuous hemodialysis filtration and other treatments were given. Neurological assessment was performed by cranial magnetic resonance imaging and electroencephalogram. The neonate was diagnosed with ornithine transcarbamylase deficiency combined with brain injury. He died at 6 days of age after withdrawing care. This article focuses on the differential diagnosis of neonatal hyperammonemia and introduces the multidisciplinary management of inborn error of metabolism.

Treatment and management for children with urea cycle disorder in chronic stage / 浙江大学学报·医学版

Urea cycle disorder (UCD) is a group of inherited metabolic diseases with high disability or fatality rate, which need long-term drug treatment and diet management. Except those with Citrin deficiency or liver transplantation, all pediatric patients require lifelong low protein diet with safe levels of protein intake and adequate energy and lipids supply for their corresponding age; supplementing essential amino acids and protein-free milk are also needed if necessary. The drugs for long-term use include nitrogen scavengers (sodium benzoate, sodium phenylbutyrate, glycerol phenylbutyrate), urea cycle activation/substrate supplementation agents (N-carbamylglutamate, arginine, citrulline), etc. Liver transplantation is recommended for pediatric patients not responding to standard diet and drug treatment, and those with severe progressive liver disease and/or recurrent metabolic decompensations. Gene therapy, stem cell therapy, enzyme therapy and other novel technologies may offer options for treatment in UCD patients. The regular biochemical assessments like blood ammonia, liver function and plasma amino acid profile are needed, and physical growth, intellectual development, nutritional intake should be also evaluated for adjusting treatment in time.

miRNA-6516-5p regulates the proliferation and migration of renal cancer cells by targeting ODC1 / 国际外科学杂志

Objective:To explore the expression of microRNA (miRNA)-6516-5p in renal cancer cell lines and the molecular mechanisms regulating the proliferation and migration of renal cancer cells.Methods:quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-6516-5p in renal cancer cell lines and normal proximal renal tubular epithelial cell lines. The liposome method was used to transiently transfect miR-6516-5p mimic and nonsense sequence (NC) into renal cancer cells with the lowest expression of miR-6516-5p, namely miR-6516-5p group and NC group. qRT-PCR was used to detect the expression of miR-6516-5p in transfected cells. CCK-8 and Transwell migration experiment were used to detect the proliferation and migration of transfected cells. Bioinformatics software and dual luciferase gene report experiment were used to predict and verify the regulation of miR-6516-5p on target gene, respectively. qRT-PCR and Western blotting were used to detect the expression of target gene in transfected cells. Measurement data were expressed as mean±standard deviation ( ± s), t-test was used for comparison between two groups, and one-way analysis of variance was used for comparison between multiple groups. Results:The expression of miR-6516-5p in renal cancer cell lines was significantly lower than that of normal proximal tubular epithelial cells ( P<0.01), and the expression of miR-6516-5p in 786-O cells was the lowest ( F=27.69, P<0.01). The expression of miR-6516-5p in 786-O cells in NC group and miR-6516-5p group was 1.01±0.08 and 9.91±1.16, respectively. Compared with the NC group, the expression of miR-6516-5p in 786-O cells in the miR-6516-5p group was significantly increased ( t=7.63, P<0.01). Up-regulation of miR-6516-5p can significantly inhibit the proliferation of 786-O cells ( P<0.05). The migration numbers of NC group and miR-6516-5p group were 85.65±8.77 and 28.05±6.20, respectively. Overexpression of miR-6516-5p could inhibit the migration of 786-O cells ( t=5.36, P< 0.01). The target gene of miR-6516-5p may be ornithine decarboxylase 1 ( ODC1), miR-6516-5p can significantly inhibit the luciferase activity of wild-type ODC1-3′UTR ( t=9.83, P<0.01). Up-regulation of miR-6516-5p can reduce the expression of ODC1 mRNA and protein in 786-O cells ( P<0.01). Conclusion:The expression of miR-6516-5p is reduced in renal cancer cell lines, miR-6516-5p inhibits the proliferation and migration of renal cancer 786-O cells by targeting ODC1, miR-6516-5p may become a potential molecular target of renal cancer.

Novel gene mutation and clinical features in a family with gyrate atrophy of choroid and retina / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the pathogenic mutations of the <i>OAT</i> gene in a Chinese family affected with gyrate atrophy of choroid and retina(GA)and describe their clinical manifestations.METHODS: All available family members have underwent detailed ophthalmological examinations. The sequencing results and pathogenic mutations were clarified by whole exome sequencing, bioinformatics analysis and Sanger sequencing.RESULTS: Based on the clinical manifestations and symptoms, the proband was diagnosed with GA. A missense mutation of c.722C>T(p.P241L)in exon 6 and a nonsense mutation of c.1186C>T(p.R396X)in exon 10 were identified in the <i>OAT</i> gene of the proband, which was a compound heterozygotic mutation. This compound heterozygous mutation showed co-segregation in the family. The heterozygous pathogenic variant of p.R396X was detected in both the proband's father and elder brother, and the heterozygous pathogenic variant of p.P241L was detected in proband's mother. Except for the proband, no other family members have abnormal clinical manifestations.CONCLUSION: The proband of this family is a compound heterozygous mutation, in which p.P241L is the first reported gene mutation type. This result expands the range of <i>OAT</i> gene variation and is conducive to further understanding the pathogenic factors of GA at the molecular basis level. The discovery and confirmation of the novel mutation type will also help to provide a new basis for the clinical diagnosis and gene therapy of GA.

Analysis of the Key Metabolites and Genes Involving in Ornithine-Urea Cycle in Mytilus coruscus / 中国生物化学与分子生物学报

The ornithine-urea cycle (OUC) plays important roles in metabolism. However, there is a lack of study of OUC in shellfish. For filling this gap, the mussel Mytilus coruscus was selected, and the key genes together with the metabolites of OUC pathway were analyzed in the mantle and adductor muscle, respectively, using a real-time fluorescent quantitative PCR and an amino-acid analyzer. Moreover, the changes of the metabolite concentrations and the gene relative expression level of OUC were analyzed after arginine injection. The δ

Optimization of a cucurbit6uril-based real-time label-free method for analyzing the activity of ornithine decarboxylase / 生物工程学报

Ornithine decarboxylase (ODC) is a key enzyme in the biosynthetic pathway of polyamines and catalyzes the decarboxylation of ornithine to produce putrescine. Inhibition of ODC activity is a potential approach for the prevention and treatment of many diseases including cancer, as the expression levels and the activities of ODC in many abnormal cells and tumor cells are generally higher than those of normal cells. The discovery and evaluation of ODC inhibitors rely on the monitoring of the reaction processes catalyzed by ODC. There are several commonly used methods for analyzing the activity of ODC, such as measuring the yield of putrescine by high performance liquid chromatography, or quantifying the yield of isotope labelled carbon dioxide. However, the cumbersome operation and cost of these assays, as well as the difficulty to achieve high-throughput and real-time detection, hampered their applications. In this work, we optimized a real-time label-free method for analyzing the activity of ODC based on the macromolecule cucurbit[6]uril (CB6) and a fluorescent dye, DSMI (trans-4-[4-(dimethylamino) styryl]-1-methylpyridinium iodide). Finally, the optimized method was used to determine the activities of different ODC inhibitors with different inhibition mechanisms.

Exploring Biodiversity for Prevention and Control of Cancer and other Non-Communicable Diseases using Indigenous Environmental Resources: An Interdisciplinary Research

Background: An interdisciplinary research of public health, biomedical and pharmaceutical sciences is neededfor integrating qualitative and quantitative researches undertaken. It hence requires focus on public beneficencefor non-communicable diseases. Purpose: To study anticancer activities of soil samples of Central India andits stability for applied public health use. Material and Methods: Screening on Actinomycetes isolates obtainedfrom rural and urban farm soils illustrating arginase production was conducted from equated soil samples ofgeo-representative localities and adjoining areas of Bhopal, India. Enrichment Technique (CDSEA) was usedfor detection of extracellular production of L-arginase and their anticancer activities using MTT 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay along with characterization and probioticproperties of selected isolate. Results: L-Arginase activity quantified by ornithine (21.06-117.92 U/mg) wasfound in isolates BRD-21, KAR-73, BHA-162, BAR-199, ARH-210, HAB-228. Urea release (15.88 – 59.79 U/mg protein) depicted L- arginase activity in crude enzyme samples. It shows noticeable anticancer activity.Morphological and biochemical characterization of these isolates revealed metabolic diversity. Isolate KAR 73produced collagenase (specific activity 57.8 U/mg), L-asparaginase (specific activity 116 U/mg) and L-arginasewith tolerance to higher temperature (45°C) and salt concentration (2-8% w/v). Equal concentrations ofcrude L- arginase from these isolates inhibited growth and proliferation of colorectal adenocarcinoma celllines (19.99%-38.65%) under in-vitro conditions. Conclusion: Arginine depletion through arginase activity isevidenced for potential effectiveness in cancer treatment especially adenocarcinomas and squamous cellcarcinoma. It is useful for wider public health purposes

A novel splice site mutation in OTC gene of a female with ornithine transcarbamylase deficiency and her asymptomatic mosaic father

Ornithine transcarbamylase deficiency is an X-linked disease with a wide range of clinical severity and manifestation age both in males and females. Here, we describe a case which is caused by a novel c.78-1G[A splice site mutation, which on mRNA level leads to a 1-bp deletion and a frameshift (c.78delG (p.C27Vfs*11)) in OTC exon 2 in a young girl. The same mutation has been detected in a mosaic state in her asymptomatic father.

Regression of macular edema with topical brinzolamide and nepafenac alone and identification of a novel gyrate atrophy mutation / Regressão de edema macular com o uso tópico de brinzolamida e nepafenac e identificação de uma nova mutação na atrofia girata

ABSTRACT Gyrate atrophy is a rare metabolic autosomal recessive disorder caused by ornithine aminotransferase enzyme deficiency that leads to characteristic progressive, degenerative chorioretinal findings. Patients complain mostly of low vision, night blindness, and peripheral vision loss. Posterior subcapsular cataract, myopia, choroid neovascularization, and intraretinal cysts may be accompanying factors related to vision loss. We encountered a patient with vision loss secondary to posterior subcapsular cataract and intraretinal cysts. After treatment with topical brinzolamide and nepafenac (and without any diet mo dification and/or supplementation), we observed 143- and 117-mm macular thickness resolutions with 2 and 1 Snellen lines of visual gain in his right and left eyes, respectively. Also, we detected a novel homozygous mutation in the ornithine aminotransferase gene: c.1253T>C (p.Leu418Pro). Carbonic anhydrase inhibitors and/or non-steroid anti-inflammatory drugs can control macular edema in patients with gyrate atrophy-associated intraretinal cysts. The genetic variants may also be a determinant in the responsiveness to the therapy type.

RESUMO A atrofia girata é um distúrbio autossômico recessivo metabólico raro causado pela deficiência da enzima ornitina ami notransferase, que leva a achados degenerativos coriorretinianos progressivos característicos. Os pacientes queixam-se principalmente de baixa visão, cegueira noturna e perda de vi são periférica. A catarata subcapsular posterior, a miopia, a neovascularização da coróide e os cistos intrarretinianos podem ser fatores associados à perda da visão. Encontramos um paciente com perda de visão secundária à catarata subcapsular posterior e cistos intrarretinianos. Após o tratamento com brinzolamida tópica e nepafenaco (e sem modificação e/ou suplementação da dieta), observamos resoluções de espessura macular de 143 e 117 mm e com 2 e 1 linhas de Snellen de ganho visual nos olhos direito e esquerdo, respectivamente. Além disso, detectamos uma nova mutação homozigótica no gene da ornitina aminotransfera se: c.1253T>C (p.Leu418Pro). Inibidores da anidrase carbônica e/ou drogas anti-inflamatórias não esteróides podem controlar o edema macular em pacientes com cistos intrarretinianos associados à atrofia girata. As variantes genéticas também podem ser determinantes na responsividade ao tipo de terapia.

Consensus on diagnosis and treatment of ornithine trans-carbamylase deficiency / 浙江大学学报·医学版

Ornithine transcarbamylase deficiency(OTCD)is a most common ornithine cycle (urea cycle) disorder. It is a X-link inherited disorder caused by

Research on anti-non-small cell lung cancer activity of ornithine decarboxylase anti-enzyme inhibitor-1 small molecule inhibitor / 中国药理学通报

Aim To investigate the inhibitory effect of small molecule inhibitors of ornithine decarboxylase inhibitor 1 (AZIN-1) on non-small cell lung cancer and its mechanism. Methods Cell proliferation was detected by Cell Counting Kit-8 (CCK-8). Apoptosis was analyzed by flow cytometry (PI/Annexin V-FITC double staining). The expression of ornithine decarboxylase (ODC), ornithine decarboxylase anti-enzyme-1 (AZ-1) and AZIN-1 was detected by Western blot. Cell cycle was analyzed by flow cytometry (PI single staining). The total polyamine content in cellswas measured by high performance liquid chromatography (HPLC). Results Small molecule inhibitor of AZIN-1 could significantly inhibit the proliferation of A549 cells, cause G0/G, cycle arrest, induce apoptosis of A549 cells, inhibit the expression of AZIN-1 and ODC, interfere with intracellular polyamine metabolism, and reduce total polyamine content in cells. Conclusions Small molecule inhibitor of AZIN-1 has significant growth inhibitory effect on A549 cells, and its mechanism may be related to the induction of apoptosis and interference with polyamine metabolism.

A healthy neonate born at the third pregnancy of a woman with ornithine carbamoyltransferase deficiency under multidisciplinary management / 中华围产医学杂志

We reported a women with omithine carbamoyltransferase deficiency who delivered a healthy boy after two pregnancies with adverse outcome with the help of a multidiscipline team.The woman was admitted to Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine with an acute prenatal hyperammonemic episode at 28 gestational weeks of her first pregnancy in 2013 and was diagnosed with ornithine transcarbamylase deficiency.Her hyperammonemic complications were controlled under a well-planned multidisciplinary management including a low-protein diet and appropriate medications assisting nitrogen removal.A boy was delivered by cesarean section at 32 weeks of gestation but died three days later.Mutation analysis revealed a hemizygous c.583G＞A (G195R) mutation in the neonatal omithine carbamyltransferase gene and his mother was a heterozygous carrier with the same mutation.Two years later in 2015,the patient was pregnant spontaneously.However,she received an induced abortion at 21 weeks of gestation because amniocentesis and DNA analysis showed that the male fetus had the same omithine transcarbamylase gene mutation.The index pregnancy was assisted by in vitro fertilization-embryo transfer and preimplantation genetic diagnosis in 2017 and the woman delivered a healthy boy with the management ofa multidisciplinary team.

Predictable factors for intervention with heparin free plasmapheresis in impending liver cell failure due to consumption of phosphorus rodenticide

Background: Yellow phosphorus containing rodenticide poisoning are common in Adult critical care. They cause coagulopathy and liver cell failure in humans. Till date, only liver transplants had been advocated as the final treatment of fulminant liver failure occurring as a complication of rodenticide poisoning. In this study, an innovative Treatment approach was given to liver cell failure cases who had consumed yellow phosphorus paste.Methods: Retrospective analysis of case records of liver cell failure cases due to the consumption of phosphorus containing Rodenticide poisonings, were analysed for a period of 1 year from January 2018 to January 2019 in a public hospital. Medical case records were obtained from records department and Postmortem registers. Symptoms, signs, investigations, treatments, complications, and outcomes were tabulated.Results: Total 11 cases were studied. 8 cases of liver cell failure and coagulopathy in whom therapeutic heparin free plasmapheresis was given, recovered completely from liver cell failure. A significant drop in Haemoglobin, platelet count, PT INR Ratio and rise in serum alkaline phosphatase, were the predictable factors used for the intervention of therapy with 5 cycles of heparin free plasmapheresis to eliminate toxic effects of phosphorus on liver cells and in the blood. A comparative analysis of untreated cases (n=3) vs treated with plasmapheresis (n=8), showed a significant statistical difference (P <0.005) in outcomes with a degree of freedom=2.Conclusions: Plasmapheresis can be a therapeutic treatment for liver cell failure caused due to the consumption of yellow phosphorus.  Predictable factors for impending liver cell failure in whom plasmapheresis will be of benefit are dependent upon prothrombin time, INR ratio, Liver enzymes and time interval between consumption and onset of liver cell failure.

Clinical research of two cases of late-onset ornithine carbamoyltransferase deficiency / 中华神经科杂志

Objective To explore the clinical characteristics of late-onset ornithine carbamoyltransferase deficiency (OTCD) in order to improve the clinicians' understanding of this disease.Methods The clinical,therapeutic and follow-up data of two patients with late-onset OTCD diagnosed in the Department of Neurology,Qilu Hospital of Shandong University from November 2017 to February 2018 were collected and analyzed.Results Case 1 is a 17-year-old male who was admitted into Qilu Hospital with recurrent dizziness and vomiting for 4 months,sudden mental abnormality and convulsion for 3 days.The liver dysfunction,respiratory alkalosis and hyperammonemia (434 μmol/L) had been found before his admission.His blood ammonia fluctuated obviously from 180 μ mol/L to 2998 μmol/L,though he was given hemodialysis and arginine infusion,and died on the fourth day after admission.Case 2 is a 15-year-old male,complained with recurrent dizziness,vomiting,bluntness and somnolence for 20 days.He was found with hyperammonemia (600 μmol/L) and liver dsyfunction in a local hospital.He was getting better after intravenous administration of arginine and liver protective drugs.After admission,the blood ammonia,liver function and amino acids,acylcarnitine profiling in dried blood spots,and organic acid analysis in urine were normal,and he has not recurred since restriction of protein diet.Brain magnetic resonane imaging of both patients showed cytotoxic edema of bilateral frontal lobe and insular cortex,and their genetic detection both showed c.119G＞A(p.R40H) hemizygous pathogenic mutation of OTC gene inherited from their respective mothers.Conclusion Unexplained hyperammonemia and acute encephalopathy with insular and frontal cortical involvement should be on the alert to the urea cycle disorders,especially OTCD.Early diagnosis and reasonable treatment are the key to changing the prognosis.

Enzymatic production of arginine derivatives: a review / 生物工程学报

L-arginine (L-Arg) is an alkaline amino acid that possesses various function groups and acts as an important precursor for useful chemical synthesis. L-Arg derivatives are widely applied in pharmaceutical, food and cosmetic industries. Environment friendly and cost-effective production of L-Arg derivatives by enzymatic catalysis provides significant advantages over chemical synthesis and microbial fermentation. In this article, several typical L-Arg derivatives and their enzymatic production processes are highlighted. Furthermore, prospect is also addressed about enzymatic production of L-Arg derivatives.

siRNA-mediated antizyme inhibitor down-regulates the expression of ornithine decarboxylase of prostate cancer cell PC3 / 基础医学与临床

Objective To evaluate whether down-regulating antizyme inhibitor(AZIN) can regulate the expression of ornithine decarboxylase(ODC) and the proliferation of prostate cancer cell PC3 or not.Methods siRNA-AZIN transfected prostate cancer cell PC3,the level of antizyme(AZ),AZIN and ODC were measured by RT-PCR and westernblot. MTT was used to measure the proliferation of cells. Results The mRNA level of AZIN declined(P<0.01);the protein level of AZIN and ODC declined(P<0.05). Knockdown of AZIN significantly inhibited the proliferation of PC3(P<0.05). Conclusions Transfecting siRNA-AZIN can decrease the level of AZIN, then the decline level of ODC inhibits the proliferation of PC3.

Studies on the Acute Toxicity in Mice and Cytotoxicity of the Impurity in Ornithine / 中国药师

Objective:To study the acute toxicity in mice and cytotoxicity of the impuritiy(3-amino-2-piperidinone hydrochloride) in ornithine. Methods:The mice were given the impurity by intravenous injection.The acute toxicity was observed and LD50in mice was calculated by Bliss method. According to the result of LD50,the mice were given the impurity respectively at high,medium and low dose. The changes of general condition and body weight were recorded,and the blood biochemical indices and histomorphology of organs and tissues were observed after 14 days. The cytotoxicity was measured on fibroblasts(L929) cells. Results:The LD50and 95% con-fidence limit of the impurity (intragastric administration) was 758.49-848.08 mg·kg-1.All the detected indices of the three groups (660,330 and 170 mg·kg-1) including general condition,weight change,biochemical indices,organ morphological and histological change were all within the normal ranges. The impurity significantly decreased the viability of L929 cells. The NOAEL value was 660 mg·kg-1in mice. Conclusion:The impurity has certain toxicity to mice and cells. The data can provide experimental basis for the quality standard establishment for ornithine and the safety improvement in clinic use.