Animals ; Arginine Vasopressin ; metabolism ; Female ; Hippocampus ; drug effects ; metabolism ; Lead ; toxicity ; Learning ; drug effects ; Memory ; drug effects ; Pregnancy ; Prenatal Exposure Delayed Effects ; Rats ; Rats, Sprague-Dawley

PURPOSE: The effects of amiloride on cellular toxicity caused by tissue plasminogen activator (tPA) in mouse primary retinal cells were investigated. METHODS: Primary retinal cell cultures were maintained using glial conditioned medium. Commercial tPA and L-arginine were added, and the level of cyclic guanosine monophosphate (cyclic-GMP) in the culture supernatant was assessed using an ELISA assay. We measured the cell viability of cultured retinal cells pretreated with three different concentrations of amiloride (1, 10, and 100 microm) in addition to commercial tPA or L-arginine treatment. RESULTS: After exposing the cultured mouse retinal cells to tPA plus L-arginine or L-arginine alone, cyclic-GMP concentrations were 61.9 +/- 5.1 pmole/mL and 63.1 +/- 6.1 pmole/mL, respectively. However, the control group had a significantly lower concentration of cyclic-GMP (37.2 +/- 3.4 pmole/mL, p < 0.01). The cyclic GMP-dissolved solution did not cause retinal cell death. In the control group and the group treated with 1 microm amiloride and tPA containing L-arginine, the cell viability was 43.7% and 44.5%, respectively. However, cell viability increased to 70.6% with 10 microm amiloride and 78.4% with 100 microm amiloride (p = 0.015). CONCLUSIONS: L-arginine increases intracellular cyclic-GMP and may give rise to retinal cells through this mechanism. In addition, amiloride in concentrations greater than 10 microm protects against L-arginine-induced retinal cell death.
Amiloride/*pharmacology ; Analysis of Variance ; Animals ; Arginine/toxicity ; Cell Death/drug effects ; Cells, Cultured ; Cyclic GMP/pharmacology ; Enzyme-Linked Immunosorbent Assay ; Mice ; Retina/cytology/*drug effects ; Tissue Plasminogen Activator/*toxicity

The expression of microRNA-19b (miR-19b) in acute necrotizing pancreatitis (ANP) and its functional role in acinar cell necrosis of SD rats were investigated. Twelve SD rats were divided into two groups randomly, including control group and ANP group. The rat ANP models were established by intraperitoneal injection of L-arginine (2400 mg/kg body weight), and equal volume of 0.9% NaCl was injected in the control group. MiRNA chip assay was performed to examine the expression of miRNAs in the pancreas in two different groups. Besides, to further explore the role of miR-19b in ANP in vitro, taurolithocholic acid 3-sulfate disodium salt (TLC-S) (200 μmol/L) was administrated to treat the rat pancreatic acinar cell line, AR42J, for establishing the ANP cells model. The quantitative real-time PCR (qRT-PCR) was adopted to measure the miR-19b expression. Moreover, the mimic miRNA, miRNA antisense oligonucleotide (AMO) and control vector were used to transfect AR42J cells, the expression of miR-19b was confirmed by qRT-PCR and the necrotizing rate of AR42J cells was detected with AO/EB method. The expression of miR-19b was significantly higher in ANP group than in control group as displayed by the miRNA chip assay. Furthermore, after inducing necrosis of AR42J cells in vitro, the expression of miR-19b was significantly increased by 2.51±0.14 times in comparison with the control group. As revealed by qRT-PCR assay, the expression of miR-19b was 5.94±0.95 times higher in the mimic miRNA group than in the control vector group, companied with an obviously increased acinar cell necrotizing rate (50.3%±1.5% vs. 39.6%±2.3%, P<0.05). Moreover, the expression of miR-19b in the miRNA AMO group was 0.38±0.15 times lower than in the control vector group, and the cell necrosis rate was much lower accordingly (23.1%±3.3% vs. 39.6%±2.3%, P<0.05). Besides, there was no significant difference between the control vector cells and the cells without treatment (P>0.05). The expression of miR-19b was significantly induced in ANP. In addition, up-regulation of miR-19b could promote the necrosis of pancreatic acinar cells and miR-19b deficiency could decrease the rate of pancreatic acinar cell necrosis.
Acinar Cells ; metabolism ; pathology ; Animals ; Arginine ; toxicity ; Cell Line ; MicroRNAs ; genetics ; metabolism ; Necrosis ; Pancreatitis, Acute Necrotizing ; etiology ; metabolism ; Rats ; Rats, Sprague-Dawley ; Taurolithocholic Acid ; analogs & derivatives ; toxicity ; Up-Regulation

BACKGROUND/AIMS: Upregulated CD64 expression on neutrophils is the most useful marker for acute bacterial infections and systemic inflammation. However, it is unknown whether CD64 is involved in the pathogenesis of acute pancreatitis (AP). This study was designed to determine whether CD64 is implicated in severe acute pancreatitis (SAP), and thus, is a suitable marker for SAP. METHODS: SAP was induced in rats with an intraperitoneal injection of L-arginine. CD64 expression in the rat pancreas was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Additionally, the CD64 mRNA expression in peripheral blood leukocytes from 21 patients with mild acute pancreatitis (MAP) and 10 patients with SAP was investigated at the time of admission and during remission by qRT-PCR. RESULTS: CD64 mRNA and protein expression in the pancreas was significantly higher in rats with SAP, compared to the controls. The CD64 expression was higher in the patients with SAP than in the patients with MAP. During remission, CD64 mRNA decreased in both the MAP and SAP patients. The area under the curve of CD64 expression for the detection of SAP was superior to both the Ranson and the Acute Physiology and Chronic Health Evaluation II scores. CONCLUSIONS: The CD64 level was significantly increased in correlation with the disease severity in SAP and may act as a useful marker for predicting the development of SAP.
Acute Disease ; Adolescent ; Adult ; Aged ; Animals ; Arginine/toxicity ; Female ; History, Ancient ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Pancreatitis/*metabolism ; RNA, Messenger/metabolism ; Rats, Sprague-Dawley ; Receptors, IgG/*metabolism ; Up-Regulation ; Young Adult

OBJECTIVETo evaluate the effects of Caulis Sinomenii and sinomenine on conditioned place preference (CPP) induced by morphine and brain histamine level in mice.

METHODSSixty mice were randomized into 6 equal groups and morphine (Mor) was injected subcutaneously (9 mg/kg) for 6 consecutive days to induce CPP using a shuttle box. Since the 4th day of training, the mice in 5 of the groups were treated for 3 consecutive days with Caulis Sinomenii (10 g/kg), sinomenine (60 mg/kg), diphenhydramine (30 mg/kg), CP48/80 (5 mg/kg) and L-histidine (750 mg/kg) in addition to morphine (9 mg/kg) treatment, respectively, leaving the other group with exclusive morphine treatment. Another 10 mice received saline injection to serve as saline control group. The content of histamine (HA) in the mouse brain was measured by fluorospectrophotometry.

RESULTSIn morphine group, the mice showed significantly extended stay in morphine-paired compartment whose HA content in the brain was markedly increased (P<0.01). Treatment with Caulis Sinomenii and sinomenine resulted in significantly reduced time of stay in morphine-paired compartment and brain HA level (P<0.01).

CONCLUSIONCPP induced by morphine in mice is associated with increased HA level in the brain. Caulis Sinomenii and sinomenine can suppress the acquisition of place preference induced by morphine and modulate HA level in the central nervous system in morphine-dependent mice.

Animals ; Arginine ; pharmacology ; Brain ; drug effects ; metabolism ; Conditioning, Operant ; drug effects ; physiology ; Diphenhydramine ; pharmacology ; Histamine ; metabolism ; Male ; Mice ; Morphinans ; pharmacology ; Morphine ; toxicity ; Morphine Dependence ; etiology ; physiopathology ; Motor Activity ; drug effects ; Random Allocation ; Sinomenium ; chemistry

The aim of the present study was to explore the effect of nitric oxide (NO) on iron-induced toxicity in rat hearts. Langendorff perfused rat heart and enzymatically isolated cardiomyocytes were used. It was shown that lipophilic Fe-HQ reduced the contractile amplitude, velocity and end-diastolic cell length in the cardiomyocyte, while the left ventricular developed pressure (LVDP), +/-dp/dt(max), heart rate and coronary flow showed biphasic alterations, which increased in the first 2 min and then was followed by a decline in isolated perfused rat heart; the contents of lactate dehydrogenase (LDH) and creatine kinase (CK) in the coronary effluent and the malondialdehyde (MDA) in the myocardium were increased. L-arginine (L-Arg), an NO precursor, reduced the contractile amplitude and end-diastolic cell length in the cardiomyocyte; but reversibly increased LVDP, +/-dp/dt(max), and coronary flow in isolated perfused rat heart. Pretreatment with L-Arg aggravated the Fe-HQ-induced decrease in contractile amplitude, velocity and end-diastolic cell length in the cardiomyocyte; LVDP, +/-dp/dt(max), heart rate and coronary flow were significantly reduced in the perfused heart, and the levels of LDH and CK increased in the coronary effluent. In contrast, the NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) blocked the Fe-HQ induced change in contractile amplitude, velocity and end-diastolic cell length in the cardio- myocyte; it inhibited the decrease in LVDP, LVEDP and +/-dp/dt(max), and reduced the LDH and CK. Removing endothelial cells in coronary vessels attenuated the increase in LVDP and +/-dp/dt(max) at the beginning of Fe-HQ perfusion. It is suggested that L-Arg aggravates the iron-induced cardiac dysfunction, NO can mediate the iron-induced toxicity in heart, and endothelial cells in coronary vessels play an important role in the early stage of the effect of iron.
Animals ; Arginine ; pharmacology ; Coronary Vessels ; cytology ; Creatine Kinase ; metabolism ; Endothelial Cells ; drug effects ; Heart ; drug effects ; Iron ; toxicity ; L-Lactate Dehydrogenase ; metabolism ; Malondialdehyde ; metabolism ; Myocardium ; metabolism ; Myocytes, Cardiac ; cytology ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide ; metabolism ; Rats

PURPOSE: To investigate the effect of advanced glycation end products (AGE) on oxidative stress and cellular senescence in cultured human trabecular meshwork cells (HTMC). METHODS: Primarily cultured HTMC were exposed to 0, 10, 50, 100, 200 microg/mL of glycated bovine serum albumin (G-BSA) for 5 days. Also co-exposed were L-arginine, sepiapterin, and antioxidant N-acetylcysteine (NAC). Cellular survival and production of nitric oxide (NO), superoxide, and reactive oxygen species were assessed by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide assay, Griess assay, cytochrome c assay, and dichlorofluorescin diacetate assay, respectively. Senescence-associated beta-galactosidase staining was performed to quantify the degree of cellular senescence. RESULTS: G-BSA decreased cellular survival, NO production, and increased superoxide production significantly in a dose-dependent manner. The effects of G-BSA were abolished with co-exposure of L-arginine, sepiapterin, and NAC. G-BSA enhanced cellular senescence accompanied by increased production of reactive oxygen species. G-BSA-induced cellular senescence was suppressed by application of L-arginine, sepiapterin, and NAC. CONCLUSIONS: AGE enhances cellular senescence of HTMC accompanied with increased oxidative stress. AGE-induced oxidative stress and cellular senescence could be delayed by application of anti-oxidants.
Acetylcysteine/metabolism ; Apoptosis/drug effects/physiology ; Arginine/metabolism ; Cell Aging/drug effects/*physiology ; Cell Survival/drug effects/physiology ; Cells, Cultured ; Glycosylation End Products, Advanced/metabolism/*toxicity ; Humans ; Nitric Oxide/metabolism ; Oxidative Stress/*physiology ; Pterins/metabolism ; Reactive Oxygen Species/metabolism ; Serum Albumin, Bovine/metabolism/toxicity ; Trabecular Meshwork/drug effects/*metabolism/*pathology

OBJECTIVETo compare the asbestos-induced DNA damage and repair capacities of DNA damage between 104 asbestos-exposed workers and 101 control workers in Qingdao City of China and to investigate the possible association between polymorphisms in codon 399 of XRCC1 and susceptibility to asbestosis.

METHODSDNA damage levels in peripheral blood lymphocytes were determined by comet assay, and XRCC1 genetic polymorphisms of DNA samples from 51 asbestosis cases and 53 non-asbestosis workers with a similar asbestos exposure history were analyzed by PCR/RFLP.

RESULTSThe basal comet scores (3.95 +/- 2.95) were significantly higher in asbestos-exposed workers than in control workers (0.10 +/- 0.28). After 1 h H2O2 stimulation, DNA damage of lymphocytes exhibited different increases. After a 4 h repair period, the comet scores were 50.98 +/- 19.53 in asbestos-exposed workers and 18.32 +/- 12.04 in controls. The residual DNA damage (RD) was significantly greater (P<0.01) in asbestos-exposed workers (35.62%) than in controls (27.75%). XRCC1 genetic polymorphism in 104 asbestos-exposed workers was not associated with increased risk of asbestosis. But compared with polymorphisms in the DNA repair gene XRCC1 (polymorphisms in codon 399) and the DNA damage induced by asbestos, the comet scores in asbestosis cases with Gln/Gln, Gln/Arg, and Arg/Arg were 40.26 +/- 18.94, 38.03 +/- 28.22, and 32.01 +/- 11.65, respectively, which were higher than those in non-asbestosis workers with the same genotypes (25.58 +/- 11.08, 37.08 +/- 14.74, and 29.38 +/- 10.15). There were significant differences in the comet scores between asbestosis cases and non-asbestosis workers with Gln/Gln by Student's t-test (P<0.05 or 0.01). The comet scores were higher in asbestosis workers with Gln/Gln than in those with Arg/Arg and in non-asbestosis workers exposed to asbestos, but without statistically significant difference.

CONCLUSIONSExposure to asbestos may be related to DNA damage or the capacity of cells to repair H2O2-induced DNA damage. DNA repair gene XRCC1 codon 399 may be responsible for the inter-individual susceptibility in DNA damage and repair capacities.

Adult ; Aged ; Amino Acid Substitution ; Arginine ; blood ; Asbestos ; toxicity ; Comet Assay ; DNA Damage ; drug effects ; genetics ; DNA Repair ; drug effects ; genetics ; DNA-Binding Proteins ; genetics ; Genotype ; Glutamine ; blood ; Humans ; Hydrogen Peroxide ; toxicity ; Lung Neoplasms ; chemically induced ; genetics ; Lymphocytes ; metabolism ; Middle Aged ; Occupational Exposure ; Polymerase Chain Reaction ; Polymorphism, Genetic ; drug effects ; physiology ; X-ray Repair Cross Complementing Protein 1

The aim of this study was to investigate whether green tea extract (GTE) has the protective effects on excess L-arginine induced toxicity in human mesangial cell. Human mesangial cells treated with L-arginine were cultured on Dulbecco's modified eagle medium in the presence and absence of inducible nitric oxide synthase (iNOS) inhibitor and GTE. The cell proliferation was determined by 3 (4,5-dimethylthiazol- 2-yl)-2, 5-diphengltetrqzolium bromide, a tetrazole assay. The iNOS mRNA and its protein expression were detected by reverse transcription polymerase chain reaction and Western blot, respectively. The concentration of nitric oxide (NO) was measured by NO enzyme-linced immuno sorbent assay kit. L-arginine significantly inhibited the proliferation of human mesangial cells, and induced the secretion of NO to the media. NO production by L-arginine was significantly suppressed by GTE and iNOS inhibitor (p<0.01). The expression level of iNOS mRNA and its protein that was significantly increased by L-arginine was decreased by iNOS inhibitor but not by GTE. GTE protected the mesangial cells from the NO-mediated cytotoxicity by scavenging the NO rather than by iNOS gene expression. Therefore, we conclude that GTE has some protective effect for renal cells against oxidative injury possibly by polyphenols contained in GTE.
Antioxidants/metabolism ; Arginine/metabolism/pharmacology/*toxicity ; Cell Line ; Cell Proliferation ; Cell Survival ; Flavonoids/metabolism ; Glomerular Mesangium/cytology/metabolism ; Humans ; Mesangial Cells/*cytology/metabolism ; Nitric Oxide/chemistry/metabolism ; Nitric Oxide Synthase Type II/metabolism ; Phenols/metabolism ; RNA, Messenger/metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tea