3-nitrotyrosine and Nephritis

The aim of this study was to investigate the therapeutic activity of isoquinoline alkaloid berberine against cisplatin (CP)-induced nephrotoxicity in mice. Berberine was administered at daily doses of 1, 2 and 3 mg/kg by gavage for two successive days, 48 h after intraperitoneal CP injection (13 mg/kg). Mice were sacrificed 24 h after the last dose of berberine. Histopathological changes and the increase in serum creatinine and blood urea nitrogen (BUN) induced by CP were significantly ameliorated by berberine in a dose-dependent manner. Additionally, oxidative/nitrosative stress, evidenced by the increase in renal 4-hydroxynonenal (4-HNE), 3-nitrotyrosine (3-NT), cytochrome P450 E1 (CYP2E1) and heme oxygenase (HO-1) expression, was significantly reduced. The expression of nuclear factor-kappaB (NF-κB), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) was markedly suppressed by berberine, indicating the inhibition of inflammatory response. Treatment of CP-intoxicated animals with berberine also significantly reduced the expression of p53, active caspase-3 as well as autophagy marker light chain 3B (LC3B) in the kidneys. The results of the current study showed the nephroprotective activity of berberine against CP-induced renal injury, which could be attributed to the inhibition of oxidative/nitrosative stress, inflammation, autophagy and apoptosis.

Topics: Aldehydes; Animals; Apoptosis; Autophagy; Berberine; Blood Urea Nitrogen; Cisplatin; Creatinine; Cytochrome P-450 CYP2E1; Kidney; Male; Mice; Mice, Inbred BALB C; Nephritis; Oxidative Stress; Protective Agents; Tyrosine

Coexistence of chronic kidney disease (CKD) and heart failure (HF) in humans is associated with poor outcome. We hypothesized that preexistent CKD worsens cardiac outcome after myocardial infarction, and conversely that ensuing HF worsens progression of CKD. Subtotally nephrectomized (SNX) or sham-operated (CON) rats were subjected to coronary ligation (CL) or sham surgery in week 9 to realize four groups: CON, SNX, CON + CL, and SNX + CL. Blood pressure and renal function were measured in weeks 8, 11, 13, and 15. In week 16, cardiac hemodynamics and end-organ damage were assessed. Blood pressure was significantly lower in SNX + CL vs. SNX. Despite this, glomerulosclerosis was more severe in SNX + CL vs. SNX. Two weeks after CL, SNX + CL had more cardiac dilatation compared with CON + CL (end-diastolic volume index: 0.28 ± 0.04 vs. 0.19 ± 0.03 ml/100 g body wt; mean ± SD, P < 0.001), although infarct size was similar. During follow-up in SNX + CL, ejection fraction declined. Mortality was only observed in SNX + CL (2 out of 9). In SNX + CL, end-diastolic pressure (18 ± 4 mmHg) and tau (29 ± 9 ms), the time constant of active relaxation, were significantly higher compared with SNX (13 ± 3 mmHg, 20 ± 4 ms; P < 0.01) and CON + CL (11 ± 5 mmHg, 17 ± 2 ms; P < 0.01). The diameter of small arterioles in the myocardium was significantly decreased in SNX + CL vs. CON + CL (P < 0.01). Urinary excretion of NO metabolites was significantly lower in SNX + CL compared with both CL and SNX. This study demonstrates the existence of more heart and more kidney damage in a new model of combined CKD and HF than in the individual models. Such enhanced damage appears to be separate from systemic hemodynamic changes. Reduced nitric oxide availability may have played a role in both worsened glomerulosclerosis and cardiac diastolic function and appears to be a connector in the cardiorenal syndrome.

Topics: Animals; Blood Pressure; Cardio-Renal Syndrome; Coronary Stenosis; Disease Models, Animal; Gene Expression; Heart Failure; Ligation; Male; Myocarditis; Nephrectomy; Nephritis; Nitrates; Nitrites; Peptidyl-Dipeptidase A; Prorenin Receptor; Rats; Rats, Inbred Lew; Receptors, Cell Surface; Renal Insufficiency, Chronic; Renin; Thiobarbituric Acid Reactive Substances; Tyrosine; Ultrasonography

Oxidative stress and inflammation are implicated in the pathogenesis of diabetic nephropathy. Because sildenafil citrate (Viagra) has variable cardiovascular benefits, including antioxidative and immunomodulating effects, we investigated its influence on oxidative stress and inflammation in diabetic rat kidney.. Streptozotocin-induced diabetic rats received sildenafil (3 mg/kg/day in drinking water) or not (undosed water) for 8 weeks and were compared to age-matched nondiabetic animals. We evaluated 8-hydroxydeoxyguanosine (8-OHdG; for oxidative DNA damage), inducible nitric oxide synthase (iNOS) and nitrotyrosine (for excessive NO production and peroxynitrite formation), and representative chemoattractants [monocyte chemotactic protein-1, MCP-1; for inflammation and monocyte/macrophage infiltrations (ED-1)] in the kidney.. Sildenafil-treated rats had a lower kidney-to-body weight ratio than untreated diabetic rats. Urinary albumin excretion in diabetic rats decreased significantly after sildenafil treatment without changes in systolic blood pressure. Sildenafil-treated rats had significantly lower urinary and renal cortical 8-OHdG levels than the nonsildenafil group. Sildenafil administration significantly attenuated the increased renal nitrotyrosine protein expression, positive iNOS and ED-1 staining in glomeruli and tubulointerstitium, and nitrotyrosine staining in tubulointerstitium. Cortical MCP-1 RNA expression in the sildenafil group was significantly lower than in the nonsildenafil group.. Sildenafil treatment may attenuate renal damage by ameliorating oxidative and inflammatory injuries in diabetic rats.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Biomarkers; Blotting, Western; Chemokine CCL2; Deoxyguanosine; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Immunohistochemistry; Inflammation Mediators; Kidney; Male; Nephritis; Nitric Oxide Synthase Type II; Oxidative Stress; Piperazines; Purines; Rats; Rats, Sprague-Dawley; RNA, Messenger; Sildenafil Citrate; Streptozocin; Sulfones; Tyrosine; Vasodilator Agents

Renal protection against diabetes-induced pathogenic injuries by multiple exposures to low-dose radiation (LDR) was investigated to develop a novel approach to the prevention of renal disease for diabetic subjects. C57BL/6J mice were given multiple low-dose streptozotocin (STZ; 6 x 60 [corrected] mg/kg) to produce a type 1 diabetes. Two weeks after diabetes onset, some of diabetic mice and age-matched nondiabetic mice were exposed whole body to 25 mGy X-rays every other day for 2, 4, 8, 12, and 16 wk. Diabetes caused a significant renal dysfunction, shown by time-dependent increase in urinary microalbumin (Malb) and decrease in urinary creatinine (Cre), and pathological changes, shown by significant increases in renal structural changes and PAS-positive staining. However, diabetes-induced renal dysfunction and pathological changes were significantly, albeit partially, attenuated by multiple exposures to LDR. Furthermore, LDR protection against diabetes-induced renal dysfunction and pathological changes was associated with a significant suppression of diabetes-increased systemic and renal inflammation, shown by significant increases in serum and renal TNFalpha, ICAM-1, IL-18, MCP-1, and PAI-1 contents. To further explore the mechanism by which LDR prevents diabetes-induced renal pathological changes, renal oxidative damage was examined by Western blotting and immunohistochemical staining for 3-nitrotyrosine and 4-hydroxynonenal. Significant increase in oxidative damage was observed in diabetic mice, but not diabetic mice, with LDR. Renal fibrosis, examined by Western blotting of connective tissue growth factor and Masson's trichrome staining, was also evident in the kidneys of diabetic mice but not diabetic mice with LDR. These results suggest that multiple exposures to LDR significantly suppress diabetes-induced systemic and renal inflammatory response and renal oxidative damage, resulting in a prevention of the renal dysfunction and fibrosis.

Topics: Albuminuria; Aldehydes; Animals; Blotting, Western; Chemokine CCL2; Creatinine; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 1; Diabetic Retinopathy; Intercellular Adhesion Molecule-1; Interleukin-18; Male; Mice; Mice, Inbred C57BL; Nephritis; Random Allocation; Reverse Transcriptase Polymerase Chain Reaction; RNA; Serpin E2; Serpins; Tumor Necrosis Factor-alpha; Tyrosine

The present study was undertaken to identify whether inflammation or oxidative stress is the primary abnormality in the kidney in spontaneously hypertensive rats (SHR). Renal inflammation and oxidative stress were evaluated in 2- and 3-week-old prehypertensive SHR and age-matched genetically normotensive control Wistar-Kyoto (WKY) rats. Blood pressure was similar in WKY and SHR rats at 2 and 3 weeks, of age. Renal inflammation (macrophage and nuclear factor-kappaB) was elevated in SHR at 3 weeks, but not at 2 weeks, of age compared with age-matched WKY rats. Renal oxidative stress (nitrotyrosine, 8-hydroxy-2'-deoxyguanosine and p47phox) was also clearly elevated in 3-week-old SHR compared with age-matched WKY rats. Additionally, NADPH oxidase subunit p47phox was found elevated in 2-week-old SHR compared to age-matched WKY rats. Moreover, antioxidant (N-acetyl-L-cysteine and Tempol) treatment reduced renal inflammation in prehypertensive SHR. We therefore conclude that the oxidative stress appears before inflammation as a primary abnormality in the kidney in prehypertensive SHR.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Acetylcysteine; Age Factors; Animals; Antioxidants; Blood Pressure; Cyclic N-Oxides; Deoxyguanosine; Disease Models, Animal; Disease Progression; DNA Damage; Glutathione; Hypertension; Kidney Cortex; Male; NADPH Oxidases; Nephritis; Oxidative Stress; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Spin Labels; Tyrosine

Here, we investigate the effects of renal ischemia/reperfusion (I/R) on the degree of renal injury, dysfunction, and inflammation in interleukin (IL)-6 knockout (IL-6(-/-)) mice and mice administered a monoclonal antibody against IL-6. IL-6(-/-) mice were subjected to bilateral renal artery occlusion (30 min) and reperfusion (24 h). At the end of experiments, indicators and markers of renal dysfunction, injury, and inflammation were measured. Kidneys were used for histological evaluation of renal injury. Renal expression of the adhesion molecules intercellular adhesion molecule-1 (ICAM-1) and P-selectin, as well as nitration of proteins in the kidney, were determined using immunohistochemistry. In addition, wild-type mice were pretreated (24 and 1 h before ischemia) with an IL-6 antibody to mimic the effects that would be seen in IL-6(-/-) mice. IL-6(-/-) mice and wild-type mice administered the IL-6 antibody demonstrated significantly reduced plasma urea and creatinine levels, indicating reduction of renal dysfunction caused by I/R. Neutrophil infiltration was also significantly reduced in IL-6(-/-) mice and wild-type mice administered the IL-6 antibody subjected to renal I/R. Proinflammatory cytokines (tumor necrosis factor-alpha and IL-1beta) in renal tissues were significantly attenuated in IL-6(-/-) mice to levels seen in wild-type mice. IL-6(-/-) mice demonstrated reduced histological evidence of tubular injury and markedly reduced immunohistochemical evidence of ICAM-1, P-selectin, and nitrotyrosine when subjected to renal I/R. We propose that endogenous IL-6 enhances the degree of renal injury, dysfunction, and inflammation caused by I/R of the kidney by promoting the expression of adhesion molecules and subsequent oxidative and nitrosative stress.

Topics: Animals; Creatinine; Intercellular Adhesion Molecule-1; Interleukin-1; Interleukin-6; Kidney; Lipid Peroxidation; Male; Mice; Mice, Inbred C57BL; Nephritis; P-Selectin; Reperfusion Injury; Tumor Necrosis Factor-alpha; Tyrosine

Endotoxins (lipopolysaccharides; LPS) are known to cause multiple organ failure, including renal dysfunction. LPS triggers the synthesis and release of cytokines and the vasodilator nitric oxide (NO*). A major contributor to the increase in NO* production is LPS-stimulated expression of inducible nitric oxide synthase (iNOS). This occurs in vasculature and most organs including the kidney. During endotoxemia, NO* and superoxide react spontaneously to form the potent and versatile oxidant peroxynitrite (ONOO-) and the formation of 3-nitrotyrosine (nTyr)-protein adducts is a reliable biomarker of ONOO- generation. Therefore, the present study was aimed at investigating the role of endogenous nitric oxide in regulating Na+,K(+)-ATPase activity in the kidney, and at investigating the possible contribution of reactive nitrogen species (RNS) by measuring of iNOS activity. In addition, the present study was aimed at investigating the relationship between nTyr formation with iNOS and Na+,K(+)-ATPase activities. Previously in our study, nTyr was not detectable in kidney of normal control animals but was detected markedly in LPS exposed animals. In this study, kidney Na+,K(+)-ATPase activity were maximally inhibited 6 h after LPS injection (P:0.000) and LPS treatment significantly increased iNOS activity of kidney (P:0.000). The regression analysis revealed a very close correlation between Na+,K(+)-ATPase activity and nTyr levels of LPS treated animals (r = -0.868, P = 0.001). Na+,K(+)-ATPase activity were also negatively correlated with iNOS activity (r = -0.877, P = 0.001) in inflamed kidney. These data suggest that NO* and ONOO- contribute to the development of oxidant injury. Furthermore, the source of NO* may be iNOS. iNOS are expressed by the kidney, and their activity may increase following LPS administration. In addition, NO* and ONOO- formation inhibited Na+,K(+)-ATPase activity. This results also have strongly suggested that bacterial LPS disturbs activity of membrane Na+,K(+)-ATPase that may be an important component leading to the pathological consequences such as renal dysfunction in which the production of RNS are increased as in the case of LPS challenge.

Topics: Animals; Free Radicals; Guinea Pigs; Kidney; Lipopolysaccharides; Nephritis; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peroxynitrous Acid; Reactive Nitrogen Species; Regression Analysis; Sodium-Potassium-Exchanging ATPase; Tyrosine

Inducible nitric oxide synthase (iNOS)-deficient mice were used to examine the role of iNOS in Escherichia coli-induced urinary tract infection (UTI). The toxicity of nitric oxide (NO)/peroxynitrite to bacteria and host was also investigated. The nitrite levels in urine of iNOS+/+ but not iNOS/ mice increased after infection. No differences in bacterial clearance or persistence were noted between the genotypes. In vitro, the uropathogenic E. coli 1177 was sensitive to 3-morpholinosydnonimine, whereas the avirulent E. coli HB101 was sensitive to both NO and 3-morpholinosydnonimine. E. coli HB101 was statistically (P < 0.05) more sensitive to peroxynitrite than E. coli 1177. Nitrotyrosine immunoreactivity was observed in infected bladders of both genotypes and in infected kidneys of iNOS+/+ mice. Myeloperoxidase, neuronal (n)NOS, and endothelial (e)NOS immunoreactivity was observed in inflammatory cells of both genotypes. Our results indicate that iNOS/ and iNOS+/+ mice are equally susceptible to E. coli-induced UTI and that the toxicity of NO to E. coli depends on bacterial virulence. Furthermore, myeloperoxidase and nNOS/eNOS may contribute to nitrotyrosine formation in the absence of iNOS.

Topics: Animals; Antibodies; Colony Count, Microbial; Escherichia coli; Escherichia coli Infections; Female; Genotype; Immunohistochemistry; Mice; Mice, Inbred C57BL; Mice, Transgenic; Nephritis; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Nitrites; Peroxidase; Peroxynitrous Acid; Tyrosine; Urinary Tract Infections

In the present paper we studied the role of nitric oxide radicals (NO) on platelet aggregation, fibrinogen deposition, superoxide formation, peroxynitrite formation, hemodynamics, and leukocyte migration in the Thy-1 model of glomerulonephritis. To first study the baseline kinetics of these parameters, groups of anti-Thy-1-treated rats were sacrificed at 1 h, 4 h, 24 h, 3 days, 7 days, and 14 days and compared to controls. Urinary protein excretion was significantly elevated in Thy-1 nephritis at 3 and 7 days. Glomerular macrophages, PMNs, and superoxide anion-positive cells were significantly increased in Thy-1 nephritis. Nitrotyrosine immunoreactivity was absent during the entire study period. Glomerular platelet aggregation was significantly increased in anti-Thy-1 injected rats at 1 h, 4 h, 24 h, and 3 days. Glomerular fibrinogen deposition was significantly elevated at all time points. To elucidate the role of NO in this process, additional groups of anti-Thy-1-injected rats were treated with the NOS inhibitor l-NAME and studied at 24 h. Urinary protein excretion was significantly higher in l-NAME treated Thy-1 rats compared to nontreated Thy-1 rats. Plasma and urine nitrite/nitrate levels were significantly lower in l-NAME-treated Thy-1 rats compared to nontreated Thy-1 rats. Compared to nontreated Thy-1 rats, there were no differences in intraglomerular leukocyte accumulation after treatment with l-NAME. In contrast, we observed a marked increase in platelet aggregation following l-NAME treatment. From these data we conclude that the inflammatory infiltrate in Thy-1 nephritis develops independent of NO radical production, whereas NO radicals prevent the accumulation of platelet aggregates.

Topics: Animals; Blood Pressure; Enzyme Inhibitors; Immunohistochemistry; Isoantibodies; Kidney Glomerulus; Nephritis; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Platelet Aggregation; Proteinuria; Rats; Tyrosine