Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0920646 (renal ischemia)
 2,515 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Prolonged ischemia amplified iscehemia/reperfusion (IR) induced renal apoptosis and autophagy. We hypothesize that ischemic conditioning (IC) by a briefly intermittent reperfusion during a prolonged ischemic phase may ameliorate IR induced renal dysfunction. We evaluated the antioxidant/oxidant mechanism, autophagy and apoptosis in the uninephrectomized Wistar rats subjected to sham control, 4 stages of 15-min IC (I15 x 4), 2 stages of 30-min IC (I30 x 2), and total 60-min ischema (I60) in the kidney followed by 4 or 24 hours of reperfusion. By use of ATP assay, monitoring O2-. amounts, autophagy and apoptosis analysis of rat kidneys, I60 followed by 4 hours of reperfusion decreased renal ATP and enhanced reactive oxygen species (ROS) level and proapoptotic and autophagic mechanisms, including enhanced Bax/Bcl-2 ratio, cytochrome C release, active caspase 3, poly-(ADP-ribose)-polymerase (PARP) degradation fragments, microtubule-associated protein light chain 3 (LC3) and Beclin-1 expression and subsequently tubular apoptosis and autophagy associated with elevated blood urea nitrogen and creatinine level. I30 x 2, not I15 x 4 decreased ROS production and cytochrome C release, increased Manganese superoxide dismutase (MnSOD), Copper-Zn superoxide dismutase (CuZnSOD) and catalase expression and provided a more efficient protection than I60 against IR induced tubular apoptosis and autophagy and blood urea nitrogen and creatinine level. We conclude that 60-min renal ischemia enhanced renal tubular oxidative stress, proapoptosis and autophagy in the rat kidneys. Two stages of 30-min ischemia with 3-min reperfusion significantly preserved renal ATP content, increased antioxidant defense mechanisms and decreased ischemia/reperfusion enhanced renal tubular oxidative stress, cytosolic cytochrome C release, proapoptosis and autophagy in rat kidneys.
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PMID:Ischemic conditioning by short periods of reperfusion attenuates renal ischemia/reperfusion induced apoptosis and autophagy in the rat. 1927 87

The ischemia/reperfusion (I/R) represents a common pathological mechanism that causes renal injuries. A monosaccharide D-allose has been shown to inhibit neutrophil activation, which is involved in the I/R-induced organ injuries. We therefore examined the role of D-ribose in the I/R-induced renal injury using a rat model. D-ribose, a monosaccharide found in all living cells, serves as a key component of adenosine-5'-triphosphate and nicotinamide adenine dinucleotide. Male Wistar rats were divided into the sham, control and D-ribose groups. In the control and D-ribose groups, rats were subjected to 45 min of left renal ischemia, followed by 24 h of reperfusion, while the I/R procedure was not performed in the sham group. Rats were intravenously administered D-ribose (sham group and D-ribose group, 400 mg/kg) or saline (control group) 30 min before ischemia. Blood urea nitrogen (BUN), serum creatinine and urinary N-acetyl beta-D-glucosaminidase (NAG) were measured as indicators of glomerular function and proximal tubular function. We also measured cytokine-induced neutrophil chemoattractant-1 (CINC-1) and myeloperoxidase concentrations to assess neutrophil activation and infiltration, respectively. The tissue sections were scored to evaluate the tubular injury. In the control group, BUN, creatinine, NAG, CINC-1, myeloperoxidase, histological severity score, and number of infiltrating neutrophils were increased following I/R insult, as compared with the sham group. Such increases in biochemical markers, severity score, and infiltrating neutrophils were significantly inhibited in the D-ribose group. Thus, D-ribose ameliorates the I/R-induced renal injury probably by inhibiting neutrophil activation, and may be useful in attenuating the renal injury associated with renal ischemia.
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PMID:D-ribose attenuates ischemia/reperfusion-induced renal injury by reducing neutrophil activation in rats. 1939 71

Sildenafil was the first selective inhibitor of phosphodiesterase-5 (PDE5) to be widely used for treating erectile dysfunction. Many recent studies have investigated the cardioprotective role of sildenafil in animal models. We evaluated the protective effects of sildenafil in experimental renal ischemia-reperfusion (IR) injury in two studies. In study 1, male Sprague-Dawley rats were divided into four groups: sham, sildenafil-treated sham, vehicle-treated IR, and sildenafil-treated IR groups. In study 2, we divided the rats into two groups: sildenafil-treated IR rats and PD98059 (ERK inhibitor)+sildenafil-treated IR rats. Functional parameters of the kidney were evaluated at the molecular and structural levels. Blood urea nitrogen (BUN) and serum creatinine levels were lower in sildenafil-treated IR rats than in vehicle-treated IR rats. The expression of inducible (iNOS) and endothelial nitric oxide synthase (eNOS) proteins in sildenafil-treated IR rats was significantly higher than in vehicle-treated IR rats. Pretreatment with sildenafil in IR rats increased ERK phosphorylation and reduced the renal Bax/Bcl-2 ratio, renal caspase-3 activity, and terminal dUTP nick end-labeling-positive apoptotic cells. In contrast, PD98059 treatment increased BUN and serum creatinine levels and attenuated the sildenafil-induced expression of pERK, iNOS, eNOS, and Bcl-2. PD98059 also increased caspase-3 activity but did not decrease the sildenafil-induced accumulation of cGMP. In conclusion, this study suggests that sildenafil has antiapoptotic effects in experimental IR renal injury via ERK phosphorylation, induction of iNOS and eNOS production, and a decrease in the Bax/Bcl-2 ratio.
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PMID:Pretreatment of sildenafil attenuates ischemia-reperfusion renal injury in rats. 1947 86

The possible protective effect of betulinic acid on renal ischemia/reperfusion (I/R) injury was studied. Wistar Albino rats were unilaterally nephrectomized and subjected to 45 min of renal pedicle occlusion followed by 6 h of reperfusion. Betulinic acid (250 mg/kg, i.p.) or saline was administered at 30 min prior to ischemia and immediately before the reperfusion. Creatinine, blood urea nitrogen (BUN), lactate dehydrogenase (LDH) and TNF-alpha as well as the oxidative burst of neutrophil and leukocyte apoptosis were assayed in blood samples. Malondialdehyde (MDA), glutathione (GSH) levels, Na(+), K(+)-ATPase and myeloperoxidase (MPO) activities were determined in kidney tissue which was also analysed microscopically. I/R caused significant increases in blood creatinine, BUN, LDH and TNF-alpha. In the kidney samples of the I/R group, MDA levels and MPO activity were increased significantly, however, GSH levels and Na(+), K(+)-ATPase activity were decreased. Betulinic acid ameliorated the oxidative burst response to both formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA) stimuli, normalized the apoptotic response and most of the biochemical indices as well as histopathological alterations induced by I/R. In conclusion, these data suggest that betulinic acid attenuates I/R-induced oxidant responses, improved microscopic damage and renal function by regulating the apoptotic function of leukocytes and inhibiting neutrophil infiltration.
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PMID:Betulinic acid protects against ischemia/reperfusion-induced renal damage and inhibits leukocyte apoptosis. 1961 40

Recent studies have shown the remarkable gender differences in the susceptibility or expression of many diseases. The mechanism underlying the gender differences is unclear. In the present study, we evaluated the effects of gender differences and different ischemia time on the renal ischemia-reperfusion injury (IRI). The IRI was induced in the bilateral kidneys of 156 male and 30 female BALB/c mice. Renal function, serum creatinine and blood urea nitrogen, and pathology of the kidneys were examined at 24 hr after IRI. Renal IRI was generated successfully in 182 of 186 mice with a 97.85% success rate. The levels of serum creatinine and blood urea nitrogen were significantly increased in male mice subjected to 30 min, 35 min, or 45 min of renal ischemia and in female mice subjected to 75 min of renal ischemia, compared to the control group at 24 hr after operation. In males following 35 min or 45 min of ischemia and in females following 75 min of ischemia, typical acute tubular necrosis was found in the areas of corticomedullary junction and the histopathologic scores, which represent the degree of renal tissue injuries, were significantly increased. In view of our data, the kidneys of male are much more susceptible to IRI than those of female. The optimal ischemia time of kidney is 35-45 min in males and 75 min in females for generating a stable model of IRI in mice. Investigation of the gender differences might provide a new area for mechanistic study of renal IRI.
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PMID:Gender differences in the susceptibility to renal ischemia-reperfusion injury in BALB/c mice. 1963 37

This study examined the question of whether deficiency of xCT, a cystine-transporter gene, exacerbates ischemia-reperfusion-induced acute renal failure (ARF). Two weeks after the right nephrectomy of male mice at 16-18weeks of age, the left renal vessels were clamped for 45min to induce renal ischemia. After (24h) induction of ischemia, xCT(-/-) mice had elevated concentrations of blood urea nitrogen and creatinine indicative of ARF, while in xCT(+/-) and xCT(+/+) mice, these parameters did not differ from the sham-operated mice. Immunohistochemical analyses of kidneys using antibodies against the oxidative stress markers revealed stronger staining in xCT(-/-) mice compared with xCT(+/+) mice. Induction of xCT mRNA in the kidneys of xCT(+/+) mice was demonstrated using reverse transcriptase (RT)-PCR analysis and was further confirmed using quantitative RT-PCR. These data provide the first in vivo evidence that xCT is induced by oxidative stress and helps prevent ischemia-reperfusion injury to kidneys.
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PMID:Aggravation of ischemia-reperfusion-triggered acute renal failure in xCT-deficient mice. 1969 16

Constriction of the aorta just above the origin of both main renal arteries invariably resulted in elevation of the carotid systolic and carotid mean pressure. The hypertension was not immediate, but developed in about the same time as after constriction of the main renal arteries (3). Constriction of the aorta just below the origin of both main renal arteries had no significant effect on the carotid systolic or carotid mean pressure. Since these results were first reported (1), Rytand (88, 89) has shown by an indirect method, namely, the demonstration of the development of cardiac hypertrophy, that hypertension in the upper part of the body can be produced in the rat by constriction of the aorta just above the origin of both main renal arteries. The immediate effect of constriction of the aorta either below or above the main renal arteries is a fall of blood pressure (femoral mean pressure) below the site of the clamp, the extent of the fall being directly dependent upon the degree of constriction of the aorta. Of particular interest is the eventual elevation of the femoral mean pressure above the normal in some animals with the aorta constricted or even occluded above the origin of the main renal arteries. This was most pronounced and persistent in those animals in which, in addition, the aorta below the origin of the renal arteries, and, in some animals, the main renal arteries, also were constricted. The most important factors which determined this elevation of blood pressure in the lower part of the body were probably increased flow of blood into the vascular bed below the clamp and peripheral vasoconstriction of renal and humoral origin, as in the case of the hypertension produced by constriction of the main renal arteries alone (2-86). Although elevation of the carotid systolic or carotid mean pressure occurred invariably within 24 to 48 hours after the constriction of the aorta above the site of origin of both main renal arteries, yet there was a tendency, after a variable period, for the elevated blood pressure to become lower or even to drop to the original level. Increased constriction, and finally occlusion of the aorta, above the origin of the main renal arteries, and even constriction or occlusion of the aorta below the renal arteries, in addition, failed to induce hypertension that persisted for a long time at a high level. In order to produce this effect, it was necessary to constrict the main renal arteries as well. The possible explanation of the failure of the hypertension to persist for a long time after constriction of the aorta alone, is that the initial ischemia of the kidneys disappeared due to the improvement of the blood flow through the kidneys as a result of (a) the increase of the natural accessory circulation to the kidneys; (b) the increased blood pressure above the site of the clamp and consequent increased flow of blood into the part of the aorta below the clamp; (c) increased pressure below the site of the clamp due, in great part, to peripheral vasoconstriction, and in part to the increased inflow of blood into the lower part of the body through the aorta and collateral channels. For the dog, this method is not necessary for the production of persistent hypertension. Constriction of the main renal arteries is easily performed and is effective for the production of generalized hypertension (2-11). However, constriction of the aorta in addition to constriction of the renal arteries results in greatly elevated persistent hypertension. Constriction of the aorta alone above the origin of the main renal arteries would be useful in the dog only for the production of relatively short periods of hypertension in the upper part of the body. For small animals it may be a more effective and useful method. In the dog, the only technical difficulty encountered was the erosion of the wall of the aorta by the clamp. This may not occur in small animals. In previous studies (2-11) that have dealt with the constriction of the main renal arteries, this accident rarely occurred. When the constriction of the aorta above the origin of the main renal arteries was of moderate degree, or was gradually made very great, the resultant hypertension was not accompanied by impairment of renal excretory function, as determined by urea clearance or by the quantity of urea, creatinine or non-protein nitrogen in the blood, the benign phase of hypertension (3). When the constriction of the aorta was suddenly made very great, impairment of the renal excretory function usually followed, and the animal developed fatal convulsive uremia and characteristic vascular lesions, the malignant phase of hypertension (9). These facts, are all indicative of the renal origin of the hypertension which results from the constriction of the aorta just above the origin of both main renal arteries. Hypertension did not persist for a sufficiently long time to permit any conclusive comparison between the effect of the high and low pressures on the structure of the vascular system, above and below the site of the clamp, respectively. During the period of survival of these animals, no significant differences were observed between the appearance of the vascular system of the upper part of the body and that of the lower part of the body, and significant cardiac hypertrophy did not develop. In the aorta and large arteries, intimal arteriosclerosis was not observed. In the aorta of one old animal several small plaques of calcification were found in the media, but these were present in the portion of the aorta below, as well as above the clamp, and they were no larger or more abundant than were observed in some old dogs with normal blood pressure. Dogs 3-50 and 3-83, that are still alive, with very high blood pressure above the site of the aortic clamps, and relatively low pressure (though greater than normal) below the site of the aortic clamps, will be valuable for the determination of possible differences between the effects of the two levels of blood pressure in the large and small blood vessels. In these dogs also, it will be possible to determine the effect of the persistently high blood pressure on the myocardium. The possible application of the results of this study to the problem of the pathogenesis of human eclampsia is mentioned here for consideration. Since this condition occurs in pregnancy only at a time when the uterus is greatly enlarged, it is at least possible that the mass may press on the aorta or both main renal arteries sufficiently to produce renal ischemia. The suddenness with which the uremic convulsive phase of eclampsia develops is in keeping with this idea. In the dog, an aggravating effect of pregnancy on an already established hypertension has not been noted. As a matter of fact, most of the hypertensive dogs that have become pregnant, have shown a slight or moderate fall, rather than an increased rise of pressure. Since the dog stands with the body in a horizontal position, and does not lie on its back, pressure of the pregnant uterus on the aorta and blood vessels is less than in human beings who stand erect and frequently lie on their backs. The soundness of this suggestion could be tested by placing pregnant women, in the early stage of eclampsia, in a position which could relieve possible pressure on the aorta and main renal arteries. A possible explanation of the fall of pressure in the pregnant hypertensive dogs is the compensatory effect of the normal kidneys of the pups, as in the case of an animal with one main renal artery constricted and the other kidney normal. As has been shown (3, 31, 72), the presence of one normal kidney in an animal hypertensive due to constriction of the other main renal artery, results, after a variable period, in a return of the blood pressure to normal. How the normal kidney acts to produce this effect is not known.
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PMID:STUDIES ON EXPERIMENTAL HYPERTENSION : IX. THE EFFECT ON BLOOD PRESSURE OF CONSTRICTION OF THE ABDOMINAL AORTA ABOVE AND BELOW THE SITE OF ORIGIN OF BOTH MAIN RENAL ARTERIES. 1987 Aug 69

Renal ischemia/reperfusion (I/R) occurs during shock and transplant procedures, greatly affecting outcome. A definitive treatment has not been found. One of the pathophysiological bases of renal I/R injury is the activation of the transcription factor nuclear factor-kappaB (NF-KappaB). We studied the effects of sulfasalazine (SFZ), a NF-kappaB inhibitor, over renal injury in a bilateral renal I/R model in rats. Ten male Wistar rats were subjected to bilateral renal I/R for 45 min followed by 24 h of reperfusion. Half of these received 100 mg/kg SFZ orally before the induction of I/R, while the others received only saline. Five rats served as sham-operated controls. At the end of the reperfusion period, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), blood urea nitrogen (BUN), P-selectin, tumor necrosis factor-alpha (TNF-alpha), intracellular adhesion molecule-1 (ICAM-1), and endothelin-1 (ET-1) concentrations were determined in serum, and renal samples were taken for histological evaluation. After renal I/R, AST, LDH, BUN, TNF-alpha, ICAM-1, and ET-1 serum levels were significantly increased, and tubules were severely damaged on histological analysis, compared to sham controls. SFZ treatment reduced the AST, LDH, BUN, TNF-alpha, and ET-1 elevations, as well as the tubular damage, induced by renal I/R. Serum ICAM-1 and P-selectin were unchanged. These results show that SFZ has a protective effect over renal IR injury. The modulation of adhesion molecules probably does not play a part in these effects, but TNF-alpha and ET-1 modulation could be partly responsible for the effects we observed.
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PMID:Effect of sulfasalazine on renal ischemia/reperfusion injury in rats. 1992 91

Previous studies have reported that selenite, a known antioxidant, protects brain against ischemia/reperfusion injury, which is mediated by oxidative stress. The aim of this study was to investigate whether selenite can protect kidney against ischemic injury by reducing activation of the apoptosis signal regulating kinase 1 (ASK1)/mitogen-activated protein kinase kinase 3 (MKK3)/p38 mitogen-activated protein kinase signaling pathway. The activation and expression of ASK1, MKK3, p38, caspase 3 and cleaved PARP were analyzed by Western blot. Apoptosis of renal tubular epithelial cells was assessed by the terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling method. Malondialdehyde (MDA) levels were measured by the thiobarbituric acid reaction. Blood serum creatinine and blood urea nitrogen level were measured with an Olympus automatic multi-analyzer. We found that selenite attenuated significantly ASK1, MKK3, and p38 phosphorylation at 3 h after renal ischemia. Furthermore, selenite decreased significantly renal epithelial tubular cell apoptosis. In addition, selenite reduced the MDA level. These findings suggest that the protective action of selenite on ischemia renal injury is associated closely with reducing activation of the ASK1-MKK3-p38 signal pathway.
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PMID:Protective effect of selenite on renal ischemia/reperfusion injury through inhibiting ASK1-MKK3-p38 signal pathway. 2000 9

The objective of this research is to investigate the influence of rhBMP-2 on the renal tissue of rat with renal ischemia reperfusion injury. In this program the ischemia reperfusion rat model was established and Wistar rats were divided into six groups: sham operation group (S group), renal ischemia reperfusion injury group (R group), rhBMP-2 treatment group (B1, B2, B3 and B4 group). In the rhBMP treatment groups, rhBMP-2 was intravenously administered with different doses before reperfusion. The contents of TNF-alpha, IL-6, IL-8, MDA and SOD in kidney tissue were observed. At the same time, renal function (blood creatine (Scr) and urea nitrogen (BUN)) were measured. As a result, compared with renal ischemia reperfusion group, administration of rhBMP-2 significantly reduced the content of IL-6 and IL-8 (P < 0.05) and ameliorated renal dysfunction cellular damages (P < 0.05). Higher dose of rhBMP-2 may reduce the content of TNF-alpha (P < 0.05) in kidney tissue. rhBMP-2 also increased activity of SOD and reduced the level of MDA, BUN and Scr. So, we can draw a conclusion that rhBMP-2 treatment attenuates renal ischemia reperfusion injury through inhibition of pro-inflammatory cytokines production and anti-oxidation activity.
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PMID:[Influence of rhBMP-2 on the renal tissue of rat with renal ischemia reperfusion injury and its molecular mechanism]. 2005 29


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