Contrast Media Group Research Articles

Astaxanthin attenuates contrast agent-induced acute kidney injury in vitro and in vivo via the regulation of SIRT1/FOXO3a expression.

The study was processed to investigate the effect of astaxanthin (AST; 3,3-dihydroxybeta, beta-carotene-4,4-dione) on the acute kidney injury induced by iohexol and the relationship with SIRT1/FOXO3a signal pathway. Thirty male Sprague Dawley rats were randomly divided into five groups as follows: control group (CON; olive oil only), contrast media group, astaxanthin control group (100mg/kg), low astaxanthin dose group (LAG, 50mg/kg) and high astaxanthin dose group (HAG, 100mg/kg). As followed, serum creatinine (SCr), blood urea nitrogen (BUN), the oxidative stress markers and apoptosis-related proteins were detected. Human proximal tubular epithelial cells (HK-2) were cultured in DMEM/F12 medium in vitro and then randomly divided into appropriate experimental groups: normal group (N), dimethyl sulfoxide (DMSO), iohexol group (I), iohexol+(1.0, 10.0μmol/L) astaxanthin group (I+LAST; I+HAST), iohexol+SIRT1 inhibitors (nicotinamide) group (NA) and iohexol+si-RNA FOXO3a group (si-RNA FOXO3a); when cultured for 24h, cell proliferation ability was tested by cell counting kit (CCK-8), reactive oxygen species (ROS) were detected by flow cytometry and the expression of SIRT1 and FOXO3a were observed using western blot. At the end of the experiment, the levels of SCr, BUN and malondialdehyde (MDA) were all increased in the CM group. The LAG and HAG reduce superoxide anion (SOD) activity, catalase (CAT) activity, glutathione peroxidase (GPx) activity and glutathione (GSH) content, as well as SCr and BUN level. Moreover, apoptosis-associated proteins, caspase 3 p17, bax and bcl-2 were upregulated. In HK-2 cells, after adding iohexol, proliferation and intracellular ROS levels were significantly increased. Using astaxanthin in advance after the intervention, the result is opposite. SIRTl inhibitors NA can reduce the expression of SIRTl and decrease the expression of FOXO3a protein. Si-RNA FOXO3a reduces the expression of FOXO3a but had no significant effect on the expression of SIRT1. Our study demonstrates that the intervention of astaxanthin could attenuate the oxidative stress and apoptosis in contrast-induced acute kidney injury (CI-AKI), and the SIRT1/FOXO3a pathway participates in the contrast-induced apoptosis of HK-2 cells. Finally, astaxanthin reduces CI-AKI by suppression of apoptosis, which may be through inhibition of SIRT1/FOXO3a pathways.

Impact of various doses of curcumin on contrastmedia induced nephrotoxicity: a histopathological andbiochemical study

Introduction: Contrast-induced nephropathy (CIN) is a cause of acute renal failure (RF) that canlead to certain complications such as chronic RF. Acute and chronic RF may need to dialysis andthe need for dialysis, elongates hospital stay, increases costs, and finally increases mortality rate.Currently, the use of different antioxidants to prevent nephrotoxicity is the main focus of manystudies in this field. Curcumin (CUR) is one of these compounds as the main isolated compoundfrom the essential oil of turmeric underground stem. CUR has numerous pharmaceuticalproperties such as antioxidant, anticancer, and antimicrobial. Objectives: The aim of this study was to investigate the effect of various doses of CUR onbiochemical and histopathological parameters in CIN.Materials and Methods: To conduct this study, 36 Wistar rats were divided into six groups of 6each; negative control (NC) did not receive any drugs. Positive control (PC) was intraperitoneallyinjected with 10 ml/kg contrast media. CUR 50 and 250 mg/kg/d (CUR50, CUR250) groups werereceived intraperitoneally CUR suspended in corn oil for 10 days. CUR 50 or CUR 250 plus contrastmedia (CUR50 + CM, CUR250 + CM) groups were received intraperitoneally CUR + CM with 10mL/kg/d of contrast media and CUR suspension for 10 days. Results: The results showed that CUR caused a significant decrease in serum creatinine (Cr),blood urea nitrogen (BUN), and the percentage of debris, vacuolization, dilatation and renal tissuedegeneration of renal tubules (P < 0.05). Conclusion: We found the positive impact of CUR to protect kidney against the adverse effectsof contrast media. Hence this compound might be useful against contrast induced acute kidneyinjury in patients at risk of contrast media induced nephrotoxicity.

Iodixanol versus Iopromide at Coronary CT Angiography: Lumen Opacification and Effect on Heart Rhythm-the Randomized IsoCOR Trial.

Purpose To show that equal coronary lumen opacification can be achieved with iso- and low-osmolar contrast media when it is injected at the same iodine delivery rate with contemporary cardiac computed tomographic (CT) protocols and to investigate the cardiovascular effect of iso-osmolar contrast media and the image quality achieved. Materials and Methods Institutional review board approval and written informed consent were obtained for the Effect of Iso-osmolar Contrast Medium on Coronary Opacification and Heart Rhythm in Coronary CT Angiography, or IsoCOR, trial. Between November 2015 and August 2016, 306 patients (167 [55%] women) at least 18 years old (weight range, 50-125 kg), were prospectively randomized to receive iso-osmolar iodixanol 270 or low-osmolar iopromide 300 contrast media. All coronary segments were assessed for intraluminal opacification and image quality and were compared by using the Student t test. Heart rate, arrhythmia, patient discomfort, and adverse events also were monitored. Results Mean measured coronary attenuation values ± standard deviation were comparable between the iodixanol 270 and iopromide 300 contrast media groups (469 HU ± 167 vs 447 HU ± 166, respectively [P = .241]; 95% confidence interval: -15.1, 60.0), including those from subanalyses. Adjusted for the lower iodine concentration, the mean iodixanol 270 bolus was larger compared with that of iopromide 300 (76.8 mL ± 11.6 vs 69.7 mL ± 10.8, respectively; P < .001). The higher injection rate was associated with higher pressure (777 kPa ± 308 vs 630 kPa ± 252, respectively; P < .001). Although in the iodixanol 270 group patients experienced less heat discomfort (72% vs 86%, respectively; P < .001), no differences in heart rate or rhythm were observed. Conclusion If injected at comparable iodine delivery rates, the iso-osmolar contrast medium iodixanol 270 is not inferior to low-osmolar contrast medium iopromide 300 for assessment of coronary opacification. Iodixanol 270 was associated with less heat discomfort, but did not affect heart rate differently compared with iopromide 300. © RSNA, 2017 Online supplemental material is available for this article.

Reações de hipersensibilidade a meios de contraste em idade pediátrica

Introduction: Even though diagnostic and therapeutic contrast-enhanced procedures are very frequently performed in clinical practice, the underlying contrast media may be associated with a wide range of hypersensitivity reactions.Objective: Overview of epidemiology, clinical presentation, diagnosis and prevention of hypersensitivity reactions to contrast media in pediatric population.Results: There are two major groups of contrast media: radiologic and non-radiologic, and both may cause hypersensitivity reactions. These reactions can be differentiated according to the time interval between contrast administration and the first appearance of symptoms as: immediate (when they occur during the first hour after administration) or non-immediate (when they occur between one hour up to ten days after administration). IgE-mediated and T cell-mediated immunologic mechanisms appear to be involved in these reactions, respectively. Clinical management aims to determine potential culprit and to identify alternative contrast agents via detailed anamnesis, skin tests and even a possible provocation test. In confirmed cases the culprit preparation should be avoided.Conclusions: A systematic approach to cases of hypersensitivity reaction to contrast media contributes to prevent recurrent reactions and to administrate alternative contrast media more safely.

Role of ERK1/2 and JNK phosphorylation in iodine contrast agent-induced apoptosis in diabetic rat kidneys

Background: The risk of contrast-induced acute kidney injury (CIAKI) is significantly increased in patients with diabetes mellitus. This study aimed to investigate molecular mechanisms of contrast media-induced apoptosis in diabetic rat kidneys, especially the involvement of ERK1/2 and JNK signal pathways. Methods: Diabetic Sprague–Dawley rats were induced by intraperitoneal injection of streptozotocin. Ten weeks later the normal and diabetic rats were administered high-osmolar contrast media (HOCM; meglumine diatrizoate) or normal saline (10 mL/kg) injection for 2 consecutive days. At 24 h after the operation, the rats were sacrificed, the blood samples were collected for examining serum creatinine and the kidneys were collected for determining the expression of caspase-3 by immunohistochemistry and the expression of Bcl-2, Bax, upstream signal molecule p-JNK, and p-ERK1/2 by western blotting. Results: The serum creatinine was significantly increased in diabetes + contrast media group (DC group) after operation compared with in the diabetic group (D group; 103.89 ± 9.01 μmol/L vs. 71.52 ± 7.03 μmol/L, p < 0.05). While creatinine clearance rate (Ccr) was significantly decreased in DC group after operation (1.49 ± 0.33 mL/min vs. 2.60 ± 0.54 mL/min, p < 0.05). Especially, in the diabetic kidney, the expression of caspase-3 was also significantly increased after intravenous injection of HOCM compared with normal saline. The expression level of upstream signal molecule p-JNK protein was apparently increased, but p-ERK1/2 protein was significantly decreased (both p < 0.05). Conclusions: The ionic HOCM-induced renal cells apoptosis in diabetic rats through activating the caspase-3 apoptotic pathway, which might be mediated by upstream MAPK (inhibiting p-ERK1/2 expression and promoting p-JNK expression) signal pathways.

Risk and harm of contrast induced nephropathy in critically ill patients

To assess whether intravenous contrast medium would result in acute kidney injury (AKI), and to determine the risk factors associated with contrast induced AKI (CI-AKI) and its outcome. A retrospective observational study was conducted in intensive care unit (ICU) of Fuyang People's Hospital in Zhejiang Province from January 1st 2011 to December 31st 2014. All enrolled critically ill patients had accepted CT scan, and the hospital length of stay was longer than 48 hours, and the patients who needed renal replacement treatment were excluded. Patients were divided into contrast medium group and control group. AKI was defined according to Acute Kidney Injury Network (AKIN) criteria ( serum creatinine content over 26.4 μmol/L or 50% increase of it from baseline within 48 hours). The incidence of AKI was compared between the two groups, and risk factors for CI-AKI were determined by multiple logistic regression analysis. The relationship of CI-AKI and outcomes were also analyzed. A total of 2 370 critically ill patients were enrolled during the period. 474 (20.0%) of the 2 370 patients received contrast medium, and 70 of them suffered from CI-AKI ( 14.8% ). In 1 896 patients who did not receive contrast medium, 235 of them suffered from AKI (12.4%). There was no significant difference in the incidence of AKI between two groups ( χ² = 1.905, P = 0.168). After several confounding factors were adjusted, multiple logistic regression analysis showed that contrast medium was not found to associate with AKI in critically ill patients [ odds ratio (OR) = 1.66, 95% confidence interval ( 95%CI) = 0.72-3.90,P = 0.201 ], and high acute physiology and chronic health evaluation II ( APACHEII) score ( OR = 1.70, 95%CI = 1.33-2.40, P < 0.001), sepsis (OR = 8.06, 95%CI = 3.28-17.80, P < 0.001), shock (OR = 3.57, 95%CI = 1.73-8.01, P < 0.001) and use of nephrotoxic agent (OR = 1.96, 95%CI = 1.25-2.63, P = 0.015) were risk factors of CI-AKI. Ten of 70 patients with CI-AKI died (14.3%), and 21 out of 404 patients without CI-AKI, died (5.2%). There was no significant difference in the mortality rate (χ² = 8.060, P = 0.005 ). It was shown by multiple logistic regression analysis that age (OR=1.30, 95%CI = 1.05-1.71, P = 0.027), male sex (OR = 1.13, 95%CI = 1.05-1.20, P = 0.039), APACHEII score (OR = 1.07, 95%CI = 1.03-1.18, P < 0.001), and sepsis ( OR = 3.29, 95%CI = 1.92-6.46, P < 0.001) were highly associated with mortality of critically ill patients in whom contrast medium was used. However, the occurrence of CI-AKI showed no influence on the mortality rate (OR = 1.70, 95%CI = 0.88-3.56, P = 0.227). The use of contrast medium is not a risk factor of CI-AKI in critically ill patients. CI-AKI will not raise mortality rate in ICU patients.

Ozone preconditioning attenuates contrast-induced nephropathy in rats

BackgroundContrast-induced nephropathy (CIN) is an important complication of vascular interventions. Ozone therapy can induce tolerance to ischemic insults, a phenomenon known as ozone oxidative preconditioning (OOP). The aim of this study was to investigate the effects of OOP on CIN. Materials and methodsThirty-two Wistar rats were randomized into four groups (n = 8). The control group had intravenous saline injection. The contrast media (CM) group had intravenous meglumine/sodium diatrizoate injection to form CIN. The ozone (O3) group received intraperitoneal ozone for 5 d before the induction of CIN. The oxygen (O2) group was given an equal amount of oxygen for 5 d before the induction of CIN. The animals were sacrificed 48 h after the administration of contrast agent or saline. Kidneys were harvested, and blood samples were obtained. Renal function tests, serum and renal tissue malondialdehyde (MDA), and nitric oxide (NO) levels and renal oxidant system parameters were determined. Histologic examination was performed for renal injury. ResultsSerum blood urea nitrogen (BUN), creatinine, and serum and renal MDA were increased after contrast exposure. Renal NO was decreased, and there was prominent tubular necrosis in the CM group. Serum BUN, creatinine, serum and renal MDA, and grade of tubular necrosis were decreased in the O3 group as compared with those in the CM group. The levels of serum and renal NO and renal total antioxidant system in O3 group were higher than the levels in the CM group. ConclusionsOOP attenuates experimental CIN. This effect is suggested to be mediated by reinforcement of renal antioxidant defenses and maintenance of renal NO levels.

Antioxidant effect of Phyllanthus emblica extract prevents contrast-induced acute kidney injury.

BackgroundContrast-induced acute kidney injury (CI-AKI) occurs after the administration of intravenous iodinated contrast agents. Oxidative stress has been proposed as one of the most important mechanisms in the pathogenesis of CI-AKI. The objective of this study was to investigate the antioxidant effect of the extract from Phyllanthus emblica (PE) in preventing CI-AKI.MethodsMale Sprague Dawley rats were subjected into eight groups, were given water (control) or PE extract (125 or 250 or 500 mg/kg/day) for 5 days before the induction of CI-AKI. Renal function and oxidative stress markers; malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase (CAT) activity were determined in plasma and renal tissue. Kidney sections were performed for histopathological examination.ResultsIn the contrast media (CM) group, increases in blood urea nitrogen and serum creatinine were demonstrated which correlated with severity of tubular necrosis, peritubular capillary congestion and interstitial edema. Moreover, an increase in MDA and a decrease in TAC SOD and CAT activity in CM group were significantly changed when compared with the control (P < 0.05). In contrast, CI-AKI-induced rats administrated with PE extract 250 and 500 mg/kg/day significantly preserved renal function and attenuated the severity of pathological damage (P < 0.05) as well as significantly lower MDA and higher TAC, SOD and CAT than the CM group (P < 0.05).ConclusionsThis study demonstrated the protective role of PE extract against CI-AKI.

GSPE is superior to NAC in the prevention of contrast-induced nephropathy: Might this superiority be related to caspase 1 and calpain 1?

AimsOur study was intended to evaluate the role of inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), caspases 1 and 3 and calpain 1 in the pathogenesis of contrast-induced nephropathy (CIN) and to compare the protective effects of N acetyl cysteine (NAC) and grape seed proanthocyanidin extract (GSPE) against the development of CIN. Main methods32 rats were divided into four groups; control, contrast media (CM), CM+NAC and CM+GSPE. CIN was induced by administration of 7ml/kg diatrizoate. The experiment was discontinued on the ninth day. Blood was collected for blood urea nitrogen (BUN) and creatinine measurement. Rat kidney tissues were removed for histopathological evaluation and the investigation of caspases 1 and 3, iNOS, eNOS, TUNEL and calpain 1. Key findingsA significant increase in BUN, creatinine, renal histopathological injury, TUNEL, caspases 1, 3, calpain 1, iNOS and eNOS was observed in the CM group compared to the control group. There was amelioration in all these parameters in the CM+GSPE group, while there was no significant amelioration in BUN, creatinine and renal histopathological injury in the CM+NAC group. In addition, calpain 1 staining and creatinine were significantly lower in the CM+GSPE group compared to the CM+NAC group. SignificanceOur study showed, for the first time in the literature, that GSPE has a greater renoprotective effect compared with NAC and that this effective protection may be related to decrease in calpain 1 levels.

The first histopathological evidence of trimetazidine for the prevention of contrast-induced nephropathy

Aim: We aimed to investigate the prophylactic effects of trimetazidine (TMZ) against contrast-induced nephropathy (CIN) in rat kidneys. Methods and results: 28 Wistar rats were divided into 4 groups of 7 rats each (control (C), contrast media (CM) TMZ, trimetazidin + contrast media groups (TMZ + CM). The administration of TMZ solution was done on d2, d3 and d4. Fifth day, contrast media was administered at a single dose. On d6 scarification was performed. The oxidant/antioxidant parameters were measured and histopathological scores were performed in kidney tissues. Most of the histopathological scores were significantly higher in the CM group as compared to other groups. Moreover, the scores of the TMZ + CM and C groups were not statistically different. CM group, had significantly higher levels of MDA compared to the C and CM + TMZ groups (562.82 ± 38.15 vs. 419.15 ± 49.01 and 507.34 ± 14.16 01 nmol/mg protein respectively) (p < 0.001). CM group had significantly lower levels of SOD as compared to C, CM + TMZ and TMZ groups (p < 0.05). Conclusion: To the best of our knowledge, this study for the first time, histopathologically demonstrated the effectiveness of TMZ for the prevention of CIN.

Iodinated contrast media cause direct tubular cell damage, leading to oxidative stress, low nitric oxide, and impairment of tubuloglomerular feedback

Iodinated contrast media (CM) have adverse effects that may result in contrast-induced acute kidney injury. Oxidative stress is believed to play a role in CM-induced kidney injury. We test the hypothesis that oxidative stress and reduced nitric oxide in tubules are consequences of CM-induced direct cell damage and that increased local oxidative stress may increase tubuloglomerular feedback. Rat thick ascending limbs (TAL) were isolated and perfused. Superoxide and nitric oxide were quantified using fluorescence techniques. Cell death rate was estimated using propidium iodide and trypan blue. The function of macula densa and tubuloglomerular feedback responsiveness were measured in isolated, perfused juxtaglomerular apparatuses (JGA) of rabbits. The expression of genes related to oxidative stress and the activity of superoxide dismutase (SOD) were investigated in the renal medulla of rats that received CM. CM increased superoxide concentration and reduced nitric oxide bioavailability in TAL. Propidium iodide fluorescence and trypan blue uptake increased more in CM-perfused TAL than in controls, indicating increased rate of cell death. There were no marked acute changes in the expression of genes related to oxidative stress in medullary segments of Henle's loop. SOD activity did not differ between CM and control groups. The tubuloglomerular feedback in isolated JGA was increased by CM. Tubular cell damage and accompanying oxidative stress in our model are consequences of CM-induced direct cell damage, which also modifies the tubulovascular interaction at the macula densa, and may therefore contribute to disturbances of renal perfusion and filtration.

The effect of radiographic contrast media on reperfusion injury in the isolated rat heart.

Background and ObjectivesWe investigated the effects of commonly used contrast media (CM) on myocardial ischemia-reperfusion injury in isolated rat hearts.Subjects and MethodsIsolated rat hearts were subjected to 30 minutes of regional ischemia and 2 hours of reperfusion. The following CM (1 mL/1 L Krebs-Henseleit buffer) were randomly perfused for 15 minutes beginning 5 minutes before reperfusion and ending 10 minutes after reperfusion: iohexol (n=8), iopromide (n=8), ioversol (n=8), iomeprol (n=8), iopamidol (n=7), ioxaglate (n=8), and iodixanol (n=7). The effects of a direct bolus injection of undiluted iohexol, iopromide, or ioxaglate (each n=6) via the aortic root immediately prior to reperfusion were also evaluated. The area of necrosis, expressed as the percentage of the area at risk (AN/AR), and cardiodynamic variables were measured.ResultsThe AN/AR of the control and experimental groups in the order described in methods was 33.7±6.4%, 30.3±7.4%, 34.7±12.6%, 29.2±10.2%, 20.9±7.6%, 22.6±8.7%, 18.8±7.9%, and 19.9±11.4%, respectively. Groups that received iomeprol and ioxaglate exhibited significantly decreased AN/AR values compared to those of control hearts (p=0.042 and p=0.013). No significant differences in the AN/AR were observed between control hearts and the groups injected with a single bolus of CM. No significant hemodynamic changes were noted after reperfusion among the groups.ConclusionThe overall effects of the CM on coronary reperfusion were not deleterious, and better effects were noted in two CM groups. However, it is unclear whether this result was attributed to a specific physiochemical property of the CM.

Incidence and risk of developing contrast-induced acute kidney injury following intravascular contrast administration in elderly patients

BackgroundThe purpose of this meta-analysis was to evaluate the epidemiology of contrast-induced acute kidney injury (CI-AKI) in the elderly.MethodsA literature review was undertaken to determine the incidence of CI-AKI in individuals receiving intravascular contrast medium in the hospital setting.ResultsTwenty-two studies with 186,455 patients were identified. The pooled incidence of CI-AKI was 13.6% in 67,831 patients older than 65 years of age (95% confidence interval [CI] 10.1–18.2, I2=0.496). The pooled odds ratio of CI-AKI in the elderly was 2.55 (95% CI 1.85–3.52, I2=0.34). The high incidence of CI-AKI in the elderly was consistent across different administration route subgroups (intracoronary contrast medium group, 15.5% [95% CI 10.3–22.6]; intravenous contrast medium group, 12.4% [95% CI 8.0–18.8]).ConclusionElderly patients are at greater risk for developing CI-AKI.

128-Slice Acceletated-Pitch Dual Energy CT Angiography of the Head and Neck: Comparison of Different Low Contrast Medium Volumes

BackgroundOur study aims to evaluate the image quality and feasibility of 128-slice dual-energy CTA (DE-CTA) for supra-aortic arteries using reduced amounts of contrast medium (CM). MethodsA prospective study was performed in 54 patients receiving CTA of the head and neck with a 128-slice dual-source CT system. Patients were randomized into two groups with a volume of either 40 mL of CM (Group I) or 50 mL of CM (Group II). Arterial and venous enhancements were recorded for quantitative assessment. Qualitative assessments for images without bone removal (BR) were based on a) the visualization of the circle of Willis and b) streak artifacts due to residual CM in the subclavian or internal jugular veins ipsilateral to injection of CM. Qualitative assessment of dual-energy images using BR was based on the presence of bone remnants and vessel integrity. Quantitative data was compared using the Student t test. The χ2 test was used for the qualitative measurements of streak artifacts in veins while the Mann-Whitney U test was used for the qualitative measurements of images with BR. ResultsArterial and venous attenuation was significantly higher in Group II (P=0.000). Image quality regarding the circle of Willis was excellent in both groups (3.90±0.30 for Group I and 4.00±0 for Group II) . Imaging of the internal jugular veins was scored higher in Group I (1.87±0.72) compared with Group II (1.48±0.51) (P=0.021). Within Group I using BR, mean scores for bone remnants did not differ significantly (P>0.05) but mean scores of vessel integrity (P<0.05) did.ConclusionsContrast-enhanced head and neck CTA is feasible using a scan protocol with low amounts of contrast medium (40 mL) on a 128-slice dual-energy CTA. The 40-mL protocol provides satisfactory image quality before and after dual-energy bone-removal post-processing.

A biochemical study on ameliorative effect of green tea (Camellia sinensis) extract against contrast media induced acute kidney injury.

Introduction: Reactive oxygen species have been shown to be mediators of kidney injury and green tea polyphenols are potent-free radical scavengers.Objectives: In this study we sought to examine whether green tea was able to protect renal toxicity induced by contrast media or not. Materials and Methods: In this experimental study 40 rats were randomly divided into four groups including: 1) control group 2) contrast media group 3) contrast media plus green tea 4) Green tea pretreatment and contrast media group. Blood urea Nitrogen (BUN) and serum creatinine were assessed for severity of kidney injury. Results: Serum creatinine level was higher in group II than in other groups (p<0.001). Treatment (group 3) or pretreatment (group 4) with green tea significantly reduced blood creatinine level when compared with contrast media group (group 2). Conclusion: In this study, beneficial property of green tea, against renal toxicity of contrast media was observed. Green tea extract is an inexpensive, nontoxic, and effective treatment modality in individuals with a risk for acute kidney injury of contrast media.

The Effect of L-Carnitine on Oxidative Stress Responses of Experimental Contrast-Induced Nephropathy in Rats

ABSTRACTThis study was conducted to investigate the prophylactic effects of carnitine against contrast-induced nephropathy (CIN) and its relation to oxidant/antioxidant status in kidney, liver, heart, spleen and lung tissues in a CIN rat model. Twenty-eight adult male Wistar rats were divided into 4 groups, the control, contrast media (CM), carnitine and contrast media+carnitine (CM+carnitine) groups. Animals were placed in individual metabolism cages, and on the 2nd day, rats were deprived of water for 24 hr. On the 3rd day, contrast media were administered to groups CM and CM+carnitine. L-carnitine was administered on days 2, 3 and 4. Histopathological changes were evaluated in the right kidney after euthanization. Superoxide dismutase (SOD) and catalase (CAT) activities and glutathione (GSH) and malondialdehyde (MDA) levels were measured in renal, liver, heart, spleen and lung tissues. The SOD activities in the renal (P<0.05), liver (P<0.001) and spleen (P<0.05) tissues were increased in the carnitine group. The CAT activities in the spleen tissue were decreased (P<0.01) only in the CM group. Renal (P<0.05), liver (P<0.001), spleen (P<0.001) and lung tissue (P<0.01) GSH levels were found to be higher in the carnitine group. In renal, liver and lung tissues, the MDA levels increased in the CM group (P<0.001). The histopathological findings showed that L-carnitine may have a preventative effect in alleviating the negative effects of CIN. Similar to this, L-carnitine may play a major role in the stability of the antioxidant status in the kidney, liver, spleen and lung of the CIN rat model.

The effect of carvedilol and nebivolol on contrast nephropathy

Aim: This study examined biochemical, histopathological and antioxidant effects of the carvedilol and nebivolol on contrast induced nephropathy (CIN). Methods: Forty male Wistar-albino rats were divided into six groups. Control group (C, n=6), contrast medium group (CM, n=6), carvedilol group (CV, n=7), carvedilol+contrast group (CVCM, n=7), nebivolol group (N, n=7), nebivolol+contrast group (NCM, n=7). At the beginning of the study, blood samples were taken from tail veins of rats. All rats were taken to a 72 hour dehydration period. For three days, 2mg/kg carvedilol which was diluted in 1% DMSO was administered to the rats in group 3 and 4 and 1mg/kg nebivolol was administered to the rats in group 5 and 6 with orogastric lavage. Also 2 ml/kg 1% DMSO consisting 0.9% NaCl solution was administered with orogastric lavage to C and CM groups. In the third day of dehydration, 6 ml/kg diatrizoate was intravenously administered via tail vein to the groups CM, N and NCM. 6 ml/kg 0.9%NaCl solution was intravenously administered via tail vein to C, CV and N groups. Rats were sacrificed, and right kidney was kept to measure total antioxidant status (TAS), superoxide dismutase (SOD) and malondialdehyde (MDA) levels. Results: Histopathologically changes were significantly higher in CM group (Table 1). Although it was not statistically significant, in the CM group creatinine levels were increased. Despite exposure to contrast medium, CVCM and NCM groups did not differ in terms of histopathological findings from control group. In CV group, interstitial inflammation and other histopathological findings were remarkably lower compared to the C group. MDA levels were decreased and TAS levels were significantly increased in CVCM and NCM compared to the CM group. Although not statistically significant, levels of SOD increased in both group compared to CM group. View this table: Table 1 Conclusion: This study demonstrated the protective role of carvedilol and nebivolol against CIN. Antioxidant properties of these drugs may have an effect in this.

Effect of trimetazidine on contrast induced nephropthy in rats

Purpose: We aimed to investigate the prophylactic effects of trimetazidine against contrast induced nephropathy (CIN) in rat kidney tissues. Methods: 28 wistar rats were divided into 4 groups of 7 rats each (control (C), contrast media (CM), trimetazidine (TMZ), trimetazidin + contrast media groups (TMZ+CM).Second day,contrast media (Omnipaque 300 mg I/ml) was administered at a single dose of 10 ml/kg into the tail vein. The administration of TMZ solution (10 mg/kg/day) was done on the second, third, and fourth days. After sacrification, the left kidney was dissected for measuring the SOD, CAT, GSH and MDA levels. The histopathological evaluation of the right kidney was performed by a pathologist using a semiquantitative scale of 0 to 3. Results: All histopathological scores were significantly higher in the CM group as compared to other groups.Moreover the scores of the CM+TMZ and C groups were not statistically different (Table 1).CM group, had significantly higher levels of MDA compared to the C group (562,82±38,15 versus 419,15±49,01 nmol/mg protein) (p 0.05).CM group had significantly lower levels of SOD as compared to C,CM+TMZ and TMZ groups (2,54±0,26 versus 3,73±0,42, 3,72±0,37 and 3,87±0,20 U/mg protein respectively) (p<0.05). View this table: Table 1 Conclusion: To the best of our knowledge, this study, for the first time,histopathologically demonstrated the effectiveness of TMZ for the prevention of CIN.Antioxidant properties of TMZ might have contributed to these findings.

Incidence and severity of acute adverse reactions to intravenous iodinated contrast media: 8-year experience in King Chulalongkorn Memorial Hospital

Background: Increasing numbers of acute adverse reactions to contrast media are being seen. Institutional information about incidence and severity of acute adverse reactions to contrast media is essential to inform radiologists of the both common and life-threatening acute adverse reactions encountered. Objectives: We determined the overall, type-specific and severity of acute adverse reactions to intravenous iodinated contrast media at King Chulalongkorn Memorial hospital between January 2002 and December 2009. Methods: This retrospective study reviewed 663 report forms for acute adverse reactions to contrast media among 74,010 intravenous iodinated contrast injections using five types of contrast media including meglumine/sodium ioxitalamate, iohexol, iopamidol, iopromide, and iobitridol. Results: The overall incidence of acute adverse reactions to iodinated contrast media was about 0.9%. Of these 0.8% were minor, and 0.1% were major reactions. The majority of minor reactions were urticaria and the majority of major reactions were facial edema. One contrast-related death was reported. Incidence of acute adverse reactions to nonionic contrast media was 0.58%, and was 4.29 % in the ionic group. The type-specific incidence of acute adverse reactions was 4.29% for meglumine/sodium ioxitalamate, 0.82% for iohexol, 0.29% for iopamidol, 0.65% for iopromide, and 0.25% for iobitridol. Conclusion: Acute adverse reactions to intravenous iodinated contrast media account for less than one percent of injections. The incidence is higher in the ionic contrast media group. The majority of reactions are mild. However, severe reactions can still be encountered and death related to contrast media exist. Keywords: Acute adverse reactions, contrast media, intravenous, iodinated, incidence, severity

Protective effect of alpha tocopherol on contrast-induced nephropathy in rats.

Contrast-induced nephropathy (CIN) is a prominent cause of in-hospital acute kidney injury occurring after the administration of intravenous radiocontrast medium. Oxidative stress has been proposed as one of the more important mechanisms in the pathogenesis of CIN. The aim of the present study has been to determine the effect of alpha tocopherol on the reduction of renal damage in a rat model of CIN. Male Sprague Dawley rats were subjected into six groups pretreated with alpha-tocopherol (250 or 500 mg/kg/day) or the vehicle tweeen80 for 5 days before the induction of CIN. Renal function and oxidative stress markers; level of malondialdehyde (MDA), total antioxidant capacity (TAC), superoxide dismutase (SOD) activity were determined. Kidney tissues were sectioned for pathohistological examination. In the contrast media (CM) group, an increase in serum urea and creatinine was found. Tubular necrosis and peritubular capillary congestion were demonstrated in this group. Also, an imbalance of oxidative stress markers; an increase in MDA and a decreased SOD activity in kidney were shown. On the contrary, in CIN-induced rats administrated with alpha-tocopherol group, a significant reduction of renal function and renal MDA, together with a significant increase of renal SOD, were observed. Interestingly, a reduction in MDA and an increase of TAC in serum, along with prevention of tubular injury, were demonstrated in this group, as compared to the CM group. This present study demonstrated that alpha tocopherol showed protective effect on the rat renal damage induced CIN. Therefore, this vitamin could be used as an antioxidant to attenuate the radiocontrast oxidative damage.