Urinary Enzyme Activity Research Articles

Long-Term Consequences of Increased Activity of Urine Enzymes After Cardiac Surgery - A Prospective Observational Study.

IntroductionCardiac surgery associated AKI (CSA-AKI) complicates recovery and may be associated with a greater risk of developing chronic kidney disease and mortality. The aim of this study was to assess long-term clinical consequences of transient increased activity of urinary enzymes after cardiac surgery (CS).MethodsAn observational study was conducted in a group of 88 adult patients undergoing planned coronary artery bypass grafting (CABG), but all samples were obtained from 79 patients. The activity of urinary enzymes: N-acetyl-beta-glucosaminidase (NAG), arylsulfatase A (ASA) and beta-glucuronidase was evaluated in sequential urine samples. A comparative analysis of biochemical parameters was performed regarding the occurrence of acute kidney injury (AKI) defined by KIDGO at 24 hours, at day 30 and 5-years after the operation.ResultsDuring the first 24 hours after CS AKI was diagnosed in 13 patients. A comparison of the activity of urinary enzymes in pre-defined time-points showed significant differences for ASA and NAG (post OP-sample p < 0.028 and p < 0.022; POD 1 sample p < 0.004 and p < 0.001 respectively). No patient had any biochemical or clinical features of kidney failure at day 30. In the AKI group kidney failure was diagnosed in 36% of patients within 5 years of follow-up as opposed to 5% in the no AKI group. The activities of tubular enzymes in urine reflect a general injury of kidney tubules during and after the operation. However, they are not ideal biomarkers for prediction of the degree of kidney injury and further poor prognosis of CS-AKI.

Assessment of urine sample quality by the simultaneous measurement of urinary γ-glutamyltransferase and lactate dehydrogenase enzyme activities: possible application to unravel cheating in drugs of abuse testing.

Evaluation of the simultaneous measurement of urinary γ-glutamyltransferase (γGT) and lactate dehydrogenase (LDH) to discriminate fresh from previously frozen specimens in urine drug monitoring. Two widely available photometric tests (Siemens Healthineers Atellica) were used to determine the range of urinary γGT and LDH excretion and to study the decay in urinary enzyme activity under various storage conditions (room temperature, 4-8°C,-18°C,-80°C). From these data, cut-off values were established and evaluated in split (fresh/frozen) specimens. Both assays allow robust, reliable, and simultaneous determination of urinary γGT and LDH. In healthy subjects, the 95% reference intervals for enzyme activity in native urine were γGT: 24.4-100.4U/g Crea (creatinine) and LDH: 2.5-45.8U/g Crea. Frozen storage for at least 7days at-18°C resulted in a loss of activity to less than 50% in both enzymes. Cut-offs for frozen samples were γGT≤33.2U/g Crea and LDH≤ 8.4U/g Crea. When applied to 100 sample pairs (fresh/frozen), 86.5% (173/200) of the measurements were conclusive and the combination of concordant enzyme measurements (low γGT/low LDH or high γGT/high LDH) was able to predict the mode of storage with a sensitivity of 96.3% and a specificity of 96.7%. The additional measurements of urinary γGT and LDH can be used to detect previously frozen urine specimens. A simple protocol is proposed to provide additional information on sample quality when deceit is suspected. The procedure can be easily integrated into the standard workflow of urinary drug monitoring.

Peculiarities of Restoration of the Functional Condition of the Kidney Parenchyma in Children with Congenital Defects of the Ureterovesical Segment Depending on Methods of Its Operative Correction (According to Cytokine-enzymological Criteria)

Peculiarities of Restoration of the Functional Condition of the Kidney Parenchyma in Children with Congenital Defects of the Ureterovesical Segment Depending on Methods of Its Operative Correction (According to Cytokine-enzymological Criteria)

Elastolytic activity is associated with inflammation in bladder cancer.

Cancer development and progression is often associated with inflammation. Late diagnosis of inflammation that directly leads to the development of neoplasm-cancer is associated with a reduction in the chance of successful treatment or is associated with therapeutic difficulties. A panel of chromogenic substrates was used for the qualitative determination of the specific activity of enzymes in urine of patients with confirmed inflammatory reaction and/or epithelial neoplasms in particular tumours at various stages of development. Urine of people with excluded inflammation was used as a control group. Proteolytic activity was determined in urine samples collected from patients with epithelial neoplasms and/or inflammation. What is more, we determine human neutrophil elastase activity-related inflammation based on the examination of urine samples. We suspect that the proteolytical activity of urine samples is due to neutrophil response to inflammation, which is directly related to cancer. This is the first study to determine elastolytic activity in bladder cancer urine samples. It supports wider use of urine for inflammation screening.

P0599THE LYSOSOMAL URINE ENZYMES ACTIVITY IN CHILDREN AFTER ACUTE KIDNEY INJURI

Abstract Background and Aims The urgency of the problem of acute kidney injury (AKI) in children is due to the high risk of chronic kidney disease (CKD) as an outcome. Lysosomal enzymes in urine are considered to be informative markers of renal parenchyma damage. The aim of study was to determine the activity of lysosomal enzymes β-galactosidase (GAL) and N-acetyl-β-D-glucosamynidase (NAG) in urine as markers of CKD progression in children after AKI. Method 41 children were examined after AKI with achieving self-diuresis and clinical improvement. The functional state of the kidneys was evaluated by the glomerular filtration rate (Schwartz GFR), the level of albuminuria. Urine enzyme activity was determined and cross-linked to mmol urinary creatinine. The control (reference) group consisted of 28 children who were conditionally healthy, without kidney disease. Results The NAG activity was 8 times higher level than in the reference group of healthy children (87/46;193 vs. 15/11;18, p&amp;lt;0.001), and GAL was elevated in 3 times either (34/22;45 vs. 10/6;13, p&amp;lt;0.001) in patients with a disease period of up to 2 years after AKI. In patients with follow-up period 2 or more years enzyme activity levels decreased, but remained 4 times higher (NAG: 49/31;109, p &amp;lt;0.001 compared to control; GAL: 35/25;44, p &amp;lt;0.001 compared to control). The high levels of enzyme activity was documented in 73.2% of patients after one year of follow up, but the GFR decrease was found in 22.0%, and albuminuria - only in 34.1%. Conclusion The urine activity of NAG and GAL in children is an informative marker for diagnosing recovery after AKI or CKD progression with renal function decline. This method is non-invasive, inexpensive, and simple to conduct.

CYTOKINE-ENZYMATIC BIOMARKERS FOR RESTORATION OF THE FUNCTIONAL STATE OF RENAL PARENCHYMA IN CHILDREN AFTER RECONSTRACTIVE CORRECTION OF CONGENITAL DEFECTS OF THE URETERO-VESICAL SEGMENT

The aim of this study was to study the peculiarities of changes in cytokine excretion levels of transforming growth factor b1 (TGF-b1), tumor necrosis factor a (TNF-a), monocytic chemoattractant protein 1 (MCP-1) and urinary activity of conditionally renospecific enzymes g-glutamyltranspeptidase (GGT) and neutral a-gtlucosidase (NG) as biomarkers of restoration of the functional state of the kidney parenchyma in children at different times after reconstructive correction of congenital defects of the uretero-vesical segment (UVS). &#x0D; Materials and Methods. Prior to reconstructive correction of congenital defects of UVS the comprehensive clinical and laboratory study was conducted in 45 children aged 4 to 15 years (22 boys, 23 girls) who were diagnosed with megaureter (MU) according to visualization methods: 18 patients with non-refluxing MU (NRMU) and 27 patients with refluxing MU (RMU). 3-4 patients were examined 3-4 weeks after the operation and 24 patients 4-6 months later. The study did not include children with neurogenic bladder dysfunction and pyelonephritis. All patients underwent transvesical ureterocystoneostomy. The reference group consisted of 25 healthy children with normal urinalysis and without an uronephrological pathology. Determination of TNF-a, TGF-b1 and MCP-1 was carried out in urine by the enzyme immunoassay. The results were expressed in units of mass of the substance in terms of unit volume of urine (pg/ml). The activity of GGT and NG was determined by a colorimetric method in our modification using reagent kits. The activity of enzymes in urine was expressed in relative units – in micromoles of reaction products formed after 1 hour of incubation 1 mmol of urine creatinine (µmol/hour/mmol creatinine). We also took into account the fluctuation limits of all investigated indicators. &#x0D; Results. The comparative analysis of TGF-b1, TNF-a, GGT and NG in children with congenital UVS defects before reconstructive operations and the control group demonstrated the statistically reliable difference (p &lt; 0.001). It was stated that in urine of the control group the levels of pro-inflammatory cytokine MCP-1 are not defined at all. The study of this cytokine as a diagnostic and prognostic index of the functional state of renal parenchyma, according to our results, is not advisable. It was also stated that in patients with RMU (baseline) there is an increase in both TGF-b1 and TNF-a levels and the levels of GGT and NG activity compared with the group of patients with congenital NRMU. 3-4 weeks after reconstructive surgery, the levels of TNF-a and the levels of activity GGT and NG urine did not decrease, levels of TGF-b1, on the contrary, even increased. A personalized analysis of the results 4 to 6 months after the transvesical reconstruction revealed that 33.3% of patients showed normalization of TGF-b1 levels (p &lt; 0.001) and a significant decrease in TNF-a, the levels of GGT and urinary NG activity practically reach the range of control. In other cases, despite the recovery of upper urinary tract dynamics, the levels of TNF-a, TGF-b1 and the activity of GGT and NG continued to remain at a fairly high level. &#x0D; Conclusions. The levels of TNF-a and TGF-b1 as well as the levels of activity of conditionally renospecific enzymes GGT and NG of urine in children with congenital malformations of UVS are diagnostically informative biomarkers about progression of pathological process in the kidney and negative influence of pronounced dysfunction of urinary bladder on the pro-inflammatory and pro-fibrotic processes of renal parenchyma in the postoperative period. Taking into account that in 66.7% of cases in children with congenital UVS defects after ureterocystoneostomy disorders in the function of the tubular apparatus of the renal parenchyma and signs of tubulointerstitial fibrosis persist, it is advisable to distinguish these patients into a separate group to avoid the risk for the development of nephrosclerotic disease and to start modern renoprotective therapy timely.

Activity of lysosomal urine enzymes in children after acute kidney injury

The importance of the problem of acute kidney injury in children is due to the high risk of developing chronic kidney disease as a consequence. Lysosomal enzymes of β-galactosidase (GAL) and N-acetyl-β-D-hexozoaminidase (NAG) in urine are considered to be informative markers of renal parenchyma damage. The objective of this study - to determine the activity of lysosomal enzymes in urine as markers of progression of interstitial nephritis in children after acute kidney injury.&#x0D; Methods. 41 children were examined after acute kidney injury, achievement of self-diuresis and improvement. Group I included 22 patients with a disease period of up to 2 years after acute kidney injury, group II - 19 patients with a disease period of 2 years or more. The control (reference) group consisted of 28 children who were conditionally healthy, without kidney disease, as well as without acute diseases and severe metabolic disorders and anatomical defects.&#x0D; Results. NAG and GAL activity were found to exceed 8 and 3 times parameters in the reference group of healthy children, respectively, in patients who had acute kidney injury during the year (p &lt;0.001). In patients with a history of 2 years or more, enzyme levels decreased, but remained higher than normal up to 4 times (p &lt;0.001). The highest level of NAG activity was observed in patients of group 1 with the combination of hemolytic-uremic syndrome with hemolytic anemia, and the lowest - in children with toxic kidney.&#x0D; Determination of the activity of lysosomal enzymes NAG and GAL is a more informative marker of torpid course of interstitial nephritis with a progressive decrease in renal function than indicators of glomerular filtration rate. In twelve months after acute kidney damage in 75% of children, the level of NAG and GAL activity remained significantly elevated at normal glomerular filtration rate. A correlation between glomerular filtration rate and NAG activity (r = -0.473) and GAL (r = -0.333) and a direct correlation between NAG and GAL activity (r = 0.845) were observed.&#x0D; Conclusions. The levels of lysosomal enzymes of NAG and GAL were found to be 8 and 3 times higher than normal, respectively, in patients who suffered acute kidney injury during the year, and in patients with a history of 2 years or more, enzyme activity levels decreased, but remained higher than normal 4-fold (p &lt;0.001). In a year after acute kidney damage in 75% of children, the level of NAG and GAL activity remained significantly elevated despite of normal glomerular filtration rate. Therefore, the detection of NAG and β-galactosidase in the urine of children after acute kidney injury are informative markers of renal parenchyma damage, which may serve as objective criteria for progressive decline in renal functional status, and the lack of normalization of their levels is not a sign of progression of interstitial nephritis in corresponding group of children.

The role of phospholipase A2 in multiple Sclerosis: A systematic review and meta-analysis

Phospholipases A2 (PLA2) are a diverse group of enzymes that cleave the fatty acids of membrane phospholipids. They play critical roles in pathogenesis of neurodegenerative diseases such as multiple sclerosis by enhancing oxidative stress and initiating inflammation. The levels of PLA2 activity in MS patients compared to controls and role of inhibiting PLA2 activity on severity scores in different experimental models are not comprehensively assessed in the light of varying evidence from published studies. The objective of this systematic review is to determine the association between PLA2 activity and multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). We performed a systematic review of six studies that assessed PLA2 activity in MS patients compared to controls and nine studies that assessed PLA2 activity in EAE. sPLA2 nor Lp-PLA2 activity were not increased in MS compared to controls in five of those six studies. A difference in sPLA2 activity was only found in a study that measured the enzyme activity in urine. However, inhibiting cPLA2 or sPLA2 led to lower clinical severity or no signs of EAE in mice, and a lower incidence of EAE lesions compared to animals without cPLA2 inhibition. These findings indicate that PLA2 appears to play a role in the pathogenesis of EAE.

Determination of the reference interval for the activity of N-Acetyl-β-D-Glucosaminidase (NAG) in urine of healthy dogs

ABSTRACT: The diagnosis of acute kidney injury by evaluating the activity of urinary enzymes is an important tool especially for its precocity in relation to methods of assessment of renal function considered late as the installation of injury precedes the function change. This study was performed to determine the reference interval for urinary NAG activity (N-Acetyl-β-D-glucosaminidase) in urine of healthy dogs of different breeds, ages and sexes. It was utilized an automated method for the determination of NAG activity standardized for dog urine samples. Through statistical analysis it was observed that NAG is positively correlated with the age of the animal and urine specific gravity but is not interfered by sex or weight. Based on the determination of urinary activity and after correcting the values for a 1,025 urine specific gravity was obtained an reference interval of X ‘= 3.62U/L±0.66U/L.

PATHOGENIC ASPECTS OF FUNCTIONAL DISORDERS OF THE URINARY SYSTEM IN TERM NEONATES WITH PATHOLOGY OF EARLY NEONATAL PERIOD

Introduction. Formation of the majority of disease conditions in childhood and adulthood is associated with prolongation of pathological processes occurring in the periods of antenatal development and neonatal period. The main damaging factor in the development of disadaptation syndrome in neonates is hypoxia. Increase of knowledge concerning pathogenic links of post-hypoxic damage of the kidneys in the context of the body integrity is rather topical. Objective: to determine pathogenic links promoting formation of functional disorders of the urinary system condition in term neonates with pathology of early neonatal period. Materials and methods. Clinical-paraclinical examination of 80 term neonates has been carried out. The infants divided into four groups depending on the severity degree of disorders of the somatic and neurologic status and renal dysfunction. We used factor analysis of correlation dependences between the main markers of renal dysfunction was applied using the method of principal components in case of a turn of the primary varimax row by means of Statistica Program. Laboratory methods of examination included detection of the levels of creatinine, urea, potassium, sodium in the blood serum and urine; the level of cystatin C in the blood serum with calculation of glomerular filtration rate by creatinine and cystatin C; neutrophil gelatinase-associated lipocalin, total protein, albumin, immunoglobulin G, α1-microglobulin, β2- microglobulin in urine. Examination of infants included also detection of indices of the pro-oxidant system (intensity of oxidative modification of proteins in the blood, malonic dialdehyde in erythrocytes and urine), and antioxidant defense system (ceruloplasmin, HS-groups in plasma, catalase, glucose-S-transferase and γ-glutamyl trasnferase in plasma, glutathione reductase and glucose-6-phosphate dehydrogenase in erythrocytes. Activity of enzymes in urine was investigated and their ratio to the level of creatinine in urine (cholinesterase, aspartate aminopeptidase, alanine aminopeptidase, alkaline phosphatase, lactate dehydrogenase, γ-glutamyl transpeptidase. Results and discussion. By means of Kettel method with detection of «Screen plot» criterion it determined six major factors which are important in understanding the character of correlation dependences between the indices involving 63.3% of general dispersion. Complex interrelated mechanisms of equilibrium disorders between stress-induced and stress-limited systems were found to be in the basis of formation of renal dysfunction in term neonates with disadaptation syndrome. At the same time, under conditions of moderate oxygen starvation activation of defense mechanisms of the body is detected, their action is directed to stabilization of hemodynamic and neuro-endocrine mechanisms, activation of metabolic processes promoting maintenance of the stability of the major vital functions including those of the urinary system. Severe hypoxia is associated with deep metabolic disorders with exhaustion of energy and plastic cellular pool and development of pathologic oxidative stress resulting in to destruction of anatomical integrity of the glomerular and tubular renal apparatus, damage of the cellular structures of the kidney epithelium. Considering the conception of the body «integrity» considerable disorders of the functional state of the main excretory organ are associated with further development of endogenous intoxication syndrome and accumulation of final metabolic products, which intensifies the consequences of porthypoxia lesion with the formation of syndrome of multiple organ failure. Conclusions. Conditions of oxygen starvation together with initiation of reaction of pathologic delivery oxidative stress result in deep disorders of interrelations between pro-oxidant and anti-oxidant components, imbalance of ionic homeostasis, changes of metabolic equilibrium with disorders of energy and plastic supply of the cellular functions, further initiation of the processes of apoptosis and/or necrosis. These stipulate organic changes of the renal structural elements and loss of their functional activity with disorders of the mechanisms of glomerular filtration, tubular reabsorption and secretion against the ground of pathological changes of the renal hemodynamics and imbalance of hormonal homeostasis. Understanding of the main pathogenic links of renal dysfunction formation in neonates of the first week of their life can enable to improve the ways of therapeutic correction directed to the elimination of pathological signs and prevention of complications in future.

Urinary N-acetyl-β-D-glucosaminidase (NAG) activity in the early detection of diabetic nephropathy

One of the serious outcomes of diabetes mellitus is nephropathy. Measurement of microalbuminuria is a routine clinical practice for screening the diabetic nephropathy, but the injury to the kidney may be happening even without microalbuminuria. The association between urinary enzyme activities of N-acetyl-β-D-glucosaminidase (NAG) and angiotensin converting enzyme (ACE) and urine microalbumin was assessed in this study to define the possible biofactor for detection of early diabetic nephropathy. Urinary enzyme activities of NAG and ACE and urine microalbumin of 24 h, serum ACE, and some other clinical features are investigated in 35 type 2 diabetic patients. Glycated hemoglobin (HbA1c), triglycerides, serum ACE, and urine NAG were significantly elevated in diabetic groups compared to the healthy controls. There was no relation between urine NAG and microalbuminuria except in the group of diabetic patients which had urine NAG activity upper than 25 IU/ml; there was a correlation between urine NAG and serum ACE. We may conclude that before the finding of microalbumin in urine, the elevated urine NAG, as an early indicator of renal damage, is associated with serum ACE which is related to kidney vascular microangiopathies.

Proteomic characterization of serine hydrolase activity and composition in normal urine

BackgroundSerine hydrolases constitute a large enzyme family involved in a diversity of proteolytic and metabolic processes which are essential for many aspects of normal physiology. The roles of serine hydrolases in renal function are largely unknown and monitoring their activity may provide important insights into renal physiology. The goal of this study was to profile urinary serine hydrolases with activity-based protein profiling (ABPP) and to perform an in-depth compositional analysis.MethodsEighteen healthy individuals provided random, mid-stream urine samples. ABPP was performed by reacting urines (n = 18) with a rhodamine-tagged fluorophosphonate probe and visualizing on SDS-PAGE. Active serine hydrolases were isolated with affinity purification and identified on MS-MS. Enzyme activity was confirmed with substrate specific assays. A complementary 2D LC/MS-MS analysis was performed to evaluate the composition of serine hydrolases in urine.ResultsEnzyme activity was closely, but not exclusively, correlated with protein quantity. Affinity purification and MS/MS identified 13 active serine hydrolases. The epithelial sodium channel (ENaC) and calcium channel (TRPV5) regulators, tissue kallikrein and plasmin were identified in active forms, suggesting a potential role in regulating sodium and calcium reabsorption in a healthy human model. Complement C1r subcomponent-like protein, mannan binding lectin serine protease 2 and myeloblastin (proteinase 3) were also identified in active forms. The in-depth compositional analysis identified 62 serine hydrolases in urine independent of activity state.ConclusionsThis study identified luminal regulators of electrolyte homeostasis in an active state in the urine, which suggests tissue kallikrein and plasmin may be functionally relevant in healthy individuals. Additional serine hydrolases were identified in an active form that may contribute to regulating innate immunity of the urinary tract. Finally, the optimized ABPP technique in urine demonstrates its feasibility, reproducibility and potential applicability to profiling urinary enzyme activity in different renal physiological and pathophysiological conditions.

Chronic Cadmium Treatment Induces Tubular Nephropathy and Osteomalacic Osteopenia in Ovariectomized Cynomolgus Monkeys

In an attempt to establish a primate model of chronic cadmium toxicosis, we ovariectomized cynomolgus monkeys and treated them with CdCl2 by repeated intravenous injections for 13 to 15 months. The animals showed normocytic-normochromic anemia. The cadmium treatment resulted in increases of urinary enzyme activity indicative of renal tubular degeneration. Histopathology of the kidney revealed renal proximal tubular atrophy accompanied by interstitial fibrosis. Decreased bone mineral density was evident in the trabecular and cortical zones of the lumbar vertebra and femur, with osteoid accumulation around the trabeculae and Haversian canals. Iron deposition at the mineralization front and osteoclasts hyperplasia were indicative of impairment of bone mineralization and an increase of resorption. Blood inorganic phosphorus and 1α,25(OH)2 vitamin D3 levels decreased and urinary deoxypyridinoline level increased in cadmium-treated animals. The renal and bone lesions closely resemble those of itai-itai disease patients, the most severe case of cadmium toxicosis in terms of clinical chemistry and histopathology. Thus, ovariectomized monkeys chronically exposed to cadmium can serve as a primate itai-itai disease model, which is beneficial for developing novel therapeutic methods, investigating the mechanisms of the renal and bone lesions, and establishing more clearly defined criteria for diagnosing the disease.

Vitamin B6 dose-dependently ameliorates renal hemodynamic toxicity of cisplatin in rat model of nephrotoxicity: the histopathologic and biochemical findings

Despite its significant anticancer activity, the clinical use of cisplatin is often limited by its undesirable side effects in the kidney known as nephrotoxicity. It is a common and often overlooked clinical entity that presents itself in the setting of oxidative stress-associated diseases in older individuals with renal failure. In this study, we investigated the antioxidant-protecting effects of vitamin B6 in the kidney, with a view on the vasoregulatory role of renal pyridoxal 5′-phosphate at reducing the hemodynamic toxicity of cisplatin. Hence, 50 male Sprague–Dawley rats were randomly assigned in one of five groups of the study to receive a corresponding dose of either normal saline, vitamin B6 (200 mg/kg/bw; i.m.) or cisplatin alone (7 mg/kg/bw; i.m.), or in combination with vitamin B6 at low (100 mg/kg/bw; i.m.) and high dose (200 mg/kg/bw; i.m.) for 10 days as animal model of renal failure. Daily administration of cisplatin at a dose of 7 mg/kg/bw resulted in a significant increase in local and systemic oxidative stress of the kidney and a decrease in glomerular function as a result of early hemodynamic toxicity. Histopathological examinations of renal tissues revealed acute tubular necrosis with hyaline cast formation triggered by cisplatin over 9 days of the study, in addition to interstitial nephritis and tubular epithelial loss. Further biochemical studies in HVB group showed the protecting effects of supplemented vitamin B6 at a high dose, including a slowdown in urinary enzyme activity, a significant decrease in plasma lipid peroxidation, and an increased tissue superoxide dismutase activity with recovery in the glomerular hemodynamicity and ATPase activity up to 50 % when compared to the low-dose rats and controls. In high-dose animals, the normal glomerular and tubular function on recovery from toxic renal failure led us to conclude that the antioxidant property of vitamin B6 consistently increases with the dose intensity. The present study also provided evidence that high dose of vitamin B6 prevented both functional and histological renal changes induced by cisplatin in rats, more efficient than low dose of the vitamin.

Vitamin C dose-dependently ameliorates renal hemodynamic toxicity of cisplatin in adult Swiss albino rats: a histopathologic and biochemical study

Nephrotoxicity is usually thought of as a common invariable consequence of hemodynamic toxicity whose effects, including oliguria and dysuria, has largely limited the clinical use of cisplatin. In this study, we investigated the protective effects of low and high dose of vitamin C against cisplatin-induced rat nephrotoxicity. Hence, 50 adult male Swiss albino rats were randomly divided into five equal groups to receive a corresponding dose of either normal saline as control, vitamin C (600 mg/kg/BW, i.v.), or cisplatin alone (7 mg/kg/BW, i.p.) or in combination with vitamin C at low dose (200 mg/kg/BW, i.v.) and high dose (600 mg/kg/BW, i.v.) for 9 days. Daily administration of cisplatin at a dose of 7 mg/kg/BW resulted in a significant increase in oxidative stress in renal tissues and plasma and a concomitant decrease in the creatinine clearance and renal blood flow as a result of early hemodynamic toxicity. Histopathological examination revealed acute tubular necrosis with hyaline cast formation triggered by cisplatin over 9 days of experiment. Further biochemical studies showed protecting effects of supplemented vitamin C at a high dose, illustrated by slowdown in the urinary enzyme activity, a significant decrease in plasma lipid peroxidation, and an increased tissue superoxide dismutase activity with recovery in the glomerular hemodynamicity and the ATPase activity up to 50 % when compared to controls and rats receiving low-dose. In high-dose animals, normal glomerular and tubular function on recovery from toxic renal failure led us to conclude that antioxidant property of vitamin C increases with dose, and, therefore, high dose of vitamin C prevents both functional and histological renal changes induced by cisplatin in rats, more efficient than low dose of the vitamin.

Antioxidant protecting effects of vitamin B6 at reducing hemodynamic toxicity of gentamicin in rat model of nephrotoxicity

Routine therapeutic use of gentamicin in patients with preexisting renal failure may confront us with the toxic effects of aminoglycosides in the kidney known as nephrotoxicity. It is a common and often overlooked clinical entity that presents itself in the setting of oxidative stress-associated diseases in older individuals with renal failure. In this study, we investigated the antioxidant protecting effects of vitamin B6 in the kidney, with a view on vasoregulatory role of renal pyridoxal 5′-phosphate at reducing the hemodynamic toxicity of gentamicin. Hence, 50 male Sprague–Dawley rats were randomly assigned in five groups to receive a corresponding dose of either normal saline, vitamin B6 (100 mg/kg/bw; i.m.) or gentamicin alone (80 mg/kg/bw; i.m.), or in combination with vitamin B6 at low (100 mg/kg/bw; i.m.) and high dose (200 mg/kg/bw; i.m.) for 10 days as animal model of nephrotoxicity. Daily administration of gentamicin at a dose of 80 mg/kg resulted in a significant increase in local and systemic oxidative stress and a decrease in glomerular functions as result of early hemodynamic toxicity. Histopathological examinations of renal tissues revealed acute tubular necrosis with hyaline cast formation triggered by gentamicin over 9 days of the experiment, in addition to interstitial nephritis and tubular epithelial loss. Further biochemical studies in HVB group showed the protecting effects of supplemented vitamin B6 at a high dose, including a slowdown in urinary enzyme activity, a significant decrease in plasma lipid peroxidation, and an increased tissue superoxide dismutase activity with recovery in the glomerular hemodynamicity and ATPase activity up to 50 % when compared to low-dose rats and controls. In high-dose animals, normal glomerular and tubular function on recovery from toxic renal failure led us to conclude that antioxidant properties of vitamin B6 consistently increase with dose intensity. The present study also provided evidence that high dose of vitamin B6 prevented both functional and histological renal changes induced by gentamicin in rats, more efficient than low dose of the vitamin.

Dose-related protecting effects of vitamin C in gentamicin-induced rat nephrotoxicity: a histopathologic and biochemical study

Gentamicin remains the mainstay in treatment of gram-negative infections, despite its potential ototoxicity and nephrotoxicity. In this study, we investigated dose-related protecting effects of vitamin C against gentamicin-induced rat nephrotoxicity. Hence, 50 male albino Wistar rats were randomly divided into five equal groups to receive a corresponding dose of either normal saline as control, vitamin C (200 mg/kg/bw, i.m.) or gentamicin alone (80 mg/kg/bw, i.m.) or in combination with vitamin C at low dose (200 mg/kg/bw, i.m.; LVG) and high dose (600 mg/kg/bw, i.m.) for 9 days. Daily administration of gentamicin at a dose of 80 mg/kg resulted in a significant increase in oxidative stress in renal tissues and plasma and a concomitant decrease in the creatinine clearance and renal blood flow as result of early hemodynamic toxicity. Histopathological examinations revealed acute tubular necrosis with hyaline cast formation triggered by gentamicin over 9 days of experiment, in addition to interstitial nephritis and tubular epithelial loss. Further biochemical studies showed protecting effects of supplemented vitamin C at a high dose, including slowdown in the urinary enzyme activity, a significant decrease in plasma lipid peroxidation, and an increased tissue superoxide dismutase activity with recovery in the glomerular hemodynamicity and the ATPase activity up to 50% when compared to controls and low-dose rats (LVG). In high-dose animals, normal glomerular and tubular function on recovery from toxic renal failure led us to conclude that antioxidant properties of vitamin C consistently increase with dose intensity. The present study also provided evidence that high dose of vitamin C prevented both functional and histological renal changes induced by gentamicin in rats, more efficient than low dose of the vitamin.

Early detection of ketoprofen-induced acute kidney injury in sheep as determined by evaluation of urinary enzyme activities

To evaluate early indicators of renal tissue destruction and changes in urinary enzyme activities in sheep during the first hours after acute kidney injury induced by administration of an overdose of an NSAID. 12 adult female sheep. Acute kidney injury was induced in 6 sheep by administration of ketoprofen (30 mg/kg, IV) and detected by evaluation of urinary protein concentration, iohexol clearance, and results of histologic examination. Six sheep served as control animals. Blood and urine samples were collected for up to 24 hours after administration of ketoprofen. Plasma concentrations of urea, creatinine, albumin, and total protein; plasma activities of alkaline phosphatase, acid phosphatase, γ-glutamyl transpeptidase (GGT), matrix metalloproteinase (MMP)-2, and MMP-9; and urinary creatinine and protein concentrations, specific gravity, and activities of alkaline phosphatase, acid phosphatase, GGT lactate dehydrogenase, N-acetyl-β-D-glucosaminidase (NAG), MMP-2, and MMP-9 were measured. Urinary protein concentration and enzyme activities were normalized on the basis of urinary creatinine concentrations and reported as ratios. Many urinary enzyme-to-creatinine ratios increased before the plasma creatinine concentration exceeded the reference value. Urine NAG, lactate dehydrogenase, and acid phosphatase activities were increased beginning at 2 hours after ketoprofen administration, and alkaline phosphatase, GGT, and MMP-2 activities were increased beginning at 4 hours after ketoprofen administration. Most peak urinary enzyme-to-creatinine ratios were detected earlier than were the highest plasma creatinine and urea concentrations. Urinary enzyme activities were sensitive early indicators of acute kidney injury induced by an overdose of an NSAID in sheep.

Potassium dichromate–induced changes on urinary-specific activities of gamma-glutamyl transpeptidase and alanine aminopeptidase enzymes

It has been reported that potassium dichromate–induced nephrotoxicity is evidenced by diminution in creatinine clearance, increase in urinary protein, and structural damage to the proximal tubules. Damage to tissue often leads to the release of enzymes from the injured cells into the extracellular fluids. The aim of this study was to establish whether potassium dichromate induces changes in the urinary-specific activities of gamma-glutamyl transpeptidase and alanine aminopeptidase enzymes. Our results show that the administration of a single intraperitoneal dose of potassium dichromate decreased the activity of such enzymes in urine.

Experimental Studies of Achyranthes aspera (L) Preventing Nephrotoxicity Induced by Lead in Albino Rats

The present study was designed to evaluate the nephroprotective role of methanolic extract of Achyranthes aspera (A.aspera) an important herb in the Indian system of medicine against lead acetate-induced nephrotoxicity in rats. Toxicity was induced in male albino rats (Wistar strain) by administering lead acetate (0.2%) in drinking water for 6 weeks, followed by extract of A. aspera (200 mg/kg body weight). Changes in kidney weights encountered upon lead administration improved after extract with A. aspera. Lead damage to the urine was evident from increase in the activity of γ-glutamyltranspeptidase (γ-GT), Cathespin D, alkaline phosphatase (ALP), acid phosphatase (ACP), β-glucuronidase lactate dehydrogenase (LDH) and N-acetyl-β-D-glucosaminidase (NAG) in urine along with some urinary constituents (urea, uric acid, creatinine, protein and phosphorous). The effects of lead were also studied in kidney (γ-GT, β-glucuronidase, NAG, Cathespin D and LDH) and showed a decline upon extract administration. Increased activities of urinary enzymes were accompanied by increase in the urinary constituents. Treatment with methanolic extract of A. aspera after lead induction completely ameliorated the lead-induced renal damage.