Blood lead level and measured glomerular filtration rate in children with chronic kidney disease

BACKGROUND

The role of environmental exposure to lead as a risk factor for chronic kidney disease (CKD) and its progression remains controversial, and most studies have been limited by a lack of direct glomerular filtration rate (GFR) measurement.

OBJECTIVE

We evaluated the association between lead exposure and GFR in children with CKD.

METHODS

In this cross-sectional study, we examined the association between blood lead levels (BLLs) and GFR measured by the plasma disappearance of iohexol among 391 participants in the Chronic Kidney Disease in Children (CKiD) prospective cohort study.

RESULTS

Median BLL and GFR were 1.2 µg/dL and 44.4 mL/min per 1.73 m2, respectively. The average percent change in GFR for each 1-µg/dL increase in BLL was -2.1 (95% CI: -6.0, 1.8). In analyses stratified by CKD diagnosis, the association between BLL and GFR was stronger among children with glomerular disease underlying CKD; in this group, each 1-µg/dL increase in BLL was associated with a -12.1 (95% CI: -22.2, -1.9) percent change in GFR. In analyses stratified by anemia status, each 1-µg/dL increase in BLL among those with and without anemia was associated with a -0.3 (95% CI: -7.2, 6.6) and -4.6 (95% CI: -8.9, -0.3) percent change in GFR, respectively.

CONCLUSIONS

There was no significant association between BLL and directly measured GFR in this relatively large cohort of children with CKD, although associations were observed in some subgroups. Longitudinal analyses are needed to examine the temporal relationship between lead and GFR decline, and to further examine the impact of underlying cause of CKD and anemia/hemoglobin status among patients with CKD.

Osteopontin does not mitigate cisplatin ototoxicity or nephrotoxicity in adult mice

OBJECTIVE

The goal of this study was to determine whether osteopontin, a molecule with a variety of biologic effects including cell death inhibition, plays an important role in protection of the inner ear and kidney from the toxic effects of the chemotherapeutic drug cisplatin.

STUDY DESIGN

In vivo study using a model system of cisplatin toxicity in adult mice.

SETTING

Virginia Merrill Bloedel Hearing Research Center, University of Washington.

SUBJECTS AND METHODS

Osteopontin+/+ and Osteopontin-/- adult mice were treated with intraperitoneal cisplatin (20 mg/kg) or saline (control). Osteopontin levels were investigated by immunohistochemistry. Auditory brainstem response thresholds and cochlear histology were used to assess ototoxicity, while serum creatinine and renal histology were used to assess nephrotoxicity. For quantitative experiments, 8 to 18 animals were included in each treatment group.

RESULTS

At 72 hours after cisplatin treatment, there was a slight increase in osteopontin levels within the kidney but not in the inner ear. There was no difference in auditory brainstem response threshold shifts, outer hair cell death, or serum creatinine between Osteopontin+/+ and Osteopontin-/- mice. Cochlear and renal histologic damage following cisplatin appeared to be similar in Osteopontin+/+ and Osteopontin-/- mice.

CONCLUSION

Osteopontin is not required for development of normal auditory or renal function. Osteopontin is unlikely to play a role in protection of the inner ear or kidney from acute cisplatin toxicity. Slight increases in renal osteopontin 72 hours after cisplatin injury may be important for regeneration of proximal tubule cells.

Phytochemical analysis

Nephrotoxicity is defined as renal dysfunction that arises as result of exposure to external agents such as drugs and environmental chemicals. The present work was undertaken to carry out the phytochemical study and nephroprotective activity of methanolic extract of Casuarina equisetifolia leaves in gentamicin-induced nephrotoxicity in Wistar rats. Flavonoids and phenolic acids were identified and quantified using high performance liquid chromatography. Subcutaneous injection of rats with gentamicin (80 mg/kg body weight/day) for six consecutive days induced marked acute renal toxicity, manifested by a significant increase in serum urea, creatinine and uric acid levels, along with a significant depletion of serum potassium level, compared to normal controls. Also oxidative stress was noticed in renal tissue as evidenced by a significant decrease in glutathione level, superoxide dismutase, glutathione-S-transferase activities, also a significant increase in malondialdehyde and nitric oxide levels when compared to control group. Administration of plant extract at a dose of 300 mg/kg once daily for 4 weeks restored normal renal functions and attenuated oxidative stress. In conclusion, Casuarina equisetifolia leaves extract ameliorates gentamicin-induced nephrotoxicity and oxidative damage by scavenging oxygen free radicals, decreasing lipid peroxidation and improving intracellular antioxidant defense, thus extract may be used as nephroprotective agent.

Higher incidence of acute kidney injury with intravenous colistimethate sodium compared with polymyxin B in critically ill patients at a tertiary care medical center

Nephrotoxicity was assessed in 173 critically ill patients receiving intravenous colistin or polymyxin B; it occurred in 60.4% and 41.8%, respectively. Further investigation is necessary to elucidate the reason for the difference in nephrotoxicity observed between the groups and to assess the impact of severity of illness and dosing/administration.

Evidence against protective role of sex hormone estrogen in Cisplatin-induced nephrotoxicity in ovarectomized rat model

BACKGROUND

Cisplatin (CP) is an effective drug in cancer therapy to treat the solid tumors, but it is accompanied with nephrotoxicity. The protective effect of estrogen in cardiovascular diseases is well-documented; but its nephron-protective effect against CP-induced nephrotoxicity is not completely understood.

MATERIALS AND METHODS

Thirty ovarectomized Wistar rats were divided in to five groups. Groups 1-3 received different doses of estradiol valerate (0.5, 2.5 and 10 mg/kg/week) in sesame oil for 4 weeks, and at the end of week 3, a single dose of CP (7 mg/kg, intraperitoneal [IP]) was administrated. Group 4 (positive control) received the same regimen as group 1-3 without estradiol without vehicle. The negative control group (Group 5) received sesame oil during the study. The animals were sacrificed 1 week after CP injection for histopathological studies.

RESULTS

The serum level of blood urea nitrogen and creatinine, kidney tissue damage score (KTDS), kidney weight and percentage of body weight change in CP-treated groups significantly increased (P < 0.05), however, there were no significant differences detected between the estrogen-treated groups (Groups 1-3) and the positive control group (Group 4). Although, estradiol administration enhanced the serum level of nitrite, it was not affected by CP. Finally, significant correlation between KTDS and kidney weight was detected (r (2) = 0.63, P < 0.01).

CONCLUSION

Estrogen is not nephron-protective against CP-induced nephrotoxicity. Moreover, it seems that the mechanism may be related to estrogen-induced oxidative stress in the kidney, which may promote the nephrotoxicity.

Risk factors for aminoglycoside-associated nephrotoxicity in surgical intensive care unit patients

BACKGROUND

Aminoglycosides are commonly used antibiotics in the intensive care unit (ICU), but are associated with nephrotoxicity. This study evaluated the development of aminoglycoside-associated nephrotoxicity (AAN) in a single surgical intensive care unit.

MATERIALS AND METHODS

Adult patients in our surgical ICU who received more than two doses of aminoglycosides were retrospectively reviewed for demographics, serum creatinine, receipt of nephrotoxins [angiotensin converting enzyme (ACE) inhibitors, angiotensin-II receptor blockers, diuretics, non-steroidal anti-inflammatory drugs, cyclosporine, tacrolimus, vasopressors, vancomycin and intravenous iodinated contrast] and the need for dialysis. AAN was defined as an increase in serum creatinine >0.5 mg/dL on at least 2 consecutive days. Univariate and multiple regression analyses were performed.

RESULTS

Sixty-one patients (43 males) receiving aminoglycoside were evaluated. Mean age, weight, initial serum creatinine, and duration of aminoglycoside therapy were 58.7 (±15) years, 83.3 (±24.4) kg, 0.9 (±0.5) mg/dL, and 4 (±2.3) days, respectively. Thirty-one (51%) aminoglycoside recipients also received additional nephrotoxins. Seven aminoglycoside recipients (11.5%) developed AAN, four of whom required dialysis and all had received additional nephrotoxins. Only concurrent use of vasopressors (P = 0.041) and vancomycin (P = 0.002) were statistically associated with AAN. Receipt of vasopressors or vancomycin were independent predictors of acute kidney insufficiency (AKI) with odds ratios of 19.9 (95% CI: 1.6-245, P = 0.019) and 49.8 (95% CI: 4.1-602, P = 0.002), respectively. Four patients (6.6%) required dialysis.

CONCLUSIONS

In critically ill surgical patients receiving aminoglycosides, AAN occurred in 11.5% of the patients. Concurrent use of aminoglycosides with other nephrotoxins increased the risk of AAN.

Nephrotoxicity with combination vancomycin-aminoglycoside therapy

OBJECTIVES

The purpose of this paper is to review the medical literature regarding vancomycinaminoglycoside induced nephrotoxicity in the pediatric population. METHODS MEDLINE: (1966 through June 2005), EMBASE (1980 through 1st quarter 2005), and International Pharmaceutical Abstracts databases were reviewed using appropriate search terms for articles related to nephrotoxicity with vancomycin and aminoglycoside use. Case reports, letters to editors, retrospective and prospective studies evaluating nephrotoxicity with the agents in pediatric patients were compiled and summarized. Studies in animals and adults were also briefly reviewed.

RESULTS

One case report, two letters to editors, one retrospective study, and two prospective studies evaluated the nephrotoxicity of combination aminoglycoside and vancomycin therapy in pediatric patients. The collective number of patients in the reports was 165. Patients ranged in age from 3 days to 19 years old. Four out of the six reports, including all of the prospective studies, concluded that combination therapy does not potentiate nephrotoxicity.

CONCLUSIONS

Although vancomycin and the aminoglycosides have been associated with drug induced nephrotoxicity, reports in the literature do not appear to support the idea that the combination of vancomycin and an aminoglycoside is more nephrotoxic than either medication alone.

Effect of angiotensin II type 1 receptor blocker on renal function, arterial blood pressure and parathyroid hormone related protein over expression in cadmium induced nephrotoxicity in adult male rats

OBJECTIVE

To study the possible effect of angiotensin II type 1 Receptor blocker (AT1 blocker) on renal function, arterial blood pressure and parathyroid hormone related protein over expression in cadmium induced nephrotoxicity in adult male rats. Forty five rats were divided randomly into a control (group I), group II, received cadmium chloride at a dose of 5 mg/kg/day, orally, for nine weeks, group III received telmisartan (TEL) treatment (1 mg/kg/day, orally) one week before cadmium administration and continued for ten weeks.

RESULTS

Telmisartan significantly reduced blood urea nitrogen (BUN) and serum creatinine levels which were increased significantly by cadmium. Telmisartan significantly suppressed lipid peroxidation, compensated deficits in the antioxidant defenses (super oxide dismutase (SOD) level and catalase activity), decreased the elevations of nitric oxide (NO) and cadmium ion concentrations in renal tissue observed in Cd-treated rats. Group III had a significant decrease of urinary levels of total protein, N-acetyl-β-d-glucosaminidase (NAG), alkaline phosphatase (ALP) and γ-glutamyl-transpeptidase (GGT) and urinary 8-isoprostanes than those of group II. Telmisartan decreased the systolic blood pressure significantly than those of group II. Histopathological examination revealed that cadmium-induced renal tissue damage was ameliorated by telmisartan treatment. Immunohistochemical analysis revealed that telmisartan significantly decreased the cadmium-induced overexpression of parathyroid hormone receptor 1 (PTHR1) in renal tissue. RT-PCR analysis showed that Cd increased renal expression of PTHrP; however telmisartan could decrease the expression of PTHrP in group III.

CONCLUSION

Blocking AT1 receptors significantly decreases PTHrP over expression and ameliorates renal dysfunction in Cd induced nephrotoxicity. These data suggest that Ang II might contribute to pathophysiology and deleterious effects in cadmium nephrotoxicity.

Comparison of adverse events and hospital length of stay associated with various amphotericin B formulations: sequential conventional amphotericin b/lipid versus lipid-only therapy for the treatment of invasive fungal infections in hospitalized patients

PURPOSE

Patients with invasive fungal infections are often treated initially with conventional amphotericin B deoxycholate (CAB), followed by a switch to lipid-based formulations of amphotericin B (LF-AMB). Our study examined adverse events and hospital length of stay (LOS) among adults who received LF-AMB exclusively or CAB followed by LF-AMB (CAB/LF-AMB).

METHODS

Data were extracted from the Cerner Health Facts database. The study included adults with evidence of infection by Aspergillus, Candida, or Cryptococcus in addition to either renal insufficiency, a clinical condition suggesting intolerance to CAB, or CAB exposure within 90 days of admission. Nephrotoxicity was defined as a serum creatinine (SCr) level exceeding a 100% increase from baseline and an absolute level above 1.2 mg/dL. We used a hierarchical mixed-effect logistic regression model with nephrotoxicity as the outcome for the multivariate analysis.

RESULTS

The study included 327 LF-AMB and 81 CAB/LF-AMB patients with similar demographics and baseline SCr values. The mean pre-to-post percentage increase in SCr levels was greater for CAB/LF-AMB (122.9%) compared with LF-AMB (62.2%) (P < 0.001). The multivariate-adjusted odds ratio of nephrotoxicity was 5.93, for a 95% confidence interval of 2.92 to 12.05 (P < 0.001) for CAB/LF-AMB compared with LF-AMB. Hypokalemia, hypomagnesemia, and infusion-related reactions were more frequent with CAB/LF-AMB. Compared with the LF-AMB group, the CAB/LF-AMB patients had a longer post-amphotericin B LOS (24.1 days vs. 15.7 days, respectively; P < 0.001), with a marginal effect of 4.5 days longer for those receiving CAB/LF-AMB (P = 0.016).

CONCLUSION

In this retrospective study, we noted a significantly longer post-amphotericin B LOS and a greater frequency of adverse events, including nephrotoxicity, for patients whose initial treatment was CAB and who were switched to LF-AMB, compared with patients who received LF-AMB only.

A model for prediction of cisplatin induced nephrotoxicity by kidney weight in experimental rats

BACKGROUND

Cisplatin (cis-diamminedichloroplatinum II; CP) is used widely as an antitumor drug in clinics, but is accompanied with renal toxicity. Cisplatin induced nephrotoxicity consists of change in kidney weight, histological changes in kidney and increase in serum creatinine (Cr) and blood urea nitrogen (BUN). This study was designed to find out a model for prediction of cisplatin induced nephrotoxicity.

MATERIALS AND METHODS

Pathological damage score, kidney weight, BUN, and Cr of 227 rats that were involved in different projects were determined. A total of 187 rats were treated with 7 mg/kg cisplatin and sacrificed 1 week later.

RESULTS

There was a good significant correlation between normalized kidney weight and logarithmic scale of BUN and Cr. Relationship between BUN, Cr or normalized kidney weight and pathology damage score was significant.

CONCLUSION

Normalized kidney weight and pathology damage score is a good predictor of renal function in cisplatin induced nephrotoxicity in experimental rats.

Tenofovir treatment duration predicts proteinuria in a multiethnic United States Cohort of children and adolescents with perinatal HIV-1 infection

BACKGROUND

Tenofovir is associated with renal proximal tubule injury. Such toxicity has not been extensively studied in HIV-1-infected children, in whom tenofovir is increasingly used.

METHODS

History, urine and blood were collected at regular intervals from 448 children and adolescents with perinatal HIV-1 infection followed in the Pediatric HIV/AIDS Cohort study. Relationships between tenofovir use and proteinuria and chronic kidney disease (CKD) outcomes were examined using multivariable logistic regression models. Proteinuria was defined as at least one urine protein/creatinine ratio (uPCR) ≥ 0.2, and CKD as ≥ 2 sequential uPCR ≥ 0.2 or estimated glomerular filtration rates <60 mL/min/1.73 m with no subsequent resolution, or a clinical diagnosis not contradicted by a normal uPCR. Subjects with ≥ 2 uPCR <0.2, and no abnormal uPCR and eGFR comprised the comparison group.

RESULTS

Subjects were 47% male, 72% black, 24% Hispanic, with entry mean age (± standard deviation) of 11.5 ± 2.5 years. Proteinuria prevalence at entry, and annually during 3 years, ranged from 10.3% to 13.7%. The cumulative prevalence of proteinuria was 22% (94/434, 95% confidence interval: 18%-26%) and CKD 4.5% (20/448, 95% confidence interval: 2.7%-6.8%). Duration of tenofovir use was an independent predictor of proteinuria, with >3 years of exposure having the highest risk compared with no exposure (odds ratio: 2.53, 95% confidence interval: 1.23-5.22, overall P = 0.01). Overall, duration of tenofovir use did not significantly predict the presence of CKD.

CONCLUSIONS

Rates of proteinuria and CKD were lower than those seen in the pre-highly active antiretroviral therapy era. However, prolonged exposure to tenofovir increases risk of renal injury.

Modulation of carbon tetrachloride-induced nephrotoxicity in rats by n-hexane extract of Sonchus asper

Sonchus asper is traditionally used in the treatment of renal dysfunction. In the present study, protective effects of S. asper against carbon tetrachloride (CCl4)-induced nephrotoxicity of rats were determined. In this study, 24 male albino rats (190-200 g) were equally divided into four groups. Group I (control group) was given saline (1 ml/kg body weight (b.w.), 0.85% NaCl) and dimethyl sulfoxide (1 ml/kg b.w.); group II was treated with CCl4 (1 ml/kg b.w. intraperitoneally); groups III and IV were administered with CCl4 and after 48 h with S. asper n-hexane extract (SHE; 100 and 200 mg/kg b.w.). All the treatments were given twice a week for 4 weeks. The results revealed that CCl4-induced oxidative stress as evidenced by the significant depletion of antioxidant enzymes, namely, superoxide dismutase, catalase, peroxidase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase, and glutathione contents, while increased lipid peroxidation (thiobarbituric acid-reactive substances contents). Administration of SHE significantly ameliorated (p < 0.01) the activity of antioxidant enzymes and reduced lipid peroxides. Coadministration revealed that S. asper extract can protect the kidney against CCl4-mediated oxidative damage by restoring the activity of antioxidant enzyme, due to the presence of plant bioactive constituents.

Specific nephrotoxicity and cardiotoxicity of BT-CAL®, Sigma Anti-bonding Molecule Calcium Carbonate, in mice

According to a high anti-osteoporotic efficacy of Sigma Anti-bonding Molecule Calcium Carbonate (SAC), repeated-dose toxicities of SAC were investigated to assess its feasibility as drug or functional food ingredient. Male ICR mice were given drinking water containing 0.006, 0.02 or 0.06% SAC for 4 weeks. SAC feeding decreased the body weights and feed and water consumptions of mice in a dose-dependent manner, especially, leading to severe emaciation and 70% death in 3 weeks in the high-dose (0.06%) group. Not only kidney and heart weights, but also the levels of blood urea nitrogen, creatinine, aspartate transaminase, and creatine phospokinase significantly increased after SAC administration, indicative of nephrotoxicity and cardiotoxicity. Such renal and cardiac toxicities were also confirmed by microscopic findings, exhibiting renal crystals and cardiac fibrosis, which may be due to the insoluble crystal formation and calcium overload, respectively. In conclusion, it is suggested that no observed adverse effect level of SAC is lower than 0.006% in mice, and that a long-term intake may cause serious adverse effects on renal and cardiac functions.

Influence of kolaviron and vitamin E on ethylene glycol monoethyl ether-induced haematotoxicity and renal apoptosis in rats

The present study investigated the protective effects of kolaviron, a biflavonoid from the seed of Garcinia kola, and vitamin E on ethylene glycol monoethyl ether (EGEE)-induced haematotoxicity and renal apoptosis in male rats. EGEE was administered at a dose of 200 mg kg(-1) alone or simultaneously administered with kolaviron (100 and 200 mgkg(-1) ) and vitamin E (50 mg kg(-1) ) for 14 days. Results of haematological examination showed that white blood cells, platelets, neutrophils and mean corpuscular haemoglobin concentration were significantly lower, whereas lymphocytes were increased in EGEE-exposed rats compared with those in the control. Administration of EGEE caused a significant decrease in the superoxide dismutase and catalase activities as well as in the glutathione level but significantly increased glutathione Stransferase activity and levels of hydrogen peroxide and lipid peroxidation in kidneys of rats compared with those in the control. Also, EGEE-treated rats showed significant elevation in the serum urea and creatinine with marked increase in the frequency of terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay-positive apoptotic cells in the tubular epithelial cells in comparison with the control. Co-administration with kolaviron or vitamin E exhibited chemoprotective effects against EGEE-mediated haematotoxicity, augmented renal antioxidant status and prevented the induction of renal apoptosis.

Efficacy of Co-administration of Garlic Extract and Metformin for Prevention of Gentamicin-Renal Toxicity in Wistar Rats: A Biochemical Study

BACKGROUND

Gentamicin (GM) nephrotoxicity has been related to oxidative stress. Garlic and metformin (MF) have anti-oxadant activity and therefore, this study was aimed to evaluate the preventive and curative effects of garlic, MF and their combination on GM indeced tubular toxicity in Wistar rats.

METHODS

In a pre-clinical study, 70 male Wistar rats were randomly designated into 7 groups of 10 and treated as follows: Group 1: Received saline for 20 days. Group 2: Were injected 100 mg/kg/d of GM intraperitoneally (ip), for 10 days and saline for 10 more days. Group 3: Received GM for 10 days then 20 mg/kg garlic ip for the next 10 days. Group 4: Received GM for 10 days and MF (100 mg/kg) orally for the next 10 days. Group 5: Received GM for 10 days and a combination of MF and garlic for the next 10 days (100 and 20 mg/kg, respectively). Group 6: The same as group 5but with half-doses of MF and Garlic. Group 7: Received GM for 10 days together with a combination ofMF and garlic. On 20(th) day of the experiment the serum blood urea nitrogen (BUN) and creatinine (Cr) were measured and compared in different groups.

RESULTS

GM injection significantly increased the serum BUN and Cr (P < 0.05). Administration of MF, garlic or their combination with or after injection of GM (high doses) could atenuate BUN and Cr.

CONCLUSIONS

The results indicate that MF and garlic or their combination have curative and protective activity against GM nephrotoxicity.

Preventive and curative effects of ginger extract against histopathologic changes of gentamicin-induced tubular toxicity in rats

BACKGROUND

Gentamicin (GM) is a commonly used aminoglycoside, however, renal toxicity has limited its usage. This study was designed to evaluate the curative and protective effects of Zingiber officinale (ginger) against gentamicin tubular toxicity in rats. The phenolic and flavonoid components and antioxidant activity of ginger were also evaluated.

METHODS

In a preclinical study, 50 male Wistar rats were designated into 5 groups of 10 and treated as follows: Group I: vehicle. Group II: 200 mg/kg/d of ginger for 3 days then, GM (80 mg/kg) for 7 days. Group III: 200 mg/kg ginger orally for 3 days, then ginger plus GM for 7 days. Group IV: GM for 7 days. Group V: GM for 10 days. Group VI: GM for 7 days, then 200 mg/kg ginger orally for 10 days. At the end of the study, the animals were sacrificed and their kidneys were histologically evaluated.

RESULTS

Ginger could prevent degeneration of the renal cells and reduce the severity of tubular damage caused by gentamicin. However, it could not regenerate the GM degeneration.

CONCLUSIONS

The results indicate that ginger is effective as a prophylaxis agent, but has not curative effect.

Mitochondria-mediated mitigatory role of curcumin in cisplatin-induced nephrotoxicity

Cisplatin (CP) is one of the most potent chemotherapeutic anti-tumour drugs, and it has been implicated in renal toxicity. Oxidative stress has been proven to be involved in CP-induced toxicity including nephrotoxicity. However, there is paucity of literature involving role of mitochondria in mediating CP-induced renal toxicity, and its underlying mechanism remains unclear. Therefore, the present study was undertaken to examine the antioxidant potential of curcumin (CMN; a natural polyphenolic compound) against the mitochondrial toxicity of CP in kidneys of male rats. Acute toxicity was induced by a single intra-peritoneal injection of CP (6 mg kg(-1) ). We studied the ameliorative effect of CMN pre-treatment (200 mg kg(-1) ) on the toxicity of CP in rat kidney mitochondria. CP caused a significant elevation in the mitochondrial lipid peroxidation (LPO) levels and protein carbonyl (PC) content. Pre-treatment of rat with CMN significantly replenished the mitochondrial LPO levels and PC content. It also restored the CP-induced modulatory effects on altered enzymatic and non-enzymatic antioxidants in kidney mitochondria. We hypothesize that the reno-protective effects of CMN may be related to its predisposition to scavenge free radicals, and upregulate antioxidant machinery in kidney mitochondria.

Novel derivatives of polymyxins

Polymyxin B and colistin (polymyxin E) are bactericidal pentacationic lipopeptides that act specifically on Gram-negative bacteria, first by disrupting their outermost permeability barrier, the outer membrane (OM), and then damaging the cytoplasmic membrane. Both were discovered in the mid-1950s and subsequently used in intravenous therapy, but soon largely abandoned because of nephrotoxicity. The emergence of extremely multiresistant strains has now forced clinicians to reinstate them in the therapy of severe infections caused by such strains. This article reviews recent attempts to develop novel derivatives of polymyxins that exhibit less toxicity and greater potency than the existing drugs. In addition, studies of novel des-fatty acyl-polymyxin derivatives that display activity against Pseudomonas aeruginosa are included. The review also covers recent studies of derivatives that lack potent bactericidal action, but which disrupt the OM, which increases bacterial permeability to other antibiotics, facilitating their entry into the cell.

Hydration with magnesium and mannitol without furosemide prevents the nephrotoxicity induced by cisplatin and pemetrexed in patients with advanced non-small cell lung cancer

BACKGROUND

The aim of this study was to examine the effect of hydration with magnesium and mannitol without furosemide on the nephrotoxocity accompanying combination chemotherapy using cisplatin and pemetrexed in patients with advanced non-small cell lung cancer (NSCLC).

METHODS

Fifty patients with NSCLC who received cisplatin plus pemetrexed, using either old hydration protocol including normal saline with mannitol and furosemide, or a new one including normal saline with magnesium and mannitol without furosemide were retrospectively analyzed. Nephrotoxicity was compared between patients treated using the old protocol and those treated with the new protocol. Univariate and multivariate analyses were performed to identify the independent factors associated with protection against nephrotoxicity in patients with NSCLC who received cisplatin plus pemetrexed.

RESULTS

Thirty patients received the old hydration protocol, while 20 patients were treated using the new hydration protocol. The patients treated using the new hydration protocol showed a significantly greater increase in creatinine clearance (P=0.0004) and a decrease in the serum creatinine level (P=0.0148) after one course of chemotherapy compared with those treated using the old hydration protocol. There were no differences in the chemotherapeutic response or overall survival between the groups (P=0.572). The new hydration protocol with supplemented magnesium with mannitol without furosemide was an independent factor for the protection against nephrotoxicity induced by cisplatin and pemetrexed in patients with advanced NSCLC [HR 0.232 (95% CI: 0.055-0.986), P=0.039].

CONCLUSIONS

These results demonstrate that the new hydration protocol comprising supplementation with magnesium without furosemide could prevent the nephrotoxicity induced by cisplatin and pemetrexed without affecting the treatment outcome.

The use of intravenous colistin among children in the United States: results from a multicenter, case series

BACKGROUND

A rapid increase in multidrug-resistant Gram-negative infections has led to a reemergence of colistin use globally. Although it is well described among adults, colistin use and its associated toxicities in children are poorly understood. We report findings from the largest case series of pediatric colistin use to date.

METHODS

We queried pediatric infectious diseases specialists from the Emerging Infections Network to identify members who had prescribed intravenous colistin within the past 7 years. We collected relevant demographic and clinical data. Bivariate analyses and multivariable logistic regression were performed.

RESULTS

Two hundred twenty-nine pediatric infectious diseases specialists completed the survey (84% response); 22% had prescribed colistin to children. Among respondents, 92 cases of colistin use from 25 institutions were submitted. The most commonly targeted organisms were multidrug-resistant Pseudomonas (67.4%), multidrug-resistant Acinetobacter -baumanii (11.9%), carbapenemase-producing Enterobacteriaceae (13.0%) and extended-spectrum β-lactamase producing Enterobacteriaceae (5.4%). Development of resistance to colistin was observed in 20.5% of patients. Additional antimicrobial therapy was administered to 84% of patients, and 22% of children experienced nephrotoxicity (not associated with dosage or interval of colistin prescribed). Renal function returned to baseline in all patients. Children aged ≥13 years had approximately 7 times the odds of developing nephrotoxicity than younger children, even after controlling for receipt of additional nephrotoxic agents (odds ratio 7.16; 95% confidence interval: 1.51-14.06; P = 0.013). Four children exhibited reversible neurotoxicity.

CONCLUSIONS

Most pediatric infectious diseases specialists have no experience prescribing colistin. Colistin use in children has been associated primarily with nephrotoxicity and, to a lesser extent, neurotoxicity, both of which are reversible. Emergence of resistance to colistin is concerning.

Aldosterone synthase gene polymorphism and renal histopathologic changes in kidney transplant patients receiving a calcineurin inhibitor

INTRODUCTION

Aldosterone participates in the pathogenesis of calcineurin inhibitor nephrotoxicity (CIN), producing renal vasoconstriction and transforming growth factor beta (TGFß) expression. The objective of this study was to assess aldosterone polymorphisms and relationships to plasma aldosterone levels and the development of renal histological lesions in kidney transplant patients.

MATERIAL AND METHODS

Patients with kidney graft biopsy were divided according to the presence or absence of CIN. We determined aldosterone synthase (AS) -344 T/C and int 2 W/C gene polymorphisms and plasma aldosterone levels. Histological, biochemical and clinical variables were measured.

RESULTS

Calcineurin inhibitor (CI) levels were significantly higher in patients with the int 2 WW genotype than in patients with WC or CC genotypes. There was a greater degree of interstitial fibrosis in patients with int 2 CC genotype. No relationship was found between the different polymorphisms and a higher degree and/or frequency of CIN. There was also no relationship with plasma aldosterone levels.

CONCLUSION

The frequency of the different polymorphisms studied was not related to plasma aldosterone levels or the development of CIN; however, the int 2 CC genotype was related to a greater degree of interstitial fibrosis, whereas the WW genotype was related to higher CI serum levels.

Unusual coexistence of a renal anomaly and germ cell tumor: An embryonal happenstance?

The germ cell lines and kidney develop in close proximity in a similar embronic period. The extragonadal germ cell tumors and horseshoe kidney both are the result of abnormal migration of two germ line cells. Apart from origin, the combined incidence of mediastinal germ cell tumor with renal anomaly is a therapeutic challenge. This case review is an effort to address the various issues ranging from delima in origin to management and follow-up.

Extract of Ferula foetida regel reverses gentamicin-induced nephrotoxicity in rats

Natural products and dietary components have earlier been proven as potential chemoprotective agents, and continuous efforts are in progress to search for such new products. Gentamicin, an aminoglycoside antibiotic, is widely used for treating the infections caused by many gram negative bacteria. However, besides other unwanted effects, the drug causes tubular cell necrosis in the proximal convoluted tubules of nephrons. Unavailability of any remedial measures in the modern medicine for such ailments therefore makes it imperative to screen for natural products that are nephroprotective against such renal impairment. Here in the undertaken study, we have tested nephroprotective effects of Hing (Ferula foetida) extracts on gentamicin-treated rats. As expected, subcutaneous administration of rats with Gentamicin (100 mg/kg) showed significant increase in blood urea nitrogen (BUN), serum creatinine and thiobarbituric acid reacting substances (TBARS), as an indication of renal disorder. However, co-administration of methanol soluble and insoluble fractions of Ferula foetida (Hing), to the Gentamicin-treated rats almost showed a complete reversal of the above effects, indicating nephroprotective properties of the herbal drug. This may be an important addition to the list of studies where natural products have been discovered to be chemoprotective.

Commentary on a recent review of lithium toxicity: what are its implications for clinical practice?

A recent paper by McKnight et al. in The Lancet has provided the first formal meta-analysis of the more common adverse reactions to lithium. The authors analyzed 385 studies and focused mainly on the harmful effects of lithium on the kidney, the thyroid and parathyroid glands, body weight, skin and congenital malformations. Their contribution is important and welcome, but as a guide for practice, it needs to be complemented by other relevant observations and individual patient-focused perspectives.The findings from that meta-analysis somewhat underestimate the renal side-effects, and distort to some degree or exclude other adverse effects. The glomerular filtration rate is reduced but not more than 0 to 5 ml/min/year of observation; this may not fully reflect the present state of knowledge. A quarter of patients in the study had abnormalities of the thyroid and/or parathyroid gland, and lithium was found to increase body weight significantly less than did olanzapine. Unfortunately, the authors did not consider the observations from spontaneous reporting systems, which may have changed the picture.We feel that some specific limitations of the study were related to the inclusion of patients regardless of adequacy of treatment, quality of monitoring, drug combinations, age and sex, and stabilization response.

Cardiorenal benefits of early versus late cyclosporine to sirolimus conversion in a rat model

Objective:

To compare the cardiorenal effects of early versus late cyclosporine (CsA) to sirolimus (SRL) conversion, using a novel animal model that mimics these protocols used in the clinical practice, and focusing on blood pressure, heart rate (HR), biochemical data and heart and kidney lipid peroxidation.

Materials and Methods:

The study had five groups. Six male Wistar rats in each group were used during a 9-week study protocol: control, CsA (5 mg/kg/day), SRL (1 mg/kg/day); early conversion and late conversion. Cardiorenal evaluation was assessed by biochemical data, blood pressure, HR, and heart and kidney lipid peroxidation.

Results:

As expected, CsA promoted cardiorenal impairment, viewed by development of hypertension, tachycardia, increased urea, creatine kinase, and glucose levels, as well as heart and kidney oxidative stress. SRL, as expected, promoted less cardiorenal side effects, namely those related with nephrotoxicity. In agreement, both early and late conversions from CsA to SRL produced less side-effects, namely those related to the CsA-induced nephrotoxicity.

Conclusions:

In our model, both early and late CsA to SRL conversion promoted amelioration of the CsA -induced cardiorenal damage. However, early substitution seems to produce more benefits, in particular due to higher improvement of the cardiac profile.

Biological alterations and self-reported symptoms among insecticides-exposed workers in Burkina Faso

Occupationally exposed workers, farm workers and plant protection agents in the Sahel region of Burkina Faso were interviewed to assess adverse health effects of insecticides. The subjects were also examined for changes in both hematological and biochemical parameters. The prevalence of liver and kidney dysfunction was found to be quite high among insecticide applicators, especially among plant protection agents. The prevalence of biochemical alterations seems to be correlated to the frequency of insecticide use. However, no significant differences were found between the hematological parameters among farm workers and plant protection agents. The hematological parameters of all the insecticide applicators were normal. The great majority of insecticide applicators (85%) reported symptoms related to insecticide exposure. The use of insecticides in the agriculture of Burkina Faso is threatening to human health.

Attenuation of gentamycin-induced nephrotoxicity in rats by dietary inclusion of ginger (Zingiber officinale) and turmeric (Curcuma longa) rhizomes

This study sought to investigate the modulatory effects of dietary inclusion of ginger (Zingiber officinale) and turmeric (Curcuma longa) rhizomes on antioxidant status and renal damage induced by gentamycin in rats. Renal damage was induced in albino rats pretreated with dietary inclusion of ginger and turmeric (2% and 4%) by intraperitoneal (i.p.) administration of gentamycin (100 mg/kg body weight) for three days. Assays for renal damage biomarkers (plasma creatinine, plasma urea, blood urea nitrogen and plasma uric acid), malondialdehyde (MDA) content and reduced glutathione (GSH) content as well as renal antioxidant enzymes (catalase, glutathione-S-transferase (GST), glutathione peroxidase (GPx) and superoxide dismutase (SOD)) were carried out. The study revealed significant (p < 0.05) increases in renal damage biomarkers following gentamycin administration with severe alteration in kidney antioxidant status. However, pretreatment with ginger and turmeric rhizome (2% and 4%) prior to gentamycin administration significantly (p < 0.05) protected the kidney and attenuated oxidative stress by modulating renal damage and antioxidant indices. This finding therefore suggests that dietary inclusion of ginger and turmeric rhizomes may protect against gentamycin-induced nephrotoxicity and oxidative stress.

The Role of Magnesium Supplementation in Cisplatin-induced Nephrotoxicity in a Rat Model: No Nephroprotectant Effect

OBJECTIVES

Cisplatin (CP) is used as the commonest drug to treat solid tumors. It is accompanied by a nephrotoxicity side effect. The main objective of this study is to investigate the protective role of magnesium (Mg) supplementation in CP-induced nephrotoxicity in a rat model.

METHODS

Twenty-nine Wistar rats were randomly assigned to four groups (1-4). Groups 1-3 received 20, 80, and 200 mg/kg magnesium sulfate respectively, for 10 days, but on day 3, a single dose of CP (7 mg/kg, i.p.) was also injected. Group 4 (positive control group) received the same regimen of Groups 1-3 except saline instead magnesium sulfate. One week after CP administration, blood samples were obtained and all animals were killed for kidney histopathological investigations.

RESULTS

All CP-treated animals lost weight, and the percentage of weight loss in Group 1 (low dose Mg sulfate treated) was significantly higher compared with the positive control group (Group 4, P < 0.05). The increase in blood urea nitrogen (BUN) and creatinine (Cr) levels in serum in Group 1 were more than those in other groups (P < 0.05). No statistical differences were observed in serum magnesium, nitrite, and total protein levels among the groups. The kidney tissue damage in Groups 1-3 was not significantly different when compared with Group 4. Moreover, the kidney and testis weights in Group 1 were significantly greater than those in the positive control group (P < 0.05).

CONCLUSION

Regarding the BUN and Cr levels in the serum, kidneys weight, and the histopathological study, the low dose of Mg supplementation intensifies kidney toxicity and renal dysfunction in CP-induced nephrotoxicity in the rat model. However, the protective role of Mg with moderate and high doses is not certain.

A brief study of toxic effects of some medicinal herbs on kidney

Increased use of complementary and alternative herbal medicines in the treatment of various diseases.Some herbal therapies may be causes of potential toxicity that may be renal toxicity caused by the ingestion of herbs. The goal of this study is the toxic and beneficial effects of medicinal herbs on renal health by which evidence for benefit or toxicity has been found. Included are nephrotoxicity from aristolochic acid and other components within herbs, herb-drug interactions, heavy metal toxicity in herbs and adulterants during careless preparation of herbal medicine, resulting in adverse renal effects and renal toxicity from contaminants within the extracts. The review aims to provide knowledge and guide to encourage future toxicity studies on the kidney by medicinal herbs.

Nephroprotective action of Peucedanum grande against cadmium chloride induced renal toxicity in Wistar rats

Cadmium is a known industrial pollutant which accumulates in the kidney and its exposure leads to the production of reactive oxygen species (ROS). The present study was carried out to evaluate the protective effects of Peucedanum grande against CdCl2 induced renal toxicity in Wistar rats. Wistar rats were subjected to oral pre-treatment of P. grande (60 and 120 mg/kg b.wt) against the renal toxicity induced by administration of CdCl2 (3mg/kg b.wt). Efficacy of P. grande against the renal toxicity was evaluated in terms of biochemical estimation of antioxidant enzyme activities and histopathological changes. P. grande pretreatment prevented deteriorative effects induced by CdCl2 through a protective mechanism that involved reduction of increased oxidative stress as well as by restoration of histopathological changes against CdCl2 administration.

Protective effect of lycopene on deltamethrin-induced histological and ultrastructural changes in kidney tissue of rats

Deltamethrin is globally used in crop protection and control of malaria and other vector-borne diseases. It has a potent insecticidal activity with an appreciable safety margin. However, a number of studies have demonstrated nephrotoxicity of deltamethrin in mammalian and nonmammalian species. Lycopene, a carotenoid occurring naturally in tomatoes, has attracted considerable attention as an antioxidant. This study was focused on investigating the possible protective effect of coadministration of lycopene on deltamethrin toxicity. In this study, male albino rats were divided into four groups of 10 animals each: group I served as control, which received standard diet; group II received oral administration of deltamethrin (1.28 mg/kg per day) for 30 days; group III received both deltamethrin and lycopene (1 mg/kg per day); group IV received lycopene (1 mg/kg per day). After the experiment, the animals were anesthetized and the cytokine, tumor necrosis factor-α (TNF-α), in the serum was measured; the kidney was taken for histological and ultrastructural studies. Deltamethrin significantly increased the TNF-α. The histopathological examination of kidney showed mild necrotic changes. Ultrastructural changes in renal proximal tubules of deltamethrin-treated group included an increased number and irregular shape of mitochondria with sparse fragmented cristae, serious ultrastructural lesions in renal proximal tubular lining cells, vacuolar degeneration in the epithelial cells, increased number of lysosomes and loss of apical microvilli. In addition, focal segmental thickening and the duplication of glomerular basement membrane and podocyte changes were observed. Histopathological and ultrastructural study showed some protective effect of lycopene on kidney tissues.

Apoptosis and lipid peroxidation in ochratoxin A- and citrinin-induced nephrotoxicity in rabbits

Ochratoxin A (OTA) and citrinin (CIT) are nephrotoxic mycotoxins produced mainly by fungal species Aspergillus ochraceus and Penicillium citrinum, respectively, which have been found to occur together in various food and feed commodities. In the present study, both OTA and CIT were evaluated for their potential to induce oxidative damage by determining lipid peroxidation (LPO) through malondialdehyde (MDA) assay and apoptosis by flow cytometry, gel electrophoresis and renal ultrastructural morphology in rabbits fed with diets containing OTA (0.75 mg/kg feed), CIT (15 mg/kg feed) and OTA + CIT (0.75 and 15 mg/kg feed, respectively) up to 60 days. The concentration of MDA was found significantly higher in OTA and combination-treated groups. OTA and combination-treated groups revealed more apoptotic cells in flow cytometry when compared with the CIT-treated group. Characteristic DNA fragmentation, as evidenced by ladder pattern in electrophoresis appeared in the toxin-treated groups. Ultrastructurally, interstitial cells showed nuclear fragmentation and cytoplasmic blebbing in OTA- and CIT-treated groups; whereas, proximal convoluted tubular epithelial cells, besides interstitial cells, showed nuclear fragmentation in the combined treatment group. The results suggested that low concentrations of OTA and CIT either alone or in combination induced apoptosis in a time-dependent manner and LPO in the rabbit kidney, which appeared to play a major role in the pathogenesis of nephrotoxicity. Furthermore, the interaction of these two nephrotoxic mycotoxins was found to be additive.

Lipid peroxidative damage on Cisplatin exposure and alterations in antioxidant defense system in rat kidneys: a possible protective effect of selenium

Cisplatin (Cis-diamminedichloroplatinum II, CP) is an important chemotherapeutic agent, useful in the treatment of several cancers, but with several side effects such as nephrotoxicity. The present study investigated the possible protective effect of selenium (Se) against CP-induced oxidative stress in the rat kidneys. Male Wistar albino rats were injected with a single dose of cisplatin (7 mg CP/kg b.m., i.p.) and selenium (6 mg Se/kg b.m, as Na₂SeO₃, i.p.), alone or in combination. The obtained results showed that CP increased lipid peroxidation (LPO) and decreased reduced glutathione (GSH) concentrations, suggesting the CP-induced oxidative stress, while Se treatment reversed this change to control values. Acute intoxication of rats with CP was followed by statistically significant decreased activity of antioxidant defense enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and glutathione-S-transferase (GST). Treatment with Se reversed CP-induced alterations of antioxidant defense enzyme activities and significantly prevented the CP-induced kidney damage.

High levels of uranium in groundwater of Ulaanbaatar, Mongolia

Water samples collected from 129 wells in seven of the nine sub-divisions of Ulaanbaatar were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using Clean Lab methods. The levels of many trace elements were found to be low with the average concentrations (ranges in brackets) being 0.9 (<0.1-7.9) μg/L for As; 7.7 (0.12-177) μg/L for Mn; 0.2 (<0.05-1.9)μg/L for Co; 16 (<0.1-686) μg/L for Zn; 0.7 (<0.1-1.8) μg/L for Se; <0.1 (<0.02-0.69) μg/L for Cd; and 1.3 (<0.02-32) μg/L for Pb. The levels of uranium were surprisingly elevated (mean, 4.6 μg/L; range <0.01-57 μg/L), with the values for many samples exceeding the World Health Organization's guideline of 15 μg/L for uranium in drinking water. Local rocks and soils appear to be the natural source of the uranium. The levels of uranium in Ulaanbaatar's groundwater are in the range that has been associated with nephrotoxicity, high blood pressure, bone dysfunction and likely reproductive impairment in human populations. We consider the risk associated with drinking the groundwater with elevated levels of uranium in Ulaanbaatar to be a matter for some public health concern and conclude that the paucity of data on chronic effects of low level exposure is a risk factor for continuing the injury to many people in this city.

Self-medication with nutritional supplements and herbal over-thecounter products

In recent years, the popularity increased for nutritional supplements and herbal products. Prescription drugs, but not herbal therapies are paid by health insurances. They are sold over-the-counter (OTC) on the patients’ own expense. However, there are potential risks of self-medication, e.g. incorrect self-diagnosis, severe adverse reactions, dangerous drug interactions, risk of addiction etc. They are often used by patients at their own discretion without knowledge of and control by their physicians. Certain users are at risk of intoxication. Multiple medications taken by older patients increase the risk for adverse drug reactions, drug-drug interactions, and compliance problems for this age group (polypharmacy). Herbals should be discontinued prior to operations to avoid interactions with anesthetics or anticoagulants. Herbal preparations may also be carcinogenic or interfere with cancer treatments. Pregnant women use various OTC preparations. However, in many cases, it is unclear whether their use is safe for mother or baby. Self-medication with herbals is also largely distributed among anxious and depressive patients, and patients with other conditions and symptoms. The popularity of herbal products has also brought concerns on quality, efficacy and safety. Cases of botanical misidentification, contaminations with heavy metals, pesticides, radioactivity, organic solvents, microbials as well as adulteration with chemical drugs necessitate the establishment of international quality control standards. Hepatotoxic effects have been reported for more than 300 plant species, and some commonly used herbs have been demonstrated to interact with Western medication. Health care professionals have a critical responsibility assessing the self-care ability of their patients. Databases are available for pharmacists with information on action, side effects and toxicities as well as herb-drug interactions. There is a need for established guidelines regarding the correct use of nutritional supplements and herbal OTC preparations (phytovigilance). Physicians, pharmacists, and other health care professionals have to counsel patients and the general public on the benefits and risks associated with herbal drugs. Information centers for consumers and general practitioners are needed, and convincing evidence on safety and efficacy of herbal products has to be demonstrated in placebo-controlled, double blind and randomized clinical trials.

Mechanisms pertaining to arsenic toxicity

Arsenic is an environmental pollutant and its contamination in the drinking water is considered as a serious worldwide environmental health threat. The chronic arsenic exposure is a cause of immense health distress as it accounts for the increased risk of various disorders such as cardiovascular abnormalities, diabetes mellitus, neurotoxicity, and nephrotoxicity. In addition, the exposure to arsenic has been suggested to affect the liver function and to induce hepatotoxicity. Moreover, few studies demonstrated the induction of carcinogenicity especially cancer of the skin, bladder, and lungs after the chronic exposure to arsenic. The present review addresses diverse mechanisms involved in the pathogenesis of arsenic-induced toxicity and end-organ damage.

Tenofovir-associated renal dysfunction in clinical practice: An observational cohort from western India

BACKGROUND

Tenofovir (TDF) is preferred nucleoside reverse transcriptase inhibitors (NRTI) for the treatment of human immunodeficiency virus infection because of its potency and safety. Renal toxicity with TDF use is low and comparable with other NRTI in clinical trials, but there are many case studies and small case series of renal dysfunction with TDF.

MATERIALS AND METHODS

This is an observational longitudinal cohort of patients started on a TDF-based regimen from January 2007 to April 2010. Patients were evaluated at baseline and with every follow-up visit for serum creatinine and calculated creatinine clearance (Cockroft-Gault formula). In addition to this, the patients were also subjected to test for serum potassium, phosphorous and urine examinations as and when indicated. Renal dysfunction was defined as rise in serum creatinine to more than the upper level of normal (>1.2 mg%).

RESULTS

Of 1,271 patients started on a TDF-containing antiretroviral treatment (ART) 83 (6.53%) developed renal dysfunction, of which 79 had impaired serum creatinine and five had Fanconi's syndrome. Renal dysfunction was more common with boosted a protease inhibitor (PI) (9.44%)-based regimen as compared to a non- nucleoside reverse transcriptase inhibitors (NNRTI) (5.01%)-based regimen (P = 0.003). The mean decline in creatinine clearance from baseline was 22.27 ml/min. The median time to develop renal dysfunction was 154 (15-935) days. Serum creatinine returned to normal in all the patients after stopping TDF. Five patients presented with features suggestive of Fanconi's syndrome without alteration in serum creatinine.

CONCLUSION

TDF-based treatment is associated with mild but reversible renal dysfunction. Patients receiving PI/r are at a higher risk of renal dysfunction compared to those receiving NNRTI-based ART. Clinicians should be adviced to have intensive renal monitoring, including creatinine clearance, urine examination, K+ and phosphate levels at baseline and during treatment with TDF.

High-dose green tea polyphenols induce nephrotoxicity in dextran sulfate sodium-induced colitis mice by down-regulation of antioxidant enzymes and heat-shock protein expressions

Previously, we reported that oral feeding of 1% green tea polyphenols (GTPs) aggravated the dextran sulfate sodium (DSS)-induced colitis in mice. In the present study, we assessed the toxicity of 1% GTPs in several organs from normal and DSS-exposed mice. Sixty-two male ICR mice were initially divided into four groups. Non-treated group (group 1, n = 15) was given standard diet and water, GTPs (group 2, n = 15) received 1% GTPs in diet and water, DSS (group 3, n = 15) received diet and 5% DSS in water, and GTPs + DSS group (group 4, n = 17) received 1% GTPs in diet and 5% DSS in water. We found that group 4 significantly increased (P < 0.05) kidney weight, the levels of serum creatinine and thiobarbituric acid-reactive substances in both kidney and liver, as compared with those in group 3. The mRNA expression levels of antioxidant enzymes and heat-shock proteins (HSPs) in group 4 were lower than those of group 3. For instance, heme oxygenase-1 (HO-1), HSP27, and 90 mRNA in the kidney of group 4 were dramatically down-regulated as compared with those of group 3. Furthermore, 1% GTPs diet decreased the expression of HO-1, NAD(P)H:quinone oxidoreductase 1 (NQO1) and HSP90 in kidney and liver of non-treated mice. Taken together, our results indicate that high-dose GTPs diet disrupts kidney functions through the reduction of antioxidant enzymes and heat-shock protein expressions in not only colitis but also non-treated ICR mice.

Amelioration of nitrobenzene-induced nephrotoxicity by the ethanol extract of the herb Euphorbia hirta

BACKGROUND

Euphorbia hirta (L.) (Euphorbiaceae) is a very popular herb amongst practitioners of traditional medicine and used in the treatment of female disorders, respiratory ailments, tumors, jaundice, digestive problems, wounds, etc. We aimed to evaluate the protective effect of E. hirta against nitrobenzene-induced nephrotoxicity in albino rats.

MATERIALS AND METHODS

The nephroprotective activity of the ethanol extract of E. hirta (400 mg/kg body weight) was studied in nitrobenzene-induced albino rats (1000 mg/kg body weight). The activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and the levels of reduced glutathione (GSH), total thiols and vitamin C in the kidney tissues were determined. Histopathologic investigation was performed in the kidney tissue samples.

RESULTS

Nitrobenzene administration significantly (P < 0.01) enhanced the lipid peroxidation and significantly (P < 0.05) depleted the levels of SOD, CAT, GPx, GST, GSH, total thiols and vitamin C. Treatment with the ethanol extract of E. hirta significantly normalized the antioxidant levels. The nephroprotective activity was also supported by histopathologic studies of kidney tissue.

CONCLUSION

The results indicate that the ethanol extract of E. hirta ameliorates renal dysfunction and could be used as an effective protector against nitrobenzene-induced nephrotoxicity, primarily through its antioxidant capacity.

A comparative study pertaining to deleterious effects of diclofenac sodium and meloxicam on kidney tissue in rats

NSAIDs (nonsteroidal anti-inflammatory drugs) are a class of drugs with analgesic, anti-inflammatory, and antipyretic effects. Diclofenac sodium is one of the world's most widely-prescribed NSAIDs. Meloxicam is another NSAID that was approved in the last several years. Treatment with NSAIDs may result in renal damage. Relatively, little is known about comparative nephrotoxicity of NSAIDs. Therefore, the present study was designed to compare the adverse effects of diclofenac sodium and meloxicam on renal tissue in rats. Forty eight Wistar male rats were randomly assigned into 3 groups of 16 animals each. Group C served as normal control and received normal saline. Group D and M received diclofenac sodium (2.3 mg/kg/day) and meloxicam (2.3 mg/kg/day), respectively. After 17 days, all rats were scarified. Their kidneys were then harvested and processed for histological examination. In addition to cellular details, renal tubular count and diameter were assessed with the light microscope. The data were analyzed using SPSS software. We found that the mean number of renal tubules was significantly lower in group D, than in group C. Moreover, the mean renal tubular diameter was significantly higher in group D than in group C. The present study showed that a considerable degree of nephrotoxicity resulted from diclofenac sodium, compared to meloxicam. We suggest that diclofenac sodium can be replaced with meloxicam.

The effects of type 1 IGF receptor inhibition in a mouse model of diabetic kidney disease

OBJECTIVE

We have recently shown increased sensitivity to IGF-I induced signal transduction in kidneys of diabetic mice. Accordingly we investigated the effects of PQ401, a novel diarylurea compound that inhibits IGF1R autophosphorylation in type I diabetes.

METHODS

Control (C) and Diabetic (D) mice were administered PQ401 (CP, DP) or vehicle (C, D) for 3weeks.

RESULTS

CP animals showed a decrease in renal phosphorylated (p-)AKT and p-IGF1R. However, PQ401 had no effect on diabetic state (hyperglycemia, weight loss) or renal disease parameters (hypertrophy, hyperfiltration and albuminuria). Type IV collagen as well as TGF-β mRNA increased in DP and D compared to C. In the CP group renal hypertrophy with fat accumulation in proximal tubuli and increased renal IGF-I, collagen IV and TGF-β mRNA were seen.

CONCLUSIONS

IGF1R inhibition by PQ401 exerted no significant effects on diabetic kidney disease parameters, arguing against a role for IGF-I in the pathogenesis of diabetic kidney disease. However, PQ401 affects normal kidneys, inducing renal hypertrophy as well as collagen and fat accumulation, with increased renal IGF-I mRNA, suggestive of a damage-regeneration process. Therefore, this diarylurea compound is not beneficial in early diabetic kidney disease. Its potential deleterious effects on kidney tissue need to be further investigated.

Clinical and plasma proteomic markers correlating with chronic kidney disease after liver transplantation

Chronic kidney disease (CKD) occurs frequently after liver transplantation (LT) and is associated with significant morbidity and mortality. Thus, there is a pressing need to identify characteristics and biomarkers diagnostic of CKD to enable early diagnosis allowing preemptive interventions, as well as mechanistic insights into the progression from kidney injury to irreversible kidney failure. We analyzed 342 patients who had baseline glomerular filteration rate (GFR) >60 at the time of LT and are now >3 years post-LT. Risk factors for post-LT CKD were compared between three different groups defined by current GFR: >90 (n = 40), 60-90 (n = 146) and <60 (n = 156) mL/min. Age, cyclosporine use and pre-LT GFR were independently associated with new onset CKD. A subset (n = 64) without viral/immune disease or graft dysfunction underwent multianalyte plasma proteomic evaluations for correlation with CKD. Plasma proteomic analysis of two independent cohorts, test (n = 22) and validation (n = 42), identified 10 proteins highly associated with new onset CKD. In conclusion, we have identified clinical characteristics and a unique plasma proteomic signature correlating with new onset CKD after LT. These preliminary results are currently being validated in a prospective, multicenter study to determine if this signature precedes the onset of CKD and resolves with early interventions aimed at preserving kidney function.

Nephroprotective effect of Bauhinia variegata (Linn.) whole stem extract against cisplatin-induced nephropathy in rats

The nephroprotective activity of the ethanolic extract of Bauhinia variegata (Linn.) whole stem against cisplatin-induced nephropathy was investigated by an in vivo method in rats. Acute nephrotoxicity was induced by i.p. injection of cisplatin (7 mg/kg of body weight (b.w.)). Administration of ethanol extract at dose levels of 400 and 200 mg/kg (b.w.) to cisplatin-intoxicated rats for 14 days attenuated the biochemical and histological signs of nephrotoxicity of cisplatin in a dose-dependent fashion. Ethanol extract at 400 mg/kg decreased the serum level of creatinine (0.65 ± 0.09; P<0.001) and urea (32.86 ± 5.88; P<0.001) associated with a significant increase in body weight (7.16 ± 1.10; P<0.001) and urine volume output (11.95 ± 0.79; P<0.05) as compared to the toxic control group. The ethanol extract of B. variegata at 400 mg/kg (b.w.) exhibited significant and comparable nephroprotective potential to that of the standard polyherbal drug cystone. The statistically (one-way-ANOVA followed by Tukey-Kramer multiple comparison) processed results suggested the protective action of B. variegate whole stem against cisplatin-induced nephropathy.

Study of nephrotoxic potential of acetaminophen in birds

The present study was designed to evaluate the effect of acetaminophen on kidneys of birds by comparison with diclofenac that is used as positive control. The birds of Group I served as negative control and received normal saline, whereas Group II birds received diclofenac injection (2.5 mg/kg IM) and Group III birds received acetaminophen injection (10 mg/kg IM) for a period of seven days daily. The birds treated with diclofenac showed severe clinical signs of toxicity accompanied with high mortality and significant increase (P<0.001) in serum creatinine and uric acid concentration. The creatinine and uric acid concentrations were consistent with gross and histopathological findings. The negative control and acetaminophen-treated groups showed no adverse clinical signs, serum creatinine and uric acid concentrations were normal, and no gross or histopathological changes in kidneys were observed. Thus, it was concluded that acetaminophen can be used for treatment in birds without any adverse effect on kidneys.

Acetaminophen-induced Hepato- and Nephrotoxicity and Amelioration by Silymarin and Terminalia chebula in Rats

Experimental study was conducted to evaluate the hepato- and renoprotective effect of silymarin and Terminalia chebula against experimentally-induced acetaminophen (APAP) toxicity in rats. Oral administration of APAP @ 500 mg/kg for 1 to 3 days to all the four groups (six rats in each) resulted in significant elevation of serum triglycerides, total cholesterol, blood urea nitrogen, serum creatinine, and aspartate transaminase activity. Post-treatment with silymarin @ 25 mg/kg and T. chebula 125 mg/kg in groups 2 and 3 and their combination to group 4 from day 4 to 14 has significantly reversed the alterations of above said markers and offered better protection. The results of the study enunciated that silymarin and T. chebula exhibit good hepato- and nephro-protection against APAP toxicity.

Protective Effect of Bauhinia purpurea on Gentamicin-induced Nephrotoxicity in Rats

The present study was undertaken to evaluate the ethanol extract of leaves of Bauhinia purpurea and unripe pods of Bauhinia purpurea for its protective effects on gentamicin-induced nephrotoxicity in rats. Nephrotoxicity was induced in Wistar rats by intraperitoneal administration of gentamicin 100 mg/kg/d for eight days. Effect of concurrent administration of ethanol extract of leaves of Bauhinia purpurea and unripe pods of Bauhinia purpurea at a dose of 300 mg/kg/d given by oral route was determined using serum creatinine, serum uric acid, blood urea nitrogen and serum urea as indicators of kidney damage. The study groups contained six rats in each group. It was observed that the ethanol extract of leaves of Bauhinia purpurea and unripe pods of Bauhinia purpurea significantly protect rat kidneys from gentamicin-induced histopathological changes. Gentamicin-induced glomerular congestion, blood vessel congestion, epithelial desquamation, accumulation of inflammatory cells and necrosis of the kidney cells were found to be reduced in the groups receiving the leaf and unripe pods extract of Bauhinia purpurea along with gentamicin. The extracts also normalized the gentamicin-induced increase in serum creatinine, serum uric acid and blood urea nitrogen levels. This is also evidenced by the histopathological studies.

Comparative nephrotoxicity of Cisplatin and nedaplatin: mechanisms and histopathological characteristics

The antineoplastic platinum complexes cisplatin and its analogues are widely used in the chemotherapy of a variety of human malignancies, and are especially active against several types of cancers. Nedaplatin is a second-generation platinum complex with reduced nephrotoxicity. However, their use commonly causes nephrotoxicity due to a lack of tumor tissue selectivity. Several recent studies have provided significant insights into the molecular and histopathological events associated with nedaplatin nephrotoxicity. In this review, we summarize findings concerning the renal histopathology and molecular pathogenesis induced by antineoplastic platinum complexes, with a particular focus on the comparative nephrotoxicity of cisplatin and nedaplatin in rats.

Desferrithiocin analogue iron chelators: iron clearing efficiency, tissue distribution, and renal toxicity

The current solution to iron-mediated damage in transfusional iron overload disorders is decorporation of excess unmanaged metal, chelation therapy. The clinical development of the tridentate chelator deferitrin (1, Table 1) was halted due to nephrotoxicity. It was then shown by replacing the 4'-(HO) of 1 with a 3,6,9-trioxadecyloxy group, the nephrotoxicity could be ameliorated. Further structure-activity relationship studies have established that the length and the position of the polyether backbone controlled: (1) the ligand's iron clearing efficiency (ICE), (2) chelator tissue distribution, (3) biliary ferrokinetics, and (4) tissue iron reduction. The current investigation compares the ICE and tissue distribution of a series of (S)-4,5-dihydro-2-[2-hydroxy-4-(polyether)phenyl]-4-methyl-4-thiazolecarboxylic acids (Table 1, 3-5) and the (S)-4,5-dihydro-2-[2-hydroxy-3-(polyether)phenyl]-4-methyl-4-thiazolecarboxylic acids (Table 1, 8-10). The three most effective polyether analogues, in terms of performance ratio (PR), defined as mean ICE(primate)/ICE(rodent), are 3 (PR 1.1), 8, (PR 1.5), and 9, now in human trials, (PR 2.2). At the onset of the clinical trial on 9, no data were available for ligand 3 or 8. This is unfortunate, as 3 has many advantages over 9, e.g., the ICE of 3 in rats is 2.5-fold greater than that of 9 and analogue 3 achieves very high levels in the liver, pancreas, and heart, the organs most affected by iron overload. Finally, the impact of 3 on the urinary excretion of kidney injury molecule-1 (Kim-1), an early diagnostic biomarker for monitoring acute kidney toxicity, has been carried out in rats; no evidence of nephrotoxicity was found. Overall, the results suggest that 3 would be a far superior clinical candidate to 9.

Accidental and iatrogenic causes of acute kidney injury

PURPOSE OF REVIEW

Ingestions and iatrogenic administration of drugs are all too common causes of acute kidney injury. This review will discuss these preventable causes of acute kidney injury.

RECENT FINDINGS

Recent studies have examined the pathophysiology of acute kidney injury by several commonly used drugs. These studies have shown that drugs and toxins can cause acute kidney injury by altering renal hemodynamics, direct tubular injury or causing renal tubular obstruction.

SUMMARY

Knowledge of the drugs that cause acute kidney injury and how this injury is manifested can lead to improved diagnosis and treatment with the ultimate goal of prevention.