Urinary System

Cyclosporine A (CsA) is the first choice immunosuppressant used for the prevention of allograft rejection in solid organ transplantation and immune-mediated diseases. Reactive oxygen species-induced oxidative stress and lipid peroxidation are implicated in the pathophysiology of CsA-induced renal injury. In this work, we have studied the effect of a garlic-derived compound, S-allylcysteine (SAC) on CsA-induced nephrotoxicity. CsA-induced nephrotoxicity was assessed in terms of increased activities of serum marker enzymes and levels of kidney markers. CsA administration induced significant elevation in lipid peroxidation along with abnormal levels of enzymic and non-enzymic antioxidants in the kidneys of the rats. SAC administration improved renal function by bringing about a significant decrease in peroxidative levels and increase in antioxidant status. Elevated expressions of inducible nitric oxide synthase (iNOS) and nuclear factor kappa B (NF-κB) due to CsA administration were reduced by SAC treatment. An increase in the expression of matrix metalloproteinase-2 (MMP-2) was evident in CsA-induced groups of rats, which was moderately reduced in SAC treated rats. An increase in the levels of serum constituent's urea, uric acid and creatinine was observed in the CsA-induced rats, which was reduced upon treatment with SAC. These results indicate that SAC has a protective action against CsA-induced nephrotoxicity which is also supported by histopathological studies. A comparative study of the antioxidant vitamin C and SAC is more valuable to assess the efficacy of the drug that can be used for the treatment of nephrotoxicity. Copyright © 2009 John Wiley & Sons, Ltd.

To develop a method for assessing absolute renal function (as well as morphology) in children, using gamma camera imaging of intravenously injected technetium-99m (99mTc) dimercaptosuccinic acid (DMSA). Forty-five children (ages 1 week to 10 years; mean, 2.0 years) were imaged using a planar technique in which not only the appearance but the absolute amount of intravenously administered 99mTc DMSA taken up by the kidneys was calculated for each child and compared with contemporaneous determinations of creatinine clearance. There was a close correlation between the absolute DMSA uptake and creatinine clearance (r = 0.752). Renal function in children, expressed as creatinine clearance, can be accurately estimated by measuring absolute DMSA uptake with planar gamma camera imaging using 99mTc DMSA.

Urin je tečna otpadna materija,koja se dobija filtracijom krvi kroz glomerule bubrega.
Iz tela izlazi kroz mokraćne puteve,procesom koji se naziva uriniranje-mokrenje.
Ispitivanja urina u dijagnostičke svrhe je najstariji laboratorijski postupak.

Alginates isolated from Sargassum vulgare, present a strong antitumor activity, associated with kidney reversible damage, as analysed by histopathology of treated animals. In the present study, the renal alteration mechanisms of S. vulgare alginates were investigated using the isolated perfused rat kidney and the isolated perfused rat mesenteric blood vessel methods. The results showed that the effects of Sargassum vulgare low viscosity (SVLV) alginate were more potent than those of Sargassum vulgare high viscosity (SVHV) alginate in the isolated rat kidney. The SVLV alginate caused considerable changes in renal physiology, as shown by an increase in parameters such as perfusion pressure, renal vascular resistance, glomerular filtration rate, urinary flow and sodium, potassium and chloride excretion and by reduction of chloride tubular transport. The effects of SVHV were weaker than those of SVLV. The effects of SVLV on kidney could be related to direct vascular action as demonstrated with SVLV alginate on mesenteric blood vessels. In conclusion, the Sargassum vulgare alginate altered the renal function parameters evaluated. S. vulgare low viscosity alginate renal effects were more potent than S. vulgare high viscosity alginate. It is suggested that physicochemical differences between SVHV and SVLV could explain the differences found in the results. Copyright © 2007 John Wiley & Sons, Ltd.

Tacrolimus, a cornerstone immunosuppressant, is widely available as a twice-daily formulation (Tacrolimus BID). A once-daily prolonged-release formulation (Tacrolimus QD) has been developed that may improve adherence and impart long-lasting graft protection. This study compared the pharmacokinetics (PK) of tacrolimus in de novo kidney transplant patients treated with Tacrolimus QD or Tacrolimus BID. A 6-week, open-label, randomized comparative study was conducted in centers in Europe and Australia. Eligible patients received Tacrolimus QD or Tacrolimus BID. PK profiles were obtained following the first tacrolimus dose (day 1), and twice under steady-state conditions. As secondary objectives, efficacy and safety parameters were also evaluated. Sixty-six patients completed all PK profiles (34 Tacrolimus QD, 32 Tacrolimus BID). Mean AUC0–24 of tacrolimus on day 1 was approximately 30% lower for Tacrolimus QD than Tacrolimus BID (232 and 361 ng.h/mL, respectively), but was comparable by day 4. There was a good correlation and a similar relationship between AUC0–24 and Cmin for both formulations. Efficacy and safety data were also comparable over the 6-week period. Tacrolimus QD can be administered once daily in the morning on the basis of the same systemic exposure and therapeutic drug monitoring concept as Tacrolimus BID.

The effect of thymoquinone (TQ), the main constituent of the volatile oil of Nigella sativa seeds, on the nephropathy and oxidative stress induced by doxorubicin (DOX) in rats was investigated. A single intravenous injection of DOX (6 mg/kg) induced a severe nephrotic syndrome (after 5 weeks) associated with hypoalbuminemia, hypoproteinemia, elevated serum urea, hyperlipidemia, and a high urinary excretion of protein, albumin and N-acetyl-β-d-glucosaminidase (NAG). In the kidney, DOX induced a significant increase in total triglycerides (TG), total cholesterol (TC), and lipid peroxides and a significant decrease in non-protein sulfhydryl (NPSH) content and catalase (CAT) activity. Treatment of rats with TQ (10 mg/kg per day) supplemented with the drinking water for 5 days before DOX, and daily thereafter, significantly lowered serum urea, TG, and TC. Similarly, TG, TC and lipid peroxides in the kidneys of TQ-treated rats were decreased significantly compared with DOX alone. Moreover, NPSH content and CAT activity in the kidneys of TQ-treated DOX group were significantly elevated compared with DOX alone. Treatment with TQ significantly suppressed DOX-induced proteinuria, albuminuria, and urinary excretion of NAG. The results confirm the involvement of free radicals in the pathogenesis of nephropathy induced by DOX. Likewise, the study demonstrates the high antioxidant potential of TQ and its marked effect on the suppression of DOX-induced nephropathy. The data suggest that TQ might be applicable as a protective agent for proteinuria and hyperlipidemia associated with nephrotic syndrome.

Although inulin clearance measured during constant infusion is still considered the reference method, single-injection of 51Cr-EDTA with subsequent plasma sampling has become the most popular technique for the routine assessment of glomerular filtration rate. Despite the fact that the technique has been in use for 30 years, there are only a few reports of normal values calculated directly from 51Cr-EDTA data and normal ranges have generally been produced by conversions of inulin data. The aim of this study was to measure the variation in total plasma clearance, calculated directly from 51Cr-EDTA measurements, in normal males and females, of Saudi Arabian origin, over a wide range. Altogether, 201 potential kidney donors aged 16-60 years were studied. No statistically significant association of total plasma clearance with age or sex could be demonstrated; however, predictive equations suggesting a small decline in total plasma clearance with age were developed. The figures presented suggest that the reduction in total plasma clearance of 51Cr-EDTA with age is relatively shallow up to the age of at least 60 years and that normal ranges produced by conversion of inulin data may overestimate the decline with age.