Sheep are highly adequate models for human renal diseases because of their many similarities in the histology and physiology of kidney and pathogenesis of kidney diseases. However, the lack of a ...simple method to measure glomerular filtration rate (GFR) limits its use as a model of renal diseases. Hence, we aimed to develop a simple method to measure GFR based on the plasma clearance of iohexol by assessing different pharmacokinetic models: (a) CL2: two-compartment (samples from 15 to 420 min; reference method); (b) CL1: one-compartment (samples from 60 to 420 min); (c) CLlf: CL1 adjusted by a correction formula and (d) SM: simplified CL2 (15 to 300 min). Specific statistics of agreement were used to test the models against CL2. The agreement between CL1 and CL2 was low, but both CL1f and SM showed excellent agreement with CL2, as indicated by a total deviation index of ~5–6%, a concordance correlation of 0.98–0.99% and a coverage probability of 99–100%, respectively. Hence, the SM approach is preferable due to a reduced number of samples and shorter duration of the procedure; two points that improve animal management and welfare.
The determination of renal function is crucial in patients with type 2 diabetes (T2DM), a population at risk for chronic kidney disease (CKD). Glomerular filtration rate (GFR) can be measured (mGFR) ...with gold standard methods or estimated (eGFR) with formulas. Since 1957, when Effersoe published the first formula, more than 50 equations have been developed to estimate GFR. In this review, we examined the studies that compared mGFR and eGFR in patients with T2DM to analyze the performance of those formulae in this population. In cross-sectional studies, the average error of eGFR was ±30% of mGFR. Thus, in a patient with mGFR of 60 mL/min, eGFR may vary from 42 to 78 mL/min. Moreover, many patients were misclassified according to CKD stages. Formulas failed to detect glomerular hyperfiltration. In longitudinal studies, eGFR poorly reflected real GFR decline over time. All studies showed that eGFR decline was slower than mGFR decline. Notably, no major improvement in accuracy and precision has been observed since 1957 despite the use of cystatin-c. Thus, formulas are not reliable indicators of GFR in patients with T2DM. In clinical studies, where GFR is the main outcome measure of the study, eGFR should be avoided.
Immunosuppressive regimens based on low doses of cyclosporine A (CsA) or tacrolimus (TAC) may improve short-term outcome after kidney transplantation (KT), but the optimal immunosuppressive protocol ...is currently unknown.
This study compared the 24-month efficacy and safety of two immunosuppressive regimens using reduced calcineurin inhibitors (CNIs) exposure with standard dosage of CsA in 240 patients who were randomized into three groups: group A (n=80): Thymoglobulin, CsA (4 mg/kg twice daily) plus azathioprine (1.5 mg/kg once daily); group B (n=80): basiliximab, CsA (2 mg/kg/ twice daily) plus mycophenolate mofetil (MMF; 1 g twice daily); and group C (n=80): basiliximab, TAC (0.05 mg/kg/ twice daily) plus MMF (1 g twice daily). Steroid administration was identical for all groups.
A significantly better creatinine clearance at 12 months, estimated by Cockcroft-Gault (57+/-12, 65.2+/-20, 73.5+/-27 ml/min, P=0.044), the Jelliffe-2 (51.5+/-16, 56+/-19, 59.4+/-19 ml/min/1.73 m2, P=0.041) and the Modification of Diet in Renal Disease equations (53+/-17, 58.5+/-20, 61.6+/-22 ml/min/1.73 m2, P=0.035), was observed in group C compared with group A. No significant differences were observed between groups B and C. The incidence of biopsy-proven acute rejection was similar between groups (15%, 13.8%, and 16.3%). In addition, patient and graft survival at 24 months were not different between groups. Adverse effects were similar among groups, but cytomegalovirus infections was significantly higher in group A (41% vs. 20% vs. 25%; P=0.008).
Immunosuppressive regimens with reduced CNI exposure provide similar preservation of renal function compared with standard dose of CsA after KT and do not lead to underimmunosuppression.
Abstract
Chronic kidney disease (CKD) in patients with diabetes mellitus (DM) is a major problem of public health. Currently, many of these patients experience progression of cardiovascular and renal ...disease, even when receiving optimal treatment. In previous years, several new drug classes for the treatment of type 2 DM have emerged, including inhibitors of renal sodium–glucose co-transporter-2 (SGLT-2) and glucagon-like peptide-1 (GLP-1) receptor agonists. Apart from reducing glycaemia, these classes were reported to have other beneficial effects for the cardiovascular and renal systems, such as weight loss and blood pressure reduction. Most importantly, in contrast to all previous studies with anti-diabetic agents, a series of recent randomized, placebo-controlled outcome trials showed that SGLT-2 inhibitors and GLP-1 receptor agonists are able to reduce cardiovascular events and all-cause mortality, as well as progression of renal disease, in patients with type 2 DM. This document presents in detail the available evidence on the cardioprotective and nephroprotective effects of SGLT-2 inhibitors and GLP-1 analogues, analyses the potential mechanisms involved in these actions and discusses their place in the treatment of patients with CKD and DM.
Estimated GFR: time for a critical appraisal Porrini, Esteban; Ruggenenti, Piero; Luis-Lima, Sergio ...
Nature reviews. Nephrology,
03/2019, Letnik:
15, Številka:
3
Journal Article
Recenzirano
Since 1957, over 70 equations based on creatinine and/or cystatin C levels have been developed to estimate glomerular filtration rate (GFR). However, whether these equations accurately reflect renal ...function is debated. In this Perspectives article, we discuss >70 studies that compared estimated GFR (eGFR) with measured GFR (mGFR), involving ~40,000 renal transplant recipients and patients with chronic kidney disease (CKD), type 2 diabetes mellitus or polycystic kidney disease. Their results show that eGFR often differed from mGFR by ±30% or more, that eGFR values incorrectly staged CKD in 30-60% of patients, and that eGFR and mGFR gave different rates of GFR decline. Errors were unpredictable, and comparable for equations based on creatinine and/or cystatin C. We argue, therefore, that the persistence of these errors (despite intensive research) suggests that the problem lies with using creatinine and/or cystatin C as markers of renal function, rather than with the mathematical methods used for GFR estimation.
Background: Switching to cyclosporin A may result in a reversion of tacrolimus-induced diabetes mellitus. However, mechanisms underlying such a reversion are still unknown. Methods: Obese Zucker rats ...were used as a model for tacrolimus-induced diabetes mellitus. A cohort of 44 obese Zucker rats received tacrolimus for 11 days (0.3 mg/kg/day) until diabetes development; then, (a) 22 rats were euthanized at day 12 and were used as a reference group (tacrolimus-day 12), and (b) 22 rats on tacrolimus were shifted to cyclosporin (2.5 mg/kg/day) for 5 days (tacrolimus-cyclosporin). An additional cohort of 22 obese Zucker rats received the vehicle for 17 days and was used as a control group. All animals underwent an intraperitoneal glucose tolerance test at the end of the study. Results: β-Cell proliferation, apoptosis and Ins2 gene expression were evaluated. Compared to rats in tacrolimus-day 12 group, those in tacrolimus-cyclosporin group showed a significant improvement in blood glucose levels in all assessment points in intraperitoneal glucose tolerance test. Diabetes decreased from 100% in tacrolimus-day-12 group to 50% in tacrolimus-cyclosporin group. Compared to tacrolimus-day-12 group, rats in tacrolimus-cyclosporin group showed an increased β-cell proliferation, but such an increase was lower than in rats receiving the vehicle. Ins2 gene expressions in rats receiving tacrolimus-cyclosporin and rats receiving the vehicle were comparable. Conclusion: An early switch from tacrolimus to cyclosporin in tacrolimus-induced diabetes mellitus resulted in an increased β-cell proliferation and reversion of diabetes in 50% of cases.
El cambio a ciclosporinaA podría revertir la diabetes inducida por tacrolimus. Sin embargo, los mecanismos de esta reversibilidad se desconocen.
Usamos como modelo de diabetes inducida por tacrolimus ...las ratas Zucker obesas. Un grupo de 44 ratas Zucker obesas fue tratado con tacrolimus durante 11días (0,3mg/kg/día) hasta que desarrollaron diabetes; posteriormente, a)22 fueron sacrificadas a día 12 como grupo referencia (tacrolimus-d12), y b)en otras 22 el tacrolimus fue reemplazado por ciclosporina (2,5mg/kg/día) durante 5días (tacrolimus-ciclosporina). Veintidós ratas Zucker obesas recibieron vehículo durante 17días (grupo control). A todos los animales se les realizó una sobrecarga intraperitoneal de glucosa al final del experimento.
Se analizó la proliferación de la célulaβ, la apoptosis y la expresión del gen Ins2. En el grupo tacrolimus-ciclosporina, los niveles de glucemia mejoraron significativamente en cada punto del test intraperitoneal de glucosa comparados con el grupo tacrolimus-d12. La diabetes se redujo del 100% en los tacrolimus-d12 hasta el 50% en tacrolimus-ciclosporina. La proliferación de las células β en tacrolimus-ciclosporina se incrementó en comparación con tacrolimus-d12, pero fue menor que en los tratados con vehículo. La expresión génica de Ins2 en tacrolimus-ciclosporina fue comparable a los tratados con el vehículo.
El cambio temprano de tacrolimus por ciclosporina en la diabetes inducida por tacrolimus incrementa la proliferación de la célulaβ y revierte la diabetes en un 50% de los casos.
Switching to cyclosporinA may result in a reversion of tacrolimus-induced diabetes mellitus. However, mechanisms underlying such a reversion are still unknown.
Obese Zucker rats were used as a model for tacrolimus-induced diabetes mellitus. A cohort of 44 obese Zucker rats received tacrolimus for 11 days (0.3mg/kg/day) until diabetes development; then: (a)22 rats were euthanized at day 12 and were used as a reference group (tacrolimus-day 12), and (b)22 rats on tacrolimus were shifted to cyclosporin (2.5mg/kg/day) for 5 days (tacrolimus-cyclosporin). An additional cohort of 22 obese Zucker rats received the vehicle for 17 days and were used as a control group. All animals underwent an intraperitoneal glucose tolerance test at the end of the study.
β-cell proliferation, apoptosis and Ins2 gene expression were evaluated. Compared to rats in tacrolimus-day 12 group, those in tacrolimus-cyclosporin group showed a significant improvement in blood glucose levels in all assessment points in intraperitoneal glucose tolerance test. Diabetes decreased from 100% in tacrolimus-day 12 group to 50% in tacrolimus-cyclosporin group. Compared to tacrolimus-day 12 group, rats in tacrolimus-cyclosporin group showed an increased β-cell proliferation, but such an increase was lower than in rats receiving the vehicle. Ins2 gene expressions in rats receiving tacrolimus-cyclosporin and rats receiving the vehicle were comparable.
An early switch from tacrolimus to cyclosporin in tacrolimus-induced diabetes mellitus resulted in an increased β-cell proliferation and reversion of diabetes in 50% of cases.
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