Kefir administration reduced progression of renal injury in STZ-diabetic rats by lowering oxidative stress

This study aimed at assessing the effects of Kefir, a probiotic fermented milk, on oxidative stress in diabetic animals. the induction of diabetes was achieved in adult male Wistar rats using streptozotocin (STZ). the animals were distributed into four groups as follows: control (CTL); control Kefir (CTLK); diabetic (DM) and diabetic Kefir (DMK). Starting on the 5th day of diabetes, Kefir was administered by daily gavage at a dose of 1.8 mL/day for 8 weeks. Before and after Kefir treatment, the rats were placed in individual metabolic cages to obtain blood and urine samples to evaluate urea, creatinine, proteinuria, nitric oxide (NO), thiobarbituric acid reactive substances (TBARS) and C-reactive protein (CRP). After sacrificing the animals, the renal cortex was removed for histology, oxidative stress and NOS evaluation. When compared to CTL rats, DM rats showed increased levels of glycemia, plasmatic urea, proteinuria, renal NO, superoxide anion, TBARS, and plasmatic CRP; also demonstrated a reduction in urinary urea, creatinine, and NO. However, DMK rats showed a significant improvement in most of these parameters. Despite the lack of differences observed in the expression of endothelial NO synthase (eNOS), the expression of inducible NO synthase (iNOS) was significantly lower in the DMK group when compared to DM rats, as assessed by Western blot analysis. Moreover, the DMK group presented a significant reduction of glycogen accumulation within the renal tubules when compared to the DM group. These results indicate that Kefir treatment may contribute to better control of glycemia and oxidative stress, which is associated with the amelioration of renal function, suggesting its use as a non-pharmacological adjuvant to delay the progression of diabetic complications. (C) 2014 Elsevier Inc. All rights reserved.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundacao de Apoio a Universidade Federal de São Paulo (FAP-Unifesp)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Dept Med, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pathol, BR-04023900 São Paulo, BrazilUniv São Paulo, Coll Publ Hlth, Dept Nutr, São Paulo, BrazilUniv São Paulo, Dept Biochem & Pharmaceut Technol, São Paulo, BrazilUniv São Paulo, Dept Nephrol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Med, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pathol, BR-04023900 São Paulo, BrazilWeb of Scienc

Renal function evaluation in patients with American Cutaneous Leishmaniasis after specific treatment with pentavalent antimonial

Background\ud Renal evaluation studies are rare in American Cutaneous Leishmaniasis (ACL). The aim of this study is to investigate whether specific treatment reverts ACL-associated renal dysfunction.\ud \ud Methods\ud A prospective study was conducted with 37 patients with ACL. Urinary concentrating and acidification ability was assessed before and after treatment with pentavalent antimonial.\ud \ud Results\ud The patients mean age was 35.6 ± 12 years and 19 were male. Before treatment, urinary concentrating defect (U/Posm <2.8) was identified in 27 patients (77%) and urinary acidification defect in 17 patients (46%). No significant glomerular dysfunction was observed before and after specific ACL treatment. There was no reversion of urinary concentrating defects, being observed in 77% of the patients before and in 88% after treatment (p = 0.344). Urinary acidification defect was corrected in 9 patients after treatment, reducing its prevalence from 40% before to only 16% after treament, (p = 0.012). Microalbuminuria higher than 30 mg/g was found in 35% of patients before treatment and in only 8% after treatment. Regarding fractional excretion of sodium, potassium, calcium, phosphorus and magnesium, there was no significant difference between pre and post-treatment period.\ud \ud Conclusion\ud As previously described, urinary concentrating and acidification defects were found in an important number of patients with ACL. Present results demonstrate that only some patients recover urinary acidification capacity, while no one returned to normal urinary concentration capacity.This research was supported by the Brazilian National Council for Scientific and Technological Development (CNPq). The desmopressin acetate was provided by Ferring of Brazil

Renal function evaluation in patients with American Cutaneous Leishmaniasis after specific treatment with pentavalent antimonial

Background\ud Renal evaluation studies are rare in American Cutaneous Leishmaniasis (ACL). The aim of this study is to investigate whether specific treatment reverts ACL-associated renal dysfunction.\ud \ud Methods\ud A prospective study was conducted with 37 patients with ACL. Urinary concentrating and acidification ability was assessed before and after treatment with pentavalent antimonial.\ud \ud Results\ud The patients mean age was 35.6 ± 12 years and 19 were male. Before treatment, urinary concentrating defect (U/Posm <2.8) was identified in 27 patients (77%) and urinary acidification defect in 17 patients (46%). No significant glomerular dysfunction was observed before and after specific ACL treatment. There was no reversion of urinary concentrating defects, being observed in 77% of the patients before and in 88% after treatment (p = 0.344). Urinary acidification defect was corrected in 9 patients after treatment, reducing its prevalence from 40% before to only 16% after treament, (p = 0.012). Microalbuminuria higher than 30 mg/g was found in 35% of patients before treatment and in only 8% after treatment. Regarding fractional excretion of sodium, potassium, calcium, phosphorus and magnesium, there was no significant difference between pre and post-treatment period.\ud \ud Conclusion\ud As previously described, urinary concentrating and acidification defects were found in an important number of patients with ACL. Present results demonstrate that only some patients recover urinary acidification capacity, while no one returned to normal urinary concentration capacity.This research was supported by the Brazilian National Council for Scientific and Technological Development (CNPq). The desmopressin acetate was provided by Ferring of Brazil

Role of phosphodiesterase inhibitor(sildenafil) in lithium-induced diabetes insipidus

Os pacientes que usam lítio (Li) para tratamento do transtorno bipolar freqüentemente apresentam poliúria e deficiência de concentração urinária, sintomas do Diabetes Insipidus nefrogênico (DIN). Animais tratados com Li apresentam baixos níveis de produção de adenosina monofosfato cíclico (AMPc) em resposta ao hormônio antidiurético (HAD). O Sildenafil (Sil), um inibidor da fosfodiesterase 5 (PDE5), eleva os níveis intracelulares de guanosina monofosfato cíclico (GMPc), levando a inserção de aquaporina 2 (AQP2) na membrana plasmática das células do ducto coletor. Portanto, inibidores de PDE podem promover a inserção de AQP2 na membrana plasmática mesmo sem a ativação do receptor de HAD, indicando a participação de uma via alternativa mediada pelo GMPc. Nós investigamos o efeito do Sil na expressão renal das proteínas de membrana AQP2, UT-A1, NKCC2, NHE3, P-ENaC em ratos com DIN induzido pelo Li. Ratos Wistar foram divididos nos seguintes grupos: grupo controle, recebendo dieta alimentar normal durante quatro semanas; grupo Li, recebendo dieta alimentar normal com 40 mmol Li por quilo de dieta durante quatro semanas; grupo Li + Sil, recebendo dieta alimentar normal com 40 mmol Li por quilo de dieta durante quatro semanas e 200 mg por quilo de dieta de Sil a partir da segunda semana; grupo Sil, recebendo dieta alimentar normal durante a primeira semana e a partir da segunda semana recebendo dieta normal com 200 mg de Sil por quilo de dieta. Os animais do grupo Li desenvolveram poliúria, diminuição da osmolalidade urinária e diminuição da expressão da AQP2. No grupo Li+Sil, o Sil foi capaz de reverter parcialmente a poliúria, diminuir o clearance de água livre, aumentar a osmolalidade urinária e aumentar a expressão da AQP2. A expressão de UTA1 foi completamente normalizada com o tratamento com Sil. A expressão das proteínas NKCC2 e NHE3 apresentaram-se aumentadas no grupo tratado com Li, e o Sil não foi capaz de reverter tal alteração. Além disso, o tratamento com Sil reverteu completamente o aumento da resistência vascular renal. Assim, concluímos que o tratamento com Sil em ratos com DIN melhora a poliúria, aumenta a smolalidade urinária e diminui o clearance de água livre pelo aumento da expressão de AQP2 e UT-A1. O tratamento com Sil pode ser benéfico para pacientes que sofrem com DIN induzida pelo Li.Patients taking lithium to treat bipolar disorder often present polyuria and urinary concentrating defect. In addition, lithium-treated animals present lower cyclic adenosine monophosphate production in response to vasopressin. Sildenafil (Sil), a phosphodiesterase 5 (PDE5) inhibitor, elevates intracellular cyclic guanosine monophosphate (cGMP) levels, leading to plasma membrane accumulation of aquaporin 2 (AQP2). Therefore, PDE inhibitors might induce AQP2 membrane insertion even without vasopressin receptor activation by activating a parallel cGMP-mediated signal transduction pathway. We investigated the effect of sildenafil on renal expression of AQP2, UT-A1, sodium/hydrogen exchanger (NHE3), type 1 bumetanide-sensitive Na-K-2Cl cotransporter (NKCC2), and the epithelial sodium channel alpha subunit (P-ENaC). Wistar rats received lithium (40 mmol/kg food) or not for 4 weeks (Li or control), some rats also receiving sildenafil (200 mg/kg food) in weeks 2-4, with or without lithium (Li+Sil or Sil). In Li+Sil rats, urine output was markedly lower, as was water free clearance, whereas urine osmolality was higher. Semiquantitative immunoblotting revealed the following: AQP2 expression was partially normalized; UT-A1 expression was completely normalized; expression of NKCC2 and NHE3 was significantly higher in Li rats (although not significantly different between Li+Sil rats and Li rats); and P-ENaC protein expression was unaltered in all groups. Sildenafil treatment completely reversed the lithium-induced increase in renal vascular resistance. In conclusion, sildenafil treatment of lithium-induced nephrogenic diabetes insipidus (NDI) improves polyuria, increases urinary osmolality, and decreases free water clearance via upregulation of renal AQP2 and UT-A1. Sildenafil treatment could be beneficial in patients with lithium-induced NDI

Sildenafil action in lithium-induced NDI: intracellular pathway

Os pacientes que usam lítio (Li) para tratamento do transtorno bipolar frequentemente apresentam poliúria e deficiência de concentração urinária, sintomas do Diabetes Insipidus Nefrogênico (DIN). Animais tratados com Li apresentam baixos níveis de produção de adenosina monofosfato cíclico (AMPc) em resposta ao hormônio antidiurético (HAD). O Sildenafil (Sil), um inibidor da fosfodiesterase 5 (PDE5), eleva os níveis intracelulares de guanosina monofosfato cíclico (GMPc), levando a inserção de aquaporina 2 (AQP2) na membrana plasmática das células do ducto coletor. Portanto, inibidores de PDE podem promover a inserção de AQP2 na membrana plasmática mesmo sem a ativação do receptor de HAD, indicando a participação de uma via alternativa mediada pelo GMPc. Nós investigamos as vias de ação do Sil no tratamento da DIN induzida pelo Li. Ratos Wistar foram divididos nos seguintes grupos: grupo controle, recebendo dieta alimentar normal durante quatro semanas; grupo Li, recebendo dieta alimentar normal com 40 mmol Li por quilo de dieta durante quatro semanas; grupo Li + Sil, recebendo dieta alimentar normal com 40 mmol Li por quilo de dieta durante quatro semanas e 200 mg por quilo de dieta de Sil a partir da segunda semana; grupo Sil, recebendo dieta alimentar normal durante a primeira semana e a partir da segunda semana recebendo dieta normal com 200 mg de Sil por quilo de dieta. Os animais do grupo Li desenvolveram poliúria, diminuição da osmolalidade urinária e diminuição da expressão da AQP2 tanto na fração citoplasmática como de membrana celular e o Sil reverteu essas alterações. Demonstramos ainda que a concentração de GMPc intracelular estava aumentada nos túbulos papilares tratados com Sil. Observamos que a provável via de fosforilação da AQP2 induzida pelo GMPc é pela PKA. Além disso, o tratamento com Sil aumenta a expressão de pCreb, fator de transcrição para ativação do gene da AQP2. Observamos ainda que o Li diminui a expressão de eNOS e o tratamento com Sil normaliza essa diminuição. Assim, concluímos que o tratamento com Sil em ratos com DIN melhora a poliúria aumentando a produção e a inserção de AQP2. O tratamento com Sil pode ser benéfico para pacientes que sofrem com DIN induzido pelo LiPatients taking lithium to treat bipolar disorder often present polyuria and urinary concentrating defect. In addition, lithium-treated animals present lower cyclic adenosine monophosphate production in response to vasopressin. Sildenafil (Sil), a phosphodiesterase 5 (PDE5) inhibitor, elevates intracellular cyclic guanosine monophosphate (cGMP) levels, leading to plasma membrane accumulation of aquaporin 2 (AQP2). Therefore, PDE inhibitors might induce AQP2 membrane insertion even without vasopressin receptor activation by activating a parallel cGMP-mediated signal transduction pathway. We investigated Sil pathways of action in rats with lithium-induced nephrogenic Diabetes Insipidus (NDI). Wistar rats received lithium (40 mmol/kg food) or not for 4 weeks (Li or control), some rats also receiving sildenafil (200 mg/kg food) in weeks 2-4, with or without lithium (Li+Sil orSil). Animals in Li group developed polyuria, decreased urinary osmolality and decreased expression of AQP2 in both the cytoplasmic fraction and the cell membrane and Sil reversed these changes. We also demonstrated that intracellular cGMP concentration was increased in papillary tubules treated with Sil. We found that PKA may be involved in the pathway of cGMP induced AQP2 phosphorylation. In addition, Sil treatment increases Creb phosphorylation. Creb phosphorylation, acts as AQP2 gene transcription factor. We also observed that Li decreases eNOS expression and treatment with Sil normalizes this alteration. We conclude that Sil treatment improves polyuria by increasing production and insertion of AQP2. Sil treatment may be beneficial to patients suffering from induced DIN L

Reduced hippocampal manganese-enhanced MRI (MEMRI) signal during pilocarpine-induced status epilepticus: Edema or apoptosis?

Manganese-enhanced MRI (MEMRI) has been considered a surrogate marker of Ca+2 influx into activated cells and tracer of neuronal active circuits. However, the induction of status epilepticus (SE) by kainic acid does not result in hippocampal MEMRI hypersignal, in spite of its high cell activity. Similarly, short durations of status (5 or 15 min) induced by pilocarpine did not alter the hippocampal MEMRI, while 30 min of SE even reduced MEMRI signal Thus, this study was designed to investigate possible explanations for the absence or decrease of MEMRI signal after short periods of SE. We analyzed hippocampal caspase-3 activation (to evaluate apoptosis), T-2 relaxometry (tissue water content) and aquaporin 4 expression (water-channel protein) of rats subjected to short periods of pilocarpine-induced SE. for the time periods studied here, apoptotic cell death did not contribute to the decrease of the hippocampal MEMRI signal. However, T-2 relaxation was higher in the group of animals subjected to 30 min of SE than in the other SE or control groups. This result is consistent with higher AQP-4 expression during the same time period. Based on apoptosis and tissue water content analysis, the low hippocampal MEMRI signal 30 min after SE can potentially be attributed to local edema rather than to cell death. (C) 2014 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, UNIFESP, Dept Fisiol, BR-0402306 São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Neurol & Neurocirurgia, BR-0402306 São Paulo, BrazilUniv São Paulo, Fac Med, Dept Nefrol, São Paulo, BrazilUniv São Paulo, IFSC, Ctr Imagens & Espectroscopia Vivo Ressonancia Mag, BR-13566590 Sao Carlos, SP, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Fisiol, BR-0402306 São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Dept Neurol & Neurocirurgia, BR-0402306 São Paulo, BrazilFAPESP: 05/56663-1FAPESP: 07/52911-6Web of Scienc

Atorvastatin Prevents the Downregulation of Aquaporin-2 Receptor After Bilateral Ureteral Obstruction and Protects Renal Function in a Rat Model

OBJECTIVE To assess the effects of atorvastatin (ATORV) on renal function after bilateral ureteral obstruction (BUO), measuring inulin clearance and its effect on renal hemodynamic, filtration, and inflammatory response, as well as the expression of Aquaporin-2 (AQP2) in response to BUO and after the release of BUO. METHODS Adult Munich-Wistar male rats were subjected to BUO for 24 hours and monitored during the following 48 hours. Rats were divided into 5 groups: sham operated (n = 6); sham + ATORV (n = 6); BUO (n = 6); BUO + ATORV (10 mg/kg in drinking water started 2 days before BUO [n = 5]; and BUO + ATORV (10 mg/kg in drinking water started on the day of the release of BUO [n = 5]). We measured blood pressure (BP, mm Hg); inulin clearance (glomerular filtration rate [GFR]; mL/min/100 g); and renal blood flow (RBF, mL/min, by transient-time flowmeter). Inflammatory response was evaluated by histologic analysis of the interstitial area. AQP2 expression was evaluated by electrophoresis and immunoblotting. RESULTS Renal function was preserved by ATORV treatment, even if initiated on the day of obstruction release, as expressed by GFR, measured by inulin clearance. Relative interstitial area was decreased in both BUO + ATORV groups. Urine osmolality was improved in the ATORV-treated groups. AQP2 protein expression decreased in BUO animals and was reverted by ATORV treatment. CONCLUSION ATORV administration significantly prevented and restored impairment in GFR and renal vascular resistance. Furthermore, ATORV also improved urinary concentration by reversing the BUO-induced downregulation of AQP2. These findings have significant clinical implication in treating obstructive nephropathy. UROLOGY 80: 485.e15-485.e20, 2012. (c) 2012 Elsevier Inc

Vitamin D deficiency aggravates nephrotoxicity, hypertension and dyslipidemia caused by tenofovir: role of oxidative stress and renin-angiotensin system.

Vitamin D deficiency (VDD) is prevalent among HIV-infected individuals. Vitamin D has been associated with renal and cardiovascular diseases because of its effects on oxidative stress, lipid metabolism and renin-angiotensin-aldosterone system (RAAS). Tenofovir disoproxil fumarate (TDF), a widely used component of antiretroviral regimens for HIV treatment, can induce renal injury. The aim of this study was to investigate the effects of VDD on TDF-induced nephrotoxicity. Wistar rats were divided into four groups: control, receiving a standard diet for 60 days; VDD, receiving a vitamin D-free diet for 60 days; TDF, receiving a standard diet for 60 days with the addition of TDF (50 mg/kg food) for the last 30 days; and VDD+TDF receiving a vitamin D-free diet for 60 days with the addition of TDF for the last 30 days. TDF led to impaired renal function, hyperphosphaturia, hypophosphatemia, hypertension and increased renal vascular resistance due to downregulation of the sodium-phosphorus cotransporter and upregulation of angiotensin II and AT1 receptor. TDF also increased oxidative stress, as evidenced by higher TBARS and lower GSH levels, and induced dyslipidemia. Association of TDF and VDD aggravated renovascular effects and TDF-induced nephrotoxicity due to changes in the redox state and involvement of RAAS

Sildenafil reduces polyuria in rats with lithium-induced NDI

Sanches TR, Volpini RA, Massola Shimizu MH, de Bragan a AC, Oshiro-Monreal F, Seguro AC, Andrade L. Sildenafil reduces polyuria in rats with lithium-induced NDI. Am J Physiol Renal Physiol 302: F216-F225, 2012. First published October 12, 2011; doi:10.1152/ajprenal.00439.2010.-Lithium (Li)-treated patients often develop urinary concentrating defect and polyuria, a condition known as nephrogenic diabetes insipidus (NDI). In a rat model of Li-induced NDI, we studied the effect that sildenafil (Sil), a phosphodiesterase 5 (PDE5) inhibitor, has on renal expression of aquaporin-2 (AQP2), urea transporter UT-A1, Na(+)/H(+) exchanger 3 (NHE3), Na(+)-K(+)-2Cl(-) cotransporter (NKCC2), epithelial Na channel (ENaC; alpha-, beta-, and gamma-subunits), endothelial nitric oxide synthase (eNOS), and inducible nitric oxide synthase. We also evaluated cGMP levels in medullary collecting duct cells in suspension. For 4 wk, Wistar rats received Li (40 mmol/kg food) or no treatment (control), some receiving, in weeks 2-4, Sil (200 mg/kg food) or Li and Sil (Li+Sil). In Li+Sil rats, urine output and free water clearance were markedly lower, whereas urinary osmolality was higher, than in Li rats. The cGMP levels in the suspensions of medullary collecting duct cells were markedly higher in the Li+Sil and Sil groups than in the control and Li groups. Semiquantitative immunoblotting revealed the following: in Li+Sil rats, AQP2 expression was partially normalized, whereas that of UT-A1, gamma-ENaC, and eNOS was completely normalized; and expression of NKCC2 and NHE3 was significantly higher in Li rats than in controls. Inulin clearance was normal in all groups. Mean arterial pressure and plasma arginine vasopressin did not differ among the groups. Sil completely reversed the Li-induced increase in renal vascular resistance. We conclude that, in experimental Li-induced NDI, Sil reduces polyuria, increases urinary osmolality, and decreases free water clearance via upregulation of renal AQP2 and UT-A1.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESPFoundation for the Support of Research in the State of Sao Paulo)Foundation for the Support of Research in the State of Sao Paulo)Laboratorios de Investigacao Medica (LIMsLaboratorios de Investigacao Medica (LIMsMedical Investigation Laboratories) of the Faculdade de Medicina da Universidade de Sao Paulo (FMUSPMedical Investigation Laboratories) of the Faculdade de Medicina da Universidade de Sao Paulo (FMUSPUniversity of Sao Paulo School of Medicine) Hospital das ClinicasUniversity of Sao Paulo School of Medicine) Hospital das ClinicasConselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPqNational Council for Scientific and Technological DevelopmentNational Council for Scientific and Technological Development) [134318/2006-4, 309430/2006-7, 302835/2009-1

Lineage-Negative Bone Marrow Cells Protect Against Chronic Renal Failure

Progressive renal failure continues to be a challenge. the use of bone marrow cells represents a means of meeting that challenge. We used lineage-negative (Lin(-)) cells to test the hypothesis that Lin(-) cell treatment decreases renal injury. Syngeneic Fischer 344 rats were divided into four groups: sham ( laparotomy only, untreated); Nx (five-sixth nephrectomy and untreated); NxLC1 (five-sixth nephrectomy and receiving 2 x 10(6) Lin(-) cells on postnephrectomy day 15); and NxLC3 (five-sixth nephrectomy and receiving 2 x 10(6) Lin(-) cells on postnephrectomy days 15, 30, and 45). On postoperative day 16, renal mRNA expression of interleukin (IL)-1 beta, tumor necrosis factor-alpha, and IL-6 was lower in NxLC rats than in Nx rats. On postnephrectomy day 60, NxLC rats presented less proteinuria, glomerulosclerosis, anemia, renal infiltration of immune cells, and protein expression of monocyte chemoattractant protein-1, as well as decreased interstitial area. Immunostaining for proliferating cell nuclear antigen showed that, in comparison with sham rats, Nx rats presented greater cell proliferation, whereas NxLC1 rats and NxLC3 rats presented less cell proliferation than did Nx rats. Protein expression of the cyclin-dependent kinase inhibitor p21 and of vascular endothelial growth factor increased after nephrectomy and decreased after Lin(-) cell treatment. On postnephrectomy day 120, renal function (inulin clearance) was significantly better in Lin(-) cell-treated rats than in untreated rats. Lin(-) cell treatment significantly improved survival. These data suggest that Lin(-) cell treatment protects against chronic renal failure. STEM CELLS 2009; 27: 682-692Univ São Paulo, Sch Med, Fac Med,Lab Pesquisa Basica LIM 12, Dept Nephrol, BR-01246903 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Nephrol, São Paulo, BrazilUniv São Paulo, Dept Immunol, BR-01246903 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Nephrol, São Paulo, BrazilWeb of Scienc