ANTONIO CARLOS SEGURO
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/12 - Laboratório de Pesquisa Básica em Doenças Renais, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/12 - Laboratório de Pesquisa Básica em Doenças Renais, Hospital das Clínicas, Faculdade de Medicina - Líder
17 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 17
- Vitamin D Deficiency Aggravates Chronic Kidney Disease Progression after Ischemic Acute Kidney Injury(2014) GONCALVES, Janaina Garcia; BRAGANCA, Ana Carolina de; CANALE, Daniele; SHIMIZU, Maria Heloisa Massola; SANCHES, Talita Rojas; MOYSES, Rosa Maria Affonso; ANDRADE, Lucia; SEGURO, Antonio Carlos; VOLPINI, Rildo AparecidoBackground: Despite a significant improvement in the management of chronic kidney disease (CKD), its incidence and prevalence has been increasing over the years. Progressive renal fibrosis is present in CKD and involves the participation of several cytokines, including Transforming growth factor-beta 1 (TGF-beta 1). Besides cardiovascular diseases and infections, several studies show that Vitamin D status has been considered as a non-traditional risk factor for the progression of CKD. Given the importance of vitamin D in the maintenance of essential physiological functions, we studied the events involved in the chronic kidney disease progression in rats submitted to ischemia/reperfusion injury under vitamin D deficiency (VDD). Methods: Rats were randomized into four groups: Control; VDD; ischemia/reperfusion injury (IRI); and VDD+IRI. At the 62 day after sham or IRI surgery, we measured inulin clearance, biochemical variables and hemodynamic parameters. In kidney tissue, we performed immunoblotting to quantify expression of Klotho, TGF-beta, and vitamin D receptor (VDR); gene expression to evaluate renin, angiotensinogen, and angiotensin-converting enzyme; and immunohistochemical staining for ED1 (macrophages), type IV collagen, fibronectin, vimentin, and alpha-smooth mucle actin. Histomorphometric studies were performed to evaluate fractional interstitial area. Results: IRI animals presented renal hypertrophy, increased levels of mean blood pressure and plasma PTH. Furthermore, expansion of the interstitial area, increased infiltration of ED1 cells, increased expression of collagen IV, fibronectin, vimentin and alpha-actin, and reduced expression of Klotho protein were observed. VDD deficiency contributed to increased levels of plasma PTH as well as for important chronic tubulointerstitial changes (fibrosis, inflammatory infiltration, tubular dilation and atrophy), increased expression of TGF-beta 1 and decreased expression of VDR and Klotho protein observed in VDD+IRI animals. Conclusion: Through inflammatory pathways and involvement of TGF-beta 1 growth factor, VDD could be considered as an aggravating factor for tubulointerstitial damage and fibrosis progression following acute kidney injury induced by ischemia/reperfusion.
- Vitamin D deficiency aggravates ischemic acute kidney injury in rats(2015) BRAGANCA, Ana Carolina de; VOLPINI, Rildo A.; CANALE, Daniele; GONCALVES, Janaina G.; SHIMIZU, Maria Heloisa M.; SANCHES, Talita R.; SEGURO, Antonio C.; ANDRADE, LuciaVitamin D deficiency (VDD) increases the risk of death in hospitalized patients. Renal ischemia/reperfusion injury (IRI) induces acute kidney injury (AKI), which activates cell cycle inhibitors, including p21, a cyclindependent kinase inhibitor and genomic target of 25-hydroxyvitamin D, which is in turn a potent immunomodulator with antiproliferative effects. In this study, we assess the impact of VDD in renal IRI. Wistar rats were divided into groups, each evaluated for 30 days: control (receiving a standard diet); VDD (receiving a vitamin D-free diet); IRI (receiving a standard diet and subjected to 45-min bilateral renal ischemia on day 28); and VDD + IRI (receiving a vitamin D-free diet and subjected to 45-min bilateral renal ischemia on day 28). At 48 h after IRI, animals were euthanized; blood, urine, and kidney tissue samples were collected. Compared with IRI rats, VDD + IRI rats showed a more severe decrease in glomerular filtration rate, greater urinary protein excretion, a higher kidney/body weight ratio and lower renal aquaporin 2 expression, as well as greater morphological damage, characterized by increased interstitial area and tubular necrosis. Our results suggest that the severity of tubular damage in IRI may be associated with downregulation of vitamin D receptors and p21. VDD increases renal inflammation, cell proliferation and cell injury in ischemic AKI.
- Apolipoprotein A-I mimetic peptide 4F attenuates kidney injury, heart injury, and endothelial dysfunction in sepsis(2014) MOREIRA, Roberto S.; IRIGOYEN, Maria; SANCHES, Talita R.; VOLPINI, Rildo A.; CAMARA, Niels O. S.; MALHEIROS, Denise M.; SHIMIZU, Maria H. M.; SEGURO, Antonio C.; ANDRADE, LuciaKidney injury, heart injury, and cytokine-induced vascular hyperpermeability are associated with high rates of morbidity and mortality in sepsis. Although the mechanism remains unknown, apolipoprotein A-I (apoA-I) mimetic peptide 4F reduces inflammation and protects HDL levels, which are reduced in sepsis. We hypothesized that 4F also protects kidneys and hearts in a rat model of cecal ligation and puncture (CLP). We divided Wistar rats into groups: sham-operated (control), CLP, and CLP+4F (10 mg/kg body wt ip, 6 h after CLP). At 24 h post-CLP, we evaluated cardiac function, mean arterial pressure (MAP), heart rate (HR), baroreflex sensitivity, total cholesterol, LDL, HDL, serum cytokines, and inulin clearance. We performed immunoblotting for protein regulators of vascular permeability (Slit2 and Robo4) and endothelial nitric oxide synthase (eNOS) in kidney tissue. We evaluated heart mitochondria with electron microscopy. Although there was no difference in MAP, the HR was significantly higher in CLP rats than in control and CLP+4F rats. In CLP+4F rats, baroreflex sensitivity and cardiac function were completely protected from the effects of CLP, as was glomerular filtration; heart mitochondria morphology was improved; sepsis-induced changes in serum cholesterol, LDL, HDL, and apoA-I were less common; all cytokines were lower than in CLP rats; and expression of Slit2, Robo4, and eNOS was completely restored. Administration of 4F inhibits inflammatory responses and strengthens the vascular barrier, protecting kidneys and hearts in an HDL-dependent manner. To determine the extent of the protective effect of 4F, further studies are needed.
- Renal Tubular Dysfunction in Sickle Cell Disease(2013) SILVA JUNIOR, Geraldo B.; VIEIRA, Ana Patricia F.; BEM, Amanda X. Couto; ALVES, Marilia P.; MENESES, Gdayllon C.; MARTINS, Alice M. C.; SANCHES, Talita R.; ANDRADE, Lucia C.; SEGURO, Antonio C.; LIBORIO, Alexandre B.; DAHER, Elizabeth F.Background/Aims: Kidney abnormalities are one of the main chronic complications of sickle cell disease (SCD). The aim of this study is to investigate the occurrence of renal tubular abnormalities among patients with SCD. Methods: This is a prospective study with 26 SCD adult patients in Brazil. Urinary acidification and concentration tests were performed using calcium chloride (CaCl2), after a 12h period of water and food deprivation. Fractional excretion of sodium (FENa), transtubular potassium gradient (TTKG) and solute free water reabsorption (TcH2O) were calculated. The SCD group was compared to a group of 15 healthy volunteers (control group). Results: Patient`s average age and gender were similar to controls. Urinary acidification deficit was found in 10 SCD patients (38.4%), who presented urinary pH > 5.3 after CaCl2 test. Urinary osmolality was significantly lower in SCD patients (355 +/- 60 vs. 818 +/- 202mOsm/kg, p= 0.0001, after 12h period water deprivation). Urinary concentration deficit was found in all SCD patients (100%). FENa was higher among SCD patients (0.75 +/- 0.3 vs. 0.55 +/- 0.2%, p= 0.02). The TTKG was higher in SCD patients (5.5 +/- 2.5 vs. 3.0 +/- 1.5, p= 0.001), and TcH2O was lower (0.22 +/- 0.3 vs. 1.1 +/- 0.3L/day, p= 0.0001). Conclusions: SCD is associated with important kidney dysfunction. The main abnormalities found were urinary concentrating and incomplete distal acidification defect. There was also an increase in the potassium transport and decrease in water reabsorption, evidencing the occurrence of distal tubular dysfunction.
conferenceObject TUBULOGLOMERULAR EVALUATION IN VISCERAL LEISHMANIASIS BEFORE AND AFTER TREATMENT WITH PENTAVALENT ANTIMONIAL(2014) OLIVEIRA, Michelle J. C.; SILVA JUNIOR, Geraldo; SAMPAIO, Aline M.; MONTENEGRO, Barbara; ALVES, Marilia P.; HENN, Guilherme A. L.; ROCHA, Hermano A. L.; MENESES, Gdayllon C.; MARTINS, Alice M. C.; SANCHES, Talita R.; ANDRADE, Lucia C.; SEGURO, Antonio C.; LIBORIO, Alexandre B.; DAHER, Elizabeth F.- Effects of Brazilian green propolis on proteinuria and renal function in patients with chronic kidney disease: a randomized, double-blind, placebo-controlled trial(2019) SILVEIRA, Marcelo Augusto Duarte; TELES, Flavio; BERRETTA, Andressa A.; SANCHES, Talita R.; RODRIGUES, Camila Eleuterio; SEGURO, Antonio Carlos; ANDRADE, LuciaBackgroundChronic kidney disease (CKD) is a public health problem worldwide, and proteinuria is a well-established marker of disease progression in CKD patients. Propolis, a natural resin produced by bees from plant materials, has anti-inflammatory, immunomodulatory, and anti-oxidant properties, as well as having been shown to have an antiproteinuric effect in experimental CKD. The aim of this study was to evaluate the impact of Brazilian green propolis extract on proteinuria reduction and the changes in the estimated glomerular filtration rate (eGFR).MethodsThis was a randomized, double-blind, placebo-controlled study including patients with CKD caused by diabetes or of another etiology, 18-90years of age, with an eGFR of 25-70ml/min per 1.73m(2) and proteinuria (urinary protein excretion >300mg/day) or micro- or macro-albuminuria (urinary albumin-to-creatinine ratio>30mg/g or>300mg/g, respectively). We screened 148 patients and selected 32, randomly assigning them to receive 12months of Brazilian green propolis extract at a dose of 500mg/day (n=18) or 12months of a placebo (n=14).ResultsAt the end of treatment, proteinuria was significantly lower in the propolis group than in the placebo group695mg/24h (95% CI, 483 to 999) vs. 1403mg/24h (95% CI, 1031 to 1909); P=0.004independent of variations in eGFR and blood pressure, which did not differ between the groups during follow-up. Urinary monocyte chemoattractant protein-1 was also significantly lower in the propolis group than in the placebo group58pg/mg creatinine (95% CI, 36 to 95) vs. 98pg/mg creatinine (95% CI, 62 to 155); P=0.038.ConclusionsBrazilian green propolis extract was found to be safe and well tolerated, as well as to reduce proteinuria significantly in patients with diabetic and non-diabetic CKD.Trial Registration.(ClinicalTrials.gov number NCT02766036. Registered: May 9, 2016).
- N-acetylcysteine attenuates renal alterations induced by senescence in the rat (vol 48, pg 298, 2013)(2013) SHIMIZU, M. H.; VOLPINI, R. A.; BRAGANCA, A. C. de; CAMPOS, R.; CANALE, D.; SANCHES, T. R.; ANDRADE, L.; SEGURO, A. C.
- Serum and Urinary Values of CA 19-9 and TGF beta 1 in a Rat Model of Partial or Complete Ureteral Obstruction(2015) LOPES, Roberto Iglesias; DENES, Francisco Tibor; BARTOLAMEI, Matheus Gesualdo; REIS, Sabrina; SANCHES, Talita Rojas; LEITE, Katia Ramos; SROUGI, Miguel; SEGURO, Antonio CarlosIntroduction Abnormal levels of serum and urinary markers occur in the presence of renal damage associated to obstructive uropathy. Urinary and serum transforming growth factor beta 1 (TGF beta 1) and carbohydrate antigen (CA 19-9) have not yet been evaluated in an experimental model of obstructive uropathy. Material and Methods Rats were divided into seven groups: reference, sham operation, unilateral nephrectomy, complete unilateral ureteral obstruction, partial unilateral ureteral obstruction, partial bilateral ureteral obstruction, and unilateral nephrectomy with contralateral partial ureteral obstruction. Kidney and ureter morphometry, TGF beta 1 and CA 19-9 serum and urinary concentrations and CA 19-9 renal tissue expression were analyzed. Correlation of these markers to complete, partial obstruction, or unobstructed groups was performed. Results Pathological findings correlated positively with the degree of ureteral obstruction, but negatively with urinary CA 19-9 levels. Marked underexpression of CA 19-9 was observed in kidneys with complete ureteral obstruction. No statistically significant differences were found for urinary and serum TGF beta 1 and also for serum CA 19-9. Conclusion Urinary CA 19-9 correlated negatively with ureteral obstruction grade. Immunohistochemistry depicted CA 19-9 expression on epithelial tubular cells cytoplasm, suggesting renal origin. Serum and urinary TGF beta 1 did not show alterations in response to severity and length of urinary obstruction, which might be associated with less intense renal remodeling.
- N-acetyl-cysteine is associated to renal function improvement in patients with nephropathic cystinosis(2014) GUIMARAES, Luciana Pache de Faria; SEGURO, Antonio Carlos; SHIMIZU, Maria Heloisa Mazzola; NERI, Leticia Aparecida Lopes; SUMITA, Nairo Massakasu; BRAGANCA, Ana Carolina de; VOLPINI, Rildo Aparecido; SANCHES, Talita Rojas Cunha; FONSECA, Fernanda Andrade Macaferri da; MOREIRA FILHO, Carlos Alberto; VAISBICH, Maria HelenaNephropathic cystinosis is an autosomal recessive systemic severe disease characterized by intralysosomal cystine storage. Cysteamine is an essential component of treatment. There is solid evidence that cystine accumulation itself is not responsible for all abnormalities in cystinosis; there is also a deficiency of glutathione in the cytosol. Patients with cystinosis can be more susceptible to oxidative stress. The patient cohort comprised 23 cystinosis patients (16 males) aged < 18 years (mean age 8.0 +/- 3.6 years) with chronic kidney disease class I-IV with good adherence to treatment, including cysteamine. Oxidative stress was evaluated based on the levels of serum thiobarbituric acid-reactive substances (TBARS), and renal function was evaluated based on serum creatinine and cystatin C levels and creatinine clearance (Schwartz formula). N-Acetylcysteine (NAC), an antioxidant drug was given to all patients for 3 months (T1) at 25 mg/kg/day divided in three doses per day. The measured values at just before the initiation of NAC treatment (T0) served as the control for each patient. Median serum TBARS levels at T0 and T1 were 6.92 (range 3.3-29.0) and 1.7 (0.6-7.2) nmol/mL, respectively (p < 0.0001). In terms of renal function at T0 and T1, serum creatinine levels (1.1 +/- 0.5 vs. 0.9 +/- 0.5 mg/dL, respectively; p < 0.0001), creatinine clearance (69.7 +/- 32.2 vs. T1 = 78.5 +/- 33.9 mL/min/1.73 m(2), respectively; p = 0.006), and cystatin c level (1.33 +/- 0.53 vs. 1.15 +/- 0.54 mg/l, respectively; p = 0.0057) were all significantly different at these two time points. Serum creatinine measurements at 6 (T -6) and 3 months (T -3) before NAC initiation and at 3 (T +3) and 6 months (T +6) after NAC had been withdrawn were also evaluated. During the 3-month period that our 23 cystinosis patients were treated with NAC, oxidative stress was reduced and renal function significantly improved. No side-effects were detected. Larger and controlled studies are needed to confirm these findings.
- Effects of Continuous Erythropoietin Receptor Activator in Sepsis-Induced Acute Kidney Injury and Multi-Organ Dysfunction(2012) RODRIGUES, Camila E.; SANCHES, Talita R.; VOLPINI, Rildo A.; SHIMIZU, Maria H. M.; KURIKI, Patricia S.; CAMARA, Niels O. S.; SEGURO, Antonio C.; ANDRADE, LuciaBackground: Despite advances in supportive care, sepsis-related mortality remains high, especially in patients with acute kidney injury (AKI). Erythropoietin can protect organs against ischemia and sepsis. This effect has been linked to activation of intracellular survival pathways, although the mechanism remains unclear. Continuous erythropoietin receptor activator (CERA) is an erythropoietin with a unique pharmacologic profile and long half-life. We hypothesized that pretreatment with CERA would be renoprotective in the cecal ligation and puncture (CLP) model of sepsis-induced AKI. Methods: Rats were randomized into three groups: control; CLP; and CLP+CERA (5 mu g/kg body weight, i.p. administered 24 h before CLP). At 24 hours after CLP, we measured creatinine clearance, biochemical variables, and hemodynamic parameters. In kidney tissue, we performed immunoblotting-to quantify expression of the Na-K-2Cl cotransporter (NKCC2), aquaporin 2 (AQP2), Toll-like receptor 4 (TLR4), erythropoietin receptor (EpoR), and nuclear factor kappa B (NF-kappa B)-and immunohistochemical staining for CD68 (macrophage infiltration). Plasma interleukin (IL)-2, IL-1 beta, IL-6, IL-10, interferon gamma, and tumor necrosis factor alpha were measured by multiplex detection. Results: Pretreatment with CERA preserved creatinine clearance and tubular function, as well as the expression of NKCC2 and AQP2. In addition, CERA maintained plasma lactate at normal levels, as well as preserving plasma levels of transaminases and lactate dehydrogenase. Renal expression of TLR4 and NF-kappa B was lower in CLP+CERA rats than in CLP rats (p<0.05 and p<0.01, respectively), as were CD68-positive cell counts (p<0.01), whereas renal EpoR expression was higher (p<0.05). Plasma levels of all measured cytokines were lower in CLP+CERA rats than in CLP rats. Conclusion: CERA protects against sepsis-induced AKI. This protective effect is, in part, attributable to suppression of the inflammatory response.