ROBERTO ZATZ
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Clínica Médica, Faculdade de Medicina - Docente
LIM/16 - Laboratório de Fisiopatologia Renal, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/16 - Laboratório de Fisiopatologia Renal, Hospital das Clínicas, Faculdade de Medicina - Líder
59 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 59
bookPart Rins e envelhecimento(2015) LO, Simone Chinwa; SEGURO, Antonio Carlos; ZATZ, Roberto- Fluid Redistribution in Sleep Apnea: Therapeutic Implications in Edematous States(2018) SILVA, Bruno Caldin da; KASAI, Takatoshi; COELHO, Fernando Morgadinho; ZATZ, Roberto; ELIAS, Rosilene M.Sleep apnea (SA), a condition associated with increased cardiovascular risk, has been traditionally associated with obesity and aging. However, in patients with fluid-retaining states, such as congestive heart failure and end-stage renal disease, both prevalence and severity of SA are increased. Recently, fluid shift has been recognized to play an important role in the pathophysiology of SA, since the fluid retained in the legs during the day shifts rostrally while recumbent, leading to edema of upper airways. Such simple physics, observed even in healthy individuals, has great impact in patients with fluid overload. Correction of the excess fluid volume has risen as a potential target therapy to improve SA, by attenuation of nocturnal fluid shift. Such strategy has gained special attention, since the standard treatment for SA, the positive airway pressure, has low compliance rates among its users and has failed to reduce cardiovascular outcomes. This review focuses on the pathophysiology of edema and fluid shift, and summarizes the most relevant findings of studies that investigated the impact of treating volume overload on SA. We aim to expand horizons in the treatment of SA by calling attention to a potentially reversible condition, which is commonly underestimated in clinical practice.
- Pivotal Role of Toll-Like Receptors 2 and 4, Its Adaptor Molecule MyD88, and Inflammasome Complex in Experimental Tubule-Interstitial Nephritis(2011) CORREA-COSTA, Matheus; BRAGA, Tarcio Teodoro; SEMEDO, Patricia; HAYASHIDA, Caroline Yuri; BECHARA, Luiz Roberto Grassmann; ELIAS, Rosa Maria; BARRETO, Claudiene Rodrigues; SILVA-CUNHA, Claudia; HYANE, Meire Ioshie; GONCALVES, Giselle Martins; BRUM, Patricia Chakur; FUJIHARA, Clarice; ZATZ, Roberto; PACHECO-SILVA, Alvaro; ZAMBONI, Dario S.; CAMARA, Niels Olsen SaraivaTubule-interstitial nephritis (TIN) results in decreased renal function and interstitial inflammation, which ultimately leads to fibrosis. Excessive adenine intake can cause TIN because xanthine dehydrogenase (XDH) can convert this purine into an insoluble compound, which precipitates in the tubuli. Innate immune sensors, such as Toll-like receptors (TLR) and inflammasome complex, play a crucial role in the initiation of inflammation. The aim of this study was to evaluate the roles of TLR-2 and -4, Myd88 and inflammasome complex in an experimental model of TIN. Here, we show that wild-type (WT) mice fed adenine-enriched food exhibited significant renal dysfunction and enhanced cellular infiltration accompanied by collagen deposition. They also presented higher gene and protein expression of pro-inflammatory cytokines. In contrast, TLR-2, -4, MyD88, ASC and Caspase-1 KO mice showed renoprotection associated with expression of inflammatory molecules at levels comparable to controls. Furthermore, treatment of WT animals with allopurinol, an XDH inhibitor, led to reduced levels of uric acid, oxidative stress, collagen deposition and a downregulation of the NF-kB signaling pathway. We concluded that MyD88 signaling and inflammasome participate in the development of TIN. Furthermore, inhibition of XDH seems to be a promising way to therapeutically target the developing inflammatory process.
- NLRP3 inflammasome inhibition ameliorates tubulointerstitial injury in the remnant kidney model(2018) FORESTO-NETO, Orestes; AVILA, Victor Ferreira; ARIAS, Simone Costa Alarcon; ZAMBOM, Fernanda Florencia Fregnan; REMPEL, Lisienny Campoli Tono; FAUSTINO, Viviane Dias; MACHADO, Flavia Gomes; MALHEIROS, Denise Maria Avancini Costa; ABENSUR, Hugo; CAMARA, Niels Olsen Saraiva; ZATZ, Roberto; FUJIHARA, Clarice KazueRecent studies suggest that NLRP3 inflammasome activation is involved in the pathogenesis of chronic kidney disease (CKD). Allopurinol (ALLO) inhibits xanthine oxidase (XOD) activity, and, consequently, reduces the production of uric acid (UA) and reactive oxygen species (ROS), both of which can activate the NLRP3 pathway. Thus, ALLO can contribute to slow the progression of CKD. We investigated whether inhibition of XOD by ALLO reduces NLRP3 activation and renal injury in the 5/6 renal ablation (Nx) model. Adult male Munich-Wistar rats underwent Nx and were subdivided into the following two groups: Nx, receiving vehicle only, and Nx + ALLO, Nx rats given ALLO, 36 mg/Kg/day in drinking water. Rats undergoing sham operation were studied as controls (C). Sixty days after surgery, Nx rats exhibited marked albuminuria, creatinine retention, and hypertension, as well as glomerulosclerosis, tubular injury, and cortical interstitial expansion/inflammation/fibrosis. Such changes were accompanied by increased XOD activity and UA renal levels, associated with augmented heme oxigenase-1 and reduced superoxide dismutase-2 renal contents. Both the NF-kappa B and NLRP3 signaling pathways were activated in Nx. ALLO normalized both XOD activity and the parameters of oxidative stress. ALLO also attenuated hypertension and promoted selective tubulointerstitial protection, reducing urinary NGAL and cortical interstitial injury/inflammation. ALLO reduced renal NLRP3 activation, without interfering with the NF-kappa B pathway. These observations indicate that the tubulointerstitial antiinflammatory and antifibrotic effects of ALLO in the Nx model involve inhibition of the NLRP3 pathway, and reinforce the view that ALLO can contribute to arrest or slow the progression of CKD.
- Furosemide Increases the Risk of Hyperparathyroidism in Chronic Kidney Disease(2016) VASCO, Raquel F. V.; MOYSES, Rosa M. A.; ZATZ, Roberto; ELIAS, Rosilene M.Background: Diuretics are widely used in patients with chronic kidney disease (CKD). While thiazide-like diuretics limit urinary calcium excretion, loop diuretics (LD) promote calcium wasting, which might facilitate the development of secondary hyperparathyroidism (HPT2). We sought to investigate, in CKD patients not on dialysis, the influence of either hydrochlorothiazide (Hydro) or furosemide (Furo) on circulating parathyroid hormone (PTH) and whether such actions are determined by the effects of these compounds on calcium excretion. Methods: Electronic charts of all nephrology outpatients (CKD stages 2-5) who were given Hydro or Furo were included. We assessed estimated glomerular filtration rate (eGFR), biochemical parameters and 24-hour calcium excretion. Hyperparathyroidism was defined as PTH > 65 pg/ml. Results: Out of 275 patients, 108 (29%) were taking Hydro and 167 (61%) Furo. Patients on Hydro were younger, mostly female and had higher eGFR. The median 24-hour urinary calcium excretion in the overall cohort was 41 (22, 76), being lower in Furo than in Hydro patients (37 (16, 68) vs. 47 (26, 88) mg/24 h, respectively, p = 0.016). Logistic regression showed that, after adjustment for eGFR, calcium excretion rate was found not to increase the risk ratio for HPT2, where as Furo was a strong predictor of HPT2. Conclusion: Furo increased the risk of HPT2 among CKD patients compared to Hydro. This effect was independent of eGFR or calcium excretion. The use of LD in CKD, currently preferred in advanced stages, should be reappraised. (C) 2016 S. Karger AG, Basel
- Pathogenic role of innate immunity in a model of chronic NO inhibition associated with salt overload(2019) ZAMBOM, Fernanda Florencia Fregnan; OLIVEIRA, Karin Carneiro; FORESTO-NETO, Orestes; FAUSTINO, Viviane Dias; AVILA, Victor Ferreira; ALBINO, Amanda Helen; ARIAS, Simone Costa Alarcon; VOLPINI, Rildo Aparecido; MALHEIROS, Denise Maria Avancini Costa; CAMARA, Niels Olsen Saraiva; ZATZ, Roberto; FUJIHARA, Clarke KazueNitric oxide inhibition with N-omega-nitro-L-arginine methyl ester (L-NAME), along with salt overload, leads to hypertension, albuminuria, glomerulosclerosis, glomerular ischemia, and interstitial fibrosis, characterizing a chronic kidney disease (CKD) model. Previous findings of this laboratory and elsewhere have suggested that activation of at least two pathways of innate immunity, Toll-like receptor 4 (TLR4)/NF-kappa B and nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain containing 3 (NLRP3) inflammasome/IL-1 beta, occurs in several experimental models of CKD and that progression of renal injury can be slowed with inhibition of these pathways. In the present study, we investigated whether activation of innate immunity, through either the TLR4/NF-kappa B or NLRP3/IL-1 beta pathway, is involved in the pathogenesis of renal injury in chronic nitric oxide inhibition with the salt-overload model. Adult male Munich-Wistar rats that received L-NAME in drinking water with salt overload (HS + N group) were treated with allopurinol (ALLO) as an NLRP3 inhibitor (HS + N + ALLO group) or pyrrolidine dithiocarbamate (PDTC) as an NF-kappa B inhibitor (HS + N + PDTC group). After 4 wk, HS + N rats developed hypertension, albuminuria, and renal injury along with renal inflammation, oxidative stress, and activation of both the NLRP3/IL-1 beta and TLR4/NF-kappa B pathways. ALLO lowered renal uric acid and inhibited the NLRP3 pathway. These effects were associated with amelioration of hypertension, albuminuria, and interstitial inflammation/fibrosis but not glomerular injury. PDTC inhibited the renal NF-kappa B system and lowered the number of interstitial cells staining positively for NLRP3. PDTC also reduced renal xanthine oxidase activity and uric acid. Overall, PDTC promoted a more efficient anti-inflammatory and nephroprotective effect than ALLO. The NLRP3/IL-1 beta and TLR4/NF-kappa B pathways act in parallel to promote renal injury/inflammation and must be simultaneously inhibited for best nephroprotection.
bookPart Doença renal diabética(2022) LIRA, Aécio Lopes de Araújo; BATTAINI, Ligia Costa; QUEIROZ, Márcia Silva; ZATZ, Roberto- Effects of losartan, in monotherapy or in association with hydrochlorothiazide, in chronic nephropathy resulting from losartan treatment during lactation(2011) FANELLI, C.; FERNANDES, B. H. V.; MACHADO, F. G.; OKABE, C.; MALHEIROS, D. M. A. C.; FUJIHARA, C. K.; ZATZ, R.Fanelli C, Fernandes BH, Machado FG, Okabe C, Malheiros DM, Fujihara CK, Zatz R. Effects of losartan, in monotherapy or in association with hydrochlorothiazide, in chronic nephropathy resulting from losartan treatment during lactation. Am J Physiol Renal Physiol 301: F580-F587, 2011. First published June 8, 2011; doi:10.1152/ajprenal.00042.2011.-We recently standardized a model (L(Lact)) of severe chronic kidney disease based on impaired nephrogenesis by suppression of angiotensin II activity during lactation (Machado FG, Poppi EP, Fanelli C, Malheiros DM, Zatz R, Fujihara CK. Am J Physiol Renal Physiol 294: F1345-F1353, 2008). In this new study of the L(Lact) model, we sought to gain further insight into renal injury mechanisms associated with this model and to verify whether the renoprotection obtained with the association of the angiotensin II receptor blocker losartan (L) and hydrochlorothiazide (H), which arrested renal injury in the remnant kidney model, would provide similar renoprotection. Twenty Munich-Wistar dams, each nursing six pups, were divided into control, untreated, and L(Lact) groups, given losartan (L; 250 mg.kg(-1).day(-1)) until weaning. The male LLact offspring remained untreated until 7 mo of age, when renal functional and structural parameters were studied in 17 of them, used as pretreatment control (L(Lact)Pre), and followed no further. The remaining rats were then divided among groups L(Lact) + V, untreated; L(Lact) + L, given L (50 mg.kg(-1).day(-1)) now as a therapy; L(Lact) + H, given H (6 mg.kg(-1).day(-1)); and L(Lact) + LH, given L and H. All parameters were reassessed 3 mo later in these groups and in age-matched controls. At this time, L(Lact) rats exhibited hypertension, severe albuminuria, glomerular damage, marked interstitial expansion/inflammation, enhanced cell proliferation, myofibroblast infiltration, and creatinine retention. L monotherapy normalized albuminuria and prevented hypertension and the progression of renal injury, inflammation, and myofibroblast infiltration. In contrast to the remnant model, the LH combination promoted only slight additional renoprotection, perhaps because of a limited tendency to retain sodium in L(Lact) rats.
bookPart Intoxicação hídrica(2022) ZATZ, Roberto; SEGURO, Antonio Carlos- Chronic environmental hypoxia attenuates innate immunity activation and renal injury in two CKD models(2023) ZAMBOM, Fernanda Florencia Fregnan; ALBINO, Amanda Helen; TESSARO, Helena Mendonca; FORESTO-NETO, Orestes; MALHEIROS, Denise Maria Avancini Costa; CAMARA, Niels Olsen Saraiva; ZATZ, RobertoTissue hypoxia has been pointed out as a major pathogenic factor in chronic kidney disease (CKD). However, epidemiological and experimental evidence inconsistent with this notion has been described. We have previously reported that chronic exposure to low ambient Po-2 promoted no renal injury in normal rats and in rats with 5/6 renal ablation (Nx) unexpectedly attenuated renal injury. In the present study, we investigated whether chronic exposure to low ambient Po-2 would also be renoprotective in two additional models of CKD: adenine (ADE) excess and chronic nitric oxide (NO) inhibition. In both models, normobaric ambient hypoxia attenuated the development of renal injury and inflammation. In addition, renal hypoxia limited the activation of NF-?B and NOD-like receptor family pyrin domain containing 3 inflammasome cascades as well as oxidative stress and intrarenal infiltration by angiotensin II-positive cells. Renal activation of hypoxia-inducible factor (HIF)-2a, along with other adaptive mechanisms to hypoxia, may have contributed to these renoprotective effects. The present findings may contribute to unravel the pathogenesis of CKD and to the development of innovative strategies to arrest its progression.