SIMONE DA COSTA ALARCON ARIAS
Projetos de Pesquisa
Unidades Organizacionais
LIM/16 - Laboratório de Fisiopatologia Renal, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- 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.
- An association of losartan-hydrochlorothiazide, but not losartan-furosemide, completely arrests progressive injury in the remnant kidney(2016) ARIAS, Simone Costa Alarcon; SOUZA, Renata Alves; MALHEIROS, Denise Maria Avancini Costa; FANELLI, Camilla; FUJIHARA, Clarice Kazue; ZATZ, RobertoWe have previously shown that an association of losartan and hydrochlorothiazide, initiated 1 mo after 5/6 nephrectomy (Nx), reversed hypertension and albuminuria and promoted lasting renoprotection. In this new study, we investigated whether equal or even better protection could be obtained by combining losartan and furosemide. Nx was performed in 58 Munich-Wistar rats. One month later, tail-cuff pressure and albuminuria were markedly elevated. At this time, Nx rats were distributed among the following four groups: untreated Nx rats, Nx rats that received losartan, Nx rats that received losartan + hydrochlorothiazide, and Nx rats that received losartan + furosemide. Seven months later, Nx rats exhibited high mortality, severe hypertension, albuminuria, glomerulosclerosis, and interstitial fibrosis. Losartan treatment limited mortality and attenuated the renal and hemodynamic abnormalities associated with Nx. As previously shown, the losartan + hydrochlorothiazide association normalized tail-cuff pressure and albumin, prevented renal injury, and reduced mortality to zero. The losartan + furosemide treatment failed to reduce tail-cuff pressure or albumin to normal and prevented renal injury less efficiently than the losartan and hydrochlorothiazide regimen. The reasons for the differing efficacies of the losartan + furosemide and losartan + hydrochlorothiazide schemes are unclear and may include beneficial nondiuretic actions of thiazides, such as vasorelaxation and antiproliferative activity. These results refute the established concept that thiazides and thiazide-like diuretics are ineffective at advanced chronic kidney disease stages. Rather, they suggest that, in view of their renoprotective action, these compounds may even be preferable to loop diuretics in the management of hypertension in advanced chronic kidney disease.
- Chronic exposure to hypoxia attenuates renal injury and innate immunity activation in the remnant kidney model(2019) REMPEL, Lisienny Campoli Tono; FAUSTINO, Viviane Dias; FORESTO-NETO, Orestes; FANELLI, Camilla; ARIAS, Simone Costa Alarcon; MOREIRA, Gizely Cristina da Silva; NASCIMENTO, Thalita Fabiana; AVILA, Victor Ferreira; MALHEIROS, Denise Maria Avancini Costa; CAMARA, Niels Olsen Saraiva; FUJIHARA, Clarice Kazue; ZATZ, RobertoHypoxia is thought to influence the pathogenesis of chronic kidney disease, but direct evidence that prolonged exposure to tissue hypoxia initiates or aggravates chronic kidney disease is lacking. We tested this hypothesis by chronically exposing normal rats and rats with 5/6 nephrectomy (Nx) to hypoxia. In addition, we investigated whether such effect of hypoxia would involve activation of innate immunity. Adult male Munich-Wistar rats underwent Nx (n = 54) or sham surgery (sham; n = 52). Twenty-six sham rats and 26 Nx rats remained in normoxia, whereas 26 sham rats and 28 Nx rats were kept in a normobaric hypoxia chamber (12% O-2) for 8 wk. Hypoxia was confirmed by immunohistochemistry for pimonidazole. Hypoxia was confined to the medullary area in sham + normoxia rats and spread to the cortical area in sham + hypoxia rats, without changing the peritubular capillary density. Exposure to hypoxia promoted no renal injury or elevation of the content of IL-1 beta or Toll-like receptor 4 in sham rats. In Nx, hypoxia also extended to the cortical area without ameliorating the peritubular capillary rarefaction but, unexpectedly, attenuated hypertension, inflammation, innate immunity activation, renal injury, and oxidative stress. The present study, in disagreement with current concepts. shows evidence that hypoxia exerts a renoprotective effect in the Nx model instead of acting as a factor of renal injury. The mechanisms for this unexpected beneficial effect are unclear and may involve NF-kappa B inhibition, amelioration of oxidative stress, and limitation of angiotensin II production by the renal tissue.
- NF-kappa B activation mediates crystal translocation and interstitial inflammation in adenine overload nephropathy(2013) OKABE, Cristiene; BORGES, Raquel Lerner; ALMEIDA, Danilo Candido de; FANELLI, Camilla; BARLETTE, Grasiela Pedreira; MACHADO, Flavia Gomes; ARIAS, Simone Costa Alarcon; MALHEIROS, Denise Maria Avancini Costa; CAMARA, Niels Olsen Saraiva; ZATZ, Roberto; FUJIHARA, Clarice KazueAdenine overload promotes intratubular crystal precipitation and interstitial nephritis. We showed recently that these abnormalities are strongly attenuated in mice knockout for Toll-like receptors-2, -4, MyD88, ASC, or caspase-1. We now investigated whether NF-kappa B activation also plays a pathogenic role in this model. Adult male Munich-Wistar rats were distributed among three groups: C (n = 17), receiving standard chow; ADE (n = 17), given adenine in the chow at 0.7% for 1 wk and 0.5% for 2 wk; and ADE + pyrrolidine dithiocarbamate (PDTC; n = 14), receiving adenine as above and the NF-kappa B inhibitor PDTC (120 mg.kg(-1).day(-1) in the drinking water). After 3 wk, widespread crystal deposition was seen in tubular lumina and in the renal interstitium, along with granuloma formation, collagen accumulation, intense tubulointerstitial proliferation, and increased interstitial expression of inflammatory mediators. Part of the crystals were segregated from tubular lumina by a newly formed cell layer and, at more advanced stages, appeared to be extruded to the interstitium. p65 nuclear translocation and IKK-alpha increased abundance indicated activation of the NF-kappa B system. PDTC treatment prevented p65 migration and normalized IKK-alpha, limited crystal shift to the interstitium, and strongly attenuated interstitial fibrosis/inflammation. These findings indicate that the complex inflammatory phenomena associated with this model depend, at least in part, on NF-kappa B activation, and suggest that the NF-kappa B system may become a therapeutic target in the treatment of chronic kidney disease.
- NF-kappa B blockade during short-term L-NAME and salt overload strongly attenuates the late development of chronic kidney disease(2020) OLIVEIRA, Karin Carneiro; ZAMBOM, Fernanda Florencia Fregnan; ALBINO, Amanda Helen; ARIAS, Simone Costa Alarcon; AVILA, Victor Ferreira; FAUSTINO, Viviane Dias; MALHEIROS, Denise Maria Avancini Costa; CAMARA, Niels Olsen Saraiva; FUJIHARA, Clarice Kazue; ZATZ, RobertoNitric oxide synthase inhibition by N-omega-nitro-L-arginine methyl ester (L-NAME) plus a high-salt diet (HS) is a model of chronic kidney disease (CKD) characterized by marked hypertension and renal injury. With cessation of treatment, most of these changes subside, but progressive renal injury develops, associated with persistent low-grade renal inflammation. We investigated whether innate immunity. and in particular the NF-kappa B system, is involved in this process. Male Munich-Wistar rats received HS + L-NAME (32 mg.kg(-1).day(-1)), whereas control rats received HS only. Treatment was ceased after week 4 when 30 rats were studied. Additional rats were studied at week 8 (n = 30) and week 28 (n = 30). As expected, HS + L-NAME promoted severe hypertension, albuminuria, and renal injury after 4 wk of treatment, whereas innate immunity activation was evident. After discontinuation of treatments, partial regression of renal injury and inflammation occurred, along with persistence of innate immunity activation at week 8. At week 28, glomerular injury worsened, while renal inflammation persisted and renal innate immunity remained activated. Temporary administration of the NF-kappa B inhibitor pyrrolidine dithiocarbamate, in concomitancy with the early 4-wk HS + L-NAME treatment, prevented the development of late renal injury and inflammation, an effect that lasted until the end of the study. Early activation of innate immunity may be crucial to the initiation of renal injury in the HS + L-NAME model and to the autonomous progression of chronic nephropathy even after cessation of the original insult. This behavior may be common to other conditions leading to CKD.