NIELS OLSEN SARAIVA CAMARA
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BMI, ICB - Docente
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
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- 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.
- NF-kappa B System Is Chronically Activated and Promotes Glomerular Injury in Experimental Type 1 Diabetic Kidney Disease(2020) FORESTO-NETO, Orestes; ALBINO, Amanda Helen; ARIAS, Simone Costa Alarcon; FAUSTINO, Viviane Dias; ZAMBOM, Fernanda Florencia Fregnan; CENEDEZE, Marcos Antonio; ELIAS, Rosilene Motta; MALHEIROS, Denise Maria Avancini Costa; CAMARA, Niels Olsen Saraiva; FUJIHARA, Clarice Kazue; ZATZ, RobertoHigh glucose concentration can activate TLR4 and NF-kappa B, triggering the production of proinflammatory mediators. We investigated whether the NF-kappa B pathway is involved in the pathogenesis and progression of experimental diabetic kidney disease (DKD) in a model of long-term type 1 diabetes mellitus (DM). Adult male Munich-Wistar rats underwent DM by a single streptozotocin injection, and were kept moderately hyperglycemic by daily insulin injections. After 12 months, two subgroups - progressors and non-progressors - could be formed based on the degree of glomerulosclerosis. Only progressors exhibited renal TLR4, NF-kappa B and IL-6 activation. This scenario was already present in rats with short-term DM (2 months), at a time when no overt glomerulosclerosis can be detected. Chronic treatment with the NF-kappa B inhibitor, pyrrolidine dithiocarbamate (PDTC), prevented activation of renal TLR4, NF-kappa B or IL-6, without interfering with blood glucose. PDTC prevented the development of glomerular injury/inflammation and oxidative stress in DM rats. In addition, the NF-kappa B p65 component was detected in sclerotic glomeruli and inflamed interstitial areas in biopsy material from patients with type 1 DM. These observations indicate that the renal NF-kappa B pathway plays a key role in the development and progression of experimental DKD, and can become an important therapeutic target in the quest to prevent the progression of human DKD.
- Inflammation in Renal Diseases: New and Old Players(2019) ANDRADE-OLIVEIRA, Vinicius; FORESTO-NETO, Orestes; WATANABE, Ingrid Kazue Mizuno; ZATZ, Roberto; CAMARA, Niels Olsen SaraivaInflammation, a process intimately linked to renal disease, can be defined as a complex network of interactions between renal parenchymal cells and resident immune cells, such as macrophages and dendritic cells, coupled with recruitment of circulating monocytes, lymphocytes, and neutrophils. Once stimulated, these cells activate specialized structures such as Toll-like receptor and Nod-like receptor (NLR). By detecting danger-associated molecules, these receptors can set in motion major innate immunity pathways such as nuclear factor kappa B (NF-kappa B) and NLRP3 inflammasome, causing metabolic reprogramming and phenotype changes of immune and parenchymal cells and triggering the secretion of a number of inflammatory mediators that can cause irreversible tissue damage and functional loss. Growing evidence suggests that this response can be deeply impacted by the crosstalk between the kidneys and other organs, such as the gut. Changes in the composition and/or metabolite production of the gut microbiota can influence inflammation, oxidative stress, and fibrosis, thus offering opportunities to positively manipulate the composition and/or functionality of gut microbiota and, consequentially, ameliorate deleterious consequences of renal diseases. In this review, we summarize the most recent evidence that renal inflammation can be ameliorated by interfering with the gut microbiota through the administration of probiotics, prebiotics, and postbiotics. In addition to these innovative approaches, we address the recent discovery of new targets for drugs long in use in clinical practice. Angiotensin II receptor antagonists, NF-kappa B inhibitors, thiazide diuretics, and antimetabolic drugs can reduce renal macrophage infiltration and slow down the progression of renal disease by mechanisms independent of those usually attributed to these compounds. Allopurinol, an inhibitor of uric acid production, has been shown to decrease renal inflammation by limiting activation of the NLRP3 inflammasome. So far, these protective effects have been shown in experimental studies only. Clinical studies will establish whether these novel strategies can be incorporated into the arsenal of treatments intended to prevent the progression of human disease.
- Understanding the Metabolic Profile of Macrophages During the Regenerative Process in Zebrafish(2019) PAREDES, Lais Cavalieri; CAMARA, Niels Olsen Saraiva; BRAGA, Tarcio TeodoroIn contrast to mammals, lower vertebrates, including zebrafish (Danio rerio), have the ability to regenerate damaged or lost tissues, such as the caudal fin, which makes them an ideal model for tissue and organ regeneration studies. Since several diseases involve the process of transition between fibrosis and tissue regeneration, it is necessary to attain a better understanding of these processes. It is known that the cells of the immune system, especially macrophages, play essential roles in regeneration by participating in the removal of cellular debris, release of pro- and anti-inflammatory factors, remodeling of components of the extracellular matrix and alteration of oxidative patterns during proliferation and angiogenesis. Immune cells undergo phenotypical and functional alterations throughout the healing process due to growth factors and cytokines that are produced in the tissue microenvironment. However, some aspects of the molecular mechanisms through which macrophages orchestrate the formation and regeneration of the blastema remain unclear. In the present review, we outline how macrophages orchestrate the regenerative process in zebrafish and give special attention to the redox balance in the context of tail regeneration.
- Renal Inflammation and Innate Immune Activation Underlie the Transition From Gentamicin-Induced Acute Kidney Injury to Renal Fibrosis(2021) ALBINO, Amanda Helen; ZAMBOM, Fernanda Florencia Fregnan; FORESTO-NETO, Orestes; OLIVEIRA, Karin Carneiro; AVILA, Victor Ferreira; ARIAS, Simone Costa Alarcon; SEGURO, Antonio Carlos; MALHEIROS, Denise Maria Avancini Costa; CAMARA, Niels Olsen Saraiva; FUJIHARA, Clarice Kazue; ZATZ, RobertoSubjects recovering from acute kidney injury (AKI) are at risk of developing chronic kidney disease (CKD). The mechanisms underlying this transition are unclear and may involve sustained activation of renal innate immunity, with resulting renal inflammation and fibrosis. We investigated whether the NF-kappa B system and/or the NLRP3 inflammasome pathway remain activated after the resolution of AKI induced by gentamicin (GT) treatment, thus favoring the development of CKD. Male Munich-Wistar rats received daily subcutaneous injections of GT, 80 mg/kg, for 9 days. Control rats received vehicle only (NC). Rats were studied at 1, 30, and 180 days after GT treatment was ceased. On Day 1, glomerular ischemia (ISCH), tubular necrosis, albuminuria, creatinine retention, and tubular dysfunction were noted, in association with prominent renal infiltration by macrophages and myofibroblasts, along with increased renal abundance of TLR4, IL-6, and IL1 beta. Regression of functional and structural changes occurred on Day 30. However, the renal content of IL-1 beta was still elevated at this time, while the local renin-angiotensin system remained activated, and interstitial fibrosis became evident. On Day 180, recurring albuminuria and mild glomerulosclerosis were seen, along with ISCH and unabated interstitial fibrosis, whereas macrophage infiltration was still evident. GT-induced AKI activates innate immunity and promotes renal inflammation. Persistence of these abnormalities provides a plausible explanation for the transition of AKI to CKD observed in a growing number of patients.