RICARDO COSTA PETRONI
Projetos de Pesquisa
Unidades Organizacionais
LIM/51 - Laboratório de Emergências Clínicas, Hospital das Clínicas, Faculdade de Medicina
5 resultados
Resultados de Busca
Agora exibindo 1 - 5 de 5
- High-fat diet inhibits PGC-1 alpha suppressive effect on NF kappa B signaling in hepatocytes(2018) BARROSO, Wermerson Assuncao; VICTORINO, Vanessa Jacob; JEREMIAS, Isabela Casagrande; PETRONI, Ricardo Costa; ARIGA, Suely Kunimi Kubo; SALLES, Thiago A.; BARBEIRO, Denise Frediani; LIMA, Thais Martins de; SOUZA, Heraldo Possolo deThe peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1 alpha) regulates the expression of genes implicated in fatty acid oxidation and oxidative phosphorylation. Its role in liver steatosis is well established, since mice with liver-specific deletion of PGC-1 alpha exhibit lipid accumulation and high-fat diet reduces hepatic PGC-1 alpha expression in mice. In this study, we investigated the role of PGC-1 alpha in the inflammatory changes observed in steatohepatitis induced by high-fat diet. C57black/6 mice were fed a high-fat diet containing 30% fat for 10 weeks. After euthanasia, liver morphology was examined by HE staining and inflammation was determined by IL-6, TNF-alpha, and IL-1 beta quantification. Liver gene expression of PGC-1 isoforms was evaluated by real-time PCR and p65 NF kappa B nuclear translocation by Western blotting. HepG2 cells were treated with linoleic acid overload for 72 h to create an in vitro model of steatohepatitis. RNA interference (RNAi) was used to evaluate the involvement of PGC-1 alpha on inflammatory mediators' production by hepatocytes. The high-fat diet led to a state of nonalcoholic steatohepatitis, associated with increased deposits of intra-abdominal fat, hyperglycemia and hyperlipidemia. Mice liver also exhibited increased proinflammatory cytokines' levels, decreased PGC-1 alpha expression, and marked increase in p65 NF kappa B nuclear translocation. Linoleic acid treated cells also presented increased expression of proinflammatory cytokines and decreased PGC-1 alpha expression. The knockdown of PGC-1 alpha content caused an increase in IL-6 expression and release via enhanced I kappa B alpha phosphorylation and subsequent increase of p65 NF kappa B nuclear translocation. High-fat diet induces liver inflammation by inhibiting PGC-1 alpha expression and its suppressive effect in NF kappa B pathway.
- Phagocytic activity of LPS tolerant macrophages(2014) LIMA, Thais Martins de; SAMPAIO, Sandra Coccuzzo; PETRONI, Ricardo; BRIGATTE, Patricia; VELASCO, Irineu Tadeu; SORIANO, Francisco GarciaEndotoxin tolerance is defined as a reduced capacity of the host to respond to LPS activation following a first exposure to this stimulus. It affects all leukocytes and regarding macrophages, most studies focus on the reduced ability of these cells to secrete pro-inflammatory cytokines. Therefore, we evaluated other macrophages functions (fungicidal capacity, reactive oxygen species production and antigen presentation) in cells from tolerant mice. We have performed a tolerance model in our laboratory that does not stimulate directly the place from where the cells will be removed (peritoneal cavity). Mouse received subcutaneous injections of LPS in the scruff for 5 days and we analyze the capacity of peritoneal macrophages to phagocyte using three different receptors: Fc, C3b and mannose receptors. We found a reduction in the phagocytosis of erythrocytes and Candida albicans related to the Fc and mannose receptors. These differences can be due to a macrophage reprogramming, as demonstrated by altered expression of cytokines and chemokines. Despite this reduction in phagocytosis capacity, macrophages from tolerant animals exhibited enhanced hydrogen peroxide production and expression of antigen presentation molecules, suggesting that their ability to combat an infection is improved. In summary, our data indicates that LPS tolerance drives macrophages from a predominant release of proinflammatory mediators that amplify inflammation and host damage toward a better killing and antigen presentation state.
- Short-term Obesity Worsens Heart Inflammation and Disrupts Mitochondrial Biogenesis and Function in an Experimental Model of Endotoxemia(2022) PETRONI, Ricardo Costa; OLIVEIRA, Suelen Jeronymo Souza de; FUNGARO, Thais Pineda; ARIGA, Suely K. K.; BARBEIRO, Hermes Vieira; SORIANO, Francisco Garcia; LIMA, Thais Martins deCardiomyopathy is a well-known complication of sepsis that may deteriorate when accompanied by obesity. To test this hypothesis we fed C57black/6 male mice for 6 week with a high fat diet (60% energy) and submitted them to endotoxemic shock using E. coli LPS (10 mg/kg). Inflammatory markers (cytokines and adhesion molecules) were determined in plasma and heart tissue, as well as heart mitochondrial biogenesis and function. Obesity markedly shortened the survival rate of mouse after LPS injection and induced a persistent systemic inflammation since TNF alpha, IL-1 beta, IL-6 and resistin plasma levels were higher 24 h after LPS injection. Heart tissue inflammation was significantly higher in obese mice, as detected by elevated mRNA expression of pro-inflammatory cytokines (IL-1 beta, IL-6 and TNF alpha). Obese animals presented reduced maximum respiratory rate after LPS injection, however fatty acid oxidation increased in both groups. LPS decreased mitochondrial DNA content and mitochondria biogenesis factors, such as PGC1 alpha and PGC1 beta, in both groups, while NRF1 expression was significantly stimulated in obese mice hearts. Mitochondrial fusion/fission balance was only altered by obesity, with no influence of endotoxemia. Obesity accelerated endotoxemia death rate due to higher systemic inflammation and decreased heart mitochondrial respiratory capacity.
- IMPACT OF TIME ON FLUID RESUSCITATION WITH HYPERTONIC SALINE (NACL 7.5%) IN RATS WITH LPS-INDUCED ACUTE LUNG INJURY(2015) PETRONI, Ricardo Costa; BISELLI, Paolo Jose Cesare; LIMA, Thais Martins de; VELASCO, Irineu Tadeu; SORIANO, Francisco GarciaAcute lung injury (ALI) is a common complication associated with septic shock that directly influences the prognosis of sepsis patients. Currently, one of the main supportive treatment modalities for septic shock is fluid resuscitation. The use of hypertonic saline (HS: 7.5% NaCl) for fluid resuscitation has been described as a promising therapy in experimental models of sepsis-induced ALI, but it has failed to produce similar results in clinical practice. Thus, we compared experimental timing versus clinical timing effectiveness (i.e., early vs. late fluid resuscitation) after the inflammatory scenario was established in a rat model of bacterial lipopolysaccharide-induced ALI. We found that late fluid resuscitation with hypertonic saline (NaCl 7.5%) did not reduce the mortality rates of animals compared with the mortality late associated with early treatment. Late fluid resuscitation with both hypertonic and normal saline increased pulmonary inflammation, decreased pulmonary function, and induced pulmonary injury by elevating metalloproteinase-2 and metalloproteinase-9 activity and collagen deposition in the animals, unlike early treatment. The animals with lipopolysaccharide-induced ALI that received late resuscitation with any kind of fluids demonstrated aggravated pulmonary injury and respiratory function. Moreover, we showed that the therapeutic window for a beneficial effect of fluid resuscitation with hypertonic saline is very narrow.
- Hypertonic Saline (NaCl 7.5 %) Reduces LPS-Induced Acute Lung Injury in Rats(2015) PETRONI, Ricardo Costa; BISELLI, Paolo Jose Cesare; LIMA, Thais Martins de; THEOBALDO, Mariana Cardillo; CALDINI, Elia Tamaso; PIMENTEL, Rosangela Nascimento; BARBEIRO, Hermes Vieira; KUBO, Suely Ariga; VELASCO, Irineu Tadeu; SORIANO, Francisco GarciaAcute respiratory distress syndrome (ARDS) is the most severe lung inflammatory manifestation and has no effective therapy nowadays. Sepsis is one of the main illnesses among ARDS causes. The use of fluid resuscitation is an important treatment for sepsis, but positive fluid balance may induce pulmonary injury. As an alternative, fluid resuscitation with hypertonic saline ((HS) NaCl 7.5 %) has been described as a promising therapeutical agent in sepsis-induced ARDS by the diminished amount of fluid necessary. Thus, we evaluated the effect of hypertonic saline in the treatment of LPS-induced ARDS. We found that hypertonic saline (NaCl 7.5 %) treatment in rat model of LPS-induced ARDS avoided pulmonary function worsening and inhibited type I collagen deposition. In addition, hypertonic saline prevented pulmonary injury by decreasing metalloproteinase 9 (MMP-9) activity in tissue. Focal adhesion kinase (FAK) activation was reduced in HS group as well as neutrophil infiltration, NOS2 expression and NO content. Our study shows that fluid resuscitation with hypertonic saline decreases the progression of LPS-induced ARDS due to inhibition of pulmonary remodeling that is observed when regular saline is used.