FASTING INCREASES THE SEVERITY OF ACUTE PANCREATITIS IN A MOUSE MODEL: IMPLICATIONS FOR PREOPERATIVE INTERVENTIONS TO REDUCE COMPLICATIONS OF PANCREATIC SURGERY.

BACKGROUND: Acute pancreatitis following surgical or endoscopic procedures on the pancreas can compromise the outcome and lead to severe complications and even death. The aim of this study was to determine whether prolonged fasting affects the severity of acute pancreatitis (AP). METHODS: Male mice were divided into 4 groups: Group CF (n=5) control animals that fasted for 24 hours; Group CNF (n=5) control animals that did not fast; Group APF (n=7) that fasted for 24 hours and underwent induction of acute pancreatitis (AP) and Group APNF (n=7) that did not fast and underwent AP. Eight hours after AP blood was collected for evaluation of cytokines: IL-1ß, IL-6, IL-10, TNF-α and MCP-1. Liver tissue was collected for determination of Malondialdehyde, pancreatic tissue for determination of enzyme content and lung tissue for determination of myeloperoxidase. RESULTS: Significant increase in pancreatic amylase content was observed in group CF and increased serum levels of IL -6, Il-10 and MCP-1 were in group APF. Liver malondialdehyde was also increased in APF animals. APF group showed much more necrosis of the pancreatic acinar cells. CONCLUSION: In the present study, we observed an increase in the severity of acute pancreatitis with prolonged fasting in a severe acute pancreatitis model. These results suggest that in clinical practice, the preoperative fasting time should be shortened before pancreatic procedures.

SEPTIC SHOCK: LPS TOLERANCE PROTECTS MITOCHONDRIAL BIOGENESIS AND RESPIRATION.

ABSTRACT: Mitochondrial dysfunction is a recognized feature of sepsis, characterized by ultrastructural damage, diminished oxidative phosphorylation, and depletion of mitochondrial antioxidant capacity observed in deceased septic patients. LPS tolerance induces a controlled response to sepsis. This study aimed to evaluate the function of tolerant mitochondria after cecal ligation and puncture (CLP)-induced sepsis. Mytochondrial oxygen consumption was determined using polarography. Extraction and quantification of RNA for the expression of Tfam, Nrf-1, and Ppargc-1α, and respiratory complex activity were measured. CLP-tolerant animals presented preserved respiratory rates of S3 and S4 and a ratio of respiratory control (RCR) compared to CLP-nontolerant animals with reduced oxidative phosphorylation and increased uncoupled respiration. Complex I Vmax was reduced in septic animals; however, CLP animals sustained normal Vmax. Mitochondrial biogenesis was preserved in CLP-tolerant animals compared to the CLP-nontolerant group, likely due to increased TFAM expression. LPS tolerance protected septic animals from mitochondrial dysfunction, favoring mitochondrial biogenesis and preserving mitochondrial respiration and respiratory complex I activity.

The Prolonged Activation of the p65 Subunit of the NF-Kappa-B Nuclear Factor Sustains the Persistent Effect of Advanced Glycation End Products on Inflammatory Sensitization in Macrophages.

Advanced glycation end products (AGEs) prime macrophages for lipopolysaccharide (LPS)-induced inflammation. We investigated the persistence of cellular AGE-sensitization to LPS, considering the nuclear content of p50 and p65 nuclear factor kappa B (NFKB) subunits and the expression of inflammatory genes. Macrophages treated with control (C) or AGE-albumin were rested for varying intervals in medium alone before being incubated with LPS. Comparisons were made using one-way ANOVA or Student t-test (n = 6). AGE-albumin primed macrophages for increased responsiveness to LPS, resulting in elevated levels of TNF, IL-6, and IL-1beta (1.5%, 9.4%, and 5.6%, respectively), compared to C-albumin. TNF, IL-6, and IL-1 beta secretion persisted for up to 24 h even after the removal of AGE-albumin (area under the curve greater by 1.6, 16, and 5.2 times, respectively). The expressions of Il6 and RelA were higher 8 h after albumin removal, and Il6 and Abca1 were higher 24 h after albumin removal. The nuclear content of p50 remained similar, but p65 showed a sustained increase (2.9 times) for up to 24 h in AGE-albumin-treated cells. The prolonged activation of the p65 subunit of NFKB contributes to the persistent effect of AGEs on macrophage inflammatory priming, which could be targeted for therapies to prevent complications based on the AGE-RAGE-NFKB axis.

Antimicrobial peptides and other potential biomarkers of critical illness in SARS-CoV-2 patients with acute kidney injury. AMPAKI-CoV study.

Antimicrobial peptides (AMPs) constitute a complex network of 10-100 amino acid sequence molecules widely distributed in nature. While over 300 AMPs have been described in mammals, cathelicidins and defensins remain the most extensively studied. Some publications have explored the role of AMPs in COVID-19, but these findings are preliminary, and in vivo studies are still lacking. In this study, we report the plasma levels of five AMPs (LL-37, α-defensin 1, α-defensin 3, ß-defensin 1, and ß-defensin 3), using the ELISA technique (MyBioSource, San Diego, CA, United States, kits MBS2601339 (beta-defensin 1), MBS2602513 (beta-defensin 3), MBS703879 (alpha-defensin 1), MBS706289 (alpha-defensin 3), MBS7234921 (LL37)), and the measurement of six cytokines (tumor necrosis factor-α, interleukin-1ß, interleukin-6, interleukin-10, interferon-γ, and monocyte chemoattractant protein-1), through the magnetic bead immunoassay Milliplex® and the MAGPIX® System (MilliporeSigma, Darmstadt, Germany, kit HCYTOMAG-60 K (cytokines)), in 15 healthy volunteers, 36 COVID-19 patients without Acute Kidney Injury (AKI) and 17 COVID-19 patients with AKI. We found increased levels of α-defensin 1, α-defensin 3 and ß-defensin 3, in our COVID-19 population, when compared to healthy controls, along with higher levels of interleukin-6, interleukin-10, interferon-γ, and monocyte chemoattractant protein-1. These findings suggest that these AMPs and cytokines may play a crucial role in the systemic inflammatory response and tissue damage characterizing severe COVID-19. The levels of α-defensin 1 and α-defensin 3 were significantly higher in COVID-19 AKI group in comparison to the non-AKI group. Furthermore, IL-10 and the product IL-10 × IL-1B showed excellent performance in discriminating AKI, with AUCs of 0.86 and 0.88, respectively. Among patients with COVID-19, AMPs may play a key role in the inflammation process and disease progression. Additionally, α-defensin 1 and α-defensin 3 may mediate the AKI process in these patients, representing an opportunity for further research and potential therapeutic alternatives in the future.

Jejum aumenta a gravidade da pancreatite aguda em camundongos: implicações para intervenções pré-operatórias para reduzir as complicações da cirurgia pancreática / Fasting increases the severity of acute pancreatitis in a mouse model: implications for preoperative interventions to reduce complications of pancreatic surgery

ABSTRACT Background: Acute pancreatitis following surgical or endoscopic procedures on the pancreas can compromise the outcome and lead to severe complications and even death. The aim of this study was to determine whether prolonged fasting affects the severity of acute pancreatitis (AP). Methods: Male mice were divided into 4 groups: Group CF (n=5) control animals that fasted for 24 hours; Group CNF (n=5) control animals that did not fast; Group APF (n=7) that fasted for 24 hours and underwent induction of acute pancreatitis (AP) and Group APNF (n=7) that did not fast and underwent AP. Eight hours after AP blood was collected for evaluation of cytokines: IL-1β, IL-6, IL-10, TNF-α and MCP-1. Liver tissue was collected for determination of Malondialdehyde, pancreatic tissue for determination of enzyme content and lung tissue for determination of myeloperoxidase. Results: Significant increase in pancreatic amylase content was observed in group CF and increased serum levels of IL -6, Il-10 and MCP-1 were in group APF. Liver malondialdehyde was also increased in APF animals. APF group showed much more necrosis of the pancreatic acinar cells. Conclusion: In the present study, we observed an increase in the severity of acute pancreatitis with prolonged fasting in a severe acute pancreatitis model. These results suggest that in clinical practice, the preoperative fasting time should be shortened before pancreatic procedures.

RESUMO Contexto: A pancreatite aguda após procedimentos cirúrgicos ou endoscópicos no pâncreas pode comprometer o resultado e levar a complicações graves e até mesmo à morte. O objetivo deste estudo foi determinar se o jejum prolongado afeta a gravidade da pancreatite aguda (PA). Métodos: Camundongos machos foram divididos em 4 grupos: Grupo CF (n=5) animais de controle que jejuaram por 24 horas; Grupo CNF (n=5) animais de controle que não jejuaram; Grupo APF (n=7) que jejuaram por 24 horas e foram submetidos à indução de PA e Grupo APNF (n=7) que não jejuaram e foram submetidos a PA. Oito horas após a PA, o sangue foi coletado para avaliação de citocinas: IL-1β, IL-6, IL-10, TNF-α e MCP-1. O tecido hepático foi coletado para a determinação do malondialdeído, o tecido pancreático para a determinação do conteúdo enzimático e o tecido pulmonar para a determinação da mieloperoxidase. Resultados: Foi observado um aumento significativo no conteúdo de amilase pancreática no grupo CF e um aumento nos níveis séricos de IL-6, Il-10 e MCP-1 no grupo APF. O malondialdeído hepático também aumentou nos animais APF. O grupo APF apresentou muito mais necrose das células acinares pancreáticas. Conclusão: No presente estudo, observamos um aumento na gravidade da pancreatite aguda com o jejum prolongado em um modelo de pancreatite aguda grave. Esses resultados sugerem que, na prática clínica, o tempo de jejum pré-operatório deve ser reduzido antes dos procedimentos pancreáticos.

Does fasting protect liver from ischemia and reperfusion injury?

PURPOSE: To evaluate local and systemic effects of 24-hour fasting in liver ischemia and reperfusion injury. METHODS: Twenty-one adult male Wistar rats (330-390 g) were submitted to 60 minutes of hepatic ischemia followed by 24 hours of reperfusion. Before the day of the experiment, the animals fasted, but free access to water was allowed. Two groups were constituted: Control: non-fasted, that is, feeding ad libitum before surgical procedure; Fasting: rats underwent previous fasting of 24 hours. Hepatic ischemia was performed using vascular clamp in hepatic pedicle. At 24 hours after liver reperfusion, blood and tissue samples were collected. To analysis, liver lobes submitted to ischemia was identified as ischemic liver and paracaval non-ischemic lobes as non-ischemic liver. We evaluated: malondialdehyde levels, hepatocellular function (alanine aminotransferase, aspartate aminotransferase activities, and both ratio), cytokines (interleukins-6, -10, and tumor necrosis factor-alpha), hepatic ischemia and reperfusion injury (histology). RESULTS: Malondialdehyde measured in non-ischemic and ischemic liver samples, hepatocellular function and cytokines were comparable between groups. Histological findings were distinct in three regions evaluated. Microvesicular steatosis was comparable between 24-hour fasting and non-fasted control groups in periportal region of hepatic lobe. In contrast, steatosis was more pronounced in zones 2 and 3 of ischemic liver samples of fasting compared to control groups. CONCLUSIONS: These data indicates that fasting does not protect, but it can be also detrimental to liver submitted to ischemia/reperfusion damage. At that time, using long fasting before liver surgery in the real world may be contraindicated.

Does fasting protect liver from ischemia and reperfusion injury?

Purpose: To evaluate local and systemic effects of 24-hour fasting in liver ischemia and reperfusion injury. Methods: Twenty-one adult male Wistar rats (330-390 g) were submitted to 60 minutes of hepatic ischemia followed by 24 hours of reperfusion. Before the day of the experiment, the animals fasted, but free access to water was allowed. Two groups were constituted: Control: non-fasted, that is, feeding ad libitum before surgical procedure; Fasting: rats underwent previous fasting of 24 hours. Hepatic ischemia was performed using vascular clamp in hepatic pedicle. At 24 hours after liver reperfusion, blood and tissue samples were collected. To analysis, liver lobes submitted to ischemia was identified as ischemic liver and paracaval non-ischemic lobes as non-ischemic liver. We evaluated: malondialdehyde levels, hepatocellular function (alanine aminotransferase, aspartate aminotransferase activities, and both ratio), cytokines (interleukins-6, -10, and tumor necrosis factor-alpha), hepatic ischemia and reperfusion injury (histology). Results: Malondialdehyde measured in non-ischemic and ischemic liver samples, hepatocellular function and cytokines were comparable between groups. Histological findings were distinct in three regions evaluated. Microvesicular steatosis was comparable between 24-hour fasting and non-fasted control groups in periportal region of hepatic lobe. In contrast, steatosis was more pronounced in zones 2 and 3 of ischemic liver samples of fasting compared to control groups. Conclusions: These data indicates that fasting does not protect, but it can be also detrimental to liver submitted to ischemia/reperfusion damage. At that time, using long fasting before liver surgery in the real world may be contraindicated.

Synbiotic Supplementation Modulates Gut Microbiota, Regulates ß-Catenin Expression and Prevents Weight Gain in ob/ob Mice: Preliminary Findings.

BACKGROUND: Obesity is one of the main health problems in the world today, and dysbiosis seems to be one of the factors involved. The aim of this study was to examine the impact of synbiotic supplementation on obesity and the microbiota in ob/ob mice. Twenty animals were divided into four groups: obese treated (OT), obese control (OC), lean treated (LT) and lean control (LC). All animals received a standard diet for 8 weeks. The treated groups received a synbiotic (Simbioflora-Invictus Farmanutrição Ltd., Sao Paulo, Brazil) in water, while the nontreated groups received only water. After 8 weeks, all animals were sacrificed, and gut tissue and stool samples were collected for mRNA isolation and microbiota analysis, respectively. ß-Catenin, occludin, cadherin and zonulin in the gut tissue were analyzed via RT-qPCR. Microbiome DNA was extracted from stool samples and sequenced using an Ion PGM Torrent platform. RESULTS: Synbiotic supplementation reduced body weight gain in the OT group compared with the OC group (p = 0.0398) and was associated with an increase in Enterobacteriaceae (p = 0.005) and a decrease in Cyanobacteria (p = 0.047), Clostridiaceae (p = 0.026), Turicibacterales (p = 0.005) and Coprococcus (p = 0.047). On the other hand, a significant reduction in Sutterella (p = 0.009) and Turicibacter (p = 0.005) bacteria was observed in the LT group compared to the LC group. Alpha and beta diversities were different among all treated groups. ß-Catenin gene expression was significantly decreased in the gut tissue of the OT group (p ≤ 0.0001) compared to the other groups. No changes were observed in occludin, cadherin or zonulin gene expression in the gut tissue. CONCLUSIONS: Synbiotic supplementation prevents excessive weight gain, modulates the gut microbiota, and reduces ß-catenin expression in ob/ob mice.

Crotoxin modulates inflammation and macrophages' functions in a murine sepsis model.

Sepsis is a syndrome of physiological and biochemical abnormalities induced by an infection that represents a major public health concern. It involves the early activation of inflammatory responses. Crotoxin (CTX), the major toxin of the South American rattlesnake Crotalus durissus terrificus venom, presents longstanding anti-inflammatory properties. Since immune system modulation may be a strategic target in sepsis management, and macrophages' functional and secretory activities are related to the disease's progression, we evaluated the effects of CTX on macrophages from septic animals. Balb/c male mice submitted to cecal ligation and puncture (CLP) were treated with CTX (0.9 µg/animal, subcutaneously) 1 h after the procedure and euthanized after 6 h. We used plasma samples to quantify circulating cytokines and eicosanoids. Bone marrow differentiated macrophages (BMDM) were used to evaluate the CTX effect on macrophages' functions. Our data show that CTX administration increased the survival rate of the animals from 40% to 80%. Septic mice presented lower plasma concentrations of IL-6 and TNF-α after CTX treatment, and higher concentrations of LXA4, PGE2, and IL-1ß. No effect was observed in IL-10, IFN-γ, and RD1 concentrations. BMDM from septic mice treated with CTX presented decreased capacity of E. coli phagocytosis, but sustained NO and H2O2 production. We also observed higher IL-6 concentration in the culture medium of BMDM from septic mice, and CTX induced a significant reduction. CTX treatment increased IL-10 production by macrophages as well. Our data show that the protective effect of CTX in sepsis mortality involves modulation of macrophage functions and inflammatory mediators' production.

Crotoxin modulates inflammation and macrophages’ functions in a murine sepsis model

Sepsis is a syndrome of physiological and biochemical abnormalities induced by an infection that represents a major public health concern. It involves the early activation of inflammatory responses. Crotoxin (CTX), the major toxin of the South American rattlesnake Crotalus durissus terrificus venom, presents longstanding anti-inflammatory properties. Since immune system modulation may be a strategic target in sepsis management, and macrophages' functional and secretory activities are related to the disease's progression, we evaluated the effects of CTX on macrophages from septic animals. Balb/c male mice submitted to cecal ligation and puncture (CLP) were treated with CTX (0.9 μg/animal, subcutaneously) 1 h after the procedure and euthanized after 6 h. We used plasma samples to quantify circulating cytokines and eicosanoids. Bone marrow differentiated macrophages (BMDM) were used to evaluate the CTX effect on macrophages' functions. Our data show that CTX administration increased the survival rate of the animals from 40% to 80%. Septic mice presented lower plasma concentrations of IL-6 and TNF-α after CTX treatment, and higher concentrations of LXA4, PGE2, and IL-1β. No effect was observed in IL-10, IFN-γ, and RD1 concentrations. BMDM from septic mice treated with CTX presented decreased capacity of E. coli phagocytosis, but sustained NO and H2O2 production. We also observed higher IL-6 concentration in the culture medium of BMDM from septic mice, and CTX induced a significant reduction. CTX treatment increased IL-10 production by macrophages as well. Our data show that the protective effect of CTX in sepsis mortality involves modulation of macrophage functions and inflammatory mediators’ production.

Th17/Treg-Related Intracellular Signaling in Patients with Chronic Obstructive Pulmonary Disease: Comparison between Local and Systemic Responses.

Th17/Treg imbalance plays a pivotal role in COPD development and progression. We aimed to assess Th17/Treg-related intracellular signaling at different COPD stages in local and systemic responses. Lung tissue and/or peripheral blood samples were collected and divided into non-obstructed (NOS), COPD stages I and II, and COPD stages III and IV groups. Gene expression of STAT3 and -5, RORγt, Foxp3, interleukin (IL)-6, -17, -10, and TGF-ß was assessed by RT-qPCR. IL-6, -17, -10, and TGF-ß levels were determined by ELISA. We observed increased STAT3, RORγt, Foxp3, IL-6, and TGF-ß gene expression and IL-6 levels in the lungs of COPD I and II patients compared to those of NOS patients. Regarding the systemic response, we observed increased STAT3, RORγt, IL-6, and TGF-ß gene expression in the COPD III and IV group and increased IL-6 levels in the COPD I and II group. STAT5 was increased in COPD III and IV patients, although there was a decrease in Foxp3 expression and IL-10 levels in the COPD I and II and COPD III and IV groups, respectively. We demonstrated that an increase in Th17 intracellular signaling in the lungs precedes this increase in the systemic response, whereas Treg intracellular signaling varies between the compartments analyzed in different COPD stages.

Cathelicidin protects mice from Rhabdomyolysis-induced Acute Kidney Injury.

Background: Cathelicidins are ancient and well-conserved antimicrobial peptides (AMPs) with intriguing immunomodulatory properties in both infectious and non-infectious inflammatory diseases. In addition to direct antimicrobial activity, cathelicidins also participate in several signaling pathways inducing both pro-inflammatory and anti-inflammatory effects. Acute kidney injury (AKI) is common in critically ill patients and is associated with high mortality and morbidity. Rhabdomyolysis is a major trigger of AKI. Objectives: Here, we investigated the role of cathelicidins in non-infectious Acute kidney Injury (AKI). Method: Using an experimental model of rhabdomyolysis, we induced AKI in wild-type and cathelicidin-related AMP knockout (CRAMP-/-) mice. Results: We previously demonstrated that CRAMP-/- mice, as opposed wild-type mice, are protected from AKI during sepsis induced by cecal ligation and puncture. Conversely, in the current study, we show that CRAMP-/- mice are more susceptible to the rhabdomyolysis model of AKI. A more in-depth investigation of wild-type and CRAMP-/- mice revealed important differences in the levels of several inflammatory mediators. Conclusion: Cathelicidins can induce a varied and even opposing repertoire of immune-inflammatory responses depending on the subjacent disease and the cellular context.

Chemical Characterization and Wound Healing Property of Jacaranda decurrens Cham. (Bignoniaceae): An Experimental Study Based on Molecular Mechanisms.

BACKGROUND: Jacaranda decurrens Cham., known as carobinha, is prevalent in the Cerrado biome and presents popular use in treatment of dermatological diseases. The present study aimed to investigate the healing action of topical formulation of Jacaranda decurrens Cham. (FtEHJ) in mice cutaneous lesions. METHODS: Phytochemical analysis of J. decurrens hydroalcoholic extract was carried out by using HPLC-PDA-ESI-MS and FIA-ESI-IT-MSn. Swiss mice were treated topically with formulation base (FtB) or Fibrinase® or ointment FtEHJ (15 mg/g; 50 mg/Kg). At the end of treatment periods, the inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in the lesions were measured by using ELISA and gene expression of TGF-ß, Collagen I, and Collagen III was demonstrated by RTqPCR method and histological evaluation. RESULTS: Ten compounds were identified in the extract, distributed among the classes of flavonoids and triterpenes. Treatment with FtEHJ increased the wound contraction in 24 hours, such as reduction of TNF-α, IL-1ß, and IL-6 (pg/mL) cytokines in the lesion. The TGF-ß and collagen gene expression was increased and the wound closure accelerated to nine days, with discrete inflammation, collagenization, and accented reepithelialization. Conclusions. The results obtained suggest chemical compounds present in the FtEHJ accelerates wound healing by being a gene expression modulator, and protein content of different molecules are involved in tissue repair.

Hypertonic solution-induced preconditioning reduces inflammation and mortality rate.

BACKGROUND: Dysregulated inflammatory response is common cause of organ damage in critical care patients. Preconditioning/tolerance is a strategy to prevent exacerbated inflammation. The aim of this study is to analyze hypertonic saline 7.5% as a potential inducer of preconditioning that protect from a lethal dose of LPS and modulates systemic inflammatory profile in mice. METHODS: Male Balb/C mice received intravenous (i.v.) injections of Hypertonic solution (NaCl 7.5%) (0.8 ml) for 3 days, on day 8th was challenged with LPS 15 mg/kg. Controls with Saline 0.9%, urea and sorbitol were performed. Microarray of mRNA expression was analyzed from HS versus saline from macrophages to identified the pathways activated by HS. RESULTS: HS preconditioning reduced mortality after LPS injection as well reduced the cytokines release in plasma of the animals challenged by LPS. In order to check how HS induces a preconditioning state we measured plasma cytokines after each HS infusion. Repeated HS injections induced a state of preconditioning that reprograms the inflammatory response, resulting in reduced inflammatory cytokine production. A microarray of mRNA demonstrated that Hypertonic solution increased the expression of several genes in special Mapkbp1 and Atf3. CONCLUSION: hypertonic solution induces preconditioning/tolerance reducing mortality and inflammatory response after LPS challenge.

Endotoxin tolerance modulates TREG and TH17 lymphocytes protecting septic mice.

Background: Tolerance induces a regulated immune response to infection. We hypothesized that tolerance induction modulated profile of T regulatory cell (Treg) and T lymphocyte 17 (Th17) cells and is related cytokine released in septic animals. Methods: Male black C57/6 mice received subcutaneous (s.c.) injections of lipopolysaccharide (LPS) (1 mg/kg) for 5 days, on day 8th was made cecal ligation and puncture (CLP). Blood and spleen tissue were collected for cell analysis and cytokines measurements. Results: Cytokines (interleukin 2 (IL-2), interleukin (IL-6), transforming growth factor ß (TGF-ß) and interferon γ (INF-γ)) related to Treg and Th17 stimulation were elevated in the spleen of tolerant animals compared to sham. Treg and Th17 lymphocytes showed an increased amount in blood (Treg: 920 ± 84 cells vs. 1946 ± 65 cells, sham vs. tolerant; Th17:38321± 1954 cells vs. 43526 ± 7623 cells, sham vs. tolerant) and spleen (Treg: 5947 ± 273 cells vs. 16521 ± 486 cells, sham vs. tolerant; Th17: 26543 ± 2944 cells vs. 64567 ± 5523 cells, sham vs. tolerant). Treg (135±23 cells) and Th17 (1590 ± 256 cells) cells were reduced in blood of septic animals compared to sham, while CLP tolerant animals presented an increasing number of these cells. Lymphocyte Th17IL6+ were elevated in tolerant and CLP tolerant animals in the blood compared to sham. Conclusion: LPS tolerance was associated with increasing population of Treg and Th17. LPS tolerance reduces the hyper inflammatory response with immunoregulation exerted by Treg and Th17 cells protecting from septic damage.

Short-Term Effects of Sepsis and the Impact of Aging on the Transcriptional Profile of Different Brain Regions.

Among the clinical manifestations observed in septic patients, sepsis-associated encephalopathy (SAE) is probably the most obscure and poorly explored. It is well established, however, that SAE is more prevalent in aged individuals and related to a worse outcome. In this context, we decided to investigate the acute effects of sepsis, induced by cecal ligation and puncture (CLP), on the cerebral transcriptional profile of young and old rats. The idea was to highlight important signaling pathways possibly implicated in the early stages of SAE. Global gene expression analysis of three different brain regions (hippocampus, cerebellum, and cortex) indicated a relatively small interference of sepsis at the transcriptional level. Cerebellum tissue was the least affected by sepsis in aged rats. The increased expression of S100a8, Upp1, and Mt2a in all three brain regions of young septic rats indicate that these genes may be involved in the first line of response to sepsis in the younger brain. On the other hand, altered expression of a network of genes involved in sensory perception of smell in the cortex of aged rats, but not in young ones, indicates an earlier disruption of cortex function, possibly more sensitive to the systemic inflammation. The expression of S100a8 at the protein level was confirmed in all brain regions, with clear-up regulation in septic aged cortex. Taken together, our results indicate that the transcriptional response of the central nervous system to early sepsis varies between distinct brain regions and that the cortex is affected earlier in aged animals, in line with early neurological manifestations observed in older patients.

Diazoxide reduces local and remote organ damage in a rat model of intestinal ischemia reperfusion.

BACKGROUND: Intestinal ischemia reperfusion is a common clinical condition that causes functional impairment. Once tight junctions are damaged, barrier function is compromised, and the intestines become a source for entry of bacterial and inflammatory mediators into the circulation, leading to systemic inflammatory response syndrome, multiple organ failure, and death. It is possible that diazoxide could protect the intestines against ischemia reperfusion. The aim of this study is to determine whether diazoxide can provide protection in a rat model of intestinal ischemia reperfusion. METHODS: A total of 32 adult male specific pathogen-free Wistar rats were randomized into three groups: a control group, n = 6; a saline group, n = 13; and a diazoxide group, n = 13. The saline and diazoxide groups underwent clamping of the superior mesenteric artery for 1 h, with samples in all the groups being collected 12 h later. RESULTS: Intestinal histology showed greater damage in the intestinal ischemia reperfusion groups. mRNA expression of zonula occludens-1 and occludin (tight junction proteins) and interleukin-6 and cyclooxygenase-2 was the highest in the Saline group. The Diazoxide group showed a reduction in aspartate aminotransferase serum levels compared with the other groups. CONCLUSIONS: Increased expression of zonula occludens-1, occludin, and cyclooxygenase-2 suggested a greater regenerative effort because of more severe lesions in the saline group. In addition, increased expression of interleukin-6 in the saline group was suggestive of inflammation, indicating that diazoxide had protective effects in the diazoxide group. Reduced aspartate aminotransferase in the diazoxide group suggested liver protection. Diazoxide protects the intestines and liver from intestinal ischemia reperfusion lesions in rats.

High-fat diet inhibits PGC-1α suppressive effect on NFκB signaling in hepatocytes.

PURPOSE: The peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) 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-1α exhibit lipid accumulation and high-fat diet reduces hepatic PGC-1α expression in mice. In this study, we investigated the role of PGC-1α in the inflammatory changes observed in steatohepatitis induced by high-fat diet. METHODS: 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-α, and IL-1ß quantification. Liver gene expression of PGC-1 isoforms was evaluated by real-time PCR and p65 NFκB 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-1α on inflammatory mediators' production by hepatocytes. RESULTS: 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-1α expression, and marked increase in p65 NFκB nuclear translocation. Linoleic acid treated cells also presented increased expression of proinflammatory cytokines and decreased PGC-1α expression. The knockdown of PGC-1α content caused an increase in IL-6 expression and release via enhanced IκBα phosphorylation and subsequent increase of p65 NFκB nuclear translocation. CONCLUSION: High-fat diet induces liver inflammation by inhibiting PGC-1α expression and its suppressive effect in NFκB pathway.

Cathelicidin-deficient mice exhibit increased survival and upregulation of key inflammatory response genes following cecal ligation and puncture.

Antimicrobial peptides possess a myriad of molecular properties including bacterial killing and the regulation of many aspects of innate immunity. Cathelicidins are a group of antimicrobial peptides widely investigated by the scientific community. Many studies have focused on the bactericidal and pro-inflammatory roles of cathelicidins. Because the role of endogenous cathelicidin expression remains obscure in deep-seated systemic infections, we induced sepsis in cathelicidin knockout and wild-type (WT) mice by cecal ligation and puncture, performing transcriptome screening by DNA microarray in conjunction with other immunologic assays. Cathelicidin-deficient mice showed increased survival compared to WT mice in this established experimental model of polymicrobial sepsis, in association with upregulation of certain key inflammatory response genes. Therefore, cathelicidins can exert both pro- and anti-inflammatory activities depending on the disease and cellular context. KEY MESSAGES: The role of cathelicidin in a CLP model is investigated using cathelicidin-KO mice. Cathelicidin-KO mice show an enhanced immune response and improved survival rates. An anti-inflammatory effect of cathelicidin is likely to be detrimental for CLP. Cathelicidin-KO mice show upregulation of genes associated with increased plasma levels of pro-inflammatory Ils. Cathelicidins appear to have both pro- and anti-inflammatory properties.

Low-sodium diet induces atherogenesis regardless of lowering blood pressure in hypertensive hyperlipidemic mice.

This study investigated the influence of sodium restriction and antihypertensive drugs on atherogenesis utilizing hypertensive (H) low-density lipoprotein-receptor knockout mice treated or not with losartan (Los) or hydralazine (Hyd) and fed low-sodium (LS) or normal-sodium (NS) chow. Despite reducing the blood pressure (BP) of H-LS mice, the LS diet caused arterial lipid infiltration due to increased plasma total cholesterol (TC) and triglycerides (TG). Los and Hyd reduced the BP of H-LS mice, and Los effectively prevented arterial injury, likely by reducing plasma TG and nonesterified fatty acids. Aortic lipid infiltration was lower in Los-treated H-LS mice (H-LS+Los) than in normotensive (N)-LS and H-LS mice. Aortic angiotensin II type 1 (AT1) receptor content was greater in H-NS than H-LS mice and in H-LS+Hyd than H-LS+Los mice. Carboxymethyl-lysine (CML) and receptor for advanced glycation end products (RAGE) immunostaining was greater in H-LS than H-NS mice. CML and RAGE levels were lower in LS animals treated with antihypertensive drugs, and Hyd enhanced the AT1 receptor level. Hyd also increased the gene expression of F4/80 but not tumor necrosis factor-α, interleukin (IL)-1ß, IL-6, IL-10, intercellular adhesion molecule-1 or cluster of differentiation 66. The novelty of the current study is that in a murine model of simultaneous hypertension and hyperlipidemia, the pleiotropic effect of chronic, severe sodium restriction elicited aortic damage even with reduced BP. These negative effects on the arterial wall were reduced by AT1 receptor antagonism, demonstrating the influence of angiotensin II in atherogenesis induced by a severely LS diet.