Prophylactic Minocycline for Delirium in Critically Ill Patients: A Randomized Controlled Trial.

BACKGROUND: Delirium is a potentially severe form of acute encephalopathy. Minocycline has neuroprotective effects in animal models of neurologic diseases; however, data from human studies remain scarce. RESEARCH QUESTION: Does the neuroprotective effect of minocycline prevent delirium occurrence in critical ill patients? STUDY DESIGN AND METHODS: This study was a randomized, placebo-controlled, double-blind trial conducted in four ICUs. Patients aged 18 years or older were eligible and randomized to receive minocycline (100 mg, twice daily) or placebo. The primary outcome was delirium incidence within 28 days or before ICU discharge. Secondary outcomes included days in delirium during ICU stay, delirium/coma-free days, length of mechanical ventilation, ICU length of stay, ICU mortality, and hospital mortality. The kinetics of various inflammatory (IL-1ß, IL-6, IL-10, and C-reactive protein) and brain-related biomarkers (brain-derived neurotrophic factor and S100B) were used as exploratory outcomes. RESULTS: A total of 160 patients were randomized, but one patient in the placebo group died before treatment; thus the data from 159 patients were analyzed (minocycline, n = 84; placebo, n = 75). After the COVID-19 pandemic it was decided to stop patient inclusion early. There was a small but significant decrease in delirium incidence: 17 patients (20%) in the minocycline arm compared with 26 patients (35%) in the placebo arm (P = .043). No other delirium-related outcomes were modified by minocycline treatment. Unexpectedly, there was a significant decrease in hospital mortality (39% vs. 23%; P = .029). Among all analyzed biomarkers, only plasma levels of C-reactive protein decreased significantly after minocycline treatment (F = 0.75, P = .78, within time; F = 4.09, P = .045, group × time). INTERPRETATION: Our findings in this rather small study signal a possible positive effect of minocycline on delirium incidence. Further studies are needed to confirm the benefits of this drug as a preventive measure in critically ill patients. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT04219735; URL: www. CLINICALTRIALS: gov.

Biomarkers of neuropsychiatric dysfunction in intensive care unit survivors: a prospective cohort study.

OBJECTIVE: To assess factors associated with long-term neuropsychiatric outcomes, including biomarkers measured after discharge from the intensive care unit. METHODS: A prospective cohort study was performed with 65 intensive care unit survivors. The cognitive evaluation was performed through the Mini-Mental State Examination, the symptoms of anxiety and depression were evaluated using the Hospital Anxiety and Depression Scale, and posttraumatic stress disorder was evaluated using the Impact of Event Scale-6. Plasma levels of amyloid-beta (1-42) [Aß (1-42)], Aß (1-40), interleukin (IL)-10, IL-6, IL-33, IL-4, IL-5, tumor necrosis factor alpha, C-reactive protein, and brain-derived neurotrophic factor were measured at intensive care unit discharge. RESULTS: Of the variables associated with intensive care, only delirium was independently related to the occurrence of long-term cognitive impairment. In addition, higher levels of IL-10 and IL-6 were associated with cognitive dysfunction. Only IL-6 was independently associated with depression. Mechanical ventilation, IL-33 levels, and C-reactive protein levels were independently associated with anxiety. No variables were independently associated with posttraumatic stress disorder. CONCLUSION: Cognitive dysfunction, as well as symptoms of depression, anxiety, and posttraumatic stress disorder, are present in patients who survive a critical illness, and some of these outcomes are associated with the levels of inflammatory biomarkers measured at discharge from the intensive care unit.

Coagulation biomarkers and coronavirus disease 2019 phenotyping: a prospective cohort study.

BACKGROUND: Because severe acute respiratory syndrome coronarivus 2 (SARS-CoV-2) leads to severe conditions and thrombus formation, evaluation of the coagulation markers is important in determining the prognosis and phenotyping of patients with COVID-19. METHODS: In a prospective study that included 213 COVID-19 patients admitted to the intensive care unit (ICU) the levels of antithrombin, C-reactive protein (CRP); factors XI, XII, XIII; prothrombin and D-dimer were measured. Spearman's correlation coefficient was used to assess the pairwise correlations between the biomarkers. Hierarchical and non-hierarchical cluster analysis was performed using the levels of biomarkers to identify patients´ phenotypes. Multivariate binary regression was used to determine the association of the patient´s outcome with clinical variables and biomarker levels. RESULTS: The levels of factors XI and XIII were significantly higher in patients with less severe COVID-19, while factor XIII and antithrombin levels were significantly associated with mortality. These coagulation biomarkers were associated with the in-hospital survival of COVID-19 patients over and above the core clinical factors on admission. Hierarchical cluster analysis showed a cluster between factor XIII and antithrombin, and this hierarchical cluster was extended to CRP in the next step. Furthermore, a non-hierarchical K-means cluster analysis was performed, and two phenotypes were identified based on the CRP and antithrombin levels independently of clinical variables and were associated with mortality. CONCLUSION: Coagulation biomarkers were associated with in-hospital survival of COVID-19 patients. Lower levels of factors XI, XII and XIII and prothrombin were associated with disease severity, while higher levels of both CRP and antithrombin clustered with worse prognosis. These results suggest the role of coagulation abnormalities in the development of COVID-19 and open the perspective of identifying subgroups of patients who would benefit more from interventions focused on regulating coagulation.

Neurochemical effects of sepsis on the brain.

Sepsis is a life-threatening organ dysfunction triggered by a dysregulated host immune response to eliminate an infection. After the host immune response is activated, a complex, dynamic, and time-dependent process is triggered. This process promotes the production of inflammatory mediators, including acute-phase proteins, complement system proteins, cytokines, chemokines, and antimicrobial peptides, which are required to initiate an inflammatory environment for eliminating the invading pathogen. The physiological response of this sepsis-induced systemic inflammation can affect blood-brain barrier (BBB) function; subsequently, endothelial cells produce inflammatory mediators, including cytokines, chemokines, and matrix metalloproteinases (MMPs) that degrade tight junction (TJ) proteins and decrease BBB function. The resulting BBB permeability allows peripheral immune cells from the bloodstream to enter the brain, which then release a range of inflammatory mediators and activate glial cells. The activated microglia and astrocytes release reactive oxygen species (ROS), cytokines, chemokines, and neurochemicals, initiate mitochondrial dysfunction and neuronal damage, and exacerbate the inflammatory milieu in the brain. These changes trigger sepsis-associated encephalopathy (SAE), which has the potential to increase cognitive deterioration and susceptibility to cognitive decline later in life.

Biomarkers of neuropsychiatric dysfunction in intensive care unit survivors: a prospective cohort study / Biomarcadores de disfunção neuropsiquiátrica em sobreviventes de unidades de terapia intensiva: um estudo de coorte prospectivo

ABSTRACT Objective: To assess factors associated with long-term neuropsychiatric outcomes, including biomarkers measured after discharge from the intensive care unit. Methods: A prospective cohort study was performed with 65 intensive care unit survivors. The cognitive evaluation was performed through the Mini-Mental State Examination, the symptoms of anxiety and depression were evaluated using the Hospital Anxiety and Depression Scale, and posttraumatic stress disorder was evaluated using the Impact of Event Scale-6. Plasma levels of amyloid-beta (1-42) [Aβ (1-42)], Aβ (1-40), interleukin (IL)-10, IL-6, IL-33, IL-4, IL-5, tumor necrosis factor alpha, C-reactive protein, and brain-derived neurotrophic factor were measured at intensive care unit discharge. Results: Of the variables associated with intensive care, only delirium was independently related to the occurrence of long-term cognitive impairment. In addition, higher levels of IL-10 and IL-6 were associated with cognitive dysfunction. Only IL-6 was independently associated with depression. Mechanical ventilation, IL-33 levels, and C-reactive protein levels were independently associated with anxiety. No variables were independently associated with posttraumatic stress disorder. Conclusion: Cognitive dysfunction, as well as symptoms of depression, anxiety, and posttraumatic stress disorder, are present in patients who survive a critical illness, and some of these outcomes are associated with the levels of inflammatory biomarkers measured at discharge from the intensive care unit.

RESUMO Objetivo: Avaliar os fatores associados aos desfechos neuropsiquiátricos de longo prazo, incluindo biomarcadores, medidos após a alta da unidade de terapia intensiva. Métodos: Foi realizado um estudo de coorte prospectivo com 65 sobreviventes de unidades de terapia intensiva. A avaliação cognitiva foi realizada por meio do Miniexame do Estado Mental; os sintomas de ansiedade e depressão foram avaliados por meio da Escala Hospitalar de Ansiedade e Depressão, e o transtorno de estresse pós-traumático foi avaliado pela Escala de Impacto do Evento-6. Os níveis plasmáticos de beta amiloide (1-42), beta amiloide (1-40), interleucina 10, interleucina 6, interleucina 33, interleucina 4, interleucina 5, fator de necrose tumoral alfa, proteína C-reativa e fator neurotrófico derivado do cérebro foram medidos na alta da unidade de terapia intensiva. Resultados: Das variáveis associadas à terapia intensiva, apenas o delirium foi relacionado de forma independente à ocorrência de comprometimento cognitivo de longo prazo. Além disso, níveis mais altos de interleucina 10 e interleucina 6 foram associados à disfunção cognitiva. Apenas a interleucina 6 foi associada de forma independente à depressão. A ventilação mecânica, os níveis de interleucina 33 e os níveis de proteína C-reativa foram associados de forma independente à ansiedade. Nenhuma variável foi associada de forma independente ao transtorno de estresse pós-traumático. Conclusão: A disfunção cognitiva, bem como os sintomas de depressão, ansiedade e transtorno de estresse pós-traumático, estão presentes em pacientes que sobrevivem a uma doença grave, e alguns desses desfechos estão associados aos níveis de biomarcadores inflamatórios medidos na alta da unidade de terapia intensiva.

Respiratory Outcomes After 6 Months of Hospital Discharge in Patients Affected by COVID-19: A Prospective Cohort.

Background: Considering millions of people affected by Coronavirus disease 2019 (COVID-19), long-lasting sequelae can significantly impact health worldwide. Data from prospective studies in lower-middle-income countries on persistent lung dysfunction secondary to COVID-19 are lacking. This work aims to determine risk factors and the impact of persistent lung dysfunctions in COVID-19 survivors. Methods: Observational and prospective cohort of patients admitted to a tertiary hospital from June 2020 to November 2020. Persistence of chest CT scan alterations, desaturation in the six-minute walk test (6MWT), forced expiratory volume in one second (FEV1), lung carbon monoxide diffusion (DLCO), and maximum inspiratory pressure (MIP) were measured 6 months after hospital discharge. Additionally, the Barthel index (BI) and the Modified Medical Research Council (mMRC) Dyspnea Scale were used to determine the impact of lung dysfunction in activities of daily living (ADL). Results: It was included 44 patients. Sixty percent had persistent lung CT scan abnormalities. From 18 to 43% of patients had at least one pulmonary function dysfunction, a decrease in FEV1 was the least prevalent (18%), and a reduction in DLCO and MIP was the most frequent (43%). In general, female gender, comorbidity index, and age were associated with worse lung function. Additionally, the presence of lung dysfunction could predict worse BI (r-square 0.28) and mMRC (r-square 0.32). Conclusion: Long-term lung dysfunction is relatively common in survivors from severe COVID-19 and impacts negatively on ADL and the intensity of dyspnea, similar to studies in high-income countries.

Comparative effects of fresh and sterile fecal microbiota transplantation in an experimental animal model of necrotizing enterocolitis.

INTRODUCTION: Necrotizing Enterocolitis (NEC) is a serious intestinal disease that affects premature neonates, causing high mortality, despite the technological development in neonatal intensive care, with antibiotics, parenteral nutrition, surgery, and advanced life support. The correction of dysbiosis with fecal microbiome transplantation (FMT) has shown beneficial effects in experimental models of the disease. The different forms of administration and conservation of FMT and mixed results depending on several factors lead to questions about the mechanism of action of FMT. This study aimed to compare the effectiveness of fresh, sterile FMT and probiotic treatment under parameters of inflammation, oxidative stress, and tissue damage in a neonatal model of NEC. METHODS: One-day-old Wistar rats were used to induce NEC model. Animals were divided in five groups: Control + saline; NEC + saline; NEC + fresh FMT; NEC + sterile FMT and NEC+ probiotics. Parameters of inflammatory response and oxidative damage were measured in the gut, brain, and serum. It was also determined gut histopathological alterations. RESULTS: Proinflammatory cytokines were increased in the NEC group, and IL-10 levels decreased in the gut, brain, and serum. Fresh and sterile FMT decreased inflammation when compared to the use of probiotics. Oxidative and histological damage to the intestine was apparent in the NEC group, and both FMT treatments had a protective effect. CONCLUSION: Fresh and sterile FMT effectively reduced the inflammatory response, oxidative damage, and histological alterations in the gut and brain compared to an experimental NEC model.

Clinical efficacy of capsules containing standardized extract of Bauhinia forficata Link (pata-de-vaca) as adjuvant treatment in type 2 diabetes patients: A randomized, double blind clinical trial.

ETHNOPHARMACOLOGICAL RELEVANCE: Bauhinia forficata Link, is a Brazilian native plant and popularly known as pata-de-vaca ("paw-of-cow"). The tea prepared with their leaves has been extensively used in the Brazilian traditional practices for the diabetes treatment. The aim of the present study was to investigate the effect of capsules containing granules of a standardized extract of B. forficata leaves as adjuvant treatment on the glycemic control of patients with type-2 diabetes melitus. MATERIALS AND METHODS: A double-blind, randomized clinical trial using capsules containing granules prepared by wet granulation of a standardized extract from B. forficata leaves as adjuvant treatment, was conducted. 92 patients aged 18-75 years from an outpatient clinic with type-2 diabetes were randomly assigned by a simple randomization scheme, in a 1:1 ratio to receive capsules of B. forficata or placebo for four months. The capsules used contain 300 mg of standardized extract from B. forficata leaves, yielding 2% of total flavonoid content per capsule. Primary outcome was glycated hemoglobin levels and fasting plasma glucose at 4 months. Possible harms were also determined. RESULTS: The findings showed that at 4 months, the mean fasting plasma glucose levels and glycated hemoglobin were both significantly lower in the B. forficata group than in the placebo group. CONCLUSION: The present study suggests that the adjunctive use of capsules containing standardized extract of B. forficata can add to regular oral anti-diabetics in the metabolic and inflammatory control of type-2 diabetes patients.

Postmortem Evidence of Brain Inflammatory Markers and Injury in Septic Patients: A Systematic Review.

OBJECTIVES: Sepsis is a life-threatening organ dysfunction caused by a host's unregulated immune response to eliminate the infection. After hospitalization, sepsis survivors often suffer from long-term impairments in memory, attention, verbal fluency, and executive functioning. To understand the effects of sepsis and the exacerbated peripheral inflammatory response in the brain, we asked the question: What are the findings and inflammatory markers in the brains of deceased sepsis patients? To answer this question, we conducted this systematic review by the recommendations of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. DATA SOURCES: Relevant studies were identified by searching the PubMed/National Library of Medicine, PsycINFO, EMBASE, Bibliographical Index in Spanish in Health Sciences, Latin American and Caribbean Health Sciences Literature, and Web of Science databases for peer-reviewed journal articles published on April 05, 2021. STUDY SELECTION: A total of 3,745 articles were included in the primary screening; after omitting duplicate articles, animal models, and reviews, 2,896 articles were selected for the study. These studies were selected based on the title and abstract, and 2,772 articles were still omitted based on the exclusion criteria. DATA EXTRACTION: The complete texts of the remaining 124 articles were obtained and thoroughly evaluated for the final screening, and 104 articles were included. DATA SYNTHESIS: The postmortem brain had edema, abscess, hemorrhagic and ischemic injuries, infarction, hypoxia, atrophy, hypoplasia, neuronal loss, axonal injuries, demyelination, and necrosis. CONCLUSIONS: The mechanisms by which sepsis induces brain dysfunction are likely to include vascular and neuronal lesions, followed by the activation of glial cells and the presence of peripheral immune cells in the brain.

Association of uteroglobin-related protein 1 with smoke inhalation injury severity. / Associação entre proteína 1 relacionada à uteroglobulina e gravidade da lesão por inalação de fumaça.

OBJECTIVE: To evaluate serum uteroglobin-related protein 1 expression early after smoke inhalation injuries and its association with the severity of inhalation injury in burned patients. METHODS: Smoke or chemical inhalation injury is associated with morbidity and mortality. The consequences of inhalation result from an inflammatory response. Uteroglobin-related protein 1 is an anti-inflammatory protein and may improve lung inflammation. We hypothesized that uteroglobin-related protein 1 levels could reflect disease severity and predict outcome in patients with inhalation injury. Sixteen patients diagnosed with acute respiratory distress syndrome secondary to smoke inhalation injury were prospectively included in the study. Plasma was collected upon intensive care unit admission and within 24 hours of the inhalation injury. Bronchoscopies were carried out in all patients to assess the severity of inhalation injury within 72 hours. Uteroglobin-related protein 1 plasma levels were determined in duplicate with enzyme-linked immunosorbent assay. RESULTS: The mean age was 23 ± 5 years, and the inhalation injury distribution was as follows: three of grade 1, four of grade 2, and nine of grade 3. The level of uteroglobin-related protein 1 was related to inhalation severity (grade 1: 0.389 ± 0.053 arbitrary units versus grade 2: 0.474 ± 0.0423 arbitrary units versus grade 3: 0.580 ± 0.094 arbitrary units; p = 0.007). CONCLUSION: Plasma levels of uteroglobin-related protein 1 are associated with the degree of lung inhalation injury.

OBJETIVO: Avaliar a expressão sérica da proteína 1 relacionada à uteroglobulina na fase inicial após lesões por inalação de fumaça e sua associação com a gravidade da lesão por inalação em pacientes queimados. MÉTODOS: A lesão por inalação de fumaça ou produtos químicos se associa com morbidade e mortalidade. As consequências da inalação resultam de uma resposta inflamatória. A proteína 1 relacionada à uteroglobulina é anti-inflamatória e pode melhorar a inflamação pulmonar. Nossa hipótese é que os níveis de proteína 1 relacionada à uteroglobulina podem refletir a gravidade da doença e predizer o desfecho em pacientes com lesão por inalação. Incluíram-se prospectivamente neste estudo 16 pacientes com diagnóstico de síndrome do desconforto respiratório agudo decorrente de lesão por inalação de fumaça. Em todos os pacientes, colheu-se amostra de plasma quando da admissão à unidade de terapia intensiva, para avaliar a gravidade da lesão por inalação dentro de 72 horas. Os níveis plasmáticos de proteína 1 relacionada à uteroglobulina foram determinados em duplicata por meio de ensaio de imunoabsorção ligado à enzima. RESULTADOS: A média de idade foi de 23 ± 5 anos, e a distribuição da lesão por inalação foi: três em grau 1, quatro em grau 2 e nove em grau 3. O nível de proteína 1 relacionada à uteroglobulina foi relacionado ao grau de severidade (grau 1: 0,389 ± 0,053 unidade arbitrária versus grau 2: 0,474 ± 0,0423 unidade arbitrária versus grau 3: 0,580 ± 0,094 unidade arbitrária; p = 0,007). CONCLUSÃO: Os níveis plasmáticos de proteína 1 relacionada à uteroglobulina se associam com o grau da lesão pulmonar por inalação.

The effects of anaesthetics and sedatives on brain inflammation.

Microglia are involved in many dynamic processes in the central nervous system (CNS) including the development of inflammatory processes and neuromodulation. Several sedative, analgesic or anaesthetic drugs, such as opioids, ∝2-adrenergic agonists, ketamine, benzodiazepines and propofol can cause both neuroprotective and harmful effects on the brain. The purpose of this review is to present the main findings on the use of these drugs and the mechanisms involved in microglial activation. Alpha 2-adrenergic agonists, propofol and benzodiazepines have several pro- or anti-inflammatory effects on microglia. Long-term use of benzodiazepines and propofol causes neuroapoptotic effects and α2-adrenergic agonists may attenuate these effects. Conversely, morphine and fentanyl may have proinflammatory effects, causing behavioural changes in patients and changes in cell viability in vitro. Conversely, chronic administration of morphine induces CCL5 chemokine expression in microglial cells that promotes their survival.

Associação entre proteína 1 relacionada à uteroglobulina e gravidade da lesão por inalação de fumaça / Association of uteroglobin-related protein 1 with smoke inhalation injury severity

RESUMO Objetivo: Avaliar a expressão sérica da proteína 1 relacionada à uteroglobulina na fase inicial após lesões por inalação de fumaça e sua associação com a gravidade da lesão por inalação em pacientes queimados. Métodos: A lesão por inalação de fumaça ou produtos químicos se associa com morbidade e mortalidade. As consequências da inalação resultam de uma resposta inflamatória. A proteína 1 relacionada à uteroglobulina é anti-inflamatória e pode melhorar a inflamação pulmonar. Nossa hipótese é que os níveis de proteína 1 relacionada à uteroglobulina podem refletir a gravidade da doença e predizer o desfecho em pacientes com lesão por inalação. Incluíram-se prospectivamente neste estudo 16 pacientes com diagnóstico de síndrome do desconforto respiratório agudo decorrente de lesão por inalação de fumaça. Em todos os pacientes, colheu-se amostra de plasma quando da admissão à unidade de terapia intensiva, para avaliar a gravidade da lesão por inalação dentro de 72 horas. Os níveis plasmáticos de proteína 1 relacionada à uteroglobulina foram determinados em duplicata por meio de ensaio de imunoabsorção ligado à enzima. Resultados: A média de idade foi de 23 ± 5 anos, e a distribuição da lesão por inalação foi: três em grau 1, quatro em grau 2 e nove em grau 3. O nível de proteína 1 relacionada à uteroglobulina foi relacionado ao grau de severidade (grau 1: 0,389 ± 0,053 unidade arbitrária versus grau 2: 0,474 ± 0,0423 unidade arbitrária versus grau 3: 0,580 ± 0,094 unidade arbitrária; p = 0,007). Conclusão: Os níveis plasmáticos de proteína 1 relacionada à uteroglobulina se associam com o grau da lesão pulmonar por inalação.

ABSTRACT Objective: To evaluate serum uteroglobin-related protein 1 expression early after smoke inhalation injuries and its association with the severity of inhalation injury in burned patients. Methods: Smoke or chemical inhalation injury is associated with morbidity and mortality. The consequences of inhalation result from an inflammatory response. Uteroglobin-related protein 1 is an anti-inflammatory protein and may improve lung inflammation. We hypothesized that uteroglobin-related protein 1 levels could reflect disease severity and predict outcome in patients with inhalation injury. Sixteen patients diagnosed with acute respiratory distress syndrome secondary to smoke inhalation injury were prospectively included in the study. Plasma was collected upon intensive care unit admission and within 24 hours of the inhalation injury. Bronchoscopies were carried out in all patients to assess the severity of inhalation injury within 72 hours. Uteroglobin-related protein 1 plasma levels were determined in duplicate with enzyme-linked immunosorbent assay. Results: The mean age was 23 ± 5 years, and the inhalation injury distribution was as follows: three of grade 1, four of grade 2, and nine of grade 3. The level of uteroglobin-related protein 1 was related to inhalation severity (grade 1: 0.389 ± 0.053 arbitrary units versus grade 2: 0.474 ± 0.0423 arbitrary units versus grade 3: 0.580 ± 0.094 arbitrary units; p = 0.007). Conclusion: Plasma levels of uteroglobin-related protein 1 are associated with the degree of lung inhalation injury.

What Animal Models Can Tell Us About Long-Term Psychiatric Symptoms in Sepsis Survivors: a Systematic Review.

Lower sepsis mortality rates imply that more patients are discharged from the hospital, but sepsis survivors often experience sequelae, such as functional disability, cognitive impairment, and psychiatric morbidity. Nevertheless, the mechanisms underlying these long-term disabilities are not fully understood. Considering the extensive use of animal models in the study of the pathogenesis of neuropsychiatric disorders, it seems adopting this approach to improve our knowledge of postseptic psychiatric symptoms is a logical approach. With the purpose of gathering and summarizing the main findings of studies using animal models of sepsis-induced psychiatric symptoms, we performed a systematic review of the literature on this topic. Thus, 140 references were reviewed, and most of the published studies suggested a time-dependent recovery from behavior alterations, despite the fact that some molecular alterations persist in the brain. This review reveals that animal models can be used to understand the mechanisms that underlie anxiety and depression in animals recovering from sepsis.

What animal models can tell us about long-term cognitive dysfunction following sepsis: A systematic review.

Survivors of sepsis often develop long-term cognitive impairments. This review aimed at exploring the results of the behavioral tools and tests which have been used to evaluate cognitive dysfunction in different animal models of sepsis. Two independent investigators searched for sepsis- and cognition-related keywords. 6323 publications were found, of which 355 were selected based on their title, and 226 of these were chosen based on manuscript review. LPS was used to induce sepsis in 171 studies, while CLP was used in 55 studies. Inhibitory avoidance was the most widely used method for assessing aversive memory, followed by fear conditioning and continuous multi-trial inhibitory avoidance. With regard to non-aversive memory, most studies used the water maze, open-field, object recognition, Y-maze, plus maze, and radial maze tests. Both CLP and LPS models of sepsis were effective in inducing short- and long-term behavioral impairment. Our findings help elucidate the mechanisms involved in the pathophysiology of sepsis-induced cognitive changes, as well as the available methods and tests used to study this in animal models.

Effects of S100B neutralization on the long-term cognitive impairment and neuroinflammatory response in an animal model of sepsis.

The nervous system is one of the first systems to be affected during sepsis. Sepsis not only has a high risk of mortality, but could also lead to cerebral dysfunction and cognitive impairment in long-term survival patients. The receptor for advanced glycation end products (RAGE) can interact with several ligands, and its activation triggers a series of cell signaling events, resulting in the hyperinflammatory condition related to sepsis. Recent studies show that elevated levels of S100B (RAGE ligand) are associated with the pathophysiology of neurodegenerative disorders. They also participate in inflammatory brain diseases and may lead to an increased activation of microglia and astrocytes, leading to neuronal death. This study aimed to determine the effect of S100B inhibition on the neuroinflammatory response in sepsis. Sepsis was induced in Wistar rats by cecal ligation and perforation (CLP). There were three groups: Sham, CLP, and CLP +10 µg/kg of monoclonal antibody (Anti-S100B) administered intracerebroventricularly. The animals were killed 30 days after sepsis following behavioral evaluation by open field, novel object recognition, and splash test. The hippocampus, prefrontal cortex, and amydgala were used for the determination of S100B and RAGE proteins by western blotting and for the evaluation of cytokine levels and verification of the number of microglial cells by immunohistochemistry. On day 30, both the Sham and CLP + anti-S100B groups were capable of recovering the habitual memory in the open field task. Regarding novel object recognition, Sham and CLP + anti-S100B groups increased the recognition index during the test session in comparison to the training session. There was a significant increase in the time of grooming in CLP + anti-S100B in comparison to the CLP group. There was a modulation of cytokine levels and immunohistochemistry showed that the CLP + anti-S100B group had a decrease in the number of microglial cells only in the hippocampus. These results helped to understand the role of S100B protein in the pathophysiology of sepsis-associated encephalopathy and could be helpful to further experimental studies regarding this subject.

Association of neurogranin with delirium among critically ill patients.

Background: Neurogranin (Ng) concentrates at dendritic spines. In patients with Alzheimer disease Ng levels are elevated. The role of Ng in delirium development has not been assessed, therefore we hypothesized that Ng levels are associated with delirium in critically ill patients. Materials & methods: From 94 critically ill patients, 47 developed delirium and 47 controls were included. Blood was collected during the first 24 h of intensive care unit (ICU) admission, and on the day of delirium diagnoses. Ng and IL-1ß were determined. Results: Ng and IL-1ß levels were higher in the delirium group at ICU admission and on the day of delirium diagnoses. IL-1ß and Ng were independently associated with delirium occurrence. Conclusion: Ng levels are associated with delirium development in ICU patients.

Ammonia exposition during gestation induces neonatal oxidative damage in the brain and long-term cognitive alteration in rats.

Ammonia is involved in the pathogenesis of neurological conditions associated with hyperammonemia, including hepatic encephalopathy. Few is known about the effects of gestational exposition to ammonia in the developing brain, and the possible long-term consequences of such exposure. We aimed to evaluate the effects of ammonia exposure during the gestation and the possible long-term cognitive alterations on pups. Eight female rats were divided into two groups: (1) control (saline solution); (2) ammonia (ammonium acetate, 2,5mmol/Kg). Each rat received a single subcutaneous injection during all gestational period. The brains from 1-day-old rats were obtained to the determination of thiobarbituric acid reactive species (TBARS), protein carbonyl and nitrite/nitrate levels. Some animals were followed 30 days after delivery and were subjected to the step-down inhibitory avoidance task. It was observed a significant increase in protein carbonyl, but not TBARS or nitrite/nitrate levels, in pups exposed to ammonia. Rats exposed to ammonia presented long-term cognitive impairment. Gestational exposition to ammonia induces protein oxidative damage in the neonatal rat brain, and long-term cognitive impairment.

Effects of microbiota transplantation and the role of the vagus nerve in gut-brain axis in animals subjected to chronic mild stress.

INTRODUCTION: Currently, there is a growing emphasis on the study of intestinal signaling as an influencer in the pathophysiology of neuropsychiatric diseases, and the gut-brain axis is recognized as a communication route through endocrine, immune, and neural pathways (vagus nerve). Studies have shown that diets that modify the microbiota can reduce stress-related behavior and hypothalamic-pituitary-adrenal axis activation. Investigators have used fecal microbiota transplantation (FMT) approaches to demonstrate that stress-related microbiota composition plays a causal role in behavioral changes. AIM: We hypothesized that FMT may present immunomodulatory, biochemical, endocrine, cognitive, and behavioral benefits in stress situations and that these changes can be mediated via the vagus nerve. METHODS: Animals were subjected to a chronic mild stress (CMS) protocol. In one experiment, animals were divided into five groups: control, control + FMT, control + FMT + CMS, CMS + saline, and CMS + FMT. The animals received FMT, and behavioral tests were performed; cytokine and carbonyl levels were measured. In a second experiment, animals were submitted to vagotomy and divided into two groups: CMS + FMT and CMS + vagotomy + FMT. RESULTS: Animals submitted to the CMS protocol or that received FMT from stressed animals showed behavioral changes and changes in neuroactive substances (increased IL-6 and TNF-α levels and carbonyl proteins). The FMT of healthy donors improved the analyzed parameters. In addition, vagotomy influenced beneficial FMT results, confirmed by behavioral testing and protein carbonyl in the hippocampus. CONCLUSION: Manipulation of the microbiota reversed the behavioral and biochemical changes induced by the CMS protocol, and the vagus nerve influenced the gut-brain axis response.

Stratification to predict the response to antioxidant. / Estratificação para predizer a resposta ao tratamento antioxidante em terapia intensiva: um estudo translacional.

OBJECTIVE: To examine the effectiveness of stratification to identify and target antioxidant therapy for animal models of lethal sepsis and in patients who develop sustained hypotension. METHODS: Rats were subjected to sepsis induced by cecal ligation and puncture. Animals were divided into two groups: those with high and low plasma levels of interleukin-6. Following stratification, N-acetylcysteine plus deferoxamine or saline was administered to animals starting 3 and 12 hours after surgery. N-Acetylcysteine plus deferoxamine or placebo was administered within 12 hours of meeting the inclusion criteria in hypotensive patients. RESULTS: N-Acetylcysteine plus deferoxamine increased survival in the cecal ligation and puncture model when administered 3 and 12 hours after sepsis induction. When dividing animals that received antioxidants using plasma interleukin-6 levels, the protective effect was observed only in those animals with high IL-6 levels. The antioxidant effect of N-acetylcysteine + deferoxamine was similar in the two groups, but a significant decrease in plasma interleukin-6 levels was observed in the high-interleukin-6-level group. Compared with patients treated with antioxidants in the low-interleukin-6 subgroup, those in the high-interleukin-6 subgroup had a lower incidence of acute kidney injury but were not different in terms of acute kidney injury severity or intensive care unit mortality. CONCLUSION: Targeting antioxidant therapy to a high inflammatory phenotype would select a responsive population.

Mitochondrial dysfunction is associated with long-term cognitive impairment in an animal sepsis model.

Background: Several different mechanisms have been proposed to explain long-term cognitive impairment in sepsis survivors. The role of persisting mitochondrial dysfunction is not known. We thus sought to determine whether stimulation of mitochondrial dynamics improves mitochondrial function and long-term cognitive impairment in an experimental model of sepsis.Methods: Sepsis was induced in adult Wistar rats by cecal ligation and perforation (CLP). Animals received intracerebroventricular injections of either rosiglitazone (biogenesis activator), rilmenidine, rapamycin (autophagy activators), or n-saline (sham control) once a day on days 7-9 after the septic insult. Cognitive impairment was assessed by inhibitory avoidance and object recognition tests. Animals were killed 24 h, 3 and 10 days after sepsis with the hippocampus and prefrontal cortex removed to determine mitochondrial function.Results: Sepsis was associated with both acute (24 h) and late (10 days) brain mitochondrial dysfunction. Markers of mitochondrial biogenesis, autophagy and mitophagy were not up-regulated during these time points. Activation of biogenesis (rosiglitazone) or autophagy (rapamycin and rilmenidine) improved brain ATP levels and ex vivo oxygen consumption and the long-term cognitive impairment observed in sepsis survivors.Conclusion: Long-term impairment of brain function is temporally related to mitochondrial dysfunction. Activators of autophagy and mitochondrial biogenesis could rescue animals from cognitive impairment.