Metabolic theory of septic shock

Unraveling the Multifaceted Role of Glutathione in Sepsis: A Comprehensive Review

Sepsis remains a formidable challenge in healthcare, characterized by a dysregulated host response to infection, leading to organ dysfunction and high mortality rates. Glutathione, a critical antioxidant and regulator of cellular redox balance, has emerged as a key player in the pathophysiology of sepsis. This comprehensive review explores the multifaceted role of glutathione in sepsis, focusing on its involvement in oxidative stress, immune modulation, and organ dysfunction. Glutathione depletion exacerbates oxidative damage and inflammatory responses, thereby contributing to the progression of sepsis. Understanding the intricate mechanisms underlying glutathione dysregulation in sepsis offers potential therapeutic avenues, with strategies targeting glutathione pathways showing promise in mitigating septic complications. However, further research is needed to optimize therapeutic approaches and identify biomarkers for patient stratification. Overall, this review underscores the importance of elucidating glutathione's role in sepsis management to improve clinical outcomes and reduce the global burden of this life-threatening condition.

Kidney function as a key driver of the pharmacokinetic response to high-dose L-carnitine in septic shock

STUDY OBJECTIVE

Levocarnitine (L-carnitine) has shown promise as a metabolic-therapeutic for septic shock, where mortality approaches 40%. However, high-dose (≥ 6 grams) intravenous supplementation results in a broad range of serum concentrations. We sought to describe the population pharmacokinetics (PK) of high-dose L-carnitine, test various estimates of kidney function, and assess the correlation of PK parameters with pre-treatment metabolites in describing drug response for patients with septic shock.

DESIGN

Population PK analysis was done with baseline normalized concentrations using nonlinear mixed effect models in the modeling platform Monolix. Various estimates of kidney function, patient demographics, dose received, and organ dysfunction were tested as population covariates.

DATA SOURCE

We leveraged serum samples and metabolomics data from a phase II trial of L-carnitine in vasopressor-dependent septic shock. Serum was collected at baseline (T0); end-of-infusion (T12); and 24, 48, and 72 h after treatment initiation.

PATIENTS AND INTERVENTION

Patients were adaptively randomized to receive intravenous L-carnitine (6 grams, 12 grams, or 18 grams) or placebo.

MEASUREMENTS AND MAIN RESULTS

The final dataset included 542 serum samples from 130 patients randomized to L-carnitine. A two-compartment model with linear elimination and a fixed volume of distribution (17.1 liters) best described the data and served as a base structural model. Kidney function estimates as a covariate on the elimination rate constant (k) reliably improved model fit. Estimated glomerular filtration rate (eGFR), based on the 2021 Chronic Kidney Disease Epidemiology collaboration (CKD-EPI) equation with creatinine and cystatin C, outperformed creatinine clearance (Cockcroft-Gault) and older CKD-EPI equations that use an adjustment for self-identified race.

CONCLUSIONS

High-dose L-carnitine supplementation is well-described by a two-compartment population PK model in patients with septic shock. Kidney function estimates that leverage cystatin C provided superior model fit. Future investigations into high-dose L-carnitine supplementation should consider baseline metabolic status and dose adjustments based on renal function over a fixed or weight-based dosing paradigm.

U-shaped association between serum triglyceride levels and mortality among septic patients: An analysis based on the MIMIC-IV database

BACKGROUND

Sepsis is characterized by upregulated lipolysis in adipose tissue and a high blood triglyceride (TG) level. It is still debated whether serum TG level is related to mortality in septic patients. The aim of this study is to investigate the association between serum TG level and mortality in septic patients admitted to the intensive care unit (ICU).

METHODS

Data from adult septic patients (≥18 years) admitted to the ICU for the first time were obtained from the Multiparameter Intelligent Monitoring in Intensive Care IV (MIMIC-IV) database. The patients' serum TG levels that were measured within the first week after ICU admission were extracted for statistical analysis. The endpoints were 28-day, ICU and in-hospital mortality.

RESULTS

A total of 2,782 septic patients were included. Univariate analysis indicated that the relationship between serum TG levels and the risk of mortality was significantly nonlinear. Both the Lowess smoothing technique and restricted cubic spline analyses revealed a U-shaped association between serum TG levels and mortality among septic patients. The lowest mortality rate was associated with a serum TG level of 300-500 mg/dL. Using 300∼500 mg/dL as the reference range, we found that both hypo-TG (<300 mg/dL) and hyper-TG (≥500 mg/dL) were associated with increased mortality. The result was further adjusted by Cox regression with and without the inclusion of some differential covariates.

CONCLUSIONS

There was a U-shaped association between serum TG and mortality in septic ICU patients. The optimal concentration of serum TG levels in septic ICU patients is 300-500 mg/dL.

CD3D and CD247 are the molecular targets of septic shock

Septic shock is a serious systemic disease with circulatory failure and abnormal cell metabolism caused by sepsis. However, the relationship between CD3D and CD247 and septic shock remains unclear. The septic shock datasets GSE33118 and GSE142255 profiles were generated from the gene expression omnibus databases GPl570, GPl17586. Differentially expressed genes (DEGs) were screened and weighted gene co-expression network analysis was performed. The construction and analysis of protein-protein interaction (PPI) network, functional enrichment analysis, gene set enrichment analysis (GSEA) were performed. Gene expression heat map was drawn. Immune infiltration analysis was performed. Comparative toxicogenomics database (CTD) analysis were performed to find the disease most related to the core gene. Targets can was used to screen miRNAs regulating the hub DEGs. 467 DEGs were identified. According to the gene ontology analysis, they were mainly enriched in the regulation of immune response, cell activation, signaling receptor activity, enzyme binding. Kyoto encyclopedia of genes and genomes analysis showed that they were mainly enriched in the TCR signaling pathway, Fc epsilon RI signaling pathway. GSEA showed that the DEGs were mainly enriched in immune response regulation, cell activation, TCR signaling pathway, Fc epsilon RI signaling pathway. Positive regulation of Fc receptor signaling pathway, PID IL12 2 pathway, immune response was observed in go enrichment items in the enrichment items of metascape. PPI networks got 5 core genes. Gene expression heat map showed that 5 core genes (CD247, Lck, cd3e, cd3d, ITK) were lowly expressed in the sepsis shock samples and highly expressed in the normal samples. CTD analysis showed that 5 core genes (CD247, Lck, cd3e, cd3d, ITK) were found to be associated with hemorrhage and necrosis. Low expression of cd3d, CD247 was observed in septic shock, and the lower the level of cd3d, CD247, the worse the prognosis.

Proteomic Approaches to Unravel Mechanisms of Antibiotic Resistance and Immune Evasion of Bacterial Pathogens

The profound effects of and distress caused by the global COVID-19 pandemic highlighted what has been known in the health sciences a long time ago: that bacteria, fungi, viruses, and parasites continue to present a major threat to human health. Infectious diseases remain the leading cause of death worldwide, with antibiotic resistance increasing exponentially due to a lack of new treatments. In addition to this, many pathogens share the common trait of having the ability to modulate, and escape from, the host immune response. The challenge in medical microbiology is to develop and apply new experimental approaches that allow for the identification of both the microbe and its drug susceptibility profile in a time-sensitive manner, as well as to elucidate their molecular mechanisms of survival and immunomodulation. Over the last three decades, proteomics has contributed to a better understanding of the underlying molecular mechanisms responsible for microbial drug resistance and pathogenicity. Proteomics has gained new momentum as a result of recent advances in mass spectrometry. Indeed, mass spectrometry-based biomedical research has been made possible thanks to technological advances in instrumentation capability and the continuous improvement of sample processing and workflows. For example, high-throughput applications such as SWATH or Trapped ion mobility enable the identification of thousands of proteins in a matter of minutes. This type of rapid, in-depth analysis, combined with other advanced, supportive applications such as data processing and artificial intelligence, presents a unique opportunity to translate knowledge-based findings into measurable impacts like new antimicrobial biomarkers and drug targets. In relation to the Research Topic “Proteomic Approaches to Unravel Mechanisms of Resistance and Immune Evasion of Bacterial Pathogens,” this review specifically seeks to highlight the synergies between the powerful fields of modern proteomics and microbiology, as well as bridging translational opportunities from biomedical research to clinical practice.

Urine Hydrogen Peroxide Levels and Their Relation to Outcome in Patients with Sepsis, Septic Shock, and Major Burn Injury

Hydrogen peroxide (H2O2) and oxidative stress have been suggested as possible instigators of both the systemic inflammatory response and the increased vascular permeability associated with sepsis and septic shock. We measured H2O2 concentrations in the urine of 82 patients with severe infections, such as sepsis, septic shock, and infections not fulfilling sepsis-3 criteria, in patients with major burn injury with associated systemic inflammation, and healthy subjects. The mean concentrations of H2O2 were found to be lower in patients with severe infections compared to burn injury patients and healthy subjects. Patients with acute kidney injury (AKI), vs. those without AKI, in all diagnostic groups displayed higher concentrations of urine H2O2 (p < 0.001). Likewise, urine concentrations of H2O2 were higher in non-survivors as compared to survivors (p < 0.001) at day 28 in all diagnostic groups, as well as in patients with severe infections and burn injury (p < 0.001 for both). In this cohort, increased H2O2 in urine is thus associated with mortality in patients with sepsis and septic shock as well as in patients with burn injury.

Oxygen therapy for sepsis and prevention of complications

Patients with sepsis have a wide range of respiratory disorders that can be treated with oxygen therapy. Experimental data in animal sepsis models show that oxygen therapy significantly increases survival, while clinical data on the use of different oxygen therapy protocols are ambiguous. Oxygen therapy, especially hyperbaric oxygenation, in patients with sepsis can aggravate existing oxidative stress and contribute to the development of disseminated intravascular coagulation. The purpose of this article is to compare experimental and clinical data on oxygen therapy in animals and humans, to discuss factors that can influence the results of oxygen therapy for sepsis treatment in humans, and to provide some recommendations for reducing oxidative stress and preventing disseminated intravascular coagulation during oxygen therapy.

Assessment of Metabolic Dysfunction in Sepsis in a Retrospective Single-Centre Cohort

Objective

Our primary aim was to assess selected metabolic dysfunction parameters, both independently and as a complement to the SOFA score, as predictors of short-term mortality in patients with infection admitted to the intensive care unit (ICU).

Methods

We retrospectively enrolled all consecutive adult patients admitted to the eight ICUs of Lille University Hospital, between January 2015 and September 2016, with suspected or confirmed infection. We selected seven routinely measured biological and clinical parameters of metabolic dysfunction (maximal arterial lactatemia, minimal and maximal temperature, minimal and maximal glycaemia, cholesterolemia, and triglyceridemia), in addition to age and the Charlson's comorbidity score. All parameters and SOFA scores were recorded within 24 h of admission.

Results

We included 956 patients with infection, among which 295 (30.9%) died within 90 days. Among the seven metabolic parameters investigated, only maximal lactatemia was associated with higher risk of 90-day hospital mortality in SOFA-adjusted analyses (SOFA-adjusted OR, 1.17; 95%CI, 1.10 to 1.25; p < 0.001). Age and the Charlson's comorbidity score were also statistically associated with a poor prognosis in SOFA-adjusted analyses. We were thus able to develop a metabolic failure, age, and comorbidity assessment (MACA) score based on scales of lactatemia, age, and the Charlson's score, intended for use in combination with the SOFA score.

Conclusions

The maximal lactatemia level within 24 h of ICU admission is the best predictor of short-term mortality among seven measures of metabolic dysfunction. Our combined "SOFA + MACA" score could facilitate early detection of patients likely to develop severe infections. Its accuracy requires further evaluation.

A Metabolomics approach for the diagnosis Of SecondAry InfeCtions in COVID-19 (MOSAIC): a study protocol

Background

Critically ill patients with COVID-19 are at an increased risk of developing secondary bacterial infections. These are both difficult to diagnose and are associated with an increased mortality. Metabolomics may aid clinicians in diagnosing secondary bacterial infections in COVID-19 through identification and quantification of disease specific biomarkers, with the aim of identifying underlying causative microorganisms and directing antimicrobial therapy.

Methods

This is a multi-centre prospective diagnostic observational study. Patients with COVID-19 will be recruited from critical care units in three Scottish hospitals. Three serial blood samples will be taken from patients, and an additional sample taken if a patient shows clinical or microbiological evidence of secondary infection. Samples will be analysed using LC–MS and subjected to bioinformatic processing and statistical analysis to explore the metabolite changes associated with bacterial infections in COVID-19 patients. Comparisons of the data sets will be made with standard microbiological and biochemical methods of diagnosing infection.

Discussion

Metabolomics analyses may provide additional strategies for identifying secondary infections, which might permit faster initiation of specific tailored antimicrobial therapy to critically ill patients with COVID-19.

In vitro and in vivo comparison of eravacycline- and tigecycline-based combination therapies for tigecycline-resistant Acinetobacter baumannii

Several antimicrobial combination therapies are used to treat multiple drug resistant (MDR) and extensively drug resistant (XDR) Acinetobacter baumannii infections. A novel antibiotic, eravacycline, shows a higher potency than tigecycline. The efficacies of eravacycline-based therapies have not yet been evaluated. We demonstrated the effectiveness of eravacycline- and tigecycline-based combination therapies in XDR and especially tigecycline resistant A. baumannii. Thirteen eligible isolates were selected from 642 non-duplicate Acinetobacter blood isolates from four medical centres in 2010-2014. Tigecycline/imipenem and eravacycline/imipenem combinations were simultaneously effective against some isolates in vitro with fractional inhibitory concentration index of 0.5. In contrast, eravacycline- and tigecycline-based combination therapies provided no additional benefits in mouse survival compared to those for monotherapy. In summary, colistin is still the final resort for XDR-A. baumannii treatment according to the sensitivities. Owning to rapid development of resistance in A. baumannii, novel antibiotics are urgently needed.

Sepsis: Evidence-based pathogenesis and treatment

Sepsis can develop during the body’s response to a critical illness leading to multiple organ failure, irreversible shock, and death. Sepsis has been vexing health care providers for centuries due to its insidious onset, generalized metabolic dysfunction, and lack of specific therapy. A common factor underlying sepsis is the characteristic hypermetabolic response as the body ramps up every physiological system in its fight against the underlying critical illness. A hypermetabolic response requires supraphysiological amounts of energy, which is mostly supplied via oxidative phosphorylation generated ATP. A by-product of oxidative phosphorylation is hydrogen peroxide (H₂O₂), a toxic, membrane-permeable oxidizing agent that is produced in far greater amounts during a hypermetabolic state. Continued production of mitochondrial H₂O₂ can overwhelm cellular reductive (antioxidant) capacity leading to a build-up within cells and eventual diffusion into the bloodstream. H₂O₂ is a metabolic poison that can inhibit enzyme systems leading to organ failure, microangiopathic dysfunction, and irreversible septic shock. The toxic effects of H₂O₂ mirror the clinical and laboratory abnormalities observed in sepsis, and toxic levels of blood H₂O₂ have been reported in patients with septic shock. This review provides evidence to support a causal role for H₂O₂ in the pathogenesis of sepsis, and an evidence-based therapeutic intervention to reduce H₂O₂ levels in the body and restore redox homeostasis, which is necessary for normal organ function and vascular responsiveness.

Echinochrome pigment extracted from sea urchin suppress the bacterial activity, inflammation, nociception, and oxidative stress resulted in the inhibition of renal injury in septic rats

The current study aimed to evaluate the antibacterial, anti-inflammatory, analgesic, and renoprotective effects of echinochrome pigment extracted from sea urchin. The disk diffusion method was used for the antibacterial activity of echinochrome against four different bacterial strains; Salmonella typhimurium, Pseudomonas aeroginosa, Staphylococcus aureus, and Listeria monocytogenes. While, acetic acid-induced writhing, formalin-induced licking, and hot plate latency assays evaluate the analgesic activity. The biochemical and oxidative stress markers of kidneys, as well as the histopathological examination, were measured to evaluate the renoprotective activity of echinochrome for cecal ligation and puncture-induced renal injury in rats. Echinochrome pigment exhibited in vitro antibacterial activity against all aforementioned bacterial species besides a powerful anti-inflammatory impact in vitro by the effective stabilization of the RBCs membrane and in vivo by decrease levels of serum IL6 and TNF-α. What's more, echinochrome showed a notable analgesic efficacy as well as an enhancement of the kidney's biochemical markers, oxidative stress status, and histopathological screening. Ech attenuated cecal ligation and puncture-induced renal injury by improving renal biomarkers, suppressing reactive oxygen species propagation as well as its antibacterial, anti-inflammatory, and anti-nociceptive activities. PRACTICAL APPLICATIONS: Sea urchins are rich in pharmacologically important quinone pigments, specifically echinochrome. The current study aimed to evaluate the role of echinochrome as a renal protective remedy in sepsis and clarify its biological activities. Echinochrome exhibited antibacterial activity in vitro against Salmonella typhimurium, Pseudomonas aeroginosa, Staphylococcus aureus, and Listeria monocytogenes. Our results revealed that echinochrome protects the kidney against damage caused by sepsis in rats. Echinochrome can use in the treatment of sepsis as an antibacterial, anti-inflammatory, and antioxidant agent.

The diversity and coexistence of extracellular mitochondria in circulation: A friend or foe of the immune system

The diversity and coexistence of extracellular mitochondria may have a key role in the maintenance of health and progression of disease. Studies report that active mitochondria can be found physiologically outside of cells and circulating in the blood without inducing an inflammatory response. In addition, inactive or harmed mitochondria have been recognized as activators of immune cells, as they play an essential role in diseases characterized by the metabolic deregulation of these cells, such as sepsis. In this review we analyze key aspects regarding the existence of a diversity of extracellular mitochondria, their coexistence in body fluids and their effects on various immune cells. Additionally, we introduce models of how extracellular mitochondria could be interacting to maintain health and affect disease prognosis. Unwrapped mitochondria (freeMitos) can exist as viable, active, inactive or harmed organelles. Mitochondria can also be found wrapped in a membrane (wrappedMitos) that may differ depending on the cell of origin. Mitochondrial fragments can also be present in various body fluids as DAMPs, as mtDNA enclosed in vesicles or as circulating-cell-free mtDNA (ccf-mtDNA). Interestingly, the great quantity of evidence regarding the levels of ccf-mtDNA and their correlation with aging and disease allows for the identification of the diversity, but not type, of extracellular mitochondria. The existence of a diversity of mitochondria and their effects on immune cells opens a new concept in the biomedical field towards the understanding of health, the progression of disease and the development of mitochondria as therapeutic agents.

Effect of Hyperbaric Oxygen Therapy on Acute Liver Injury and Survival in a Rat Cecal Slurry Peritonitis Model

BACKGROUND

The effects of hyperbaric oxygen therapy (HBOT) in sepsis remain unclear. This study evaluated its effects on acute liver injury and survival in a rat model.

METHODS

Cecal slurry peritonitis was induced in male rats, which were then randomly allocated into the HBOT and control groups. In the survival experiment, six 90 min HBOT sessions (2.6 atmospheres absolute 100% oxygen) were performed over 48 h; the survival rate was determined 14 days after sepsis induction. In the acute liver injury experiment, three HBOT sessions were performed, followed by liver and plasma harvesting, 24 h after sepsis induction. Serum levels of alanine aminotransferase (ALT), interleukin (IL)-6, and IL-10 were measured, and the hepatic injury scores were determined. Reactive oxygen species (ROS) generation was detected by 2',7'-dihydrodichlorofluorescein diacetate (H2DCF-DA) assay. Western blot assays assessed protein kinase B (Akt), phosphorylated-Akt (p-Akt), glycogen synthase kinase (GSK)-3β, phosphorylated-GSK-3β, and cleaved caspase-3 levels.

RESULTS

Survival in the HBOT group (57.1%) was significantly higher than that in the controls (12.5%, p = 0.029), whereas IL-6, IL-10, and ALT levels were significantly lower in the HBOT group. The ROS generation was significantly inhibited to a greater extent in the HBOT group than in the control group. Additionally, in the HBOT group, the p-Akt and p-GSK-3β increased significantly and cleaved caspase-3 levels decreased significantly.

CONCLUSIONS

HBOT showed a beneficial effect on acute liver injury and rat survival by enhancing the Akt signaling pathway and decreasing apoptosis.

Down regulation of glutathione and glutamate cysteine ligase in the inflammatory response of macrophages

Glutathione (GSH) plays critical roles in the inflammatory response by acting as the master substrate for antioxidant enzymes and an important anti-inflammatory agent. In the early phase of the inflammatory response of macrophages, GSH content is decreased due to the down regulation of the catalytic subunit of glutamate cysteine ligase (GCLC). In the current study we investigated the underlying mechanism for this phenomenon. In human THP1-differentiated macrophages, GCLC mRNA had a half-life of 4 h under basal conditions, and it was significantly reduced to less than 2 h upon exposure to lipopolysaccharide (LPS), suggesting an increased decay of GCLC mRNA in the inflammatory response. The half-life of GCLC protein was >10 h under basal conditions, and upon LPS exposure the degradation rate of GCLC protein was significantly increased. The pan-caspase inhibitor Z-VAD-FMK but not the proteasome inhibitor MG132, prevented the down regulation of GCLC protein caused by LPS. Both caspase inhibitor Z-LEVD-FMK and siRNA of caspase-5 abrogated LPS-induced degradation of GCLC protein. In addition, supplement with γ-GC, the GCLC product, efficiently restored GSH content and suppressed the induction of NF-κB activity by LPS. In conclusion, these data suggest that GCLC down-regulation in the inflammatory response of macrophages is mediated through both increased mRNA decay and caspase-5-mediated GCLC protein degradation, and γ-GC is an efficient agent to restore GSH and regulate the inflammatory response.

Using l-Carnitine as a Pharmacologic Probe of the Interpatient and Metabolic Variability of Sepsis

OBJECTIVE

The objective of this review is to discuss the therapeutic use and differential treatment response to Levo-carnitine (l-carnitine) treatment in septic shock, and to demonstrate common lessons learned that are important to the advancement of precision medicine approaches to sepsis. We propose that significant interpatient variability in the metabolic response to l-carnitine and clinical outcomes can be used to elucidate the mechanistic underpinnings that contribute to sepsis heterogeneity.

METHODS

A narrative review was conducted that focused on explaining interpatient variability in l-carnitine treatment response. Relevant biological and patient-level characteristics considered include genetic, metabolic, and morphomic phenotypes; potential drug interactions; and pharmacokinetics (PKs).

MAIN RESULTS

Despite promising results in a phase I study, a recent phase II clinical trial of l-carnitine treatment in septic shock showed a nonsignificant reduction in mortality. However, l-carnitine treatment induces significant interpatient variability in l-carnitine and acylcarnitine concentrations over time. In particular, administration of l-carnitine induces a broad, dynamic range of serum concentrations and measured peak concentrations are associated with mortality. Applied systems pharmacology may explain variability in drug responsiveness by using patient characteristics to identify pretreatment phenotypes most likely to derive benefit from l-carnitine. Moreover, provocation of sepsis metabolism with l-carnitine offers a unique opportunity to identify metabolic response signatures associated with patient outcomes. These approaches can unmask latent metabolic pathways deranged in the sepsis syndrome and offer insight into the pathophysiology, progression, and heterogeneity of the disease.

CONCLUSIONS

The compiled evidence suggests there are several potential explanations for the variability in carnitine concentrations and clinical response to l-carnitine in septic shock. These serve as important confounders that should be considered in interpretation of l-carnitine clinical studies and broadly holds lessons for future clinical trial design in sepsis. Consideration of these factors is needed if precision medicine in sepsis is to be achieved.

An Ultrasmall RuO2 Nanozyme Exhibiting Multienzyme-like Activity for the Prevention of Acute Kidney Injury

Oxidative stress induced by reactive oxygen species (ROS) is one of the major pathological mechanisms of acute kidney injury (AKI). Inorganic nanomaterial-mediated antioxidant therapy is considered a promising method for the prevention of AKI; however, currently available antioxidants for AKI exhibit limited clinical efficacy due to the glomerular filtration threshold (∼6 nm). To address this issue, we developed ultrasmall RuO₂ nanoparticles (RuO₂NPs) (average size ≈ 2 nm). The NPs show excellent antioxidant activity and low biological toxicity. In addition, they can pass through the glomerulus to be excreted. These properties in combination make the ultrasmall RuO₂NPs promising as a nanozyme for the prevention of AKI. The NP catalytic properties mimic the activity of catalase, peroxidase, superoxide dismutase, and glutathione peroxidase. The nanozyme can be efficiently and rapidly absorbed by human embryonic kidney cells while significantly reducing ROS-induced apoptosis by eliminating excess ROS. After intravenous injection, the ultrasmall RuO₂NPs significantly inhibit the development of AKI in mice. In vivo toxicity experiments demonstrate the biosafety of the NPs after long-term preventing. The multienzyme-like activity and biocompatibility of the ultrasmall RuO₂NPs makes them of great interest for applications in the fields of biomedicine and biocatalysis.

Hydrogen peroxide and disease: towards a unified system of pathogenesis and therapeutics

Although the immune response has a prominent role in the pathophysiology of ulcerative colitis, sepsis, and systemic lupus erythematosus, a primary immune causation has not been established to explain the pathogenesis of these diseases. However, studies have reported significantly elevated levels of colonic epithelial hydrogen peroxide (a known colitic agent) in ulcerative colitis prior to the appearance of colitis. And patients with sepsis are reported to have toxic levels of blood hydrogen peroxide, whose pathologic effects mirror the laboratory and clinical abnormalities observed in sepsis. More recently, evidence supports a causal role for cellular hydrogen peroxide (a potent apoptotic agent) in the enhanced apoptosis believed to be the driving force behind auto-antigenic exposure and chronic immune activation in systemic lupus erythematosus. The different biological properties of hydrogen peroxide exert distinct pathologic effects depending on the site of accumulation within the body resulting in a unique disease patho-phenotype. On a cellular level, the build-up of hydrogen peroxide triggers apoptosis resulting in systemic lupus erythematosus, on a tissue level (colonic epithelium) excess hydrogen peroxide leads to inflammation and ulcerative colitis, and on a systemic level the pathologic effects of toxic concentrations of blood hydrogen peroxide result in bioenergetic failure and microangiopathic dysfunction leading to multiple organ failure and circulatory shock, characteristic of advanced sepsis. The aim of this paper is to provide a unified evidence-based common causal role for hydrogen peroxide in the pathogenesis of ulcerative colitis, sepsis, and systemic lupus erythematosus. Based on this new theory of pathogenesis, a novel evidence-based treatment of sepsis is also discussed.

Enteral vs. parenteral nutrition in septic shock: are they equivalent?

PURPOSE OF REVIEW

The current review focuses on recent clinical evidence and updated guideline recommendations on the effects of enteral vs. parenteral nutrition in adult critically ill patients with (septic) shock.

RECENT FINDIGS

The largest multicenter randomized-controlled trial showed that the route of nutrient supply was unimportant for 28-day and 90-day mortality, infectious morbidity and length of stay in mechanically ventilated patients with shock. The enteral route, however, was associated with lower macronutrient intake and significantly higher frequency of hypoglycemia and moderate-to-severe gastrointestinal complications. Integrating these findings into recent meta-analyses confirmed that the route per se has no effect on mortality and that interactions with (infectious) morbidity are inconsistent or questionable.

SUMMARY

The strong paradigm of favoring the enteral over the parenteral route in critically ill patients has been challenged. As a consequence, updated guidelines recommend withholding enteral nutrition in patients with uncontrolled shock. It is still unclear, however, whether parenteral nutrition is advantageous in patients with shock although benefits are conceivable in light of less gastrointestinal complications. Thus far, no guideline has addressed indications for parenteral nutrition in these patients. By considering recent scientific evidence, specific guideline recommendations, and expert opinions, we present a clinical algorithm that may facilitate decision-making when feeding critically ill patients with shock.

Analysis of Spatiotemporal Urine Protein Dynamics to Identify New Biomarkers for Sepsis-Induced Acute Kidney Injury

Acute kidney injury (AKI) is a frequent complication of sepsis and contributes to increased mortality. Discovery of reliable biomarkers could enable identification of individuals with high AKI risk as well as early AKI detection and AKI progression monitoring. However, the current methods are insensitive and non-specific. This study aimed to identify new biomarkers through label-free mass spectrometry (MS) analysis of a sepsis model induced by cecal ligation and puncture (CLP). Urine samples were collected from septic rats at 0, 3, 6, 12, 24, and 48 h. Protein isolated from urine was subjected to MS. Immunoregulatory biological processes, including immunoglobin production and wounding and defense responses, were upregulated at early time points. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses identified 77 significantly changed pathways. We further examined the consistently differentially expressed proteins to seek biomarkers that can be used for early diagnosis. Notably, the expression of PARK7 and CDH16 were changed in a continuous manner and related to the level of Scr in urine from patients. Therefore, PARK7 and CDH16 were confirmed to be novel biomarkers after validation in sepsis human patients. In summary, our study analyzed the proteomics of AKI at multiple time points, elucidated the related biological processes, and identified novel biomarkers for early diagnosis of sepsis-induced AKI, and our findings provide a theoretical basis for further research on the molecular mechanisms.

Toll-like Receptor 4-Independent Effects of Lipopolysaccharide Identified Using Longitudinal Serum Proteomics

Sepsis remains one of the most lethal and costly conditions treated in U.S. hospitals, with approximately 50% of cases caused by Gram-negative bacterial infections. Septic shock is induced when lipopolysaccharide (LPS), the main component of Gram-negative outer bacterial membrane, signals through the Toll-like receptor 4 (TLR4) complex. Lethal endotoxemia, a model for septic shock, was induced in WT C57BL6 and TLR4^-/- mice by administration of Escherichia coli LPS. WT LPS treated mice showed high morbidity, while PBS treated LPS and treated TLR4^-/- mice did not. ANOVA analysis of label-free quantification of longitudinal serum proteome revealed 182 out of 324 proteins in LPS injected WT mice that were significantly changed across four time points (0, 6, 12, and 18 h). No significant changes were identified in the two control groups. From the 182 identified proteins, examples of known sepsis biomarkers were validated by ELISA, which showed similar trends as MS proteomics data. Longitudinal analysis within individual mice produced 3-fold more significantly changed proteins than pair-wise comparison. A subsequent global analysis of WT and TLR4^-/- mice identified pathways activated independent of TLR4. These pathways represent possible compensatory mechanisms that allow for control of Gram-negative bacterial infection regardless of host immune status.

Cellular Stress and General Pathological Processes

From the viewpoint of the general pathology, most of the human diseases are associated with a limited number of pathogenic processes such as inflammation, tumor growth, thrombosis, necrosis, fibrosis, atrophy, pathological hypertrophy, dysplasia and metaplasia. The phenomenon of chronic low-grade inflammation could be attributed to non-classical forms of inflammation, which include many neurodegenerative processes, pathological variants of insulin resistance, atherosclerosis, and other manifestations of the endothelial dysfunction. Individual and universal manifestations of cellular stress could be considered as a basic element of all these pathologies, which has both physiological and pathophysiological significance. The review examines the causes, main phenomena, developmental directions and outcomes of cellular stress using a phylogenetically conservative set of genes and their activation pathways, as well as tissue stress and its role in inflammatory and para-inflammatory processes. The main ways towards the realization of cellular stress and its functional blocks were outlined. The main stages of tissue stress and the classification of its typical manifestations, as well as its participation in the development of the classical and non-classical variants of the inflammatory process, were also described. The mechanisms of cellular and tissue stress are structured into the complex systems, which include networks that enable the exchange of information with multidirectional signaling pathways which together make these systems internally contradictory, and the result of their effects is often unpredictable. However, the possible solutions require new theoretical and methodological approaches, one of which includes the transition to integral criteria, which plausibly reflect the holistic image of these processes.

Cannabis Sativa Revisited-Crosstalk between microRNA Expression, Inflammation, Oxidative Stress, and Endocannabinoid Response System in Critically Ill Patients with Sepsis

Critically ill patients with sepsis require a multidisciplinary approach, as this situation implies multiorgan distress, with most of the bodily biochemical and cellular systems being affected by the condition. Moreover, sepsis is characterized by a multitude of biochemical interactions and by dynamic changes of the immune system. At the moment, there is a gap in our understanding of the cellular, genetic, and molecular mechanisms involved in sepsis. One of the systems intensely studied in recent years is the endocannabinoid signaling pathway, as light was shed over a series of important interactions of cannabinoid receptors with biochemical pathways, specifically for sepsis. Furthermore, a series of important implications on inflammation and the immune system that are induced by the activity of cannabinoid receptors stimulated by the delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) have been noticed. One of the most important is their ability to reduce the biosynthesis of pro-inflammatory mediators and the modulation of immune mechanisms. Different studies have reported that cannabinoids can reduce oxidative stress at mitochondrial and cellular levels. The aim of this review paper was to present, in detail, the important mechanisms modulated by the endocannabinoid signaling pathway, as well as of the molecular and cellular links it has with sepsis. At the same time, we wish to present the possible implications of cannabinoids in the most important biological pathways involved in sepsis, such as inflammation, redox activity, immune system, and epigenetic expression.

Predictive value of combined serum FGF21 and free T3 for survival in septic patients

BACKGROUND

We examined the correlation between thyroid hormone (TH) concentrations and the serum fibroblast growth factor 21 (FGF21) concentration in septic patients and to assess the collaborative value of these factors in predicting 28-day mortality in septic patients.

METHODS

A total of 120 consecutive patients with sepsis were divided into two groups according to their survival or death within 28 days after initial diagnosis of sepsis.

RESULTS

Patients in the non-survivor group had significantly higher serum FGF21 concentrations but lower total and free triiodothyronine (T3) and tetraiodothyronine (T4) concentrations than those in the survivor group. Thyroid hormone concentrations, including T3, free T3, T4 and free T4, were significantly negatively correlated with the ∆SOFA and APACHE II scores as well as the serum FGF21, IL-6, tumor necrosis factor-α, IL-10, procalcitonin, and C-reactive protein concentrations. Logistic regression analysis showed that the ∆SOFA score, serum FGF21 concentration, and free T3 concentration were significant predictors of 28-day mortality. The model with variables of ∆SOFA score and serum FGF21 and free T3 concentrations had the greatest area under the curve of 0.969.

CONCLUSION

The addition of free T3 and serum FGF21 to ∆SOFA score provided a significantly improved ability to predict 28-day mortality in septic patients.

Autophagy in Adipocyte Browning: Emerging Drug Target for Intervention in Obesity

Autophagy, lipophagy, and mitophagy are considered to be the major recycling processes for protein aggregates, excess fat, and damaged mitochondria in adipose tissues in response to nutrient status-associated stress, oxidative stress, and genotoxic stress in the human body. Obesity with increased body weight is often associated with white adipose tissue (WAT) hypertrophy and hyperplasia and/or beige/brown adipose tissue atrophy and aplasia, which significantly contribute to the imbalance in lipid metabolism, adipocytokine secretion, free fatty acid release, and mitochondria function. In recent studies, hyperactive autophagy in WAT was observed in obese and diabetic patients, and inhibition of adipose autophagy through targeted deletion of autophagy genes in mice improved anti-obesity phenotypes. In addition, active mitochondria clearance through activation of autophagy was required for beige/brown fat whitening – that is, conversion to white fat. However, inhibition of autophagy seemed detrimental in hypermetabolic conditions such as hepatic steatosis, atherosclerosis, thermal injury, sepsis, and cachexia through an increase in free fatty acid and glycerol release from WAT. The emerging concept of white fat browning–conversion to beige/brown fat–has been controversial in its anti-obesity effect through facilitation of weight loss and improving metabolic health. Thus, proper regulation of autophagy activity fit to an individual metabolic profile is necessary to ensure balance in adipose tissue metabolism and function, and to further prevent metabolic disorders such as obesity and diabetes. In this review, we summarize the effect of autophagy in adipose tissue browning in the context of obesity prevention and its potential as a promising target for the development of anti-obesity drugs.

Acute Inflammation and Metabolism

Inflammation is an adaptive process to the noxious stimuli that the human body is constantly exposed to. From the local inflammatory response to a full-blown systemic inflammation, a wide complex sequence of events occurs. Persistent immunosuppression and catabolism may ensue, until multiple organ failure finally sets in. And since clinically useful and specific biomarkers are lacking, diagnosis may come late. A thorough understanding of these events (how they begin, how they evolve, and how to modulate them) is imperative, but as yet poorly studied. This review aims to consolidate current knowledge of these events so that the management of these patients is not only evidence-based, but also built on an understanding of the inner workings of the human body in health and in disease.

Sex differences of inflammation in target organs, induced by intraperitoneal injection of lipopolysaccharide, depend on its dose

Purpose

The aim of our research was to study sex differences and the severity of inflammatory changes in target organs and the peculiarities of immunological disorders when low and high doses of lipopolysaccharide (LPS) were administered to rats.

Methods

Male and female 2- to 3-month-old Wistar rats (200–250 g) were injected intraperitoneally with Escherichia coli LPS in one of two doses: 1.5 or 15 mg/kg. In a day after the LPS injection, we studied endotoxin, corticosterone, sex steroids, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activity levels in the serum; morphological disorders in the lung, liver, thymus, and spleen; ex vivo production of IL-2, IL-4, tumor necrosis factor (TNF), and interferon γ (IFNγ) by splenic cells activated by ConA; and relative amount of T- and B-lymphocytes in the peripheral blood.

Results

After the injection of low-dose LPS, the serum endotoxin level increased only in males and was combined with a more pronounced inflammatory response in the lungs and thymus and an increase in ALT and AST activity levels without any changes in corticosterone level. After the injection of high-dose LPS, the inflammatory and pathological changes in the target organs manifested as severe endotoxemia and sex differences of pathological changes in the lungs and liver were not revealed. The level of production of IL-2, IL-4, IFNγ, and TNF by splenic cells and the number of T-lymphocytes, including cytotoxic cells, in the peripheral blood, decreased in males, which is an evidence of a pronounced suppression of the immune response.

Conclusion

We have shown that the morphofunctional changes in the organs of the immune system in females and males, as well as the intensity of the sex differences of inflammation, depend on the severity of systemic inflammatory response, induced by different doses of LPS.

Peroxidase-Mimicking Nanoassembly Mitigates Lipopolysaccharide-Induced Endotoxemia and Cognitive Damage in the Brain by Impeding Inflammatory Signaling in Macrophages

Oxidative stress during sepsis pathogenesis remains the most-important factor creating imbalance and dysregulation in immune-cell function, usually observed following initial infection. Hydrogen peroxide (H₂O₂), a potentially toxic reactive oxygen species (ROS), is excessively produced by pro-inflammatory immune cells during the initial phases of sepsis and plays a dominant role in regulating the pathways associated with systemic inflammatory immune activation. In the present study, we constructed a peroxide scavenger mannosylated polymeric albumin manganese dioxide (mSPAM) nanoassembly to catalyze the decomposition of H₂O₂ responsible for the hyper-activation of pro-inflammatory immune cells. In a detailed manner, we investigated the role of mSPAM nanoassembly in modulating the expression and secretion of pro-inflammatory markers elevated in bacterial lipopolysaccharide (LPS)-mediated endotoxemia during sepsis. Through a facile one-step solution-phase approach, hydrophilic bovine serum albumin reduced manganese dioxide (BM) nanoparticles were synthesized and subsequently self-assembled with cationic mannosylated disulfide cross-linked polyethylenimine (mSP) to formulate mSPAM nanoassembly. In particular, we observed that the highly stable mSPAM nanoassembly suppressed HIF1α expression by scavenging H₂O₂ in LPS-induced macrophage cells. Initial investigation revealed that a significant reduction of free radicals by the treatment of mSPAM nanoassembly has reduced the infiltration of neutrophils and other leukocytes in a local endotoxemia animal model. Furthermore, therapeutic studies in a systemic endotoxemia model demonstrated that mSPAM treatment reduced TNF-α and IL-6 inflammatory cytokines in serum, in turn circumventing organ damage done by the inflammatory macrophages. Interestingly, we also observed that the reduction of these inflammatory cytokines by mSPAM nanoassembly further prevented IBA-1 immuno-positive microglial cell activation in the brain and consequently improved the cognitive function of the animals. Altogether, the administration of mSPAM nanoassembly scavenged H₂O₂ and suppressed HIF1α expression in LPS-stimulated macrophages and thereby inhibited the progression of local and systemic inflammation as well as neuroinflammation in an LPS-induced endotoxemia model. This mSPAM nanoassembly system could serve as a potent anti-inflammatory agent, and we further anticipate its successful application in treating various inflammation-related diseases.

HMGB1 redox during sepsis. Redox Biol. 2017;13:600-607. [PMID: 28806702 PMCID: PMC5554965 DOI: 10.1016/j.redox.2017.08.001]

During sepsis, the alarmin HMGB1 is released from tissues and promotes systemic inflammation that results in multi-organ damage, with the kidney particularly susceptible to injury. The severity of inflammation and pro-damage signaling mediated by HMGB1 appears to be dependent on the alarmin's redox state. Therefore, we examined HMGB1 redox in kidney cells during sepsis. Using intravital microscopy, CellROX labeling of kidneys in live mice indicated increased ROS generation in the kidney perivascular endothelium and tubules during lipopolysaccharide (LPS)-induced sepsis. Subsequent CellROX and MitoSOX labeling of LPS-stressed endothelial and kidney proximal tubule cells demonstrated increased ROS generation in these cells as sepsis worsens. Consequently, HMGB1 oxidation increased in the cytoplasm of kidney cells during its translocation from the nucleus to the circulation, with the degree of oxidation dependent on the severity of sepsis, as measured in in vivo mouse samples using a thiol assay and mass spectrometry (LC-MS/MS). The greater the oxidation of HMGB1, the greater the ability of the alarmin to stimulate pro-inflammatory cyto-/chemokine release (measured by Luminex Multiplex) and alter mitochondrial ATP generation (Luminescent ATP Detection Assay). Administration of glutathione and thioredoxin inhibitors to cell cultures enhanced HMGB1 oxidation during sepsis in endothelial and proximal tubule cells, respectively. In conclusion, as sepsis worsens, ROS generation and HMGB1 oxidation increases in kidney cells, which enhances HMGB1's pro-inflammatory signaling. Conversely, the glutathione and thioredoxin systems work to maintain the protein in its reduced state.

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Endotoxins (LPS) increase cellular oxidative stress during sepsis.

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During its translocation, HMGB1 gets oxidized in the cytoplasm.

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Thioredoxin and glutathione keep HMGB1 in a reduced redox state during sepsis.

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HMGB1 oxidation enhances its stimulation of inflammatory cyto-/chemokine release.

Metabolic Adaptation Establishes Disease Tolerance to Sepsis

Sepsis is an often lethal syndrome resulting from maladaptive immune and metabolic responses to infection, compromising host homeostasis. Disease tolerance is a defense strategy against infection that preserves host homeostasis without exerting a direct negative impact on pathogens. Here, we demonstrate that induction of the iron-sequestering ferritin H chain (FTH) in response to polymicrobial infections is critical to establish disease tolerance to sepsis. The protective effect of FTH is exerted via a mechanism that counters iron-driven oxidative inhibition of the liver glucose-6-phosphatase (G6Pase), and in doing so, sustains endogenous glucose production via liver gluconeogenesis. This is required to prevent the development of hypoglycemia that otherwise compromises disease tolerance to sepsis. FTH overexpression or ferritin administration establish disease tolerance therapeutically. In conclusion, disease tolerance to sepsis relies on a crosstalk between adaptive responses controlling iron and glucose metabolism, required to maintain blood glucose within a physiologic range compatible with host survival.

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Ferritin is required to establish disease tolerance to sepsis

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Iron heme represses liver G6Pase during sepsis

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Ferritin counters G6Pase repression and sustains blood glucose levels after sepsis

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Liver gluconeogenesis is required to establish disease tolerance to sepsis

Analysis and modelling of septic shock microarray data using Singular Value Decomposition

Being a high throughput technique, enormous amounts of microarray data has been generated and there arises a need for more efficient techniques of analysis, in terms of speed and accuracy. Finding the differentially expressed genes based on just fold change and p-value might not extract all the vital biological signals that occur at a lower gene expression level. Besides this, numerous mathematical models have been generated to predict the clinical outcome from microarray data, while very few, if not none, aim at predicting the vital genes that are important in a disease progression. Such models help a basic researcher narrow down and concentrate on a promising set of genes which leads to the discovery of gene-based therapies. In this article, as a first objective, we have used the lesser known and used Singular Value Decomposition (SVD) technique to build a microarray data analysis tool that works with gene expression patterns and intrinsic structure of the data in an unsupervised manner. We have re-analysed a microarray data over the clinical course of Septic shock from Cazalis et al. (2014) and have shown that our proposed analysis provides additional information compared to the conventional method. As a second objective, we developed a novel mathematical model that predicts a set of vital genes in the disease progression that works by generating samples in the continuum between health and disease, using a simple normal-distribution-based random number generator. We also verify that most of the predicted genes are indeed related to septic shock.

Pediatric Multiple Organ Dysfunction Syndrome: Promising Therapies

OBJECTIVE

To describe the state of the science, identify knowledge gaps, and offer potential future research questions regarding promising therapies for children with multiple organ dysfunction syndrome presented during the Eunice Kennedy Shriver National Institute of Child Health and Human Development Workshop on Pediatric Multiple Organ Dysfunction Syndrome (March 26-27, 2015).

DATA SOURCES

Literature review, research data, and expert opinion.

STUDY SELECTION

Not applicable.

DATA EXTRACTION

Moderated by an expert from the field, issues relevant to the association of multiple organ dysfunction syndrome with a variety of conditions were presented, discussed, and debated with a focus on identifying knowledge gaps and research priorities.

DATA SYNTHESIS

Summary of presentations and discussion supported and supplemented by relevant literature.

CONCLUSIONS

Among critically ill children, multiple organ dysfunction syndrome is relatively common and associated with significant morbidity and mortality. For outcomes to improve, effective therapies aimed at preventing and treating this condition must be discovered and rigorously evaluated. In this article, a number of potential opportunities to enhance current care are highlighted including the need for a better understanding of the pharmacokinetics and pharmacodynamics of medications, the effect of early and optimized nutrition, and the impact of effective glucose control in the setting of multiple organ dysfunction syndrome. Additionally, a handful of the promising therapies either currently being implemented or developed are described. These include extracorporeal therapies, anticytokine therapies, antitoxin treatments, antioxidant approaches, and multiple forms of exogenous steroids. For the field to advance, promising therapies and other therapies must be assessed in rigorous manner and implemented accordingly.

Markers of Oxidative Stress and Clinical Outcome in Critically ill Septic Patients: A Preliminary Study from North India

INTRODUCTION

Sepsis is the leading cause of mortality in non-coronary Intensive Care Units (ICUs). Oxidative stress is one of the important features in pathogenesis of sepsis.

AIM

This study was undertaken to evaluate levels of oxidants and antioxidants in patients with sepsis admitted to ICU.

STUDY DESIGN

This was a non-interventional clinical case-control study undertaken at a tertiary level teaching hospital in New Delhi, India.

MATERIALS AND METHODS

Forty-six consecutive non-pediatric patients admitted to ICU with sepsis were included and subjected to detailed history, physical examination and investigations. Blood samples were drawn to evaluate oxidant Malondialdehyde (MDA) and antioxidant (alpha-tocopherol) levels. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Organ Dysfunction and/or Infection (ODIN) scores were calculated and patients followed up for outcomes. Twenty age and sex matched healthy subjects served as controls.

RESULTS

Mean levels of malondialdehyde were higher in patients than controls (17.2±3.8nm/ml versus 4.6±1.6nm/ml, p<0.001) while levels of alpha-tocopherol were lower (3.2±1.3μg/ml versus 9.9±2.0μg/ml, p<0.001). The mean APACHE II and ODIN scores were 18.1±9.3 and 1.7±1.3 respectively in patients. These scores were two to three fold higher in non survivor patients (n=22) in comparison with survivors (n=18) (p<0.001). There was no significant difference between the two groups in oxidants and antioxidants levels (p>0.05). However, a significant and positive correlation was observed between oxidant -antioxidant levels and APACHE II, ODIN and International Normalized Ratio (INR) scores in septic patients overall.

CONCLUSION

The oxidants in septic patients were significantly higher while antioxidants were significantly lower than healthy controls. There was also a significant correlation with APACHE II and ODIN scores. A large patient population based study may draw more specific conclusions.

Ethyl pyruvate protects against sepsis by regulating energy metabolism

Background

Ethyl pyruvate (EP) is a derivative of pyruvic acid that has been demonstrated to be a potential scavenger of reactive oxygen species as well as an anti-inflammatory agent. In this study, we investigated the protective effects of EP and its role in regulating the energy metabolism in the livers of cecal-ligation-and-puncture-induced septic mice.

Methods

The animals were treated intraperitoneally with 0.2 mL of Ringer’s lactate solution or an equivalent volume of Ringer’s lactate solution containing EP immediately after cecal ligation and puncture. Each mouse in the Sham group was only subjected to a laparotomy. At 30-, 60-, 180-, and 360-minute time points, we measured the histopathological alterations of the intestines, and the plasma levels of interleukin (IL)-1β, IL-6, IL-10, and tumor necrosis factor-α, and the total antioxidative capacity, malondialdehyde content, and lactate and lactate/pyruvate levels in livers. Furthermore, we detected the levels of adenosine triphosphate, total adenylate, and energy charge in the livers.

Results

Our results demonstrated that the administration of EP significantly improved the survival rate and reduced intestinal histological alterations. EP inhibited the plasma levels of IL-1β, IL-6, and tumor necrosis factor-α and increased the IL-10 level. EP significantly inhibited the elevation of the malondialdehyde, lactate, and lactate/pyruvate levels and enhanced the total antioxidative capacity levels in the liver tissues. The downregulation of the adenosine triphosphate, total adenylate, and energy charge levels in the liver tissues was reversed in the septic mice treated with EP.

Conclusion

The results suggest that EP administration effectively modulates the energy metabolism, which may be an important component in treatment of sepsis.