Metabolomics in pediatric lower respiratory tract infections and sepsis: a literature review.

Lower respiratory tract infections (LRTIs) are a leading cause of morbidity and mortality in children. The ability of healthcare providers to diagnose and prognose LRTIs in the pediatric population remains a challenge, as children can present with similar clinical features regardless of the underlying pathogen or ultimate severity. Metabolomics, the large-scale analysis of metabolites and metabolic pathways offers new tools and insights that may aid in diagnosing and predicting the outcomes of LRTIs in children.

Comparison of Two Automated Targeted Metabolomics Programs to Manual Profiling by an Experienced Spectroscopist for H-NMR Spectra.

Automated programs that carry out targeted metabolite identification and quantification using proton nuclear magnetic resonance spectra can overcome time and cost barriers that limit metabolomics use. However, their performance needs to be comparable to that of an experienced spectroscopist. A previously analyzed pediatric sepsis data set of serum samples was used to compare results generated by the automated programs rDolphin and BATMAN with the results obtained by manual profiling for 58 identified metabolites.

Metabolomics and Inflammatory Mediator Profiling for the Differentiation of Life-Threatening and Non-Severe Appendicitis in the Pediatric Population.

While children with appendicitis often have excellent clinical outcomes, some develop life-threatening complications including sepsis and organ dysfunction requiring pediatric intensive care unit (PICU) support. Our study applied a metabolomics and inflammatory protein mediator (IPM) profiling approach to determine the bio-profiles of children who developed severe appendicitis compared with those that did not. We performed a prospective case-control study of children aged 0-17 years with a diagnosis of appendicitis.

Novel molecular biomarkers and diagnosis of acute appendicitis in children.

Reliable and efficient diagnosis of pediatric appendicitis is essential for the establishment of a clinical management plan and improvement of patient outcomes. Current strategies used to diagnose a child presenting with a suspected appendicitis include laboratory studies, clinical scores and diagnostic imaging. Although these modalities work in conjunction with each other, one optimal diagnostic strategy has yet to be agreed upon.

Metabolic Framework for the Improvement of Autism Spectrum Disorders by a Modified Ketogenic Diet: A Pilot Study.

The ketogenic diet (KD) can improve the core features of autism spectrum disorders (ASD) in some children, but the effects on the overall metabolism remain unclear. This pilot study investigated the behavioral parameters in relation to blood metabolites and trace elements in a cohort of 10 typically developed controls (TC) and 17 children with ASD at baseline and following 3 months of treatment with a modified KD regimen. A nontargeted, multiplatform metabolomic approach was employed, including gas chromatography-mass spectrometry, H nuclear magnetic resonance spectroscopy, and inductively coupled plasma-mass spectrometry.

Distinct Gut Microbiota and Serum Metabolites in Response to Weight Loss Induced by Either Dairy or Exercise in a Rodent Model of Obesity.

Energy imbalance is a primary cause of obesity. While the classical approach to attenuate weight gain includes an increase in energy expenditure through exercise, dietary manipulation such as the inclusion of dairy products has also been proven effective. In the present study, we explored the potential mechanisms by which dairy and exercise attenuate weight gain in diet-induced obese rats.

Metabolite Profiling of Clinical Cancer Biofluid Samples by NMR Spectroscopy.

Metabolomics is a comprehensive characterization of the small polar molecules (metabolites) in different biological systems. One of the analytical platforms commonly used to study metabolic alterations in biofluid samples is proton nuclear magnetic resonance (H NMR) spectroscopy. NMR spectroscopy is very specific, quantitative, and highly reproducible.

Impact of dietary fiber supplementation on modulating microbiota-host-metabolic axes in obesity.

Low dietary fiber intake is associated with higher rates of microbiota-associated chronic diseases such as obesity. Low-fiber diets alter not only microbial composition but also the availability of metabolic end products derived from fermentation of fiber. Our objective was to examine the effects of dietary fiber supplementation on gut microbiota and associated fecal and serum metabolites in relation to metabolic markers of obesity.

Biomarker Phenotype for Early Diagnosis and Triage of Sepsis to the Pediatric Intensive Care Unit.

Early diagnosis and triage of sepsis improves outcomes. We aimed to identify biomarkers that may advance diagnosis and triage of pediatric sepsis. Serum and plasma samples were collected from young children (1-23 months old) with sepsis on presentation to the Pediatric Intensive Care Unit (PICU-sepsis, n = 46) or Pediatric Emergency Department (PED-sepsis, n = 58) and PED-non-sepsis patients (n = 19).

Sarcopenia and myosteatosis are accompanied by distinct biological profiles in patients with pancreatic and periampullary adenocarcinomas.

Introduction: Pancreatic and periampullary adenocarcinomas are associated with abnormal body composition visible on CT scans, including low muscle mass (sarcopenia) and low muscle radiodensity due to fat infiltration in muscle (myosteatosis). The biological and clinical correlates to these features are poorly understood.

Methods: Clinical characteristics and outcomes were studied in 123 patients who underwent pancreaticoduodenectomy for pancreatic or non-pancreatic periampullary adenocarcinoma and who had available preoperative CT scans.

Serum Metabolite Profiles Are Altered by Erlotinib Treatment and the Integrin α1-Null Genotype but Not by Post-Traumatic Osteoarthritis.

The risk of developing post-traumatic osteoarthritis (PTOA) following joint injury is high. Furthering our understanding of the molecular mechanisms underlying PTOA and/or identifying novel biomarkers for early detection may help to improve treatment outcomes. Increased expression of integrin α1β1 and inhibition of epidermal growth factor receptor (EGFR) signaling protect the knee from spontaneous OA; however, the impact of the integrin α1β1/EGFR axis on PTOA is currently unknown.

Development of metabolic and inflammatory mediator biomarker phenotyping for early diagnosis and triage of pediatric sepsis.

Introduction: The first steps in goal-directed therapy for sepsis are early diagnosis followed by appropriate triage. These steps are usually left to the physician's judgment, as there is no accepted biomarker available. We aimed to determine biomarker phenotypes that differentiate children with sepsis who require intensive care from those who do not.

Metabolic analysis of knee synovial fluid as a potential diagnostic approach for osteoarthritis.

Osteoarthritis (OA) is a leading cause of chronic joint pain in the older human population. Diagnosis of OA at an earlier stage may enable the development of new treatments to one day effectively modify the progression and prognosis of the disease. In this work, we explore whether an integrated metabolomics approach could be utilized for the diagnosis of OA.

Integration of metabolic and inflammatory mediator profiles as a potential prognostic approach for septic shock in the intensive care unit.

Introduction: Septic shock is a major life-threatening condition in critically ill patients and it is well known that early recognition of septic shock and expedient initiation of appropriate treatment improves patient outcome. Unfortunately, to date no single compound has shown sufficient sensitivity and specificity to be used as a routine biomarker for early diagnosis and prognosis of septic shock in the intensive care unit (ICU). Therefore, the identification of new diagnostic tools remains a priority for increasing the survival rate of ICU patients.

Metabolomics in critical care medicine: a new approach to biomarker discovery.

Purpose: To present an overview and comparison of the main metabolomics techniques (1H NMR, GC-MS, and LC-MS) and their current and potential use in critical care medicine.

Source: This is a focused review, not a systematic review, using the PubMed database as the predominant source of references to compare metabolomics techniques.

Principal Findings: 1H NMR, GC-MS, and LC-MS are complementary techniques that can be used on a variety of biofluids for metabolomics analysis of patients in the Intensive Care Unit (ICU).

Metabolic profiling of synovial fluid in a unilateral ovine model of anterior cruciate ligament reconstruction of the knee suggests biomarkers for early osteoarthritis.

Joint injuries and subsequent osteoarthritis (OA) are the leading causes of chronic joint disease. In this work, we explore the possibility of applying magnetic resonance spectroscopy-based metabolomics to detect host responses to an anterior cruciate ligament (ACL) reconstruction injury in synovial fluid in an ovine model. Using multivariate statistical analysis, we were able to distinguish post-injury joint samples (ACL and sham surgery) from the uninjured control samples, and as well the ACL surgical samples from sham surgery.

Metabolic changes associated with selenium deficiency in mice.

Selenium (Se), which is a central component for the biosynthesis and functionality of selenoproteins, plays an important role in the anti-oxidative response, reproduction, thyroid hormone metabolism and the protection from infection and inflammation. However, dietary Se effects have not well been established to date and the available studies often present contradictory results. To obtain a better understanding of Se intake and its influence on the metabolism of living systems, we have utilized a metabolomics approach to gain insight into the specific metabolic alterations caused by Se deficiency in mice.

Metabolic profiling of serum samples by 1H nuclear magnetic resonance spectroscopy as a potential diagnostic approach for septic shock.

Objectives: To determine whether a nuclear magnetic resonance-based metabolomics approach can be useful for the early diagnosis and prognosis of septic shock in ICUs.

Design: Laboratory-based study.

Setting: University research laboratory.

Metabolomics as a novel approach for early diagnosis of pediatric septic shock and its mortality.

Rationale: Septic shock is a significant cause of morbidity and mortality in the pediatric population. Early recognition of septic shock and appropriate treatment increase survival rate; thus, developing new diagnostic tools may improve patients' outcomes.

Objectives: To determine whether a metabolomics approach could be useful in the diagnosis and prognosis of septic shock in pediatric intensive care unit (PICUs).

Synthesis, biological activity and solution structure of new analogues of the antimicrobial Gramicidin S.

Gramicidin S (GS) is a cyclo-decapeptide antibiotic isolated from Bacillus brevis. The structural studies have shown that GS forms a two-stranded antiparallel β-sheet imposed by two II' β-turns. Despite its wide Gram+ and Gram- antimicrobial spectrum, GS is useless in therapy because of its high hemotoxicity in humans.

Antimicrobial and conformational studies of the active and inactive analogues of the protegrin-1 peptide.

The natural antimicrobial cationic peptide protegrin-1 displays a broad spectrum of antimicrobial activity and rapidly kills pathogens by interacting with their cell membrane. We investigated the structure-activity relationships of three protegrin-1 analogues: IB-367 (RGGLCYCRGRFCVCVGR-NH(2)), BM-1 (RGLCYCRGRFCVCVG-NH(2)) and BM-2 (RGLCYRPRFVCVG-NH(2)). Our antimicrobial and antifungal activity studies of these peptides showed that BM-1 was much more active than IB-367 against Gram-positive bacteria and fungi, whereas BM-2 was inactive.

Conformational solution studies of the anti-microbial temporin A retro-analogues by using NMR spectroscopy.

Temporin A (TA) is a small, basic and highly hydrophobic peptide, isolated from the skin of the European red frog, Rana temporaria. The TA (FLPLIGRVLSGIL-NH2) displays a broad spectrum of anti-microbial activity against Gram-positive bacteria and fungi Candida albicans. In this study we investigate the solution structure of two TA retro-analogues, (6-1)(7-13)-TA (GILPLFRVLSGIL-NH2) and retro-TA (LIGSLVRGILPLF-NH2) by using nuclear magnetic resonance (NMR).

Temporin A and its retro-analogues: synthesis, conformational analysis and antimicrobial activities.

Temporin A (TA) is a hydrophobic peptide isolated from the skin of the European red frog Rana temporaria. Strong antimicrobial activity against gram-positive cocci and Candida, as well as its small molecular weight (10-13 aa residues), makes TA an interesting antimicrobial compound. However, its synthesis is rather problematic.