Search Results (8)

Preclinical evidence suggests that short chain fatty acids (SCFAs) produced by gut microbiota may impact body composition and muscle growth. While aging is implicated in negative alterations to the gut microbiome, exercise may mitigate these changes. Limited human evidence indicates that resistance training (RT) does not appreciably alter the gut microbiome in older adults, and no human study has examined whether resistance training differentially alters the gut microbiome and associated SCFAs between younger and older individuals. Therefore, we examined whether 10 weeks of RT differentially altered fecal microbiota composition, fecal and circulating SCFAs, and serum markers associated with gastrointestinal integrity in two cohorts of adults. Fecal and serum samples were obtained from untrained younger (22 ± 2 years, n = 12) and older (58 ± 8 years, n = 12) participants prior to and following 10 weeks of supervised twice-weekly full-body RT. Outcome measures immediately before (PRE) and after the intervention (POST) included dual X-ray absorptiometry for body composition, ultrasound for vastus lateralis (VL) thickness, 16S rRNA gene sequencing fecal microbiome data, serum and fecal SCFAs measured by gas chromatography, and serum intestinal fatty acid-binding protein 2 (FABP2), lipopolysaccharide-binding protein (LBP), and leucine-rich alpha-2 glycoprotein (LRG-1) quantified by enzyme-linked immunosorbent assays. Main effects and interactions were measured by repeated measures analysis of variance (group × time; G × T) for all dependent variables, and Spearman correlations were used to explore relationships among changes in relevant outcomes. The intervention significantly increased VL thickness and lean body mass (p < 0.05) equally in both groups. Although group differences in microbiome beta diversity were identified, no effects of age, time, or their interaction were observed for the alpha diversity measures. Seven SCFAs were detected in the fecal samples, albeit no significant age, time, or interaction effects were evident. In serum, acetic acid was the only SCFA detected, with no significant age, time, or interaction effects. Serum LRG1 decreased for all participants (p = 0.007) with higher levels in younger adults (p = 0.015), but no G × T interactions were observed for this marker, serum FABP2, or LBP. No significant correlations were observed among RT-induced changes in muscle mass-related outcomes and changes in fecal microbiome diversity, total or individual SCFAs, or serum FABP2/LBP/LRG-1. These results highlight that 10 weeks of RT largely does not affect fecal microbiota, associated SCFAs, or select markers of gastrointestinal integrity in untrained younger or older adults. Full article

Background/Objectives: The aim of this study was to evaluate potential biomarkers of bacterial translocation (lipopolysaccharide-binding protein (LBP) and soluble CD14 subtype (sCD14-ST)) and intestinal wall damage (intestinal fatty acid binding protein (I-FABP), Zonulin, and regenerating islet-derived protein-3α (REG3α)) in patients with multiple organ dysfunction syndrome (MODS). Methods: The study involved 327 patients divided into two groups: Group 1 comprised 227 patients with MODS (main group), while Group 2 comprised 100 patients with identical pathologies but without MODS (control group). To examine these biomarkers in the blood, venous blood was taken in the control group on the day of admission to the hospital, in patients with MODS on the first day of MODS staging, and later on Days 3 and 7 of its development. Levels of these markers in blood serum were determined by enzyme-linked immunosorbent assays according to the manufacturers’ instructions. Results: In the control group, values of all the investigated markers were lower than in the group of MODS patients (p < 0.0001). In the main group, the mortality rate was 44.9% (n = 102). The values of sCD14-ST on Day 1 and of I-FABP and REG3α on Days 1 and 3 were higher in deceased MODS patients (p < 0.05), while LBP levels on Day 7 were conversely lower in the deceased patients (p = 0.006). SOFA and APACHE II scores were higher in the deceased patients (p < 0.0001). Conclusions: In MODS patients, the increased I-FABP, REG3α, and sCD14-ST but decreased LBP levels may indicate increased intestinal wall permeability and bacterial translocation, which may exacerbate the course of multiple organ dysfunction and increase the risk of mortality. Despite the limitations of this study, the studied potential biomarkers can be considered noteworthy candidates for identifying MODS patients at high risk of mortality. Full article

Background/Objectives: Men are more susceptible to sepsis than women, but the underlying pathways have not been fully clarified. Lipopolysaccharide-binding protein (LBP) is an acute-phase protein that is highly elevated in sepsis. Experimental evidence shows that LBP increases to a much greater extent in male than in female mice following exposure to lipopolysaccharide. However, gender-specific studies of circulating LBP levels in sepsis patients are scarce. Methods: In the plasma of 189 patients with systemic inflammatory response syndrome (SIRS), sepsis, and septic shock, LBP levels were measured by enzyme-linked immunosorbent assay. Results: Patients with liver cirrhosis had reduced circulating LBP levels, regardless of gender. Further analysis within the non-cirrhotic patients showed no significant differences in LBP levels between sexes in patients with SIRS, sepsis, and septic shock. Ventilation, dialysis, and vasopressor therapy had no effect on LBP levels in either sex. A positive correlation between LBP and C-reactive protein was observed in the total cohort, males, and females. Infection with Gram-negative or Gram-positive bacteria had no effect on plasma LBP levels in males. However, female patients with Gram-negative infection had increased plasma LBP levels compared to females with negative and Gram-positive blood cultures, and 70 µg/mL LBP discriminates Gram-negative infections in females with a sensitivity of 88% and a specificity of 74%. Infection with SARS-CoV-2 did not change plasma LBP levels in either men or women. Female patients who did not survive had lower plasma LBP levels compared to female survivors and male non-survivors. Conclusions: This investigation highlights the influence of sex on plasma LBP levels in SIRS/sepsis patients, suggesting that LBP could be a sex-specific biomarker in critically ill patients. Full article

Sepsis leads to multi-organ failure due to aggressive systemic inflammation, which is one of the main causes of death clinically. This study aimed to evaluate whether ginseng sprout extracts (GSE) can rescue sepsis and explore its underlying mechanisms. C57BL/6J male mice (n = 15/group) were pre-administered with GSE (25, 50, and 100 mg/kg, p.o) for 5 days, and a single injection of lipopolysaccharide (LPS, 30 mg/kg, i.p) was administered to construct a sepsis model. Additionally, RAW264.7 cells were treated with LPS with/without GSE/its main components (Rd and Re) to explain the mechanisms corresponding to the animal-derived effects. LPS injection led to the death of all mice within 38 h, while GSE pretreatment delayed the time to death. GSE pretreatment also notably ameliorated LPS-induced systemic inflammation such as histological destruction in both the lung and liver, along with reductions in inflammatory cytokines, such as TNF-α, IL-6, and IL-1β, in both tissues and serum. Additionally, GSE markedly diminished the drastic secretion of nitric oxide (NO) by suppressing the expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2) in both tissues. Similar changes in TNF-α, IL-1β, NO, iNOS, and COX2 were observed in LPS-stimulated RAW264.7 cells, and protein expression data and nuclear translocation assays suggested GSE could modulate LPS-binding protein (LBP), Toll-like receptor 4 (TLR4), and NF-κB. Ginsenoside Rd could be a major active component in GSE that produces the anti-sepsis effects. Our data support that ginseng sprouts could be used as an herbal resource to reduce the risk of sepsis. The corresponding mechanisms may involve TLR4/NF-κB signaling and a potentially active component. Full article

Increasing evidence has demonstrated that oxidized low-density lipoproteins (oxLDL) and lipopolysaccharide (LPS) enhance accumulation of interleukin (IL)-1 beta-producing macrophages in atherosclerotic lesions. However, the potential synergistic effect of native LDL (nLDL) and LPS on the inflammatory ability and migration pattern of monocyte subpopulations remains elusive and is examined here. In vitro, whole blood cells from healthy donors (n = 20) were incubated with 100 μg/mL nLDL, 10 ng/mL LPS, or nLDL + LPS for 9 h. Flow cytometry assays revealed that nLDL significantly decreases the classical monocyte (CM) percentage and increases the non-classical monocyte (NCM) subset. While nLDL + LPS significantly increased the number of NCMs expressing IL-1 beta and the C-C chemokine receptor type 2 (CCR2), the amount of NCMs expressing the CX3C chemokine receptor 1 (CX3CR1) decreased. In vivo, patients (n = 85) with serum LDL-cholesterol (LDL-C) >100 mg/dL showed an increase in NCM, IL-1 beta, LPS-binding protein (LBP), and Castelli’s atherogenic risk index as compared to controls (n = 65) with optimal LDL-C concentrations (≤100 mg/dL). This work demonstrates for the first time that nLDL acts in synergy with LPS to alter the balance of human monocyte subsets and their ability to produce inflammatory cytokines and chemokine receptors with prominent roles in atherogenesis. Full article

Imperatorin (IMP) could downregulate several inflammatory transcription factor signaling pathways. Some studies have pointed out that IMP could interfere with toll-like receptor 4 (TLR4) signaling. This study evaluates how IMP interferes with the TLR4 co-receptors signaling through the protein-ligand docking model, Western blotting, immunofluorescence (IF), and atomic force microscopy (AFM) assays in lipopolysaccharide (LPS) stimulated macrophage-like RAW264.7 cells in vitro. The results of the protein-ligand docking demonstrate that IMP interferes with LPS binding to the LPS-binding protein (LBP), the cluster of differentiation 14 (CD14), and the toll-like receptor 4/myeloid differentiation factor 2 (TLR4/MD-2) co-receptors in LPS-stimulated RAW264.7 cells. Compared with TLR4 antagonist CLI-095 or dexamethasone, IMP could suppress the protein expressions of LBP, CD14, and TLR4/MD-2 in LPS-stimulated cells. Furthermore, the three-dimensional (3D) image assay of the AFM showed IMP could prevent the LPS-induced morphological change in RAW264.7 cells. Additionally, IMP could activate the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway, and it increased the antioxidative protein expression of heme oxygenase-1 (HO-1), superoxidase dismutase (SOD), and catalase (CAT). Our results are the first to reveal that the anti-inflammatory effect of IMP interferes with LPS binding to TLR4 co-receptor signaling and activates the antioxidative Nrf2 signaling pathway. Full article

The Limulus amebocyte assay (LAL) is increasingly used to quantify metabolic endotoxemia (ME), particularly in feeding studies. However, the assay was not intended to assess plasma at levels typically seen in ME. We aimed to optimize and validate the LAL assay under a range of pre-treatment conditions against the well-established lipopolysaccharide binding protein assay (LBP). Fifteen healthy overweight and obese males aged 28.8 ± 9.1years provided plasma. The LAL assay employed a range of pre-treatments; 70 °C for 15 and 30 min and 80 °C for 15 and 30 min, ultrasonication (70 °C for 10 min and then 40 °C for 10 min), and dilution (1:50, 1:75, 1:100, and 1:200 parts) or diluted using 0.5% pyrosperse. Seventeen different plasma pre-treatment methods employed prior to the use of the LAL analytical technique failed to show any relationships with either LBP, or body mass index (BMI; obesity), the biological trigger for ME (p > 0.05 for all). As expected, BMI positively correlated with LBP (r = 0.523, p = 0.052. No relationships were observed between LAL with any of the sample pre-treatments and LBP or BMI. In its current form, the LAL assay is unsuitable for detecting levels of endotoxin typically seen in ME. Full article

In designing a bacteria biosensor, various issues must be addressed: the specificity of bacteria recognition, the immobilization of biomolecules that act as the bacteria receptor, and the selectivity of sensor surface. The aim of this paper was to examine how the biofunctionalized surface of Ti, Au, and Ru metals reacts in contact with strains of Escherichia coli (E. coli). The focus on metal surfaces results from their future use as electrodes in high frequency biosensors, e.g., resonant circuits or transmission-line sections. First, the surfaces of different metals were chemically functionalized with 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde or with 3-glycidylooxypropyltrimethoxysilane (GPTMS) followed by N-(5-amino-1-carboxypentyl) iminodiacetic acid (AB-NTA) and NiCl₂. Secondly, the lipopolysaccharide binding protein (LBP), polyclonal anti-Escherichia coli antibody and bacteriophage protein gp37 were tested as bacteria receptors. The selectivity and specificity have been confirmed by the Enzyme-Linked Immunosorbent Assay (ELISA) and visualized by scanning electron microscopy at low landing energies. We noticed that LBP, polyclonal antibody, and gp37 were successfully immobilized on all studied metals and recognized the E. coli bacteria selectively. However, for the antibody, the highest reactivity was observed when Ti surface was modified, whereas the bacteria binding was comparable between LBP and gp37 on the functionalized Ru surfaces, independent from modification. Thus, all surfaces were biocompatible within the scope of biosensor functionality, with titanium functionalization showing the best performance. Full article