Metabolic Endotoxemia, Feeding Studies and the Use of the Limulus Amebocyte (LAL) Assay; Is It Fit for Purpose?

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.

Download Full-text

Anthropometric indices, lipid profile, and lipopolysaccharide-binding protein levels in metabolic endotoxemia: A case-control study in Calabar Metropolis, Nigeria

Journal of Acute Disease ◽

10.4103/2221-6189.281320 ◽

2020 ◽

Vol 9 (2) ◽

pp. 67

Author(s):

EkongRaymond Eworo ◽

EdmundRichard Egbe ◽

ZibrilA Okhormhe ◽

BasseyK Offor ◽

BasseyIkoedem Uduak ◽

...

Keyword(s):

Lipid Profile ◽

Case Control Study ◽

Binding Protein ◽

Case Control ◽

Lipopolysaccharide Binding Protein ◽

Anthropometric Indices ◽

Protein Levels ◽

Metabolic Endotoxemia ◽

Control Study ◽

Lipopolysaccharide Binding

Download Full-text

Circulating Lipopolysaccharide-Binding Protein and Carotid Intima-Media Thickness in Obstructive Sleep Apnea

Physiological Research ◽

10.33549/physiolres.933632 ◽

2018 ◽

pp. 69-78 ◽

Cited By ~ 2

Author(s):

I. TROJOVA ◽

M. KOZAROVA ◽

D. PETRASOVA ◽

Z. MALACHOVSKA ◽

I. PARANICOVA ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Intima Media Thickness ◽

Carotid Intima Media Thickness ◽

Lipopolysaccharide Binding Protein ◽

Media Thickness ◽

Obstructive Sleep ◽

Metabolic Endotoxemia ◽

Lipopolysaccharide Binding ◽

Early Atherosclerosis

Circulating lipopolysaccharide-binding protein (LBP), a metabolic endotoxemia marker, was identified as an independent predictor of atherosclerosis. Although increases in carotid intima-media thickness (CIMT) were repeatedly reported in obstructive sleep apnea (OSA), neither the role of OSA in metabolic endotoxemia nor of LBP in early atherosclerosis were explored in patients with OSA. At a tertiary university hospital we investigated the relationships between OSA, LBP and CIMT in 117 men who underwent full polysomnography and CIMT assessment by B-mode ultrasound. Circulating LBP concentrations and average CIMT increased from patients without OSA to those with mild-moderate and severe OSA (from 32.1±10.3 to 32.3±10.9 to 38.1±10.3 μg.ml-1, p=0.015; from 0.52±0.09 to 0.58±0.06 to 0.62±0.10 mm, p=0.004, respectively). Oxygen desaturation index (ODI) was a predictor of serum LBP levels independent of age, waist-to-hip ratio (WHR), smoking, hypertension, HDL cholesterol, triglycerides and fasting glucose [p (ANOVA)=0.002, r2=0.154], with no independent effect of the ODI*WHR interaction term on LBP. Furthermore, serum LBP predicted CIMT independently of known risk factors of atherosclerosis including obesity (p<0.001, r2=0.321). Our results suggest that OSA severity contributes to metabolic endotoxemia in patients with OSA independently of obesity, and that LBP might represent a contributing factor promoting early atherosclerosis in such patients.

Download Full-text

Consumption of pomegranate decreases plasma lipopolysaccharide-binding protein levels, a marker of metabolic endotoxemia, in patients with newly diagnosed colorectal cancer: a randomized controlled clinical trial

Food & Function ◽

10.1039/c8fo00264a ◽

2018 ◽

Vol 9 (5) ◽

pp. 2617-2622 ◽

Cited By ~ 11

Author(s):

A. González-Sarrías ◽

M. A. Núñez-Sánchez ◽

M. A. Ávila-Gálvez ◽

T. Monedero-Saiz ◽

F. J. Rodríguez-Gil ◽

...

Keyword(s):

Colorectal Cancer ◽

Time Dependent ◽

Controlled Clinical Trial ◽

Newly Diagnosed ◽

Randomized Controlled Clinical Trial ◽

Lipopolysaccharide Binding Protein ◽

Protein Levels ◽

Randomized Controlled ◽

Metabolic Endotoxemia ◽

Lipopolysaccharide Binding

Consumption of pomegranate decreases, in a time-dependent fashion, metabolic endotoxemia in patients with newly diagnosed colorectal cancer.

Download Full-text

Molecular cloning of cDNA for lipopolysaccharide-binding protein from the hemolymph of the American cockroach, Periplaneta americana. Similarity of the protein with animal lectins and its acute phase expression

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)98841-1 ◽

1991 ◽

Vol 266 (20) ◽

pp. 13318-13323

Author(s):

T. Jomori ◽

S. Natori

Keyword(s):

Molecular Cloning ◽

Acute Phase ◽

Periplaneta Americana ◽

Binding Protein ◽

American Cockroach ◽

Lipopolysaccharide Binding Protein ◽

Lipopolysaccharide Binding

Download Full-text

Higher Lipopolysaccharide Binding Protein and Chemerin Concentrations Were Associated with Metabolic Syndrome Features in Pediatric Subjects with Abdominal Obesity during a Lifestyle Intervention

Nutrients ◽

10.3390/nu13020289 ◽

2021 ◽

Vol 13 (2) ◽

pp. 289

Author(s):

Amelia Marti ◽

Isabel Martínez ◽

Ana Ojeda-Rodríguez ◽

María Cristina Azcona-Sanjulian

Keyword(s):

Metabolic Syndrome ◽

Children And Adolescents ◽

Lifestyle Intervention ◽

Abdominal Obesity ◽

Plasma Levels ◽

Intervention Program ◽

Binding Protein ◽

Controlled Trial ◽

Lipopolysaccharide Binding Protein ◽

Lipopolysaccharide Binding

Background: Elevated circulating plasma levels of both lipopolysaccharide-binding protein (LBP) and chemerin are reported in patients with obesity, but few studies are available on lifestyle intervention programs. We investigated the association of both LBP and chemerin plasma levels with metabolic syndrome (MetS) outcomes in a lifestyle intervention in children and adolescents with abdominal obesity Methods: Twenty-nine patients enrolled in a randomized controlled trial were selected. The lifestyle intervention with a 2-month intensive phase and a subsequent 10-month follow-up consisted of a moderate calorie-restricted diet, recommendations to increase physical activity levels, and nutritional education. Results: Weight loss was accompanied by a significant reduction in MetS prevalence (−43%; p = 0.009). Chemerin (p = 0.029) and LBP (p = 0.033) plasma levels were significantly reduced at 2 months and 12 months, respectively. At the end of intervention, MetS components were associated with both LBP (p = 0.017) and chemerin (p < 0.001) plasma levels. Conclusions: We describe for the first time a reduction in both LBP and chemerin plasma levels and its association with MetS risk factors after a lifestyle intervention program in children and adolescents with abdominal obesity. Therefore, LBP and chemerin plasma levels could be used as biomarkers for the progression of cardiovascular risk in pediatric populations.

Download Full-text

Exogenous 5-azaCitidine accelerates flowering and external GA3 increases ornamental value in Iranian Anemone accessions

Scientific Reports ◽

10.1038/s41598-021-86940-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Vahideh Yari ◽

Zeynab Roein ◽

Atefeh Sabouri

Keyword(s):

Morphological Characteristics ◽

Flower Longevity ◽

Cut Flowers ◽

Stem Height ◽

Flowering Stage ◽

Potted Plants ◽

Dormancy Period ◽

Treatment Conditions ◽

Number Of Leaves ◽

Pre Treatment

AbstractThe Anemone genus is a tuberous geophyte which undergoes a dormancy period during unfavorable environmental conditions for growth. Five species of the Anemone genus naturally grow in several regions of Iran. The diverse uses of Anemone in gardens for landscaping, cut flowers, and potted plants indicate its high ornamental potential. Its dormancy and flowering are influenced by various factors. The present paper was conducted to explore the flowering behavior of Anemone accessions in response to different pre-treatments. For this purpose, tubers of 18 Anemone accessions (A. coronaria and A. biflora) were collected from natural regions of six provinces in Iran. These tubers were subjected to different conditions of non-chilling (20 °C, 90 days), chilling (4 °C, 90 days), GA3 (150 mgL-1; 24 h), and 5-azaCitidine (5-azaC; 40 µM; 24 h) prior to the cultivation. Most of the accessions were able to enter the flowering stage without chilling. The shortest period for the sprouting of tubers (16.89 ± 7.83 days) belonged to 5-azaC pre-treatment. In addition, this treatment accelerated the flowering time (about 30 days earlier) and diameter of the stem, bud, and flower. Morphological characteristics, such as stem height, number of leaves, bud, and petal and the longevity of flowers on the plant were significantly affected by GA3 pre-treatment. Our results indicated a positive correlation between flower length, stem height, and stem diameter with flower longevity under different pre-treatment conditions. The present study demonstrated that accessions Anm3, Anm12, and Anm18 had ornamental values higher than the population mean across four conditions.

Download Full-text

Microbiome-Metabolomics Reveals Prebiotic Benefits of Fucoidan Supplementation in Mice

Journal of Marine Science and Engineering ◽

10.3390/jmse9050505 ◽

2021 ◽

Vol 9 (5) ◽

pp. 505

Author(s):

Jingyi Yuan ◽

Song Qin ◽

Wenjun Li ◽

Yubing Zhang ◽

Yuting Wang ◽

...

Keyword(s):

Lipid Metabolism ◽

Triglyceride Level ◽

Lactobacillus Reuteri ◽

Binding Protein ◽

Serum Triglyceride ◽

Serum Triglyceride Level ◽

Lipopolysaccharide Binding Protein ◽

Lactobacillus Gasseri ◽

Lactobacillus Animalis ◽

Lipopolysaccharide Binding

Fucoidan is a kind of polysaccharide with antitumor and antioxidant properties, which is mainly isolated from brown algae. Although there are many reports about the prebiotic effects of polysaccharides on hosts, there are few reports about the effects of fucoidan on blood biochemical indexes, intestinal microbiome, and metabolic function on healthy hosts. We applied 16S rRNA gene amplicon sequencing and LC-MS/MS metabolomics to evaluate the changes in the gut microbiome and metabolite profiles of fucoidan treatment in mice over 10 weeks. Fucoidan treatment modulated lipid metabolism, including significantly decreasing serum triglyceride level in healthy mice. Fucoidan also significantly inhibited serum lipopolysaccharide-binding protein (LBP) concentration, a biomarker of endotoxemia. Correlation analysis further showed that Lactobacillus animalis populations that were enriched by fucoidan demonstrated significantly negative correlations with serum triglyceride level. The abundance of Lactobacillus gasseri and Lactobacillus reuteri, increased by fucoidan supplementation, demonstrated significantly negative correlation with lipopolysaccharide-binding protein levels. Lactobacillus gasseri also demonstrated significantly positive correlations with three tryptophan-related metabolites, including indoleacrylic acid, 3-indoleacrylic acid, and 5-hydroxytryptamine, which were all increased by fucoidan administration. Combined with the previous evidence, the results indicate that fucoidan exerts prebiotic effects, such as lipid metabolism suppression and metabolic endotoxemia suppression, by modulating the abundance of gut microbiota, such as Lactobacillus animalis, Lactobacillus gasseri, and Lactobacillus reuteri, as well as microbiota-dependent metabolites, such as tryptophan-related metabolites.

Download Full-text