1. Prevention of Metabolic Endotoxemia With Pro- and Prebiotics
Henri Alexandre Giblot Ducray, Ludmila Globa, Oleg Pustovyy, Vitaly Vodyanoy Iryna Sorokulova Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849
INTRODUCTION
Obesity and diabetes are metabolic diseases associated with chronic low-grade inflammation. Recent scientific data identified lipopolysaccarides (LPS – toxic outer component of Gram-negative bacteria) as a triggering factor causing this inflammation (Serino et al., 2009, Fig.1).
RESULTS
Histology. Morphometric study of intestine showed that heat stress significantly inhibited villi height and total mucosal thickness in rats (Figures 3,4). Oral administration of BSB3 strain or prebiotic EH before stress protected intestine from the harmful effect of heat.
Fig. 3 Effect of BSB3 on intestinal Fig. 4. Effect of EH on intestinal morphology
morphology
Serum LPS concentration - Level of LPS significantly increased in serum of heat-stressed animals, which received PBS before stress exposure (Figure 5,6). Concentration of LPS in serum of rats, pre-treated with BSB3 or EH before heat stress, was not significantly changed in comparison with non-stressed animals.
Fig. 5 Effect of BSB3 on serum LPS Fig. 6. Effect of EH on serum LPS level
level
CONCLUSION :Pre-treatment with BSB3 or EH was effective in prevention of LPS release into circulation in rats exposed to heat.
ACKNOWLEDGEMENT: This work was supported by Auburn University Funds # and by Embria Health Sciences LLC.
REFERENCES: Serino et al., Intestinal microflora and metabolic diseases, Diabetes & Metabolism , 2009, 35, 262–272.
Elevated level of LPS in the bloodstream (metabolic endotoxemia) leads to release of pro-inflammatory cytokines and oxidative stress, which are associated with obesity. The presence of LPS in the systemic circulation is an indicator of gastrointestinal barrier disruption, resulted from the changes in the gut microbiota. Lowering of LPS concentration in blood is discussed as a potent strategy for the control of metabolic diseases.
PBS/25 oC (Control)
PBS/45oC (Heat stress)
EH/25oC (Control)
EH/45oC (Heat stress)
100 µm
OBJECTIVE
The main aim of this study was to analyze the efficacy of Bacillus probiotic bacteria (BSB3) and prebiotic supplement (EH) on preventing the release of LPS during heat stress.
METHODS
Ethics Statement - All animal procedures were approved by the Auburn University Institutional Animal Care and Use.
Bacillus probiotic strain - B. subtilis BSB3 with promising probiotic activity was used in this study; Prebiotic EH - supplement, based on dry fermented Saccharomyces cerevisiae.
Animals - Adult male Sprague–Dawley rats (Harlan Laboratories, USA) weighing 250–300 g were used in this study.
Histological analysis –Small intestine samples were removed from each rat, fixed in Bouin’s Fixative, embedded in paraffin, sectioned at 6 micrometers, slide mounted, hematoxylin and eosin (H&E) stained, and cover-slipped. Intestinal villi height and total mucosal thickness were measured for each sample using a high resolution microscope system.
Experimental design. Rats were treated by oral gavage with B. subtilis probiotic or PBS twice a day for two days. For prebiotic experiments rats were treated orally with EH product or PBS once a day for 14 days. Half of the rats of each group were exposed to heat stress (45o C, relative humidity 55% for 25 min) while the remaining rats were placed at identical conditions but at 25oC (Figure 2).
Serum concentration of LPS was analyzed by rat LPS ELISA kit (NeoBioLab, Cambridge, MA, USA) and by the Pierce LAL Chromogenic Endotoxin Quantitation Kit (Thermo Scientific, Rockford, IL) using the Limulus Amebocyte Lysate (LAL) assay.
Fig.2 Experimental design