Chronic Oral Administration of Mineral Oil Compared With Corn Oil: Effects on Gut Permeability and Plasma Inflammatory and Lipid Biomarkers

We investigated the effects of chronic oral administration of mineral oil, versus corn oil as control, on intestinal permeability, inflammatory markers, and plasma lipids in APOE*3-Leiden.CETP mice. Mice received mineral oil or corn oil 15 or 30 μL/mouse/day for 16 weeks (15 mice/group). Intestinal permeability was increased with mineral versus corn oil 30 µL/day, shown by increased mean plasma FITC-dextran concentrations 2 h post-administration (11 weeks: 1.5 versus 1.1 μg/ml, p = 0.02; 15 weeks: 1.7 versus 1.3 μg/ml, p = 0.08). Mean plasma lipopolysaccharide-binding protein levels were raised with mineral versus corn oil 30 µL/day (12 weeks: 5.8 versus 4.4 μg/ml, p = 0.03; 16 weeks: 5.8 versus 4.5 μg/ml, p = 0.09), indicating increased intestinal bacterial endotoxin absorption and potential pro-inflammatory effects. Plasma cholesterol and triglyceride concentrations were decreased with mineral oil, without affecting liver lipids among treated groups. Fecal neutral sterol measurements indicated increased fecal cholesterol excretion with mineral oil 30 µL/day (+16%; p = 0.04). Chronic oral administration of mineral oil in APOE*3-Leiden.CETP mice increased intestinal permeability, with potential pro-inflammatory effects, and decreased plasma cholesterol and triglyceride levels. Our findings may raise concerns about the use of mineral oil as a placebo in clinical studies.

California Strawberry Consumption Alters Gut Microbiome in Healthy Participants: A Pilot Study

Objectives Based on the polyphenol and fiber content of strawberries (SB), it was our hypothesis that daily consumption of California strawberries will lead to changes in the composition of the intestinal microbiota, and concentration of fecal cholesterol and bile acid (BA) microbial metabolites. Methods We performed a randomized, double blind, parallel design intervention study. 28 healthy adults were randomized to either daily consumption of 26 g of SB powder (2 servings of fresh SB) or placebo (PL) powder for 4 wks. Stool samples were collected at baseline (BL), 4 and 6 wks (2 wks no SB/PL). Fecal microbiota was analyzed by 16S rDNA sequencing of the V4 region; fecal cholesterol, coprostanol, cholestanol, cholic acid (primary BA), chenodeoxycholic acid (primary BA), deoxycholic acid (2ndBA), lithocholic acid (2ndBA) by gas chromatography, serum cholesterol, triglyceride by colorimetric assay and serum pelargonidin glucuronide (PG) by high performance liquid chromatography. Results Serum PG, a SB anthocyanin, was found in all participants in the SB group. Two participants in the PL group showed serum PG and were excluded from the analyses. Daily SB increased the abundance of Christensenellaceae, Bifidobacteriaceae, Verrucomicrobiaceae and multiple members of the Lachnospiraceae, Ruminococcaceae family, and decreased significantly Alcaligenaceae/Sutterella comparing BL to wk4. Comparing the change from BL to wk4 between the SB and PL group, we found increased abundance of Alcaligenaceae/Sutterella and several members of the Clostridia class including Lachnopsiraceae and Ruminococcaceae and a decrease in Clostridiaceae. Comparing wk 4 to wk 6, we observed a reversal of Clostridiales/Christensenellaceae, Verrucomicrobiaceae, and Alcaligenaceae/Sutterella. No effects on alpha and beta diversity were observed. No significant difference in serum and fecal cholesterol, BA and bacterial metabolites was observed between SB and PL groups. Five participants did not form coprostanol. Comparing coprostanol producers to non-producers at baseline showed that most differences were observed in the Lachnospiraceae, Ruminococcaceae and Bacteroidaceae families. Conclusions SB consumption altered the gut microbiota, which was partially reversed after 2 wks of customary diet without SB. Funding Sources California Strawberry Commission.

Unripe banana flour (Musa cavendishii) promotes decrease in weight gain and elimination of fecal cholesterol in Wistar rats

Purpose The purpose of this study is to evaluate the chemical composition of unripe banana flour from Southeast Brazil and verify its nutritional, physiological and biochemical properties in adult Wistar rats. Design/methodology/approach Analysis of soluble solids, titratable acidity, pH, moisture, ash, lipids, proteins, carbohydrate, resistant and total starch and energy was obtained. In all, 18 male Wistar rats were given different concentrations of unripe banana flour (0, 10 and 20 per cent) and these assessments were performed: feed, caloric and water intake; weight gain; coefficient of food efficiency; weight of organs; body, tibia and femur length; total mineral of bones; and biochemistry of blood, hepatic fluids and feces. Findings Unripe banana flour showed a potential for weight control as well as increased fecal cholesterol excretion. These results showed the potential of unripe banana flour for obesity treatment and lipid excretion. Nevertheless, plasma triacylglycerol levels increased in the animals that received the largest amount of banana flour (20 per cent w/w), possibly because of the large amount of resistant starch in the flour, indicating the need for additional studies to confirm the mechanisms responsible for this increase. Originality/value Unripe banana flour may promote beneficial health effects (such as weight control and increased elimination of cholesterol in feces); however, the large amount of resistant starch present may be responsible for an increase in blood triacyglycerol.

Abstract 424: Transintestinal Cholesterol Excretion Can Drive Massive Cholesterol Elimination in Mice

High plasma cholesterol levels increase the risk of cardiovascular disease (CVD). Transintestinal Cholesterol Excretion (TICE) is a recently emerged pathway of cholesterol removal and has the potential to lower plasma cholesterol levels and confer protection against CVD. Under control conditions, TICE accounts for about 30% of fecal cholesterol loss in mice. Using a panel of knock-out and transgenic mice as well as pharmacological manipulations we show that in mice TICE is regulated by intestinal activation of the Farnesoid X Receptor (FXR), via its target Fibroblast Growth Factor 15/19 (FGF15/19). Activation of FXR by the agonist PX20606 (PX) resulted in a >10-fold increased fecal cholesterol excretion as well as TICE and 40% reduced plasma cholesterol levels. The induction of fecal cholesterol excretion and TICE was absent in PX-treated intestine-specific FXR-null mice but was regained when those mice were co-treated with FGF19. Moreover, FGF19 treatment alone was sufficient to induce fecal cholesterol loss to a similar extend as was observed in PX-treated wild-type mice. PX treatment resulted in an increased muricholate/cholate-ratio and thereby induced a more hydrophilic bile salt pool. Not surprisingly, cholesterol absorption was reduced in PX-treated mice. However, experiments in which mice were co-treated with PX and the cholesterol absorption inhibitor ezetimibe revealed that the stimulating effect of PX on fecal neutral sterol excretion and TICE were completely independent of differences in cholesterol absorption. Of note, treatment of mice with a combination of PX and ezetimibe stimulated fecal cholesterol loss and TICE so strongly that those mice lost about 60% of their entire estimated body cholesterol content each day. The stimulation of fecal cholesterol loss and TICE by PX and PX/ezetimibe treatment was severely blunted in Abcg8-KO mice and this could not be restored by hepatic reintroduction of Abcg8, indicating a decisive role for intestinal ABCG5/G8 in PX-induced fecal cholesterol loss and TICE. Our data strongly suggest that hydrophilic bile acids stimulate ABCG5/G8 activity in the intestine, leading to an increased flux of cholesterol from the body into the intestinal lumen that is subsequently excreted with the feces.

Abstract 621: Reduced Dietary Cholesterol Availability in Infancy Programs Cholesterol Absorption in Adult Mice

Epidemiological research showed that feeding breast milk, which is rich in cholesterol, translates into reduced cardiovascular risk in adulthood compared to feeding formula, which is cholesterol free. The mechanisms underlying these observations are unclear. Therefore, the present study aimed to investigate the impact of reduced dietary cholesterol availability during the suckling period on cholesterol metabolism in adult life in mice. To achieve reduced dietary cholesterol exposure from breast milk LDLR knockout offspring were given the cholesterol absorption inhibitor ezetimibe for 3 weeks during the suckling period. Ezetimibe was added to the food of nursing dams and reached the offspring’s intestine via excretion into breast milk. Low cholesterol exposure (LC) mice were compared to normal cholesterol (NC) controls with respect to all relevant parameters of cholesterol metabolism including biliary and fecal cholesterol excretion, intestinal absorption and endogenous synthesis using stable isotope kinetics. At 24 weeks intestinal cholesterol absorption was decreased in LC mice (-30%, p<0.001) due to decreased Npc1l1 expression, the main intestinal cholesterol uptake transporter (-50%, p<0.05). Methylation analysis of the NPC1L1 promoter revealed substantial differences between jejunum and colon (p<0.001), but not between LC and NC. Plasma cholesterol levels were not different between NC and LC due to increased endogenous synthesis in the LC group (p<0.05). Food intake, biliary and fecal cholesterol excretion did not differ between groups. In summary, our results demonstrate that early life reduction of dietary cholesterol exposure programs the murine intestine in adulthood towards decreased cholesterol absorption via reduced Npc1l1 expression. These results support a key role of the intestine as sensor and integrator of cholesterol metabolism with high relevance for cardio-metabolic disease.