Prebiotic Effect of Berberine and Curcumin Is Associated with the Improvement of Obesity in Mice

Berberine and curcumin, used as food additives or food supplements, possess interesting anti-inflammatory and antioxidant properties. We tested the potential protective effect of both phytochemicals in genetically obese mice and we determined whether these effects can be related to the modulation of gut functions and microbiota. Ob/ob mice were fed a standard diet supplemented with or without 0.1% berberine and/or 0.3% curcumin for 4 weeks. By using targeted qPCR, we found that cecal content of Bifidobacterium spp. and Akkermansia spp. increased mainly upon berberine supplementation. Genes involved in innate immunity (Pla2g2a), mucus production (Muc2) and satietogenic peptide production (Gcg and Pyy) were upregulated in the colon of mice treated with both phytochemicals. Berberine supplementation alone reduced food intake, body weight gain, hypertriglyceridemia and hepatic inflammatory and oxidative stress markers, thus lessening hepatic injury. The increase in Bifidobacterium spp. and Akkermansia spp. was correlated with the improvement of gut barrier function and with the improvement of hepatic inflammatory and oxidative stresses in obese mice. These data support the fact that non-carbohydrate phytochemicals may modulate the gut microbiota in obesity and related gut and hepatic alterations.

Prebiotic dietary fibre intervention improves fecal markers related to inflammation in obese patients: results from the Food4Gut randomized placebo-controlled trial

Purpose

Inulin-type fructans (ITF) are prebiotic dietary fibre (DF) that may confer beneficial health effects, by interacting with the gut microbiota. We have tested the hypothesis that a dietary intervention promoting inulin intake versus placebo influences fecal microbial-derived metabolites and markers related to gut integrity and inflammation in obese patients.

Methods

Microbiota (16S rRNA sequencing), long- and short-chain fatty acids (LCFA, SCFA), bile acids, zonulin, and calprotectin were analyzed in fecal samples obtained from obese patients included in a randomized, placebo-controlled trial. Participants received either 16 g/d native inulin (prebiotic n = 12) versus maltodextrin (placebo n = 12), coupled to dietary advice to consume inulin-rich versus inulin-poor vegetables for 3 months, in addition to dietary caloric restriction.

Results

Both placebo and prebiotic interventions lowered energy and protein intake. A substantial increase in Bifidobacterium was detected after ITF treatment (q = 0.049) supporting our recent data obtained in a larger cohort. Interestingly, fecal calprotectin, a marker of gut inflammation, was reduced upon ITF treatment. Both prebiotic and placebo interventions increased the ratio of tauro-conjugated/free bile acids in feces. Prebiotic treatment did not significantly modify fecal SCFA content but it increased fecal rumenic acid, a conjugated linoleic acid (cis-9, trans-11 CLA) with immunomodulatory properties, that correlated notably to the expansion of Bifidobacterium (p = 0.031; r = 0.052).

Conclusions

Our study demonstrates that ITF-prebiotic intake during 3 months decreases a fecal marker of intestinal inflammation in obese patients. Our data point to a potential contribution of microbial lipid-derived metabolites in gastro-intestinal dysfunction related to obesity.

ClinicalTrials.gov Identifier

NCT03852069 (February 22, 2019 retrospectively, registered).

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-021-02484-5.

Metabolite profiling reveals the interaction of chitin-glucan with the gut microbiota

Dietary fibers are considered beneficial nutrients for health. Current data suggest that their interaction with the gut microbiota largely contributes to their physiological effects. In this context, chitin-glucan (CG) improves metabolic disorders associated with obesity in mice, but its effect on gut microbiota has never been evaluated in humans. This study explores the effect of a 3-week intervention with CG supplementation in healthy individuals on gut microbiota composition and bacterial metabolites. CG was given to healthy volunteers (n = 15) for three weeks as a supplement (4.5 g/day). Food diary, visual analog and Bristol stool form scales and a "quality of life" survey were analyzed. Among gut microbiota-derived metabolites, bile acids (BA), long- and short-chain fatty acids (LCFA, SCFA) profiling were assessed in stool samples. The gut microbiota (primary outcome) was analyzed by Illumina sequencing. A 3-week supplementation with CG is well tolerated in healthy humans. CG induces specific changes in the gut microbiota composition, with Eubacterium, Dorea and Roseburia genera showing the strongest regulation. In addition, CG increased bacterial metabolites in feces including butyric, iso-valeric, caproic and vaccenic acids. No major changes were observed for the fecal BA profile following CG intervention. In summary, our work reveals new potential bacterial genera and gut microbiota-derived metabolites characterizing the interaction between an insoluble dietary fiber -CG- and the gut microbiota.

Venom from two sub-species of Heloderma horridum (Mexican beaded lizard): general characterization and purification of N-benzoyl-L-arginine ethyl ester hydrolase

The venom from the lizards Heloderma horridum horridum and Heloderma horridum alvarezi was obtained at a protein concentration of 80 mg/ml with a pH value of 6.9-7.0. The volume of venom obtained is approximately 0.5 ml per extraction. The i.p. LD50 value in mice for both sub-species is 2 mg/kg body weight. The electrophoretic pattern of the venom applied to polyacrylamide gels shows at least 18 protein bands and this pattern is constant for the same animal during all 12 months of the year, although different animals from the same population may present a slightly different pattern. The venom has the following enzymatic activities: phospholipase A, hyaluronidase, and Bz-Arg-OEt and Bz-Tyr-OEt hydrolase. Some of the venom components can be selectively and reversibly precipitated at acidic pH (4.7). The venom is very immunogenic and the sheep anti-sera against both sub-species cross-react quite extensively. A Bz-Arg-OEt hydrolase was purified from the venom of H. h. horridum by column chromatography in Sephadex G-75 followed by two steps on DEAE-cellulose columns at two different pH values (7.55 and 8.6). The last step was chromatography in a phenyl-sepharose column. The molecular weight of this enzyme, as obtained by SDS-gel electrophoresis, is approx. 65,000.