Effects of long-term administration of Lactobacillus reuteri DSM-17938 on circulating levels of 5-HT and BDNF in adults with functional constipation

Accumulated evidence shows that some probiotic strains ameliorate functional constipation (FC) via the modulation of specific gastrointestinal peptide pathways. The aims of this study were to investigate: (1) the effects of long-term administration of Lactobacillus reuteri (LR) DSM 17938 on the serum levels of serotonin (5-HT) and brain-derived neurotrophic factor (BDNF); (2) the possible link between 5-HT, BDNF, and specific constipation-related symptoms; (3) whether genetic variability at the 5-HTT gene-linked polymorphic region (5-HTTLPR) and BDNF Val66Met loci could be associated with serum 5-HT and BDNF variations. LR DSM 17938 was administered to 56 FC patients for 105 days in a randomised, double-blind manner. The fasting blood samples were collected during the randomisation visit (V₁), at day 15 (induction period, V₂), day 60 (intermediate evaluation, V₃), and day 105 (V₄) and the Constipaq questionnaire (the sum of Constipation Scoring System (CSS) and patient assessment constipation quality of life (PAC-QoL)) was administered. A group of healthy subjects was enrolled as controls (HC). At V1, the mean serum 5-HT level in the whole patient group was significantly higher (P=0.027) than in HC subjects, while serum BDNF did not. At the end of probiotic administration (V4), 5-HT and BDNF levels were significantly lower than the initial values (V1) (P=0.008 and P=0.015, respectively). 5-HT and BDNF serum concentration were significantly associated (r=0.355; P=0.007). Neither 5-HT nor BDNF serum levels correlated with the CSS item scores and with the PAC-QoL. Lastly, the regression analysis demonstrated that the presence of the S allele of the 5-HTTLPR accounted for the reduction in the 5-HT concentration at V4. In conclusion, the long-term administration of LR DSM 17938 demonstrated that such a probiotic strain could improve FC by affecting 5-HT and BDNF serum concentrations.

Randomised clinical trial: efficacy of Lactobacillus paracasei-enriched artichokes in the treatment of patients with functional constipation--a double-blind, controlled, crossover study

BACKGROUND

The role of probiotics in the management of constipation is uncertain.

AIMS

To evaluate the effects of probiotic-enriched artichokes on treatment preference, symptom profile and short-chain fatty acid (SCFA) production in constipated subjects when compared with ordinary artichokes.

METHODS

Twenty constipated patients (3M/17F; 38.8 ± 14.4 years) were studied using a double-blind method and a computer-generated randomisation list. Each patient consumed 180 g per day of ordinary artichokes or artichokes enriched with Lactobacillus paracasei IMPC 2.1 for 15 days (daily dose of 2 × 10(10) CFU). Relief of symptoms was evaluated using a visual analogue scale. The stool consistency and symptom profile of patients were investigated using the Bristol stool form chart and the Gastrointestinal Symptom Rating Scale questionnaire (GSRS). SCFA production in faecal samples was evaluated using HPLC.

RESULTS

Eighty per cent of patients preferred probiotic-enriched artichokes to ordinary ones (P = 0.011). Satisfactory relief of symptoms was significantly higher (P = 0.0014) during the probiotic-enriched artichoke period. Bristol chart cluster scores were significantly higher (3.3 ± 1.2, 2.9 ± 1.3 2.2 ± 1.2, baseline, ordinary artichokes and probiotic-enriched ones, respectively; P = 0.009) and GSRS constipation was significantly lower (13.9 ± 0.9, 10.2 ± 0.8, 8.3 ± 0.9; P = 0.032) in the probiotic group compared with the baseline. As for SCFA production, propionic acid was significantly higher (2.2 ± 1.4, 2.1 ± 1.53, 1.5 ± 1.2; P = 0.035) in the probiotic group compared with baseline.

CONCLUSION

This trial shows a positive effect on symptoms in constipated patients after intake of probiotic-enriched artichokes.

Metabolic effects of a diet with inulin-enriched pasta in healthy young volunteers

Different lines of evidence suggest that higher intake of fiber may somehow protect against metabolic syndrome. The prebiotic inulin has widely been studied in relation to its putative beneficial effects on lipid and glucose metabolism. Therefore, adding inulin to diet may be a suitable strategy to prevent metabolic syndrome. Aim of the present study was to evaluate the effects of the daily consumption of inulin-enriched pasta on lipid and glucose metabolism as well as on gastrointestinal motility in young healthy subjects. Methods. Twenty-two healthy young male volunteers entered a randomized double blind cross-over study consisting of a 2-weeks a run-in period, two 5-weeks study periods (11% inulin-enriched or control pasta), and an 8-weeks wash-out period in between. Serum lipid and glucose concentrations were evaluated by routine biochemical analyses. Gastric emptying time and electrical activity were non-invasively evaluated by ultrasound and electrogastrography. Data were analyzed by Friedman Repeated Measures ANOVA test. Results. Significant differences among baseline and the treatment group were found for HDL-cholesterol (p=0.004), total cholesterol/HDL-cholesterol ratio (p=0.006), triglycerides (p=0.04), fasting glucose level (p=0.044), fructosamine (p=0.0478), HbA1c (p=0.04), and homeostatic model assessment (HOMA-IR) (p=0.045). The gastric emptying, expressed as final emptying time, was found significantly delayed in the group that assumed inulin-enriched pasta (p=0.008). Conclusions. Inulin-enriched pasta improved lipidic and glicidic metabolism as well as the insulin resistance in healthy young subjects. In addition, it delayed the gastric emptying time which may represent the physiological counterpart of its metabolic effects.

Antioxidant effect of short-term hormonal treatment in postmenopausal women

OBJECTIVES

Recent studies have shown that estrogens alone or in association with progestins can exert an antioxidant effect on Low-Density Lipoprotein (LDL) and lipids of platelet membranes. It has been demonstrated that the oxidative modification of LDLs also involving the formation of lipid peroxides, exerts several biological effects that may contribute to the onset and progression of cardiovascular diseases. Therefore, the aim of our study was to evaluate the effect of short-term treatment with oral estrogens alone and estrogens plus progestin on endogenous and copper-induced serum levels of lipid peroxides in postmenopausal women.

METHODS

Thirty-nine postmenopausal women were randomly divided into three groups: group I was treated with oral conjugated equine estrogens (CEE) for 21 days; group II received oral CEE for 21 days and, after 14 days of this treatment, 5 mg/day of medrogestone was added for 7 days; group III did not receive any therapy (controls). Endogenous and copper-induced serum levels of lipid peroxides were determined before and after 21 days of treatment in the two treated groups and in the control group.

RESULTS

The serum endogenous levels of lipid peroxides in postmenopausal women did not change after short-term treatment with hormone replacement therapy. Moreover, copper-induced serum levels of lipid peroxides significantly decreased after therapy in both groups I and II.

CONCLUSIONS

Our data show that hormone replacement therapy (HRT) inhibits lipid peroxidation and may play a role in preventing cardiovascular diseases.