Treatment with Anaerobutyricum soehngenii: a pilot study of safety and dose-response effects on glucose metabolism in human subjects with metabolic syndrome.

Dysbiosis of the intestinal microbiota has been implicated in insulin resistance, although evidence regarding causality in humans is scarce. We performed a phase I/II dose-finding and safety study on the effect of oral intake of the anaerobic butyrogenic strain Anaerobutyricum soehngenii on glucose metabolism in 24 subjects with metabolic syndrome. We found that treatment with A. soehngenii was safe and observed a significant correlation between the measured fecal abundance of administered A. soehngenii and improvement in peripheral insulin sensitivity after 4 weeks of treatment. This was accompanied by an altered microbiota composition and a change in bile acid metabolism. Finally, we show that metabolic response upon administration of A. soehngenii (defined as improved insulin sensitivity 4 weeks after A. soehngenii intake) is dependent on microbiota composition at baseline. These data in humans are promising, but additional studies are needed to reproduce our findings and to investigate long-term effects, as well as other modes of delivery.

HDL protein composition alters from proatherogenic into less atherogenic and proinflammatory in rheumatoid arthritis patients responding to rituximab.

OBJECTIVE: An atherogenic lipid profile is an established risk factor for cardiovascular (CV) diseases. Interestingly, high inflammatory states as present in rheumatoid arthritis (RA) are associated with unfavourable lipid profile. Data about effects of novel immunomodulating agents as rituximab (RTX) on lipid profile are limited. Therefore, changes in lipids in RTX treated RA patients were evaluated. METHODS: In 49 consecutive RTX treated RA patients, serum and EDTA plasma samples were collected at baseline, 1, 3 and 6 months. In these samples, lipid and levels were assessed to determine changes in time. Surface-enhanced laser desorption/ionisation time-of-flight (SELDI-TOF) MS analysis was performed in six good and six non-responding RA patients to study functional high density lipoprotein (HDL) protein composition changes in time. RESULTS: In the total group (n=49), the atherogenic index decreased from 4.3 to 3.9 (∼9%) after 6 months. Testing for effect modification revealed a difference in the effect on lipid levels between responders and non-responders upon RTX (p<0.001). ApoB to ApoA-I ratios decreased significantly (∼9%) in good responding (n=32) patients. SELDI-TOF MS analysis revealed a significant decrease in density of mass charge (m/z) marker 11743, representing a decrease in serum amyloid A, in good responding patients. CONCLUSION: This study indicates beneficial effects on cholesterol profile upon RTX treatment along with improvement of disease activity. Proteomic analysis of the HDL particle reveals composition changes from proatherogenic to a less proatherogenic composition during 6 months RTX treatment. Whether these HDL particle alterations during immunotherapies result in a lower CV event rate remains to be established.