Effect of gut microbiome modulation on muscle function and cognition: the PROMOTe randomised controlled trial

Studies suggest that inducing gut microbiota changes may alter both muscle physiology and cognitive behaviour. Gut microbiota may play a role in both anabolic resistance of older muscle, and cognition. In this placebo controlled double blinded randomised controlled trial of 36 twin pairs (72 individuals), aged ≥60, each twin pair are block randomised to receive either placebo or prebiotic daily for 12 weeks. Resistance exercise and branched chain amino acid (BCAA) supplementation is prescribed to all participants. Outcomes are physical function and cognition. The trial is carried out remotely using video visits, online questionnaires and cognitive testing, and posting of equipment and biological samples. The prebiotic supplement is well tolerated and results in a changed gut microbiome [e.g., increased relative Bifidobacterium abundance]. There is no significant difference between prebiotic and placebo for the primary outcome of chair rise time (β = 0.579; 95% CI −1.080-2.239 p = 0.494). The prebiotic improves cognition (factor score versus placebo (β = −0.482; 95% CI,−0.813, −0.141; p = 0.014)). Our results demonstrate that cheap and readily available gut microbiome interventions may improve cognition in our ageing population. We illustrate the feasibility of remotely delivered trials for older people, which could reduce under-representation of older people in clinical trials. ClinicalTrials.gov registration: NCT04309292

10 PW Peak Power Laser at the Extreme Light Infrastructure Nuclear Physics – status updates

We have shown, for the first time in the world, the production of 10 PW peak power laser pulses and their propagation to an experimental area at the Extreme Light Infrastructure - Nuclear Physics (ELI-NP). We are also steadily running the laser system for experimental campaigns, increasing the output power levels delivered for experiments and fine-tuning the parameters of the laser pulses, the operational procedures, and the operational teams. During our presentation, we will show the laser developments at ELI-NP emphasizing the 10 PW peak power demonstrations and the latest results for the HPLS beam delivery

A faecal metabolite signature of impaired fasting glucose: results from two independent population-based cohorts

Prediabetes is a metabolic condition associated with gut microbiome composition, though mechanisms remain elusive. We searched for faecal metabolites, a readout of gut microbiome function, associated with impaired fasting glucose (IFG) in 142 individuals with IFG and 1105 healthy individuals from TwinsUK. We used the KORA cohort (318 IFG individuals, 689 healthy individuals) to replicate our findings. We linearly combined 8 IFG-positively associated metabolites (1-methylxantine, nicotinate, glucuronate, uridine, cholesterol, serine, caffeine and protoporphyrin IX) into an IFG-metabolite score, which was significantly associated with higher odds ratios for IFG (TwinsUK: OR[95%CI]=3.9[3.02-5.02], p<0.0001, KORA: OR[95%CI]=1.3[1.16-1.52], p<0.0001) and incident type-2 diabetes (T2D) (TwinsUK: HR[95%CI]=4[1.97-8], p=0.0002). Although these are host-produced metabolites, we found that the gut microbiome is strongly associated with their faecal levels (AUC>70%). Abundances of Faecalibacillus intestinalis, Dorea formicigenerans, Ruminococcus torques and Dorea sp. AF24_7LB were positively associated with IFG, and such associations were partially mediated by 1-methylxanthine and nicotinate (VAF mean(SD)=14.4%(5.1), p<0.05). Our results suggest that gut microbiome is linked to prediabetes not only via the production of microbial metabolites but also by affecting intestinal absorption/excretion of host-produced metabolites and xenobiotics, which are correlated with the risk of IFG. Faecal metabolites enable modelling of another mechanism of gut microbiome effect on prediabetes and T2D onset

Genetic and gut microbiome determinants of SCFA circulating and fecal levels, postprandial responses and links to chronic and acute inflammation

ABSTRACTShort-chain fatty acids (SCFA) are involved in immune system and inflammatory responses. We comprehensively assessed the host genetic and gut microbial contribution to a panel of eight serum and stool SCFAs in two cohorts (TwinsUK, n = 2507; ZOE PREDICT-1, n = 328), examined their postprandial changes and explored their links with chronic and acute inflammatory responses in healthy individuals and trauma patients. We report low concordance between circulating and fecal SCFAs, significant postprandial changes in most circulating SCFAs, and a heritable genetic component (average h2: serum = 14%(SD = 14%); stool = 12%(SD = 6%)). Furthermore, we find that gut microbiome can accurately predict their fecal levels (AUC>0.71) while presenting weaker associations with serum. Finally, we report different correlation patterns with inflammatory markers depending on the type of inflammatory response (chronic or acute trauma). Our results illustrate the breadth of the physiological relevance of SCFAs on human inflammatory and metabolic responses highlighting the need for a deeper understanding of this important class of molecules

The secondary bile acid isoursodeoxycholate correlates with post-prandial lipemia, inflammation, and appetite and changes post-bariatric surgery

Primary and secondary bile acids (BAs) influence metabolism and inflammation, and the gut microbiome modulates levels of BAs. We systematically explore the host genetic, gut microbial, and habitual dietary contribution to a panel of 19 serum and 15 stool BAs in two population-based cohorts (TwinsUK, n = 2,382; ZOE PREDICT-1, n = 327) and assess changes post-bariatric surgery and after nutritional interventions. We report that BAs have a moderately heritable genetic component, and the gut microbiome accurately predicts their levels in serum and stool. The secondary BA isoursodeoxycholate (isoUDCA) can be explained mostly by gut microbes (area under the receiver operating characteristic curve [AUC] = ∼80%) and associates with post-prandial lipemia and inflammation (GlycA). Furthermore, circulating isoUDCA decreases significantly 1 year after bariatric surgery (β = −0.72, p = 1 × 10−5) and in response to fiber supplementation (β = −0.37, p < 0.03) but not omega-3 supplementation. In healthy individuals, isoUDCA fasting levels correlate with pre-meal appetite (p < 1 × 10−4). Our findings indicate an important role for isoUDCA in lipid metabolism, appetite, and, potentially, cardiometabolic risk