A randomized clinical trial examining the impact of LGG probiotic supplementation on psychological status in middle-aged and older adults

In Vitro Development of Enteric-Coated Tablets of the Probiotic Lactobacillus fermentum LF-G89: A Possible Approach to Intestinal Colonization

BACKGROUND

Probiotics must be able to withstand the demanding environment of the gastrointestinal system to adhere to the intestinal epithelium, promoting health benefits. The use of probiotics can prevent or attenuate the effects of dysbiosis that have a deleterious effect on health, promoting anti-inflammatory, immunomodulatory, and antioxidant effects.

OBJECTIVE

The aim of the study was to prepare tablets containing Lactobacillus fermentum LF-G89 coated with 20% Acryl-Eze II® or Opadry® enteric polymers.

METHODS

Tablet dissolution was evaluated under acidic and basic pH conditions, and aliquots of the dissolution medium were plated to count the Colony-forming Units (CFU). The free probiotic's tolerance to pH levels of 1.0, 2.0, 3.0, and 4.0, as well as to pepsin, pancreatin, and bile salts, was assessed.

RESULTS

The probiotic was released from tablets coated after they withstood the pH 1.2 acid stage for 45 minutes. The release was higher with the Acry-Eze II® polymer in the basic stage. The amount of CFU of free probiotics at pH 1.0 to 4.0 as well as pepsin reduced over time, indicating cell death. Conversely, the CFU over time with pancreatin and bile salts increased, demonstrating the resistance of L. fermentum to these conditions due to hydrolases.

CONCLUSION

Both coating polymers were able to withstand the acid step, likely ensuring the release of the probiotic in the small intestine, promoting colonization. Coating with enteric material is a simple and effective process to increase the survival of probiotics, offering a promising alternative to mitigate the negative effects of the dysbiosis process.

Effects of Treatment with Probiotics on Cognitive Function and Regulatory Role of Cortisol and IL-1β in Adolescent Patients with Major Depressive Disorder

The aim of this study was to investigate the effects of probiotics on cognitive function and the regulation of cortisol and IL-1β in adolescents with depression. All 180 participants were randomly assigned to a study group (treated with probiotics combined with sertraline hydrochloride) and a control group (treated with sertraline hydrochloride). The repetitive Neuropsychological State Test (RBANS) and Hamilton Depression Scale (HAMD) were administered to MDD patients. The levels of serum cortisol and IL-1β were detected using an ELISA kit. Except for speech function, factors including immediate memory, visual span, attention function, delayed memory, and the RBANS in the study group were significantly higher than those in the control group. The levels of cortisol and interleukin-1β in the study group were significantly downregulated compared to those in the control group. Except for speech function, the cortisol level was negatively correlated with the RBANS total score and other factors in the study group. Interleukin-1β was also negatively correlated with the RBANS total score and each factor score. Cortisol and interleukin-1β were predictors of the RBANS total score, which explained 46.80% of the variance. Cortisol had significant predictive effects on attention function and delayed memory, and interleukin-1β had significant predictive effects on visual span and speech function. It could be concluded that probiotics could improve cognitive function in adolescents with depression by regulating cortisol and IL-1β levels.

Fish oil and probiotics supplementation through milk chocolate improves spatial learning and memory in male Wistar rats

Background

Cognition and brain function is critical through childhood and should be improved with balanced diets. Incorporating bioactive ingredients such as omega-3 polyunsaturated fatty acids (ω3 PUFAs) and probiotics into food formulations could be used as an approach to improve cognitive function. This study evaluated the effects on cognitive capacity of complementing rodent diets with chocolate, by itself and in combination with ω3 PUFAs from fish oil and probiotics.

Methods

Spatial learning and memory in the rats were determined by the Barnes maze test in short- and long-term memory. Samples from the cecum were obtained to assess microbial counts (Lactobacillus, Bifidobacterium, Enterobacteriaceae, and total bacteria), and brains were recovered to analyze the neural morphology of the tissues. Also, glucose, brain weights, and epididymal tissue were analyzed.

Results

The combination of chocolate with fish oil and probiotics improved the memory of rats compared to the result of each bioactive compound when evaluated separately. Treatments did not affect sugar level, epididymal adipose tissue, or brain weight. On the other hand, consuming probiotics alone or in combination with chocolate decreased Enterobacteria counts, while Lactobacillus and Bifidobacteria counts were not affected. Neural morphological analysis showed that combining chocolate with probiotics and ω3 PUFAs increased the number of neurons in the hippocampal CA1 and CA3 regions.

Conclusion

Chocolate added with probiotics and ω3 PUFAs improved spatial memory and learning in the studied model.

Examining the cognitive benefits of probiotic supplementation in physically active older adults: A randomized clinical trial

The prevalence of dementia is projected to increase with the growing older adult population and prevention strategies are urgently needed. Two promising interventions include physical activity (PA) and probiotic supplementation, with initial findings suggesting their combined use may confer greater cognitive benefits than either intervention alone. However, no study has yet examined the effects of probiotic supplementation on cognitive function in healthy, physically active older adults. The present study used archival data from a randomized clinical trial including 127 physically active, middle-aged to older adults (avg age 64.3 years) with self-reported PA levels meeting or exceeding recommendations to investigate the effects of probiotic supplementation (Lactobacillus rhamnosus GG; L.GG) on cognitive outcomes. Repeated measures ANOVAs showed no significant changes in cognitive performance from baseline to follow up as an effect of L.GG consumption. These results suggest that probiotic supplementation may not improve cognitive function in persons already engaged in high levels of PA. Future research should include prospective studies to determine whether long-term use of probiotic supplementation may help prevent cognitive decline. Novelty: • Initial research shows promising cognitive benefits of combined physical activity and probiotics consumption. • L.GG did not lead to acute cognitive improvements for older adults already meeting physical activity guidelines. • Prospective studies examining prevention of cognitive decline with probiotics in healthy and clinical samples are much needed.

Pressure and Temperature Combined With Microbial Supernatant Effectively Inactivate Bacillus subtilis Spores

Spores from the Bacillus species pose a challenge to the food industry because of their ubiquitous nature and extreme resistance. Accumulated evidence indicates that it is effective to induce spore germination homogenously before killing them. However, it is difficult to obtain and apply exogenous germination factors, which will affect food composition. Therefore, this study screened endogenous germinants from microorganisms by assessing the effect of Escherichia coli, Bacillus subtilis, Saccharomyces cerevisiae, Lactiplantibacillus plantarum, and Streptococcus thermophilus cultures (cell-free) on B. subtilis spore germination. The results showed that the supernatants from these five microorganisms induced spore germination instead of sediments. Moreover, the supernatants of E. coli, B. subtilis, and S. cerevisiae exhibited higher germination rates than L. plantarum and S. thermophilus, and the induction effects were concentration-dependent. Furthermore, plate counting confirmed that the microbial supernatants induced the lowest spore germination ratio on strains B. subtilis FB85 [germination receptors (GRs) mutant] but not strains B. subtilis PB705 (PrkC mutant). In addition, B. subtilis and S. cerevisiae supernatants, combined with pressure and temperature, were effective in spore inactivation. The findings suggested that microbial supernatants may include agents that induce spore germination and may be used for spore inactivation.

Administration of Bifidobacterium breve Improves the Brain Function of Aβ1-42-Treated Mice via the Modulation of the Gut Microbiome

Psychobiotics are used to treat neurological disorders, including mild cognitive impairment (MCI) and Alzheimer's disease (AD). However, the mechanisms underlying their neuroprotective effects remain unclear. Herein, we report that the administration of bifidobacteria in an AD mouse model improved behavioral abnormalities and modulated gut dysbiosis. Bifidobacterium breve CCFM1025 and WX treatment significantly improved synaptic plasticity and increased the concentrations of brain-derived neurotrophic factor (BDNF), fibronectin type III domain-containing protein 5 (FNDC5), and postsynaptic density protein 95 (PSD-95). Furthermore, the microbiome and metabolomic profiles of mice indicate that specific bacterial taxa and their metabolites correlate with AD-associated behaviors, suggesting that the gut-brain axis contributes to the pathophysiology of AD. Overall, these findings reveal that B. breve CCFM1025 and WX have beneficial effects on cognition via the modulation of the gut microbiome, and thus represent a novel probiotic dietary intervention for delaying the progression of AD.

Probiotic Lactobacillus fermentum strain JDFM216 improves cognitive behavior and modulates immune response with gut microbiota

Increasing evidence indicates that alterations in gut microbiota are associated with mammalian development and physiology. The gut microbiota has been proposed as an essential player in metabolic diseases including brain health. This study aimed to determine the impact of probiotics on degenerative changes in the gut microbiota and cognitive behavior. Assessment of various behavioral and physiological functions was performed using Y-maze tests, wheel running tests, accelerated rotarod tests, balance beam tests, and forced swimming tests (FSTs), using adult mice after 50 weeks of administering living probiotic bacterium Lactobacillus fermentum strain JDFM216 or a vehicle. Immunomodulatory function was investigated using immune organs, immune cells and immune molecules in the mice, and gut microbiota was also evaluated in their feces. Notably, the L. fermentum JDFM216-treated group showed significantly better performance in the behavior tests (P < 0.05) as well as improved phagocytic activity of macrophages, enhanced sIgA production, and stimulated immune cells (P < 0.05). In aged mice, we observed decreases in species belonging to the Porphyromonadaceae family and the Lactobacillus genus when compared to young mice. While administering the supplementation of L. fermentum JDFM216 to aged mice did not shift the whole gut microbiota, the abundance of Lactobacillus species was significantly increased (P < 0.05). Our findings suggested that L. fermentum JDFM216 also provided beneficial effects on the regulation of immune responses, which has promising implications for functional foods. Taken together, L. fermentum JDFM216 could confer the benefit of improving health with enhanced cognition, physiological behavior, and immunity by modulating the gut microbiota.

Randomized Clinical Trial Examining the Impact of Lactobacillus rhamnosus GG Probiotic Supplementation on Cognitive Functioning in Middle-aged and Older Adults

PURPOSE

The gut microbiome has been linked to cognitive function and appears to worsen with aging. Probiotic supplementation has been found to improve the health of the gut microbiome. As such, it is possible that probiotic supplementation may protect the aging brain. The current study examined the cognitive benefits of probiotic supplementation (Lactobacillus rhamnosus GG) in healthy middle-aged and older adults.

MATERIALS AND METHODS

The study was a double-blind, placebo-controlled, randomized clinical trial. Two hundred community-dwelling adults aged 52-75 were enrolled (mean age=64.3, SD=5.52). A three-month intervention involved daily consumption of probiotic or placebo. Independent sample t-tests, chi-squared tests, and repeated measure ANOVAs compared groups and examined changes over time. Primary outcome was change in NIH Toolbox Total Cognition Score from baseline to follow-up.

RESULTS

A total of 145 participants were examined in primary analyses (probiotic=77, placebo=68) and excluded persons due to discontinuation, low adherence, missing data, or outlier values. Established criteria (ie ≥1 subtest t-scores ≤35; n=19, n=23) were used to operationally define cognitive impairment. Repeated measures ANOVAs revealed that persons with cognitive impairment who consumed probiotics exhibited a greater total cognition score improvement than persons with cognitive impairment in the placebo group and cognitively intact persons in probiotic or placebo groups.

CONCLUSION

Lactobacillus rhamnosus GG probiotic supplementation was associated with improved cognitive performance in middle-aged and older adults with cognitive impairment. Probiotic supplementation may be a novel method for protecting cognitive health in aging.

Probiomimetics-Novel Lactobacillus-Mimicking Microparticles Show Anti-Inflammatory and Barrier-Protecting Effects in Gastrointestinal Models

There is a lack of efficient therapies to treat increasingly prevalent autoimmune diseases, such as inflammatory bowel disease and celiac disease. Membrane vesicles (MVs) isolated from probiotic bacteria have shown tremendous potential for treating intestinal inflammatory diseases. However, possible dilution effects and rapid elimination in the gastrointestinal tract may impair their application. A cell-free and anti-inflammatory therapeutic system-probiomimetics-based on MVs of probiotic bacteria (Lactobacillus casei and Lactobacillus plantarum) coupled to the surface of microparticles is developed. The MVs are isolated and characterized for size and protein content. MV morphology is determined using cryoelectron microscopy and is reported for the first time in this study. MVs are nontoxic against macrophage-like dTHP-1 and enterocyte-like Caco-2 cell lines. Subsequently, the MVs are coupled onto the surface of microparticles according to facile aldehyde-group functionalization to obtain probiomimetics. A significant reduction in proinflammatory TNF-α level (by 86%) is observed with probiomimetics but not with native MVs. Moreover, it is demonstrated that probiomimetics have the ability to ameliorate inflammation-induced loss of intestinal barrier function, indicating their potential for further development into an anti-inflammatory formulation. These engineered simple probiomimetics that elicit striking anti-inflammatory effects are a key step toward therapeutic MV translation.

Lactobacillus rhamnosus GG and HbA1c in middle age and older adults without type 2 diabetes mellitus: A preliminary randomized study

BACKGROUND AND AIMS

Probiotic supplementation improves glycemic control in persons with diabetes and the current study examined whether these benefits extend to healthy individuals.

METHODS

The current study was a 90-day placebo-controlled, double-blind, randomized clinical trial of Lactobacillus rhamnosus GG in healthy middle-aged and older adults. Fasting blood glucose and HbA1c were quantified at baseline and follow up.

RESULTS

ANCOVA controlling for baseline values showed group differences in follow up HbA1c [F (1,90) = 8.44, p = 0.005]; HbA1c values increased in the placebo group, though remained stable in the probiotic group.

CONCLUSIONS

If replicated, Lactobacillus rhamnosus GG may protect against changes in glycemic control.

Relationship between dementia and gut microbiome-associated metabolites: a cross-sectional study in Japan

Dysregulation of the gut microbiome is associated with dementia. However, the relationship between microbiome-associated metabolites and dementia has yet to be identified. Outpatients visiting a memory clinic in Japan enrolled in this cross-sectional study; 107 subjects were eligible for the study, 25 of which had dementia. We collected demographics, activities of daily living, risk factors, cognitive function, and brain imaging data. The gut microbiome was assessed using terminal restriction fragment length polymorphism analysis. Concentrations of faecal metabolite were measured. We used multivariable logistic regression analyses to identify whether metabolites were independently related to dementia. The concentrations of metabolites were significantly different between subjects with and those without dementia. Every 1 standard deviation increment in faecal ammonia concentration was associated with around a 1.6-fold risk for the presence of dementia. A higher faecal lactic acid concentration was related to a lower risk of dementia, by around 60%. A combination of higher faecal ammonia and lactic acid concentrations was indicative of the presence of dementia, and had a similar predictive value as traditional biomarkers of dementia. Thus, faecal ammonia and lactic acid are related to dementia, independently of the other risk factors for dementia and dysregulation of the gut microbiome.

Pharmacological signatures of the reduced incidence and the progression of cognitive decline in ageing populations suggest the protective role of beneficial polypharmacy

Preventive treatments for dementia are warranted. Here we show that utilization of certain combinations of prescription medications and supplements correlates with reduced rates of cognitive decline. More than 1,900 FDA-approved agents and supplements were collapsed into 53 mechanism-based groups and traced in electronic medical records (EMRs) for >50,000 patients. These mechanistic groups were aligned with the data presented in more than 300 clinical trials, then regression model was built to fit the signals from EMRs to clinical trial performance. While EMR signals of each single agents correlated with clinical performance relatively weakly, the signals produced by combinations of active compounds were highly correlated with the clinical trial performance (R = 0.93, p = 3.8 x10^-8). Higher ranking pharmacological modalities were traced in patient profiles as their combinations, producing protective complexity estimates reflecting degrees of exposure to beneficial polypharmacy. For each age strata, the higher was the protective complexity score, the lower was the prevalence of dementia, with maximized life-long effects for the highest regression score /diversity compositions. The connection was less strong in individuals already diagnosed with cognitive impairment. Confounder analysis confirmed an independent effect of protective complexity in multivariate context. A sub-cohort with lifelong odds of dementia decreased > 5-folds was identified; this sub-cohort should be studied in further details, including controlled clinical trials. In short, our study systematically explored combinatorial preventive treatment regimens for age-associated multi-morbidity, with an emphasis on neurodegeneration, and provided extensive evidence for their feasibility.

The effects of medication adherence on study outcomes in randomized clinical trials: A role for cognitive dysfunction?

Medication nonadherence is common and has been associated with poor health outcomes. Older adults are especially likely to be non-adherent to their medications, as they often have more medications to manage and are at greater risk for cognitive dysfunction. Though less frequently examined, the association between cognitive dysfunction and nonadherence also likely extends to clinical trials research. The current study used archival data to examine the potential impact of cognitive dysfunction on adherence to a nutritional supplement as part of a 90-day randomized clinical trial in neurologically healthy middle-aged and older adults. Results showed overall cognitive performance was predictive of adherence to capsule intake when controlling for polypharmacy [F(1,157) = 6.53, p < .01]. These results suggest that cognitive dysfunction may impact findings from RCTs through its adverse impact on adherence to study protocol, possibly leading to greater treatment variance, artificially reduced treatment effects, lower study power, and distorted study outcomes and conclusions. A better understanding of methodological and statistical approaches to account for these unwanted effects are needed.

Microbiome Influence in the Pathogenesis of Prion and Alzheimer's Diseases

Misfolded and abnormal β-sheets forms of wild-type proteins, such as cellular prion protein (PrPC) and amyloid beta (Aβ), are believed to be the vectors of neurodegenerative diseases, prion and Alzheimer's disease (AD), respectively. Increasing evidence highlights the "prion-like" seeding of protein aggregates as a mechanism for pathological spread in AD, tauopathy, as well as in other neurodegenerative diseases, such as Parkinson's. Mutations in both PrPC and Aβ precursor protein (APP), have been associated with the pathogenesis of these fatal disorders with clear evidence for their pathogenic significance. In addition, a critical role for the gut microbiota is emerging; indeed, as a consequence of gut-brain axis alterations, the gut microbiota has been involved in the regulation of Aβ production in AD and, through the microglial inflammation, in the amyloid fibril formation, in prion diseases. Here, we aim to review the role of microbiome ("the other human genome") alterations in AD and prion disease pathogenesis.