Clinical and metabolic response to probiotic supplementation in patients with multiple sclerosis: A randomized, double-blind, placebo-controlled trial. Clin Nutr. 2017;36:1245-1249. [PMID: 27669638 DOI: 10.1016/j.clnu.2016.08.015]

The effects of probiotic Saccharomyces boulardii on the mental health, quality of life, fatigue, pain, and indices of inflammation and oxidative stress in patients with multiple sclerosis: study protocol for a double-blind randomized controlled clinical trial

BACKGROUND

The relationship between gut dysbiosis and inflammatory diseases including multiple sclerosis (MS) is presently recognized as an important health issue. It has been established that some bacterial probiotic strains are effective in treating MS. This study will investigate the effect of yeast probiotic Saccharomyces boulardii (SB) supplements on mental health, quality of life, fatigue, pain, and indices of inflammation and oxidative stress in MS patients.

METHODS/DESIGN

In this double-blind randomized controlled two-group parallel trial, 50 MS patients who meet the inclusion criteria will be recruited from outpatient settings. They will be randomly allocated to 4 months of daily placebo or the SB probiotic intervention. Blood samples will be taken from each participant at the baseline and after the intervention period to assess inflammation and oxidative stress. The primary endpoint will be the changes in their mental health evaluated by the 28-item General Health Questionnaire. The secondary endpoints include changes in: (1) quality of life, evaluated by the 36-item Short Form Questionnaire, (2) fatigue, evaluated by the Fatigue Severity Scale, (3) pain, evaluated by a visual analogue scale, and (4) serum levels of indices of inflammatory stress (high-sensitivity C-reactive protein) and oxidative stress (malondialdehyde and total antioxidant capacity). Moreover, any adverse events and side effects due to the intervention will be documented.

DISCUSSION

There is a need to discover safe and practical methods for managing the symptoms of MS. This trial will gather evidence on the effects of a probiotic.

TRIAL REGISTRATION

Iranian Clinical Trial Registry, IRCT20161022030424N1 . Registered on 9 April 2018.

An introduction of the role of probiotics in human infections and autoimmune diseases

During the last decades, studies exploring the role of microorganisms inhabiting human body in different scenarios have demonstrated the great potential of modulating them to treat and prevent diseases. Among the most outstanding applications, probiotics have been used for over a century to treat infections and inflammation. Despite the beneficial role of other probiotics, Lactobacillus and Bifidobacterium species are the most frequently used, and have been effective as a therapeutic option in the treatment/prevention of dental caries, periodontal diseases, urogenital infections, and gastrointestinal infections. Additionally, as gastrointestinal tract harbors a great diversity of microbial species that directly or indirectly modulate host metabolism and immune response, the influence of intestinal microbiota, one of the targets of therapies using probiotics, on the biology of immune cells can be explored to treat inflammatory disorders or immune-mediated diseases. Thus, it is not surprising that probiotics have presented promising results in modulating human inflammatory diseases such as type 1 diabetes, multiple sclerosis, rheumatoid arthritis and inflammatory bowel disease, among others. Hence, the purpose of this review is to discuss the potential of therapeutic approaches using probiotics to constrain infection and development of inflammation on human subjects.

Effect of probiotic supplementation on seizure activity and cognitive performance in PTZ-induced chemical kindling

Epilepsy is one of the most common neurological disorders that severely affect life quality of many people worldwide. Ion transport in the neuronal membrane, inhibitory-excitatory mechanisms, and regulatory modulator systems have been implicated in the pathogenesis of epilepsy. A bidirectional communication is proposed between brain and gut where the brain modulates the gastrointestinal tract, and the gut can affect brain function and behavior. The gut microbiome takes an important role in health and disease where dysbiosis is involved in several neurological disorders. Probiotics as living microorganisms are beneficial to humans and animals when adequately administered. In the present work, we evaluated the effect of a probiotic bacteria mixture on seizure activity, cognitive function, and gamma-aminobutyric acid (GABA), nitric oxide (NO), malondealdehyde (MDA), and total antioxidant capacity (TAC) level of the brain tissue in the pentylenetetrazole (PTZ)-induced kindled rats. The Racine score and performance in water maze were considered as indices of the epileptic severity and the spatial learning and memory, respectively. We found that the probiotic supplementation substantially reduces seizure severity so that almost no probiotic-treated animals showed full kindling. The oral bacteriotherapy partially improved the spatial learning and memory in the kindled rats. The intervention decreased NO and MDA and increased TAC concentration of the brain. The probiotic treatment also increased the inhibitory neurotransmitter GABA. Our findings are the first preclinical report to show positive effect of probiotic bacteria on seizure-induced neurological disorders. Further investigation is required to answer the questions raised about the probable mechanisms involved.

Effect of probiotic and synbiotic supplementation on inflammatory markers in health and disease status: A systematic review and meta-analysis of clinical trials

The current systematic review and meta-analysis investigated the effect of probiotic/synbiotic on a wide range of inflammatory and anti-inflammatory markers in healthy and various disease conditions. PubMed, SCOPUS and Web of Science databases were searched. All clinical trials which investigated the effect of oral administration of probiotic or synbiotic on inflammatory markers (C-reactive protein (CRP), interleukin (IL) 1β, IL-4, IL-6, IL-8, IL-10, IL-12, tumor necrosis factor (TNF) α, interferon (IFN) γ and transforming growth factor (TGF) β) for more than one week with concurrent control groups were included. One-hundred sixty seven publications was analysed. Results were as follows: CRP decreased in healthy, metabolic disorders, inflammatory bowel disease (IBD), arthritis and critically ill condition but not in renal failure. IL-1B: no change in healthy subjects and arthritis. TNF-α: decreased in healthy, fatty liver, IBD and hepatic cirrhosis, no change in diabetes, metabolic syndrome (MS) + PCOS (polycystic ovary syndrome) and arthritis. IL-6: no change in healthy, metabolic disorders and arthritis, increased in cirrhosis and renal failure, decreased in PCOS + MS. IL-10: no change in healthy, IBD and metabolic disorders, increased in arthritis. IL-4, IL-8, IL-12, IFN-g and TGF-b: no change in healthy subjects. In conclusion, probiotic/synbiotic decreased some of the inflammatory markers. The intervention was most effective in CRP and TNF-α reduction in healthy or disease state. Moreover, the intervention decreased inflammation most effectively in the following disease conditions, respectively: IBD, arthritis, fatty liver. PROSPERO REGISTRATION NUMBER: CRD42018088688.

Probiotics in Extraintestinal Diseases: Current Trends and New Directions

Probiotics are defined as live microorganisms that when administered in adequate amounts confer a health benefit to the host. Their positive supplementation outcomes on several gastrointestinal disorders are well defined. Nevertheless, their actions are not limited to the gut, but may also impart their beneficial effects at distant sites and organs. In this regard, in this review article we: (i) comprehensively describe the main mechanisms of action of probiotics at distant sites, including bones, skin, and brain; (ii) critically present their therapeutic potential against bone, skin, and neuronal diseases (e.g., osteoporosis, non-healing wounds and autoimmune skin illnesses, mood, behavior, memory, and cognitive impairments); (iii) address the current gaps in the preclinical and clinical research; and (iv) indicate new research directions and suggest future investigations.

Impact of bacterial probiotics on obesity, diabetes and non-alcoholic fatty liver disease related variables: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To systematically review the effect of oral intake of bacterial probiotics on 15 variables related to obesity, diabetes and non-alcoholic fatty liver disease.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, EMBASE and COCHRANE from 1990 to June 2018.

ELIGIBILITY CRITERIA

Randomised controlled trials (≥14 days) excluding hypercholesterolaemia, alcoholic liver disease, polycystic ovary syndrome and children <3 years.

RESULTS

One hundred and five articles met inclusion criteria, representing 6826 subjects. In overweight but not obese subjects, probiotics induced improvements in: body weight (k=25 trials, d=-0.94 kg mean difference, 95% CI -1.17 to -0.70, I²=0.0%), body mass index (k=32, d=-0.55 kg/m², 95% CI -0.86 to -0.23, I²=91.9%), waist circumference (k=13, d=-1.31 cm, 95% CI -1.79 to -0.83, I²=14.5%), body fat mass (k=11, d=-0.96 kg, 95% CI -1.21 to -0.71, I²=0.0%) and visceral adipose tissue mass (k=5, d=-6.30 cm², 95% CI -9.05 to -3.56, I²=0.0%). In type 2 diabetics, probiotics reduced fasting glucose (k=19, d=-0.66 mmol/L, 95% CI -1.00 to -0.31, I²=27.7%), glycated haemoglobin (k=13, d=-0.28 pp, 95% CI -0.46 to -0.11, I²=54.1%), insulin (k=13, d=-1.66 mU/L, 95% CI -2.70 to -0.61, I²=37.8%) and homeostatic model of insulin resistance (k=10, d=-1.05 pp, 95% CI -1.48 to -0.61, I²=18.2%). In subjects with fatty liver diseases, probiotics reduced alanine (k=12, d=-10.2 U/L, 95% CI -14.3 to -6.0, I²=93.50%) and aspartate aminotransferases (k=10, d=-9.9 U/L, 95% CI -14.1 to -5.8, I²=96.1%). These improvements were mostly observed with bifidobacteria (Bifidobacterium breve, B. longum), Streptococcus salivarius subsp. thermophilus and lactobacilli (Lactobacillus acidophilus, L. casei, L. delbrueckii) containing mixtures and influenced by trials conducted in one country.

CONCLUSIONS

The intake of probiotics resulted in minor but consistent improvements in several metabolic risk factors in subjects with metabolic diseases.

TRIAL REGISTRATION NUMBER

CRD42016033273.

The effect of probiotics on inflammatory biomarkers: a meta-analysis of randomized clinical trials

PURPOSE

No study has summarized earlier findings on the effect of probiotic supplementation on inflammatory biomarkers. This systematic review and meta-analysis was conducted to systematically review the available placebo-controlled clinical trials about the effect of probiotic supplementation on several inflammatory biomarkers in adults.

METHODS

Relevant papers published up to March 2018 were searched up through PubMed, MEDLINE, SCOPUS, EMBASE, and Google Scholar, using following suitable keywords. Clinical trials that examined the effect of probiotic supplementation on inflammation in adults were included.

RESULTS

Overall, 42 randomized clinical trials (1138 participants in intervention and 1120 participants in control groups) were included. Combining findings from included studies, we found a significant reduction in serum hs-CRP [standardized mean difference (SMD) - 0.46; 95% CI - 0.73, - 0.19], TNF-a (- 0.21; - 0.34, - 0.08), IL-6 (- 0.37; - 0.51, - 0.24), IL-12 (- 0.47; - 0.67, - 0.27), and IL-4 concentrations (- 0.48; - 0.76, - 0.20) after probiotic supplementation. Pooling effect sizes from 11 studies with 12 effect sizes, a significant increase in IL-10 concentrations was seen (0.21; 0.04, 0.38). We failed to find a significant effect of probiotic supplementation on serum IL-1B (- 0.17; - 0.37, 0.02), IL-8 (- 0.01; - 0.30, 0.28), and IFN-g (- 0.08; - 0.31, 0.15) and IL-17 concentrations (0.06; - 0.34, 0.46).

CONCLUSIONS

Probiotic supplementation significantly reduced serum concentrations of pro-inflammatory cytokines including, hs-CRP, TNF-a, IL-6, IL-12, and IL-4, but it did not influence IL-1B, IL-8, IFN-g, and IL-17 concentrations. A significant increase in serum concentrations of IL-10, as a anti-inflammatory cytokine was also documented after probiotic supplementation.

Vitamin D and probiotic co-supplementation affects mental health, hormonal, inflammatory and oxidative stress parameters in women with polycystic ovary syndrome

Objective

The aim of this study was to determine the effect of vitamin D and probiotic co-administration on mental health, hormonal, inflammatory and oxidative stress parameters in women with polycystic ovary syndrome (PCOS).

Methods

This randomized, double-blinded, placebo-controlled clinical trial was carried out on 60 subjects, aged 18–40 years old. Subjects were randomly allocated to take either 50,000 IU vitamin D every 2 weeks plus 8 × 10⁹ CFU/day probiotic (n = 30) or placebo (n = 30) for 12 weeks.

Results

Vitamin D and probiotic co-supplementation, compared with the placebo, significantly improved beck depression inventory [β (difference in the mean of outcomes measures between treatment groups) − 0.58; 95% CI, − 1.15, − 0.02; P = 0.04], general health questionnaire scores (β − 0.93; 95% CI, − 1.78, − 0.08; P = 0.03) and depression, anxiety and stress scale scores (β − 0.90; 95% CI, − 1.67, − 0.13; P = 0.02). Vitamin D and probiotic co-supplementation was associated with a significant reduction in total testosterone (β − 0.19 ng/mL; 95% CI, − 0.28, − 0.10; P < 0.001), hirsutism (β − 0.95; 95% CI, − 1.39, − 0.51; P < 0.001), high-sensitivity C-reactive protein (hs-CRP) (β − 0.67 mg/L; 95% CI, − 0.97, − 0.38; P < 0.001) and malondialdehyde (MDA) levels (β − 0.25 μmol/L; 95% CI, − 0.40, − 0.10; P = 0.001), and a significant increase in total antioxidant capacity (TAC) (β 82.81 mmol/L; 95% CI, 42.86, 122.75; P < 0.001) and total glutathione (GSH) levels (β 40.42 μmol/L; 95% CI, 4.69, 76.19; P = 0.02), compared with the placebo.

Conclusions

Overall, the co-administration of vitamin D and probiotic for 12 weeks to women with PCOS had beneficial effects on mental health parameters, serum total testosterone, hirsutism, hs-CRP, plasma TAC, GSH and MDA levels.

Trial Registration

This study was retrospectively registered in the Iranian website (www.irct.ir) for registration of clinical trials (IRCT20170513033941N37).

Cross-species examination of single- and multi-strain probiotic treatment effects on neuropsychiatric outcomes

Interest in elucidating gut-brain-behavior mechanisms and advancing neuropsychiatric disorder treatments has led to a recent proliferation of probiotic trials. Yet, a considerable gap remains in our knowledge of probiotic efficacy across populations and experimental contexts. We conducted a cross-species examination of single- and multi-strain combinations of established probiotics. Forty-eight human (seven infant/child, thirty-six young/middle-aged adult, five older adult) and fifty-eight non-human (twenty-five rat, twenty-seven mouse, five zebrafish, one quail) investigations met the inclusion/exclusion criteria. Heterogeneity of probiotic strains, substrains, and study methodologies limited our ability to conduct meta-analyses. Human trials detected variations in anxiety, depression, or emotional regulation (single-strain 55.6%; multi-strain 50.0%) and cognition or social functioning post-probiotic intake (single-strain 25.9%; multi-strain 31.5%). For the non-human studies, single- (60.5%) and multi-strain (45.0%) combinations modified stress, anxiety, or depression behaviors in addition to altering social or cognitive performance (single-strain 57.9%; multi-strain 85.0%). Rigorous trials that confirm existing findings, investigate additional probiotic strain/substrain combinations, and test novel experimental paradigms, are necessary to develop future probiotic treatments that successfully target specific neuropsychiatric outcomes.

Immunomodulatory effects of probiotics: Can they be used to treat allergies and autoimmune diseases?

As a person ages, physiological, immunological and gut microbiome changes collectively result in an array of chronic conditions. According to the 'hygiene hypothesis' the increasing prevalence of immune-mediated disorders may be related to intestinal dysbiosis, leading to immune dysfunction and associated conditions such as eczema, asthma, allergies and autoimmune diseases. Beneficial probiotic bacteria can be utilized by increasing their abundance within the gastrointestinal lumen, which in turn will modulate immune cells, such as, T helper (Th)-1, Th2, Th17, regulatory T (Treg) cells and B cells, which have direct relevance to human health and the pathogenesis of immune disorders. Here, we describe the cross-talk between probiotics and the gastrointestinal immune system, and their effects in relation to inflammatory bowel disease, multiple sclerosis, allergies and atopic dermatitis.

Probiotics in Autoimmune and Inflammatory Disorders

Probiotics have been used to ameliorate gastrointestinal symptoms since ancient times. Over the past 40 years, probiotics have been shown to impact the immune system, both in vivo and in vitro. This interaction is linked to gut microbes, their polysaccharide antigens, and key metabolites produced by these bacteria. At least four metabolic pathways have been implicated in mechanistic studies of probiotics, based on mechanistic studies in animal models. Microbial⁻immune system crosstalk has been linked to: short-chain fatty acid production and signaling, tryptophan metabolism and the activation of aryl hydrocarbon receptors, nucleoside signaling in the gut, and activation of the intestinal histamine-2 receptor. Several randomized controlled trials have now shown that microbial modification by probiotics may improve gastrointestinal symptoms and multiorgan inflammation in rheumatoid arthritis, ulcerative colitis, and multiple sclerosis. Future work will need to carefully assess safety issues, selection of optimal strains and combinations, and attempts to prolong the duration of colonization of beneficial microbes.

Focus on the gut-brain axis: Multiple sclerosis, the intestinal barrier and the microbiome

The brain-gut axis serves as the bidirectional connection between the gut microbiome, the intestinal barrier and the immune system that might be relevant for the pathophysiology of inflammatory demyelinating diseases. People with multiple sclerosis have been shown to have an altered microbiome, increased intestinal permeability and changes in bile acid metabolism. Experimental evidence suggests that these changes can lead to profound alterations of peripheral and central nervous system immune regulation. Besides being of pathophysiological interest, the brain-gut axis could also open new avenues of therapeutic targets. Modification of the microbiome, the use of probiotics, fecal microbiota transplantation, supplementation with bile acids and intestinal barrier enhancers are all promising candidates. Hopefully, pre-clinical studies and clinical trials will soon yield significant results.

Microbial modulation of the gut microbiome for treating autoimmune diseases

Many studies have shown the relationship between autoimmune diseases and the gut microbiome in humans: those with autoimmune conditions display gut microbiome dysbiosis. The big question that needs to be addressed is if restoring eubiosis of the gut microbiota can help suppress the autoimmune condition by activating various immune regulatory mechanisms. Inducing these self-healing mechanisms should prolong good health in affected individuals. Area covered: Here, we review the available clinical and preclinical studies that have used selective bacteria for modulating gut microbiota for treating autoimmune diseases. The potential bacterial candidates and their mechanism of action in treating autoimmune diseases will be discussed. We searched for genetically modified and potential probiotics for diseases and discuss the most likely candidates. Expert commentary: To achieve eubiosis, manipulation of the gut microbiota must occur in some form. Several approaches for modulating gut microbiota include prebiotic diets, antimicrobial interventions, fecal microbiota transplants, and selective probiotics. One novel approach showing promising results is the use of selective bacterial candidates to modulate microbial composition. Use of single microbe for treatment has an advantage as compared to multi-species as microbes grow at different rates and if needed, a single microbe is easy to target.

Does Severity of Alzheimer's Disease Contribute to Its Responsiveness to Modifying Gut Microbiota? A Double Blind Clinical Trial

Alzheimer's disease (AD) is associated with cognitive dysfunction. Evidence indicates that gut microbiota is altered in the AD and, hence, modifying the gut flora may affect the disease. In the previous clinical research we evaluated the effect of a probiotic combination on the cognitive abilities of AD patients. Since, in addition to pathological disorders, the AD is associated with changes in oxidant/antioxidant and inflammatory/anti-inflammatory biomarkers, the present work was designed to evaluate responsiveness of the inflammatory and oxidative biomarkers to the probiotic treatment. The control (CON) and probiotic (PRO) AD patients were treated for 12 weeks by the placebo and probiotic supplementation, respectively. The patients were cognitively assessed by Test Your Memory (TYM = 50 scores). Also serum concentrations of nitric oxide (NO), glutathione (GSH), total antioxidant capacity (TAC), malondialdehyde (MDA), 8-hydroxy-2′ -deoxyguanosine (8-OHdG) and cytokines (TNF-a, IL-6, and IL-10) were measured. The cognitive test and the serum biomarkers were assessed pre- and post-treatment. According to TYM test 83.5% of the patients showed severe AD. The CON (12.86% ± 8.33) and PRO (−9.35% ± 16.83) groups not differently scored the cognitive test. Not pronounced change percent was found in the serum level of TNF-α (1.67% ± 1.33 vs. −0.15% ± 0.27), IL-6 (0.35% ± 0.17 vs. 2.18% ± 0.15), IL-10 (0.05% ± 0.10 vs. −0.70% ± 0.73), TAC (0.07% ± 0.07 and −0.06% ± 0.03), GSH (0.08% ± 0.05 and 0.04% ± 0.03) NO (0.11% ± 0.06 and 0.05% ± 0.09), MDA (−0.11% ± 0.03 and −0.17% ± 0.03), 8-OHdG (43.25% ± 3.01 and 42.70% ± 3.27) in the CON and PRO groups, respectively. We concluded that the cognitive and biochemical indications in the patients with severe AD are insensitive to the probiotic supplementation. Therefore, in addition to formulation and dosage of probiotic bacteria, severity of disease and time of administration deeply affects results of treatment.

The effects of probiotic and selenium co-supplementation on mental health parameters and metabolic profiles in type 2 diabetic patients with coronary heart disease: A randomized, double-blind, placebo-controlled trial

BACKGROUND AND AIMS

The objective of this investigation was to assess the effects of probiotic and selenium co-supplementation on indicators of mental health and metabolic profiles in diabetic people with coronary heart disease (CHD).

METHODS

This randomized, double-blind, placebo-controlled trial was conducted among 54 diabetic people with CHD. Patients were randomly allocated into two groups to receive either 200 μg/day selenium plus 8 × 10⁹ CFU/day probiotic (n = 27) or placebo (n = 27) for 12 weeks.

RESULTS

Probiotic and selenium co-supplementation significantly decreased Beck Depression Inventory index (β -1.46; 95% CI, -2.61, -0.31; P = 0.01) and Beck Anxiety Inventory index (β -1.23; 95% CI, -2.33, -0.12; P = 0.02) compared with the placebo. Consuming probiotic plus selenium lowered fasting plasma glucose (β -10.80 mg/dL; 95% CI, -17.68, -3.92; P = 0.003), serum insulin levels (β -3.42 μIU/mL; 95% CI, -4.93, -1.90; P < 0.001), insulin resistance (β -0.96; 95% CI, -1.45, -0.47; P < 0.001), and enhanced insulin sensitivity (β 0.01; 95% CI, 0.007, 0.01; P < 0.001) compared with the placebo. Additionally, co-supplementation reduced triglycerides (β -34.45 mg/dL; 95% CI, -56.18, -12.72; P = 0.003), VLDL- (β -6.89 mg/dL; 95% CI, -11.23, -2.54; P = 0.003), total cholesterol (β -18.13 mg/dL; 95% CI, -23.42, -2.83; P = 0.02) and high sensitivity C-reactive protein (β -1043.28 ng/mL; 95% CI, -1929.67, -156.89; P = 0.02), and increased nitric oxide (β 7.86 μmol/L; 95% CI, 5.63, 10.09; P < 0.001), total antioxidant capacity (β 119.30 mmol/L; 95% CI, 63.04, 175.57; P < 0.001) and total glutathione (β 154.16 μmol/L; 95% CI, 82.57, 225.74; P < 0.001) compared with the placebo.

CONCLUSIONS

Probiotic and selenium co-supplementation to diabetic people with CHD improved indicators of mental health and metabolic profiles. Registered under Clinical Trials.gov Identifier no. http://www.irct.ir: IRCT20170513033941N28.

The effects of vitamin D and probiotic co-supplementation on mental health parameters and metabolic status in type 2 diabetic patients with coronary heart disease: A randomized, double-blind, placebo-controlled trial

BACKGROUND

This study was carried out to evaluate the effects of vitamin D and probiotic co-supplementation on mental health parameters and metabolic status in diabetic people with coronary heart disease (CHD).

METHODS

This randomized, double-blind, placebo-controlled trial was carried out among 60 diabetic people with CHD, aged 45-85 years old. Subjects were randomly allocated into two groups to receive either 50,000 IU vitamin D every 2 weeks plus 8 × 10⁹ CFU/g probiotic of Lactocare Zisttakhmir Co (n = 30) or placebo (n = 30) for 12 weeks. Fasting blood samples were obtained at baseline and after the 12-week intervention to determine metabolic profiles.

RESULTS

After the 12-week intervention, compared with the placebo, vitamin D and probiotic co-supplementation resulted in significant improvements in beck depression inventory total score (-2.8 ± 3.8 vs. -0.9 ± 2.1, P = 0.01), beck anxiety inventory scores (-2.1 ± 2.3 vs. -0.8 ± 1.4, P = 0.009) and general health questionnaire scores (-3.9 ± 4.1 vs. -1.1 ± 3.4, P = 0.005). Compared with the placebo, vitamin D and probiotic co-supplementation resulted in significant reductions in serum insulin levels (-2.8 ± 3.8 vs. +0.2 ± 4.9 μIU/mL, P = 0.009), homeostasis model of assessment-estimated insulin resistance (-1.0 ± 1.6 vs. -0.1 ± 1.5, P = 0.02), and a significant increase in serum 25-OH-vitamin D (+11.8 ± 5.9 vs. +0.1 ± 1.4 ng/mL, P < 0.001), the quantitative insulin sensitivity check index (+0.03 ± 0.04 vs. -0.001 ± 0.01, P = 0.003) and serum HDL-cholesterol levels (+2.3 ± 3.5 vs. -0.5 ± 3.8 mg/dL, P = 0.004). In addition, changes in serum high sensitivity C-reactive protein (hs-CRP) (-950.0 ± 1811.2 vs. +260.5 ± 2298.2 ng/mL, P = 0.02), plasma nitric oxide (NO) (+1.7 ± 4.0 vs. -1.4 ± 6.7 μmol/L, P = 0.03) and plasma total antioxidant capacity (TAC) (+12.6 ± 41.6 vs. -116.9 ± 324.2 mmol/L, P = 0.03) in the supplemented group were significantly different from the changes in these indicators in the placebo group.

CONCLUSIONS

Overall, vitamin D and probiotic co-supplementation after 12 weeks among diabetic people with CHD had beneficial effects on mental health parameters, serum hs-CRP, plasma NO, TAC, glycemic control and HDL-cholesterol levels.

CLINICAL TRIAL REGISTRATION NUMBER

http://www.irct.ir: IRCT2017073033941N4.

Connecting the immune system, systemic chronic inflammation and the gut microbiome: The role of sex

Unresolved low grade systemic inflammation represents the underlying pathological mechanism driving immune and metabolic pathways involved in autoimmune diseases (AID). Mechanistic studies in animal models of AID and observational studies in patients have found alterations in gut microbiota communities and their metabolites, suggesting a microbial contribution to the onset or progression of AID. The gut microbiota and its metabolites have been shown to influence immune functions and immune homeostasis both within the gut and systematically. Microbial derived-short chain fatty acid (SCFA) and bio-transformed bile acid (BA) have been shown to influence the immune system acting as ligands specific cell signaling receptors like GPRCs, TGR5 and FXR, or via epigenetic processes. Similarly, intestinal permeability (leaky gut) and bacterial translocation are important contributors to chronic systemic inflammation and, without repair of the intestinal barrier, might represent a continuous inflammatory stimulus capable of triggering autoimmune processes. Recent studies indicate gender-specific differences in immunity, with the gut microbiota shaping and being concomitantly shaped by the hormonal milieu governing differences between the sexes. A bi-directional cross-talk between microbiota and the endocrine system is emerging with bacteria being able to produce hormones (e.g. serotonin, dopamine and somatostatine), respond to host hormones (e.g. estrogens) and regulate host hormones' homeostasis (e.g by inhibiting gene prolactin transcription or converting glucocorticoids to androgens). We review herein how gut microbiota and its metabolites regulate immune function, intestinal permeability and possibly AID pathological processes. Further, we describe the dysbiosis within the gut microbiota observed in different AID and speculate how restoring gut microbiota composition and its regulatory metabolites by dietary intervention including prebiotics and probiotics could help in preventing or ameliorating AID. Finally, we suggest that, given consistent observations of microbiota dysbiosis associated with AID and the ability of SCFA and BA to regulate intestinal permeability and inflammation, further mechanistic studies, examining how dietary microbiota modulation can protect against AID, hold considerable potential to tackle increased incidence of AID at the population level.

A probiotic modulates the microbiome and immunity in multiple sclerosis

OBJECTIVE

Effect of a probiotic on the gut microbiome and peripheral immune function in healthy controls and relapsing-remitting multiple sclerosis (MS) patients.

METHODS

MS patients (N = 9) and controls (N = 13) were orally administered a probiotic containing Lactobacillus, Bifidobacterium, and Streptococcus twice-daily for two months. Blood and stool specimens were collected at baseline, after completion of the 2-month treatment, and 3 months after discontinuation of therapy. Frozen peripheral blood mononuclear cells (PBMCs) were used for immune cell profiling. Stool samples were used for 16S rRNA profiling and metabolomics.

RESULTS

Probiotic administration increased the abundance of several taxa known to be depleted in MS such as Lactobacillus. We found that probiotic use decreased the abundance of taxa previously associated with dysbiosis in MS, including Akkermansia and Blautia. Predictive metagenomic analysis revealed a decrease in the abundance of several KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways associated with altered gut microbiota function in MS patients, such as methane metabolism, following probiotic supplementation. At the immune level, probiotic administration induced an anti-inflammatory peripheral immune response characterized by decreased frequency of inflammatory monocytes, decreased mean fluorescence intensity (MFI) of CD80 on classical monocytes, as well as decreased human leukocyte antigen (HLA) D related MFI on dendritic cells. Probiotic administration was also associated with decreased expression of MS risk allele HLA-DQA1 in controls. Probiotic-induced increase in abundance of Lactobacillus and Bifidobacterium was associated with decreased expression of MS risk allele HLA.DPB1 in controls.

INTERPRETATION

Our results suggest that probiotics could have a synergistic effect with current MS therapies. Ann Neurol 2018.

Clinical and metabolic response to probiotic administration in people with Parkinson's disease: A randomized, double-blind, placebo-controlled trial

BACKGROUND & AIMS

The investigation was done to assess the impacts of probiotic supplementation on movement and metabolic parameters in individuals with Parkinson's disease (PD).

METHODS

The study is randomized, double-blind, placebo-controlled clinical trial, which was done in sixty people with PD. Individuals were randomly divided into two groups in order to take either 8 × 10⁹ CFU/day probiotic or placebo (n = 30 each group) that lasted 12 weeks. The Movement Disorders Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) was recorded at pre- and post-intervention.

RESULTS

Compared with the placebo, consuming probiotic decreased MDS-UPDRS (-4.8 ± 12.5 vs. +3.8 ± 13.0, P = 0.01). Probiotic supplementation also reduced high-sensitivity C-reactive protein (-1.6 ± 2.5 vs. +0.1 ± 0.3 mg/L, P < 0.001) and malondialdehyde (-0.2 ± 0.3 vs. +0.1 ± 0.3 μmol/L, P = 0.006), and enhanced glutathione levels (+40.1 ± 81.5 vs. -12.1 ± 41.7 μmol/L, P = 0.03) in comparison with the placebo. Additionally, probiotic consumption resulted in a statistically significant reduction in insulin levels (-2.1 ± 3.4 vs. +1.5 ± 5.1 μIU/mL, P = 0.002) and insulin resistance (-0.5 ± 0.9 vs. +0.4 ± 1.2, P = 0.002), and a statistically significant rise in insulin sensitivity (+0.01 ± 0.02 vs. -0.006 ± 0.02, P = 0.01) in comparison with the placebo. Probiotic intake had no any significant impact on other metabolic profiles.

CONCLUSIONS

Our study evidenced that 12 weeks of probiotic consumption by individuals with PD had useful impacts on MDS-UPDRS and few metabolic profiles. Registered under ClinicalTrials.gov Identifier no. http://www.irct.ir: IRCT2017082434497N4.

Gut microbiota derived metabolites in cardiovascular health and disease

Trillions of microbes inhabit the human gut, not only providing nutrients and energy to the host from the ingested food, but also producing metabolic bioactive signaling molecules to maintain health and elicit disease, such as cardiovascular disease (CVD). CVD is the leading cause of mortality worldwide. In this review, we presented gut microbiota derived metabolites involved in cardiovascular health and disease, including trimethylamine-N-oxide (TMAO), uremic toxins, short chain fatty acids (SCFAs), phytoestrogens, anthocyanins, bile acids and lipopolysaccharide. These gut microbiota derived metabolites play critical roles in maintaining a healthy cardiovascular function, and if dysregulated, potentially causally linked to CVD. A better understanding of the function and dynamics of gut microbiota derived metabolites holds great promise toward mechanistic predicative CVD biomarker discoveries and precise interventions.

Microbiome-host systems interactions: protective effects of propionate upon the blood-brain barrier

BACKGROUND

Gut microbiota composition and function are symbiotically linked with host health and altered in metabolic, inflammatory and neurodegenerative disorders. Three recognised mechanisms exist by which the microbiome influences the gut-brain axis: modification of autonomic/sensorimotor connections, immune activation, and neuroendocrine pathway regulation. We hypothesised interactions between circulating gut-derived microbial metabolites, and the blood-brain barrier (BBB) also contribute to the gut-brain axis. Propionate, produced from dietary substrates by colonic bacteria, stimulates intestinal gluconeogenesis and is associated with reduced stress behaviours, but its potential endocrine role has not been addressed.

RESULTS

After demonstrating expression of the propionate receptor FFAR3 on human brain endothelium, we examined the impact of a physiologically relevant propionate concentration (1 μM) on BBB properties in vitro. Propionate inhibited pathways associated with non-specific microbial infections via a CD14-dependent mechanism, suppressed expression of LRP-1 and protected the BBB from oxidative stress via NRF2 (NFE2L2) signalling.

CONCLUSIONS

Together, these results suggest gut-derived microbial metabolites interact with the BBB, representing a fourth facet of the gut-brain axis that warrants further attention.

Intestinal Lactobacillus in health and disease, a driver or just along for the ride?

Metagenomics and related methods have led to significant advances in our understanding of the human microbiome. Members of the genus Lactobacillus, although best understood for essential roles in food fermentations and applications as probiotics, have also come to the fore in a number of untargeted gut microbiome studies in humans and animals. Even though Lactobacillus is only a minor member of the human colonic microbiota, the proportions of those bacteria are frequently either positively or negatively correlated with human disease and chronic conditions. Recent findings on Lactobacillus species in human and animal microbiome research, together with the increased knowledge on probiotic and other ingested lactobacilli, have resulted in new perspectives on the importance of this genus to human health.

Gut microbiota and probiotics: novel immune system modulators in myasthenia gravis?

Gut microorganisms (microbiota) live in symbiosis with the host and influence human nutrition, metabolism, physiology, and immune development and function. The microbiota prevents pathogen infection to the host, and in turn the host provides a niche for survival. The alteration of gut bacteria composition (dysbiosis) could contribute to the development of immune-mediated diseases by influencing the immune system activation and driving the pro- and anti-inflammatory responses in order to promote or counteract immune reactions. Probiotics are nonpathogenic microorganisms able to interact with the gut microbiota and provide health benefits; their use has recently been exploited to dampen immunological response in several experimental models of autoimmune diseases. Here, we focus on the relationships among commensal bacteria, probiotics, and the gut, describing the main interactions occurring with the immune system and recent data supporting the clinical efficacy of probiotic administration in rheumatoid arthritis, multiple sclerosis, and myasthenia gravis (MG) animal models. The encouraging results suggest that selected strains of probiotics should be evaluated in clinical trials as adjuvant therapy to restore the disrupted tolerance in myasthenia gravis.

Combined therapies to treat complex diseases: The role of the gut microbiota in multiple sclerosis

The commensal microbiota has emerged as an environmental risk factor for multiple sclerosis (MS). Studies in experimental autoimmune encephalomyelitis (EAE) models have shown that the commensal microbiota is an essential player in triggering autoimmune demyelination. Likewise, the commensal microbiota modulates the host immune system, alters the integrity and function of biological barriers and has a direct effect on several types of central nervous system (CNS)-resident cells. Moreover, a characteristic gut dysbiosis has been recognized as a consistent feature during the clinical course of MS, and the MS-related microbiota is gradually being elucidated. This review highlights animal studies in which commensal microbiota modulation was tested in EAE, as well as the mechanisms of action and influence of the commensal microbiota not only in the local milieu but also in the innate and adaptive immune system and the CNS. Regarding human research, this review focuses on studies that show how the commensal microbiota might act as a pathogenic environmental risk factor by directing immune responses towards characteristic pathogenic profiles of MS. We speculate how specific microbiome signatures could be obtained and used as potential pathogenic events and biomarkers for the clinical course of MS. Finally, we review recently published and ongoing clinical trials in MS patients regarding the immunomodulatory properties exerted by some microorganisms. Because MS is a complex disease with a large variety of associated environmental risk factors, we suggest that current treatments combined with strategies that modulate the commensal microbiota would constitute a broader immunotherapeutic approach and improve the clinical outcome for MS patients.

The Effects of Probiotic Supplementation on Gene Expression Related to Inflammation, Insulin, and Lipids in Patients With Multiple Sclerosis: A Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

Limited data are available assessing the effects of probiotic supplementation on gene expression related to inflammation, insulin, and lipids in patients with multiple sclerosis (MS).

OBJECTIVES

The current study was conducted to assess the effects of probiotic supplementation on gene expression related to inflammation, insulin, and lipids in patients with MS.

METHODS

This randomized, double-blind, placebo-controlled clinical trial was performed among 40 patients with MS. Participants were randomly assigned into two groups to receive either a probiotic capsule containing Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum, and Lactobacillus fermentum (2 × 109 colony-forming units/g each; n = 20) or placebo (n = 20) for 12 weeks. Gene expression related to inflammation, insulin, and lipids was quantified in blood samples of patients with MS with the reverse transcription polymerase chain reaction (RT-PCR) method.

RESULTS

We found that compared with placebo, probiotic supplementation down-regulated gene expression of interleukin-8 (IL-8; p < 0.001) and tumor necrosis factor-alpha (TNF-α) mRNA (p < .001) in peripheral blood mononuclear cells of patients with MS. We did not observe any significant effect of probiotic supplementation on gene expression of interleukin-1 (IL-1), peroxisome proliferator-activated receptor gamma (PPAR-γ), or oxidized low-density lipoprotein receptor (LDLR) in peripheral blood mononuclear cells of patients with MS.

CONCLUSIONS

Overall, probiotic supplementation for 12 weeks in patients with MS significantly improved gene expression of IL-8 and TNF-α but did not influence IL-1, PPAR-γ, or LDLR.

Immunoregulatory effect of mast cells influenced by microbes in neurodegenerative diseases

When related to central nervous system (CNS) health and disease, brain mast cells (MCs) can be a source of either beneficial or deleterious signals acting on neural cells. We review the current state of knowledge about molecular interactions between MCs and glia in neurodegenerative diseases such as Multiple Sclerosis, Alzheimer's disease, Amyotrophic Lateral Sclerosis, Parkinson's disease, Epilepsy. We also discuss the influence on MC actions evoked by the host microbiota, which has a profound effect on the host immune system, inducing important consequences in neurodegenerative disorders. Gut dysbiosis, reduced intestinal motility and increased intestinal permeability, that allow bacterial products to circulate and pass through the blood-brain barrier, are associated with neurodegenerative disease. There are differences between the microbiota of neurologic patients and healthy controls. Distinguishing between cause and effect is a challenging task, and the molecular mechanisms whereby remote gut microbiota can alter the brain have not been fully elucidated. Nevertheless, modulation of the microbiota and MC activation have been shown to promote neuroprotection. We review this new information contributing to a greater understanding of MC-microbiota-neural cells interactions modulating the brain, behavior and neurodegenerative processes.

Gut inflammation and dysbiosis in human motor neuron disease

Amyotrophic lateral sclerosis (ALS) is a systemic disorder that involves dysfunction of multiple organs. Growing evidence has shown that neurodegenerative disorders with gut dysbiosis affect the central nervous system via pro-inflammatory mediators thus impacting gut-brain communications. We have demonstrated dysbiosis and increased intestinal permeability in the SOD1G93A ALS mouse model. In this study, we comprehensively examined the human gut microbiome in stool samples and evaluated infection and markers of intestinal inflammation in five patients with ALS and motor neuron disorders. Five patients we studied all had alteration in their gut microbiome characterized by a low diversity of the microbiome, compared to healthy cohorts with relatively intact abundance. Firmicutes and Bacteroidetes are the two major members of bacteria at the phylum level. Low Ruminococcus spp occurred in three patients with low Firmicutes/Bacteroidetes (F/B) ratio. A majority of patients had signs of intestinal inflammation. This is the first comprehensive examination of inflammatory markers in the stool of ALS patients. Studies in gut health and microbiome related to the onset and progression of ALS may reveal novel therapeutic targets for disease modulation.

Intestinal dysbiosis and probiotic applications in autoimmune diseases

In humans, a complex interaction between the host immune system and commensal microbiota is required to maintain gut homeostasis. In this symbiotic relationship, the microbiota provides carbohydrate fermentation and digestion, vitamin synthesis and gut-associated lymphoid tissue development, as well as preventing colonization by pathobionts, whereas the host offers a niche and nutrients for the survival of the microbiota. However, when this mutualistic relationship is compromised and an altered interaction between immune cells and microorganisms occurs, the gut microbiota may cause or contribute to the establishment of infectious diseases and trigger autoimmune diseases. Researchers have made efforts to clarify the role of the microbiota in autoimmune disease development and find new therapeutic approaches to treat immune-mediated diseases. However, the exact mechanisms involved in the dysbiosis and breakdown of the gut epithelial barrier are currently unknown. Here, we provide a general overview of studies describing gut microbiota perturbations in animal models of autoimmune diseases, such as type 1 diabetes, multiple sclerosis, rheumatoid arthritis and systemic lupus erythematosus. Moreover, we include the main studies concerning dysbiosis in humans and a critical discussion of the existing data on the use of probiotics in these autoimmune diseases.

Effect of Probiotic Supplementation on Cognitive Function and Metabolic Status in Alzheimer's Disease: A Randomized, Double-Blind and Controlled Trial

Alzheimer's disease (AD) is associated with severe cognitive impairments as well as some metabolic defects. Scant studies in animal models indicate a link between probiotics and cognitive function. This randomized, double-blind, and controlled clinical trial was conducted among 60 AD patients to assess the effects of probiotic supplementation on cognitive function and metabolic status. The patients were randomly divided into two groups (n = 30 in each group) treating with either milk (control group) or a mixture of probiotics (probiotic group). The probiotic supplemented group took 200 ml/day probiotic milk containing Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum, and Lactobacillus fermentum (2 × 10⁹ CFU/g for each) for 12 weeks. Mini-mental state examination (MMSE) score was recorded in all subjects before and after the treatment. Pre- and post-treatment fasting blood samples were obtained to determine the related markers. After 12 weeks intervention, compared with the control group (-5.03% ± 3.00), the probiotic treated (+27.90% ± 8.07) patients showed a significant improvement in the MMSE score (P <0.001). In addition, changes in plasma malondialdehyde (-22.01% ± 4.84 vs. +2.67% ± 3.86 μmol/L, P <0.001), serum high-sensitivity C-reactive protein (-17.61% ± 3.70 vs. +45.26% ± 3.50 μg/mL, P <0.001), homeostasis model of assessment-estimated insulin resistance (+28.84% ± 13.34 vs. +76.95% ± 24.60, P = 0.002), Beta cell function (+3.45% ± 10.91 vs. +75.62% ± 23.18, P = 0.001), serum triglycerides (-20.29% ± 4.49 vs. -0.16% ± 5.24 mg/dL, P = 0.003), and quantitative insulin sensitivity check index (-1.83 ± 1.26 vs. -4.66 ± 1.70, P = 0.006) in the probiotic group were significantly varied compared to the control group. We found that the probiotic treatment had no considerable effect on other biomarkers of oxidative stress and inflammation, fasting plasma glucose, and other lipid profiles. Overall, the current study demonstrated that probiotic consumption for 12 weeks positively affects cognitive function and some metabolic statuses in the AD patients.

CLINICAL TRIAL REGISTRATION

http://www.irct.ir/, IRCT201511305623N60.