Effect of probiotics supplementation on disease progression, depression, general health, and anthropometric measurements in relapsing-remitting multiple sclerosis patients: A systematic review and meta-analysis of clinical trials

Effect of Mediterranean diet on body mass index and fatigue severity in patients with multiple sclerosis: A systematic review and meta-analysis of clinical trials

Background

Recent studies imply that Mediterranean Diet (MeD) may play an important role in the management of Multiple Sclerosis (MS). This meta-analysis aimed to evaluate the effectiveness of MeD in addressing MS-related complications.

Methods

A thorough search was performed in MEDLINE (PubMed), Scopus, EMBASE, ScienceDirect, Google Scholar, Web of Science, and the Central Cochrane Library, covering trials published until September 2023. The quantitative data were synthesized using random effect models through STATA14.

Results

After analyzing 228 entries, we found five Randomized Controlled Trials (RCTs) with a total of 540 participants, who had an average disease duration of 8.5 years. The combined effect size revealed a decrease in Body Mass Index (BMI) (Weighted Mean Difference [WMD] = -0.88 kg/m2; 95 % Confidence Interval [CI] = -1.68, -0.08; P = 0.030). There was also a non-significant marginal improvement in fatigue severity (WMD = -8.29; 95 % CI = -16.74, 0.16; P = 0.054).

Conclusion

Adherence to MeD may improve BMI and fatigue severity in MS patients. Further RCTs are needed to confirm the current results.

Effects of probiotics supplementation in gastrointestinal complications and quality of life of patients with systemic sclerosis: A systematic review

Background

Systemic sclerosis (SSc), as an autoimmune rheumatic disease characterized by immune dysregulation and vasculopathy, affects multiple organs. Due to the high burden of its symptoms on the health care system, this study aims to investigate the effects of probiotic supplements in patients with SSc.

Methods

We searched electronic databases with predefined search terms in PubMed, Scopus, and ISI Web of Science up to June 2023. Randomized controlled trials that evaluated the effects of probiotic supplementation in adult patients suffering from SSc were included in the study. Results of the included studies were reported as weighted mean difference (WMD) with a 95 % confidence interval (CI).

Results

Four studies met the inclusion criteria and were included in the meta-analysis. There was a total of 176 SSc patients. The results show a significant effect of probiotics supplementation on gastrointestinal (GI) symptoms containing reflux (WMD: -0.36, 95 % CI: -0.51 to -0.22, p-value <0.001), gas and bloating (WMD: -0.88, 95 % CI: -1.05 to -0.7, p-value<0.001). However, the results for constipation (WMD: -0.12, 95 % CI: -0.27 to 0.04, p-value = 0.13), diarrhea (WMD: -0.14, 95 % CI: -0.31 to 0.03, p-value = 0.10), and fecal incontinence (WMD: 0.04, 95 % CI: -0.06 to 0.15, p-value = 0.43) were insignificant.

Conclusion

Supplementing with probiotics may alleviate a few numbers of GI complications in SSc. Nevertheless, due to the limited number of studies, more well-designed studies are needed to strengthen these results.

Relationship between gut microbiota and multiple sclerosis: a scientometric visual analysis from 2010 to 2023

Background

Numerous studies have investigated the relationship between gut microbiota (GM) and multiple sclerosis(MS), highlighting the significant role of GM in MS. However, there is a lack of systematic Scientometric analyses published in this specific research area to provide an overall understanding of the current research status.

Methods

Perform a scientometric analysis on research conducted between 2010 and 2023 concerning the link between GM and MS using quantitative and visual analysis software (CiteSpace and VOSviewer.).

Results

From January 1, 2010, and December 31, 2023, a total of 1019 records about GM and MS were retrieved. The number of publications exhibited a consistent upward trend annually. The United States led in publications, showed the strongest level of collaboration among countries. The University of California, San Francisco stands as the top institution in terms of output, and the most prolific and cited authors were Lloyd H. Kasper and Javier Ochoa-Reparaz from the USA. The research in this field primarily centers on investigating the alterations and associations of GM in MS or EAE, the molecular immunological mechanisms, and the potential of GM-based interventions to provide beneficial effects in MS or EAE. The Keywords co-occurrence network reveals five primary research directions in this field. The most frequently occurring keywords are inflammation, probiotics, diet, dysbiosis, and tryptophan. In recent years, neurodegeneration and neuropsychiatric disorders have been prominent, indicating that the investigation of the mechanisms and practical applications of GM in MS has emerged as a current research focus. Moreover, GM research is progressively extending into the realm of neurodegenerative and psychiatric diseases, potentially becoming future research hotspots.

Conclusions

This study revealed a data-driven systematic comprehension of research in the field of GM in MS over the past 13 years, highlighted noteworthy research within the field, provided us with a clear understanding of the current research status and future trends, providing a valuable reference for researchers venturing into this domain.

Gut flora in multiple sclerosis: implications for pathogenesis and treatment

ABSTRACT

Multiple sclerosis is an inflammatory disorder characterized by inflammation, demyelination, and neurodegeneration in the central nervous system. Although current first-line therapies can help manage symptoms and slow down disease progression, there is no cure for multiple sclerosis. The gut-brain axis refers to complex communications between the gut flora and the immune, nervous, and endocrine systems, which bridges the functions of the gut and the brain. Disruptions in the gut flora, termed dysbiosis, can lead to systemic inflammation, leaky gut syndrome, and increased susceptibility to infections. The pathogenesis of multiple sclerosis involves a combination of genetic and environmental factors, and gut flora may play a pivotal role in regulating immune responses related to multiple sclerosis. To develop more effective therapies for multiple sclerosis, we should further uncover the disease processes involved in multiple sclerosis and gain a better understanding of the gut-brain axis. This review provides an overview of the role of the gut flora in multiple sclerosis.

Causal effects of gut microbiota on multiple sclerosis: A two-sample Mendelian randomization study

BACKGROUND

Gut microbiota alterations in multiple sclerosis (MS) patients have been reported in observational studies, but whether these associations are causal is unclear.

OBJECTIVE

We performed a Mendelian randomization study (MR) to assess the causal effects of gut microbiota on MS.

METHODS

Independent genetic variants associated with 211 gut microbiota phenotypes were selected as instrumental variables from the largest genome-wide association studies (GWAS) previously published by the MiBioGen study. GWAS data for MS were obtained from the International Multiple Sclerosis Genetics Consortium (IMSGC) for primary analysis and the FinnGen consortium for replication and collaborative analysis. Sensitivity analyses were conducted to evaluate heterogeneity and pleiotropy.

RESULTS

After inverse-variance-weighted and sensitivity analysis filtering, seven gut microbiota with potential causal effects on MS were identified from the IMSGC. Only five metabolites remained significant associations with MS when combined with the FinnGen consortium, including genus Anaerofilum id.2053 (odds ratio [OR] = 1.141, 95% confidence interval [CI]: 1.021-1.276, p = .021), Ruminococcus2 id.11374 (OR = 1.190, 95% CI: 1.007-1.406, p = .042), Ruminococcaceae UCG003 id.11361 (OR = 0.822, 95% CI: 0.688-0.982, p = .031), Ruminiclostridium5 id.11355 (OR = 0.724, 95% CI: 0.585-0.895, p = .003), Anaerotruncus id.2054 (OR = 0.772, 95% CI: 0.634-0.940, p = .010).

CONCLUSION

Our MR analysis reveals a potential causal relationship between gut microbiota and MS, offering promising avenues for advancing mechanistic understanding and clinical investigation of microbiota-mediated MS.

The effects of prebiotic, probiotic or synbiotic supplementation on overweight/obesity indicators: an umbrella review of the trials' meta-analyses

Background

There is controversial data on the effects of prebiotic, probiotic, or synbiotic supplementations on overweight/obesity indicators. Thus, we aimed to clarify this role of biotics through an umbrella review of the trials' meta-analyses.

Methods

All meta-analyses of the clinical trials conducted on the impact of biotics on overweight/obesity indicators in general populations, pregnant women, and infants published until June 2023 in PubMed, Web of Sciences, Scopus, Embase, and Cochrane Library web databases included. The meta-analysis of observational and systematic review studies without meta-analysis were excluded. We reported the results by implementing the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) flowchart. The Assessment of Multiple Systematic Reviews-2 (AMSTAR2) and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) systems were used to assess the methodological quality and quality of evidence.

Results

Overall, 97 meta-analysis studies were included. Most studies were conducted on the effect of probiotics in both genders. Consumption of prebiotic: 8-66 g/day, probiotic: 104 -1.35×1015 colony-forming unit (CFU)/day, and synbiotic: 106-1.5×1011 CFU/day and 0.5-300 g/day for 2 to 104 weeks showed a favorable effect on the overweight/obesity indicators. Moreover, an inverse association was observed between biotics consumption and overweight/obesity risk in adults in most of the studies. Biotics did not show any beneficial effect on weight and body mass index (BMI) in pregnant women by 6.6×105-1010 CFU/day of probiotics during 1-25 weeks and 1×109-112.5×109 CFU/capsule of synbiotics during 4-8 weeks. The effect of biotics on weight and BMI in infants is predominantly non-significant. Prebiotics and probiotics used in infancy were from 0.15 to 0.8 g/dL and 2×106-6×109 CFU/day for 2-24 weeks, respectively.

Conclusion

It seems biotics consumption can result in favorable impacts on some anthropometric indices of overweight/obesity (body weight, BMI, waist circumference) in the general population, without any significant effects on birth weight or weight gain during pregnancy and infancy. So, it is recommended to intake the biotics as complementary medications for reducing anthropometric indices of overweight/obese adults. However, more well-designed trials are needed to elucidate the anti-obesity effects of specific strains of probiotics.

Beneficial effects of the probiotics and synbiotics supplementation on anthropometric indices and body composition in adults: A systematic review and meta-analysis

Studies have suggested that probiotics and synbiotics can improve body weight and composition. However, randomized controlled trials (RCTs) demonstrated mixed results. Hence, we performed a systematic review and meta-analysis to evaluate the effectiveness of probiotics and synbiotics on body weight and composition in adults. We searched PubMed/Medline, Ovid/Medline, Scopus, ISI Web of Science, and Cochrane library up to April 2023 using related keywords. We included all RCTs investigating the effectiveness of probiotics and/or synbiotics supplementation on anthropometric indices and body composition among adults. Random-effects models were applied for performing meta-analyses. In addition, we conducted subgroup analyses and meta-regression to explore the non-linear and linear relationship between the length of follow-up and the changes in each outcome. We included a total of 200 trials with 12,603 participants in the present meta-analysis. Probiotics or synbiotics intake led to a significant decrease in body weight (weighted mean difference [WMD]: -0.91 kg; 95% CI: -1.08, -0.75; p < 0.001), body mass index (BMI) (WMD: -0.28 kg/m2 ; 95% CI: -0.36, -0.21; p < 0.001), waist circumference (WC) (WMD: -1.14 cm; 95% CI: -1.42, -0.87; p < 0.001), waist-to-hip ratio (WHR) (WMD: -0.01; 95% CI: -0.01, -0.00; p < 0.001), fat mass (FM) (WMD: -0.92 kg; 95% CI: -1.05, -0.79; p < 0.001), and percentage of body fat (%BF) (WMD: -0.68%; 95% CI: -0.94, -0.42; p < 0.001) compared to controls. There was no difference in fat-free mass (FFM) and lean body mass (LBM). Subgroup analyses indicated that probiotics or synbiotics administered as food or supplement resulted in significant changes in anthropometric indices and body composition. However, compared to controls, FM and %BF values were only reduced after probiotic consumption. Our results showed that probiotics or synbiotics have beneficial effects on body weight, central obesity, and body composition in adults and could be useful as an add on to weight loss products and medications.

Probiotics, prebiotics, and synbiotics in type 1 diabetes mellitus: A systematic review and meta-analysis of clinical trials

Dysbiosis or imbalance of microbes in the gut has been associated with susceptibility and progression of type 1 diabetes mellitus (T1DM). The present systematic review and meta-analysis examined the effects of probiotics, prebiotics, and synbiotics on fasting blood glucose (FBG), haemoglobin A1c (HbA1c), C-peptide, and insulin requirements in T1DM patients. A systematic search for trials published up to October 2022 was conducted in PubMed, EMBASE, Scopus, Google Scholar, ScienceDirect, Web of Science, and the Central Cochrane Library. Random effect models were used to synthesise quantitative data by STATA14 . After the evaluation of 258 identified entries, five randomised controlled trials (n = 356; mean age = 11.7 years old) were included. The pooled effect size showed that FBG decreased following probiotic supplementation (weighted mean difference = -31.24 mg/dL; 95% confidence interval = -45.65, -16.83; p < 0.001), however, there was no significant improvement in serum HbA1c, C-peptide, and insulin requirements. Probiotic supplementation could be a complementary therapeutic strategy in T1DM. The evidence is limited; therefore, it is crucial to conduct more trials.

Targeting gut microbiota: new therapeutic opportunities in multiple sclerosis

Multiple sclerosis (MS) causes long-lasting, multifocal damage to the central nervous system. The complex background of MS is associated with autoimmune inflammation and neurodegeneration processes, and is potentially affected by many contributing factors, including altered composition and function of the gut microbiota. In this review, current experimental and clinical evidence is presented for the characteristics of gut dysbiosis found in MS, as well as for its relevant links with the course of the disease and the dysregulated immune response and metabolic pathways involved in MS pathology. Furthermore, therapeutic implications of these investigations are discussed, with a range of pharmacological, dietary and other interventions targeted at the gut microbiome and thus intended to have beneficial effects on the course of MS.

Effects of anti-Inflammatory-antioxidant-rich diet and co-supplemented synbiotics intervention in patients with progressive forms of multiple sclerosis: a single-center, single-blind randomized clinical trial

BACKGROUND

Current evidence has demonstrated that patients with Multiple Sclerosis (MS) have dysbiotic gut microbiomes, and anti-inflammatory nutritional interventions can normalize this status. Therefore, we aimed to investigate the effects of dietary intervention in patients with progressive forms of MS.

METHODS

Seventy patients with three forms of progressive MS (primary-progressive, secondary-progressive, and progressive-relapsing) were randomly assigned into intervention (daily synbiotics capsule plus anti-inflammatory-antioxidant rich diet) or control (placebo capsule plus dietary recommendations) groups for four months. Faecal calprotectin level, Impact of Vision Impairment (IVI), Gastrointestinal Symptom Rating Scale (GSRS), and anthropometric measurements were evaluated at baseline and trial cessation. Analysis of covariance was conducted and adjusted for age, gender, education level, family history & duration of MS, type of progressive MS, type of main drug, and physical activity.

RESULTS

Sixty-nine participants were included in the final analysis (n of intervention = 34; n of control = 35). Synbiotics and dietary intervention significantly reduced Faecal calprotectin level after six months (110.5 ± 75.9-44.7 ± 49.3 ɥg/g, P < 0.001), and mean changes were statistically significant in comparison with control group. However, intervention did not elicit any change in the anthropometric measurements.

CONCLUSION

Synbiotics supplementation and adherence to an anti-inflammatory-antioxidant-rich diet reduced intestinal inflammation and improved clinical manifestations in progressive forms of MS.Trial registration: Iranian Registry of Clinical Trials identifier: IRCT20141108019853N7..

Anti-inflammatory-antioxidant modifications and synbiotics improved health-related conditions in patients with progressive forms of multiple sclerosis: A single-center, randomized clinical trial

BACKGROUND AND PURPOSE

There is growing evidence that dietary modification can improve clinical manifestations in multiple sclerosis (MS) patients. This study aimed to assess the impact of synbiotics and anti-inflammatory-antioxidant-rich diet on fatigue, pain, gut and bladder status, and sexual function in patients with progressive forms of MS.

MATERIALS AND METHODS

In this single-center, single-blind, randomized, controlled clinical trial, seventy participants with three forms of progressive MS (primary-progressive, secondary-progressive, and progressive-relapsing) were randomly assigned to receive either synbiotics supplement and anti-inflammatory-antioxidant-rich diet or a placebo along with their usual diet for a duration of four months. Modified fatigue impact scale (MFIS), global pain scale (GPS), bladder control scale (BLCS), bowel control scale (BWCS), and sexual satisfaction scale (SSS) were assessed at baseline and at the end of the trial.

RESULTS

Sixty-nine participants successfully completed the trial, resulting in a 98% adherence rate to the diet, and no reports of serious side effects. Significant mean changes were observed in fatigue (Δ for experimental group = -10.5 ± 10.8 vs. Δ for control group = -0.08 ± 4.1; P < 0.001), pain (-14.1 ± 19.0 vs. 0.9 ± 10.3; P < 0.001), bladder (-0.76 ± 2.1 vs. 0.3 ± 1.1; P = 0.013) and bowel (-6.6 ± 3.2 vs. -0.05 ± 2.3; P < 0.001) control, as well as sexual function (-1.0 ± 2.3 vs. 0.51 ± 0.21; P < 0.001).

CONCLUSION

The anti-inflammatory-antioxidant-rich diet and synbiotics co-supplementation demonstrated improvements in fatigue, pain, sexual function, and bowel/bladder status among patients with progressive MS.

Probiotic Influences on Motor Skills: A Review

The effects of probiotics have mostly been shown to be favorable on measures of anxiety and stress. More recent experiments indicate single- and multi-strain probiotics in treating motorrelated diseases. Initial studies in patients with Parkinson's disease and Prader-Willi syndrome are concordant with this hypothesis. In addition, probiotics improved motor coordination in normal animals and models of Parkinson's disease, multiple sclerosis, and spinal cord injury as well as grip strength in hepatic encephalopathy. Further studies should delineate the most optimal bacterial profile under each condition.

Gut Microbes and Neuropathology: Is There a Causal Nexus?

The gut microbiota is a virtual organ which produces a myriad of molecules that the brain and other organs require. Humans and microbes are in a symbiotic relationship, we feed the microbes, and in turn, they provide us with essential molecules. Bacteroidetes and Firmicutes phyla account for around 80% of the total human gut microbiota, and approximately 1000 species of bacteria have been identified in the human gut. In adults, the main factors influencing microbiota structure are diet, exercise, stress, disease and medications. In this narrative review, we explore the involvement of the gut microbiota in Parkinson’s disease, Alzheimer’s disease, multiple sclerosis and autism, as these are such high-prevalence disorders. We focus on preclinical studies that increase the understanding of disease pathophysiology. We examine the potential for targeting the gut microbiota in the development of novel therapies and the limitations of the currently published clinical studies. We conclude that while the field shows enormous promise, further large-scale studies are required if a causal link between these disorders and gut microbes is to be definitively established.

Multiple Sclerosis and Microbiome

The composition of microbiota and the gut-brain axis is increasingly considered a factor in the development of various pathological conditions. The etiology of multiple sclerosis (MS), a chronic autoimmune disease affecting the CNS, is complex and interactions within the gut-brain axis may be relevant in the development and the course of MS. In this article, we focus on the relationship between gut microbiota and the pathophysiology of MS. We review the contribution of germ-free mouse studies to our understanding of MS pathology and its implications for treatment strategies to modulate the microbiome in MS. This summary highlights the need for a better understanding of the role of the microbiota in patients’ responses to disease-modifying drugs in MS and disease activity overall.