Streptococcus thermophilus ST285 Alters Pro-Inflammatory to Anti-Inflammatory Cytokine Secretion against Multiple Sclerosis Peptide in Mice

Control of Helicobacter pylori with engineered probiotics secreting selective guided antimicrobial peptides

Helicobacter pylori is the primary cause of 78% of gastric cancer cases, providing an opportunity to prevent cancer by controlling a single bacterial pathogen within the complex gastric microbiota. We developed highly selective antimicrobial agents against H. pylori by fusing an H. pylori-binding guide peptide (MM1) to broad-spectrum antimicrobial peptides. The common dairy probiotic Lactococcus lactis was then engineered to secrete these guided antimicrobial peptides (gAMPs). When co-cultured in vitro with H. pylori, the gAMP probiotics lost no toxicity compared to unguided AMP probiotics against the target, H. pylori, while losing >90% of their toxicity against two tested off-target bacteria. To test binding to H. pylori, the MM1 guide was fused to green fluorescent protein (GFP), resulting in enhanced binding compared to unguided GFP as measured by flow cytometry. In contrast, MM1-GFP showed no increased binding over GFP against five different off-target bacteria. These highly selective gAMP probiotics were then tested by oral gavage in mice infected with H. pylori. As a therapy, the probiotics outperformed antibiotic treatment, effectively eliminating H. pylori in just 5 days, and also protected mice from challenge infection as a prophylactic. As expected, the gAMP probiotics were as toxic against H. pylori as the unguided AMP probiotics. However, a strong rebound in gastric species diversity was found with both the selective gAMP probiotics and the non-selective AMP probiotics. Eliminating the extreme microbial dysbiosis caused by H. pylori appeared to be the major factor in diversity recovery. IMPORTANCE Alternatives to antibiotics in the control of Helicobacter pylori and the prevention of gastric cancer are needed. The high prevalence of H. pylori in the human population, the induction of microbial dysbiosis by antibiotics, and increasing antibiotic resistance call for a more sustainable approach. By selectively eliminating the pathogen and retaining the commensal community, H. pylori control may be achieved without adverse health outcomes. Antibiotics are typically used as a therapeutic post-infection, but a more targeted, less disruptive approach could be used as a long-term prophylactic against H. pylori or, by extension, against other gastrointestinal pathogens. Furthermore, the modular nature of the guided antimicrobial peptide (gAMP) technology allows for the substitution of different guides for different pathogens and the use of a cocktail of gAMPs to avoid the development of pathogen resistance.

Network-Based Prediction of Side Effects of Repurposed Antihypertensive Sartans against COVID-19 via Proteome and Drug-Target Interactomes

The potential of targeting the Renin-Angiotensin-Aldosterone System (RAAS) as a treatment for the coronavirus disease 2019 (COVID-19) is currently under investigation. One way to combat this disease involves the repurposing of angiotensin receptor blockers (ARBs), which are antihypertensive drugs, because they bind to angiotensin-converting enzyme 2 (ACE2), which in turn interacts with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. However, there has been no in silico analysis of the potential toxicity risks associated with the use of these drugs for the treatment of COVID-19. To address this, a network-based bioinformatics methodology was used to investigate the potential side effects of known Food and Drug Administration (FDA)-approved antihypertensive drugs, Sartans. This involved identifying the human proteins targeted by these drugs, their first neighbors, and any drugs that bind to them using publicly available experimentally supported data, and subsequently constructing proteomes and protein-drug interactomes. This methodology was also applied to Pfizer's Paxlovid, an antiviral drug approved by the FDA for emergency use in mild-to-moderate COVID-19 treatment. The study compares the results for both drug categories and examines the potential for off-target effects, undesirable involvement in various biological processes and diseases, possible drug interactions, and the potential reduction in drug efficiency resulting from proteoform identification.

Multiple Sclerosis-Related Dietary and Nutritional Issues: An Updated Scoping Review with a Focus on Pediatrics

PURPOSE

Lifestyle/dietetic habits play an important role in the development and progression of multiple sclerosis (MS) disease. Here, we examine the basic pathomechanisms underlying intestinal and brain barrier modifications in MS and consider diets and dietary supplementations proposed over time to complement pharmacological therapies for improving disease outcome both in adults and in children.

METHODS

Scoping literature search about evidence-based findings in MS-related gut-brain axis (GBA) pathophysiology and nutritional issues at all ages.

FINDINGS

Data show that (1) no universal best diet exists, (2) healthy/balanced diets are, however, necessary to safeguard the adequate intake of all essential nutrients, (3) diets with high intakes of fruits, vegetables, whole grains, and lean proteins that limit processed foods, sugar, and saturated fat appear beneficial for their antioxidant and anti-inflammatory properties and their ability to shape a gut microbiota that respects the gut and brain barriers, (4) obesity may trigger MS onset and/or its less favorable course, especially in pediatric-onset MS. Vitamin D and polyunsaturated fatty acids are the most studied supplements for reducing MS-associated inflammation.

CONCLUSIONS

Pending results from other and/or newer approaches targeting the GBA (e.g., pre- and probiotics, engineered probiotics, fecal-microbiota transplantation), accurate counseling in choosing adequate diet and maintaining physical activity remains recommended for MS prevention and management both in adults and children.

Computational and Enzymatic Studies of Sartans in SARS-CoV-2 Spike RBD-ACE2 Binding: The Role of Tetrazole and Perspectives as Antihypertensive and COVID-19 Therapeutics

This study is an extension of current research into a novel class of synthetic antihypertensive drugs referred to as "bisartans", which are bis-alkylated imidazole derivatives bearing two symmetric anionic biphenyltetrazoles. Research to date indicates that bisartans are superior to commercially available hypertension drugs, since the former undergo stronger docking to angiotensin-converting enzyme 2 (ACE2). ACE2 is the key receptor involved in SARS-CoV-2 entry, thus initiating COVID-19 infection and in regulating levels of vasoactive peptides such as angiotensin II and beneficial heptapeptides A(1-7) and Alamandine in the renin-angiotensin system (RAS). In previous studies using in vivo rabbit-iliac arterial models, we showed that Na⁺ or K⁺ salts of selected Bisartans initiate a potent dose-response inhibition of vasoconstriction. Furthermore, computational studies revealed that bisartans undergo stable binding to the vital interfacial region between ACE2 and the SARS-CoV-2 "receptor binding domain" (i.e., the viral RBD). Thus, bisartan homologs are expected to interfere with SARS-CoV-2 infection and/or suppress disease expression in humans. The primary goal of this study was to investigate the role of tetrazole in binding and the network of amino acids of SARS-CoV-2 Spike RBD-ACE2 complex involved in interactions with sartans. This study would, furthermore, allow the expansion of the synthetic space to create a diverse suite of new bisartans in conjunction with detailed computational and in vitro antiviral studies. A critical role for tetrazole was uncovered in this study, shedding light on the vital importance of this group in the binding of sartans and bisartans to the ACE2/Spike complex. The in silico data predicting an interaction of tetrazole-containing sartans with ACE2 were experimentally validated by the results of surface plasmon resonance (SPR) analyses performed with a recombinant human ACE2 protein.

Evaluation of Potential Probiotic Properties of Limosilactobacillus fermentum Derived from Piglet Feces and Influence on the Healthy and E. coli-Challenged Porcine Intestine

In this work, we evaluated the probiotic properties of Limosilactobacillus fermentum strains (FL1, FL2, FL3, FL4) isolated from feces of healthy piglets. The in vitro auto-aggregation, hydrophobicity, biofilm-forming capacity, survival in the gastrointestinal tract, antimicrobial activity and anti-oxidation capacity were evaluated. Four strains were resistant to simulated gastrointestinal conditions, including low pH, pepsin, trypsin and bile salts. They also maintained strong self-aggregation and cell surface hydrophobicity. Limosilactobacillus fermentum FL4, which had the strongest adhesion ability and antimicrobial effect on Enterotoxigenic Escherichia coli K88 (ETEC K88), was then tested in porcine intestinal organoid models. The in vitro experiments in basal-out and apical-out organoids demonstrated that L. fermentum FL4 adhered to the apical surfaces more efficiently than basolateral surfaces, had the ability to activate the Wnt/β-catenin pathway to protect the mucosal barrier integrity, stimulated the proliferation and differentiation of the intestinal epithelium, and repaired ETEC K88-induced damage. Moreover, L. fermentum FL4 inhibited inflammatory responses induced by ETEC K88 through the reduced expression of pro-inflammatory cytokines (TNF-α, IL-1β and IFN-γ) and higher levels of anti-inflammatory cytokines (TGF-β and IL-10). These results show that L. fermentum FL4 isolated from feces of healthy Tunchang piglets has the potential to be used as an anti-inflammatory probiotic and for mitigation of intestinal damage in piglets.

Molecular Epidemiology of SARS-CoV-2: The Dominant Role of Arginine in Mutations and Infectivity

Background, Aims, Methods, Results, Conclusions: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global challenge due to its ability to mutate into variants that spread more rapidly than the wild-type virus. The molecular biology of this virus has been extensively studied and computational methods applied are an example paradigm for novel antiviral drug therapies. The rapid evolution of SARS-CoV-2 in the human population is driven, in part, by mutations in the receptor-binding domain (RBD) of the spike (S-) protein, some of which enable tighter binding to angiotensin-converting enzyme (ACE2). More stable RBD-ACE2 association is coupled with accelerated hydrolysis by proteases, such as furin, trypsin, and the Transmembrane Serine Protease 2 (TMPRSS2) that augment infection rates, while inhibition of the 3-chymotrypsin-like protease (3CL^pro) can prevent the viral replication. Additionally, non-RBD and non-interfacial mutations may assist the S-protein in adopting thermodynamically favorable conformations for stronger binding. This study aimed to report variant distribution of SARS-CoV-2 across European Union (EU)/European Economic Area (EEA) countries and relate mutations with the driving forces that trigger infections. Variants' distribution data for SARS-CoV-2 across EU/EEA countries were mined from the European Centre for Disease Prevention and Control (ECDC) based on the sequence or genotyping data that are deposited in the Global Science Initiative for providing genomic data (GISAID) and The European Surveillance System (TESSy) databases. Docking studies performed with AutoDock VINA revealed stabilizing interactions of putative antiviral drugs, e.g., selected anionic imidazole biphenyl tetrazoles, with the ACE2 receptor in the RBD-ACE2 complex. The driving forces of key mutations for Alpha, Beta, Gamma, Delta, Epsilon, Kappa, Lambda, and Omicron variants, which stabilize the RBD-ACE2 complex, were investigated by computational approaches. Arginine is the critical amino acid in the polybasic furin cleavage sites S1/S2 (681-PRRARS-686) S2' (814-KRS-816). Critical mutations into arginine residues that were found in the delta variant (L452R, P681R) and may be responsible for the increased transmissibility and morbidity are also present in two widely spreading omicron variants, named BA.4.6 and BQ.1, where mutation R346T in the S-protein potentially contributes to neutralization escape. Arginine binders, such as Angiotensin Receptor Blockers (ARBs), could be a class of novel drugs for treating COVID-19.

Probiotics and Commensal Gut Microbiota as the Effective Alternative Therapy for Multiple Sclerosis Patients Treatment

The gut-brain axis (GBA) refers to the multifactorial interactions between the intestine microflora and the nervous, immune, and endocrine systems, connecting brain activity and gut functions. Alterations of the GBA have been revealed in people with multiple sclerosis (MS), suggesting a potential role in disease pathogenesis and making it a promising therapeutic target. Whilst research in this field is still in its infancy, a number of studies revealed that MS patients are more likely to exhibit modified microbiota, altered levels of short-chain fatty acids, and enhanced intestinal permeability. Both clinical and preclinical trials in patients with MS and animal models revealed that the administration of probiotic bacteria might improve cognitive, motor, and mental behaviors by modulation of GBA molecular pathways. According to the newest data, supplementation with probiotics may be associated with slower disability progression, reduced depressive symptoms, and improvements in general health in patients with MS. Herein, we give an overview of how probiotics supplementation may have a beneficial effect on the course of MS and its animal model. Hence, interference with the composition of the MS patient's intestinal microbiota may, in the future, be a grip point for the development of diagnostic tools and personalized microbiota-based adjuvant therapy.

Probiotics and prebiotics alleviate behavioral deficits, inflammatory response, and gut dysbiosis in prenatal VPA-induced rodent model of autism

Autism spectrum disorders are neuropsychiatric conditions characterized by social interaction and communication disorders and repetitive stereotypical behaviors. These disorders are also accompanied by an inflammatory status. Bidirectional communication between microbiome, gut, and brain has been discovered as a major mechanism influencing core symptoms and biomarkers of autism. Therefore, the modulation of the gut microbiota in autism has recently attracted interest. In this study, probiotic- and prebiotic-mediated modulation of the gut microbiota was compared in terms of different symptoms and findings in an experimental autism model. Valproic acid (VPA) (500 mg/kg) was administered to Wistar rats (on prenatal day 12.5) to induce autistic-like behaviors. Based on the supply of probiotics and prebiotics, animals were grouped as control (saline), autistic-like (prenatal VPA), probiotic (prenatal VPA + 22.5 × 10⁹ cfu/day probiotic), prebiotic (prenatal VPA + 100 mg/day prebiotic), and combined treatment (prenatal VPA + 22.5 × 10⁹ cfu/day probiotic + 100 mg/day prebiotic). After the treatment process, behavioral tests (social behaviors, anxiety, stereotypical behavior, sensorimotor gating, and behavioral despair) and biochemical analyses (serum and brain tissue) were conducted, and the quantities of some phyla and genera were determined in stool samples. Significant positive effects of probiotic and combined treatments were observed on the sociability, social interaction, and anxiety parameters. In addition, all three treatments had positive effects on stereotypical behavior. However, the treatments did not affect sensorimotor gating deficits and behavioral despair. Further, probiotic treatment reversed the VPA-induced increase and decrease in serum IL-6 and IL-10 levels, respectively. Combined treatment also significantly increased the IL-10 levels. Prenatal VPA exposure decreased 5-hydroxytryptamine (5-HT) levels in the prefrontal cortex of the brain; however, combined treatment reversed this decrease. Prenatal VPA exposure also caused a decrease in Bacteroidetes/Firmicutes ratio in the gut microbiota, while the probiotic treatment significantly increased this ratio. These findings indicate that probiotic- and prebiotic-mediated microbial modulation may represent a new therapeutic approach to alleviate autistic-like symptoms.

The Changes in Bacterial Microbiome Associated with Immune Disorder in Allergic Respiratory Disease

Allergic respiratory disease is a worldwide and increasingly prevalent health problem. Many researchers have identified complex changes in the microbiota of the respiratory and intestinal tracts in patients with allergic respiratory diseases. These affect immune response and influence the progression of disease. However, the diversity of bacterial changes in such cases make it difficult to identify a specific microorganism to target for adjustment. Recent research evidence suggests that common bacterial variations present in allergic respiratory disease are associated with immune disorders. This finding could lead to the discovery of potential therapeutic targets in cases of allergic respiratory disease. In this review, we summarize current knowledge of bacteria changes in cases of allergic respiratory disease, to identify changes commonly associated with immune disorders, and thus provide a theoretical basis for targeting therapies of allergic respiratory disease through effective modulation of key bacteria.

Psychobiotics: the Influence of Gut Microbiota on the Gut-Brain Axis in Neurological Disorders

Nervous system disorders are one of the common problems that affect many people around the world every year. Regarding the beneficial effects of the probiotics on the gut and the gut-brain axis, their application along with current medications has been the subject of intense interest. Psychobiotics are a probiotic strain capable to affect the gut-brain axis. The effective role of Psychobiotics in several neurological disorders is documented. Consumption of the Psychobiotics containing nutrients has positive effects on the improvement of microbiota as well as alleviation of some symptoms of central nervous system (CNS) disorders. In the present study, the effects of probiotic strains on some CNS disorders in terms of controlling the disease symptoms were reviewed. Finding suggests that Psychobiotics can efficiently alleviate the symptoms of several CNS disorders such as autism spectrum disorders, Parkinson’s disease, multiple sclerosis, insomnia, depression, diabetic neuropathy, and anorexia nervosa. It can be concluded that functional foods containing psychotropic strains can help to improve mental health.

Exploring the Effects of Six Weeks of Resistance Training on the Fecal Microbiome of Older Adult Males: Secondary Analysis of a Peanut Protein Supplemented Randomized Controlled Trial

The bacteria inhabiting the gastrointestinal tract contribute to numerous host functions and can be altered by lifestyle factors. We aimed to determine whether a 6-week training intervention altered fecal microbiome diversity and/or function in older males. Fecal samples were collected prior to and following a 6-week twice-weekly supervised resistance training intervention in 14 older Caucasian males (65 ± 10 years, 28.5 ± 3.2 kg/m2) with minimal prior training experience. Participants were randomized to receive a daily defatted peanut powder supplement providing 30 g protein (n = 8) or no supplement (n = 6) during the intervention. Bacterial DNA was isolated from pre-and post-training fecal samples, and taxa were identified using sequencing to amplify the variable region 4 (V4) of the 16S ribosomal RNA gene. Training significantly increased whole-body and lower-body lean mass (determined by dual energy X-ray absorptiometry) as well as leg extensor strength (p < 0.05) with no differences between intervention groups. Overall composition of the microbiome and a priori selected taxa were not significantly altered with training. However, MetaCYC pathway analysis indicated that metabolic capacity of the microbiome to produce mucin increased (p = 0.047); the tight junction protein, zonulin, was measured in serum and non-significantly decreased after training (p = 0.062). Our data suggest that resistance training may improve intestinal barrier integrity in older Caucasian males; further investigation is warranted.

In Vitro Anti-Inflammatory Activity of Peptides Obtained by Tryptic Shaving of Surface Proteins of Streptococcus thermophilus LMD-9

Streptococcus thermophilus, a lactic acid bacterium widely used in the dairy industry, is consumed regularly by a significant proportion of the population. Some strains show in vitro anti-inflammatory activity which is not fully understood. We hypothesized that peptides released from the surface proteins of this bacterium during digestion could be implied in this activity. Consequently, we prepared a peptide hydrolysate by shaving and hydrolysis of surface proteins using trypsin, and the origin of peptides was checked by liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis. Most of the identified peptides originated from bacterial cell surface proteins. The anti-inflammatory activity of peptide hydrolysate was investigated under inflammatory conditions in two cell models. Peptide hydrolysate significantly decreased secretion of pro-inflammatory cytokine IL-8 in lipopolysaccharide (LPS)-stimulated human colon epithelial HT-29 cells. It also reduced the production of pro-inflammatory cytokines IL-8, IL-1β and the protein expression levels of Pro-IL-1β and COX-2 in LPS-stimulated THP-1 macrophages. The results showed that peptides released from bacterial surface proteins by a pancreatic protease could therefore participate in an anti-inflammatory activity of S. thermophilus LMD-9 and could prevent low-grade inflammation.

Assessment of Yeasts as Potential Probiotics: A Review of Gastrointestinal Tract Conditions and Investigation Methods

Probiotics are microorganisms (including bacteria, yeasts and moulds) that confer various health benefits to the host, when consumed in sufficient amounts. Food products containing probiotics, called functional foods, have several health-promoting and therapeutic benefits. The significant role of yeasts in producing functional foods with promoted health benefits is well documented. Hence, there is considerable interest in isolating new yeasts as potential probiotics. Survival in the gastrointestinal tract (GIT), salt tolerance and adherence to epithelial cells are preconditions to classify such microorganisms as probiotics. Clear understanding of how yeasts can overcome GIT and salt stresses and the conditions that support yeasts to grow under such conditions is paramount for identifying, characterising and selecting probiotic yeast strains. This study elaborated the adaptations and mechanisms underlying the survival of probiotic yeasts under GIT and salt stresses. This study also discussed the capability of yeasts to adhere to epithelial cells (hydrophobicity and autoaggregation) and shed light on in vitro methods used to assess the probiotic characteristics of newly isolated yeasts.

Immune Modulatory Effects of Probiotic Streptococcus thermophilus on Human Monocytes

Ingesting probiotics contributes to the development of a healthy microflora in the GIT with established benefits to human health. Some of these beneficial effects may be through the modulation of the immune system. In addition, probiotics have become more common in the treatment of many inflammatory and immune disorders. Here, we demonstrate a range of immune modulating effects of Streptococcus thermophilus by human monocytes, including decreased mRNA expression of IL-1R, IL-18, IFNαR1, IFNγR1, CCL2, CCR5, TLR-1, TLR-2, TLR-4, TLR-5, TLR-6, TLR-8, CD14, CD86, CD4, ITGAM, LYZ, TYK2, IFNR1, IRAK-1, NOD2, MYD88, SLC11A1, and increased expression of IL-1α, IL-1β, IL-2, IL-6, IL-8, IL-23, IFNγ, TNFα, CSF-2. The routine administration of Streptococcus thermophilus in fermented dairy products and their consumption may be beneficial to the treatment/management of inflammatory and autoimmune diseases.

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

BACKGROUND

Probiotics may have a promising role in chronic autoinflammatory diseases. The current systematic review and meta-analysis investigated the effects of probiotics on disease progression, depression, general health, and anthropometric measurements in Relapsing-Remitting Multiple Sclerosis (RRMS) patients.

METHODS

The English literature search was performed using PubMed, Scopus, Web of Science, and the Central Cochrane Library through January 2021. Random effect models were used to synthesise quantitative data by STATA₁₄ .

RESULTS

From a total of 152 identified entries, four trials were included in quantitative synthesis (n = 213; 106 as intervention, 107 as control). An additional six studies with the same structure and different markers were also systematically reviewed. The pooled effect size showed that Expanded Disability Status Scale (EDSS) (WMD = -0.43; 95% CI = -0.65, -0.20; P < .001), Beck Depression Inventory-Ⅱ (BDI-Ⅱ) (WMD = -3.22; 95% CI = -4.38, -2.06; P < .001) and General Health Questionnaire (GHQ) (WMD = -4.37; 95% CI = -6.43, -2.31; P < .001) were improved following probiotics supplementation. However, body weight and body mass index did not statistically change.

CONCLUSION

Our findings revealed that probiotics supplementation can improve disease progression, suppress depression, and general health in MS patients; although, further investigations may be needed.

Combination of Probiotics and Natural Compounds to Treat Multiple Sclerosis via Warburg Effect

Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system (CNS). It is an auto-immune disorder. Its usual symptoms are unique to each person. In MS lesions vast fractions of pyruvate molecules are instantly transformed into lactate. This reprogramming mechanism of glycolysis is known as the Warburg effect. MS has no efficient treatment yet. Hence, there is a requirement for profitable immunomodulatory agents in MS. Probiotics perform as an immunomodulator because they regulate the host’s immune responses. Its efficacy gets enhanced for an extended period when it combines with prebiotics. In this review, we focus on the metabolic alterations behind the MS lesions via the Warburg effect, and also suggesting, the combined efficacy of prebiotics and probiotics for the effective treatment of MS without side effects. The Warburg effect mechanism intensifies the infiltration of activated T-cells and B-cells into the CNS. It provokes the inflammation process on the myelin sheath. The infiltration of immune cells can be inhibited by the combination therapy of probiotics and prebiotics. By this review, we can recommend that the idea of this combinational therapy can do miracles in the treatment of MS in the future.

Gut dysbiosis, defective autophagy and altered immune responses in neurodegenerative diseases: Tales of a vicious cycle

The human microbiota comprises trillions of symbiotic microorganisms and is involved in regulating gastrointestinal (GI), immune, nervous system and metabolic homeostasis. Recent observations suggest a bidirectional communication between the gut microbiota and the brain via immune, circulatory and neural pathways, termed the Gut-Brain Axis (GBA). Alterations in gut microbiota composition, such as seen with an increased number of pathobionts and a decreased number of symbionts, termed gut dysbiosis or microbial intestinal dysbiosis, plays a prominent role in the pathogenesis of central nervous system (CNS)-related disorders. Clinical reports confirm that GI symptoms often precede neurological symptoms several years before the development of neurodegenerative diseases (NDDs). Pathologically, gut dysbiosis disrupts the integrity of the intestinal barrier leading to ingress of pathobionts and toxic metabolites into the systemic circulation causing GBA dysregulation. Subsequently, chronic neuroinflammation via dysregulated immune activation triggers the accumulation of neurotoxic misfolded proteins in and around CNS cells resulting in neuronal death. Emerging evidence links gut dysbiosis to the aggravation and/or spread of proteinopathies from the peripheral nervous system to the CNS and defective autophagy-mediated proteinopathies. This review summarizes the current understanding of the role of gut microbiota in NDDs, and highlights a vicious cycle of gut dysbiosis, immune-mediated chronic neuroinflammation, impaired autophagy and proteinopathies, which contributes to the development of neurodegeneration in Alzheimer's disease, Parkinson's disease, Huntington's disease, multiple sclerosis, amyotrophic lateral sclerosis and frontotemporal lobar degeneration. We also discuss novel therapeutic strategies targeting the modulation of gut dysbiosis through prebiotics, probiotics, synbiotics or dietary interventions, and faecal microbial transplantation (FMT) in the management of NDDs.

Nutritional and ecological perspectives of the interrelationships between diet and the gut microbiome in multiple sclerosis: Insights from marmosets

Studies in experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis, have shown potential links between diet components, microbiome composition, and modulation of immune responses. In this review, we reanalyze and discuss findings in an outbred marmoset EAE model in which a yogurt-based dietary supplement decreased disease frequency and severity. We show that although diet has detectable effects on the fecal microbiome, microbiome changes are more strongly associated with the EAE development. Using an ecological framework, we further show that the dominant factors influencing the gut microbiota were marmoset sibling pair and experimental time point. These findings emphasize challenges in assigning cause-and-effect relationships in studies of diet-microbiome-host interactions and differentiating the diet effects from other environmental, stochastic, and host-related factors. We advocate for animal experiments to be designed to allow causal inferences of the microbiota's role in pathology while considering the complex ecological processes that shape microbial communities.

Lactobacillus fermentum (MTCC-5898) alleviates Escherichia coli-induced inflammatory responses in intestinal epithelial cells by modulating immune genes and NF-κB signalling

AIM

Dietary intervention using probiotic bacteria has emerged as a promising preventive strategy in addressing foodborne infections or gastrointestinal disorders. This study investigated the immunomodulatory effects of Lactobacillus fermentum (MTCC-5898) on Escherichia coli-induced inflammatory responses in intestinal epithelial cells.

METHODS AND RESULTS

The immune response of intestinal cells (Caco-2) in the presence of probiotic Lact. fermentum was determined during exclusion, competition and displacement of E. coli as the inflammatory agent. To achieve this objective, transcriptional modulation of key immune-related genes (cytokines, pattern recognition receptors and NF-κB), release of cytokines and nuclear translocation of the NF-κB subunit p-65 were studied. Expression of pro-inflammatory cytokines IL-8, TNF-α, IFN-ϒ and IL-23 was high in E. coli-exposed intestinal cells. However, overexpression of these E. coli-induced pro-inflammatory cytokines was prevented by Lact. fermentum during exclusion and competition assays. It also modulated the transcriptional expression of regulatory cytokines (IL-10 and TGF-β), pattern recognition receptors (TLR-2 and TLR-4) and genes associated with master inflammatory regulators (NF-κB and SIGIRR) to reduce E. coli-induced inflammation. The protective effect of Lact. fermentum was further confirmed by suppression of nuclear translocation of cytoplasmic NF-κB subunit (p-65).

CONCLUSION

Lactobacillus fermentum alleviated E. coli-induced inflammatory responses by modulating the NF-κB signalling besides pro-inflammatory and regulatory cytokines expression.

SIGNIFICANCE AND IMPACT OF THE STUDY

Lactobacillus fermentum holds significant promise as a potent nutraceutical that prevents and manages inflammatory gut-associated dysfunctions.

Efficacy of probiotics in multiple sclerosis: a systematic review of preclinical trials and meta-analysis of randomized controlled trials

Preliminary evidence shows the potential role of probiotics in ameliorating multiple sclerosis (MS); however, the effects of probiotics on MS remain unclear.

The Microbiota-Gut-Brain Axis and Alzheimer's Disease: Neuroinflammation Is to Blame?

For years, it has been reported that Alzheimer’s disease (AD) is the most common cause of dementia. Various external and internal factors may contribute to the early onset of AD. This review highlights a contribution of the disturbances in the microbiota–gut–brain (MGB) axis to the development of AD. Alteration in the gut microbiota composition is determined by increase in the permeability of the gut barrier and immune cell activation, leading to impairment in the blood–brain barrier function that promotes neuroinflammation, neuronal loss, neural injury, and ultimately AD. Numerous studies have shown that the gut microbiota plays a crucial role in brain function and changes in the behavior of individuals and the formation of bacterial amyloids. Lipopolysaccharides and bacterial amyloids synthesized by the gut microbiota can trigger the immune cells residing in the brain and can activate the immune response leading to neuroinflammation. Growing experimental and clinical data indicate the prominent role of gut dysbiosis and microbiota–host interactions in AD. Modulation of the gut microbiota with antibiotics or probiotic supplementation may create new preventive and therapeutic options in AD. Accumulating evidences affirm that research on MGB involvement in AD is necessary for new treatment targets and therapies for AD.

Advances in Multiple Sclerosis Research-Series I

Designing immunotherapeutics, drugs, and anti-inflammatory reagents has been at the forefront of autoimmune research, in particular, multiple sclerosis, for over 20 years. Delivery methods that are used to modulate effective and long-lasting immune responses have been the major focus. This Special Issue, “Advances in Multiple Sclerosis Research—Series I”, focused on delivery methods used for immunotherapeutic approaches, drug design, anti-inflammatories, identification of markers, methods for detection and monitoring MS and treatment modalities. The issue gained much attention with 20 publications, and, as a result, we launched Series II with the deadline for submission being 30 April 2021.

Gut-Brain Axis: Role of Gut Microbiota on Neurological Disorders and How Probiotics/Prebiotics Beneficially Modulate Microbial and Immune Pathways to Improve Brain Functions

The gut microbiome acts as an integral part of the gastrointestinal tract (GIT) that has the largest and vulnerable surface with desirable features to observe foods, nutrients, and environmental factors, as well as to differentiate commensals, invading pathogens, and others. It is well-known that the gut has a strong connection with the central nervous system (CNS) in the context of health and disease. A healthy gut with diverse microbes is vital for normal brain functions and emotional behaviors. In addition, the CNS controls most aspects of the GI physiology. The molecular interaction between the gut/microbiome and CNS is complex and bidirectional, ensuring the maintenance of gut homeostasis and proper digestion. Besides this, several mechanisms have been proposed, including endocrine, neuronal, toll-like receptor, and metabolites-dependent pathways. Changes in the bidirectional relationship between the GIT and CNS are linked with the pathogenesis of gastrointestinal and neurological disorders; therefore, the microbiota/gut-and-brain axis is an emerging and widely accepted concept. In this review, we summarize the recent findings supporting the role of the gut microbiota and immune system on the maintenance of brain functions and the development of neurological disorders. In addition, we highlight the recent advances in improving of neurological diseases by probiotics/prebiotics/synbiotics and fecal microbiota transplantation via the concept of the gut-brain axis.

The potential application of probiotics and prebiotics for the prevention and treatment of COVID-19

COVID-19 is a pandemic disease caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This new viral infection was first identified in China in December 2019, and it has subsequently spread globally. The lack of a vaccine or curative treatment for COVID-19 necessitates a focus on other strategies to prevent and treat the infection. Probiotics consist of single or mixed cultures of live microorganisms that can beneficially affect the host by maintaining the intestinal or lung microbiota that play a major role in human health. At present, good scientific evidence exists to support the ability of probiotics to boost human immunity, thereby preventing colonization by pathogens and reducing the incidence and severity of infections. Herein, we present clinical studies of the use of probiotic supplementation to prevent or treat respiratory tract infections. These data lead to promising benefits of probiotics in reducing the risk of COVID-19. Further studies should be conducted to assess the ability of probiotics to combat COVID-19.

Leucocyte-Rich Platelet-Rich Plasma Enhances Fibroblast and Extracellular Matrix Activity: Implications in Wound Healing

Background: Platelet-rich plasma (PRP) is an autologous blood product that contains a high concentration of platelets and leucocytes, which are fundamental fibroblast proliferation agents. Literature has emerged that offers contradictory findings about leucocytes within PRP. Herein, we elucidated the effects of highly concentrated leucocytes and platelets on human fibroblasts. Methods: Leucocyte-rich, PRP (LR-PRP) and leucocyte-poor, platelet-poor plasma (LP-PPP) were compared to identify their effects on human fibroblasts, including cell proliferation, wound healing and extracellular matrix and adhesion molecule gene expressions. Results: The LR-PRP exhibited 1422.00 ± 317.21 × 10³ platelets/µL and 16.36 ± 2.08 × 10³ white blood cells/µL whilst the LP-PPP demonstrated lower concentrations of 55.33 ± 10.13 × 10³ platelets/µL and 0.8 ± 0.02 × 10³ white blood cells/µL. LR-PRP enhanced fibroblast cell proliferation and cell migration, and demonstrated either upregulation or down-regulation gene expression profile of the extracellular matrix and adhesion molecules. Conclusion: LR-PRP has a continuous stimulatory anabolic and ergogenic effect on human fibroblast cells.

The Long Road of Immunotherapeutics against Multiple Sclerosis

This commentary highlights novel immunomodulation and vaccine-based research against multiple sclerosis (MS) and reveals the amazing story that triggered this cutting-edge MS research in Greece and worldwide. It further reveals the interest and solid support of some of the world's leading scientists, including sixteen Nobel Laureates who requested from European leadership to take action in supporting Greece and its universities in the biggest ever financial crisis the country has encountered in the last decades. This support endorsed vaccine-based research on MS, initiated in Greece and Australia, leading to a worldwide network aiming to treat or manage disease outcomes. Initiatives by bright and determined researchers can result in frontiers science. We shed light on a unique story behind great research on MS which is a step forward in our efforts to develop effective treatments for MS.