Pharmabiotics as an Emerging Medication for Metabolic Syndrome and Its Related Diseases

Assessing the impact of concurrent high-fructose and high-saturated fat diets on pediatric metabolic syndrome: A review

High-saturated fat (HF) or high-fructose (HFr) consumption in children predispose them to metabolic syndrome (MetS). In rodent models of MetS, diets containing individually HF or HFr lead to a variable degree of MetS. Nevertheless, simultaneous intake of HF plus HFr have synergistic effects, worsening MetS outcomes. In children, the effects of HF or HFr intake usually have been addressed individually. Therefore, we have reviewed the outcomes of HF or HFr diets in children, and we compare them with the effects reported in rodents. In humans, HFr intake causes increased lipogenesis, hypertriglyceridemia, obesity and insulin resistance. On the other hand, HF diets promote low grade-inflammation, obesity, insulin resistance. Despite the deleterious effects of simultaneous HF plus HFr intake on MetS development in rodents, there is little information about the combined effects of HF plus HFr intake in children. The aim of this review is to warn about this issue, as individually addressing the effects produced by HF or HFr may underestimate the severity of the outcomes of Western diet intake in the pediatric population. We consider that this is an alarming issue that needs to be assessed, as the simultaneous intake of HF plus HFr is common on fast food menus.

Drug repurposing for metabolic disorders: Scientific, technological and economic issues

Obesity, diabetes, and other metabolic disorders place a huge burden on both the physical health and financial well-being of the community. While the need for effective treatment of metabolic disorders remains urgent and the reality is that traditional drug development involves high costs and a very long time with many pre-clinical and clinical trials, the need for drug repurposing has emerged as a potential alternative. Scientific evidence has shown the anti-diabetic and anti-obesity effects of old drugs, which were initially utilized for the treatment of inflammation, depression, infections, and even cancers. The drug library used modern technological methods to conduct drug screening. Computational molecular docking, genome-wide association studies, or omics data mining are advantageous and unavoidable methods for drug repurposing. Drug repurposing offers a promising avenue for economic efficiency in healthcare, especially for less common metabolic diseases, despite the need for rigorous research and validation. In this chapter, we aim to explore the scientific, technological, and economic issues surrounding drug repurposing for metabolic disorders. We hope to shed light on the potential of this approach and the challenges that need to be addressed to make it a viable option in the treatment of metabolic disorders, especially in the future fight against metabolic disorders.

Lactiplantibacillus plantarum Regulated Intestinal Microbial Community and Cytokines to Inhibit Salmonella typhimurium Infection

Lactic acid bacteria (LAB) are recognized as food-grade safe microorganisms and have many beneficial effects. LAB could maintain the host intestinal homeostasis and regulate intestinal microbial community to exert antibacterial effects. In this study, Lactiplantibacillus plantarum (L. plantarum, Lp01) strain isolated from pig intestine was orally administered to C57BL/6 mice, and mice were then infected with Salmonella typhimurium (ATCC14028). The protective effects of L. plantarum were evaluated by monitoring body weight loss, survival rates, bacterial loads in tissue, colon histopathology analysis, and cytokine secretion. 16S rRNA gene sequencing was also utilized to detect the dynamics of the blind gut microbial community in mice. We found that L. plantarum could significantly reduce the body weight loss and improve the survival rates. The survival rate in the L. P-Sty group was up to 67.5%, which was much higher than that in the STY group (25%). Counting of bacterial loads displayed that the colony-forming unit (CFU) of S. typhimurium in the spleen (p < 0.05) and the liver (p < 0.05) from L. P-Sty group both decreased, compared with STY group. Intestinal histopathology showed that it alleviated the intestinal injury caused by Salmonella, inhibited the secretion of pro-inflammatory cytokines, and promoted anti-inflammatory cytokines (p < 0. 01). In addition, L. plantarum also significantly ameliorated the intestinal gut microbiome disturbance caused by Salmonella. It displayed an obvious increase of beneficial bacteria including Lactobacillus and Bacteroidetes and reduction of pathogenic bacteria like Proteobacteria. In conclusion, L. plantarum could regulate microbial community to inhibit Salmonella typhimurium infection.

Identification of the Intestinal Microbes Associated with Locomotion

Given the impact of the gut microbiome on human physiology and aging, it is possible that the gut microbiome may affect locomotion in the same way as the host's own genes. There is not yet any direct evidence linking the gut microbiome to locomotion, though there are some potential connections, such as regular physical activity and the immune system. In this study, we demonstrate that the gut microbiome can contribute differently to locomotion. We remodeled the original gut microbiome of mice through fecal microbiota transplantation (FMT) using human feces and compared the changes in locomotion of the same mice before and three months after FMT. We found that FMT affected locomotion in three different ways: positive, none (the same), and negative. Analysis of the phylogenesis, α-diversities, and β-diversities of the gut microbiome in the three groups showed that a more diverse group of intestinal microbes was established after FMT in each of the three groups, indicating that the human gut microbiome is more diverse than that of mice. The FMT-remodeled gut microbiome in each group was also different from each other. Fold change and linear correlation analyses identified Lacrimispora indolis, Pseudoflavonifractor phocaeensis, and Alistipes senegalensis in the gut microbiome as positive contributors to locomotion, while Sphingobacterium cibi, Prevotellamassilia timonensis, Parasutterella excrementihominis, Faecalibaculum rodentium, and Muribaculum intestinale were found to have negative effects. This study not only confirms the presence of gut microbiomes that contribute differently to locomotion, but also explains the mixed results in research on the association between the gut microbiome and locomotion.

Fecal Microbiome Does Not Represent Whole Gut Microbiome

The current gut microbiome research relies on the fecal microbiome under the assumption that the fecal microbiome represents the microbiome of the entire gastrointestinal (GI) tract. However, there have been growing concerns about using feces as a proxy to study the gut microbiome. Here, we comprehensively analyzed the composition of microbiome and metabolites in the feces and at 14 different locations of GI tracts of genetically homogenous sibling pigs to evaluate the validity of using feces as a proxy to the whole gut microbiome. The composition of intestinal microbes constituting the gut microbiome at each intestinal content and feces and their metabolic compositions were thoroughly investigated through metagenome sequencing and an ultraperformance LC-MS/MS, respectively. The fluctuation in the composition of the microbiome in the stomach and the small intestine became stabilized from the large intestine to feces and was able to be categorized into 3 groups. The taxonomic α-diversities measured by ACE (abundance-based coverage estimator) richness and Shannon diversity indicated that the microbiome in the large intestine was much more diverse than those of the small intestine and feces. The highly independent intestinal microbes in the stomach and the small intestine became flourished in the large intestine and converged into a community with tightly connected networks. β-Diversity analyses by NMDS plots, PCA, and unsupervised hierarchical clustering all showed that the diversities of microbiome compositions were lowest in feces while highest in the large intestine. In accordance with fluctuation of the composition of gut microbiome along with the GI tract, the metabolic composition also completely differed in a location-specific manner along with the GI tract. Comparative analysis of the fecal microbiome and metabolites with those of the whole GI tract indicated that fecal microbiome is insufficient to represent the whole gut microbiome.

The effect of probiotic and synbiotic supplementation on appetite-regulating hormones and desire to eat: A systematic review and meta-analysis of clinical trials

Recent studies have demonstrated the effect of probiotics, prebiotics, and synbiotics on adiponectin and leptin levels; however, those findings remain contested. The present study aimed to explore the impact of probiotics/synbiotics on appetite-regulating hormones and the desire to eat.

METHODS

A systematic review was conducted by searching the Medline (PubMed) and Scopus databases from inception to December 2021, using relevant keywords and MeSH terms, and appropriate randomized controlled trials (RCTs) were extracted. The standardized mean differences (SMD) and 95% confidence intervals (95%CIs) were calculated as part of the meta-analysis using a random-effect model to determine the mean effect sizes. Analysis of Galbraith plots and the Cochrane Chi-squared test were conducted to examine heterogeneity.

RESULTS

Meta-analysis of data from a total of 26 RCTs (n = 1536) showed a significant decrease in serum/plasma leptin concentration following probiotic/synbiotic supplementation (SMD: -0.38, 95%CI= -0.638, -0.124); P-value= 0.004; I²= 69.4%; P heterogeneity < 0.001). The leptin level decrease from probiotic/synbiotic supplementation was higher in patients with NAFLD than those with overweight/obesity or type 2 diabetes mellitus/ metabolic syndrome/ prediabetes. Probiotic/synbiotic supplementation was associated with a trending increase in adiponectin levels, stronger in patients with type 2 diabetes mellitus, metabolic syndrome, and prediabetes (SMD: 0.25, 95%CI= 0.04, 0.46) µg/mL; P-value= 0.021; I² = 16.8%; P heterogeneity= 0.30). Additionally, supplementation with probiotic/synbiotic was linked to a slight increase in desire to eat (SMD: 0.34, 95%CI= 0.03, 0.66) P-value = 0.030; I² = 39.4%; P heterogeneity= 0.16).

CONCLUSION

Our meta-analysis indicates a favorable impact of probiotic/synbiotic supplementation on regulating leptin and adiponectin secretion.

The effect of probiotic and synbiotic supplementation on lipid parameters among patients with cardiometabolic risk factors: a systematic review and meta-analysis of clinical trials

Although the available evidence emphasizes the beneficial effects of probiotics in normalizing various cardiometabolic markers, there is still substantial uncertainty in this regard. Thus, we set out to determine the effect sizes of probiotics on blood lipid parameters more coherently. A systematic literature search of the Medline (PubMed) and Scopus databases was conducted from inception to February 12, 2021, applying both MeSH terms and free text terms to find the relevant randomized controlled trials (RCTs). The meta-analysis was conducted based on a random-effect model to calculate the mean effect sizes demonstrated as weighted mean differences (WMD) and the 95% confidence intervals (95%CI). To explore the heterogeneity, the Cochrane Chi-squared test, and analysis of Galbraith plots were performed. Meta-analysis of data from 40 RCTs (n = 2795) indicated a significant decrease in serum/plasma triglyceride (WMD (95%CI)    -12.26 (-17.11- -7.41) mg/dL; P-value <0.001; I2 (%)= 29.9; P heterogeneity = 0.034)), total cholesterol (with high heterogeneity) (WMD (95%CI)    -8.43 (-11.90- -4.95) mg/dL; P-value <0.001; I2 (%) =56.8; P heterogeneity < 0.001), LDL-C (WMD (95%CI)    -5.08 (-7.61, -2.56) mg/dL; P-value <0.001; I2 (%) =42.7; P heterogeneity =0.002), and HDL-C (with high heterogeneity) (WMD (95%CI)    1.14 (0.23, 2.05) mg/dL; P-value =0.014; I2 (%) = 59.8; P heterogeneity < 0.001) following receiving probiotic/synbiotic supplements. Collectively, the current preliminary evidence supports the effectiveness of probiotics/synbiotics in improving dyslipidemia and various lipid parameters more prominently among subjects with hyperlipidemia, diabetes, and metabolic syndrome. However, large and well conducted RCTs are required to provide further convincing support for these results.

A Novel Bacterium, Butyricimonas virosa, Preventing HFD-Induced Diabetes and Metabolic Disorders in Mice via GLP-1 Receptor

Knowledge of the impact of the gut microbiota on human health has increased, and modulation of the bacterial community is now considered a therapeutic target for various diseases. Certain novel bacterial species have probiotic properties associated with improvement in obesity and related metabolic disorders. The relative abundance of Butyricimonas spp. is correlated with metabolic parameters; however, the physiological role of Butyricimonas in metabolic improvement is unclear. In this study, live and heat-killed Butyricimonas virosa were administered to mice with high-fat diet (HFD)-induced obesity. Both live and heat-killed B. virosa ameliorated HFD-impaired body weight, serum glucose level, insulin resistance, and liver steatosis. Moreover, activation of the glucagon-like peptide-1 receptor (GLP-1R) and peroxisome proliferator-activated receptor α (PPARα) was observed in the liver, and the expression levels of insulin receptor substrate (IRS)-1, IRS-2, Toll-like receptor 5 (TLR5), and zonula occludens-1 (ZO-1) were upregulated in the ileum. Finally, we demonstrated that the effect of B. virosa treatment on glucose regulation may be linked to the upregulation of GLP-1R in the liver and is not a result of colonization of the gut by B. virosa or B. virosa-produced butyrate. Our results provide a rationale for the development of Butyricimonas spp.-based therapeutics and prophylactics for hyperglycemia.

Comparative Analysis of Original and Replaced Gut Microbiomes within Same Individuals Identified the Intestinal Microbes Associated with Weight Gaining

The precise mechanisms of action of the host’s gut microbiome at the level of its constituting bacteria are obscure in most cases despite its definitive role. To study the precise role of the gut microbiome on the phenotypes of a host by excluding host factors, we analyzed two different gut microbiomes within the same individual mouse after replacing the gut microbiome with a new one to exclude the host factors. The gut microbiome of conventional C57BL/6 mice was randomly reestablished by feeding fecal samples from obese humans to the mice, and depleting their original gut microbiome with an antibiotic and antifungal treatment. Comparison of body weight changes before and 3 months after the replacement of the gut microbiome showed that the gut microbiome replacement affected the body weight gain in three different ways: positive, medium, and negative. The differences in body weight gain were associated with establishment of a different kind of gut microbiome in each of the mice. In addition, body weight gaining was negatively associated with the Firmicutes/Bacteroidetes ratio, which is consistent with previous recent findings. Thorough statistical analysis at low taxonomic levels showed that uncultured bacteria NR_074436.1, NR_144750.1, and NR_0421101.1 were positively associated with body weight gain, while Trichinella pseudospiralis and uncultured bacteria NR_024815.1 and NR_144616.1 were negatively associated. This work shows that replacement of the gut microbiome within the same individual provides an excellent opportunity for the purpose of gut microbiome analysis by excluding the host factors.

The Effects of Probiotics on Inflammation, Endothelial Dysfunction, and Atherosclerosis Progression: A Mechanistic Overview

INTRODUCTION

The relationship between the intestinal microbiota dysbiosis, inflammation, and cardiovascular disorders (CVDs) has become evident, based on a growing body of literature from animal models and human studies. On the other hand, probiotics are believed to have promising effects on modifying dysbiosis and protecting against CVDs.

OBJECTIVE

This narrative review provides an overview of the link between gut microbiota, inflammation, endothelial dysfunction, and atherosclerosis. The influences of probiotic supplementation on biomarkers contributing to these conditions as the primary underlying risk factors for developing CVDs are also discussed.

METHODS

An up-to-date review was performed of the available evidence from experimental studies, clinical trials, and meta-analyses, considering their challenges and limitations. It also aimed to provide mechanistic insight into the likely mechanisms of probiotics that could prevent atherosclerosis initiation and progression.

RESULTS

Probiotic supplementation seems to be associated with reduced levels of inflammation and oxidative stress biomarkers (C-reactive protein, tumour necrosis factor-α, interleukin (IL)-6, IL-12, and malondialdehyde). Further, these agents might enhance antioxidant factors (IL-10, total antioxidant status, total antioxidant capacity, glutathione, and nitric oxide). Probiotics also appear to improve intestinal barrier integrity, reduce leakage of harmful metabolites (e.g., lipopolysaccharides), inhibit pro-inflammatory signalling pathways, and possibly suppress the formation of trimethylamine/trimethylamine oxide. Probiotics have also been found to enhance endothelial function and halter thrombosis.

CONCLUSION

The current clinical evidence underlines belief that probiotics might be associated with reduced levels of inflammation biomarkers. Experimental evidence reports that the beneficial effects of probiotics seem to be mainly imposed by triggering the secretion of short-chain fatty acids and bile acids, in addition to suppressing the NF-κB signalling pathway. However, the current studies are still in their infancy and it is of high priority to design further research on the topic.

Effect of chronic restraint stress and western-diet feeding on colonic regulatory gene expression in mice

BACKGROUND

Diet-induced obesity (DIO) and psychological stress are significant independent regulators of gastrointestinal physiology; however, our understanding of how these two disorders influence the host-microbe interface is still poorly characterized. The aim of this study was to assess the combined influences of diet-induced obesity and psychological stress on microbiome composition and colonic gene expression.

METHODS

C57BL/6J mice (n = 48) were subject to a combination of 22 weeks of Western diet (WD) feeding and a chronic restraint stressor (CRS) for the last 4 weeks of feeding. At the end of the combined intervention, microbiome composition was determined from cecal contents, and colonic tissue gene expression was assessed by multiplex analysis using NanoString nCounter System and real-time qPCR.

RESULTS

WD feeding induced a DIO phenotype with increased body weight, worsened metabolic markers, and alterations to microbiome composition. CRS reduced body weight in both dietary groups while having differential effects on glucose metabolism. CRS improved the Firmicutes/Bacteroidetes ratio in WD-fed animals while expanding the Proteobacteria phyla. Significantly lower expression of colonic Tlr4 (p = 0.008), Ocln (p = 0.004), and Cldn3 (p = 0.004) were noted in WD-fed animals compared to controls with no synergistic effects observed when combined with CRS. No changes to colonic expression of downstream inflammatory mediators were observed. Interestingly, higher levels of expression of Cldn2 (p = 0.04) and bile acid receptor Nr1h4 (p = 0.02) were seen in mice exposed to CRS.

CONCLUSION

Differential but not synergistic effects of WD and CRS were noted at the host-microbe interface suggesting multifactorial responses that require further investigation.

Treatment of Hyperammonemia by Transplanting a Symbiotic Pair of Intestinal Microbes

Hyperammonemia is a deleterious and inevitable consequence of liver failure. However, no adequate therapeutic agent is available for hyperammonemia. Although recent studies showed that the pharmabiotic approach could be a therapeutic option for hyperammonemia, its development is clogged with poor identification of etiological microbes and low transplantation efficiency of candidate microbes. In this study, we developed a pharmabiotic treatment for hyperammonemia that employs a symbiotic pair of intestinal microbes that are both able to remove ammonia from the surrounding environment. By a radioactive tracing experiment in mice, we elucidated how the removal of ammonia by probiotics in the intestinal lumen leads to lower blood ammonia levels. After determination of the therapeutic mechanism, ammonia-removing probiotic strains were identified by high-throughput screening of gut microbes. The symbiotic partners of ammonia-removing probiotic strains were identified by screening intestinal microbes of a human gut, and the pairs were administrated to hyperammonemic mice to evaluate therapeutic efficacy. Blood ammonia was in a chemical equilibrium relationship with intestinal ammonia. Lactobacillus reuteri JBD400 removed intestinal ammonia to shift the chemical equilibrium to lower the blood ammonia level. L. reuteri JBD400 was successfully transplanted with a symbiotic partner, Streptococcus rubneri JBD420, improving transplantation efficiency 2.3×10³ times more compared to the sole transplantation while lowering blood ammonia levels significantly. This work provides new pharmabiotics for the treatment of hyperammonemia as well as explains its therapeutic mechanism. Also, this approach provides a concept of symbiotic pairs approach in the emerging field of pharmabiotics.

Host Factors Affect the Gut Microbiome More Significantly than Diet Shift

The determining factors of the composition of the gut microbiome are one of the main interests in current science. In this work, we compared the effect of diet shift (DS) from heavily relying on meatatarian diets to vegetarian diets and physical exercise (EX) on the composition of the gut microbiome after 3 months. Although both DS and EX affected the composition of the gut microbiome, the patterns of alteration were different. The α-diversity analyzed by InvSimpson, Shannon, Simpson, and Evenness showed that both EX and DS affected the microbiome, causing it to become more diverse, but EX affected the gut microbiome more significantly than DS. The β-diversity analyses indicated that EX and DS modified the gut microbiome in two different directions. Co-occurrence network analysis confirmed that both EX and DS modified the gut microbiome in different directions, although EX modified the gut microbiome more significantly. Most notably, the abundance of Dialister succinatiphilus was upregulated by EX, and the abundances of Bacteroides fragilis, Phascolarctobacterium faecium, and Megasphaera elsdenii were downregulated by both EX and DS. Overall, EX modulated the composition of the gut microbiome more significantly than DS, meaning that host factors are more important in determining the gut microbiome than diets. This work also provides a new theoretical basis for why physical exercise is more health-beneficial than vegetarian diets.

The regional diversity of gut microbiome along the GI tract of male C57BL/6 mice

BACKGROUND

The proliferation and survival of microbial organisms including intestinal microbes are determined by their surrounding environments. Contrary to popular myth, the nutritional and chemical compositions, water contents, O2 contents, temperatures, and pH in the gastrointestinal (GI) tract of a human are very different in a location-specific manner, implying heterogeneity of the microbial composition in a location-specific manner.

RESULTS

We first investigated the environmental conditions at 6 different locations along the GI tract and feces of ten weeks' old male SPF C57BL/6 mice. As previously known, the pH and water contents of the GI contents at the different locations of the GI tract were very different from each other in a location-specific manner, and none of which were not even similar to those of feces. After confirming the heterogeneous nature of the GI contents in specific locations and feces, we thoroughly analyzed the composition of the microbiome of the GI contents and feces. 16S rDNA-based metagenome sequencing on the GI contents and feces showed the presence of 13 different phyla. The abundance of Firmicutes gradually decreased from the stomach to feces while the abundance of Bacteroidetes gradually increased. The taxonomic α-diversities measured by ACE (Abundance-based Coverage Estimator) richness, Shannon diversity, and Fisher's alpha all indicated that the diversities of gut microbiome at colon and cecum were much higher than that of feces. The diversities of microbiome compositions were lowest in jejunum and ileum while highest in cecum and colon. Interestingly, the diversities of the fecal microbiome were lower than those of the cecum and colon. Beta diversity analyses by NMDS plots, PCA, and unsupervised hierarchical clustering all showed that the microbiome compositions were very diverse in a location-specific manner. Direct comparison of the fecal microbiome with the microbiome of the whole GI tracts by α-and β-diversities showed that the fecal microbiome did not represent the microbiome of the whole GI tract.

CONCLUSION

The fecal microbiome is different from the whole microbiome of the GI tract, contrary to a baseline assumption of contemporary microbiome research work.

The Resveratrol Rice DJ526 Callus Significantly Increases the Lifespan of Drosophila (Resveratrol Rice DJ526 Callus for Longevity)

Resveratrol has gained widespread scientific attention due to its ability to significantly extend the lifespan of yeast. However, research on the efficacy of resveratrol on lifespan extension has yielded mixed results in animal studies, making resveratrol a contentious subject. In our previous work, we reported that transgenic resveratrol rice DJ526 showed unusual health benefits beyond expectations. In this work, we established a callus culture of resveratrol rice DJ526, which contains 180 times more resveratrol than the grain, and found that resveratrol rice callus significantly extended the median lifespan of Drosophila melanogaster by up to 50% compared to the control. The resveratrol rice callus also ameliorated age-dependent symptoms, including locomotive deterioration, body weight gain, eye degeneration, and neurodegeneration of D. melanogaster with age progression. Considering that resveratrol is the most preferred antiaging compound due to its superior safety and proven mechanism against many serious adult diseases, the outstanding efficacy of resveratrol on the longevity of wild-type animals could cast a light on the development of antiaging therapeutic agents.

Gut Microbiota and Predicted Metabolic Pathways in a Sample of Mexican Women Affected by Obesity and Obesity Plus Metabolic Syndrome

Obesity is an excessive fat accumulation that could lead to complications like metabolic syndrome. There are reports on gut microbiota and metabolic syndrome in relation to dietary, host genetics, and other environmental factors; however, it is necessary to explore the role of the gut microbiota metabolic pathways in populations like Mexicans, where the prevalence of obesity and metabolic syndrome is high. This study identify alterations of the gut microbiota in a sample of healthy Mexican women (CO), women with obesity (OB), and women with obesity plus metabolic syndrome (OMS). We studied 67 women, characterizing their anthropometric and biochemical parameters along with their gut bacterial diversity by high-throughput DNA sequencing. Our results indicate that in OB or OMS women, Firmicutes was the most abundant bacterial phylum. We observed significant changes in abundances of bacteria belonging to the Ruminococcaceae, Lachnospiraceae, and Erysipelotrichaceae families and significant enrichment of gut bacteria from 16 different taxa that might explain the observed metabolic alterations between the groups. Finally, the predicted functional metagenome of the gut microbiota found in each category shows differences in metabolic pathways related to lipid metabolism. We demonstrate that Mexican women have a particular bacterial gut microbiota characteristic of each phenotype. There are bacteria that potentially explain the observed metabolic differences between the groups, and gut bacteria in OMS and OB conditions carry more genes of metabolic pathways implicated in lipid metabolism.

Probiotics in human health and disease: from nutribiotics to pharmabiotics

Probiotics are the most useful tools for balancing the gut microbiota and thereby influencing human health and disease. Probiotics have a range of effects, from those on nutritional status to medical conditions throughout the body from the gut to non-intestinal body sites such as the brain and skin. Research interest in probiotics with nutritive claims (categorized as nutribiotics) has evolved into interest in therapeutic and pharmacological probiotics with health claims (pharmabiotics). The concept of pharmabiotics emerged only two decades ago, and the new categorization of probiotics to nutribiotics and pharmabiotics was recently suggested, which are under the different regulation depending on that they are food or drug. Information of the gut microbiome has been continuously accumulating, which will make possible the gut microbiome-based healthcare in the future, when nutribiotics show potential for maintaining health while pharmabiotics are effective therapeutic tools for human diseases. This review describes the current understanding in the conceptualization and classification of probiotics. Here, we reviewed probiotics as nutribiotics with nutritional functions and pharmabiotics with pharmaceutic functions in different diseases.

Microbiota and metabolic diseases

The microbiota is a complex ecosystem of microorganisms consisting of bacteria, viruses, protozoa, and fungi, living in different districts of the human body, such as the gastro-enteric tube, skin, mouth, respiratory system, and the vagina. Over 70% of the microbiota lives in the gastrointestinal tract in a mutually beneficial relationship with its host. The microbiota plays a major role in many metabolic functions, including modulation of glucose and lipid homeostasis, regulation of satiety, production of energy and vitamins. It exerts a role in the regulation of several biochemical and physiological mechanisms through the production of metabolites and substances. In addition, the microbiota has important anti-carcinogenetic and anti-inflammatory actions. There is growing evidence that any modification in the microbiota composition can lead to several diseases, including metabolic diseases, such as obesity and diabetes, and cardiovascular diseases. This is because alterations in the microbiota composition can cause insulin resistance, inflammation, vascular, and metabolic disorders. The causes of the microbiota alterations and the mechanisms by which microbiota modifications can act on the development of metabolic and cardiovascular diseases have been reported. Current and future preventive and therapeutic strategies to prevent these diseases by an adequate modulation of the microbiota have been also discussed.