Novel Insight into the Effect of Probiotics in the Regulation of the Most Important Pathways Involved in the Pathogenesis of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is considered one of the most common disorders worldwide. Although several treatment modalities have been developed, the existing interventions have not yielded the desired results. Therefore, researchers have focused on finding treatment choices with low toxicity and few adverse effects that could control T2DM efficiently. Various types of research on the role of gut microbiota in developing T2DM and its related complications have led to the growing interest in probiotic supplementation. Several properties make these organisms unique in terms of human health, including their low cost, high reliability, and good safety profile. Emerging evidence has demonstrated that three of the most important signaling pathways, including nuclear factor kappa B (NF-κB), phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), and nuclear factor erythroid 2-related factor 2 (Nrf2), which involved in the pathogenesis of T2DM, play key functions in the effects of probiotics on this disease. Hence, we will focus on the clinical applications of probiotics in the management of T2DM. Then, we will also discuss the roles of the involvement of various probiotics in the regulation of the most important signaling pathways (NF-κB, PI3K/Akt, and Nrf2) involved in the pathogenesis of T2DM.

The Symbiosis Between Lactobacillus acidophilus and Inulin: Metabolic Benefits in an Obese Murine Model

Obesity is defined as having an excess of adipose tissue and is associated with the development of diabetes, hypertension, and atherosclerosis, which are the main causes of death worldwide. Research shows that probiotics and prebiotics reduce the metabolic alterations caused by high-fat diets. Therefore, this work evaluated the effect of the incorporation of Lactobacillus acidophilus (probiotic) and inulin (prebiotic) in the diet through obesity markers (biochemical, anthropometric, and molecular markers) in an obese murine model. Four treatments were administered: (1) hypocaloric diet (HD), (2) HD + L. acidophilus, (3) HD + inulin, and (4) DH supplemented with L. acidophilus + inulin for 8 weeks. After treatment, glucose, triglycerides, total cholesterol, HDL-C, and LDL-C in plasma were determined. In addition, the total body weight and adipose tissue were taken to calculate the body mass index. Following RNA extraction from adipose tissue, the expression of PPAR gamma, PPAR alpha, and transforming growth factor beta 1 (TGF1β) was evaluated by semiquantitative PCR. All treatments showed an improvement in biochemical markers compared to the values of the obese model (p < 0.05). Optimal values for blood glucose (133.2 ± 14.3 mg/dL), triglycerides (71 ± 4.6 mg/dL), total cholesterol (48.9 ± 6 mg/dL), HDL-C (40.9 ± 4.8 mg/dL), and LDL-C (8.4 ± 1.7 mg/dL) were obtained in the mixed treatment. Regarding fat mass index (FMI), prebiotic treatment caused the greatest reduction. On the other hand, mixed treatment increased the gene expression of PPARα and TGF1β in adipose tissue with DH with L. acidophilus and inulin treatment. This work demonstrates that the use of L. acidophilus and inulin as a complementary treatment is a viable alternative for prevention and action as a complementary treatment for obesity given the reduction in biochemical parameters and anthropometric indices; these reductions were greater than those found in the classic treatment of obesity due to the induction of the expression of genes related to lipid metabolism and anti-inflammatory cytokines, which contribute to reducing the high levels of glucose, triglycerides, and cholesterol caused by obesity.

From Gut to Glucose: A Comprehensive Review on Functional Foods and Dietary Interventions for Diabetes Management

BACKGROUND

In the realm of diabetes research, considerable attention has been directed toward elucidating the intricate interplay between the gastrointestinal tract and glucose regulation. The gastrointestinal tract, once exclusively considered for its role in digestion and nutrient assimilation, is presently acknowledged as a multifaceted ecosystem with regulatory supremacy over metabolic homeostasis and glucose metabolism. Recent studies indicate that alterations in the composition and functionality of the gut microbiota could potentially influence the regulation of glucose levels and glucose homeostasis in the body. Dysbiosis, characterized by perturbations in the equilibrium of gut microbial constituents, has been irrevocably linked to an augmented risk of diabetes mellitus (DM). Moreover, research has revealed the potential influence of the gut microbiota on important factors, like inflammation and insulin sensitivity, which are key contributors to the onset and progression of diabetes. The key protagonists implicated in the regulation of glucose encompass the gut bacteria, gut barrier integrity, and the gut-brain axis. A viable approach to enhance glycemic control while concurrently mitigating the burden of comorbidities associated with diabetes resides in the strategic manipulation of the gut environment through adapted dietary practices.

OBJECTIVE

This review aimed to provide a deep understanding of the complex relationship between gut health, glucose metabolism, and diabetes treatment.

CONCLUSION

This study has presented an exhaustive overview of dietary therapies and functional foods that have undergone extensive research to explore their potential advantages in the management of diabetes. It looks into the role of gut health in glucose regulation, discusses the impact of different dietary elements on the course of diabetes, and evaluates how well functional foods can help with glycemic control. Furthermore, it investigates the mechanistic aspects of these therapies, including their influence on insulin sensitivity, β-cell activity, and inflammation. It deliberates on the limitations and potential prospects associated with integrating functional foods into personalized approaches to diabetes care.

The Intervention of Probiotics on Type 2 Diabetes Mellitus in Animal Models

Type 2 diabetes accounts for more than 90% of diabetes patients with the incidence and prevalence continuously rising globally. As a prospective therapy strategy for type 2 diabetes, probiotics have shown beneficial effects both in animal experiments and human clinical trials. This review summarizes the commonly used animal models in probiotic intervention research and presents the evidence and mechanism of diabetes intervention with probiotics in these animal models. Probiotics can help maintain glucose homeostasis, improve lipid metabolism, promote the production of short-chain fatty acids, and reduce inflammatory reactions in animal models. However, the clinical translation of benefits from probiotics is still challenged by intrinsic differences between experimental animal models and humans, and the application of humanized non-rodent diabetic animal models may contribute to the clinical translation of probiotics in the future.

Probiotic and prebiotic supplementation ameliorates chronic restraint stress-induced male reproductive dysfunction

Restraint stress (RS) can induce male reproductive deficits by activating the hypothalamic-pituitary-adrenal (HPA) axis and causing oxidative stress. Previous studies have shown that probiotics can alleviate neurological and metabolic disorders induced by stress. However, the effects of probiotics on RS-induced reproductive deficits have not been fully elucidated. This study aimed to investigate whether Lactobacillus rhamnosus NCDC-610 (Probiotic-1) and Lactobacillus fermentum NCDC-400 (Probiotic-2) with prebiotic (fructooligosaccharides (FOS)) could prevent RS-induced reproductive deficits. C57BL6/J mice were subjected to RS for four hours daily before oral administration of probiotics (4 × 109 CFU per mice) either separately or concurrently with FOS. The results showed that oral administration of Probiotic-1 and Probiotic-2 protected against RS-induced sperm deficits, including sperm count, motility, morphology, and histopathology of testes, and improved intestinal health. Furthermore, Probiotic-1 and Probiotic-2 prevented RS-induced changes in testosterone levels by up-regulating the expressions of steroidogenic acute regulatory protein (StAR), cytochrome P450 side-chain cleavage enzyme (P450scc), and 17β-hydroxysteroid dehydrogenase (17βHSD) in the testes. Additionally, Probiotic-1 and Probiotic-2 increased the activities of catalase and superoxide dismutase and reduced the fold change of interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor-alpha (TNF-α), indicating a protective effect against RS-induced oxidative stress. Oral administration of Probiotic-1 and Probiotic-2, either separately or concurrently with FOS (probiotic dose of 4 × 109 CFU per mice and prebiotic 5% w/v), prevented RS-induced activation of the HPA axis and improved male fertility. These findings suggest that L. rhamnosus NCDC-610 and L. fermentum NCDC-400 are safe and effective probiotics for mitigating stress-induced male reproductive deficits.

Screening for potential novel probiotic Levilactobacillus brevis RAMULAB52 with antihyperglycemic property from fermented Carica papaya L

Probiotics are live microorganisms with various health benefits when consumed in appropriate amounts. Fermented foods are a rich source of these beneficial organisms. This study aimed to investigate the probiotic potential of lactic acid bacteria (LAB) isolated from fermented papaya (Carica papaya L.) through in vitro methods. The LAB strains were thoroughly characterized, considering their morphological, physiological, fermentative, biochemical, and molecular properties. The LAB strain's adherence and resistance to gastrointestinal conditions, as well as its antibacterial and antioxidant capabilities, were examined. Moreover, the strains were tested for susceptibility against specific antibiotics, and safety evaluations encompassed the hemolytic assay and DNase activity. The supernatant of the LAB isolate underwent organic acid profiling (LCMS). The primary objective of this study was to assess the inhibitory activity of α-amylase and α-glucosidase enzymes, both in vitro and in silico. Gram-positive strains that were catalase-negative and carbohydrate fermenting were selected for further analysis. The LAB isolate exhibited resistance to acid bile (0.3% and 1%), phenol (0.1% and 0.4%), and simulated gastrointestinal juice (pH 3-8). It demonstrated potent antibacterial and antioxidant abilities and resistance to kanamycin, vancomycin, and methicillin. The LAB strain showed autoaggregation (83%) and adhesion to chicken crop epithelial cells, buccal epithelial cells, and HT-29 cells. Safety assessments indicated no evidence of hemolysis or DNA degradation, confirming the safety of the LAB isolates. The isolate's identity was confirmed using the 16S rRNA sequence. The LAB strain Levilactobacillus brevis RAMULAB52, derived from fermented papaya, exhibited promising probiotic properties. Moreover, the isolate demonstrated significant inhibition of α-amylase (86.97%) and α-glucosidase (75.87%) enzymes. In silico studies uncovered that hydroxycitric acid, one of the organic acids derived from the isolate, interacted with crucial amino acid residues of the target enzymes. Specifically, hydroxycitric acid formed hydrogen bonds with key amino acid residues, such as GLU233 and ASP197 in α-amylase, and ASN241, ARG312, GLU304, SER308, HIS279, PRO309, and PHE311 in α-glucosidase. In conclusion, Levilactobacillus brevis RAMULAB52, isolated from fermented papaya, possesses promising probiotic properties and exhibits potential as an effective remedy for diabetes. Its resistance to gastrointestinal conditions, antibacterial and antioxidant abilities, adhesion to different cell types, and significant inhibition of target enzymes make it a valuable candidate for further research and potential application in the field of probiotics and diabetes management.

The effects of probiotic administration on patients with prediabetes: a meta-analysis and systematic review

BACKGROUND

This paper aimed to examine the effects of probiotics on eight factors in the prediabetic population by meta-analysis, namely, fasting blood glucose (FBG), glycated haemoglobin A1c (HbA1c), homeostatic model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), and the mechanisms of action are summarized from the existing studies.

METHODS

Seven databases (PubMed, Web of Science, Embase, Cochrane Library, SinoMed, CNKI, and Wanfang Med) were searched until March 2022. Review Manager 5.4 was used for meta-analysis. The data were analysed using weighted mean differences (WMDs) or standardized mean differences (SMDs) under a fixed effect model to observe the efficacy of probiotic supplementation on the included indicators.

RESULTS

Seven publications with a total of 460 patients were included. According to the meta-analysis, probiotics were able to significantly decrease the levels of HbA1c (WMD, -0.07; 95% CI -0.11, -0.03; P = 0.001), QUICKI (WMD, 0.01; 95% CI 0.00, 0.02; P = 0.04), TC (SMD, -0.28; 95% CI -0.53, -0.22; P = 0.03), TG (SMD, -0.26; 95% CI -0.52, -0.01; P = 0.04), and LDL-C (WMD, -8.94; 95% CI -14.91, -2.97; P = 0.003) compared to levels in the placebo group. The effects on FBG (WMD, -0.53; 95% CI -2.31, 1.25; P = 0.56), HOMA-IR (WMD, -0.21; 95% CI -0.45, 0.04; P = 0.10), and HDL-C (WMD, 2.05; 95% CI -0.28, 4.38; P = 0.08) were not different from those of the placebo group.

CONCLUSION

The present study clearly indicated that probiotics may fulfil an important role in the regulation of HbA1c, QUICKI, TC, TG and LDL-C in patients with prediabetes. In addition, based on existing studies, we concluded that probiotics may regulate blood glucose homeostasis in a variety of ways.

TRIAL REGISTRATION

This meta-analysis has been registered at PROSPERO with ID: CRD42022321995.

Maltooligosaccharide forming amylases and their applications in food and pharma industry

Oligosaccharides are low molecular weight carbohydrates with a wide range of health benefits due to their excellent bio-preservative and prebiotic properties. The popularity of functional oligosaccharides among modern consumers has resulted in impressive market demand. Organoleptic and prebiotic properties of starch-derived oligosaccharides are advantageous to food quality and health. The extensive health benefits of oligosaccharides offered their applications in the food, pharmaceuticals, and cosmetic industry. Maltooligosaccharides and isomaltooligosaccharides comprise 2-10 glucose units linked by α-1-4 and α-1-6 glycoside bonds, respectively. Conventional biocatalyst-based oligosaccharides processes are often multi-steps, consisting of starch gelatinization, hydrolysis and transglycosylation. With higher production costs and processing times, the current demand cannot meet on a large-scale production. As a result, innovative and efficient production technology for oligosaccharides synthesis holds paramount importance. Malto-oligosaccharide forming amylase (EC 3.2.1.133) is one of the key enzymes with a dual catalytic function used to produce oligosaccharides. Interestingly, Malto-oligosaccharide forming amylase catalyzes glycosidic bond for its transglycosylation to its inheritance hydrolysis and alternative biocatalyst to the multistep technology. Genetic engineering and reaction optimization enhances the production of oligosaccharides. The development of innovative and cost-effective technologies at competitive prices becomes a national priority.

The Mechanisms of the Potential Probiotic Lactiplantibacillus plantarum against Cardiovascular Disease and the Recent Developments in its Fermented Foods

Cardiovascular disease (CVD) has become the leading cause of death worldwide. Many recent studies have pointed out that Lactiplantibacillus plantarum (Lb. plantarum) has great potential in reducing the risk of CVD. Lb. plantarum is a kind of lactic acid bacteria (LAB) widely distributed in fermented food and the human intestinal tract, some strains of which have important effects on human health and the potential to be developed into probiotics. In this review, we summarize the mechanism of potential probiotic strains of Lb. plantarum against CVD. It could regulate the body’s metabolism at the molecular, cellular, and population levels, thereby lowering blood glucose and blood lipids, regulating blood pressure, and ultimately reducing the incidence of CVD. Furthermore, since Lb. plantarum is widely utilized in food industry, we highlight some of the most important new developments in fermented food for combating CVD; providing an insight into these fermented foods can assist scientists in improving the quality of these foods as well as alleviating patients’ CVD symptoms. We hope that in the future functional foods fermented by Lb. plantarum can be developed and incorporated into the daily diet to assist medication in alleviating CVD to some extent, and maintaining good health.

Probiotic Mechanisms Affecting Glucose Homeostasis: A Scoping Review

The maintenance of a healthy status depends on the coexistence between the host organism and the microbiota. Early studies have already focused on the nutritional properties of probiotics, which may also contribute to the structural changes in the gut microbiota, thereby affecting host metabolism and homeostasis. Maintaining homeostasis in the body is therefore crucial and is reflected at all levels, including that of glucose, a simple sugar molecule that is an essential fuel for normal cellular function. Despite numerous clinical studies that have shown the effect of various probiotics on glucose and its homeostasis, knowledge about the exact function of their mechanism is still scarce. The aim of our review was to select in vivo and in vitro studies in English published in the last eleven years dealing with the effects of probiotics on glucose metabolism and its homeostasis. In this context, diverse probiotic effects at different organ levels were highlighted, summarizing their potential mechanisms to influence glucose metabolism and its homeostasis. Variations in results due to different methodological approaches were discussed, as well as limitations, especially in in vivo studies. Further studies on the interactions between probiotics, host microorganisms and their immunity are needed.

The Relationships between Gut Microbiota and Diabetes Mellitus, and Treatments for Diabetes Mellitus

Diabetes mellitus is considered to be a global epidemic. The combination of genetic susceptibility and an unhealthy lifestyle is considered to be the main trigger of this metabolic disorder. Recently, there has been increased interest in the roles of gut microbiota as a new potential contributor to this epidemic. Research, in recent years, has contributed to an in-depth characterization of the human microbiome and its associations with various diseases, including metabolic diseases and diabetes mellitus. It is known that diet can change the composition of gut microbiota, but it is unclear how this, in turn, may influence metabolism. The main objective of this review is to evaluate the pathogenetic association between microbiota and diabetes and to explore any new therapeutic agents, including nutraceuticals that may modulate the microbiota. We also look at several mechanisms involved in this process. There is a clear, bidirectional relationship between microbiota and diabetes. Current treatments for diabetes influence microbiota in various ways, some beneficial, but others with still unclear effects. Microbiota-aimed treatments have seen no real-world significant effects on the progression of diabetes and its complications, with more studies needed in order to find a really beneficial agent.

Possible Benefits of Faecalibacterium prausnitzii for Obesity-Associated Gut Disorders

Metabolic disorders are an increasing concern in the industrialized world. Current research has shown a direct link between the composition of the gut microbiota and the pathogenesis of obesity and diabetes. In only a few weeks, an obesity-inducing diet can lead to increased gut permeability and microbial dysbiosis, which contributes to chronic inflammation in the gut and adipose tissues, and to the development of insulin resistance. In this review, we examine the interplay between gut inflammation, insulin resistance, and the gut microbiota, and discuss how some probiotic species can be used to modulate gut homeostasis. We focus primarily on Faecalibacterium prausnitzii, a highly abundant butyrate-producing bacterium that has been proposed both as a biomarker for the development of different gut pathologies and as a potential treatment due to its production of anti-inflammatory metabolites.

Melatonin-primed ADMSCs elicit an efficacious therapeutic response in improving high-fat diet induced non-alcoholic fatty liver disease in C57BL/6J mice

Background

Stem cells are widely used for therapy including treatment of liver damage. Adipose-derived mesenchymal stem cells (ADMSCs) administered to treat fatty liver are known to improve liver function but their use is restricted due to a poor success rate. This study investigates efficacy of melatonin-primed ADMSCs (Mel. MSCs) in experimentally induced non-alcoholic fatty liver disease (NAFLD).

Results

MSCs treated with LPS showed prominent DCFDA fluorescence as compared to the untreated cells. Also, the JC-1 staining had accounted for higher intensity of green monomer and a weak fluorescence of red dimer indicating weaker mitochondrial membrane potential. But melatonin co-treatment could make necessary corrective changes as evidenced by reverse set of results. The overall cell survival was also found to be improved following melatonin treatment as evidenced by the MTT assay. Also, the antioxidant (Nrf2 and Ho-1) and anti-inflammatory genes (Il-4 and Il-10) showed a decrement in their mRNA levels following LPS treatment whereas the pro-inflammatory genes (Tnf-α, Il-6, Tlr-4, and Lbp) showed a reciprocal increment in the said group. Melatonin co-treatment accounted for an improved status of antioxidant and anti-inflammatory genes as evidenced by their mRNA levels. High-fat high-fructose diet (HFFD) fed C57BL/6J mice recorded higher serum AST and ALT levels and fatty manifestation in histology of liver along with lowered mRNA levels of antioxidant (Nrf2, Catalase, and Gss) genes and Hgf. These set of parameters showed a significant improvement in HFFD + Mel.MSC group.

Conclusion

A significant improvement in viability of MSCs was recorded due to lowered intracellular oxidative stress and improves mitochondrial membrane potential. Further, melatonin-primed MSCs accounted for a significant decrement in fatty manifestations in liver and an improved physiological status of NAFLD in HFFD fed C57BL/6J mice. Taken together, it is hypothesized that melatonin priming to MSCs prior to its use can significantly augment the success of stem cell therapy.

Lactic Acid Bacteria Strains Differently Modulate Gut Microbiota and Metabolic and Immunological Parameters in High-Fat Diet-Fed Mice

Background: Dietary strategies, including the use of probiotics as preventive agents that modulate the gut microbiota and regulate the function of adipose tissue, are suitable tools for the prevention or amelioration of obesity and its comorbidities. We aimed to evaluate the effect of lactic acid bacteria (LAB) with different adipo- and immuno-modulatory capacities on metabolic and immunological parameters and intestinal composition microbiota in high-fat-diet-induced in mice fed a high-fat diet

Methods: Balb/c weaning male mice were fed a standard (SD) or high-fat diet (HFD) with or without supplementation with Limosilactobacillus fermentum CRL1446 (CRL1446), Lactococcus lactis CRL1434 (CRL1434), or Lacticaseibacillus casei CRL431 (CRL431) for 45 days. Biochemical and immunological parameters, white-adipose tissue histology, gut microbiota composition, and ex vivo cellular functionality (adipocytes and macrophages) were evaluated in SD and HFD mice.

Results: CRL1446 and CRL1434 administration, unlike CRL431, induced significant changes in the body and adipose tissue weights and the size of adipocytes. Also, these strains caused a decrease in plasmatic glucose, cholesterol, triglycerides, leptin, TNF-α, IL-6 levels, and an increase of IL-10. The CRL1446 and CRL1434 obese adipocyte in ex vivo functionality assays showed, after LPS stimulus, a reduction in leptin secretion compared to obese control, while with CRL431, no change was observed. In macrophages from obese mice fed with CRL1446 and CRL1434, after LPS stimulus, lower levels of MCP-1, TNF-α, IL-6 compared to obese control were observed. In contrast, CRL431 did not induce modification of cytokine values. Regarding gut microbiota, all strain administration caused a decrease in Firmicutes/Bacteroidetes index and diversity. As well as, related to genus results, all strains increased, mainly the genera Alistipes, Dorea, Barnesiella, and Clostridium XIVa. CRL1446 induced a higher increase in the Lactobacillus genus during the study period.

Conclusions: The tested probiotic strains differentially modulated the intestinal microbiota and metabolic/immunological parameters in high-fat-diet-induced obese mice. These results suggest that CRL1446 and CRL1434 strains could be used as adjuvant probiotics strains for nutritional treatment to obesity and overweight. At the same time, the CRL431 strain could be more beneficial in pathologies that require regulation of the immune system.

Effects of probiotics, prebiotics, and synbiotics on polycystic ovary syndrome: a systematic review and meta-analysis

This meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effects of probiotics, prebiotics, and synbiotics on insulin resistance (IR), lipid profiles, anthropometric indices, and C-reactive protein (CRP) level for polycystic ovary syndrome (PCOS). We searched 8 databases from their inception until 1st October, 2020. The effect sizes were expressed as standardized mean difference (SMD) with 95% confidence intervals (95% CI). Subgroup analyses were undertaken for further identification of effects of probiotics, prebiotics, and synbiotics, based on the following aspects: (1) type of intervention (probiotics, prebiotics, or synbiotics); (2) study duration (≥ 12 weeks or < 12 weeks); (3) number of probiotic strains (multi strains or single strain); (4) probiotic dose (≥ 2 × 10⁸ colony-forming units [CFU] or < 2 × 10⁸ CFU). A total of 17 eligible RCTs with 1049 participants were included. Results showed that probiotic, prebiotic, and synbiotic intake decreased fasting plasma glucose (SMD, -1.35; 95% CI, -2.22 to -0.49; p = 0.002), fasting insulin (SMD, -0.68; 95% CI, -1.08 to -0.27; p = 0.001), homeostatic model of assessment for IR (SMD, -0.73; 95% CI, -1.15 to -0.31; p = 0.001), triglycerides (SMD, -0.85; 95% CI, -1.59 to -0.11; p = 0.024), total cholesterol (SMD, -1.09; 95% CI, -1.98 to -0.21; p = 0.015), low-density lipoprotein cholesterol (SMD, -0.84; 95% CI, -1.64 to -0.03; p = 0.041), very-low-density lipoprotein cholesterol (SMD, -0.44; 95% CI, -0.70 to -0.18; p = 0.001), and increased quantitative insulin sensitivity check index (SMD, 2.00; 95% CI, - 0.79 to 3.22; p = 0.001). However, probiotic, prebiotic, and synbiotic supplements did not affect anthropometric indices, high-density lipoprotein cholesterol, and CRP levels. Subgroup analysis showed that probiotic or prebiotic might be the optimal choice for ameliorating IR or lipid profiles, respectively. Additionally, the effect was positively related to courses and therapeutical dose. Overall, the meta-analysis demonstrates that probiotic, prebiotic, or synbiotic administration is an effective and safe intervention for modifying IR and lipid profiles.

Probiotics, Pre-biotics and Synbiotics in the Treatment of Pre-diabetes: A Systematic Review of Randomized Controlled Trials

Objectives: This study aimed to review the data from randomized controlled trials (RCTs) and identify evidence for microbiota's role and use of probiotics, pre-biotics, or synbiotics in pre-diabetes. Methods: RCTs of pro-, pre-, synbiotics for the treatment of pre-diabetes population will be summarized. We searched for EMBASE, MEDLINE, Web of Science, Cochrane Central, Clinical Trials (ClinicalTrials.gov) from inception to February 2021. Results: The gut microbiota influences host metabolic disorders via the modulation of metabolites, including short-chain fatty acids (SCFAs), the endotoxin lipopolysaccharides (LPS), bile acids (BA) and trimethylamine N-oxide (TMAO), as well as mediating the interaction between the gastrointestinal system and other organs. Due to the limited sources of studies, inconsistent outcomes between included studies. Probiotics can decrease glycated hemoglobin (HbA1c) and have the potential to improve post-load glucose levels. The supplementation of probiotics can suppress the rise of blood cholesterol, but the improvement cannot be verified. Pre-biotics are failed to show an evident improvement in glycemic control, but their use caused the changes in the composition of gut microbiota. A combination of probiotics and pre-biotics in the synbiotics supplementation is more effective than probiotics alone in glycemic control. Conclusion: In the current studies using probiotics, pre-biotics or synbiotics for the treatment of pre-diabetes, the benefits of modulating the abundance of gut microbiota were partially demonstrated. However, there is insufficient evidence to show significant benefits on glucose metabolism, lipid metabolism and body composition.

The effect of probiotics, prebiotics or synbiotics on metabolic outcomes in individuals with diabetes: a systematic review and meta-analysis

AIMS/HYPOTHESIS

The aim was to conduct a systematic review and meta-analysis of randomised controlled clinical trials assessing the effect of probiotic, prebiotic or synbiotic supplementation on gut microbiota and glucose control and lipid levels in individuals with diabetes.

METHODS

MEDLINE, EMBASE and the Cochrane Library were searched. The eligibility criteria for the studies was involvement of participants with a diagnosis of type 1 or type 2 diabetes. Metabolic outcomes (glucose control, insulinaemia, and lipid profile) of any probiotic, prebiotic or synbiotic supplementation related to modification of gut microbiota (prebiotics, probiotics and synbiotics) were analysed. We provided a narrative synthesis and meta-analysis of the findings on metabolic outcomes from the studies. Metabolic outcomes were extracted post-intervention and expressed as mean differences (MDs) and 95% CIs between treatment and comparator groups. We pooled the results using a random-effects meta-analysis. The meta-analysis was conducted using Review Manager (RevMan) software.

RESULTS

After the removal of duplicates and ineligible studies, 5219 studies were retained for review of titles and abstracts. The number of articles was reduced to 130 by review, for which the full-text articles were obtained and reassessed, 38 of which were included in the final meta-analysis. Overall, the use of prebiotics, probiotics or synbiotics reduced HbA_1c levels, but did not reach the threshold for significance (-2.17 mmol/mol, 95% CI -4.37, 0.03; p = 0.05, [-0.20%, 95% CI -0.40 to 0.00; p = 0.05, I² = 66%]) and had no effect on LDL-cholesterol levels (-0.05 mmol/l; 95% CI -0.14, 0.05, p = 0.35, I² = 37%). However, their consumption decreased levels of fasting blood glucose (-0.58 mmol/l; 95% CI -0.86, -0.30; p < 0.01, I² = 60%), total cholesterol (-0.14 mmol/l; 95% CI -0.26, -0.02, p = 0.02, I² = 39%), triacylglycerols (-0.11 mmol/l; 95% CI -0.20, -0.02, p = 0.01, I²= 21%) and insulinaemia (-10.51 pmol/l; 95% CI -16.68,-4.33, p < 0.01, I² = 74%), and increased HDL-cholesterol levels (0.04 mmol/l; 95% CI 0.01, 0.07, p < 0.01, I²= 24%).

CONCLUSIONS/INTERPRETATION

In individuals with diabetes mellitus, supplementation with probiotics, prebiotics or synbiotics improved metabolic variables, although the magnitude of this effect is low. Our results suggest that consumption of probiotics, prebiotics or synbiotics may be a potential adjuvant treatment for improving metabolic outcomes.

REGISTRATION

PROSPERO ID CRD42017080071. Graphical abstract.

Probiotics supplementation and insulin resistance: a systematic review

BACKGROUND

Research on intestinal microbiota has grown considerably, as well as the interest on probiotics' supplementation effects on metabolism. Considering high prevalence rates of metabolic diseases linked by insulin resistance, we performed a systematic review of existing literature which addressed the role of probiotics in modulating insulin sensitivity in animals and humans.

METHODS

This systematic review was based on PRISMA guidelines. Searches for original articles published in English from 1990 to January 2020 were made in the electronic database of PubMed from the National Library of Medicine, using Medical Subject Headings to identify longitudinal studies conducted in animals and humans which reported effects of probiotics in a variety of insulin resistance parameters.

RESULTS

Overall, results from 27 probiotic interventions (Lactobacillus, Bifidobacterium, Clostridium and Akkermansia) indicated significant beneficial changes in insulin resistance measures in animal studies. Additionally, they improved lipid profile, inflammatory and oxidative markers, short-chain fatty acids production and microbiota composition. In seven clinical trials, samples and designs were heterogeneous. Five showed benefits in insulin resistance parameters and in two others no effect was detected.

CONCLUSION

Available data regarding the effects of certain probiotics do not guarantee sustained amelioration of insulin resistance in humans. Consistent beneficial results for intestinal barrier function, immune system and metabolism were reported in animals may encourage long-term randomized clinical trials in people with obesity and cardiometabolic risk. Whether supplementation with probiotics in combination with medications and/or prebiotics, associated with a healthy lifestyle, will prove useful to attenuate insulin resistance requires further investigation.

Intervention with kimchi microbial community ameliorates obesity by regulating gut microbiota

The objective of this study was to evaluate anti-obesity effects of kimchi microbial community (KMC) on obesity and gut microbiota using a high fat diet-induced mouse model compared to effects of a single strain. Administration of KMC decreased body weight, adipose tissue, and liver weight gains. Relative content of Muribaculaceae in the gut of the KMC-treated group was higher than that in the high-fat diet (HFD) group whereas relative contents of Akkermansiaceae, Coriobacteriaceae, and Erysipelotrichaceae were lower in KMC-treated group. Metabolic profile of blood was found to change differently according to the administration of KMC and a single strain of Lactobacillus plantarum. Serum metabolites significantly increased in the HFD group but decreased in the KMC-treated group included arachidic acid, stearic acid, fumaric acid, and glucose, suggesting that the administration of KMC could influence energy metabolism. The main genus in KMC was not detected in guts of mice in KMC-treated group. Since the use of KMC has advantages in terms of safety, it has potential to improve gut microbial community for obese people.

Anti-Inflammatory Effect of a Peptide Derived from the Synbiotics, Fermented Cudrania tricuspidata with Lactobacillus gasseri, on Inflammatory Bowel Disease

The objective of this study was to evaluate the effects of peptides derived from synbiotics on improving inflammatory bowel disease (IBD). Five-week-old male C57BL/6 mice were administered with dextran sulfate sodium (DSS) via drinking water for seven days to induce IBD (IBD group). The mice in the IBD group were orally administered with PBS (IBD-PBS-positive control), Lactobacillus gasseri 505 (IBD-Pro), fermented powder of CT extract with L. gasseri 505 (IBD-Syn), β-casein: LSQSKVLPVPQKAVPYPQRDMP (IBD-Pep 1), or α _s2-casein: VYQHQKAMKPWIQPKTKVIPYVRYL (IBD-Pep 2) (both peptides are present in the synbiotics) for four more days while inducing IBD. To confirm IBD induction, the weights of the animals and the disease activity index (DAI) scores were evaluated once every two days. Following treatment of probiotics, synbiotics, or peptides for 11 days, the mice were sacrificed. The length of the small and large intestines was measured. The expression of the proinflammatory cytokines IL-1β, IL-6, TNF-α, and COX-2 in the large intestine was measured. Large intestine tissue was fixed in 10% formalin and stained with hematoxylin and eosin for histopathological analysis. The body weights decreased and DAI scores increased in the IBD group, but the DAI scores were lower in the IBD-Pep 2 group than those in the IBD group treated with PBS, Pro, Syn, or Pep 1. The lengths of the small and large intestines were shorter in the IBD group than in the group without IBD, and the expression levels of the proinflammatory cytokines were lower (p < 0.05) in the IBD-Pep 2 group than those in the IBD-PBS-positive control group. In addition, histopathological analysis showed that IBD was ameliorated in the Pep 2-treated group. These results indicate that Pep 2 derived from α _s2-casein was effective in alleviating IBD-associated inflammation. Thus, we showed that these peptides can alleviate inflammation in IBD.

Impact of Leuconostoc SD23 intake in obese pregnant rats: benefits for maternal metabolism

Maternal obesity (MO) during pregnancy and lactation leads to maternal and offspring metabolic dysfunction. Recent research has suggested that probiotics might be a novel approach to counteract these unwanted MO effects. The aim of this research was to analyze the impact of Leuconostoc SD23, a probiotic isolated from aguamiel (traditional Mexican drink), on MO metabolism in rats at the end of lactation (21 days). From weaning through lactation, control female Wistar rats (C) ate chow (5% fat) or high-energy obesogenic diet (MO; 25% fat). Half the C and MO mothers received a daily dose (1 × 1010 CFU/ml) of probiotic orally, control with probiotic (CP) and MO with probiotic (MOP), 1 month before mating and through pregnancy and lactation. Histological analyses of the liver, white adipose tissue and small intestine, body composition, glucose, insulin, triglycerides, and leptin were determined in mothers at the end of lactation. Maternal weight during pregnancy was greater in MO than C mothers, but similar at the end of lactation. Probiotic intervention had no effect on maternal weight. However, at the end of lactation, percentage of body fat was higher in MO than C, CP, and MOP. Serum glucose, homeostasis model assessment of insulin resistance, and triglycerides were higher in MO versus C, CP, and MOP. MO small intestine villus height was higher versus MOP, C, and CP. Leuconostoc SD23 did not present adverse effects in C. Conclusions: maternal administration of Leuconostoc SD23 has beneficial effects on maternal metabolism, which holds possibilities for preventing adverse offspring metabolic programming.

Microbial Medicine: Prebiotic and Probiotic Functional Foods to Target Obesity and Metabolic Syndrome

Obesity has become a global epidemic and a public health crisis in the Western World, experiencing a threefold increase in prevalence since 1975. High-caloric diets and sedentary lifestyles have been identified as significant contributors to this widespread issue, although the role of genetic, social, and environmental factors in obesity's pathogenesis remain incompletely understood. In recent years, much attention has been drawn to the contribution of the gut microbiota in the development of obesity. Indeed, research has shown that in contrast to their healthier counterparts the microbiomes of obese individuals are structurally and functionally distinct, strongly suggesting microbiome as a potential target for obesity therapeutics. In particular, pre and probiotics have emerged as effective and integrative means of modulating the microbiome, in order to reverse the microbial dysbiosis associated with an obese phenotype. The following review brings forth animal and human research supporting the myriad of mechanisms by which the microbiome affects obesity, as well as the strengths and limitations of probiotic or prebiotic supplementation for the prevention and treatment of obesity. Finally, we set forth a roadmap for the comprehensive development of functional food solutions in combatting obesity, to capitalize on the potential of pre/probiotic therapies in optimizing host health.

Probiotics, prebiotics, and synbiotics supplementation in prediabetes: protocol for a systematic review and meta-analysis

BACKGROUND

The prevalence of prediabetes and diabetes is increasing rapidly, and 5% to 10% of prediabetic patients will develop diabetes every year. Diabetes causes major health problems as well as a large economic burden. Human studies have demonstrated the beneficial effects of probiotics, prebiotics, and synbiotics supplementation in prediabetes. However, there are no systematic reviews that explore the therapeutic efficacy of probiotics, prebiotics, and synbiotics supplementation in patients with prediabetes. Therefore, we aim to synthesize the existing evidence evaluating the effectiveness and safety of probiotics, prebiotics, and synbiotics supplementation in prediabetic patients.

METHODS

We will search PubMed, EMBASE, Cochrane Library, Web of Science, the Clinical Trials.gov website, China National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang Data Knowledge Service Platform from inception to August 2020. Additionally, the search will be conducted in multiple languages. Search terms are keywords and medical subject headings related to prediabetes, probiotics, prebiotics, and synbiotics. The primary outcomes are differences in glycated hemoglobin and fasting blood glucose. The secondary outcomes are differences in fasting insulin, homeostasis model assessment of insulin resistance, quantitative insulin sensitivity check index, and adverse events. The meta-analysis will be performed using the Revman5.3.0 software provided by the Cochrane Collaboration.

RESULTS

Our study will systematically evaluate the effectiveness and safety of probiotics, prebiotics, and synbiotics supplementation in prediabetes.

CONCLUSION

The findings of this study will provide the best available evidence for probiotics, prebiotics, and synbiotics in the treatment of prediabetes, and provide a strong basis for clinical treatment.

A Fermented Food Product Containing Lactic Acid Bacteria Protects ZDF Rats from the Development of Type 2 Diabetes

Type 2 diabetes (T2D) is a complex metabolic disease, which involves a maintained hyperglycemia due to the development of an insulin resistance process. Among multiple risk factors, host intestinal microbiota has received increasing attention in T2D etiology and progression. In the present study, we have explored the effect of long-term supplementation with a non-dairy fermented food product (FFP) in Zucker Diabetic and Fatty (ZDF) rats T2D model. The supplementation with FFP induced an improvement in glucose homeostasis according to the results obtained from fasting blood glucose levels, glucose tolerance test, and pancreatic function. Importantly, a significantly reduced intestinal glucose absorption was found in the FFP-treated rats. Supplemented animals also showed a greater survival suggesting a better health status as a result of the FFP intake. Some dissimilarities have been observed in the gut microbiota population between control and FFP-treated rats, and interestingly a tendency for better cardiometabolic markers values was appreciated in this group. However, no significant differences were observed in body weight, body composition, or food intake between groups. These findings suggest that FFP induced gut microbiota modifications in ZDF rats that improved glucose metabolism and protected from T2D development.

The Role of Probiotics and Prebiotics in the Prevention and Treatment of Obesity

Obesity is a global pandemic complex to treat due to its multifactorial pathogenesis-an unhealthy lifestyle, neuronal and hormonal mechanisms, and genetic and epigenetic factors are involved. Scientific evidence supports the idea that obesity and metabolic consequences are strongly related to changes in both the function and composition of gut microbiota, which exert an essential role in modulating energy metabolism. Modifications of gut microbiota composition have been associated with variations in body weight and body mass index. Lifestyle modifications remain as primary therapy for obesity and related metabolic disorders. New therapeutic strategies to treat/prevent obesity have been proposed, based on pre- and/or probiotic modulation of gut microbiota to mimic that found in healthy non-obese subjects. Based on human and animal studies, this review aimed to discuss mechanisms through which gut microbiota could act as a key modifier of obesity and related metabolic complications. Evidence from animal studies and human clinical trials suggesting potential beneficial effects of prebiotic and various probiotic strains on those physical, biochemical, and metabolic parameters related to obesity is presented. As a conclusion, a deeper knowledge about pre-/probiotic mechanisms of action, in combination with adequately powered, randomized controlled follow-up studies, will facilitate the clinical application and development of personalized healthcare strategies.

Gut Microbiota, Host Organism, and Diet Trialogue in Diabetes and Obesity

The gastrointestinal tract with its microbiota is a complex, open, and integrated ecosystem with a high environmental exposure. It is widely accepted that the healthy gut microbiotais essential for host homeostasis and immunostasis, harboring an enormous number and variety of microorganisms and genes tailored by hundreds of exogenous and intrinsic host factors. The occurrence of dysbiosis may contribute to host vulnerability and progression to a large spectrum of infectious and non-communicable diseases, including diabetes and obesity, two metabolic disorders that are showing an endemic trend nowadays. There is an urgent need to develop efficient strategies to prevent and treat metabolic disorders such as diabetes and obesity which are often associated with serious complications. In this paper, we give an overview on the implications of gut microbiota in diabesity, with a focus on the triangle gut microbiota—diet-host metabolism and on the way to manipulate the gut microbial ecosystem toward achieving novel diagnosis and predictive biomarkers with the final goal of reestablishing the healthy metabolic condition. The current research data regarding the precision/personalized nutrition suggest that dietary interventions, including administration of pre-, pro-, and syn-biotics, as well as antibiotic treatment should be individually tailored to prevent chronic diseases based on the genetic background, food and beverage consumption, nutrient intake, microbiome, metabolome, and other omic profiles.

Using probiotics for type 2 diabetes mellitus intervention: Advances, questions, and potential

Type 2 diabetes mellitus (T2DM) has become one of the most prevalent diseases on earth and several treatments have been developed. However, the current intervention approaches have not been as effective as expected. One promising supplementary strategy is the use of probiotics through direct or indirect approaches. Probiotics are microbial food cultures conferring health-promoting properties. In this review, we summarized the current theories and mechanisms of T2DM intervention using probiotics and hypothesize that probiotics intervene T2DM during its onsetting, developing, and complicating. For the first time, we comprehensively analyzed T2DM intervention in animal models using both wide-type probiotics in different forms and using recombinant probiotics. Then, probiotic intervention in T2DM patients was reviewed and the main results were compared with that obtained from animal studies. Finally yet importantly, remaining questions that are important such as in which form and in which state, as well as the future potential of probiotic intervention in T2DM were discussed from a perspective of food microbiologists. In conclusion, probiotic intervention in T2DM is promising but there are still many important issues unsolved yet. Critical review of the advances, questions, and potential of probiotic intervention in T2DM promotes the development of this approach for further application in humans.

Effects of Prebiotic and Synbiotic Supplementation on Glycaemia and Lipid Profile in Type 2 Diabetes: A Meta-Analysis of Randomized Controlled Trials

Purpose: Diabetes Mellitus (T2DM) as a chronic disease, is on rise in parallel with other non-communicable diseases. Several studies have shown that probiotics and prebiotics might exert beneficial effects in chronic diseases including diabetes. Because of controversial results from different trials, the present study aims to assess the effects of prebiotic/synbiotic consumption on metabolic parameters in patients with type2 diabetes. Methods: A systematic literature search was performed on randomized controlled trial published in PubMed/Medline, SciVerse Scopus, Google scholar, SID and Magiran up to March 2018. Of a total number of 255 studies found in initial literature search, ten randomized controlled trials were included in the meta-analysis. The pooled mean net change were calculated in fasting blood-glucose [FBG], Hemoglobin A1c [HbA1c] and lipid markers (total cholesterol [TC], triglyceride [TG], low-density lipoprotein cholesterol [LDL-C], high density lipoprotein cholesterol [HDL-C]). The meta-analyses was conducted using Revman Software (v5.3). Results: The pooled estimate indicated a significant difference for the mean change in FBG, HbA1c and HDL in treatment group in comparison with control group. Subgroup analysis by intervention showed a significant difference in TG, LDL and HDL (synbiotic group) and in TG, TC, FBG, HDL and HbA1c (prebiotic group) compared with placebo. In another subgroup analysis, high quality studies showed significant reductions in TG, TC, FBG and HbA1c in intervention group compared with placebo group. Conclusion: In summary, diets supplemented with either prebiotics or synbiotics can result in improvements in lipid metabolism and glucose homeostasis in type 2 diabetic patients.

Lactobacillus plantarum bacteriocin is associated with intestinal and systemic improvements in diet-induced obese mice and maintains epithelial barrier integrity in vitro

We investigated the Lactobacillus plantarum bacteriocin plantaricin EF (PlnEF) system for its contributions to L. plantarum mediated benefits in a mouse model of diet-induced obesity. C57BL/6J mice on a high-fat diet (HFD) were administered a rifampicin resistant mutant of L. plantarum NCMIB8826 (NICMB8826-R) or an isogenic ΔplnEFI mutant strain, LM0419, every 48 h for nine weeks. Mice fed wild-type L. plantarum, but not LM0419, reduced their consumption of the HFD starting three weeks into the study and exhibited an overall 10% reduction in weight gain. The responses were independent of glucose homeostasis, as both NCMIB8826-R and LM0419 fed mice had improved oral glucose tolerance compared to sham controls. Although bacteriocins have antibacterial properties, the ileal, cecal, and fecal microbiota and cecocolic metabolomes were unchanged between mice fed either wild-type L. plantarum or the ΔplnEFI mutant. Instead, only mice fed NCMIB8826-R showed an increased production of ZO-1 in ileal tissues. To verify a potential role for the plantaricin EF system in supporting intestinal epithelial function, synthesized PlnEF peptides were applied to Caco-2 cell monolayers challenged with TNF-α and IFN-γ. The combination of PlnE and PlnF were required to prevent sustained cytokine-induced losses to Caco-2 cell para- and transcellular permeability and elevated IL-8 levels. In conclusion, this study shows that probiotic L. plantarum ameliorates the effects of obesogenic diets through a mechanism that involves the plantaricin EF system and likely includes L. plantarum - induced fortification of the intestinal epithelium.

Optimizing Medium Components for the Maximum Growth of Lactobacillus plantarum JNU 2116 Using Response Surface Methodology

This study was undertaken to find the optimum soy-peptone, glucose, yeast extract, and magnesium sulfate amounts for the maximum growth of Lactobacillus plantarum JNU 2116 and to assess the effects of these medium factors through the use of response surface methodology. A central composite design was used as the experimental design for the allocation of treatment combinations. In the analysis of the experiment, due to a significant lack of fit of the second-order polynomial regression model that was used at first, cubic terms were added to the model, and then two-way interaction terms were deleted from the model since they were found to be all statistically insignificant. A relative comparison among the four factors showed that the growth of L. plantarum JNU 2116 was affected strongly by yeast extract, moderately by glucose and peptone, and slightly by magnesium sulfate. The estimated optimum amounts of the medium factors for the growth of L. plantarum JNU 2116 are as follows: soy-peptone 0.213%, glucose 1.232%, yeast extract 1.97%, and magnesium sulfate 0.08%. These results may contribute to the production of L. plantarum L67 as a starter culture that may have potential application in yogurt and fermented meat products.

Chitin Oligosaccharide Modulates Gut Microbiota and Attenuates High-Fat-Diet-Induced Metabolic Syndrome in Mice

Gut microbiota has been proved to be an indispensable link between nutrient excess and metabolic syndrome, and chitin oligosaccharide (NACOS) has displayed therapeutic effects on multiple diseases such as cancer and gastritis. In this study, we aim to confirm whether NACOS can ameliorate high-fat diet (HFD)-induced metabolic syndrome by rebuilding the structure of the gut microbiota community. Male C57BL/6J mice fed with HFD were treated with NACOS (1 mg/mL) in drinking water for five months. The results indicate that NACOS improved glucose metabolic disorder in HFD-fed mice and suppressed mRNA expression of the protein regulators related to lipogenesis, gluconeogenesis, adipocyte differentiation, and inflammation in adipose tissues. Additionally, NACOS inhibited the destruction of the gut barrier in HFD-treated mice. Furthermore, 16S ribosome RNA sequencing of fecal samples demonstrates that NACOS promoted the growth of beneficial intestinal bacteria remarkably and decreased the abundance of inflammogenic taxa. In summary, NACOS partly rebuilt the microbial community and improved the metabolic syndrome of HFD-fed mice. These data confirm the preventive effects of NACOS on nutrient excess-related metabolic diseases.

Effect of atorvastatin on the gut microbiota of high fat diet-induced hypercholesterolemic rats

The aim of the present study was to investigate alterations in gut microbiota associated with hypercholesterolemia and treatment with atorvastatin, a commonly prescribed cholesterol-lowering drug. In this study, seven experimental groups of rats were developed based on diets [high-fat diet (HFD) and normal chow diet (NCD)] and various doses of atorvastatin in HFD and NCD groups. 16S rRNA amplicon sequencing was used to analyze the gut microbiota. Atorvastatin significantly reduced the cholesterol level in treated rats. Bacterial diversity was decreased in the drug-treated NCD group compared to the NCD control, but atorvastatin-treated HFD groups showed a relative increase in biodiversity compared to HFD control group. Atorvastatin promoted the relative abundance of Proteobacteria and reduced the abundance of Firmicutes in drug-treated HFD groups. Among the dominant taxa in the drug-treated HFD groups, Oscillospira, Parabacteroides, Ruminococcus, unclassified CF231, YRC22 (Paraprevotellaceae), and SMB53 (Clostridiaceae) showed reversion in population distribution toward NCD group relative to HFD group. Drug-treated HFD and NCD groups both showed an increased relative abundance of Helicobacter. Overall, bacterial community composition was altered, and diversity of gut microbiota increased with atorvastatin treatment in HFD group. Reversion in relative abundance of specific dominant taxa was observed with drug treatment to HFD rats.

Probiotic strains and mechanistic insights for the treatment of type 2 diabetes

INTRODUCTION

The intestinal microbial composition appears to differ between healthy controls and individuals with Type 2 diabetes (T2D). This observation has led to the hypothesis that perturbations of the intestinal microbiota may contribute to the development of T2D. Manipulations of the intestinal microbiota may therefore provide a novel approach in the prevention and treatment of T2D. Indeed, fecal transplants have shown promising results in both animal models for obesity and T2D and in human clinical trials. To avoid possible complications associated with fecal transplants, probiotics are considered as a viable alternative therapy. An important, however often underappreciated, characteristic of probiotics is that individual strains may have different, even opposing, effects on the host. This strain specificity exists also within the same species. A comprehensive understanding of the underlying mechanisms at the strain level is therefore crucial for the selection of suitable probiotic strains.

PURPOSE

The aim of this review is to discuss the mechanisms employed by specific probiotic strains of the Lactobacillus and the Bifidobacterium genuses, which showed efficacy in the treatment of obesity and T2D. Some probiotic strains employ recurring beneficial effects, including the production of anti-microbial lactic acid, while other strains display highly unique features, such as hydrolysis of tannins.

CONCLUSION

A major obstacle in the evaluation of probiotic strains lays in the great number of strains, differences in detection methodology and measured outcome parameters. The understanding of further research should be directed towards the development of standardized evaluation methods to facilitate the comparison of different studies.

Comparative evaluation of probiotics effects on plasma glucose, lipid, and insulin levels in streptozotocin-induced diabetic rats

BACKGROUND

Diabetes is a chronic disorder caused by the relative decrease in insulin production from the pancreas, tissue resistance to insulin, or both. Daily consumption of probiotics, particularly Lactobacilli, has been proposed as a new strategy for prevention or control of diabetes.

METHODS

In the current study, the effects of various probiotics including Lactobacillus reuteri (L reuteri), Lactobacillus crispatus (L crispatus), and Bacillus subtilis on the levels of blood glucose, lipid, and insulin as well as haemoglobin A_1c (HbA_1c ) were investigated in rat models of streptozotocin (STZ)-induced diabetes and compared with metformin. In addition, GLUT-4 and PPAR-γ transcript levels have been analysed in adipose tissues.

RESULTS

A significant decrease in plasma glucose and HbA_1c levels and a dramatic increase in insulin levels have been detected after consumption of probiotics. Furthermore, lipid profiles have been improved. The expression of Glut-4 and Ppar-γ genes in adipose tissues also increased after treatment period.

CONCLUSION

The results of this experiment showed that daily consumption of probiotics can be effective in control of STZ-induced diabetes and its complications.

Gut microbiota and probiotics: Focus on diabetes mellitus

The characterization of gut microbiota has become an important area of research in several clinical conditions, including type 2 diabetes (T2DM). Changes in the composition and/or metabolic activity of the gut microbiota can contribute to human health. Thus, this review discusses the effects of probiotics and gut microbiota on metabolic control in these individuals. Relevant studies were obtained from electronic databases such as PubMed/Medline and ISI Web of Science. The main probiotics used in these studies belonged to the genera Lactobacillus and Bifidobacterium. The authors found seven randomized placebo-controlled clinical trials and 13 experimental studies directly related to the effect of probiotics on metabolic control in the context of T2DM. The hypothesis that gut microbiota plays a role in the development of diabetes indicates an important beginning, and the potential of probiotics to prevent and reduce the severity of T2DM is better observed in animal studies. In clinical trials, the use of probiotics in glycemic control presented conflicting results, and only few studies have attempted to evaluate factors that justify metabolic changes, such as markers of oxidative stress, inflammation, and incretins. Thus, further research is needed to assess the effects of probiotics in the metabolism of diabetic individuals, as well as the main mechanisms involved in this complex relationship.

Personalized microbiome-based approaches to metabolic syndrome management and prevention

Personalized or precision medicine is a novel clinical approach targeted to the individual patient and based on integration of clinical, genetic, and environmental factors that define a patient uniquely from other individuals featuring similar clinical symptoms. Such a personalized medicine approach is increasingly applied for diagnosis, clinical stratification, and treatment of metabolic syndrome (MetS)-associated risks and diseases, including obesity, type 2 diabetes, non-alcoholic fatty liver disease, and their complications. One emerging factor that governs MetS manifestations is the microbiome, the composition, function, growth dynamics, associated metabolite profile and diverse effects of which on host immune and metabolic systems can all significantly affect metabolic homeostasis. Interindividual differences in microbiome composition and function, as well as personal variations in microbial-derived products, pave the way towards microbiome-based personalized medicine in treating MetS-related diseases.

Potential of Lactobacillus plantarum CCFM639 in Protecting against Aluminum Toxicity Mediated by Intestinal Barrier Function and Oxidative Stress

Aluminum (Al) is a ubiquitous metal that can seriously harm the health of animals and humans. In our previous study, we demonstrated that Lactobacillus plantarum CCFM639 can decrease Al burden in the tissues of mice by inhibiting intestinal Al absorption. The main aim of the present research was to investigate whether the protection by the strain is also associated with enhancement of the intestinal barrier, alleviation of oxidative stress and modulation of the inflammatory response. In an in vitro cell model, two protection modes (intervention and therapy) were examined and the results indicated that L. plantarum CCFM639 alleviated Al-induced cytotoxicity. In a mouse model, L. plantarum CCFM639 treatment was found to significantly alleviate oxidative stress in the intestinal tract, regulate the function of the intestinal mucosal immune system, restore the integrity of tight junction proteins and maintain intestinal permeability. These results suggest that in addition to Al sequestration, L. plantarum CCFM639 can also inhibit Al absorption by protecting the intestinal barrier, alleviating Al-induced oxidative stress and inflammatory response. Therefore, L. plantarum CCFM639 has the potential to be a dietary supplement ingredient that provides protection against Al-induced gut injury.

Administration of Lactobacillus casei and Bifidobacterium bifidum Ameliorated Hyperglycemia, Dyslipidemia, and Oxidative Stress in Diabetic Rats

BACKGROUND

The present work was planned to evaluate the antihyperglycemic, lipid-lowering, and antioxidant effect of Lactobacillus casei and Bifidobacterium bifidum in streptozotocin (STZ)-induced diabetic rats.

METHODS

Single daily dose of 1 × 10(7) cfu/ml of L. casei and B. bifidum alone and in combination of both was given to Wistar rats orally by gavaging for 28 days. Glucose tolerance test, fasting blood glucose (FBG), lipid profile, and glycosylated hemoglobin (HbA1c) were measured from blood. Glycogen from thigh muscles and liver and oxidative stress parameters from pancreas were analyzed.

RESULTS

Administration of L. casei and B. bifidum alone and in combination of both to diabetic rats decreased serum FBG (60.47%, 55.89%, and 56.49%, respectively), HbA1c (28.11%, 28.61%, and 28.28%), total cholesterol (171.69%, 136.47%, and 173.58%), triglycerides (9.935%, 8.58%, and 7.91%), low-density lipoproteins (53.27%, 53.35%, and 52.91%) and very low-density lipoproteins (10%, 8.58%, and 11.15%, respectively) and increased high-density lipoproteins (13.73%, 15.47%, and 15.47%), and insulin (19.50%, 25.80%, and 29.47%, respectively). The treatment also resulted in increase in muscle (171.69%, 136.47%, and 173.58%) and liver (25.82%, 6.63%, and 4.02%) glycogen level. The antioxidant indexes in pancreas of diabetic rats returned to normal level with reduction in lipid peroxidation (30.89%, 46.46%, and 65.36%) and elevation in reduced glutathione (104.5%, 161.34%, and 179.04%), superoxide dismutase (38.65%, 44.32%, and 53.35%), catalase (13.08%, 27%, and 31.52%), glutathione peroxidase (55.56%, 72.23%, and 97.23%), glutathione reductase (49.27%, 88.40%, and 110.86%), and glutathione-S-transferase (140%, 220%, and 246.6%, respectively) on treatment with L. casei, B. bifidum, and combination treatment.

CONCLUSIONS

Administration of L. casei and B. bifidum alone and in combination of both ameliorated hyperglycemia, dyslipidemia, and oxidative stress in STZ-induced diabetic Wistar rats.

Probiotics for the management of type 2 diabetes mellitus: A systematic review and meta-analysis

AIMS

To systematically review evidence of probiotic interventions against type 2 diabetes mellitus (T2DM) and analyse the effects of probiotics on glycaemic control among T2DM patients.

METHODS

Electronic search using five electronic databases was performed until October 2015. Relevant studies were identified, extracted and assessed for risk of bias. The primary outcomes of this review were glycated haemoglobin (HbA1c) and fasting blood glucose (FBG). Fasting plasma insulin, homeostasis model assessment-insulin resistance, C-reactive protein, interleukin-6 and malondialdehyde, were identified as the secondary outcomes. Mean differences (MD) between probiotics and control groups for all outcomes were pooled using either Fixed- or Random-Effect Model. Statistical heterogeneity was assessed using I(2) and Chi(2) tests.

RESULTS

Six randomised controlled trials (RCTs) were included in the systematic review, whereas only five were included in meta-analysis. Most RCTs were presented with low or unclear risk of bias. When compared to placebo, FBG was significantly lower with probiotic consumption (MD=-0.98mmol/L; 95% CI: -1.17, 0.78, p<0.00001), with moderate but insignificant heterogeneity noted. Insignificant changes between the groups were also noted for HbA1c and other secondary outcomes.

CONCLUSIONS

A moderate hypoglycaemic effect of probiotics, with a significantly lower FBG was noted. Findings on HbA1c, anti-inflammatory and anti-oxidative effects of probiotics in the clinical setting, however, remain inconsistent. The findings imply the need for well-designed clinical studies to further assess the potential beneficial effects of probiotics in management of T2DM.

Impact of gut microbiota on diabetes mellitus

Various functions of the gut are regulated by sophisticated interactions among its functional elements, including the gut microbiota. These microorganisms play a crucial role in gastrointestinal mucosa permeability. They control the fermentation and absorption of dietary polysaccharides to produce short-chain fatty acids, which may explain their importance in the regulation of fat accumulation and the subsequent development of obesity-related diseases, suggesting that they are a crucial mediator of obesity and its consequences. In addition, gut bacteria play a crucial role in the host immune system, modulation of inflammatory processes, extraction of energy from the host diet and alterations of human gene expression. Dietary modulation of the human colonic microbiota has been shown to confer a number of health benefits to the host. Simple therapeutic strategies targeted at attenuating the progression of chronic low-grade inflammation and insulin resistance are urgently required to prevent or slow the development of diabetes in susceptible individuals. The main objective of this review is to address the pathogenic association between gut microbiota and diabetes, and to explore any novel related therapeutic targets. New insights into the role of the gut microbiota in diabetes could lead to the development of integrated strategies using probiotics to prevent and treat these metabolic disorders.

Effect of short-term probiotic Enterococcus faecium SF68 dietary supplementation in overweight and obese cats without comorbidities

Obesity in cats is associated with metabolic abnormalities and increased susceptibility to diseases such as diabetes mellitus. Studies in mouse models and human beings have shown that probiotics can reduce food intake, promote weight loss and improve metabolic profile. Studies assessing the effects of probiotics on these same parameters are absent in cats. Therefore, the aim of this study was to determine if probiotic Enterococcus faecium strain SF68 dietary supplementation reduces food intake, promotes weight loss and improves metabolic profile in overweight and obese cats without comorbidities. Twenty overweight and obese specific pathogen-free cats without comorbidities were acclimatised to a dry diet for four weeks. After exclusion of four cats for unrelated reasons, eight cats received a daily oral probiotic for eight weeks and eight control cats received no probiotic. All cats were fed ad libitum with food intake measured daily and bodyweight weekly. Blood was collected at three time points: after four weeks of acclimatisation to the diet, after eight weeks of intervention and after six weeks of washout for measurement of glucose, triglyceride, cholesterol, fructosamine, insulin, leptin, total adiponectin and deuterium oxide for body composition. There were no differences in food intake, metabolic parameters and body composition between the probiotic and control groups after eight weeks of intervention and six weeks of washout (P≥0.050). Short-term use of E faecium SF68 dietary supplementation had no significant effect on food intake, bodyweight, body composition or metabolic parameters in overweight and obese specific pathogen-free cats without comorbidities.