Beneficial effects of probiotic cholesterol-lowering strain of Enterococcus faecium WEFA23 from infants on diet-induced metabolic syndrome in rats

Anti-Diabetic Potentials of Lactobacillus Strains by Modulating Gut Microbiota Structure and β-Cells Regeneration in the Pancreatic Islets of Alloxan-Induced Diabetic Rats

Diabetes mellitus, a most common endocrine disorder of glucose metabolism, has become a global epidemic and poses a serious public health threat with an increased socio-economic burden. Escalating incidence of diabetes is correlated with changes in lifestyle and food habits that cause gut microbiome dysbiosis and β-cells damage, which can be addressed with dietary interventions containing probiotics. Hence, the search for probiotics of human origin with anti-diabetic, anti-AGE, and anti-ACE potentials has gained renewed interest for the effective management of diabetes and its associated complications. The present study used an alloxan (AXN)-induced diabetic rat model to investigate the effects of potential probiotic Lacticaseibacillus casei MKU1, Lactiplantibacillus pentosus MKU3, and Lactiplantibacillus plantarum MKU7 administration individually on physiochemical parameters related to diabetic pathogenesis. Experimental animals were randomly allotted into six groups viz. NCG (control), DCG (AXN), DGM (metformin), DGP1 (MKU1), DGP2 (MKU3), and DGP3 (MKU7), and biochemical data like serum glucose, insulin, AngII, ACE, HbA1c, and TNF-α levels were measured until 90 days. Our results suggest that oral administration with MKU1, MKU3, or MKU7 significantly improved serum insulin levels, glycemic control, glucose tolerance, and body weight. Additionally, β-cell mass was increased by preserving islet integrity in Lactobacillus-treated diabetic rats, whereas TNF-α (~40%), AngII (~30%), and ACE levels (~50%) were strongly inhibited and enhanced sIgA production (5.8 folds) abundantly. Furthermore, Lactobacillus administration positively influenced the gut microbiome with a significant increase in the abundance of Lactobacillus species and the beneficial Bacteroides uniformis and Bacteroides fragilis, while decreased the pathogenic Proteus vulgaris and Parabacteroides distasonis. Among the probiotic treatment groups, L. pentosus MKU3 performed greatly in almost all parameters, indicating its potential use for alleviating diabetes-associated complications.

Maternal dietary inulin intake during late gestation and lactation ameliorates intestinal oxidative stress in piglets with the involvements of gut microbiota and bile acids metabolism

Maternal inulin intake has been shown to alleviate oxidative stress in piglets, but the role of bile acids (BAs) in this process remains unknown. This study aimed to investigate the roles of gut microbiota and BAs metabolism in the amelioration of intestinal oxidative stress in piglets through a maternal inulin diet. A total of 40 sows were allocated into two dietary treatments from day 85 of gestation until the end of lactation: CON (control diet) and INU (diet with 2% wheat bran replaced by inulin). An oxidative model was further established on the intestinal porcine epithelial cell-jejunum 2 cell line (IPEC-J2) to examine the effect of bacterial BAs on intestinal oxidative stress. Results showed that the maternal inulin diet promoted the average daily gain of piglets during suckling and reduced diarrhea rate during weaning (P = 0.026 and P = 0.005, respectively). Piglets from the INU group had lower serum levels of reactive oxygen species (P = 0.021), malondialdehyde (P = 0.045), along with higher serum levels of glutathione peroxidase (P = 0.027), catalase (P = 0.043), and total superoxide dismutase (P = 0.097). Compared to the CON group, maternal inulin intake increased fecal ursodeoxycholic acid (UDCA) by 10.84%, hyodeoxycholic acid (HDCA) by 250.64% (P = 0.026), and lithocholic acid (LCA) by 16.41% (P = 0.048) in piglets. Moreover, the fecal abundance of Ruminococcus and Christensenellaceae_R-7_group increased by 167.08% and 75.47% in INU piglets (P = 0.046 and P = 0.037, respectively). Furthermore, the in vitro study using IPEC-J2 cells demonstrated that UDCA, LCA, and HDCA attenuated intestinal oxidative stress by mediating kelch-1ike ECH-associated protein 1/nuclear factor E2-related factor 2 signaling. In conclusion, our results suggested that maternal dietary inulin intake during late gestation and lactation alleviates intestinal oxidative stress of piglets by regulating gut microbiota and BA metabolism.

Harnessing the Power of Donkey's Milk and Homemade Pickles: Unveiling Oxalate-Degrading Probiotics and Their Heat-Killed Cells as Antiadipogenic Agents in 3T3-L1 Adipocytes

Gut microbial dysbiosis is associated with the development of critical clinical conditions of metabolic syndrome (obesity, type II diabetes), and calcium oxalate kidney stones. The human gut microbial eubiosis with functional probiotics and their heat-killed cells of lactic acid bacteria (LAB) is considered the current therapy for metabolic syndrome (MS). In accordance with this, our study aimed to isolate oxalate-degrading, cholesterol-lowering, and anti-adipogenic bacterial strains from raw donkey's milk and homemade fermented pickles. Nine LAB strains with potential in vitro oxalate degrading, α-glucosidase inhibiting, and cholesterol-lowering activities were pre-screened from fourteen isolates. Further, the heat-killed cells of selected strains were evaluated for anti-adipogenic activity in murine 3T3-L1 adipocytes. This activity was examined by studying the lipid storage, gene, and protein expression of adipogenic and lipogenic transcription factors. Subsequently, four potential isolates demonstrated a significant reduction in lipid storage by limiting adipogenesis (reducing C/EBPα, PPARγ expression), lipid transportation (downregulating aP2 expression), and lipogenesis (reducing PLIN-1 expression). These effective isolates were characterized using 16S rRNA molecular sequencing, and were identified as closest relatives to the Enterococcus (RRLA5, RRLA1, and RRLD6) and Lactobacillus (RRLM2) genera. Further, they displayed good survivability under in vitro gastric conditions and non-haemolytic activity. Taken together, the live cells of effective isolates depicted significant in vitro oxalate degradation, and their heat-killed cells demonstrated anti-adipogenic activity through downregulating the adipogenesis and lipogenesis. Moreover, future preclinical animal model studies on the synergistic role of probiotics and their heat-killed cells in disease prevention through gut microbial modulation could provide evidence as a biotherapeutic agent.

In Vitro Evaluation of Probiotic Activities and Anti-Obesity Effects of Enterococcus faecalis EF-1 in Mice Fed a High-Fat Diet

This research sought to assess the anti-obesity potential of Enterococcus faecalis EF-1. An extensive and robust in vitro methodology confirmed EF-1's significant potential in combating obesity, probably due to its excellent gastrointestinal tract adaptability, cholesterol-lowering property, bile salt hydrolase activity, α-glucosidase inhibition, and fatty acid absorption ability. Moreover, EF-1 exhibited antimicrobial activity against several pathogenic strains, lacked hemolytic activity, and was sensitive to all antibiotics tested. To further investigate EF-1's anti-obesity properties in vivo, a high-fat diet (HFD) was used to induce obesity in C57BL/6J mice. Treatment with EF-1 (2 × 109 CFU/day) mitigated HFD-induced body weight gain, reduced adipose tissue weight, and preserved liver function. EF-1 also ameliorated obesity-associated microbiota imbalances, such as decreasing the Firmicutes/Bacteroidetes ratio and boosting the levels of bacteria (Faecalibacterium, Mucispirillum, Desulfovibrio, Bacteroides, and Lachnospiraceae_NK4A136_group), which are responsible for the generation of short-chain fatty acids (SCFAs). Concurrently, the levels of total SCFAs were elevated. Thus, following comprehensive safety and efficacy assessments in vitro and in vivo, our results demonstrate that E. faecalis EF-1 inhibits HFD-induced obesity through the regulation of gut microbiota and enhancing SCFA production. This strain appears to be a highly promising candidate for anti-obesity therapeutics or functional foods.

Comparative genomic and metabolomic analysis reveals the potential of a newly isolated Enterococcus faecium B6 involved in lipogenic effects

Evidence has indicated that Enterococcus plays a vital role in non-alcoholic fatty liver disease (NAFLD) development. However, the microbial genetic basis and metabolic potential in the disease are yet unknown. We previously isolated a bacteria Enterococcus faecium B6 (E. faecium B6) from children with NAFLD for the first time. Here, we aim to systematically investigate the potential of strain B6 in lipogenic effects. The lipogenic effects of strain B6 were explored in vitro and in vivo. The genomic and functional characterizations were investigated by whole-genome sequencing and comparative genomic analysis. Moreover, the metabolite profiles were unraveled by an untargeted metabolomic analysis. We demonstrated that strain B6 could effectively induce lipogenic effects in the liver of mice. Strain B6 contained a circular chromosome and two circular plasmids and posed various functions. Compared to the other two probiotic strains of E. faecium, strain B6 exhibited unique functions in pathways of ABC transporters, phosphotransferase system, and amino sugar and nucleotide sugar metabolism. Moreover, strain B6 produced several metabolites, mainly enriched in the protein digestion and absorption pathway. The unique potential of strain B6 in lipogenic effects was probably associated with glycolysis, fatty acid synthesis, and glutamine and choline transport. This study pioneeringly revealed the metabolic characteristics and specific detrimental traits of strain B6. The findings provided new insights into the underlying mechanisms of E. faecium in lipogenic effects, and laid essential foundations for further understanding of E. faecium-related disease.

Production of set-type probiotic and prebiotic yogurt-like products using Enterococcus faecium and Enterococcus faecalis strains in combination with pumpkin waste

This study investigated the effect of pumpkin powder (2 %, 4 %, and 6 %) and Enterococcus faecium and Enterococcus faecalis probiotics on the physicochemical, microbiological, and sensory properties of yogurt samples during 28 days of storage at 4 °C. The prebiotic effect of pumpkin powder (Cucurbita pepo) and the probiotic effect of Enterococcus faecium and E. faecalis were determined. Adding pumpkin powder to yogurt did not significantly alter the pH, acidity, fat, protein, and ash content (p > 0.05). Water holding was not changed during the storage time in the samples of probiotic yogurts, but as the pumpkin powder content increased, the water holding capacity also increased (p < 0.05). This situation did lead to a reduction in syneresis (p < 0.05). The lowest gumminess value at the end of storage was found in the D2 sample (p < 0.05), and the highest adhesiveness value was found in the D4 sample (p < 0.05). Furthermore, throughout the 28-day storage period, E. faecium and E. faecalis maintained a live cell count of ≥6 log CFU g-1 in the probiotic product. As a result of the statistical evaluation, there was a decrease in E. faecium in the D4, S2, and S4 samples, and then it increased again (p > 0.05) during the storage time. As a result of the statistical evaluation, it was determined that the smell, consistency in the spoon, consistency in the mouth, flavor, and acidity changes during the storage were not substantial (p > 0.05). In conclusion, it was found that pumpkin, a byproduct of the pumpkin seed industry, has the potential to act as a prebiotic and improve the properties of dairy products. Additionally, the study suggests that E. faecium and E. faecalis strains could be suitable for probiotic yogurts.

Pomegranate Juice Supplemented with Inulin Modulates Gut Microbiota and Promotes the Production of Microbiota-Associated Metabolites in Overweight/Obese Individuals: A Randomized, Double-Blind, Placebo-Controlled Trial

Pomegranate juice (PJ) and inulin have been reported to ameliorate diet-induced metabolic disorders by regulating gut microbiota dysbiosis. However, there was a lack of clinical evidence for the combined effects of PJ and inulin on regulating gut microbiota in individuals with metabolic disorders. A double-blind, parallel, randomized, placebo-controlled trial was conducted, and 68 overweight/obese individuals (25 ≤ BMI ≤ 35 kg/m2) were randomly assigned to receive 200 mL/d PJ, PJ supplemented with inulin, or placebo for 3 weeks. Our results showed that PJ and PJ+inulin did not significantly alter the levels of anthropometric and blood biochemical indicators after 3 weeks of treatment. However, there was an increasingly significant impact from placebo to PJ to PJ+inulin on the composition of gut microbiota. Detailed bacterial abundance analysis further showed that PJ+inulin treatment more profoundly resulted in significant changes in the abundance of gut microbiota at each taxonomic level than PJ. Moreover, PJ+inulin treatment also promoted the production of microbiota-associated short-chain fatty acids and pomegranate polyphenol metabolites, which correlated with the abundance of the bacterial genus. Our results suggested that PJ supplemented with inulin modulates gut microbiota composition and thus promotes the production of microbiota-associated metabolites that exert potential beneficial effects in overweight/obese subjects.

Hypocholesterolemic potential of Bacillus amyloliquefaciens KAVK1 modulates lipid accumulation on 3T3-L1 adipose cells and high fat diet-induced obese rat model

The significance of microorganisms occurring in foods is predominantly targeted due to their application for identifying a novel range of the bacterial spectrum. Diverse microbial species are capable of exhibiting potential pharmacological activities like antimicrobial and anticancer. Microbial strains capable of reducing obesity-related syndromes have also been reported. In the present study, the hypocholesterolemic efficacy of Bacillus amyloliquefaciens isolated from dairy products was scrutinised by in vitro (3T3-L1 adipose cells) and in vivo (high-fat diet-induced obese Wistar albino rats) methods. Potential cholesterol-lowering isolates were screened using a plate assay method and optimised by physical parameters. Molecular identification of the topmost five cholesterol-lowering isolates was acquired by amplification of the 16 S rRNA gene region. Bacillus amyloliquefaciens strain KAVK1, followed by strains KAVK2, KAVK3, KAVK4, and KAVK5 were molecularly determined. Further, cholesterol-lowering strains degraded the spectral patterns determined by the side chain of a cholesterol molecule. The anti-lipase activity was demonstrated using the porcine pancreatic lipase inhibitory method and compared with the reference compound Atorvastatin. Lyophilised strain KAVK1 revealed maximum pancreatic lipase inhibition. Strain KAVK1 attenuated lipid accumulation in 3T3-L1 adipose cell line predicted by Oil Red O staining method. Significant reduction of body weight and change in lipid profile was recognised after the supplement of KAVK1 to obese rats. Histopathological changes in organs were predominantly marked. The result of this study implies that the cholesterol-lowering B. amyloliquefaciens KAVK1 strain was used to treat hypercholesterolemia.

Applications of Strain-Specific Probiotics in the Management of Cardiovascular Diseases: A Systemic Review

Cardiovascular diseases (CVDs) are a leading cause of global mortality and novel approaches for prevention and management are needed. The human gastrointestinal tract hosts a diverse microbiota that is crucial in maintaining metabolic homeostasis. The formulation of effective probiotics, alone or in combination, has been under discussion due to their impact on cardiovascular and metabolic diseases. Probiotics have been shown to impact cardiovascular health positively. An imbalance in the presence of Firmicutes and Bacteroidetes has been linked to the progression of CVDs due to their impact on bile acid and cholesterol metabolism. The probiotics primarily help in the reduction of plasma low-density lipoprotein levels and attenuation of the proinflammatory markers. These beneficial microorganisms contribute to lowering cholesterol levels and produce essential short-chain fatty acids. The impact of lipid-regulating probiotic strains on human health is quite significant. However, only a few have been tested for potential beneficial efficacy, and ambiguity exists regarding strain dosages, interactions with confounding factors, and potential adverse effects. Hence, more comprehensive studies and randomized trials are needed to understand the mechanisms of probiotics on CVDs and to ensure human health. This review assesses the evidence and highlights the roles of strain-specific probiotics in the management of CVDs.

Gut microbiome as therapeutic target for diabesity management: opportunity for nanonutraceuticals and associated challenges

Diabesity is showing rising prevalence. Current treatment modalities include pharmacological and non-pharmacological approaches, yet associated with various drawbacks. Recently, gut microbial dysbiosis is documented as a crucial factor in the pathogenesis of diabesity. Targeting gut microbiome using modulators shows promising therapeutic strategy for diabesity management. In this line, nanonutraceuticals represent new class of gut microbial modulators. The present article explores the potential of nanonutraceuticals including nanoprobiotics, nanoprebiotics, and plant-derived nanovesicles that are fabricated on the ecofriendly food based scaffold with gut microbial modulatory potential for diabesity management. A number of compelling evidences from different studies support Bifidobacterium, Enterococcus, and Bacteroides genera and Lactobacillus plantarum and Akkermansia muciniphila species significant in diabesity management. The probable mechanisms reported for gut microbial dysbiosis-induced diabesity are mentioned. The review findings suggest gut microbiome as significant therapeutic target for diabesity management. Moreover, ecofriendly nanonutraceuticals developed using natural products including food-grade materials are efficient modulators of gut microbiome and indicate next-generation diabesity therapeutics. Clinical studies are imperative as further exploration may provide new dimensions to the future research.

Biodegradation of Cholesterol by Enterococcus faecium YY01

Cholesterol (CHOL) is one of the risk factors causing the blockage of the arterial wall, atherosclerosis, coronary heart disease, and other serious cardiovascular diseases. Here, a promising bacterial strain for biodegrading CHOL was successfully isolated from the gut of healthy individuals and identified as Enterococcus faecium YY01 with an analysis of the 16S rDNA sequence. An initial CHOL of 1.0 g/L was reduced to 0.5 g/L in 5 days, and glucose and beef extract were found to be optimal carbon and nitrogen sources for the rapid growth of YY01, respectively. To gain further insight into the mechanisms underlying CHOL biodegradation, the draft genome of YY01 was sequenced using Illumina HiSeq. Choloylglycine hydrolase, acyltransferase, and alkyl sulfatase was encoded by gene0586, gene1890, and gene2442, which play crucial roles in converting 3α, 7α, 12α-trihydroxy-5β-choranic acid to choline-CoA and then choline-CoA to bile acid. Notably, choloylglycine hydrolase was closely related to the biosynthesis of both primary and secondary bile acid. The findings of this study provide valuable insights into the metabolism pathway of CHOL biodegradation by YY01 and offer a potential avenue for the development of bacterioactive drugs against hypercholesterolemia.

Multidrug Resistance in Enterococci Isolated from Cheese and Capable of Producing Benzalkonium Chloride-Resistant Biofilms

This study aimed to investigate enterococci recovered from eight Portuguese cheeses made with raw ewe's milk, regarding antibiotic resistance, virulence genes, minimum inhibitory concentration (MIC) of benzalkonium chloride (BAC), biofilm formation capacity, and biofilm eradication (MBEC) by BAC. Antimicrobial resistance against seven antibiotics of five groups was evaluated using the disk diffusion method. The presence of the genes that encode resistance to the antibiotics penicillin (blaZ), erythromycin (ermA, ermB, and ermC), vancomycin (vanA and vanB), aminoglycoside (aac(6')-Ie-aph(2″)-Ia), and β-lactam (pbp5) and the genes that encode virulence factors, frsB, cylA, gelE, esp, and agg, were investigated via multiplex PCR. The susceptibility of planktonic cells to BAC was evaluated by the MIC and MBC values of the isolates, using the broth microdilution method. To assess the biofilm-forming ability and resistance of biofilms to BAC, biofilms were produced on stainless steel coupons, followed by exposure to BAC. The results showed a high resistance to the antibiotics vancomycin (87.5%), erythromycin (75%), tetracycline (50%), and penicillin (37.5%). Multidrug resistance was observed in 68.8% of the isolates. Genes encoding the virulence factors FrsB (frsB) and gelatinase E (gelE) were detected in all isolates. The esp and cylA genes were found in 56.3% and 37.5% of the isolates, respectively. All isolates exhibited a biofilm-forming ability, regardless of incubation time and temperature tested. However, after 72 h at 37 °C, E. faecium and E. faecalis biofilms showed significant differences (p ≤ 0.05). Although most isolates (62.5%) were susceptible to BAC (MIC ≤ 10 mg/L), biofilms of the same isolates were, generally, resistant to the higher concentration of BAC (80 mg/mL) tested. This study using Enterococcus isolates from a ready-to-eat food, such as cheese, reveals the high percentages of vancomycin resistance and multidrug resistance, associated with the presence of virulence genes, in isolates also capable of producing biofilms resistant to BAC, an important active ingredient of many disinfectants. These results emphasize the need for effective control measures to ensure the safety and quality of dairy products.

Ranuncoside's attenuation of scopolamine-induced memory impairment in mice via Nrf2 and NF-ĸB signaling

Scopolamine is a well-known pharmacological agent responsible for causing memory impairment in animals, as well as oxidative stress and neuroinflammation inducer which lead to the development of Alzheimer disease. Although a cure for Alzheimer's disease is unavailable. Ranuncoside, a metabolite obtained from a medicinal plant has demonstrated antioxidant and anti-inflammatory properties in vitro, making it a promising treatment with potential anti-Alzheimer disease properties. However, as ranuncoside has not been evaluated for its antioxidant and anti-neuroinflammatory properties in any in vivo model, our study aimed to evaluate its neurotherapeutic efficacy against scopolamine-induced memory impairment in adult male albino mice. Mice were randomly divided into four experimental groups. Mice of group I was injected with saline, group II was injected with scopolamine (1 mg/kg/day) for 3 weeks. After receiving a daily injection of scopolamine for 1 week, the mice of group III were injected with ranuncoside (10 mg/kg) every other day for 2 weeks along with scopolamine daily and group IV were injected with ranuncoside on 5th alternate days. Behavioral tests (i.e., Morris water maze and Y-maze) were performed to determine the memory-enhancing effect of ranuncoside against scopolamine's memory deleterious effect. Western blot analysis was also performed to further elucidate the anti-neuroinflammatory and antioxidant effects of ranuncoside against scopolamine-induced neuroinflammation and oxidative stress. Our results showed memory-enhancing, anti-neuroinflammatory effect, and antioxidant effects of ranuncoside against scopolamine by increasing the expression of the endogenous antioxidant system (i.e., Nrf2 and HO-1), followed by blocking neuroinflammatory markers such as NF-κB, COX-2, and TNF-α. The results also revealed that ranuncoside possesses hypoglycemic and hypolipidemic effects against scopolamine-induced hyperglycemia and hyperlipidemia in mice as well as scopolamine's hyperglycemic effect. In conclusion, our findings suggest that ranuncoside could be a potential agent for the management of Alzheimer's disease, hyperglycemia, and hyperlipidemia.

Bi-Directional Interactions between Glucose-Lowering Medications and Gut Microbiome in Patients with Type 2 Diabetes Mellitus: A Systematic Review

Background: Although common drugs for treating type 2 diabetes (T2D) are widely used, their therapeutic effects vary greatly. The interaction between the gut microbiome and glucose-lowering drugs is one of the main contributors to the variability in T2D progression and response to therapy. On the one hand, glucose-lowering drugs can alter gut microbiome components. On the other hand, specific gut microbiota can influence glycemic control as the therapeutic effects of these drugs. Therefore, this systematic review assesses the bi-directional relationships between common glucose-lowering drugs and gut microbiome profiles. Methods: A systematic search of Embase, Web of Science, PubMed, and Google Scholar databases was performed. Observational studies and randomised controlled trials (RCTs), published from inception to July 2023, comprising T2D patients and investigating bi-directional interactions between glucose-lowering drugs and gut microbiome, were included. Results: Summarised findings indicated that glucose-lowering drugs could increase metabolic-healthy promoting taxa (e.g., Bifidobacterium) and decrease harmful taxa (e.g., Bacteroides and Intestinibacter). Our findings also showed a significantly different abundance of gut microbiome taxa (e.g., Enterococcus faecium (i.e., E. faecium)) in T2D patients with poor compared to optimal glycemic control. Conclusions: This review provides evidence for glucose-lowering drug and gut microbiome interactions, highlighting the potential of gut microbiome modulators as co-adjuvants for T2D treatment.

Beneficial Effects of Indigenous Probiotics in High-Cholesterol Diet-Induced Hypercholesterolemic Rats

Hypercholesterolemia is a significant risk factor for cardiovascular disease and metabolic disorders. Probiotics are the essential constituents of the gastrointestinal microbiota that provide health-promoting effects. Cholesterol-lowering activity is a specific property of probiotics, improving the cholesterol metabolism without adverse effects. Thus, the purpose of this study was to investigate the hypocholesterolemic effect of single and mixed cholesterol-lowering probiotic strains (including Limosilactobacillus reuteri TF-7, Enterococcus faecium TF-18, and Bifidobacterium animalis TA-1) in high-cholesterol diet (HCD)-induced hypercholesterolemic rats. The results showed that the administration of single probiotics contributed to a reduction in the body weight gain, visceral organ indexes, hyperlipidemia, and hepatic steatosis and also an improvement in the gastrointestinal microbiota. Besides the effect of single cholesterol-lowering probiotics, three probiotics strains could also synergize their hypocholesterolemic effect when administered simultaneously. These findings indicate that three cholesterol-lowering probiotic strains are suitable for development as probiotic supplements to reduce the risk of diseases caused by cholesterol and exert health benefits with synergistic effect when administered simultaneously.

Exploring the Cholesterol-Modifying Abilities of Lactobacilli Cells in Digestive Models and Dairy Products

This study aimed to investigate the ability of lactic acid bacteria to remove cholesterol in simulated gastric and intestinal fluids. The findings showed that the amount of cholesterol removed was dependent on the biomass, viability, and bacterial strain. Some cholesterol binding was stable and not released during gastrointestinal transit. The presence of cholesterol affected the fatty acid profile of bacterial cells, potentially influencing their metabolism and functioning. However, adding cholesterol did not significantly impact the survival of lactic acid bacteria during gastrointestinal transit. Storage time, passage, and bacterial culture type did not show significant effects on cholesterol content in fermented dairy products. Variations in cell survival were observed among lactic acid bacteria strains in simulated gastric and intestinal fluids, depending on the environment. Higher milk protein content was found to be more protective for bacterial cells during gastrointestinal transit than fat content. Future research should aim to better understand the impact of cholesterol on lactic acid bacteria metabolism and identify potential health benefits.

Alleviation Syndrome of High-Cholesterol-Diet-Induced Hypercholesterolemia in Mice by Intervention with Lactiplantibacillus plantarum WLPL21 via Regulation of Cholesterol Metabolism and Transportation as Well as Gut Microbiota

Probiotics are prospective for the prevention and treatment of cardiovascular diseases. Until now, systematic studies on the amelioration of hypercholesterolemia have been rare in terms of (cholesterol metabolism and transportation, reshaping of gut microbiota, as well as yielding SCFAs) intervention with lactic acid bacteria (LAB). In this study, strains of Lactiplantibacillus plantarum, WLPL21, WLPL72, and ZDY04, from fermented food and two combinations (Enterococcus faecium WEFA23 with L. plantarum WLPL21 and WLPL72) were compared for their effect on hypercholesterolemia. Comprehensively, with regard to the above aspects, L. plantarum WLPL21 showed the best mitigatory effect among all groups, which was revealed by decreasing total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels, upregulated cholesterol metabolism (Cyp27a1, Cyp7b1, Cyp7a1, and Cyp8b1) levels in the liver, cholesterol transportation (Abca1, Abcg5, and Abcg8) in the ileum or liver, and downregulated Npc1l1. Moreover, it reshaped the constitution of gut microbiota; specifically, the ratio of Firmicutes to Bacteroidetes (F/B) was downregulated; the relative abundance of Allobaculum, Blautia, and Lactobacillus was upregulated by 7.48-14.82-fold; and that of Lachnoclostridium and Desulfovibrio was then downregulated by 69.95% and 60.66%, respectively. In conclusion, L. plantarum WLPL21 improved cholesterol metabolism and transportation, as well as the abundance of gut microbiota, for alleviating high-cholesterol-diet-induced hypercholesterolemia.

Comprehensive genomic analysis of hypocholesterolemic probiotic Enterococcus faecium LR13 reveals unique proteins involved in cholesterol-assimilation

Hypercholesterolemia is a major risk factor for cardiovascular diseases (CVDs). Chemotherapeutic agents for CVDs exhibit several side effects. Specific probiotics with hypocholesterolemic effects can be safe and effective alternatives to chemotherapeutics. Here, we have analyzed and compared the genome of a novel rhizospheric Enterococcus faecium LR13 cholesterol-assimilating probiotic with other probiotic/pathogenic E. faecium strains to discern genetic factors underlying probiotic efficacy and cholesterol-assimilation. Genomic analyses of E. faecium probiotic strains revealed that LR13 and WEFA23 (cholesterol-assimilating probiotics) harbored 21 unique proteins absent in non-cholesterol-assimilating probiotics. Of these, 14 proteins could directly help in cholesterol-assimilation by producing short chain fatty acids, lipid (sterol) transport and membrane stabilization, and bile salt hydrolase activity. This suggests that cholesterol-assimilation is an intrinsic, strain-specific trait exhibited by probiotics with a specific genetic constitution. Moreover, the unique proteins identified in this study can serve as biomarkers for discerning/characterizing cholesterol-assimilating probiotics as novel biotherapeutics against CVDs.

Anti-tumor effect of infant-derived Enterococcus via the inhibition of proliferation and inflammation as well as the promotion of apoptosis

Probiotic Enterococcus hirae WEHI01 and Enterococcus faecium WEFA23 from infants were previously found to effectively inhibit the development of melanoma. In this study, their immunomodulatory and antitumor mechanisms were systemically studied. In vitro assay showed that E. hirae WEHI01 and E. faecium WEFA23 achieved biphasic immune regulation, which was revealed by the activation of resting spleen lymphocytes and RAW264.7 macrophages, as well as the anti-inflammation effect when immune cells were treated with LPS. The antitumor effects of E. hirae WEHI01 and E. faecium WEFA23 in vitro and vivo were then investigated. CCK8 and the cell scratch assay showed that the conditioned media, which were co-incubated with Enterococcus and spleen lymphocytes, significantly inhibited the proliferation and migration of B16F10, HepG-2 and HT-29 cells. The results of the tumor-bearing mice model experiment showed that E. faecium WEFA23 inhibition of the growth of tumors in mice, and the anti-tumor mechanism involved three aspects, namely tumor proliferation (decreasing expressions of LDHA, VEGF, MMP2, MMP9 and HIF-1α), inhibition of the pro-inflammation state (decreasing expressions of IL-6, TGF-β and IL-17) and the promotion of apoptosis (increasing expression of Bax/Bcl-2, caspase-3 and p53). The results suggest that the two strains of Enterococcus could be promising candidates for treating melanoma with a highly inhibitory effect.

The administration of Enterococcus faecium SF68 counteracts compositional shifts in the gut microbiota of diet-induced obese mice

Microorganisms with probiotic properties are eliciting an increasing interest as coadjuvants in the prevention and treatment of obesity through modulation of the gut microbiota. In this study, a probiotic formulation based on Enterococcus faecium SF68 was administered to mice fed with a high-fat diet (HFD) to evaluate its efficacy in reducing body mass gain and in modulating the intestinal bacterial composition. Both stool and ileum samples were collected from untreated and treated mice and absolute abundances of specific taxa constituting the gut microbial consortium were evaluated. SF68 administration significantly reduced the HFD-induced weight gain. In these animals, the microbial gut composition shifted toward an enrichment in microbes positively correlated with mucus thickness, lower inflammation, lower glycemia levels, and SCFA production (i.e., Bifidobacterium, Akkermansia, and Faecalibacterium), as well as a depletion in bacterial phyla having a key role in obesity (i.e., Firmicutes, Proteobacteria). Our results demonstrate the efficacy of E. faecium SF68 in adjusting the composition of the dysbiotic microbiota of HFD-fed animals, thus ameliorating clinical conditions and exerting anti-obesity effects.

Enterococcus faecium GEFA01 alleviates hypercholesterolemia by promoting reverse cholesterol transportation via modulating the gut microbiota-SCFA axis

This study aimed to identify cholesterol-lowering commensal strains from healthy lean individuals and to evaluate the cholesterol-lowering capacity of Enterococcus faecium GEFA01 in mice fed a high-cholesterol and high-fat diet. E. faecium GEFA01 was isolated from the feces of a healthy lean individual in a selective basal salt medium supplemented with cholesterol. E. faecium GEFA01 exhibited a cholesterol removal rate (CRR) of 46.13% by coprecipitation, assimilation, and degradation of cholesterol. Moreover, E. faecium GEFA01 significantly decreased the body weight of mice and the levels of serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), hepatic TC, triglycerides (TG), and LDL-C, and increased serum high-density lipoprotein cholesterol (HDL-C) levels in mice fed a high-cholesterol diet compared with the HCD group. We also observed that E. faecium GEFA01 significantly downregulated the gene expression of HMG-CoA reductase (Hmgcr), Srebp-1c, Fxr, Shp, and Fgf 15, upregulated the gene expression of low-density lipoprotein receptor (Ldlr), Abcg5/8, Abca1, cholesterol 7 alpha-hydroxylase (Cyp7a1), and Lxr in the liver of mice in relative to the HCD group, markedly increased the relative abundance of Lactobacillus, Akkermansia, Bifidobacterium, and Roseburia, and decreased the abundance of Helicobacter in the feces. Collectively, we confirmed that E. faecium GEFA01 exhibited cholesterol-lowering effects in mice fed a high-cholesterol diet, which was achieved through assimilation, coprecipitation, and degradation of cholesterol, and through modulation of the gut microbiota short-chain fatty acid (SCFA) axis that promoted reverse cholesterol transport and bile acid excretion. Our study demonstrated that E. faecium GEFA01 may be used as a probiotic candidate to lower cholesterol levels in the future.

Characterization of Novel Exopolysaccharides from Enterococcus hirae WEHI01 and Its Immunomodulatory Activity

Exopolysaccharide (EPS) from probiotic Enterococcus hirae WEHI01 was isolated and purified by anion exchange chromatography and gel chromatography, the results of which show that the EPS consists of four fractions, namely I01-1, I01-2, I01-3, and I01-4. As the main purification components, I01-2 and I01-4 were preliminarily characterized for their structure and their immunomodulatory activity was explored. The molecular weight of I01-2 was 2.28 × 104 Da, which consists mainly of galactose, and a few other sugars including glucose, arabinose, mannose, xylose, fucose, and rhamnose, while the I01-4 was composed of galactose only and has a molecular weight of 2.59 × 104 Da. Furthermore, the results of an evaluation of immunomodulatory activity revealed that I01-2 and I01-4 could improve the viability of macrophage cells, improve phagocytosis, boost NO generation, and encourage the release of cytokines including TNF-α and IL-6 in RAW 264.7 macrophages. These results imply that I01-2 and I01-4 could improve macrophage-mediated immune responses and might be useful in the production of functional food and medications.

Lotus (Nelumbo nucifera Gaertn.) Leaf-Fermentation Supernatant Inhibits Adipogenesis in 3T3-L1 Preadipocytes and Suppresses Obesity in High-Fat Diet-Induced Obese Rats

The lotus (Nelumbo nucifera Gaertn.) leaf is a typical homologous ingredient of medicine and food with lipid-lowering and weight-loss effects. In the present study, lotus leaves were fermented by two probiotics, Enterococcus faecium WEFA23 and Enterococcus hirae WEHI01, and the anti-adipogenic effect of Enterococcus fermented lotus leaf supernatant (FLLS) was evaluated in 3T3-L1 preadipocytes with the aim of exploring whether its anti-obesity ability will be enhanced after fermentation with Enterococcus and to dig out the potential corresponding mechanism. The FLLS fermented by E. hirae WEHI01 (FLLS-WEHI01) was selected and further investigated for its ability to inhibit obesity in vivo in high-fat diet (HFD)-induced obese rats (male, 110 ± 5 g, 4 weeks old) due to its superior inhibitory effect on adipogenesis and lipid accumulation (inhibition rate of up to 56.17%) in 3T3-L1 cells (p = 0.008 for WEHI01-L, p < 0.001 for WEHI01-H). We found that the oral administration of both the low and high doses of FLLS-WEHI01 could achieve some effects, namely decreasing body weight (p < 0.001), epididymal fat mass, adipocyte cell size, LDL-C levels (p = 0.89, 0.02, respectively), liver TC levels (p < 0.001, p = 0.01, respectively), and TG levels (p = 0.2137, p = 0.0464, respectively), fasting blood glucose (p = 0.1585, p = 0.0009), and improved insulin resistance (p = 0.33, 0.01, respectively) in rats of the model group. Moreover, the administration of both high and low doses of FLLS-WEHI01 decreased the transcription levels of adipogenic transcription factors and corresponding genes such as Pparγ (p < 0.001), Cebpα (p < 0.001), Acc (p < 0.001), and Fas (p < 0.001) by at least three times. These results indicate that FLLS-WEHI01 can potentially be developed as an healthy, anti-obesity foodstuff.

The ameliorative effect of probiotics on diet-induced lipid metabolism disorders: A review

High-fat diet induces lipid metabolism disorders that has become one of the grievous public health problems and imposes a serious economic and social burden worldwide. Safety probiotics isolated from nature are regarded as a novel supplementary strategy for preventing and improving diet-induced lipid metabolism disorders and related chronic diseases. The present review summarized the latest researches of probiotics in high fat diet induced lipid metabolism disorders to provide a critical perspective on the regulatory function of probiotics for future research. Furthermore, the screening criteria and general sources of probiotics with lipid-lowering ability also outlined to enlarge microbial species resource bank instantly, which promoted the development of functional foods with lipid-lowering strains from nature. After critically reviewing the lipid-lowering potential of probiotics both in vitro and in vivo and even in clinical data of humans, we provided a perspective that probiotics activated AMPK signaling pathway to regulate fat synthesis and decomposition, as well as affected positively the gut microbiota structure, intestinal barrier function and systemic inflammatory response, then these beneficial effects are amplified along Gut-liver axis, which regulated intestinal flora metabolites such as SCFAs and BAs by HMGCR/FXR/SHP signaling pathway to improve high fat diet induced lipid metabolism disorders effectively.

Characterization of interactions of dietary cholesterol with the murine and human gut microbiome

Consumption of dietary lipids, such as cholesterol, modulates the gut microbiome with consequences for host health through the production of microbiome-derived metabolites. Despite the implications for host metabolism, a limited number of specific interactions of the gut microbiome with diet-derived lipids have been characterized. This is partially because obtaining species-level resolution of the responsible taxa can be challenging and additional approaches are needed to identify health-relevant metabolites produced from cholesterol-microbiome interactions. Here we performed bio-orthogonal labelling sort sequence spectrometry, a click chemistry based workflow, to profile cholesterol-specific host-microbe interactions. Mice were exposed to an alkyne-functionalized variant of cholesterol and 16S ribosomal RNA gene amplicon sequencing of faecal samples identified diet-derived cholesterol-interacting microbes from the genera Bacteroides, Bifidobacterium, Enterococcus and Parabacteroides. Shotgun metagenomic analysis provided species-level resolution of diet-derived cholesterol-interacting microbes with enrichment of bile acid-like and sulfotransferase-like activities. Using untargeted metabolomics, we identify that cholesterol is converted to cholesterol sulfate in a Bacteroides-specific manner via the enzyme BT_0416. Mice monocolonized with Bacteroides thetaiotaomicron lacking Bt_0416 showed altered host cholesterol and cholesterol sulfate compared with wild-type mice, identifying a previously uncharacterized microbiome-transformation of cholesterol and a mechanism for microbiome-dependent contributions to host phenotype. Moreover, identification of a cholesterol-responsive sulfotransferase in Bacteroides suggests diet-dependent mechanisms for altering microbiome-specific cholesterol metabolism. Overall, our work identifies numerous cholesterol-interacting microbes with implications for more precise microbiome-conscious regulation of host cholesterol homeostasis.

Akkermansia muciniphila Enhances Egg Quality and the Lipid Profile of Egg Yolk by Improving Lipid Metabolism

Akkermansia muciniphila (A. muciniphila) has shown potential as a probiotic for the prevention and treatment of non-alcoholic fatty liver disease in both humans and mice. However, relatively little is known about the effects of A. muciniphila on lipid metabolism, productivity, and product quality in laying hens. In this study, we explored whether A. muciniphila supplementation could improve lipid metabolism and egg quality in laying hens and sought to identify the underlying mechanism. In the first experiment, 80 Hy-Line Brown laying hens were divided into four groups, one of which was fed a normal diet (control group), while the other three groups were administered a high-energy, low-protein diet to induce fatty liver hemorrhagic syndrome (FLHS). Among the three FLHS groups, one was treated with phosphate-buffered saline, one with live A. muciniphila, and one with pasteurized A. muciniphila. In the second experiment, 140 Hy-Line Brown laying hens were divided into two groups and respectively fed a basal diet supplemented or not with A. muciniphila lyophilized powder. The results showed that, in laying hens with FLHS, treatment with either live or pasteurized A. muciniphila efficiently decreased body weight, abdominal fat deposition, and lipid content in both serum and the liver; downregulated the mRNA expression of lipid synthesis-related genes and upregulated that of lipid transport-related genes in the liver; promoted the growth of short-chain fatty acids (SCFAs)-producing microorganisms and increased the cecal SCFAs content; and improved the yolk lipid profile. Additionally, the supplementation of lyophilized powder of A. muciniphila to aged laying hens reduced abdominal fat deposition and total cholesterol (TC) levels in both serum and the liver, suppressed the mRNA expression of cholesterol synthesis-related genes in the liver, reduced TC content in the yolk, increased eggshell thickness, and reshaped the composition of the gut microbiota. Collectively, our findings demonstrated that A. muciniphila can modulate lipid metabolism, thereby, promoting laying hen health as well as egg quality and nutritive value. Live, pasteurized, and lyophilized A. muciniphila preparations all have the potential for use as additives for improving laying hen production.

Strategies for the Identification and Assessment of Bacterial Strains with Specific Probiotic Traits

Early in the 1900s, it was proposed that health could be improved and senility delayed by manipulating gut microbiota with the host-friendly bacteria found in yogurt. Later, in 1990, the medical community reconsidered this idea and today probiotics represent a developed area of research with a billion-dollar global industry. As a result, in recent decades, increased attention has been paid to the isolation and characterization of novel probiotic bacteria from fermented foods and dairy products. Most of the identified probiotic strains belong to the lactic acid bacteria group and the genus Bifidobacterium. However, current molecular-based knowledge has allowed the identification and culture of obligatory anaerobic commensal bacteria from the human gut, such as Akkermansia spp. and Faecalibacterium spp., among other human symbionts. We are aware that the identification of new strains of these species does not guarantee their probiotic effects and that each effect must be proved through in vitro and in vivo preclinical studies before clinical trials (before even considering it as a probiotic strain). In most cases, the identification and characterization of new probiotic strain candidates may lack the appropriate set of in vitro experiments allowing the next assessment steps. Here, we address some innovative strategies reported in the literature as alternatives to classical characterization: (i) identification of alternatives using whole-metagenome shotgun sequencing, metabolomics, and multi-omics analysis; and (ii) probiotic characterization based on molecular effectors and/or traits to target specific diseases (i.e., inflammatory bowel diseases, colorectal cancer, allergies, among others).

Revealing Probiotic Potential of Enterococcus Strains Isolated From Traditionally Fermented Chhurpi and Healthy Human Gut

In this study, the two lactic acid bacterial strains Enterococcus durans and Enterococcus lactis previously isolated from soft chhurpi, a traditionally fermented milk product prepared by the indigenous community of Sikkim Himalayas and healthy human gut were used. In this study, we attempted to investigate the probiotic attributes, safety, and health beneficial role, and hypercholesterolemia of Enterococcus durans and Enterococcus lactis. Both probiotic potential strains showed good hypocholesterolemic activity in vitro along with tolerance to acid pH (2 and 2.5), tolerance to three bile salts, oxbile, cholic acid, and taurocholic acid (0.5 and 1%), presence of BSH enzyme and its activity, and cell surface adherence. On assessing for safety, both LAB strains were sensitive to antibiotics and exhibited no hemolytic activity. The probiotic strains were tested in vivo in the Sprague–Dawley rats which were divided into five experimental groups: Normal Control (ND), probiotic strain Enterococcus durans HS03 (BSH-negative) and high-cholesterol diet (HCD1), probiotic strain Enterococcus lactis YY1 (BSH-positive) and high-cholesterol diet (HCD2), and a combination of both strains and high-cholesterol diet (HCD3) and Negative Control (HCD). The probiotic-treated groups HCD1, HCD2, and HCD3 showed a decrease in serum cholesterol levels up to 22.55, 6.67, and 31.06%; the TG and VLDL concentrations were 25.39, 26.3, and 33.21%; reduction in LDL-cholesterol was 33.66, 28.50, and 35.87%; and increase of HDL was 38.32, 47.9, and 41.92%. Similarly, the effects of total cholesterol and TG in the liver, kidney and liver histopathology, liver and body lipid index, and oxidative stress in rat liver were also studied. The fecal lactobacilli were more in the samples of the probiotic-treated groups and their fecal coliform and E. coli counts decreased relatively as compared to the control groups in 0, 7, 14, and 21 days. This is the first report on the probiotic potential of Enterococcus durans HS03 and Enterococcus lactis YY1 strains that gives a new insight into the cholesterol-lowering and probiotic product development with wide health attributes.

Assessment of Two Potential Probiotic Strains As Anti-Obesity Supplements Under High-Fat Feeding Conditions

Obesity is one of the chronic diseases that increase annually and cause cardiovascular disease, which is the main cause of death worldwide. So, this study aims to evaluate the role of the two potential probiotics: Lactiplantibacillus plantarum Pro1 and Lacticaseibacillus rhamnosus Pro2, isolated from the fermented milk and corn silage as anti-obesity supplements. Seventy-five male BALB/c mice were distributed to five groups (control, obesity, obesity plus L. plantarum (OLP), obesity plus L. rhamnosus (OLR) and obesity plus mixture of two strains (OM)). The body weight, lipid profile, histopathology and enzymes of liver were assessed. RT-PCR was used to determine the expression of CYP7A1, ALTG4, TNFα and ROR genes.The findings show that the obesity group recorded the significant highest value of the body weight, TC, TG, LDL, AST and ALT, while OLP group recorded the significant lowest value. Liver tissue of obesity group has necrosis and fatty changes, while the OLP group was related to the control group. The findings of RT-PCR show non-significant differences between the control group and the OLP group, with significant differences between the control group and the set groups in expression of CYP7A1, ALTG4, TNFα and ROR genes. L. plantarum Pro1 reduced the expression of inflammation genes (TNFα and ROR), and increase the expression of the lipid metabolism genes (CYP7A1, ALTG4) to reduce the inflammatory effects of obesity in the liver, and decrease the cholesterol level in serum. Therefore, L. plantarum Pro1 is useful as anti-obesity supplements and an eliminator of the relevant diseases.

WHOLE-meal ancient wheat-based diet: Effect on metabolic parameters and microbiota

BACKGROUND & AIMS

Ancient wheat varieties are considered to be healthier than modern ones, but the data are not univocal. We investigated changes in hematochemical parameters and evaluated microbiota data before and after a set period on a diet containing a whole-meal ancient wheat mix.

PATIENTS AND METHODS

29 cloistered nuns were recruited. The study comprised two consecutive 30-day periods; during the first one (T1), the nuns received wheat-based foods produced with refined "modern" flour ("Simeto"); during the second one (T2) received wheat-based foods produced with an unrefined flour mix composed of "ancient" cultivars. At entry to the study (T0) and at the end of T1 and T2 hematochemical parameters and fecal microbiota and metabolome were evaluated.

RESULTS

At the end of T2, there was a significant reduction in serum iron, ferritin, creatinine, sodium, potassium, magnesium, total cholesterol, LDL- and HDL-cholesterol and folic acid. Furthermore, increased the abundance of cultivable enterococci, lactic acid bacteria and total anaerobes. The ability of the gut microbiome to metabolize carbohydrates increased after the period of diet containing ancient grain products. Several volatile organic compounds increased after the one month on the diet enriched with ancient grain products.

CONCLUSIONS

Our data showed the beneficial effects deriving from a diet including ancient whole-meal/unrefined wheat flours.

Potential Probiotic Enterococcus faecium OV3-6 and Its Bioactive Peptide as Alternative Bio-Preservation

Probiotic Enterococcus faecium OV3-6 and its secreted active peptide were characterized and investigated. The strain survived in simulated gastric and small intestinal conditions at 88.16% and 94.33%, respectively. The safety assessment revealed that the strain was shown α-hemolysis and susceptible to most clinically relevant antibiotics, but intermediate sensitivity to erythromycin and kanamycin was found. It does not harbor any virulence genes except for the efaA_fm gene. Both of its living cells and the cell-free supernatants (CFS) of the strain significantly reduced the adhesion of E. coli and S. Typhi on Caco-2 cells. The strain can regulate the secretion of pro and inflammatory cytokines, IL-6 and IL-12 and induce the secretion of anti-inflammatory IL-10 of the Caco-2 cell. The strain can prevent the growth of Gram-positive strains belonging to the genera Bacillus, Carnobacterium, Listeria, and Staphylococcus. It also presented the entP gene that involves the production of bacteriocin named enterocin P. The antimicrobial peptide was matched 40% with 50S ribosomal proteins L29 (7.325 kDa), as revealed by LC-MS/MS. This active peptide exhibits heat stability, is stable over a wide pH range of 2−10, and maintains its activity at −20 and 4 °C for 12 weeks of storage. Altogether, E. faecium OV3-6 thus has potential for consideration as a probiotic and bio-preservative for applied use as a fermented food starter culture and in functional food or feed industries.

Lactobacillus reuteri FYNLJ109L1 Attenuating Metabolic Syndrome in Mice via Gut Microbiota Modulation and Alleviating Inflammation

Metabolic syndrome is caused by an excessive energy intake in a long-term, high-fat and/or high-sugar diet, resulting in obesity and a series of related complications, which has become a global health concern. Probiotics intervention can regulate the gut microbiota and relieve the systemic and chronic low-grade inflammation, which is an alternative to relieving metabolic syndrome. The aim of this work was to explore the alleviation of two different Lactobacillusreuteri strains on metabolic syndrome. Between the two L. reuteri strains, FYNLJ109L1 had a better improvement effect on blood glucose, blood lipid, liver tissue damage and other related indexes than NCIMB 30242. In particular, FYNLJ109L1 reduced weight gain, food intake and fat accumulation. Additionally, it can regulate the gut microbiota, increase IL-10, and reduce IL-6 and tumor necrosis factor-α (TNF-α), as well as liver injury, and further reduce insulin resistance and regulate lipid metabolism disorders. In addition, it could modulate the gut microbiota, particularly a decreased Romboutsia and Clostridium sensu stricto-1, and an increased Acetatifactor. The results indicated that FYNLJ109L1 could improve metabolic syndrome significantly via alleviating inflammation and gut microbiota modulation.

Improving the Gut Microbiota with Probiotics and Faecal Microbiota Transplantation

Probiotics are “live strains of strictly selected microorganisms which, when administered in adequate amounts, confer a health benefit on the host”. After birth, our intestine is colonized by microbes like Escherichia coli, Clostridium spp., Streptococcus spp., Lactobacillus spp., Bacteroides spp., and Bifidobacterium spp. Our intestine is an extremely complex living system that participates in the protection of host through a strong defence against external aggregations. The microbial ecosystem of the intestine includes many native species of Bacteroides and Firmicutes that permanently colonize the gastrointestinal tract. The composition of flora changes over time depending upon diet and medical emergencies which leads to the diseased condition. Probiotics exert their mode of action by altering the local environment of the gut by competing with the pathogens, bacteriocins production, H2O2 production etc. Obesity is one of the major health problems and is considered as the most prevalent form of inappropriate nutrition. Probiotics like Lactobacillus Sp., Bifidobacterium Sp., Streptococcus Sp. are successfully used in the treatment of obesity proved in clinical trials. Faecal microbiota transplant (FMT), also known as a stool transplant, is the process of transplantation of Faecal bacteria from a healthy donor into a recipient’s gut to restore normal flora in the recipient. The therapeutic principle on which FMT works is microbes and their functions and metabolites produced by them which are used to treat a variety of diseases. The present review focuses on the role of gastrointestinal microbiome, probiotic selection criteria, their applications and FMT to treat diseases.

Evaluation of the Cholesterol-Lowering Mechanism of Enterococcus faecium Strain 132 and Lactobacillus paracasei Strain 201 in Hypercholesterolemia Rats

Hypercholesterolemia can cause many diseases, but it can effectively regulated by Lactobacillus. This study aimed to evaluate the cholesterol-lowering mechanism of Enterococcus faecium strain 132 and Lactobacillusparacasei strain 201. These results showed that both the strains decreased serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), liver TC and TG and increased fecal TC, TG and total bile acid (TBA) levels. Additionally, both strains also reduced glutamic-pyruvic transaminase (ALT), glutamic oxaloacetic transaminase (AST) and levels of tissue inflammation levels to improve the lipid profile, and they reduced fat accumulation partially by alleviating inflammatory responses. Furthermore, both strains regulated the expression of the CYP8B1, CYP7A1, SREBP-1, SCD1 and LDL-R gene to promote cholesterol metabolism and reduce TG accumulation. Interventions with both strains also altered the gut microbiota, and decreasing the abundance of Veillonellaceae, Erysipelotrichaceae and Prevotella. Furthermore, fecal acetic acid and propionic acid were increased by this intervention. Overall, the results suggested that E. faecium strain 132 and L. paracasei strain 201 can alleviate hypercholesterolemia in rats and might be applied as a new type of hypercholesterolemia agent in functional foods.

Lactobacillus rhamnosus FJSYC4-1 and Lactobacillus reuteri FGSZY33L6 alleviate metabolic syndrome via gut microbiota regulation

Metabolic syndrome, which includes a series of metabolic disorders such as hyperglycemia, hyperlipidemia, insulin resistance and obesity, has become a catastrophic disease worldwide. Accordingly, probiotic intervention is a new strategy to alleviate metabolic syndrome, which can adjust the gut microbiota to a certain extent. The aim of the current work was to explore the alleviation of metabolic syndrome by Lactobacillus reuteri and L. rhamnosus. Two L. reuteri and two L. rhamnosus strains were administered to mice with a high-fat diet for 12 weeks. All Lactobacillus strains tested significantly slowed weight gain in the mice. Among four strains, L. reuteri FGSZY33L6 and L. rhamnosus FJSYC4-1 showed the strongest ability to relieve blood glucose disorders, blood lipid disorders, tissue damage, and particularly gut microbiota disorders. Thus, our findings indicate that these strains can regulate the gut microbiota and produce short-chain fatty acids (SCFAs), which can induce satiety hormones, inhibit food intake and increase satiety, and thus improve metabolic syndrome.

Current Trends of Enterococci in Dairy Products: A Comprehensive Review of Their Multiple Roles

As a genus that has evolved for resistance against adverse environmental factors and that readily exchanges genetic elements, enterococci are well adapted to the cheese environment and may reach high numbers in artisanal cheeses. Their metabolites impact cheese flavor, texture, and rheological properties, thus contributing to the development of its typical sensorial properties. Due to their antimicrobial activity, enterococci modulate the cheese microbiota, stimulate autolysis of other lactic acid bacteria (LAB), control pathogens and deterioration microorganisms, and may offer beneficial effects to the health of their hosts. They could in principle be employed as adjunct/protective/probiotic cultures; however, due to their propensity to acquire genetic determinants of virulence and antibiotic resistance, together with the opportunistic character of some of its members, this genus does not possess Qualified Presumption of Safety (QPS) status. It is, however, noteworthy that some putative virulence factors described in foodborne enterococci may simply reflect adaptation to the food environment and to the human host as commensal. Further research is needed to help distinguish friend from foe among enterococci, eventually enabling exploitation of the beneficial aspects of specific cheese-associated strains. This review aims at discussing both beneficial and deleterious roles played by enterococci in artisanal cheeses, while highlighting the need for further research on such a remarkably hardy genus.

Efficacy and Safety of Lactobacillus plantarum K50 on Lipids in Koreans With Obesity: A Randomized, Double-Blind Controlled Clinical Trial

BACKGROUND

Only few studies have investigated the role of probiotics in the development of obesity. We aimed to determine the efficacy and safety of an intake of Lactobacillus plantarum K50 (LPK) on body fat and lipid profiles in people with obesity.

METHODS

This randomized, double-blind, placebo-controlled, clinical trial involved 81 adults with a body mass index of 25-30 kg/m² who were assigned randomly to a diet including 4 × 10⁹ colony-forming unit of LPK or a placebo. Changes in body fat, anthropometric parameters, and biomarkers of obesity were compared using a linear mixed-effect model.

RESULTS

After 12 weeks of treatment, body weight, fat mass, and abdominal fat area did not change significantly in the two groups. However, total cholesterol levels decreased from 209.4 ± 34.4 mg/dL to 203.5 ± 30.9 mg/dL in the LPK group, but increased from 194.7 ± 37.5 mg/dL to 199.9 ± 30.7 mg/dL in the placebo group (P = 0.037). Similarly, triglyceride levels decreased from 135.4 ± 115.8 mg/dL to 114.5 ± 65.9 mg/dL in the LPK group, with a significant difference between groups. LPK supplementation also tended to decrease leptin levels compared with placebo. It also changed the distribution of gut microbiota significantly, with an increase in L. plantarum and a decrease in Actinobacteria, both of whose changes in abundance were correlated with changes in visceral adiposity, with borderline significance.

CONCLUSION

A 12-week consumption of LPK reduced the total cholesterol and triglyceride levels significantly with favorable alterations in microbiota, suggesting potential benefits for controlling blood lipid profiles.

Baseline gut microbiome composition predicts metformin therapy short-term efficacy in newly diagnosed type 2 diabetes patients

BACKGROUND

The study was conducted to investigate the effects of metformin treatment on the human gut microbiome's taxonomic and functional profile in the Latvian population, and to evaluate the correlation of these changes with therapeutic efficacy and tolerance.

METHODS

In this longitudinal observational study, stool samples for shotgun metagenomic sequencing-based analysis were collected in two cohorts. The first cohort included 35 healthy nondiabetic individuals (metformin dose 2x850mg/day) at three time-points during metformin administration. The second cohort was composed of 50 newly-diagnosed type 2 diabetes patients (metformin dose-determined by an endocrinologist) at two concordant times. Patients were defined as Responders if their HbA1c levels during three months of metformin therapy had decreased by ≥12.6 mmol/mol (1%), while in Non-responders HbA1c were decreased by <12.6 mmol/mol (1%).

RESULTS

Metformin reduced the alpha diversity of microbiota in healthy controls (p = 0.02) but not in T2D patients. At the species level, reduction in the abundance of Clostridium bartlettii and Barnesiella intestinihominis, as well as an increase in the abundance of Parabacteroides distasonis and Oscillibacter unclassified overlapped between both study groups. A large number of group-specific changes in taxonomic and functional profiles was observed. We identified an increased abundance of Prevotella copri (FDR = 0.01) in the Non-Responders subgroup, and enrichment of Enterococcus faecium, Lactococcus lactis, Odoribacter, and Dialister at baseline in the Responders group. Various taxonomic units were associated with the observed incidence of side effects in both cohorts.

CONCLUSIONS

Metformin effects are different in T2D patients and healthy individuals. Therapy induced changes in the composition of gut microbiome revealed possible mediators of observed short-term therapeutic effects. The baseline composition of the gut microbiome may influence metformin therapy efficacy and tolerance in T2D patients and could be used as a powerful prediction tool.

Anti-Proliferative and Anti-Biofilm Potentials of Bacteriocins Produced by Non-Pathogenic Enterococcus sp

The incidence of cancer is increasing worldwide; likewise, the emergence of antibiotic-resistant biofilm-forming pathogens has led to a tremendous increase in morbidity and mortality. This study aimed to evaluate the probiotic properties of bacteriocin-producing Enterococcus sp. with a focus on their anti-biofilm and anticancer activities. Three of 79 Enterococcus isolates (FM43, FM65, FM50) were identified as producers of broad-spectrum bioactive molecules and were molecularly characterized as Enterococcus faecium by 16S rRNA sequencing. Phenotypic and genotypic screening for potential virulence factors revealed no factors known to promote pathogenicity. Treatment with proteinase K resulted in diminished antimicrobial activity; PCR-based screening for bacteriocin genes suggested the presence of both entA and entB genes that encode enterocins A and B, respectively. Maximum antimicrobial activity was detected during the early stationary phase, while activity disappeared after 24 h in culture. Bacteriocins from these isolates were stable at high temperatures and over a wide range of pH. Interestingly, crude supernatants of Ent. faecium FM43 and Ent. faecium FM50 resulted in significant destruction (80% and 48%, respectively; P < 0.05) of Streptococcus mutans ATCC 25175-associated preformed biofilms. Moreover, in vitro cytotoxicity assays revealed that extracts from Ent. faecium isolates FM43, FM65, and FM50 inhibited Caco-2 cell proliferation by 76.9%, 70%, and 85.3%, respectively. Taken together, the multifunctional capabilities of the microbial-derived proteins identified in our study suggest potentially important roles as alternative treatments for biofilm-associated infections and cancer.

Association between the gut and oral microbiome with obesity

In recent decades, obesity has become one of the most common lifestyle-associated disorders. Obesity is a major contributing factor for several other lifestyles associated disorders such as type 2 diabetes mellitus, hypertension, and cardiovascular disease. Although genetics and lifestyle have been directly implicated in the onset and progression of obesity, recent studies have established that gut microbiome plays a crucial role in obesity progression. A higher proportion of Firmicutes and a skewed Firmicutes/Bacteroidetes ratio may contribute to gut dysbiosis and subsequent disturbances in the overall body metabolisms. Like gut microbiome, the oral cavity of humans also harbors a characteristic microbial population called "oral microbiome". The oral microbiome has also been implicated in the development of obesity due to its modulating effects on the gut microbiome. Due to its critical role in obesity, alteration in the gut microbiome has been suggested as one of the therapeutic strategies to manage obesity itself. For example, fecal microbiome transfer, or the use of probiotics and prebiotics have been suggested. These therapies not only restore the gut microbiome to the "pre-obese stage" but also ameliorate many functional aspects of the metabolic syndrome such as systemic inflammation, insulin resistance, and fat accumulation. However, the efficacy and safety of some of the methods have not been tested for their long-term implications, and further research in this area is warranted to understand the molecular mechanisms involved in this process completely.

Histamine and cholesterol lowering abilities of lactic acid bacteria isolated from artisanal Pico cheese

AIMS

This study was designed to select lactic acid bacteria with histamine- and cholesterol-reducing abilities to be used as potential probiotics.

METHODS AND RESULTS

Thirty strains of lactic acid bacteria isolated from an artisanal raw milk cheese were screened for their abilities to degrade histamine, reduce cholesterol and hydrolyse bile salts. Strains were also screened for safety and probiotic traits, such as resistance to gastrointestinal conditions, adhesion to Caco-2 cells, resistance to antibiotics and presence of virulence genes. Two Lactobacillus paracasei strains presented high cholesterol- and histamine-lowering abilities, tested negative for the presence of virulence genes and showed susceptibility to most important antibiotics. These strains were also shown to possess desirable in vitro probiotic properties, revealed by tolerance to gastrointestinal conditions and high adhesion to intestinal cells.

CONCLUSIONS

Among the screened strains, Lb. paracasei L3C21M6 revealed the best cholesterol and histamine reducing abilities together with desirable probiotic and safety features to be used in food applications.

SIGNIFICANCE AND IMPACT OF THE STUDY

The strain L3C21M6 is a good candidate for use as a probiotic with histamine-degrading activity and cholesterol lowering effect. In addition, this strain could be use in dairy foods to prevent histamine food poisoning.

Enterococcus hirae WEHI01 isolated from a healthy Chinese infant ameliorates the symptoms of type 2 diabetes by elevating the abundance of Lactobacillales in rats

Enterococcus hirae WEHI01 is a potential probiotic strain isolated from a healthy Chinese infant. This strain has previously been characterized as having cholesterol-lowering potential and good dairy fermentation performance. In this study, we used rat models with obesity and type 2 diabetes mellitus (T2DM) induced by a high fat and sucrose diet and low-dose streptozotocin, respectively, and we evaluated the effect of E. hirae WEHI01 on glycolipid metabolism, glycolipid-related gene expression, organ histopathology, and intestinal flora changes in the 2 models. Our results showed that administration of 5.0 × 109 cfu of E. hirae WEHI01 for 4 wk decreased serum lipid levels and regulated glycolipid metabolism in the liver of obese rats. Following continuous administration of the same concentration of E. hirae WEHI01 to a T2DM rat model for another 5 wk, E. hirae WEHI01 improved glucose tolerance, recovered body weight loss, and led to significant decreases in tumor necrosis factor-α, IL-6, IL-10, and total bile acid in serum. We also found that E. hirae WEHI01 restored the morphology of the pancreas, kidney, and liver, and changed the composition of the gut microbiota (i.e., decreased the Shannon index, increased the Simpson index, and substantially increased the abundance of Lactobacillales). Combining the results for the obese model and the T2DM model, we speculated that beneficial effects of E. hirae WEHI01 on T2DM could be due to (1) a significant increase in PPARA expression and a tendency for increased CYP7A1 expression in the liver of obese rats, promoting the conversion of cholesterol into bile acid and reducing serum total bile acid levels in T2DM model rats; or (2) a change in gut microbial diversity, especially elevated Lactobacillales abundance, which reduced the total bile acid in T2DM model rats. These results demonstrated that E. hirae WEHI01 has the potential to ameliorate type 2 diabetes in rats and provide a promising rationale for further research into the prevention and treatment of T2DM.

In vivo anti-hypercholesterolemic effect of buttermilk, milk fat globule membrane and Enterococcus faecium FFNL-12

The present study was undertaken to evaluate the hypocholesterolemic activity of buttermilk, milk fat globule membrane (MFGM) and Enterococcus faecium FFNL-12 in rat model. Thirty-sixth male Abino rats were divided into six groups. The first one (coded as G1) was fed a standard diet containing 10% corn oil as fat source while remaining five (coded G2 to G6) were fed hypercholesterolemic diets in which oil was replaced with animal grease. Animals subjected to treatment G1 served as healthy control while those in G2 were assigned as hypocholesterolemic animals which did not receive any treatment. The remaining experimental groups were designed to assess the hypocholesterolemic effect of intragastric adminstartion of dose of 109 CFU/Kg body weight of Enterococcus faecium FFNL-12 (G3), Enterococcus faecium FFNL-12/butter milk (G4), buttermilk (G5) and milk fat globule membrane (MFGM). After four weeks, animals were evaluated in relation to growth, fecal pH, organs weight, serum lipid profile, antioxidant activity of liver tissue, liver and heart function and liver histopathological architecture. Results revealed that animals fed hypercholesterolemic diet (G2-G6) had significantly lower faecal pH and liver weight compared with those fed standard diet (G1). Treatments applied to animals fed hypercholesterolemic diet with the above mentioned additions (G3 to G6) appeared to improve both cardiac and hepatic functions, serum lipid profile and glucose concentration and liver histopathological architecture compared with animals subjected to G2 treatment. In most cases, treatment with MFGM appeared to be the most effective to avoid adverse effects associated to feeding hypercholesterolemic diet. MFGM fraction as well as E. faecium FFNL-12/buttermilk combination were effective in reducing serum lipids and glucose levels to the normal range. This combination also had potential antioxidant activity and ability to improve liver and heart functions.