Youth-derived Lactobacillus rhamnosus with prebiotic xylo-oligosaccharide exhibits anti-hyperlipidemic effects as a novel synbiotic

Changes in dietary patterns and living habits have led to an increasing number of individuals with elevated cholesterol levels. Excessive consumption of high-cholesterol foods can disrupt the body's lipid metabolism. Numerous studies have firmly established the cholesterol-lowering effects of probiotics and prebiotics, with evidence showing that the synergistic use of synbiotics is functionally more potent than using probiotics or prebiotics alone. Currently, the screening strategy involves screening prebiotics for synbiotic development with probiotics as the core. However, in comparison to probiotics, there are fewer types of prebiotics available, leading to limited resources. Consequently, the combinations of synbiotics obtained are restricted, and probiotics and prebiotics are only relatively suitable. Therefore, in this study, a novel synbiotic screening strategy with prebiotics as the core was developed. The synbiotic combination of Lactobacillus rhamnosus S_82 and xylo-oligosaccharides was screened from the intestinal tract of young people through five generations of xylo-oligosaccharides. Subsequently, the cholesterol-lowering ability of the medium was simulated, and the two carbon sources of glucose and xylo-oligosaccharides were screened out. The results showed that synbiotics may participate in cholesterol-lowering regulation by down-regulating the expression of NPC1L1 gene, down-regulating ACAT2 and increasing the expression of ABCG8 gene in vitro through cell adsorption and cell absorption in vitro, and regulating the intestinal microbiota. Synbiotics hold promise as potential candidates for the prevention of hypercholesterolemia in humans and animals, and this study providing a theoretical foundation for the development of new synbiotic products.

Gut microbes, diet, and genetics as drivers of metabolic liver disease: a narrative review outlining implications for precision medicine

Metabolic dysfunction-associated steatotic liver disease (MASLD) is rapidly increasing in prevalence, impacting over a third of the global population. The advanced form of MASLD, Metabolic dysfunction-associated steatohepatitis (MASH), is on track to become the number one indication for liver transplant. FDA-approved pharmacological agents are limited for MASH, despite over 400 ongoing clinical trials, with only a single drug (resmetirom) currently on the market. This is likely due to the heterogeneous nature of disease pathophysiology, which involves interactions between highly individualized genetic and environmental factors. To apply precision medicine approaches that overcome interpersonal variability, in-depth insights into interactions between genetics, nutrition, and the gut microbiome are needed, given that each have emerged as dynamic contributors to MASLD and MASH pathogenesis. Here, we discuss the associations and molecular underpinnings of several of these factors individually and outline their interactions in the context of both patient-based studies and preclinical animal model systems. Finally, we highlight gaps in knowledge that will require further investigation to aid in successfully implementing precision medicine to prevent and alleviate MASLD and MASH.

Daily koumiss has positive regulatory effects on blood lipids and immune system: A metabolomics study

Koumiss, a traditional Mongolian beverage, is believed to possess high nutritional value and potential medical benefits. However, there is a lack of comprehensive research on its potential impact on the human body. Metabolomics, as a sensitive approach in systems biology, offers a new avenue for studying the overall effects of koumiss. In this work, metabolomics was utilized to identify potential biomarkers and pathways associated with koumiss using UPLC-MS detection, pattern recognition analysis, pathway enrichment, network pharmacology. The findings indicated that koumiss exerts a beneficial regulatory influence on lipid metabolism, neurotransmitters, hormones, phospholipids and arachidonic acid metabolism, besides up regulating the content of nutrients. It could reduce the risks of dyslipidemia and inflammatory responses. This study confirmed the benign regulatory effect of koumiss on normal organism from the perspective of endogenous metabolites, and provided objective support for the promotion and application of this ethnic food.

Bile acid metabolism in health and ageing-related diseases

Bile acids (BAs) have surpassed their traditional roles as lipid solubilizers and regulators of BA homeostasis to emerge as important signalling molecules. Recent research has revealed a connection between microbial dysbiosis and metabolism disruption of BAs, which in turn impacts ageing-related diseases. The human BAs pool is primarily composed of primary BAs and their conjugates, with a smaller proportion consisting of secondary BAs. These different BAs exert complex effects on health and ageing-related diseases through several key nuclear receptors, such as farnesoid X receptor and Takeda G protein-coupled receptor 5. However, the underlying molecular mechanisms of these effects are still debated. Therefore, the modulation of signalling pathways by regulating synthesis and composition of BAs represents an interesting and novel direction for potential therapies of ageing-related diseases. This review provides an overview of synthesis and transportion of BAs in the healthy body, emphasizing its dependence on microbial community metabolic capacity. Additionally, the review also explores how ageing and ageing-related diseases affect metabolism and composition of BAs. Understanding BA metabolism network and the impact of their nuclear receptors, such as farnesoid X receptor and G protein-coupled receptor 5 agonists, paves the way for developing therapeutic agents for targeting BA metabolism in various ageing-related diseases, such as metabolic disorder, hepatic injury, cardiovascular disease, renal damage and neurodegenerative disease.

Kefir as a therapeutic agent in clinical research: a scoping review

Increasing research has been conducted on the role of probiotics in disease treatment. Kefir, a safe, low-cost probiotic fermented milk drink, has been investigated in many in vitro and animal studies, although parameters for human therapeutic dose or treatment time have not yet been determined. Here we perform a scoping review of clinical studies that have used kefir as a therapeutic agent, compiling the results for perspectives to support and direct further research. This review was based on Joanna Briggs Institute guidelines, including studies on the effects of kefir-fermented milk in humans. Using the term KEFIR, the main international databases were searched for studies published in English, Spanish or Portuguese until 9 March 2022. A total of 5835 articles were identified in the four databases, with forty-four eligible for analysis. The research areas were classified as metabolic syndrome and type 2 diabetes, gastrointestinal health/disorders, maternal/child health and paediatrics, dentistry, oncology, women's and geriatric health, and dermatology. The many study limitations hampered generalisation of the results. The small sample sizes, methodological variation and differences in kefir types, dosage and treatment duration prevented clear conclusions about its benefits for specific diseases. We suggest using a standard therapeutic dose of traditionally prepared kefir in millilitres according to body weight, making routine consumption more feasible. The studies showed that kefir is safe for people without serious illnesses.

Diagnostic utility of selected faecal biochemical parameters in the determination of acute diarrhoea and associated defecation stooling characteristics in dogs: An observational study

Diarrhoea, which is a clinical manifestation of various illnesses, is frequently observed in dogs. Regrettably, many dog owners find it difficult to provide comprehensive case histories, primarily because of limited interaction with their canine companions. This study aimed to evaluate the potential of faecal biochemical analytes in detecting and characterizing acute diarrhoea in dogs. Sixty-two domestic dogs were selected using the proportionate stratified sample technique. A structured questionnaire was used to collect demographic and clinical data. Faecal stool specimens from the dogs were obtained using the colon flush technique. The specimens were taken through biochemical analysis to determine urea, creatinine, total bilirubin, total cholesterol, triglycerides, gamma-glutamyl transferase and uric acid levels. Results showed a significant association between the diarrhoea status of the participants and their age, weight, breed, body size, source of last diet, period of inappetence, and other gastrointestinal signs (p < 0.050, respectively). Dogs that had not eaten in at least three days were five times more likely (p < 0.05) to have diarrhoea. Furthermore, miniature breeds were about six times more likely to develop diarrhoea (p < 0.05). Of the seven selected biochemical parameters, total faecal cholesterol was the most predictive index in diagnosing acute diarrhoea in dogs, with a likelihood ratio of 6.5, and it was the most accurate in predicting defecation stooling frequency and texture. In summary, in situations of inadequate case histories, measuring total faecal cholesterol could assist veterinarians in detecting diarrhoea and predicting its faecal stooling texture and frequency in dogs.

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.

Microbiome-modulating nutraceuticals ameliorate dyslipidemia in type 2 diabetes: A systematic review, meta-analysis, and meta-regression of clinical trials

AIMS

Type 2 Diabetes is intrinsically linked to cardiovascular disease (CVD) via diabetic dyslipidemia, both of which remain global health concerns with annually increasing prevalence. Given the established links between gut microbiome dysbiosis and metabolic diseases, its modulation is an attractive target to ameliorate metabolic imbalances in such patients. There is a need to quantitively summarise, analyse, and describe future directions in this field.

METHODS

We conducted a systematic review, meta-analysis, and meta-regression following searches in major scientific databases for clinical trials investigating the effect of pro/pre/synbiotics on lipid profile published until April 2022. Data were pooled using random-effects meta-analysis and reported as mean differences with 95% confidence intervals (CIs). PROSPERO No. CRD42022348525.

RESULTS

Data from 47 trial comparisons across 42 studies (n = 2692) revealed that, compared to placebo/control groups, the administration of pro/pre/synbiotics was associated with statistically significant changes in total cholesterol (-9.97 mg/dL [95% CI: -15.08; -4.87], p < 0.0001), low-density lipoprotein (-6.29 mg/dL [95% CI: -9.25; -3.33], p < 0.0001), high-density lipoprotein (+3.21 mg/dL [95% CI: 2.20; 4.22], p < 0.0001), very-low-density lipoprotein (-4.52 mg/dL [95% CI: -6.36; -2.67], p < 0.0001) and triglyceride (-22.93 mg/dL [95% CI: -33.99; -11.87], p < 0.001). These results are influenced by patient characteristics such as age or baseline BMI, and intervention characteristics such as dosage and duration.

CONCLUSIONS

Our study shows that adjunct supplementation with a subset of pro/pre/synbiotics ameliorates dyslipidemia in diabetic individuals and has the potential to reduce CVD risk. However, widespread inter-study heterogeneity and the presence of several unknown confounders limit their adoption in clinical practice; future trials should be designed with these in mind.

A meta-analysis of the therapeutic effect of probiotic intervention in obese or overweight adolescents

Background & aims

Existing evidence on the possible effects of probiotics on obese or overweight adolescents has not been fully established. Therefore, the aim of this study was to explore the effects of probiotic supplementation on anthropometric indices, inflammatory markers and metabolic indices in obese or overweight adolescents.

Methods

The literature up to March 2023 related to probiotic intervention in obese or overweight adolescents was searched and screened from multiple databases, including the CNKI(China national knowledge infrastructure), CBM(Chinese biomedical literature database), PubMed, EmBase, and Cochrane library databases. All randomized controlled trials using probiotic supplements in obese or overweight adolescents were included in this systematic review and meta-analysis.

Results

A total of 8 studies that met the inclusion criteria were included in this study. There were 201 cases in the experimental group (probiotic treatment) and 190 cases in the control group. Compared to the control group, probiotic intervention in adolescents resulted in a decrease in body mass index, fasting blood glucose and C-reactive protein with WMD(Weighted mean difference) and 95% CI of -2.53 (-4.8 to -0.26) kg/m2, -0.80 (-1.13 to -0.47) mol/L and -0.24 (-0.43 to -0.05) mg/L, respectively. No significant changes were found in weight, waist circumference, waist-to-hip ratio, insulin, Homeostatic Model Assessment of insulin resistance, interleukin 6, tumor necrosis factor alpha and so on; however, an unfavorable elevated effect in total cholesterol, triglycerides, and low-density lipoproteins was detected with WMD and 95% CI of 0.06 (0.02 to 0.09) mmol/L, 0.18 (0.14 to 0.21) mmol/L, and 0.19 (0.18 to 0.20) mmol/L, respectively.

Conclusion

According to our results, probiotic supplementation was beneficial in managing metabolic indicators such as fasting blood glucose, body mass index and inflammation-related C-reactive protein in overweight or obese adolescents. Further large scale studies are warranted to confirm present findings and to identify the effects and mechanisms to provide more precise evidence for clinical intervention.

Systematic review registration

doi: 10.37766/inplasy2024.1.0081, identifier INPLASY202410081.

The Role of Autochthonous Levilactobacillus brevis B1 Starter Culture in Improving the Technological and Nutritional Quality of Cow's Milk Acid-Rennet Cheeses-Industrial Model Study

In the study, an attempt was made to develop an innovative technology for cheese manufacturing. It was hypothesized that selected autochthonous lactic acid bacteria as a starter culture are more suitable for the production of acid-rennet cheeses of good technological and sensory quality. The study aimed to assess the possibility of using the strain Levilactobacillus brevis B1 (L. brevis B1) as a starter culture to produce acid-rennet cheeses using raw cow's milk. Two variants of cheese were manufactured. The control variant (R) was coagulated with microbial rennet and buttermilk, and the other variant (B1) was inoculated with rennet and L. brevis B1 starter culture. The effect of the addition of these autochthonous lactic acid bacteria on selected physicochemical characteristics, durability, the composition of fatty acids, cholesterol, Iipid Quality Indices, and microbiological and sensory quality of acid-rennet cheeses was determined during a 3-month period of storage. The dominant fatty acids observed in the tested cheeses were saturated fatty acids (SFA) (68.43-69.70%) and monounsaturated fatty acids (MUFA) (25.85-26.55%). Significantly higher polyunsaturated fatty acid (PUFA) content during storage was observed for B1 cheeses. The B1 cheeses were characterized by lower cholesterol content compared to cheese R and showed better indexes, including the Index of atherogenicity, Index of thrombogenicity, DFA, OFA, H/H, and HPI indexes, than the R cheese. No effect of the tested L. brevis B1 on sensory quality was observed in relation to the control cheeses during 3 months of storage. The results of the research indicate the possibility of using the L. brevis B1 strain for the production of high-quality, potentially probiotic acid-rennet cheeses.

Safety assessment of potential probiotic Lactobacillus acidophilus AM13-1 with high cholesterol-lowering capability isolated from human gut

An important risk factor for cardiovascular disease is dyslipidemia, especially abnormal cholesterol levels. The relation between probiotics and cholesterol-lowering capability has been extensively studied. Lactobacillus acidophilus plays a significant role in affecting host health, and produces multitudinous metabolites, which have prohibitory functions against pathogenic microorganisms. In this study, we identified a cholesterol-lowering strain AM13-1, isolated from a fecal sample obtained from a healthy adult male, and performed comprehensive function analysis by whole-genome analysis and in vitro experiments. Genome analyses of L. acidophilus AM13-1 revealed that carbohydrate and amino acid transport, metabolism, translation, ribosomal structure, and biogenesis are abundant categories of functional genes. No virulence factors or toxin genes with experimentally verified were found in the genome of strain AM13-1. Besides, plenty of probiotic-related genes were predicted from the L. acidophilus AM13-1 genome, such as cbh, atpA-D, and dltD, with functions related to cholesterol-lowering and acid resistance. And strain AM13-1 showed high-efficiency of bile salt hydrolase activity and the capacity for removing cholesterol with efficiency rates of 70%. These function properties indicate that strain AM13-1 can be considered as a probiotic candidate for use in food and health care products.

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.

Effects of antibiotic, acidifier, and probiotic supplementation on mortality rates, lipoprotein profile, and carcass traits of broiler chickens

Antimicrobial resistance is a significant issue, therefore it's relevant to assess the effects of antibiotics, acidifiers, and probiotic supplementation finding a good alternative to reduce the use of antibiotics in broiler production in rural areas of Bangladesh. Using randomized control trial, this 28-day study evaluated 360 Hubbard Classic broiler chicks divided into four groups: oxytetracycline-treated, acidifier-treated, Lactobacillus-based probiotic-treated, and control (no antibiotics, acidifiers, or probiotics). Each group was replicated three times with 30 birds each with adlibitum feeding. Body weight and feed intake were recorded weekly, and on 28th day, carcass traits and blood lipoprotein levels were evaluated. Results showed that in first and fourth weeks, the body weight gain significantly varied in probiotics and acidifier-treated birds than the control group (P < 0.001). The probiotic group had gained considerable increase in body weight (185.0 g vs 161.7 g and 1745.0 g vs 1592.7 g) than the control group. Notably, in the first week, the feed conversion ratio for the probiotic group was 0.76, but the antibiotic group's was 0.96 (P < 0.001). The weights of the drumstick (88.33 g) and liver (61.0 g) having probiotic supplements were substantially higher than those in the control group (77.0 g and 51.33 g, respectively) (P < 0.001). According to serum lipoprotein analysis, the probiotic and acidifier groups exhibited lower LDL levels (71.1 mg/dl and 69.8 mg/dl, respectively) and higher triglyceride levels (122.9 mg/dl and 135.4 mg/dl). These findings highlight the potential of probiotics and acidifiers as effective antibiotic alternatives, promoting carcass traits and lowering LDL levels in broilers in Bangladesh.

Nutritional ingredients and prevention of chronic diseases by fermented koumiss: a comprehensive review

Koumiss, a traditional fermented dairy product made from fresh mare milk, is a sour beverage that contains an abundance of microbial communities, including lactic acid bacteria, yeast and others. Firstly, probiotics such as Lacticaseibacillus in koumiss can induce the secretion of immunoglobulin G in serum and interleukin-2 in the spleen while beneficial Saccharomyces can secrete antibacterial compounds such as citric acid and ascorbic acid for specific immunopotentiation. Additionally, more isoflavone in koumiss can regulate estrogen levels by binding to its receptors to prevent breast cancer directly. Bile salts can be converted into bile acids such as taurine or glycine by lactic acid bacteria to lower cholesterol levels in vivo. Butyric acid secretion would be increased to improve chronic gastrotis by regulating intestinal flora with lactic acid bacteria. Finally, SCFA and lCFA produced by Lacticaseibacillus inhibit the reproduction of pathogenic microorganisms for diarrhea prevention. Therefore, exploring the mechanisms underlying multiple physiological functions through utilizing microbial resources in koumiss represents promising avenues for ameliorating chronic diseases.

Ameliorating effects of L-carnitine and synbiotic co-supplementation on anthropometric measures and cardiometabolic traits in women with obesity: a randomized controlled clinical trial

Background

Obesity, a multifactorial disorder with pandemic dimensions, is conceded a major culprit of morbidity and mortality worldwide, necessitating efficient therapeutic strategies. Nutraceuticals and functional foods are considered promising adjuvant/complementary approaches for weight management in individuals with obesity who have low adherence to conventional treatments. Current literature supports the weight-reducing efficacy of pro/pre/synbiotics or L-carnitine; however, the superiority of the nutraceutical joint supplementation approach over common single therapies to counter obesity and accompanying comorbidities is well documented. This study was designed to assess the effects of L-carnitine single therapy compared with L-carnitine and multistrain/multispecies synbiotic co-supplementation on anthropometric and cardiometabolic indicators in women with obesity.

Methods

The current placebo-controlled double-blind randomized clinical trial was performed on 46 women with obesity, randomly allocated to either concomitant supplementation [L-carnitine tartrate (2 × 500 mg/day) + multistrain/multispecies synbiotic (1 capsule/day)] or monotherapy [L-carnitine tartrate (2 × 500 mg/day) + maltodextrin (1 capsule/day)] groups for 8 weeks. Participants in both groups received healthy eating dietary advice.

Results

Anthropometric, lipid, and glycemic indices significantly improved in both intervention groups; however, L-carnitine + synbiotic co-administration elicited a greater reduction in the anthropometric measures including body mass index (BMI), body weight, and neck, waist, and hip circumferences (p < 0.001, <0.001, <0.001, = 0.012, and =0.030, respectively) after adjusting for probable confounders. Moreover, L-carnitine + synbiotic joint supplementation resulted in a greater reduction in fasting blood sugar (FBS), insulin (though marginal), and homeostatic model assessment of insulin resistance (HOMA-IR) and more increment in quantitative insulin sensitivity check index (QUICKI; p = 0.014, 0.051, 0.024, and 0.019, respectively) compared with the L-carnitine + placebo monosupplementation. No significant intergroup changes were found for the lipid profile biomarkers, except for a greater increase in high-density lipoprotein-cholesterol concentrations (HDL-C) in the L-carnitine + synbiotic group (p = 0.009).

Conclusion

L-carnitine + synbiotic co-supplementation was more beneficial in ameliorating anthropometric indices as well as some cardiometabolic parameters compared with L-carnitine single therapy, suggesting that it is a promising adjuvant approach to ameliorate obesity or associated metabolic complications through potential synergistic or complementary mechanisms. Further longer duration clinical trials in a three-group design are demanded to verify the complementary or synergistic mechanisms.

Clinical trial registration

www.irct.ir, Iranian Registry of Clinical Trials IRCT20080904001197N13.

Exercise Training and Probiotic Lacticaseibacillus rhamnosus GG Reduce Tetracycline-Induced Liver Oxidative Stress and Inflammation in Rats with Hepatic Steatosis

Lifestyle modification with regular exercise can improve metabolic diseases by reducing lipid profile and inflammation. Probiotics have been recently recommended not only for gastrointestinal diseases but also for metabolic and even degenerative diseases. Therefore, in the present study, the effect of high-intensity interval training (HIIT) and Lacticaseibacillus rhamnosus strain GG (LGG) as a probiotic on tetracycline-induced hepatic steatosis in an animal model was evaluated. Eighty male Wistar rats were randomly divided into eight groups (n = 10 in each group): control, LGG, HIIT, LGG + HIIT, tetracycline-induced (TTC), TTC + LGG, TTC + HIIT, and TTC + LGG + HIIT. The rats are treated by intraperitoneal injection (IP) with 140 mg kg-1 tetracycline, an antibiotic previously known to induce steatosis. The exercise training groups performed HIIT 5 days/week for 5 weeks, and 107 CFU/ml of Lacticaseibacillus rhamnosus GG was gavaged for the LGG groups 5 days/week for 5 weeks. Fatty droplets in the hepatocyte were considered with Oil Red staining. TTC-receiving rats have more lipid accumulation and larger lipid droplets in the liver compared to healthy animals. The two-way ANOVA showed that the interaction of LGG and HIIT significantly decreased LDL, cholesterol, and triglyceride in the healthy rats (p < 0.05). In TTC-receiving rats, the interaction of LGG and HIIT significantly increased HDL and SOD and significantly decreased triglyceride, ALP, AST, and ALT (p < 0.05). The consumption of probiotic LGG, along with HIIT with control of lipid profile and liver enzymes and improvement of the oxidative capacity, neutralizes the damage of TTC to liver tissue. Therefore, this protocol can be recommended for people with hepatic steatosis.

High-fat diet impact on intestinal cholesterol conversion by the microbiota and serum cholesterol levels

Cholesterol-to-coprostanol conversion by the intestinal microbiota has been suggested to reduce intestinal and serum cholesterol availability, but the relationship between intestinal cholesterol conversion and the gut microbiota, dietary habits, and serum lipids has not been characterized in detail. We measured conserved proportions of cholesterol high and low-converter types in individuals with and without obesity from two distinct, independent low-carbohydrate high-fat (LCHF) dietary intervention studies. Across both cohorts, cholesterol conversion increased in previous low-converters after LCHF diet and was positively correlated with the fecal relative abundance of Eubacterium coprostanoligenes. Lean cholesterol high-converters had increased serum triacylglycerides and decreased HDL-C levels before LCHF diet and responded to the intervention with increased LDL-C, independently of fat, cholesterol, and saturated fatty acid intake. Our findings identify the cholesterol high-converter type as a microbiome marker, which in metabolically healthy lean individuals is associated with increased LDL-C in response to LCHF.

Effects of gut microbial therapy on lipid profile in individuals with non-alcoholic fatty liver disease: an umbrella meta-analysis study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), the most common liver disease, is closely associated with metabolic conditions such as obesity and diabetes mellitus, which significantly impact human health outcomes. The impaired lipid profiles observed in NAFLD individuals can further contribute to cardiovascular events. Despite the high prevalence of NAFLD, there is currently no confirmed intervention approved for its treatment. This study aimed to summarize the results of meta-analysis studies of randomized control trials assessing the impact of gut microbial therapy (probiotics, synbiotics, and prebiotics) on the lipid profile of individuals with NAFLD.

METHODS

A systematic search was conducted on PubMed, Scopus, Web of Science, and Cochrane Library up to November 1, 2022. Meta-analyses surveying the impact of microbial therapy on lipid profile parameters (triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and total cholesterol (TC)) in the NAFLD population were included in our umbrella review. The final effect size (ES) was estimated, and sensitivity and subgroup analyses were performed to explore heterogeneity.

RESULTS

Fifteen studies were included in this umbrella review. Microbial therapy significantly reduced TG (ES - 0.31, 95% CI - 0.51, - 0.11, P < 0.01), TC (ES - 1.04, 95% CI - 1.46, - 0.61, P < 0.01), and LDL (ES - 0.77, 95% CI - 1.15, - 0.39, P < 0.01) in individuals with NAFLD. However, the effect on HDL was not statistically significant (ES - 0.06; 95% CI - 0.19, 0.07, P = 0.39).

CONCLUSION

Considering the absence of approved treatments for NAFLD and the promising role of microbial therapies in improving the three lipid profiles components in individuals with NAFLD, the use of these agents as alternative treatment options could be recommended. The findings underscore the potential of gut microbial therapy, including probiotics, synbiotics, and prebiotics, in managing NAFLD and its associated metabolic complications.

TRIAL REGISTRATION

PROSPERO ( CRD42022346998 ).

Autochthonous Bacilli and Fructooligosaccharide as Functional Feed Additives Improve Growth, Feed Utilisation, Haemato-Immunological Parameters and Disease Resistance in Rohu, Labeo rohita (Hamilton)

The effects of Bacillus spp. (7 Log CFU g-1 feed) and fructooligosaccharide (FOS, 1%) as functional feed additives, either alone or in combination, were evaluated in a study on rohu, Labeo rohita fingerlings. The fish were fed different diets for 90 days, including a control diet and diets supplemented with FOS, B. licheniformis, B. methylotrophicus or synbiotic formulations of these. The results showed that the combination of B. licheniformis and FOS significantly improved weight gain, feed utilisation and protease activity compared to the other groups. Overall, the groups supplemented with probiotics and synbiotics (B. licheniformis + FOS or B. methylotrophicus + FOS) showed improvements in haematology, serum biochemistry and immune parameters compared to the control group. After 90 days of experimental feeding, the fish were challenged with pathogenic Aeromonas hydrophila, and data on haematology, immunity and stress parameters were collected. The results indicated that the application of Bacillus spp. and FOS boosted immunity and resistance to physiological stress in the fish. The highest post-challenge survival rate was observed in fish fed a diet with B. licheniformis and FOS, indicating the potential of this particular combination of functional feed additives to enhance growth, immunity and disease resistance in L. rohita.

bsh1 Gene of Lactobacillus plantarum AR113 Plays an Important Role in Ameliorating Western Diet-Aggravated Colitis

Western diet is thought to increase susceptibility to inflammatory bowel disease (IBD), and probiotics are a potential therapeutic agent for IBD. This study revealed the effects of Lactobacillus plantarum AR113 and L. plantarum AR113Δbsh1 on a dextran sulfate sodium (DSS)-induced colitis mouse model under the Western diet (WD). After four weeks of WD and low-sugar and low-fat diet (LD) intervention, induction with 3% DSS, and intragastric administration of probiotics, we found that L. plantarum AR113 could regulate blood glucose and lipid levels and have a certain protective effect on hepatocytes. Our results suggested that the L. plantarum AR113 alleviated DSS-induced colitis under the Western diet by improving dyslipidemia, repairing intestinal barrier dysfunction, and inhibiting the TLR4/Myd88/TRAF-6/NF-κB inflammatory pathway. However, these changes were not demonstrated in the L. plantarum AR113Δbsh1, and therefore, we reasoned that the presence of bsh1 may play a crucial role in the L. plantarum AR113 exerting its anti-inflammatory function. The relationship between bile salt hydrolase (BSH) and colitis was worthy of further exploration.

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.

The Expression Levels of Genes Responsible for the Enzymatic Activity of Bile Salt Hydrolase (BSH) and the Relationship of Cholesterol Assimilation in L. plantarum and L. paracasei

The bile salt hydrolase (BSH) activity is responsible for the cholesterol-lowering effect of the probiotic strains. The present study aimed to investigate the relationship between bsh gene-expression (GE) levels responsible for the BSH activity and the parameters of bile salt resistance of different Lactobacillaceae species. Accordingly, 11 Lactobacillaceae family strains with high cholesterol assimilation ratio (49.21-68.22%) determined by the o-phthalaldehyde method selected from 46 Lactobacillaceae species was evaluated for their features including acid tolerance, bile tolerance, and BSH activity. All tested strains survived at pH 2 medium and 0.3% (w/v) bile salt and showed positive BSH activity for glycocholic acid (GCA) and taurocholic acid (TCA). BSH gene expression was performed to provide clear information and to identify the key genes responsible for BSH activity. bsh3 genes were found highest GE level (P < 0.05) in Lactiplantibacillus plantarum and Lacticaseibacillus paracasei strains. The results showed that high cholesterol assimilation ratio were closely correlated with BSH activity and the parameters of bile salt resistance. The results of this study will support the development of a new approach based on phenotypic and genetic analysis to determine the bile salt parameters. The study will be useful for the selection of Lactobacillus strains with high bile salt resistance.

Evaluation of the survival of homofermentative Lacticaseibacillus casei subsp. casei in fermented milk matrix enriched with non-digestible natural fibers

The physicochemical changes induced by seven different dietary fibers (oat, bamboo, pea, inulin, apple, potato, and wheat) during storage and their effects on the survival of homofermentative Lacticaseibacillus casei subsp. casei (L. casei) in fermented milk matrix were analyzed. For this, an experimental study of the effect of storage time on the microorganisms count and physicochemical properties (pH, titratable acidity, syneresis and viscosity) of milk fermented with L. casei was carried out every two weeks during a storage period of 42 days. Throughout the period studied at 4 °C, no significant differences were found in terms of viscosity values, syneresis rates and L. casei counts, despite the substantial decrease in the pH values. Notably, the substantial increase in the concentration of free hydronium ions (active acidity) in the fiber-enriched matrices during the follow-up period was positively correlated with the L.casei survival. The microbial count determined in all samples was higher than 1 × 107 CFU/g, the minimum value recommended by world organizations for nutraceutical fermented foods. Consequently, the studied prebiotic fibers could be considered in the production of new fermented dairy products with functional properties.

Graphical abstract

Comparison of the effects of probiotic-based formulations on growth, feed utilization, blood constituents, cecal fermentation, and duodenal morphology of rabbits reared under hot environmental conditions

The present study aimed to assess the effects of three probiotic-supplemented diets on growth, cecal fermentation, blood biochemical, and intestinal morphological features in growing rabbits reared under summer conditions. Rabbits were allotted into four groups: G1 rabbits were fed the basal diet (control), G2 rabbits received Enterococcus faecium (EF) and Clostridium butyricum (CB) complexes (1 × 108 and 2.5 × 106 cfu/kg diet, respectively), G3 rabbits were given CB (2.5 × 106 cfu/kg diet) and yeast complexes (1 g/kg diet), and G4 rabbits received EF (2 × 108 cfu/kg diet) and yeast (1 g/kg diet). G2 rabbits exhibited the highest performances in terms of enhanced body weight and weight gain, protein efficiency ratio and feed conversion ratio (P<0.05). Serum total protein, globulin, immunoglobulin M, and high-density lipoprotein concentrations were higher in probiotic-fed rabbits than those in controls. Additionally, lipid profile parameters were significantly reduced in the probiotic-fed rabbits, with the lowest concentrations measured in G4 rabbits (P<0.05). Rabbits given EF and CB had the highest total volatile fatty acid (VFA) and propionic acid levels and the lowest ammonia concentrations. Increased villi length and muscular layer thickness and reduced crypt depth were observed in rabbits receiving EF and CB compared with the values obtained in controls (P<0.05). In summary, supplementing fattening rabbit diets with EF and CB, as a novel formulation, might be a promising and easy method to enhance growth performance under hot climate conditions by improving the feed utilization, immune response, serum lipid profile, cecal VFA production, and duodenal morphology.

High cholesterol intake remodels cholesterol turnover and energy homeostasis in Nile tilapia (Oreochromis niloticus)

The roles of dietary cholesterol in fish physiology are currently contradictory. The issue reflects the limited studies on the metabolic consequences of cholesterol intake in fish. The present study investigated the metabolic responses to high cholesterol intake in Nile tilapia (Oreochromis niloticus), which were fed with four cholesterol-contained diets (0.8, 1.6, 2.4 and 3.2%) and a control diet for eight weeks. All fish-fed cholesterol diets showed increased body weight, but accumulated cholesterol (the peak level was in the 1.6% cholesterol group). Then, we selected 1.6% cholesterol and control diets for further analysis. The high cholesterol diet impaired liver function and reduced mitochondria number in fish. Furthermore, high cholesterol intake triggered protective adaptation via (1) inhibiting endogenous cholesterol synthesis, (2) elevating the expression of genes related to cholesterol esterification and efflux, and (3) promoting chenodeoxycholic acid synthesis and efflux. Accordingly, high cholesterol intake reshaped the fish gut microbiome by increasing the abundance of Lactobacillus spp. and Mycobacterium spp., both of which are involved in cholesterol and/or bile acids catabolism. Moreover, high cholesterol intake inhibited lipid catabolic activities through mitochondrial β-oxidation, and lysosome-mediated lipophagy, and depressed insulin signaling sensitivity. Protein catabolism was elevated as a compulsory response to maintain energy homeostasis. Therefore, although high cholesterol intake promoted growth, it led to metabolic disorders in fish. For the first time, this study provides evidence for the systemic metabolic response to high cholesterol intake in fish. This knowledge contributes to an understanding of the metabolic syndromes caused by high cholesterol intake or deposition in fish.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42995-022-00158-7.

Antibiotic-induced gut microbiota depletion exacerbates host hypercholesterolemia

Hypercholesterolemia is a major driver of atherosclerosis, thus contributing to high morbidity and mortality worldwide. Gut microbiota have been identified as modulator of blood lipids including cholesterol levels. Few studies have already linked certain bacteria and microbial mechanisms to host cholesterol. However, in particular mouse models revealed conflicting results depending on genetics and experimental protocol. To gain further insights into the relationship between intestinal bacteria and host cholesterol metabolism, we first performed fecal 16S rRNA targeted metagenomic sequencing in a human cohort (n = 24) naïve for cholesterol lowering drugs. Here, we show alterations in the gut microbiota composition of hypercholesterolemic patients with depletion of Bifidobacteria, expansion of Clostridia and increased Firmicutes/Bacteroidetes ratio. To test whether pharmacological intervention in gut microbiota impacts host serum levels of cholesterol, we treated hypercholesterolemic Apolipoprotein E knockout with oral largely non-absorbable antibiotics. Antibiotics increased serum cholesterol, but only when mice were fed normal chow diet and cholesterol was measured in the random fed state. These elevations in cholesterol already occurred few days after treatment initiation and were reversible after stopping antibiotics with re-acquisition of intestinal bacteria. Gene expression analyses pointed to increased intestinal cholesterol uptake mediated by antibiotics in the fed state. Non-targeted serum metabolomics suggested that diminished plant sterol levels and reduced bile acid cycling were involved microbial mechanisms. In conclusion, our work further enlightens the link between gut microbiota and host cholesterol metabolism. Pharmacological disruption of the gut flora by antibiotics was able to exacerbate serum cholesterol and may impact cardiovascular disease.

Alterations in Healthy Adult Canine Faecal Microbiome and Selected Metabolites as a Result of Feeding a Commercial Complete Synbiotic Diet with Enterococcus faecium NCIMB 10415

In dogs, the use of probiotics for preventive or therapeutic purposes has become increasingly common, however the evidence for beneficial effects are often limited. The aim of this study was to investigate the effects of feeding a diet containing Enterococcus faecium NCIMB 10415 on faecal quality, faecal short-chain fatty acid concentrations, serum concentrations of cholesterol, triglycerides, cobalamin and folate as well as faecal microbiome in adult dogs. Eleven healthy client owned dogs were enrolled in a randomized, double-blinded crossover study. All dogs were fed the same balanced diet with or without incorporation of Enterococcus faecium NCIMB 10415 for 16 days each. Blood and faecal samples were collected at baseline and during the feeding trial and owners recorded daily faecal scores. An Enterococcus spp. ASV, likely representing E. faecium NCIMB 10415 was detected in the faecal microbiome of some dogs 18-19 days after withdrawal of oral supplementation. Inclusion of E. faecium decreased circulating cholesterol (p = 0.008) compared to baseline. There were no differences in cholesterol concentrations between diets. Owners reported 0.6 ± 0.3) days less of loose stools compared to the control diet. Comparing to baseline, both diets significantly increased faecal concentration of acetate and butyrate, decreased serum cobalamin and increased faecal microbial diversity. Decreased serum cobalamin, and increased faecal acetate correlated with decreases in the Fusobacterium, Streptococcus, Blautia, and Peptoclostridium. Except for effects on circulating cholesterol and faecal score, effects were observed regardless of the addition of E. faecium. It is therefore likely that these effects can be contributed to dietary prebiotic effects on the faecal microbiome.

Diversified Shifts in the Cross Talk between Members of the Gut Microbiota and Development of Coronary Artery Diseases

Coronary artery disease (CAD) is one of leading causes of mortality worldwide. Studies on roles that the gut microbiota plays in development of atherosclerosis or acute myocardial infarction (AMI) have been widely reported. However, the gut microbiota is affected by many factors, including age, body mass index (BMI), and hypertension, that lead to high CAD risk. However, the associations between gut microbiota and CAD development or other CAD risk factors remain unexplored. Here, we performed a 16S RNA gene sequencing analysis of 306 fecal samples collected from patients with mild coronary stenosis (MCS; n = 36), stable angina (SA; n = 91), unstable angina (UA; n = 48), and acute myocardial infarction (AMI; n = 66) and 65 non-CAD controls. Using a noise-corrected method based on principal-component analysis (PCA) and the random forest algorithm, we identified the interference with gut microbial profiling of multiple factors (including age, gender, BMI, and hypertension) that potentially contributed significantly to the development of CAD. After correction of noise interference from certain interfering factors, we found consistent indicator microbiota organisms (such as Vampirovibrio, Ruminococcus, and Eisenbergiella) associated with the presence of MCS, SA, and AMI. Establishment of a diagnostic model revealed better performance in early CAD than clinical indexes with indicator microbes. Furthermore, indicator microbes can improve the accuracy of clinical indexes for the diagnosis of AMI. Additionally, we found that the microbial indicators of AMI Sporobacter and Eisenbergiella showed consistent positive and negative correlations to the clinical indexes creatine kinase (CK) and hemoglobin (Hb), respectively. As a control indicator of AMI, Dorea was negatively correlated with CK but positively correlated with Hb. IMPORTANCE Our study discovered the effect of confounding factors on gut microbial variations and identified gut microbial indicators possibly associated with the CAD development after noise correction. Our discovered indicator microbes may have potential for diagnosis or therapy of cardiovascular disorders.

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.

Bifidobacterial carbohydrate/nucleoside metabolism enhances oxidative phosphorylation in white adipose tissue to protect against diet-induced obesity

BACKGROUND

Comparisons of the gut microbiome of lean and obese humans have revealed that obesity is associated with the gut microbiome plus changes in numerous environmental factors, including high-fat diet (HFD). Here, we report that two species of Bifidobacterium are crucial to controlling metabolic parameters in the Korean population.

RESULTS

Based on gut microbial analysis from 99 Korean individuals, we observed the abundance of Bifidobacterium longum and Bifidobacterium bifidum was markedly reduced in individuals with increased visceral adipose tissue (VAT), body mass index (BMI), blood triglyceride (TG), and fatty liver. Bacterial transcriptomic analysis revealed that carbohydrate/nucleoside metabolic processes of Bifidobacterium longum and Bifidobacterium bifidum were associated with protecting against diet-induced obesity. Oral treatment of specific commercial Bifidobacterium longum and Bifidobacterium bifidum enhanced bile acid signaling contributing to potentiate oxidative phosphorylation (OXPHOS) in adipose tissues, leading to reduction of body weight gain and improvement in hepatic steatosis and glucose homeostasis. Bifidobacterium longum or Bifidobacterium bifidum manipulated intestinal sterol biosynthetic processes to protect against diet-induced obesity in germ-free mice.

CONCLUSIONS

Our findings support the notion that treatment of carbohydrate/nucleoside metabolic processes-enriched Bifidobacterium longum and Bifidobacterium bifidum would be a novel therapeutic strategy for reprograming the host metabolic homeostasis to protect against metabolic syndromes, including diet-induced obesity. Video Abstract.

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.

Bile acids-gut microbiota crosstalk contributes to the improvement of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) occurs that cannot effectively use the insulin. Insulin Resistance (IR) is a significant characteristic of T2DM which is also an essential treatment target in blood glucose regulation to prevent T2DM and its complications. Bile acids (BAs) are one group of bioactive metabolites synthesized from cholesterol in liver. BAs play an important role in mutualistic symbiosis between host and gut microbiota. It is shown that T2DM is associated with altered bile acid metabolism which can be regulated by gut microbiota. Simultaneously, BAs also reshape gut microbiota and improve IR and T2DM in the bidirectional communications of the gut-liver axis. This article reviewed the findings on the interaction between BAs and gut microbiota in improving T2DM, which focused on gut microbiota and its debinding function and BAs regulated gut microbiota through FXR/TGR5. Meanwhile, BAs and their derivatives that are effective for improving T2DM and other treatments based on bile acid metabolism were also summarized. This review highlighted that BAs play a critical role in the glucose metabolism and may serve as therapeutic targets in T2DM, providing a reference for discovering and screening novel therapeutic drugs.

Precise strategies for selecting probiotic bacteria in treatment of intestinal bacterial dysfunctional diseases

Abundant microbiota resides in the organs of the body, which utilize the nutrition and form a reciprocal relationship with the host. The composition of these microbiota changes under different pathological conditions, particularly in response to stress and digestive diseases, making the microbial composition and health of the hosts body interdependent. Probiotics are living microorganisms that have demonstrated beneficial effects on physical health and as such are used as supplements to ameliorate symptoms of various digestive diseases by optimizing microbial composition of the gut and restore digestive balance. However, the supplementary effect does not achieve the expected result. Therefore, a targeted screening strategy on probiotic bacteria is crucial, owing to the presence of several bacterial strains. Core bacteria work effectively in maintaining microbiological homeostasis and stabilization in the gastrointestinal tract. Some of the core bacteria can be inherited and acquired from maternal pregnancy and delivery; others can be acquired from contact with the mother, feces, and the environment. Knowing the genera and functions of the core bacteria could be vital in the isolation and selection of probiotic bacteria for supplementation. In addition, other supporting strains of probiotic bacteria are also needed. A comprehensive strategy for mining both core and supporting bacteria before its clinical use is needed. Using metagenomics or other methods of estimation to discern the typically differentiated strains of bacteria is another important strategy to treat dysbiosis. Hence, these two factors are significant to carry out targeted isolation and selection of the functional strains to compose the resulting probiotic preparation for application in both research and clinical use. In conclusion, precise probiotic supplementation, by screening abundant strains of bacteria and isolating specific probiotic strains, could rapidly establish the core microbiota needed to confer resilience, particularly in bacterial dysfunctional diseases. This approach can help identify distinct bacteria which can be used to improve supplementation therapies.

Modulatory role of gut microbiota in cholesterol and glucose metabolism: Potential implications for atherosclerotic cardiovascular disease Atherosclerosis

Accumulating evidence suggests an important role of gut microbiota in physiological processes of host metabolism as well as cardiometabolic disease. Recent advances in metagenomic and metabolomic research have led to discoveries of novel pathways in which intestinal microbial metabolism of dietary nutrients is linked to metabolic profiles and cardiovascular disease risk. A number of metaorganismal circuits have been identified by microbiota transplantation studies and experimental models using germ-free rodents. Many of these pathways involve gut microbiota-related bioactive metabolites that impact host metabolism, in particular lipid and glucose homeostasis, partly via specific host receptors. In this review, we summarize the current knowledge of how the gut microbiome can impact cardiometabolic phenotypes and provide an overview of recent advances of gut microbiome research. Finally, the potential of modulating intestinal microbiota composition and/or targeting microbiota-related pathways for novel preventive and therapeutic strategies in cardiometabolic and cardiovascular diseases will be discussed.

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.

Hypolipidemic activity of lactic acid bacteria: Adjunct therapy for potential probiotics

Background

Individuals with hyperlipidemia are two times more likely to develop atherosclerotic cardiovascular disease (ASCVD) as opposed to those with controlled serum total cholesterol (TC) levels. Considering the documented adverse events of the current lipid-lowering medications which ultimately affect patient’s compliance, substantial efforts have been made to develop new therapeutic strategies. Probiotics, on the other hand, are reported to have lipid-lowering activity with the added benefit of being generally well-tolerated making it an appealing adjuvant therapy.

Methods

A total of fifty Lactic acid bacteria (LAB) were isolated from raw milk (human and animal) and dairy products. Isolates demonstrating promising in vitro cholesterol removal capabilities were morphologically and biochemically characterized. Lastly, two bacterial candidates were selected for evaluation of their potential hypolipidemic activity using a laboratory animal model. Statistical differences between the means were analyzed by one-way analysis of variance (ANOVA) followed by Tukey’s post-hoc test. A p-value < 0.05 was considered statistically significant.

Results

Most of the isolates demonstrated an in vitro cholesterol removal activity. The six LAB isolates showing the highest cholesterol removal activity (36.5–55.6%) were morphologically and biochemically identified as Lactobacillus, Pediococcus, and Lactococcus species. The results demonstrated two promising antihyperlipidemic candidates, a Lactococcus lactis ssp. lactis with an in vivo significant reduction of serum triglycerides (TG) levels by 34.3%, and a Pediococcus sp. that was able to significantly reduce both the serum TC and TG levels by 17.3% and 47.0%, respectively, as compared to the diet-induced hyperlipidemic animal group.

Conclusion

This study further supports the growing evidence regarding the antihyperlipidemic activity among probiotics, presenting them as a promising therapeutic approach for the management of hyperlipidemia.

Screening and Characterization of Some Lactobacillaceae for Detection of Cholesterol-Lowering Activities

Dyslipidemia, specifically abnormal levels of low-density lipoprotein cholesterol (LDL-C), is an important risk factor of cardiovascular disease. Evidence showing the promising abilities of probiotics to lower total cholesterol or LDL-C has, however, not yet convinced experts to recommend probiotic bacteria as treatment for blood lipid management. Therefore, there are opportunities for the development of new efficient cholesterol-lowering probiotics. Bile salt hydrolase (BSH) and feruloyl esterase (FAE) are bacterial enzymes proposed to explain the cholesterol-lowering capacity of some bacteria and have both been shown to be responsible for lipid reduction in vivo. Here, in order to select for cholesterol-lowering bacteria, 70 strains related to Lactobacillaceae were screened for BSH and FAE activities. Based on this two-way screening approach, two bacteria were selected and assessed for their capacity to assimilate cholesterol in vitro, another suggested mechanism. Lactobacillus acidophilus CL1285 showed BSH and FAE activity as well as capacity to assimilate cholesterol in vitro. Lactiplantibacillus plantarum CHOL-200 exhibited BSH activity and ability to assimilate cholesterol. These properties observed in vitro make both strains good probiotic candidates for the management of dyslipidemia. Further investigation is needed to assess their ability to reduce blood cholesterol in human trial.

Isomaltooligosaccharides utilization and genomic characterization of human infant anti-inflammatory Bifidobacterium longum and Bifidobacterium breve strains

This study was carried out to understand the probiotic features, ability to utilize non-digestible carbohydrates and comparative genomics of anti-inflammatory Bifidobacterium strains isolated from human infant stool samples. Bacterial strains were isolated from the stool samples using serial dilution on MRS agar plates supplemented with 0.05% l-cysteine hydrochloride and mupirocin. Molecular characterization of the strains was carried out by 16S rRNA gene sequencing. Anti-inflammatory activity was determined using TNF-α and lipopolysaccharide (LPS) induced inflammation in Caco2 cells. Probiotic attributes were determined as per the established protocols. Isomaltooligosaccharides (IMOS) utilization was determined in the broth cultures. Whole genome sequencing and analysis was carried out for three strains. Four obligate anaerobic, Gram positive Bifidobacterium strains were isolated from the infant stool samples. Strains were identified as Bifidobacterium longum Bif10, B. breve Bif11, B. longum Bif12 and B. longum Bif16. The strains were able to prevent inflammation in the Caco2 cells through lowering of IL8 production that was caused by TNF-α and LPS treatment. The strains exhibited desirable probiotic attributes such as acid and bile tolerance, mucin binding, antimicrobial activity, bile salt hydrolase activity, cholesterol lowering ability and could ferment non-digestible carbohydrates such as isomaltooligosaccharides and raffinose. Furthermore, Isomaltooligosaccharides supported the optimum growth of the strains in vitro, which was comparable to that on glucose. Strains could metabolize IMOS through cell associated α-glucosidase activity. Genomic features revealed the presence of genes responsible for the utilization of IMOS and for the probiotic attributes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03141-2.

The effect of probiotics on gestational diabetes and its complications in pregnant mother and newborn: A systematic review and meta-analysis during 2010-2020

This study was aimed to evaluate the effect of probiotics consumption on gestational diabetes (GD) and its complications in pregnant mother and newborn. The study was registered on PROSPERO (CRD42021243409) and all the enrolled articles were collected from four databases (Medline, Scopus, Embase, and Google Scholar) as randomized controlled trials (RCTs) from 2010 to 2020. A total of 4865 study participants from 28 selected studies were included in this review. The present meta‐analysis showed that the consumption of probiotics supplementation has the potential to decrease GD‐predisposing metabolic parameters such as blood glucose level, lipid profile, inflammation, and oxidative markers which may reduce GD occurrence among pregnant women.

Probiotics in prevention and treatment of cardiovascular diseases

Increasing knowledge of the gut microbiota and its interference in human homeostasis in recent years has contributed to a better understanding of number of different interactions occurring in the gastrointestinal tract. Disruption of the microbiota is detrimental to health and contributes to the development of numerous diseases and may also be an accelerator of pathophysiological processes such as atherosclerosis. Cardiovascular diseases are the most common cause of death worldwide, so the development of new methods to support the treatment and prevention of these diseases becoms one of the priorities of modern medicine. Probiotics may constitute an important element of support in the treatment and prevention of CVD (cardiovascular diseases). A number of papers support such a statement, however, larger clinical trials are needed. Through a number of mechanisms including mitigating inflammation, sealing the intestinal epithelium, and affecting metabolism, probiotics may have a beneficial effect on general health and slow down the pathogenesis of many diseases, including those affecting the cardiovascular system. This article contains a review of current discoveries on the role of probiotics in the prevention and support of CVD treatment.

Why Do These Microbes Like Me and How Could There Be a Link with Cardiovascular Risk Factors?

Cardiovascular diseases are the most common causes of hospitalization, death, and disability in Europe. Due to high prevalence and ensuing clinical complications, they lead to very high social and economic costs. Despite the knowledge of classical cardiovascular risk factors, there is an urgent need for discovering new factors that may play a role in the development of cardiovascular diseases or potentially influence prognosis. Recently, particular attention has been drawn to the endogenous microflora of the human body, mostly those inhabiting the digestive system. It has been shown that bacteria, along with their host cells, create an interactive ecosystem of interdependencies and relationships. This interplay could influence both the metabolic homeostasis and the immune processes of the host, hence leading to cardiovascular disease development. In this review, we attempt to describe, in the context of cardiovascular risk factors, why particular microbes occur in individuals and how they might influence the host’s cardiovascular system in health and disease.

Functional foods as a formulation ingredients in beverages: technological advancements and constraints

As a consequence of expanded science and technical research, the market perception of consumers has shifted from standard traditional to valuable foods, which are furthermore nutritional as well as healthier in today's world. This food concept, precisely referred to as functional, focuses on including probiotics, which enhance immune system activity, cognitive response, and overall health. This review primarily focuses on functional foods as functional additives in beverages and other food items that can regulate the human immune system and avert any possibility of contracting the infection. Many safety concerns must be resolved during their administration. Functional foods must have an adequate amount of specific probiotic strain(s) during their use and storage, as good viability is needed for optimum functionality of the probiotic. Thus, when developing novel functional food-based formulations, choosing a strain with strong technological properties is crucial. The present review focused on probiotics as an active ingredient in different beverage formulations and the exerting mechanism of action and fate of probiotics in the human body. Moreover, a comprehensive overview of the regulative and safety issues of probiotics-based foods and beverages formulations.

Nutritional and ethnomedicinal scenario of koumiss: A concurrent review

Fermented foods are an essential source of nutrition for the communities living in developing areas of the world. Additionally, traditional fermented products are a rich source of various bioactive components. Experimental research regarding the functional exploration of these products is a way forward for better human health. Among fermented foods, Koumiss is rich in vitamins especially vitamin C and minerals, i.e., phosphorus and calcium. In addition, it is also rich in vitamins A, E, B2, B12, and pantothenic acid. High concentrations of lactose in milk favor bacterial fermentation, as the original cultures decompose it into lactic acid. Koumiss contains essential fatty acids such as linoleic and linolenic acid. Koumiss offers many health benefits including boosting the immune system and maintains blood pressure, good effect on the kidneys, endocrine glands, gut system, liver, and nervous and vascular system. The rich microflora from the fermented product has a pivotal role in maintaining gut health and treating various digestive diseases. The core focus of the current review paper is to highlight the nutritional and therapeutic potential, i.e., anticarcinogenic, hypocholesterolemia effect, antioxidative properties, antibacterial properties, antibacterial spectrum, intestinal enlargement, and β-galactosidase activity, of Koumiss as a traditional fermented product. Moreover, history and production technology of the Koumiss are also the main part of this review paper.

Dietary Eicosapentaenoic Acid and Docosahexaenoic Acid Ethyl Esters Influence the Gut Microbiota and Bacterial Metabolites in Rats

Dietary fish oil containing eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) has been reported to affect the diversity and composition of gut microbiota and bacterial metabolites. However, few reports have focused on the effects of EPA and DHA on gut microbiota diversity and bacterial metabolites. This study evaluated the effects of dietary EPA-ethyl ester (EE) and DHA-EE on steroid metabolism, gut microbiota, and bacterial metabolites in Wistar rats. Male rats were fed the experimental diets containing 5% (w/w) soybean oil-EE (SOY diet), EPA-EE (EPA diet), and DHA-EE (DHA diet) for four weeks. The lipid contents in the serum and liver, mRNA expression levels in the liver, and the diversity, composition, and metabolites of the gut microbiota were evaluated. The EPA and DHA diets decreased serum and liver cholesterol contents compared to the SOY diet. In addition, there were no significant changes in gene expression levels related to steroid metabolism in the liver between the EPA and DHA groups. Rats fed the DHA diet had lower microbiota diversity indices, such as Simpson and Shannon indices, than rats fed the SOY and EPA diets. In addition, rats fed EPA and DHA had significant differences in the relative abundance of microbiota at the genus level, such as Phascolarctobacterium, Turicibacter, and [Eubacterium]. Therefore, it was concluded that EPA and DHA have different effects on the diversity and composition of gut microbiota under the experimental conditions employed herein.

Hepatic transcriptome analysis reveals altered lipid metabolism and consequent health indices in chicken supplemented with dietary Bifidobacterium bifidum and mannan-oligosaccharides

This study investigated the role of dietary prebiotic mannan-oligosaccharides (MOS), and probiotic Bifidobacterium bifidum (BFD) in lipid metabolism, deposition, and consequent health indices in broiler chicken. The supplementation of 0.2% MOS along with either 10⁶ or 10⁷ CFU BFD/g feed resulted in downregulation of Acetyl-CoA carboxylase, fatty acid synthase, sterolregulatory element binding protein-1, and apolipoprotein B100; and up-regulation of peroxisome proliferator activated receptor-α AMP-activated protein kinase α-1, and stearoyl CoA (∆9) desaturase-1 hepatic expression in broiler chicken. The birds supplemented with 0.2% MOS along with either 10⁶ or 10⁷ CFU BFD/g feed depicted lower body fat percentage, palmitic acid, stearic acid, and saturated fatty acid contents, whereas, higher palmitoleic acid, oleic acid, and MUFA contents were observed. The ∆9-desaturase indices of chicken meat have shown higher values; and elongase index (only thigh) and thioesterase index have shown lower values in birds supplemented with 0.2% MOS along with either 10⁶ or 10⁷ CFU BFD/g feed. The meat health indices such as Polyunsaturated fatty acids (PUFA)/Saturated fatty acids (SFA) ratio, Mono-saturated fatty acids (MUFA)/SFA ratio, unsaturated fatty acids (UFA)/SFA ratio, hypocholesterolemic/hypercholesterolemic fatty acid ratio, saturation index, atherogenic index, thrombogenic index, and hypercholesterolemic fatty acid content were positively improved in birds supplemented with 0.2% MOS along with either 10⁶ or 10⁷ CFU BFD/g feed. Similarly, the birds supplemented with 0.2% MOS along with either 10⁶ or 10⁷ CFU BFD/g feed have shown lower serum triglyceride and total cholesterol levels along with higher high density levels and improved serum health indices cardiac risk ratio, atherogenic coefficient, and, atherogenic index of plasma.