Antidiabetic effects of multi-species probiotic and its fermented milk in mice via restoring gut microbiota and intestinal barrier

Exploring the anti-obesity effects of Lactobacillus in C57BL/6 mice: mechanisms, interventions, and future directions

Lactobacillus species show strong potential in fighting obesity-related inflammation and metabolic issues. Obesity causes inflammation in adipose tissue, which harms insulin sensitivity and leads to fat buildup. Lactobacillus strains like Lactobacillus gasseri, Lactobacillus reuteri, and Lactobacillus plantarum help regulate lipid metabolism by boosting key genes, preventing fat cell formation, and encouraging fat breakdown. They also produce short-chain fatty acids (SCFAs) that improve gut health, activate metabolic pathways, and reduce inflammation. Studies in animals have shown that Lactobacillus can reduce body weight, fat, and inflammation, with Lactobacillus plantarum being especially effective in improving gut microbiota and liver function. When combined with other probiotics or prebiotics, these strains work even better, enhancing lipid metabolism and reducing inflammation. These results suggest that Lactobacillus could be an effective way to manage obesity and related health problems by influencing metabolism, gut health, and inflammation. However, more research, particularly human clinical trials, is needed to confirm its potential as a dietary treatment for obesity.

Lactiplantibacillus plantarum N1 derived lipoteichoic acid alleviates insulin resistance in association with modulation of the gut microbiota and amino acid metabolism

This study aimed to investigate the effects of heat-killed Lactiplantibacillus plantarum N1 (HK-N1) and lipoteichoic acid (LTA) derived from it on alleviating insulin resistance by modulating the gut microbiota and amino acid metabolism. High-fat diet (HFD)-fed mice were administered live bacteria or HK-N1, and the results demonstrated that HK-N1 significantly reduced epididymal adipocyte size and serum low density lipoprotein-cholesterol, and improved insulin resistance by increasing the YY peptide and glucagon-like peptide levels. HK-N1 also modulated the gut microbiome composition, enhancing microbiota uniformity and reducing the abundance of Ruminococcus, Oscillospira and norank_f_Mogibacteriaceae. Three main active substances obtained from HK-N1 (membrane protein, peptidoglycan, and lipoteichoic acid) were also used to investigate their potential effects in hyperglycemic zebrafish. Only LTA reduced blood sugar and altered the gut microbiome, particularly reducing Aeromonas, which is positively related to hyperglycemia. Untargeted metabolomics revealed that LTA improved vitamin and amino acid metabolism, thereby alleviating metabolic disorders in zebrafish. Collectively, our findings indicate that HK-N1, primarily through LTA, modulated insulin sensitivity by regulating the gut microbiota and amino acid metabolism, offering a potential therapeutic strategy for insulin resistance and type 2 diabetes mellitus.

Valorization of Bioactive Compounds from Lingonberry Pomace and Grape Pomace with Antidiabetic Potential

In recent years, increased attention has been paid to the recovery of bioactive compounds from waste and by-products resulting from the agro-industrial sector and their valorization into new products, which can be used in the health, food, or agricultural industry, as innovative and sustainable approaches to waste management. In this work, two of these by-products resulting from the fruit-processing industry were used for the recovery of bioactive compounds (polyphenols), namely lingonberry pomace (Vaccinium vitis-idaea) and grape pomace (Vitis vinifera). Two green extraction techniques were employed to obtain hydroalcoholic extracts (solvent: 50% EtOH, 10% mass): ultrasound-assisted extraction (UAE) and accelerated solvent extraction (ASE). The extracts were subjected to micro- and ultrafiltration processes, and further analyzed to determine the bioactive compound content through spectrophotometric (UV-Vis) and chromatographic (HPLC-PDA) methods. Additionally, the extracts exhibited significant enzyme inhibition, particularly against α-amylase and β-glucosidase, suggesting potential anti-diabetic properties. The extracts characteristics, polyphenolic content, antioxidant capacity and enzyme inhibitory ability, were statistically compared, and significant differences were found between the two extraction methods. The grape pomace concentrated extracts showed a pronounced inhibitory activity on both analyzed enzymes compared to the lingonberry pomace concentrated extracts, closer to the standard used; e.g., IC50 α-amylase = 0.30 ± 0.01 µg/mL (IC50 acarbose = 0.3 ± 0.01 µg/mL), IC50 α-glucosidase = 0.60 ± 0.01 µg/mL (IC50 acarbose = 0.57 ± 0.02 µg/mL). These findings highlight the potential of agro-industrial residues as bioactive compound resources, with their valorization through application in food, nutraceutical, or pharmaceutical industries therefore contributing to the sustainable development and promotion of circular economy principles with the recovery of valuable inputs from plant by-products.

Probiotic powder with polysaccharides from Wolfiporia cocos alleviates antibiotic-associated diarrhea by modulating immune activities and gut microbiota

To enhance immunomodulatory effects of lyophilized probiotics, we screened a new lyophilizing protective agent, that is Wolfiporia cocos polysaccharide (WP). This study demonstrated WP significantly increased the survival rate among seven polysaccharides, with the optimal dosage being 10 % (w/v). The ratio of bacterial suspension to lyophilizing protective agent was 1:2, in the condition, the probiotic survival rate of probiotics reached 83.06 %. Probiotic powder with WP (PWP) showed superior improvement in immune regulation and gut microbiota in antibiotic-associated diarrhea (AAD) mice compared to powder without WP. It notably increased IgM, IgG and IgA contents, and enhanced the activity of macrophage cells in the abdominal cavity. Furthermore, PWP exhibited the combined benefits of both the WP and PP in regulating the gut microbiota homeostasis, inhibiting the dysbiosis of the gut microbiota reflected in a significant increase in Proteobacteria, such as Sutterella, and decrease in Bacteroidetes, such as Muribaculaceae induced by AAD. Additionally, the correlation analysis indicated Sutterella had negative correlations with the immunomodulatory activities, meanwhile Muribaculace had positive correlations with the immunomodulatory activities. Overall, PWP could regulate the abundances of gut microbiota, thereby modulating immune activities and alleviating antibiotic-associated diarrhea, providing valuable insights for the development and application of WP in probiotics.

Latilactobacillus sakei QC9 alleviates hyperglycaemia in high-fat diet and streptozotocin-induced type 2 diabetes mellitus mice via the microbiota-gut-liver axis

Probiotics have been considered a promising option for mitigating the progression of type 2 diabetes mellitus (T2DM). Here, Latilactobacillus sakei QC9 (L. sakei QC9) with a hypoglycemic effect was screened out from 30 food-derived strains through α-glucosidase and α-amylase activity inhibition tests in vitro and a 4-week in vivo preliminary animal experiment. To further understand its alleviating effect on long-term hyperglycaemia occurring in T2DM, we conducted an experiment that lasted for 8 weeks. The results showed that taking L. sakei QC9 can regulate glucose and lipid metabolism while improving the antioxidant capacity and alleviating chronic inflammation. In addition, our results demonstrated that L. sakei QC9 may mediate the microbiota-gut-liver axis by regulating the composition of intestinal flora (increasing the abundance of butyrate-producing bacteria) and increasing the content of short-chain fatty acids (especially butyrate), affecting the PI3K/Akt signalling pathway in the liver, thereby achieving the purpose of alleviating the development of T2DM. In summary, our work is the first to prove the long-term hypoglycemic effect of L. sakei in high-fat diet (HFD) and streptozotocin (STZ)-induced T2DM mice and supports the possibility of L. sakei QC9 being used as a new treatment for alleviating T2DM.

Polyfunctional sugar-free white chocolate fortified with Lacticaseibacillus rhamnosus GG co-encapsulated with beet residue extract (Beta vulgaris L.)

Chocolate is a worldwide consumed food. This study investigated the fortification of sugar-free white chocolate with Lacticaseibacillus rhamnosus GG microcapsule co-encapsulated with beet residue extract. The chocolates were evaluated for moisture, water activity, texture, color properties, melting, physicochemical, and probiotic stability during storage. Furthermore, the survival of L. rhamnosus GG and the bioaccessibility of phenolic compounds were investigated under in vitro simulated gastrointestinal conditions. Regarding the characterization of probiotic microcapsules, the encapsulation efficiency of L. rhamnosus GG was > 89 % while the encapsulation efficiency of phenolic compounds was > 62 %. Chocolates containing probiotic microcapsules were less hard and resistant to breakage. All chocolates had a similar melting behavior (endothermic peaks between 32.80 and 34.40 °C). After 120 days of storage at 4 °C, probiotic populations > 6.77 log CFU/g were detected in chocolate samples. This result demonstrates the potential of this matrix to carry L. rhamnosus GG cells. Regarding the resistance of probiotic strains during gastric simulation, the co-encapsulation of L. rhamnosus GG with beet extract contributed to high counts during gastrointestinal transit, reaching the colon (48 h) with viable cell counts equal to 11.80 log CFU/g. Finally, one of our main findings was that probiotics used phenolic compounds as a substrate source, which may be an observed prebiotic effect.

Bifidobacterium improves oestrogen-deficiency-induced osteoporosis in mice by modulating intestinal immunity

Osteoporosis has become one of the major diseases that threaten the health of middle-aged and elderly people, and with the growth of an ageing population, more and more people are affected by osteoporosis these days. In recent years, intestinal flora has been found to affect the host immune system, and an overactive immune system is closely related to bone resorption. Probiotics can effectively improve bone density and strength, reduce bone loss, and improve osteoporosis, but their mechanism of action and relationship with intestinal microbiota are still unclear. In this study, two strains of Bifidobacterium (Bifidobacterium bifidum FL228.1 and Bifidobacterium animalis subsp. Lactis F1-7) that can alleviate intestinal inflammation were screened based on previous experiments. Through the construction of an ovariectomized mouse model, the improvement of osteoporosis by Bifidobacterium was detected, and the influence of Bifidobacterium on intestinal immunity was explored. The results show that Bifidobacterium treatment significantly improved bone mineral density (BMD), bone volume/total volume ratio (BV/TV), and trabecular number (Tb·N), and effectively suppressed bone loss. Furthermore, Bifidobacterium treatment could inhibit the expression of inflammatory cytokines in the gut, alleviate gut inflammation, and thus suppress excessive osteoclast generation. Its mechanism of action includes factors that protect the mucosal barrier, including occludin, ZO-1, claudin-2, and MUC2, and the reduction of pro-inflammatory M1 macrophages. B. bifidum FL228.1 increased the abundance of beneficial bacteria in the colon, including Lactobacillus and Colidextribacter. B. animalis F1-7 increased the abundance of Bifidobacterium and decreased the abundance of Desulfovibrio and Ruminococcus in the colon. These research findings expand our understanding of the gut-bone axis and provide new guidance for the development of probiotic-based therapies for osteoporosis in the future.

In Vitro Hypoglycemic Activities of Lactobacilli and Bifidobacterium Strains from Healthy Children's Sources and Their Effect on Stimulating GLP-1 Secretion in STC-1 Cells

A long-term use of chemical drugs cannot cure type II diabetes mellitus (T2DM) and their numerous toxic side effects can be harmful to human health. In recent years, probiotics have emerged as a natural resource to replace chemical drugs in alleviating many human ailments. Healthy children's intestines have a lot of colonized Lactobacilli and Bifidobacterium, and these beneficial bacteria can help promote overall health. The objective of this study was to isolate potential antidiabetic probiotic strains from healthy children and evaluate their application prospects. Firstly, Lactobacillus and Bifidobacterium strains were isolated from healthy children's feces and identified by the pheS or clpC genes with their respective 16S rRNA genes. Then, hydrophobicity, artificial gastrointestinal fluid tolerance, α-Glucosidase and Dipeptidyl peptidase IV (DPP-IV) inhibitory activities of isolated strains were determined, and antioxidant activities and promoting secretion of GLP-1 in STC-1 cells of candidate strains were tested. Results showed that 6 strains of Lactobacillus and Bifidobacterium were obtained from the feces of healthy children aged 3 years, respectively, including Lacticaseibacillus paracasei L-21 and L-25, Levilactobacillus brevis L-16, Lentilactobacillus buchneri L-9, Lactiplantibacillus plantarum L-8 and L-3, Bifidobacterium bifidum 11-1 and B-84, Bifidobacterium longum subsp. longum 6-1, 6-2, B42 and B53. The hydrophobicity and auto-aggregation levels of all these strains were higher than 30% and 50%, respectively, and the decrease in the number of colonies of all strains in the artificial gastrointestinal fluid was less than 2 log CFU/mL. Strains L-3, L-8, L-9, L-21, 6-1, 11-1, B53 and B84 were selected based on their high α-glucosidase inhibitory activity and DPP-IV inhibitory activity, and results of the antioxidant capacity assay showed that the remaining strains all had intense comprehensive antioxidant activity. Additionally, Lacticaseibacillus paracasei L-21 and Bifidobacterium longum subsp. longum B-53 had the most substantial prompting effect on GLP-1 secretion in the STC-1 cell line. These results indicated that Lacticaseibacillus paracasei L-21 and Bifidobacterium longum subsp. longum B-53 could be used as a potential antidiabetic strain; thus, its application as a food supplement and drug ingredient could be recommended after in vivo mitigation of type II diabetes test.

Proanthocyanidins-Based Synbiotics as a Novel Strategy for Nonalcoholic Fatty Liver Disease (NAFLD) Risk Reduction

Nonalcoholic fatty liver disease (NAFLD), the most common liver disease worldwide, is a spectrum of liver abnormalities ranging from steatosis to nonalcoholic steatohepatitis (NASH) characterized by excessive lipid accumulation. The prevalence of NAFLD is predicted to increase rapidly, demanding novel approaches to reduce the global NAFLD burden. Flavonoids, the most abundant dietary polyphenols, can reduce the risk of NAFLD. The majority of dietary flavonoids are proanthocyanidins (PACs), which are oligomers and polymers of the flavonoid sub-group flavan-3-ols. The efficacy of PAC in reducing the NAFLD risk can be significantly hindered by low bioavailability. The development of synbiotics by combining PAC with probiotics may increase effectiveness against NAFLD by biotransforming PAC into bioavailable metabolites. PAC and probiotic bacteria are capable of mitigating steatosis primarily through suppressing de novo lipogenesis and promoting fatty acid β-oxidation. PAC and probiotic bacteria can reduce the progression of steatosis to NASH mainly through ameliorating hepatic damage and inflammation induced by hepatic oxidative stress, endoplasmic reticulum stress, and gut microbiota dysbiosis. Synbiotics of PAC are superior in reducing the risk of NAFLD compared to independent administration of PAC and probiotics. The development of PAC-based synbiotics can be a novel strategy to mitigate the increasing incidence of NAFLD.

Membrane Emulsification as an Emerging Method for Lacticaseibacillus rhamnosus GG® Encapsulation

Techniques capable of producing small-sized probiotic microcapsules with high encapsulation yields are of industrial and scientific interest. In this study, an innovative membrane emulsification system was investigated in the production of microcapsules containing Lacticaseibacillus rhamnosus GG® (Lr), sodium alginate (ALG), and whey protein (WPI), rice protein (RPC), or pea protein (PPC) as encapsulating agents. The microcapsules were characterized by particle size distribution, optical microscopy, encapsulation yield, morphology, water activity, hygroscopicity, thermal properties, Fourier-transform infrared spectroscopy (FTIR), and probiotic survival during in vitro simulation of gastrointestinal conditions. The innovative encapsulation technique resulted in microcapsules with diameters varying between 18 and 29 μm, and encapsulation yields > 93%. Combining alginate and whey, rice, or pea protein improved encapsulation efficiency and thermal properties. The encapsulation provided resistance to gastrointestinal fluids, resulting in high probiotic viability at the end of the intestinal phase (> 7.18 log CFU g-1). The proposed encapsulation technology represents an attractive alternative to developing probiotic microcapsules for future food applications.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11947-023-03099-w.

Lactobacillus paracasei IMC 502 ameliorates type 2 diabetes by mediating gut microbiota-SCFA-hormone/inflammation pathway in mice

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a complex and prevalent metabolic disease that seriously threatens human health. Numerous studies have shown that probiotics as dietary supplements have the potential to prevent and treat T2DM. However, the ability of various strains to improve diabetes symptoms and corresponding mechanisms are different. Thus, mechanistic investigation is required to validate the pharmacology of each probiotic strain for T2DM treatment. Lactobacillus paracasei IMC 502 was originally isolated from Italian elderly human feces and its probiotic attributes have been demonstrated. Here, the antidiabetic pharmacodynamics of L. paracasei IMC 502 on T2DM mice was explored.

RESULTS

Lactobacillus paracasei IMC 502 significantly decreased blood glucose, HbA1c and lipid levels, improved insulin resistance and glucose intolerance, regulated the mRNA/protein expression of key hepatic enzymes associated with gluconeogenesis, de novo lipogenesis and PI3K/Akt pathway, and repaired pancreatic and hepatic tissue damage. This probiotic conferred beneficial outcomes in the gut microbiome of diabetic mice, which induced transformation of short-chain fatty acids (SCFAs) and further enhanced the secretion of downstream hormones, and ultimately ameliorated the inflammatory response.

CONCLUSION

Lactobacillus paracasei IMC 502 prevents and alleviates T2DM by mediating the gut microbiota-SCFA-hormone/inflammation pathway. © 2022 Society of Chemical Industry.

Fermented natural product targeting gut microbiota regulate immunity and anti-inflammatory activity: A possible way to prevent COVID-19 in daily diet

Low immune function makes the body vulnerable to being invaded by external bacteria or viruses, causing influenza and inflammation of various organs, and this trend is shifting to the young and middle-aged group. It has been pointed out that natural products fermented by probiotic have benign changes about their active ingredients in some studies, and it have shown strong nutritional value in anti-oxidation, anti-aging, regulating lipid metabolism, anti-inflammatory and improving immunity. In recent years, the gut microbiota plays a key role and has been extensively studied in improving immunity and anti-inflammation activity. By linking the relationship between natural products fermented by probiotic, gut microbiota, immunity, and inflammation, this review presents the modulating effects of probiotics and their fermented natural products on the body, including immunity-enhancing and anti-inflammatory activities by modulating gut microbiota, and it is discussed that the current understanding of its molecular mechanisms. It may become a possible way to prevent COVID-19 through consuming natural products fermented by probiotic in our daily diet.