Probiotic Strain Bifidobacterium animalis subsp. lactis CECT 8145 Reduces Fat Content and Modulates Lipid Metabolism and Antioxidant Response in Caenorhabditis elegans

The Probiotic Strain Lactobacillus acidophilus CL1285 Reduces Fat Deposition and Oxidative Stress and Increases Lifespan in Caenorhabditis elegans

Caenorhabditis elegans was recently shown to be a powerful model for studying and identifying probiotics with specific functions. Lactobacillus acidophilus CL1285, Lacticaseibacillus casei LBC80R, and Lacticaseibacillus rhamnosus CLR2, which are three bacteria that were marketed by Bio-K+, were evaluated using the nematode C. elegans to study fat accumulation, lifespan, and resistance to oxidative stress. Although the general effects of probiotics in terms of protection against oxidative stress were highlighted, the CL1285 strain had an interesting and specific feature, namely its ability to prevent fat accumulation in nematodes; this effect was verified by both the Oil Red and Nile Red methods. This observed phenotype requires daf-16 and is affected by glucose levels. In addition, in a daf-16- and glucose-dependent manner, CL1285 extended the lifespan of C. elegans; this effect was unique to CL1285 and not found in the other L. acidophilus subtypes in this study. Our findings indicate that L. acidophilus CL1285 impacts fat/glucose metabolism in C. elegans and provides a basis to further study this probiotic, which could have potential health benefits in humans and/or in mammals.

Potential probiotic Lactobacillus delbrueckii subsp. lactis KUMS-Y33 suppresses adipogenesis and promotes osteogenesis in human adipose-derived mesenchymal stem cell

Today, probiotics are considered to be living microorganisms whose consumption has a certain number of beneficial effects on the consumer. The present study aimed to investigate the effect of a new probiotic extract (Lactobacillus delbrueckii subsp. lactis KUMS Y33) on the differentiation process of human adipose-derived stem cells (hADSCs) into adipocytes and osteocytes and, as a result, clarify its role in the prevention and treatment of bone age disease. Several bacteria were isolated from traditional yogurt. They were evaluated to characterize the probiotic's activity. Then, the isolated hADSCs were treated with the probiotic extract, and then osteogenesis and adipogenesis were induced. To evaluate the differentiation process, oil red O and alizarin red staining, a triglyceride content assay, an alkaline phosphatase (ALP) activity assay, as well as real-time PCR and western blot analysis of osteocyte- and adipocyte-specific genes, were performed. Ultimately, the new strain was sequenced and registered on NBCI. In the probiotic-treated group, the triglyceride content and the gene expression and protein levels of C/EBP-α and PPAR-γ2 (adipocyte-specific markers) were significantly decreased compared to the control group (P < 0.05), indicating an inhibited adipogenesis process. Furthermore, the probiotic extract caused a significant increase in the ALP activity, the expression levels of RUNX2 and osteocalcin, and the protein levels of collagen I and FGF-23 (osteocyte-specific markers) in comparison to the control group (P < 0.05), indicating an enhanced osteogenesis process. According to the results of the present study, the probiotic extract inhibits adipogenesis and significantly increases osteogenesis, suggesting a positive role in the prevention and treatment of osteoporosis and opening a new aspect for future in-vivo study.

Geroprotective potential of microbiome modulators in the Caenorhabditis elegans model

Aging is associated with cellular and physiological changes, which significantly reduce the quality of life and increase the risk for disease. Geroprotectors improve lifespan and slow the progression of detrimental aging-related changes such as immune system senescence, mitochondrial dysfunction, and dysregulated nutrient sensing and metabolism. Emerging evidence suggests that gut microbiota dysbiosis is a hallmark of aging-related diseases and microbiome modulators, such as probiotics (live bacteria) or postbiotics (non-viable bacteria/bacterial byproducts) may be promising geroprotectors. However, because they are strain-specific, the geroprotective effects of probiotics and postbiotics remain poorly understood and understudied. Drosophila melanogaster, Caenorhabditis elegans, and rodents are well-validated preclinical models for studying lifespan and the role of probiotics and/or postbiotics, but each have their limitations, including cost and their translation to human aging biology. C. elegans is an excellent model for large-scale screening to determine the geroprotective potential of drugs or probiotics/postbiotics due to its short lifecycle, easy maintenance, low cost, and homology to humans. The purpose of this article is to review the geroprotective effects of microbiome modulators and their future scope, using C. elegans as a model. The proposed geroprotective mechanisms of these probiotics and postbiotics include delaying immune system senescence, preventing or reducing mitochondrial dysfunction, and regulating food intake (dietary restriction) and metabolism. More studies are warranted to understand the geroprotective potential of probiotics and postbiotics, as well as other microbiome modulators, like prebiotics and fermented foods, and use them to develop effective therapeutics to extend lifespan and reduce the risk of debilitating aging-related diseases.

Caenorhabditis elegans as a Screening Model for Probiotics with Properties against Metabolic Syndrome

There is a growing need to develop new approaches to prevent and treat diseases related to metabolic syndromes, including obesity or type 2 diabetes, that focus on the different factors involved in the pathogenesis of these diseases. Due to the role of gut microbiota in the regulation of glucose and insulin homeostasis, probiotics with beneficial properties have emerged as an alternative therapeutic tool to ameliorate metabolic diseases-related disturbances, including fat excess or inflammation. In the last few years, different strains of bacteria, mainly lactic acid bacteria (LAB) and species from the genus Bifidobacterium, have emerged as potential probiotics due to their anti-obesogenic and/or anti-diabetic properties. However, in vivo studies are needed to demonstrate the mechanisms involved in these probiotic features. In this context, Caenorhabditis elegans has emerged as a very powerful simple in vivo model to study the physiological and molecular effects of probiotics with potential applications regarding the different pathologies of metabolic syndrome. This review aims to summarize the main studies describing anti-obesogenic, anti-diabetic, or anti-inflammatory properties of probiotics using C. elegans as an in vivo research model, as well as providing a description of the molecular mechanisms involved in these activities.

Lacticaseibacillus rhamnosus HA-114 and Bacillus subtilis R0179 Prolong Lifespan and Mitigate Amyloid-β Toxicity in C. elegans via Distinct Mechanisms

Background

Recent advances linking gut dysbiosis with neurocognitive disorders such as Alzheimer's disease (AD) suggest that the microbiota-gut-brain axis could be targeted for AD prevention, management, or treatment.

Objective

We sought to identify probiotics that can delay Aβ-induced paralysis.

Methods

Using C. elegans expressing human amyloid-β (Aβ)1-42 in body wall muscles (GMC101), we assessed the effects of several probiotic strains on paralysis.

Results

We found that Lacticaseibacillus rhamnosus HA-114 and Bacillus subtilis R0179, but not their supernatants or heat-treated forms, delayed paralysis and prolonged lifespan without affecting the levels of amyloid-β aggregates. To uncover the mechanism involved, we explored the role of two known pathways involved in neurogenerative diseases, namely mitophagy, via deletion of the mitophagy factor PINK-1, and fatty acid desaturation, via deletion of the Δ9 desaturase FAT-5. Pink-1 deletion in GMC101 worms did not modify the life-prolonging and anti-paralysis effects of HA-114 but reduced the protective effect of R0179 against paralysis without affecting its life-prolonging effect. Upon fat5 deletion in GMC101 worms, the monounsaturated C14:1 and C16:1 FAs conserved their beneficial effect while the saturated C14:0 and C16:0 FAs did not. The beneficial effects of R0179 on both lifespan and paralysis remained unaffected by fat-5 deletion, while the beneficial effect of HA-114 on paralysis and lifespan was significantly reduced.

Conclusions

Collectively with clinical and preclinical evidence in other models, our results suggest that HA-114 or R0179 could be studied as potential therapeutical adjuncts in neurodegenerative diseases such as AD.

Bifidobacterium animalis subsp. lactis BPL1™ and Its Lipoteichoic Acid Modulate Longevity and Improve Age/Stress-Related Behaviors in Caenorhabditis elegans

Life expectancy has increased globally in recent decades, driving interest in maintaining a healthy life that includes preservation of physical and mental abilities, particularly in elderly people. The gut microbiome becomes increasingly perturbed with aging so the use of probiotics can be a strategy for maintaining a balanced gut microbiome. A previous report showed that Bifidobacterium animalis subsp. lactis BPL1™ induces through its lipoteichoic acid (LTA) fat reduction activities via the insulin/IGF-1 signaling pathway. Here, we have delved into the mechanism of action, eliminating alternative pathways as putative mechanisms. Furthermore, we have identified that BPL1™, its heat treated form (BPL1™ HT) and its LTA prolong longevity in Caenorhabditis elegans (C. elegans) in an insulin/IGF-1-dependent mechanism, and its consumption improves the oxidative stress response, gut permeability and protection against pathogenic infections. Furthermore, positive effects on C. elegans stress-related behaviors and in the Alzheimer's Disease model were found, highlighting the potential of the strain in improving the cognitive functions and proteotoxicity in the nematode. These results indicate the pivotal role of the IGF-1 pathway in the activity of the strain and pave the way for potential applications of BPL1™, BPL1™ HT and its LTA in the field of longevity and age-related markers.

Free radical-mediated extraction of polysaccharides from Gelidium amansii and their modulation on abnormal glycometabolism in Caenorhabditis elegans

An improved Fenton-microwave synergistic method was employed to extract polysaccharides from Gelidium amansii (GAPs), which were subsequently purified through alcohol precipitation, deproteinization, and gel chromatography. The effects of GAPs on oxidative stress resistance and abnormal glycometabolism were investigated using Caenorhabditis elegans. The polysaccharide yield reached 54.17 % ± 0.27 % under the following conditions: solid-liquid ratio of 1:102 g/mL, temperature of 80 °C, H2O2 concentration of 1.0 %, microwave power of 700 W, and 33 min. The purified GAPs were heteropolysaccharides primarily composed of mannose, ribose, glucuronic acid, glucose, galactose, xylose, and arabinose, with a molar ratio of 0.287:0.524:0.634:2.646:89.649:5.416:0.463. The weight-average and numerical-average molecular weights of the GAPs were determined to be 142.800 kDa and 75.255 kDa, respectively. Treatment of C. elegans with GAPs at 2.0 mg/mL resulted in a significant extension of the mean lifespan by 53.85 % compared to the negative control (p < 0.05). Furthermore, GAPs exhibited notable enhancements in the antioxidant system, including SOD by 56.90 % and CAT by 96.83 % (p < 0.05). Additionally, GAPs led to reductions in glucose-related metabolites, including glucose levels by 34.54 % and pyruvic acid levels by 149.54 % (p < 0.05). These findings demonstrate the excellent performance of GAPs in enhancing the antioxidant system and regulating abnormal glycometabolism.

Recent advances in enzymatic properties, preparation methods, and functions of glycoside hydrolase from Bifidobacterium: a review

Bifidobacterium is a major probiotic of intestinal gut flora and exerts many physiological activities, and it is widely applied in the fields of food and medicine. As an important part of Bifidobacterium, glycoside hydrolase plays a role in its physiological activity. With the continuous development and improvement of genetic engineering technology, research on this type of enzyme will play a crucial role in promoting the further development of Bifidobacterium in the field of probiotics. In this review, the preparation methods, enzymatic properties, and functions of glycoside hydrolase extracted from Bifidobacterium are described and summarized. The common method for preparing glycoside hydrolase derived from Bifidobacterium is heterologous expression in Escherichia coli BL21. The optimal pH range for these glycoside hydrolase enzymes is between 4.5 and 7.5; the optimal temperature is between 30 and 50 °C, which is close to the optimal growth condition of Bifidobacterium. Based on substrate specificity, these glycoside hydrolase could hydrolyze synthetic substrates and natural oligosaccharides, including a series of pNP artificial substrates, disaccharide, and trisaccharides, while they have little ability to hydrolyze polysaccharide substrates. This review will be expected to provide a basis for the development of Bifidobacterium as a probiotic element.

Probiotic effects of Lactococcus lactis and Leuconostoc mesenteroides on stress and longevity in Caenorhabditis elegans

The short lifespan of Caenorhabditis elegans enables the efficient investigation of probiotic interventions affecting stress and longevity involving the potential therapeutic value of Lactococcus lactis and Leuconostoc mesenteroides isolated from organic basil. The lactic acid bacteria were cultured from the produce collected from a local grocery store in Tulsa, Oklahoma, and then identified through 16S rDNA sequencing and biochemical tests. To dive deep into this analysis for potential probiotic therapy, we used fluorescent reporters that allow us to assess the differential induction of multiple stress pathways such as oxidative stress and the cytoplasmic, endoplasmic reticulum, and the mitochondrial unfolded protein response. This is combined with the classic health span measurements of survival, development, and fecundity, allowing a wide range of organismal observations of the different communities of microbes supported by probiotic supplementation with Lactococcus lactis and Leuconostoc mesenteroides. These strains were initially assessed in relation to the Escherichia coli feeding strain OP50 and the C. elegans microbiome. The supplementation showed a reduction in the median lifespan of the worms colonized within the microbiome. This was unsurprising, as negative results are common when probiotics are introduced into healthy microbiomes. To further assess the supplementation potential of these strains on an unhealthy (undifferentiated) microbiome, the typical axenic C. elegans diet, OP50, was used to simulate this single-species biome. The addition of lactic acid bacteria to OP50 led to a significant improvement in the median and overall survival in simulated biomes, indicating their potential in probiotic therapy. The study analyzed the supplemented cultures in terms of C. elegans' morphology, locomotor behavior, reproduction, and stress responses, revealing unique characteristics and stress response patterns for each group. As the microbiome's influence on the health span gains interest, the study aims to understand the microbiome relationships that result in differential stress resistance and lifespans by supplementing microbiomes with Lactococcus lactis and Leuconostoc mesenteroides isolated from organic basil in C. elegans.

Supplementation with a New Standardized Extract of Green and Black Tea Exerts Antiadipogenic Effects and Prevents Insulin Resistance in Mice with Metabolic Syndrome

Insulin resistance is one of the main characteristics of metabolic syndrome (MetS) and the main cause of the development of type II diabetes. The high prevalence of this syndrome in recent decades has made it necessary to search for preventive and therapeutic agents, ideally of natural origin, with fewer side effects than conventional pharmacological treatments. Tea is widely known for its medicinal properties, including beneficial effects on weight management and insulin resistance. The aim of this study was to analyze whether a standardized extract of green and black tea (ADM^® Complex Tea Extract (CTE)) prevents the development of insulin resistance in mice with MetS. For this purpose, C57BL6/J mice were fed for 20 weeks with a standard diet (Chow), a diet with 56% kcal from fat and sugar (HFHS) or an HFHS diet supplemented with 1.6% CTE. CTE supplementation reduced body weight gain, adiposity and circulating leptin levels. Likewise, CTE also exerted lipolytic and antiadipogenic effects in 3T3-L1 adipocyte cultures and in the C. elegans model. Regarding insulin resistance, CTE supplementation significantly increased plasma adiponectin concentrations and reduced the circulating levels of insulin and the HOMA-IR. Incubation of liver, gastrocnemius muscle and retroperitoneal adipose tissue explants with insulin increased the pAkt/Akt ratio in mice fed with Chow and HFHS + CTE but not in those fed only with HFHS. The greater activation of the PI3K/Akt pathway in response to insulin in mice supplemented with CTE was associated with a decrease in the expression of the proinflammatory markers Mcp-1, IL-6, IL-1β or Tnf-α and with an overexpression of the antioxidant enzymes Sod-1, Gpx-3, Ho-1 and Gsr in these tissues. Moreover, in skeletal muscle, mice treated with CTE showed increased mRNA levels of the aryl hydrocarbon receptor (Ahr), Arnt and Nrf2, suggesting that the CTE's insulin-sensitizing effects could be the result of the activation of this pathway. In conclusion, supplementation with the standardized extract of green and black tea CTE reduces body weight gain, exerts lipolytic and antiadipogenic effects and reduces insulin resistance in mice with MetS through its anti-inflammatory and antioxidant effects.

Akkermansia muciniphila Cell-Free Supernatant Improves Glucose and Lipid Metabolisms in Caenorhabditis elegans

To explore the mechanism by which Akkermansia muciniphila cell-free supernatant improves glucose and lipid metabolisms in Caenorhabditis elegans, the present study used different dilution concentrations of Akkermansia muciniphila cell-free supernatant as an intervention for with Caenorhabditis elegans under a high-glucose diet. The changes in lifespan, exercise ability, level of free radicals, and characteristic indexes of glucose and lipid metabolisms were studied. Furthermore, the expression of key genes of glucose and lipid metabolisms was detected by qRT-PCR. The results showed that A. muciniphila cell-free supernatant significantly improved the movement ability, prolonged the lifespan, reduced the level of ROS, and alleviated oxidative damage in Caenorhabditis elegans. A. muciniphila cell-free supernatant supported resistance to increases in glucose and triglyceride induced by a high-glucose diet and downregulated the expression of key genes of glucose metabolism, such as gsy-1, pygl-1, pfk-1.1, and pyk-1, while upregulating the expression of key genes of lipid metabolism, such as acs-2, cpt-4, sbp-1, and tph-1, as well as down-regulating the expression of the fat-7 gene to inhibit fatty acid biosynthesis. These findings indicated that A. muciniphila cell-free supernatant, as a postbiotic, has the potential to prevent obesity and improve glucose metabolism disorders and other diseases.

The effects of polyphenols against oxidative stress in Caenorhabditis elegans are determined by coexisting bacteria

Introduction

Increasing evidence supports the role of gut microbiota in many aspects of human health, including immune, metabolic and neurobehavioral traits. Several studies have focused on how different components of the diet, such as polyphenols, can modulate the composition and function of the gut microbiota leading to health benefits.

Methods

The effects on the resistance against thermally induced oxidative stress of C. elegans grown in the presence of flavonoids (quercetin or epicatechin) and fed different probiotic strains, namely Lactobacillus plantarum CLC17, Bifidobacterium longum NCIMB 8809 and Enterococcus faecium CECT 410, were explored.

Results

Feeding C. elegans with the assayed bacteria in the absence of flavonoids did not significantly affect body size and fertility of the worms neither improve their resistance against oxidative stress compared to E. coli controls. However, increased resistance to stress was found when C. elegans was cultivated in the presence of both L. plantarum and flavonoids, but not with B. longum or E. faecium. An exploratory study revealed the presence of glycosylated and sulfated metabolites together with the aglycone in worms treated with quercetin and fed any of the different assayed LAB strains. However, in the assays with epicatechin a differential metabolite, tentatively identified as 5-(4'-hydroxyphenyl)-γ-valerolactone 3'-O-glucoside, was detected in the worms fed L. plantarum but not with the other bacteria.

Conclusion

The obtained results indicated that the interactions bacteria/polyphenol play a key role in the effects produced in C. elegans regarding resistance against oxidative stress, although those effects cannot be only explained by the ability of bacteria to metabolize polyphenols, but other mechanisms should also be involved.

Lysinibacillus sphaericus mediates stress responses and attenuates arsenic toxicity in Caenorhabditis elegans

Exposure to toxic metals alters host response and that leads to disease development. Studies have revealed the effects of metals on microbial physiology, however, the role of metal resistant bacteria on host response to metals is unclear. The hypothesis that xenobiotic interactions between gut microbes and arsenic influence the host physiology and toxicity was assessed in a Caenorhabditis elegans model. The arsenic-resistant Lysinibacillus sphaericus B1CDA was fed to C. elegans to determine the host responses to arsenic in comparison to Escherichia coli OP50 food. L. sphaericus diet extended C. elegans lifespan compared to E. coli diet, with an increased expression of genes involved in lifespan, stress response and immunity (hif-1, hsp-16.2, mtl-2, abf-2, clec-60), as well as reduced fat accumulation. Arsenic-exposed worms fed L. sphaericus also had a longer lifespan than those fed E. coli and had an increased expression of genes involved in cytoprotection, stress resistance (mtl-1, mtl-2) and oxidative stress response (cyp-35A2, isp-1, ctl-2, sod-1), together with a decreased accumulation of reactive oxygen species (ROS). In comparison with E. coli, L. sphaericus B1CDA diet increased C. elegans fitness while detoxifying arsenic induced ROS and extending lifespan.

A Lactobacilli diet that confers MRSA resistance causes amino acid depletion and increased antioxidant levels in the C. elegans host

Probiotic bacteria are increasingly popular as dietary supplements and have the potential as alternatives to traditional antibiotics. We have recently shown that pretreatment with Lactobacillus spp. Lb21 increases the life span of C. elegans and results in resistance toward pathogenic methicillin-resistant Staphylococcus aureus (MRSA). The Lb21-mediated MRSA resistance is dependent on the DBL-1 ligand of the TGF-β signaling pathway. However, the underlying changes at the metabolite level are not understood which limits the application of probiotic bacteria as timely alternatives to traditional antibiotics. In this study, we have performed untargeted nuclear magnetic resonance-based metabolic profiling. We report the metabolomes of Lactobacillus spp. Lb21 and control E. coli OP50 bacteria as well as the nematode-host metabolomes after feeding with these diets. We identify 48 metabolites in the bacteria samples and 51 metabolites in the nematode samples and 63 across all samples. Compared to the control diet, the Lactobacilli pretreatment significantly alters the metabolic profile of the worms. Through sparse Partial Least Squares discriminant analyses, we identify the 20 most important metabolites distinguishing probiotics from the regular OP50 food and worms fed the two different bacterial diets, respectively. Among the changed metabolites, we find lower levels of essential amino acids as well as increased levels of the antioxidants, ascorbate, and glutathione. Since the probiotic diet offers significant protection against MRSA, these metabolites could provide novel ways of combatting MRSA infections.

Effects of Coix Seed Extract, Bifidobacterium BPL1, and Their Combination on the Glycolipid Metabolism in Obese Mice

Coix seed extract (CSE) and probiotics have been reported to regulate glycolipid metabolism via different modes of action. We tested the effects of CSE, Bifidobacterium BPL1, and their combination to determine their effects on glycolipid metabolism in obese mice. Male C57BL/6J mice were fed a high-fat diet for 8 weeks to establish an obesity model. Obese mice were selected and divided into four groups: the model control group and three intervention groups. After 10 weeks of continuous gavage intervention, the mice in the intervention groups exhibited lower body weight (lower about 2.31 g, vs. HFD mice 42.23 g) and epididymal (lower about 0.37 g, vs. HFD mice 2.5 g) and perirenal fat content (lower about 0.47 g, vs. HFD mice 0.884 g); decreased fasting blood glucose, total cholesterol, triglycerides, and VLDL; and increased HLDL, respiratory exchange ratio, energy expenditure, and amount of exercise performed. CSE, BPL1 and their combination can effectively control the weight gain in obese mice, reduce fat content, and regulate blood lipids and abnormal blood sugar. These results may be related to reduce the chronic inflammatory states, improve energy metabolism, exercise, relieve insulin sensitivity, and reduce lipid synthesis via the intervention of CSE, BPL1 and their combination. Compared with the single use of CSE alone, the combination of CSE + BPL1 can better exert the regulation function of intestinal flora, and change in the abundance of bacteria that could improve the level of inflammatory factors, such as increasing Bifidobacterium, reducing Lactococcus. Compared with the use of BPL1 alone, the combination of CSE and BPL1 can better regulate pancreatic islet and improve blood sugar. CSE may act directly on body tissues to exert anti-inflammatory effects. BPL1 and CSE + BPL1 may improve the structure and function of the intestinal flora, and reduce tissue inflammation.

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

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

Lactobacillus brevis MTCC 1750 enhances oxidative stress resistance and lifespan extension with improved physiological and functional capacity in Caenorhabditis elegans via the DAF-16 pathway

Redox imbalance plays a crucial role in the development of age-related diseases, and resistance to oxidative stress is crucial for optimum longevity and healthy aging. Using the wild-type, mutant and transgenic strains, this study explored the antioxidative potential and lifespan extension benefits of different Lactobacillus strains in Caenorhabditis elegans (C. elegans). We observed that Lactobacillus brevis MTCC 1750 could enhance the resistance of C. elegans against juglone induced oxidative stress by reducing its intracellular reactive oxygen species (ROS) accumulation. Also, live L. brevis MTCC 1750 could prolong the worm's lifespan. These effects are dependent on transcription factor DAF-16 evident with significant upregulation of its target gene sod-3. This also explained the significant improvements in different age-associated changes in physiological and mechanical parameters of the worm by L. brevis MTCC 1750. Further investigations revealed that DAF-16 activation and, its enhanced translocation in the nucleus is independent of DAF-2 or JNK pathway. These findings highlighted L. brevis MTCC 1750 as a potent anti-oxidant source for complementing current antioxidant therapeutic strategies. Nonetheless, the findings showed how different signaling events are regulated based on an organism's diet component, and their consequences on the aging process in multiple species.

Evaluation of Antioxidative and Neuroprotective Activities of Total Flavonoids From Sea Buckthorn (Hippophae rhamnoides L.)

The aim of this study was to investigate the antioxidative and neuroprotective activities of total flavonoids from sea buckthorn (Hippophae rhamnoides L.) (TFH). Results indicated that TFH possessed DPPH radicals, hydroxyl radicals and superoxide anions scavenging activities. The neuroprotective potential was assessed with acetylcholinesterase (AChE) and monoamine oxidase A (MAO-A). The inhibition rates of AChE and MAO-A by 50 μg/ml TFH were 75.85 and 51.22%, respectively. The in vivo antioxidative and neuroprotective potential of TFH were explored in Caenorhabditis elegans. In the longevity assay, TFH (50 μg/ml) significantly increased the lifespan of wild-type C. elegans (29.40%). In the hydrogen peroxide-induced oxidative stress challenge, the antioxidant capacity of TFH-treated wild-type C. elegans was significantly enhanced. The C. elegans mutant strain CL4176 was used to study the neuroprotective effect of TFH in vivo. Results showed that TFH significantly delayed paralysis in C. elegans CL4176. Our study suggested total flavonoids from sea buckthorn (Hippophae rhamnoides L.) had the potential as an antioxidative and neuroprotective agent to extend aging and treat neurodegenerative diseases.

Identification of γ-Glutamyl-Selenomethionine as the Principal Selenium Metabolite in a Selenium-Enriched Probiotic, Bifidobacterium longum, by Two-Dimensional HPLC-ICP MS and HPLC-ESI Orbitrap MS

Selenium (Se)-enriched probiotics are potential sources of organic Se in the human diet, but their application in food is debated because most selenized probiotics and their metabolites are not well-characterized. We analyzed a Se-enriched probiotic, Bifidobacterium longum DD98, to unveil its Se metabolite profiles by two-dimensional high-performance liquid chromatography inductively coupled plasma mass spectrometry (HPLC-ICP MS) and HPLC-electrospray ionization Orbitrap MS. A major Se metabolite was identified as gamma-glutamyl-selenomethionine (γ-Glu-SeMet), which accounted for 42.5 ± 3.4% of water-soluble Se. Most of the remaining Se was present as SeMet (35.2 ± 0.6%) in a free or protein-bound form. In addition, 11 minor Se metabolites were identified, eight of which had not been reported before in probiotics. Six of the identified compounds contained γ-Glu-SeMet as the core structure, constituting a γ-Glu-SeMet family. This study demonstrates the presence of γ-Glu-SeMet in a probiotic, showing a different selenite metabolite pathway from that of Se-enriched yeast, and it offers an alternative and potentially attractive source of organic Se for food and feed supplementation.

Pediococcus acidilactici Promotes the Longevity of C. elegans by Regulating the Insulin/IGF-1 and JNK/MAPK Signaling, Fat Accumulation and Chloride Ion

Probiotics are known to contribute to the anti-oxidation, immunoregulation, and aging delay. Here, we investigated the extension of lifespan by fermented pickles-origin Pediococcus acidilactici (PA) in Caenorhabditis elegans (C. elegans), and found that PA promoted a significantly extended longevity of wild-type C. elegans. The further results revealed that PA regulated the longevity via promoting the insulin/IGF-1 signaling, JNK/MAPK signaling but not TOR signaling in C. elegans, and that PA reduced the reactive oxygen species (ROS) levels and modulated expression of genes involved in fatty acids uptake and lipolysis, thus reducing the fat accumulation in C. elegans. Moreover, this study identified the nrfl-1 as the key regulator of the PA-mediated longevity, and the nrfl-1/daf-18 signaling might be activated. Further, we highlighted the roles of one chloride ion exchanger gene sulp-6 in the survival of C. elegans and other two chloride ion channel genes clh-1 and clh-4 in the prolonged lifespan by PA-feeding through the modulating expression of genes involved in inflammation. Therefore, these findings reveal the detailed and novel molecular mechanisms on the longevity of C. elegans promoted by PA.

Pediococcus acidilactici CECT9879 (pA1c) Counteracts the Effect of a High-Glucose Exposure in C. elegans by Affecting the Insulin Signaling Pathway (IIS)

The increasing prevalence of metabolic syndrome-related diseases, including type-2 diabetes and obesity, makes it urgent to develop new alternative therapies, such as probiotics. In this study, we have used Caenorhabditis elegans under a high-glucose condition as a model to examine the potential probiotic activities of Pediococcusacidilactici CECT9879 (pA1c). The supplementation with pA1c reduced C. elegans fat accumulation in a nematode growth medium (NGM) and in a high-glucose (10 mM) NGM medium. Moreover, treatment with pA1c counteracted the effect of the high glucose by reducing reactive oxygen species by 20%, retarding the aging process and extending the nematode median survival (>2 days in comparison with untreated control worms). Gene expression analyses demonstrated that the probiotic metabolic syndrome-alleviating activities were mediated by modulation of the insulin/IGF-1 signaling pathway (IIS) through the reversion of the glucose-nuclear-localization of daf-16 and the overexpression of ins-6 and daf-16 mediators, increased expression of fatty acid (FA) peroxisomal β-oxidation genes, and downregulation of FA biosynthesis key genes. Taken together, our data suggest that pA1c could be considered a potential probiotic strain for the prevention of the metabolic syndrome-related disturbances and highlight the use of C. elegans as an appropriate in vivo model for the study of the mechanisms underlying these diseases.

Anti-Obesity Efficacy of Pediococcus acidilactici MNL5 in Canorhabditis elegans Gut Model

In the present study, thirty two lactic acid bacteria (LAB) were isolated from fermented Indian herbal medicine. In comparison to other strains, MNL5 had stronger bile salt hydrolase (BSH) and cholesterol-lowering properties. Furthermore, it can withstand the extreme conditions found in the GI tract, due to, e.g., pepsin, bile salts, pancreatin, and acids. Pediococcus acidilactici MNL5 was identified as a probiotic candidate after sequencing the 16S rRNA gene. The antibacterial activity of P. acidilactici MNL5 cell-free supernatants (CFS) against Escherichia coli, Staphylococcus aureus, Helicobacter pylori, Bacillus cereus, and Candida albicans was moderate. A Caenorhabditis elegans experiment was also performed to assess the effectiveness of P. acidilactici MNL5 supplementation to increase life span compared to E. coli supplementation (DAF-2 and LIU1 models) (p < 0.05). An immense reduction of the lipid droplets of C. elegans was identified through a fluorescent microscope. The drastic alteration of the expression of fat genes is related to obesity phenotypes. Hence, several paths are evolutionary for C. elegans; the results of our work highlight the nematode as an important model for obesity.

Recent Development of Probiotic Bifidobacteria for Treating Human Diseases

Bifidobacterium is a non-spore-forming, Gram-positive, anaerobic probiotic actinobacterium and commonly found in the gut of infants and the uterine region of pregnant mothers. Like all probiotics, Bifidobacteria confer health benefits on the host when administered in adequate amounts, showing multifaceted probiotic effects. Examples include B. bifidum, B. breve, and B. longum, common Bifidobacterium strains employed to prevent and treat gastrointestinal disorders, including intestinal infections and cancers. Herein, we review the latest development in probiotic Bifidobacteria research, including studies on the therapeutic impact of Bifidobacterial species on human health and recent efforts in engineering Bifidobacterium. This review article would provide readers with a wholesome understanding of Bifidobacteria and its potentials to improve human health.

The gut microbiota and its products: Establishing causal relationships with obesity related outcomes

Gut microorganisms not only participate in the metabolism of carbohydrate, lipids, protein, and polypeptides in the intestine but also directly affect the metabolic phenotypes of the host. Although many studies have described the apparent effects of gut microbiota on human health, the development of metagenomics and culturomics in the past decade has generated a large amount of evidence suggesting a causal relationship between gut microbiota and obesity. The interaction between the gut microbiota and host is realized by microbial metabolites with multiple biological functions. We concentrated here on several representative beneficial species connected with obesity as well as the mechanisms, with particular emphasis on microbiota-dependent metabolites. Finally, we consider the potential clinical significance of these relationships to fuel the conception and realization of novel therapeutic and preventive strategies.

Probiotics Interactions and the Modulation of Major Signalling Pathways in Host Model Organism Caenorhabditis elegans

Microorganisms live in the human digestive system and the gut microbiome constitutes part of our prime determining component for healthy aging and wellness. Gut microbiota has broad influences on its host, beginning from the digestion of food and nutrients absorption to protective roles against invading pathogens and host immune system regulation. Dysbiosis of the gut microbial composition has been linked to numerous diseases and there is a need to have a better grasp on what makes a 'good' gut microbiome. Caenorhabditis elegans (C. elegans) model organism is considered as a well-suited in-vivo model system and, is at the frontline of probiotic research because of its well-defined characteristics and prolific nature. Most importantly, C. elegans feeds on bacteria, which speeds up manipulations and investigations in probiotics research tremendously. With its unique salient features of short lifespan, and ease of propagation, different unknown probiotics biological roles can be measured at an organism level with precision in the form of worm's stress responses, survivability, and lifespan. In this review, new insights on the different mechanisms underlying the establishment of probiotics regulations of conserved signalling pathways such as p38 MAPK/SKN-1, DAF-2/DAF-16, and JNK-1/DAF-16 is highlighted based on information obtained from C. elegans studies. Along with the current state of knowledge and the uniqueness of C. elegans as a model organism, explorations of its future contribution and scope in synthetic biology and probiotics engineering strains are also addressed. This is expected to strengthen our understanding of probiotics roles and to facilitate novel discovery and applications, for specific therapeutics against age-related disorders and various pathophysiological conditions.

Antioxidant and reducing lipid accumulation effects of rutin in Caenorhabditis elegans

In this study, the effect of rutin on fatty acid metabolism and antioxidant activity were evaluated. We found that the antioxidant capacity of rutin-treated Caenorhabditis elegans was enhanced but the triglyceride content was significantly reduced. The reduction of fat accumulation by rutin was also confirmed by Oil Red O staining. RNA-seq analysis indicated that rutin significantly regulated the expression of seven genes related to lipid metabolism in C. elegans. Among the seven genes, acox-1.3, stdh-3, and fat-7 were associated with fatty acid metabolism. Rutin significantly reduced fat accumulation in both fat-6 and fat-7 mutant strains but did not affect the fat storage of fat-6/fat-7 double mutant, which indicated that the impact of rutin on fat storage depended on fat-6 and fat-7. These findings indicated that rutin reduced fat storage depending on the regulation of lipid metabolism-related genes expression and thereby regulating the biosynthesis of the corresponding unsaturated fatty acid.

Weissella confusa CGMCC 19,308 Strain Protects Against Oxidative Stress, Increases Lifespan, and Bacterial Disease Resistance in Caenorhabditis elegans

The aim of this study was to investigate the antioxidant activity of Weissella confusa CGMCC 19,308 and its influence on longevity and host defense against Salmonella Typhimurium of Caenorhabditis elegans. The CFCS (cell-free culture supernatant) of W. confusa CGMCC 19,308 possessed DPPH radicals, hydroxyl radicals, and superoxide anion scavenging activity. The lifespan of the C. elegans fed W. confusa CGMCC 19,308 was significantly (p < 0.001) longer than that of worms fed Escherichia coli OP50. Moreover, worms fed W. confusa CGMCC 19,308 were more resistant to oxidative stress induced by hydrogen peroxide and S. Typhimurium infection. RNA-seq analysis showed that the most significantly differentially expressed genes (DEGs) in C. elegans fed with W. confusa CGMCC 19,308 were mainly col genes (col-43, col-2, col-40, col-155, col-37), glutathione-S-transferase (GST)-related genes (gst-44, gst-9, gst-17, gst-18, gstk-2), cnc-9 (immune-related gene), and sod-5 (superoxide dismutase). These results indicated that cuticle collagen synthesis, immunity, and antioxidant defense (AOD) system of C. elegans were affected after being fed with W. confusa CGMCC 19,308 instead of E. coli OP50. Our study suggested W. confusa CGMCC 19,308 had the antioxidant activity and could prolong lifespan and enhance the host defense against S. Typhimurium of C. elegans. This study provided new evidences for the W. confusa CGMCC 19,308 as a potential probiotic candidate for anti-aging and anti-bacterial infection.

Heat-Treated Bifidobacterium longum CECT-7347: A Whole-Cell Postbiotic with Antioxidant, Anti-Inflammatory, and Gut-Barrier Protection Properties

Non-viable preparations of probiotics, as whole-cell postbiotics, attract increasing interest because of their intrinsic technological stability, and their functional properties, such as immune system modulation, gut barrier maintenance, and protection against pathogens. However, reports on Bifidobacteria-derived postbiotics remain scarce. This study aims to demonstrate the functional properties of a heat-treated (HT), non-viable, Bifidobacterium longum strain, CECT-7347, a strain previously selected for its anti-inflammatory phenotype and ability to improve biomarkers of intestinal integrity in clinical trials. The study used the nematode Caenorhabditis elegans and HT-29 cell cultures as eukaryotic model systems. Our results show that HT-CECT-7347 preserves the capacity to protect against oxidative stress damage, while it also reduces acute inflammatory response and gut-barrier disruption, and inhibits bacterial colonization, by activating pathways related to innate immune function. These findings highlight the interest of the ingredient as a novel postbiotic and pave the way to broaden the range of HT-CECT-7347 applications in gut health.

Probiotic Properties of Alcaligenes faecalis Isolated from Argyrosomus regius in Experimental Peritonitis (Rat Model)

A strain of Alcaligenes faecalis A12C (A. faecalis A12C) isolated from Argyrosomus regius is a probiotic in fish. Previous experiments showed that A. faecalis A12C had inhibitory effects on the growth of multidrug-resistant bacteria. We aimed to confirm whether A. faecalis A12C is safe and has adequate intestinal colonization in experimental rats, and evaluate its efficacy in an animal model of peritonitis. We used 30 male rats, randomly divided into 6 groups (n = 5): three groups (HA7, HA15, HA30) received A. faecalis A12C in drinking water (6 × 10⁸ CFU/mL) for 7 days, and three control groups received drinking water only. All groups were evaluated at 7, 15, and 30 days. Survival after A. faecalis A12C administration was 100% in all groups. Mild eosinophilia (1.5%, p < 0.01) and increased aspartate aminotransferase (86 IU/L, p < 0.05) were observed in HA7, followed by progressive normalization. No histological signs of organ injury were found. We observed significant E. coli decline in faeces, parallel to an increase in A. faecalis A12C at 7 days. E. coli had a tendency to recover initial values, while A. faecalis A12C disappeared from the intestinal microbiota at 30 days. To evaluate its efficacy against peritonitis, we studied two additional groups of animals: IA group pretreated with A. faecalis A12C before E. coli intra-abdominal inoculation, and IC group inoculated with no A. faecalis A12C. We found an increase in C-reactive protein, alanine aminotransferase, urea, and eosinophils in IC animals when compared with IA. Peritonitis was more evident in IC than in IA animals. Our findings suggest that A. faecalis A12C altered clinically relevant parameters in sepsis and was associated with a lesser spread of infection.

Lipoteichoic acid from Bifidobacterium animalis subsp. lactis BPL1: a novel postbiotic that reduces fat deposition via IGF-1 pathway

Obesity and its related metabolic disorders, such as diabetes and cardiovascular disease, are major risk factors for morbidity and mortality in the world population. In this context, supplementation with the probiotic strain Bifidobacterium animalis subsp. lactis BPL1 (CECT8145) has been shown to ameliorate obesity biomarkers. Analyzing the basis of this observation and using the pre-clinical model Caenorhabditis elegans, we have found that lipoteichoic acid (LTA) of BPL1 is responsible for its fat-reducing properties and that this attribute is preserved under hyperglycaemic conditions. This fat-reducing capacity of both BPL1 and LTA-BPL1 is abolished under glucose restriction, as a result of changes in LTA chemical composition. Moreover, we have demonstrated that LTA exerts this function through the IGF-1 pathway, as does BPL1 strain. These results open the possibility of using LTA as a novel postbiotic, whose beneficial properties can be applied therapeutically and/or preventively in metabolic syndrome and diabetes-related disorders.

Effects of Bifidobacterium animalis Subsp. lactis (BPL1) Supplementation in Children and Adolescents with Prader-Willi Syndrome: A Randomized Crossover Trial

Prader-Willi syndrome (PWS) is a rare genetic disorder characterized by a wide range of clinical manifestations, including obesity, hyperphagia, and behavioral problems. Bifidobacterium animalis subsp. lactis strain BPL1 has been shown to improve central adiposity in adults with simple obesity. To evaluate BPL1's effects in children with PWS, we performed a randomized crossover trial among 39 patients (mean age 10.4 years). Participants were randomized to placebo-BPL1 (n = 19) or BPL1-placebo (n = 20) sequences and underwent a 12-week period with placebo/BPL1 treatments, a 12-week washout period, and a 12-week period with the crossover treatment. Thirty-five subjects completed the study. The main outcome was changes in adiposity, measured by dual-energy X-ray absorptiometry. Secondary outcomes included lipid and glucose metabolism, hyperphagia, and mental health symptoms. Generalized linear modeling was applied to assess differences between treatments. While BPL1 did not modify total fat mass compared to placebo, BPL1 decreased abdominal adiposity in a subgroup of patients older than 4.5 years (n = 28). BPL1 improved fasting insulin concentration and insulin sensitivity. Furthermore, we observed modest improvements in some mental health symptoms. A follow-up trial with a longer treatment period is warranted to determine whether BPL1 supplementation can provide a long-term therapeutic approach for children with PWS (ClinicalTrials.gov NCT03548480).

Current and future experimental approaches in the study of grape and wine polyphenols interacting gut microbiota

Interactions between polyphenols and gut microbiota are indeed a major issue of current interest in food science research. Knowledge in this subject is progressing as the experimental procedures and analysis techniques do. The aim of this article is to critically review the more leading-edge approaches that have been applied so far in the study of the interactions between grape/wine polyphenols and gut microbiota. This is the case of in vitro dynamic gastrointestinal simulation models that try to mitigate the limitations of simple static models (batch culture fermentations). More complex approaches include the experimentation with animals (mice, rats, pigs, lambs and chicks) and nutritional intervention studies in humans. Main advantages and limitations as well as the most relevant findings achieved by each approach in the study of how grape/wine polyphenols can modulate the composition and/or functionality of gut microbiota, are detailed. Also, common findings obtained by the three approaches (in vitro, animal models and human nutritional interventions) such as the fact that the Firmicutes/Bacteroidetes ratio tends to decrease after the feed/intake/consumption of grape/wine polyphenols are highlighted. Additionally, a nematode (Caenorhabditis elegans) model, previously used for investigating the mechanisms of processes such as aging, neurodegeneration, oxidative stress and inflammation, is presented as an emerging approach for the study of polyphenols interacting gut microbiota. © 2020 Society of Chemical Industry.

Effects of Probiotic Yogurt on Serum Omentin-1, Adropin, and Nesfatin-1 Concentrations in Overweight and Obese Participants Under Low-Calorie Diet

Data on the effects of probiotics on adipokines such as omentin-1, nesfatin-1, and adropin are limited. The aim of this study was to evaluate the effects of probiotic yogurt along with a low-calorie diet (LCD) on serum omentin-1, adropin, and nesfatin-1 concentrations in obese and overweight individuals. Sixty obese or overweight individuals aged 20-50 years old were involved in this randomized double-blind placebo-controlled clinical trial. Participants were randomly allocated into two groups to consume either probiotic yogurt containing Lactobacillus acidophilus La5, Bifidobacterium BB12, and Lactobacillus casei DN001 (10⁸ CFU/g each) (n = 30) or regular yogurt (n = 30) along with a LCD in both groups for 8 weeks. Fasting blood samples were taken at baseline and after the 8-week intervention to determine related variables. A significant decrease in body fat percentage was observed in the probiotic group compared with the regular group after 8 weeks (- 1.51 ± 069 vs - 0.88 ± 0.68%, P = 0.002). After the 8-week intervention, a significant difference in serum adropin concentration (6.04 ± 24.46 vs - 8.16 ± 24.66 pg/ml, P = 0.03 and serum omentin-1 concentration (0.09 ± 1.51 vs - 1.5 ± 1.8 ng/ml, P = 0.003) was observed between two groups. We did not observe any significant changes in nesfatin-1 and other anthropometric measures. Overall, probiotic yogurt for 8 weeks among overweight or obese individuals along with LCD had beneficial effects on body fat percentage, serum omentin-1, and adropin concentration, but it did not have any effect on nesfatin-1 level.

An Infant Milk Formula Supplemented with Heat-Treated Probiotic Bifidobacterium animalis subsp. lactis CECT 8145, Reduces Fat Deposition in C. elegans and Augments Acetate and Lactate in a Fermented Infant Slurry

Pediatric obesity has a growing health and socio-economical impact due to cardiovascular and metabolic complications in adult life. Some recent studies suggest that live or heat-treated probiotics have beneficial effects in preventing fat deposition and obesity in preclinical and clinical sets. Here, we have explored the effects of heat-treated probiotic Bifidobacterium animalis subsp. lactis CECT 8145 (HT-BPL1), added as a supplement on an infant milk formula (HT-BPL1-IN), on Caenorhabditis elegans fat deposition and short-chain fatty acids (SCFAs) and lactate, using fermented baby fecal slurries. We have found that HT-BPL1-IN significantly reduced fat deposition in C. elegans, at the time it drastically augmented the generation of some SCFAs, particulary acetate and organic acid lactate. Data suggest that heat-treated BPL1 maintains its functional activities when added to an infant powder milk formula.

Caenorhabditis elegans: a model to understand host-microbe interactions

Host-microbe interactions within the gut are fundamental to all higher organisms. Caenorhabditis elegans has been in use as a surrogate model to understand the conserved mechanisms in host-microbe interactions. Morphological and functional similarities of C. elegans gut with the human have allowed the mechanistic investigation of gut microbes and their effects on metabolism, development, reproduction, behavior, pathogenesis, immune responses and lifespan. Recent reports suggest their suitability for functional investigations of human gut bacteria, such as gut microbiota of healthy and diseased individuals. Our knowledge on the gut microbial diversity of C. elegans in their natural environment and the effect of host genetics on their core gut microbiota is important. Caenorhabditis elegans, as a model, is continuously bridging the gap in our understanding the role of genetics, environment, and dietary factors on physiology of the host.

Bifidobacterium animalis subsp. lactis A6 Alleviates Obesity Associated with Promoting Mitochondrial Biogenesis and Function of Adipose Tissue in Mice

Probiotics are widely known for their health benefits. Mitochondrial dysfunction is related to obesity. The aim of this study was to illuminate whether Bifidobacterium animalis subsp. lactis A6 (BAA6) could improve obesity due to increased mitochondrial biogenesis and function of adipose tissues. Four-week-old male C57BL/6 mice were fed with a high-fat diet (HFD) for 17 weeks. For the final eight weeks, the HFD group was divided into three groups including HFD, HFD with BAA6 (HFD + BAA6 group), and HFD with Akkermansia muciniphila (AKK) (HFD + AKK group as positive control). The composition of the microbiota, serum lipopolysaccharides (LPS), and mitochondrial biosynthesis and function of epididymal adipose tissues were measured. Compared with the HFD group, body weight, relative fat weight, the relative abundance of Oscillibacter and Bilophila, and serum LPS were significantly decreased in the HFD + BAA6 and HFD + AKK groups (p < 0.05). Furthermore, the addition of BAA6 and AKK increased the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) (by 21.53- and 18.51-fold), estrogen-related receptor α (ERRα) (by 2.83- and 1.24-fold), and uncoupling protein-1 (UCP-1) (by 1.51- and 0.60-fold) in epididymal adipose tissues. Our results suggest that BAA6 could improve obesity associated with promoting mitochondrial biogenesis and function of adipose tissues in mice.

Caenorhabditis Elegans and Probiotics Interactions from a Prolongevity Perspective

Probiotics exert beneficial effects on host health through different mechanisms of action, such as production of antimicrobial substances, competition with pathogens, enhancement of host mucosal barrier integrity and immunomodulation. In the context of ageing, which is characterized by several physiological alterations leading to a low grade inflammatory status called inflammageing, evidences suggest a potential prolongevity role of probiotics. Unraveling the mechanisms underlying anti-ageing effects requires the use of simple model systems. To this respect, the nematode Caenorhabditis elegans represents a suitable model organism for the study of both host-microbe interactions and for ageing studies, because of conserved signaling pathways and host defense mechanisms involved in the regulation of its lifespan. Therefore, this review analyses the impact of probiotics on C. elegans age-related parameters, with particular emphasis on oxidative stress, immunity, inflammation and protection from pathogen infections. The picture emerging from our analysis highlights that several probiotic strains are able to exert anti-ageing effects in nematodes by acting on common molecular pathways, such as insulin/insulin-like growth factor-1 (IIS) and p38 mitogen-activated protein kinase (p38 MAPK). In this perspective, C. elegans appears to be advantageous for shedding light on key mechanisms involved in host prolongevity in response to probiotics supplementation.

Effects of daily consumption of the probiotic Bifidobacterium animalis subsp. lactis CECT 8145 on anthropometric adiposity biomarkers in abdominally obese subjects: a randomized controlled trial

BACKGROUND

The effects of probiotic Bifidobacterium animalis subsp. lactis CECT 8145 (Ba8145) and those of its heat-killed form (h-k Ba8145) on human anthropometric adiposity biomarkers are unknown.

OBJECTIVE

To assess the effect of Ba8145 and h-k Ba8145 ingestion on anthropometric adiposity biomarkers.

DESIGN

Randomized, parallel, double-blind, placebo-controlled trial with abdominally obese individuals. Participants (n = 135) consumed 1 capsule/day containing 1010 colony forming unit (CFU) of Ba8145, 1010 CFU of h-k Ba8145, or placebo (maltodextrin) for 3 months.

RESULTS

Ba8145 ingestion decreased waist circumference, waist circumference/height ratio, and Conicity index (P < 0.05) versus its baseline. Changes versus the placebo group reached significance (P < 0.05) after the h-k Ba8145 treatment. Ba8145 decreased the body mass index compared with baseline and placebo group (P < 0.05). The decrease in visceral fat area after Ba8145 treatments reached significance (P < 0.05) only after h-k Ba8145. When analyses by gender were performed, significance remained only for women. Diastolic blood pressure and HOMA index decreased (P < 0.05) after h-k Ba8145. Gut microbiome analyses showed an increase in Akkermansia spp. after Ba8145 treatment, particularly in the live form, which was inversely related to weight (P = 0.003).

CONCLUSIONS

In abdominally obese individuals, consumption of Ba8145, both as viable and mainly as heat-killed cells, improves anthropometric adiposity biomarkers, particularly in women. An increase in the gut Akkermansia genus appears as a possible mechanism involved. Our results support Ba8145 probiotic as a complementary strategy in obesity management.

Effect of Oral Administration of a Mixture of Probiotic Strains on SCORAD Index and Use of Topical Steroids in Young Patients With Moderate Atopic Dermatitis: A Randomized Clinical Trial

Importance

Oral intake of new probiotic formulations may improve the course of atopic dermatitis (AD) in a young population.

Objective

To determine whether a mixture of oral probiotics is safe and effective in the treatment of AD symptoms and to evaluate its influence on the use of topical steroids in a young population.

Design, Setting, and Participants

A 12-week randomized, double-blind, placebo-controlled intervention trial, from March to June 2016, at the outpatient hospital Centro Dermatológico Estético de Alicante, Alicante, Spain. Observers were blinded to patient groupings. Participants were children aged 4 to 17 years with moderate atopic dermatitis. The groups were stratified and block randomized according to sex, age, and age of onset. Patients were ineligible if they had used systemic immunosuppressive drugs in the previous 3 months or antibiotics in the previous 2 weeks or had a concomitant diagnosis of intestinal bowel disease or signs of bacterial infection.

Interventions

Twelve weeks with a daily capsule containing freeze-dried powder with 109 total colony-forming units of the probiotic strains Bifidobacterium lactis CECT 8145, B longum CECT 7347, and Lactobacillus casei CECT 9104 and maltodextrin as a carrier, or placebo (maltodextrin-only capsules).

Main Outcomes and Measures

SCORAD index score and days of topical steroid use were analyzed.

Results

Fifty children (26 [50%] female; mean [SD] age, 9.2 [3.7] years) participated. After 12 weeks of follow-up, the mean reduction in the SCORAD index in the probiotic group was 19.2 points greater than in the control group (mean difference, -19.2; 95% CI, -15.0 to -23.4). In relative terms, we observed a change of -83% (95% CI, -95% to -70%) in the probiotic group and -24% (95% CI, -36% to -11%) in the placebo group (P < .001). We found a significant reduction in the use of topical steroids to treat flares in the probiotic arm (161 of 2084 patient-days [7.7%]) compared with the control arm (220 of 2032 patient-days [10.8%]; odds ratio, 0.63; 95% CI, 0.51 to 0.78).

Conclusions and Relevance

The mixture of probiotics was effective in reducing SCORAD index and reducing the use of topical steroids in patients with moderate AD.

Trial Registration

clinicaltrials.gov Identifier: NCT02585986.

Bioprospecting the Solar Panel Microbiome: High-Throughput Screening for Antioxidant Bacteria in a Caenorhabditis elegans Model

Microbial communities that are exposed to sunlight typically share a series of adaptations to deal with the radiation they are exposed to, including efficient DNA repair systems, pigment production and protection against oxidative stress, which makes these environments good candidates for the search of novel antioxidant microorganisms. In this research project, we isolated potential antioxidant pigmented bacteria from a dry and highly-irradiated extreme environment: solar panels. High-throughput in vivo assays using Caenorhabditis elegans as an experimental model demonstrated the high antioxidant and ultraviolet-protection properties of these bacterial isolates that proved to be rich in carotenoids. Our results suggest that solar panels harbor a microbial community that includes strains with potential applications as antioxidants.

Dissecting the Evolutionary Development of the Species Bifidobacterium animalis through Comparative Genomics Analyses

Bifidobacteria are members of the gut microbiota of animals, including mammals, birds, and social insects. In this study, we analyzed and determined the pangenome of Bifidobacterium animalis species, encompassing B. animalis subsp. animalis and the B. animalis subsp. lactis taxon, which is one of the most intensely exploited probiotic bifidobacterial species. In order to reveal differences within the B. animalis species, detailed comparative genomics and phylogenomics analyses were performed, indicating that these two subspecies recently arose through divergent evolutionary events. A subspecies-specific core genome was identified for both B. animalis subspecies, revealing the existence of subspecies-defining genes involved in carbohydrate metabolism. Notably, these in silico analyses coupled with carbohydrate profiling assays suggest genetic adaptations toward a distinct glycan milieu for each member of the B. animalis subspecies, resulting in a divergent evolutionary development of the two subspecies.IMPORTANCE The majority of characterized B. animalis strains have been isolated from human fecal samples. In order to explore genome variability within this species, we isolated 15 novel strains from the gastrointestinal tracts of different animals, including mammals and birds. The present study allowed us to reconstruct the pangenome of this taxon, including the genome contents of 56 B. animalis strains. Through careful assessment of subspecies-specific core genes of the B. animalis subsp. animalis/lactis taxon, we identified genes encoding enzymes involved in carbohydrate transport and metabolism, while unveiling specific gene acquisition and loss events that caused the evolutionary emergence of these two subspecies.

β-Cryptoxanthin Reduces Body Fat and Increases Oxidative Stress Response in Caenorhabditis elegans Model

β-Cryptoxanthin (BCX) is a major dietary pro-vitamin A carotenoid, found mainly in fruits and vegetables. Several studies showed the beneficial effects of BCX on different aspects of human health. In spite of the evidence, the molecular mechanisms of action of BCX need to be further investigated. The Caenorhabditis elegans model was used to analyze in vivo the activity of BCX on fat reduction and protection to oxidative stress. Dose-response assays provided evidence of the efficacy of BCX at very low dose (0.025 µg/mL) (p < 0.001) on these processes. Moreover, a comparative analysis with other carotenoids, such as lycopene and β-carotene, showed a stronger effect of BCX. Furthermore, a transcriptomic analysis of wild-type nematodes supplemented with BCX revealed upregulation of the energy metabolism, response to stress, and protein homeostasis as the main metabolic targets of this xanthophyll. Collectively, this study provides new in vivo evidence of the potential therapeutic use of BCX in the prevention of diseases related to metabolic syndrome and aging.

Borago officinalis seed oil (BSO), a natural source of omega-6 fatty acids, attenuates fat accumulation by activating peroxisomal beta-oxidation both in C. elegans and in diet-induced obese rats

Obesity is a medical condition with increasing prevalence, characterized by an accumulation of excess fat that could be improved using some bioactive compounds. However, many of these compounds with in vitro activity fail to respond in vivo, probably due to the sophistication of the physiological energy regulatory networks. In this context, C. elegans has emerged as a plausible model for the identification and characterization of the effect of such compounds on fat storage in a complete organism. However, the results obtained in such a simple model are not easily extrapolated to more complex organisms such as mammals, which hinders its application in the short term. Therefore, it is necessary to obtain new experimental data about the evolutionary conservation of the mechanisms of fat loss between worms and mammals. Previously, we found that some omega-6 fatty acids promote fat loss in C. elegans by up-regulation of peroxisomal fatty acid β-oxidation in an omega-3 independent manner. In this work, we prove that the omega-6 fatty acids' effects on worms are also seen when they are supplemented with a natural omega-6 source (borage seed oil, BSO). Additionally, we explore the anti-obesity effects of two doses of BSO in a diet-induced obesity rat model, validating the up-regulation of peroxisomal fatty acid β-oxidation. The supplementation with BSO significantly reduces body weight gain and energy efficiency and prevents white adipose tissue accumulation without affecting food intake. Moreover, BSO also increases serum HDL-cholesterol levels, improves insulin resistance and promotes the down-regulation of Cebpa, an adipogenesis-related gene. Therefore, we conclude that the effects of omega-6 fatty acids are highly conserved between worms and obesity-induced mammals, so these compounds could be considered to treat or prevent obesity-related disorders.

Anti-obesity properties of the strain Bifidobacterium animalis subsp. lactis CECT 8145 in Zücker fatty rats

We evaluated the effect of oral administration of Bifidobacterium animalis subsp. lactis CECT 8145 strain in Zücker fatty rats. The Zücker fatty rats were randomly divided into two groups (n=10 each) and administered either B. animalis subsp. lactis CECT 8145 (1010 cfu/day) suspended in skim milk, or skim milk alone (control group). Each treatment was administered in drinking bottles from week 5 until week 17 of age. A lean Zücker rat group (standard group) was included to provide normal values for the Zücker strain. This group was administered skim milk in the drinking bottle for the same experimental period as Zücker fatty rats. Body weight gain was greater in the fatty control group than in the fatty rats treated daily with B. animalis subsp. lactis CECT 8145. Furthermore, dry and liquid food intake significantly decreased in the treated Zücker fatty group and these rats also showed decreased plasma ghrelin levels as compared with the Zücker fatty control group. B. animalis subsp. lactis CECT 8145 intake also decreased plasma tumour necrosis factor-α (a proinflammatory cytokine) and plasma malondialdehyde (a biomarker of oxidative stress). Moreover, the ratio plasma total cholesterol/plasma cholesterol transported by high-density lipoproteins, considered as an index for cardiovascular disease, also significantly decreased in the Zücker fatty rats treated with B. animalis subsp. lactis CECT 8145. By contrast, this bacterial strain significantly increased plasma adiponectin (an insulin-sensitising adipokine), but did not produce significant effects on triglyceride levels or glucose metabolism biomarkers. Although further research is required to confirm B. animalis subsp. lactis CECT 8145 is an efficient anti-obesity treatment in humans, the results obtained in this study are promising and point to the health and anti-obesity properties of this bacterial strain.

Probiotic administration improves sperm quality in asthenozoospermic human donors

The objective of this study is to analyse the effect of the ingestion of two selected antioxidant probiotics strains (Lactobacillus rhamnosus CECT8361 and Bifidobacterium longum CECT7347) on sperm quality parameters in asthenozoospermic males after three and six weeks of administration. Nine asthenozoospermic men without any medical treatment under similar diet conditions participated in the study. The quality of individual sperm samples was evaluated before (previous to ingestion), during (after 3 and 6 weeks of ingestion) and after probiotic administration (3 and 6 weeks after finishing the treatment). Sperm motility was evaluated by computer-assisted sperm analysis system, DNA fragmentation by sperm chromatin structure assay, cell viability by flow cytometry and measurement of intracellular H₂O₂ (reactive oxygen species; ROS) by flow cytometry using dichloro-dihydrofluorescein diacetate. Sperm motility was drastically improved after the treatment (approximately 6 fold change), DNA fragmentation was statistically reduced after probiotic administration from (approximately 1.2 fold change) and intracellular H₂O₂ level was decreased (approximately 3.5 fold change). Cell viability was not affected by the treatment. The significant improvement in sperm motility and the decrease in DNA fragmentation reported in this study provide preliminary evidence that probiotics could be administrated to improve motility and decrease DNA fragmentation and ROS levels in asthenozoospermic human males.