Coculture Strategy for Developing Lactobacillus paracasei PS23 Fermented Milk with Anti-Colitis Effect

Recent updates of probiotic dairy-based beverages

There is a rapid paradigm shift in the food consumption habits of consumers globally. The interest in healthier, safer, minimally processed and nature-identical foods is the driving force of this paradigm shift. Although the roots of this consumer trend go back further, especially the Covid-19 pandemic has contributed to the acceleration of this process. The effects of probiotics on human health have been known for many years. The commercial success of some probiotic microorganism strains, supported by clinical studies, is also evident. Probiotic microorganisms can be found in commercial products in a wide range of forms including powder, tablets or incorporated into liquid or solid food matrices. Milk and dairy products are suitable vehicles for the delivery of probiotics into the human body. Apart from well-established dairy-based probiotic foods including yogurt and yogurt-type beverages, in recent years some dairy products supplemented or enhanced with postbiotics and paraprobiotics are gaining popularity. The incorporation of next-generation probiotics in probiotic beverage formulations has also attracted the attention of researchers. The current state-of-the art for the utilization of next-generation probiotics, postbiotics and paraprobiotics in dairy-based probiotic beverages is the main focus of this review. Conventional milk-, whey- and buttermilk-based probiotic beverages are also covered.

Efficacy of Lacticaseibacillus paracasei fermented milk on a model of constipation induced by loperamide hydrochloride in BALB/c mice

Currently, most studies focus on the functions of probiotic-fermented milk, whereas there are relatively few studies on the function of postbiotic-fermented milk in relieving constipation. In this study, we aimed to assess the modulation of constipation symptoms and its mechanism of action by different concentrations of Lacticaseibacillus paracasei-fermented milk as a postbiotic in a loperamide hydrochloride-induced constipation model in BALB/c mice. By comparing the relevant indexes, colon histological analysis, gene expression level, and intestinal flora structure in the constipation model of mice, we found that high and ultra-high doses of fermented milk can effectively relieve constipation. Fermented milk effectively reduced defecation time, increased the rate of small intestinal propulsion in constipated mice, and alleviated colonic inflammation, safeguarding the normal function of the intestinal tract. In addition, it can regulate the intestinal flora, downregulate the abundance of Proteobacteria, upregulate the abundance of species of Firmicutes and Actinobacteriota, and improve the overall abundance level of intestinal flora in mice.

Oat-based postbiotics ameliorate high-sucrose induced liver injury and colitis susceptibility by modulating fatty acids metabolism and gut microbiota

High-sucrose (HS) consumption leads to metabolic disorders and increases susceptibility to colitis. Postbiotics hold great potentials in combating metabolic diseases and offer advantages in safety and processability, compared with living probiotics. We developed innovative oat-based postbiotics and extensively explored how they could benefit in rats with long-term high-sucrose consumption. The postbiotics fermented with Lactiplantibacillus plantarum (OF-1) and OF-5, the one fermented with the optimal selection of five probiotics (i.e., L. plantarum, Limosilactobacillus reuteri, Lacticaseibacillus rhamnosus, Lactobacillus acidophilus, and Bifidobacterium lactis) alleviated HS induced liver injury, impaired fatty acid metabolism and inflammation through activating AMPK/SREBP-1c pathways. Moreover, oat-based postbiotics restored detrimental effects of HS on fatty acid profiles in liver, as evidenced by the increases in polyunsaturated fatty acids and decreases in saturated fatty acids, with OF-5 showing most pronounced effects. Furthermore, oat-based postbiotics prevented HS exacerbated susceptibility to dextran sodium sulfate caused colitis and reconstructed epithelial tight junction proteins in colons. Oat-based postbiotics, in particular OF-5 notably remodeled gut microbiota composition, e.g., enriching the relative abundances of Akkermansia, Bifidobacterium, Alloprevotella and Prevotella, which may play an important role in the liver-colon axis responsible for improvements of liver functions and reduction of colitis susceptibility. The heat-inactivated probiotics protected against HS-induced liver and colon damage, but such effects were less pronounced compared with oat-based postbiotics. Our findings emphasize the great value of oat-based postbiotics as nutritional therapeutics to combat unhealthy diet induced metabolic dysfunctions.

The Potential Impact of Probiotics on Human Health: An Update on Their Health-Promoting Properties

Probiotics, known to be live microorganisms, have been shown to improve or restore the gut microbiota, which in turn has been linked to improved health. It is believed that probiotics are the modern equivalent of a panacea, with claims that they may treat or prevent different diseases both in children and adults (e.g., from colic in babies to cardiovascular disease, respiratory infection, and cancer in adults). Ever since the early 2000s, probiotic-based fermented foods have had a resurgence in popularity, mostly due to claims made regarding their health benefits. Fermented foods have been associated with the prevention of irritable bowel syndrome, lactose intolerance, gastroenteritis, and obesity, but also other conditions such as chronic diarrhea, allergies, dermatitis, and bacterial and viral infections, all of which are closely related to an unhealthy lifestyle. Recent and ongoing developments in microbiome/microbiota science have given us new research directions for probiotics. The new types, mechanisms, and applications studied so far, and those currently under study, have a great potential to change scientific understanding of probiotics' nutritional applications and human health care. The expansion of fields related to the study of the microbiome and the involvement of probiotics in its improvement foreshadow an era of significant changes. An expanding range of candidate probiotic species is emerging that can address newly elucidated data-driven microbial niches and host targets. In the probiotic field, new variants of microbiome-modulating interventions are being developed, including prebiotics, symbiotics, postbiotics, microbial consortia, live biotherapeutic products, and genetically modified organisms, with renewed interest in polyphenols, fibers, and fermented foods to ensure human health. This manuscript aims to analyze recent, emerging, and anticipated trends in probiotics (sources, doses, mechanism of action, diseases for which probiotics are administered, side effects, and risks) and create a vision for the development of related areas of influence in the field.

Heat-Killed Lacticaseibacillus paracasei Repairs Lipopolysaccharide-Induced Intestinal Epithelial Barrier Damage via MLCK/MLC Pathway Activation

Intestinal epithelial barrier function is closely associated with the development of many intestinal diseases. Heat-killed Lacticaseibacillus paracasei (HK-LP) has been shown to improve intestinal health and enhance immunity. However, the function of HK-LP in the intestinal barrier is still unclear. This study characterized the inflammatory effects of seven HK-LP (1 μg/mL) on the intestinal barrier using lipopolysaccharide (LPS) (100 μg/mL)-induced Caco-2 cells. In this study, HK-LP 6105, 6115, and 6235 were selected, and their effects on the modulation of inflammatory factors and tight junction protein expression (claudin-1, zona occludens-1, and occludin) were compared. The effect of different cultivation times (18 and 48 h) was investigated in response to LPS-induced intestinal epithelial barrier dysfunction. Our results showed that HK-LP 6105, 6115, and 6235 improved LPS-induced intestinal barrier permeability reduction and transepithelial resistance. Furthermore, HK-LP 6105, 6115, and 6235 inhibited the pro-inflammatory factors (TNF-α, IL-1β, IL-6) and increased the expression of the anti-inflammatory factors (IL-4, IL-10, and TGF-β). HK-LP 6105, 6115, and 6235 ameliorated the inflammatory response. It inhibited the nuclear factor kappa B (NF-κB) signaling pathway-mediated myosin light chain (MLC)/MLC kinase signaling pathway by downregulating the Toll-like receptor 4 (TLR4)/NF-κB pathway. Thus, the results suggest that HK-LP 6150, 6115, and 6235 may improve intestinal health by regulating inflammation and TJ proteins. Postbiotics produced by these strains exhibit anti-inflammatory properties that can protect the intestinal barrier.

Are heat-killed probiotics more effective than live ones on colon length shortness, disease activity index, and the histological score of an inflammatory bowel disease-induced murine model? A meta-analysis

This study was conducted to compare the efficiency of heat-killed and live probiotics against colon length shortness, disease activity index (DAI), and the histological score of an inflammatory bowel disease (IBD) via a meta-analysis. In February 2022, the eligible papers were collected from four databases (Google Scholar, PubMed, ScienceDirect, and Scopus). Using common- and random-effects models, the effect sizes were estimated throughout the standardized mean difference. Forty-three papers were recorded for our meta-analysis, and the heterogeneity of the effect sizes was determined with Cochran's Q test, followed by meta-ANOVA and meta-regression analyses. The probiotics (live and heat-killed) had globally an improving or preventive effect on colon length shortness, DAI, and histological score. The sub-group analysis revealed that the heat-killed probiotics had statistically (P > .05) the same improving effect on colon length shortness, DAI, and histological score as live probiotics. In conclusion, this study suggested that live and heat-killed probiotics had a similar impact on IBD symptoms investigated in this study. The present outcomes would be a good base for researchers willing to further compare the effects of live and heat-killed probiotics on IBD.

Safety Evaluation and Anti-Inflammatory Efficacy of Lacticaseibacillus paracasei PS23

Lacticaseibacillus paracasei strain PS23 (PS23) exhibits some probiotic properties. In this study, a genomic analysis of PS23 revealed no genes related to virulence or antibiotic resistance. Moreover, ornithine decarboxylase activity was not detected in vitro. In addition, PS23 was sensitive to the tested antibiotics. Genotoxicity tests for PS23 including the Ames test and chromosomal aberrations in vitro using Chinese hamster ovary cells and micronuclei in immature erythrocytes of ICR mice were all negative. Moreover, following a 28-day study involving repeated oral dose toxicity tests (40, 400, and 4000 mg/kg equal 1.28 × 10¹⁰, 1.28 × 10¹¹, and 1.28 × 10¹² CFU/kg body weight, respectively) using an ICR mouse model, no adverse effects were observed from any doses. In addition, supplementation with live or heat-killed PS23 ameliorates DSS-induced colonic inflammation in mice. Our findings suggest that PS23 is safe and has anti-inflammatory effects and may therefore have therapeutic implications.

Live and Heat-Killed Probiotic Lactobacillus paracasei PS23 Accelerated the Improvement and Recovery of Strength and Damage Biomarkers after Exercise-Induced Muscle Damage

Excessive, high-intensity or inappropriate exercise may cause muscle damage. How to speed up recovery and reduce exercise discomfort are currently very important issues for athletes and sports people. Past research has shown that probiotics can improve inflammation and oxidative stress, as well as improve exercise performance and antifatigue. However, further research is needed to confirm the recovery benefits for muscle damage. In this double-blind design study, all subjects were randomly assigned to placebo, a live Lactobacillus paracasei group (L-PS23, 2 × 1010 colony forming unit (CFU)/day), or a heat-killed L. paracasei group (HK-PS23, 2 × 1010 cells/day), and supplemented for six consecutive weeks. Afterwards, subjects completed 100 maximal vertical jumps to bring about exercise-induced muscle damage (EIMD). Countermovement jump (CMJ), isometric mid-thigh pull (IMTP), and Wingate anaerobic test (WAnT), as well as blood tests for markers of muscle damage and inflammation were made pre-exercise and 3, 24, 48 h post exercise. The results show that both L-PS23 and HK-PS23 supplementation significantly slowed the loss of muscle strength after muscle injury, and they significantly reduced the production of markers of muscle damage and inflammation (p < 0.05). In addition, L-PS23 and HK-PS23 had the benefits of accelerating the recovery and improvement of muscle strength, the blood markers of muscle injury and inflammation, and slowing the decline in testosterone concentrations (p < 0.05). Especially in the HK-PS23 supplemented group, there was a better trend. In conclusion, we found that L-PS23 or HK-PS23 supplementation for six weeks prevented strength loss after muscle damage and improved blood muscle damage and inflammatory markers, with protective, accelerated recovery and anti-fatigue benefits.

Dairy-Based Probiotic-Fermented Functional Foods: An Update on Their Health-Promoting Properties

Numerous studies have shown a link between the consumption of fermented dairy foods and improved health outcomes. Since the early 2000s, especially probiotic-based fermented functional foods, have had a revival in popularity, mostly as a consequence of claims made about their health benefits. Among them, fermented dairy foods have been associated with obesity prevention and in other conditions such as chronic diarrhea, hypersensitivity, irritable bowel syndrome, Helicobacter pylori infection, lactose intolerance, and gastroenteritis which all are intimately linked with an unhealthy way of life. A malfunctioning inflammatory response may affect the intestinal epithelial barrier’s ability to function by interfering with the normal metabolic processes. In this regard, several studies have shown that fermented dairy probiotics products improve human health by stimulating the growth of good bacteria in the gut at the same time increasing the production of metabolic byproducts. The fermented functional food matrix around probiotic bacteria plays an important role in the survival of these strains by buffering and protecting them from intestinal conditions such as low pH, bile acids, and other harsh conditions. On average, cultured dairy products included higher concentrations of lactic acid bacteria, with some products having as much as 109/mL or g. The focus of this review is on fermented dairy foods and associated probiotic products and their mechanisms of action, including their impact on microbiota and regulation of the immune system. First, we discussed whey and whey-based fermented products, as well as the organisms associated with them. Followed by the role of probiotics, fermented-product-mediated modulation of dendritic cells, natural killer cells, neutrophils, cytokines, immunoglobulins, and reinforcement of gut barrier functions through tight junction. In turn, providing the ample evidence that supports their benefits for gastrointestinal health and related disorders.

Lactobacillus paracasei PS23 improves cognitive deficits via modulating the hippocampal gene expression and the gut microbiota in D-galactose-induced aging mice

Probiotic supplements are potential therapeutic agents for age-related cognitive deficits. A prior study showed that probiotic Lactobacillus paracasei PS23 (PS23) supplementation delayed age-related cognitive decline in mice. However, the underlying mechanisms remain unclear. This study aimed to investigate the effects of live or heat-killed PS23 (HK-PS23) on cognitive function in D-galactose (D-gal)-induced aging mice and explore the underlying mechanisms. We designed four groups of mice: control, D-gal aging mice, and PS23 supplemented and HK-PS23 supplemented D-gal aging mice. We evaluated memory function and anxiety using Morris water maze and open field tests, respectively. Neural monoamines and activities of superoxide dismutase (SOD) in the hippocampus were evaluated. RNA-seq was used to evaluate hippocampal gene expression profiles in each group, and the composition of the gut microbiota was analyzed. We revealed that PS23 and HK-PS23 supplementation ameliorated D-gal-induced memory deficits and improved motor and anxiety-behaviors in aging mice. In the hippocampus, serotonin levels (5-HT) were increased and the genes involved in neuroplasticity, anti-inflammatory, and antioxidant functions were upregulated in PS23 and HK-PS23 supplemented groups. The gut microbiota showed specific changes. Our results suggest that PS23 and HK-PS23 supplements could ameliorate age-related cognitive decline, possibly by upregulating the genes involved in synaptic plasticity and preventing oxidation and inflammation.