Protective Effects of a Novel Lactobacillus brevis Strain with Probiotic Characteristics against Staphylococcus aureus Lipoteichoic Acid-Induced Intestinal Inflammatory Response

Anti-Inflammatory Effect and Gut Health of Levilactobacillus brevis Strains in Macrophage and Intestinal Cells

This study evaluated the potential of Levilactobacillus brevis strains (20080 and G1) to alleviate intestinal inflammation and support gut health. Chronic inflammatory conditions are often associated with gut microbiota dysbiosis, suggesting a potential role for probiotics in its management. The anti-inflammatory effects of L. brevis strains were assessed in cellular models of systemic and intestinal inflammation using RAW 264.7 macrophages and HT-29 epithelial cells. In lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages, L. brevis strains suppressed pro-inflammatory cytokines and nitric oxide (NO) production while enhancing anti-inflammatory responses. Furthermore, the expression levels of prostaglandin E2 and leukotriene B4, which are key mediators of inflammatory diseases, particularly arthritis, were significantly reduced. Additionally, these strains effectively inhibited the activation of nuclear factor-κB, activator protein-1, and mitogen-activated protein kinase pathways, which are key regulators of inflammatory responses. In HT-29 cells, treatment with these strains led to a reduction in NO production upon sodium nitroprusside (SNP) stimulation. Under LPS stimulation, these strains suppressed the expression of pro-inflammatory cytokines and enhanced the expression of tight junction and mucin genes. In conclusion, L. brevis strains exhibited anti-inflammatory effects and gut-protective effects against intestinal inflammation, supporting their potential as therapeutic agents for inflammatory diseases.

Probiotic Lactiplantibacillus plantarum Lb41 alleviates high-fat diet-induced nonalcoholic fatty liver disease in mice

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is mainly related to genetics, obesity, insulin resistance, and type 2 diabetes. Probiotic Lactiplantibacillus plantarum Lb41 (Lb41) has not been reported to have hepatoprotective effects. Therefore, the aim of this study is to investigate the preventive effects of Lb41 against NAFLD in high-fat diet (HFD)-fed mice for preventing NAFLD.

METHOD

To induce fatty liver, the mice were given HFD for 5 weeks, followed by silymarin (200 mg/kg) or Lb41 (108 or 109 colony forming units/day) with the HFD for 7 weeks. After 12 weeks, body weight, histological change, serum and hepatic lipid profiles, etc. was performed compared to control and silymarin.

RESULTS

Lb41 had significantly reduced body weight (4.87 g) and serum lipids (triglycerides (77.64%), total cholesterol (67.53%), and low-density lipoprotein (40.50%) compared with the HFD group (P < 0.05). Lb41 significantly relieved HFD-associated hepatic injury by reducing aspartate transaminase (0.49-0.57 fold), alanine transaminase (0.49-0.51 fold), and alkaline phosphatase (0.76-0.90 fold) (P < 0.05). Additionally, they had decreased expression levels of peroxisome proliferator-activated receptor (PPAR) γ and sterol regulatory element-binding protein 1c and increased the expression levels of acyl-CoA oxidase, PPARα, carnitine palmitoyltransferase 1, acetyl CoA carboxylase 1, and fatty acid synthase in liver cells. Insulin and leptin levels decreased in the Lb41 treatment group compared with those in the HFD group. Meanwhile, adiponectin levels increased, similar to those in the normal diet group.

CONCLUSION

Based on these findings, Lb41 probiotics have possible hepatoprotective effects and could be used as functional food materials.

Anti-inflammatory effects of Lactiplantibacillus plantarum strains through MAPK, NF-κB, and AP-1 signaling pathways and its application in soy milk

This study investigated the anti-inflammatory effects of probiotic Lactiplantibacillus plantarum strains isolated from kimchi and its application in soy milk. L. plantarum WB3801 and L. plantarum WB3802 exhibited probiotic properties. Moreover, L. plantarum strains inhibited inducible nitric oxide synthase and cyclooxygenase-2 expression in RAW 264.7 murine macrophages without inducing cytotoxicity. This resulted in decreased nitric oxide and prostaglandin E2 levels. Additionally, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 mRNA levels were downregulated, and the activation of mitogen-activated protein kinase, nuclear factor-κB, and activator protein-1 was suppressed. Furthermore, fermented soy milk with fructooligosaccharides by L. plantarum strains exhibited stable physicochemical characteristics over the 28-day storage period, and its anti-inflammatory effects were consistent with those of the L. plantarum strains. Therefore, L. plantarum WB3801 and L. plantarum WB3802 can be utilized as functional components in foods with anti-inflammatory effects.

Antioxidant and Immunostimulatory Effects of Lactobacillus Strains in RAW 264.7 Macrophages via NF-κB and MAPK Signaling Pathways

Modern stressors such as stress, irregular lifestyles, lack of exercise, and poor eating habits weaken immunity, thereby increasing susceptibility to infections and chronic diseases. Probiotics are functional ingredients that regulate gut microbiota, enhance immune function, and reduce oxidative stress. In this study, we identified novel probiotic candidates with antioxidant and immunostimulatory properties. Lactiplantibacillus plantarum WB4304, L. plantarum WB4305, and Levilactobacillus brevis WB4306, isolated from the traditional fermented food kimchi, exhibited acid and bile salt tolerance and strong adhesion to HT-29 cells, suggesting their suitability for intestinal colonization. Their safety was confirmed through hemolytic activity, bile salt hydrolase activity, and antibiotic susceptibility assays. Notably, L. plantarum WB4304 and L. plantarum WB4305 exhibited higher radical scavenging activities than Lacticaseibacillus rhamnosus GG. These strains significantly enhanced nitric oxide (NO) production and phagocytosis in RAW 264.7 macrophages. Immune activation was mediated by upregulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α through the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Among the three strains, L. plantarum WB4304 and L. plantarum WB4305 exhibited the most pronounced immunostimulatory effects. These findings suggest the potential of L. plantarum WB4304, L. plantarum WB4305, and L. brevis WB4306 as safe and functional probiotics, with promising applications in oxidative stress management and immune health enhancement.

Heat-killed Lactiplantibacillus plantarum WB3813 and Lactiplantibacillus plantarum WB3814 Alleviate LPS-Induced Inflammatory Damage and Apoptosis in A549 Cells

Chronic obstructive pulmonary disease (COPD) is characterized by chronic lung inflammation and apoptosis. Although paraprobiotics are known for their beneficial effects on respiratory health, research on their effect on COPD is limited. In this study, we investigated the effects of heat-killed Lactiplantibacillus plantarum WB3813 and Lact. plantarum WB3814 on inflammation and apoptosis in lipopolysaccharide (LPS)-induced A549 cells. Both strains demonstrated appropriate probiotic properties and were confirmed to be safe. The results showed that heat-killed lactic acid bacteria (H-LAB) exhibited anti-inflammatory and anti-apoptotic effects. Although LPS exposure reduced cell viability, treatment with the two H-LAB demonstrated a protective effect on the cells. RT-PCR results showed that H-LAB pretreatment reduced COPD-related mRNA expression levels, and western blotting analysis indicated downregulation of the activation NF-κB and intrinsic apoptotic signaling pathways. Additionally, elevated levels of IL-6 and eotaxin induced by LPS decreased. Furthermore, the strains significantly lowered intracellular ROS levels, which were increased by LPS, and promoted radical-scavenging activity. Although the in vivo effects have not yet been elucidated, this study demonstrated that heat-killed or live Lact. plantarum WB3813 and Lact. plantarum WB3814 exhibit anti-inflammatory and anti-apoptotic effects in a lung epithelial cell injury model. These findings provide experimental evidence for the development of functional foods to improve bronchial health and for potential clinical applications in COPD treatment.

Biofortification, metabolomic profiling and quantitative analysis of vitamin B12 enrichment in guava juice via lactic acid fermentation using Levilactobacillus brevis strain KU15152

BACKGROUND

Chemical fortification and dose supplementation of vitamin B12 are widely implemented to combat deficiency symptoms. However, in situ, fortification of vitamin B12 in food matrixes can be a promising alternative to chemical fortification. The present study aimed to produce vitamin B12-rich, probiotic guava juice fermented with Levilactobacillus brevis strain KU15152. Pasteurized fresh guava juice was inoculated with 7.2 log CFU mL-1 L. brevis strain KU15152 and incubated for 72 h at 37 °C anaerobically. The antioxidants, total phenolic compounds, vitamin B12 production, sugars, organic acids, pH and viable count were analyzed at 24, 48 and 72 h of incubation. The fermented juice was stored at 4 °C, and the changes in its functional properties were analyzed at 7-day intervals up to 28 days of storage.

RESULTS

During fermentation, the bacteria cell count was increased from 7.01 ± 0.06 to 9.76 ± 0.42 log CFU mL-1 after 72 h of fermentation and was decreased to 6.94 ± 0.34 CFU mL-1 during storage at 4 °C after 28 days. The pH, total soluble solids, crude fiber, citric acid and total sugars decreased, while titratable acidity, total protein, antioxidants, phenolic compounds and lactic acid contents increased during fermentation. The fermented guava juice exhibited higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS)) radical scavenging activities (85.97% and 75.97%, respectively) at 48 h of fermentation. The concentration of active vitamin B12 in the sample reached 109.5 μg L-1 at 72 h of fermentation. However, this concentration gradually decreased to 70.2 μg L-1 during the storage period. During storage for 28 days at 4 °C, both the fermented and control guava juices exhibited a decline in antioxidant and phenolic compound concentrations. Furthermore, the addition of 20% honey and guava flavor enhanced the organoleptic properties and acceptability of fermented guava juice.

CONCLUSION

The value-added fermented guava juice could be a novel functional food product to combat vitamin B12 deficiency. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Heat-Killed Latilactobacillus sakei CNSC001WB and Lactobacillus pentosus WB693 Have an Anti-inflammatory Effect on LPS-Stimulated RAW 264.7 Cells

Excessive inflammatory results, such as those seen in rheumatoid arthritis and cardiovascular diseases, are known to cause various complications. Therefore, we aimed to investigate whether heat-killed Latilactobacillus sakei CNS001WB and Lactobacillus pentosus WB693 can prevent inflammatory reactions. When LPS-stimulated RAW 264.7 cells were handled with either heat-killed Lact. sakei CNSC001WB or Lact. pentosus WB693, the production of nitric oxide reduced. Furthermore, the expression of cyclooxygenase (COX)-2 and proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, and IL-6, was suppressed. The expression of prostaglandin E2 (PGE2) and leukotriene B4 (LTB4), which play important roles in inflammatory diseases, especially arthritis, was also reduced. Moreover, these strains inhibited nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways, which activate various cytokines and inflammatory mediators. Additionally, heat-killed Lact. sakei CNSC001WB and Lact. pentosus WB693 inhibited the reactive oxygen species (ROS) production. Based on these results, we concluded that heat-killed Lact. sakei CNSC001WB and Lact. pentosus WB693 sufficiently inhibited the inflammatory response and may have anti-inflammatory potential.

A critical review of novel antibiotic resistance prevention approaches with a focus on postbiotics

Antibiotic resistance is a significant public health issue, causing illnesses that were once easily treatable with antibiotics to develop into dangerous infections, leading to substantial disability and even death. To help fight this growing threat, scientists are developing new methods and techniques that play a crucial role in treating infections and preventing the inappropriate use of antibiotics. These effective therapeutic methods include phage therapies, quorum-sensing inhibitors, immunotherapeutics, predatory bacteria, antimicrobial adjuvants, haemofiltration, nanoantibiotics, microbiota transplantation, plant-derived antimicrobials, RNA therapy, vaccine development, and probiotics. As a result of the activity of probiotics in the intestine, compounds derived from the structure and metabolism of these bacteria are obtained, called postbiotics, which include multiple agents with various therapeutic applications, especially antimicrobial effects, by using different mechanisms. These compounds have been chosen in particular because they don't promote the spread of antibiotic resistance and don't include substances that can increase antibiotic resistance. This manuscript provides an overview of the novel approaches to preventing antibiotic resistance with emphasis on the various postbiotic metabolites derived from the gut beneficial microbes, their activities, recent related progressions in the food and medical fields, as well as concisely giving an insight into the new concept of postbiotics as "hyperpostbiotic".

Anti-inflammatory, antioxidant effects, and antimicrobial effect of Bacillus subtilis P223

This study aimed to investigate the anti-inflammatory, antioxidant, and antimicrobial effects of Bacillus subtilis P223 which is known to have probiotic properties. B. subtilis P223 that had been killed by heat in LPS-induced RAW 264.7 cells decreased nitric oxide (NO) production. Furthermore, it inhibited the expression of proinflammatory cytokines such interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α). Heat-killed B. subtilis P223 also inhibited the expression of the nuclear factor (NF)-κB cellular signaling pathway, and it showed reactive oxygen species (ROS) reduction. In DPPH, ABTS, and SOD assay, B. subtilis P223 showed a high antioxidant capacity, and inhibited the growth of skin related pathogens including Staphylococcus aureus and Propionibacterium acnes. This study therefore demonstrated the various functional properties of B. subtilis P223 as probiotics, and suggested the potential for its application as functional material.

Probiotic Pediococcus acidilactici Strains Exert Anti-inflammatory Effects by Regulating Intracellular Signaling Pathways in LPS-Induced RAW 264.7 Cells

This study investigated the anti-inflammatory effects of Pediococcus acidilactici strains isolated from fermented vegetables on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. In addition, the probiotic characteristics and safety were evaluated. Our results show that Ped. acidilactici strains possess high survivability in simulated gastrointestinal environments and strong attachment to HT-29 cells. All Ped. acidilactici strains exhibited γ-hemolysis and resistance to gentamicin, kanamycin, and streptomycin, a characteristic commonly observed in lactic acid bacteria. Treatment with Ped. acidilactici inhibited the expression of inducible nitric oxide synthase and cyclooxygenase-2, leading to a subsequent reduction in nitric oxide and prostaglandin E2 production. Furthermore, the strains downregulated interleukin (IL)-1β and IL-6 mRNA levels, ultimately suppressing their production. We demonstrated that Ped. acidilactici strains could modulate the activation of nuclear factor-κB, mitogen-activated protein kinase, and activator protein-1, which are known to regulate inflammatory responses. Consequently, the anti-inflammatory properties of Ped. acidilactici strains in this study support their potential application as therapeutic agents for inflammatory diseases, providing molecular insights into next-generation functional probiotic products.

Probiotics: Shaping the gut immunological responses

Probiotics are live microorganisms exerting beneficial effects on the host's health when administered in adequate amounts. Among the most popular and adequately studied probiotics are bacteria from the families Lactobacillaceae, Bifidobacteriaceae and yeasts. Most of them have been shown, both in vitro and in vivo studies of intestinal inflammation models, to provide favorable results by means of improving the gut microbiota composition, promoting the wound healing process and shaping the immunological responses. Chronic intestinal conditions, such as inflammatory bowel diseases (IBD), are characterized by an imbalance in microbiota composition, with decreased diversity, and by relapsing and persisting inflammation, which may lead to mucosal damage. Although the results of the clinical studies investigating the effect of probiotics on patients with IBD are still controversial, it is without doubt that these microorganisms and their metabolites, now named postbiotics, have a positive influence on both the host's microbiota and the immune system, and ultimately alter the topical tissue microenvironment. This influence is achieved through three axes: (1) By displacement of potential pathogens via competitive exclusion; (2) by offering protection to the host through the secretion of various defensive mediators; and (3) by supplying the host with essential nutrients. We will analyze and discuss almost all the in vitro and in vivo studies of the past 2 years dealing with the possible favorable effects of certain probiotic genus on gut immunological responses, highlighting which species are the most beneficial against intestinal inflammation.

Hepatoprotective Effect of Lactiplantibacillus plantarum DSR330 in Mice with High Fat Diet-Induced Nonalcoholic Fatty Liver Disease

Lactiplantibacillus plantarum DSR330 (DSR330) has been examined for its antimicrobials production and probiotics. In this study, the hepatoprotective effects of DSR330 were examined against non-alcoholic fatty liver disease (NAFLD) in a high-fat diet (HFD)-fed C57BL/6 mouse model. To induce the development of fatty liver, a HFD was administered for five weeks, and then silymarin (positive control) or DSR330 (108 or 109 CFU/day) was administered along with the HFD for seven weeks. DSR330 significantly decreased body weight and altered serum and hepatic lipid profiles, including a reduction in triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels compared to those in the HFD group. DSR330 significantly alleviated HFD-related hepatic injury by inducing morphological changes and reducing the levels of biomarkers, including AST, ALT, and ALP. Additionally, DSR330 alleviated the expression of SREBP-1c, ACC1, FAS, ACO, PPARα, and CPT-1 in liver cells. Insulin and leptin levels were decreased by DSR330 compared to those observed in the HFD group. However, adiponectin levels were increased, similar to those observed in the ND group. These results demonstrate that L. plantarum DSR330 inhibited HFD-induced hepatic steatosis in mice with NAFLD by modulating various signaling pathways. Hence, the use of probiotics can lead to hepatoprotective effects.

Complete genome sequence of Levilactobacillus brevis NSMJ23, makgeolli isolate with antimicrobial activity

We report the complete genome sequence of Levilactobacillus brevis NSMJ23 with probiotic properties. The final genome assembly consisted of a 2,389,998-bp chromosome and seven plasmids with 45.59% GC content, which comprised 2,624 genes including 2,457 protein coding sequences.

Anti-inflammatory activities of Levilactobacillus brevis KU15147 in RAW 264.7 cells stimulated with lipopolysaccharide on attenuating NF-κB, AP-1, and MAPK signaling pathways

Probiotics confer many beneficial effects on several illnesses, ranging from microbial diarrhea to inflammatory diseases. This study was conducted on whether Levilactobacillus brevis KU15147 obtained from kimchi has anti-inflammatory effects in RAW 264.7 cells stimulated with lipopolysaccharide (LPS) and antioxidant potential. L. brevis KU15147 reduced nitric oxide and prostaglandin E2 levels with decreasing the activation of inducible nitric oxide synthase and cyclooxygenase-2 without cell cytotoxicity. In addition, L. brevis KU15147 attenuated proinflammatory cytokine production including tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 in RAW 264.7 cells stimulated with LPS. Additionally, L. brevis KU15147 reduced the activity of nuclear factor-κB, activator protein-1, and mitogen-activated protein kinase signaling pathways. Furthermore, L. brevis KU15147 downregulated the production of reactive oxygen species. Therefore, L. brevis KU15147 was concluded that had an inhibition effect on LPS-induced inflammatory responses and can be used in functional foods to suppress inflammatory diseases.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01318-w.

Neuroprotective Effects of Heat-Killed Levilactobacillus brevis KU15152 on H2O2-Induced Oxidative Stress

This study proposed to demonstrate the neuroprotective effects of heat-killed Levilactobacillus brevis KU15152. Heat-killed L. brevis KU15152 showed antioxidant activity similar to that of Lacticaseibacillus rhamnosus GG, in terms of radical scavenging activity. To evaluate the neuroprotective effects, conditioned medium (CM) obtained by incubating heat-killed bacteria in intestinal cells (HT-29) was used through gut-brain axis. CM from L. brevis KU15152 protected neuroblastoma cells (SH-SY5Y) against H2O2-induced oxidative stress. Pretreatment with CM significantly alleviated the morphological changes induced by H2O2. Heat-killed L. brevis KU15152 showed an increased brain-derived neurotrophic factor (BDNF) expression in HT-29 cells. L. brevis KU15152-CM remarkably downregulated the Bax/Bcl-2 ratio, while upregulating the expression of BDNF and tyrosine hydroxylase (TH) in SH-SY5Y cells. Furthermore, L. brevis KU15152-CM reduced caspase-3 activity following H2O2 treatment. In conclusion, L. brevis KU15152 can be potentially used as food materials to avoid neurodegenerative diseases.

Gut microbiome in tumorigenesis and therapy of colorectal cancer

Colorectal cancer (CRC) is the malignant tumor with the highest incidence in the digestive system, and the gut microbiome plays a crucial role in CRC tumorigenesis and therapy. The gastrointestinal tract is the organ harboring most of the microbiota in humans. Changes in the gut microbiome in CRC patients suggest possible host-microbe interactions, thereby hinting the potential tumorigenesis, which provides new perspective for preventing, diagnosing, or treating CRC. In this review, we discuss the effects of gut microbiome dysbiosis on CRC, and reveal the mechanisms by which gut microbiome dysbiosis leads to CRC. Gut microbiome modulation with the aim to reverse the established gut microbial dysbiosis is a novel strategy for the prevention and treatment of CRC. In addition, this review summarizes that probiotic antagonize CRC tumorigenesis by protecting intestinal barrier function, inhibiting cancer cell proliferation, resisting oxidative stress, and enhancing host immunity. Finally, we highlight clinical applications of the gut microbiome, such as gut microbiome analysis-based biomarker screening and prediction, and microbe modulation-based CRC prevention, treatment enhancement, and treatment side effect reduction. This review provides the reference for the clinical application of gut microbiome in the prevention and treatment of CRC.

Levilactobacillus brevis KU15151 Inhibits Staphylococcus aureus Lipoteichoic Acid-Induced Inflammation in RAW 264.7 Macrophages

Inflammation is a host defense response to harmful agents, such as pathogenic invasion, and is necessary for health. Excessive inflammation may result in the development of inflammatory disorders. Levilactobacillus brevis KU15151 has been reported to exhibit probiotic characteristics and antioxidant activities, but the effect of this strain on inflammatory responses has not been determined. The present study aimed to investigate the anti-inflammatory potential of L. brevis KU15151 in Staphylococcus aureus lipoteichoic acid (aLTA)-induced RAW264.7 macrophages. Treatment with L. brevis KU15151 reduced the production of nitric oxide and prostaglandin E₂ by suppressing the expression of inducible nitric oxide synthase and cyclooxygenase-2. Additionally, the production of proinflammatory cytokines including tumor necrosis factor-α, interleukin (IL)-6, and IL-1β, decreased after treatment with L. brevis KU15151 in aLTA-stimulated RAW 264.7 cells. Furthermore, this strain alleviated the activation of nuclear factor-κB and mitogen-activated protein kinase signaling pathways. Moreover, the generation of reactive oxygen species was downregulated by treatment with L. brevis KU15151. These results demonstrate that L. brevis KU15151 possesses an inhibitory effect against aLTA-mediated inflammation and may be employed as a functional probiotic for preventing inflammatory disorders.