Lacticaseibacillus paracsei HY7207 Alleviates Hepatic Steatosis, Inflammation, and Liver Fibrosis in Mice with Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty acid disease (NAFLD) is caused by a build-up of fat in the liver, inducing local inflammation and fibrosis. We evaluated the effects of probiotic lactic acid-generating bacteria (LAB) derived from a traditional fermented beverage in a mouse model of NAFLD. The LAB isolated from this traditional Korean beverage were screened using the human hepatic cell line HepG2, and Lactocaseibacillus paracasei HY7207 (HY7207), which was the most effective inhibitor of fat accumulation, was selected for further study. HY7207 showed stable productivity in industrial-scale culture. Whole-genome sequencing of HY7207 revealed that the genome was 2.88 Mbp long, with 46.43% GC contents and 2778 predicted protein-coding DNA sequences (CDSs). HY7207 reduced the expression of lipogenesis and hepatic apoptosis-related genes in HepG2 cells treated with palmitic acid. Furthermore, the administration of 109 CFU/kg/day of HY7207 for 8 weeks to mice fed an NAFLD-inducing diet improved their physiologic and serum biochemical parameters and ameliorated their hepatic steatosis. In addition, HY7207 reduced the hepatic expression of genes important for lipogenesis (Srebp1c, Fasn, C/ebpa, Pparg, and Acaca), inflammation (Tnf, Il1b, and Ccl2), and fibrosis (Col1a1, Tgfb1, and Timp1). Finally, HY7207 affected the expression of the apoptosis-related genes Bax (encoding Bcl2 associated X, an apoptosis regulator) and Bcl2 (encoding B-cell lymphoma protein 2) in the liver. These data suggest that HY7207 consumption ameliorates NAFLD in mice through effects on liver steatosis, inflammation, fibrosis, and hepatic apoptosis. Thus, L. paracasei HY7207 may be suitable for use as a functional food supplement for patients with NAFLD.

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.

Development and validation of a PMA-qPCR method for accurate quantification of viable Lacticaseibacillus paracasei in probiotics.

The effectiveness of probiotic products hinges on the viability and precise quantification of probiotic strains. This study addresses this crucial requirement by developing and validating a precise propidium monoazide combination with quantitative polymerase chain reaction (PMA-qPCR) method for quantifying viable Lacticaseibacillus paracasei in probiotic formulations. Initially, species-specific primers were meticulously designed based on core genes from the whole-genome sequence (WGS) of L. paracasei, and they underwent rigorous validation against 462 WGSs, 25 target strains, and 37 non-target strains across various taxonomic levels, ensuring extensive inclusivity and exclusivity. Subsequently, optimal PMA treatment conditions were established using 25 different L. paracasei strains to effectively inhibit dead cell DNA amplification while preserving viable cells. The developed method exhibited a robust linear relationship (R 2 = 0.994) between cycle threshold (Cq) values and viable cell numbers ranging from 103 to 108 CFU/mL, with an impressive amplification efficiency of 104.48% and a quantification limit of 7.30 × 103 CFU/mL. Accuracy assessments revealed biases within ±0.5 Log10 units, while Bland-Altman analysis demonstrated a mean bias of 0.058 Log10, with 95% confidence limits of -0.366 to 0.482 Log10. Furthermore, statistical analysis (p = 0.76) indicated no significant differences between theoretical and measured values. This validated PMA-qPCR method serves as a robust and accurate tool for quantifying viable L. paracasei in various sample matrices, including pure cultures, probiotics as food ingredients, and composite probiotic products, thereby enhancing probiotic product quality assurance and contributing to consumer safety and regulatory compliance.

The Beneficial Effects of Lacticaseibacillus paracasei subsp. paracasei DSM 27449 in a Letrozole-Induced Polycystic Ovary Syndrome Rat Model.

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive age globally. Emerging evidence suggests that the dysregulation of microRNAs (miRNAs) and gut dysbiosis are linked to the development of PCOS. In this study, the effects of Lacticaseibacillus paracasei subsp. paracasei DSM 27449 (DSM 27449) were investigated in a rat model of PCOS induced by letrozole. The administration of DSM 27449 resulted in improved ovarian function, reduced cystic follicles, and lower serum testosterone levels. Alterations in miRNA expressions and increased levels of the pro-apoptotic protein Bax in ovarian tissues were observed in PCOS-like rats. Notably, the administration of DSM 27449 restored the expression of miRNAs, including miR-30a-5p, miR-93-5p, and miR-223-3p, leading to enhanced ovarian function through the downregulation of Bax expressions in ovarian tissues. Additionally, 16S rRNA sequencing showed changes in the gut microbiome composition after letrozole induction. The strong correlation between specific bacterial genera and PCOS-related parameters suggested that the modulation of the gut microbiome by DSM 27449 was associated with the improvement of PCOS symptoms. These findings demonstrate the beneficial effects of DSM 27449 in ameliorating PCOS symptoms in letrozole-induced PCOS-like rats, suggesting that DSM 27449 may serve as a beneficial dietary supplement with the therapeutic potential for alleviating PCOS.

Lactobacillus fermentation accelerated biotransformation of cranberry anthocyanins towards phenol-pyranoanthocyanins and their stability and antioxidant property.

Phenol-pyranoanthocyanins, a structurally modified type of anthocyanin, has higher stability than anthocyanins. However, their conversion occurs slowly. Therefore, it is crucial to improve the conversion efficiency and production of pyranoanthocyanins. In this study, cranberry anthocyanin (CRAN) was fermented using two Lactobacillus strains along with caffeic acid to form cranberry-derived pyranoanthocyanins (PY-CRAN). PY-CRAN was characterized and identified. The physicochemical properties, antioxidant activity, and tyrosinase inhibitory capacity of PY-CRAN were assessed. The results showed that phenol-pyranoanthocyanins can be rapidly produced through fermentative transformation using Lactiplantibacillus plantarum and Lacticaseibacillus paracasei. Lacticaseibacillus paracasei exhibits a higher propensity for producing phenol-pyranoanthocyanins. PY-CRAN exhibits high stability under light and various pH conditions. Moreover, they possess excellent antioxidant properties and the ability to inhibit tyrosinase. These results suggest that fermentative biotransformation conducted by Lactobacillus is an ideal method for producing cranberry pyranoanthocyanins. The resulting anthocyanins have potential as antioxidant and whitening agents, making them promising bioactive ingredients.

Assessment of Multifunctional Activity of a Postbiotic Preparation Derived from Lacticaseibacillus paracasei Postbiotic-P6.

Postbiotics possess various functional activities, closely linked to their source bacterial strains and preparation methods. Therefore, the functional activities of postbiotics need to be evaluated through in vitro and in vivo methods. This study aims to prepare a postbiotic and explore its antihemolytic, anti-inflammatory, antioxidant, and antibacterial activities. Specifically, a postbiotic preparation named PostbioP-6 was prepared by intercepting 1-5 kDa of Lacticaseibacillus paracasei Postbiotic-P6 fermentation broth. The results demonstrate that PostbioP-6 exhibited notable biological activities across multiple assays. It showed significant antihemolytic activity, with a 4.9-48.1% inhibition rate at 10-50% concentrations. Anti-inflammatory effects were observed both in vitro, where 8-40% PostbioP-6 was comparable to 259.1-645.4 µg/mL diclofenac sodium, and in vivo, where 3.5 and 4.0 µL/mL PostbioP-6 significantly reduced neutrophil counts in inflamed zebrafish (p < 0.05). Antioxidant properties were evident through increased reducing power (OD700 increased from 0.279 to 2.322 at 1.25-12.5% concentrations), DPPH radical scavenging activity (38.9-92.4% scavenging rate at 2.5-50% concentrations), and hydroxyl radical scavenging activity (4.66-10.38% scavenging rate at 0.5-4% concentrations). Additionally, PostbioP-6 demonstrated antimicrobial activity against two Gram-positive bacteria, eight Gram-negative bacteria, and one fungus. Furthermore, PostbioP-6 significantly inhibited the increase in peroxide value and malondialdehyde content in cookies, highlighting its potential application in food preservation. In conclusion, we prepared a novel postbiotic, termed PostbioP-6, which proved to have prominent anti-hemolytic, anti-inflammatory, antioxidant, and broad-spectrum antimicrobial activities. The multifunctional properties of PostbioP-6 position it as a potentially effective functional food supplement or preservative. In the future, further research is necessary to elucidate the precise mechanisms of action, identify the active components, and validate its biological activities in animal models or clinical trials.

Evaluating the Effect of Lacticaseibacillus paracasei Strain Shirota on the Physical Consistency of Stool in Healthy Participants with Hard or Lumpy Stools: A Double-Blind, Randomized, Placebo-Controlled Study.

We have earlier established a direct measurement method for assessing stool physical consistency using a texture analyzer (TAXT). The present study aimed to evaluate the stool softening effect of Lacticaseibacillus paracasei strain Shirota (LcS) using TAXT in a double-blind, randomized, placebo-controlled study. Sixty-four healthy participants with a Bristol stool form scale (BSFS) 1/2 ≥ 50% during screening consumed fermented milk containing LcS or a placebo beverage daily for 8 weeks. Stool consistency and water content were determined using TAXT and a lyophilizer, respectively. Participants evaluated their defecation using the BSFS. Stool consistency evaluated by a texture analyzer (TAXT) in the LcS group tended to be softer than that in the placebo group (p = 0.052). Subgroup analyses (TAXT value at baseline ≥ 4.5) showed that stool consistency was significantly softer in the LcS group (p = 0.014). Stool water content was also significantly higher in the LcS group than in the placebo group, but the proportion of normal stools was not statistically significant. We were unable to find evidence for the softening effect of LcS under the present study's conditions. However, its efficacy may be confirmed by targeting participants with physically hard stools and TAXT values ≥ 4.5.

Preventive effect of Lacticaseibacillus paracasei LMT18-32 on Porphyromonas gingivalis induced periodontitis.

Periodontitis is a severe gum infection leading to chronic inflammation in the gums, damage of tissues around teeth, and destruction of alveolar bones. Porphyromonas gingivalis is the major causative pathogen that induces periodontitis. Numerous probiotic bacteria are reported to produce antibacterial substances against pathogens especially oral pathogens, and these are proposed as preventive measures for periodontitis. In this study, Lacticaseibacillus paracasei LMT18-32 was evaluated and its antibacterial activity against P. gingivalis, and antioxidant activity in vitro were established. In addition, when L. paracasei LMT18-32 was administered to periodontitis induced mice, it successfully alleviated the alveolar bone loss and suppressed induced expression of proinflammatory and tissue destruction related genes in the gingival tissue. In conclusion, L. paracasei LMT18-32 is proposed as a potential probiotics to prevent periodontitis.

Contribution of Surface Adhesins of Lacticaseibacillus paracasei S-NB to Its Intestinal Adhesion and Colonization.

The intestinal retention and persistence of lactic acid bacteria (LAB) are strain-specific and affected by the bacterial surface components. However, the contribution of surface adhesins of LAB to intestinal adhesion and colonization remains unclear. In the present study, seven gene knockout mutants (genes related to surface adhesin synthesis) of Lacticaseibacillus paracasei S-NB were derived based on the Cre-lox-based recombination system. Results showed that the capsule layer appeared thinner in the cell wall of S-NBΔ7576, S-NBΔdlt, and S-NBΔsrtA mutants when compared with the wild-type (WT) S-NB. The effects of S-NB_7576 (wzd and wze genes, responsible for capsular polysaccharide synthesis) and S-NB_srtA (sortase A) mutation on the hydrophobicity, surface charge, and adhesion ability seem to vary strongly among seven mutant strains. In vivo colonization experiments showed a decrease in the colonization numbers of S-NBΔ7576 and S-NBΔsrtA in both the ileal and colon lumen from 2 to 8 days when compared with those of the WT S-NB. In conclusion, the synthesis of capsular polysaccharides and the transport of surface proteins are closely related to the adhesion ability and intestinal colonization of L. paracasei S-NB.

The Effect of the Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53 Combination (BN-202M) on Body Fat Percentage Loss in Overweight Individuals: A Randomized, Double-Blind, Placebo-Controlled Study.

BN-202M is derived from humans and consists of two strains, Lacticaseibacillus paracasei BEPC22 and Lactiplantibacillus plantarum BELP53. Body fat reduction effect and safety of BN-202M were assessed in overweight participants. A total of 150 participants were randomly assigned to the BN-202M and placebo groups at a 1:1 ratio. Dual-energy X-ray absorptiometry was used to objectively measure body fat. After 12 weeks of oral administration, the body fat percentage (-0.10 ± 1.32% vs. 0.48 ± 1.10%; p = 0.009) and body fat mass (-0.24 ± 1.19 kg vs. 0.23 ± 1.05 kg; p = 0.023) of the BN-202M group decreased significantly compared to those of the placebo group. The body weight (-0.58 kg, p = 0.004) and body mass index (BMI; -0.23, p = 0.003) was found to decrease significantly at 12 weeks in the BN-202M group, but not in the placebo group. Metabolome analysis revealed that ß-alanine, 3-aminoisobutyric acid, glutamic acid, and octopamine decreased in the weight-decreased BN-202M post-intake group. In the gut microbiota analysis, Akkermansia showed a statistically significant increase in the BN-202M group post-intake compared to the placebo group. No serious adverse events were observed in either group. These results suggest that BN-202M is safe and effective for reducing body fat and weight.

Structure characterization and immunological activity of capsular polysaccharide from live and heat-killed Lacticaseibacillus paracasei 6235.

Capsular polysaccharide (CPS) as a probiotic component has the ability to regulate the function of the host's immune system. However, how the structure and function of heat-killed CPS are altered remains unclear. In the present study, CPS were isolated and purified from live (LCPS) and heat-killed (HCPS) Lacticaseibacillus paracasei 6235. The differences in structure and immunomodulation between LCPS and HCPS were compared and analyzed. The results demonstrate that after heat killed, the molecular weight of CPS decreased from 23.4 kDa to 17.5 kDa, with the disappearance of galactosamine in the monosaccharide composition, and changes in the microstructure. Methylation analysis and nuclear magnetic resonance analysis revealed that the LCPS and HCPS are similar in structure, which main units of →3,4)-α-D-Glcp-(1→4)-α-D-Galp-(1→3)-ß-L-Rhap-(1→6)-ß-D-Galp-(1→, and repeating units of →3,4)-α-D-Glcp-(1→, →3)-ß-L-Rhap-(1→, and →4)-α-D-Galp-(1→ residues. Furthermore, both LCPS and HCPS significantly downregulated the expression of pro-inflammatory cytokines in RAW264.7 cells induced by LPS. Specifically, HCPS reduced the levels of IL-6 and IL-1ß by 79.38 % and 88.42 %, respectively, compared to LCPS. Concurrently, both LCPS and HCPS effectively mitigated inflammatory responses through the NF-κB and MAPK signaling pathways. Moreover, compared to LCPS, HCPS increased the protein expression levels of NF-κB/p-NF-κB and IκB/p-IκB by 26.14 % and 28.92 %, respectively. These results suggest that CPS has a role in modulating immune responses and that HCPS is more effective. This study can be further developed into new products related to postbiotics.

Anti-aging effects of Lacticaseibacillus paracasei PS117 on cognitive and intestinal health in naturally-aged mice: A focus on senescence-related proteins and microbiota composition.

The rising global aging population underscores the urgency of maintaining the health and well-being of the elderly while reducing the healthcare burden. Anti-aging probiotics have emerged as a promising strategy. This study identified a novel anti-senescence probiotic, Lacticaseibacillus paracasei PS117 (PS117). The effects of PS117 and heat-treated PS117 (HT-PS117) supplementation on cognitive function of naturally-aged male mice were investigated. It was found that PS117 supplementation improved the cognitive performance of aged mice in the Y-maze test. Furthermore, the level of senescence-related protein p16INK4a (p16) were reduced, while anti-senescence protein sirtuin 1 (Sirt1) were increased in the hippocampus. In addition, there was an overall improvement in the intestinal function. Distinct changes in the gut microbiota were also identified, suggesting a potential contribution to the beneficial effects of PS117 supplementation. In conclusion, these results suggest that PS117 supplements could improve cognitive and intestinal functions in naturally-aged mice, while HT-117 improves only intestinal function, possibly by improving the gut microbiota composition.

Exopolysaccharide from Lacticaseibacillus paracasei alleviates gastritis in Helicobacter pylori-infected mice by regulating gastric microbiota.

Introduction: Many probiotics have the ability to produce extracellular polysaccharides (EPS). EPS derived from these probiotics has been confirmed to regulate the host intestinal microecological balance and alleviate the symptoms of diseases caused by gastrointestinal microecological imbalance. Results: Lactic acid bacteria (LAB) strain with good exopolysaccharide (EPS) producing ability, namely, Lacticaseibacillus paracasei ZFM54 (L. paracasei ZFM54) was screened. The fermentation conditions of L. paracasei ZFM54 for EPS production were optimized. The EPS54 was characterized by chemical component and monosaccharide composition determination, UV, FT-IR and NMR spectra analysis. Cango red, SEM, AFM and XRD analysis were conducted to characterize the structure of EPS54. The EPS54 effectively reduced the colonization of Helicobacter pylori to AGS cells and recovered the cell morphology. EPS54 could also effectively alleviate the gastritis in the H. pylori-infected mice by down-regulating the mRNA expression levels of pro-inflammatory cytokines IL-6, IL-8, IL-1ß and TNF-α and up-regulating the mRNA expression of inflammatory cytokine IL-10 in gastric cells. EPS54 was also found to be able to positively regulate the structure of gastric microbiota. Conclusion: The EPS 54 from L. paracasei ZFM54 can alleviate gastritis in H. pylori-infected mice by modulating the gastric microbiota.

Cell wall polysaccharide enhances Lacticaseibacillus paracasei strain Shirota growth in milk and contributes to acid and bile tolerance.

LCPS-1, a cell wall polysaccharide (CWPS), is bound to the cell wall of the probiotic Lacticaseibacillus paracasei (formerly known as Lactobacillus casei) strain Shirota (LcS). Generally, the role of CWPS in the viability and survivability of bacteria is yet to be fully understood. This study aimed to elucidate the role of LCPS-1 in the viability and survivability of LcS. A mutant strain completely lacking LCPS-1 was constructed and evaluated for growth in bovine and soy milk and susceptibility to acid and bile. The growth of the mutant in bovine and soy milk temporarily stalled after the late logarithmic phase while wild-type LcS continued growing, resulting in a significantly lower number of viable cells for the mutant strain (p < 0.01). Significantly higher cell death relative to that of the wild-type strain was observed for the mutant strain following acid treatment at pH 3.0 (p < 0.01), with 60 and 92 % survival, respectively. The absence of LCPS-1 also reduced the survival rate of LcS cells from 3.3 to 0.8 % following 0.2 % bile treatment. The survival rate of the mutant after consecutive treatment with acid and bile was 19 %, while 73 % of the wild-type LcS survived. These results indicate that LCPS-1 leads to higher LcS growth in milk and improves tolerance to acid and bile. This study reveals the contribution of probiotic bacterial CWPS to acidic and gastrointestinal stress tolerance. Based on these findings, characterizing and modifying CWPS in probiotic strains could enhance manufacturing yields and improve gastrointestinal stress tolerance after consumption by hosts, ultimately advancing the development of more effective probiotics.

Complete genome sequence of the probiotic Lacticaseibacillus paracasei LPC100 strain from the NORDBIOTIC collection isolated from a human fecal sample.

We report the genome sequence of the human fecal isolate Lacticaseibacillus paracasei LPC100 from the NORDBIOTIC collection, comprising a 3.075 Mb chromosome and three plasmids (61 kb, 12 kb, and 7 kb). Genetic content reveals the strain's beneficial features-complete lactose metabolic pathway, potential production of bacteriocins, and short-chain fatty acids.

Lacticaseibacillus paracasei completely utilizes fructooligosacchrides in the human gut through ß-fructosidase (FosE).

The fecal microbiota of two healthy adults was cultivated in a medium containing commercial fructooligosaccharides [FOS; 1-kestose (GF2), nystose (GF3), and 1F-fructofuranosylnystose (GF4)]. Initially, the proportions of lactobacilli in the two feces samples were only 0.42% and 0.17%; however, they significantly increased to 7.2% and 4.8%, respectively, after cultivation on FOS. Most FOS-utilizing isolates could utilize only GF2; however, Lacticaseibacillus paracasei strain Lp02 could fully consume GF3 and GF4 too. The FOS operon (fosRABCDXE) was present in Lc. paracasei Lp02 and another Lc. paracasei strain, KCTC 3510T, but fosE was only partially present in the non-FOS-degrading strain KCTC 3510T. In addition, the top six upregulated genes in the presence of FOS were fosABCDXE, particularly fosE. FosE is a ß-fructosidase that hydrolyzes both sucrose and all three FOS. Finally, a genome-based analysis suggested that fosE is mainly observed in Lc. paracasei, and only 13.5% (61/452) of their reported genomes were confirmed to include it. In conclusion, FosE allows the utilization of FOS, including GF3 and GF4 as well as GF2, by some Lc. paracasei strains, suggesting that this species plays a pivotal role in FOS utilization in the human gut.

Indole-3-Lactic Acid Derived from Lacticaseibacillus paracasei Inhibits Helicobacter pylori Infection via Destruction of Bacteria Cells, Protection of Gastric Mucosa Epithelial Cells, and Alleviation of Inflammation.

Indole-3-lactic acid (ILA) has exhibited antimicrobial properties. However, its role in inhibiting Helicobacter pylori infection remains elusive. This study investigated the inhibitory effect of ILA produced by Lacticaseibacillus paracasei on H. pylori, which was further confirmed by cell and animal experiments. 5 mg/mL ILA was sufficient to directly inhibit the growth of H. pylori in vitro, with a urease inhibitory activity reaching 60.94 ± 1.03%, and the cell morphology and structure were destroyed. ILA inhibited 56.5% adhesion of H. pylori to GES-1 and significantly reduced the number of apoptotic cells. Furthermore, ILA suppresses H. pylori colonization by approximately 38% to 63%, reduced inflammation and oxidative stress in H. pylori-infected mice, and enhanced the enrichment and variety of gut microbiota, notably fostering the growth of beneficial bacteria such as Lactobacillus and Bifidobacterium strains. The results support that ILA derived from Lactobacillus can be applicated as a novel prebiotic in anti-H. pylori functional foods.

Potential Prebiotic Effect of Inulin-Enriched Pasta after In Vitro Gastrointestinal Digestion and Simulated Gut Fermentation.

In the current study, the prebiotic potential of an innovative functional pasta enriched with 12% (w/w) inulin was investigated. To this aim, pasta was subjected to in vitro gastrointestinal digestion followed by simulated gut fermentation compared to the control pasta (CTRL) not containing inulin. The incorporation of inulin positively (p < 0.05) affected some organoleptic traits and the cooking quality of the final product, giving an overall score significantly higher than CTRL. The resultant essential amino acid content was similar in both pasta samples while the total protein content was lower in inulin-enriched pasta for the polymer substitution to durum wheat flour. The prebiotic potential of chicory inulin was preliminarily tested in in vitro experiments using seven probiotic strains and among them Lacticaseibacillus paracasei IMPC2.1 was selected for the simulated gut fermentation studies. The positive prebiotic activity score registered with the probiotic strain suggested the suitability of the inulin-enriched pasta with respect to acting as a prebiotic source favoring the growth of the probiotic strain and short chain fatty acid (SCFA) production. The present study contributes to broadening knowledge on the prebiotic efficacy of inulin when incorporated into a complex food matrix.

Lacticaseibacillus paracasei LC86 mitigates age-related muscle wasting and cognitive impairment in SAMP8 mice through gut microbiota modulation and the regulation of serum inflammatory factors.

Purpose: Chronic inflammation contributes to the decline in muscle strength and cognitive abilities associated with aging. This study aims to clarify the effects of oral administration of Lacticaseibacillus paracasei LC86 on these age-related declines, as well as its impact on the composition of gut microbiota. Methods: Senescence-accelerated mouse prone 8 (SAMP8) mice received a 12 week regimen of LC86 (1 × 109 CFU/day). Muscle strength was assessed through forelimb grip strength and four-limb hanging tests. Cognitive function was evaluated through behavioral performance tests, and changes in gut microbiota were analyzed. Results: Administration of LC86 significantly enhanced muscle strength, demonstrated by increased grip strength and higher glycogen content in the gastrocnemius muscle (p = 0.041, p = 0.017, and p = 0.000, respectively). Behavioral tests suggested that LC86 mitigated age-related cognitive decline. Furthermore, there was a significant decrease in serum pro-inflammatory cytokines, such as IL-6, TNF-α, and MCP-1 (p = 0.002, p = 0.000, and p = 0.005, respectively), and an elevation in the anti-inflammatory cytokine IL-10 level (p = 0.000). An increase in hepatic antioxidant capacity was observed. Significant changes in the gut microbiota composition were noted, including increased populations of Bifidobacterium and Lactobacillus and decreased levels of Escherichia/Shigella and Bacteroides. Conclusion: The findings suggest that LC86 supplementation mitigates muscle weakness and cognitive impairment in aging SAMP8 mice, potentially through the modulation of inflammation and gut microbiota composition. LC86 emerges as a promising candidate for ameliorating the decline of muscular and cognitive functions associated with aging.

Effects of toothpaste containing inactivated Lacticaseibacillus paracasei Probio-01 on plaque-induced gingivitis and dental plaque microbiota.

Plaque-induced gingivitis is an inflammatory response in gingival tissues resulting from bacterial plaque accumulation at the gingival margin. Postbiotics can promote the proliferation of beneficial bacteria and optimise the state of microbiota in the oral cavity. In this study, we investigated the effect of inactivated Lacticaseibacillus paracasei Probio-01 on plaque-induced gingivitis and the dental plaque microbiota. A total of 32 healthy gingival participants (Group N, using blank toothpaste for 3 months) and 60 patients with plaque-induced gingivitis (30 in Group F, using inactivated Probio-01 toothpaste for 3 months, and 30 in Group B, using blank toothpaste for 3 months, respectively) were recruited. Clinical indices, which included bleeding on probing (BOP), gingival index (GI), and plaque index (PI), were used to assess the severity of gingivitis. Furthermore, 16SrDNA amplicon sequencing was used to explore changes in the gingival state and dental plaque microbiota in patients with plaque-induced gingivitis. The results showed that inactivated Probio-01 significantly reduced clinical indices of gingivitis, including BOP, GI, and PI, in participants with plaque-induced gingivitis and effectively relieved gingival inflammation, compared with that observed in the control group (group B). Inactivated Probio-01 did not significantly influence the diversity of dental plaque microbiota, but increased the relative abundance of dental plaque core bacteria, such as Leptotrichia and Fusobacterium (P < 0.05). Strong correlations were observed between the indices and abundance of dental plaque microbiota. Overall, the inactivated Probio-01 significantly reduced the clinical indices of gingivitis and effectively improved gingival inflammation in patients with plaque-induced gingivitis. The activity of inactivated Probio-01 against plaque-induced gingivitis was possibly mediated by its ability to regulate the dental plaque microbiota, as indicated by the close correlation between the plaque microbiota and clinical indices of gingivitis.