Sarcopenia is a condition in which there is a loss of muscle caused by aging and it is one of the most significant factors that affects physical fragility. In recent years, the role of the gut–muscle axis has garnered attention as, along with the gut microbiota, it potentially plays a significant role in muscle regeneration, in addition to nutritional supplements and exercise training. Past studies have found that supplementation with Lactobacillus plantarum TWK10 could effectively increase the muscle mass of animals or adult humans. Therefore, in this study, we investigated whether the supplementation of L. plantarum TWK10 produces increased muscle mass and improves the functional performance of elderly persons with mild fragility. A total of 68 elderly subjects were recruited, of which 13 subjects were excluded or withdrew from the study. We adopted a double-blind design, and the 55 subjects were randomly divided into three groups: the placebo group, the TWK10 low-dose group (2 × 10¹⁰ CFU/day) (TWK10-L), and the TWK10 high-dose group (6 × 10¹⁰ colony-forming unit (CFU)/day) (TWK10-H). For 18 weeks, all subjects were required to regularly take experimental samples, perform functional activity testing, and have their body composition analyzed before the study and every six weeks after the intervention. Finally, 17 subjects in the placebo group, 12 subjects in the TWK10-L group, and 13 subjects in the TWK10-H group finished the study. It was found that supplementation with TWK10 had a tendency to increase and improve muscle mass, left hand grip strength, lower limb muscle strength, and gait speed and balance after the sixth week, especially in the TWK10-H group, and, as the supplement time was longer up to the 18th week, it had an even greater effect (p < 0.05). In conclusion, consecutive supplementation of L. plantarum TWK10 for more than six weeks could effectively improve the muscle strength and endurance of the elderly, reducing sarcopenia and physical fragility. This trial was registered as NCT04893746.

Lactiplantibacillus plantarum TWK10 (TWK10), isolated from Taiwanese pickled cabbage, has been demonstrated to exert beneficial probiotic effects in both mice and humans. Here, we comprehensively assessed the safety of TWK10 using both in vivo and in vitro approaches, including whole-genome sequence analysis, an assessment of hemolytic activity, and performing an antimicrobial susceptibility test, the Ames bacterial reverse mutation assay, the chromosomal aberration test, a rodent peripheral blood micronucleus test, and the 28-day subacute oral toxicity assay. The results showed that there was no significant increase in the incidence of reverse mutations or chromosomal aberrations following exposure to TWK10. Moreover, no significant changes were detected either in the number of reticulocytes or the incidence of micronuclei in ICR mice, and no subacute toxicity was recorded in SD rats at the oral TWK10 dosage of 2000 mg/kg body weight/day repeated for 28 days. Additionally, TWK10 exhibited no hemolytic activity and was susceptible to all the antibiotics tested, except kanamycin. However, no antimicrobial resistance genes, virulence factors, or genes involved in biogenic amine synthesis were found in the genome of TWK10. Our findings demonstrated that TWK10 has high potential of being safe for human consumption as a probiotic.

Background: Osteoarthritis (OA) is a chronic condition characterized by joint pain and disability, driven by excessive oxidative stress and inflammatory cytokine production in chondrocytes, resulting in cell death and cartilage matrix breakdown. Our previous study showed that in monosodium iodoacetate (MIA)-induced OA rats, oral administration of heat-killed Lactobacillus delbrueckii subsp. lactis 557 (LDL557) could significantly decrease OA progression. Methods: Accordingly, we designed an in vitro cell culture study aimed at investigating the effects of heat-killed LDL557 extracts on chondrocytes using SW1353 cells (a human chondrosarcoma cell line) challenged with 5 μM MIA to mimic OA conditions. Results: The results showed that the 10 μg/mL LDL557 extracts protected SW1353 cells from MIA-induced death and reduced extracellular matrix (ECM) loss, as evaluated by toluidine blue O staining and extracellular matrix component synthesis with RT-qPCR measurement. This was achieved by decreasing the expression of MIA-induced pro-inflammatory cytokines, including IL-1β, IL-6, and TNF-α, while slightly increasing the MIA-suppressed expression of the anti-inflammatory cytokine IL-10, which were evidenced by RT-qPCR analysis. Moreover, the RT-qPCR evaluation also indicated that the LDL557 extracts slightly reduced the expression of COX-2 compared with the control, while it did not reduce the MIA-increased expression of microsomal prostaglandin E synthase-1 (mPGES-1). In addition, the LDL557 extracts influenced neither the matrix-degrading protease expressions measured via RT-qPCR nor the oxidative stress measured via fluorescence flow cytometry in the cells with or without the MIA challenge. Conclusions: This study demonstrates that LDL557 extracts may protect chondrocytes from OA damage by reducing inflammation-related factors and thus mitigating cartilage matrix loss, suggesting LDL557 extracts are attractive alternatives for OA applications.

Lactiplantibacillus plantarum LP28 (LP28), isolated from traditional Taiwanese dried tofu, has been demonstrated to have substantial probiotic potential because it increases the production of short-chain fatty acids (SCFAs) and strengthens anti-inflammatory responses. In this study, the safety of LP28 was assessed using both in vitro and in vivo approaches, including whole-genome sequence analysis, the Ames bacterial reverse mutation assay, a chromosomal aberration test, a rodent peripheral blood micronucleus test, a 28-day subacute oral toxicity assay, and an assessment of hemolytic activity. In vitro phenotypic evaluation revealed that LP28 exhibited no hemolytic activity and was susceptible to all the tested antibiotics except kanamycin. In vivo assessments revealed no significant alterations in reticulocyte counts or micronuclei incidence in ICR mice, and SD rats exhibited no subacute toxicity at an oral LP28 dosage of 2000 mg/kg body weight/day for 28 days. Moreover, a whole-genome sequence analysis of LP28 revealed the absence of antimicrobial resistance genes, harmful virulence factors, and genes associated with biogenic amine synthesis. Additionally, the presence of genes involved in stress responses (e.g., acid, bile salt, heat, osmotic, and oxidative stresses) and adhesion-related genes was confirmed. Furthermore, LP28 contains six genes (plnA, plnE, plnF, plnJ, plnK, and plnN) that encode bacteriocin precursor peptides, suggesting the potential for enhanced probiotic effects through the production of antimicrobial plantaricins. These findings highlight the potential of LP28 as a safe and effective probiotic for human consumption.

Low-grade body inflammation is a major cause of osteoarthritis (OA), a common joint disease. Gut dysbiosis may lead to systemic inflammation which can be prevented by probiotic administration. The Lactobacillus delbrueckii subsp. lactis 557 (LDL557) has been demonstrated to have beneficial effects for anti-inflammation. This study investigated the effects of LDL557 on OA progress using monosodium iodoacetate (MIA)-induced OA of rats. Live or heat-killed (HK)-LDL557 of a low or high dose was administrated for two weeks before MIA-induced OA, and then continuously administrated for another six weeks. After taking supplements for eight weeks, OA progress was analyzed. Results showed that MIA induced knee joint swelling, chondrocyte damage, and cartilage degradation, and supplementation with a high dose of LDL557 reduced MIA-induced knee joint swelling, chondrocyte damage, and cartilage degradation. Additionally, MIA increased serum levels of the matrix-degrading enzyme MMP-13, while a high dose of HK-LDL557 decreased it for the controls. Simultaneously, bone turnover markers and inflammatory cytokines of serum were assayed, but no significant differences were found except for a TNF-α decrease from a low dose of live LDL557. These results demonstrated that supplementation with high doses of live LDL557 or HK-LDL557 can reduce the progression of MIA-induced OA in rats.