As the relationship between the gut microbiome and allergies becomes better understood, targeted strategies to prevent and treat allergies through gut microbiome modulation are being increasingly developed. In the study presented herein, we screened various probiotics for their ability to inhibit mast cell degranulation and identified Lactiplatibacillus plantarum HD02 and MD159 as effective candidates. The two strains significantly attenuated vascular permeability induced by mast cell degranulation in a passive cutaneous anaphylaxis (PCA) model and, in the MC903-induced murine atopic dermatitis (AD) model, demonstrated comparable preventive effects against allergies, reducing blood levels of MCPT-1 (mast cell protease-1) and total IgE. In the house dust mite (HDM)-induced murine AD model, both L. plantarum HD02 and MD159 showed therapeutic effects, with L. plantarum HD02 demonstrating superior efficacy. Nevertheless, L. plantarum MD159 better suppressed transepidermal water loss (TEWL). Furthermore, L. plantarum HD02 and MD159 significantly increased the number of splenic Foxp3⁺ regulatory T cells, with L. plantarum MD159 having a more pronounced effect. However, only L. plantarum HD02 achieved a reduction in immune cells in the draining lymph nodes. Our findings highlight L. plantarum HD02 and MD159 as promising candidates for the prevention and treatment of allergies, demonstrating significant efficacy in suppressing mast cell degranulation, reducing the number of allergy biomarkers, and modulating immune responses in experimental models of AD. Their distinct mechanisms of action suggest potential complementary roles in addressing allergic diseases, underscoring their therapeutic promise in clinical applications.

Glucagon-like peptide-1 (GLP-1) is a hormone secreted from enteroendocrine cells that can promote weight loss and blood glucose improvement. We screened probiotic strains that effectively stimulate GLP-1 secretion from human enteroendocrine cells and then investigated the efficacy of this strain in a high-fat diet (HFD)-induced mouse model of obesity. Lactiplantibacillus plantarum GB104 greatly induced GLP-1 secretion by increasing expression of the proglucagon gene (GCG), but not the proprotein convertase subtilisin/kexin type 1 gene (PCSK1) in the human enteroendocrine cell line NCI-H716. In an HFD-induced mouse model of obesity, GB104 inhibited weight gain and improved blood glucose levels by increasing blood GLP-1 levels. It also tended to attenuate the HFD-induced changes in blood levels of other hormones and suppressed fat accumulation in the liver and adipose tissues. In white adipose tissue, GB104 suppressed inflammation by reducing pro-inflammatory M1 macrophages and increasing anti-inflammatory M2 macrophages and regulatory T cells. Probiotic strains that promote GLP-1 secretion, such as GB104, may serve as a promising candidate for dietary intervention against obesity and metabolic diseases.

Given the recognized involvement of the gut microbiome in the development of obesity, considerable efforts are being made to discover probiotics capable of preventing and managing obesity. In this study, we report the discovery of Lactiplantibacillus plantarum GBCC_F0227, isolated from fermented food, which exhibited superior triglyceride catabolism efficacy compared to L. plantarum WCSF1. Molecular analysis showed elevated expression levels of α/β hydrolases with lipase activity (abH04, abH08_1, abH08_2, abH11_1, and abH11_2) in L. plantarum GBCC_F0227 compared to L. plantarum WCFS1, demonstrating its enhanced lipolytic activity. In a high-fat-diet (HFD)-induced mouse obesity model, the administration of L. plantarum GBCC_F0227 mitigated weight gain, reduced blood triglycerides, and diminished fat mass. Furthermore, L. plantarum GBCC_F0227 upregulated adiponectin gene expression in adipose tissue, indicative of favorable metabolic modulation, and showed robust growth and low cytotoxicity, underscoring its industrial viability. Therefore, our findings encourage the further investigation of L. plantarum GBCC_F0227’s therapeutic applications for the prevention and treatment of obesity and associated metabolic diseases.