Lactobacillus plantarum NK3 and Bifidobacterium longum NK49 Alleviate Bacterial Vaginosis and Osteoporosis in Mice by Suppressing NF-κB-Linked TNF-α Expression

Excessive expression of TNF-α worsens bacterial vaginosis (BV) and osteoporosis. Therefore, to understand whether probiotics could alleviate vaginosis and osteoporosis, we isolated anti-inflammatory Lactobacillus plantarum NK3 and Bifidobacterium longum NK49 from kimchi and human fecal lactic acid bacteria collection and examined their effects on Gardnerella vaginalis (GV)-induced vaginosis and ovariectomy-induced osteoporosis in female mice. Oral gavage of NK3 and/or NK49 significantly alleviated GV-induced vaginosis; these inhibited NF-κB activation and TNF-α expression in the vagina and uterus, and decreased the GV population in the vagina. Furthermore, treatment with NK3 and/or NK49 alleviated ovariectomy-induced osteoporosis and obesity; these increased blood calcium, phosphorus, and osteocalcin levels and suppressed body weight. GV-induced vaginosis and ovariectomy increased colonic myeloperoxidase activity, TNF-α expression, and fecal Proteobacteria population. NK3 and/or NK49 treatments reduced TNF-α expression and NF-κB activation in the colon. NK3 and NK49 treatment also restored GV- or ovariectomy-disrupted gut microbiota composition. In conclusion, NK3 and NK49 may simultaneously alleviate BV and osteoporosis by suppressing NF-κB-linked TNF-α expression through the regulation of gut microbiota population.