Probiotics have been shown to possess anti-inflammatory effects in the gut by directly reducing the production of pro-inflammatory
cytokines and by secreting anti-inflammatory molecules. However, their systemic anti-inflammatory effects have not been thoroughly investigated. In this study, we aimed to develop probiotics that have efficacy in both intestinal and
lung inflammation. Lactobacillus plantarum KC3 (KC3), which was isolated from kimchi, was selected as a pre-candidate based on its inhibitory effects on the production of pro-inflammatory
cytokines in vitro. To further validate the effectiveness of KC3, we used ear
edema, DSS-induced
colitis, and
ambient particulate-matter-induced
lung inflammation models. First, KC3 exhibited direct anti-inflammatory effects on intestinal cells with the inhibition of IL-1β and TNF-α production. Additionally, KC3 treatment alleviated ear
edema and DSS-induced
colic inflammation, improving colon length and increasing the number of regulatory T cells. Beyond its local intestinal anti-inflammatory activity, KC3 inhibited pro-inflammatory
cytokines in the bronchoalveolar fluid and prevented neutrophil infiltration in the lungs. These results suggest that KC3 could be a potential functional ingredient with respiratory protective effects against
air-pollutant-derived
inflammation, as well as for the treatment of local gut disorders.