Liyan Kaiyin Formula relieves reflux pharyngitis by regulating M1 macrophage polarization via the NF-κB/NLRP3 pathway.

Background: We aimed to investigate whether Liyan Kaiyin Formula (LYKYF) can relieve reflux pharyngitis in rats by regulating M1 macrophage polarization via the nuclear factor-κB (NF-κB)/Nod-like receptor protein 3 (NLRP3) pathway.

Methods: Forty rats were randomized into a sham group, a laryngopharyngeal reflux disease (LPRD) group, a LYKYF group and a LYKYF+CHPG group (n = 10). Enzyme-linked immunosorbent assay was conducted to measure the serum levels of inflammatory factors interleukin-6 (IL-6), IL-1β and tumor necrosis factor-α (TNF-α). Western blotting and reverse transcription-polymerase chain reaction (RT-PCR) were performed to measure the expressions of proteins implicated in NF-κB/NLRP3 pathway. Western blotting was also used for the detection of M1 macrophage markers (CD86 and iNOS).

Results: Compared to the sham group, TNF-α, IL-6 and IL-1β levels in the serum, proportion of M1 macrophages in pharyngeal tissues, p-NF-κB p65/p65 ratio, protein expressions of NLRP3, Caspase-1, Apoptosis-associated speck-like protein (ASC), cluster of differentiation 86 (CD86) and inducible nitric oxide synthase, and mRNA expressions of NF-κB p65, NLRP3, Caspase-1 and ASC in the LPRD group exhibited significant elevations (P < 0.05). Compared with the LYKYF group, the LYKYF+CHPG group had significant elevations in serum TNF-α, IL-6 and IL-1β levels, proportion of M1 macrophages in pharyngeal tissues, p-NF-κB p65/p65 ratio, protein expressions of NLRP3, Caspase-1, ASC, CD86 and iNOS, as well as NF-κB p65, NLRP3, Caspase-1 and ASC mRNA expressions (P < 0.05). The identified key target genes were significantly enriched in GO terms associated with signal transduction, protein phosphorylation regulation, and adaptive responses to external stimuli.

Conclusion: LYKYF may suppress M1 macrophage polarization through suppressing the NF-κB/NLRP3 pathway activation, thereby alleviating reflux pharyngitis in rats.