Shenling Baizhu Powder Alleviated Lung Damage and Enhanced Immunoregulatory Activity in Mice with Non-Tuberculosis Mycobacterial Lung Disease.

OBJECTIVE: To investigate the effects of Shenling Baizhu Powder (SLBZP) on non-tuberculous mycobacteria (NTM)-induced lung disease in mice.

METHODS: An NTM lung disease mouse model was established by Mycobacterium kansasii infection. C57BL/6J female mice were randomly divided into 5 groups by a random number table (n=6): negative control, NTM, SLBZP-L (2.34 g/kg), SLBZP-H (4.68 g/kg), and rifampicin (20 mg/kg). M. kansasii load in the lungs, liver, and spleen was quantified. Lung histology was performed using hematoxylin and eosin staining. Gene and cytokine expressions related to CD4T and natural killer (NK) cells were detected by enzyme linked immunosorbent assay, flow cytometry, real-time quantitative reverse transcription PCR, and Western blot, respectively.

RESULTS: SLBZP-L and SLBZP-H treatments inhibited M. kansasii growth and reduced the histological damage and granuloma lesion areas in lungs of mice (P<0.01). SLBZP-H increased interleukin (IL)-17A and interferon-gamma (IFN-&#x3b3;) levels, along with the proportion of CD4T cells, NK cells, and IFN-&#x3b3;NK cells, while decreased IL-10 (P<0.01). Furthermore, SLBZP-H inhibited mRNA levels of tumor necrosis factor, IL-6, IL-1&#x3b2;, C-C motif chemokine ligand 2, C-X-C motif chemokine ligand (CXCL) 2, GATA binding protein 3 and T-bet, and increased mRNA level of retinoic acid receptor-related orphan receptor &#x3b3; (P<0.05 or P<0.01). SLBZP-L and SLBZP-H also reduced the protein expressions of CXCL13 and C-X-C chemokine receptor type 5 (P<0.05 or P<0.01).

CONCLUSION: SLBZP alleviated NTM-induced lung damage and enhanced NK cell immune response, which might be linked to CD4T cell immunity.