[Regan Saibisitan Granules alleviate airway inflammatory responses in asthmatic mice by regulating MAPK/NF-κB...

The aim of this paper was to explore the effect and mechanism of Regan Saibisitan Granules(RGS) on improving airway inflammatory responses in asthmatic mice by regulating the mitogen-activated protein kinase(MAPK)/nuclear factor-κB(NF-κB) signaling pathway. Female Balb/c mice were randomly divided into a blank group, a model group, low-, medium-and high-dose RGS groups(0.75, 1.5, and 3 g·kg~(-1)), dexamethasone group(3 mg·kg~(-1)), and a Feining Tablets group(0.72 g·kg~(-1)) according to body weight. The asthma model was established by ovalbumin(OVA) sensitization combined with aerosol challenge. The numbers of white blood cells(WBC), eosinophils(EOS), neutrophils(NEU), and lymphocytes(LYM) in bronchoalveolar lavage fluid(BALF) were counted. The levels of interleukin-4(IL-4), interleukin-5(IL-5), interleukin-13(IL-13), interferon-γ(INF-γ) in BALF, as well as the secretion of immunoglobulin E(IgE), tumor necrosis factor-α(TNF-α), and interleukin-1β(IL-1β) in serum, were detected using enzyme-linked immunosorbent assay(ELISA) kits. The pathological changes of lung tissue were observed by hematoxylin-eosin and periodic acid-Schiff staining to comprehensively evaluate the ameliorative effect of RGS on inflammation in asthmatic mice. The protein expression levels of phosphorylated extracellular signal-regulated kinase 1/2(p-ERK1/2), phosphorylated c-Jun N-terminal kinase(p-JNK), phosphorylated mitogen-activated protein kinase(p-p38), phosphorylated NF-κB(p-NF-κB), phosphorylated inhibitor of NF-κB α(p-IκBα), cleaved caspase-3 and B-cell lymphoma/leukemia-2-associated X protein(Bax) in lung tissue were detected by Western blot. The results showed that compared with the model group, the numbers of WBC, EOS, NEU and LYM in BALF of the RGS groups, the Feining Tablets group and the dexamethasone group decreased, and the content of IL-4, IL-5, IL-13 in BALF as well as the levels of IgE, TNF-α and IL-1β in serum significantly decreased. In addition, inflammatory cell infiltration, airway wall thickening, and mucus secretion were significantly alleviated, and the levels of p-ERK1/2, p-JNK, p-p38, p-NF-κB, p-IκBα, as well as the protein levels of cleaved caspase-3 and Bax in lung tissue of the RGS groups decreased. In conclusion, RGS may inhibit inflammatory response and cell apoptosis by regulating the MAPK/NF-κB signaling pathway, thereby alleviating airway inflammation in asthmatic mice.