Effect of honokiol on PI3K/Akt signaling pathway in asthmatic mice and its effect on TLR2 and TLR4 expression / 中草药

ABSTRACT

Objective: To investigate the effect of honokiol on PI3K/Akt signaling pathway in asthmatic mice and its effect on TLR2 and TLR4 expression. Methods Fifty ICR mice were randomly divided into normal control group, asthma model group, positive control group (dexamethasone 10 mg/kg, ip), and honokiol high and low dose (50 μg/kg and 10 μg/kg, ip) groups. The asthma model was induced by ovalbumin plus aluminum hydroxide sensitization method, and then the corresponding drugs were administered for 7 d. The alveolar lavage fluid was collected and white blood cells were counted at 24 h after the last administration; The histopathological examinations of HE, PAS and Masson staining were performed. The expression of PI3K, Akt, p-Akt, TLR2, and TLR4 protein in lung tissue was detected by Western blotting. The mRNA expression of TLR2 and TLR4 in lung tissue of mice was detected by RT-PCR. Results Compared with the asthma model group, the numbers of neutrophil, lymphocyte and eosinophil in the alveolar lavage fluid of mice treated with honokiol 50 μg/kg group were significantly reduced (P < 0.01); Lung pathology was significantly improved, and inflammatory cell infiltration was significantly reduced (P < 0.05). The tracheal wall and alveolar damage were significantly relieved; The expression levels of PI3K, Akt, p-Akt, TLR2, TLR4 protein and TLR2, TLR4 mRNA were significantly down-regulated in lung tissue (P < 0.05). Conclusion Honokiol has a good inhibitory effect on OVA-induced inflammatory response in asthmatic mice. The mechanism may be related to the inhibition of PI3K/Akt signaling pathway by TLR2 and TLR4 receptors.