Abstract
BackgroundAsthma is a chronic inflammatory disease characterized by airway remodeling and inflammation. Rhynchophylline is a kind of indole alkaloid isolated from Uncaria rhynchophylla. Here we investigated the effect of rhynchophylline on autophagy in asthma.MethodsA mice model of asthma was established by ovalbumin challenge. Histopathological changes were assessed by hematoxylin-eosin staining, periodic acid-schiff staining and Masson staining. The levels of IgE in serum, interleukin-6 and interleukin-13 in bronchoalveolar lavage fluid, as well as the activities of superoxide dismutase and catalase in lung tissues were detected. The expression of autophagy-related genes and Janus kinase (JAK) 2/ signal transducer and activator of transcription (STAT) 3 signal was detected by western blot and immunofluorescence. Airway smooth muscle cells (ASMCs) were isolated, and the effect rhynchophylline on autophagy in ASMCs was explored.ResultsOur data showed that rhynchophylline treatment alleviated inflammation, airway remodeling, and oxidative stress in asthma. In addition, autophagy, which was implicated in asthma, was suppressed by rhynchophylline with decreased level of autophagy-related proteins. Furthermore, rhynchophylline suppressed the JAK2/STAT3 signaling pathway, which was activated in asthma. In vitro study showed that rhynchophylline suppressed ASMC autophagy through suppressing the activation of JAK2/STAT3 signal.ConclusionsOur study demonstrated that rhynchophylline can alleviate asthma through suppressing autophagy in asthma, and that JAK2/STAT3 signal was involved in this effect of rhynchophylline. This study indicates that rhynchophylline may become a promising drug for the treatment of asthma.
Highlights
Asthma is a chronic inflammatory disease characterized by airway remodeling and inflammation
Primary antibodies against light chain 3 (LC3), ATG5, p62, Janus kinase (JAK) 2, p-JAK2 and STAT3 were obtained from Abclonal (Wuhan, China)
These results suggested that Rhy inhibited the activation of JAK2/STAT3 signaling pathway in asthmatic mice
Summary
Materials Ovalbumin (OVA) was obtained from Sigma (St.Louis, MO, USA). Rhynchophylline was obtained from Melonepharma (Dalian, China) or Aladdin (Shanghai, China). Primary antibodies against LC3, ATG5, p62, Janus kinase (JAK) 2, p-JAK2 and STAT3 were obtained from Abclonal (Wuhan, China). Cy3-labelled and fluorescein isothiocyanate (FITC)-labeled secondary antibodies were obtained from Beyotime (Shanghai, China). The membranes were incubated with primary antibodies: Immunofluorescence After deparaffination and rehydration, the slices of lung tissues from each group were washed in PBS and restored in antigen retrieval solution. The slices were blocked with goat serum (Solarbio, Beijing, China) and incubated with primary antibodies: beclin-1 (1: 50) or STAT3 (1: 100) at 4 °C overnight. The slices were incubated with Cy3-labelled or FITC-labeled secondary antibodies (1: 200) at room temperature for 60 min, following by washing with PBS. The cells were stained with MDC (KeyGen, Nanjing, China) at room temperature for 15 min.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
