Tubson-2 decoction ameliorates rheumatoid arthritis complicated with osteoporosis in CIA rats involving isochlorogenic acid A regulating IL-17/MAPK pathway.

BACKGROUND: Osteoporosis (OP) is considered as one of the major comorbidities of rheumatoid arthritis (RA), and is responsible for fragility fracture. However, there is currently no effective treatment for RA complicated with OP. Tubson-2 decoction (TBD), a Mongolian medicine also known as Erwei Duzhong Decoction, has been shown to exert a preventive effect on post-menopausal osteoporosis (PMOP). The preventive effects of TBD on RA-induced OP, as well as the bioactive compound responsible and the underlying mechanisms, remain to be elucidated. OBJECTIVE: To explore the effects of TBD on RA-induced OP in vivo, and to elucidate the mechanism of isochlorogenic acid A (ICA), the effective component of TBD, in vitro. METHODS: To evaluate the anti-arthritic and anti-osteoporotic effects of TBD, we conducted H&E straining and safranine O/fast green, TEM, immunohistochemistry (IHC), bone histomorphometry, micro-CT imaging, and biomechanical testing in collagen induced arthritis (CIA) rats. The active ingredient in TBD was identified using network pharmacology and molecular docking. The identification was supported by in vivo IHC assay, and further confirmed using qRT-PCR, Western blot, and SEM analysis in TNF-α-treated MH7A cells and/or in LPS-exposed RAW264.7 cells. RESULTS: Oral administration of TBD attenuated the severity of arthritis and osteopenia as well as poor bone quality, in CIA rats. Additionally, TBD and the positive control, tripterygium glycosides (TG), exhibited similar effects in reducing inflammation in both the synovium and ankle joint. They also were both effective in improving bone loss, microarchitecture, and overall bone quality. TBD reduced the expression of MMP13, IL-17, and p-JNK protein in the synovium of CIA rats. ICA, which was screened, suppressed TNF-α or LPS-triggered inflammatory responses via down-regulating IL-17 signaling, involving in MMP13, IL-1ß, IL-23, and IL-17, and the MAPK pathway including p-ERK, p-JNK, and p-P38, both in MH7A cells and in RAW264.7 cells. Furthermore, ICA prevented osteoclasts from differentiating and bone resoprtion in a dose-dependent manner in vitro. CONCLUSION: This study provides the first evidence that TBD exerts intervening effects on RA-induced OP, possibly through the downregulation of the IL-17/MAPK signaling pathway by ICA. The findings of our study provides valuable insights for further research in this area.

Effect of intranasal acupuncture on the pathology of nasal mucosa in rabbits with allergic rhinitis and related regulatory mechanism of transient receptor potential vanillic acid receptor 1-substance P axis / 解剖学报

Objective To investigate the pathological changes of nasal mucosa by intranasal acupuncture, and to explore the possible signal transduction mechanism through the distribution and expression of transient receptor potential vanillic acid receptor 1 (TRPV1)-substance P (SP) axis in nasal mucosa of experimental allergic rhinitis. Methods An animal model of allergic rhinitis was constructed by ovalbumin and aluminium hydroxide gel treatment. Twenty five New Zealand rabbits were randomly divided into normal group, model group, sham acupuncture group, acupuncture Wai Ying Xiang group and intranasal acupuncture group, with 5 rabbits in each group. To observe the effect of intranasal acupuncture on animal behavior, nasal mucosa pathology, eosinophils (EOS) count and IgE content in arterial blood. In addition, HE staining was used to determine the distribution of EOS in nasal mucosa and immunohistochemistry was used to observe the distribution and expression of TRPV1 and SP in nasal mucosa membrane. Results Compared with the model group, the behavioral score of the sham acupuncture group did not decrease significantly, while the behavioral score of the Wai Ying Xiang acupuncture group and the intranasal acupuncture group showed a downward trend, and the decrease degree of the intranasal acupuncture group was more significant. Compared with the normal group, the eosinophil count in the model group increased slightly (P0.05). HE staining found that eosinophilic distribution increased significantly in the model group and the sham acupuncture group compared with the normal group, and the difference was statistically significant (P<0.05). Compared with the model group, the distribution of eosinophil reduced in the nasal acupuncture group and the Wai Ying Xiang group. The difference was statistically significant (P<0.05 ). Immunohistochemical found that TRPV1 and SP expressed significantly in the nasal mucosa of the model group and the sham acupuncture group compared with the normal group, the difference was statistically significant (P<0.05). Compared with the model group, TRPV1 and SP expression decreased significantly in the intranasal acupuncture group and the external yingxiang group, the difference was statistically significant (P<0.05). Conclusion Intranasal acupuncture can alleviate the nasal symptoms of allergic rhinitis model by reducing the Chemotaxis of eosinophils in nasal mucosa and the content of IgE in serum.