[Mechanism of regulation of CNP rat model by oxalis decoction via cGAS-STING signaling pathway].

Objective: To investigate the therapeutic mechanism of oxalis decoction on CNP rats by regulating cGAS-STING signaling pathway.

Methods: Thirty specific pathogen-free SD male rats were randomly divided into normal control group (NC), model control group (MC), and oxalis decoction group (OD),with 10 rats in each group.The left and right anterior abdominal lobes of each group were surgically exposed.The normal control group was injected by the same volume of normal saline.After the model was successfully established,the OD group was given ［9.37g/(kg·d)］ by gavage once a day, and the NC and MC groups were given ［0.01/(mｌ/g)］ normal saline by gavage. From the 7th day of administration, the body weight of the rats in each group was recorded every 7 days for dynamic comparison. After 50 days of administration, the prostate index of the rats in each group was calculated, the morphological and pathological changes of the prostate tissue were observed by HE staining,and the expression levels of tumor necrosis factorα(TNF-α), interleukin-1β(IL-1β)and IL-6 in serum were detected by ELISA. RT-qPCR was used to detect the mRNA expression of cGAS, STING, TRAF6 and HSP70 in prostate tissue of rats in each group.

Results: Versus the NC group and OD group, the prostate organ index in MC group was significantly higher than that in other groups (P<0.01). Versus the NC group, the HE staining results of the MC group showed that the prostate gland structure was disordered, and the interstitial and acinar epithelium were extensively edema, accompanied by a large number of lymphocyte infiltration, cell swelling, loose cytoplasm, and a small number of foam cells. Versus the MC group, HE staining showed that the edema of interstitial and acinar epithelial cells in the rat prostate tissue was reduced after the OD group intervention, and the inflammatory cell infiltration in the interstitium was significantly reduced.Versus to NC group, the expression levels of TNF-α,IL-1βandIL-6 in MC group were significantly increased（P<0.01 ).Versus to MC group,the expression levels of TNF-α, IL-1β and IL-6 in OD group were decreased (P<0.05). Versus the NC group, the mRNA expression of cGAS, STING and TRAF6 in the MC group was significantly up-regulated,and HSP70mRNA was significantly down-regulated(P<0.01).Versus the MC group,the OD group had significantly decreased mRNA expression of cGAS, STING and TRAF6 and significantly increased mrna expression of HSP70(P<0.05).

Conclusions: CNP has autoimmune disorders that cause inflammatory responses.The key target for CNP treatment is to regulate innate immunity.The treatment with oxalis decoction can significantly improve the prostate organ index and pathological changes in CNP rats, which may be related to the down-regulation of cGAS-STING innate immune signaling pathway and the inhibition of inflammatory mediators secretion.