Anti-inflammatory effect of extracts of Dendropanax dentige and Lycopodiastrum casuarinoides on rheumatoid arthritis and their underlying mechanism in rats

OBJECTIVE To investigate the anit-inflammatory effect of extracts of Dendropanax dentiger(Harms)Merr and Lycopodiastrum casuarinoides(Spring)Holub on rheumatoid arthritis(RA)using adjuvant arthritis(AA)rat model and possible mechanisms.METHODS The AA rat model of RA was induced in adult SparagueDawley(SD)rats by injecting of the adjuvant at base oftail.One-week-old male SD rats were randomly divided into the following groups:normal saline group(blank control),D.dentiger decoction group(80g·kg-1·d-1),L.Casuarinoides decoction group(80 g·kg·d-1),the total of glucoside Tripterygium(GTT)group(positive control,2 mg·kg-1·d-1).They were administered orally for 6weeks.Histopathology of tissues arthritis rats was observed by H.E staining.The volume of paw swelling was measured and the arthritis inflammation index was calculated.The expressions of tumor necrosis factor-α(TNF-α)and interlukin-1β(IL-1β)were detected by the ELISA assay.In addition,previous study has reported that plant-derived mi RNAs play a role for cross kingdom regulatory potential.Thus,we also performed RNA-seq technique to identify bioactive mi RNAs via comparative transcriptome analysis between D.dentiger and L.Casuarinoides.RESULTS Comparing with AA model group,the volume of paw swelling and the arthritis index were increased significantly in the AA rat model group(P<0.01),suggesting that the AA model rats were prepared properly.Compared with the AA model group,the volume of paw swelling of D.dentiger decoction group,L.Casuarinoides decoction group was decreased by 25.2%and 10.3%,respectively,and the arthritis index was decreased by 27.2%and 18.3%,respectively.Compared with AA model group,TNF-αprotein expression of D.dentiger decoction group and L.Casuarinoides decoction groups were decreased by 16.3%and 14.7%,and IL-1βprotein expression was decreased by 23.6%,18.9%(P<0.05,P<0.01),respectively.Besides,we found that some plant-derived homologous mi RNAs(such as mi RNA192 and mi RNA30a)associated with cell apoptosis processing have been screened out via comparative transcriptome analysis.But the underlying mechanisms about two mi RNAs function needs much more investigate.CONCLUSION Results showed significant anti-inflammatory effect of aqueous extracts of D.dentiger and L.Cauarinoides and justifying their therapeutic role in inflammatory condition.Furthermore,anti-inflammatory effect of D.dentiger and L.Cauarinoides may be attribute to the herb-derived mi RNAs cross-kingdom regulation.