Objective: To explore the specific mechanism of heat-reinforcing needling (HRN) for rheumatoid arthritis (RA) rabbits with cold syndrome based on metabolomics.
Methods: A total of 40 healthy rabbits were randomly divided into a normal group, a model group, a reinforcing-reducing needling(RRN) group, a twirling-reinforcing needling (TRN) group and a HRN group (n=8 rabbits/group). The RA model with cold syndrome was established with ovalbumin and freezing. Except the normal and model groups, RRN, TRN and HRN were given at "Zusanli" (ST 36) in the corresponding acupuncture groups for 30 min, once a day for 7 days. After the interventions, the pain threshold and the local skin temperature of each group were observed. The endogenous metabolites in the serum were analyzed by the gas chromatography mass spectrometry (GC-MS) technology combined with the pattern-recognition method.
Results: The pain threshold and the local skin temperature in the model group were lower than those in the normal group (P<0.05). The pain thresholds and the local skin temperatures in the three acupuncture groups were higher than those in the model group after interventions (P<0.05), and those in the HRN group were obviously higher than those in the RRN and TRN groups (P<0.05). The serum metabolites of leucine, valine, isoleucine, and arachidonic acid in the model group were increased compared with those in the normal group (P<0.05), and the metabolites of α-ketoglutaric acid, citric acid, succinic acid, glucose, inositol, palmitic acid, stearic acid, lactose, d-ribose, and D-mannose were decreased (P<0.05). The above-mentioned metabolites in the three acupuncture groups were significantly reversed relevant to the model group (P<0.05), and the effect of HRN group was significantly superior to those of the RRN and TRN groups in regulating α-ketoglutaric acid, citric acid, succinic acid, glucose, inositol, d-ribose, and D-mannose (P<0.05).
Conclusions: HRN for RA with cold syndrome is effective, which may be related to the specific regulation for the krebs cycle and glycometabolism.