Study On The Effect Of Low Toxicity Essential Oil Of Asarum And Interaction Mechanisms On Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is an extremely harmful autoimmune disease. The victims'joints are swollen, painful and hardly to move in the morning in initial stage. Then their joints become tetany, malformationm and articular dyskinesia. Moreover, RA even induces diseases of heart, kidney, lung, nervous system and blood system of victims. To now, the cause, pathogeny and mechanism are not very clear, but TNF-αand IL-1 are widely considered as the important factors causing this disease.Asarum is widely used in clinic, such as expelling the wind cold, promoting the restoration consciousness, stopping the pain and etc. Study shows that essential oil is the mainly effective composition of Asarum, which has analgesic and anti-inflammatory effects. Safrol is a component of essential oil which has high toxicity. We used reduced pressure distillation method to separate Safrol from essential oil, and study the relationship between dosage and effect.The acute toxicity test showed that the toxicity of essential oil (LD50 was 2.33ml/kg) was lower than original one(1.77ml/kg). Some mice were dead, and intoxicating phenomenon mainly appeared as unusual roaring, bradypsychia, glazed looking, slow moving, difficult breathing, and 2 of mice which ig original essential oil had edeoptosis and abdominal flatulence.We used hot plate test and writhing test to understand the analgesic effects of low toxicity essential oil, and used adjuvant-induced arthritis model to study the anti-inflammatory effects. The results showed that low toxicity essential oil can significantly suppress reactions of high position of nerve centre and pain caused by chemical compound. Low and middle doses low toxicity essential oil can only suppress adjuvant-induced arthritis primary disease in 18h after inject Freud's complete adjuvant (FCA) and its effect decreased quickly. However, high dose low toxicity essential oil inhibited swollen foot for a long time. To adjuvant-induced arthritis secondary disease, three doses had extremely effects to suppress rats'swollen feet and general symptoms.Through measuring the contents of TNF-a and IL-1 of serum, we found the contents were lower than model group. Meanwhile, pathological sections showed three doses group can significantly suppress synovium proliferation and decrease amount of inflammatory cells, compared to the model group. We think low toxicity essential oil might work through reducing amount of inflammatory cells which secreted TNF-a and IL-1.