Anti-rheumatoid Arthritis And Chemical Constituents Of Caragana Pruinosa Kom

Rheumatoid arthritis (RA) is a kind of systemically chronic and autoimmune diseases with joint synovitis and extensive inflammation of connective tissues (serosa, eye, skin, heart, lung and blood vessels) as the main manifestation. The pathogenesis of RA is not very clear and its main feature is the destruction of cartilage and bone tissue, which finally led to disability and seriously affected the patients’ life quality. RA generally requires long treatment time and high medical expense, which brought a heavy financial burden and mental suffering the patients. There is no excellent cure method for RA, and the current treatments mainly involve surgery, chemotherapy and biologic therapy. Usually, surgical treatment also causes damage to the body and the cost is expensive. Long-term drug treatment is easy to produce adverse reactions and sometimes serious side effects. Biological agents often interfere with normal cells while killing abnormal ones. Therefore, searching for highly effective anti-RA drugs with low toxicity remains a difficult task.Anti-RA drugs derived from Traditional Chinese Medicine possess both diversity in chemical structure and mechanisms of action. Traditional medicines of Minorities constitute an important part of Traditional Chinese Medicine, which is a wealth of practical experience and unique theoretical basis. Uighur medicine is one of the four ethnic minority medicine (Tibetan, Mongolian, Uygur, Dai) in China, which advocats external treatment for internal diseases and internal treatment for external diseases. Combination of internal and external treatment in Uighur medicine makes it a good choice for the prevention and control of chronic diseases. Xinjiang belongs to arid and semi-arid inland areas with large temperature difference between day and night. This climate variation can extremely cause RA. However, prevalence rate of rheumatism diseases in Xinjiang area is not high. The reason lies in the formation of Uygur medicine system for preventing and treating rheumatism diseases.In view of this, based on literature search and resources survey, we selected 40 Xinjiang medicinal plants with traditional use against rheumatism diseases for anti-RA activity screening. Caragana pruinosa Kom, belongs to the Leguminosae family and the Caragana genus, was found to possess excellent anti-RA activity. C. pruinosa was widely used for the treatment of RA in folk. However, its chemical components and pharmacological effects have not been reported yet. Therefore, our studies were performed to investigate the anti-RA activity and chemical components of C. pruinosa, in order to lay the foundation for the further utilization and development of C. pruinosa. Our work mainly deals with the following contents:1. Study on the in vivo anti-RA activity of C. pruinosaThe collagen type II-induced RA rat model was used to investigate the anti-RA activity of the 80% ethanol extract of C. pruinosa roots. The results showed that the ethanol extract of C. pruinosa can significantly reduce arthritis index and inhibit swelling degree of joints. The ethanol extract of C. pruinosa roots can also decrease the levels of interleukin 1β (IL-1β), interleukin 6 (IL-6), tumor necrosis factor (TNF-a) and C reactive protein in rat serum, and increase the level of interleukin 10 (IL-10). The results of histopathological studies revealed that C. pruinosa roots extract significantly decreased synovial hyperplasia and inflammatory cells infiltration. Our study showed that C. pruinosa possessed good anti-RA activity.2. Studies on chemical constituents from C. pruinosaModern chromatographic and spectroscopic techniques (NMR, MS, IR, etc) were exployed to clarify the chemical compositions of C. pruinosa root, which led to the isolation and identification of 14 flavonoid compounds, including 6 new compounds (including a novel isoflavone possessing spiro-heterocycle moiety) and 2 new natural compounds. Other compounds were all isolated from the genus Caragana for the first time. Pharmacological studies have shown that Caragana. pruinosa have isopropenylbenzene and furan flavonoids fragment which has a good anti-inflammatory activity, significantly inhibited LPS-induced NO production in RAW264.7 cells. It is suggested that the flavonoid ingredient is the main active substance of anti-RA of the Caragana. pruinosa.3. Total flavonoid contents determination and chemical analysis of different part of C. pruinosaIn view that the chemical compounds isolated form C. pruinosa were all flavonoids, we speculated that C. pruinosa possessed abundant flavonoids. Therefore, the content of total flavonoids in different medicinal parts (roots, stems and seeds) of C. pruinosa was determined by ultraviolet spectrophotometry. The results showed that the content of total flavonoids in roots was 0.90 mg/g, higher than that in stems (0.24 mg/g) and seeds (0.87 mg/g). Further research found that the flavonoids of roots mainly concentrate in the ethyl acetate fraction (2.53 mg/g).The overall chemical profiles of seeds and roots were found to be similar through HPLC comparison of the roots, stems and seeds of C. pruinosa. Further utilization of LC-MS technology combined with our established chemistry database of the genus Caragana, we confirmed 81 known compounds from the roots,76 known compounds from the stems,70 known compounds from the seeds, most of which are flavonoids. Among them,47 compounds were shared by the roots and stems, whereas 45 compounds were shared by the roots and seeds. Three medicinal parts showed some similarity in chemical profile. The traditionally used medicinal partS of C. pruinosa were roots. Excessive exploitation will inevitably cause environmental and ecological damage. Our results showed that stems and seeds possess the potential as alternative medicine for roots.In conclusion, our study unambiguously confirmed that C. pruinosa possesses good anti-RA activity. Flavonoids are the anti-RA activity of those bioactive compounds. Stems and seeds possessed the potential as alternative medicine for roots on the basis of total flavonoids content determination and comparative chemical analysis. Our study can lay the foundation for the further utilization and development of the medicinal resource of C. pruinosa.