Anti-bone Resorption And Anti-inflammatory Effects Of Active Constituent From Litsea Cubeba (Lour.) Pers Root And Its Synthetic Analogues

Bone resorption can degrade bone minerals and organic matrix,it can occur in various parts of the skeletal system,and physiological bone resorption can maintain the growth and metabolic balance of the body’s bones.Pathological bone resorption can lead to bone loss,bone microstructure disorder,and increased bone fragility;it can also cause uneven bone surface.Inflammation can cause joint pain,swelling,and mobility problems.In most bone diseases,symptoms of decreased bone density and inflammation,such as ankylosing spondylitis,rheumatoid arthritis and senile osteoarthritis,are displayed at the same time.Litsea cubeba(Lour.)Pers.belongs to genus Litsea(Lauraceae),it is commonly used to treat rheumatism and relieve pain in folk formulas,clinically,it is also used for bone injury,cerebral thrombosis and other diseases.The previous research found that dibenzylbutane-type lignan LCA in the extract of Litsea cubeba(Lour.)Pers.was the main active ingredient,it achieves anti-inflammatory effects by acting on the NF-κB pathway,and these studies suggest that LCA may have potential for further research and development of new drugs for RA.Natural chemical product LCA can be chemically synthesized to obtain,It’s 9,9’-O-di-(E)-feruloyl-meso-5,5’-dimethoxysecoisolariciresinol(LCAs: distinction with the previous study drug names),and we speculates that the skeleton of dibenzylbutane-type lignin is closely related to the anti-inflammatory activity of LCAs,however,its anti-inflammatory effect less than expected,it is necessary to further modify the chemical site of LCA,and got its derivatives.The specific research on anti-bone resorption and anti-inflammatory effects of LCAs and its derivatives is as follows:1.Research on LCAs and its derivatives on bone destruction1.1 Effect of LCA on the knee joint in Freund’s complete adjuvant induced arthritisThrough the treatment of the knee joint retained in the previous AA rat experiment,the HE data were analyzed,then evaluate the knee joint morphology.Experimental results show that LCA can significantly ameliorate joint destruction and bone damage,reduce the infiltration of inflammatory cells and the hyperplasia of synovial tissue,increase the bone density,and showed a dose-dependent manner.The effect of high dose LCA on osteoarthritis is similar to methotrexate,which shows the efficacy of relieving osteoarthritis at the individual level.Consistent with the results of the previous research group: LCA can improve the swelling of the rats’ feet,protect the spleen and thymus of the rats,and reduce the levels of IL-1β,IL-6 in the serum of the rats,and achieve the effect of inhibiting rheumatoid arthritis.In conclusion,LCA has the pharmacological effects of anti-inflammatory,inhibition of bone loss and synovial hyperplasia.1.2 Investigation of effect and mechanism of LCAs and its derivatives on RANKL-induced osteoclastsThe RANKL-induced osteoclasts were used to investigate the anti-bone destruction effect and the mechanism of LCAs and its derivatives.It can reduce the number and size of osteoclasts,and inhibit the expression of TRAP activity and the formation of actin ring of osteoclasts in a dose-dependent manner,the derivative W-1-27 can also inhibit the formation and differentiation of osteoclasts.LCAs could significantly inhibit the expression of p-ERK,p-JNK,p-p65 and p-p38,thus effectively downregulated the effection of osteoclastrelated proteis,such as c-Fos,NFATc1 and MMP-9 as shown by Western blot,thereby inhibit osteoclast differentiation and inhibit osteoclast bone resorption.2 Anti-inflammatory effects and mechanisms of LCAs and its derivativesLPS-induced RAW264.7 cells were used to study the anti-inflammatory effect and mechanism of dibenzylbutane lignin LCAs and its analogs.Comparing the anti-inflammatory activity data of LCAs,it can be found that compounds W-1-28 and W-1-32 can more effectively inhibit RAW264.7 cells from releasing the inflammatory mediator NO,W-1-28 and W-1-32 inhibited the IL-1β,IL-6 and TNF-α mRNA expression,and show anti-inflammatory via inhibited IKKα/β,IκBα and p65 phosphorylation.Through structural analysis,it was found that when the derivatives W-1-28 and W-1-32 changed the ester bond in the compound LCA to an amide bond,and introduced the trifluoromethylphenylpiperazinyl and 2,3-dimethylpiperazine group side chains,The compounds have higher anti-inflammatory activity than LCAs.3 Preliminary exploration of chemical composition of Litsea cubeba(Lour.)Pers.from different regions.Qualitative analysis was performed by extracting extracts from Litsea cubeba(Lour.)Pers from different places by HPLC-MS,and matched the experimental results with the database of the genus Litsea compounds constructed by consulting the literature,and found that 51 compounds overlapped.Comparing the compounds contained in Litsea cubeba(Lour.)Pers from nine places,it was found that the types of compounds contained in different places were not the same,The main research object of this subject is LCA,which can be found in Fujian,Guangdong,Guangxi,Guizhou,Hainan,Jiangsu,Yunnan and Zhejiang,except Anhui province,However,the content of LCA in plants is not high.It is recommended to use chemical synthesis to reduce the extraction cost.At the same time,it is pointed out that the six compounds with the highest response in the map of labeled total compounds.These data can provide a basis for the formulation of future quality standards for medicinal materials.