Development of 3-mercaptopropyltrimethoxysilane(MPTS)-modified bone marrow mononuclear cell membrane chromatography for screening anti-osteoporosis components from Scutellariae Radix

Osteoporosis is a bone metabolic disease caused by the imbalance between osteoblasts and osteoclasts due to excess osteoclastogenesis,manifesting in the decrease of bone density and bone strength.Scutellariae Radix shows good anti-osteoporosis activity,but the effective component is still unclear.Cell membrane chromatography(CMC) is a biological affinity chromatography with membrane immobilized on a silica carrier as the stationary phase.It can realize a dynamical simulation of interactions between drugs and receptors on cell membrane,which is suitable for screening active compounds from complex systems.In this study,the components of Scutellariae Radix with potential anti-osteoporosis activity through inhibiting the differentiation from bone marrow mononuclear cells(BMMCs) to osteoclast were screened by a BMMC/CMC analytical system.Firstly,a new3-mercaptopropyltrimethoxysilane(MPTS)-modified BMMC/CMC stationary phase was developed to realize covalent binding with cell membrane fractions.By investigating the retention time(~tR) of the positive drug,the life span of the MPTS-modified CMC columns was significantly improved from 3 to 12 days.Secondly,6 components of Scutellariae Radix were screened to show affinity to membrane receptors on BMMCs by a two-dimensional BMMC/CMC-TOFMS analytical system.Among them,tectochrysin demonstrated the best anti-osteoporosis effect in vitro,which has never been reported.We found that tectochrysin could inhibit the differentiation of BMMCs into osteoclasts induced by receptor activator of nuclear factor-κB ligand(RANKL) and macrophage colony-stimulating factor(M-CSF) in a concentration-dependent manner in vitro.In vivo,it significantly reduced the loss of bone trabeculae in ovariectomized mice,and decreased the level of C-terminal cross-linking telopeptides of type 1 collagen(CTX-1),tartrate-resistant acid phosphatase 5 b(TRAP-5 b),interleukin 6(IL-6) in serum.In conclusion,tectochrysin serves as a potential candidate in the treatment of osteoporosis.The proposed twodimensional MPTS-modified BMMC/CMC-TOFMS analytical system shows the advantages of longlife span and fast recognition ability,which is very suitable for infrequent cell lines.