RÉSUMÉ
Recent studies have shown that TCM treatment for bone metabolic diseases, such as steroid-induced avascular necrosis of the femoral head, has definite efficacy and has received extensive attention. However, due to lack of molecular biological basis of pharmacodynamics mechanism, it has not yet reached the standard of scientific treatment. The discovery of OPG/RANK/RANKL system has become a new breakthrough point in the prevention and treatment of bone metabolic diseases. The pathogenesis of deficiency of spleen and kidney - blood stasis - caused by phlegm arthralgia caused by blood stasis is closely related to the system. The effect of the final control of the system from the deficiency theory can be expressed through the axial micro-information. This article discussed the TCM syndrome differentiation of steroid-induced osteonecrosis of the femoral head and the relation of regulation of bone metabolism combined with the OPG/RANK/RANKL system, and provided the basis for prevention and treatment of this disease.
RÉSUMÉ
Objective The study was carried out to investigate the effects of different dietary Ca levels on bone metabolism, based on the osteoprotegerin ( OPG)-receptor activator of NF?κB ligand ( RANKL)?receptor activator of NF?κB ( RANK) system in growing WHBE rabbits. Methods Twenty one weaned male WHBE rabbits at the age of 42 days were divided into 3 groups (I, II and III) according to dietary Ca levels (0. 95%, 1. 10%, and 1. 30%, respectively) for a 42?d feeding trial. The above three diets had similar phosphor (P) (about 0. 64 g/kg), digestible energy (9. 50 MJ/kg), crude protein (about 19. 70%) and crude fibre (13. 57%) contents. When the feeding trial finished, the serum in?dices of bone metabolism (Ca, PTH and BALP) were detected, and the OPG?RANK?RANKL system in bone tissue was analyzed by real?time fluorescence quantitative PCR assay and immunohistochemistry, respectively. At last, the relationships between bone metabolism and dietary Ca were evaluated according to RANKL/OPG ratio. Results All the contents of serum Ca, PTH and BALP had no significant differences in the groups I, II and III (P>0. 05). Both the RANKL mR?NA and RANKL/OPG mRNA ratio were lowest in the group II and had significant differences with group I and III ( P<0. 05). Dietary Ca levels had significant effects on the protein expression of OPG?RANK?RANKL in bone tissues (P<0. 01). The positive index of OPG in the groups II and III was significantly higher than that in the group I(P<0. 01), while the positive index of RANK in the group II was lower than those of the group I and III(P<0. 01). The protein ex?pression positive index ratio of RANKL to OPG was also lowest in the group II, showing a significant difference with group I(P<0. 01). Furthermore, both the gene transcription ratio of RANKL to OPG and the protein expression positive index ratio of RANKL to OPG had significant correlations (with quadratic curve) to the dietary Ca levels (R2 =0. 4068, 0. 8433;P<0. 05,P<0. 001). Conclusions In summary, the bone metabolism of WHBE rabbits during growing periods has sig?nificant correlation with dietary Ca levels. An optimal bone metabolism status can be obtain at 1. 10% dietary Ca level as demonstrated in this study.
RÉSUMÉ
Objective To comparatively investigate the characteristics of bone metabolism in forelimb malformation WHBE rabbits based on the OPG/RANK/RANKL system.Methods Healthy male 2-2.5-month old WHBE rabbit ( HWR) , Healthy Japanese rabbit ( HJR) and forelimb malformation WHBE rabbit ( FMWR) were used in this study and divided into 3 groups, HWR, HJR and FMWR groups, with 10 rabbits in each group.The shape of forelimb and mean gray value observed from X-ray film were examined, and the bone tissue micro-morphology was analyzed using HE staining.Re-al-time fluorescence quantitative PCR was used to determine the expression of osteoprotegerin ( OPG) and receptor activator of NF-KB ligand ( RANKL) mRNA.The expressions of OPG, receptor activator of NF-KB ( RANK) and RANKL protein in serum and bone tissue were assayed by enzyme-linked immunoassay ( ELISA) and immunohistochemistry, respectively. Results Compared with the HWR and HJR groups, rabbits in the FMWR group appeared abnormal in toutuous forelimb and thinner bone cortex.The mean gray values of X-ray in the FMWR group were lower than that in the HWR group ( P<0.05).There were significant differences between the FMWR and healthy rabbits (HWR and HJR) in the following pa-rameters:RANKL mRNA expression and RANKL/OPG mRNA ratio in the liver(P<0.05, P<0.01), serum protein expression of RANK and RANKL and RANKL/OPG ratio (P<0.05, P<0.01), and positive index of expression of RANKL protein and RANKL/OPG ratio in the bone tissue(P<0.05, P<0.01).Furthermore, the gene expression lev-els of OPG and RANKL of HWR were significantly higher than that of HJR(P<0.05, P<0.01).Conclusions The FMWR show some abnormal symptoms in bone metabolism as well as decrease of bone quality and histological changes of bone micro-structure, due to the significant increase of RANKL/OPG ratio of FMWR.The breed differences between WHBE and Japanese rabbits in RANKL mRNA expression level may be one of factors inducing limb malformation in the WHBE rabbits.