Objective To explore the mechanism of
Epimedium brevicornum (EB) on aseptic loosenin of prothetic hip joint by studying its
effects on secretion of TNF-α and expression of TACE-mRNA in human monocytes induced by PMMA cement particles. Methods Blood samples (14 ml each) taken from 21 fracture patients (with no
prothetic joint implanted), were processed to get the mononuclear cells (MNLC) to perform the experiments in two big groups. GroupⅠ, to test the effect of EB on the secretion of TNF-α, was divided into 5 subgroups: No. 1, culture of MNLC only; No. 2, MNLC + PMMA (cement particles suspended in culture medium RPMI/1640); Nos. 3, 4, 5, MNLC + EB (5 mg/kg, 10 mg/kg, 20 mg/kg respectively). GroupⅡ, to test the effect on the expression of TACE mRNA, was divided into 3 subgroups: No.1, MNLC + PMMA + PMA; No. 2, MNLC + RPMI/1640; No. 3, MNLC + PMMA + EB (20 mg/L). Each group was incubated for 48 hours before the level of TNF and the expression of TACE mRNA were determined. Results The leve of TNF was much higher in subgroup No. 2 than in the others ( Nos. 1, 3,4,5, P<0.01), but there were no significant differences in TNF between the subgroups Nos. 3, 4, 5 (P>0.05). The expression of TACE mRNA was increased significantly when PMMA particles was added in subgroup No. 1, as compared with that in No. 2, where only RPMI/1640 was present; while the expression of TACE mRNA was decreased significantly by EB in No. 3. Conclusion PMMA particles can stimulate MNLC to secrete TNF, while EB downregulates the expression of TACE mRNA, inhibiting the secretion of TNF and the associated bone resorption and loosening of prothesis. The present experiment demonstrates
Epimedium brevicornum may clinically contribute to the prevention and treatment of aseptic loosening of prothesis.