Caulis Lonicerae Japonicae extract shows protective effect on osteoporosis in rats

Purpose: To investigate the effect of Caulis lonicerae Japonicae extract (CLJE) on ovariectomyinduced osteoporosis in rats.
Methods: Female Sprague-Dawley rats were randomly assigned to a control group (normal rats) and five ovariectomy (OVX) subgroups: OVX with vehicle (OVX), OVX with 17ß-estradiol (E2, 25μg/kg/day), and OVX with CLJE doses (150, 300, and 600 mg/kg/day). Daily oral administration of E2 or CLJE started 4 weeks after OVX and lasted for 16 weeks. The bone mineral density (BMD) of L4 vertebrae and right femurs was determined. The length of each femur was measured with a micrometer, and the center of the diaphysis was determined. Three representative L4 vertebrae were selected to evaluate trabecular microarchitecture. Serum alkaline phosphatase (ALP), urinary calcium (U-Ca), urinary phosphorus (U-P), urinary creatinine (Cr) and osteocalcin (OC) levels were measured using a diagnostic reagent kit.
Result: The results show that a high-dose of CLJE (600 mg/kg) significantly inhibited bone mineral density (BMD) reduction of L4 vertebrae (0.24 ± 0.02, p < 0.05) and femur (0.24 ± 0.03, p < 0.05) caused by OVX, and prevented the deterioration of trabecular microarchitecture (p < 0.05). High-dose CLJE also improved morphometric parameters, viz, trabecular number (Tb-N) (4.6 ± 0.3, p < 0.05), trabecular thickness (Tb-Th, 0.084 ± 0.012, p < 0.05) and trabecular separation (Tb-Sp, 0.14 ± 0.02, p < 0.05) in L4 vertebrae significantly.
Conclusion: The results indicate that CLJE prevents OVX-induced osteoporosis in rats. Thus, CLJE is a potential natural alternative for the treatment of postmenopausal osteoporosis in future.

Keywords
Caulis Lonicerae Japonicae; Post-menopausal osteoporosis; Ovariectomy; Bone mineral density; Trabecular microarchitecture; Diaphysis