ABSTRACT
Juvenile zebrafish were used to screen the active components of Lycii Fructus for improving osteoporosis. The screening results were further verified by zebrafish adult osteoporosis model and the action mechanism was explored. Prednisolone was used as the inducer to build osteoporosis models of juvenile and adult zebrafish, and 9 groups of samples of different extracts and chemical parts of Lycii Fructus were given. Alizarin red staining was applied for observing the scale matrix mineralization and bone resorption. The activities of osteoblasts and osteoclasts were detected using alkaline phosphatase (ALP) and tartrate resistant acid phosphatase (TRAP/TRACP) staining. The expressions of bone metabolism-related genes alp, osteoprotectin (opn), osteoblast specific transcription factor (sp7), cathepsin K (ctsk), tracp, and Runt family transcription factor 2b (runx2b) in each group were determined using quantitative polymerase chain reaction. The results showed that all components of Lycii Fructus improved the formation area of the first vertebrae, the staining light density value, and the number of vertebrae joints in juvenile zebrafish and the Lycium barbarum polysaccharide (LBP) treatment group exerted the best effect. In addition, LBP prevented the formation of bone resorption lacunae in zebrafish scales, increased ALP activity, decreased TRAP activity, up-regulated the alp, sp7, and opn genes, and lowered the expressions of ctsk and tracp genes. In conclusion, LBP regulated the activity of osteoblasts and osteoclasts, reduced bone resorption, promoted bone formation and enhanced bone density, which might be the main anti-osteoporosis active fraction of Lycii Fructus. This study provided modern scientific evidence for the scientific connotation of the traditional effect of "strengthening bones and muscles" of Lycii Fructus, provided the reference for the evaluation of the anti-osteoporosis activity of traditional Chinese medicine based on zebrafish adult model, and provided beneficial enlightenment for the bone health needs of the aging society population.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect and mechanism of Zuoguiyin (ZGY, a Chinese medical remedy for regulating qi and nourishing yin) on expression of ovarian follicle-stimulating hormone receptor (FSHR) in rats during peri-menopausal period (PMP).</p><p><b>METHODS</b>PMP rats were administered with low (13.78 g/kg), middle (20.67 g/kg) and high (31.00 g/kg) dose ZGY respectively by gastrogavage for eight weeks. FSHR mRNA and protein expressions were detected by RT-PCR and immunohistochemistry respectively. Besides, granulosa cells, collected from pregnant mare serum treated nonage rats, were incubated, and the level of FSHR mRNA expression in the cultured cells were detected after various disposals.</p><p><b>RESULTS</b>(1) Ovarian levels of FSHR mRNA and protein expressions in PMP rats were significantly lower than those in young rats (P<0.01), but were up-regulated significantly by ZGY treatment (P<0.01). (2) As compared with the control, FSHR mRNA expression increased in cultured granulosa cells after treated by ZGY extract; the increasing effect of ZGY was enhanced by combined treatment with Forskolin and attenuated by Genistein (a tyrosine protein kinase inhibitor).</p><p><b>CONCLUSION</b>ZGY could improve the ovarian functions during PMP by up-regulating the expression of FSHR and raise the ovarian responsibility to FSH, which may be possibly realized by activating cAMP-protein kinase and tyrosine protein kinase signal pathway.</p>