Up-regulation of VEGF by MC3T3-E1 cells treated with curculigoside.

Empirical evidence has shown that curculigoside, the main active compound of the traditionally used Chinese herb, Curculigo orchioides (Amaryllidaceae, rhizome), affects bone formation and fracture healing. However, the mechanistic details of these processes remain unclear. Therefore, the effects of curculigoside on immortalized, pre-osteoblastic mouse MC3T3-E1 cells was investigated. Following treatment with curculigoside, MC3T3-E1 cells exhibited an increased rate of proliferation. Higher levels of vascular endothelial growth factor (VEGF), Fms-like tyrosine kinase-1 (Flt-1) and bone morphogenetic protein-2 (BMP-2) were also detected in cell supernatants and cell lysates by ELISA and western blot analysis, respectively. Furthermore, the stimulatory effect of curculigoside was observed at relatively low doses (i.e. 10-100 µg/mL). In combination, these responses to treatment with curculigoside elucidate mechanistic details underlying the therapeutic effects of Curculigo orchioides on bone, and identifies these molecules as potential targets for the treatment of common metabolic bone diseases.

[Study of Fufang Haishe capsule against cell apoptosis].

OBJECTIVE: To study mechanismt of Fufang Haishe capsule for dementia by observing the effect of it on PC-12 cell apoptosis, which was induced by beta-amyloid protein (Abl-42). METHOD: Nerve growth factor (NGF) was used to cultivate the PC-12 cells. Fufang Haishe capsule at different concentrations was added into the culture medium so as to identify the nontoxic concentrations with MTT. To analyze the PC-12 cell apoptosis respectively by MTT assay, Flow cytometry (FCM technique) with different concentrations of Fufang Haishe capsule (0.01, 0.1, 1, 5 mg x mL(-1)), adding Ab or not Western blot was used to detect apoptosis which was measured on the implementation of caspase-9 and caspase-3 activity. RESULT: Fufang Haishe capsule could significantly inhibit the apoptosis of PC-12 cells induced by Abeta with increased colorimetric MTT asay ( compare among the control group and concentration 0, 0.01, 0.1, 1 and 5 mg x mL(-1) group, which is the same below: 1.75 +/- 0.12, 0.73 +/- 0.35, 0.79 +/- 0.11, 0.83 +/- 0.07, 1.31 +/- 0.07, 1.80 +/- 0.38, P < 0.01) and the decreased apoptosis rate of the cells which was analysed by flow cytometry (1.93 +/- 0.41)%, (46.17 +/- 4.08)%, (35.35 +/- 4.63)%, (28.62 +/- 3.81)%, (15.13 +/- 3.15)%, (7.84 +/- 1.76)%, P < 0.01. In addition, Fufang Haishe capsule inhibited the activity of caspase-9 and caspase-3 of PC-12 cells which was induced by Abeta. CONCLUSION: Fufang Haishe capsule significantly inhibite apoptosis of PC-12 cells induced by Abeta. The mechanism might be that Fufang Haishe capsule decrease the activity of the apoptosis implementing protein,caspase-9 and caspase-3.

[Inhibitory effect of sinomenine on expression of cyclooxygenase-2 in lipopolysaccharide-induced PC-12 cells].

OBJECTIVE: To study the effects of sinomenine (Sin) on cell proliferation, intracellular expression of cyclooxygenase-2 (COX-2), and production of PGE2 in lipopolysaccharide-induced PC-12 cells, To explore the Sin's mechanism on nerve cell. METHOD: PC-12 cells were cultured with nerve growing factors (NGF), and pretreated with Sin at various concentrations (0, 3 x 10(-6), 30 x 10(-6), 150 x 10(-6) mol x L(-1)) for 2 hours, then with or without stimulation of lipopolysaccharide (LPS). The proliferation activity of PC-12 cells was determined by 3H-TdR incorporation, and the production of PGE2 in culture supernatants of PC-12 cells was detected with competitive ELISA. Expression of COX-2 mRNA in PC-12 cells was analyzed by semi-quantitative RT-PCR, and expression of COX-2 protein was estimated by Western blot method and cellular enzyme immunoassay. Nuclear factor-kappa B (NF-kappaB) activity in whole-cell extract of PC-12 cells was also measured by an ELISA-based method. RESULT: The data showed that Sin down-regulated the expression of COX-2 mRNA and protein, and reduced the production of PGE2 in the LPS-stimulated PC-12 cells which correlated with Sin's concentrations positively. In addition, NF-kappaB activity in LPS-stimulated cells was suppressed significantly by Sin. No inhibition of proliferation of PC-12 cells due to Sin treatment was observed. CONCLUSION: Sin mediates the down-regulation of expression of COX-2 and production of induced PGE2 in PC-12 cells by suppressing the activity of NF-kappaB.