The OPG/RANKL/RANK system plays an important role in osteoclastogenesis and represents a great progress in bone biology. RANKL, which expresses on the surface of osteoblast/stromal cells and activated T cells, binds to RANK on the osteoclastic precursors or mature osteoclasts, and promotes osteoclastogenesis and bone resorption. While osteoprotegerin (OPG), which is expressed by osteoblasts/stromal cells, strongly inhibits bone resorption by binding to its ligand RANKL and thereby blocks the interaction between BANKL and RANK. A number of cytokines and hormones exert their effects on bone metabolism by regulating the OPG/RANKL ratio in the bone marrow microenvironment. RANK is also expressed on mammary epithelial cells and RANKL expression in these cells is induced by pregnancy hormones, RANKL and RANK are essential for the formation of the lactating mammary gland and the transmission of maternal calcium to neonates in mammalian species. Modulation of these systems provides a unique opportunity to develop novel therapeutics to inhibit bone loss in osteoporosis, rheumatoid arthritis, and bone metastasis of cancer. Further research should be focused on the cooperation of OPG/RANKL/RANK system with other signal pathways and the interactions among bone remodeling, immune system and endocrinology system. Currently, the development of OPG analogues or compounds which may stimulate OPG expression is becoming an attractive industry which may be profitable to both patients and manufacturers.
Animals ; Bone Resorption ; immunology ; metabolism ; Humans ; Osteoclasts ; cytology ; metabolism ; pathology ; Osteogenesis ; drug effects ; genetics ; immunology ; Osteoprotegerin ; metabolism ; physiology ; RANK Ligand ; metabolism ; physiology ; Receptor Activator of Nuclear Factor-kappa B ; metabolism ; pharmacology ; physiology ; T-Lymphocytes ; drug effects ; immunology

Functional analysis of new genes is playing a central role in postgenomic era. Here we reviewed several main strategies including bioinformatics, gene transduction, antisense technology, certain gene silence induced by RNA interference (RNAi), transgene and gene knockout and artificial chromosome transduction.
Animals ; Computational Biology ; methods ; Genes ; physiology ; Humans ; Transduction, Genetic ; methods

Using the isolated total RNA from osteosacoma cell line MG63, the cDNA encoding human OPG was amplified by RT-PCR. A recombinant adenoviral vector carrying cDNA of OPG was constructed and OPG expression in mouse myoblast C2C12 cells was confirmed by Western blot and ELISA. The secreted expression of OPG protein persisted more than 6 weeks in vitro, and the growth of C2C12 cells infected by recombinant adenoviral were in good state. Osteoclasts derived from mouse bone marrow cells infected with recombinant adenoviral made less number of TRAP positive cells and resorption pits formed on dentine slices.
Adenoviridae ; genetics ; Animals ; Blotting, Western ; Cell Line ; Enzyme-Linked Immunosorbent Assay ; Genetic Vectors ; genetics ; Humans ; Male ; Mice ; Mice, Inbred BALB C ; Osteoclasts ; metabolism ; Osteoprotegerin ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

OBJECTIVETo express human osteoprotegerin (OPG) in E. Coli and analyze its bioactivity in vitro.

METHODSSynthetic oligonucleotides were used to amplify human OPG gene by RT-PCR from total RNA of human osteosarcoma cell line MG63. The OPG cDNA coding for 380 amino acid residues was inserted into prokaryotic expression vector pRSET-A, transformed into competent E. Coli BL21, and induced by 0.1 mmol/l IPTG. SDS-PAGE and Western blot were performed to identify OPG-6His fusion protein. After purified by affinity chromatography, 1,000 microg/L or 1,500 microg/L of OPG-6His were added into the mouse bone marrow cells culture medium. The number of tartrate-resistant acid phophatase (TRAP)-positive multinucleated cells and resorption pits were counted to assess the bioactivity of expression products.

RESULTSThe sequence of OPG mature peptide encoding cDNA obtained in this experiment was as same as reported. SDS-PAGE showed 24% of total bacterial protein was of OPG-6His fusion protein. Western blot assay demonstrated that the molecular weight of recombinant protein was about 46 KD and could react specifically with human anti-OPG antibody. The mouse bone marrow cells were induced by 1alpha, 25-dihydroxyvitaminD3 (10(-8) mol/L) and Dexamethasone (10(-7) mol/L) to form osteoclastic-like multinucleated cells. 1,500 microg/L of purified OPG-6His protein could decrease the number of resorption pits and TRAP-positive multinucleated cells in vitro (P < 0.05), but it didn't show the same effects when the concentration of OPG-6His fusion protein was of 1,000 microg/L.

CONCLUSIONSHuman OPG-6His fusion protein is expressed and purified in E. Coli. The expression products have moderate inhibitory effects on osteoclast differentiation and bone resorption in vitro only when excessive amount of proteins are added into the culture medium, indicating that prokaryotic expression of fuctionalal OPG protein awaits further investigation.

Cell Differentiation ; drug effects ; Cell Line, Tumor ; Cloning, Molecular ; Escherichia coli ; genetics ; Glycoproteins ; biosynthesis ; genetics ; Humans ; Osteoclasts ; drug effects ; physiology ; Osteoprotegerin ; Receptors, Cytoplasmic and Nuclear ; biosynthesis ; genetics ; Receptors, Tumor Necrosis Factor ; Recombinant Fusion Proteins ; biosynthesis ; pharmacology

OBJECTIVETo compare the tissue formation and the content of polysaccharide between the wild Dendrobium candidum and the cultured ones and to find any existed differences.

METHODBare-handed microtomy and photomicrography; The content of polysaccharide is determined by phenol-sulphuric acid method.

RESULT AND CONCLUSIONThere are no marked noticeable differences between the wild D. candidum and the cultured ones in terms of the tissure formation and the content of polysaccharide.

Dendrobium ; anatomy & histology ; chemistry ; growth & development ; Plant Stems ; anatomy & histology ; chemistry ; growth & development ; Plants, Medicinal ; anatomy & histology ; chemistry ; growth & development ; Polysaccharides ; analysis ; Tissue Culture Techniques

Ginsenoside Rb1 is a representative component of panaxadiol saponins, which belongs to dammarane-type tritepenoid saponins and mainly exists in family araliaceae. It has been reported that ginsenoside Rb1 has diverse biological activities. In this paper, the research development in recent decade on its pharmacological effects of cardiovascular system, anti-senility, reversing multidrug resistance of tumor cells, adjuvant anti-cancer chemotherapy, promoting peripheral nerve regeneration, et al, are reviewed.
Aging ; drug effects ; Animals ; Cardiovascular System ; drug effects ; pathology ; Drug Resistance, Neoplasm ; drug effects ; Ginsenosides ; metabolism ; pharmacokinetics ; pharmacology ; Humans ; Nerve Regeneration ; drug effects

OBJECTIVETo observe the protective effects of total glycosides Rubus parviflolius (TGRP) on local cerebral ischemic.

METHODThe local cerebral ischemia in rat was made by middle cerebral artery occlusion(MACO). The infraction weight was determined by TTC stain. SOD, MDA, GSH and apoptotis were determined with different method respectively.

RESULTTGRP 20, 10 mg x kg(-1) ig markedly improved the abnormal nervous symptoms, incredsed the SOD, GSH activity and reduced contentes of MDA in brain of MACO rat, TGRP 20 mg x kg(-1) ig significantly decreased the numbers of apoptotic cells in ischemic cortex.

CONCLUSIONTGRP has protective effects against cerebral infraction, and its mechanism may be related to anti-apoptotis and free radical.

Animals ; Apoptosis ; drug effects ; Behavior, Animal ; drug effects ; Brain ; metabolism ; pathology ; Glycosides ; isolation & purification ; pharmacology ; Infarction, Middle Cerebral Artery ; metabolism ; pathology ; physiopathology ; Male ; Neuroprotective Agents ; pharmacology ; Plant Leaves ; chemistry ; Plant Stems ; chemistry ; Plants, Medicinal ; chemistry ; Rats ; Rats, Sprague-Dawley ; Rosaceae ; chemistry

OBJECTIVETo explore effects of exendin-4 on the metabolism of extracellular matrix (ECM) in human mesangial cells (HMC) cultured in the presence of high glucose and explore the possible mechanism.

METHODSHuman mesangial cells (HMC) were treated with exendin-4 under high glucose conditions. The cell proliferation was observed using CCK8 assay, and the expressions of collagen type I, fibronectin, transforming growth factor-β1 (TGFβ1) expression and extracellular signal- regulated kinase (ERK) signaling pathway activity were assessed using Western blotting.

RESULTSExendin-4 inhibited cell proliferation and the expressions of collagen type I, fibronectin and TGFβ1 and reversed ERK phosphorylation in high glucose-induced HMC.

CONCLUSIONExendin-4 can regulate ECM metabolism in HMC cultured in high glucose by inhibiting TGFβ1/ERK pathway, suggesting the beneficial effects of exendin-4 in preventing and treating diabetic nephropathy.

Cell Proliferation ; Cells, Cultured ; Collagen Type I ; metabolism ; Culture Media ; chemistry ; Diabetic Nephropathies ; Extracellular Matrix ; metabolism ; Fibronectins ; metabolism ; Glucose ; chemistry ; Humans ; MAP Kinase Signaling System ; Mesangial Cells ; drug effects ; Peptides ; pharmacology ; Phosphorylation ; Signal Transduction ; Transforming Growth Factor beta1 ; metabolism ; Venoms ; pharmacology

BACKGROUNDPrevalence of inadequate glycaemic control among patients with type 2 diabetes mellitus (T2DM) remains high. We assessed glycaemic control in the real-life practice among people with T2DM in metropolises in China who were treated with oral antidiabetic drugs (OAD) alone and to determine factors associated with inadequate glycaemic control in this population.

METHODSAn observational, cross-sectional multicentre study was conducted in 16 metropolitan medical centers. People with T2DM who had been followed-up before the index visit which occurred from January to September 2007 were included in the study. All subjects were ≥ 30 years of age at the time of T2DM diagnosis and had received monotherapy or combination therapy of OAD for at least 6 months. Demographic and clinical data were collected from medical records. The main study outcome was the inadequate glucose control rate, which was calculated by the proportion of patients with haemoglobin A(1C) (HbA(1C)) ≥ 6.5% detected on the index visit.

RESULTSIn this cohort of 455 patients with T2DM whose mean age was 60.6 years and mean disease duration was 6.1 years, 45.5% had inadequate glycaemic control. The mean (SD) HbA(1C) was 6.7% (1.3). Multivariate Logistic regression showed that physical inactivity, disease duration > 10 years, body mass index (BMI) ≥ 24 kg/m(2), low homeostasis model assessment of β-cell function (HOMA-β) index, less frequency of medical visit and hypertriglyceridaemia were independent determinants of inadequate glycaemic control. Higher incidence of self-reported hypoglycemia experience (47.1% vs. 34.8%, P = 0.008) and more fear of hypoglycemia quantified by Worry subscale of the Hypoglycaemia Fear Survey (HFS) II were happened in subjects with good glycemic control.

CONCLUSIONApproximately one half of these outpatients with T2DM from the metropolitan medical centers in China had inadequate glycaemic control treated with OAD alone, which raises the need for more effective educational and therapeutic approaches on management of hypertriglycemia, enhancing physical exercise and weight control, and at the same time, lowering the hypoglycemic risk and diminishing the hypoglycemic fear of patients.

Aged ; Asian Continental Ancestry Group ; Blood Glucose ; drug effects ; Cross-Sectional Studies ; Diabetes Mellitus, Type 2 ; blood ; drug therapy ; metabolism ; Female ; Glycated Hemoglobin A ; Humans ; Hypoglycemic Agents ; therapeutic use ; Logistic Models ; Male ; Middle Aged

BACKGROUNDMicroscope-integrated near-infrared indocyanine green video angiography (ICG-VA) has been used in neurosurgery for a decade. This study aimed to assess the value of intraoperative indocyanine green (ICG) video angiography with Flow 800 software in cerebrovascular surgery and to discover its hemodynamic features and changes of cerebrovascular diseases during surgery.

METHODSA total of 87 patients who received ICG-VA during various surgical procedures were enrolled in this study. Among them, 45 cases were cerebral aneurysms, 25 were cerebral arteriovenous malformations (AVMs), and 17 were moyamoya disease (MMD). A surgical microscope integrating an infrared fluorescence module was used to confirm the residual aneurysms and blocking of perforating arteries in aneurysms. Feeder arteries, draining veins, and normal cortical vessels were identified by the time delay color mode of Flow 800 software. Hemodynamic parameters were recorded. All data were analyzed by SPSS version 18.0 (SPSS Inc., USA). T-test was used to analyze the hemodynamic features of AVMs and MMDs, the influence on peripheral cortex after resection in AVMs, and superficial temporal artery to middle cerebral artery (STA-MCA) bypass in MMDs.

RESULTSThe visual delay map obtained by Flow 800 software had more advantages than the traditional playback mode in identifying the feeder arteries, draining veins, and their relations to normal cortex vessels. The maximum fluorescence intensity (MFI) and the slope of ICG fluorescence curve of feeder arteries and draining veins were higher than normal peripheral vessels (MFI: 584.24±85.86 vs. 382.94 ± 91.50, slope: 144.95 ± 38.08 vs. 69.20 ± 13.08, P < 0.05). The arteriovenous transit time in AVM was significantly shorter than in normal cortical vessels ((0.60 ± 0.27) vs. (2.08 ± 1.42) seconds, P < 0.05). After resection of AVM, the slope of artery in the cortex increased, which reflected the increased cerebral flow. In patients with MMD, after STA-MCA bypass, cortex perfusion of corresponding branches region increased and local cycle time became shorter.

CONCLUSIONIntraoperative ICG video angiography combined with hemodynamic parameter analysis obtained by Flow 800 software appears to be useful for intraoperative monitoring of regional cerebral blood flow in cerebrovascular disease.

Adolescent ; Adult ; Aged ; Cerebrovascular Circulation ; physiology ; Cerebrovascular Disorders ; surgery ; Female ; Fluorescein Angiography ; methods ; Humans ; Indocyanine Green ; Male ; Middle Aged ; Prospective Studies ; Software ; Young Adult