MiR-7, miR-9 and miR-375 contribute to effect of Exendin-4 on pancreatic ß-cells in high-fat-diet-fed mice.

PURPOSE: The purpose of this study was to test whether glucagon-like peptide-1 (GLP-1) receptor activation preserved pancreatic ß-cells via the regulation of microRNAs and target genes in high-fat-diet-fed mice. METHODS: C57BL/6 male mice were simultaneously treated with high-fat-diet (HFD) and GLP-1 analogue, Exendin-4 (Ex-4) (3 µg/kg/day or 30 µg/kg/day), i.p. or vehicle, for consecutive 13 weeks. Fasting blood glucose, postprandial blood glucose, ΔI30/ΔG30, HOMA-IR and HOMA-% ß were measured in each group. Pancreatic ß-cell mass was assessed by immunohistochemistry. The expression of miRNAs and related downstream genes were investigated using quantitative real-time PCR. RESULTS: Thirteen weeks of Ex-4 treatment significantly reduced body weight and food intake in HFD-fed mice (P.

Design and synthesis of novel hydroxypyridinone derivatives as potential tyrosinase inhibitors.

Two groups of novel hydroxypyridinone derivatives 6(a-e) and 12(a-c), were designed as potential tyrosinase inhibitors, and synthesized using kojic acid as a starting material. The tyrosinase inhibitory activity of these two groups was demonstrated to be potent, especially compounds 6e and 12a, whose IC50 values for monophenolase activity were 1.95µM and 2.79µM, respectively. Both of these values are lower than that of kojic acid (IC50=12.50µM). Compounds 6e and 12a were investigated for the inhibitory effect on diphenolase activity. The results showed that the inhibitory mechanism of these two compounds was reversible and that the inhibitory type was a competitive-uncompetitive mixed-type. The values of IC50 of 6e and 12a on the diphenolase activity of tyrosinase were determined to be 8.97µM and 26.20µM, respectively. The inhibitory constants (KI and KIS) of 6e were determined as 17.17µM and 22.09µM, respectively; and the KI and KIS values of 12a were 34.41µM and 79.02µM, respectively. Compound 6e showed a greater ability to reduce copper and a stronger copper chelating ability than kojic acid.

[Synthesis and characterization of non fluorescent ZnS nano clusters].

Zinc sulfide nano clusters were synthesized and characterized. A kind of method using zinc sulfide nanoparticles cluster cation exchange reaction(CX) to detect trace biological molecules was established. Non fluorescent ZnS nanoparticles (NCCs) were synthesized and characterized. The property of nano clusters directly influences the detection results. Through transmission electron microscopy images and X-ray diffraction, nano clusters which could quickly release a mass of Zn2+ from rapid cation exchange reaction were known to be porous and generate fluorescence signal under the action of zinc reagent. The external crystal arranges loosely compared to the internal, which is conducive to rapid cation exchange, and the crystal size is related to heating time. It was demonstrated that the smallest nanocluster had a relative large surface area and higher cationic exchange efficiency through the determination of the specific surface area of nano clusters for detecting surface area and pore size. Three methods (acid dissolution method, cation exchange and micro wave aided by cation exchange) which effected Zn2+ release performance were experimented. It turned out that microwave auxiliary cation exchange method had high SNR, simple operation, and could be used in zinc sulfide nanoparticle immunoassay. Having compared the relations between the release efficiency, target binding force of ZnZ2+ and its average diameter, the results show that the nano cluster size of 44 nm exhibits the highest cation exchange efficiency. All these features make the ZnS nanocluster cation exchange amplifier to be a highly sensitive, fairly biocompatible, low-cost and environment friendly detection tool in the detection of biomolecules.

Terbium promotes adhesion and osteogenic differentiation of mesenchymal stem cells via activation of the Smad-dependent TGF-ß/BMP signaling pathway.

With its special physical and chemical properties, terbium has been widely used, which has inevitably increased the chance of human exposure to terbium-based compounds. It was reported that terbium mainly deposited in bone after introduction into the human body. Although some studies revealed the effects of terbium on bone cell lines, there have been few reports about the potential effect of terbium on adhesion and differentiation of mesenchymal stem cells (MSCs). In this study, we investigated the effects of terbium on the adhesion and osteogenic and adipogenic differentiation of MSCs and the associated molecular mechanisms. Our data reveal that terbium promoted the osteogenic differentiation in a time-dependent manner and conversely inhibited the adipogenic differentiation of MSCs. Meanwhile, the cell-cell or cell-matrix interaction was enhanced by activating adherent-related key factors, which were evaluated by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Real-time RT-PCR and Western blot analysis were also performed to further detect osteogenic and adipogenic biomarkers of MSCs. The regulation of terbium on differentiation of MSCs led to the interaction between the transforming growth factor ß/bone morphogenetic protein and peroxisome-proliferator-activated receptor γ (PPARγ) signaling pathways, resulting in upregulation of the osteogenic master transcription factors, such as Runt-related transcription factor 2, bone morphogenetic protein 2, collagen I, alkaline phosphatase, and osteocalcin, and downregulation of the adipogenic master transcription factors, such as PPARγ2. The results provide novel evidence to elucidate the mechanisms of bone metabolism by terbium and may be helpful for more rational application of terbium-based compounds in the future.

Lactones from Ficus auriculata and their effects on the proliferation function of primary mouse osteoblasts in vitro.

Bioassay-guided fractionation of the petroleum ether, chloroform and EtOAc extracts of the stems of Ficus auriculata led to the isolation of five new 12-membered lactones (3R,4R)-4-hydroxy-de-O-methyllasiodiplodin (1), 6-oxolasiodiplodin (2) and ficusines A-C (3-5), together with three known related analogues (6-8). The structures of the new compounds were elucidated by comprehensive spectroscopic data. The absolute configurations of 3 and 8 were established by single crystal X-ray diffraction analysis. Compounds 3-5 represent the first 12-membered lactones with a quinone ring unit. Compounds 6 and 7 exhibited significant proliferation function of primary osteoblasts (OBs) in vitro. Especially, the promotion rate of 6 reached 151.55±1.34% (P<0.001) at the concentration of 100 µM.

TGF-ß/BMP signaling pathway is involved in cerium-promoted osteogenic differentiation of mesenchymal stem cells.

The extensive applications of cerium (Ce) increased the chance of human exposure to Ce and its compounds. It was reported that Ce was mainly deposited in the bone after administration. However, the potential effect and mechanism of Ce on bone metabolism are not well understood. In this study, we investigated the cellular effects of Ce on the differentiation of mesenchymal stem cells (MSCs) and the associated molecular mechanisms. The results indicated that Ce promoted the osteogenic differentiation and inhibited the adipogenic differentiation of MSCs at cell level. Genes involved in transforming growth factor-ß/bone morphogenetic proteins (TGF-ß/BMP) signaling pathway were significantly changed when the MSCs were exposed to 0.0001 µM Ce by RT(2) Profiler™ PCR Array analysis. The expression of genes and proteins related to pathways, osteogenic, and adipogenic biomarkers of MSCs upon interaction with Ce was further confirmed by quantitative real-time reverse transcriptase polymerase chain reaction (Q-PCR) and Western blot analysis. The results suggest that Ce exerts the effects by interacting with bone morphogenetic protein receptor (BMPR) and activates TGF-ß/BMP signaling pathway, leads to the up-regulation of the osteogenic master transcription factor, runt-related transcription factor 2 (Runx 2), and the down-regulation of the adipocytic master transcription factor, peroxisome proliferator-activated receptor gamma 2 (PPARγ2). Runx2, which subsequently up-regulates osteoblast (OB) marker genes collagen I (Col I) and BMP2 at early stages, alkaline phosphatase (ALP), and osteocalcin (OCN) at later stages of differentiation, thus driving MSCs to differentiate into OBs. The results provide novel evidence to elucidate the mechanisms of bone metabolism by Ce.

A triazatruxene-based glycocluster as a fluorescent sensor for concanavalin A.

A new triazatruxene-based fluorescent glycocluster has been designed, synthesized, and fully characterized by NMR spectroscopy and mass spectrometry. Furthermore, its specific and selective binding properties with concanavalin A (Con A) have been investigated by fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and turbidity assay. The obtained results showed that the multivalent mannose-modified triazatruxene exhibited specific binding with Con A, but no binding to peanut agglutinin (PNA) lectin or bovine serum albumin (BSA), corresponding to a two-orders-of-magnitude higher affinity than that of monovalent mannose ligands. Most interestingly, a fluorescence enhancement of the triazatruxene-based glycocluster was observed upon binding with Con A because of hydrophobic interactions involving sites close to the triazatruxene moiety. Furthermore, the inhibitory ability of the triazatruxene-based glycocluster against ORN178-induced haemagglutination has been investigated by haemagglutination inhibition assay. The results indicated selective binding with ORN178.

Synthesis of perylene bisimide-centered glycodendrimer and its interactions with concanavalin A.

A novel glycodendrimer based on 18 peripheral α-D-mannoses functionalized perylene bisimide derivative PBI-18-Man was synthesized and its selectively binding interactions for Con A were investigated by CD spectra and turbidity assay, which exhibited strong binding affinity for Con A with the binding constant of 1.3×10(8) M(-1) (7.2×10(6) M(-1) for monomeric mannose, valency corrected), 3 orders of magnitude higher affinity than the monovalent mannose ligand. Furthermore, the inhibitory activity for Con A was studied by ELLA experiment, showed 2 times inhibitor activity than the reference compound (α-MMP).

Multivalent glycoclusters constructed by chiral self-assembly of mannose functionalized perylene bisimide.

Water-soluble perylene bisimide derivative 7 modified with six mannoses was synthesized and its self-assembled properties were studied by UV-Vis and CD spectroscopy, which revealed an interesting self-assembly with a solvent-tuning chiral conformation in H(2)O-DMSO solution. As H(2)O was added to the DMSO solution until a 60% (or 70%) v/v proportion was achieved, the self-assembly of the mannose functionalized compound 7 exhibited a left-handed helical conformation. More interestingly, when the volume of H(2)O constituted beyond 85% of the solution, the conformation of the self-assembly turned out to be a right-handed helical conformation. Furthermore, the binding interactions between the self-assembly of compound 7 and Con A were investigated by turbidity assay, CD spectra, TEM and SEM images, and ELLA experiment, which indicated that the self-assembly of compound 7 as multivalent glycoclusters exhibited specific binding to Con A with an IC(50) value of 24 µM (144 µM, valency corrected), 10 times stronger than the reference compound (α-MMP).

Protein Tyrosine Kinase 7 Regulates EGFR/Akt Signaling Pathway and Correlates With Malignant Progression in Triple-Negative Breast Cancer.

PURPOSE: Triple-negative breast cancer (TNBC), the most aggressive subtype of breast cancer, is associated with high invasiveness, high metastatic occurrence and poor prognosis. Protein tyrosine kinase 7 (PTK7) plays an important role in multiple cancers. However, the role of PTK7 in TNBC has not been well addressed. This study was performed to evaluate the role of PTK7 in the progression of TNBC. METHODS: Correlation of PTK7 expression with clinicopathological parameters was assessed using tissue microarray immunohistochemistry (IHC) staining in 280 patients with breast cancer. PTK7 expression in TNBC (MDA-MB-468, MDA-MB-436 and MDA-MB-231) and non-TNBC (MCF7 and SK-BR-3) breast cancer cell lines were examined using immunoblotting assay. PTK7 correlated genes in invasive breast carcinoma were analyzed using cBioPortal breast cancer datasets including 1,904 patients. PTK7 overexpressed or knockdown TNBC cell lines (MDA-MB-468 and MDA-MB-436) were used to analyze the potential roles of PTK7 in TNBC metastasis and tumor progression. A TNBC tumor bearing mouse model was established to further analyze the role of PTK7 in TNBC tumorigenicity in vivo. RESULTS: PTK7 is highly expressed in breast cancer and correlates with worse prognosis and associates with tumor metastasis and progression in TNBC. Co-expression analysis and gain- or loss-of-function of PTK7 in TNBC cell lines revealed that PTK7 participates in EGFR/Akt signaling regulation and associated with extracellular matrix organization and migration genes in breast cancer, including COL1A1, FN1, WNT5B, MMP11, MMP14 and SDC1. Gain- or loss-of-function experiments of PTK7 suggested that PTK7 promotes proliferation and migration in TNBC cell lines. PTK7 knockdown MDA-MB-468 cell bearing mouse model further demonstrated that PTK7-deficiency inhibits TNBC tumor progression in vivo. CONCLUSION: This study identified PTK7 as a potential marker of worse prognosis in TNBC and revealed PTK7 promotes TNBC metastasis and progression via EGFR/Akt signaling pathway.

[Correlation of real-time continuous monitoring system with venous glucose and capillary glucose values].

OBJECTIVE: To study the correlation of real-time continuous monitoring system (RT-CGMS) with venous glucose and capillary glucose values. METHODS: A total of 33 diabetics received RT-CGMS for 5 days. Fasting venous glucose values were measured at Days 1, 3 and 5 and capillary glucose values recorded 7 times daily. The methods of correlation coefficient, error grid analysis (EGA) and Bland-Altman analysis were employed to assessed the correlation, accuracy and agreement of RT-CGMS with venous glucose and capillary glucose values respectively. The mean amplitude of glucose excursions (MAGE) was calculated during RT-CGMS testing periods. RESULTS: (1) The correlation coefficient of RT-CGMS with vein glucose and capillary glucose values were 0.936, 0.933 (P < 0.01); (2) The analysis results of EGA showed that 98.67%, 98.64% of venous and capillary values fell in the A and B zones and 1.33%, 1.36% fell in the D zone; (3) The agreement analysis showed that RT-CGMS readings were in close agreement with venous glucose and capillary glucose results; (4) The patients at the same MAGE levels had obvious differences in HbA1C. CONCLUSION: There is a high level of correlation, accuracy and agreement between RT-CGMS and venous glucose and capillary glucose values.

[Characteristics of glycometabolism in the first-degree relatives of type 2 diabetes patients assessed by continuous glucose monitoring system].

OBJECTIVE: To investigate the characteristics of glycemic stability in the first-degree relatives of type 2 diabetes mellitus (T2DM) patients by continuous glucose monitoring system (CGMS). METHODS: Twenty-two first-degree relatives (FDRs) of T2DM patients and 28 age and gender-matched controls underwent CGMS to obtain the mean blood glucose (MBG), standard deviation of MBG (SDBG), mean of daily differences (MODD), and mean amplitude of glycemic excursions (MAGE). Oral glucose tolerance test (OGTT) was conducted. Blood glucose, serum lipids, and serum insulin were assayed. The insulin sensitivity and resistance was assessed by HOMA-beta, HOMA-IR, DeltaI(30)/DeltaG(30) and modified beta cell function index (MBCI). RESULTS: There were no significant differences between the FDR and control groups in the levels of plasma glucose in OGTT, MBG, SDBG, and MOOD. However, the MAGE level of the FDR group was (2.3 +/- 0.5) mmol/L, significantly higher than that of the control group [(2.0 +/- 0.6) mmol/L, P < 0.05]. The MBCI level of the FDR group was 17.6 (16.9 - 50.0), significantly lower than that of the control group [36.0 (15.7 - 59.6), P < 0.05]. There were no significant differences in the serum lipids profile, body fat distribution, HOMA-beta, HOMA-IR, and DeltaI(30)/DeltaG(30) between these two groups. CONCLUSION: The excursion of blood glucose is greater in the FDRs of T2DM patients. CGMS is more sensitive to discover such change than OGTT.

[Piezoelectric property of novel biological piezoelectric ceramic HALNK and its effect on the functional expression of rat osteoblast cells].

OBJECTIVE: To test the Piezoelectric property of novel biological piezoelectric ceramic HALNK and its effect on the proliferation and differentiation of rat osteoblast cells. METHODS: The biological piezoelectric ceramic HALNK1/9 and HALNK5/5 were prepared by mixing Hydroxyapatite (HA) with lithium sodium potassium niobate (LNK) piezoelectric ceramic at a ratio of 1/9 and 5/5 (wt/wt), respectively. After poling treatment, the piezoelectric constants were measured. The osteoblast cells were then seeded on the surfaces of HALNK. The proliferation and differentiation activities of the osteoblast cells were evaluated by MTT assays, ALP activities and scanning electron microscopy examinations. RESULTS: Cells grown on the surfaces of HALNK showed normal morphology, and had better proliferation and differentiation activities than the control. The growth of osteoblastic cells on the surface of HALNK1/9 was significantly better than others. CONCLUSION: The surface of HALNK 1/9 possesses better piezoelectric property and osteogenesis potential than HALNK5/5.

The solvent-free synthesis of 1,4-dihydropyridines under ultrasound irradiation without catalyst.

The condensation of aldehydes, ethyl acetoacetate and ammonium acetate result 1,4-dihydropyridines in 82-99% yields under ultrasound irradiation without solvent and catalyst at room temperature. Compared with conventional methods, the main advantages of the present procedure are milder conditions, shorter reaction time and higher yields.

Antioxidant and antimicrobial evaluation of carboxymethylated and hydroxamated degraded polysaccharides from Sargassum fusiforme.

In order to improve the bioactivity of the polysaccharide from Sargassum fusiforme (PSF), the degraded polysaccharide (DPSF) was modified by carboxymethylation, yielding carboxymethylated degraded polysaccharides (CDPSF), which were further modified to generate hydroxamated derivatives (HCDPSF). Both CDPSF and HCDPSF were characterized by Fourier transform infrared spectroscopy. The molecular weight of CDPSF and HCDPSF was found to be 354 kDa and 375 kDa, respectively. The in vitro antioxidant activity of CDPSF and HCDPSF was evaluated by determining the radical scavenging ability and total antioxidant activity. The results indicated that the antioxidant activity of CDPSF and HCDPSF was significantly improved when compared to those of DPSF. Antimicrobial assays indicated that both CDPSF and HCDPSF possessed a marked antimicrobial ability, while DPSF did not exhibit such effects under the same conditions. Such polysaccharide derivatives have potentials in the pharmaceutical and food industries.

Effect of zinc ion on the osteogenic and adipogenic differentiation of mouse primary bone marrow stromal cells and the adipocytic trans-differentiation of mouse primary osteoblasts.

A series of experimental methods including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test, alkaline phosphatase (ALP) activity measurement and Oil Red O stain and measurement were employed to assess the effect of zinc ion on the osteogenic and adipogenic differentiation of mouse primary bone marrow stromal cells (MSCs) and the adipogenic trans-differentiation of mouse primary osteoblasts. The results showed that except for individual concentrations of zinc ion there was no effect on the proliferation of MSCs and osteoblasts. Zinc ion inhibited the osteogenic differentiation of MSCs at all the concentrations tested. It also inhibited adipogenic differentiation at all concentrations tested except 10(-9)mol/L. Both of the inhibition effects were attenuated with time increasing. Zinc ion depressed adipocytic trans-differentiation of osteoblasts at concentrations of 10(-11) and 10(-10)mol/L, but the effect could be reversed to promote or even be removed when concentration was increased. It suggests that the influence of zinc ion on osteogenic, adipogenic differentiation of MSCs and adipocytic trans-differentiation of osteoblasts depends on zinc ion concentrations and incubation time. The protective effects of zinc ion on bone may be mediated by modulating differentiation of MSCs away from the adipocytes and inhibiting adipocytic trans-differentiation of osteoblasts. This may in turn promote osteoblast formation and reduce secretion of cytokines which may inhibit osteoclast formation and activation. These findings may be valuable for better understanding the mechanism of the effect of zinc ion on bone.

[Correlation between ITS genotype and geographical distribution of Pogostemon cablin].

To investigate the correlation between genotype and distribution of Pogostemon cablin by sequencing ITS1 and ITS2 genes, and provide molecular information for its germplasm evaluation, ITS1 and ITS2 genes of Pogostemon cablin from different localities were identified by PCR direct sequencing. The sequences of ITS1 and ITS2 genes were 424 bp and 380 bp in length, respectively. And nineteen base substitutions were observed in ITS1 gene, and five in ITS2 gene. The results showed a good correlation between genotype and distribution of Pogostemon cablin, and ITS gene sequencing could provide useful molecular information for germplasm evaluation of the plant species verification.

[Expression of long isoform leptin receptor and shortest membrane bound variant in peripheral blood mononuclear cells from the obese and normal individuals].

OBJECTIVE: To investigate the expression of the long isoform leptin receptor (OB-R(L)) and the shortest membrane bound variant (OB-R(S)) in peripheral blood mononuclear cells from the obese and normal individuals (6.08 ng/ml or 31.21 ng/ml). METHODS: Mononuclear cells were obtained from 30 obese individuals (BMI > 25 kg/m2) and 20 normal individuals (BMI < 23 kg/m2). RT-PCR was used to detect the expression of OB-R(S) and OB-R(L). The level of serum leptin was measured with immunoradiometric assay. RESULTS: OB-R(S) was expressed in all individuals, and OB-R(L) was expressed in 38 individuals. OB-R(L) was not expressed in the 12 obese individuals with the BMI > 39 kg/m2. The expression level of OB-R(S) was 4 times higher than that of OB-R(L). There was no significant difference in the expression of either isoforms between men and women. The relative expression of both OB-R(S) and OB-R(L) isoforms was significantly lower and the serum leptin level was significantly higher in the obese individuals (6.08 ng/ml or 31.21 ng/ml). The leptin receptor expression levels were significantly negatively correlated with BMI and serum leptin level. CONCLUSION: Both OB-R(S) and OB-R(L) are expressed in the peripheral blood mononuclear cells from normal and the medium obese subjects with a consistent predominance of OB-R(S). There is no significant difference in the expression of OB-R(S) and OB-R(L) between men and women. Compared with normal individuals, the expression of OB-R(S) and OB-R(L) in human mononuclear cells is lower.

[Comparison of antioxidative and antitumor activities of six flavonoids from Epimedium koreanum].

OBJECTIVE: To study the antioxidative and antitumor activities of flavonoids isolated from Epimedium koreanum. METHOD: The compounds were separated by column chromatography with silica gel and Sephadex LH-20, and identified by spectral a- nalysis (ESI-MS, 1H-NMR and 13C-NMR) respectively. DPPH radical scavenging assay and MTT assay were used to observe the antioxidative and antitumor abilities. RESULT: Six compounds were isolated from the the ethyl acetate extract of the aerial part. Their structures were identified as icariin (I), luteolin (II), baohuoside II (III), hyperoside (IV), epimedokoreanin B (V) and baohuoside I (VI). The results indicated that at concentrations of 3. 125-200 micromol x L(-1), compound I, III and VI had no ability to scavenge the DPPH radical, but the scavenging ability of compounds II, IV and V were stronger than that of Vit C in dose-dependant manner. Compounds I, II, V and VI could inhibit the proliferation of MCF-7 and HepG2 in dose-dependant manner, but compounds III and IV had no effect on the proliferation. CONCLUSION: The antitumor activity of E. koreanum may be partially related to the antioxidantive activity of flavonoids.

[Study on chemical constituents from rhizomes of Actaea asiatica].

OBJECTIVE: To investigate the chemical constituents of the rhizomes of Actaea asiatica in order to obtain a more comprehensive understanding of its effective components. METHOD: Compounds were separated by silica gel chromatography, RP-C18 chromatography and semi-preparative high performance liquid chromatography, and their structures were established by spectral analysis and chemical evidence. RESULT: Six compounds were isolated from the ethyl acetate extract. Their structures were identified as 25-O-acetylcimigenol (1), 12beta-hydroxycimigenol (2), 23-epi-26-deoxyactein (3), 27-deoxyacetylacteol (4), 26-deoxycimicifugenin (5) and beta-sitosterol (6). CONCLUSION: All these compounds mentioned above were isolated from the plant for the first time.