[Show abstract][Hide abstract] ABSTRACT: Background. Liraglutide (a glucagon-like peptide 1 analog) was used for the treatment of type 2 diabetes (T2DM) which could produce glucose-dependent insulin secretion. Aim. The aim was to investigate whether liraglutide could improve myofibril and mitochondria injury in skeletal muscle and the mechanisms in diabetic KKAy mice. Method. We divided the male KKAy mice into 2 groups: liraglutide group (250 μg/kg/day liraglutide subcutaneous injection) and model group; meanwhile, the male C57BL/6J mice were considered as the control. After 6 weeks, the ultrastructure of skeletal muscle was observed by electron microscope. The gene expressions of protein tyrosine phosphatase 1B (PTP1B), phosphatidylinositol 3-kinase (PI3K), and glucose transporter type 4 (GLUT4) were determined by real-time PCR. The protein levels of the above molecules and phospho-Akt2 (p-Akt2) were measured by Western blot. Results. Liraglutide significantly ameliorated the injury of mitochondria by increasing the number (+441%) and the area (+113%) of mitochondria and mitochondrial area/100 µm(2) (+396%) in skeletal muscle of KKAy mice. The results of real-time PCR and Western blot showed that liraglutide downregulated PTP1B while it upregulated PI3K and GLUT4 (P < 0.01). The protein level of p-Akt2/Akt2 was also increased (P < 0.01). Conclusion. These results revealed that liraglutide could improve myofibril and mitochondria injury in skeletal muscle against T2DM via PTP1B and PI3K/Akt2 signaling pathway.
Full-text · Article · Aug 2014 · International Journal of Endocrinology
[Show abstract][Hide abstract] ABSTRACT: A spirally hierarchical structure-based glucose enzymatic electrode was prepared in the experiment on the basis of that zinc oxide nanowires were hydrothermally synthesized on the surface of an Au cylindrical spiral formed by manually winding an Au fiber around an optical fiber core, and then glucose oxidase was immobilized on these nanowires by physical adsorption. The surface morphologies of the spirally hierarchical structures and corresponding enzymatic electrodes were extracted, and the electrochemical performances of the enzymatic electrodes were characterized. The results indicated that the synthesizing parameters of zinc oxide nanowires affected significantly the surface morphologies of the glucose oxidase immobilization on the spirally hierarchical structures, and the performances of related glucose sensors. As the Zn2+ concentration of growth solution was set at 25 mM, the surface morphology was determined as roughness to be 0.10 μm and correlation length 0.29 μm, resulting in a better immobilization of glucose oxidase upon zinc oxide nanowires. In this case, the sensitivity of the glucose sensor was determined to be 2.15 μA mM−1 cm−2, the linear range was 0–4.50 mM, the low detection limit was 9.20 μM and Michaelis-Menten constant was 3.68 mM. The results not only benefited the batch production of the spirally hierarchical structure-based enzymatic electrodes, but also significantly improved the performances of the glucose sensors.
No preview · Article · Aug 2014 · Chinese Journal of Analytical Chemistry
[Show abstract][Hide abstract] ABSTRACT: Background
Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease mediated by T cells. The aim of the present study was to investigate the therapeutic efficacy of synthetic peptides (HP-R1, HP-R2 and HP-R3), derived from the sequence of 65-kD mycobacterial heat shock protein (HSP), in the treatment of RA using adjuvant-induced arthritis (AA) animal model.
AA was induced by a single intradermal injection Freund’s complete adjuvant in male Lewis rats. At the first clinical sign of disease, rats were administered nasally by micropipette of peptides or phosphate buffer saline (PBS). Disease progression was monitored by measurement of body weight, arthritis score and paw swelling. The changes of histopathology were assessed by hematoxylin eosin staining. The serum levels of tumor necrosis factor (TNF) - alpha and interleukin (IL)-4 were measured by enzyme-linked immunosorbent assay (ELISA).
The peptides efficiently inhibited the footpad swelling and arthritic symptoms in AA rats. The synthetic peptides displayed significantly less inflammatory cellular infiltration and synovium hyperplasia than model controls. This effect was associated with a suppression of pro-inflammatory cytokine TNF-alpha production and an increase of anti-inflammatory cytokine IL-4 production after peptides treatment.
These results suggest that the synthetic peptides derived from HSP65 induce highly effective protection against AA, which is mediated in part by down-regulation of inflammatory cytokines, and support the view that the synthetic peptides is a potential therapy for RA that may help to diminish both joint inflammation and destruction.
[Show abstract][Hide abstract] ABSTRACT: Effects of the synthesizing parameters on the surface roughness and the contact angles of ZnO nanowire films were studied in this paper. ZnO nanowire films were synthesized with the hydrothermal method on glass substrates, and the synthesizing parameters include the concentrations of the growth solution and the seed layer solution, the growth time span as well as the temperature. Atomic force microscopy and scanning electron microscopy were employed respectively to characterize the surface and the profile roughness of ZnO nanowire films. The measurement results by atomic force microscopy were in agreement with that by scanning electron microscopy, hence the former was used for the investigation of aforementioned effects. Relationships between the synthesizing parameters, the surface roughness and the contact angles of ZnO nanowire films were established, revealing that the synthesizing parameters affected significantly not only the surface roughness but also the contact angles of ZnO nanowire films. The results can be used for batch fabrication of ZnO nanowire-based structures and these structures-based sensors in a wide variety of applications.
No preview · Article · Jun 2014 · Journal of Nanoscience and Nanotechnology
[Show abstract][Hide abstract] ABSTRACT: Fulminant hepatic failure is a severe clinical syndrome associated with a high rate of patient mortality. Recent studies have shown that in addition to its hematopoietic effect, erythropoietin (EPO) has multiple protective effects and exhibits antiapoptotic, antioxidant and anti‑inflammatory activities. The present study aimed to determine the hepatoprotective effect of EPO and to elucidate the underlying mechanisms using a D‑galactosamine (D‑GalN)/lipopolysaccharide (LPS)‑induced model of acute liver injury. Experimental groups of mice were administered with various doses of EPO (1,000, 3,000 or 10,000 U/kg, intraperitoneal) once per day for 3 days, prior to injection with D‑GalN (700 mg/kg)/LPS (10 µg/kg). Mice were sacrificed 8 h after treatment with D‑GalN/LPS. Liver function and histopathology, malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH‑Px) activities and EPO receptor (EPOR) and phosphatidylinositol 3‑kinase (PI3K) mRNA expression were evaluated. D‑GalN/LPS administration markedly induced liver injury, as evidenced by elevated levels of serum aminotransferases, as well as histopathological changes. Compared with the D‑GalN/LPS group, pretreatment with EPO significantly decreased the levels of aspartate aminotransferase, alanine aminotransferase and MDA, and increased the activities of SOD and GSH‑Px. Furthermore, the protective effects of EPO were paralleled by an upregulation in the mRNA expression of EPOR and PI3K. These data suggest that EPO can ameliorate D‑GalN/LPS‑induced acute liver injury by reducing oxidative stress and upregulating the mRNA expression of EPOR and PI3K.
Preview · Article · Apr 2014 · Molecular Medicine Reports
[Show abstract][Hide abstract] ABSTRACT: Rheumatoid arthritis (RA) is a systemic autoimmune disease mediated by T cells. Pro-inflammatory cytokine plays a critical role in the pathogenesis of RA. The aim of the present study was to investigate the effects of synthetic peptides (HP-R1, HP-R2 and HP-R3), derived from the sequence of 65-kD mycobacterial heat shock protein (HSP), on proliferation and cytokine secretion by peripheral blood mononuclear cells (PBMCs) of RA patients. PBMCs were obtained from RA patients and collected by Ficoll-Hypaque density centrifugation. PBMCs were treated with one of three synthetic peptides for 4h, after which the proliferation and cytokine production were determined. The effects of three peptides on proliferation of PBMCs were analyzed by a colorimetric cell proliferation assay (CCK-8 assay). Cytokine production was measured in culture supernatants using specific ELISA. The three peptides did not significantly affect the proliferation of PBMCs from healthy controls. Cell proliferation of RA patients was inhibited by three peptides. The production of tumor necrosis factor (TNF)-α was significantly inhibited by three peptides. HP-R1 and HP-R2 efficiently suppressed interferon (IFN)-γ secretion. Unlike the other two HP-Rs, HP-R2 increased the IL-4 level. The production of IL-10 was not significantly affected by any of the peptides. The present study suggests that the synthetic peptides derived from HSP65 display anti-proliferative and anti-inflammatory function and supports the potential use of the synthetic peptides as a therapeutic drug in RA patients. This article is protected by copyright. All rights reserved.
Preview · Article · Sep 2013 · Clinical and Experimental Pharmacology and Physiology
[Show abstract][Hide abstract] ABSTRACT: A hierarchical structure with a random rough surface superimposed on a
cylinder substrate was presented in this paper. The effect of the
characteristic parameters on the surface properties of this hierarchical
structure was summarized and partially simulated. The hierarchical
structure was generated by synthesizing ZnO nanowires with hydrothermal
method on an optical fiber core. Scanning electron microscopy
(SEM)-based characterization of the generated random rough surface on
the optical fiber core was employed to regulate and optimize
synthesizing parameters of ZnO nanowires. The relationship between the
synthesizing parameters and the desired morphology of the hierarchical
structure was established. The results can be used to form various
hierarchical structures to meet the requirements of different
applications in nanotechnology domain, including the wettability and the
adsorption of as well as the immobilization on different hierarchical
[Show abstract][Hide abstract] ABSTRACT: Liraglutide, a long-lasting glucagon‑like peptide‑1 analogue, has been used for the treatment of patients with type 2 diabetes mellitus since 2009. In this study, we investigated the anti-diabetic effects and mechanisms of action of liraglutide in a spontaneous diabetic animal model, using KK/Upj-Ay/J (KKAy) mice. The KKAy mice were divided into 2 groups, the liraglutide group (mice were treated with 250 µg/kg/day liraglutide) and the model group (treated with an equivalent amount of normal saline). C57BL/6J mice were used as the controls (treated with an equivalent amount of normal saline). The treatment period lasted 6 weeks. During this treatment period, fasting blood glucose (FBG) levels and the body weight of the mice were measured on a weekly basis. Our results revealed that liraglutide significantly decreased FBG levels, the area under the curve following a oral glucose tolerance test and insulin tolerance test, increased serum insulin levels, reduced homeostasis model assessment of insulin resistance and increased the insulin sensitivity index. Furthermore, liraglutide ameliorated glycometabolism dysfunction by increasing glycolysis via hexokinase and glycogenesis via pyruvate kinase activation. An ultrastructural examination of the pancreas revealed that liraglutide improved the damaged state of islet β cells and increased the number of insulin secretory granules. The real-time PCR results revealed that the gene expression of glucose transporter 4 (GLUT4) increased following treatment with liraglutide. Liraglutide also upregulated the protein expression of GLUT4 in liver tissue and skeletal muscle. Our results suggest that liraglutide ameliorates glycometabolism and insulin resistance in diabetic KKAy mice by stimulating insulin secretion, increasing glycogenesis and glycolysis and upregulating the expression of GLUT4.
Preview · Article · Jul 2013 · International Journal of Molecular Medicine
[Show abstract][Hide abstract] ABSTRACT: In this paper a Pt Archimedean-spiral interdigitated microelectrode with containing trenches was put forward, fabricated and characterized. Pt film with thickness 300nm was deposited by radio frequency (RF) magnetron sputtering on a Ti deposited n(100) Si substrate. On this Pt coated Si substrate a passivation layer of Si3N4 film with thickness 350nm was coated by plasma-enhanced chemical deposition (PECVD). The conventional photolithographic technique was used to pattern the Archimedean-spiral interdigitated microelectrodes with containing trenches, the contact tracks and the bond pads. Scanning electron microscopy (SEM) images along with filtration, line edge detection and fit operators of Mat-Lab software were employed to characterize the quality of Pt interdigitated microelectrodes. Cyclic voltammetry was performed on a CHI660D electrochemical workstation and the results indicated the critical dimension (CD) of Pt Archime-dean-spiral interdigitated microelectrode with containing trenches was within sub-micrometer range and the microelectrode can be used as the key sensing device in electrochemistry, biology, medicine and environmental monitoring.
[Show abstract][Hide abstract] ABSTRACT: In this paper Au ring microelectrodes are fabricated and characterized. With an optical fibre core as a substrate Au film with thickness 300nm was coated by an electron beam evaporation system, then on this Au coated substrate a parylene passivation layer was deposited, forming the desired Au ring microelectrode. Scanning electron microscopy (SEM) was used to characterize the quality of the deposited films and the adhesion at the interfaces. With a CHI660D electrochemical workstation the electrochemical characterizations were performed at room temperature in a conventional three-electrode system. Cyclic voltammograms as a function of scan rate were sigmoidal form, a typical electrochemical response of microelectrodes. AC impedance frequency spectrum of the fabricated Au ring microelectrode was also obtained in a reversible system, and good agreement was found with the Randels-type equivalent circuit.
[Show abstract][Hide abstract] ABSTRACT: Vagus nerve stimulation (VNS) has been shown to improve left ventricular function and survival in rats with acute myocardial infarction (AMI), and this maneuver has also been adopted clinically for the treatment of patients with chronic heart failure (CHF). Recent in vitro and in vivo studies have suggested that VNS can modulate the level of pro-inflammatory factors. Despite the beneficial effects of VNS, the stimulation parameters for obtaining favorable outcomes appear highly variable. To optimize VNS parameters, we set up different stimulation protocols with different pulse width (1-2 ms), frequency (1-6 Hz), voltage (1-6 V) and duration (40-240 min) of VNS by uniform design (UD). Rats were divided into seven groups with (Group1-Group6) or without VNS (MI group). Our results demonstrate that (1) the parameter sets in Group1, Group2 and Group3 yield the best post-MI protection by VNS, while the protective role were not observed in Group4, Group5 and Group6; (2) baroreflex sensitivity and the α7 nicotinic acetylcholine receptor level were also increased in Group1, Group2 and Group3. (3) the parameter set in Group1 (G1:1 ms, 2 Hz, 3 V, 240 min) is judged the most optimal parameter in this study as rats in this group not only showed a reduced myocardial injury with better-preserved cardiac function compared with other groups, more important, but also exhibited minimal heart rate (HR) reduction. (4) the duration of VNS plays an important role in determining the protection effect of VNS. In conclusion, VNS displays a beneficial role in Group1, Group2 and Group3. Of note, the parameter set in Group1 provides the most optimal cardioprotective effect. These results may provide insight into development of novel treatment for ischemic heart diseases.
[Show abstract][Hide abstract] ABSTRACT: To study the association between the single nucleotide polymorphisms (SNPs) in FXYD6 gene and schizophrenia in a family-trios population.
Six SNPs (rs10790212, rs11544201, rs555577, rs1815774, rs4938446 and rs497768) in the FXYD6 gene were genotyped by allele-specific PCR method in 101 nuclear families, and transmission disequilibrium test (TDT) was performed.
SNPs rs10790212 and rs11544201 showed significant association with schizophrenia (P<0.05). Furthermore, significant association of schizophrenia with the haplotype rs10790212-rs11544201 was found (P<0.05).
FXYD6 gene might play an important role in schizophrenia susceptibility and functional analysis of FXYD6 are needed.
No preview · Article · Oct 2011 · Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics