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991.
Aims
The multiple physiological characterizations of exendin-4 make it as a promising drug candidate for the therapy of type 2 diabetes. Although the longer biological half-life offered the exendin-4 with excellent therapeutic potentials for the clinical utility of type 2 diabetes than glucagon-like peptide-1, the exendin-4 still did not free from the inconveniently frequent injections. Therefore, there are increasing requirements for the long-acting exendin-4.Methods
Pp1 regard as a novel exendin-4 protecting peptide, which are predicted to have the ability of increasing the stabilization of exendin-4 in vivo. Protecting peptide is able to form stable complex by non-covalent interaction with human exendin-4.Results
In this study, the stability of the exendin-4/Pp1 complex was investigated, and the physiological functions of it were analyzed. Results indicated that exendin-4/Pp1 complex remarkably raised the stabilization of exendin-4 in vivo; it also showed better glucose tolerance and higher HbA1c reduction than exendin-4 which was utilized chronically in rodents.Conclusion
Based upon these results, it is suggested that an exendin-4/Pp1 complex might be utilized as a potent anti-diabetic drug in the treatment of type 2 diabetes mellitus. 相似文献992.
Peng X Gong F Xie G Zhao Y Tang M Yu L Tong A 《Molecular and cellular biochemistry》2011,351(1-2):233-241
This study aimed to explore the mechanism of adriamycin resistance in human chronic myelogenous leukemia cells. Proteomic approach was utilized to compare and identify differentially expressed proteins between human chronic myelogenous leukemia K562 cells and their adriamycin-resistant counterparts. The differentially expressed proteins were analyzed by 2-DE (two-dimensional gel electrophoresis), and protein identification were performed on ESI-Q-TOF MS/MS instrument. Out of the 35 differentially expressed proteins between the two cell lines, 29 were identified and grouped into 10 functional classes. Most of identified proteins were related to the categories of metabolism (24%), proteolysis (13%), signal transduction (21%) and calcium ion binding (6%), suggesting that alterations of those biological processes might be involved in adriamycin resistance of K562 cells. We believe this study may provide some clues to a better understanding of the molecular mechanisms underlying adriamycin resistance. 相似文献
993.
994.
Han N Shi Z Zhang K Gao X Zheng Z Gong P Guo Y Huang S Zhang F 《Cellular and molecular neurobiology》2011,31(5):695-700
Discs-large-related 3 (DLG3), a member of the membrane-associated guanylate kinases (MAGUKs) protein family, playing an important
role in regulating NMDA signal pathway and contributing to synaptic plasticity, may have an influence on the susceptibility
of non-syndromic mental retardation (NSMR). To investigate the possible genetic contribution of DLG3 gene to the NSMR of Chinese Han population, we performed an association study of 556 subjects (118 NSMR, 116 borderline NSMR,
and 322 controls in 275 males and 281 females) from Qin-Ba mountain region of Shaanxi province in the northwest of China by
five common SNPs in the gene. The results showed that there was no positive association between the genetic variations of
DLG3 and NSMR. In conclusion, the results of this study indicated that DLG3 did not associate with NSMR in Chinese Han population; however, further studies are needed. 相似文献
995.
Gong P Zhang F Lei X Wu X Chen D Zhang W Zhang K Zheng A Gao X 《Cellular and molecular neurobiology》2011,31(4):519-526
Reasoning skill is an advanced cognitive ability which is needed for drawing inferences from given information. It is well
known that the ability depends on the neural network of the frontal and parietal brain regions. In this study, we hypothesized
that some genes involved in neurotransmitter systems were related to reasoning skill. To confirm this hypothesis, we examined
the effects of 13 genes (BDNF, NRSF, COMT, DBH, DRD
2
, DRD
3
, DAT
1
, MAOA, GRM
1, GRIN2B, TPH
2
, 5-HT
2A
, and 5-HT
6
) in neurotransmitter systems on the non-verbal reasoning and verbal reasoning skills. The results indicated there were on
significant effects of the 17 functional variants of these genes on the performance of non-verbal reasoning and verbal analogical
reasoning skills (χ2 > 3.84, df = 1, P > 0.05). This study suggests that some of the functional variations in BDNF, COMT, DBH, DRD
2
, DRD
3
, MAOA, 5-HT
2A
, 5-HT
6
, GRM
1
, and GRIN2B have no observable effects on the certain reasoning skills in a young healthy Chinese Han population. 相似文献
996.
Heparan sulfate (HS), a polysaccharide ubiquitously expressed in animals, is essential for development and homeostasis. Degradation of HS by heparanase, an endoglucuronidase, may affect pathophysiological function. Expression of the heparanase gene has been found elevated in a number of pathological conditions. The goal of this work was to investigate the impact of heparanase on expression of other genes. DNA microarray analysis revealed that 1, 042 genes in the cortex and 1,039 genes in the thalamus are up- or down-regulated more than 2-fold in mouse brain overexpresssing human heparanase. Of these genes, two of the early growth response genes, Egr1 and Egr2, are substantially upregulated in the cortex, but essentially unchanged in the thalamus. RT-PCR analysis demonstrated a significant increase of Egr2, but a minor increase of Egr1, in human embryonic kidney cells stably overexpressing heparanase. The upregulated expression of Egr genes is also observed in hepatoma cells with upregulated expression of heparanase. Earlier studies reported that Egr1 induced heparanase expression; our findings suggest a possible reciprocal regulation of Egr and heparanase expression. Furthermore, overexpression of heparanase influenced expression of most genes involved in heparan sulfate proteoglycan biosynthesis, albeit to a different degree in the cortex and thalamus of the transgenic mice. 相似文献
997.
We present a study on the rupture behavior of single NIH 3T3 mouse fibroblasts under tension using micropipette aspiration. Membrane rupture was characterized by breaking and formation of an enclosed membrane linked to a tether at the cell apex. Three different rupture modes, namely: single break, initial multiple breaks, and continuous multiple breaks, were observed under similar loading condition. The measured mean tensile strengths of plasma membrane were 3.83 ± 1.94 and 3.98 ± 1.54mN/m for control cells and cells labeled with TubulinTracker, respectively. The tensile strength data was described by Weibull distribution. For the control cells, the Weibull modulus and characteristic strength were 1.86 and 4.40 mN/m, respectively; for cells labeled with TubulinTracker, the Weibull modulus and characteristic strength were 2.68 and 4.48 mN/m, respectively. Based on the experimental data, the estimated average transmembrane proteins-lipid cleavage strength was 2.64 ± 0.64 mN/m. From the random sampling of volume ratio of transmembrane proteins in cell membrane, we concluded that the Weibull characteristic of plasma membrane strength was likely to be originated from the variation in transmembrane proteins-lipid interactions. 相似文献
998.
Chronic exposure to saturated fatty acids can cause insulin resistance. However, the acute effects of fatty acids are not clear and need to be elucidated because plasma fatty acid concentrations fluctuate postprandially. Here, we present the acute effects of palmitate (PA) on skeletal muscle cells and their underlying molecular mechanisms. Immuno-fluorescence results showed that PA rapidly induced GLUT4 translocation and stimulated glucose uptake in rat skeletal muscle cell line L6. Phosphorylation of AMP-activated protein kinase (AMPK), Akt, and extracellular signal-related kinase1/2 (ERK1/2) was enhanced by PA in a time-dependent manner. Cell surface-bound PA was sufficient to stimulate Akt phosphorylation. The inhibitors of PI3 kinase (PI3K), AMPK, Akt, and ERK1/2 could decrease PA-induced glucose uptake, and PI3K inhibitor decreased AMPK, Akt, and ERK1/2 phosphorylation. Weakening AMPK activity reduced phosphorylation of Akt but not ERK1/2, and Akt inhibitor could not affect ERK1/2 activation either. Meanwhile, ERK1/2 inhibitors had no effect on Akt phosphorylation. Taken together, our data suggest that PA-mediated glucose uptake in skeletal muscle cells may be stimulated by the binding of PA to cell surface and followed by PI3K/AMPK/Akt and PI3K/ERK1/2 pathways independently. 相似文献
999.
Cerebral dopamine neurotrophic factor (CDNF) is a novel evolutionary conserved protein which can protect and restore the function of dopaminergic neurons in the rat model of Parkinson's disease, suggesting that CDNF might be beneficial for the treatment of Parkinson's disease. CDNF is widely expressed in neurons in several brain regions including cerebral cortex, hippocampus, substantia nigra, striatum and cerebellum. Human CDNF is glycosylated and secreted from transiently transfected cells; however, the mechanism underlying CDNF secretion is currently unclear. In this study, we found that CDNF could be secreted primarily via the regulated secretion pathway in PC12 cells. The glycosylation of CDNF is not required for its secretion. Moreover, we identified two key subdomains in CDNF which are important for its intracellular localization and secretion. Disrupting helix-1 of CDNF significantly reduces its constitutive and regulated secretion and the helix-1 mutant is retained in the endoplasmic reticulum. Although helix-7 mutation only decreases CDNF regulated secretion and has no effect on its constitutive secretion, which is further supported by the reduction in co-localization of helix-7 mutant with secretory granules. In all, these findings will advance our understanding of the molecular mechanism of CDNF trafficking and secretion. 相似文献
1000.
Hong‐Sil Park Youngja Jung Hong‐Seog Park Mi Sook Hwang Eun‐Jeong Park Yong‐Gun Gong 《Journal of phycology》2011,47(4):821-828
Temperature is one of the major environmental factors that affect the distribution, growth rate, and life cycle of intertidal organisms, including red algae. In an effort to identify the genes involved in the high‐temperature tolerance of Porphyra, we generated 3,979 expression sequence tags (ESTs) from gametophyte thalli of P. seriata Kjellm. under normal growth conditions and high‐temperature conditions. A comparison of the ESTs from two cDNA libraries allowed us to identify the high temperature response (HTR) genes, which are induced or up‐regulated as the result of high‐temperature treatment. Among the HTRs, HTR2 encodes for a small polypeptide consisting of 144 amino acids, which is a noble nuclear protein. Chlamydomonas expressing the Porphyra HTR2 gene shows higher survival and growth rates than the wild‐type strain after high‐temperature treatment. These results suggest that HTR2 may be relevant to the tolerance of high‐temperature stress conditions, and this Porphyra EST data set will provide important genetic information for studies of the molecular basis of high‐temperature tolerance in marine algae, as well as in Porphyra. 相似文献