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991.
992.
Anti‐Inflammatory Effect of Ascochlorin in LPS‐Stimulated RAW 264.7 Macrophage Cells Is Accompanied With the Down‐Regulation of iNOS,COX‐2 and Proinflammatory Cytokines Through NF‐κB,ERK1/2, and p38 Signaling Pathway 下载免费PDF全文
993.
S. MAHESH M. LEELAMBIKA MD JAHEER A. M. ANITHAKUMARI N. SATHYANARAYANA 《Journal of genetics》2016,95(1):35-44
Mucuna pruriens is a well-recognized agricultural and horticultural crop with important medicinal use. However, antinutritional factors in seed and adverse morphological characters have negatively affected its cultivation. To elucidate the genetic control of agronomic traits, an intraspecific genetic linkage map of Indian M. pruriens has been developed based on amplified fragment length polymorphism (AFLP) markers using 200 F 2 progenies derived from a cross between wild and cultivated genotypes. The resulting linkage map comprised 129 AFLP markers dispersed over 13 linkage groups spanning a total distance of 618.88 cM with an average marker interval of 4.79 cM. For the first time, three QTLs explaining about 6.05–14.77% of the corresponding total phenotypic variation for three quantitative (seed) traits and, eight QTLs explaining about 25.96% of the corresponding total phenotypic variation for three qualitative traits have been detected on four linkage groups. The map presented here will pave a way for mapping of genes/QTLs for the important agronomic and horticultural traits contrasting between the parents used in this study. 相似文献
994.
KCa3.1 upregulation preserves endothelium‐dependent vasorelaxation during aging and oxidative stress 下载免费PDF全文
Shinkyu Choi Ji Aee Kim Hai‐yan Li Kyong‐Oh Shin Goo Taeg Oh Yong‐Moon Lee Seikwan Oh Yael Pewzner‐Jung Anthony H. Futerman Suk Hyo Suh 《Aging cell》2016,15(5):801-810
Endothelial oxidative stress develops with aging and reactive oxygen species impair endothelium‐dependent relaxation (EDR) by decreasing nitric oxide (NO) availability. Endothelial KCa3.1, which contributes to EDR, is upregulated by H2O2. We investigated whether KCa3.1 upregulation compensates for diminished EDR to NO during aging‐related oxidative stress. Previous studies identified that the levels of ceramide synthase 5 (CerS5), sphingosine, and sphingosine 1‐phosphate were increased in aged wild‐type and CerS2 mice. In primary mouse aortic endothelial cells (MAECs) from aged wild‐type and CerS2 null mice, superoxide dismutase (SOD) was upregulated, and catalase and glutathione peroxidase 1 (GPX1) were downregulated, when compared to MAECs from young and age‐matched wild‐type mice. Increased H2O2 levels induced Fyn and extracellular signal‐regulated kinases (ERKs) phosphorylation and KCa3.1 upregulation. Catalase/GPX1 double knockout (catalase?/?/GPX1?/?) upregulated KCa3.1 in MAECs. NO production was decreased in aged wild‐type, CerS2 null, and catalase?/?/GPX1?/? MAECs. However, KCa3.1 activation‐induced, NG‐nitro‐l ‐arginine‐, and indomethacin‐resistant EDR was increased without a change in acetylcholine‐induced EDR in aortic rings from aged wild‐type, CerS2 null, and catalase?/?/GPX1?/? mice. CerS5 transfection or exogenous application of sphingosine or sphingosine 1‐phosphate induced similar changes in levels of the antioxidant enzymes and upregulated KCa3.1. Our findings suggest that, during aging‐related oxidative stress, SOD upregulation and downregulation of catalase and GPX1, which occur upon altering the sphingolipid composition or acyl chain length, generate H2O2 and thereby upregulate KCa3.1 expression and function via a H2O2/Fyn‐mediated pathway. Altogether, enhanced KCa3.1 activity may compensate for decreased NO signaling during vascular aging. 相似文献
995.
996.
Intratympanic (IT) steroid treatment is one of the most widely used and effective treatments for inner ear disorders such as sudden sensorineural hearing loss (SNHL). However, a clear mechanism of IT steroids in inner ear recovery has not yet been revealed. Therefore, we investigated proteome changes in extracted human perilymph after steroid treatment. In this study, we applied a tandem mass spectrometry (MS/MS)-based proteomics approach to discover global proteome changes by comparing human perilymph after steroid treatment with non-treated perilymph group. Using liquid chromatography-MS/MS analysis, we selected 156 differentially expressed proteins (DEPs) that were statistically significant according to Student's t-test. Functional annotation analysis showed that upregulated proteins after steroid treatment are related to apoptosis signaling, as well as reactive oxygen species (ROS) and immune responses. The protein–protein interaction (PPI) clusters the proteins associated with these processes and attempts to observe signaling circuitry, which mediates cellular response after IT steroid treatments. Moreover, we also considered the interactome analysis of DEPs and observed that those with high interaction scores were categorized as having equivalent molecular functions (MFs). Collectively, we suggest that DEPs and interacting proteins in human perilymph after steroid treatment would inhibit the apoptotic and adaptive immune processes that may lead to anti-inflammatory effects. 相似文献
997.
Wei W Zeve D Suh JM Wang X Du Y Zerwekh JE Dechow PC Graff JM Wan Y 《Molecular and cellular biology》2011,31(23):4706-4719
Wnt/β-catenin signaling is a critical regulator of skeletal physiology. However, previous studies have mainly focused on its roles in osteoblasts, while its specific function in osteoclasts is unknown. This is a clinically important question because neutralizing antibodies against Wnt antagonists are promising new drugs for bone diseases. Here, we show that in osteoclastogenesis, β-catenin is induced during the macrophage colony-stimulating factor (M-CSF)-mediated quiescence-to-proliferation switch but suppressed during the RANKL-mediated proliferation-to-differentiation switch. Genetically, β-catenin deletion blocks osteoclast precursor proliferation, while β-catenin constitutive activation sustains proliferation but prevents osteoclast differentiation, both causing osteopetrosis. In contrast, β-catenin heterozygosity enhances osteoclast differentiation, causing osteoporosis. Biochemically, Wnt activation attenuates whereas Wnt inhibition stimulates osteoclastogenesis. Mechanistically, β-catenin activation increases GATA2/Evi1 expression but abolishes RANKL-induced c-Jun phosphorylation. Therefore, β-catenin exerts a pivotal biphasic and dosage-dependent regulation of osteoclastogenesis. Importantly, these findings suggest that Wnt activation is a more effective treatment for skeletal fragility than previously recognized that confers dual anabolic and anti-catabolic benefits. 相似文献
998.
Facilitated Neurogenesis in the Developing Hippocampus After Intake of Theanine,an Amino Acid in Tea Leaves,and Object Recognition Memory 总被引:1,自引:0,他引:1
Takeda A Sakamoto K Tamano H Fukura K Inui N Suh SW Won SJ Yokogoshi H 《Cellular and molecular neurobiology》2011,31(7):1079-1088
Theanine, γ-glutamylethylamide, is one of the major amino acid components in green tea. In this study, cognitive function
and the related mechanism were examined in theanine-administered young rats. Newborn rats were fed theanine through dams,
which were fed water containing 0.3% theanine, and then fed water containing 0.3% theanine after weaning. Theanine level in
the brain was under the detectable limit 6 weeks after the start of theanine administration. Theanine administration did not
influence locomotor activity in the open-field test. However, rearing behavior was significantly increased in theanine-administered
rats, suggesting that exploratory activity is increased by theanine intake. Furthermore, object recognition memory was enhanced
in theanine-administered rats. The increase in exploratory activity in the open-field test seems to be associated with the
enhanced object recognition memory after theanine administration. On the other hand, long-term potentiation (LTP) induction
at the perforant path-granule cell synapse was not changed by theanine administration. To check hippocampal neurogenesis,
BrdU was injected into rats 3 weeks after the start of theanine administration, and brain-derived neurotropic factor (BDNF)
level was significantly increased at this time. Theanine intake significantly increased the number of BrdU-, Ki67-, and DCX-labeled
cells in the granule cell layer 6 weeks after the start of theanine administration. This study indicates that 0.3% theanine
administration facilitates neurogenesis in the developing hippocampus followed by enhanced recognition memory. Theanine intake
may be of benefit to the postnatal development of hippocampal function. 相似文献
999.
The vast majority of extant birds possess highly differentiated Z and W sex chromosomes. Nucleotide sequence data from gametologs (homologs on opposite sex chromosomes) suggest that this divergence occurred throughout early bird evolution via stepwise cessation of recombination between identical sex chromosomal regions. Here, we investigated avian sex chromosome differentiation from a novel perspective, using retroposon insertions and random insertions/deletions for the reconstruction of gametologous gene trees. Our data confirm that the CHD1Z/CHD1W genes differentiated in the ancestor of the neognaths, whereas the NIPBLZ/NIPBLW genes diverged in the neoavian ancestor and independently within Galloanserae. The divergence of the ATP5A1Z/ATP5A1W genes in galloanserans occurred independently in the chicken, the screamer, and the ancestor of duck-related birds. In Neoaves, this gene pair differentiated in each of the six sampled representatives, respectively. Additionally, three of our investigated loci can be utilized as universal, easy-to-use independent tools for molecular sexing of Neoaves or Neognathae. 相似文献
1000.
Phospholipase C-η1 (PLC-η1) is the most recently identified PLC isotype and is primarily expressed in nerve tissue. However, its functional role is unclear. In the present study, we report for the first time that PLC-η1 acts as a signal amplifier in G protein-coupled receptor (GPCR)-mediated PLC and Ca2+ signaling. Short-hairpin RNA (shRNA)-mediated knockdown of endogenous PLC-η1 reduced lysophosphatidic acid (LPA)-, bradykinin (BK)-, and PACAP-induced PLC activity in mouse neuroblastoma Neuro2A (N2A) cells, indicating that PLC-η1 participates in GPCR-mediated PLC activation. Interestingly, ionomycin-induced PLC activity was significantly decreased by PLC-η1, but not PLC-η2, knockdown. In addition, we found that intracellular Ca2+ source is enough for PLC-η1 activation. Furthermore, the IP3 receptor inhibitor, 2-APB, inhibited LPA-induced PLC activity in control N2A cells, whereas this effect was not observed in PLC-η1 knockdown N2A cells, suggesting a pivotal role of intracellular Ca2+ mobilization in PLC-η1 activation. Finally, we found that LPA-induced ERK1/2 phosphorylation and expression of the downstream target gene, krox-24, were significantly decreased by PLC-η1 knockdown, and these knockdown effects were abolished by 2-APB. Taken together, our results strongly suggest that PLC-η1 is activated via intracellular Ca2+ mobilization from the ER, and therefore amplifies GPCR-mediated signaling. 相似文献