Search

A comprehensive understanding of the integrative nature of the molecular network in thrombosis would be very helpful to develop multicomponent and multitarget antithrombosis drugs for use in traditional Chinese medicine (TCM). This paper attempts to comprehensively map the molecular network in thrombosis by combining platelet signaling, the coagulation cascade, and natural clot dissolution systems and to analyze the topological characteristics of the network, including the centralities of nodes, network modules, and network robustness. The results in this research advance understanding of functions of proteins in the thrombosis network and provide a reference for predicting potential therapeutic antithrombotic targets and evaluating their influence on the network. [ABSTRACT FROM AUTHOR]

Compares the effects of estrogen (E) on the hyperactivity induced by methylenedioxymethamphetamine with E effects on cocaine-evoked hyperactivity in female rats. Reason behind the differential effects of E on hyperactivity; Effects of E2 on spontaneous activity in ovariectomized (OVX) rats; Influence of E2 on dose-response to cocaine in OVX rats.

The effects in the brain of selective estrogen receptor modulators (SERMs) such as tamoxifen and raloxifene have not yet been fully elucidated. Based upon the hypothesis that serotonin (5-HT)-steroid hormone interactions are important in mood regulation, we have compared six SERMs (tamoxifen, raloxifene, levormeloxifene, NNC 45-0781, NNC 45-0320, NNC 45-1506) with 17β-estradiol (E[sub 2] ) in terms of their ability to regulate mRNA levels of estrogen receptor (ER)α, ERβ, 5-HT[sub 1A] receptor, and 5-HT reuptake transporter (SERT) in the midbrain, amygdala, and hypothalamus of ovariectomized (OVX) rats. Female rats (n = 6/group, 8 groups total) were OVX and allowed to recover for 2 weeks. During the third post-OVX week, rats were injected subcutaneously with E[sub 2] (0.1 mg/kg) or one of the SERMs (5 mg/kg) once per day for 7 days. Twenty-four hours after the last injection, tissue was collected for the determination of mRNA levels by ribonuclease protection assay (RPA). E[sub 2] treatment significantly decreased mRNA levels for ERα, ERβ, and SERT in midbrain and ERα in hypothalamus. Tamoxifen increased ERβ mRNA levels in hypothalamus, while raloxifene increased ERβ mRNA levels in amygdala. NNC 45-0320 decreased ERα mRNA in hypothalamus and decreased ERβ mRNA in amygdala. These results suggest that while SERMs are not full estrogen receptor agonists in the brain, the agonist/antagonist profiles for individual SERMs may differ among brain areas. This raises the possibility of developing new SERMs for selective functions in specific brain areas.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Background: The prevalence of atrial fibrillation (AF) and the frequency cardioversion of AF postoperatively are different in different forms of mitral valve disease. We hypothesized that these differences would relate to different extent of histopathological characteristics and oxidative injury in different forms of mitral valve diseases. Methods: Left atrial appendages were obtained from 24 patients of mitral valve disease with or without AF undergoing mitral valve surgery. Control data were obtained from left appendages of 4 persons in normal sinus rhythm (SR) died of traffic accident. Histopathology, immunohistochemistry, Western blotting and enzyme kinetics examination were performed to assess the extent of histopathological characteristics and oxidative injury. Results: The average cross-sectional diameter of atrial myocyte of mitral stenosis (MS)+AF, MS+SR, mitral regurgitation (MR)+AF, MR+SR and control was 25.62±7.56 μm, 20.20±9.34 μm, 21.69±7.00 μm, 13.93±4.32 μm and 9.81±2.34 μm, respectively. Significantly statistical difference was found between each group (P<.05). Increased degree of atrial interstitial fibrosis was seen both in MS and MR with AF patients compared to other groups (P<.05), and the extent of fibrosis was more remarkable in MR patients compared to MS patients (P<.05). The extent of 3-nitrotyrosine (3-NT) immunoreactivity significantly increased in the patients with MS and AF compared to those of MR and AF (P<.05), and the immunoprevalence of 3-NT was significantly increased in patients of MS and SR compared to those of MR and SR (P<.05). Correlation analysis demonstrated a negative correlation between creatine kinase (CK) activity and extent of 3-NT immunoreactivity in atrial tissues (r=−0.382, P<.05). Significant decreases in CK activity were observed in myocardium from all patients of mitral valve disease with or without AF compared to controls (P<.05). Western blotting demonstrating an increased prevalence of 3-NT formation in CK-MM was detected compared to control group (P<.05). Correlation analysis demonstrated a negative correlation between CK-MM activity and extent of CK-MM tyrosine nitration (r=−0.446, P<.05). Conclusions: In different forms of mitral valve disease with different cardiac rhythm, the extent of histopathological characteristics and oxidative injury are different. Histopathological characteristics and oxidative injury not only relate to mitral valve disease but also relate to the development and sustain of AF. [Copyright &y& Elsevier]

Cataract is a major cause of blindness worldwide, its complicated and unclear etiopathogenesis limit effective therapy. Here, we found that Yap, a downstream effector of the Hippo pathway, is specifically expressed in lens epithelial cells and Yap conditional knockout (cKO) in the lens leads to cataract. Histologically, Yap deficient lens show fewer epithelial cells, retention of nuclei and accumulation of morgagnian globules in the transitional zone and the posterior area. Mechanistically, GFAP-mediated Yap cKO leads to the reduced proliferation of epithelial cells, delayed fiber cell denucleation and increased cellular senescence in lens. Further RNA profiling analysis reveals Yap cKO results in a significant alteration in gene transcription that is involved in eye development, lens structure, inflammation, cellular proliferation and polarity. Collectively, our data reveal a novel function of Yap in the lens and links Yap deficiency with the development of cataract, making Yap a promising target for cataract therapy. [ABSTRACT FROM AUTHOR]

It is well known that Notch1 signaling plays a crucial role in embryonic neural development and adult neurogenesis. The latest evidence shows that Notch1 also plays a critical role in synaptic plasticity in mature hippocampal neurons. So far, deeper insights into the function of Notch1 signaling during the different steps of adult neurogenesis are still lacking, and the mechanisms by which Notch1 dysfunction is associated with brain disorders are also poorly understood. In the current study, we found that Notch1 was highly expressed in the adult-born immature neurons in the hippocampal dentate gyrus. Using a genetic approach to selectively ablate Notch1 signaling in late immature precursors in the postnatal hippocampus by cross-breeding doublecortin (DCX)+ neuron-specific proopiomelanocortin (POMC)-a Cre mice with floxed Notch1 mice, we demonstrated a previously unreported pivotal role of Notch1 signaling in survival and function of adult newborn neurons in the dentate gyrus. Moreover, behavioral and functional studies demonstrated that POMC-Notch1-/- mutant mice showed anxiety and depressive-like behavior with impaired synaptic transmission properties in the dentate gyrus. Finally, our mechanistic study showed significantly compromised phosphorylation of cAMP response element-binding protein (CREB) in Notch1 mutants, suggesting that the dysfunction of Notch1 mutants is associated with the disrupted pCREB signaling in postnatally generated immature neurons in the dentate gyrus. [ABSTRACT FROM AUTHOR]

The senescence-accelerated mouse prone 8 (SAMP8) strain is considered a robust experimental model for developing preventative and therapeutic treatments for Alzheimer's disease (AD), a neurodegenerative disease which cannot be effectively prevented, halted, or cured. Our previous studies showed that LW-AFC, a new formula derived from the classical traditional Chinese medicinal prescription Liuwei Dihuang decoction, ameliorates cognitive deterioration in PrP-hAβPPswe/PS1ΔE9 transgenic mice and SAMP8 mice. This study aims to investigate the mechanism that mediates how LW-AFC improves cognitive deficit on the basis of the transcriptome. We conducted a genome-wide survey of gene expression in the hippocampus in mice from the senescence accelerated mouse resistant 1 (SAMR1) strain, from SAMP8 and from LW-AFC treated SAMP8. The results showed that LW-AFC reversed the transcriptome in the hippocampus of SAMP8 mice. The specific investigation of altered gene expression in subtypes defined by cognitive profiles indicated that the systemic lupus erythematosus pathway, spliceosomes, amyotrophic lateral sclerosis, and the insulin signaling were involved in the improvement of cognitive ability by LW-AFC. The expression of genes Enpp2, Etnk1, Epdr1, and Gm5900 in the hippocampus were correlated with that of LW-AFC's ameliorating cognitive impairment in SAMP8 mice. Because LW-AFC is composed of polysaccharides, glycosides, and oligosaccharides, we infer that LW-AFC has direct or indirect effects on altering gene expressions and regulating pathways in the hippocampus of SAMP8 mice. These data are helpful for the enhanced identification of LW-AFC as new therapeutic modalities to AD. [ABSTRACT FROM AUTHOR]

Glycosylation is one of the most common eukaryotic post-translational modifications, and aberrant glycosylation has been linked to many diseases. However, glycosylation and glycome analysis is a significantly challenging task. Although several lines of evidence have indicated that protein glycosylation is defective in Alzheimer's disease (AD), only a few studies have focused on AD glycomics. The etiology of AD is unclear and there are no effective disease-modifying treatments for AD. In this study, we found that the object recognition memory, passive avoidance, and spatial learning and memory of senescence-accelerated mouse prone 8 (SAMP8) strain, an AD animal model, were deficient, and LW-AFC, which was prepared from the traditional Chinese medicine prescription Liuwei Dihuang decoction, showed beneficial effects on the deterioration of cognitive capability in SAMP8 mice. Forty-three and 56 N-glycan were identified in the cerebral cortex and serum of SAMP8 mice, respectively. The N-glycan profile in SAMP8 mice was significantly different from that of senescence accelerated mouse resistant 1 (SAMR1) strains, the control of SAMP8 mice. Treatment with LW-AFC modulated the abundance of 21 and 6 N-glycan in the cerebral cortex and serum of SAMP8 mice, respectively. The abundance of (Hex)3(HexNAc)5(Fuc)1(Neu5Ac)1 and (Hex)2(HexNAc)4 decreased in the cerebral cortex and serum of SAMP8 mice compared with SAMR1 mice, decreases that were significantly correlated with learning and memory measures. The administration of LW-AFC could reverse or increase these levels in SAMP8 mice. These results indicated that the effects of LW-AFC on cognitive impairments in SAMP8 mice might be through modulation of N-glycan patterns, and LW-AFC may be a potential anti-AD agent. [ABSTRACT FROM AUTHOR]

A series of poly(ADP-ribose)polymerase (PARP)-1 inhibitors containing a novel scaffold, the 1H-thieno[3,4-d]imidazole-4-carboxamide moiety, was designed and synthesized. These efforts provided some compounds with relatively good PARP-1 inhibitory activity, and among them, 16l was the most potent one. Cellular evaluations indicated that the anti-proliferative activities of 16g, 16i, 16j and 16l against BRCA-deficient cell lines were similar to that of olaparib, while the cytotoxicities of 16j and 16l toward human normal cells were lower. In addition, ADMET prediction results indicated that these compounds might possess more favorable toxicity and pharmacokinetic properties. This study provides a basis for our further investigation. [ABSTRACT FROM AUTHOR]

Objective: Synaptic vesicles (SVs) are essential organelles that store and release neurotransmitters within presynaptic terminals. Isolated and purified SVs can be used to investigate their biochemical, structural, and functional characteristics, to elucidate the neurotransmission process. This paper describes a method for obtaining purified and functional SVs. Methods: SVs were isolated from the brains of Sprague--Dawley rats using differential and density-gradient centrifugation. Their morphology was observed with electron microscopy. The amount of protein in the SV fraction was determined by the Bradford assay. Specific SVs were purified using magnetic beads and immunoisolation, and immunoblot assays were used to measure levels of SV markers. SV glutamate uptake was assayed by radiotracer efflux assays. Results: A total of 10 mg SV protein was purified from 22 g of hippocampal and cerebral cortex tissue. The purified SVs were homogenous small spherical vesicles with a diameter of ~40 nm as assessed with electron microscopy, and they were rich in the protein SV protein 2 (SV2), vesicular glutamate transporter 1 (VGLUT1), and VGLUT2, but not VGLUT3. The SV2-specific SVs obtained by immunoadsorption with nearly 83% yield could uptake L- glutamate. Rose Bengal, a VGLUT inhibitor, prevented SV2-specific SVs from taking-up L- glutamate. Conclusions: This study describes a successful method for obtaining purified SVs that retained their structure and ability to perform their primary in vivo functions. These SVs can be used to understand SV composition and function, and the process of neurotransmitter release, and to evaluate therapeutic drugs for nervous system diseases. [ABSTRACT FROM AUTHOR]

Whole-cell currents in cultured hippocampal neurons were recorded to investigate the effects of SO-3, a new O-superfamily conopeptide derived from Conus striatus, on voltage-sensitive channels.SO-3 had no effect on voltage-sensitive sodium currents, delayed rectifier potassium currents, and transient outward potassium currents.Similar to the selective N-type calcium channel blocker ω-conotoxin MVIIA (MVIIA), SO-3 could concentration-dependently inhibit the high voltage-activated (HVA) calcium currents (ICa).MVIIA(3 μM), 10 μM nimodipine, and 0.5 μM ω-agatoxin IVA (Aga) could selectively block the N-, L-, and P/Q-type ICa, which contributed ∼32, ∼38, and ∼21% of the HVA currents in hippocampal neurons, respectively. About 31% of the total HVA currents were inhibited by 3 μM SO-3. SO-3 (3 μM) and 3 μM MVIIA inhibited the overlapping components of HVA currents, whereas no overlapping component was inhibited by 3 μM SO-3 and 10 μM nimodipine, or by 3 μM SO-3 and 0.5 μM Aga. Also, 3 μM SO-3 had no effect on R-type currents.SO-3 had less inhibitory effects on non-N-type HVA currents than MVIIA at higher concentrations (30 and 100 μM).The inhibitory effects of SO-3 and MVIIA on HVA currents were almost fully reversible. However, the recovery from block by MVIIA was more rapid than recovery from block by SO-3.It is concluded that SO-3 is a new ω-conotoxin selectively targeting N-type voltage-sensitive calcium channels. Considering the significance of N-type calcium channels for pain transduction, SO-3 may have therapeutic potential as a novel analgesic agent.British Journal of Pharmacology (2005) 145, 728–739. doi:10.1038/sj.bjp.0706223; published online 9 May 2005 [ABSTRACT FROM AUTHOR]