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21.
Background
Eosinophilia plays the major role in the pathogenesis of asthma and correlates with the up‐regulation of eotaxin, which, together with interleukin (IL)‐5, is important for differentiation, chemo‐attraction, degranulation, and survival of eosinophils in local tissue. In a previous study, we found that administration of lentivirus‐delivered short hairpin RNA (shRNA) to suppress the expression of IL‐5 inhibited airway inflammation. The present study aimed to investigate the role of eotaxin shRNA and the synergistic effect of eotaxin and IL‐5 shRNAs on airway inflammation in an ovalbumin (OVA)‐induced murine model of asthma.Methods
Lentivirus‐delivered shRNAs were used to suppress the expression of eotaxin and/or IL‐5 in local tissue in an OVA‐induced murine asthma model.Results
Intra‐tracheal administration of lentivirus containing eotaxin shRNA expressing cassette (eoSEC3.3) efficiently moderated the characteristics of asthma, including airway hyper‐responsiveness, cellular infiltration of lung tissues, and eotaxin and IL‐5 levels in bronchio‐alveolar lavage fluid. Administration of lentiviruses expressing IL‐5 or eotaxin shRNAs (IL5SEC4 + eoSEC3.3) also moderated the symptoms of asthma in a mouse model.Conclusions
Local delivery of lentiviruses expressing IL‐5 and eotaxin shRNAs provides a potential tool in moderating airway inflammation and also has the potential for developing clinical therapy based on the application of shRNAs of chemokines and cytokines involved in T helper 2 cell inflammation and eosinophilia. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献22.
zge Karayel Francesca Tonelli Sebastian Virreira Winter Phillip E. Geyer Ying Fan Esther M. Sammler Dario R. Alessi Martin Steger Matthias Mann 《Molecular & cellular proteomics : MCP》2020,19(9):1546-1560
Highlights
- •MS-based clinical assay that accurately determines phospho Rab10 occupancy.
- •Stable isotope labeled phosphopeptide injected as a standard with endogenous tryptic phospho Rab peptide for accurate ratio determination.
- •Determination of pRab levels in neutrophils of Parkinson disease patients.
- •Relevance of pRab levels as marker of PD.
23.
Although acupuncture therapy is widely used in traditional Asian medicine for the treatment of diverse internal organ disorders, its underlying biological mechanisms are largely unknown. Here, we investigated the functional involvement of acupuncture stimulation (AS) in the regulation of inflammatory responses. TNF-α production in mouse serum, which was induced by lipopolysaccharide (LPS) administration, was decreased by manual acupuncture (MAC) at the zusanli acupoint (stomach36, ST36). In the spleen, TNF-α mRNA and protein levels were also downregulated by MAC and were recovered by using a splenic neurectomy and a vagotomy. c-Fos, which was induced in the nucleus tractus solitarius (NTS) and dorsal motor nucleus of the vagus nerve (DMV) by LPS and electroacupuncture (EAC), was further increased by focal administration of the AMPA receptor blocker CNQX and the purinergic receptor antagonist PPADS. TNF-α levels in the spleen were decreased by CNQX and PPADS treatments, implying the involvement of inhibitory neuronal activity in the DVC. In unanesthetized animals, both MAC and EAC generated c-Fos induction in the DVC neurons. However, MAC, but not EAC, was effective in decreasing splenic TNF-α production. These results suggest that the therapeutic effects of acupuncture may be mediated through vagal modulation of inflammatory responses in internal organs. 相似文献
24.
After observing specimens of Calligonum pumilum Losinsk. and C. juochiangense Y. X. Liou in both the field and in herbarium collections, it was found that the morphological characters of these two species are quite different, especially with respect of the twisted direction of fruit ribs, number of bristle rows along each rib, rigidity and degree of interweaving of bristles, as well as their geographic distribution. Therefore, it is concluded that C. pumilum and C. juochiangense should be accepted as two independent species. 相似文献
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26.
Mutations affecting the catalytic activity of Bacillus cereus 5/B/6 beta-lactamase II 总被引:2,自引:0,他引:2
Random in vitro mutagenesis of a cloned Bacillus cereus 5/B/6 beta-lactamase II gene was used to select defective genes unable to confer ampicillin or cephalosporin C resistance to Escherichia coli. DNA sequencing of mutant genes identified histidine at position 28 as important to beta-lactamase II function. In addition, the isolation of six identical frameshift mutants established that the carboxyl-terminal end of beta-lactamase II is critical for enzyme function. Random mutagenesis also revealed that His88 (implicated previously as one of 4 residues acting as a zinc ligand) is crucial to enzymatic activity and that a glycine to glutamic acid substitution at position 148 produced a defective beta-lactamase. Oligonucleotide mutagenesis directed at Glu37 and Glu212 suggests that these residues are inconsequential to enzyme function but that histidine at position 28 may be involved in substrate binding or recognition. 相似文献
27.
Terence T. Yen 《Obesity (Silver Spring, Md.)》1994,2(5):472-480
In several species of obese animals, a group of phenethanolamine β-agonists stimulates lipolysis and thermogenesis, resulting in the loss of body fat and weight. Brown adipose tissue is considered to be the major target tissue for the antiobesity activity of these compounds. Independent of this antiobesity activity, some of these compounds are also antidiabetic and increase muscle mass. Based on the pharmacological profile of these com-pounds, a npeceptor was proposed and character-ized in mouse, rat, and humans. The 133-receptor in brown adipose tissue has been suggested to mediate the antiobesity activity of these 13-agonists. Whether this receptor is responsible for the antidiabetic activ-ity and whether there is a linkage between the antiobesity/antidiabetic activity and the nutrient par-titioning activity is not clear. Clinical trials with these mixed 13-agonists showed marginal antiobesity effects when caloric intake of subjects was restricted. Insulin sensitivity was also improved in some of the trials designed to test the antidiabetic activity of these compounds. Side effects included tachycardia and tremor. To eliminate these side effects, a second generation of compounds was selected for its agonist activity on rat D3-receptors. Clinical trials with these compounds have shown lit-tle increase of energy expenditure even at high doses. Successful development of an antiohesity and antidi-abetic drug from this class of compounds will require the elucidation of the physiological role of the human 133-receptor and the regulatory mecha-nism between fuel efficiency and feeding behavior. 相似文献
28.
急性脑梗死约占全部脑卒中的70%,病死率和致残率高,且极易复发。但目前针对急性脑梗死在时间窗内溶栓、抗凝等治疗手段不能从根本上切实有效地修复受损脑组织,且伴有出血等风险。寻找脑梗死形成发展的原因并予以治疗迫在眉睫。酸中毒是引起缺血性脑损伤的重要机制。大量实验研究表明,酸中毒能加重神经元的缺血性损伤,且其梗死面积与酸中毒的程度直接相关。但缺血产生的酸中毒如何引起神经元损伤的确切机制尚不明确。最近研究发现酸中毒能激活一种在中枢及周围神经中广泛存在的膜通道,即酸敏感离子通道,它对Ca2+通透,能引起细胞内Ca2+超载,同时能激活胞内酶引起细胞内蛋白质、脂类及核酸的降解,加重缺血后脑损伤。本文就酸敏感离子通道1a与脑梗死做一综述。 相似文献
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