Ebf factors and MyoD cooperate to regulate muscle relaxation via Atp2a1.

Myogenic regulatory factors such as MyoD and Myf5 lie at the core of vertebrate muscle differentiation. However, E-boxes, the cognate binding sites for these transcription factors, are not restricted to the promoters/enhancers of muscle cell-specific genes. Thus, the specificity in myogenic transcription is poorly defined. Here we describe the transcription factor Ebf3 as a new determinant of muscle cell-specific transcription. In the absence of Ebf3 the lung does not unfold at birth, resulting in respiratory failure and perinatal death. This is due to a hypercontractile diaphragm with impaired Ca(2+) efflux-related muscle functions. Expression of the Ca(2+) pump Serca1 (Atp2a1) is downregulated in the absence of Ebf3, and its transgenic expression rescues this phenotype. Ebf3 binds directly to the promoter of Atp2a1 and synergises with MyoD in the induction of Atp2a1. In skeletal muscle, the homologous family member Ebf1 is strongly expressed and together with MyoD induces Atp2a1. Thus, Ebf3 is a new regulator of terminal muscle differentiation in the diaphragm, and Ebf factors cooperate with MyoD in the induction of muscle-specific genes.

Phytochemical profiles and biological activity evaluation of Zanthoxylum bungeanum Maxim seed against asthma in murine models.

ETHNOPHARMACOLOGICAL RELEVANCE: Zanthoxylum bungeanum Maxim seed (ZBMS) has been used in Traditional Chinese Medicine (TCM) as an ingredient of polyherbal formulations for the treatment of inflammation and asthma. The aim of this study was to analyze the major composition and to evaluate the anti-asthma activity of ZBMS. MATERIALS AND METHODS: Some murine models including acetylcholine/histamine-induced asthma, ovalbumin-induced airway inflammation, ear edema and toe swelling measurement, citric acid-induced cough, and anti-stress abilities were investigated to fully study the anti-asthma activity of ZBMS.GC chromatography was also performed to analyze the major fatty acid composition of ZBMS. RESULTS: The results demonstrated that the major fatty acid composition of ZBMS includes oleic acid (20.15%), linoleic acid (26.54%), and α-linolenic acid (30.57%), which was the leading component of ZBMS, and that the total fatty acid content of ZBMS was 77.27%. The murine models demonstrated that ZBMS displays a protective effect on guinea pig sensitization, a dose-dependent inhibition of the increases in RL and decreases in Cdyn, which resulted in the relief of auricle edema and toe swelling in mice and anti-stress activity. CONCLUSION: Our results validate the traditional use of ZBMS for the treatment of asthma and other inflammatory joint disorders, and suggest that ZBMS has potential as a new therapeutic agent for asthma management.

Cis- and trans-regulatory elements of 3alpha-hydroxysteroid dehydrogenase/carbonyl reductase as biosensor system for steroid determination in the environment.

3Alpha-hydroxysteroid dehydrogenase/carbonyl reductase from Comamonas testosteroni is a key enzyme in the degradation of steroids in the environment. The encoding gene, hsdA, is expressed only at very low levels in the absence of steroids, but undergoes a several fold induction in the presence of steroid substrates. In previous investigations, we have elucidated the mechanism of hsdA regulation that involves several activators and repressors. In the present study, the hsdA gene was replaced by the green fluorescent protein (GFP) gene which was inserted downstream from the hsdA regulatory region. By homologous integration into the chromosomal DNA, the C. testosteroni mutant strain CT-GFP5-1 was generated and used as fluorescence based biosensor system for steroid determination.With this cell-based system we could determine testosterone in a range between 57 and 450 pg/ml, estradiol between 1.6 and 12.8 pg/mland cholesterol between 19.3 and 15.4 pg/ml.. With the resulting cell-free system we could determine testosterone in a range between 28 and 219 pg/ml, estradiol between 0.029 and 0.430 pg/mg and cholesterol between 9.7 and 77.2 pg/ml [DOSAGE ERROR CORRECTED].The recovery ratio of the extraction was around 95% and the maximum fluorescence signals were obtained as early as after 30 min. Limitations of the established steroid biosensor system were quenching at higher steroid concentrations and the relatively high background of fluorescence, which are currently being improved in our lab. Combined, by exploiting the regulatory region of the gene hsdA that codes for the enzyme 3 alpha-hydroxysteroid dehydrogenase/carbonyl reductase we have constructed a mutant C. testosteroni strain that can be used as a sensitive biosensor system for steroid determination in the environment.

[Inhibition of Cryptoporus volvatus ferment substance on release of leukotriene B4, C4 and D4 from neutrophils in rats in vitro].

OBJECTIVE: To study inhibitory the effects of Cryptoporus volvatus ferment substance(CVFS) on leukotriene production in vitro from neutrophils in rats. METHODS: Neutrophil aggregation was induced by intraperitoneal injection of glycogen in rats. After 16 h, intraperitoneal lavage fluid(PLF) was collected and neutrophils were removed. Neutrophils were stimulated by calcium ionophore A23187 in vitro to produce leukotriene B(4), C(4), D(4). The concentrations of leukotriene B(4), C(4) and D(4) were measured by reversed-phase high-performance liquid chromatography(HPLC). RESULT: CVFS at 0.25, 1, 4 mg x L(-1)decreased leukotriene B(4), C(4), D(4) release from neutrophils in a concentration-dependent manner. Inhibitory rate of CVFS 0.25, 1, 4 mg x L(-1 )on A23187-induced leukotriene B(4) production was 27.4%, 54.2% and 78.8%(P<0.05), respectively. Inhibitory rate of leukotriene C(4) production was 65.1%, 74.3 and 79.0%(P<0.05), respectively. Inhibitory rate of leukotriene D(4) production was 55.6%, 60.9% and 72.8%(P<0.05), respectively. CONCLUSION: The results suggest that suppression of leukotriene release may be a mechanism of the anti-inflammation and anti-asthma effects of CVFS.

[Effect of Cryptoporus volvatus (Peck) Schear on leukotriene production from polymorphonuclear leukocytes in rats].

OBJECTIVE: To study action of Cryptoporus volvatus ferment substance (CVFS) on leukotriene production of polymorphonuclear leukocytes in rats. METHODS: The level of slow reaction substance (SRS) and leukotriene B4 (LTB4) in polymorphonuclear leukocytes (PMNs) in rats in vitro were determined with bioassay and HPLC. RESULTS: CVFS 0.9, 2.7 g.kg-1 by ig significantly inhibited SRS and LTB4 production in PMNs in rats in vivo. CONCLUSION: The inhibition effect of CVFS on SRS and LTB4 release may be related to its mechanism of anti-inflammation and anti-asthma.