The role and mechanism of 1,25-dihydroxyvitamin D3 in regulating the Rho-kinase signaling pathway in asthmatic rats.

BACKGROUND: Bronchial asthma (referred to as asthma in the present study) is the most common chronic airway inflammatory disease in childhood. The present study aimed to investigate the effect of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] on VDR expression, which is closely associated with asthmatic airway smooth muscle cells (ASMCs), and explored its role and mechanism in the Rho-kinase signaling pathway. METHODS: The acute asthma model was induced by ovalbumin (OVA) and pertussis bacillus, and ASMCs obtained from asthmatic rats were cultured in vitro. These cells were randomly divided into five groups: control (N) group, TNF-α (TNF) group, 1,25-(OH)2D3 (VD) group, dexamethasone (DXM) group, and 1,25-(OH)2D3 + DXM (L) group. The protein expression levels of VDR, ROCK, MLC20 and P-MLC20 were detected by western blot, and the mRNA expression levels of VDR, ROCK, MLC20 and P-MLC20 were detected by real-time quantitative PCR. RESULTS: The expression of ROCK, MLC20 and P-MLC20 in each treatment group were significantly lower, when compared to the TNF group (P<0.05), but this remained stronger than (P<0.05) or similar to (P>0.05) that in the N group. CONCLUSIONS: The regulation mechanism of 1,25-(OH)2D3 in alleviating asthma should be correlated to its regulation of the expression of related signaling molecules in the Rho-kinase signaling pathway, and this effect may be achieved by regulating the mRNA and protein expression of the VDR gene.

Divergent synthesis of dual 1,4-dihydropyridines with different substituted patterns from enaminones and aldehydes through domino reactions.

A concise and efficient protocol for the regioselective synthesis of dual 1,4-dihydropyridines with several substituted patterns has been developed from a cascade cyclization of enaminones and aldehydes in different media (EtOH/CH3CN). The one-pot cascade reaction involves at least five reactive sites and generates multiple C-C and C-N bonds. The established protocol explores the chemistry of enaminones by employing their three reactive sites. The method has several advantages including mild conditions, operational simplicity, and high bond-forming efficiency. It may offer promise in a variety of biochemical applications.

Nerve growth factor exacerbates allergic lung inflammation and airway remodeling in a rat model of chronic asthma.

Nerve growth factor (NGF) is critical in the pathogenesis of allergic airway inflammation in vivo and induces proliferation of airway smooth muscle cells and matrix metalloproteinase-9 (MMP-9) expression in vitro. However, the effects of NGF on chronic pulmonary diseases of allergic origin remain unknown. To investigate the effects of NGF on lung inflammation and airway remodeling, 32 Wistar rats were randomly divided into four groups: control, NGF, ovalbumin (OVA) and anti-rat-ß-NGF antibody (anti-NGF). Aerosolized OVA was administered to the rats in the NGF, OVA and anti-NGF groups to generate the asthmatic rat model, and NGF or anti-NGF was administered 3 h prior to OVA inhalation every two days. On day 70, bronchial responsiveness tests, bronchoalveolar lavage (BAL) and cell counting were conducted. The levels of serum OVA-specific immunoglobulin E (IgE) and of T-helper cell type-2 (Th2) cytokines [interleukin (IL)-4 and IL-13] in the BAL fluid were measured by enzyme-linked immunosorbent assay. The expression levels of NGF protein and MMP-9 mRNA, and the activity of MMP-9 in the lungs were detected by western blot analysis, quantitative polymerase chain reaction and gelatin zymography analysis, respectively. Our results showed that NGF significantly increased eosinophilic airway inflammation, persistent airway hyperresponsiveness (AHR), the serum levels of OVA-specific IgE and the levels of Th2 cytokines in the BAL fluid, and also increased the expression levels and activity of MMP-9. However, anti-NGF treatment significantly inhibited eosinophilic airway inflammation, persistent AHR and airway remodeling. The results showed that NGF may have exacerbated the development of airway inflammation, AHR and airway remodeling through a Th2 pathway and by increasing the level of MMP-9 expression. Therefore, anti-NGF is potentially beneficial for preventing and treating patients with asthma.

The effect of substance P on asthmatic rat airway smooth muscle cell proliferation, migration, and cytoplasmic calcium concentration in vitro.

Airway remodeling and airway hyper-responsiveness are prominent features of asthma. Neurogenic inflammation participates in the development of asthma. Neurokinin substance P acts by binding to neurokinin-1 receptor (NK-1R). Airway smooth muscle cells (ASMC) are important effector cells in asthma. Increases in ASMC proliferation, migration, and cytoplasmic Ca2+ concentration are critical to airway remodeling and hyper-responsiveness. The effects of substance P on ASMC were investigated in Wistar rats challenged with a previously described asthmatic rat model. To exclude possible influences from other factors, the role of substance P was also investigated in primary cultured rat ASMC. Substance P and WIN62577-induced changes in cytoplasmic Ca2+ concentration were observed by fluorescence microscopy, and expression of Ca2+ homeostasis-regulating genes was assessed with real-time PCR. We found that cytoplasmic Ca2+ concentration increased in normal rat ASMC treated with substance P, but decreased in asthmatic rat ASMC treated with WIN62577, an antagonist of NK-1R. Real-time PCR analysis revealed increased Serca2 mRNA expression but decreased Ip3r mRNA expression after WIN62577 treatment in asthmatic rat ASMC. Flow cytometric analysis (FCM) revealed that most asthmatic rat ASMC stayed at G1 phase after combined treatment with WIN62577 and IL-13 in vitro. Transwell analysis suggested that ASMC migration was reduced after WIN62577 treatment. Therefore, we conclude that NK-1R is related to asthma mechanisms and a NK-1R antagonist downregulates calcium concentration in asthmatic ASMC by increasing Serca2 mRNA and decreasing Ip3r mRNA expression. The NK-1R antagonist WIN62577 inhibited ASMC IL-13-induced proliferation and ASMC migration in vitro and therefore may be a new therapeutic option in asthma.

[Diagnostic study on children's diaphragmatic fatigue].

OBJECTIVE: In the recent twenty years, the diaphragmatic contraction, relaxation functions and electric activity have been explored through electromyography (EMG) and transdiaphragmatic pressure (Pdi) determination. But these techniques required some complex and expensive instruments, so the diagnosis and treatment of children's diaphragmatic fatigue have not been well evaluated. The present study explored the diagnosis of children's diaphragmatic fatigue through measuring ribcage-abdomen motion and analyzed its asynchrony. METHODS: Fifty-three children (male 37, female 16, and age rage from 1 months to 9 years) with respiratory rate > 30 breaths/min, heart rate > 110 beats/min, and respiratory dysfunction had asynchronized ribcage-abdomen motion showed by impedance respirograph (IRG). The authors observed whether ribcage-abdomen motion was synchronic and calculated M levels (staggered peak time/total duration of the breathing cycle). The ribcage and abdomen outputs were displayed on vertical (for rib cage) and horizontal (for abdomen) axes of X-Y instrument. In addition, the change of respiratory frequency and heart rate was observed and arterial blood-gas analysis was also performed. RESULTS: (1) M levels in one-dimensional IRG were positively correlated with alpha angle in two-dimensional IRG (r = 0.956, P < 0.001). Asynchronized respiratory motions could be divided into three types. type I showed completely contra-directional movements of respiration, M levels for (48.1 +/- 4.4)%, an irregularly clockwise loop in the two dimensional IRG, and alpha angle for (138.3 +/- 15.0) degrees. In type II, one dimensional IRG showed displaced peak of the chest and abdomen motion curves, M levels were (16.5 +/- 4.7)%, two dimensional IRG was displaced in a counterclockwise direction, and alpha angle was (55.3 +/- 10.8) degrees. In type III, abdominal motion curve of one dimensional IRG had double peaks, M levels were 0, two dimensional IRG was presented as 8-shaped double circles, alpha angle was (41.3 +/- 3.8) degrees; (2) pH levels in the patients with type I and type II diaphragmatic fatigue were significantly lower, and PCO(2) levels were significantly higher than those with type III or in the normal subjects (P < 0.001 for all), but there was no statistically significant difference between type III and the normal subjects (P > 0.05); (3) Both of respiratory rate and heart rate in type I, type II and type III were higher than those in the normal subjects (all P < 0.001), and the differences among the three types were significant (P < 0.001 for all); (4) Both M levels and alpha angle were negatively correlated with pH levels (r = -0.514, P < 0.001 and r = -0.497, P < 0.001), while positively correlated with PCO(2) levels (r = 0.672, P < 0.001 and r = 0.625, P = 0.01). CONCLUSIONS: (1) IRG can be reliably used to diagnose children's diaphragmatic fatigue. This technique is simple and easy to perform and non-invasive. It is therefore worthy of recommending for further clinical investigations. (2) According to the characteristics of IRG, diaphragmatic fatigue can be divided into three types. (3) The development of children's diaphragmatic fatigue has a series of characteristic changes. (4) To avoid the patients suffering from respiratory failure, it is the key time to adopt the policies of prevention and treatment when IRG shows signs of type III diaphragmatic fatigue.

[Design and clinical application of a three-dimensional biomechanical traction appliance for protrusion of intervertebral disc].

A three-dimensional biomechanical tracting appliance is introduced in the article, which is used to treat the protrusion of intervertebral disc. The appliance is light, practical, adjustable 3D biomechanic, simple and with multiple functions and convenient operation.

[Effect of shenmai injection on diaphragmatic fatigue in children with respiratory failure].

OBJECTIVE: To study the effect of Shenmai injection (SMI) on diaphragmatic fatigue in children with respiratory failure. METHODS: Thirty-five cases of children respiratory failure with diaphragmatic fatigue were divided into two groups. The control group was treated with comprehensive therapy including anti-infection, oxygen inhalation and parenteral nutrition, etc. The SMI group was treated with SMI intravenously, besides the comprehensive therapy as in the control group. Taking electrical impedance respirogram (IRG) as criterion of therapeutic effect, the effective cases after 30 min medication, time for diaphragmatic fatigue disappearance, as well as arterial blood gas analysis before and after treatment were analyzed. RESULTS: (1) In 30 min after medication, the effective cases in the SMI group (15/18) were more than that in the control group (4/17, P < 0.01); (2) Blood pH increased and PaCO2 decreased in both groups after treatment, but the decrease of PaCO2 was more significant in the SMI group (P < 0.05); (3) Time of diaphragmatic fatigue disappearance in the SMI group was shorter than that in the control group (P < 0.01). CONCLUSION: SMI is an effective drug for treatment of diaphragmatic fatigue in children with less adverse effect, and worthwhile for spreading in clinical practice.