PLCε1 mediates one-lung ventilation injury by regulating the p38/RhoA/NFκB activation loop.

BACKGROUND: Phospholipase C epsilon-1 (PLCε1) might be a novel and potential target in treating inflammatory conditions. In the present study, we aimed to clarify whether PLCε1 is involved in lung injury caused by one-lung ventilation (OLV) and to elucidate the potential molecular mechanism of PLCε1-mediated signaling pathway on OLV induced inflammatory response and injury. METHODS: Male Sprague-Dawley (SD) rats were divided into wide-type (PLCε1-WT) group and PLCε1-KO group, and were treated with OLV for 0.5 h, 1 h, and 2 h respectively. Observation of lung tissue injury in rats was performed by Hematoxylin and eosin (HE) staining and Wet/dry (W/D) radios. In addition, pulmonary microvascular endothelial cells (PMVECs) transfected with PLCε1-si RNA, were stimulated by lipopolysaccharide (LPS). To explore the possible roles of PLCε1 in the OLV induced inflammatory injury and the involved pathway underlying, the lung tissue and bronchoalveolar lavage fluids (BALF) of OLV rats, as well as the PMVECs were prepared for further analysis. Enzyme-linked immunoassay (ELISA) was used to detect the expression of pro-inflammatory factors. The activities of related pathway proteins (NF-κB, phospho-p38, p38, phospho-ERK1/2, ERK1/2, RhoA and ROCK) were also detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. RESULTS: Compared to the PLCε1-WT rats, PLCε1-KOrats exhibited marked alleviation of lung inflammation as shown by great reduction in lung wet/dry weight ratios, decreases in the expressions of pro-inflammatory mediators, and declines in the number of neutrophils and the protein concentration in bronchoalveolar lavage fluid (BALF). Moreover, the increased expressions of RhoA and NF-κB p65 mRNA induced by OLV were significantly inhibited in PLCε1-KO rats. In LPS treated PMVECs, PLCε1-si RNA transfection ones also showed the decrease expression of proinflammatory mediators, reduction in p38 phosphorylation levels and downregulation of RhoA/ROCK signaling activation. Co-cultured with PLCε1-si RNA and BTRB796 (p38 inhibitors) in LPS-stimulated PMVECs resulted in a significant reduction in RhoA and NF-κB activity. In addition, treatment with either ROCK inhibitor (Y-27632) or dominant negative mutant of RhoA (RhoT19 N) significantly reduced the expression of NF-κB in PLCε1-si RNA treated PMVECs. CONCLUSION: The results indicated that PLCε1 played an important role in the inflammatory response induced by OLV. Moreover, through promoting p38/RhoA/ROCK activation loop, PLCε1 promoted NF-κB activation and thereby increased the expressions of inflammatory mediators, which induced the PMVECs inflammation and subsequent injury. The results of this study provide a potential therapeutic target for the reduction of inflammatory response in patients with OLV.

[Application of random forest algorithm in fingerprint of Chinese medicine: different brands of Xiasangju granules as example].

To establish a random forest algorithm for identifying and classifying different brands of Xiasangju granules, and provide effective reference for identifying multi-index complex fingerprint. HPLC method was used to collect the fingerprint of 83 batches of Xiasangju granules from different manufacturers. The classification of Xiasangju granules samples based on chromatographic fingerprints was identified by chemometric methods including principal component analysis (PCA), partial least squares discriminate analysis (PLS-DA) and random forest analysis (RF). The superiority of the above three chemometric methods was compared. The results showed that the fingerprints of 83 batches of Xiasangju granules were established in this study. PCA could only explicate 56.52% variance contribution rate and could not completely classify the samples; PLS-DA analysis was superior to PCA, explicating 63.43% variance contribution rate and could obtain certain separation; RF could well classify the samples into 3 types, and the predication accuracy of the proposed method was 96.5%. Therefore, The results indicate that RF combined with HPLC fingerprint could effectively construct traditional Chinese medicine quality control and analysis system.

[Preparation of liposomal artesunate dry powder inhalers and the effect on the acute lung injury of rats].

Artesunate is one of artemisinin derivatives with anti-malarial and anti-inflammatory activities though its water solubility and bioavailability are low. Acute lung injury (ALI) is a seriously dispersive lung disease with a high mortality. In this study, artesunate liposomes were prepared with the film dispersion method, and then lyophilized to obtain the liposomal artesunate dry powder inhalers(LADPIs). The LADPIs were pulmonary-delivered into the lung to treat ALI in rats. The artesunate liposomes had the capsulation efficiency of 71.4%, the particle size of 47.3 nm, and the zeta potential of -13.7 m V. The LADPIs had the aerodynamic particle size of 4.2 µm and the fine particle fraction (FPF) of 34.5%. ALI was established in rats by instilling lipopolysaccharide (LPS) into the lungs. The rats quickly showed a reduction in movement and acceleration in breath followed by diarrhea and so on. The LADPIs were directly administrated into the lungs of ALI rats through airways after 1 h of LPS challenge. The treatment induced a reduction in ALI syndromes. Two inflammatory factors, including TNF-α and IL-6, were significantly reduced by the artesunate powder in the LADPI group similarly to the reduction in the positive drug dexamethasone group (P < 0.05). Therefore, the anti-inflammatory effect of LADPIs contributed to the anti-ALI activity. Furthermore, the liposomal formulation improved drug bioavailability in the lung and increased therapeutic efficiency. The LADPIs are promising medicines for therapy of ALI through local drug administration.

Modulation of intracellular calcium transient in response to beta-adrenoceptor stimulation in the hearts of 4-wk-old rats during simulated weightlessness.

Modulation of intracellular calcium ([Ca(2+)](i)) transient in response to beta-adrenoceptor stimulation in the hearts of hindlimb unweighted (HLU) rats during simulated weightlessness has not been reported. In the present study, we adopted the rat tail suspension for 4 wk to simulate weightlessness. Effects of simulated microgravity on beta-adrenoceptor responsiveness were then studied. Mean arterial blood pressure, left ventricular pressure (LVP), systolic function [maximum positive change in pressure over time (+dP/dt(max))], and diastolic function [maximum negative change in pressure over time (-dP/dt(max))] were monitored during the in vivo experiment. beta-Adrenoceptor density was quantitated by radioactive ligand binding. Single rat ventricular myocyte was obtained by enzymatic dissociation method. +/-dP/dt(max), myocyte contraction, intracellular [Ca(2+)](i) transient, and L-type calcium current in response to beta-adrenoceptor stimulation with isoproterenol were measured. Compared with the control group, no significant changes were found in heart weight, body weight, and mean arterial blood pressure, whereas LVP and +/-dP/dt(max) were significantly reduced. LVP and +/-dP/dt(max) were significantly attenuated in the HLU group in response to isoproterenol administration. In the in vitro study, the beta-adrenoceptor density was unchanged. Effects of isoproterenol on electrically induced single-cell contraction and [Ca(2+)](i) transient in myocytes of ventricles in HLU rats were significantly attenuated. The enhanced L-type Ca(2+) current elicited by isoproterenol in cardiomyocytes was significantly decreased in the HLU group. The above results indicate that impaired function of L-type Ca(2+) current and decreased [Ca(2+)](i) transient cause the depressed responsiveness of the beta-adrenoceptor stimulation, which may be partially responsible for the depression of cardiac function.

Distribution of kappa-opioid receptor in the pulmonary artery and its changes during hypoxia.

The present study evaluated the distribution of kappa-opioid receptors (kappa-ORs) in pulmonary arteries (PAs) in rats and investigated whether kappa-ORs are altered in PAs during hypoxia. An animal model of hypobaric/hypoxic pulmonary hypertension and a pulmonary artery smooth muscle cell (PASMC) model of hypoxia were utilized. Distribution of kappa-ORs was determined by fluorescence immunohistochemistry and changes in kappa-ORs expression in PAs and PASMCs were determined by fluorescence immunohistochemistry or Western blot techniques. The kappa-ORs were primarily distributed in the smooth muscle layer of the PAs and in the nucleus of PASMCs. The expression of the kappa-ORs were increased in PAs of rats subjected to hypoxia for 1-4 week (P < 0.01). Accordingly, the expression of kappa-ORs in PASMCs were also increased when subjected to hypoxia for 12-36 hr (P < 0.05). The present study has provided evidence for the first time of the precise location of kappa-ORs in PAs and PASMCs of rats and that hypoxia upregulates expression of kappa-ORs.

Stimulation of kappa-opioid receptor reduces isoprenaline-induced cardiac hypertrophy and fibrosis.

The aim of the present study was to determine whether U50,488H (a selective kappa-opioid receptor agonist) inhibits cardiac hypertrophy and fibrosis induced by beta-adrenoceptor stimulation in a rat model. Cardiac hypertrophy and fibrosis were developed by intraperitoneal administration of isoprenaline (ip. 3.0 mg/kg/day,14 days). In the isoprenaline-treated group, heart weight and heart-to-body ratio increased significantly. Hypertrophic alterations were observed in light micrographs of tissue and transmission electron micrographs of myocardial ultra structures. Increases in heart weight, heart-to-body ratio, diameter of cardiomyocytes, and morphological hypertrophic alterations induced by isoprenaline were significantly attenuated by U50,488H(i.p. 1.25 mg/kg/day). Growth of cardiomyocytes was induced by incubating with isoprenaline (10(-6) mol/l), which resulted in an increase in optical density (OD) values. The increased OD value was attenuated by U50,488H(10(-7) mol/l-10(-5) mol/l) in a dose dependent manner. Animals receiving administration of isoprenaline displayed significant fibrosis. The extent of isoprenaline induced left ventricular fibrosis was dramatically reduced in U50,488H treated animals. Increased cardiac fibroblast proliferation and collagen synthesis induced by isoprenaline, as evidenced by increased OD value, (3)H-thymidine, and (3)H-proline incorporation, were significantly reduced in the U50,488H treated group. The specific extracellular matrix proteins, including type I, type III collagen and fibronectin, which increased after administration of isoproterenol, were also attenuated by U50,488H. The abovementioned effects of U50,488H were completely abolished by nor-BNI (nor-binaltorphimine), a selective kappa-opioid receptor antagonist. The enhanced intracellular Ca(2+) transient and L-type Ca(2+) current elicited by isoprenaline in cardiomyocytes were significantly inhibited by U50,488H. This study provides the first morphological evidence of the inhibitory effect of U50,488H on isoprenaline-induced cardiac hypertrophy and fibrosis via kappa-opioid receptor stimulation.

Inhibition of hypoxia-induced proliferation and collagen synthesis by vasonatrin peptide in cultured rat pulmonary artery smooth muscle cells.

The aim of the present research is to investigate the effects of vasonatrin peptide (VNP) on hypoxia-induced proliferation and collagen synthesis in pulmonary artery smooth muscle cells (PASMCs). Smooth muscle cells isolated from rat pulmonary artery were cultured and used at passages 3-5. Cell proliferation and collagen synthesis were evaluated by cell counts, [(3)H] thymidine and [(3)H] proline incorporation. The results showed that cells exposed to hypoxia for 24 h exhibited a significant increase in [(3)H] thymidine (93%) and [(3)H] proline (52%) incorporation followed by a significant increase in cell number (47%) at 48 h in comparison with the respective normoxic controls. VNP reduced hypoxia-stimulated increase in cell proliferation in a concentration-dependent manner from 10(-8) to 10(-6) mol/L and attenuated hypoxia-induced collagen synthesis ranging from 10(-6) to 10(-5) mol/L, which is similar to but more potent than both ANP and CNP. The action of VNP on PASMCs was mimicked by 8-bromo-cGMP (10(-4) mol/L, the membrane-permeable cGMP analog), and blocked by HS-142-1 (2 x 10(-5) mol/L), the particulate guanylyl cyclase-coupled natriuretic peptide receptor antagonist, or KT-5823 (10(-6) mol/L), the cGMP-dependent protein kinase (PKG) inhibitor. The results suggest that VNP inhibits hypoxia-stimulated proliferation and collagen synthesis in cultured rat PASMCs via particulate guanylyl cyclase-coupled receptors through cGMP/PKG dependent mechanisms.

Estrogen affects the differentiation and function of splenic monocyte-derived dendritic cells from normal rats.

AIM: To explore the mechanism resulting in the preventive effect of estrogen on experimental autoimmune encephalomyelitis (EAE), which is an animal model for multiple sclerosis (MS), and examine if estrogen can affect the immune response in EAE at dendritic cell (DC) level. METHODS: Flow cytometry was used to reveal the surface marker expression. 3H-thymidine incorporation was applied to examine the cellular proliferation. Levels of anti-myelin basic protein (MBP)(68-86) antibody and cytokines were determined by enzyme-linked immunospot and ELISA, respectively. RESULTS: 17beta-estradiol (E2) could dose-dependently accelerate the differentiation process of DCs by up-regulating CD11c, B7-2 and CD40 expressions, but exert no effect on its antigen presentation ability. MBP-specific T cells cocultured with E2-treated DCs (E2-DC) produced more IL-10 and less IFN-gamma in the supernatant than those without E2 pretreatment (ctr-DC). In contrast to ctr-DC, E2-DC, if injected i.v. into EAE rats on day 5 post immunization, could initiate antigen nonspecific hyper-responsivity in T cells in terms of enhanced proliferation and cytokine secretion of mononuclear cells in LN, but suppressed antibody secretion from splenocytes. CONCLUSION: These results suggest that estrogen can affect the differentiation and function of DCs, which leads T cells switching to Th2 secretion. This may account partly for the protective effect of estrogen on EAE.

Morphological observation of immunological alterations in the spleens from estrogen receptor deficient mice.

AIM: To evaluate some immunological parameters in the spleens from estrogen receptor(ER) deficient mice. METHODS: Immunohistochemistry and immunofluorescence analysis were used in the study. RESULTS: Multiple alterations were found in the spleens of ER deficient mice, especially in ERbeta deficient mice, such as increased expression of proinflammatory cytokines and inducible nitric oxide synthase, elevated number of proliferating splenocytes and increased IgM/IgG production. Moreover, The splenocytes lack of ERbeta were resistant towards estrogen's suppression on proliferation. The activation of nuclear factor (NF)-kappaB in ERbeta deficient spleens may account for the above hyperactivity. CONCLUSION: ER, especially ERbeta, plays a key role in mediating the modulation of immune response by estrogen. ERbeta disruption may increase the sensibility towards autoimmune diseases.

Predominant Th2-type response during normal pregnancy of rats.

The immunological parameters were analyzed during pregnancy of Lewis rats by the methods of flow cytometry, thymidine incorporation and enzyme-linked immunospot (ELISPOT). MHC II of spleen mononuclear cells (MNCs) and CD11c of periphery blood MNCs was apparently downregulated in late pregnancy, while the costimulatory molecules B7-1 and B7-2 showed no difference. Increased expression of Th2 cytokines (IL-10, IL-4) and TGFbeta was detected in the spleen and peripheral blood MNCs in the third trimester by flow cytometry. No suppression of Th1 cytokine represented by IFNgamma was found. Furthermore, antigen specific proliferation of spleen and peripheral blood MNCs was unchanged, but higher proliferation of MNCs from mesenteric lymph nodes was shown in late pregnancy. There was an inhibition of antigen specific antibody production in pregnancy examined by ELISPOT. These data indicate the immunomodulatory effects of sex-hormones in pregnancy, which may be related to the remission of T cell-mediated autoimmune diseases during pregnancy.

Down-regulation of C-type natriuretic peptide receptor by vasonatrin peptide in cardiac myocytes and fibroblasts.

AIM: To investigate the regulatory effects of vasonatrin peptide (VNP) on the expression of C-type natriuretic peptide receptor (NPR-C) in cultured neonatal rat cardiac myocytes and fibroblasts. METHODS: Quantitative RT-PCR was undertaken to evaluate the levels of NPR-C mRNA and radioimmunoassay was used to determine the formation of intracellular cGMP. RESULTS: Twenty-four hours hypoxic exposure increased the level of NPR-C mRNA in cardiomyocytes, while did not alter the expression of NPR-C in cardiac fibroblasts. VNP (10(-8)-10(-6) mol/L) reduced the levels of NPR-C mRNA in cardiac myocytes induced by hypoxia in a concentration-dependent manner, and with high concentration (10(-6) mol/L) also decreased the expression of NPR-C in cardiac fibroblasts and air-control cardiac myocytes. The inhibitory effects of VNP on the expression of NPR-C was mimicked by 8-bromo-cGMP 10(-6) mol/L (a membrane permeable analog of cGMP). VNP (10(-8)-10(-6) mol/L) increased the formation of intracellular guanosine-3',5'-cyclic monophosphate (cGMP) in both cardiac myocytes and fibroblasts. HS-142-1, the particulate guanylyl cyclase-coupled receptor antagonist, partially abrogated the above effects of VNP. CONCLUSION: Hypoxic exposure for 24 h up-regulated the expression of NPR-C in cultured neonatal rat cardiac myocytes. VNP decreased the expression of NPR-C in cardiac myocytes and fibroblasts under both air-control and hypoxic condition, which was at least partially mediated by guanylate cyclase linked natriuretic peptide receptors through increasing the intracellular cGMP.

Disruption of estrogen receptor beta in mice brain results in pathological alterations resembling Alzheimer disease.

AIM: To study the pathological characteristics of the mice with estrogen receptor beta (ER beta) disruption in brain. METHODS: Immunohistochemistry method was applied in the study. RESULTS: beta-Amyloid peptide(A beta (42)) and apolipoprotein E (ApoE) immunoreactive substances were accumulated notably in cortex and limbic structures such as the hippocampus and amygdala in brain, resembling the pathological changes of human Alzheimer disease(AD). A beta formed cloudy-like deposits in parenchyma of brain, while apoE also deposited along or surrounding the blood vessels. CONCLUSIONS: ER beta is crucial to the development of neural degenerative disease, so modulation of A beta metabolism via ER beta signal pathway might be beneficial for AD prevention or therapy.

Estrogen influences the differentiation, maturation and function of dendritic cells in rats with experimental autoimmune encephalomyelitis.

AIM: To examine if estrogen can affect the immune response at the dendritic cells (DCs) level in rats with experimental autoimmune encephalomyelitis (EAE). METHODS: Lewis rats were immunized with inoculum containing MBP(68-86). DCs were derived from spleen monocytes of EAE rats with IL-4 and GM-CSF in presence of 17 beta-estradiol (E2). Nitric oxide (NO) was detected by Griess reagent. The surface markers and cytokines production of DCs were shown by flow cytometry. DCs were cocultured with MBP-specific T cells, [(3)H]-TdR incoportation was used to reveal the antigen presentability, the supernatant of the coculture were collected to examine the cytokines secretion by ELISA. RESULTS: E2 activated DCs by accelerating the maturation process characterized by upregulation of MHC II and costimulating molecule B7-1, B7-2, drastic high expression of CD40. IFN-kappa-producing DCs were also elevated without any alteration of IL-10. Estradiol-treated DCs (E2-DCs) secreted more NO in the culture supernatant. By contrast, E2-DCs showed decreased antigen presentation ability with reduced secretion of IFN-kappa but no alteration of IL-10 in the coculture with T cells. CONCLUSION: Estrogen can affect the differentiation, maturation and function of DCs from EAE rats, which may be attributed to its protection against EAE and the remission of multiple sclerosis patients in pregnancy.

[Effects of niflumic acid on the proliferation of human hepatoma cells].

The purpose of this work was to investigate the effects of niflumic acid (NFA), a chloride channel blocker, on the proliferation of human hepatoma cell line (HHCC). Cell proliferation was analyzed by cell count and MTT assay. Cell cycle analysis was carried out by flow cytometry. [Ca(2+)](i) was determined by laser scanning confocal system. It was found that NFA decreased significantly the cell number and the MTT optical density (OD) of HHCC cells, and that the OD value was reversed after washout of NFA. Compared with control, NFA blocked cell cycle progression in G(1) phase. Extracellular application of NFA (100 micromol/L) induced a rapid decrease in [Ca(2+)](i). These findings demonstrate that blockage of chloride channels by NFA induces growth arrest of HHCC in G(1) phase, which may be due to the inhibition of Ca(2+)/CaM-dependent signaling pathways.

[Pharmacokinetics of genistein in beagle dogs].

AIM: To study the pharmacokinetics of genistein in Beagle dogs. METHODS: Genistein, suspended in 0.5% CMC-Na solution, was orally administered to Beagle dogs at the dose of 5.34 mg.kg-1. At various time intervals, 1.5 mL of blood was drawn from the vein of dogs in their front legs. At the same time, urine and feces were collected. After the collection, the feces were homogenized with physiological saline (to 1 g feces, 10 mL physiological saline were added). The genistein in plasma, urine and homogenized feces was extracted twice by vortexing with 2.0 mL mixture of methyl tert-butyl ether and pentane (8:2). The organic phase was transferred into tubes and evaporated in ventilation cabinet. The residue was dissolved in 50 microL of methanol and 20 microL of the solution was drawn and detected by high-performance liquid chromatography. The pharmacokinetic parameter was calculated by 3P97 software. RESULTS: The plasma concentration-time curve was fitted to a one-open-compartment model. The peak time was 0.29 h, and the elimination half-life was 0.52 h. After genistein was administered, 10.79% of genistein were excreted from urine and 21.55% from feces within 24 h. It was also found that 13.00% genistein were excreted from urine and 52.46% from feces within 60 h. CONCLUSION: It showed that the speed of absorption and elimination of genistein was high in Beagle dog, and genistein was mainly excreted in the form of parent compound in urine and feces.