The chloride channel 7 gene(CLC 7)of the Hong Kong oyster Crassostrea hongkongensis was cloned and named ChCLC 7.The cDNA was 2572 bp in length,with a 5′non-coding region containing 25 bp,a 3′non-coding region conta...The chloride channel 7 gene(CLC 7)of the Hong Kong oyster Crassostrea hongkongensis was cloned and named ChCLC 7.The cDNA was 2572 bp in length,with a 5′non-coding region containing 25 bp,a 3′non-coding region containing 327 bp,and an open reading frame of 2298 bp.ChCLC 7 has 96.8%and 92.1%homology with CLC 7 of Crassostrea gigas and Crassostrea virginica,respectively,and it was clustered with CLC 7 of C.gigas and C.virginica.QRT-PCR showed that ChCLC 7 was expressed in all eight tissues,with the highest in adductor muscle and second in gill.The ChCLC 7 expression pattern in gill was altered significantly under high salinity stress with an overall upward and then downward trend.After RNA interference,the expression of ChCLC 7 and survival rate of oyster under high salinity stress was reduced significantly,and so did the concentration of hemolymph chloride ion in 48-96 h after RNA interference.We believed that ChCLC 7 could play an important role in osmoregulation of C.hongkongensis by regulating Cl^(-)transport.This study provided data for the analysis of molecular mechanism against oyster salinity stress.展开更多
Objective A calcium-activated chloride current (ICl(Ca)) has been observed in medium-sized sensory neurons of the dorsal root ganglion (DRG). Axotomy of the sciatic nerve induces a similar current in the majorit...Objective A calcium-activated chloride current (ICl(Ca)) has been observed in medium-sized sensory neurons of the dorsal root ganglion (DRG). Axotomy of the sciatic nerve induces a similar current in the majority of medium and large diameter neurons. Our aim is to identify the molecule(s) underlying this current. Methods Using conventional and quantitative RT-PCR, we examined the expression in DRG of members of three families of genes, which have been shown to have latch) current inducing properties. Results We showed the detection of transcripts representing several members of these families, i.e. chloride channel calciumactivated (CLCA), Bestrophin and Tweety gene families in adult DRG, in the normal state and 3 d after sciatic nerve section, a model for peripheral nerve injury. Conclusion Our analysis revealed that that mBestl and Tweety2 appear as the best candidates to play a role in the injury-induced Icl(Ca) in DRG neurons.展开更多
BACKGROUND:Chloride channels participate in non-neuronal apoptosis.However,it remains unclear whether chloride channels are involved in ischemic neuronal apoptosis.OBJECTIVE:To explore the effects of 4-acetamido-4'...BACKGROUND:Chloride channels participate in non-neuronal apoptosis.However,it remains unclear whether chloride channels are involved in ischemic neuronal apoptosis.OBJECTIVE:To explore the effects of 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid (SITS) and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS),two chloride channel blockers,on the hippocampal neuronal apoptosis induced by 3-morpholinosydnonimine (SIN-1) based on the nitric oxide toxicity theory of neuronal apoptosis following ischemic brain injury.DESIGN,TIME AND SETTING:Comparative observation and in vitro experiments were performed at the laboratory of Zhuhai Campus of Zunyi Medical College from January to May 2009.MATERIALS:SIN-1,SITS,and DIDS were purchased from Sigma,USA.METHODS:Hippocampal neurons from Sprague-Dawley rats,aged 1 day,were cultured In vitro for 12 days and randomly assigned to control,SIN-1,or chloride channel blocker groups.SIN-1 group neurons were induced by SIN-1 for 18 hours to establish a model of ischemic neuronal apoptosis.Neurons in chloride channel blocker groups were treated with SITS or DIDS plus SIN-1 for 18 hours.The controls were cultured in DMEM/Ham's F12 complete medium alone.MAIN OUTCOME MEASURES:The apoptotic neurons and nuclear appearance were detected by Hoechst 33258 fluorescence staining; neuronal viability was quantitatively determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis.Caspase-3 activity was analyzed by Western blot.RESULTS:SIN-1 (1 mmol/L) dramatically induced apoptosis (50%-60%).SITS and DIDS inhibited nitric oxide-induced neuronal injury in a dose-dependent manner,suppressed caspase-3 activation,reduced neuronal apoptosis,and improved neuronal survival.CONCLUSION:Chloride channel blockers can protect against neuronal injury induced by NO.Chloride channels might be involved in neuronal apoptosis following cerebral ischemia.展开更多
Over-production of nitric oxide is pathogenic for neuronal apoptosis around the ischemic area fol- lowing ischemic brain injury. In this study, an apoptotic model in rat hippocampal neurons was es- tablished by 0.5 mm...Over-production of nitric oxide is pathogenic for neuronal apoptosis around the ischemic area fol- lowing ischemic brain injury. In this study, an apoptotic model in rat hippocampal neurons was es- tablished by 0.5 mmol/L 3-morpholinosyndnomine (SIN-l), a nitric oxide donor. The models were then cultured with 0.1 mmol/L of 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS; the chloride channel blocker)for 18 hours. Neuronal survival was detected using the 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and apoptosis was assayed by Hoechst 33342-labeled neuronal DNA fluorescence staining. Western blot analysis and immunochemilumi- nescence staining were applied to determine the changes of activated caspase-3 and CIC-3 channel proteins. Real-time PCR was used to detect the mRNA expression of CIC-3. The results showed that SIN-1 reduced the neuronal survival rate, induced neuronal apoptosis, and promoted CIC-3 chloride channel protein and mRNA expression in the apoptotic neurons. DIDS reversed the effect of SIN-I. Our findings indicate that the increased activities of the CIC-3 chloride channel may be involved in hippocampal neuronal apoptosis induced by nitric oxide.展开更多
Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2'-disulfonic ...Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid. Results showed that the survival rate of neurons was significantly increased after treatment with 4,4-diisothiocyanatostilbene-2,2'-disulfonic acid, and the rate of apoptosis decreased. In addition, the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor were significantly reduced. Our experimental findings indicate that the chloride channel blocker 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid can antagonize apoptotic cell death of hippocampal neurons by inhibiting the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor.展开更多
Using whole-cell patch-clamp recordings, the effects of antigliomatin were observed on chloride channels on C6 glioma cells cultured in vitro. Antigliomatin was extracted from the venom of the scorpion Buthus martensi...Using whole-cell patch-clamp recordings, the effects of antigliomatin were observed on chloride channels on C6 glioma cells cultured in vitro. Antigliomatin was extracted from the venom of the scorpion Buthus martensii Karsch. Chloride channels are closed under normal osmotic pressure. When osmotic pressure was reduced to 120, 110 and 100 mV, the cell volume enlarged, chloride channels opened, and the chloride channel current increased. Three minutes after antigliomatin treatment, the chloride channel current decreased in a dose-dependent manner. These results show that antigliomatin extracted from the venom of the scorpion Buthus martensii Karsch diminishes chloride channel currents on C6 glioma cells.展开更多
A thiazolidinone CFTR inhibitor(CFTR_ inh-172 ) was synthesized by a three-step procedure with trifluromethylaniline as the starting material. The synthesized CFTR inhibitor was characterized structurally by means of...A thiazolidinone CFTR inhibitor(CFTR_ inh-172 ) was synthesized by a three-step procedure with trifluromethylaniline as the starting material. The synthesized CFTR inhibitor was characterized structurally by means of 1H NMR and functionally in a CFTR-expressing cell line FRT/hCFTR/EYFP-H148Q by both fluorescent and electrophysiological methods. A large amount(100 g) of high-quality small molecule thiazolidinone CFTR chloride channel inhibitor,CFTR_ inh-172 ,can be produced with this simple three-step synthetic procedure. The structure of the final product 2-thioxo-3-(3-trifluromethylphenyl)-5-[4-carboxyphenyl- methylene]-4-thiazolidinone was confirmed by 1H NMR. The overall yield was 58% with a purity over 99% as analyzed by HPLC. The synthesized CFTR_ inh-172 specifically inhibited CFTR chloride channel function in a cell-based fluorescence assay( K _d≈1.5 μmol/L) and in a Ussing chamber-based short-circuit current assay( K _d≈0.2 μmol/L),indicating better quality than that of the commercial combinatorial compound. The synthesized inhibitor is nontoxic to cultured cells at a high concentration and to mouse at a high dose. The synthetic procedure developed here can be used to produce a large amount of the high-quality CFTR_ inh-172 suitable for antidiarrheal studies and for creation of cystic fibrosis models in large animals. The procedure can be used to synthesize radiolabled CFTR_ inh-172 for in vivo pharmacokinetics studies.展开更多
Objective: To investigate the role of ClC-3 chloride channel in the proliferation of breast cancer cell line Mcf-7 treated with curcumin and its specific mechanism. Methods: MTT assay was used to detect the effect of ...Objective: To investigate the role of ClC-3 chloride channel in the proliferation of breast cancer cell line Mcf-7 treated with curcumin and its specific mechanism. Methods: MTT assay was used to detect the effect of chloride channel blocker(DIDS) and curcumin on Mcf-7 and human normal cell viability. Patch-clamp technique was used to determine the current density before and after drug treatment. Apoptosis assay by flow cytometry was performed for further examination of cell apoptosis. Results: Curcumin had toxicity on Mcf-7 and HUVEC cells and DIDS reduced the survival rate of Mcf-7 cells by inhibiting proliferation. Curcumin could activate the chloride ion current on MCF-7 cell membrane, which would be inhibited by DIDS.Finally, curcumin in low concentration combined with DIDS could significantly promote the MCF-7 cells apoptosis. Conclusions: Our results suggest that ClC-3 protein is involved in the regulation of curcumin induced proliferation inhibiting in breast cancer cells through inducing cell apoptosis. ClC-3 may be a potential target of tumor therapy.展开更多
Calcium-activated chloride channels(CaCCs) are the crucial regulators of transepithelial fluid secretion, smooth muscle contraction and sensory transduction. Recently, compelling evidence has indicated that TMEM16A...Calcium-activated chloride channels(CaCCs) are the crucial regulators of transepithelial fluid secretion, smooth muscle contraction and sensory transduction. Recently, compelling evidence has indicated that TMEM16A(ANO1 or anoctamin-1) is a bona fide calcium-acvtivated chloride channel. A few small molecule CaCCs regulators are available for functional and therapeutic studies. We screened 126 natural compounds from Chinese herbs. Screening was performed with an iodide influx assay in Fischer rat thyroid epithelial cells to coexpress ANO1 and an iodide-sensitive fluorescent indicator(EYFP-H148Q/I152L). Imperatorin, a coumarin compound, was identified to inhibit ANO1-mediated chloride transport activated by multiple calcium-elevating agonists. The inhibitory effect is dose-dependent with IC50~14.63 μmol/L. Interestingly, imperatorin activated CFTR chloride channel with EC50~35.52 μmol/L. The adverse effects of imperatorin on CaCC and CFTR chloride channels will make it useful in pharmacological dissection of chloride transport in airway and intestinal epithelium. Further studies are required to evaluate the therapeutic effects of imperatorin on hypertension, asthma and certain tumors.展开更多
The cystic fibrosis transmembrane conductance regulator (CFFR) is a cAMP-activated chloride channel expressed in intestinal exoerine glands, which plays a key role in intestinal fluid secretion. A natural anthraquin...The cystic fibrosis transmembrane conductance regulator (CFFR) is a cAMP-activated chloride channel expressed in intestinal exoerine glands, which plays a key role in intestinal fluid secretion. A natural anthraquinone ac tivator of CFTR Cl^- channel, rhein, was identified by screening 217 single compounds from Chinese herbs via a cellbased halide-sensitive fluorescent assay. Rhein activates CFTR Cl^- transportation in a dose-dependent manner in the presence of cAMP with a physiological concentration. This study provides a novel molecular pharmacological mechanism for the laxative drugs in Treditional Chinese Medicine such as aloe, cascara and senna.展开更多
In this paper,we study the complicated dynamics of general Morris-Lecar model with the impact of Cl<sup>-</sup> fluctuations on firing patterns of this neuron model. After adding Cl<sup>-</sup>...In this paper,we study the complicated dynamics of general Morris-Lecar model with the impact of Cl<sup>-</sup> fluctuations on firing patterns of this neuron model. After adding Cl<sup>-</sup> channel in the original Morris-Lecar model, the dynamics of the original model such as its bifurcations of equilibrium points would be changed and they occurred at different values compared to the primary model. We discover these qualitative changes in the point of dynamical systems and neuroscience. We will conduct the co-dimension two bifurcations analysis with respect to different control parameters to explore the complicated behaviors for this new neuron model.展开更多
Vascular smooth muscle cells(VSMCs) are the major component of vascular wall which are often stretched and compressed by pounding intravascular pressure.These mechanical signals are usually transformed to electrical...Vascular smooth muscle cells(VSMCs) are the major component of vascular wall which are often stretched and compressed by pounding intravascular pressure.These mechanical signals are usually transformed to electrical signals by the opening or closing of ion channels in VSNCs and endothelial cells.Intravascular pressure causes a graded membrane potential depolarization of the VSMCs and leads to vasoconstriction(i.e.,myogenic response),independent of the vascular endothelium. Although the important role of cation channels including L-type Ca<sup>2+</sup> channels,K<sup>+</sup> channels,and TRP channels in the regulation of vascular tone has been well established the functional roles played by Cl<sup>-</sup> channels in the regulation of the membrane potential and vascular tone remain essentially obscure. Recent emerging evidence implicates very important roles of Cl<sup>-</sup> channels in vascular function ranging from the control of membrane potential equilibrium, vascular contraction and relaxation to the regulation of intracellular pH,cell volume homeostasis,cell proliferation,migration,and apoptosis.展开更多
Background Chronic obstructive pulmonary disease (COPD) is usually complicated with mucus overproduction in airway. Recently the increased expression of the human calcium-activated chloride channel 1 (CaCC1) was f...Background Chronic obstructive pulmonary disease (COPD) is usually complicated with mucus overproduction in airway. Recently the increased expression of the human calcium-activated chloride channel 1 (CaCC1) was found to play an important role in mucus overproduction in the asthmatic airways. To investigate the relationship of CaCC1 and mucus overproduction in the airway of Chinese patients with COPD, the expressions of CaCC1, MUC5AC and mucus in bronchial tissues were examined. Methods Bronchial tissues were obtained from fiberoptic bronchoscopy and bronchial biopsy in West China Hospital from April to July in 2004. Twenty-five patients were diagnosed as the patients with COPD overproduction, and other 20 were the control subjects. The expressions of CaCC1, MUC5AC and mucin in bronchial tissues were detected by reverse transcriptase-polymerase chain reaction (RT-PCR), in situ hybridization with digoxigenin (DIG)-Iabeled RNA probe, immunohistochemical and alcian blue-periodic acid Schiff (AB-PAS) staining, respectively. Results Compared with the control group, the stronger expressions of CaCC1 were further detected throughout the bronchial tissues from patients with COPD (P〈0.01). Furthermore, the stronger expressions of the CaCC1 mRNA were related to the severity of airflow obstruction. Samples from COPD showed a stronger staining for MUC5AC than those in control subjects (P〈0.01) and AB-PAS staining revealed more mucins in COPD patients' submucosal gland comparing with that in control subjects (P〈0.01). Expression levels of the CaCC1 mRNA were respectively negatively correlated with the patients' forced expiratory volume in one second (FEV~) / forced vital capacity (FVC) data, FEV1% predicted data, V50% predicted data, V25% predicted data (r=-0.43, r=-0.43, r=-0.35, r=-0.36, P〈0.01, P〈0.01, P〈0.05, P〈0.05). While the expression levels of the CaCC1 mRNA were well correlated with the expression levels of the MUC5AC mRNA of airway epithelium and the PAS-AB stained area of submucosal glands (r=0.39, r=0.46, P〈0.05, P〈0.01). Expression levels of the MUC5AC mRNA were negatively correlated with the patients' FEV1/FVC data (P=0.01), FEV1% pred data (P=-0.01), V50% predicted data, V25% predicted data(r=-0.53, r=-0.53, r=-0.48, r=-0.43, P〈0.01, P〈0.01, P〈0.01, P〈0.01). While the expression levels of the MUC5AC mRNA were well correlated with the positively PAS-AB stained area of submucosal gland (P〈0.05), and the correlation coefficients were 0.43. Conclusion These results suggest that the stronger gene expression of CaCC1 exists, complicated with mucus overproduction in the airwav of Chinese patients with COPD.展开更多
AIM: To investigate the mechanisms of chloride intracellular channel 1 (CLIC1) in the metastasis of colon cancer under hypoxia-reoxygenation (H-R) conditions.
Human spermatozoa encounter an osmotic decrease from 330 to 290 mOsm I-z when passing through the female reproductive tract. We aimed to evaluate the role of chloride channels in volume regulation and sperm motility f...Human spermatozoa encounter an osmotic decrease from 330 to 290 mOsm I-z when passing through the female reproductive tract. We aimed to evaluate the role of chloride channels in volume regulation and sperm motility from patients with asthenozoospermia. Spermatozoa were purified using Percoll density gradients. Sperm volume was measured as the forward scatter signal using flow cytometry. Sperm motility was analyzed using computer-aided sperm analysis (CASA). When transferred from an isotonic solution (330 mOsm I-z) to a hypotonic solution (290 mOsm I-Z), cell volume was not changed in spermatozoa from normozoospermic men; but increased in those from asthenozoospermic samples. The addition of the chloride channel blockers, 4,4'-diisothiocyanatostilbene-2,2'- isulfonic acid (DIDS) or 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) to the hypotonic solution caused the normal spermatozoa to swell but did not increase the volume of those from the asthenozoospermic semen. DIDS and NPPB decreased sperm motility in both sets of semen samples. The inhibitory effect of NPPB on normal sperm motility was much stronger than on spermatozoa from the asthenozoospermic samples. Both sperm types expressed CIC-3 chloride channels, but the expression levels in the asthenozoospermic samples were much lower, especially in the neck and mid-piece areas. Spermatozoa from men with asthenozoospermia demonstrated lower volume regulating capacity, mobility, and CIC-3 expression levels (especially in the neck) than did normal spermatozoa. Thus, chloride channels play important roles in the regulation of sperm volume and motility and are downregulated in cases of asthenozoospermia.展开更多
Objective:To investigate the mechanisms of electroacupuncture(EA)at Zusanli(ST 36),Liangmen(ST 21)and Sanyinjiao(SP 6)in intervening diabetic gastroparesis(DGP)based on calcium-activated chloride channel.Methods:Forty...Objective:To investigate the mechanisms of electroacupuncture(EA)at Zusanli(ST 36),Liangmen(ST 21)and Sanyinjiao(SP 6)in intervening diabetic gastroparesis(DGP)based on calcium-activated chloride channel.Methods:Forty Sprague-Dawley rats were randomly divided into four groups,including a normal control group(group A),a model group(group B),an EA group(group C)and a metoclopramide group(group D),with 10 rats in each group.A single intraperitoneal injection of 2%streptozotocin(STZ)combined with 8-week high-glucose high-fat diet was used to establish a DGP rat model.After intervention,gastrointestinal propulsive rate was observed;the expression level of transmembrane protein 16A(TMEM16A)was examined by immunohistochemistry;the Ca2+concentration in interstitial cells of Cajal(ICCs)was detected by immunofluorescence;and whole-cell patch-clamp technique was applied to detect the current intensity of calcium-activated chloride channel(ICaCC)in ICCs in gastric antrum.Results:After modeling,the blood glucose levels in group B,group C and group D were significantly increased compared with group A(all P<0.01);after intervention,compared with group B,the blood glucose levels in group C and group D were significantly decreased(P<0.05,P<0.01);the intra-group comparison of blood glucose level between after modeling and after intervention found significant difference only in group C(P<0.01).The gastrointestinal propulsive rates in group B,group C and group D were significantly different from that in group A(P<0.01 or P<0.05);the gastrointestinal propulsive rates were markedly higher in group C and group D than in group B(P<0.01,P<0.01).The expressions of TMEM16A in group B and group C were decreased compared with group A(P<0.01,P<0.05);the expressions of TMEM16A in group C and group D were increased compared with group B(P<0.01,P<0.05).The fluorescence intensity of Ca2+was significantly lower in group B than in group A(P<0.01);the fluorescence intensity of Ca2+was significantly higher in group C and group D than in group B(P<0.01,P<0.05).ICaCC in ICCs in group B was significantly decreased compared with group A;ICaCC in group C and group D were increased compared with group B.Conclusion:EA at Zusanli(ST 36),Liangmen(ST 21)and Sanyinjiao(SP 6)can significantly improve gastrointestinal motility in DGP rats by up-regulating the ICaCC in ICCs.展开更多
Platelet activation plays an important role in thrombosis. Platelet glycoprotein Ⅱ b/Ⅲ a ( GPⅡ b/Ⅲ a ) is the receptor of fibrinogen. Platelet cross-linking with fibrinogen through GP Ⅱ b/Ⅲ a is the process of...Platelet activation plays an important role in thrombosis. Platelet glycoprotein Ⅱ b/Ⅲ a ( GPⅡ b/Ⅲ a ) is the receptor of fibrinogen. Platelet cross-linking with fibrinogen through GP Ⅱ b/Ⅲ a is the process of thrombosis. Ca^2+ is an important intracellular second messenger in platelet activation. It has been reported that GP Ⅱ b/Ⅲ a receptors were involved in the calcium influx of activated platelet, and GP Ⅱ b/Ⅲ a receptor had characteristics of calcium channel or an adjacent calcium channel.展开更多
Background Expression of murine calcium-activated chloride channel family member 3 (mCLCA3) has been reported to be increased in the airway epithelium of asthmatic mice challenged with ovalbumin (OVA). However, it...Background Expression of murine calcium-activated chloride channel family member 3 (mCLCA3) has been reported to be increased in the airway epithelium of asthmatic mice challenged with ovalbumin (OVA). However, its role in asthmatic airway inflammation under no OVA exposure has not yet been clarified. Methods mCLCA3 plasmids were transfected into the airways of normal BALB/c mice. mCLCA3 expression and airway inflammation in mouse lung tissue were evaluated. Cell differentials and cytokines in bronchoalveolar lavage fluid (BALF) were analyzed. The expression of mCLCA3 protein and mucus protein mucin-5 subtype AC (MUC5AC) were analyzed by Western blotting. The mRNA levels of mCLCA3, MUC5AC and interleukin-13 (IL-13) were determined quantitatively. Results mCLCA3 expression was not detected in the control group while strong immunoreactivity was detected in the OVA and mCLCA3 plasmid groups, and was strictly localized to the airway epithelium. The numbers of inflammatory cells in lung tissue and BALF were increased in both mCLCA3 plasmid and OVA groups. The protein and mRNA levels of mCLCA3 and MUC5AC in the lung tissue were significantly increased in the mCLCA3 plasmid and OVA groups compared to the control group. The level of IL-13, but not IL-4, IL-5, IFN-y, CCL2, CCL5 or CCL11, was significantly increased compared with control group in BALF in the mCLCA3 plasmid and OVA groups. The level of IL-13 in the BALF in the mCLCA3 plasmid group was much higher than that in the OVA group (P 〈0.05). The level of mCLCA3 mRNA in lung tissue was positively correlated with the levels of MUC5AC mRNA in lung tissue, IL-13 mRNA in lung tissue, the number of eosinophils in BALF, and the content of IL-13 protein in BALE The level of IL-13 mRNA in lung tissue was positively correlated with the number of eosinophils in BALF and the level of MUC5AC mRNA in lung tissue. Conclusion These findings suggest that increased expression of a single-gene, mCLCA3, could simulate an asthma attack, and its mechanism may involve mCLCA3 overexpression up-regulating IL-13 expression.展开更多
AIM:To investigate the effect of chloride intracellular channel 1(CLIC1) on the cell proliferation,apoptosis,migration and invasion of gastric cancer cells.METHODS:CLIC1 expression was evaluated in human gastric cance...AIM:To investigate the effect of chloride intracellular channel 1(CLIC1) on the cell proliferation,apoptosis,migration and invasion of gastric cancer cells.METHODS:CLIC1 expression was evaluated in human gastric cancer cell lines SGC-7901 and MGC-803 by real time polymerase chain reaction(RT-PCR).Four segments of small interference RNA(siRNA) targeting CLIC1 mRNA and a no-sense control segment were designed by bioinformatics technology.CLIC1 siRNA was selected using Lipofectamine 2000 and transfected transiently into human gastric cancer SGC-7901 and MGC-803 cells.The transfected efficiency was observed under fluorescence microscope.After transfection,mRNA expression of CLIC1 was detected with RT-PCR and Western blotting was used to detect the protein expression.Proliferation was examined by methyl thiazolyl tetrazolium and apoptosis was detected with flow cytometry.Polycarbonate membrane transwell chamber and Matrigel were used for the detection of the changes of invasion and migration of the two cell lines.RESULTS:In gastric cancer cell lines SGC-7901 and MGC-803,CLIC1 was obviously expressed and CLIC1 siRNA could effectively suppress the expression of CLIC1 protein and mRNA.Proliferation of cells transfected with CLIC1 siRNA3 was enhanced notably,and the highest proliferation rate was 23.3%(P = 0.002) in SGC-7901 and 35.55%(P = 0.001) in MGC-803 cells at 48 h.The G2/M phase proportion increased,while G0/G1 and S phase proportions decreased.The apoptotic rate of the CLIC1 siRNA3 group obviously decreased in both SGC-7901 cells(62.24%,P = 0.000) and MGC-803 cells(52.67%,P = 0.004).Down-regulation of CLIC1 led to the inhibition of invasion and migration by 54.31%(P = 0.000) and 33.62%(P = 0.001) in SGC-7901 and 40.74%(P = 0.000) and 29.26%(P = 0.002) in MGC-803.However,there was no significant difference between the mock group cells and the negative control group cells.展开更多
Previous studies have demonstrated that increased chloride channel activity plays a role in nitric oxide-induced neuronal apoptosis in the rat hippocampus. The present study investigated the effects of the broad-spect...Previous studies have demonstrated that increased chloride channel activity plays a role in nitric oxide-induced neuronal apoptosis in the rat hippocampus. The present study investigated the effects of the broad-spectrum calcium channel blocker CdCI2 on survival rate, percentage of apoptosis, and morphological changes in hippocampal neurons cultured in vitro, as well as the effects of calcium channels on neuronal apoptosis. The chloride channel blockers 4-acetamido-4'-isothiocyanatostilbene-2, 2'-disulfonic acid (SITS) or 4, 4'-diisethiocyanostilbene-2, 2'-disulfonic acid (DIDS) increased the survival rate of 3-morpholinosydnonimine (SIN-1)-treated neurons and suppressed SIN-l-induced neuronal apoptosis. The calcium channel blocker CdCI2 did not increase the survival rate of neurons and did not affect SIN-l-induced apoptosis or SITS- or DIDS-suppressed neuronal apoptosis. Results demonstrated that calcium channels did not significantly affect neuronal apoptosis.展开更多
基金Supported by the Natural Science Foundation of Guangxi Province(Nos.2023 GXNSFAA 026503,2018 GXNSFBA281201)the Guangxi Key Research and Development Program(No.GuikeAB21196030)+3 种基金the Marine Science Guangxi First-Class Subject,Beibu Gulf University(No.DRC002)the Scientific Research and Technology Development Plan Project of Qinzhou(Nos.202014842,20223637)the Science and Technology Major Project of Guangxi Province(No.AA17204095-10)the Guangxi Key Laboratory of Beibu Gulf Marine Biodiversity Conservation,Beibu Gulf University(Nos.2020ZB09,2020ZB04)。
文摘The chloride channel 7 gene(CLC 7)of the Hong Kong oyster Crassostrea hongkongensis was cloned and named ChCLC 7.The cDNA was 2572 bp in length,with a 5′non-coding region containing 25 bp,a 3′non-coding region containing 327 bp,and an open reading frame of 2298 bp.ChCLC 7 has 96.8%and 92.1%homology with CLC 7 of Crassostrea gigas and Crassostrea virginica,respectively,and it was clustered with CLC 7 of C.gigas and C.virginica.QRT-PCR showed that ChCLC 7 was expressed in all eight tissues,with the highest in adductor muscle and second in gill.The ChCLC 7 expression pattern in gill was altered significantly under high salinity stress with an overall upward and then downward trend.After RNA interference,the expression of ChCLC 7 and survival rate of oyster under high salinity stress was reduced significantly,and so did the concentration of hemolymph chloride ion in 48-96 h after RNA interference.We believed that ChCLC 7 could play an important role in osmoregulation of C.hongkongensis by regulating Cl^(-)transport.This study provided data for the analysis of molecular mechanism against oyster salinity stress.
文摘Objective A calcium-activated chloride current (ICl(Ca)) has been observed in medium-sized sensory neurons of the dorsal root ganglion (DRG). Axotomy of the sciatic nerve induces a similar current in the majority of medium and large diameter neurons. Our aim is to identify the molecule(s) underlying this current. Methods Using conventional and quantitative RT-PCR, we examined the expression in DRG of members of three families of genes, which have been shown to have latch) current inducing properties. Results We showed the detection of transcripts representing several members of these families, i.e. chloride channel calciumactivated (CLCA), Bestrophin and Tweety gene families in adult DRG, in the normal state and 3 d after sciatic nerve section, a model for peripheral nerve injury. Conclusion Our analysis revealed that that mBestl and Tweety2 appear as the best candidates to play a role in the injury-induced Icl(Ca) in DRG neurons.
基金the Science and Technology Department of Guizhou Province,No. (2007)2127the Key Development Program of Science and Technology Department of Guizhou Province,No. [2009]3075A Grant from the Science and Technology Department of Zhuhai,No. PC20081010
文摘BACKGROUND:Chloride channels participate in non-neuronal apoptosis.However,it remains unclear whether chloride channels are involved in ischemic neuronal apoptosis.OBJECTIVE:To explore the effects of 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid (SITS) and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS),two chloride channel blockers,on the hippocampal neuronal apoptosis induced by 3-morpholinosydnonimine (SIN-1) based on the nitric oxide toxicity theory of neuronal apoptosis following ischemic brain injury.DESIGN,TIME AND SETTING:Comparative observation and in vitro experiments were performed at the laboratory of Zhuhai Campus of Zunyi Medical College from January to May 2009.MATERIALS:SIN-1,SITS,and DIDS were purchased from Sigma,USA.METHODS:Hippocampal neurons from Sprague-Dawley rats,aged 1 day,were cultured In vitro for 12 days and randomly assigned to control,SIN-1,or chloride channel blocker groups.SIN-1 group neurons were induced by SIN-1 for 18 hours to establish a model of ischemic neuronal apoptosis.Neurons in chloride channel blocker groups were treated with SITS or DIDS plus SIN-1 for 18 hours.The controls were cultured in DMEM/Ham's F12 complete medium alone.MAIN OUTCOME MEASURES:The apoptotic neurons and nuclear appearance were detected by Hoechst 33258 fluorescence staining; neuronal viability was quantitatively determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis.Caspase-3 activity was analyzed by Western blot.RESULTS:SIN-1 (1 mmol/L) dramatically induced apoptosis (50%-60%).SITS and DIDS inhibited nitric oxide-induced neuronal injury in a dose-dependent manner,suppressed caspase-3 activation,reduced neuronal apoptosis,and improved neuronal survival.CONCLUSION:Chloride channel blockers can protect against neuronal injury induced by NO.Chloride channels might be involved in neuronal apoptosis following cerebral ischemia.
基金supported by the National Natural Science Foundation of China,No.81160157a grant from Guizhou Science and Technology Department in China,No.SY20093075Technological Talents Funds of Guizhou Province in China,No.201209
文摘Over-production of nitric oxide is pathogenic for neuronal apoptosis around the ischemic area fol- lowing ischemic brain injury. In this study, an apoptotic model in rat hippocampal neurons was es- tablished by 0.5 mmol/L 3-morpholinosyndnomine (SIN-l), a nitric oxide donor. The models were then cultured with 0.1 mmol/L of 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS; the chloride channel blocker)for 18 hours. Neuronal survival was detected using the 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and apoptosis was assayed by Hoechst 33342-labeled neuronal DNA fluorescence staining. Western blot analysis and immunochemilumi- nescence staining were applied to determine the changes of activated caspase-3 and CIC-3 channel proteins. Real-time PCR was used to detect the mRNA expression of CIC-3. The results showed that SIN-1 reduced the neuronal survival rate, induced neuronal apoptosis, and promoted CIC-3 chloride channel protein and mRNA expression in the apoptotic neurons. DIDS reversed the effect of SIN-I. Our findings indicate that the increased activities of the CIC-3 chloride channel may be involved in hippocampal neuronal apoptosis induced by nitric oxide.
基金supported by the National Natural Science Foundation of China, No. 81160157projects of Science and Technology Bureau of Guizhou Province, No.20093075, 20072127
文摘Apoptosis in cultured rat hippocampal neurons was induced using the nitric oxide donor 3-morpholinosydnonimine, and cells were treated with the chloride channel blocker, 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid. Results showed that the survival rate of neurons was significantly increased after treatment with 4,4-diisothiocyanatostilbene-2,2'-disulfonic acid, and the rate of apoptosis decreased. In addition, the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor were significantly reduced. Our experimental findings indicate that the chloride channel blocker 4,4- diisothiocyanatostilbene-2,2'-disulfonic acid can antagonize apoptotic cell death of hippocampal neurons by inhibiting the expression of the apoptosis-related proteins poly(adenosine diphosphate-ribose)polymerase-1 and apoptosis-inducing factor.
基金the Science and Technology Development Program of Jilin Province, No.20050407-6
文摘Using whole-cell patch-clamp recordings, the effects of antigliomatin were observed on chloride channels on C6 glioma cells cultured in vitro. Antigliomatin was extracted from the venom of the scorpion Buthus martensii Karsch. Chloride channels are closed under normal osmotic pressure. When osmotic pressure was reduced to 120, 110 and 100 mV, the cell volume enlarged, chloride channels opened, and the chloride channel current increased. Three minutes after antigliomatin treatment, the chloride channel current decreased in a dose-dependent manner. These results show that antigliomatin extracted from the venom of the scorpion Buthus martensii Karsch diminishes chloride channel currents on C6 glioma cells.
文摘A thiazolidinone CFTR inhibitor(CFTR_ inh-172 ) was synthesized by a three-step procedure with trifluromethylaniline as the starting material. The synthesized CFTR inhibitor was characterized structurally by means of 1H NMR and functionally in a CFTR-expressing cell line FRT/hCFTR/EYFP-H148Q by both fluorescent and electrophysiological methods. A large amount(100 g) of high-quality small molecule thiazolidinone CFTR chloride channel inhibitor,CFTR_ inh-172 ,can be produced with this simple three-step synthetic procedure. The structure of the final product 2-thioxo-3-(3-trifluromethylphenyl)-5-[4-carboxyphenyl- methylene]-4-thiazolidinone was confirmed by 1H NMR. The overall yield was 58% with a purity over 99% as analyzed by HPLC. The synthesized CFTR_ inh-172 specifically inhibited CFTR chloride channel function in a cell-based fluorescence assay( K _d≈1.5 μmol/L) and in a Ussing chamber-based short-circuit current assay( K _d≈0.2 μmol/L),indicating better quality than that of the commercial combinatorial compound. The synthesized inhibitor is nontoxic to cultured cells at a high concentration and to mouse at a high dose. The synthetic procedure developed here can be used to produce a large amount of the high-quality CFTR_ inh-172 suitable for antidiarrheal studies and for creation of cystic fibrosis models in large animals. The procedure can be used to synthesize radiolabled CFTR_ inh-172 for in vivo pharmacokinetics studies.
基金funded by grants from the Science and Technology Planning Projeet of Guangdong Province (2014A020211022)Technology Planning Project of Guangzhou (201510010074.201607010063 and 201607010216)
文摘Objective: To investigate the role of ClC-3 chloride channel in the proliferation of breast cancer cell line Mcf-7 treated with curcumin and its specific mechanism. Methods: MTT assay was used to detect the effect of chloride channel blocker(DIDS) and curcumin on Mcf-7 and human normal cell viability. Patch-clamp technique was used to determine the current density before and after drug treatment. Apoptosis assay by flow cytometry was performed for further examination of cell apoptosis. Results: Curcumin had toxicity on Mcf-7 and HUVEC cells and DIDS reduced the survival rate of Mcf-7 cells by inhibiting proliferation. Curcumin could activate the chloride ion current on MCF-7 cell membrane, which would be inhibited by DIDS.Finally, curcumin in low concentration combined with DIDS could significantly promote the MCF-7 cells apoptosis. Conclusions: Our results suggest that ClC-3 protein is involved in the regulation of curcumin induced proliferation inhibiting in breast cancer cells through inducing cell apoptosis. ClC-3 may be a potential target of tumor therapy.
基金Supported by the National Natural Science Foundation of China(Nos.30670477, 30973577 and 30770493)the National Basic Research Program of China(No.2009CB521908)
文摘Calcium-activated chloride channels(CaCCs) are the crucial regulators of transepithelial fluid secretion, smooth muscle contraction and sensory transduction. Recently, compelling evidence has indicated that TMEM16A(ANO1 or anoctamin-1) is a bona fide calcium-acvtivated chloride channel. A few small molecule CaCCs regulators are available for functional and therapeutic studies. We screened 126 natural compounds from Chinese herbs. Screening was performed with an iodide influx assay in Fischer rat thyroid epithelial cells to coexpress ANO1 and an iodide-sensitive fluorescent indicator(EYFP-H148Q/I152L). Imperatorin, a coumarin compound, was identified to inhibit ANO1-mediated chloride transport activated by multiple calcium-elevating agonists. The inhibitory effect is dose-dependent with IC50~14.63 μmol/L. Interestingly, imperatorin activated CFTR chloride channel with EC50~35.52 μmol/L. The adverse effects of imperatorin on CaCC and CFTR chloride channels will make it useful in pharmacological dissection of chloride transport in airway and intestinal epithelium. Further studies are required to evaluate the therapeutic effects of imperatorin on hypertension, asthma and certain tumors.
文摘The cystic fibrosis transmembrane conductance regulator (CFFR) is a cAMP-activated chloride channel expressed in intestinal exoerine glands, which plays a key role in intestinal fluid secretion. A natural anthraquinone ac tivator of CFTR Cl^- channel, rhein, was identified by screening 217 single compounds from Chinese herbs via a cellbased halide-sensitive fluorescent assay. Rhein activates CFTR Cl^- transportation in a dose-dependent manner in the presence of cAMP with a physiological concentration. This study provides a novel molecular pharmacological mechanism for the laxative drugs in Treditional Chinese Medicine such as aloe, cascara and senna.
文摘In this paper,we study the complicated dynamics of general Morris-Lecar model with the impact of Cl<sup>-</sup> fluctuations on firing patterns of this neuron model. After adding Cl<sup>-</sup> channel in the original Morris-Lecar model, the dynamics of the original model such as its bifurcations of equilibrium points would be changed and they occurred at different values compared to the primary model. We discover these qualitative changes in the point of dynamical systems and neuroscience. We will conduct the co-dimension two bifurcations analysis with respect to different control parameters to explore the complicated behaviors for this new neuron model.
文摘Vascular smooth muscle cells(VSMCs) are the major component of vascular wall which are often stretched and compressed by pounding intravascular pressure.These mechanical signals are usually transformed to electrical signals by the opening or closing of ion channels in VSNCs and endothelial cells.Intravascular pressure causes a graded membrane potential depolarization of the VSMCs and leads to vasoconstriction(i.e.,myogenic response),independent of the vascular endothelium. Although the important role of cation channels including L-type Ca<sup>2+</sup> channels,K<sup>+</sup> channels,and TRP channels in the regulation of vascular tone has been well established the functional roles played by Cl<sup>-</sup> channels in the regulation of the membrane potential and vascular tone remain essentially obscure. Recent emerging evidence implicates very important roles of Cl<sup>-</sup> channels in vascular function ranging from the control of membrane potential equilibrium, vascular contraction and relaxation to the regulation of intracellular pH,cell volume homeostasis,cell proliferation,migration,and apoptosis.
基金the grants from Natural Science Foundation of China and from China Medical Board of New York to Dr. F.Q. Wen(No.30425007,30370627,00-722,06-838)
文摘Background Chronic obstructive pulmonary disease (COPD) is usually complicated with mucus overproduction in airway. Recently the increased expression of the human calcium-activated chloride channel 1 (CaCC1) was found to play an important role in mucus overproduction in the asthmatic airways. To investigate the relationship of CaCC1 and mucus overproduction in the airway of Chinese patients with COPD, the expressions of CaCC1, MUC5AC and mucus in bronchial tissues were examined. Methods Bronchial tissues were obtained from fiberoptic bronchoscopy and bronchial biopsy in West China Hospital from April to July in 2004. Twenty-five patients were diagnosed as the patients with COPD overproduction, and other 20 were the control subjects. The expressions of CaCC1, MUC5AC and mucin in bronchial tissues were detected by reverse transcriptase-polymerase chain reaction (RT-PCR), in situ hybridization with digoxigenin (DIG)-Iabeled RNA probe, immunohistochemical and alcian blue-periodic acid Schiff (AB-PAS) staining, respectively. Results Compared with the control group, the stronger expressions of CaCC1 were further detected throughout the bronchial tissues from patients with COPD (P〈0.01). Furthermore, the stronger expressions of the CaCC1 mRNA were related to the severity of airflow obstruction. Samples from COPD showed a stronger staining for MUC5AC than those in control subjects (P〈0.01) and AB-PAS staining revealed more mucins in COPD patients' submucosal gland comparing with that in control subjects (P〈0.01). Expression levels of the CaCC1 mRNA were respectively negatively correlated with the patients' forced expiratory volume in one second (FEV~) / forced vital capacity (FVC) data, FEV1% predicted data, V50% predicted data, V25% predicted data (r=-0.43, r=-0.43, r=-0.35, r=-0.36, P〈0.01, P〈0.01, P〈0.05, P〈0.05). While the expression levels of the CaCC1 mRNA were well correlated with the expression levels of the MUC5AC mRNA of airway epithelium and the PAS-AB stained area of submucosal glands (r=0.39, r=0.46, P〈0.05, P〈0.01). Expression levels of the MUC5AC mRNA were negatively correlated with the patients' FEV1/FVC data (P=0.01), FEV1% pred data (P=-0.01), V50% predicted data, V25% predicted data(r=-0.53, r=-0.53, r=-0.48, r=-0.43, P〈0.01, P〈0.01, P〈0.01, P〈0.01). While the expression levels of the MUC5AC mRNA were well correlated with the positively PAS-AB stained area of submucosal gland (P〈0.05), and the correlation coefficients were 0.43. Conclusion These results suggest that the stronger gene expression of CaCC1 exists, complicated with mucus overproduction in the airwav of Chinese patients with COPD.
基金Supported by The "Eleventh Five-year Plan" for Medical Sci-ence Development of PLA,No.06MB243the National Natural Science Foundation of China,No.81101101 and No.51273165+1 种基金the Key Project of Chinese Ministry of Education,No.212149the Projects of Sichuan Province,No.2010SZ0294,No.2011JQ0032 and No.12ZB038
文摘AIM: To investigate the mechanisms of chloride intracellular channel 1 (CLIC1) in the metastasis of colon cancer under hypoxia-reoxygenation (H-R) conditions.
文摘Human spermatozoa encounter an osmotic decrease from 330 to 290 mOsm I-z when passing through the female reproductive tract. We aimed to evaluate the role of chloride channels in volume regulation and sperm motility from patients with asthenozoospermia. Spermatozoa were purified using Percoll density gradients. Sperm volume was measured as the forward scatter signal using flow cytometry. Sperm motility was analyzed using computer-aided sperm analysis (CASA). When transferred from an isotonic solution (330 mOsm I-z) to a hypotonic solution (290 mOsm I-Z), cell volume was not changed in spermatozoa from normozoospermic men; but increased in those from asthenozoospermic samples. The addition of the chloride channel blockers, 4,4'-diisothiocyanatostilbene-2,2'- isulfonic acid (DIDS) or 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) to the hypotonic solution caused the normal spermatozoa to swell but did not increase the volume of those from the asthenozoospermic semen. DIDS and NPPB decreased sperm motility in both sets of semen samples. The inhibitory effect of NPPB on normal sperm motility was much stronger than on spermatozoa from the asthenozoospermic samples. Both sperm types expressed CIC-3 chloride channels, but the expression levels in the asthenozoospermic samples were much lower, especially in the neck and mid-piece areas. Spermatozoa from men with asthenozoospermia demonstrated lower volume regulating capacity, mobility, and CIC-3 expression levels (especially in the neck) than did normal spermatozoa. Thus, chloride channels play important roles in the regulation of sperm volume and motility and are downregulated in cases of asthenozoospermia.
文摘Objective:To investigate the mechanisms of electroacupuncture(EA)at Zusanli(ST 36),Liangmen(ST 21)and Sanyinjiao(SP 6)in intervening diabetic gastroparesis(DGP)based on calcium-activated chloride channel.Methods:Forty Sprague-Dawley rats were randomly divided into four groups,including a normal control group(group A),a model group(group B),an EA group(group C)and a metoclopramide group(group D),with 10 rats in each group.A single intraperitoneal injection of 2%streptozotocin(STZ)combined with 8-week high-glucose high-fat diet was used to establish a DGP rat model.After intervention,gastrointestinal propulsive rate was observed;the expression level of transmembrane protein 16A(TMEM16A)was examined by immunohistochemistry;the Ca2+concentration in interstitial cells of Cajal(ICCs)was detected by immunofluorescence;and whole-cell patch-clamp technique was applied to detect the current intensity of calcium-activated chloride channel(ICaCC)in ICCs in gastric antrum.Results:After modeling,the blood glucose levels in group B,group C and group D were significantly increased compared with group A(all P<0.01);after intervention,compared with group B,the blood glucose levels in group C and group D were significantly decreased(P<0.05,P<0.01);the intra-group comparison of blood glucose level between after modeling and after intervention found significant difference only in group C(P<0.01).The gastrointestinal propulsive rates in group B,group C and group D were significantly different from that in group A(P<0.01 or P<0.05);the gastrointestinal propulsive rates were markedly higher in group C and group D than in group B(P<0.01,P<0.01).The expressions of TMEM16A in group B and group C were decreased compared with group A(P<0.01,P<0.05);the expressions of TMEM16A in group C and group D were increased compared with group B(P<0.01,P<0.05).The fluorescence intensity of Ca2+was significantly lower in group B than in group A(P<0.01);the fluorescence intensity of Ca2+was significantly higher in group C and group D than in group B(P<0.01,P<0.05).ICaCC in ICCs in group B was significantly decreased compared with group A;ICaCC in group C and group D were increased compared with group B.Conclusion:EA at Zusanli(ST 36),Liangmen(ST 21)and Sanyinjiao(SP 6)can significantly improve gastrointestinal motility in DGP rats by up-regulating the ICaCC in ICCs.
文摘Platelet activation plays an important role in thrombosis. Platelet glycoprotein Ⅱ b/Ⅲ a ( GPⅡ b/Ⅲ a ) is the receptor of fibrinogen. Platelet cross-linking with fibrinogen through GP Ⅱ b/Ⅲ a is the process of thrombosis. Ca^2+ is an important intracellular second messenger in platelet activation. It has been reported that GP Ⅱ b/Ⅲ a receptors were involved in the calcium influx of activated platelet, and GP Ⅱ b/Ⅲ a receptor had characteristics of calcium channel or an adjacent calcium channel.
基金This work was supported by a grant from the National Natural Science Foundation of China (No. 30500224).
文摘Background Expression of murine calcium-activated chloride channel family member 3 (mCLCA3) has been reported to be increased in the airway epithelium of asthmatic mice challenged with ovalbumin (OVA). However, its role in asthmatic airway inflammation under no OVA exposure has not yet been clarified. Methods mCLCA3 plasmids were transfected into the airways of normal BALB/c mice. mCLCA3 expression and airway inflammation in mouse lung tissue were evaluated. Cell differentials and cytokines in bronchoalveolar lavage fluid (BALF) were analyzed. The expression of mCLCA3 protein and mucus protein mucin-5 subtype AC (MUC5AC) were analyzed by Western blotting. The mRNA levels of mCLCA3, MUC5AC and interleukin-13 (IL-13) were determined quantitatively. Results mCLCA3 expression was not detected in the control group while strong immunoreactivity was detected in the OVA and mCLCA3 plasmid groups, and was strictly localized to the airway epithelium. The numbers of inflammatory cells in lung tissue and BALF were increased in both mCLCA3 plasmid and OVA groups. The protein and mRNA levels of mCLCA3 and MUC5AC in the lung tissue were significantly increased in the mCLCA3 plasmid and OVA groups compared to the control group. The level of IL-13, but not IL-4, IL-5, IFN-y, CCL2, CCL5 or CCL11, was significantly increased compared with control group in BALF in the mCLCA3 plasmid and OVA groups. The level of IL-13 in the BALF in the mCLCA3 plasmid group was much higher than that in the OVA group (P 〈0.05). The level of mCLCA3 mRNA in lung tissue was positively correlated with the levels of MUC5AC mRNA in lung tissue, IL-13 mRNA in lung tissue, the number of eosinophils in BALF, and the content of IL-13 protein in BALE The level of IL-13 mRNA in lung tissue was positively correlated with the number of eosinophils in BALF and the level of MUC5AC mRNA in lung tissue. Conclusion These findings suggest that increased expression of a single-gene, mCLCA3, could simulate an asthma attack, and its mechanism may involve mCLCA3 overexpression up-regulating IL-13 expression.
基金Supported by The National Natural Science Foundation of China,No.30560151the Key Research Project of Guangxi Municipal Health Bureau,No.200824+1 种基金the Research Project of Guangxi Educational Department,No.201012MS062 and No. 2011105981002M204the Natural Science Foundation of Guangxi,No.0832113
文摘AIM:To investigate the effect of chloride intracellular channel 1(CLIC1) on the cell proliferation,apoptosis,migration and invasion of gastric cancer cells.METHODS:CLIC1 expression was evaluated in human gastric cancer cell lines SGC-7901 and MGC-803 by real time polymerase chain reaction(RT-PCR).Four segments of small interference RNA(siRNA) targeting CLIC1 mRNA and a no-sense control segment were designed by bioinformatics technology.CLIC1 siRNA was selected using Lipofectamine 2000 and transfected transiently into human gastric cancer SGC-7901 and MGC-803 cells.The transfected efficiency was observed under fluorescence microscope.After transfection,mRNA expression of CLIC1 was detected with RT-PCR and Western blotting was used to detect the protein expression.Proliferation was examined by methyl thiazolyl tetrazolium and apoptosis was detected with flow cytometry.Polycarbonate membrane transwell chamber and Matrigel were used for the detection of the changes of invasion and migration of the two cell lines.RESULTS:In gastric cancer cell lines SGC-7901 and MGC-803,CLIC1 was obviously expressed and CLIC1 siRNA could effectively suppress the expression of CLIC1 protein and mRNA.Proliferation of cells transfected with CLIC1 siRNA3 was enhanced notably,and the highest proliferation rate was 23.3%(P = 0.002) in SGC-7901 and 35.55%(P = 0.001) in MGC-803 cells at 48 h.The G2/M phase proportion increased,while G0/G1 and S phase proportions decreased.The apoptotic rate of the CLIC1 siRNA3 group obviously decreased in both SGC-7901 cells(62.24%,P = 0.000) and MGC-803 cells(52.67%,P = 0.004).Down-regulation of CLIC1 led to the inhibition of invasion and migration by 54.31%(P = 0.000) and 33.62%(P = 0.001) in SGC-7901 and 40.74%(P = 0.000) and 29.26%(P = 0.002) in MGC-803.However,there was no significant difference between the mock group cells and the negative control group cells.
基金Supported by the Science and Technology Department of Guizhou Province, No. C20072127, SY20093075the Science and Technology Department of Zhuhai City, No. PC20081010
文摘Previous studies have demonstrated that increased chloride channel activity plays a role in nitric oxide-induced neuronal apoptosis in the rat hippocampus. The present study investigated the effects of the broad-spectrum calcium channel blocker CdCI2 on survival rate, percentage of apoptosis, and morphological changes in hippocampal neurons cultured in vitro, as well as the effects of calcium channels on neuronal apoptosis. The chloride channel blockers 4-acetamido-4'-isothiocyanatostilbene-2, 2'-disulfonic acid (SITS) or 4, 4'-diisethiocyanostilbene-2, 2'-disulfonic acid (DIDS) increased the survival rate of 3-morpholinosydnonimine (SIN-1)-treated neurons and suppressed SIN-l-induced neuronal apoptosis. The calcium channel blocker CdCI2 did not increase the survival rate of neurons and did not affect SIN-l-induced apoptosis or SITS- or DIDS-suppressed neuronal apoptosis. Results demonstrated that calcium channels did not significantly affect neuronal apoptosis.