Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CF...Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CFTRinh-172 or forskolin (FSK) in this study were used to treat human sperm separately, and the rates of sperm autophagy and progressive motility, mitochondrial membrane potential (MMP) and ATP concentration, and the expression levels of related factors were detected to explore their relationship. It was showed that sperms treated with CFTRinh-172 or FSK reduced the levels of cAMP, CFTR and PKA, but increased sperm autophagy rate, expression levels of AMPK and LC3B. However, reactive oxygen species content had no significant difference. It was indicated that low level of CFTR performed with cAMP and its downstream effectors such as PKA and AMPK to regulate mitochondrial structure and function, leading to increased autophagy rate and reduced vitality of sperm.展开更多
AIM: To investigate the effect of tetramethylpyrazine (TMP), an active compound from Ligustium Wollichii Franchat, on electrolyte transport across the distal colon of rodents and the mechanism involved.METHODS: Th...AIM: To investigate the effect of tetramethylpyrazine (TMP), an active compound from Ligustium Wollichii Franchat, on electrolyte transport across the distal colon of rodents and the mechanism involved.METHODS: The short-circuit current (Isc) technique in conjunction with pharmacological agents and specific inhibitors were used in analyzing the electrolyte transport across the distal colon of rodents. The underlying cellular signaling mechanism was investigated by radioimmunoassay analysis (RIA) and a special mouse model of cystic fibrosis.RESULTS: IMP stimulated a conoentration-dependent rise in ISCl, which was dependent on both Cl^- and HCO3^-, and inhibited by apical application of diphenylamine-2,2'-dicarboxylic acid (DPC) and glibenclamide, but resistant to 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid disodium salt hydrate (DIDS). Removal of Na^+ from basolateral solution almost completely abolished the Isc response to TMP, but it was insensitive to apical Na^+ replacement or apical Na^+ channel blocker, amiloride. Pretreatment of colonic mucosa with BAPTA-AM, a membrane-permeable selective Ca2+ chelator, did not significantly alter the TMP-induced Iso No additive effect of forskolin and 3-isobutyl-l-methylxanthine ([BMX) was observed on the TMP-induced Isc, but it was significantly reduced by a protein kinase A inhibitor, H89.RIA results showed that TMP (1 mmol/L) elicited a significant increase in cellular cAMP production, which was similar to that elicited by the adenylate cyclase activator, forskolin (10μmol/L). The TMP-elicited Isc as well as forskolin- or IBMX-induced Isc were abolished in mice with homozygous mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) presenting defective CFTR functions and secretions.CONCLUSION: TMP may stimulate cAMP-dependent and CFTR-mediated Cl^- and HCO3^- secretion. This may have implications in the future development of alternative treatment for constipation.展开更多
Dysfunction of the cystic fibrosis transmembrane con-ductance regulator(CFTR) chloride channel causes cys-tic fibrosis, while inappropriate activity of this channeloccurs in secretory diarrhea and polycystic kidney di...Dysfunction of the cystic fibrosis transmembrane con-ductance regulator(CFTR) chloride channel causes cys-tic fibrosis, while inappropriate activity of this channeloccurs in secretory diarrhea and polycystic kidney dis-ease. Drugs that interact directly with CFTR are there-fore of interest in the treatment of a number of diseasestates. This review focuses on one class of small mol-ecules that interacts directly with CFTR, namely inhibi-tors that act by directly blocking chloride movementthrough the open channel pore. In theory such com-pounds could be of use in the treatment of diarrheaand polycystic kidney disease, however in practice allknown substances acting by this mechanism to inhibitCFTR function lack either the potency or specificity forin vivo use. Nevertheless, this theoretical pharmaco-logical usefulness set the scene for the developmentof more potent, specific CFTR inhibitors. Biophysically,open channel blockers have proven most useful as ex-perimental probes of the structure and function of theCFTR chloride channel pore. Most importantly, the useof these blockers has been fundamental in developing afunctional model of the pore that includes a wide innervestibule that uses positively charged amino acid sidechains to attract both permeant and blocking anionsfrom the cell cytoplasm. CFTR channels are also subjectto this kind of blocking action by endogenous anionspresent in the cell cytoplasm, and recently this blocking effect has been suggested to play a role in the physio-logical control of CFTR channel function, in particular as a novel mechanism linking CFTR function dynamically to the composition of epithelial cell secretions. It has also been suggested that future drugs could target this same pathway as a way of pharmacologically increasing CFTR activity in cystic fibrosis. Studying open channel blockers and their mechanisms of action has resulted in significant advances in our understanding of CFTR as a pharmacological target in disease states, of CFTR chan-nel structure and function, and of how CFTR activity is controlled by its local environment.展开更多
Cystic fibrosis transmembrane conductance regulator(CFTR), a glycoprotein with 1480 amino acids, has been well established as a chloride channel mainly expressed in the epithelial cells of various tissues and organs s...Cystic fibrosis transmembrane conductance regulator(CFTR), a glycoprotein with 1480 amino acids, has been well established as a chloride channel mainly expressed in the epithelial cells of various tissues and organs such as lungs, sweat glands, gastrointestinal system, and reproductive organs. Although defective CFTR leads to cystic fibrosis, a common genetic disorder in the Caucasian population, there is accumulating evidence that suggests a novel role of CFTR in various cancers, especially in gastroenterological cancers, such as pancreatic cancer and colon cancer. In this review, we summarize the emerging findings that link CFTR with various cancers, with focus on the association between CFTR defects and gastrointestinal cancers as well as the underlying mechanisms. Further study of CFTR in cancer biology may help pave a new way for the diagnosis and treatment of gastrointestinal cancers.展开更多
BACKGROUND Intestinal ischemia/reperfusion(I/R)injury is a fatal syndrome that occurs under many clinical scenarios.The apoptosis of intestinal cells caused by ischemia can cause cell damage and provoke systemic dysfu...BACKGROUND Intestinal ischemia/reperfusion(I/R)injury is a fatal syndrome that occurs under many clinical scenarios.The apoptosis of intestinal cells caused by ischemia can cause cell damage and provoke systemic dysfunction during reperfusion.However,the mechanism of I/R-induced apoptosis remains unclear.Cystic fibrosis transmembrane conductance regulator(CFTR)is a cAMP-activated chloride channel.Few researchers have paid attention to its role in intestinal I/R injury,or the relationship between CFTR and intestinal apoptosis induced by hypoxia/reoxygenation(H/R).AIM To investigate the effects of CFTR on I/R-induced intestinal apoptosis and its underlying molecular mechanisms.METHODS An intestinal I/R injury model was established in mice with superior mesenteric artery occlusion, and Caco2 cells were subjected to H/R for the simulation of I/R in vivo.RESULTSThe results suggested that CFTR overexpression significantly increased the Caco2 cell viability anddecreased cell apoptosis induced by the H/R. Interestingly, we found that the translocation of p65,an NF-κB member, from the cytoplasm to the nucleus after H/R treatment can be reversed by theoverexpression of CFTR, the NF-κB P65 would return from the nucleus to the cytoplasm asdetermined by immunostaining. We also discovered that CFTR inhibited cell apoptosis in theH/R-treated cells, and this effect was significantly curbed by the NF-κB activator BA, AKTinhibitor GSK690693 and the PI3K inhibitor LY294002. Moreover, we demonstrated that CFTRoverexpression could reverse the decreased PI3K/AKT expression induced by the I/R treatment invivo or H/R treatment in vitro.CONCLUSIONThe results of the present study indicate that the overexpression of CFTR protects Caco2 cells fromH/R-induced apoptosis;furthermore, it also inhibits H/R-induced apoptosis through thePI3K/AKT/NF-κB signaling pathway in H/R-treated Caco2 cells and intestinal tissues.展开更多
BACKGROUND Acute recurrent pancreatitis(ARP)is characterized by episodes of acute pancreatitis in an otherwise normal gland.When no cause of ARP is identifiable,the diagnosis of"idiopathic"ARP is given.Mutat...BACKGROUND Acute recurrent pancreatitis(ARP)is characterized by episodes of acute pancreatitis in an otherwise normal gland.When no cause of ARP is identifiable,the diagnosis of"idiopathic"ARP is given.Mutations in the cystic fibrosis transmembrane conductance regulator(CFTR)gene increase the risk of ARP by 3-to 4-times compared to the general population,while cystic fibrosis(CF)patients present with a 40-to 80-times higher risk of developing pancreatitis.CASE SUMMARY In non-classical CF or CFTR-related disorders,CFTR functional tests can help to ensure a proper diagnosis.We applied an individualized combination of standardized and new CFTR functional bioassays for a patient referred to the Verona CF Center for evaluation after several episodes of acute pancreatitis.The CFTR genotype was G542X+/-with IVS8Tn:T7/9 polymorphism.The sweat(Cl-)values were borderline.Intestinal current measurements were performed according to the European Cystic Fibrosis Society Standardized Operating Procedure.Recent nasal surgery for deviated septum did not allow for nasal potential difference measurements.Lung function and sputum cultures were normal;azoospermia was excluded.Pancreas divisum was excluded by imaging but hypoplasia of the left hepatic lobe was detected.Innovative tests applied in this case include sweat rate measurement by image analysis,CFTR function in monocytes evaluated using a membrane potential-sensitive fluorescent probe,and the intestinal organoids forskolin-induced swelling assay.CONCLUSION Combination of innovative CFTR functional assays might support a controversial diagnosis when CFTR-related disorders and/or non-classical CF are suspected.展开更多
The protein expression of cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl- channel, in ovarian stimulated premature female rat ovary during a cycle of follicle development and corpus ...The protein expression of cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl- channel, in ovarian stimulated premature female rat ovary during a cycle of follicle development and corpus luteum formation was investigated. Animals were injected with 10 U pregnant Mare's serum gonadotropin (PMSG) and subsequently 10 U hCG 48 h later. Time-dependent immunohistochemistry and Western blotting experiments were performed before and 24, 48, 72 h after hCG treatment. The immunohistochemistry revealed that administration of PMSG stimulated the CFTR expression in thecal cell layer and granulosa cell layer of mature follicles 48 h post injection, coincident with the PMSG-induced peak in follicular estradiol. However, the expression of CFTR in the granulose lutein cell layer and thecal lutein cell layer was time-dependently reduced following hCG injection, in accordance with the gradually increased progestogen level during luteum corpus formation. Western blotting analysis demonstrated that rat ovarian tissue expressed the special CFTR band at 170 kD. It is concluded that cAMP-dependent Cl- channels are involved in regulation of follicle development and luteum formation.展开更多
Cystic fibrosis, a common autosomal recessive genetic disorder among Caucasians, is caused by defects in the transmembrane conductance regulatory(CFTR) gene. The analysis of CFTR gene mutations is useful to better cha...Cystic fibrosis, a common autosomal recessive genetic disorder among Caucasians, is caused by defects in the transmembrane conductance regulatory(CFTR) gene. The analysis of CFTR gene mutations is useful to better characterize the disease, and for preconceptional screening, prenatal and preimplantation genetic diagnosis. Here we report the results of a genetic analysis in a 16-year-old boy from southwestern Iran diagnosed as having cystic fibrosis in infancy based on gastrointestinal and pulmonary manifestations, with positive sweat chloride tests. He lacked both normal and mutant forms of the fragment corresponding to the F508 allele in initial genetic studies. Multiplex ligationdependent probe amplification-based testing revealed a homozygous deletion spanning exons 4 to 10 of the CFTR gene. We predict an in-frame deletion removing 373 amino acids based on our sequencing results. Determining CFTR gene mutations in patients and their family members would be helpful to prevent the occurrence of new cases, especially in populations in which consanguinity is common.展开更多
BACKGROUND Cystic fibrosis(CF)is rare in Asian populations relative to the Caucasian population.In this paper,we report the cystic fibrosis transmembrane conductance regulator(CFTR)variation in a family of Chinese CF ...BACKGROUND Cystic fibrosis(CF)is rare in Asian populations relative to the Caucasian population.In this paper,we report the cystic fibrosis transmembrane conductance regulator(CFTR)variation in a family of Chinese CF patients,and systematically review the previous literature.CASE SUMMARY Here we report a 30-month-old Chinese girl who was diagnosed with CF based on her history and symptoms such as recurrent productive cough,wheezing with repeated infection of Pseudomonas aeruginosa,and parasinusitis.Chest computed tomography(CT)scanning revealed obvious exudative lesions and bilateral bronchiectasis.Liver CT scanning revealed a low-density lesion in the left lobe of the liver.A diagnosis of CF was made based upon CFTR gene tests.The CFTR gene was sequenced using the blood samples of her and her parents and showed a heterozygous novel missense mutation of c.753_754delAG in exon 7.In addition,a heterozygous c.1240 C>T mutation was found in exon 10 of the CFTR.The mutation c.753_754delAG was verified to have been inherited from her mother,and the c.1240 C>T mutation was from her father who was diagnosed with congenital absence of vas deferens.CONCLUSION A novel mutation of CFTR,c.753_754delAG,was found in a Chinese CF child.c.2909G>A is the most common mutation among Chinese CF patients.展开更多
Cystic fibrosis(CF)is an autosomal recessive disorder caused by mutations in the CF transmembrane conductance regulator gene.CF liver disease develops in 5%-10%of patients with CF and is the third leading cause of dea...Cystic fibrosis(CF)is an autosomal recessive disorder caused by mutations in the CF transmembrane conductance regulator gene.CF liver disease develops in 5%-10%of patients with CF and is the third leading cause of death among patients with CF after pulmonary disease or lung transplant complications.We review the pathogenesis,clinical presentations,complications,diagnostic evaluation,effect of medical therapies especially CF transmembrane conductance regulator modulators and liver transplantation in CF associated liver disease.展开更多
BACKGROUND Hepatic steatosis is a common form of cystic fibrosis associated liver disease(CFLD)seen in an estimated 15%-60%of patients with cystic fibrosis(CF).The pathophysiology and health implications of hepatic st...BACKGROUND Hepatic steatosis is a common form of cystic fibrosis associated liver disease(CFLD)seen in an estimated 15%-60%of patients with cystic fibrosis(CF).The pathophysiology and health implications of hepatic steatosis in cystic fibrosis remain largely unknown.In the general population,hepatic steatosis is strongly associated with insulin resistance and type 2 diabetes.Cystic fibrosis related diabetes(CFRD)impacts 40%-50%of CF adults and is characterized by both insulin insufficiency and insulin resistance.We hypothesized that patients with CFRD would have higher levels of hepatic steatosis than cystic fibrosis patients without diabetes.AIM To determine whether CFRD is associated with hepatic steatosis and to explore the impact of lumacaftor/ivacaftor therapy on hepatic steatosis in CF.METHODS Thirty patients with CF were recruited from a tertiary care medical center for this cross-sectional study.Only pancreatic insufficient patients with CFRD or normal glucose tolerance(NGT)were included.Patients with established CFLD,end stage lung disease,or persistently elevated liver enzymes were excluded.Mean magnetic resonance imaging(MRI)proton density fat fraction(PDFF)was obtained for all participants.Clinical characteristics[age,sex,body mass index,percent predicted forced expiratory volume at 1 s(FEV1),lumacaftor/ivacaftor use]and blood chemistries were assessed for possible association with hepatic steatosis.Hepatic steatosis was defined as a mean MRI PDFF>5%.Patients were grouped by diabetes status(CFRD,NGT)and cystic fibrosis transmembrane conductance regulator(CFTR)modulator use(lumacaftor/ivacaftor,no lumacaftor/ivacaftor)to determine between group differences.Continuous variables were analyzed with a Wilcoxon rank sum test and discrete variables with a Chi square test or Fisher’s exact test.RESULTS Twenty subjects were included in the final analysis.The median age was 22.3 years(11.3-39.0)and median FEV1 was 77%(33%-105%).Twelve subjects had CFRD and 8 had NGT.Nine subjects were receiving lumacaftor/ivacaftor.The median PDFF was 3.0%(0.0%-21.0%).Six subjects(30%)had hepatic steatosis defined as PDFF>5%.Hepatic fat fraction was significantly lower in patients receiving lumacaftor/ivacaftor(median,range)(2.0%,0.0%-6.4%)than in patients not receiving lumacaftor/ivacaftor(4.1%,2.7-21.0%),P=0.002.Though patients with CFRD had lower PDFF(2.2%,0.0%-14.5%)than patients with NGT(4.9%,2.4-21.0%)this did not reach statistical significance,P=0.06.No other clinical characteristic was strongly associated with hepatic steatosis.CONCLUSION Use of the CFTR modulator lumacaftor/ivacaftor was associated with significantly lower hepatic steatosis.No association between CFRD and hepatic steatosis was found in this cohort.展开更多
The effects and the mechanisms of natural compounds ginkgolides on CFTR-mediate anion transport were investigated. The CFTR-mediate iodide influx rates were studied via a cell-based fluorescence assay done for FRT cel...The effects and the mechanisms of natural compounds ginkgolides on CFTR-mediate anion transport were investigated. The CFTR-mediate iodide influx rates were studied via a cell-based fluorescence assay done for FRT cells stably transfected by CFTR; transepithelial short-circuit current recordings of FRT cells and rat distal colon mucosa were respectively obtained. Cellular cAMP concentrations were measured via a radioimmunoassay analysis kit. Ginkgolide C dose-dependently increases CFTR-mediate anion transport, whereas ginkgolide A and B show no effect. The activation is sensitive to CFTR specific activator CFTRinh-172. Ginkgolide C stimulated amiloride and indomethacin pre-treated Cl currents in rat distal colon mucosa. Studies on FRT cells also manifest that ginkgolide C had additive effect with FSK/IBMX mixture and didn't elevate intracellular cAMP concentration, which implies it works through a direct binding mechanism. In conclusion, Ginkgolide C directly stimulates CFTR-mediate anion transport. Ginkgolide C may be a promising drug for the prevention and treatment of CFTR-related diseases such as idiopathic chronic pancreatitis(ICP), habitual constipation, and kcratoconjunctivitis sicca(KCS).展开更多
Cystic fibrosis(CF)is a common autosomal recessive disease.Life expectancy of patients with CF continues to improve mainly driven by the evolving therapies for CF-related organ dysfunction.The prevalence of CF-related...Cystic fibrosis(CF)is a common autosomal recessive disease.Life expectancy of patients with CF continues to improve mainly driven by the evolving therapies for CF-related organ dysfunction.The prevalence of CF-related diabetes(CFRD)increases exponentially as patients’age.Clinical care guidelines for CFRD from 2010,recommend insulin as the mainstay of treatment.Many patients with CFRD may not require exogenous insulin due to the heterogeneity of this clinical entity.Maintenance of euglycemia by enhancing endogenous insulin production,secretion and degradation with novel pharmacological therapies like glucagonlike peptide-1 agonist is an option that remains to be fully explored.As such,the scope of this article will focus on our perspective of glucagon-like peptide-1 receptor agonist in the context of CFRD.Other potential options such as sodiumglucose cotransporter-2 and dipeptidyl peptidase 4 inhibitors and their impact on this patient population is limited and further studies are required.展开更多
Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have been implicated in the onset of cystic fibrosis and other clinical respiratory disorders. In the present study, we investigated t...Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have been implicated in the onset of cystic fibrosis and other clinical respiratory disorders. In the present study, we investigated the role of CFTR variations, poly-T, TG-repeats, and M470V in susceptibility to bronchial asthma and chronic bronchitis in a Chinese population in Jiangsu province, China. A total of 72 bronchial asthma patients, 68 chronic bronchitis pa- tients, and 117 healthy subjects were included in this study. The Tn-TGm haplotype was sequenced and the CFTR variant M470V was detected using restriction fragment length polymorphism (RFLP). We found that the fre- quency of TS-TG12-V470 in chronic bronchitis patients was 0.07%, which was notably higher than that in healthy subjects (0.01%) and bronchial asthma patients (0.04%). Thus, the presence of the TS-TG12 haplotype of the CFTR gene is likely to play a role in the development and progression of respiratory conditions, such as chronic bronchitis.展开更多
The case of a 32-year-old black woman of African descent who suffered from repeated episodes of acute pancreatitis, initially triggered when flying on airplanes, is reported. She did not drink alcohol or smoke. Geneti...The case of a 32-year-old black woman of African descent who suffered from repeated episodes of acute pancreatitis, initially triggered when flying on airplanes, is reported. She did not drink alcohol or smoke. Genetic analysis was negative for cationic trypsinogen, serine protease inhibitor Kazal type 1 and chymotrypsin C. However, hemoglobin F was elevated. Sequencing of the thalassemia gene revealed a novel alteration in the 5' region indicative of a functional abnormality of the molecule. Sequencing the cystic fibrosis transmembrane conductance regulator(CFTR) gene revealed a heterozygote sequence variant. The combination of a hemoglobin gene mutation known for thalassemia in conjunction with the hitherto undescribed CFTR mutation is suggested to pave the road for initial and repetitive pancreatitis attacks. This will be discussed.展开更多
目的:探讨先天性单侧输精管缺如(CUAVD)合并无精子症患者囊性纤维化跨膜转导(CFTR)基因全外显子检测的结果与意义。方法:抽取CUAVD合并无精子症6例患者外周血行CFTR全外显子突变及多态性检测,测序结果与UCSC Genome Browser on Human De...目的:探讨先天性单侧输精管缺如(CUAVD)合并无精子症患者囊性纤维化跨膜转导(CFTR)基因全外显子检测的结果与意义。方法:抽取CUAVD合并无精子症6例患者外周血行CFTR全外显子突变及多态性检测,测序结果与UCSC Genome Browser on Human Dec.2013 Assembly进行在线比对及分析。结果:6例CUAVD合并无精子症患者中,1例第6号外显子中可检测到1个已知错义突变c.592G>C,2例患者第10号外显子前非编码区域发现c.1210-12T[5]剪切突变,且该2例患者合并第11号外显子上V470单倍体。结论:CUAVD合并无精子症患者CFTR全外显子基因突变有一定的检出率,有必要对这部分患者进行CFTR基因突变检测。展开更多
文摘Low sperm motility is one of the main causes of male infertility. Cystic fibrosis transmembrane conductance regulator (CFTR, an anion channel protein) is related to the progressive motility of sperm. CFTR disruptor CFTRinh-172 or forskolin (FSK) in this study were used to treat human sperm separately, and the rates of sperm autophagy and progressive motility, mitochondrial membrane potential (MMP) and ATP concentration, and the expression levels of related factors were detected to explore their relationship. It was showed that sperms treated with CFTRinh-172 or FSK reduced the levels of cAMP, CFTR and PKA, but increased sperm autophagy rate, expression levels of AMPK and LC3B. However, reactive oxygen species content had no significant difference. It was indicated that low level of CFTR performed with cAMP and its downstream effectors such as PKA and AMPK to regulate mitochondrial structure and function, leading to increased autophagy rate and reduced vitality of sperm.
基金Supported by the Innovation and Technology Fund of Hong Kong, China
文摘AIM: To investigate the effect of tetramethylpyrazine (TMP), an active compound from Ligustium Wollichii Franchat, on electrolyte transport across the distal colon of rodents and the mechanism involved.METHODS: The short-circuit current (Isc) technique in conjunction with pharmacological agents and specific inhibitors were used in analyzing the electrolyte transport across the distal colon of rodents. The underlying cellular signaling mechanism was investigated by radioimmunoassay analysis (RIA) and a special mouse model of cystic fibrosis.RESULTS: IMP stimulated a conoentration-dependent rise in ISCl, which was dependent on both Cl^- and HCO3^-, and inhibited by apical application of diphenylamine-2,2'-dicarboxylic acid (DPC) and glibenclamide, but resistant to 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid disodium salt hydrate (DIDS). Removal of Na^+ from basolateral solution almost completely abolished the Isc response to TMP, but it was insensitive to apical Na^+ replacement or apical Na^+ channel blocker, amiloride. Pretreatment of colonic mucosa with BAPTA-AM, a membrane-permeable selective Ca2+ chelator, did not significantly alter the TMP-induced Iso No additive effect of forskolin and 3-isobutyl-l-methylxanthine ([BMX) was observed on the TMP-induced Isc, but it was significantly reduced by a protein kinase A inhibitor, H89.RIA results showed that TMP (1 mmol/L) elicited a significant increase in cellular cAMP production, which was similar to that elicited by the adenylate cyclase activator, forskolin (10μmol/L). The TMP-elicited Isc as well as forskolin- or IBMX-induced Isc were abolished in mice with homozygous mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) presenting defective CFTR functions and secretions.CONCLUSION: TMP may stimulate cAMP-dependent and CFTR-mediated Cl^- and HCO3^- secretion. This may have implications in the future development of alternative treatment for constipation.
文摘Dysfunction of the cystic fibrosis transmembrane con-ductance regulator(CFTR) chloride channel causes cys-tic fibrosis, while inappropriate activity of this channeloccurs in secretory diarrhea and polycystic kidney dis-ease. Drugs that interact directly with CFTR are there-fore of interest in the treatment of a number of diseasestates. This review focuses on one class of small mol-ecules that interacts directly with CFTR, namely inhibi-tors that act by directly blocking chloride movementthrough the open channel pore. In theory such com-pounds could be of use in the treatment of diarrheaand polycystic kidney disease, however in practice allknown substances acting by this mechanism to inhibitCFTR function lack either the potency or specificity forin vivo use. Nevertheless, this theoretical pharmaco-logical usefulness set the scene for the developmentof more potent, specific CFTR inhibitors. Biophysically,open channel blockers have proven most useful as ex-perimental probes of the structure and function of theCFTR chloride channel pore. Most importantly, the useof these blockers has been fundamental in developing afunctional model of the pore that includes a wide innervestibule that uses positively charged amino acid sidechains to attract both permeant and blocking anionsfrom the cell cytoplasm. CFTR channels are also subjectto this kind of blocking action by endogenous anionspresent in the cell cytoplasm, and recently this blocking effect has been suggested to play a role in the physio-logical control of CFTR channel function, in particular as a novel mechanism linking CFTR function dynamically to the composition of epithelial cell secretions. It has also been suggested that future drugs could target this same pathway as a way of pharmacologically increasing CFTR activity in cystic fibrosis. Studying open channel blockers and their mechanisms of action has resulted in significant advances in our understanding of CFTR as a pharmacological target in disease states, of CFTR chan-nel structure and function, and of how CFTR activity is controlled by its local environment.
基金Supported by American Cancer Society Institutional Research to Li C,No.11-053-01-IRGNational Institutes of Health grant HL128647
文摘Cystic fibrosis transmembrane conductance regulator(CFTR), a glycoprotein with 1480 amino acids, has been well established as a chloride channel mainly expressed in the epithelial cells of various tissues and organs such as lungs, sweat glands, gastrointestinal system, and reproductive organs. Although defective CFTR leads to cystic fibrosis, a common genetic disorder in the Caucasian population, there is accumulating evidence that suggests a novel role of CFTR in various cancers, especially in gastroenterological cancers, such as pancreatic cancer and colon cancer. In this review, we summarize the emerging findings that link CFTR with various cancers, with focus on the association between CFTR defects and gastrointestinal cancers as well as the underlying mechanisms. Further study of CFTR in cancer biology may help pave a new way for the diagnosis and treatment of gastrointestinal cancers.
基金Supported by National Natural Science Foundation of China, No.81800473"Young Eagle Project"of Air Force Medical University, No.KT2021DX007
文摘BACKGROUND Intestinal ischemia/reperfusion(I/R)injury is a fatal syndrome that occurs under many clinical scenarios.The apoptosis of intestinal cells caused by ischemia can cause cell damage and provoke systemic dysfunction during reperfusion.However,the mechanism of I/R-induced apoptosis remains unclear.Cystic fibrosis transmembrane conductance regulator(CFTR)is a cAMP-activated chloride channel.Few researchers have paid attention to its role in intestinal I/R injury,or the relationship between CFTR and intestinal apoptosis induced by hypoxia/reoxygenation(H/R).AIM To investigate the effects of CFTR on I/R-induced intestinal apoptosis and its underlying molecular mechanisms.METHODS An intestinal I/R injury model was established in mice with superior mesenteric artery occlusion, and Caco2 cells were subjected to H/R for the simulation of I/R in vivo.RESULTSThe results suggested that CFTR overexpression significantly increased the Caco2 cell viability anddecreased cell apoptosis induced by the H/R. Interestingly, we found that the translocation of p65,an NF-κB member, from the cytoplasm to the nucleus after H/R treatment can be reversed by theoverexpression of CFTR, the NF-κB P65 would return from the nucleus to the cytoplasm asdetermined by immunostaining. We also discovered that CFTR inhibited cell apoptosis in theH/R-treated cells, and this effect was significantly curbed by the NF-κB activator BA, AKTinhibitor GSK690693 and the PI3K inhibitor LY294002. Moreover, we demonstrated that CFTRoverexpression could reverse the decreased PI3K/AKT expression induced by the I/R treatment invivo or H/R treatment in vitro.CONCLUSIONThe results of the present study indicate that the overexpression of CFTR protects Caco2 cells fromH/R-induced apoptosis;furthermore, it also inhibits H/R-induced apoptosis through thePI3K/AKT/NF-κB signaling pathway in H/R-treated Caco2 cells and intestinal tissues.
基金Supported by Italian CF Research Foundation with the contributions of Delegazione FFC di Palermo e di Vittoria Ragusa Catania 2,No.FFC grants No.4/2013Delegazione FFC di Treviso Montebelluna La Bottega delle Donne,No.3/2014+3 种基金Delegazione FFC di Belluno,No.7/2016Delegazione FFC di Taranto Massafra,Cosenza sud,della Valpolicella,Guadagnin SRL,No.6/2018Delegazione FFC di Tradate Gallarate,No.13/2018CFFT-USA and Lega Italiana Fibrosi Cistica-Associazione Veneta ONLUS
文摘BACKGROUND Acute recurrent pancreatitis(ARP)is characterized by episodes of acute pancreatitis in an otherwise normal gland.When no cause of ARP is identifiable,the diagnosis of"idiopathic"ARP is given.Mutations in the cystic fibrosis transmembrane conductance regulator(CFTR)gene increase the risk of ARP by 3-to 4-times compared to the general population,while cystic fibrosis(CF)patients present with a 40-to 80-times higher risk of developing pancreatitis.CASE SUMMARY In non-classical CF or CFTR-related disorders,CFTR functional tests can help to ensure a proper diagnosis.We applied an individualized combination of standardized and new CFTR functional bioassays for a patient referred to the Verona CF Center for evaluation after several episodes of acute pancreatitis.The CFTR genotype was G542X+/-with IVS8Tn:T7/9 polymorphism.The sweat(Cl-)values were borderline.Intestinal current measurements were performed according to the European Cystic Fibrosis Society Standardized Operating Procedure.Recent nasal surgery for deviated septum did not allow for nasal potential difference measurements.Lung function and sputum cultures were normal;azoospermia was excluded.Pancreas divisum was excluded by imaging but hypoplasia of the left hepatic lobe was detected.Innovative tests applied in this case include sweat rate measurement by image analysis,CFTR function in monocytes evaluated using a membrane potential-sensitive fluorescent probe,and the intestinal organoids forskolin-induced swelling assay.CONCLUSION Combination of innovative CFTR functional assays might support a controversial diagnosis when CFTR-related disorders and/or non-classical CF are suspected.
文摘The protein expression of cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated Cl- channel, in ovarian stimulated premature female rat ovary during a cycle of follicle development and corpus luteum formation was investigated. Animals were injected with 10 U pregnant Mare's serum gonadotropin (PMSG) and subsequently 10 U hCG 48 h later. Time-dependent immunohistochemistry and Western blotting experiments were performed before and 24, 48, 72 h after hCG treatment. The immunohistochemistry revealed that administration of PMSG stimulated the CFTR expression in thecal cell layer and granulosa cell layer of mature follicles 48 h post injection, coincident with the PMSG-induced peak in follicular estradiol. However, the expression of CFTR in the granulose lutein cell layer and thecal lutein cell layer was time-dependently reduced following hCG injection, in accordance with the gradually increased progestogen level during luteum corpus formation. Western blotting analysis demonstrated that rat ovarian tissue expressed the special CFTR band at 170 kD. It is concluded that cAMP-dependent Cl- channels are involved in regulation of follicle development and luteum formation.
基金Supported by Shiraz University of Medical Sciences,Shiraz,Iran and Bologna University,Bologna,Italy
文摘Cystic fibrosis, a common autosomal recessive genetic disorder among Caucasians, is caused by defects in the transmembrane conductance regulatory(CFTR) gene. The analysis of CFTR gene mutations is useful to better characterize the disease, and for preconceptional screening, prenatal and preimplantation genetic diagnosis. Here we report the results of a genetic analysis in a 16-year-old boy from southwestern Iran diagnosed as having cystic fibrosis in infancy based on gastrointestinal and pulmonary manifestations, with positive sweat chloride tests. He lacked both normal and mutant forms of the fragment corresponding to the F508 allele in initial genetic studies. Multiplex ligationdependent probe amplification-based testing revealed a homozygous deletion spanning exons 4 to 10 of the CFTR gene. We predict an in-frame deletion removing 373 amino acids based on our sequencing results. Determining CFTR gene mutations in patients and their family members would be helpful to prevent the occurrence of new cases, especially in populations in which consanguinity is common.
基金Supported by the National Natural Science Foundation of China,No.81573167Science and Technology Project of Jiangsu,No.BE2017657Livelihood Science and Technology Project of Suzhou,No.SYS201640
文摘BACKGROUND Cystic fibrosis(CF)is rare in Asian populations relative to the Caucasian population.In this paper,we report the cystic fibrosis transmembrane conductance regulator(CFTR)variation in a family of Chinese CF patients,and systematically review the previous literature.CASE SUMMARY Here we report a 30-month-old Chinese girl who was diagnosed with CF based on her history and symptoms such as recurrent productive cough,wheezing with repeated infection of Pseudomonas aeruginosa,and parasinusitis.Chest computed tomography(CT)scanning revealed obvious exudative lesions and bilateral bronchiectasis.Liver CT scanning revealed a low-density lesion in the left lobe of the liver.A diagnosis of CF was made based upon CFTR gene tests.The CFTR gene was sequenced using the blood samples of her and her parents and showed a heterozygous novel missense mutation of c.753_754delAG in exon 7.In addition,a heterozygous c.1240 C>T mutation was found in exon 10 of the CFTR.The mutation c.753_754delAG was verified to have been inherited from her mother,and the c.1240 C>T mutation was from her father who was diagnosed with congenital absence of vas deferens.CONCLUSION A novel mutation of CFTR,c.753_754delAG,was found in a Chinese CF child.c.2909G>A is the most common mutation among Chinese CF patients.
文摘Cystic fibrosis(CF)is an autosomal recessive disorder caused by mutations in the CF transmembrane conductance regulator gene.CF liver disease develops in 5%-10%of patients with CF and is the third leading cause of death among patients with CF after pulmonary disease or lung transplant complications.We review the pathogenesis,clinical presentations,complications,diagnostic evaluation,effect of medical therapies especially CF transmembrane conductance regulator modulators and liver transplantation in CF associated liver disease.
基金Supported by a grant from the University Hospitals Fellowship Research Award Program(FRAP)
文摘BACKGROUND Hepatic steatosis is a common form of cystic fibrosis associated liver disease(CFLD)seen in an estimated 15%-60%of patients with cystic fibrosis(CF).The pathophysiology and health implications of hepatic steatosis in cystic fibrosis remain largely unknown.In the general population,hepatic steatosis is strongly associated with insulin resistance and type 2 diabetes.Cystic fibrosis related diabetes(CFRD)impacts 40%-50%of CF adults and is characterized by both insulin insufficiency and insulin resistance.We hypothesized that patients with CFRD would have higher levels of hepatic steatosis than cystic fibrosis patients without diabetes.AIM To determine whether CFRD is associated with hepatic steatosis and to explore the impact of lumacaftor/ivacaftor therapy on hepatic steatosis in CF.METHODS Thirty patients with CF were recruited from a tertiary care medical center for this cross-sectional study.Only pancreatic insufficient patients with CFRD or normal glucose tolerance(NGT)were included.Patients with established CFLD,end stage lung disease,or persistently elevated liver enzymes were excluded.Mean magnetic resonance imaging(MRI)proton density fat fraction(PDFF)was obtained for all participants.Clinical characteristics[age,sex,body mass index,percent predicted forced expiratory volume at 1 s(FEV1),lumacaftor/ivacaftor use]and blood chemistries were assessed for possible association with hepatic steatosis.Hepatic steatosis was defined as a mean MRI PDFF>5%.Patients were grouped by diabetes status(CFRD,NGT)and cystic fibrosis transmembrane conductance regulator(CFTR)modulator use(lumacaftor/ivacaftor,no lumacaftor/ivacaftor)to determine between group differences.Continuous variables were analyzed with a Wilcoxon rank sum test and discrete variables with a Chi square test or Fisher’s exact test.RESULTS Twenty subjects were included in the final analysis.The median age was 22.3 years(11.3-39.0)and median FEV1 was 77%(33%-105%).Twelve subjects had CFRD and 8 had NGT.Nine subjects were receiving lumacaftor/ivacaftor.The median PDFF was 3.0%(0.0%-21.0%).Six subjects(30%)had hepatic steatosis defined as PDFF>5%.Hepatic fat fraction was significantly lower in patients receiving lumacaftor/ivacaftor(median,range)(2.0%,0.0%-6.4%)than in patients not receiving lumacaftor/ivacaftor(4.1%,2.7-21.0%),P=0.002.Though patients with CFRD had lower PDFF(2.2%,0.0%-14.5%)than patients with NGT(4.9%,2.4-21.0%)this did not reach statistical significance,P=0.06.No other clinical characteristic was strongly associated with hepatic steatosis.CONCLUSION Use of the CFTR modulator lumacaftor/ivacaftor was associated with significantly lower hepatic steatosis.No association between CFRD and hepatic steatosis was found in this cohort.
基金Supported by Changchun Municipal Science and Technology Fund(No.2008116)Science and Technology Fund of Jilin Province(No.20090464)
文摘The effects and the mechanisms of natural compounds ginkgolides on CFTR-mediate anion transport were investigated. The CFTR-mediate iodide influx rates were studied via a cell-based fluorescence assay done for FRT cells stably transfected by CFTR; transepithelial short-circuit current recordings of FRT cells and rat distal colon mucosa were respectively obtained. Cellular cAMP concentrations were measured via a radioimmunoassay analysis kit. Ginkgolide C dose-dependently increases CFTR-mediate anion transport, whereas ginkgolide A and B show no effect. The activation is sensitive to CFTR specific activator CFTRinh-172. Ginkgolide C stimulated amiloride and indomethacin pre-treated Cl currents in rat distal colon mucosa. Studies on FRT cells also manifest that ginkgolide C had additive effect with FSK/IBMX mixture and didn't elevate intracellular cAMP concentration, which implies it works through a direct binding mechanism. In conclusion, Ginkgolide C directly stimulates CFTR-mediate anion transport. Ginkgolide C may be a promising drug for the prevention and treatment of CFTR-related diseases such as idiopathic chronic pancreatitis(ICP), habitual constipation, and kcratoconjunctivitis sicca(KCS).
文摘Cystic fibrosis(CF)is a common autosomal recessive disease.Life expectancy of patients with CF continues to improve mainly driven by the evolving therapies for CF-related organ dysfunction.The prevalence of CF-related diabetes(CFRD)increases exponentially as patients’age.Clinical care guidelines for CFRD from 2010,recommend insulin as the mainstay of treatment.Many patients with CFRD may not require exogenous insulin due to the heterogeneity of this clinical entity.Maintenance of euglycemia by enhancing endogenous insulin production,secretion and degradation with novel pharmacological therapies like glucagonlike peptide-1 agonist is an option that remains to be fully explored.As such,the scope of this article will focus on our perspective of glucagon-like peptide-1 receptor agonist in the context of CFRD.Other potential options such as sodiumglucose cotransporter-2 and dipeptidyl peptidase 4 inhibitors and their impact on this patient population is limited and further studies are required.
基金supported by the Key Talent's Subsidy Project in Science and Education of the Jiangsu Province (No. 2007158)
文摘Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have been implicated in the onset of cystic fibrosis and other clinical respiratory disorders. In the present study, we investigated the role of CFTR variations, poly-T, TG-repeats, and M470V in susceptibility to bronchial asthma and chronic bronchitis in a Chinese population in Jiangsu province, China. A total of 72 bronchial asthma patients, 68 chronic bronchitis pa- tients, and 117 healthy subjects were included in this study. The Tn-TGm haplotype was sequenced and the CFTR variant M470V was detected using restriction fragment length polymorphism (RFLP). We found that the fre- quency of TS-TG12-V470 in chronic bronchitis patients was 0.07%, which was notably higher than that in healthy subjects (0.01%) and bronchial asthma patients (0.04%). Thus, the presence of the TS-TG12 haplotype of the CFTR gene is likely to play a role in the development and progression of respiratory conditions, such as chronic bronchitis.
文摘The case of a 32-year-old black woman of African descent who suffered from repeated episodes of acute pancreatitis, initially triggered when flying on airplanes, is reported. She did not drink alcohol or smoke. Genetic analysis was negative for cationic trypsinogen, serine protease inhibitor Kazal type 1 and chymotrypsin C. However, hemoglobin F was elevated. Sequencing of the thalassemia gene revealed a novel alteration in the 5' region indicative of a functional abnormality of the molecule. Sequencing the cystic fibrosis transmembrane conductance regulator(CFTR) gene revealed a heterozygote sequence variant. The combination of a hemoglobin gene mutation known for thalassemia in conjunction with the hitherto undescribed CFTR mutation is suggested to pave the road for initial and repetitive pancreatitis attacks. This will be discussed.
文摘目的:探讨先天性单侧输精管缺如(CUAVD)合并无精子症患者囊性纤维化跨膜转导(CFTR)基因全外显子检测的结果与意义。方法:抽取CUAVD合并无精子症6例患者外周血行CFTR全外显子突变及多态性检测,测序结果与UCSC Genome Browser on Human Dec.2013 Assembly进行在线比对及分析。结果:6例CUAVD合并无精子症患者中,1例第6号外显子中可检测到1个已知错义突变c.592G>C,2例患者第10号外显子前非编码区域发现c.1210-12T[5]剪切突变,且该2例患者合并第11号外显子上V470单倍体。结论:CUAVD合并无精子症患者CFTR全外显子基因突变有一定的检出率,有必要对这部分患者进行CFTR基因突变检测。