Mucin secretion and PKC isoforms in SPOC1 goblet cells: differential activation by purinergic agonist and PMA

2003 ◽  
Vol 285 (1) ◽  
pp. L149-L160 ◽  
Author(s):  
Lubna H. Abdullah ◽  
Jason T. Bundy ◽  
Camille Ehre ◽  
C. William Davis

SPOC1 cells, which are a mucin-secreting model of rat airway goblet cells, possess a luminal P2Y2 purinoceptor through which UTP, ATP, and ATPγS stimulate secretion with EC50 values of ∼3 μM. PMA elicits mucin secretion with high EC50 (75 nM) and saturation (300 nM) values. For the first time in airway mucin-secreting cells, the PKC isoforms expressed and activated by a secretagogue were determined using RT-PCR/restriction-enzyme mapping and Western blotting. Five isoforms were expressed: cPKCα, nPKCδ and -η, and aPKCζ and -ι/λ. PMA caused cPKCα and nPKCδ to translocate to the membrane fraction of SPOC1 cells; only nPKCδ so responded to ATPγS. Membrane-associated nPKCδ and mucin secretion increased in parallel with ATPγS concentration and yielded EC50 values of 2–3 μM and maximum values of 100 μM. Effects of PMA to increase membrane-associated cPKCα and nPKCδ saturated at 30 nM, whereas mucin secretion saturated at 300 nM, which suggests a significant PKC-independent effect of PMA on mucin secretion. A prime alternate phorbol ester-receptor candidate is the C1-domain protein MUNC13. RT-PCR revealed the expression of ubiquitous (ub)MUNC13-2 and its binding partner, DOC2-γ. Hence, P2Y2 agonists activate nPKCδ in SPOC1 cells. PMA activates cPKCα and nPKCδ at high affinity and stimulates a lower affinity PKC-independent pathway that leads to mucin secretion.

2006 ◽  
Vol 290 (6) ◽  
pp. G1105-G1113 ◽  
Author(s):  
Sandra Zoghbi ◽  
Aurélien Trompette ◽  
Jean Claustre ◽  
Mahmoud El Homsi ◽  
Javier Garzón ◽  
...  

We have recently shown that β-casomorphin-7, a milk opioid peptide, strongly stimulates mucin secretion in the rat jejunum through a nervous pathway and opioid receptor activation. In this study, the hypothesis that β-casomorphin-7 may also act directly on intestinal goblet cells was investigated in vitro in rat and human intestinal mucin-producing cells (DHE and HT29-MTX) using quantitative and semiquantitative RT-PCR and ELISA. The presence of μ-opioid receptors was demonstrated in rat goblet cells in the upper half of the colonic crypt and in the two cell lines by immunohistochemistry and RT-PCR. In rat DHE cells, β-casomorphin-7 increased the expression of rat mucin (rMuc)2 and rMuc3 but not rMuc1, rMuc4, and rMuc5AC. This effect was time and dose dependent, with the maximum of increase in transcripts being noticed for a concentration of 10−4 M after 2 h of stimulation for rMuc2 (225% of controls) and 4 h of stimulation for rMuc3 (208% of controls). Mucin secretion was maximally increased after 8 h of stimulation. Interestingly, these effects were prevented by pretreatment of the cells with the μ-opioid antagonist cyprodime. In human HT29-MTX cells, β-casomorphin-7 (10−4 M) also increased MUC5AC mRNA levels (219% after 24 h of stimulation) and the secretion of this mucin (169% of controls). In conclusion, β-casomorphin-7 may contribute significantly to mucin production via a direct effect on intestinal goblet cells and the activation of μ-opioid receptors. Because intestinal mucins have a crucial mucosal protective function, dairy products containing β-casomorphin-7 may improve intestinal protection and could have dietary and health applications.


Vaccines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 282
Author(s):  
Juan David Ramírez ◽  
Marina Muñoz ◽  
Nathalia Ballesteros ◽  
Luz H. Patiño ◽  
Sergio Castañeda ◽  
...  

The continuing evolution of SARS-CoV-2 and the emergence of novel variants have raised concerns about possible reinfection events and potential changes in the coronavirus disease 2019 (COVID-19) transmission dynamics. Utilizing Oxford Nanopore technologies, we sequenced paired samples of three patients with positive RT-PCR results in a 1–2-month window period, and subsequent phylogenetics and genetic polymorphism analysis of these genomes was performed. Herein, we report, for the first time, genomic evidence of one case of reinfection in Colombia, exhibiting different SARS-CoV-2 lineage classifications between samples (B.1 and B.1.1.269). Furthermore, we report two cases of possible viral persistence, highlighting the importance of deepening our understanding on the evolutionary intra-host traits of this virus throughout different timeframes of disease progression. These results emphasize the relevance of genomic surveillance as a tool for understanding SARS-CoV-2 infection dynamics, and how this may translate effectively to future control and mitigations efforts, such as the national vaccination program.


2016 ◽  
Vol 144 (16) ◽  
pp. 3422-3425 ◽  
Author(s):  
P. SINGH ◽  
M. CHHABRA ◽  
P. SHARMA ◽  
R. JAISWAL ◽  
G. SINGH ◽  
...  

SUMMARYCrimean-Congo haemorrhagic fever (CCHF) is an emerging zoonotic disease in India which is prevalent in neighbouring countries. CCHF virus (CCHFV) is a widespread tick-borne virus which is endemic in Africa, Asia, Eastern Europe and the Middle East. In the present study, samples of clinically suspected human cases from different areas of northern-western India were tested for the presence of CCHFV by RT–PCR through amplification of nucleocapsid (N) gene of CCHFV. Positive samples were sequenced to reveal the prevailing CCHFV genotype(s) and phylogenetic relatedness. A phylogenetic tree revealed the emergence of diverse strains in the study region showing maximum identity with the Pakistan, Afghanistan and Iran strains, which was different from earlier reported Indian strains. Our findings reveal for the first time the emergence of the Asia 1 group in India; while earlier reported CCHFV strains belong to the Asia 2 group.


2005 ◽  
Vol 288 (1) ◽  
pp. C46-C56 ◽  
Author(s):  
Camille Ehre ◽  
Andrea H. Rossi ◽  
Lubna H. Abdullah ◽  
Kathleen De Pestel ◽  
Sandra Hill ◽  
...  

Airway goblet cells secrete mucin onto mucosal surfaces under the regulation of an apical, phospholipase C/Gq-coupled P2Y2receptor. We tested whether cortical actin filaments negatively regulate exocytosis in goblet cells by forming a barrier between secretory granules and plasma membrane docking sites as postulated for other secretory cells. Immunostaining of human lung tissues and SPOC1 cells (an epithelial, mucin-secreting cell line) revealed an apical distribution of β- and γ-actin in ciliated and goblet cells. In goblet cells, actin appeared as a prominent subplasmalemmal sheet lying between granules and the apical membrane, and it disappeared from SPOC1 cells activated by purinergic agonist. Disruption of actin filaments with latrunculin A stimulated SPOC1 cell mucin secretion under basal and agonist-activated conditions, whereas stabilization with jasplakinolide or overexpression of β- or γ-actin conjugated to yellow fluorescent protein (YFP) inhibited secretion. Myristoylated alanine-rich C kinase substrate, a PKC-activated actin-plasma membrane tethering protein, was phosphorylated after agonist stimulation, suggesting a translocation to the cytosol. Scinderin (or adseverin), a Ca2+-activated actin filament severing and capping protein was cloned from human airway and SPOC1 cells, and synthetic peptides corresponding to its actin-binding domains inhibited mucin secretion. We conclude that actin filaments negatively regulate mucin secretion basally in airway goblet cells and are dynamically remodeled in agonist-stimulated cells to promote exocytosis.


Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 674
Author(s):  
Anton Yuzhakov ◽  
Ksenia Yuzhakova ◽  
Nadezhda Kulikova ◽  
Lidia Kisteneva ◽  
Stanislav Cherepushkin ◽  
...  

Group A rotavirus (RVA) infection is the leading cause of hospitalization of children under 5 years old, presenting with symptoms of acute gastroenteritis. The aim of our study was to explore the genetic diversity of RVA among patients admitted to Moscow Infectious Disease Clinical Hospital No. 1 with symptoms of acute gastroenteritis. A total of 653 samples were collected from May 2019 through March 2020. Out of them, 135 (20.67%) fecal samples were found to be positive for rotavirus antigen by ELISA. RT-PCR detected rotavirus RNA in 80 samples. Seven G-genotypes (G1, G2, G3, G4, G8, G9, and G12) and three P-genotypes (P[8], P[4], and P[6]) formed 9 different combinations. The most common combination was G9P[8]. However, for the first time in Moscow, the combination G3P[8] took second place. Moreover, all detected viruses of this combination belonged to Equine-like G3P[8] viruses that had never been detected in Russia before. The genotype G8P[8] and G9P[4] rotaviruses were also detected in Moscow for the first time. Among the studied rotaviruses, there were equal proportions of Wa and DS-1-like strains; previous studies showed that Wa-like strains accounted for the largest proportion of rotaviruses in Russia.


2017 ◽  
Vol 11 (11) ◽  
pp. 854-860 ◽  
Author(s):  
Ahmed A Zaghawa ◽  
Fadhel Housawi ◽  
Abdulmohsen Al-Naeem ◽  
Ahmed Elsify ◽  
Yamen Mohammed Hegazy

Introduction: Bovine ephemeral fever virus (BEFV) is an arthropod borne Rhabdovirus affects cattle and water buffalo causes acute febrile disease. Methodology: The clinical picture and epidemiological pattern of BEF were described among cattle in epidemics of 2007, 2009 and 2011 in four geographical regions of Kingdom Saudi Arabia (Eastern, Jizan, Qasim, and Riyadh). Serum samples were tested using VNT. Virus isolation and molecular characterization were carried out for the first time in KSA. Results: The main clinical symptoms were fever, stiffness, lameness, salivation and subcutaneous emphysema. The prevalence and the mortality rate of BEF have decreased from 70% and 4.6% in 2007 to 30% and 0.6% in 2011, respectively in the 4 studied areas. There was no region association with higher prevalence of BEF. The intracluster correlation (ICC) was estimated for the first time in KSA as 0.0034. BEFV had been isolated from 11 out of 20 samples (55%) and isolation was confirmed by VNT. The molecular detection of BEFV by RT-PCR and real- time RT-qPCR were found more sensitive for diagnosis of the disease than virus isolation; 80% and 90% for the former tests and 55% for the latter. Three isolates were sequenced, they showed 84.7% - 100% identities in between and shared 90.4%-96.5% sequence identity with a previously published sequence from Australia (KF679404). The generated sequences belonged to 3rd cluster of BEFV glycoprotein. Conclusions: BEF occurrence has cyclic nature and the efficacy of vaccines prepared from local strains has to be evaluated and considered in diseases control.


2016 ◽  
Vol 68 (3) ◽  
pp. 641-649 ◽  
Author(s):  
Ivana Koledin ◽  
Renata Kovac ◽  
Vesna Rajkovic ◽  
Milica Matavulj

Acrylamide (AA) is an important industrial chemical worldwide. AA also forms naturally in many high-carbohydrate foods (bread, French fries, coffee, etc.) when they are heated. Since AA is ubiquitous in the human diet, and more than one-third of the calories we take in each day come from foods with detectable levels of acrylamide, the aim of this study was to determine the effect of subchronic AA treatment on colon goblet cell mucin secretion. Male Wistar rats were gavaged with AA for 5 days a week for 21 days. The animals were divided into three groups that were gavaged with different AA concentrations (0, 25, 50 mg/kg/day). Colon samples were processed for histochemical (PAS-AB, HID-AB) and immunohistochemical (anti-rat MUC2 antibody) staining to visualize mucins in the goblet cells. AA treatment showed an alteration in mucin production and secretion in that the amount of all investigated mucin types dropped. More prominent changes were detected in the upper crypt part where a decreased number of goblet cell was observed. AA treatment elicited a significant reduction in neutral mucins, while acidic mucins showed linearly decreasing trend with respect to AA doses. Also, a linear reduction of MUC2 mucins was noticed. Sulfomucins were absent in the colon lower crypt in all experimental groups, while in the upper crypt both sulfo- and sialomucins were significantly decreased. The results of our study point to changes in the synthesis, differentiation and distribution of mucins after AA treatment, which can have adverse effect on colorectal health.


Reproduction ◽  
2011 ◽  
Vol 142 (3) ◽  
pp. 467-476 ◽  
Author(s):  
C Mislanova ◽  
O Martsenyuk ◽  
B Huppertz ◽  
M Obolenskaya

The etiology and degree of clinical symptoms of preeclampsia depend on genotypic and phenotypic maternal and trophoblast factors, and elevated levels of plasma homocysteine (Hcy) are one of the pathogenetic factors of preeclampsia. To assess the impact of the folate-related metabolism, we characterized the indices of this metabolism in 40 samples from uncomplicated term placentas and 28 samples from preeclamptic pregnancies by quantifying the total content of folate, methionine (Met), Hcy and related cysteine, and glutathione (GSH) in compliance with the 677 C/T genotype of methylene tetrahydrofolate reductase (MTHFR). The prevalence ofMTHFRgenotypes was not significantly different between the two groups. The polymorphism ofMTHFRwas not unambiguously connected with the content of total placental Met, Hcy and related cysteine, and GSH either in uncomplicated or in complicated pregnancies. By contrast, the combination of the heterozygousMTHFRgenotype with folate deficiency in the samples from preeclamptic pregnancies was characterized by a statistically significant decrease in the Met content, a trend toward increased Hcy levels and a tight association between metabolically directly and indirectly related compounds, e.g. positive relation between Hcy versus cysteine and folate versus GSH and negative relation between folate versus Hcy and both Hcy and cysteine versus GSH. We demonstrated the expression of cystathionine-β-synthase (CBS) in human placenta at term by RT-PCR and western blot analysis, for the first time, and confirmed its catalytic activity and the accumulation of cysteine and CBS in placental explants cultivated in the presence of elevated Hcy concentrations. We suggest that disturbance in placental folate-related metabolism may be one of the pathogenetic factors in preeclampsia.


mBio ◽  
2016 ◽  
Vol 7 (2) ◽  
Author(s):  
Matthew J. Memoli ◽  
Pamela A. Shaw ◽  
Alison Han ◽  
Lindsay Czajkowski ◽  
Susan Reed ◽  
...  

ABSTRACTDespite long-term investment, influenza continues to be a significant worldwide problem. The cornerstone of protection remains vaccination, and approved vaccines seek to elicit a hemagglutination inhibition (HAI) titer of ≥1:40 as the primary correlate of protection. However, recent poor vaccine performance raises questions regarding the protection afforded and whether other correlates of protection should be targeted. A healthy volunteer challenge study was performed with a wild-type 2009 A(H1N1)pdm influenza A challenge virus at the NIH Clinical Center to evaluate two groups of participants with HAI titers of ≥1:40 and <1:40. The primary objective was to determine whether participants with HAI titers of ≥1:40 were less likely to develop mild to moderate influenza disease (MMID) after intranasal inoculation. HAI titers of ≥1:40 were protective against MMID but did not reduce the incidence of symptoms alone. Although the baseline HAI titer correlated with some reduction in disease severity measures, overall, the baseline NAI titer correlated more significantly with all disease severity metrics and had a stronger independent effect on outcome. This study demonstrates the importance of examining other immunological correlates of protection rather than solely HAI titers. This challenge study confirms the importance of NAI titer as a correlate and for the first time establishes that it can be an independent predictor of reduction of all aspects of influenza disease. This suggests that NAI titer may play a more significant role than previously thought and that neuraminidase immunity should be considered when studying susceptibility after vaccination and as a critical target in future influenza vaccine platforms.IMPORTANCEThis study represents the first time the current gold standard for evaluating influenza vaccines as set by the U.S. Food and Drug Administration and the European Medicines Agency Committee for Medicinal Products for Human Use, a “protective” hemagglutination inhibition (HAI) titer of ≥1:40, has been evaluated in a well-controlled healthy volunteer challenge study since the cutoff was established. We used our established wild-type influenza A healthy volunteer human challenge model to evaluate how well this antibody titer predicts a reduction in influenza virus-induced disease. We demonstrate that although higher HAI titer is predictive of some protection, there is stronger evidence to suggest that neuraminidase inhibition (NAI) titer is more predictive of protection and reduced disease. This is the first time NAI titer has been clearly identified in a controlled trial of this type to be an independent predictor of a reduction in all aspects of influenza.


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