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Mucosal cytokine network in inflammatory bowel disease  [cached]
Akira Andoh, Yuhki Yagi, Makoto Shioya, Atsushi Nishida, Tomoyuki Tsujikawa, Yoshihide Fujiyama
World Journal of Gastroenterology , 2008,
Abstract: Inflammatory bowel disease (IBD), ulcerative colitis (UC) and Crohn’s disease (CD) are characterized by ongoing mucosal inflammation in which dysfunction of the host immunologic response against dietary factors and commensal bacteria is involved. The chronic inflammatory process leads to disruption of the epithelial barrier, and the formation of epithelial ulceration. This permits easy access for the luminal microbiota and dietary antigens to cells resident in the lamina propria, and stimulates further pathological immune cell responses. Cytokines are essential mediators of the interactions between activated immune cells and non-immune cells, including epithelial and mesenchymal cells. The clinical efficacy of targeting TNF-α clearly indicates that cytokines are the therapeutic targets in IBD patients. In this manuscript, we focus on the biological activities of recently-reported cytokines [Interleukin (IL)-17 cytokine family, IL-31 and IL-32], which might play a role through interaction with TNF-α in the pathophysiology of IBD.
Immunohistochemical assessment of mucosal cytokine profile in acetic acid experimental colitis
Bertevello, Pedro L.;Logullo, ?ngela Flávia;Nonogaki, Sueli;Campos, Fabio M.;Chiferi, Valcir;Alves, Claudia C.;Torrinhas, Raquel S.;Gama-Rodrigues, Joaquim José;Waitzberg, Dan L.;
Clinics , 2005, DOI: 10.1590/S1807-59322005000400004
Abstract: experimental colitis induced by acetic acid has been used extensively as a model for intestinal inflammatory disease. colonic tissue lesions of intestinal inflammatory disease patients seem to be related to the increased local production of pro-inflammatory cytokines (il-1, il-6, tnf-a, and ifn-g). purpose: to assess the cytokine expression pattern identified through immunohistochemistry in colonic mucosa after experimental colitis induced by acetic acid and establish the relationship between this pattern and the presence of macroscopic lesions. materials and methods: adult male wistar rats (n = 39) were divided at random into 4 groups: nc45 and nc24 (control without colitis; sacrificed at 45 minutes and 24 hours, respectively); and wc45 and wc24 (with experimental colitis induced by acetic acid; sacrificed at 45 minutes and 24 hours, respectively). macroscopic and microscopic alterations in colonic tissue were evaluated, and cytokine expression was assessed through immunohistochemistry. results: after 24 hours, il-1 expression was greater in the groups with colitis when compared to the groups without colitis. il-4 expression was higher in the wc45 group. there was an increase in both inf-g and il-6 related to the presence of necrosis of the colonic mucosa in the groups with colitis for both periods evaluated. conclusion: the immunohistochemical technique was efficient for the analysis of various cytokine expressions in the colonic tissue. there was an increase in the il-1 pro-inflammatory cytokines as well as in il-6 and ifn-g associated with the presence of colonic necrosis. experimental colitis induced by acetic acid is a useful model for the development of studies assessing the role of cytokines in the inflammation of mucosa as well as anti-cytokine therapies.
Ribosomal Alteration-Derived Signals for Cytokine Induction in Mucosal and Systemic Inflammation: Noncanonical Pathways by Ribosomal Inactivation  [PDF]
Yuseok Moon
Mediators of Inflammation , 2014, DOI: 10.1155/2014/708193
Abstract: Ribosomal inactivation damages 28S ribosomal RNA by interfering with its functioning during gene translation, leading to stress responses linked to a variety of inflammatory disease processes. Although the primary effect of ribosomal inactivation in cells is the functional inhibition of global protein synthesis, early responsive gene products including proinflammatory cytokines are exclusively induced by toxic stress in highly dividing tissues such as lymphoid tissue and epithelia. In the present study, ribosomal inactivation-related modulation of cytokine production was reviewed in leukocyte and epithelial pathogenesis models to characterize mechanistic evidence of ribosome-derived cytokine induction and its implications for potent therapeutic targets of mucosal and systemic inflammatory illness, particularly those triggered by organellar dysfunctions. 1. Introduction As the functional organelle for protein synthesis, ribosomes bound to the endoplasmic reticulum (ER) perform complex surveillance of various pathologic stresses [1–3]. Ribosomal alteration by endogenous and external insults can trigger a variety of pathogenic processes, including inflammatory responses [4–6]. Ribosomal inactivation can be induced by a large family of ribonucleolytic proteins that cleave 28s ribosomal RNA at single phosphodiester bonds within a universally conserved sequence known as the sarcin-ricin loop, which leads to the dysfunction of peptidyltransferase and subsequent global translational arrest [7, 8]. These ribosome-inactivating proteins (RIPs) are enzymes isolated mostly from plants and some of RIPs such as ricins and shiga toxins are potent cytotoxic biological weapons causing tissue injuries and inflammatory diseases [9, 10]. Similar ribosomal RNA injuries have been observed during nonprotein ribosome-inactivating stress triggered by physical and chemical insults such as ultraviolet (UV) irradiation, trichothecene mycotoxins (mostly cereal contaminants produced by molds such Fusarium species), palytoxin (an intense vasoconstrictor produced by marine species including dinoflagellate Ostreopsis ovata), and anisomycin (an antibiotic produced by Streptomyces griseolus), which also interfere with peptidyltransferase activity by directly or indirectly modifying 28s rRNA [11, 12]. The primary action of most ribosome-inactivating stress is the functional inhibition of global protein synthesis; therefore, highly dividing tissues such as lymphoid tissue and mucosal epithelium are the most susceptible targets of the stress [13–15]. Although acute high levels of toxic
Role of Secreted Conjunctival Mucosal Cytokine and Chemokine Proteins in Different Stages of Trachomatous Disease  [PDF]
Troy A. Skwor,Berna Atik,Raj Prasad Kandel,Him Kant Adhikari,Bassant Sharma,Deborah Dean
PLOS Neglected Tropical Diseases , 2008, DOI: 10.1371/journal.pntd.0000264
Abstract: Background Chlamydia trachomatis is responsible for trachoma, the primary cause of preventable blindness worldwide. Plans to eradicate trachoma using the World Health Organization's SAFE program (Surgery, Antibiotics, Facial Cleanliness and Environment Improvement) have resulted in recurrence of infection and disease following cessation of treatment in many endemic countries, suggesting the need for a vaccine to control infection and trachomatous disease. Vaccine development requires, in part, knowledge of the mucosal host immune responses in both healthy and trachomatous conjuctivae—an area of research that remains insufficiently studied. Methodology/Principal Findings We characterized 25 secreted cytokines and chemokines from the conjunctival mucosa of individuals residing in a trachoma endemic region of Nepal using Luminex X100 multiplexing technology. Immunomodulating effects of concurrent C. trachomatis infection were also examined. We found that proinflammatory cytokines IL-1β (r = 0.259, P = 0.001) and TNFα (r = 0.168, P<0.05) were significantly associated with trachomatous disease and concurrent C. trachomatis infection compared with age and sex matched controls from the same region who did not have trachoma. In support of these findings, anti-inflammatory cytokine IL-1 receptor antagonist (IL-1Ra) was negatively associated with chronic scarring trachoma (r = ?0.249, P = 0.001). Additional cytokines (Th1, IL-12p40 [r = ?0.212, P<0.01], and Th2, IL-4 and IL-13 [r = ?0.165 and ?0.189, respectively, P<0.05 for both]) were negatively associated with chronic scarring trachoma, suggesting a protective role. Conversely, a pathogenic role for the Th3/Tr1 cytokine IL-10 (r = 0.180, P<0.05) was evident with increased levels for all trachoma grades. New risk factors for chronic scarring trachoma included IL-6 and IL-15 (r = 0.259 and 0.292, respectively, P<0.005 for both) with increased levels for concurrent C. trachomatis infections (r = 0.206, P<0.05, and r = 0.304, P<0.005, respectively). Chemokine protein levels for CCL11 (Eotaxin), CXCL8 (IL-8), CXCL9 (MIG), and CCL2 (MCP-1) were elevated in chronic scarring trachoma compared with age and sex matched controls (P<0.05, for all). Conclusions/Significance Our quantitative detection of previously uncharacterized and partially characterized cytokines, a soluble cytokine receptor, and chemokines for each trachoma grade and associations with C. trachomatis infections provide, to date, the most comprehensive immunologic evaluation of trachoma. These findings highlight novel pathologic and protective factors
Plant growth strategies are remodeled by spaceflight
Anna-Lisa Paul, Claire E Amalfitano, Robert J Ferl
BMC Plant Biology , 2012, DOI: 10.1186/1471-2229-12-232
Abstract: In the absence of gravity, but the presence of directional light, spaceflight roots remained strongly negatively phototropic and grew in the opposite direction of the shoot growth; however, cultivars WS and Col-0 displayed two distinct, marked differences in their growth patterns. First, cultivar WS skewed strongly to the right on orbit, while cultivar Col-0 grew with little deviation away from the light source. Second, the Spaceflight environment also impacted the rate of growth in Arabidopsis. The size of the Flight plants (as measured by primary root and hypocotyl length) was uniformly smaller than comparably aged Ground Control plants in both cultivars.Skewing and waving, thought to be gravity dependent phenomena, occur in spaceflight plants. In the presence of an orienting light source, phenotypic trends in skewing are gravity independent, and the general patterns of directional root growth typified by a given genotype in unit gravity are recapitulated on orbit, although overall growth patterns on orbit are less uniform. Skewing appears independent of axial orientation on the ISS – suggesting that other tropisms (such as for oxygen and temperature) do not influence skewing. An aspect of the spaceflight environment also retards the rate of early Arabidopsis growth.It is well known that plant growth patterns are influenced by a variety of stimuli and the responses to stimuli such as gravity have been explored and documented for over a century. In the past few decades it has been shown that the circumnutating “behavior” in plants, first described by Charles and Francis Darwin [1] and most recently revisited in [2] is primarily due to radially asymmetric growth in the elongating organs, which is in turn influenced by a variety of environmental stimuli (e.g. [3-7]). Of particular interest to us are the fundamental responses of plants to the unique environment of spaceflight, specifically the skewing and waving response of roots of Arabidopsis thaliana (Arabidopsis)
Spaceflight Promotes Biofilm Formation by Pseudomonas aeruginosa  [PDF]
Wooseong Kim, Farah K. Tengra, Zachary Young, Jasmine Shong, Nicholas Marchand, Hon Kit Chan, Ravindra C. Pangule, Macarena Parra, Jonathan S. Dordick, Joel L. Plawsky, Cynthia H. Collins
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0062437
Abstract: Understanding the effects of spaceflight on microbial communities is crucial for the success of long-term, manned space missions. Surface-associated bacterial communities, known as biofilms, were abundant on the Mir space station and continue to be a challenge on the International Space Station. The health and safety hazards linked to the development of biofilms are of particular concern due to the suppression of immune function observed during spaceflight. While planktonic cultures of microbes have indicated that spaceflight can lead to increases in growth and virulence, the effects of spaceflight on biofilm development and physiology remain unclear. To address this issue, Pseudomonas aeruginosa was cultured during two Space Shuttle Atlantis missions: STS-132 and STS-135, and the biofilms formed during spaceflight were characterized. Spaceflight was observed to increase the number of viable cells, biofilm biomass, and thickness relative to normal gravity controls. Moreover, the biofilms formed during spaceflight exhibited a column-and-canopy structure that has not been observed on Earth. The increase in the amount of biofilms and the formation of the novel architecture during spaceflight were observed to be independent of carbon source and phosphate concentrations in the media. However, flagella-driven motility was shown to be essential for the formation of this biofilm architecture during spaceflight. These findings represent the first evidence that spaceflight affects community-level behaviors of bacteria and highlight the importance of understanding how both harmful and beneficial human-microbe interactions may be altered during spaceflight.
Pleiotrophin (PTN) Expression and Function and in the Mouse Mammary Gland and Mammary Epithelial Cells  [PDF]
Sonia M. Rosenfield, Emma T. Bowden, Shani Cohen-Missner, Krissa A. Gibby, Virginie Ory, Ralf T. Henke, Anna T. Riegel, Anton Wellstein
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0047876
Abstract: Expression of the heparin-binding growth factor, pleiotrophin (PTN) in the mammary gland has been reported but its function during mammary gland development is not known. We examined the expression of PTN and its receptor ALK (Anaplastic Lymphoma Kinase) at various stages of mouse mammary gland development and found that their expression in epithelial cells is regulated in parallel during pregnancy. A 30-fold downregulation of PTN mRNA expression was observed during mid-pregnancy when the mammary gland undergoes lobular-alveolar differentiation. After weaning of pups, PTN expression was restored although baseline expression of PTN was reduced significantly in mammary glands of mice that had undergone multiple pregnancies. We found PTN expressed in epithelial cells of the mammary gland and thus used a monoclonal anti-PTN blocking antibody to elucidate its function in cultured mammary epithelial cells (MECs) as well as during gland development. Real-time impedance monitoring of MECs growth, migration and invasion during anti-PTN blocking antibody treatment showed that MECs motility and invasion but not proliferation depend on the activity of endogenous PTN. Increased number of mammospheres with laminin deposition after anti-PTN blocking antibody treatment of MECs in 3D culture and expression of progenitor markers suggest that the endogenously expressed PTN inhibits the expansion and differentiation of epithelial progenitor cells by disrupting cell-matrix adhesion. In vivo, PTN activity was found to inhibit ductal outgrowth and branching via the inhibition of phospho ERK1/2 signaling in the mammary epithelial cells. We conclude that PTN delays the maturation of the mammary gland by maintaining mammary epithelial cells in a progenitor phenotype and by inhibiting their differentiation during mammary gland development.
The Effectiveness of RNAi in Caenorhabditis elegans Is Maintained during Spaceflight  [PDF]
Timothy Etheridge, Kanako Nemoto, Toko Hashizume, Chihiro Mori, Tomoko Sugimoto, Hiromi Suzuki, Keiji Fukui, Takashi Yamazaki, Akira Higashibata, Nathaniel J. Szewczyk, Atsushi Higashitani
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0020459
Abstract: Background Overcoming spaceflight-induced (patho)physiologic adaptations is a major challenge preventing long-term deep space exploration. RNA interference (RNAi) has emerged as a promising therapeutic for combating diseases on Earth; however the efficacy of RNAi in space is currently unknown. Methods Caenorhabditis elegans were prepared in liquid media on Earth using standard techniques and treated acutely with RNAi or a vector control upon arrival in Low Earth Orbit. After culturing during 4 and 8 d spaceflight, experiments were stopped by freezing at ?80°C until analysis by mRNA and microRNA array chips, microscopy and Western blot on return to Earth. Ground controls (GC) on Earth were simultaneously grown under identical conditions. Results After 8 d spaceflight, mRNA expression levels of components of the RNAi machinery were not different from that in GC (e.g., Dicer, Argonaute, Piwi; P>0.05). The expression of 228 microRNAs, of the 232 analysed, were also unaffected during 4 and 8 d spaceflight (P>0.05). In spaceflight, RNAi against green fluorescent protein (gfp) reduced chromosomal gfp expression in gonad tissue, which was not different from GC. RNAi against rbx-1 also induced abnormal chromosome segregation in the gonad during spaceflight as on Earth. Finally, culture in RNAi against lysosomal cathepsins prevented degradation of the muscle-specific α-actin protein in both spaceflight and GC conditions. Conclusions Treatment with RNAi works as effectively in the space environment as on Earth within multiple tissues, suggesting RNAi may provide an effective tool for combating spaceflight-induced pathologies aboard future long-duration space missions. Furthermore, this is the first demonstration that RNAi can be utilised to block muscle protein degradation, both on Earth and in space.
Reduced function and disassembled microtubules of cultured cardiomyocytes in spaceflight
Fen Yang,YingHui Li,Bai Ding,JieLin Nie,HongHui Wang,XiaoYou Zhang,ChunYan Wang,ShuKuan Ling,ChengZhi Ni,ZhongQuan Dai,YingJun Tan,YuMin Wan
Chinese Science Bulletin , 2008, DOI: 10.1007/s11434-008-0167-y
Abstract: Lack of gravity during spaceflight has profound effects on cardiovascular system, but little is known about how the cardiomyocytes respond to microgravity. In the present study, the effects of spaceflight on the structure and function of cultured cardiomyocytes were reported. The primary cultures of neonatal rat cardiomyocytes were carried on Shenzhou-6 spacecraft and activated at 4 h in orbit. 8 samples were fixed respectively at 4, 48 and 96 h after launching for immunofluorescence of cytoskeleton, and 2 samples remained unfixed to analyze contractile and secretory functions of the cultures. Ground samples were treated in our laboratory in parallel. After 115 h spaceflight, video recordings displayed that the number of spontaneous beating sites in flown samples decreased significantly, and the cells in the beating aggregate contracted in fast frequency without synchrony. Radioimmunoassay of the medium showed that the atrial natriuretic peptide secreted from flown cells reduced by 59.6%. Confocal images demonstrated the time-dependant disassembly of mirotubules versus unchanged distribution and organization of microfilaments. In conclusion, above results indicate reduced function and disorganized cytoskeleton of cardiomyocytes in spaceflight, which might provide some cellular basis for further investigations to probe into the mechanisms underlying space cardiovascular dysfunction.
Reduced function and disassembled microtubules of cultured cardiomyocytes in spaceflight
Fen Yang,YingHui Li,Bai Ding,JieLin Nie,HongHui Wang,XiaoYou Zhang,ChunYan Wang,ShuKuan Ling,ChengZhi Ni,ZhongQuan Dai,YingJun Tan,YuMin Wan,

科学通报(英文版) , 2008,
Abstract: Lack of gravity during spaceflight has profound effects on cardiovascular system, but little is known about how the cardiomyocytes respond to microgravity. In the present study, the effects of spaceflight on the structure and function of cultured cardiomyocytes were reported. The primary cultures of neo- natal rat cardiomyocytes were carried on Shenzhou-6 spacecraft and activated at 4 h in orbit. 8 samples were fixed respectively at 4, 48 and 96 h after launching for immunofluorescence of cytoskeleton, and 2 samples remained unfixed to analyze contractile and secretory functions of the cultures. Ground sam- ples were treated in our laboratory in parallel. After 115 h spaceflight, video recordings displayed that the number of spontaneous beating sites in flown samples decreased significantly, and the cells in the beating aggregate contracted in fast frequency without synchrony. Radioimmunoassay of the medium showed that the atrial natriuretic peptide secreted from flown cells reduced by 59.6%. Confocal images demonstrated the time-dependant disassembly of mirotubules versus unchanged distribution and or- ganization of microfilaments. In conclusion, above results indicate reduced function and disorganized cytoskeleton of cardiomyocytes in spaceflight, which might provide some cellular basis for further investigations to probe into the mechanisms underlying space cardiovascular dysfunction.
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