Visna-maedi virus-induced expression of interleukin-8 gene in sheep alveolar cells following experimental in vitro and in vivo infection

Tenascin-C (TN-C), an extracellular matrix (ECM) glycoprotein, is specifically induced upon tissue injury and infection and during septic conditions. Carbon monoxide (CO) gas is known to exert various anti-inflammatory effects in various inflammatory diseases. However, the mechanisms underlying the effect of CO on TN-C-mediated inflammation are unknown. In the present study, we found that treatment with LPS significantly enhanced TN-C expression in macrophages. CO gas, or treatment with the CO-donor compound, CORM-2, dramatically reduced LPS-induced expression of TN-C and proinflammatory cytokines while significantly increased the expression of IL-10. Treatment with TN-C siRNA significantly suppressed the effects of LPS on proinflammatory cytokines production. TN-C siRNA did not affect the CORM-2-dependent increase of IL-10 expression. In cells transfected with IL-10 siRNA, CORM-2 had no effect on the LPS-induced expression of TN-C and its downstream cytokines. These data suggest that IL-10 mediates the inhibitory effect of CO on TN-C and the downstream production of proinflammatory cytokines. Additionally, administration of CORM-2 dramatically reduced LPS-induced TN-C and proinflammatory cytokines production while expression of IL-10 was significantly increased. In conclusion, CO regulated IL-10 expression and thus inhibited TN-C-mediated inflammationin vitroandin vivo.

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Differential Normalization of Mucosal Interleukin-8 and Interleukin-6 Activity after Helicobacter pyloriEradication

Infection and Immunity ◽

10.1128/iai.66.10.4742-4747.1998 ◽

1998 ◽

Vol 66 (10) ◽

pp. 4742-4747 ◽

Cited By ~ 50

Author(s):

Takafumi Ando ◽

Kazuo Kusugami ◽

Masahiro Ohsuga ◽

Kenji Ina ◽

Masataka Shinoda ◽

...

Keyword(s):

Mononuclear Cells ◽

Eradication Therapy ◽

Interleukin 8 ◽

Biopsy Specimens ◽

Mucosal Tissues ◽

H Pylori ◽

Triple Treatment

ABSTRACT There is differential resolution of mucosal infiltration with neutrophils and mononuclear cells following successfulHelicobacter pylori eradication. We investigated the effects of H. pylori eradication on mucosal interleukin-8 (IL-8) and IL-6 activity in relation to the resolution of H. pylori-associated gastritis. Eighty-one duodenal ulcer patients with H. pyloriinfection received dual- or triple-treatment eradication therapy, and mucosal biopsy specimens obtained at the initial and follow-up endoscopic examinations were cultured in vitro for 24 h. The levels of IL-8 and IL-6 were measured by enzyme-linked immunosorbent assays. In the 42 patients in whomH. pylori eradication failed, there was little change in the numbers of neutrophils and mononuclear cells infiltrating the mucosa and in IL-8 and IL-6 activity. In the 39 patients in whom H. pylori was eradicated, there was normalization both in the numbers of infiltrating neutrophils and in mucosal IL-8 activity, which was evident within 1 month following therapy. In contrast, there was a gradual resolution of mononuclear cell infiltration over a 6-month period, accompanied by a gradual normalization in IL-6 levels. Addition of H. pylori to cultures of mucosal tissues induced a significant increase in IL-8 activity in both uninfected control subjects and patients from whom H. pylori was eradicated. However, this introduction yielded a significant increase in IL-6 activity only in the latter group. This study indicates a dichotomy in the changes of mucosal IL-8 and IL-6 activity afterH. pylori eradication. The rapid normalization of IL-8 after H. pylori eradication and the ability of H. pylori cells to stimulate IL-8 in control tissues indicate that IL-8 induction is a part of the innate (nonimmune) responses to this organism. In contrast, the results of experiments analyzing IL-6 activity in cultured mucosal tissues suggest that the gradual resolution of mucosal IL-6 activity and mononuclear infiltration after successful eradication observed in vivo may reflect gradually diminishing residual immune responses against H. pylori.

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Interleukin-8 induces neutrophil accumulation but not protease secretion in the canine trachea

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1992.263.6.l708 ◽

1992 ◽

Vol 263 (6) ◽

pp. L708-L713 ◽

Cited By ~ 6

Author(s):

P. G. Jorens ◽

J. B. Richman-Eisenstat ◽

B. P. Housset ◽

P. D. Graf ◽

I. F. Ueki ◽

...

Keyword(s):

Interleukin 8 ◽

Cathepsin G ◽

Human Neutrophils ◽

Secretory Cells ◽

Neutrophil Accumulation ◽

High Concentrations ◽

Granule Secretion ◽

Protease Secretion

The neutrophil enzyme elastase is a potent secretagogue of airway secretory cells, and elastase is present in high concentrations in sputum of patients with hypersecretion (e.g., cystic fibrosis, bronchiectasis). Interleukin-8 (IL-8), a recently discovered cytokine with potent neutrophil chemotactic properties in vitro, is also found in the sputum of these patients. We used an isolated tracheal segment in dogs in vivo to study the effect of IL-8 in causing neutrophil accumulation, elastase release, and secretion (by measuring lysozyme concentrations) in the luminal superfusate. IL-8 caused a potent time-dependent neutrophil accumulation at between 3 and 6 h. The effect was significant at 10(-9) and maximum at 10(-8) M. No increase in free elastase, cathepsin G, or lysozyme was detected in the superfusate. Thus, in contrast to previous studies showing that ragweed antigen causes the accumulation of neutrophil elastase which in turn causes lysozyme secretion, IL-8 causes neutrophil accumulation without granule secretion (or subsequent secretagogue activity). The findings were confirmed with dog and human neutrophils in vitro.

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Gonadotropin-Induced Expression of Messenger Ribonucleic Acid for Cyclooxygenase-2 and Production of Prostaglandins E and F2α in Bovine Preovulatory Follicles Are Regulated by the Progesterone Receptor

Endocrinology ◽

10.1210/en.2005-1575 ◽

2006 ◽

Vol 147 (10) ◽

pp. 4713-4722 ◽

Cited By ~ 43

Author(s):

P. J. Bridges ◽

C. M. Komar ◽

J. E. Fortune

Keyword(s):

Granulosa Cells ◽

Medroxyprogesterone Acetate ◽

Cyclooxygenase 2 ◽

Induced Expression ◽

Messenger Ribonucleic Acid ◽

Preovulatory Follicles ◽

Gonadotropin Surge ◽

Induced Changes

Follicular production of prostaglandins (PGs) is essential for ovulation, but the factors mediating gonadotropin-induced secretion of PGE and PGF2α remain largely unknown. We tested the hypothesis that gonadotropin-induced changes in progesterone and its receptor (PR) mediate the increase in periovulatory PGs. Heifers were treated with PGF2α and GnRH to induce luteolysis and the LH/FSH surge (ovulation occurs ∼30 h after GnRH). Because there are two increases in intrafollicular progesterone/PR mRNA during the bovine periovulatory period, we first examined the temporal pattern of PG production by follicles collected at 0, 3.5, 6, 12, 18, and 24 h after GnRH. Although PGs did not increase in the follicular fluid until 24 h after GnRH, acute secretion of PGs by follicle wall (theca + granulosa cells) was initiated by 18 h and had increased manyfold by 24 h after GnRH. In vitro, FSH and LH induced dramatic transient increases in PG production by follicle wall and granulosa, but not theca, cells isolated from preovulatory follicles (0 h after GnRH). PG accumulation peaked on d 2 of culture, mimicking the secretion pattern after a gonadotropin surge in vivo. In cultures of follicle wall and granulosa cells, the PR antagonist mifepristone (MIFE, 1 μm) inhibited LH-induced PG secretion and the progestin medroxyprogesterone acetate (1 or 10 μm), but not the glucocorticoid dexamethasone (1 or 10 μm), overcame the effect of MIFE on PGs. Semiquantitative RT-PCR revealed that MIFE inhibited LH-induced expression of cyclooxygenase-2 mRNA in granulosa cells in vitro. Again, treatment with medroxyprogesterone acetate overcame the effect of MIFE. Together these results provide strong evidence that periovulatory increases in cyclooxygenase-2 mRNA, PGE, and PGF2α are mediated by gonadotropin-induced increases in progesterone/PR, indicating that in some species there is an important functional relationship between these pathways in the ovulatory cascade.

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