Activation of Adenosine Receptor on Gingival Fibroblasts

Abstract

CD73 (ecto-5′-nucleotidase) on human gingival fibroblasts plays a role in the regulation of intracellular cAMP levels through the generation of adenosine, which subsequently activates adenosine receptors. In this study, we examined the involvement of ecto-adenosine deaminase, which can be anchored to CD26 on human gingival fibroblasts, in metabolizing adenosine generated by CD73, and thus attenuating adenosine receptor activation. Ecto-adenosine deaminase expression on fibroblasts could be increased by pre-treatment with a lysate of Jurkat cells, a cell line rich in cytoplasmic adenosine deaminase. Interestingly, the cAMP response to adenosine generated from 5′-AMP via CD73 and the ability of 5′-AMP to induce hyaluronan synthase 1 mRNA were significantly decreased by the pre-treatment of fibroblasts with Jurkat cell lysate. This inhibitory effect was reversed by the specific adenosine deaminase inhibitor. These results suggest that ectoadenosine deaminase metabolizes CD73-generated adenosine and regulates adenosine receptor activation.

Reduction ofN-Glycolylneuraminic Acid Xenoantigen on Human Adipose Tissue-Derived Stromal Cells/Mesenchymal Stem Cells Leads to Safer and More Useful Cell Sources for Various Stem Cell Therapies

“…After fixation, the cells were stained with 1% alizarin red S in 0.1% NH 4 OH (pH 6.5) for 5 min and then washed with H 2 O. AP activity was investigated at 2 weeks after differentiation using the procedure described previously. 26 AP activity per cell was calculated based on the amount of DNA. DNA content was measured by a modification of the method of Labarca and Paigen.…”

Effects of L‐ascorbic acid 2‐phosphate magnesium salt on the properties of human gingival fibroblasts

“…The protocol was reviewed and approved by the Institutional Review Board of the Osaka University Graduate School of Dentistry, and informed consent was obtained from all subjects participating in the study. Two cell lines of human gingival fibroblasts (HGF 1 and HGF 2) were obtained from biopsies of healthy gingiva from healthy volunteers as previously described (25). Cells of another human gingival fibroblast cell line, Gin-1, were obtained from DS Pharma Biomedical Co., Ltd (Osaka, Japan).…”

The Blockade of Adenosine Deaminase Ameliorates Chronic Experimental Colitis through the Recruitment of Adenosine A2Aand A3Receptors

“…It is noteworthy that the increase in adenosine deaminase expression, occurring in concomitance with the inflammatory bowel reaction, might enhance the catabolic degradation of adenosine, thus resulting in an impairment of immune modulation by endogenous adenosine pathways and a consequent worsening of inflammation and tissue injury. Previous reports suggest that adenosine deaminase may act as a critical regulatory factor, endowed with the ability of limiting bioactive adenosine concentrations and recruitment of downstream receptors in the microenvironment of inflamed tissues (Hashikawa et al, 2006). For example, adenosine deaminase has been linked to the hyperreactivity of some immune cells (dendritic and T cells) during inflammatory reactions (Dong et al, 1997;Desrosiers et al, 2007).…”