Yoshihiko Sumi

Oncostatin M, a Cytokine Released by Activated Mononuclear Cells, Induces Epithelial Cell-Myofibroblast Transdifferentiation via Jak/Stat Pathway Activation

Interactions between inflammatory infiltrates and resident tubular epithelial cells may play important roles in the development of tubulointerstitial fibrosis, by promoting epithelial cell-myofibroblast transdifferentiation (EMT). Human proximal tubular epithelial cells transdifferentiated to myofibroblasts after treatment with activated PBMC conditioned medium. mRNA and protein levels for alpha-smooth muscle actin, collagen I, and fibronectin EDA(+) (markers for the myofibroblastic phenotype) were increased, whereas those for E-cadherin and cytokeratin 19 (markers for the epithelial phenotype) were decreased. cDNA microarray analysis was used to identify other changes in gene expression that might point to novel molecular mechanisms driving EMT. Of 1176 array genes, 61 demonstrated at least a twofold change at at least two consecutive time points, of the five time points examined (0.5, 4, 8, 16, and 48 h). Of these genes, 59% were upregulated and 41% were downregulated. The array indicated upregulation of expression of the oncostatin M (OSM)-specific receptor beta subunit from 4 to 48 h after exposure of kidney epithelial cells to activated PBMC conditioned medium, which contained high levels of OSM. In additional experiments, it was demonstrated that OSM induced EMT. OSM activated the Jak/Stat signaling pathway in epithelial cells, and a specific inhibitor of Jak2 blocked both its phosphorylation after exposure to OSM and the induction of alpha-actin and loss of cytokeratin 19 expression. Therefore, OSM is a novel inducer of EMT and is likely to be one of several cytokines produced by inflammatory infiltrates that contribute to this and subsequent tubulointerstitial fibrosis.

Assignment of the human protein C gene (PROC) to chromosome region 2q14→q21 by in situ hybridization

The protein C gene (PROC) was mapped by in situ hybridization. A genomic DNA probe containing the first three exons was 3H-labeled by nick translation, and this was then hybridized in situ to human chromosome preparations. The results localize the gene to 2q14----q21.

A thin honeycomb-patterned film as an adhesion barrier in an animal model of glaucoma filtration surgery.

PurposeTo evaluate the effectiveness and safety of a thin honeycomb-patterned biodegradable film for glaucoma filtration surgery in rabbits. MethodsA 7 μm-thick film made from poly(L-lactide-co-ϵ-caprolactone) was placed in the subconjunctival space in one eye of rabbits, with or without full thickness filtration surgery. The film had a honeycomb-patterned surface that faced the subconjunctival Tenon tissue and the other side was smooth. Filtration surgery was also performed in the fellow eye, which received either no adjunctive treatment or 0.4 mg/mL mitomycin C (MMC; n=6 each). Intraocular pressure (IOP) measurements and bleb evaluations using ultrasound biomicroscopy were performed periodically for 28 days after surgery followed by histologic observation. ResultsPostoperative IOPs of the film-treated eyes were significantly lower than that of control eyes from day 10 to day 28 (P<0.05), but were not significantly different from those of MMC-treated eyes. The subconjunctival filtration space, detected by ultrasound biomicroscopy, disappeared in 5 control eyes, 1 MMC-treated eye, but none of the film-treated eyes. A bleb leak occurred postoperatively in 2 MMC-treated eyes. Histologically, in eyes without filtration surgery, fibrotic tissue with the film partly attached to it was noted on the honeycomb side, but was minimal on the sclera that faced the smooth side of the film. In eyes with filtration surgery, the honeycomb-patterned film lined the inner bleb wall with minimal inflammatory reaction. ConclusionsThe thin honeycomb-patterned film that attached to the inner bleb wall worked as an adhesion barrier in glaucoma filtration surgery in rabbits, which is worthy of further investigation.

[11] Human α2-plasmin inhibitor

Publisher Summary This chapter describes the human α2-plasmin inhibitor. α2 PI molecule has three functional sites: the reactive site, plasminogen-binding site, and cross-linking site. The plasminogen-binding site, located within 20 amino acid residues of the carboxyl-terminal end, binds to the lysine-binding sites of plasminogen, to which fibrin is also bound. Hence, α2PI competitively inhibits the binding of plasminogen to fibrin thus retarding the initiation of the fibrinolytic process because plasminogen binding to fibrin plays an important role in the initiation of fibrinolysis. The high affinity of the plasminogen-binding site for plasmin accelerates the complex formation of plasmin and α2PI, resulting in a rapid inhibition of plasmin. The cross-linking site is located at the second amino acid residue, glutamine, from the amino terminus. The cross-linking of α2PI to fibrin plays a significant role in the inhibition of fibrinolysis because it stabilizes the fibrin clot against fibrinolysis. α2PI can be purified directly from human plasma by immunoaffinity chromatography using a monoclonal antibody.

Curcumin β-D-Glucuronide Plays an Important Role to Keep High Levels of Free-Form Curcumin in the Blood

Curcumin, a polyphenol derived from the rhizome of the naturally occurring plant Curcuma longa, has various pharmacological actions such as antioxidant and anti-inflammatory effects. In this paper, we evaluated the role of its internal metabolite, curcumin β-D-glucuronide (curcumin monoglucuronide, CMG), by investigating curcumin kinetics and metabolism in the blood. Firstly, we orally administered highly bioavailable curcumin to rats to elucidate its kinetics, and observed not only the free-form of curcumin, but also, curcumin in a conjugated form, within the portal vein. We confirmed that curcumin is conjugated when it passes through the intestinal wall. CMG, one of the metabolites, was then orally administered to rats. Despite its high aqueous solubility compared to free-form curcumin, it was not well absorbed. In addition, CMG was injected intravenously into rats in order to assess its metabolic behavior in the blood. Interestingly, high levels of free-form curcumin, thought to be sufficiently high to be pharmacologically active, were observed. The in vivo antitumor effects of CMG following intravenous injection were then evaluated in tumor-bearing mice with the HCT116 human colon cancer cell line. The tumor volume within the CMG group was significantly less than that of the control group. Moreover, there was no significant loss of body weight in the CMG group compared to the control group. These results suggest that CMG could be used as an anticancer agent without the serious side effects that most anticancer agents have.

Assignment of the human α2-plasmin inhibitor gene (PLI) to chromosome region 18p11.1→q11.2 by in situ hybridization

The human alpha 2-plasmin inhibitor gene (PLI) was mapped by in situ hybridization using a genomic DNA probe which contained exons coding for the signal peptide and a portion of the mature protein. The results allowed the chromosome localization of the gene to 18p11.1----q11.2.