Shintaro Hayashi

Tohoku University, Miyagi, Japan

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Publications (3)7.48 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: Pancreatic stellate cells (PSCs) play a pivotal role in pancreatic fibrosis associated with chronic pancreatitis and pancreatic cancer. Connexins (Cxs) allow direct intercellular communications as components of gap junction but also play important roles in the regulation of cell proliferation, cell differentiation, and tissue development. We here examined the expression of Cxs and Cx-mediated regulation of cell functions in PSCs. Methods: Human PSCs were isolated from patients undergoing operation for chronic pancreatitis or pancreatic cancer. The expression of Cxs was examined by reverse transcription polymerase chain reaction, Western blotting, and immunofluorescent staining. The roles of Cxs in PSC functions were examined by using carbenoxolone, a broad-spectrum Cx inhibitor, and small interfering RNA for Cx43. Results: Human activated PSCs expressed a variety of Cxs including Cx43 both in vitro and in vivo. Carbenoxolone inhibited platelet-derived growth factor-BB-induced proliferation and migration, and type I collagen expression in PSCs. In addition, carbenoxolone inhibited the activation of quiescent PSCs to a myofibroblastlike phenotype. Decreased Cx43 expression by small interfering RNA resulted in decreased proliferation and type I collagen expression. Conclusions: Pancreatic stellate cells expressed a variety of Cxs. Connexins, especially Cx43, might regulate the cell functions and activation of PSCs.
    Pancreas 08/2012; 42(2). DOI:10.1097/MPA.0b013e31825c51d6 · 2.96 Impact Factor
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    ABSTRACT: BACKGROUND: The serine protease inhibitor Kazal type 1 (SPINK1), also known as pancreatic secretory trypsin inhibitor (PSTI), is a peptide secreted by pancreatic acinar cells. Genetic studies have shown an association between SPINK1 gene variants and chronic pancreatitis or recurrent acute pancreatitis. The aim of this study was to clarify whether the SPINK1 variants affect the level of serum PSTI. METHODS: One hundred sixty-three patients with chronic pancreatitis or recurrent acute pancreatitis and 73 healthy controls were recruited. Serum PSTI concentrations were determined with a commercial radioimmunoassay kit. RESULTS: Ten patients with the p.N34S variant, 7 with the IVS3+2T>C variant, two with both the p.N34S and the IVS3+2T>C variants, and one with the novel missense p.P45S variant in the SPINK1 gene were identified. The serum PSTI level in patients with no SPINK1 variants was 14.3 ± 9.6 ng/ml (mean ± SD), and that in healthy controls was 10.7 ± 2.2 ng/ml. The PSTI level in patients carrying the IVS3+2T>C variant (5.1 ± 3.4 ng/ml), but not in those with the p.N34S variant (8.9 ± 3.5 ng/ml), was significantly lower than that in the patients without the SPINK1 variants and the healthy controls. The serum PSTI level in the patient with the p.P45S variant was 4.9 ng/ml. Low levels of serum PSTI (<6.0 ng/ml) showed sensitivity of 80 %, specificity of 97 %, and accuracy of 96 % in the differentiation of IVS3+2T>C and p.P45S carriers from non-carriers. CONCLUSION: Serum PSTI levels were decreased in patients with the IVS3+2T>C and p.P45S variants of the SPINK1 gene.
    Journal of Gastroenterology 04/2012; 47(11). DOI:10.1007/s00535-012-0590-3 · 4.52 Impact Factor

  • Suizo 01/2012; 27(4):601-607. DOI:10.2958/suizo.27.601

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