We previously reported that p38 mitogen-activated protein (MAP) kinase plays a part in sphingosine 1-phosphate-stimulated heat shock protein 27 (HSP27) induction in osteoblast-like MC3T3-E1 cells. In the present study, we investigated whether phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) is involved in the induction of HSP27 in these cells. Sphingosine 1-phosphate time dependently induced the phosphorylation of Akt. Akt inhibitor, 1L-6-hydroxymethyl-chiro-inositol 2-(R)-2-O-methyl-3-O-octadecylcarbonate, reduced the HSP27 induction stimulated by sphingosine 1-phosphate. The sphingosine 1-phosphate-induced phosphorylation of GSK-3beta was suppressed by Akt inhibitor. The sphingosine 1-phosphate-induced HSP27 levels were attenuated by LY294002 or wortmannin, PI3K inhibitors. Furthermore, LY294002 or Akt inhibitor did not affect the sphingosine 1-phosphate-induced phosphorylation of p38 MAP kinase and SB203580, a p38 MAP kinase inhibitor, had little effect on the phosphorylation of Akt. These results suggest that PI3K/Akt plays a part in the sphingosine 1-phosphate-stimulated induction of HSP27, maybe independently of p38 MAP kinase, in osteoblasts.
To determine the levels of mast cell chymase and tryptase activity in the tears of patients with vernal keratoconjunctivitis (VKC).Subjects were 38 VKC patients and 18 healthy controls whose chymase and tryptase activity in tears was measured by enzyme assay. VKC severity was quantified based on the following clinical signs: papillary hypertrophy, conjunctival hyperemia, edema, punctate keratitis, Trantas dots, and mucus production. Of the 38 VKC patients, the degree of disease severity was mild in 13, moderate in 18, and severe in 7.Mean chymase activity and standard deviation in tears was 0.23+/-0.07mU in mild VKC, 0.68+/-0.22mU in moderate VKC, 1.91+/-0.71 mU in severe VKC, and 0.11+/-0.05 mU in healthy controls. The increase in all VKC stages was statistically significant compared to that in healthy control. The degree of chymase activity in tears correlated significantly with VKC severity (r = 0.9245, p < 0.001). High tryptase activity was also detected in the tears of VKC patients, although increased tryptase activity in tears did not correlate with disease severity (r = 0.1999).Chymase activity in tears may thus be a sensitive marker for determining the severity of VKC.
Previously, we reported that levels of chymase activity and its mRNA in cardiac tissues were significantly increased along with progression of cardiac fibrosis in cardiomyopathic hamsters, but the involvement of chymase in the progression of fibrosis has been unclear. In cultured human fibroblasts, the concentration of transforming growth factor-β in the supernatant of medium was significantly increased after injection of human chymase. Furthermore, human chymase dose dependently increased cell proliferation, and this chymase-dependent proliferation was completely suppressed by a chymase inhibitor, Suc-Val-Pro-Phep(OPh)2 (10 μM) or an anti-transforming growth factor-β antibody (100 μg/ml). In this study, we used Bio14.6 and F1B hamsters as cardiomyopathic and control hamsters, respectively. Cardiomyopathic hamsters were orally administered a novel chymase inhibitor, 4-[1-{[bis-(4-methylphenyl)-methyl]-carbamoyl}-3-(2-ethoxy-benzyl)-4-oxo-azetidine-2-yloxy]-benzoic acid (BCEAB; 100 mg/kg per day), or placebo from 5- to 45-week-old. In the placebo-treated group, the cardiac chymase activity in cardiomyopathic hamsters 45 weeks old was significantly increased compared with that in control hamsters. BCEAB significantly reduced the cardiac chymase activity. The indexes (+dP/dt and -dP/dt) of cardiac function were significantly improved by treatment with BCEAB. The mRNA levels of collagen I and collagen III in the placebo-treated hamsters were significantly reduced to 69.6 and 76.5% by treatment with BCEAB, respectively. The fibrotic area in cardiac tissues in the BCEAB-treated hamsters was significantly suppressed to 50.7% compared with that in the placebo-treated treated hamsters. Therefore, the activation of transforming growth factor-β by chymase may play an important role in the progression of cardiac fibrosis and cardiac dysfunction in cardiomyopathy.
It has long been known that high-grade mucoepidermoid carcinoma (MEC) has a poor prognosis, but the detailed molecular and biological mechanisms underlying this are not fully understood. In the present study, the pattern of chymase-positive mast cells, as well as chymase gene expression, in high-grade MEC was compared to that of low-grade and intermediate-grade MEC by using 44 resected tumor samples of MEC of the parotid gland. Chymase expression, as well as chymase-positive mast cells, was found to be markedly increased in high-grade MEC. Significant increases in PCNA-positive cells and VEGF gene expression, as well as lymphangiogenesis, were also confirmed in high-grade MEC. Chymase substrates, such as the latent transforming growth factor-beta (TGF-β) 1 and pro-matrix metalloproteinase (MMP)-9, were also detected immunohistologically in high-grade MEC. These findings suggested that the increased chymase activity may increase proliferative activity, as well as metastasis in the malignant condition, and the inhibition of chymase may be a strategy to improve the poor prognosis of high-grade MEC of the parotid gland.
Cancer cachexia is multifactor syndrome that occurs in 50-80% of cancer patients and accounts for 20% of cancer deaths. We conducted a web questionnaire survey for healthcare professionals(doctors and medical staff), patients and families to clarify the understanding of cancer cachexia. As a result, it was revealed that the understanding of cancer cachexia among patients and families was low. Cancer cachexia was widely recognized by healthcare professionals, but 3 stages of EPCRC was not. Many of healthcare professionals recalled the image of terminal stage of cancer from the term "cancer cachexia", and they lack awareness that cancer cachexia was a disease complication which developed from the early stage of cancer. Furthermore, there were many doctors who were faced with the problem such as a lack of treatment options for cancer cachexia. From these facts, it is necessary to disseminate scientific concept of cancer cachexia and establish standard of care from the early stage.
A 59-year-old postmenopausal woman diagnosed to have primary osteoporosis began to take 60 mg daily of oral raloxifene. The platelet aggregation induced by 1 μM adenosine diphosphate (ADP) and the α2-antiplasmin activity were accelerated significantly after 8 weeks from the beginning of raloxifene-treatment, and gradually deteriorated up to 24 weeks. ADP markedly caused the phosphorylation of Akt in the platelets obtained at 24 weeks. Although there were no subjective complaints at 24 weeks, the medication was stopped with her consent to avoid any adverse effects due to thrombus formation. The platelet hyper-aggregability and Akt phosphorylation induced by ADP disappeared at 4 weeks after the cessation of medication. These results strongly suggest that raloxifene caused the acceleration of platelet aggregation and subclinical thrombus formation through the Akt signal pathway in this case.
