Oligonucleotide-targeting periostin ameliorates pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a fatal disease with a median survival of 3-4 years after diagnosis. It is the most frequent form of a group of interstitial pneumonias of unknown etiology. Current available therapies prevent deterioration of lung function but no therapy has shown to improve survival. Periostin is a matricellular protein of the fasciclin 1 family. There is increased deposition of periostin in lung fibrotic tissues. Here we evaluated whether small interfering RNA or antisense oligonucleotide against periostin inhibits lung fibrosis by direct administration into the lung by intranasal route. Pulmonary fibrosis was induced with bleomycin and RNA therapeutics was administered during both acute and chronic phases of the disease. The levels of periostin and transforming growth factor-ß1 in airway fluid and lung tissue, the deposition of collagen in lung tissue and the lung fibrosis score were significantly reduced in mice treated with siRNA and antisense against periostin compared to control mice. These findings suggest that direct administration of siRNA or antisense oligonucleotides against periostin into the lungs is a promising alternative therapeutic approach for the management of pulmonary fibrosis.

Circulating fibrocytes correlate with the asthma control test score.

BACKGROUND: Bronchial asthma is characterised by airway inflammation and remodelling with a decline of lung function. Fibrocytes are bone marrow-derived mesenchymal progenitor cells that play important roles in the pathogenesis of airway remodelling. Several clinical parameters are currently being used in routine clinical practice to assess outcome of therapy in asthma including frequency of rescue with short-acting ß2-agonist and the asthma control test. In this study, we hypothesised that asthma control test is associated with circulating levels of fibrocytes in bronchial asthma. METHODS: There were 20 patients with asthma and seven healthy controls. The number of CD45(+)Collagen I(+) circulating fibrocytes was assessed in the peripheral blood by flow cytometry. RESULTS: The number of circulating fibrocytes was significantly increased in asthma patients with moderate and severe disease compared to controls, and it was inversely correlated with % forced expiratory volume in one second and % forced vital capacity (%FVC). The frequency of inhalation of short-acting ß2 agonist and the asthma control test score was significantly and inversely correlated with the number of circulating fibrocytes. CONCLUSION: The results of this study showed that the number of circulating fibrocytes is inversely correlated with clinical asthma control parameters, further supporting the relevance of measuring circulating fibrocytes as a marker of clinical control in bronchial asthma.

Enhanced wound healing by topical application of ointment containing a low concentration of povidone-iodine.

OBJECTIVE: To investigate the effect of a novel topical wound-healing agent, low-concentration povidone-iodine ointment (LPIO) with a hydrophobic white petrolatum-rich base on skin-wound models in rats and rabbits. METHOD: The therapeutic efficacy of topically applied LPIO was compared to that of standard-concentration povidone-iodine ointment (SPIO) and non-treatment control, using a full-thickness skin-wound model in 24 hairless rats and a full-thickness skin-defect model in rabbit earlobes. The animals were kept under standardised conditions at the Central Research Laboratory of Maruishi Pharmaceutical Co. Ltd. (Osaka, Japan). Therapeutic efficacy was evaluated based on macroscopic wound-size reduction, as well as histopathological and immuno-histochemical examinations. RESULTS: LPIO enhanced wound healing in rat full-thickness skin ulcers, reducing wound size and inflammation, when compared with that in SPIO and non-treatment control. LPIO also markedly improved wound healing in rabbit earlobe ulcers by significantly improving re-epithelialisation, compared with that in SPIO. CONCLUSION: The results of this study suggest that LPIO is a useful topical therapy for ulcerative lesions.

Correlation of circulating dehydroepiandrosterone with activated protein C generation and carotid intima-media thickness in male patients with type 2 diabetes.

AIMS: Dehydroepiandrosterone exerts a protective effect against cardiovascular diseases. However, the relationship of dehydroepiandrosterone with the anticoagulant factor activated protein C, generated by the thrombin-thrombomodulin complex on vascular endothelial cells, remains unknown. This study aimed at studying the relationship between dehydroepiandrosterone and activated protein C generation in patients with Type 2 diabetes. METHODS: Sixty-two male patients with Type 2 diabetes were enrolled in this study. Data obtained from 40 healthy male subjects were used as controls. The plasma levels of dehydroepiandrosterone, the activated protein C-protein C inhibitor complex, high-sensitivity C-reactive protein and monocyte chemoattractant protein-1 were measured by enzyme immunoassays. Carotid intima-media thickness was measured by ultrasonography. RESULTS: The plasma levels of dehydroepiandrosterone (5.15 ± 2.81 vs. 3.76 ± 2.16 ng/ml; P < 0.005) and the activated protein C-protein C inhibitor complex (1.90 ± 1.07 vs. 1.02 ± 0.51 ng/ml; P < 0.001) were significantly lower in patients with diabetes than in normal subjects. Univariate analysis showed a significant correlation of the plasma level of dehydroepiandrosterone with that of the activated protein C-protein C inhibitor complex (r = 0.48, P < 0.001), high-sensitivity C-reactive protein (r = -0.30, P < 0.05) and with the mean intima-media thickness (r = -0.28, P < 0.05) in patients with diabetes. Stepwise multiple regression analysis showed that the plasma level of dehydroepiandrosterone is significantly correlated with the plasma levels of the activated protein C-protein C inhibitor complex (F = 18.06) and high-sensitivity C-reactive protein (F = 4.94). There was no correlation between the plasma levels of dehydroepiandrosterone and monocyte chemoattractant protein-1. CONCLUSIONS: These results suggest that lower circulating levels of dehydroepiandrosterone are associated with decreased activated protein C generation and higher intima-media thickness in patients with Type 2 diabetes.

Heat-killed bacillus Calmette-Guérin and Mycobacterium kansasii antigen 85B combined vaccination ameliorates dermatitis in a mouse model of atopic dermatitis by inducing regulatory T cells.

BACKGROUND: Atopic dermatitis (AD) is a recurrent inflammatory skin disease characterized by dominant T-helper (Th) 2 cytokine response. Bacillus Calmette-Guérin (BCG) has been used for preventing tuberculosis, and is regarded as a strong Th1 cytokine inducer. Antigen (Ag) 85B is a secretory protein present in Mycobacterium species that induces Th1 cytokine production. OBJECTIVES: We investigated the effects of combined vaccination of heat-killed BCG (hkBCG) and Mycobacterium kansasii Ag85B in an AD mouse model. METHODS: For the AD model, keratin 14 promoter-derived caspase-1 overexpressing mice (KCASP1Tg) were used. The mice received a combination therapy of hkBCG at age 3 weeks and Ag85B twice weekly for 11 weeks from the 4th week; Ag85B monotherapy from the 4th week; hkBCG monotherapy at the 3rd week; or control saline. Areas of skin lesions, cytokine mRNA expression and serum interleukin (IL)-18 and immunoglobulin (Ig) E levels were analysed. Inducible Foxp3+ regulatory T cells (iTreg), IL-10-producing T cells (Tr1), and interferon (IFN)-γ/IL-4/IL-17-producing T cells were evaluated in the spleen. RESULTS: Saline-treated mice and hkBCG monotherapy mice spontaneously developed severe dermatitis. However, combined therapy with hkBCG and Ag85B significantly suppressed the development of skin lesions and mast cell infiltrations. Elevations of the serum IgE and IL-18 levels were significantly suppressed with combined therapy. Mice treated with hkBCG and Ag85B had a normal number of iTreg in the spleen, and decreased number of both IL-4- and IL-17-producing CD4+ T cells. The effect of Ag85B monotherapy was limited. CONCLUSIONS: Combined vaccination with hkBCG and Ag85B decreases AD skin lesions by inducing regulatory T cells, suggesting that this vaccination is a potent and novel therapeutic strategy for AD.

1,24-Dihydroxyvitamin D3 (tacalcitol) prevents skin T-cell infiltration.

BACKGROUND: 1,24-Dihydroxyvitamin D3 (tacalcitol), a vitamin D(3) compound, has been used to treat T cell-mediated inflammatory skin diseases such as psoriasis, prurigo and vitiligo. The best-known mechanism of action of this compound is inhibition of the abnormal proliferation of keratinocytes and subsequent maturation; however, its effects on skin T-cell recruitment have not yet been evaluated. Cutaneous lymphocyte-associated antigen (CLA), a surface glycoprotein expressed on T cells, plays a critical role in skin T-cell infiltration. We recently reported that 1,25-dihydroxyvitamin D3 inhibits skin infiltration of CD4+ T cells by suppressing CLA expression on T cells. OBJECTIVES: In this study, we investigated the effect of tacalcitol on CLA epitope decoration and on the levels of gut or lymph node homing receptor expression in human T cells. METHODS: We cultured human T cells with tacalcitol and analysed the effect on CLA expression and skin-homing ability, and evaluated glycosyltransferase mRNAs. We also performed an in vivo study using an antigen-dependent delayed-type hypersensitivity (DTH) mouse model and investigated the effect of tacalcitol on skin-infiltrating CD4+ T cells. RESULTS: Tacalcitol downregulated the expression of CLA and, in parallel, the E- and P-selectin ligand function; however, it exerted no effect on other homing receptors. Subcutaneously and intraperitoneally administered tacalcitol downregulated skin infiltration of effector CD4+ T cells in an in vivo DTH mouse model. CONCLUSIONS: These findings suggest that tacalcitol reduces skin inflammation by partially downregulating CLA expression levels.

IL-4/IL-13 antagonist DNA vaccination successfully suppresses Th2 type chronic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is a chronic disease with a Th2-type-cytokine dominant profile. Several cytokines and related peptides have been used for the treatment of AD but they were ineffective because of their limited biological half-life. We have recently developed a highly efficient mouse dominant negative interleukin (IL)-4/IL-13 antagonist (IL-4DM), which blocks both IL-4 and IL-13 signal transductions. OBJECTIVE: To examine the effects of IL-4DM in vivo in an AD model induced by the repeated exhibition of oxazolone (OX). METHODS: Plasmid DNA was injected intraperitoneally to cause an experimental AD-like dermatitis. The effect was evaluated by ear thickness, histological findings, and mast cells counts in the inflamed skin. The plasma IgE and histamine levels were measured. Cytokine production in skin and splenocytes were also analysed. RESULTS: Mice treated with control plasmid developed marked dermatitis with mast cells and eosinophil infiltration, and had increased plasma IgE and histamine levels with a Th2 type splenocyte cytokine profile. Treatment with mouse IL-4 DNA augmented the ear swelling and thickness with an increased dermal eosinophil count, plasma histamine level, and production of splenocyte IL-4. However, IL-4DM treatment successfully controlled the dermatitis, decreased the mast cell and eosinophil count, and suppressed plasma IgE and histamine levels. Splenocytes produced an increased level of IFN-gamma. CONCLUSION: These data showed that the simultaneous suppression of IL-4/IL-13 signals successfully controlled Th2-type chronic dermatitis. IL-4DM DNA treatment is a potent therapy for AD and related diseases.

Protein C inhibitor regulates hepatocyte growth factor activator-mediated liver regeneration in mice.

BACKGROUND: We recently reported that human protein C inhibitor (PCI), a major inhibitor of activated protein C (APC), inhibits hepatocyte growth factor activator (HGFA) by forming HGFA-PCI complexes in vitro. In this study, we evaluated whether PCI regulates HGFA-mediated liver regeneration in a human PCI gene transgenic (hPCI-Tg) mouse model. METHODS AND RESULTS: After partial hepatectomy in hPCI-Tg and wild-type (WT) mice, the degree of liver regeneration, protein and mRNA expression of HGFA, proHGF activation, plasma levels of PCI and HGFA-PCI complex, and other markers were evaluated in the remnant liver. We also evaluated the effect of anti-human PCI antibody on liver regeneration, which significantly decreased in hPCI-Tg mice compared to WT mice. HGFA mRNA levels in naive and remnant livers after hepatectomy were the same in both WT and hPCI-Tg mice; however, plasma HGFA levels and HGF activation in the liver were lower in hPCI-Tg than in WT mice. There was no difference in plasma levels of transaminases and inflammatory cytokines. However, sinusoidal congestion and bleeding were detected and the serum hyaluronic acid level was elevated in hPCI-Tg mice, indicating that human PCI aggravates sinusoidal injury by inhibiting the cytoprotective effect of APC. APC decreased thrombin-induced IL-6 production in isolated hepatic nonparenchymal cells (NPCs) in vitro. This impaired liver regeneration was reversed by anti-human PCI antibody treatment in vivo. CONCLUSION: PCI regulates liver regeneration after hepatectomy by forming an HGFA-PCI complex and aggravates hepatic NPC injury by inhibiting the cytoprotective effect of APC. Anti-PCI antibody treatment may be a novel therapy for improving liver regeneration.

Protective role of thrombin activatable fibrinolysis inhibitor in obstructive nephropathy-associated tubulointerstitial fibrosis.

BACKGROUND: Thrombin-activatable fibrinolysis inhibitor (TAFI) has been reported to affect wound healing and fibrotic processes, but its role in renal tubulointerstitial fibrosis remains unknown. OBJECTIVE: To study its potential role, we compared TAFI-deficient and wild-type mice for the degree of renal fibrosis caused by unilateral ureteral obstruction (UUO). METHODS: The grade of tubulointerstitial fibrosis, the activity of plasmin, MMP-2 and MMP-9 were evaluated on days 4 and 9 after UUO. RESULTS: The renal content of hydroxyproline and the activity of plasmin, MMP-2 and MMP-9 were significantly increased in kidneys with UUO from TAFI-deficient mice compared with those from wild-type mice. These differences disappeared when animals with UUO from both groups were treated with the plasmin inhibitor tranexamic acid. The renal concentrations of fibrogenic cytokines were also significantly elevated in kidneys with UUO from TAFI-deficient mice compared with those from wild-type mice. CONCLUSION: The results of this study suggest that increased renal activity of plasmin in TAFI-deficient mice causes increased renal interstitial fibrosis in obstructive nephropathy.

A prospective comparison of nursing home-acquired pneumonia with hospital-acquired pneumonia in non-intubated elderly.

There are no prospective comparison of the etiology and clinical outcome between hospital-acquired pneumonia (HAP) and nursing home-acquired pneumonia (NHAP) in non-intubated elderly. This study prospectively evaluated the etiology of HAP and NHAP in non-intubated elderly. A prospective cohort study was carried out in a rural region of Japan where the population over 65 years of age represents 30% of the population. A total of 108 patients were enrolled. There were 33 patients with HAP and 75 with NHAP. Etiologic diagnosis was established in 78.8% of HAP and in 72% of NHAP patients. The most frequent pathogens were Chlamydophila pneumoniae followed by Streptococcus pneumoniae, Staphylococcus aureus and Influenza virus. The frequency of Streptococcus pneumoniae and Influenza virus was significantly higher, whereas the frequency of Staphylococcus aureus and Enterobacteriaceae was significantly lower in NHAP compared to HAP. Performance and nutritional status were significantly worse in patients with HAP than in those with NHAP. Hospital mortality was significantly lower in patients with NHAP compared to those with HAP. This study demonstrated that C. pneumoniae, Streptococcus pneumoniae, Staphylococcus aureus and Influenza virus are frequent causative agents of pneumonia in non-intubated elderly and that the responsible pathogens and clinical outcome differ between NHAP and HAP.

Anti-beta2-glycoprotein I (beta2GPI) monoclonal antibodies with lupus anticoagulant-like activity enhance the beta2GPI binding to phospholipids.

beta2-Glycoprotein I (beta2GPI), a plasma glycoprotein with phospholipid-binding property, is known to be the actual target antigen for autoimmune type anticardiolipin antibodies (aCLs). Certain groups of aCLs (anti-beta2GPI antibodies) exert lupus anticoagulant (LA) activity and perturb the function of vascular endothelial cells. This investigation aimed at highlighting some insights into the molecular basis by which aCLs exert their biological effects by using anti-beta2GPI mAbs with well-characterized epitopes from mice and from patients with antiphospholipid syndrome. Anti-beta2GPI mAbs directed against the third domain (Cof-20 and Cof-22) and fourth domain (Cof-21, EY1C8, and EY2C9) of beta2GPI inhibited the thrombin generation induced by Russell's viper venom in diluted plasma and that induced by the prothrombinase complex reconstituted with purified clotting factors. This anticoagulant activity was abrogated in the presence of an excess amount of phospholipids, thus resembling the LA activity. In stark contrast, anti-beta2GPI mAbs directed against the fifth domain and the carboxy-terminal region of the fourth domain showed no LA-like activity. These findings suggest that the LA activity of anti-beta2GPI antibodies depends on their epitope specificity. Experiments carried out to clarify the mechanism of the LA activity showed that anti-beta2GPI mAbs with LA-like activity, but not those without this effect, enhance the beta2GPI binding to phospholipids. In addition, the F(ab')2 fragment, but not the Fab' fragment, of the anti-beta2GPI mAbs was found to enhance the LA activity and the beta2GPI binding to phospholipids, suggesting that anti-beta2GPI antibodies induce formation of multiple complexes of beta2GPI on the surface of phospholipids because of their bivalent property. This clustering of beta2GPI molecules induced by anti-beta2GPI antibodies, probably because of their multivalent property and epitope specificity, might hinder the lateral mobility and activation of clotting factors on the surface of phospholipids and thus exert LA activity. Clustering of beta2GPI molecules may also explain the molecular mechanism by which anti-beta2GPI antibodies alter the function of leukocytes and endothelial cells. The well-documented heterogeneous LA activity of aCLs (anti-beta2GPI antibodies) may also be explained by their epitope specificity.

Protein C inhibitor directly and potently inhibits activated hepatocyte growth factor activator.

BACKGROUND: Hepatocyte growth factor (HGF) plays an important role in tissue repair and regeneration. HGF activator (HGFA), a factor XIIa-like serine protease, activates HGF precursor to HGF. The precursor of HGFA, proHGFA, is activated by thrombin generated at sites of tissue injury. It is known that protein C inhibitor (PCI), an inhibitor of activated protein C (APC), also inhibits thrombin-thrombomodulin (TM) complex. OBJECTIVES: In the present study we evaluated the effect of PCI on thrombin-catalyzed proHGFA activation in the presence of TM, and on HGFA activity. RESULTS: PCI did not inhibit thrombin-TM-mediated proHGFA activation, but it directly inhibited activated HGFA by forming an enzyme inhibitor complex. The second-order rate constants (m(-1) min(-1)) of the reaction between HGFA and PCI in the presence or absence of heparin (10 U mL(-1)) were 4.3 x 10(6) and 4.0 x 10(6), respectively. The inhibition of HGFA by PCI resulted in a significant decrease of HGFA-catalyzed activation of HGF precursor. Exogenous HGFA added to normal human plasma formed a complex with plasma PCI, and this complex formation was competitively inhibited by APC in the presence of heparin, but very weakly in the absence of heparin. We also demonstrated using recombinant R362A-PCI that Arg362 residue of PCI is important for HGFA inhibition by PCI as judged from the three-dimensional structures constructed using docking models of PCI and HGFA or APC. CONCLUSION: These observations indicate that PCI is a potent inhibitor of activated HGFA, suggesting a novel function for PCI in the regulation of tissue repair and regeneration.

Lipopolysaccharide-induced decreased protein S expression in liver cells is mediated by MEK/ERK signaling and NFkappaB activation: involvement of membrane-bound CD14 and toll-like receptor-4.

BACKGROUND: The vitamin K-dependent protein S (PS), mainly synthesized in hepatocytes and endothelial cells, plays a critical role in the anticoagulant activity of plasma. The decreased plasma level of PS in sepsis is associated with thrombotic tendency, but the mechanism is unclear. OBJECTIVES: In the present study, we examined the effect of lipopolysaccharide (LPS) on PS expression in vivo in rat liver, and in vitro in isolated hepatocytes and sinusoidal endothelial cells (SECs) from normal rats. RESULTS: LPS induced a progressive decrease of plasma PS antigen level up to 12 h with a slight recovery at 24 h, and a transient decrease of liver PS mRNA level at 4-8 h with a complete recovery at 24 h. In the in vitro studies, LPS decreased PS antigen and mRNA levels in both hepatocytes and SECs. After LPS treatment, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) transiently increased in plasma. IL-6 increased the protein expression of PS from hepatocytes, while TNF-alpha decreased it from SECs. LPS increased CD14 in hepatocytes and decreased it in SECs, but did not affect toll-like receptor-4 (TLR-4) expression in both cells. Antirat CD14 and antirat TLR-4 antibodies inhibited LPS-induced NFkappaB activation, and a NFkappaB inhibitor suppressed LPS-induced decreased PS expression in both cells. Furthermore, MEK inhibitor blocked LPS-induced decreased PS expression in both cells. CONCLUSIONS: These findings suggest that LPS-induced decreased PS expression in hepatocytes and SECs is mediated by MEK/ERK signaling and NFkappaB activation and that membrane-bound CD14 and TLR-4 are involved in this mechanism. These findings may explain in part the decreased level of plasma PS and thrombotic tendency in sepsis.

Differential regulation of protein S expression in hepatocytes and sinusoidal endothelial cells in rats with cirrhosis.

BACKGROUND: Liver dysfunction caused by intrasinusoidal microthrombi is frequently observed in patients with cirrhosis after hepatectomy, but the mechanistic pathway remains unknown. OBJECTIVE: In the present study, we evaluated the expression of protein S (PS) in hepatocytes and sinusoidal endothelial cells (SECs) from rats with dimethylnitrosoamine-induced cirrhosis before and after hepatectomy. RESULTS: The plasma level of PS antigen was significantly decreased in cirrhotic rats as compared to control rats treated with vehicle. PS expression was significantly decreased in hepatocytes isolated from cirrhotic rats as compared to controls. In contrast, PS expression was significantly increased in SECs isolated from rats with cirrhosis as compared to controls. Interleukin-6 (IL-6) upregulated the expression of PS in hepatocytes, and tumor necrosis factor-alpha (TNF-alpha) decreased its expression in SECs from both cirrhotic and normal rats. The production of IL-6 and TNF-alpha by Kupffer cells and SECs was decreased in rats with cirrhosis as compared to controls. After hepatectomy, microthrombus formation was markedly enhanced in sinusoids from rats with cirrhosis, and the plasma levels of IL-6 and TNF-alpha were significantly increased in rats with cirrhosis as compared to controls. Furthermore, PS production in SECs was decreased, whereas that in hepatocytes was significantly increased in cirrhotic rats as compared to controls. CONCLUSIONS: These findings suggest that PS expression is differently regulated in hepatocytes and SECs of rats with cirrhosis before and after hepatectomy, that the expression of PS is regulated by locally released inflammatory cytokines, and that decreased expression of PS in SECs may cause liver microthrombus formation, which is frequently observed in patients with cirrhosis after hepatectomy.

Protective role of protein C inhibitor in monocrotaline-induced pulmonary hypertension.

BACKGROUND: Protein C inhibitor (PCI) plays a role in multiple biological processes including fertilization, coagulation, fibrinolysis and kinin systems. OBJECTIVES: We hypothesized that PCI participates in the pathogenesis of pulmonary hypertension. To demonstrate this, we compared the development of pulmonary hypertension in mice overexpressing PCI in the lung with wild-type (WT) mice. Pulmonary hypertension was induced by s.c. injection of 600 mg kg-1 of monocrotaline weekly for 8 weeks. RESULTS: Right ventricular arterial pressure was significantly increased in monocrotaline-treated WT mice compared with that in monocrotaline-treated transgenic mice. Bronchoalveolar lavage fluid (BALF) levels of thrombin-antithrombin complex, monocyte chemoattractant protein-1 and platelet-derived growth factor, and the plasma level of tumor necrosis factor-alpha were significantly increased in monocrotaline-treated WT mice as compared with monocrotaline-treated PCI transgenic mice. Increased level of PCI-thrombin complex was detected in BALF from monocrotaline-treated PCI transgenic mice as compared with saline-treated PCI transgenic mice. CONCLUSIONS: This study showed that increased expression of PCI in the lung is protective against monocrotaline-induced pulmonary hypertension, suggesting a potential beneficial effect of PCI for the therapy of this disease.

Protein S is protective in pulmonary fibrosis.

UNLABELLED: Essentials Epithelial cell apoptosis is critical in the pathogenesis of idiopathic pulmonary fibrosis. Protein S, a circulating anticoagulant, inhibited apoptosis of lung epithelial cells. Overexpression of protein S in lung cells reduced bleomycin-induced pulmonary fibrosis. Intranasal therapy with exogenous protein S ameliorated bleomycin-induced pulmonary fibrosis. SUMMARY: Background Pulmonary fibrosis is the terminal stage of interstitial lung diseases, some of them being incurable and of unknown etiology. Apoptosis plays a critical role in lung fibrogenesis. Protein S is a plasma anticoagulant with potent antiapoptotic activity. The role of protein S in pulmonary fibrosis is unknown. Objectives To evaluate the clinical relevance of protein S and its protective role in pulmonary fibrosis. Methods and Results The circulating level of protein S was measured in patients with pulmonary fibrosis and controls by the use of enzyme immunoassays. Pulmonary fibrosis was induced with bleomycin in transgenic mice overexpressing human protein S and wild-type mice, and exogenous protein S or vehicle was administered to wild-type mice; fibrosis was then compared in both models. Patients with pulmonary fibrosis had reduced circulating levels of protein S as compared with controls. Inflammatory changes, the levels of profibrotic cytokines, fibrosis score, hydroxyproline content in the lungs and oxygen desaturation were significantly reduced in protein S-transgenic mice as compared with wild-type mice. Wild-type mice treated with exogenous protein S showed significant decreases in the levels of inflammatory and profibrotic markers and fibrosis in the lungs as compared with untreated control mice. After bleomycin infusion, mice overexpressing human protein S showed significantly low caspase-3 activity, enhanced expression of antiapoptotic molecules and enhanced Akt and Axl kinase phosphorylation as compared with wild-type counterparts. Protein S also inhibited apoptosis of alveolar epithelial cells in vitro. Conclusions These observations suggest clinical relevance and a protective role of protein S in pulmonary fibrosis.

Anti-inflammatory effect of activated protein C in gastric epithelial cells.

It has been previously demonstrated that activated protein C (APC) plays an important role in the inhibition of inflammation in the gastric mucosa from patients with Helicobacter pylori infection. However, the role of gastric epithelial cells in the anti-inflammatory activity of APC remains unknown. In the present study, we evaluated the anti-inflammatory activity of APC and the expression of thrombomodulin (TM) and endothelial protein C receptor (EPCR) in gastric epithelial cells. The gastric epithelial cell lines, MKN-1 and AGS, and gastric biopsy samples from patients with and without H. pylori infection were used in the experiments. Polymerase chain reaction showed that gastric epithelial cell lines express EPCR and TM. Flow cytometry analysis also showed EPCR expression in both cells. H. pylori infection significantly increased EPCR expression compared with non-infected cells. Similar results were observed in vivo when samples from patients with and without H. pylori infection were analyzed for EPCR protein expression. Significant TM activity was found on AGS and MKN-1 cells stimulated with LPS from Escherichia coli and VacA antigen. APC was able to significantly inhibit the secretion of MCP-1 and IL-1beta induced by H. pylori homogenate in AGS cells. APC also remarkably suppressed the mRNA expression and secretion of MCP-1 from AGS cells infected with H. pylori. These results demonstrated the expression of components of the protein C pathway on gastric epithelial cells and that APC may play a critical role in the protection against gastric mucosal inflammation.

Homeostasis model assessment is a reliable indicator of insulin resistance during follow-up of patients with type 2 diabetes.

OBJECTIVE: To investigate the usefulness of the homeostasis model assessment as an index of insulin resistance (HOMA-IR) for evaluating the clinical course of patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: The usefulness of HOMA-IR and its relationship with insulin resistance assessed by the hyperinsulinemic-euglycemic clamp study (clamp IR) were evaluated in 55 Japanese patients with type 2 diabetes before and after treatment. The patients were subjected to diet (approximately 1,440-1,720 kcal/day) and exercise therapy (walking 10,000 steps daily) for 6 weeks during their hospitalization. RESULTS: Univariate regression analysis disclosed a significant correlation between log-transformed HOMA-IR and log-transformed clamp IR before (r = -0.613, P < 0.0001) and after ( = -0.734, P < 0.0001) treatment. Neither the slopes (-0.71 +/- 0.12 vs. -0.79 +/- 0.09, F = 0.25, P = 0.61) nor the intercepts (y-intercept = 1.67 vs. 1.70, x-intercept = 2.36 vs. 2.15, F = 0.02, P = 0.88) of the regression lines between HOMA-IR and clamp IR were significantly different before and after treatment. There was a significant correlation between the decrease in log-transformed HOMA-IR and the increase in clamp IR during treatment (r = -0.617, P < 0.0001). CONCLUSIONS: HOMA-IR may constitute a useful method not only for diagnosing insulin resistance, but also for follow-up during the treatment of patients with type 2 diabetes.

Protein S exacerbates alcoholic hepatitis by stimulating liver natural killer T cells.

BACKGROUND: Alcohol consumption is a major cause of liver injury but the mechanisms are not completely understood. Protein S (PS) is an anticoagulant glycoprotein with multiple functions. The role of PS in liver injury is unknown. OBJECTIVES: This study investigated the role of PS in acute alcoholic hepatitis. METHODS: A mouse overexpressing human PS (hPS-TG) was generated in which acute hepatitis was induced by intraperitoneal injection of ethanol. RESULTS: The levels of serum liver enzymes and liver tissue inflammatory cytokines and the degree of hepatic steatosis were significantly increased in hPS-TG mice treated with ethanol compared with ethanol-treated wild type (WT) mice. Cell expansion, activation and inhibition of apoptosis were significantly augmented in natural killer T (NKT) cells from hPS-TG mice compared with WT mice. Liver mononuclear cells from hPS-TG mice express higher levels of inflammatory cytokines than those from WT mice after stimulation with a specific stimulant of NKT cells in vitro. In a co-culture system of hepatocytes and NKT cells, the effects of PS on ethanol-mediated cell injury were suppressed by a CD1d neutralizing antibody. Alcoholic liver injury was significantly improved in mice pre-treated with PS siRNA and anti-protein S antibody compared with control mice. Patients with alcoholic hepatitis showed significantly increased plasma PS levels and enhanced liver expression of PS and CD1d compared with controls. CONCLUSIONS: The results of this study suggest that PS exacerbates acute alcoholic hepatitis by inhibiting apoptosis of activated NKT cells.

Plasma levels of agouti-related protein are increased in obese men.

To investigate the relationship between peripheral blood levels of agouti-related protein (AGRP) and various parameters of obesity, we measured the plasma level of AGRP in 15 obese and 15 nonobese men and evaluated its relationship with body mass index (BMI), body fat weight, and visceral, sc, and total fat areas measured by computed tomography, fasting insulin levels, glucose infusion rate during an euglycemic hyperinsulinemic clamp study, serum leptin, and plasma alpha-MSH. Obese men had significantly higher plasma concentrations of AGRP than nonobese men (P < 0.01). Univariate analysis showed that the plasma levels of AGRP are proportionally correlated with BMI, body fat weight, and sc fat area in obese men (BMI: r = 0.732, P < 0.01; body fat weight: r = 0.603, P < 0.02; sc fat area: r = 0.668, P < 0.01) and in all men (BMI: r = 0.839, P < 0.0001; body fat weight: r = 0.818, P < 0.0001; sc fat area: r = 0.728, P < 0.0001). In all men, the plasma levels of AGRP were significantly correlated with the visceral fat area (r = 0.478, P < 0.01), total fat area (r = 0.655, P < 0.0001), fasting insulin level (r = 0.488, P < 0.01), glucose infusion rate (r = -0.564, P < 0.01), serum level of leptin (r = 0.661, P < 0.0001), and the plasma level of alpha-MSH (r = 0.556, P < 0.01). In all subjects, multiple regression analysis showed that the plasma levels of AGRP are significantly (F = 15.522, r = 0.801, P < 0.03) correlated with the plasma levels of alpha-MSH, independently from the total fat area. However, the correlation between plasma levels of AGRP and serum levels of leptin was found to be dependent on the total fat area. In brief, these findings showed that the circulating levels of AGRP are increased in obese men and that they are correlated with various parameters of obesity. Although correlation does not prove causation, the results of this study suggest that peripheral AGRP may play a role in the pathogenesis of obesity.