Thrombomodulin ameliorates transforming growth factor-ß1-mediated chronic kidney disease via the G-protein coupled receptor 15/Akt signal pathway.

Kidney fibrosis is the common consequence of chronic kidney diseases that inexorably progresses to end-stage kidney disease with organ failure treatable only with replacement therapy. Since transforming growth factor-ß1 is the main player in the pathogenesis of kidney fibrosis, we posed the hypothesis that recombinant thrombomodulin can ameliorate transforming growth factor-ß1-mediated progressive kidney fibrosis and failure. To interrogate our hypothesis, we generated a novel glomerulus-specific human transforming growth factor-ß1 transgenic mouse to evaluate the therapeutic effect of recombinant thrombomodulin. This transgenic mouse developed progressive glomerular sclerosis and tubulointerstitial fibrosis with kidney failure. Therapy with recombinant thrombomodulin for four weeks significantly inhibited kidney fibrosis and improved organ function compared to untreated transgenic mice. Treatment with recombinant thrombomodulin significantly inhibited apoptosis and mesenchymal differentiation of podocytes by interacting with the G-protein coupled receptor 15 to activate the Akt signaling pathway and to upregulate the expression of anti-apoptotic proteins including survivin. Thus, our study strongly suggests the potential therapeutic efficacy of recombinant thrombomodulin for the treatment of chronic kidney disease and subsequent organ failure.

Protein S protects against allergic bronchial asthma by modulating Th1/Th2 balance.

BACKGROUND: Bronchial asthma is a chronic disease characterized by inflammation, obstruction, and hyperresponsiveness of the airways. There is currently no curative therapy for asthma. Type 2 helper T cell response plays a critical role in the pathogenesis of the disease. Protein S is a glycoprotein endowed with anticoagulant, anti-inflammatory, and anti-apoptotic properties. Whether protein S can suppress bronchial asthma and be useful for its therapy is unknown. METHODS: To address this question here we compared the development of allergen-associated bronchial asthma between wild type and protein S-overexpressing transgenic mice. Mice were sensitized and challenged with ovalbumin. We also evaluated the circulating levels of total and active protein S in patients with bronchial asthma and healthy controls. RESULTS: The circulating level of total protein S and of its active form was significantly decreased in patients with bronchial asthma compared to controls. Allergic protein S transgenic mice showed a significant reduction of airway hyperresponsiveness, lung tissue inflammatory cell infiltration, lung levels of Th2 cytokines and IgE compared to their wild-type counterparts. Administration of exogenous human protein S also decreased airway hyperresponsiveness and Th2-mediated lung inflammation in allergic wild-type mice compared with their untreated mouse counterparts. Human protein S significantly shifted the Th1/Th2 balance to Th1 and promoted the secretion of Th1 cytokines (IL-12, tumor necrosis factor-α) from dendritic cells. CONCLUSIONS: These observations suggest the strong protective activity of protein S against the development of allergic bronchial asthma implicating its potential usefulness for the disease treatment.

Protein S Exacerbates Chronic Liver Injury and Fibrosis.

Protein S is a vitamin K-dependent glycoprotein produced mainly in the liver with anticoagulant, anti-inflammatory, immune-modulatory, and antiapoptotic properties. Protein S exacerbates acute liver injury by prolonging the survival of liver immune cells. However, the effect of protein S on chronic liver injury and fibrosis is unknown. Here, we investigated whether human protein S can affect chronic liver injury and fibrosis. Liver injury/fibrosis was induced by carbon tetrachloride injection in mice overexpressing human protein S and in wild-type mice. Human protein S transgenic mice receiving carbon tetrachloride showed significantly higher circulating levels of liver transaminases, increased liver expression of inflammatory cytokines, significantly more extended liver fibrosis, and areas with DNA breakage after chronic injury compared with wild-type mice. Wild-type mice infused with exogenous human protein S exhibited exacerbated liver injury and increased number of hepatic stellate cells compared with untreated mice. Human protein S inhibited apoptosis and increased Akt pathway activation in hepatic stellate cells. The antiapoptotic activity of protein S may play a role in chronic liver injury and subsequent liver fibrosis.

Anti-apoptotic activity of human matrix metalloproteinase-2 attenuates diabetes mellitus.

BACKGROUND: Chronic progression of diabetes is associated with decreased pancreatic islet mass due to apoptosis of ß-cells. Patients with diabetes have increased circulating matrix metalloproteinase-2 (MMP2); however, the physiological significance has remained elusive. This study tested the hypothesis that MMP2 inhibits cell apoptosis, including islet ß-cells. METHODS: Samples from diabetic patients and newly developed transgenic mice overexpressing human MMP2 (hMMP2) were harnessed, and diabetes was induced with streptozotocin. RESULTS: Circulating hMMP2 was significantly increased in diabetic patients compared to controls and significantly correlated with the serum C-peptide levels. The diabetic hMMP2 transgenic mice showed significant improvements in glycemia, glucose tolerance and insulin secretion compared to diabetic wild type mice. Importantly, the increased hMMP2 levels in mice correlated with significant reduction in islet ß-cell apoptosis compared to wild-type counterparts, and an inhibitor of hMMP2 reversed this mitigating activity against diabetes. The increased activation of Akt and BAD induced by hMMP2 in ß-cells compared to controls, links this signaling pathway to the anti-apoptotic activity of hMMP2, a property that was reversible by both an hMMP2 inhibitor and antibody against integrin-ß3. CONCLUSION: Overall, this study demonstrates that increased expression of hMMP2 may attenuate the severity of diabetes by protecting islet ß-cells from apoptosis through an integrin-mediated activation of the Akt/BAD pathway.

The Medicinal Mushroom, Grifola gargal, Ameliorates Allergic Bronchial Asthma.

Grifola gargal Singer, a medicinal mushroom, has been found to be effective for the prevention and treatment of various chronic inflammatory diseases. However, the effects of G. gargal on allergic diseases are unknown. The present study investigated the effect of G. gargal extract on allergic bronchial asthma. Asthma was induced in mice by ovalbumin sensitization and inhalation. The grade of asthma was compared between mice fed with chow containing G. gargal extract and mice given standard chow. The human mast cell and eosinophilic cell lines were used for in vitro studies. G. gargal extract significantly reduced airway hyperresponsiveness, lung eosinophilic infiltration, lung interleukin (IL)-13 expression, and plasma IgE level and significantly increased IL-10 plasma levels compared to untreated control mice. Spleen regulatory T cells were significantly increased in mice treated with the G. gargal extract compared with untreated control mice. G. gargal extract significantly suppressed expression of cytokines in mast cells and eosinophils compared with control cells. Overall, these observations show that G. gargal extract augments the lung population of regulatory T cells and ameliorates allergic inflammation and airway hyperresponsiveness in mice with allergic bronchial asthma, suggesting the potential therapeutic benefit of G. gargal extract in allergic diseases.

Low dose of alcohol attenuates pro-atherosclerotic activity of thrombin.

BACKGROUND AND AIMS: Thrombin, the active enzyme of the coagulation system, plays a critical role in the pathogenesis of atherosclerosis. Vascular repair promoted by stromal cell-derived factor-1 is a protective process in atherosclerosis. Consumption of low amount of alcohol is believed to reduce the risk of atherosclerotic cardiovascular disease but the mechanism is unclear. This study evaluated whether alcohol can modulate the expression of stromal cell-derived factor-1 and the pro-atherosclerotic activity of thrombin. METHODS: Hepatocytes, monocytes, vascular endothelial and vascular smooth muscle cells were pre-treated with increasing concentrations of ethanol before stimulation with thrombin. The expression of cytokines, chemokines, cell adhesion molecules and epigenetic factors, including histone deacetylases and sirtuins, was evaluated. RESULTS: Thrombin stimulation significantly enhanced the expression of pro-inflammatory cytokines, chemokines and cell adhesion molecules, but significantly decreased the expression of stromal cell-derived factor-1. Pre-treatment of cells with a low dose of ethanol significantly decreased thrombin-induced production of pro-inflammatory cytokines and chemokines, and significantly increased the production of stromal cell-derived factor-1 compared to cells treated with thrombin alone. Ethanol significantly counteracted the decreased expression of histone deacetylases and sirtuins induced by thrombin. Inhibition of histone deacetylase-2 with trichostatin A or with specific siRNA abolished the stimulatory activity of low-dose ethanol on stromal cell-derived factor-1. CONCLUSIONS: Low-dose of ethanol attenuates the inflammatory response and counteracts the reduced expression of stromal cell-derived factor-1 induced by thrombin via an epigenetic mechanism, providing a potential explanation for the protective activity of low dose of alcohol in atherosclerosis.

Usefulness of Small Intestinal Endoscopy in a Case of Adult-onset Familial Mediterranean Fever Associated with Jejunoileitis.

A 66-year-old Japanese man consulted our institution due to paroxysmal and repetitive bouts of fever and abdominal pain that had persisted for more than one week. Capsule and double-balloon endoscopy (DBE) showed petal-shaped mucosal redness with white hemming in the jejunum and ileum, and histopathology of the biopsy specimens revealed villous atrophy and cryptitis with extensive severe neutrophil infiltration. A genetic examination disclosed compound heterozygous MEFV mutations (E84K, P369S), and familial Mediterranean fever was diagnosed. Treatment with colchicine and infliximab was very effective in inducing the complete disappearance of symptoms and normalization of the endoscopic findings. To the best of our knowledge, this is the first report to describe the findings of small intestinal endoscopic images obtained using capsule and DBE.