Objectives-Advanced glycation endproducts, AGEs, and its specific receptor, RAGE, are involved in diabetic vascular complications. Endogenous secretory RAGE, esRAGE, has been identified as an alternatively spliced form of RAGE, and shown to act as a decoy receptor for AGE. Here, we measured plasma esRAGE level with a recently developed enzyme-linked immunosorbent assay (ELISA) and examined its association with atherosclerosis in age-and gender-matched 203 type 2 diabetic and 134 nondiabetic subjects. Methods and Results-Plasma esRAGE was inversely associated with carotid or femoral atherosclerosis, as quantitatively measured as intimal-medial thickness (IMT) by arterial ultrasound. Stepwise regression analyses revealed that plasma esRAGE was the third strongest and independent factor associated with carotid IMT, following age and systolic blood pressure. Plasma esRAGE was significantly lower in diabetic patients (0.176Ϯ0.092 ng/mL) than nondiabetic controls (0.253Ϯ0.111). Of note, in all, diabetic or nondiabetic group, plasma esRAGE was significantly and inversely correlated with components of the metabolic syndrome including body mass index, blood pressure, triglyceride, HbA1c, or an insulin resistance index. Stepwise regression analyses showed that body mass index or insulin resistance index was the major factor determining plasma esRAGE in all, nondiabetic or diabetic population. Conclusions-esRAGE is a novel and potential protective factor for the metabolic syndrome and atherosclerosis. Key Words: pathophysiology Ⅲ risk factors Ⅲ type 2 diabetes U nder hyperglycemic conditions, endogenous nonenzymatic glycoxidation of proteins and lipids leads to the formation of heterogeneous products, collectively termed advanced glycation end products (AGEs). 1 AGE engagement of cell surface the receptor for AGE (RAGE) results in cellular signaling including activation of nuclear factor-B, increased expression of cytokines and adhesion molecules, and induction of oxidative stress. 2,3 Transgenic mice overexpressing human RAGE in vascular cells developed advanced nephropathy when they were made diabetic. 4 Thus, the AGE-RAGE system has been thought to play a pivotal role in the development of diabetic microvascular complications.Accumulating evidence suggests that RAGE is also involved in macrovascular complications in diabetes. 5,6 RAGE expression is shown to be upregulated in atherosclerotic plaques of diabetic animals. 7 Some of the human studies also implicate the involvement of RAGE in diabetic vasculopathy. 8,9 Moreover, the group of Stern and Schmidt has shown that augmentation of atherosclerosis in diabetic mice is inhibited by the competition of RAGE with its soluble truncated form termed soluble RAGE (sRAGE), lacking the transmembrane and cytoplasmic domains, produced by recombinant gene engineering. 7,10 Recently, an endogenous secretory RAGE (esRAGE) has been identified as a novel splice variant that directs the synthesis of RAGE proteins carrying all of the extracellular domains but devoid of the transmembrane...

These results indicate that use of oral alfacalcidol was associated with reduced risk for cardiovascular death in this cohort of ESRD patients. The result of this observational study warrants further randomized controlled trials with 1alpha-hydroxy vitamin D3 to confirm the possibility that such medication improves survival of ESRD patients.

Inactivation of glycogen synthase kinase 3␤ (GSK3␤) and the resulting stabilization of free ␤-catenin are critical steps in the activation of Wnt target genes. While Akt regulates GSK3␣/␤ in the phosphatidylinositide 3-OH kinase signaling pathway, its role in Wnt signaling is unknown. Here we report that expression of Wnt or Dishevelled (Dvl) increased Akt activity. Activated Akt bound to the Axin-GSK3␤ complex in the presence of Dvl, phosphorylated GSK3␤ and increased free ␤-catenin levels. Furthermore, in Wnt-overexpressing PC12 cells, dominant-negative Akt decreased free ␤-catenin and derepressed nerve growth factor-induced differentiation. Therefore, Akt acts in association with Dvl as an important regulator of the Wnt signaling pathway.

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We have cloned a cardiovascular-restricted basic helixloop-helix factor that interacts with arylhydrocarbon receptor nuclear translocator (ARNT) in a yeast two-hybrid screen. Cardiovascular helix-loop-helix factor 1 (CHF1) is distantly related to the hairy family of transcriptional repressors. We analyzed its expression pattern during mouse embryo development. At day 8.5, the expression of CHF1 is first detected in the primitive ventricle of the primordial heart tube and persists throughout gestation. In rat hearts, this expression is down-regulated after birth, concurrent with terminal differentiation of cardiomyocytes. In the developing vasculature, CHF1 first appears in the dorsal aorta at day 9.0, which precedes the reported expression of smooth muscle cell markers, and persists into adulthood. In an in vitro system of smooth muscle cell differentiation, CHF1 mRNA was barely detectable in undifferentiated cells but was induced highly in differentiated smooth muscle cells. To determine whether CHF1 might affect the function of ARNT, we performed transfection studies. Co-transfection of CHF1 inhibited ARNT/EPAS1-dependent transcription by 85%, and this inhibition is dose-dependent. In electrophoretic mobility studies, CHF1 inhibited the binding of the ARNT/EPAS1 heterodimer to its target site. Our data suggest that CHF1 functions as a transcriptional repressor and may play an important role in cardiovascular development.

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Aortic preferentially expressed gene (APEG)-1 is a 1.4-kilobase pair (kb) mRNA expressed in vascular smooth muscle cells and is down-regulated by vascular injury. An APEG-1 5-end cDNA probe identified three additional isoforms. The 9-kb striated preferentially expressed gene (SPEG)␣ and the 11-kb SPEG␤ were found in skeletal muscle and heart. The 4-kb brain preferentially expressed gene was detected in the brain and aorta. We report here cloning of the 11-kb SPEG␤ cDNA. SPEG␤ encodes a 355-kDa protein that contains two serine/threonine kinase domains and is homologous to proteins of the myosin light chain kinase family. At least one kinase domain is active and capable of autophosphorylation. In the genome, all four isoforms share the middle three of the five exons of APEG-1, and they differ from each other by using different 5-and 3-ends and alternative splicing. We show that the expression of SPEG␣ and SPEG␤ is developmentally regulated in the striated muscle during C2C12 myoblast to myotube differentiation in vitro and cardiomyocyte maturation in vivo. This developmental regulation suggests that both SPEG␣ and SPEG␤ can serve as sensitive markers for striated muscle differentiation and that they may be important for adult striated muscle function.

A critical stage in malaria transmission occurs in the Anopheles mosquito midgut, when the malaria parasite, Plasmodium, ingested with blood, first makes contact with the gut epithelial surface. To understand the response mechanisms within the midgut environment, including those influenced by resident microbiota against Plasmodium, we focus on a midgut bacteria species' intra-specific variation that confers diversity to the mosquito's competency for malaria transmission. Serratia marcescens isolated from either laboratory-reared mosquitoes or wild populations in Burkina Faso shows great phenotypic variation in its cellular and structural features. Importantly, this variation is directly correlated with its ability to inhibit Plasmodium development within the mosquito midgut. Furthermore, this anti-Plasmodium function conferred by Serratia marcescens requires increased expression of the flagellum biosynthetic pathway that is modulated by the motility master regulatory operon, flhDC. These findings point to new strategies for controlling malaria through genetic manipulation of midgut bacteria within the mosquito.