Endoglin (Eng) is a co-receptor of the transforming growth factor β superfamily playing an important role in endothelial dysfunction. TRC105 (carotuximab) is a monoclonal antibody that blocks Eng and its downstream Smad signaling pathway. Here we have investigated for the first time the effects of TRC105 treatment on the development of endothelial dysfunction induced by 7-ketocholesterol (7K) or high glucose (HG), focusing on Eng expression, signaling, and function. In the hypercholesterolemia study, human aortic endothelial cells (HAoECs) were treated with TRC105 (300 μg/ml) for 1 h, followed by the addition of 7K (10 μg/ml) for another 12 h. In the hyperglycemia study, HAoECs were exposed to HG (45 mM) for 60 h, followed by the addition of TRC105 for another 12 h, and cells treated with 5mM glucose and 40 mM mannitol served as control. Protein levels, adhesion, and transmigration of monocytes were assessed by flow cytometry, mRNA expression was measured by qRT-PCR. 7K and HG treatment increased protein levels of NF-κB and Eng and adhesion and transmigration of monocytes through HAoECs monolayer. TRC105 pretreatment reduced the 7K- or HG-induced Eng protein levels and pSmad1/5 and pSmad2/3 signaling. Despite increased protein levels of P-selectin and VCAM-1, TRC105 mediated blockage of Eng prevented 7K- and HG-induced adhesion and transmigration of monocytes through endothelial monolayers. These results suggest that TRC105-mediated Eng blockage can counteract the hypercholesterolemia- and hyperglycemia-induced endothelial dysfunction in HAoECs, suggesting that Eng might be a potential therapeutic target in disorders associated with elevated cholesterol and glucose levels.

• Keywords
• 7-ketocholesterol, TRC105, endoglin, endothelial dysfunction, high glucose,
• Publication type
• Journal Article MeSH

AIM: To investigate the effect of resveratrol on biliary secretion of cholephilic compounds in healthy and bile duct-obstructed rats. METHODS: Resveratrol (RSV) or saline were administered to rats by daily oral gavage for 28 d after sham operation or reversible bile duct obstruction (BDO). Bile was collected 24 h after the last gavage during an intravenous bolus dose of the Mdr1/Mrp2 substrate azithromycin. Bile acids, glutathione and azithromycin were measured in bile to quantify their level of biliary secretion. Liver expression of enzymes and transporters relevant for bile production and biliary secretion of major bile constituents and drugs were analyzed at the mRNA and protein levels using qRT-PCR and Western blot analysis, respectively. The TR-FRET PXR Competitive Binding Assay kit was used to determine the agonism of RSV at the pregnane X receptor. RESULTS: RSV increased bile flow in sham-operated rats due to increased biliary secretion of bile acids (BA) and glutathione. This effect was accompanied by the induction of the hepatic rate-limiting transporters for bile acids and glutathione, Bsep and Mrp2, respectively. RSV also induced Cyp7a1, an enzyme that is crucial for bile acid synthesis; Mrp4, a transporter important for BA secretion from hepatocytes to blood; and Mdr1, the major apical transporter for xenobiotics. The findings were supported by increased biliary secretion of azithromycin. The TR-FRET PXR competitive binding assay confirmed RSV as a weak agonist of the human nuclear receptor PXR, which is a transcriptional regulator of Mdr1/Mrp2. RSV demonstrated significant hepatoprotective properties against BDO-induced cirrhosis. RSV also reduced bile flow in BDO rats without any corresponding change in the levels of the transporters and enzymes involved in RSV-mediated hepatoprotection. CONCLUSION: Resveratrol administration for 28 d has a distinct effect on bile flow and biliary secretion of cholephilic compounds in healthy and bile duct-obstructed rats.

• Keywords
• Azithromycin, Bile acids, Bile production, Pregnane X receptor, Resveratrol,
• MeSH
• ATP-Binding Cassette Transporters metabolism   MeSH
• Anti-Inflammatory Agents, Non-Steroidal pharmacology   therapeutic use   MeSH
• Antioxidants pharmacology   therapeutic use   MeSH
• Administration, Oral MeSH
• Azithromycin pharmacokinetics   MeSH
• Cholestasis drug therapy   etiology   physiopathology   MeSH
• Glutathione metabolism   MeSH
• Hepatocytes drug effects   metabolism   MeSH
• Liver drug effects   metabolism   physiopathology   MeSH
• Rats MeSH
• Humans MeSH
• Disease Models, Animal MeSH
• Rats, Wistar MeSH
• Pregnane X Receptor MeSH
• Resveratrol MeSH
• Receptors, Steroid agonists   MeSH
• Stilbenes pharmacology   therapeutic use   MeSH
• Bile Acids and Salts chemistry   metabolism   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Humans MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• ATP-Binding Cassette Transporters MeSH
• Anti-Inflammatory Agents, Non-Steroidal MeSH
• Antioxidants MeSH
• Azithromycin MeSH
• Glutathione MeSH
• Pregnane X Receptor MeSH
• Resveratrol MeSH
• Receptors, Steroid MeSH
• Stilbenes MeSH
• Bile Acids and Salts MeSH

C57BL/6J (B6) mice were demonstrated to be the most susceptible and C3H/HeJ (C3H) mice the most resistant to development of atherosclerosis. We hypothesized, whether pro-atherogenic (P-selectin, VCAM-1, and ICAM-1) and anti-atherogenic (endoglin and eNOS) proteins are expressed differently in aorta before the onset of atherosclerosis in these two mouse strains. B6 mice (n = 16) and C3H mice (n = 16) sustained on either chow or cholesterol (1 %) diet for 8 weeks. Biochemical analysis of lipoprotein profile and Western blot analysis of P-selectin, VCAM-1, ICAM-1, eNOS, endoglin, peNOS and TGF-βRII in aorta were performed. Western blot analysis revealed a lower expression of P-selectin by 7 %, VCAM-1 by 51 %, ICAM-1 by 6 %, and a higher expression of eNOS (by 18 %) in C3H mice in comparison with B6 mice after cholesterol diet. Further analysis revealed that cholesterol diet significantly increased the expression of endoglin (by 97 %), TGF-βRII (by 50 %), eNOS (by 21 %) and peNOS (by 122 %) in C3H mice, but not in B6 mice. We propose that lower expression of P-selectin, VCAM-1 and ICAM-1 and higher expression of eNOS in vivo in aorta of C3H mice might represent another potential mechanism for C3H mice being less susceptible to atherosclerosis when compared to B6 mice. In addition, endoglin seems to be involved in an upregulation of eNOS only in C3H mice. Thus, we propose that aorta of C3H mice is less prone to the expression of pro-inflammatory and endothelial dysfunction markers when compared to B6 mice, regardless of lipoprotein profile and before any signs of atherosclerotic process.

• MeSH
• Aorta enzymology   MeSH
• Atherosclerosis enzymology   genetics   prevention & control   MeSH
• Species Specificity MeSH
• Phenotype MeSH
• Genetic Predisposition to Disease MeSH
• Inflammation Mediators metabolism   MeSH
• Cell Adhesion Molecules metabolism   MeSH
• Mice, Inbred C3H MeSH
• Mice, Inbred C57BL MeSH
• Protective Factors MeSH
• Risk Factors MeSH
• Nitric Oxide Synthase Type III metabolism   MeSH
• Animals MeSH
• Check Tag
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH
• Names of Substances
• Inflammation Mediators MeSH
• Cell Adhesion Molecules MeSH
• Nos3 protein, mouse MeSH Browser
• Nitric Oxide Synthase Type III MeSH