Publications (2)8.34 Total impact
-
Article: Ghrelin can bind to a species of high density lipoprotein associated with paraoxonase.
[show abstract] [hide abstract]
ABSTRACT: Ghrelin is a 28-residue peptide hormone that is principally released from the stomach during fasting and prior to eating. Two forms are present in human plasma: the unmodified peptide and a less abundant acylated version, in which octanoic acid is attached to the third residue, a serine, via an ester linkage. The acylated form of ghrelin acts as a ligand for the growth hormone secretagogue receptor and can stimulate the release of growth hormone from the pituitary gland. It also initiates behavioral and metabolic adaptations to fasting. Here we show that an immobilized form of ghrelin specifically binds a species of high density lipoprotein associated with the plasma esterase, paraoxonase, and clusterin. Both free ghrelin and paraoxon, a substrate for paraoxonase, can inhibit this interaction. An endogenous species of ghrelin is found to co-purify with high density lipoprotein during density gradient centrifugation and subsequent gel filtration. This interaction links the orexigenic peptide hormone ghrelin to lipid transport and metabolism. Furthermore, the interaction of the esterified hormone ghrelin with a species of HDL containing an esterase suggests a possible mechanism for the conversion of ghrelin to des-acyl ghrelin.Journal of Biological Chemistry 04/2003; 278(11):8877-80. · 4.77 Impact Factor -
Article: A cross-sectional study of the effects of hormon replacement therapy on the cardiovascular disease risk profile in healthy postmenopausal women.
[show abstract] [hide abstract]
ABSTRACT: To assess risk factors for cardiovascular disease in healthy postmenopausal women who had been uninterruptedly on menopausal hormone replacement therapy (HRT) for at least 5 years or who had not received any HRT. Cross-sectional study. The Royal Free Hospital and The Middlesex Hospital. A total of 256 healthy postmenopausal women were analyzed: 73 were taking tibolone, 60 were taking transdermal E(2), 58 were taking conjugated equine estrogens (E), and 65 were not taking any menopausal therapy. Cardiovascular disease risk factors measurement. Total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, lipoprotein(a), insulin, glycated hemoglobin, high sensitivity C-reactive protein, fibrinogen, total antioxidants, and endothelin-1. The different types of HRT induced disparate changes in the various markers of cardiovascular disease. Significantly higher high sensitivity C-reactive protein concentrations were found in women receiving conjugated equine E and tibolone than in women who were not taking any therapy. Glycated hemoglobin was significantly lower in women receiving transdermal E(2) and tibolone compared to women not on HRT. Women on tibolone had significantly higher systolic blood pressure. Because high sensitivity C-reactive protein has recently emerged as an important predictor of cardiovascular disease, the higher high sensitivity C-reactive protein levels observed in women on conjugated equine estrogens and on tibolone have potential important clinical implications.Fertility and Sterility 06/2002; 77(5):945-51. · 3.56 Impact Factor
