Objective: To investigate the relationship between different types and levels of physical activity and cardiovascular disease risk factors, including oxidative stress, blood lipids and insulin resistance, in a healthy female population in China. Method: Healthy women

High homocysteine levels in vitro promote the expression of inflammatory agents responsible for atherogenesis. We investigated the long-term effects of elevated plasma homocysteine on the expression of inflammatory molecules and attempted to elucidate their mechanisms. Male Sprague-Dawley rats (n=36) were randomly divided into 3 groups, which received the control AIN-93G diet, the control diet plus 10g/kg of L-methionine, or that diet without folate (0m/kg) for 14wk. Mild hyperhomocysteinemia was then induced in both experimental groups. The mildly hyperhomocysteinemic rats had markedly increased expression of intracellular adhesion molecule-1 (ICAM-1) in the aorta and elevated serum levels of monocyte chemoattractant protein-1 (MCP-1), compared to the control rats. The activation of nuclear factor B and formation of nitrotyrosine in the aorta were greater in rats with mild hyperhomocysteinemia than in control rats. Serum levels of malonyldialdehyde (MDA) were higher in mildly hyperhomocysteinemic rats than in control rats. These results suggest that the oxidative stress resulting from elevated plasma homocysteine stimulates the activation of nuclear factor B, and consequently increases the expression of the inflammatory factors in vivo. Such an effect may contribute to atherogenesis by enhancing the inflammatory response of the vascular endothelium.

Anthocyanins, present in fruits and vegetables as natural colorants, have been well characterized to possess bioactive properties. Anthocyanin components extracted from black rice (Oryza sativa L.indica) separated by gel filtration and identified using LC-MS were cyanidin 3-glucoside and peonidin 3-glucoside. A standardized extract of black rice pigmented fraction (BRE) containing known proportions of cyanidin 3-glucoside and peonidin 3-glucoside exhibited marked antioxidant activities and free radical scavenging capacities in a battery of in vitro model systems. Significant (p<0.05) prevention of supercoiled DNA strand scission induced by reactive oxygen species (specifically, peroxyl radical and hydroxyl radicals) and suppression of the oxidative modification of human low-density lipoprotein was obtained with BRE. In addition, BRE reduced (p<0.05) the formation of nitric oxide by suppressing inducible nitric oxide synthase expression in murine macrophage RAW264.7 cells, without introducing cell toxicity. The results of this study show that black rice contains anthocyanin pigments with notable antioxidant and anti-inflammatory properties for potential use in nutraceutical or functional food formulations.

The p16 (CDKN2a/INK4a) gene is an important tumor-suppressor gene, involved in the p16/cyclindependent kinase/retinoblastoma gene pathway of cell cycle control. The p16 protein is considered to be a negative regulator of the pathway. The gene encodes an inhibitor of cyclin-dependent kinases 4 and 6, which regulate the phosphorylation of retinoblastoma gene and the G1 to S phase transition of the cell cycle. In the present study, p16 gene promoter hypermethylation patterns and p16 protein expression were analyzed in 100 consecutive untreated cases of primary head and neck squamous cell carcinoma by methylation-specific PCR and immunohistochemical staining. The p16 promoter hypermethylation and apparent loss of p16 protein expression were detected in 27% and 74% of head and neck squamous cell carcinoma, respectively. By-2 test, history of alcohol or tobacco use was significantly correlated with the loss of p16 protein expression (P<005 and.05, respectively). When patient follow-up data were correlated with various clinical and molecular parameters, tumor size and nodal and clinical stage were the strongest prognostic predictors for disease-free survival (tumor recurrence) and for cause-specific and overall survival in patients with head and neck squamous cell carcinoma. Neither p16 promoter hypermethylation nor apparent loss of p16 protein expression appears to be an independent prognostic factor, although loss of p16 protein may be used to predict overall patient survival in early-stage head and neck squamous cell carcinoma.

To develop an accurate new method to measure the partitioning of adipocyte endogenous fatty acids among different metabolic pathways, a critical step toward understanding the regulatory mechanism by which fat disposition is modulated. RESEARCH METHODS AND PROCEDURES: Isolated primary rat adipocytes were pre-incubated with isotope-labeled fatty acids. This allows determination of the specific activity of labeled fatty acids in the endogenous lipid pool. After the removal of exogenous fatty acids, the disposition of endogenous fatty acids into the three major metabolic pathways, namely, oxidation, re-esterification, and release into the medium, was measured independently. This was compared with the total lipolytic release of endogenous fatty acids, as measured by glycerol release. Adipocytes from normal fed and fasted animals were used to determine the effects of physiological variations on the metabolic fate of endogenous fatty acids. RESULTS: In normal fed animals, 0.2% of endogenous fatty acids were oxidized, 50.1% were released, and 49.7% were re-esterified. Fasting doubled the partitioning of fatty acids toward oxidation (p<0.05) in association with increased lipolysis (1.4-fold increase) (p<0.05). This effect was completely abolished by the addition of insulin to the cells (61% reduction) (p<0.05). DISCUSSION: The endogenous fatty acids in adipocytes are actively oxidized. This process can be regulated by altered physiological conditions or by insulin. Over time, it is possible that a small shift of fatty acids toward oxidation could have a significant impact on body fuel economy. This hypothesis needs to be tested.