Abstract. Endothelial cell (EC) barrier dysfunction is associated with many types of vascular diseases. Investigators have hypothesized that altered EC contraction in conjunction with morphological changes may lead to EC dysfunction. However, the nature of EC contraction and its regulatory mechanisms are not fully understood. In this study we measured thrombin-induced force in bovine arterial EC force using EC fibers that were grown in a collagen matrix. Contraction, which occurred in time-and dose-dependent fashion, was elicited by thrombin. The thrombin-enhanced EC layer permeability was correlated with EC fiber contraction. These results suggest that EC contractile response is involved in alteration of EC barrier function. During the initial period of thrombin stimulation, cadherin complexes were disrupted and cell-to-cell connections were reduced. This was dependent on the transient increase in intracellular calcium concentration and myosin phosphorylation. Rho kinase activation led to rearrangement of actin stress fibers (ASF). Paracellular holes were created in the EC layer in parallel to EC morphological change. Our findings suggest that EC layer permeability is regulated by two distinguishable steps. In the initial period, the cell-to-cell connection was reduced in a calcium-dependent fashion. Subsequently, Rho kinase and ASF-mediated force development increased EC layer permeability via morphological change of EC.

Vascular endothelial cells (ECs), which regulate vascular tonus, serve as a barrier at the interface of vascular tissue. It is generally believed that alteration of this barrier is correlated with diabetic complications; however, a detailed mechanism has not been elucidated. This study examined alteration of bovine arterial EC functions stimulated by a thromboxane A 2 analog (9,11-dideoxy-11␣,9␣-epoxymethano prostaglandin F 2␣ ; U46619) under normal and high-glucose (HG) conditions. U46619 treatment increased EC layer permeability in a timeand dose-dependent fashion. This response initially disrupted calcium-dependent EC-to-EC connections, namely, vascular endothelial cadherin (VE-CaD). Thereafter, EC force development in association with morphological changes was detected employing a reconstituted EC fiber technique, resulting in paracellular hole formation in the EC layer. Thus, we confirmed that U46619-induced enhancement of EC layer permeability involves these sequential steps. Similar trials were performed using a concentration twice that of normal glucose (22.2 mM glucose for 48 h). This treatment significantly enhanced U46619-induced EC layer permeability; furthermore, increases in both rate of VE-CaD disruption and EC fiber contraction were evident. Inhibition of calcium-independent protein kinase C and diacylglycerol kinase indicated that the glucose-dependent increase in VE-CaD disruption was mediated by a calcium-independent mechanism. Moreover, EC contraction was regulated by a typical calcium-independent pathway associated with rho kinase and actin stress fiber. Contraction was also enhanced under HG conditions. This investigation revealed that glucosedependent enhancement of EC layer permeability is related to increases in VE-CaD disruption and EC contraction. Increases in both parameters were mediated by alteration of a calciumindependent pathway.

Objective: This study aimed to clarify the effects of a nutrition education program on vegetable intake of workers, incorporating self-monitoring using a noninvasive skin carotenoid sensor in addition to a seminar to motivate vegetable intake and environmental support through provision of vegetable beverages. Methods:A randomized parallel-group study was conducted with 145 healthy workers (intervention group: 74; comparison group: 71; average age: 42) in Kanagawa prefecture, Japan. A seminar by a registered dietitian to encourage vegetable intake and four weeks of environmental support of vegetable beverage distribution were provided to both groups. In addition, participants in the intervention group measured their vegetable intake by a noninvasive skin carotenoid sensor for 10 weeks. The primary outcome for program evaluation was the amount of vegetable intake, whereas the secondary outcome was its stage of change using the transtheoretical model (TTM). Results:The intervention group showed a significant increase in vegetable intake from pre-intervention at both week 4 and week 10. The TTM stage score showed a significant progress at each period in the intervention group, but there were no differences in changed scores between the two groups. Conclusion:The results suggested that the progress of TTM scores and the increase of vegetable intake was maintained even without the environmental support, due to self-monitoring with a noninvasive skin carotenoid sensor.

Objective: This study examined the effects of a nutrition education program, combining a nutrition seminar with a dietitian with vegetable beverage distribution as an environmental support, on vegetable intake and the stage of change of such intake among workers. Methods: A randomized, parallel-group study was conducted among 194 workers in the Kanagawa prefecture, Japan (intervention group: 100, control group: 94, average age: 43). A nutrition education program was provided only in the intervention group. Primary outcomes for program evaluation were the amount of vegetable intake and the stage of change of this intake using the transtheoretical model (TTM), whereas secondary outcomes were the factors influencing changes in attitude and behavior concerning vegetable intake. Results: The change in vegetable intake from pre-to post-intervention was significantly higher in the intervention group than in the control group, but no significant difference was found 6 weeks after the program. Although the change in the TTM stage score from pre-to post-intervention was significantly higher in the intervention group than in the control group, similar results were observed 6 weeks after the intervention. In addition, factors such as health benefits, interests, self-efficacy, and environmental support from organizations and the community significantly increased in the intervention group. Conclusion: It was suggested that a nutrition education program that combined the nutrition seminar by a dietitian and vegetable beverage distribution may increase the stage of change of vegetable intake and the amount of vegetable intake among workers.