Background-Recent evidence has suggested that reactive oxygen species are important signaling molecules in vascular cells and play a pivotal role in the development of vascular diseases. The activity of NAD(P)H oxidase has been identified as the major source of reactive oxygen species in vascular endothelial cells. However, the precise molecular structure and the mechanism of activation of the oxidase have remained poorly understood. Methods and Results-Here, we investigated the molecular identities and the superoxide-producing activity of endothelial NAD(P)H oxidase. We found that Nox4, a homologue of gp91phox/Nox2, was abundantly expressed in endothelial cells. The expression of Nox4 in endothelial cells markedly exceeded that of other Nox proteins, including gp91phox/Nox2, and was affected by cell growth. Using electron spin resonance and chemiluminescence, we measured the superoxide production and found that the endothelial membranes had an NAD(P)H-dependent superoxide-producing activity comparable to that of the neutrophil membranes, whereas the activity was not enhanced by the 2 recombinant proteins p47phox and p67phox, in contrast to that of the neutrophil membranes. Downregulation of Nox4 by an antisense oligonucleotide reduced superoxide production in endothelial cells in vivo and in vitro. Conclusions-These

There is a relationship between perceived chewing ability (number of foods considered chewable) and physical fitness in this 80-year-old population. Chewing ability may be an independent predictor of physical fitness, thus preventative dental care aimed at preserving chewing ability may be able to enhance activities of daily life and quality of life in very elderly individuals.

Background and Purpose-Reactive oxygen species (ROS) may play a critical role in the regulation of vascular tone and development of vascular diseases, such as stroke. NAD(P)H oxidase is a major source of ROS in vascular cells, including endothelial cells. It has been considered that Nox2 and Nox4 are exclusively expressed among Nox homologues in the endothelial cells of noncerebral blood vessels. However, the precise molecular identity of the NAD(P)H oxidase in the endothelial cells of the cerebral arteries is not fully understood. We examined the expression of Nox homologues and their activation mechanism in the endothelial cells of the cerebral arteries. Methods-We isolated and cultured basilar artery endothelial cells (BAECs) of Sprague-Dawley rats. Expression of NAD(P)H oxidase was examined by reverse-transcription-polymerase chain reaction (RT-PCR) and immunohistological staining. Results-RT-PCR disclosed abundant expression of Nox4 with marginal Nox2 in BAEC. In addition, Nox1 was expressed highly both at mRNA and protein levels in BAECs. Immunohistological staining also showed the prominent expression of Nox1 in the endothelial cells of the basilar artery. With respect to the cytosolic components of NAD(P)H oxidases, BAECs expressed p67 phox and, to a lesser extent, p47 phox , Noxo1, and Noxa1. Both NADH and NADPH induced superoxide production of the BAEC membranes. The phagocyte-type cytosolic components, p47phox and p67 phox , significantly enhanced the NADH-induced superoxide production of the BAEC membranes, whereas the components failed to increase the NADPH-induced superoxide production. Conclusions-Nox1 is highly expressed in the endothelial cells of the cerebral arteries along with Nox2 and Nox4, and the endothelial NAD(P)H oxidase of the cerebral arteries may have a unique activation mechanism by the phagocyte-type cytosolic components.

As quality of life (QOL) could be influenced by oral status in the elderly, we examined whether chewing ability or number of teeth affected QOL in 80-year olds. A cross-sectional survey included dental examination, chewing self-assessment, and a QOL questionnaire. A total of 823 people who were 80 years old participated in this study. QOL was assessed in terms of satisfaction with physical condition, meals, daily living and social interactions, and with face-scale scores. After adjustment for gender, spouse and activities of daily living, dissatisfaction with social interactions was 3.9 times more prevalent in individuals able to chew four foods or fewer than in those chewing 15. Dissatisfaction with physical condition, meals and daily living, and poor face-scale scores, were 2.7, 2.4, 3.4, and 2.4 times more prevalent, respectively, in subjects chewing four foods or fewer. The number of teeth showed little effect. In conclusion, self-assessed chewing ability but not number of teeth was associated with QOL in 80-year-old subjects.