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Nakamura S.,Keio University | Hisamura R.,Keio University | Shimoda S.,Ophtecs Corporation | Shibuya I.,Tottori University | Tsubota K.,Keio University
Nutrition and Metabolism | Year: 2014

Background: Fasting is a rigorous type of dietary restriction that is associate with a number of health benefits. During fasting, ketone bodies significantly increase in blood and become major body fuels, thereby sparing glucose. In the present study, we investigated effects of fasting on hypersensitivity. In addition, we also investigated the possible role of D-beta-hydroxybutyrate provoked by fasting in the attenuation of immediate hypersensitivity by fasting. Methods. Effects of fasting on systemic anaphylaxis were examined using rat model of toluene 2, 4-diisocyanate induced nasal allergy. In addition to food restriction, a ketogenic high-fat and low-carbohydrate diet that accelerates fatty acid oxidation and systemic instillation of D-beta-hydroxybutyrate were employed to elevate internal D-beta-hydroxybutyrate concentration. We assessed relationship between degranulation of rat peritoneal mast cells and internal D-beta-hydroxybutyrate concentration in each treatment. Changes in [Ca2+]i responses to compound 48/80 were analyzed in fura 2-loaded rat peritoneal mast cells derived from the ketogenic diet and fasting. Results: Immediate hypersensitivity reaction was significantly suppressed by fasting. A significant reduction in mast cells degranulation, induced by mast cell activator compound 48/80, was observed in rat peritoneal mast cells delivered from the 24 hours fasting treatment. In addition, mast cells delivered from a ketogenic diet and D-beta-hydroxybutyrate infusion treatment also had reduced mast cell degranulation and systemic D-beta-hydroxybutyrate concentrations were elevated to similar extent as the fasting state. The peak increase in [Ca2+]i was significantly lower in the ketogenic diet and fasting group than that in the control diet group. Conclusions: The results of the present study demonstrates that fasting suppress hypersensitivity reaction, and indicate that increased level of D-beta-hydroxybutyrate by fasting plays an important role, via the stabilization of mast cells, in suppression of hypersensitivity reaction. © 2014 Nakamura et al.; licensee BioMed Central Ltd. Source


Kojima T.,Keio University | Wakamatsu T.H.,Keio University | Dogru M.,Keio University | Dogru M.,Tokyo Dental College | And 13 more authors.
American Journal of Pathology | Year: 2012

An imbalance between free radical generation and radical scavenging antioxidant systems results in oxidative stress, which has been associated with cell injury observed in many age-related diseases. The superoxide dismutase (SOD) family is a major antioxidant system, and deficiency of Cu,Zn-superoxide dismutase-1 (Sod1) in mice leads to many different phenotypes that resemble accelerated aging. In this study we examined the morphologic features and the secretory functions of the lacrimal glands in Sod1 -/- mice. Lacrimal glands showed atrophy of acinar units; fibrosis; infiltration with CD4 + T cells, monocytes, and neutrophils; increased staining with both 4-hydroxy-2-nonenal and 8-hydroxy-2′-deoxyguanosine; increases in apoptotic cells; and the presence of the epithelial-mesenchymal transition in senescent Sod1 -/- mice. Electron microscopy findings revealed evidence of epithelial-mesenchymal transition, presence of swollen and degenerated mitochondria, and the presence of apoptotic cell death in the lacrimal glands of senescent Sod1 -/- mice. These alterations were also associated with the accumulation of secretory vesicles in acinar epithelial cells, decreased production of both stimulated and nonstimulated tears, and a decline in total protein secretion from the lacrimal glands. Our results suggest that Sod1 -/- mice may be a good model system in which to study the mechanism of reactive oxygen species-mediated lacrimal gland alterations. © 2012 American Society for Investigative Pathology. Source


An object of the present invention is to provide a nucleated tablet for contact lens (CL) cleaning that makes it possible to disinfect a CL simply and easily in the presence of a foaming component; a CL cleaning preparation that contains the nucleated tablet; and a method for cleaning a CL. The nucleated tablet for CL cleaning of the invention is a nucleated tablet including an outer shell that contains iodine-based bactericide, a carbonate, an organic acid, and a surfactant having, per partial weight of 2000 out of the molecular weight thereof, less than one hydroxyl group, and an inner nucleus that contains a neutralizing agent, a carbonate, an organic acid, and a surfactant, wherein the inner nucleus is coated for extended release.


Kawashima M.,Keio University | Kawakita T.,Keio University | Okada N.,Keio University | Ogawa Y.,Keio University | And 6 more authors.
Biochemical and Biophysical Research Communications | Year: 2010

A decrease in lacrimal gland secretory function is closely related to aging and leads to an increased prevalence of dry eye syndrome. Since calorie restriction (CR) is considered to prevent functional decline of various organs due to aging, we hypothesized that CR could prevent age-related lacrimal dysfunction. Six-month-old male Fischer 344 rats were randomly divided into ad libitum (AL) and CR (-35%) groups. After 6. months of CR, tear function was examined under conscious state. After euthanasia, lacrimal glands were subjected to histological examination, tear protein secretion stimulation test with Carbachol, and assessment of oxidative stress with 8-hydroxy-2 deoxyguanosine (8-OHdG) and 4-hydroxynonenal (HNE) antibodies. CR significantly improved tear volume and tended to increase tear protein secretion volume after stimulation with Carbachol compared to AL. The acinar unit density was significantly higher in the CR rats compared to AL rats. Lacrimal glands in the CR rats showed a lesser degree of interstitial fibrosis. CR reduced the concentration of 8-OHdG and the extent of staining with HNE in the lacrimal gland, compared to AL. Furthermore, our electron microscopic observations showed that mitochondrial structure of the lacrimal gland obtained from the middle-aged CR rats was preserved in comparison to the AL rats. Collectively, these results demonstrate for the first time that CR may attenuate oxidative stress related damage in the lacrimal gland with preservation of lacrimal gland functions. Although molecular mechanism(s) by which CR maintains lacrimal gland function remains to be resolved, CR might provide a novel therapeutic strategy for treating dry eye syndrome. © 2010 Elsevier Inc. Source


Nakamura S.,Keio University | Nakamura S.,Ophtecs Corporation | Kinoshita S.,Kyoto Prefectural University of Medicine | Yokoi N.,Kyoto Prefectural University of Medicine | And 12 more authors.
PLoS ONE | Year: 2010

Background: Dry eye has shown a marked increase due to visual display terminal (VDT) use. It remains unclear whether reduced blinking while focusing can have a direct deleterious impact on the lacrimal gland function. To address this issue that potentially affects the life quality, we conducted a large-scale epidemiological study of VDT users and an animal study. Methodology/Principal Findings: Cross sectional survey carried out in Japan. A total of 1025 office workers who use VDT were enrolled. The association between VDT work duration and changes in tear film status, precorneal tear stability, lipid layer status and tear secretion were analyzed. For the animal model study, the rat VDT user model, placing rats onto a balance swing in combination with exposure to an evaporative environment was used to analyze lacrimal gland function. There was no positive relationship between VDT working duration and change in tear film stability and lipid layer status. The odds ratio for decrease in Schirmer score, index of tear secretion, were significantly increased with VDT working year (P = 0.012) and time (P = 0.005). The rat VDT user model, showed chronic reduction of tear secretion and was accompanied by an impairment of the lacrimal gland function and morphology. This dysfunction was recovered when rats were moved to resting conditions without the swing. Conclusions/Significance: These data suggest that lacrimal gland hypofunction is associated with VDT use and may be a critical mechanism for VDT-associated dry eye. We believe this to be the first mechanistic link to the pathogenesis of dry eye in office workers. © 2010 Nakamura et al. Source

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