Yurika Yamate

Osaka City University | OCU

UV-B radiation induces sunburn, and neutrophils are pivotal in this inflammation. In this study, we examined the potential involvement of neutrophil extracellular traps (NETs) in ultraviolet B (UVB)-induced skin inflammation, correlating the skin inflammation-mitigating effects of Hochu-ekki-to on UV-B irradiation and NETs. To elucidate NET distrib...

Tranexamic acid (TA) has been reported to exhibit antitumor effects in various mouse models of cancer. However, the mechanism underlying its antitumor effects against endometrial cancer remains to be elucidated. This study was aimed at investigating the efficacy of TA against chronic inflammation-associated endometrial cancer induced by N-methyl-N-...

Background Long-term ultraviolet A (UVA) eye irradiation decreases memory and learning ability in mice. However, the underlying mechanism is still unclear.Objectives In this study, ICR mice were used to study the effects of long-term UVA eye irradiation.Methods The eyes of mice were exposed to UVA from an FL20SBLB-A lamp three times a week for 1 ye...

Metastasis, which accounts for the majority of all cancer-related deaths, occurs through several steps, namely, local invasion, intravasation, transport, extravasation, and colonization. Glycyrrhizin has been reported to inhibit pulmonary metastasis in mice inoculated with B16 melanoma. This study aimed to identify the mechanism through which glycy...

Purpose: Although the onset mechanism of Alzheimer's disease, which co-occurs with aging, has been extensively studied, no effective methods that improve the decline in memory and learning abilities following aging have been developed. Tranexamic acid provided promising results for ameliorating photo-aging and extending the natural lifespan. Howev...

Although various methods for improving the natural aging of skin have been examined, an effective method is currently unavailable. Therefore, in this study, we investigated the effects of Momordica charantia on the natural aging of skin of mice and how sex differences influenced these effects. To this end, we bred female and male hairless mice with...

Ultraviolet (UV) irradiation to the eye induces photoimmunosuppression. In here, we examined the effect of green odor against immunosuppression of contact hypersensitivity in the eye induced by UVB irradiation. Systemic immunosuppression was induced in ICR mice sensitized with 0.5% oxazolone through the skin by a single exposure to UVB. Consecutive...

Long-term eye exposure to ultraviolet (UV)A can effect memory and learning ability. However, the underlying mechanism behind these effects remain unknown. In this study, we used HR-1 mice to study effects of long-term UVA eye irradiation. The eyes or dorsal skin of the mice were exposed to UVA at the dose of 110kj/m2 using an FL20SBLB-A lamp three...

Introduction: In a rapidly aging society, the number of people suffering from osteoporosis keeps increasing. However, effective prevention strategies for osteoporosis are not yet currently available. Objective: In this study, we examined the ameliorative effects of tranexamic acid on osteoporosis in 24-month-old mice. Methods: During the study...

Introduction: Although it is beneficial to protect the skin from natural aging, especially in an aging society, the approach by which this can be achieved is still not well known. Hochu-ekki-to, a Chinese natural medicine, has various advantageous effects; however, there is no report about its influence on skin aging. Objective: Therefore, we ex...

An effective method to protect the skin from natural aging is unknown. Therefore, in this study, we examined the ameliorative effects of tranexamic acid on natural skin aging. In addition, we examined the sex difference in the effect exhibited by tranexamic acid. We bred hairless mice without ultraviolet ray irradiation and physical stress for 2 ye...

An effective method to improve lifespan is not known. Therefore, in this study, we examined the lifespan-extending effect of tranexamic acid in normal mice. We bred hairless mice without exposure to ultraviolet radiation and psychical stress until they died naturally. During the study period, the mice were orally administered tranexamic acid (12 mg...

Vitamin C is a natural nutrient with antioxidant properties and is used as a health supplement. In this study, we examined the effects of intraperitoneal administration of high-dose vitamin C (4 g/kg) on dextran sodium sulfate (DSS)-induced ulcerative colitis. We prepared a mouse ulcerative colitis model by administering DSS for 7 d along with high...

We observed that on long-term breeding, gp91phox-knockout (gp91phox−/−) mice developed white hair. Here, we investigate the origin of this hitherto unexplained phenomenon. Moreover, we investigated the effect of tranexamic acid administration on the hair color in gp91phox−/− mice. We administered tranexamic acid (about 12 mg/kg/day) orally to 9-wee...

Purpose: We have previously reported that skin barrier function is disrupted in mice with colonic tumors induced by azoxymethane (AOM) and dextran sodium sulfate (DSS). We postulated that the impaired skin barrier function was associated with reactive oxygen species derived from gp91phox. In this study, we investigated the mechanisms underlying the...

To date, there have been no treatments developed to ameliorate non‐melanoma skin cancer induced by long‐term exposure to ultraviolet A (UVA) irradiation. In this study, we examined the effects of tranexamic acid (trans‐4‐aminomethyl cyclohexanecarboxylic acid) on long‐term UVA‐induced skin cancer. We exposed the dorsal skin of male hairless mice to...

Photoaging can be induced by long-term ultraviolet (UV)A eye irradiation, but an ameliorating method for such photoaging is not known. In this study, we examined the effects of tranexamic acid (trans-4-aminomethylcyclohexanecarboxylic acid) on photoaging of the skin induced by UVA eye irradiation. We used the C57BL/6 j female mice and locally expos...

Background In modern society, irregular lifestyles are a problem. It is well known that Atopic Dermatitis (AD) occurs during physical stress in people with an irregular lifestyle. We evaluated the influence that day-and-night reversal physical stress has on AD. Methods Six-week-old specific-pathogen-free and conventional NC/Nga male mice were used...

Although we previously reported the exacerbation of dextran sodium sulfate (DSS)-induced ulcerative colitis by ultraviolet (UV) B eye irradiation, we do not yet understand the mechanism behind this phenomenon. In this study, we examined the relationship between the deterioration of DSS-induced ulcerative colitis and clock genes. We induced a mouse...

Ultraviolet (UV) A irradiation induces skin cancer. This study aimed to investigate the effect of UVA irradiation on the eyes, using a mouse model of non-melanoma skin cancer induction. We administered UVA irradiation in the eyes of mice for thrice per week for 15 weeks after application of 7,12-dimethylbenz[a]anthracene (DMBA). Mice receiving UVA...

Background: Ultraviolet (UV) B irradiation has been shown to improve atopic dermatitis (AD). However, the relationship between UVB eye irradiation and AD is not known. This issue was addressed using a mouse model of AD. Methods: The eyes of NC/Nga mice were irradiated with UVB at a dose of 1.0 kJ/m2 using a 20SE sunlamp for the duration of the e...

Atopic dermatitis (AD) is a widespread chronic skin condition that severely affects quality of life and can lead to more serious complications. Although ultraviolet (UV)A eye irradiation can exert various effects on the skin, it is unknown whether UVA can affect AD. To investigate potential associations, we used an NC/Nga mouse model of AD to study...

Background Senna, one of the major stimulant laxatives, is widely used for treating constipation. Chronic senna use has been reported to be associated with colonic disorders such as melanosis coli and/or epithelial hyperplasia. However, there is no obvious information on the influence of chronic senna use on organs except for the intestine. Object...

Active oxygen derived from gp91phox is critical for gestation. However, no reports have evaluated the relationship between reactive oxygen species (ROS) and the number of births in a given pregnancy. In this study, we examined the influence of ROS produced by gp91phox activity on the number of births using C57BL/6j (control) and gp91phox-knockout (...

Background: Ultraviolet (UV) irradiation is well known to promote inflammation and pigmentation of skin. UVB mainly affects dermatitis and pigmentation. Coffee contains a number of polyphenols, such as caffeic acid (CA) and chlorogenic acid (CGA) but their in vivo bioactivity for photobiology remains unclear. Methods: C57BL/6j male mice were irr...

Background: Long-term ultraviolet (UV) A eye irradiation in mice initiates the induction of photoaging. However, the changes in the eye due to long-term exposure to UVA radiation are still unclear. Methods: Male C57BL/6j (control) and inducible nitric oxide synthase knockout (iNOS-/-) mice were used in this study. The eyes of the mice were local...

It has been reported that atopic dermatitis (AD) and ulcerative colitis are related. However, the mechanism underlying this association has not been clarified. We therefore explored how AD induces ulcerative colitis. We developed an AD mouse model (NC/Nga mice) with ulcerative colitis by administering dextran sodium sulfate (DSS) for five days. DSS...

Background: We previously reported that ultraviolet (UV) A eye irradiation reduces the ulcerative colitis induced by dextran sodium sulfate (DSS). This study examined the effects of UVA on colon carcinoma induced by azoxymethane (AOM) and DSS. Methods: We irradiated the eyes of ICR mice with UVA at a dose of 110 kJ/m(2) using an FL20SBLB-A lamp...

Ultraviolet (UV) eye irradiation denatures the cells of the intestine. This study examined the action of UVA and UVB on dextran sodium sulfate (DSS)-induced ulcerative colitis. We produced a mouse model of ulcerative colitis by administering DSS for five days, and irradiated the eye with UVB or UVA for each day of the DSS-treatment period. DSS-indu...

Photoaging is induced by long-term ultraviolet A (UVA) eye irradiation. However, the mechanism of skin damage due to UVA eye irradiation is still not well understood. In this study, we used C57BL/6j and gp91phox knockout (gp91phox(-/-) ) mice for the long-term effects of UVA irradiation. The eye or dorsal skin of the mice was locally exposed to UVA...

Background: Tranexamic acid has an inhibitory action on ultraviolet (UV) B-induced melanocyte activation. This study examined the sex differences in the inhibitory action of tranexamic acid on UVB-induced melanocyte activation. Methods: We irradiated the eye and ear of male and female mice with UVB at a dose of 1.0 kJ/m(2) using a 20SE sunlamp....

It is known that active oxygen plays an important role in a reproduction. However, no report has so far investigated the inluence of active oxygen produced from gp91phox NADPH oxidase on newborns. In this study, we investigated the inluence of active oxygen on the weight of newborns using graviditas gp91phox-knockout (gp91phox-/- ) mice. Gestationa...

BackgroundUVA irradiation before allergic sensitization induces immunosuppression, but the percise mechanism remained unclear. In this study, we examined the influence of UVA irradiation of the eye on contact hypersensitivity (CHS) and the role of mast cells in CHS.Methods We used two types of haptens, fluorescein isothiocyanate (FITC: a Th2 type h...

Context: It has been reported that chronic sennoside use is associated with the development of melanosis coli, colonic adenoma, and/or carcinomas. Objectives: In this study, we investigated the immunological changes in the colon and skin after the administration of senna. Materials and methods: In this study, we investigated the colon and epid...

Background It is known that the levels of hormones secreted from the pituitary gland are increased by ultraviolet B (UVB) eye irradiation. The ovaries are affected by the hormones secreted from the pituitary gland. Therefore, we observed the influence of UVB eye irradiation on the ovaries.Methods In this study, a 2.5 kJ/m2 dose of UVB irradiation w...

Background Tranexamic acid (trans-4-aminomethylcyclohexanecarboxylic acid) is a medicinal amino acid used in skin whitening care. This study examined the effects of tranexamic acid on the melanocyte activation of the skin induced by an ultraviolet (UV) B eye irradiation.Methods The eye or ear was locally exposed to UVB at a dose of 1.0 kJ/m2 using...

Background: Stress is considered to be a major factor in the development of depressive illness. Pregnancy is also a kind of physical stress, and the rate of pregnancy-induced depression is increasing. This

Gp91phox NADPH oxidase enzyme was established earlier to play its role in generating reactive oxygen species. In recent studies, gp91phox NADPH oxidase was reported to be involved in the regulation of ovulation and oestrial cycle. However, its mechanism of action during comparatively stressful gestational period 'gp' is not known. Current study was...

Background. In previous studies, we made the unexpected finding that in mice, ultraviolet (UV)B irradiation of the eye increased the concentration of α-melanocyte-stimulating hormone (α-MSH) in plasma, and systemically stimulated epidermal melanocytes. Aims. To compare the extent of the pigmentation induced by social and restraint stress (which act...

Ultraviolet B (UVB) radiation induces inflammation in the skin specifically at the site of exposure. We unexpectedly found that UVB-induced inflammation was not induced in gp91phox-depleted mice. To test whether gp91phox is directly involved in UVB-induced inflammation, neutrophil- and hyaluronic acid-depleted mice were also irradiated and examined...

Purpose: Irradiation by ultraviolet (UV) B is known to increase the number of Dopa-positive melanocytes in the skin. This study examines the effectiveness of a contact lens for the defense of UVB eye irradiation-induced pigmentation. Methods: A 2.5 kJ/m(2) dose of UVB radiation was delivered by a sunlamp to the eye of C57BL/6j male mice, and cha...

Irradiation by long-term ultraviolet (UV) A initiates the induction of photoaging. However, the mechanisms responsible for the structural changes of skin induced by UVA irradiation of the eye are still unknown. Male hairless mice were used in this study. The eye or dorsal skin was locally exposed to UVA after covering the remaining body surface wit...

Seirogan, a wood creosote, has been used as an antidiarrhetic drug in Asian countries including Japan for many years. This antidiarrhetic has recently been used as a sugar-coated pill because Seirogan has a strong smell. The strong smell of the uncoated form of Seirogan may modulate the defense systems of animals because the sense of smell is impor...

Mite antigens play important roles in the pathogenesis of atopic dermatitis (AD). We recently developed a novel air cleaner (KC-850U) using charged plasma cluster ions to eliminate a variety of allergens from house environments. The present work demonstrates the ability of KC-850U to decrease the symptoms of AD induced by mite allergens. Pooled ser...

We previously reported that topical irradiation of the eye by ultraviolet-B (UVB) activated hypothalamo-pituitary-adrenal axis (HPA-A) of the mouse to increase 3, 4-dihydroxyphenylalanine (DOPA)-positive melanocytes in the skin by an inducible nitric oxide synthase (iNOS)-dependent mechanism. This work demonstrates that irradiation of the eye by ul...

It has been well documented that a long-time irradiation of the eye by a strong light elicits eyestrain and fatigue. To elucidate the mechanism for the induction of light-induced fatigue and asthenopia, changes in the mouse were analyzed after white light-irradiation to the eye. C57BL/6j male mice were irradiated with white light in a specially des...

Because AA (L-ascorbic acid) scavenges various types of free radicals to form MDAA (monodehydroascorbic acid) and DAA (dehydroascorbic acid), its regeneration from the oxidized metabolites is critically important for humans and other animals that lack the ability to synthesize this antioxidant. To study the dynamic aspects of AA metabolism in the c...

Irradiation by ultraviolet A (UVA) initiates the suppression of skin contact hypersensitivity. However, the change in the whole body immunity by UVA irradiation of the eye is still unknown. The mice used in this study were separated into four groups namely: a control, UVA irradiation of the eye, UVA irradiation of the ear, UVA irradiation of the ey...