Kaoru Keyama
University of Tokushima
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Clinica Chimica Acta | 2014
Sumika Matsui; Toshiyuki Yasui; Kaoru Keyama; Anna Tani; Takeshi Kato; Hirokazu Uemura; Akira Kuwahara; Toshiya Matsuzaki; Minoru Irahara
BACKGROUND We examined whether high circulating adiponectin level is associated with renal function and is favorable for lipid and glucose metabolism in late postmenopausal women with normal renal function. METHODS We conducted a cross-sectional study in 115 postmenopausal women and divided the subjects into 2 groups (early postmenopausal women and late postmenopausal women). Serum levels of adiponectin, blood urea nitrogen, creatinine (Cr), glucose, insulin and lipid profiles were measured. Glomerular filtration rate (GFR) was estimated by age and Cr. RESULTS Serum adiponectin level in late postmenopausal women was significantly higher than that in early postmenopausal women, and eGFR in late postmenopausal women was significantly lower than that in early postmenopausal women. Adiponectin level showed a negative correlation with eGFR and tended to have a negative correlation with eGFR after adjustments for age, BMI and bioavailable testosterone in all subjects, but adiponectin level did not show a significant correlation with eGFR in late postmenopausal women. Adiponectin level in late postmenopausal women showed a significant negative correlation with triglyceride (TG) and a positive correlation with high-density lipoprotein cholesterol (HDL-C) after adjustments for age and BMI. CONCLUSION In late postmenopausal women with normal renal function, high adiponectin level is associated with favorable lipid profiles. High adiponectin level may be involved in not only eGFR but also other factors in late postmenopausal women.
Journal of Obstetrics and Gynaecology | 2015
Anna Tani; Satoshi Yamamoto; Masahiko Maegawa; Kotaro Kunimi; Sumika Matsui; Kaoru Keyama; Takeshi Kato; Hirokazu Uemura; Akira Kuwahara; Toshiya Matsuzaki; Toshiyuki Yasui; Masaharu Kamada; Takeshi Soeki; Masataka Sata; Minoru Irahara
Endometriosis is a chronic gynaecological disorder that is accompanied by inflammation and oxidative stress. Atherosclerosis has a long subclinical progression in arteries of children and young adults decades before overt clinical manifestations of the disease. In this study, we determined arterial stiffness by measuring brachial-ankle pulse wave velocity (baPWV) in women with endometriosis to assess the presence of subclinical atherosclerosis. We also measured markers of inflammation and oxidative stress in women with endometriosis. baPWV in women with endometriosis aged over 30 years was significantly higher than that in women without endometriosis aged over 30 years (p < 0.05), but not in women aged less than 30. Serum high-sensitivity C-reactive protein level in women with endometriosis was significantly higher than that in controls (p < 0.05). Young women with endometriosis show significantly increased arterial stiffness, suggesting that women with endometriosis need to be cautious of the future onset of atherosclerosis.
Maturitas | 2016
Sumika Matsui; Toshiyuki Yasui; Kana Kasai; Kaoru Keyama; Takeshi Kato; Hirokazu Uemura; Akira Kuwahara; Toshiya Matsuzaki; Minoru Irahara
OBJECTIVE We examined the change in circulating sclerostin level during the menopausal transition and we investigated the associations of sclerositin with hormones and bone turnover markers according to each menopausal stage in cross-sectional and longitudinal studies. METHODS We conducted a cross-sectional study in 200 healthy Japanese women and divided them into 4 stages (reproductive, menopausal transition, early postmenopause and late postmenopause) by menstrual regularity, follicle-stimulating hormone level and years since menopause. Serum levels of sclerostin, bone turnover markers and reproductive hormones were measured. In addition, we examined changes in sclerostin level from the reproductive stage to menopausal transition and from menopausal transition to early postmenopause in a longitudinal study. RESULTS In the cross-sectional study, sclerostin level gradually increased with progression of menopausal stages and showed a significant change during the menopausal transition. Sclerostin levels significantly increased from the reproductive stage to menopausal transition and from menopausal transition to early postmenopause in the longitudinal study. A negative correlation of sclerostin with estradiol was found in early postmenopause. Sclerostin levels were negatively correlated with bone-specific alkaline phosphatase levels in the reproductive stage and menopausal transition and with tartrate-resistant acid phosphatase-5b in menopausal transition. CONCLUSION The change in sclerostin has already occurred in the early stage of menopausal transition and sclerostin level increases with progression of menopausal stages. Elevated sclerostin levels during the menopausal transition may be involved in relative decline in bone formation against increase in bone resorption.
Journal of Obstetrics and Gynaecology | 2017
Sumika Matsui; Toshiyuki Yasui; Kana Kasai; Kaoru Keyama; Kanako Yoshida; Takeshi Kato; Hirokazu Uemura; Akira Kuwahara; Toshiya Matsuzaki; Minoru Irahara
Abstract Oral oestrogen increases the risk of venous thromboembolism (VTE) and increases production of sex hormone-binding globulin (SHBG) in a dose-dependent manner. SHBG has been suggested to be involved in venous thromboembolism. We examined the effects of oral ultra-low-dose oestradiol on circulating levels of SHBG and coagulation parameters, and we compared the effects to those of transdermal oestradiol. Twenty women received oral oestradiol (500 μg) every day (oral ultra-low-dose group) and 20 women received a transdermal patch (50 μg) as a transdermal group. In addition, the women received dydrogesterone continuously (5 mg) except for women who underwent hysterectomy. Circulating SHBG, antithrombin III (ATIII) activity, d-dimer, thrombin–antithrombin complex and plasmin–α2 plasmin inhibitor complex were measured before and 3 months after the start of treatment. SHBG was significantly increased at 3 months in the oral ultra-low-dose group, but not in the transdermal group. However, percent changes in SHBG were not significantly different between the two groups. In both groups, ATIII was significantly decreased at 3 months. In conclusion, even ultra-low-dose oestradiol orally increases circulating SHBG level. However, the magnitude of change in SHBG caused by oral ultra-low-dose oestradiol is small and is comparable to that caused by transdermal oestradiol. Impact statement Oral oestrogen replacement therapy increases production of SHBG which may be related to increase in VTE risk. However, the effect of oral ultra-low-dose oestradiol on SHBG has not been clarified. Even ultra-low-dose oestradiol orally increases circulating SHBG levels, but the magnitude of change in SHBG caused by oral ultra-low-dose oestradiol is small and is comparable to that caused by transdermal oestradiol. VTE risk in women receiving oral ultra-low-dose oestradiol may be comparable to that in women receiving transdermal oestradiol.
Journal of Obstetrics and Gynaecology | 2016
Sumika Matsui; Toshiyuki Yasui; Kana Kasai; Kaoru Keyama; Takeshi Kato; Hirokazu Uemura; Akira Kuwahara; Toshiya Matsuzaki; Minoru Irahara
We examined detailed changes in liver enzymes as surrogate markers for metabolic syndrome and non-alcoholic fatty liver disease (NAFLD) during the menopausal transition and the associations of liver enzymes with lipid profiles related to risk of metabolic syndrome and endocrinological hormones. We divided 393 women into seven stages by menstrual regularity, follicle-stimulating hormone level and years since menopause. Serum levels of alanine aminotranferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase, lipid parameters, glucose, and endocrinological hormones were measured. Both levels of AST and ALT increased towards early post-menopause. AST remained high in late post-menopause but ALT decreased. The AST/ALT ratio decreased towards late menopausal transition and very early post-menopause and increased thereafter. This ratio was negatively correlated with triglyceride. Significant changes in ALT and AST/ALT ratio during the menopausal transition, which were associated with triglyceride, might be involved in the occurrence of metabolic syndrome and NAFLD in Japanese women.
Andrology & Gynecology: Current Research | 2016
Sumika Matsui; Toshiyuki Yasui; Kana Kasai; Kaoru Keyama; Kanako Yoshida; Takeshi Kato; Hirokazu Uemura; Akira Kuwahara; Toshiya Matsuzaki; Minoru Irahara
High Androgenicity and Unfavorable Cardiovascular risk profiles in Non-Obese Women around Menopausal Transition Objective Metabolic changes related to atherogenic diseases have already occurred during menopausal transition rather than after menopause. Also, a change in androgenicity as well as estrogen deficiency occurs around the time of menopausal transition. Focusing on around menopausal transition, we examined the relationships of androgens and sex hormone-binding globulin (SHBG) with blood pressure, lipid profiles and insulin resistance in healthy non-obese women. Methods We conducted a cross-sectional study in healthy non-obese women around menopausal transition (107 women in menopausal transition and 106 women in early postmenopause). Serum levels of estradiol, total testosterone, dehydroepiandrosterone-sulfate, SHBG, lipid profiles, glucose and insulin as well as blood pressure were measured. Results There were significant positive correlations of total testosterone, free testosterone and bioavailable testosterone with systolic and diastolic blood pressure. Total testosterone, free testosterone and bioavailable testosterone showed significant positive correlations with triglyceride and negative correlations with high-density lipoprotein cholesterol (HDL-C). SHBG showed a significant positive correlation with HDL-C and negative correlations with triglyceride and glucose. Conclusions High androgenicity indicated by high levels of free testosterone and bioavailable testosterone or low level of SHBG has unfavorable effects on blood pressure, lipid profiles and glycometabolism in non-obese women around menopausal transition.. .
日本産科婦人科學會雜誌 | 2016
Kaoru Keyama; Takeshi Kato; Kana Kasai; Sumika Matsui; Kanako Yoshida; Minoru Irahara
日本産科婦人科學會雜誌 | 2015
Kaoru Keyama; Anna Tani; Sumika Matsui; Takeshi Kato; Minoru Irahara
Journal of Reproductive Immunology | 2015
Kaoru Keyama; Kana Kasai; Sumika Matsui; Kanako Yoshida; Takeshi Kato; Minoru Irahara
Journal of Minimally Invasive Gynecology | 2015
Takeshi Kato; Kaoru Keyama; Sumika Matsui; Mikio Yamasaki; Kanako Yoshida; Minoru Irahara