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Dive into the research topics where Jun-ichi Yamakawa is active.

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Featured researches published by Jun-ichi Yamakawa.


Evidence-based Complementary and Alternative Medicine | 2010

Traditional Chinese Medicine for Chronic Fatigue Syndrome

Rui Chen; Junji Moriya; Jun-ichi Yamakawa; Takashi Takahashi; Tsugiyasu Kanda

More and more patients have been diagnosed as having chronic fatigue syndrome (CFS) in recent years. Western drug use for this syndrome is often associated with many side-effects and little clinical benefit. As an alternative medicine, traditional Chinese medicine (TCM) has provided some evidences based upon ancient texts and recent studies, not only to offer clinical benefit but also offer insights into their mechanisms of action. It has perceived advantages such as being natural, effective and safe to ameliorate symptoms of CFS such as fatigue, disordered sleep, cognitive handicaps and other complex complaints, although there are some limitations regarding the diagnostic standards and methodology in related clinical or experimental studies. Modern mechanisms of TCM on CFS mainly focus on adjusting immune dysfunction, regulating abnormal activity in the hypothalamic-pituitary-adrenal (HPA) axis and serving as an antioxidant. It is vitally important for the further development to establish standards for ‘zheng’ of CFS, i.e. the different types of CFS pathogenesis in TCM, to perform randomized and controlled trials of TCM on CFS and to make full use of the latest biological, biochemical, molecular and immunological approaches in the experimental design.


Journal of International Medical Research | 2008

Chronic Fatigue Syndrome and the Central Nervous System

Rui Chen; Fengxia Liang; Junji Moriya; Jun-ichi Yamakawa; Hiroyuki Sumino; Tsugiyasu Kanda; Takashi Takahashi

An increasing amount of neuroimaging evidence supports the hypothesis that chronic fatigue syndrome patients have structural or functional abnormalities within the brain. Moreover, some neurotrophic factors, neurotransmitters and cytokines have also been evaluated in order to elucidate the mechanism of abnormal neuropsychic findings in chronic fatigue syndrome. In this review, we suggest that the focal point of chronic fatigue syndrome research should be transferred to the central nervous system.


Neurochemical Research | 2008

Brain Atrophy in a Murine Model of Chronic Fatigue Syndrome and Beneficial Effect of Hochu-ekki-to (TJ-41)

Rui Chen; Junji Moriya; Jun-ichi Yamakawa; Takashi Takahashi; Qian Li; Shigeto Morimoto; Kunimitsu Iwai; Hiroyuki Sumino; Nobuo Yamaguchi; Tsugiyasu Kanda

Brain-derived neurotrophic factor (BDNF) is associated with the main symptoms of chronic fatigue sydrome (CFS) and neuron apoptosis. Nevertheless, no study has been performed directly to explore the relationship between CFS, BDNF and neuron apoptosis. We induced a CFS model by six injections of killed Brucella abortus antigen in BALB/c mice and treated them with Hochu-ekki-to (TJ-41). Daily running activity, body weight (BW), ratio of cerebral weight to BW (CW/BW) and expression levels of BDNF and Bcl-2 mRNA in the hippocampus were determined. The daily activity and CW/BW decreased significantly in the CFS model. BDNF and Bcl-2 mRNA expression levels in the hippocampus were suppressed in the CFS model and TJ-41 treated mice, while no significant difference was found between them. We improved a murine model to investigate the relationship between CFS and brain dysfunction. In this model, reduced daily activity might have been associated with decreased hippocampal BDNF mRNA expression, hippocampal apoptosis and brain atrophy. TJ-41 increased the daily running activity of the model, which was independent of brain recovery.


Evidence-based Complementary and Alternative Medicine | 2004

Effect of Hochu-ekki-to (TJ-41), a Japanese Herbal Medicine, on Daily Activity in a Murine Model of Chronic Fatigue Syndrome

Xin Q. Wang; Takashi Takahashi; Shi-jie Zhu; Junji Moriya; Seiichiro Saegusa; Jun-ichi Yamakawa; K Kusaka; Tohru Itoh; Tsugiyasu Kanda

We aimed to evaluate the effect of a Japanese herbal medicine, Hochu-ekki-to (TJ-41), on daily activity in a murine model of chronic fatigue syndrome (CFS). CFS was induced by repeated injection of Brucella abortus (BA) antigen every 2 weeks. TJ-41 was orally administered to mice in a dose of 500 mg/kg/day for 1 week before injecting BA and for 4 weeks thereafter. We evaluated daily running activity in mice receiving TJ-41 as compared with that in untreated mice. Survival of both mouse groups was also monitored during the observation period. Body weight (BW), spleen weight (SW), SW/ BW ratio and expression levels of interleukin-10 (IL-10) mRNA in spleen were determined in both groups at the time of sacrifice. The daily activity was significantly higher in the treated group than in the control. Two mice in the untreated group died 2 days after the second injection of BA, whereas no mice in the group treated with TJ-41 died. The SW and SW/BW ratio were significantly lower in the treated mice than in the control. Suppressed IL-10 mRNA levels were observed in the spleens of the mice treated with TJ-41. Our data suggest that Hochu-ekki-to might possess an inhibitory effect on the marked decrease in running activity following BA injection.


Immunopharmacology and Immunotoxicology | 2009

Hochu-ekki-to combined with interferon-gamma moderately enhances daily activity of chronic fatigue syndrome mice by increasing NK cell activity, but not neuroprotection.

Rui Chen; Junji Moriya; Xianwen Luo; Jun-ichi Yamakawa; Takashi Takahashi; Kenroh Sasaki; Fumihiko Yoshizaki

The purpose of this study was to evaluate the beneficial effect of Hochu-ekki-to (TJ-41) combined with interferon-gamma (IFNγ) on daily activity, immunological and neurological alternation in a mouse model of chronic fatigue syndrome (CFS). CFS was induced by 6 times of repeated injection of Brucella abortus antigen every 2 weeks. Both single TJ-41 and TJ-41 combined with IFNγ increased running activity and thymus weight of CFS mice, while thicker thymic cortex together with elevation of natural killer cell activity was only found in the combined treatment group. No significant improvement was observed in the atrophic brain and decreased expression level of brain-derived neurotrophic factor and Bcl-2 mRNA in hippocampus in both treatment groups. Our results suggest that TJ-41 combined with IFNγ might have a protective effect on the marked reduction in the activity in a model of CFS via normalization of host immune responses, but not neuroprotection.


Endocrine | 2015

The effect of anagliptin treatment on glucose metabolism and lipid metabolism, and oxidative stress in fasting and postprandial states using a test meal in Japanese men with type 2 diabetes

Hirokazu Kakuda; Junji Kobayashi; Masahiro Kakuda; Jun-ichi Yamakawa; Noboru Takekoshi

Keywords Anagliptin Test meal Adiponectin Remnant Renal function 8-OHdGIt has been generally recognized that postprandial hyper-glycemia and hyperlipidemia are highly related to thedevelopment of atherosclerosis [1, 2]. Hyperglycemia isknown to damage vascular endothelial cells, increase oxi-dative stress, promote the expression of adhesion moleculeand inhibit nitric oxide (NO) production [3]. Remnantlipoprotein, an important component of postprandialhyperlipidemia, promotes foam cell formation of macro-phages and proliferation of smooth muscle cells [4].Dipeptidyl peptidase 4 (DPP-4) inhibitors have attractedattention as a new class of anti-diabetic agents for thetreatment of type 2 diabetes [5]. Anagliptin, a member ofthe medication class of DPP-4 inhibitors, has been recentlyavailable in the market in Japan. Animal studies suggestthat anagliptin treatment is associated with improvement ofglucose tolerance either by amelioration of insulin resis-tance or enhancing insulin secretion [6] and the decrease inthe development of atherosclerosis [7]. However, to ourknowledge, there has been no clinical study. In this back-ground, we investigated the effect of anagliptin treatmenton glucose and lipoprotein metabolism in fasting andpostprandial state using a test meal (JANEF E460F18 ,Q.P. Co., Tokyo, Japan).Ten Japanese men with type 2 diabetes (age66.3 ±9.5 years; body mass index (BMI) 26.6 2.2 kg/m


Evidence-based Complementary and Alternative Medicine | 2010

A Kampo Medicine, Boi-ogi-to, Inhibits Obesity in Ovariectomized Rats.

Jun-ichi Yamakawa; Junji Moriya; Takashi Takahashi; Atsushi Ishige; Yoshiharu Motoo; Fumihiko Yoshizaki; Tsugiyasu Kanda

In women facing menopause, end of menstrual activity is accompanied by lower levels of estrogen and gradual weight gain. Postmenopausal weight gain sounds an alarm for womens health and may lead to hyperlipidemia, a lipid increase and glucose intolerance. These phenomena are connected to lifestyle-related diseases such as hypertension, type II diabetes mellitus, arteriosclerosis and metabolic syndrome, making it essential to prevent weight gain in women. A Kampo medicine, Boi-ogi-to, is traditionally used to treat obese conditions, but the mechanism has not yet been investigated. In this experiment, we tested the antiobesity properties of Boi-ogi-to in ovariectomized rats by measuring changes of serum cytokine levels and adipocytokines in fat cells. After treatment with this extract for 6 weeks (20-week-old rats), we found that there was a significant weight decrease in rats treated with Boi-ogi-to as compared with that in the control group. Serum tumor necrosis factor (TNF)-α levels increased significantly in a dose-dependent manner. Gene expression of adipose tissue in uterus also dose dependently showed a significant increase of TNF-α levels, suggesting that secretion of TNF-α by fat cells might play a role in the ability of Boi-ogi-to to inhibit weight gain. While peroxisome proliferators-activated receptor-γ and adiponectin levels did not show a significant difference as compared with those in the control, levels of mRNA expression showed a tendency to increase dose dependently. Resistin did not show any significant change. These results suggest that Boi-ogi-to might be useful for the prevention of obesity that occurs in women with reduction of estrogen.


Evidence-based Complementary and Alternative Medicine | 2013

Significance of Kampo, Japanese Traditional Medicine, in the Treatment of Obesity: Basic and Clinical Evidence

Jun-ichi Yamakawa; Junji Moriya; Kenji Takeuchi; Mio Nakatou; Yoshiharu Motoo; Junji Kobayashi

The cause of obesity includes genetic and environmental factors, including cytokines derived from adipocytes (adipo-cytokines). Although drug therapy is available for obesity, it is highly risky. Our main focus in this review is on the traditional form of Japanese medicine, Kampo, in the treated of obesity. Two Kampo formulas, that is, bofutsushosan (防風通聖散) and boiogito (防己黄耆湯), are covered by the national health insurance in Japan for the treatment of obesity. Various issues related to their action mechanisms remain unsolved. Considering these, we described the results of basic experiments and presented clinical evidence and case reports on osteoarthritis as examples of clinical application of their two Kampo medicine. Traditional medicine is used not only for treatment but also for prevention. In clinical practice, it is of great importance to prove the efficacy of combinations of traditional medicine and Western medicine and the utility of traditional medicine in the attenuation of adverse effects of Western medicine.


Evidence-based Complementary and Alternative Medicine | 2013

Significance of Kampo, Traditional Japanese Medicine, in Supportive Care of Cancer Patients

Jun-ichi Yamakawa; Yoshiharu Motoo; Junji Moriya; Masao Ogawa; Hiroaki Uenishi; Sumiyo Akazawa; Toshiyuki Sasagawa; Matomo Nishio; Junji Kobayashi

The current standard treatment for cancer is a multidisciplinary therapy whereby various types of treatment are properly combined. Chemotherapy with multiple anticancer drugs is now common, and traditional, complementary, and alternative therapies are adopted as supportive measures. Medical care in Japan is distinguished by the ability for patients to access both Western and Kampo medical cares at the same time. There is a high degree of trust in the safety of Kampo therapies because they are practiced by medical doctors who are educated with fundamental diagnosis of Western medicine. Highly reliable clinical studies are being published, demonstrating that palliative or supportive care for cancer patients using Kampo preparations alleviates adverse effects of chemotherapy or radiotherapy. This paper reports the circumstances around cancer care in Japan where traditional therapeutic Kampo formulas are used for patients undergoing cancer treatment with cutting-edge chemotherapy, specifically to alleviate adverse effects of anticancer drugs.


Journal of Epidemiology | 2016

Sex Differences in Associations Among Obesity, Metabolic Abnormalities, and Chronic Kidney Disease in Japanese Men and Women

Masaru Sakurai; Junji Kobayashi; Yasuo Takeda; Shin-ya Nagasawa; Jun-ichi Yamakawa; Junji Moriya; Hiroshi Mabuchi; Hideaki Nakagawa

Aims The present study aimed to investigate relationships among abdominal obesity, metabolic abnormalities, and the prevalence of chronic kidney disease (CKD) in relatively lean Japanese men and women. Participants and methods The participants included 8133 men and 15 934 women between 40 and 75 years of age recruited from the government health check-up center in Kanazawa City, Japan. The prevalence of abdominal obesity, high blood pressure, dyslipidemia, and high fasting plasma glucose levels were assessed according to the Japanese criteria for metabolic syndrome. The estimated glomerular filtration rate (eGFR) was calculated using the modified Modification of Diet in Renal Disease equation for the Japanese population, and participants with an eGFR <60 mL/min/1.73 m2 and/or proteinuria were diagnosed with CKD. Results Overall, 23% of males and 14% of females met criteria for CKD. Having more numerous complicated metabolic abnormalities was significantly associated with a higher odds ratio (OR) of CKD for men and women, irrespective of abdominal obesity. However, there was a sex difference in the OR of CKD for obese participants without metabolic abnormalities, such that abdominal obesity without metabolic abnormalities was significantly associated with a higher OR for men (multivariate-adjusted OR 1.63; 95% confidence interval [CI], 1.16–2.28) but not for women (OR 1.01; 95% CI, 0.71–1.44). Conclusions The present findings demonstrated that obesity without metabolic abnormalities was associated with a higher risk of CKD in men but not women in a relatively lean Japanese population.

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Junji Moriya

Kanazawa Medical University

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Tsugiyasu Kanda

Kanazawa Medical University

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Junji Kobayashi

Kanazawa Medical University

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Rui Chen

Kanazawa Medical University

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Yoshiharu Motoo

Kanazawa Medical University

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K Kusaka

Kanazawa Medical University

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Seiichiro Saegusa

Kanazawa Medical University

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Tohru Itoh

Kanazawa Medical University

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Fumihiko Yoshizaki

Tohoku Pharmaceutical University

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