研究者詳細 - 伊藤　裕

論文 - 伊藤　裕

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Clinical significance of 'cardiometabolic memory': a systematic review of randomized controlled trials

Itoh, H., Kurihara, I., Miyashita, K. and Tanaka, M.

Hypertens Res 40 （ 6 ） 526 - 534 2017年06月

ISSN 0916-9636

'Cardiometabolic memory' has been proposed based on clinical evidence to explain how, even after the cessation of a clinical trial, the superiority of one treatment over the outcome persists. To understand the cardiometabolic memory phenomenon, we performed a systematic review of randomized controlled trials (RCTs) using PubMed in August 2016. The search terms 'randomized controlled trial', 'post-trial follow-up' and 'diabetes, hypertension or dyslipidemia' were used, and articles published after the year 2000 were searched. We judged the memory phenomenon to be positive when the cardiovascular outcome at the end of the post-trial follow-up period in the intervention group was significantly superior even though the favorable control of a risk factor (blood glucose, blood pressure or lipid level) during the trial period was lost after the cessation of the intervention. Among 907 articles retrieved in the initial screening, 21 articles were judged as describing a positive memory phenomenon. Eight, six and seven of the articles concerned diabetes, hypertension and dyslipidemia, respectively. Transient intensive glucose lowering rather easily induced memory for the suppression of diabetic microangiopathies, while memory for the suppression of macroangiopathies tended to be first evident in the post-trial follow-up period. Transient intensive blood pressure lowering was generally effective in the formation of memory for the suppression of cardiovascular events and had an especially strong impact on risk reduction of chronic heart failure. Transient intensive LDL cholesterol lowering clearly had a long-term beneficial effect on risk reduction of cardiovascular events. Our systematic review revealed the clinical relevance of cardiometabolic memory.

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Bile acid binding resin prevents fat accumulation through intestinal microbiota in high-fat diet-induced obesity in mice

Kusumoto, Y., Irie, J., Iwabu, K., Tagawa, H., Itoh, A., Kato, M., Kobayashi, N., Tanaka, K., Kikuchi, R., Fujita, M., Nakajima, Y., Morimoto, K., Sugizaki, T., Yamada, S., Kawai, T., Watanabe, M., Oike, Y. and Itoh, H.

Metabolism 71 1 - 6 2017年06月

ISSN 0026-0495

BACKGROUND: Bile acid binding resin (BAR) absorbs intestinal bile acids, and improves obesity and metabolic disorders, but the precise mechanism remains to be clarified. Recent findings reveal that obesity is associated with skewed intestinal microbiota. Thus, we investigated the effect of BAR on intestinal microbiota and the role of microbiota in the prevention of obesity in high-fat diet-induced obesity in mice. PROCEDURES: Male Balb/c mice were fed a low-fat diet (LFD), high-fat diet (HFD), or HFD with BAR (HFD+BAR), and then metabolic parameters, caecal microbiota, and metabolites were investigated. The same interventions were conducted in germ-free and antibiotic-treated mice. MAIN FINDINGS: The frequency of Clostridium leptum subgroup was higher in both HFD-fed and HFD+BAR-fed mice than in LFD-fed mice. The frequency of Bacteroides-Prevotella group was lower in HFD-fed mice than in LFD-fed mice, but the frequency was higher in HFD+BAR-fed mice than in HFD-fed mice. Caecal propionate was lower in HFD-fed mice than in LFD-fed mice, and higher in HFD+BAR-fed mice than in HFD-fed mice. HFD+BAR-fed mice showed lower adiposity than HFD-fed mice, and the reduction was not observed in germ-free or antibiotic-treated mice. Colonized germ-free mice showed a reduction in adiposity by BAR administration. Energy expenditure was lower in HFD-fed mice and higher in HFD+BAR-fed mice, but the increments induced by administration of BAR were not observed in antibiotic-treated mice. CONCLUSIONS: Modulation of intestinal microbiota by BAR could be a novel therapeutic approach for obesity.

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A case of familial dysalbuminemic hyperthyroxinemia (FDH) in Japan: FDH as a possible differential diagnosis of syndrome of inappropriate secretion of thyroid-stimulating hormone (SITSH)

Kobayashi, S., Yoshimura Noh, J., Shimizu, T., Sato, T., Kurihara, I., Sugino, K., Itoh, H. and Ito, K.

Endocr J 64 （ 2 ） 207 - 212 2017年02月

ISSN 0918-8959

Familial dysalbuminemic hyperthyroxinemia (FDH) is an autosomal dominant condition and is the most commonly inherited euthyroid hyperthyroxinemia in Caucasians. However, it is extremely rare in Asian populations. A 30-year-old Japanese woman, who was incidentally found to have apparent thyroid dysfunction, was admitted to our hospital in 2004. She had extremely elevated serum free thyroxine (FT4), moderately elevated free triiodothyronine (FT3), and normal thyroid-stimulating hormone (TSH). Clinical thyroid examination revealed no abnormalities other than small goiter. Anti-thyroglobulin antibody titer was positive, but titers of other anti-thyroid antibodies, including antithyroid peroxidase antibody, TSH receptor antibodies, and thyroid-stimulating antibody, were negative. Levels of FT3, FT4, and TSH were similar when measured by three different laboratory kits, and FT4 was still high when measured by equilibrium dialysis. By affinity chromatography, FT4, TT4, and albumin were extracted to the same fraction, and the levels of FT4 and TT4 were extremely high. By combination of reversed phase liquid chromatography and mass spectrometry techniques, the amino acid sequence of human serum albumin was determined. The patient was found to be a heterozygote for p.R218P mutation in the gene for human serum albumin and was diagnosed as FDH. This patient, who harbored the p.R218P mutation in the albumin gene, is the fifth case report of FDH in Japan. This condition is characterized by extremely high serum FT4 and moderately high serum FT3 levels. Although rare, FDH should be considered in the differential diagnosis for syndrome of inappropriate secretion of TSH (SITSH) in Japan.

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Temporal trends in renal function and birthweight in Japanese adolescent males (1998-2015)

Kanda T., Takeda A., Hirose H., Abe T., Urai H., Inokuchi M., Wakino S., Tokumura M., Itoh H., Kawabe H.

Nephrology Dialysis Transplantation （Nephrology Dialysis Transplantation） 33 （ 2 ） 304 - 310 2017年01月

ISSN 0931-0509

© 2017 The Author . Published by Oxford University Press on behalf of ERA-EDTA. Background Low birthweight (LBW) is a worldwide public health problem, demonstrating an increasing incidence in developed countries, including Japan. LBW is also a risk factor for later development of chronic kidney disease (CKD). To date, studies have not evaluated the population impacts of increasing LBW rates on renal function. Methods Estimated glomerular filtration rate (EGFR) was evaluated in 3737 Japanese adolescent males (15-16 years old) using annual cross-sectional data over an 18-year period (1998-2015). Results Between the initial (1998-2003) and final (2010-15) periods of the study, the mean birthweight decreased from 3213.4 ± 383.8 to 3116.2 ± 382.3 g and the LBW rate increased from 2.5 to 5.5% (both P ≤ 0.01). Additionally, the mean EGFR decreased from 105.1 ± 15.9 to 97.4 ± 13.8 mL/min/1.73 m 2 and the prevalence of mildly reduced renal function (EGFR ≤ 60-<90 mL/min/1.73 m 2) increased from 16.4 to 30.0% (both P ≤ 0.01), most evident in the LBW group (from 10.3 to 41.7%, P ≤0.01). The prevalence of proteinuria also increased significantly. Mildly reduced renal function was significantly associated with LBW [odds ratio (LBW 3000-3999 g) 1.51; 95% confidence interval 1.00-2.55; P = 0.047]. Conclusions In this population of Japanese adolescents, the frequency of mildly reduced renal function increased as the LBW frequency increased. Our findings may have implications for the broader Japanese population as well as for other populations in which the prevalence of LBW is increasing.

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A case of autoimmune polyendocrine syndrome type I with strong positive GAD antibody titer, followed up with glucose tolerance measured by oral glucose tolerance test

Murakami, R., Kawai, T., Meguro, S., Hayashi, M. and Itoh, H.

Neuro Endocrinol Lett 37 （ 8 ） 540 - 542 2017年01月

ISSN 0172-780X

A 26-year-old Japanese woman presented with adrenal insufficiency, and treatment was started with cortisone and fludrocortisone in 1975. A few years later, she presented with hypoparathyroidism and was diagnosed with autoimmune polyendocrine syndrome type I (APS I), and treatment with calcium and alfacalcidol was started. She was found to have subacute thyroiditis and relative adrenal failure in 2006. Her condition remained stable under treatment with cortisone, fludrocortisone, levothyroxine, calcium lactate, precipitated calcium carbonate and alfacalcidol. While antibodies against pancreatic glutamic acid decarboxylase (GAD) were strongly positive (7,690 U/ml), fasting glucose level was 4.9 mmol/L and HbA1c was 6.3% on admission. As GAD antibody showed a high-titer of >10,000 U/ml and fasting plasma glucose level showed a rising trend, we performed 75-g oral glucose tolerance test (OGTT) 6 years after discharge. Whereas OGTT in 2012 showed impaired glucose tolerance, glucose tolerance had reverted to normal in 2014. A patient with a high-titer GAD antibody does not always have progressive glucose intolerance. GAD antibody positivity is common in not only type 1 diabetes, but also APS I and stiff-person syndrome (SPS). There are differences in recognized epitopes among the three disorders. Epitopes for GAD65 antibody associated with type 1 diabetes are located in the middle region and the COOH-terminal of the GAD65 protein, whereas epitopes associated with SPS reside in the NH2-terminal in addition to the middle region and COOH-terminal. The present case suggests that these differences in epitopes may be related to various pathogenic mechanisms including glucose intolerance.

Ghrelin treatment improves physical decline in sarcopenia model mice through muscular enhancement and mitochondrial activation

Tamaki, M., Miyashita, K., Hagiwara, A., Wakino, S., Inoue, H., Fujii, K., Fujii, C., Endo, S., Uto, A., Mitsuishi, M., Sato, M., Doi, T. and Itoh, H.

Endocr J 64 （ Suppl. ） S47 - s51 2017年

ISSN 0918-8959

Chronic kidney disease (CKD) impairs physical performance in humans, which leads to a risk of all-cause mortality. In our previous study, we demonstrated that a reduction in muscle mitochondria rather than muscle mass was a major cause of physical decline in 5/6 nephrectomized CKD model mice. Because ghrelin administration has been reported to enhance oxygen utilization in skeletal muscle, we examined the usefulness of ghrelin for a recovery of physical decline in 5/6 nephrectomized C57Bl/6 mice, focusing on the epigenetic modification of peroxisome proliferator activated receptor gamma coactivator-1alpha (PGC-1alpha), a master regulator of mitochondrial biogenesis. The mice were intraperitoneally administered acylated ghrelin (0.1 nmol/gBW; three times per week) for a month. Muscle strength and exercise endurance were measured by using a dynamometer and treadmill, respectively. Mitochondrial DNA copy number was determined by quantitative PCR. The methylation levels of the cytosine residue at 260 base pairs upstream of the translation initiation point (C-260) of PGC-1alpha, which has been demonstrated to decrease the expression, was evaluated by methylation-specific PCR and bisulfite genomic sequencing methods after the ghrelin administration. Ghrelin administration improved both muscle strength and exercise endurance in the mice and was associated with an increase in muscle mass and muscle mitochondrial content. Ghrelin administration decreased the methylation ratio of C-260 of PGC-1alpha in the skeletal muscle and increased the expression. Therefore, ghrelin administration effectively reduced the physical decline in 5/6 nephrectomized mice and was accompanied with an increased mitochondrial content through de-methylation of the promoter region of PGC-1alpha in the muscle.

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Treatment of diabetic mice with the SGLT2 inhibitor TA-1887 antagonizes diabetic cachexia and decreases mortality

Sugizaki, T., Zhu, S., Guo, G., Matsumoto, A., Zhao, J., Endo, M., Horiguchi, H., Morinaga, J., Tian, Z., Kadomatsu, T., Miyata, K., Itoh, H. and Oike, Y.

NPJ Aging Mech Dis 3 12 2017年

ISSN 2056-3973

A favorable effect of an inhibitor of the sodium-glucose cotransporter 2 (SGLT2i) on mortality of diabetic patients was recently reported, although mechanisms underlying that effect remained unclear. Here, we examine SGLT2i effects on survival of diabetic mice and assess factors underlying these outcomes. To examine SGLT2i treatment effects in a model of severe diabetes, we fed genetically diabetic db/db mice a high-fat diet and then assessed outcomes including diabetic complications between SGLT2i TA-1887-treated and control mice. We also compare effects of SGLT2i TA-1887 with those of lowering blood glucose levels via insulin treatment. Untreated db/db mice showed remarkable weight loss, or cachexia, while TA-1887-treated mice did not but rather continued to gain weight at later time points and decreased mortality. TA-1887 treatment prevented pancreatic beta cell death, enhanced preservation of beta cell mass and endogenous insulin secretion, and increased insulin sensitivity. Moreover, TA-1887 treatment attenuated inflammation, oxidative stress, and cellular senescence, especially in visceral white adipose tissue, and antagonized endothelial dysfunction. Insulin treatment of db/db mice also prevented weight loss and antagonized inflammation and oxidative stress. However, insulin treatment had less potent effects on survival and prevention of cellular senescence and endothelial dysfunction than did TA-1887 treatment. SGLT2i treatment prevents diabetic cachexia and death by preserving function of beta cells and insulin target organs and attenuating complications. SGLT2i treatment may be a promising therapeutic strategy for type 2 diabetes patients with morbid obesity and severe insulin resistance.

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The short chain fatty acid receptor GPR43 regulates inflammatory signals in adipose tissue M2-type macrophages

Nakajima, A., Nakatani, A., Hasegawa, S., Irie, J., Ozawa, K., Tsujimoto, G., Suganami, T., Itoh, H. and Kimura, I.

PLoS One 12 （ 7 ） e0179696 2017年

ISSN 1932-6203

The regulation of inflammatory responses within adipose tissue by various types of immune cells is closely related to tissue homeostasis and progression of metabolic disorders such as obesity and type 2 diabetes. G-protein-coupled receptor 43 (GPR43), which is activated by short-chain fatty acids (SCFAs), is known to be most abundantly expressed in white adipose tissue and to modulate metabolic processes. Although GPR43 is also expressed in a wide variety of immune cells, whether and how GPR43 in adipose tissue immune cells regulates the inflammatory responses and metabolic homeostasis remains unknown. In this study, we investigated the role of GPR43 in adipose tissue macrophages by using Gpr43-deficient mice and transgenic mice with adipose-tissue-specific overexpression of GPR43. We found that GPR43 activation by SCFA resulted in induction of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) in anti-inflammatory M2-type macrophages within adipose tissue. By contrast, this effect was not noted in inflammatory M1-type macrophages, suggesting that GPR43 plays distinct functions depending on macrophage types. Local TNF-alpha signaling derived from steady-state adipose tissue is associated with proper tissue remodeling as well as suppression of fat accumulation. Thus, GPR43-involving mechanism that we have identified supports maintenance of adipose tissue homeostasis and increase in metabolic activity. This newly identified facet of GPR43 in macrophages may have clinical implications for immune-metabolism related episodes.

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L-Carnitine improves gastrointestinal disorders and altered the intestinal microbiota in hemodialysis patients

Irie, J., Kanno, Y., Kikuchi, R., Yoshida, T., Murai, S., Watanabe, M., Itoh, H. and Hayashi, M.

Biosci Microbiota Food Health 36 （ 1 ） 11 - 16 2017年

ISSN 2186-6953

Patients receiving hemodialysis also manifest gastrointestinal symptoms, such as constipation, caused by restriction of water intake and the loss of body water balance. Because dietary carnitine deficiency is considered to cause smooth muscle dysmotility of the gastrointestinal tract similarly to that in skeletal muscles, carnitine deficiency in hemodialysis patients may be one cause of gastrointestinal discomfort and dysfunctions. We performed a multicenter nonrandomized single-arm prospective clinical trial. Fifteen Japanese patients receiving hemodialysis were administered L-carnitine tablets (900 mg) for 3 months, and clinical and biochemical analyses were performed before and after treatment. The serum total carnitine level was increased significantly by supplementation with L-carnitine for 3 months (from 40.9 +/- 2.6 mumol/l to 172.3 +/- 19.0 mumol/l, p<0.05). The myasthenia score was decreased significantly by the supplementation (from 1.3 +/- 0.3 to 0.8 +/- 0.2, p<0.05). The frequency of passing stool tended to increase with the treatment for 3 months (from 4.2 +/- 0.5 times/week to 4.8 +/- 0.5 times/week). A phyla-level analysis of the microbiota showed that the composition of the individual microbiota was not different between before and after supplementation. A genus-level analysis, however, revealed that the relative abundance of genus Clostridium subcluster 4 was significantly decreased by the supplementation (from 7.7 +/- 1.9% to 4.7 +/- 1.3%, p<0.05). Oral supplementation of L-carnitine to the patients receiving hemodialysis improved not only their muscle discomfort but also their gastrointestinal disorders and microbiota, although its effect on the prognosis of hemodialysis patients should be further investigated.

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[Aging and homeostasis. Age-associated diseases and clinical application of NMN(Nicotinamide Mononucleotide).]

Irie, J. and Itoh, H.

Clin Calcium 27 （ 7 ） 983 - 990 2017年

ISSN 0917-5857

Sirtuins are NAD+-dependent deacetylase and have drawn much attention as important regulators of aging and longevity. Because NAD+ decline during the aging process, the approach to regulating aging using NAD+ precursor such as nicotinamide mononucleotide (NMN) to replenish cellular NAD+ through the activation of sirtuins have been investigated. In various animal models, NMN has been shown to mitigate age-associated physiological changes in liver, adipose tissue, muscle, pancreas, kidney, retina, and central nerve system. In animal models of metabolic diseases, NMN has been demonstrated to improve obesity, insulin resistance, and muscle mitochondrial dysfunction. In this review, recent findings in the NMN research will be summarized, and the potential of NMN on the regulation of age-associated diseases in humans will be discussed.

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Relationships between Composition of Major Fatty Acids and Fat Distribution and Insulin Resistance in Japanese

Fujii, C., Kawai, T., Azuma, K., Oguma, Y., Katsukawa, F., Hirose, H., Tanaka, K., Meguro, S., Matsumoto, H. and Itoh, H.

J Diabetes Res 2017 1567467 2017年

Objective. The aim of this study was to evaluate the relationships between the composition of free fatty acids (FFAs) and metabolic parameters, including body fat distribution, in Japanese. Methods. The study subjects were 111 Japanese patients (54 males, 57 females). Metabolic parameters and visceral and subcutaneous fat areas as determined by CT scanning at the umbilical level were measured. Glucose tolerance test (GTT) was performed by administering 75 g glucose orally. Results. The percentage of linoleic acid (C18:2), the greatest constituent among FFAs, was negatively correlated with visceral fat area (r = -0.411, p < 0.0001), fasting glucose (r = -0.330, p < 0.0001), HbA1c (r = -0.231, p = 0.0146), and systolic blood pressure (r = -0.224, p = 0.0184). Linoleic acid percentage was also significantly negatively correlated with HOMA-IR (r = -0.416, p < 0.0001) by simple correlation. Based on the findings of OGTT, the 111 subjects were classified into three groups: 33 with normal glucose tolerance, 71 with impaired glucose tolerance (IGT), and 7 diabetic subjects. The percentage of serum linoleic acid in diabetic subjects was significantly lower than that in normal subjects. Conclusion. We conclude that serum linoleic acid level is negatively correlated with the accumulation of visceral fat in relation to a reduction of insulin resistance in Japanese subjects.

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Generation of kidney tubular organoids from human pluripotent stem cells

Yamaguchi, S., Morizane, R., Homma, K., Monkawa, T., Suzuki, S., Fujii, S., Koda, M., Hiratsuka, K., Yamashita, M., Yoshida, T., Wakino, S., Hayashi, K., Sasaki, J., Hori, S. and Itoh, H.

Sci Rep 6 38353 2016年12月

ISSN 2045-2322

Recent advances in stem cell research have resulted in methods to generate kidney organoids from human pluripotent stem cells (hPSCs), which contain cells of multiple lineages including nephron epithelial cells. Methods to purify specific types of cells from differentiated hPSCs, however, have not been established well. For bioengineering, cell transplantation, and disease modeling, it would be useful to establish those methods to obtain pure populations of specific types of kidney cells. Here, we report a simple two-step differentiation protocol to generate kidney tubular organoids from hPSCs with direct purification of KSP (kidney specific protein)-positive cells using anti-KSP antibody. We first differentiated hPSCs into mesoderm cells using a glycogen synthase kinase-3beta inhibitor for 3 days, then cultured cells in renal epithelial growth medium to induce KSP+ cells. We purified KSP+ cells using flow cytometry with anti-KSP antibody, which exhibited characteristics of all segments of kidney tubular cells and cultured KSP+ cells in 3D Matrigel, which formed tubular organoids in vitro. The formation of tubular organoids by KSP+ cells induced the acquisition of functional kidney tubules. KSP+ cells also allowed for the generation of chimeric kidney cultures in which human cells self-assembled into 3D tubular structures in combination with mouse embryonic kidney cells.

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Nonalbuminuric Renal Insufficiency: Can It Be a Novel Category of Diabetic Nephropathy?

Tanaka, M. and Itoh, H.

Endocrinol Metab (Seoul) 31 （ 4 ） 533 - 534 2016年12月

ISSN 2093-596X

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Obesity-induced kidney injury is attenuated by amelioration of aberrant PHD2 activation in proximal tubules

Futatsugi, K., Tokuyama, H., Shibata, S., Naitoh, M., Kanda, T., Minakuchi, H., Yamaguchi, S., Hayashi, K., Minamishima, Y. A., Yanagita, M., Wakino, S. and Itoh, H.

Sci Rep 6 36533 2016年11月

ISSN 2045-2322

The involvement of tissue ischemia in obesity-induced kidney injury remains to be elucidated. Compared with low fat diet (LFD)-mice, high fat diet (HFD)-fed mice became obese with tubular enlargement, glomerulomegaly and peritubular capillary rarefaction, and exhibited both tubular and glomerular damages. In HFD-fed mice, despite the increase in renal pimonidazole-positive areas, the expressions of the hypoxia-responsive genes such as Prolyl-hydroxylase PHD2, a dominant oxygen sensor, and VEGFA were unchanged indicating impaired hypoxic response. Tamoxifen inducible proximal tubules (PT)-specific Phd2 knockout (Phd2-cKO) mice and their littermate control mice (Control) were created and fed HFD or LFD. Control mice on HFD (Control HFD) exhibited renal damages and renal ischemia with impaired hypoxic response compared with those on LFD. After tamoxifen treatment, HFD-fed knockout mice (Phd2-cKO HFD) had increased peritubular capillaries and the increased expressions of hypoxia responsive genes compared to Control HFD mice. Phd2-cKO HFD also exhibited the mitigation of tubular damages, albuminuria and glomerulomegaly. In human PT cells, the increased expressions of hypoxia-inducible genes in hypoxic condition were attenuated by free fatty acids. Thus, aberrant hypoxic responses due to dysfunction of PHD2 caused both glomerular and tubular damages in HFD-induced obese mice. Phd2-inactivation provides a novel strategy against obesity-induced kidney injury.

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Corrigendum to "Placental (pro)renin receptor expression and plasma soluble (pro)renin receptor levels in preeclampsia" [YPLAC 37C (2016) 72-78]

Nartita, T., Ichihara, A., Matsuoka, K., Takai, Y., Bokuda, K., Morimoto, S., Itoh, H. and Seki, H.

Placenta 47 130 2016年11月

ISSN 0143-4004

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The role of short-chain fatty acid on blood pressure regulation

Miyamoto, J., Kasubuchi, M., Nakajima, A., Irie, J., Itoh, H. and Kimura, I.

Curr Opin Nephrol Hypertens 25 （ 5 ） 379 - 83 2016年09月

ISSN 1062-4821

PURPOSE OF REVIEW: The gut microbiota and its metabolites have been implicated in the regulation of host physiological functions such as inflammatory and metabolic responses. The short-chain fatty acid (SCFA) receptor is expressed in the kidney and blood vessels as well, and has been reported to function as a regulator of blood pressure (BP). This review highlights the role of SCFAs derived from gut microbial fermentation in the regulation of BP. RECENT FINDINGS: Olfactory receptor 78 (Olfr78) is a member of the G-protein-coupled receptor family, and it plays a key role as a chemosensor in various tissues. Both Olfr78 and G protein-coupled receptor 41 (GPR41) are expressed in smooth muscle cells of blood vessels and they recognize SCFAs. Oral administration of SCFAs was found to change BP in vivo, an effect that was altered in Olfr78 and GPR41-deficient mice. SUMMARY: The regulation of BP via SCFA receptors has provided new insights into the interactions between the gut microbiota and BP control systems. We summarize these interactions and describe their contributions to a novel pathway involved in BP regulation. These recent findings could open new avenues for the development of therapeutic strategies for the treatment of cardiovascular diseases.

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Colonic Pro-inflammatory Macrophages Cause Insulin Resistance in an Intestinal Ccl2/Ccr2-Dependent Manner

Kawano, Y., Nakae, J., Watanabe, N., Kikuchi, T., Tateya, S., Tamori, Y., Kaneko, M., Abe, T., Onodera, M. and Itoh, H.

Cell Metab 24 （ 2 ） 295 - 310 2016年08月

ISSN 1550-4131

High-fat diet (HFD) induces low-grade chronic inflammation and insulin resistance. However, little is known about the mechanism underlying HFD-induced chronic inflammation in peripheral insulin-responsive tissues. Here, we show that colonic pro-inflammatory macrophages regulate insulin sensitivity under HFD conditions. To investigate the pathophysiological role of colonic macrophages, we generated macrophage-specific chemokine (C-C Motif) receptor 2 (Ccr2) knockout (M-Ccr2KO) and intestinal epithelial cell-specific tamoxifen-inducible Ccl2 knockout (Vil-Ccl2KO) mice. Both strains exhibited similar body weight to control under HFD. However, they exhibited decreased infiltration of colonic pro-inflammatory macrophages, decreased intestinal permeability, and inactivation of the colonic inflammasome. Interestingly, they showed significantly improved glucose tolerance and insulin sensitivity with decreased chronic inflammation of adipose tissue. Therefore, inhibition of pro-inflammatory macrophage infiltration prevents HFD-induced insulin resistance and could be a novel therapeutic approach for type 2 diabetes.

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Dysbiosis in the Pathophysiology of Coronary Artery Disease

Irie, J. and Itoh, H.

J Atheroscler Thromb 23 （ 8 ） 901 - 2 2016年08月

ISSN 1340-3478

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Rationale and Design of the Standard Versus Intensive Statin Therapy for Hypercholesterolemic Patients with Diabetic Retinopathy (EMPATHY) Study: a Randomized Controlled Trial

Ueshima, K., Itoh, H., Kanazawa, N., Komuro, I., Nagai, R., Takeuchi, M. and Yamazaki, T.

J Atheroscler Thromb 23 （ 8 ） 976 - 90 2016年08月

ISSN 1340-3478

AIM: Hyperlipidemia and diabetic retinopathy increase the risk of cardiovascular disease (CVD). The standard versus intEnsive statin therapy for hypercholesteroleMic Patients with diAbetic retinopaTHY (EMPATHY) study examines whether intensive lipid-lowering therapy is superior to standard therapy in reducing the incidence of cardiovascular events in patients with hyperlipidemia and diabetic retinopathy, but without a history of coronary artery disease. METHODS: Patients who had elevated low-density lipoprotein cholesterol (LDL-C) and diabetic retinopathy without a history of coronary artery disease were eligible for the study. Patients were randomly assigned in a 1:1 ratio to receive intensive or standard therapy. Patients are being treated with monotherapy with 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor (statin) for a maximum of 5.5 years to achieve the following LDL-C target: 70 mg/dL for the intensive therapy group or >/=100 and 120 mg/dL for the standard therapy group. The primary endpoint is a composite of incidence of CVD and death from CVD. RESULTS: Between May 2010 and October 2013, 5,995 patients were assessed for eligibility, and 5,144 were assigned to the study treatment (2,571 and 2,573 in the intensive and standard therapy groups, respectively), and baseline data were analyzed from 5,107 (2,550 in the intensive therapy group and 2,557 in the standard therapy group). CONCLUSIONS: This is the first study assessing the benefits of intensive statin therapy in patients with hypercholesterolemia and diabetic retinopathy in a primary prevention setting. Furthermore, this study evaluates the appropriateness of the treat-to-target approach because all patients are treated to achieve specific LDL-C targets by titrating statin therapy. CLINICAL TRIAL REGISTRATION NUMBER: UMIN000003486.

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Effects of Obesity and Diabetes on alpha- and beta-Cell Mass in Surgically Resected Human Pancreas

Inaishi, J., Saisho, Y., Sato, S., Kou, K., Murakami, R., Watanabe, Y., Kitago, M., Kitagawa, Y., Yamada, T. and Itoh, H.

J Clin Endocrinol Metab 101 （ 7 ） 2874 - 82 2016年07月

ISSN 0021-972

CONTEXT: The ethnic difference in beta-cell regenerative capacity in response to obesity may be attributable to different phenotypes of type 2 diabetes among ethnicities. OBJECTIVE: This study aimed to clarify the effects of diabetes and obesity on beta- (BCM) and alpha-cell mass (ACM) in the Japanese population. DESIGN, SETTING, AND PARTICIPANTS: We obtained the pancreases of 99 individuals who underwent pancreatic surgery and whose resected pancreas sample contained adequate normal pancreas for histological analysis. Questionnaires on a family history of diabetes and history of obesity were conducted in 59 patients. Pancreatic sections were stained for insulin or glucagon, and fractional beta- and alpha-cell area were measured. Islet size and density as well as beta-cell turnover were also quantified. RESULTS: In patients with diabetes, BCM was decreased by 46% compared with age- and body mass index-matched nondiabetic patients (1.48% +/- 1.08% vs 0.80% +/- 0.54%, P < .001), whereas there was no difference in ACM between the groups. There was no effect of obesity or history of obesity on BCM and ACM irrespective of the presence or absence of diabetes. There was a negative correlation between BCM, but not ACM, and glycated hemoglobin before and after pancreatic surgery. In addition, reduced BCM was observed in patients with pancreatic cancer compared with those with other pancreatic tumors. CONCLUSIONS: These findings suggest that the increase in BCM in the face of insulin resistance is extremely limited in the Japanese, and BCM rather than ACM has a major role in regulating blood glucose level in humans.

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