Role of alginate in the mechanism by which brown seaweed Saccharina japonica intake alleviates an increase in blood pressure in 2-kidney, 1-clip renovascular hypertensive rats.

BACKGROUND: The intake of Saccharina japonica (SJ), a widely consumed brown seaweed, has been reported to decrease blood pressure (BP) in hypertensive rats. It has been suggested that this effect is related to an increase in fecal sodium excretion (SE) by alginate (Alg) to the gastrointestinal tract; however, the mechanism is still unclear. This study investigated how different seaweeds with different amounts of Alg suppressed BP increase and enhanced fecal SE in 2-kidney, 1-clip renovascular hypertensive (2K1C) rats given SJ diet. METHODS: Rats with 2K1C or sham operation were fed a normal-/high-salt diet with some kinds of seaweeds (5.0%, w/w) or SJ extract with different Alg contents for 6 weeks. We measured systolic BP every week and mean arterial pressure at the end, and measured the total and molecular weights of Alg in each seaweed. Then, we evaluated the relationship of the Alg amount in each seaweed with the suppression of BP increase in 2K1C rats. Finally, urinary and fecal SE for 24 h was measured. RESULTS: The intake of SJ, SJ extract, Saccharina ochotensis (SO) blades and SO roots suppressed BP increase in 2K1C rats, but the strength was not proportional to the amounts of Alg contained in the seaweeds. Although SJ intake increased fecal SE in 2K1C rats fed a high-salt diet, the fecal SE was much less than urinary SE. CONCLUSION: The sodium excretion in feces by Alg in SJ may not be one of the major mechanisms by which SJ intake attenuates hypertension in 2K1C rats.

White matter alterations in the dorsal attention network contribute to a high risk of unsafe driving in healthy older people.

Aim: Healthy older drivers may be at high risk of fatal traffic accidents. Our recent study showed that volumetric alterations in gray matter in the brain regions within the dorsal attention network (DAN) were strongly related to the risk of unsafe driving in healthy older people. However, the relationship between white matter (WM) structural connectivity and driving ability in healthy older people is still unclear. Methods: We used diffusion tensor imaging to examine the association between microstructural alterations in the DAN and the risk of unsafe driving among healthy older people. We enrolled 32 healthy older individuals aged over 65 years and screened unsafe drivers using an on-road driving test. We then determined the pattern of WM aberrations in unsafe drivers using tract-based spatial statistics. Results: The analysis demonstrated that unsafe drivers had significantly higher axial diffusivity values in nine WM clusters compared with safe drivers. These results were primarily observed bilaterally in the dorsal superior longitudinal fasciculus, which is involved in the DAN. Furthermore, correlation analyses showed that higher axial diffusivity values in the superior longitudinal fasciculus were associated with lower Trail Making Test A scores within unsafe drivers. This result suggests that functionally, WM microstructural alterations in the DAN are associated with attention problems, which may contribute to the risk of unsafe driving among healthy older people. Conclusion: Our findings may elucidate the neurobiological mechanisms underlying the increased risk of unsafe driving in healthy older people, potentially facilitating the development of new interventions to prevent fatal accidents.

Regional Gray Matter Volume Identifies High Risk of Unsafe Driving in Healthy Older People.

In developed countries, the number of traffic accidents caused by older drivers is increasing. Approximately half of the older drivers who cause fatal accidents are cognitively normal. Thus, it is important to identify older drivers who are cognitively normal but at high risk of causing fatal traffic accidents. However, no standardized method for assessing the driving ability of older drivers has been established. We aimed to establish an objective assessment of driving ability and to clarify the neural basis of unsafe driving in healthy older people. We enrolled 32 healthy older individuals aged over 65 years and classified unsafe drivers using an on-road driving test. We then utilized a machine learning approach to distinguish unsafe drivers from safe drivers based on clinical features and gray matter volume data. Twenty-one participants were classified as safe drivers and 11 participants as unsafe drivers. A linear support vector machine classifier successfully distinguished unsafe drivers from safe drivers with 87.5% accuracy (sensitivity of 63.6% and specificity of 100%). Five parameters (age and gray matter volume in four cortical regions, including the left superior part of the precentral sulcus, the left sulcus intermedius primus [of Jensen], the right orbital part of the inferior frontal gyrus, and the right superior frontal sulcus), were consistently selected as features for the final classification model. Our findings indicate that the cortical regions implicated in voluntary orienting of attention, decision making, and working memory may constitute the essential neural basis of driving behavior.

Development of an invasive ductal carcinoma in a contralateral composite nipple graft after an autologous breast reconstruction: a case report.

BACKGROUND: Nipple-areola complex (NAC) reconstruction is a technique used in breast reconstructive surgery, which is performed during the final stage of breast reconstruction after total mastectomy of primary breast cancer. Composite nipple grafts utilizing the contralateral NAC are common; however, to our knowledge, there are no reports of new primary invasive ductal carcinoma development within the graft. Here, we describe one such case for the first time. CASE PRESENTATION: A 54-year-old woman was referred to us by the Department of Plastic and Reconstructive Surgery in our medical center for further evaluation of right nipple erosion. She had undergone total mastectomy of the right breast following a breast cancer diagnosis 15 years ago, at which time tumor biological profiling revealed the following: estrogen receptor (ER), positive; progesterone receptor (PgR), negative; and human epidermal growth factor receptor 2 (HER2), undetermined. She received adjuvant chemotherapy and endocrine therapy. She defaulted endocrine therapy for a few years, and 7 years after surgery, she underwent autologous breast reconstruction with a deep inferior epigastric perforator (DIEP) flap. In the following year, NAC reconstruction was performed using a composite graft technique. Seven years after the NAC reconstruction, erosion appeared on the nipple grafted from its contralateral counterpart; scrape cytology revealed malignancy. The skin on the right side of her chest around the NAC and subcutaneous fat tissue consisted of transferred tissue from the abdomen, as the DIEP flap and grafted nipple were located on the graft skin. The right nipple carcinoma arose from the tissue taken from the left nipple. Magnetic resonance imaging (MRI) or computed tomography showed no malignant findings in the left breast. As the malignant lesion seemed limited to the area around the grafted right nipple on MRI, surgical resection with sufficient lateral and deep margins was performed around the right nipple. Pathological findings revealed invasive ductal carcinoma with comedo ductal components infiltrating the graft skin and underlying adipose tissue. Immunohistochemistry revealed positive for ER, PgR, and HER2. CONCLUSIONS: To our knowledge, this is the first case involving the development of invasive ductal carcinoma in a nipple graft constructed on the skin of a DIEP flap, with the origin from the contralateral breast's nipple.

Synthesis and preliminary evaluation of neoglycopolymers carrying multivalent N-glycopeptide units.

In the present study, for the discovery of uncharacterized glycan-binding receptors or lectin-like receptors in plants, we developed neoglycopolymers to which three types of N-glycopeptides are conjugated; the first with plant complex type N-glycan (M3FX), the second with high-mannose type N-glycan (M8), and the third with animal complex type N-glycan (NeuAc2Gal2GN2M3). Three types of Asn-oligosaccharide (Asn-M3FX, Asn-M8, or Asn-NeuAc2Gal2GN2M3) were prepared from storage glycoproteins of Ginkgo biloba seeds, Vigna angularis seeds, and egg yolk glycopeptides from actinase digests of each glycoproteins or glycopeptide. Neoglycopolymers were synthesized such that the α-amino groups of Asn-oligosaccharide were coupled to the carboxyl groups of poly-γ-L-glutamic acid (γ-L-PGA) with 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride n-hydrate (DMT-MM). The resulting neoglycopolymers were purified through a combination of gel-filtration and reverse-phase HPLC. The incorporation of N-glycans into γ-L-PGA (mol%) was estimated through amino acid composition analysis after acid hydrolysis. The incorporation rates of Asn-M3FX, Asn-M8, and Asn-NeuAc2Gal2GN2M3 into γ-L-PGA were 15.4%, 8.6%, and 11.1%, indicating that nearly 890, 500, and 640 molecules of N-glycans were conjugated with γ-L-PGA, respectively. Furthermore, we confirmed that the neoglycopolymer carrying the multivalent high-mannose type N-glycans is a useful tool for rapid purification of mannose-binding protein, Concanavalin A, from jack bean extract.

Convenient preparation of an antigenic oligosaccharide from white kidney bean powder: A useful plant oligosaccharide for synthesis of immunoactive glycopolymer.

Plant glycoproteins, especially allergenic glycoproteins such as pollen allergens, often carry antigenic N-glycans with α1-3 fucose and/or ß1-2 xylose residue(s) on the trimannosyl core structure. We previously reported that one of such antigenic free-form N-glycans, Man3Xyl1Fuc1GlcNAc2 (M3FX) suppressed IL-4 production from Th2 cells of pollinosis patients. For the molecular-level analysis of this immunoactivity, an effective and convenient procedure for large scale preparation of the immunoactive free-form N-glycan and a synthesis of glycopolymers bearing multivalent M3FX has been required. During the preparation of prebiotic oligosaccharides from several edible beans, we found that the free-form M3FX accumulates in relatively large amounts in white kidney beans. In this report, we describe a new procedure for preparation of M3FX from white kidney bean powders by a combination of ion-exchange method, gel-filtration, and hydrophilic partitioning. The high-purity of M3FX prepared by this procedure was confirmed by MS-analysis and 1H-NMR, suggesting that the free-form M3FX can be used for the synthesis of neoglycopolymer. Using this new procedure, the immunoactive oligosaccharide can be prepared without the chemical method such as hydrazinolysis and other purification steps required to exclude other type of N-glycans.

Myoepithelioma-like tumor of the vulvar region showing infiltrative growth and harboring only a few estrogen receptor-positive cells: A case report.

Recently, a new entity "myoepithelioma-like tumor of the vulvar region (MELTVR)" was proposed as a rare mesenchymal neoplasm arising in vulvar regions of adult women. While MELTVRs morphologically resemble soft tissue myoepitheliomas and extraskeletal myxoid chondrosarcomas, they have a unique immunohistochemical profile (positive for epithelial membrane antigen and estrogen receptor, negative for S100 protein and glial fibrillary acidic protein, and loss of INI1/SMARCB1 expression), and lack EWSR1 and NR4A3 gene rearrangement, as seen by fluorescence in situ hybridization. MELTVRs are usually well-demarcated tumors, with no reports of extensive infiltrative growth. In the current report, we present an unusual case of MELTVR showing infiltrative growth and harboring only a few estrogen receptor-positive cells, which might indicate a variation in this rare tumor.

Acquired resistance to everolimus in aromatase inhibitor-resistant breast cancer.

We previously reported the establishment of several types of long-term estrogen-depleted-resistant (EDR) cell lines from MCF-7 breast cancer cells. Type 1 EDR cells exhibited the best-studied mechanism of aromatase inhibitor (AI) resistance, in which estrogen receptor (ER) expression remained positive and PI3K signaling was upregulated. Type 2 EDR cells showed reduced ER activity and upregulated JNK-related signaling. The mTOR inhibitor everolimus reduced growth in cells similar to Type 1 EDR cells. The present study generated everolimus-resistant (EvR) cells from Types 1 and 2 EDR cells following long-term exposure to everolimus in vitro. These EvR cells modeled resistance to AI and everolimus combination therapies following first-line AI treatment failure. In Type 1 EvR cells, everolimus resistance was dependent on MAPK signaling; single agents were not effective, but hormonal therapy combined with a kinase inhibitor effectively reduced cell growth. In Type 2 EvR cells, ER expression remained negative and a JNK inhibitor was ineffective, but a Src inhibitor reduced cell growth. The mechanism of acquired everolimus resistance appears to vary depending on the mechanism of AI resistance. Strategies targeting resistant tumors should be tailored based on the resistance mechanisms, as these mechanisms impact therapeutic efficacy.

Repetitive patterns in rapid optical variations in the nearby black-hole binary V404 Cygni.

How black holes accrete surrounding matter is a fundamental yet unsolved question in astrophysics. It is generally believed that matter is absorbed into black holes via accretion disks, the state of which depends primarily on the mass-accretion rate. When this rate approaches the critical rate (the Eddington limit), thermal instability is supposed to occur in the inner disk, causing repetitive patterns of large-amplitude X-ray variability (oscillations) on timescales of minutes to hours. In fact, such oscillations have been observed only in sources with a high mass-accretion rate, such as GRS 1915+105 (refs 2, 3). These large-amplitude, relatively slow timescale, phenomena are thought to have physical origins distinct from those of X-ray or optical variations with small amplitudes and fast timescales (less than about 10 seconds) often observed in other black-hole binaries-for example, XTE J1118+480 (ref. 4) and GX 339-4 (ref. 5). Here we report an extensive multi-colour optical photometric data set of V404 Cygni, an X-ray transient source containing a black hole of nine solar masses (and a companion star) at a distance of 2.4 kiloparsecs (ref. 8). Our data show that optical oscillations on timescales of 100 seconds to 2.5 hours can occur at mass-accretion rates more than ten times lower than previously thought. This suggests that the accretion rate is not the critical parameter for inducing inner-disk instabilities. Instead, we propose that a long orbital period is a key condition for these large-amplitude oscillations, because the outer part of the large disk in binaries with long orbital periods will have surface densities too low to maintain sustained mass accretion to the inner part of the disk. The lack of sustained accretion--not the actual rate--would then be the critical factor causing large-amplitude oscillations in long-period systems.

Mechanisms of hormonal therapy resistance in breast cancer.

Whilst estrogen receptor (ER)-positive breast cancers are preferentially treated with hormone therapy, approximately one-third of them relapse. The mechanisms of refractoriness have been investigated by numerous studies but have not been fully clarified. Hormonal therapy resistance, particularly aromatase inhibitor (AI) resistance, may be related to the acquisition of alternative intracellular ER signaling. We have been investing the mechanisms using cancer specimens and cell lines by monitoring the transcription activity of ERs. AI refractory specimens showed diverse ER activity in the adenovirus estrogen receptor element-green fluorescent protein (ERE-GFP) assay and varied sensitivity to anti-estrogens, indicating the existence of multiple resistant mechanisms. We established six different types of cell lines mimicking AI resistance from ERE-GFP-introduced ER-positive cell lines. They revealed that multiple and alternative ER activating pathways were involved in the resistance, such as phosphorylation-dependent or androgen metabolite-dependent mechanisms. The response to fulvestrant and mammalian target of rapamycin inhibitor also varied among individual resistant cell lines. These results indicate that further subclassification of ER-positive breast cancer is extremely important to decide the therapeutic management of not only hormonal therapy but also new molecular target therapy.

Large-scale preparation of glycopeptides harboring the TF-antigen unit from royal jelly.

We have reported that new N-glycans carrying the TF-antigen occurred on a major royal jelly glycoprotein, and we have identified the glycosylation site to which the antigenic N-glycan is linked, but an appropriate procedure has not been established to prepare non-labeled immunoreactive glycopeptides in large amounts for functional analysis. In this study, we developed an effective method of preparing Asn-glycopeptide bearing TF-antigen.

Effect of geometry and microstructure of honeycomb TCP scaffolds on bone regeneration.

In recent years, artificial biological materials have been commonly used for the treatment of bone tissue defects caused by trauma, tumors, or surgical stress. Although tricalcium phosphate (TCP) is a promising absorbent bone tissue reconstruction biomaterial, it has been reported that its biocompatibility and osteoconductivity depend on its preparation method and sintering temperature. In addition, although it is thought that the microenvironment produced by the extracellular matrix plays an important role in cell growth and differentiation, there have been few studies on how the geometric structure of artificial biological materials affects cells. In the present study, a new honeycomb TCP scaffold containing through-holes with diameters of 300 µm has been developed. The influence of the sintering temperature on the crystal structure and material properties of the honeycomb TCP scaffold was investigated using scanning electron microscopy and X-ray diffraction. Its biocompatibility and osteoconductivity were also evaluated by implantation into experimental animals. It was found that a ß-TCP scaffold sintered at 1200°C exhibited high biocompatibility and osteoconductivity, and when it was loaded with BMP-2, it exhibited both osteoconductivity and osteoinductivity, promoting rapid bone formation in both ectopic and orthotopic areas. It is thus a highly promising bone reconstruction material that is expected to find clinical applications.

Large-scale preparation of Asn-glycopeptide carrying structurally homologous antigenic N-glycan.

In our previous report (M. Okano, et al., Clin. Exp. Allergy, 34, 770-778 (2004)), we found that free plant complex type N-glycans suppressed the production of IL4 from Th2 cells of Japanese cedar pollinosis patients, suggesting that plant complex type N-glycan can be used as a leading compound for developing immuno-pharmaceuticals. Although immunoreactive plant complex type N-glycans occur ubiquitously on glycoproteins expressed in plants, an appropriate procedure has not been established to prepare non-labeled immunoreactive glycans or glycopeptides bearing structurally homologous immunoreactive glycans in large amounts. In this study, therefore, we developed a new preparative procedure for the large-scale preparation of Asn-glycopeptide bearing plant complex type N-glycan using a combination of gel-filtration and the hydrophilic partitioning method. By this new method, about 103 mg of Asn-glycopeptide bearing the antigenic N-glycans was obtained from 1.9 kg of shelled Ginkgo biloba seeds.

Periodontal regeneration following application of basic fibroblast growth factor-2 in combination with beta tricalcium phosphate in class III furcation defects in dogs.

The aim of this study was to investigate the effect of tunnel structured ß-tricalcium phosphate (ß-TCP) on the regenerative potential of basic fibroblast growth factor-2 (bFGF-2) in class III furcation defects in dogs. The furcations of 30 mandibular premolar teeth received: 1) 0.3% bFGF-2 solution in conjunction with ß-TCP; 2) 0.3% bFGF-2 solution; and 3) no implant material (Control group). The dogs were sacrificed 8 weeks post-surgery, and healing was evaluated histologically. New bone formation was significantly greater in the bFGF-2/ß-TCP group compared to the bFGF-2 solution and Control groups (p<0.01). New cementum formation in the bFGF-2/ß-TCP and bFGF-2 solution groups was significantly greater than that in the Control group (p<0.01). These findings suggested that bFGF-2 alone enhances connective tissue attachment in a manner similar to the combination of bFGF-2 and ß-TCP. Furthermore, this combination enhances bone formation up to the fornix in class III furcation defects.

High expression of ATP-binding cassette transporter ABCC11 in breast tumors is associated with aggressive subtypes and low disease-free survival.

ATP-binding cassette (ABC) transporters are membrane proteins that efflux various compounds from cells, including chemotherapeutic agents, and are known to affect multidrug resistance. Recent reports disagree on whether ABCC11 is a risk factor for breast tumorigenesis, but its expression in breast cancer is poorly investigated. We hypothesized that both frequency and expression levels of ABC transporters in breast tumors would vary by cancer subtype, and be associated with prognosis. Here, we constructed a tissue microarray breast tumor samples from 281 patients, and analyzed expressions of ABCB1, ABCC1, ABCC11, and ABCG2 immunohistochemically. Breast cancer subtypes were determined by immunohistochemistry of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2). Protein expression was correlated to clinicopathological characteristics, clinical follow-up, and pathological complete response to neoadjuvant chemotherapy. The tissue microarray comprised 191 luminal A (68.0 %), 17 luminal B (6.0 %), 27 HER2 (9.6 %), and 46 triple-negative (16.4 %) samples. ABCC1 and ABCC11 expressions were associated with significantly shorter disease-free survival (P = 0.027 and P = 0.003, respectively). ABCC1, ABCC11, and ABCG2, but not ABCB1, were expressed significantly more, and more frequently, in aggressive subtypes. Patients with HER2+ and triple-negative tumor subtypes that expressed high levels of ABCC11 had significantly worse disease-free survival (P = 0.017 and P < 0.001, respectively). We have shown, for the first time, that ABCC1, ABCC11, and ABCG2 are highly expressed in aggressive breast cancer subtypes, and that tumor ABCC11 expression is associated with poor prognosis.

The molecular evolution of the pif family proteins in various species of mollusks.

Various novel proteins have been identified from many kinds of mollusk shells. Although such matrix proteins are believed to play important roles in the calcium carbonate crystal formation of shells, no common proteins that interact with calcium carbonate or that are involved in the molecular mechanisms behind shell formation have been identified. Pif consists of two proteins, Pif 80 and Pif 97, which are encoded by a single mRNA. Pif 80 was identified as a key acidic protein that regulates the formation of the nacreous layer in Pinctada fucata, while Pif 97 has von Willebrand factor type A (VWA) and chitin-binding domains. In this study, we identified Pif homologues from Pinctada margaritifera, Pinctada maxima, Pteria penguin, Mytilus galloprovincialis, and in the genome database of Lottia gigantea in order to compare their primary protein sequences. The VWA and chitin-binding domains are conserved in all Pif 97 homologues, whereas the amino acid sequences of the Pif 80 regions differ markedly among the species. Sequence alignment revealed the presence of a novel significantly conserved sequence between the chitin-binding domain and the C-terminus of Pif 97. Further examination of the Pif 80 regions suggested that they share a sequence that is similar to the laminin G domain. These results indicate that all Pif molecules in bivalves and gastropods may be derived from a common ancestral gene. These comparisons may shed light on the correlation between molecular evolution and morphology in mollusk shell microstructure.

Impacts and predictors of cytotoxic anticancer agents in different breast cancer subtypes.

Breast cancer is not a single entity. This study therefore aimed to identify differences in the impacts of anticancer agents and predictive factors between different breast cancer subtypes. A total of 234 patients with luminal (n = 109), luminal-HER2 (L-H, n = 29), HER-2 (n = 35), or triple negative (TN, n = 61) breast cancer subtypes were treated with standard neoadjuvant chemotherapy consisting of an anthracycline and/or taxane. Pathological response and prognosis were examined in each subtype. Expression levels of estrogen and progesterone receptors, HER-2, nuclear grade, MIB-1, p53, topoisomerase IIalpha (topoIIalpha), cytokeratin (CK) 5/6, and epidermal growth factor receptor (EGFR) were examined in association with quasipathological complete response (QpCR). QpCR rates were 9.1% (10/109) in luminal, 45% (13/29) in L-H, 37% (13/35) in HER2, and 54.1% (33/61) in TN. Non-QpCR patients showed significantly poorer 3-year disease-free survival than QpCR patients in TN, but not in patients with other subtypes. No factors were associated with QpCR in luminal patients. Patients with higher nuclear grade were more likely to achieve QpCR in L-H. The proliferative markers MIB-1 and topoIlalpha had opposite impacts on pathological response in HER-2 and TN. The QpCR rate was significantly higher in TN lacking CK5/6 and/or EGFR expression, defined as nonbasal subtype, compared with basal subtype (p = 0.049). Cytotoxic anticancer agents were associated with different responses in different breast cancer subtypes. Identifying basal-type cancer and further subdivision of nonbasal types is important for treating TN patients.

Structural features of N-glycans of seaweed glycoproteins: predominant occurrence of high-mannose type N-glycans in marine plants.

We analyzed structural features of N-glycans linked to glycoproteins expressed in various seaweeds to identify new sources of biologically-important N-glycans or N-glycopeptides. Structural analysis of the N-glycans of glycopeptides prepared from pepsin digests of 15 species of seaweed revealed that only high-mannose type N-glycans occur in seaweed glycoproteins, and the Man9GlcNAc2 structure predominates in Sargassum fulvellum and Zostera marina, while no typical plant complex type N-glycans bearing ß1-2 xylosyl and α1-3 fucosyl residues present in either algae or seagrass. These results indicate that seaweeds lack the activities of several of the glycosyltransferases required for the biosynthesis of the complex type N-glycans found in terrestrial plants, and that the context of N-glycan processing in seaweeds is different from that in terrestrial plant cells.

Periodontal repair following implantation of beta-tricalcium phosphate with different pore structures in Class III furcation defects in dogs.

The aim of this study was to investigate the effect of the pore characteristics of ß-tricalcium phosphate (ß-TCP) on periodontal healing in class III furcation defects in dogs. Two types of ß-TCP were prepared for grafting; 1) a tunnel pipe structure with an inner diameter of 300 µm, and 2) continuous pore structure with interconnected macropores. The furcations of thirty mandibular premolar teeth were implanted with each type of ß-TCP or were left untreated as control. The dogs were sacrificed 8 weeks post-surgery, and healing was evaluated histologically. Downgrowth of junctional epithelium in the tunnel structure group was significantly less than that in the other two groups (p<0.01). There was significantly more new bone formation and new cementum formation in the tunnel structure group than that in the other two groups (p<0.01). These findings suggested that ß-TCP with a tunnel pipe structure promotes periodontal healing in class III furcation defects.

Heart angiotensin II-induced cardiomyocyte hypertrophy suppresses coronary angiogenesis and progresses diabetic cardiomyopathy.

To examine whether and how heart ANG II influences the coordination between cardiomyocyte hypertrophy and coronary angiogenesis and contributes to the pathogenesis of diabetic cardiomyopathy, we used Spontaneously Diabetic Torii (SDT) rats treated without and with olmesartan medoxomil (an ANG II receptor blocker). In SDT rats, left ventricular (LV) ANG II, but not circulating ANG II, increased at 8 and 16 wk after diabetes onset. SDT rats developed LV hypertrophy and diastolic dysfunction at 8 wk, followed by LV systolic dysfunction at 16 wk, without hypertension. The SDT rat LV exhibited cardiomyocyte hypertrophy and increased hypoxia-inducible factor-1α expression at 8 wk and to a greater degree at 16 wk and interstitial fibrosis at 16 wk only. In SDT rats, coronary angiogenesis increased with enhanced capillary proliferation and upregulation of the angiogenic factor VEGF at 8 wk but decreased VEGF with enhanced capillary apoptosis and suppressed capillary proliferation despite the upregulation of VEGF at 16 wk. In SDT rats, the phosphorylation of VEGF receptor-2 increased at 8 wk alone, whereas the expression of the antiangiogenic factor thrombospondin-1 increased at 16 wk alone. All these events, except for hyperglycemia or blood pressure, were reversed by olmesartan medoxomil. These results suggest that LV ANG II in SDT rats at 8 and 16 wk induces cardiomyocyte hypertrophy without affecting hyperglycemia or blood pressure, which promotes and suppresses coronary angiogenesis, respectively, via VEGF and thrombospondin-1 produced from hypertrophied cardiomyocytes under chronic hypoxia. Thrombospondin-1 may play an important role in the progression of diabetic cardiomyopathy in this model.