Clinical significance of differences between home and clinic systolic blood pressure readings in patients with hypertension

Objectives

To elucidate the clinical significance of differences between home- and clinic-measured systolic blood pressure (SBP) in patients with treated hypertension, and to assess the correlations between SBPs and arterial stiffness.

Methods

Patients with treated hypertension measured their blood pressure (BP) themselves once, at home, in the morning (<1 h after awakening) using an automated oscillometric sphygmomanometer. Clinic BP was measured once, at an outpatient clinic on the same day, using a similar instrument. Arterial stiffness was measured by cardio–ankle vascular index (CAVI). Differences between home and clinic SBPs, and the correlations between CAVI and home SBP, clinic SBP, and the difference between home and clinic SBPs, were analysed.

Results

Seventy-six patients with treated hypertension (mean age, 71 years) were evaluated. There was no statistically significant difference between home and clinic SBP (mean ± SD 132 ± 14 and 133 ± 16 mmHg, respectively). Home SBP showed no correlation with CAVI, whereas clinic SBP showed a weak correlation. The difference between the home and clinic SBP showed a stronger correlation with CAVI, and was statistically significant.

Conclusions

The difference between home- and clinic-measured SBP showed a better correlation with arterial stiffness than did either home or clinic SBP alone.

Association between left ventricular hypertrophy and changes in arterial stiffness during hypertensive treatment

Cardio-ankle vascular index (CAVI) has been demonstrated as a parameter of arterial stiffness, which antihypertensive therapy may improve. However, little information is available about the factors affecting changes in arterial stiffness assessed by CAVI during antihypertensive therapy. We performed a study to examine the factors affecting changes in arterial stiffness assessed by CAVI during antihypertensive therapy. Eighty treated hypertensive patients (71 ± 10 years) were divided into two groups: 50 patients showing a decrease in CAVI (Group 1) and 30 patients showing an increase (Group 2) during observation (24 ± 11 months) of antihypertensive therapy. The groups did not differ in the rates of use of angiotensin II receptor blockers or calcium channel blockers. Age (Group 1: 67 ± 11 versus Group 2: 74 ± 8 years), left ventricular mass index (LVMI) (Group 1: 103 ± 19 versus Group 2: 120 ± 24 g/m(2)) and systolic blood pressure (Group 1: 133 ± 17 versus Group 2: 144 ± 23 mm Hg) at the start of observation were significantly higher in Group 2 than in Group 1 (p = 0.003, p = 0.001 and p = 0.027, respectively). The changes in CAVI during observation were correlated only with LVMI (r = 0.289, p = 0.009) at the start of observation for all 80 patients. It may be difficult to improve arterial stiffness assessed by CAVI during antihypertensive therapy in hypertensive patients with left ventricular hypertrophy.

Apoptosis and autophagy contribute to gender difference in cardiac ischemia-reperfusion induced injury in rats

AIMS

Gender difference in cardiac ischemia-reperfusion (IR) induced injury has been reported in animal models. However, a large-scale clinical trial found an increase in cardiovascular incidents in women with hormone replacement therapy. The present study is aimed to explore possible mechanisms of gender difference in cardiac IR induced injury.

MAIN METHODS

Male and female Sprague-Dawley rats were subjected to a 30-min coronary arterial occlusion followed by reperfusion. The infarct size and apoptotic cell number at 24h after reperfusion were significantly lower in female rats than in male rats.

KEY FINDINGS

Male rats expressed higher anti-apoptotic protein Bcl2 levels compared with female rats under physiological conditions. However, levels of Bcl2 were reduced significantly after IR in male rats but not in, female rats. Levels of pro-apoptotic protein, Bax and phospho-p38, showed similar under physiological conditions. In response to IR expression of Bax was markedly reduced in female rats but not in male rats, and expression of phospho-p38 was significantly increased in male rats but not in female rats. In addition, female rats showed marked increase of autophagy marker, ratio of LC3B to LC3A, while male rats significantly decreased the ratio in response to IR.

SIGNIFICANCE

Gender difference in IR injury is due to the different regulation of anti-apoptotic protein, pro-apoptotic protein and autophagy protein levels in male rats and levels in female rats. Our results provide better understanding of sex differences in cardiac IR injury.

Bowen disease of the palm associated with human papillomavirus 52

Human papillomavirus (HPV) is a well-known risk factor for many human cancers, especially cervical cancers. Among the nonmelanoma skin cancers, Bowen disease (BD) of the genitalia and fingers has also been shown to be closely associated with the high-risk types of HPV, especially HPV16. We report a case of BD of the palm, which is a very rare location for BD. In addition to its rare location, HPV52, which is classified as a mucous high-risk HPV type, was detected in the lesion by PCR restriction fragment length polymorphism analysis. To our knowledge, this is the first reported case of BD associated with HPV52.

Chronic restraint stress inhibits hair growth via substance P mediated by reactive oxygen species in mice

Backgrounds

Solid evidence has demonstrated that psychoemotional stress induced alteration of hair cycle through neuropeptide substance P (SP) mediated immune response, the role of reactive oxygen species (ROS) in brain-skin-axis regulation system remains unknown.

Objectives

The present study aims to investigate possible mechanisms of ROS in regulation of SP-mast cell signal pathway in chronic restraint stress (CRS, a model of chronic psychoemotional stress) which induced abnormal of hair cycle.

Methods and Results

Our results have demonstrated that CRS actually altered hair cycle by inhibiting hair follicle growth in vivo, prolonging the telogen stage and delaying subsequent anagen and catagen stage. Up-regulation of SP protein expression in cutaneous peripheral nerve fibers and activation of mast cell were observed accompanied with increase of lipid peroxidation levels and reduction of the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in CRS mice skin. In addition, SP receptor antagonist (RP67580) reduced mast cell activations and lipid peroxidation levels as well as increased GSH-Px activity and normalized hair cycle. Furthermore, antioxidant Tempol (a free radical scavenger) also restored hair cycle, reduced SP protein expression and mast cell activation.

Conclusions

Our study provides the first solid evidence for how ROS play a role in regulation of psychoemotional stress induced SP-Mast cell pathway which may provide a convincing rationale for antioxidant application in clinical treatment with psychological stress induced hair loss.

Relationship between arterial stiffness and variability in systolic blood pressure during a single clinic visit in patients with hypertension

Objective

To examine factors affecting systolic blood pressure (SBP) variability during a single clinic visit, in treated hypertensive patients.

Methods

Hypertensive patients were recruited to this observational study. Blood pressure was measured using an automated blood pressure monitor when each patient arrived at the outpatient clinic and again when they saw the physician. Mean SBP and SBP variability during a single clinic visit were calculated. The cardio–ankle vascular index (CAVI), as a marker of arterial stiffness, was also measured.

Results

A total of 57 treated hypertensive patients (mean age 71 years) were included in the study. The mean SBP was positively correlated with age ( r = 0.457), while SBP variability was positively correlated with age ( r = 0.383), CAVI ( r = 0.330), and glycosylated haemoglobin ( r = 0.345) and triglyceride levels (r = 0.299).

Conclusion

Variability in SBP during a single clinic visit showed better correlations with arterial stiffness and risk factors for atherosclerosis than did mean SBP. Large SBP variability during a single clinic visit may reflect progression of atherosclerosis, in treated hypertensive patients.

Antitumor effect of metformin in esophageal cancer: in vitro study

Recent studies suggest that metformin, which is a member of the biguanide family and commonly used as an oral anti-hyperglycemic agent, may reduce cancer risk and improve prognosis of numerous types of cancer. However, the mechanisms underlying the antitumor effect of metformin on esophageal cancer remain unknown. The goal of the present study was to evaluate the effects of metformin on the proliferation of human ESCC in vitro, and to study changes in the expression profile of microRNAs (miRNAs), since miRNAs have previously been associated with the antitumor effects of metformin in other human cancers. The human ESCC cell lines T.T, KYSE30 and KYSE70 were used to study the effects of metformin on human ESCC in vitro. In addition, we used miRNA array tips to explore the differences between miRNAs in KYSE30 cells with and without metformin treatment. Metformin inhibited the proliferation of T.T, KYSE30 and KYSE70 cells in vitro. Metformin blocked the cell cycle in G0/G1 in vitro. This blockade was accompanied by a strong decrease of G1 cyclins, especially cyclin D1, as well as decreases in cyclin-dependent kinase (Cdk)4, Cdk6 and phosphorylated retinoblastoma protein (Rb). In addition, the expression of miRNAs was markedly altered with the treatment of metformin in vitro. Metformin inhibited the growth of three ESCC cell lines, and this inhibition may have involved reductions in cyclin D1, Cdk4 and Cdk6.

Association of serum anti-periodontal pathogen antibody with ischemic stroke

BACKGROUND

Periodontitis increases the risk of atherosclerotic cardiovascular disease and ischemic stroke. In this study, we evaluated whether serum antibody levels against individual periodontal pathogens are significantly associated with ischemic stroke subtypes and their risk factors.

METHODS

Patients with acute ischemic stroke (n = 132; 74 male and 58 female, 71.3 ± 10.7 years) and patients with no previous stroke (n = 77; 38 male and 39 female, 70.7 ± 9.5 years) were consecutively enrolled in this study. Stroke subtype was evaluated based on the Trial of Org 10172 in Acute Stroke Treatment classification. Serum was obtained from each patient after obtaining their consent to participate in the study. The levels of serum antibodies against Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Prevotella intermedia (Pi) were evaluated by ELISA. Serum high-sensitivity C-reactive protein (hs-CRP) levels were measured by nephelometry.

RESULTS

Serum hs-CRP levels were significantly associated with acute ischemic stroke even after controlling for acute ischemic stroke, hypertension, diabetes mellitus and bulb/ internal carotid artery (ICA) atherosclerosis which were statistically selected (coefficient 0.245, 95% CI 0.142-0.347, p < 0.0001). The serum-antibody level of Pi was significantly higher in atherothrombotic-stroke patients than in patients with no previous stroke (p = 0.0035). Detectable serum anti-Pg antibody was significantly associated with atrial fibrillation (overall χ(2) = 35.5, R(2) = 0.18, n = 209, p < 0.0001; anti-Pg antibody: OR 4.36, 95% CI 1.71-12.10, p = 0.0017), and detectable serum anti-Pi antibody was significantly associated with bulb/ICA atherosclerosis after controlling for the statistically selected associated factors (overall χ(2) = 46.1, R(2) = 0.18, n = 209, p < 0.0001; anti-Pg antibody: OR 16.58, 95% CI 3.96-78.93, p < 0.0001). The levels of serum anti-Pi antibody were significantly associated with atherothrombotic stroke with the statistically selected associated factors excluding bulb/ICA atherosclerosis (overall χ(2) = 77.0, R(2) = 0.44, n = 129, p < 0.0001; anti-Pi antibody: OR 23.6, 95% CI 2.65-298.2, p = 0.008). However, when we included bulb/ICA atherosclerosis in this model, the levels of serum anti-Pi antibody were no longer significantly associated with atherothrombotic stroke (overall χ(2) = 98.0, R(2) = 0.56, n = 129, p < 0.0001; anti-Pi antibody: p = 0.107).

CONCLUSIONS

Our results suggest that anti-Pg antibody is associated with atrial fibrillation and that anti-Pi antibody is associated with carotid artery atherosclerosis. In addition, anti-Pi antibody may be associated with atherothrombotic stroke through its association with carotid artery atherosclerosis. Thus, periodontitis may lead to serious systemic diseases.

Human microRNAs originated from two periods at accelerated rates in mammalian evolution

MicroRNAs (miRNAs) are short, noncoding RNAs that modulate genes posttranscriptionally. Frequent gains and losses of miRNA genes have been reported to occur during evolution. However, little is known systematically about the periods of evolutionary origin of the present miRNA gene repertoire of an extant mammalian species. Thus, in this study, we estimated the evolutionary periods during which each of 1,433 present human miRNA genes originated within 15 periods, from human to platypus-human common ancestral branch and a class "conserved beyond theria," primarily using multiple genome alignments of 38 species, plus the pairwise genome alignments of five species. The results showed two peak periods in which the human miRNA genes originated at significantly accelerated rates. The most accelerated rate appeared in the period of the initial phase of hominoid lineage, and the second appeared shortly before Laurasiatherian divergence. Approximately 53% of the present human miRNA genes have originated within the simian lineage to human. In particular, approximately 28% originated within the hominoid lineage. The early phase of placental mammal radiation comprises approximately 28%, while no more than 15% of human miRNAs have been conserved beyond placental mammals. We also clearly showed a general trend, in which the miRNA expression level decreases as the miRNA becomes younger. Intriguingly, amid this decreasing trend of expression, we found one significant rise in the expression level that corresponded to the initial phase of the hominoid lineage, suggesting that increased functional acquisitions of miRNAs originated at this particular period.

[HDL metabolism in lifestyle-related illnesses]

Coronary artery disease (CAD) is a major public heath burden in many countries. HDL plays a critical role in cholesterol metabolism, so called reverse cholesterol transport (RCT). In RTC, HDL particles shuttle cholesterol from extra-hepatic tissues to the liver for excretion. Thus, enhanced RCT lowers total body cholesterol and thereby reduces the risk of developing CAD. We reported that human homologue of scavenger receptor of the class BI/CLA-1 (hSR-BI/CLA-1), like mouse SR-BI, functioned as a receptor for HDL. Hepatic hSR-BI/CLA-1 stimulates RCT, because it increases the hepatic uptake of free cholesterol from HDL. ABCA1 is a pivotal regulator of lipid efflux from cells to HDL particles, and plays an important role in RCT. Hyperglycemia is one of the risk factors for atherosclerosis. We showed that high glucose inactivated RCT via the inhibition of both hSR-BI/CLA-1 and ABCA1 expression. On the other hand, recent studies demonstrated that HDL binding to SR-BI activates eNOS, with the generation of nitric oxide, which may contribute to the positive cardiovascular effects. Treatment with angiotensin II reduced HDL-HDL-dependent eNOS activation via hSR-BI/CLA-1 expression, resulting in the progression of atherosclerosis. In conclusion, we demonstrate some mechanisms by which HDL is atheroprotective.

Association between oxidative stress assessed by urinary 8-hydroxydeoxyguanosine and the cardiac function in hypertensive patients without overt heart disease

Although increased oxidative stress is known to be associated with worsened cardiac function in chronic heart failure, consensus is still lacking regarding the association between oxidative stress and cardiac function in hypertensive patients without overt heart disease. This study aimed to evaluate the association between oxidative stress assessed by urinary 8-hydroxydeoxyguanosine (8-OHdG) and cardiac function in hypertensive patients without overt heart disease. We enrolled a total of 80 hypertensive patients (70 ± 11 y) who had been taking antihypertensive medications for at least 1 year. Urinary 8-OHdG levels were measured by an immunochromatographic assay (ICR-001, Selista Inc., Tokyo, Japan). Echocardiography was performed to assess the left ventricular (LV) diastolic function by measuring early diastolic mitral annular velocity (e') and the ratio of early transmitral flow velocity (E) to e' (E/e'). Urinary 8-OHdG was correlated with E/e' (r = 0.346, P = .002), e' (r = -0.310, P = .005), and HbA1c (r = 0.276, P = .013). Multiple linear regression analysis revealed that only e' (β = -0.343, P = .004) was an independent determinant of urinary 8-OHdG. In conclusion, decreased e' is independently associated with elevated urinary 8-OHdG, a marker of oxidative stress, in hypertensive patients. Therefore, an elevated urinary 8-OHdG level may be useful in detecting subclinical LV diastolic dysfunction in hypertensive patients without overt heart disease.

Liver X receptor α is involved in the transcriptional regulation of the 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase gene

The activity of 6-phosphofructo-1-kinase is strictly controlled by fructose-2,6-bisphosphate, the level of which is regulated by another enzyme, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK2/FBP2). PFK2/FBP2 is a bifunctional enzyme, having kinase and phosphatase activities, and regulates both glycolysis and gluconeogenesis. Here, we examined the hormonal regulation of the PFK2/FBP2 gene in vitro using the reporter assay, the electromobility shift assay (EMSA), and the chromatin immunoprecipitation (ChIP) assay in HuH7 cells and also using the mouse liver in vivo. We found that the transcriptional activity of the PFK2/FBP2 gene was stimulated by insulin and inhibited by cAMP and glucocorticoid. Liver X receptor (LXR) α showed a potent and specific stimulatory effect on PFK2/FBP2 gene transcription. Deletion and mutagenesis analyses identified the LXR response element (LXRE) in the 5'-promoter region of the PFK2/FBP2 gene. Binding of LXRα was confirmed by the EMSA and ChIP assay. Endogenous PFK2/FBP2 mRNA in the mouse liver was increased in the fasting/refeeding state compared with the fasting state. Altogether, PFK2/FBP2 gene transcription is found to be regulated in a way that is more similar to other glycolytic enzyme genes than to gluconeogenic genes. Furthermore, our data strongly suggest that LXRα is one of the key regulators of PFK2/FBP2 gene transcription.

Xanthogranuloma of the intrasellar region presenting in pituitary dysfunction: a case report

Introduction

Differentiation of cystic mass lesions of the sellar and parasellar regions may pose a diagnostic dilemma for physicians, neurosurgeons, radiologists and pathologists involved in treating patients with these entities. A considerable number of tumors previously identified as craniopharyngiomas may, in fact, have been xanthogranulomas. We report a case of pituitary dysfunction caused by xanthogranuloma of the intrasellar region.

Case presentation

A 47-year-old man of Japanese descent presented to our institution with a tumor located exclusively in the intrasellar region which manifested as severe hypopituitarism. MRI revealed a clearly defined intrasellar mass that was heterogeneously hyperintense on T1-weighted images and markedly hypointense on T2-weighted images. We preoperatively diagnosed the patient with Rathke's cleft cyst or non-functioning pituitary adenoma. Although the tumor was completely removed using a transsphenoidal approach, the improvement of the patient's endocrine function was marginal, and continued endocrine replacement therapy was needed. Postoperatively, a histological examination revealed the tumor to be a xanthogranuloma of the intrasellar region. His visual field defects and headache improved.

Conclusion

Because diagnosis depends on surgical intervention and xanthogranulomas of the intrasellar region are very rare, the natural history of xanthogranuloma is still unknown. Therefore, this entity is difficult to diagnose preoperatively. We suggest that xanthogranuloma should be included in the differential diagnosis, even in the case of sellar lesions, to formulate appropriate postoperative management and improve endocrine outcomes.

Association between urinary 8-hydroxydeoxyguanosine, an indicator of oxidative stress, and the cardio-ankle vascular index in hypertensive patients

AIMS

Oxidative stress has been recently postulated to be an important factor in the pathogenesis and development of arteriosclerosis. Although urinary 8-hydroxydeoxyguanosine (8-OHdG) is clinically used as a marker of oxidative stress, its usefulness in diagnosing arteriosclerosis has not been fully examined. This study aimed to evaluate the association between urinary 8-OHdG and the cardioankle vascular index (CAVI) as a marker of arterial stiffness in hypertensive patients.

METHODS

We enrolled 100 hypertensive patients (70 ± 10 years) who had been taking antihypertensive medications for at least one year. Urinary 8-OHdG levels were measured by an immunochromatographic assay (ICR-001; Selista Inc., Tokyo, Japan). CAVIs were measured at the same visit.

RESULTS

Urinary 8-OHdG was correlated with smoking habits (r=0.382, p<0.001) and CAVIs (r= 0.223, p= 0.026). Multiple linear regression analysis revealed two independent determinants of urinary 8-OHdG: smoking habits (β=0.501, p<0.001) and CAVI (β=0.325, p=0.001). In addition, CAVIs were correlated with age (r= 0.600, p<0.001), BMI (r=-0.348, p<0.001), systolic blood pressure (r= 0.343, p<0.001), pulse pressure (r= 0.358, p<0.001), serum creatinine level (r=0.408, p<0.001), urinary 8-OHdG level (r= 0.223, p= 0.026), and diabetes (r= 0.210, p=0.036). Multiple linear regression analysis revealed two independent determinants of CAVI: age (β= 0.568, p<0.001) and 8-OHdG (β=0.357, p<0.001).

CONCLUSION

Elevated CAVI is independently associated with an elevated urinary 8-OHdG level in hypertensive patients.

The optimal timing of antihypertensive medication administration for morning hypertension in patients with cerebral infarction

Morning hypertension is an independent risk factor for cardiovascular diseases, particularly stroke. However, the optimal time at which to take antihypertensive medication to treat morning hypertension remains unclear. We prospectively enrolled elderly patients (over 65 years old) with morning hypertension who had suffered an ischemic stroke (or strokes). Additional treatments (one of six arms) were randomly administered for 10 weeks in the morning, in the evening or at bedtime (n=15 for each time point/medication). The patients measured their blood pressure and heart rate at home for 14 days prior to the intervention and for the final 14 days, and recorded the data in a blood pressure diary. The patients' urinary albumin/creatinine ratios were evaluated before and after the 10-week intervention. A total of 270 patients were enrolled in this study (mean age: 75.6±5.8 years; female/male ratio: 125/145). Their morning and evening systolic blood pressures were significantly decreased after following any of the study medication dosing schedules (P<0.001). However, the reductions in the differences between the morning and evening systolic blood pressures were significant only when the medication was taken in the evening or at bedtime (P<0.001 with repeated measures analysis of variance). Furthermore, the recovery rate from morning hypertension was also higher when the medication was taken in the evening (40.0%) or at bedtime (45.6%), rather than in the morning (22.2%; P=0.003 with the χ(2)-test). Antihypertensive medication taken in the evening or at bedtime is the most effective in treating morning hypertension when the patient adheres to the medication regimen.

Association between Cardiac Function and Pulmonary Function in Hypertensive Patients

OBJECTIVE: This study examined the association between cardiac function and pulmonary function in hypertensive patients. METHODS: Hypertensive patients without overt cardiovascular disease were enrolled ( n = 43; mean ± SD age 71 ± 9 years). Pulmonary function was measured by the percentage of predicted forced vital capacity (%FVC) and the ratio of 1 s forced expiratory volume (FEV1) to FVC (FEV1/FVC ratio). Left ventricular ejection fraction (LVEF) and the ratio of peak early diastolic transmitral flow (E) to peak early diastolic mitral annular velocity (e′) (E/e′ ratio) were assessed using echocardiography. RESULTS: Multiple linear regression analysis revealed that E/e′ was independently associated with %FVC and that LVEF was independently associated with FEV1/FVC ratio. Both LVEF and FEV1/FVC ratio were significantly lower in hypertensive former or current smokers than in hypertensive never smokers. CONCLUSIONS: Subclinical cardiac dysfunction was independently associated with reduced pulmonary function in hypertensive patients. Hypertensive patients with decreased pulmonary function may need preventive care to prevent the progression of heart failure.

The antidiabetic drug metformin inhibits gastric cancer cell proliferation in vitro and in vivo

Recent studies suggest that metformin, which is commonly used as an oral anti-hyperglycemic agent of the biguanide family, may reduce cancer risk and improve prognosis, but the mechanisms by which metformin affects various cancers, including gastric cancer, remains unknown. The goal of the present study was to evaluate the effects of metformin on human gastric cancer cell proliferation in vitro and in vivo and to study microRNAs (miRNA) associated with antitumor effect of metformin. We used MKN1, MKN45, and MKN74 human gastric cancer cell lines to study the effects of metformin on human gastric cancer cells. Athymic nude mice bearing xenograft tumors were treated with or without metformin. Tumor growth was recorded after 4 weeks, and the expression of cell-cycle-related proteins was determined. In addition, we used miRNA array tips to explore the differences among miRNAs in MKN74 cells bearing xenograft tumors treated with or without metformin in vitro and in vivo. Metformin inhibited the proliferation of MKN1, MKN45, and MKN74 in vitro. Metformin blocked the cell cycle in G(0)-G(1)in vitro and in vivo. This blockade was accompanied by a strong decrease of G(1) cyclins, especially in cyclin D1, cyclin-dependent kinase (Cdk) 4, Cdk6 and by a decrease in retinoblastoma protein (Rb) phosphorylation. In addition, metformin reduced the phosphorylation of epidermal growth factor receptor and insulin-like growth factor-1 receptor in vitro and in vivo. The miRNA expression was markedly altered with the treatment of metformin in vitro and in vivo. Various miRNAs altered by metformin also may contribute to tumor growth in vitro and in vivo.

Raloxifene inhibits menin-dependent estrogen receptor activation in breast cancer cells

BACKGROUND

Menin is a tumor suppressor encoded by Men1 that is mutated in the human-inherited tumor syndrome--multiple endocrine neoplasia type 1. Menin binds to estrogen receptors (ER) to enhance estrogen activity in breast cancer cells.

AIM

Our clinical study showed that the outcome in the case of menin-positive tumors was worse than in the case of menin-negative tumors. We examined the role of raloxifene on the cell growth in a menin-positive breast cancer cell line.

MATERIAL AND METHODS

To examine the mechanism of raloxifene on menin-dependent activation of ER, we employed the mammalian two-hybrid system. We have established a breast cancer cell line that stably expresses menin. Using these cells, we have examined the effect of raloxifene and tamoxifen on cell growth of menin-transfected cells.

RESULTS

The expression of activation function (AF)-2 enhanced menin-mediated luciferase expression in the mammalian two-hybrid assay. Raloxifene attenuated the effect of menin on estrogen response element-luciferase activation, indicating that raloxifene inhibited the binding of menin to AF-2. Raloxifene significantly inhibited the growth of menin-transfected cells in a dose-dependent manner. Tamoxifen also inhibited menin-transfected MCF-7 cells; however, this inhibition was much less than that of raloxifene.

CONCLUSION

Raloxifene inhibits the binding of menin to the AF-2 domain of ERα, suggesting that raloxifene is one of the therapeutic options for menin-positive breast cancer.

Association of cardio-ankle vascular index with brain natriuretic peptide levels in hypertension

AIMS

Plasma brain natriuteric peptide (BNP) is an established marker of cardiovascular events in individuals without heart failure. Although the cardio-ankle vascular index (CAVI) is clinically used as a parameter of arterial stiffness, its usefulness for predicting cardiovascular events has not been fully examined. This study aimed to evaluate the association among CAVIs, plasma BNP levels and left ventricular (LV) hypertrophy and dysfunction in hypertensive patients.

METHODS

We enrolled 136 hypertensive patients (69±10 years) who had been taking antihypertensive medications for at least one year. Echocardiography was performed to evaluate LV hypertrophy and function. Plasma BNP levels and CAVIs were also measured simultaneously.

RESULTS

CAVI was correlated with plasma BNP (r =0.245, p =0.004). Multiple linear regression analysis revealed three independent determinants of CAVI: age (β =0.568, p <0.001), diameter of ascending aorta (β =0.289, p <0.001), and diabetes (β =0.207, p =0.003). In addition, multiple linear regression analysis revealed two independent determinants of the plasma BNP level: left atrial diameter (β =0.334, p <0.001) and CAVI (β =0.256, p =0.002).

CONCLUSION

The present study indicates that increased CAVI is independently associated with elevated plasma BNP produced by increased LV afterload, that is, arterial stiffness, in hypertensive patients. Moreover, the present study raises the possibility that CAVI may be as useful as the plasma BNP level for predicting the risk of cardiovascular events in hypertensive patients.

Aortic root dilatation as a marker of subclinical left ventricular diastolic dysfunction in patients with cardiovascular risk factors

Consensus is lacking about the clinical importance of aortic root dilatation in assessment of the risk of cardiovascular disease. In this study, correlations between aortic root diameter and echocardiographic features of left ventricular (LV) diastolic function were investigated in 333 patients with at least one cardiovascular risk factor (hypertension, diabetes or dyslipidaemia) and preserved LV systolic function. Aortic root diameter was measured by M-mode echocardiography, and LV diastolic function was evaluated by measuring the peak velocity of early (E) and late (A) diastolic transmitral blood flow and peak early diastolic mitral annular velocity (E') by Doppler echocardiography. Linear regression analysis showed that, in men, age was not related to aortic root diameter but hypertension and LV hypertrophy were, whereas the converse was true in women. The parameters E, E/A ratio and E', were related to aortic root diameter in both sexes. Stepwise multiple regression analysis confirmed that E in women and E' in men were independently associated with aortic root diameter. It is concluded that aortic root dilatation might be a useful marker of subclinical LV diastolic dysfunction. Patients with preserved systolic function showing aortic root dilatation should, therefore, be given preventative therapy against LV diastolic heart failure.

Reduced bone mineral density in hypertensive patients is associated with left ventricular diastolic dysfunction, not left ventricular hypertrophy

Left ventricular (LV) hypertrophy and diastolic dysfunction are commonly observed in hypertensive patients, and have been demonstrated to be risk factors of chronic heart failure due to LV diastolic dysfunction. Recently, reduced bone mineral density has been found in hypertensive patients compared with healthy controls. However, relationships between bone mineral density and LV hypertrophy and diastolic dysfunction have not been fully assessed. We examined relationships between bone mineral density and both LV hypertrophy and diastolic dysfunction in 38 hypertensive patients (23 males, 15 females; mean age 71 ± 8 y) who had been treated with antihypertensive drugs for at least 1 year. The bone mineral density of the calcaneus was measured with a quantitative ultrasound measurement device (A-1000 EXPRESS/InSight, GE Healthcare, Horten, Norway), and the stiffness index was determined as a parameter of bone mineral density. Echocardiography was performed to measure the left ventricular mass index as a parameter of LV hypertrophy. Left ventricular diastolic dysfunction was also assessed by early diastolic mitral annular velocity (e'), and the ratio of early transmitral flow velocity (E) to e' (E/e'). The bone mineral density did not correlate with left ventricular mass index, but did correlate with e' (r = 0.453, P < .01) and E/e' (r = -0.359, P < .05). Thus, reduced bone mineral density in hypertensive patients is not associated with LV hypertrophy but with LV diastolic dysfunction. Hypertensive patients with reduced bone mineral density may have a high risk of chronic heart failure due to LV diastolic dysfunction as well as bone fractures due to osteoporosis.

Exendin-4 regulates the expression of the ATP-binding cassette transporter A1 via transcriptional factor PREB in the pancreatic β cell line

BACKGROUND

PRL regulatory element-binding (PREB) protein is a transcription factor that regulates insulin promoter activity in the rat anterior pituitary. The PREB protein is expressed not only in the anterior pituitary but also in pancreatic β cells. Previously, we have reported that PREB plays an important role in glucose-mediated insulin gene expression in pancreatic β cells. The ATP-binding cassette transporter A1 (ABCA1) in pancreatic β cells influences insulin secretion and glucose homeostasis. Exendin-4 (Ex-4), a longacting agonist of the glucagon-like peptide 1, stimulates ABCA1 expression in pancreatic β cells.

AIMS

In this study, we examined the role played by PREB in Ex-4-induced ABCA1 expression in pancreatic β cells.

MATERIAL/SUBJECTS AND METHODS

PREB mRNA and protein expression were evaluated in pancreatic β cell line (INS-1 cells) treated with Ex-4 (10 nM).

RESULTS

Ex-4 stimulated PREB protein and mRNA expression in INS-1 cells. PREB stimulated the activity of the luciferase reporter protein that was under the control of the ABCA1 promoter. Chromatin immunoprecipitation assay showed that PREB mediates its transcriptional activity by directly binding to the ABCA1 promoter region. Finally, we used small interfering RNA to inhibit PREB expression in the cells and demonstrated that the knockdown of PREB expression attenuated the effects of Ex-4 on ABCA1 expression.

CONCLUSION

PREB mediates Ex-4-stimulated transcription of the ABCA1 gene in pancreatic β cells.