Atrial Fibrillation in Primary Aldosteronism

Primary aldosteronism (PA) is the most common cause of secondary hypertension. Increasing evidence has demonstrated an increased cardiovascular risk in patients with PA compared to those with essential hypertension (EH), including atrial fibrillation (AF), the most prevalent arrhythmia among adults that is associated with an elevated risk of subsequent cerebro-cardiovascular adverse events. The mechanisms of increased prevalence of AF in PA patients are complex. Excessive aldosterone production is regarded to be a key component in the pathogenesis of AF, in addition to arterial hypertension and electrolyte imbalance. In addition, several translational and clinical studies have reported that structural remodeling with atrial fibrosis and electrical remodeling with arrhythmogenicity induced by an excess of aldosterone also play major roles in AF genesis. Clinical studies from several registries and meta-analysis have reported an increased prevalence and risk of AF in PA patients compared to EH patients. Recent trials have further demonstrated a reduction in the risk of new-onset atrial fibrillation (NOAF) after adrenalectomy, while the results of medical treatment with mineralocorticoid receptor antagonists (MRAs) have been inconsistent. This review outlines the current evidence of the relationship between PA and AF, and highlights recent progress in the management of PA with regards to the development of AF.

Influence of Different Treatment Strategies on New-Onset Atrial Fibrillation Among Patients With Primary Aldosteronism: A Nationwide Longitudinal Cohort-Based Study

Background Primary aldosteronism (PA) is associated with higher atrial fibrillation prevalence and other cardiovascular complications. However, the effect of target treatment to prevent new-onset atrial fibrillation (NOAF) remains unclear. This study investigated incidence of NOAF under different treatment strategies in patients with PA. Methods and Results We analyzed longitudinal data for patients with PA without atrial fibrillation history from 1997 to 2009 within the National Health Insurance Research Database in Taiwan. Patients with essential hypertension matched by propensity score were enrolled as controls. The primary outcome measurement was NOAF, and secondary outcome measurements were mortality, major cardiac and cardiac/cerebrovascular events, and a combined end point of NOAF and mortality. We identified 2202 patients with PA (534 adrenalectomy, 1668 mineralocorticoid receptor antagonist [MRA] therapy) and 8808 essential hypertension controls with mean follow-up of 4.4 years. In primary outcome measurement, patients with PA who underwent adrenalectomy had a lower incidence of NOAF (adjusted hazard ratio; 0.28, P=0.011) than controls. In contrast, the patients with PA who received MRA therapy had comparable risk of NOAF (adjusted hazard ratio, 1.20; P=0.224). In secondary outcome measurement, patients with PA who underwent adrenalectomy had a lower rate of mortality and combined end point of NOAF and mortality than controls. Patients with PA who received MRA therapy had a higher risk of mortality, major cardiac and cardiac/cerebrovascular events, and combined NOAF with mortality than the essential hypertension controls. Conclusions Compared with patients with essential hypertension, patients with PA who underwent adrenalectomy had a lower incidence of NOAF. However, this finding was not observed in patients with PA who received MRA therapy with a lower dose. Differences between the 2 strategies may reduce with a higher dose of MRA therapy.

[Expression of HLA-DP in patients with neuromyelitis optica spectrum disorders]

Objective: To investigate the effect of HLA-DP gene expression on the susceptibility and disease status of neuromyelitis optica spectrum disorders (NMOSD). Methods: A total of 86 NMOSD patients (52 in acute phase and 34 in remission phase), 52 multiple sclerosis (MS) patients (20 in acute phase and 32 in remission phase) diagnosed in Department of Neurology, the Third Affiliated Hospital of Sun Yat-sen University and 29 healthy controls were enrolled prospectively. Genotyping of HLA-DP was performed. The expression levels of HLA-DP molecules in peripheral blood B cells and monocytes were measured by flow cytometry. The transcription levels of HLA-DPB1 mRNA in peripheral blood mononuclear cells (PBMC) were measured by real time-PCR. The results were compared among different groups Results: There was no statistically significant difference of the distributions of HLA-DPB1*0501/HLA-DPB1*0501, HLA-DPB1*0501/X and X/X genotypes and the frequencies of allele of HLA-DPB1*0501 among NMOSD, MS patients and healthy controls (P=0.96 and 0.71, respectively). The expression levels of HLA-DP on the surface of B cells in NMOSD patients, especially in remission phase patients, were significantly higher than those in healthy controls(212±328 and 374±394 vs 55±57, P=0.049 and 0.002, respectively). The expression levels of HLA-DP on the surface of monocytes in NMOSD patients in acute phase were significantly higher than those in healthy controls(158±175 vs 65±90, P=0.025). The transcription levels of PMBC HLA-DPB1 mRNA in acute phase and remission phase of NMOSD patients were significantly higher than those in healthy controls (3.0±1.4 and 2.9±1.3 vs 1.5±1.4, P=0.000 and 0.003, respectively). The expression levels of HLA-DP molecules on the surface of peripheral blood B cells and monocytes and the transcription levels of PMBC HLA-DPB1 mRNA in MS patients at the acute and remission stages were not significantly different from those in healthy controls. The expression levels of HLA-DP molecules on the surface of B cells in patients with HLA-DPB1*0501/HLA-DPB1*0501, HLA-DPB1*0501/X and X/X genotypes were statistically different (P=0.017). Conclusion: HLA-DP gene transcription and molecular expression levels in antigen presenting cells may affect the susceptibility and disease status of NMOSD patients, while HLA-DPB1*0501 allele may affect the transcription and molecular expression levels of HLA-DP gene in antigen presenting cells.

Interleukin-6 plays a critical role in aldosterone-induced macrophage recruitment and infiltration in the myocardium

Macrophages play an important role in aldosterone-induced myocardial fibrosis, in which the first key steps are macrophage recruitment and infiltration. We hypothesized that IL-6 may be a key mediator of aldosterone-induced macrophage recruitment and infiltration. To test this hypothesis, we designed cell studies with a human monocytic cell line THP-1 that with monocyte/macrophage functions to explore the signaling pathway of aldosterone-induced macrophage infiltration, and further investigated the phenomenon and consequent pathway in aldosterone-infused mice studies. The results showed that aldosterone induced the expression of IL-6 via mineralocorticoid receptors, and enhanced THP-1 cell migration and infiltration. Further experiments using a protease array and siRNA revealed that expressions of MMP-1 and MMP-9 were associated with aldosterone-induced macrophage infiltration. In addition, aldosterone-induced MMP-1 and MMP-9 expressions were mediated via cyclooxygenase-II and prostaglandin E2/EP-2 and EP-4 receptors. In aldosterone-infused mice, mRNA expressions of MMP-1, MMP-9 and COX-2 in peripheral blood monocytic cells were significantly increased. Moreover, the number of mouse macrophage-restricted F4/80 protein-positive cells in the myocardium was significantly higher in the aldosterone-infused mice compared with control mice. The increase in F4/80-positive cells in the myocardium was suppressed in the aldosterone-infused mice with the aldosterone antagonist eplerenone or anti-IL-6 antibody treatment. In conclusion, interleukin-6 played an important role in aldosterone-induced macrophage recruitment and infiltration in the myocardium.

Left Ventricular Dysfunction in Patients With Primary Aldosteronism: A Propensity Score-Matching Follow-Up Study With Tissue Doppler Imaging

Background

Primary aldosteronism is the most common cause of secondary hypertension and is associated with left ventricular hypertrophy. However, whether aldosterone excess is responsible for left ventricular (LV) diastolic dysfunction is unknown.

Methods and Results

We prospectively enrolled 129 patients with aldosterone‐producing adenoma and 120 patients with essential hypertension, and analyzed their clinical, biochemical, and echocardiographic data, including tissue Doppler images. The patients with aldosterone‐producing adenoma were reevaluated 1 year after adrenalectomy. After propensity score matching, there were 105 patients in each group. The patients with aldosterone‐producing adenoma had worse diastolic function than the patients with essential hypertension, as reflected by lower e′ (P<0.001) and higher E/e′ (P=0.003). Multivariate analysis showed that LV diastolic function was significantly correlated with age (P<0.001), sex (P<0.001), body mass index (P=0.002), systolic blood pressure (P=0.004), creatinine (P=0.008), and log‐transformed aldosterone‐renin ratio (P=0.003). After adrenalectomy, the patients with aldosterone‐producing adenoma had significant improvements in LV diastolic function as reflected by an increase in e′ (P=0.003) and decrease in E/e′ (P=0.002). The change in E/e′ was independently correlated with baseline E/e′ (P<0.001) and change in LV mass index (P=0.006).

Conclusions

The patients with primary aldosteronism had worse LV diastolic function than the patients with essential hypertension after propensity score matching, and this could be reversed after adrenalectomy, suggesting that aldosterone excess may induce LV diastolic dysfunction.

U-shaped relationship between left ventricular mass index and estimated glomerular filtration rate in patients with primary aldosteronism

Estimated glomerular filtration rate (eGFR) is an important topic in patients with primary aldosteronism (PA). However, the relationship between left ventricular structure and eGFR is unclear. We conducted a prospective, observational, and cross-sectional study to analyze 168 patients with PA and 168 propensity score-matched patients with essential hypertension (EH) as the control group, matched by age, gender, and systolic blood pressure. In the patients with PA, the eGFR was not correlated with left ventricular mass index (LVMI; r=-0.065, p=0.404), while in the patients with EH, the eGFR was negatively correlated with LVMI (r=-0.309, p<0.001). To test whether eGFR had a non-linear relationship with LVMI among the patients with PA, we stratified the patients with PA according to the tertile of eGFR (low, medium, and high tertile). The medium tertile of patients had a significantly lower LVMI than those in the other two tertiles (LVMI: 143.5±41.6, 120.5±40.5, and 133.1±34.3 g/m², from the lowest to highest tertile of eGFR; analysis of covariance p=0.032). The medium tertile of eGFR is associated with lowest LVMI. Patients with PA with high and low eGFR were associated with higher LVMI. The findings implied that the reasons for an increased LVMI in patients with PA may be different to those in patients with EH.

IL-6 trans-signalling contributes to aldosterone-induced cardiac fibrosis

Aims

An excess of aldosterone results in cardiac remodelling and fibrosis. Interleukin-6 (IL-6) is a key mediator in the fibrotic process; however, the effect of aldosterone on the expression of IL-6 remains unclear. We investigated whether aldosterone induces the expression of IL-6 and thereby contributes to the fibrotic process.

Methods and results

In this clinical study, we prospectively enrolled 25 patients with primary aldosteronism (PA) and 26 patients with essential hypertension (EH). The PA patients had higher plasma IL-6 levels, left ventricular mass index, degree of myocardial fibrosis, and more impaired diastolic function than the EH patients. In addition, plasma IL-6 levels were positively correlated with 24-h urinary aldosterone and echocardiographic parameters. In cell studies, we investigated the possible molecular mechanism how aldosterone-induced IL-6 secretion and the further effects of collagen production. Aldosterone significantly induced IL-6 protein and mRNA production in human umbilical vein endothelial cells. Intracellular signalling occurred through the mineralocorticoid receptor/PI3K/Akt/NF-kB pathway. In cardiac fibroblasts, IL-6 trans-signalling played a critical role in aldosterone-induced IL-6-enhanced fibrosis-related factor expression. To further investigate the role of IL-6 trans-signalling in aldosterone-induced cardiac fibrosis, we measured the severity of myocardial fibrosis in aldosterone infusion mice models including an IL-6 chemical inhibitor and Sgp130 Knockin Transgenic Mice. Mice receiving recombinant soluble gp130 and Sgp130 Knockin Transgenic Mice prevented myocardial fibrosis and cardiac hypertrophy by aldosterone infusion.

Conclusions

IL-6 trans-signalling contributes to aldosterone-induced cardiac fibrosis.

The relationship among cardiac structure, dietary salt and aldosterone in patients with primary aldosteronism

Salt intake is highly associated with cardiac structure in patients with primary aldosteronism (PA). We investigated the association among dietary salt intake, aldosterone and left ventricular mass in patients with PA. We enrolled 158 patients with PA and 158 patients with essential hypertension. We measured 24-hour urinary sodium (UNa) and aldosterone (UAldo) level and echocardiography parameters. In patients with PA, the UAldo level was positively correlated with left ventricular mass index (LVMI; r=0.231, p=0.007). The UNa level was not linearly correlated with left ventricular structural parameters in patients with PA. To test if UNa has a non-linear relationship with LVMI among patients with PA, we categorized the participants according to the tertile of UNa (low, median, and high tertile). PA patients with medium tertile of UNa had significant lower LVMI than the other two groups (LVMI: 144.1 ± 42.9, 121.1 ± 33.4, and 136.7 ± 32.8 g/m2, from the lowest to the highest tertile of Una; analysis of variance p=0.006, post-hoc p <0.05). Multifactor analysis of variance confirmed this finding after adjustment for clinical parameters. Post-hoc analyses revealed that the high UNa tertile was associated with higher left ventricular end-diastolic volume compared with medium UNa tertile; while the low UNa tertile was associated with higher mean wall thickness compared with medium UNa tertile. The findings imply the reasons for increased LVMI may be different in patients with the highest and lowest UNa tertile. In conclusion, the medium tertile of 24-hour UNa is associated with lowest LVMI in patients with PA.

Effects of 12 weeks of atorvastatin therapy on myocardial fibrosis and circulating fibrosis biomarkers in statin-naïve patients with hypertension with atherosclerosis

The purpose of this study was to assess the effects of 12 weeks of atorvastatin treatment on myocardial fibrosis in patients with hypertension with atherosclerosis. 15 statin-naïve participants (11 males; mean age 67±10 years) with atherosclerosis were given atorvastatin (40 mg/day) for 12 weeks and underwent echocardiography including ultrasonic tissue characterization by cyclic variation of integrated backscatter (CVIBS). Serum galectin-3 and fibrosis markers including aminoterminal propeptide of type III procollagen (PIIINP), matrix metalloproteinase-2, metalloproteinase-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) were also analyzed. After 12 weeks of atorvastatin (40 mg/day) treatment, serum total cholesterol and low-density lipoprotein cholesterol decreased significantly (204±31 to 140±24 mg/dL and 133±26 to 69±17 ng/mL, respectively, both p<0.001). In myocardial fibrosis analysis, CVIBS increased significantly (6.6±1.9 to 8.5±2.7 dB, p=0.024). In addition, the circulating fibrosis markers serum PIIINP and TIMP-1 decreased significantly (9.5±2.7 to 6.4±1.4 ng/mL, p=0.012 and 299±65 to 250±45 ng/mL, p=0.024, respectively). 12 weeks of medium dose atorvastatin treatment resulted in a significant reduction in myocardial fibrosis as evaluated by morphofunctional parameters and plasma markers of tissue fibrosis.

Trial registration number

NTC00172419; results.

Aldosterone Induces Tissue Inhibitor of Metalloproteinases-1 Expression and Further Contributes to Collagen Accumulation

Aldosterone induces myocardial fibrosis. Tissue inhibitor of metalloproteinases-1 (TIMP-1) is a key factor of myocardial fibrosis. This study tested the hypothesis that aldosterone induces TIMP-1 expression and contributes to the fibrotic process. We prospectively enrolled 54 patients with primary aldosteronism, and measured plasma TIMP-1 and echocardiographic parameters. In the cell study, we investigated the possible molecular mechanism by which aldosterone induces TIMP-1 secretion and the effects on collagen accumulation. In the animal study, we measured serum TIMP-1 levels, cardiac TIMP-1 levels, and cardiac structure in an aldosterone infusion mouse model using implantation of aldosterone pellets. In patients with primary aldosteronism, plasma TIMP-1 was correlated with 24-hour urinary aldosterone, left ventricular mass, and impairment of left ventricular diastolic function. In human cardiac fibroblasts, TIMP-1 protein and mRNA expressions were significantly increased by aldosterone through the glucocorticoid receptor/PI3K/Akt/nuclear factor-κB pathway. TIMP-1 small-interfering RNA significantly reduced aldosterone-induced collagen accumulation, and aldosterone did not alter the levels of collagen1a1 or matrix metalloproteinase-1 mRNA. The aldosterone-induced TIMP-1 expression was inversely related to matrix metalloproteinase-1 activity. Furthermore, in the animal model, the serum and cardiac levels of TIMP-1 were significantly elevated in the mice that received aldosterone infusion. This elevation was blocked by RU-486 but not by eplerenone, suggesting that the effect was through glucocorticoid receptors. In a long-term aldosterone infusion model, serum TIMP-1 was associated with serum aldosterone level, cardiac structure, and fibrosis. In conclusion, aldosterone induced TIMP-1 expression in vivo and in vitro. This increased TIMP-1 expression resulted in enhanced collagen accumulation via the suppression of matrix metalloproteinase-1 activity.

The relation among aldosterone, galectin-3, and myocardial fibrosis: a prospective clinical pilot follow-up study

Primary aldosteronism has been associated with myocardial fibrosis, and is the most common cause of secondary hypertension. We previously showed that aldosterone can induce the secretion of galectin-3. The aim of this study was to investigate the association between myocardial fibrosis and plasma galectin-3 level in patients with primary aldosteronism. We prospectively analyzed 11 patients with aldosterone-producing adenoma (APA) who received adrenalectomy from December 2006 to October 2008, and 17 patients with essential hypertension as controls. Levels of plasma galectin-3 were determined in both groups, and both groups underwent echocardiography with cyclic variations of integrated backscatter (CVIBS) to characterize tissue initially and 1 year after surgery in the APA group. Diastolic blood pressure, concentration of plasma aldosterone and aldosterone-renin ratio were significantly higher, and serum potassium level and plasma renin activity significantly lower in the APA group compared to the controls. In addition, left ventricular mass index was significantly higher and CVIBS significantly lower in the APA group (7.3±2.0 vs 9.2±1.7 dB, p=0.015). Furthermore, the concentration of plasma galectin-3 was significantly higher in the APA group (2.1±0.9 vs 1.1±0.6 ng/mL, p=0.005) compared to the controls. CVIBS was correlated to plasma galectin-3 level. In the APA group, CVIBS increased significantly (7.3±2.0 to 9.2±2.4 dB, p=0.032) and plasma galectin-3 decreased (2.1±0.9 to 1.2±0.6, p=0.049) 1 year postadrenalectomy. The patients with APA had increased myocardial fibrosis, and this was associated with a higher plasma galectin-3 level. Both increased myocardial fibrosis and plasma galectin-3 level recovered at least partially after adrenalectomy.

TRIAL REGISTRATION NUMBER

200611031R; Results.

Aldosterone Impairs Vascular Smooth Muscle Function: From Clinical to Bench Research

CONTEXT

The effect of aldosterone on vascular smooth muscle cell function is still unclear. One method to measure vascular smooth muscle cell function is endothelial-independent vascular dilation, for which the key factor is sarcoplasmic reticulum calcium adenosine triphosphatase (SERCA).

OBJECTIVE

Our objective was to investigate the effect of aldosterone on vascular smooth muscle cell function and SERCA regulation.

DESIGN

We prospectively analyzed 35 patients with primary aldosteronism (PA; 32 patients with aldosterone-producing adenoma and three patients with idiopathic hyperaldosteronism) and 30 patients with essential hypertension (EH) who were enrolled as the control group. Flow and nitrate-mediated dilation were performed in both groups and 1 year after adrenalectomy in the patients with aldosterone-producing adenoma. In addition, we investigated the effect of aldosterone on SERCA regulation in human aortic smooth muscle cells.

SETTING

This study took place in an academic clinical research center.

PARTICIPANTS

Participants included 35 patients with PA and 30 patients with EH.

INTERVENTIONS

Adrenalectomy was undertaken in patients with aldosterone-producing adenoma.

RESULTS

The PA patients had significantly lower flow-mediated dilation (FMD) and nitrate-mediated dilation (NMD) values than the patients with EH (FMD: 13 ± 6 vs 16 ± 4; NMD: 16 ± 6 vs 19 ± 5; both P < .05). FMD/NMD were significantly correlated with log 24 hour-urine aldosterone (FMD: r = -0.287, P = .048; NMD: r = -0.402, P = .005) but not blood pressure. The impaired FMD and NMD values were significantly restored 1 year after adrenalectomy (FMD: 11 ± 4 to 19 ± 7; NMD: 15 ± 6 to 21 ± 6; both P < .01). Under confocal microscopy, aldosterone was shown to suppress the expression of SERCA2a of human aortic smooth muscle cells. Aldosterone significantly suppressed the expression of SERCA2a from 10(-8) M in mRNA and protein levels. This suppression was through down-regulation of mineralocorticoid receptor dependent mitochondrial transcription factors A and B2.

CONCLUSIONS

Aldosterone impairs vascular smooth muscle cell function and suppresses SERCA 2a expression.

The Association between Glomerular Hyperfiltration and Left Ventricular Structure and Function in Patients with Primary Aldosteronism

BACKGROUND

Glomerular hyperfiltration has been recently noticed as an important issue in primary aldosteronism (PA) patients. However, its effect on the cardiovascular system remains unknown.

METHODS

We prospectively analyzed 47 PA patients including 11 PA patients with estimated glomerular filtration rate (eGFR) > 130 ml/min per 1.73 m2 (group 1), and 36 PA patients with eGFR 90-110 ml/min per 1.73 m2 (group 2). Fourteen essential hypertension (EH) patients with eGFR 90-110 ml/min per 1.73 m2 were included as the control group (group 3). Echocardiography including left ventricular mass index (LVMI) measurement and tissue Doppler imaging (TDI) was performed. Predicted left ventricular mass (LVM) was calculated. Inappropriate LVM was defined as an excess of > 35% from the predicted value.

RESULTS

The value of LVMI decreased significantly in order from groups 1 to 3 (group 1>2>3). While group 2 had a significantly higher percentage of inappropriate LVM than group 3, the percentage of inappropriate LVM were comparable in groups 1 and 2. Group 1 had a higher mitral E velocity, E/A ratio than that of group 2. In the TDI study, the E/E' ratio also decreased significantly in order from groups 1 to 3 (group 1>2>3). Group 2 had lower E' than that of group 3, although the E' of group 1 and 2 were comparable.

CONCLUSIONS

Although PA patients with glomerular hyperfiltration were associated with higher LVMI, higher mitral E velocity, higher E/E' ratio, they had comparable E' with PA patients with normal GFR. This phenomenon may be explained by higher intravascular volume in this patient group.

Aldosterone induced galectin-3 secretion in vitro and in vivo: from cells to humans

Context

Patients with primary aldosteronism are associated with increased myocardial fibrosis. Galectin-3 is one of the most important mediators between macrophage activation and myocardial fibrosis.

Objective

To investigate whether aldosterone induces galectin-3 secretion in vitro and in vivo.

Methods and Results

We investigated the possible molecular mechanism of aldosterone-induced galectin-3 secretion in macrophage cell lines (THP-1 and RAW 264.7 cells). Aldosterone induced galectin-3 secretion through mineralocorticoid receptors via the PI3K/Akt and NF-κB transcription signaling pathways. In addition, aldosterone-induced galectin-3 expression enhanced fibrosis-related factor expression in fibroblasts. We observed that galectin-3 mRNA from peripheral blood mononuclear cells and serum galectin-3 levels were both significantly increased in mice implanted with aldosterone pellets on days 7 and 14. We then conducted a prospective preliminary clinical study to investigate the association between aldosterone and galectin-3. Patients with aldosterone-producing adenoma had a significantly higher plasma galectin-3 level than patients with essential hypertension. One year after adrenalectomy, the plasma galectin-3 level had decreased significantly in the patients with aldosterone-producing adenoma.

Conclusion

This study demonstrated that aldosterone could induce galectin-3 secretion in vitro and in vivo.

Association between urine aldosterone and diastolic function in patients with primary aldosteronism and essential hypertension

OBJECTIVE

To investigate the association between aldosterone and cardiac diastolic dysfunction.

DESIGN AND METHODS

We prospectively enrolled 20 patients with primary aldosteronism (PA) and 22 patients with essential hypertension (EH). Plasma aldosterone concentration, plasma renin activity, and 24-h urine aldosterone level were measured. Echocardiography, including tissue Doppler image recordings, was performed.

RESULTS

PA patients had a significantly higher left ventricular (LV) mass index and worse LV diastolic function than those in EH patients. Among various measures of aldosterone, log-transformed 24-h urine aldosterone level had the most consistent correlation with diastolic function.

CONCLUSIONS

Aldosterone is strongly associated with LV diastolic dysfunction. Twenty-four hour urine aldosterone is a good indicator to evaluate the impact of aldosterone on LV diastolic function.

Comparison the prognostic value of galectin-3 and serum markers of cardiac extracellular matrix turnover in patients with chronic systolic heart failure

BACKGROUND

Galectin-3 (Gal-3) shows the ability of survival prediction in heart failure (HF) patients. However, Gal-3 is strongly associated with serum markers of cardiac extracellular matrix (ECM) turnover. The aim of this study is to compare the impact of Gal-3 and serum markers of cardiac ECM turnover on prognostic prediction of chronic systolic HF patients.

METHODS

Serum Gal-3, brain natriuretic peptide (BNP), extracellular matrix including type I and III aminoterminal propeptide of procollagen (PINP and PIIINP), matrix metalloproteinase-2, 9 (MMP-2, 9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) were analyzed. Cox regression analysis was used for survival analysis.

RESULTS

A total of 105 (81 male) patients were enrolled. During 980±346 days follow-up, 17 patients died and 36 episodes of HF admission happened. Mortality of these patients was significantly associated with the log PIIINP (β= 15.380; P=0.042), log TIMP-1(β= 44.530; P=0.003), log MMP-2 (β= 554.336; P<0.001), log BNP (β= 28.273; P=0.034). Log Gal-3 (β= 7.484; P=0.066) is borderline associated with mortality. Mortality or first HF admission of these patients was significantly associated with the log TIMP-1(β= 16.496; P=0.006), log MMP-2 (β= 221.864; P<0.001), log BNP (β= 5.999; P=0.034). Log Gal-3 (β= 4.486; P=0.095) only showed borderline significance. In several models adjusting clinical parameters, log MMP-2 was significantly associated with clinical outcome. In contrast, log Gal-3 was not.

CONCLUSION

The prognostic strength of MMP-2 to clinical outcome prediction in HF patients is stronger than Gal-3.

WITHDRAWN: Association between the levels of carboxy-terminal propeptide of type I procollagen and aldosterone in patients with primary aldosteronism and essential hypertension

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Serotonin transporter gene promoter region polymorphisms and serotonin transporter expression in the colonic mucosa of irritable bowel syndrome patients

BACKGROUND

The role of serotonin transporter (SERT) gene polymorphism in irritable bowel syndrome (IBS) has been demonstrated. However, the expression of SERT mRNA and proteins in the colonic mucosa with different 5-HTT gene-linked polymorphic region (5-HTTLPR) genotypes remains unknown. We examined SERT mRNA and protein levels in colon biopsies from patients with different 5-HTTLPR genotypes and evaluated the links between the polymorphism and the expression levels.

METHODS

Two hundred and fifty-four patients with IBS and 120 healthy subjects were studied. DNA samples were extracted from peripheral blood and genotyped by polymerase chain reaction (PCR). SERT mRNA and protein levels were evaluated by quantitative real time PCR and western blotting. The promoter efficiency of the serotonin transporter promoter (SERT-P) was evaluated with luciferase reporter system.

KEY RESULTS

The frequency of the L/L genotype in C-IBS group was significantly higher than that in the control and D-IBS. However, the S/S genotype in D-IBS was significantly higher than that in C-IBS. The transcriptional efficiency of the L/L genotype was significantly higher than that in the L/S and S/S genotype. Patients with the L/L genotype demonstrated increased production of the SERT protein when compared with L/S and S/S patients. The l variant increased SERT promoter activity by 2.43-fold when compared with the s variant.

CONCLUSIONS & INFERENCES

Polymorphism in the promoter region of the SERT gene can influence the expression of SERT mRNA and the levels of the SERT protein in the colonic mucosa, thereby playing a key role in motility-related symptoms of IBS patients.

An Escherichia coli mutant deficient in pyruvate oxidase activity due to altered phospholipid activation of the enzyme

The pyruvate oxidase (pyruvate:ferricytochrome b(1) oxidoreductase, EC 1.2.2.2) of Escherichia coli is markedly activated by phospholipids in vitro. To test the physiological relevance of this activation, we isolated an E. coli mutant producing an oxidase that is deficient in activation by (and binding to) phospholipids. The mutant oxidase could be fully activated by a specific proteolytic cleavage, indicating that the catalytic site is normal. The mutant enzyme functions poorly in vivo, indicating that activation of the oxidase by phospholipids plays an important physiological role.

Inhibition of colicin e2 activity by bacterial lipopolysaccharide

Lipopolysaccharide isolated from colicin E2-sensitive Escherichia coli and from "receptor-minus" mutants inhibits the activity of colicin E2. Lipid A and the polysaccharide fraction obtained by mild acid hydrolysis of lipopolysaccharide are inactive either alone or when tested in combination. Periodate oxidation of lipopolysaccharide destroys over 85% of its inhibition activity.

Cognitive deficits in multiple system atrophy correlate with frontal atrophy and disease duration

BACKGROUND AND PURPOSE

Dementia remains an exclusion criterion in diagnosing multiple system atrophy (MSA). This study aimed to determine the cognitive changes and brain atrophy patterns in the Parkinsonian (MSA-P) and cerebellar (MSA-C) variants of MSA.

METHODS

Voxel-based morphometry (VBM) of magnetic resonance imaging (MRI) and neuro-psychological tests were applied to 10 MSA-C and 13 MSA-P patients, and compared to 37 age-matched controls. Correlation analyses were performed between cognitive test results and morphometric data extracted from the VBM data.

RESULTS

In neuro-psychological testing, the 23 MSA patients scored lower in the Stroop interference test and took longer in the trail-making test as compared with the controls, whereas MSA-C performed worse than MSA-P in the memory scores, Stroop test, and time to complete the trail-making test. MSA, as a group, showed atrophy in the cerebellum, insular cortex, fusiform gyrus, inferior orbito-frontal gyrus, superior temporal gyrus, and caudate nucleus. Memory scores correlated well with pre-frontal lobe atrophy but not in the insular area.

CONCLUSION

In conclusion, although dementia is not a typical presenting feature of MSA and is regarded as a sub-cortical movement disorder, frontal atrophy, cognitive changes, and dementia are identifiable as MSA progresses.

Serotonin transporter gene promoter polymorphism is associated with body mass index and obesity in non-elderly stroke patients

BACKGROUND

The serotonergic system is involved in the complex behavioral and physiological process in maintaining energy balance. Genetic factors regulating serotonergic function may have links with the development of obesity.

AIM

To investigate whether the 5-HTTLPR polymorphism of the serotonin transporter gene is associated with body mass index (BMI) and obesity in stroke patients.

SUBJECTS AND METHODS

The study included 376 patients (65.3+/-11.3 yr; male, 61.7%) with stroke. Associations between the 5-HTTLPR and BMI and obesity (BMI > or = 25 kg/m2) were examined in all subjects. In order to test age-dependent effects of the genetic variant, the association was also examined in the non-elderly subgroup (<65 yr) and the elderly subgroup (> or =65 yr) respectively.

RESULTS

For non-elderly subjects, the SS genotype was independently associated with increased BMI level (beta=1.84, p=0.037) and obesity (odds ratio 4.17, 95% CI 1.25-14.0, p=0.021) when the LL genotype was used as the reference. The association was not found for all patients or in the elderly subgroup. The LS genotype was not different from the LL genotype in BMI level or risk of obesity, either for all subjects or with regard to the non-elderly and elderly subgroups.

CONCLUSIONS

The SS genotype of 5-HTTLPR is an independent determinant of increased BMI level and obesity in non-elderly stroke patients but not in elderly patients. An age-dependent modification for the effect of the 5-HTTLPR on development of obesity is considered.

Life expectancy of patients with newly-diagnosed HIV infection in the era of highly active antiretroviral therapy

BACKGROUND

Limited data are available on the life expectancy of patients with newly-diagnosed HIV infection in the era of highly active antiretroviral therapy (HAART).

AIM

To provide such an estimate using a semi-parametric projection.

DESIGN

Statistical analysis.

METHODS

Follow-up data for patients newly diagnosed with HIV infection in Taiwan (HIV/AIDS Cohort) from 1 May 1997 to 30 April 2003 (n = 3351, only 1% are injecting drug users) were analysed using the Kaplan-Meier method. The survival function for an age- and gender-matched reference population was generated by the Monte Carlo method from the life-table of the general population. A constant excess hazard model was used to project long-term survival of HIV-infected patients, with linear extrapolation of a logit-transformed curve of survival ratio between HIV-infected patients and the reference population.

RESULTS

The 5-year survival rate was 58% in patients who had already developed AIDS at diagnosis (AIDS group), and 89% in those who had not (non-AIDS group). Extrapolation yielded an expected mean survival time of 10.6 years after diagnosis for the AIDS group, and 21.5 years after diagnosis for the non-AIDS group.

DISCUSSION

Our results support the expansion of HIV screening programs to minimize delay in diagnosis. With continuing advances in HAART, this estimate of survival in initially asymptomatic patients may be conservative. Their long life expectancy raises questions about what kind of preventive heath services should be offered. These should be addressed through further analysis of overall benefit and cost-effectiveness.

Arsenic removal by iron and manganese coated sand

In this study, as a promising technique for the treatment of both As(III) and As(V) at the same time in a single reactor, a column reactor containing both manganese-coated sand (MCS) and iron-coated sand (ICS), at different configuration of MCS and ICS, was used to treat wastewater contaminated with As(III). Prior to column experiments, batch experiments for the adsorption of As(V) by ICS were performed with variation of solution pH, ionic strength and types of background ions to investigate the effect of these parameters on the As(V) adsorption behaviour. As(V) adsorption onto ICS was quite similar with the variation of ionic strength by using NaNO3 as a background ion as well as in the presence of different types of background ions except phosphate. The adsorption curves shifted to the lower pH region with the increase of the initial arsenic concentration due to the finite number of adsorption sites on the ICS. For model prediction on the adsorption of As(V) onto ICS, the MINEQL program employing an inner-sphere complexation and a diffuse layer model was used. Model predictions generally agreed well with experimental results. From the column test, column system packed with equal ratio of MCS and ICS was identified as the best system due to a promising oxidation efficiency of As(III) to As(V) by MCS and adsorption of As(V) by both MCS and ICS.