Abstract
Context
In postmenopausal women, adipose tissue (AT) levels of estrogens exceed circulating concentrations. Although increased visceral AT after menopause is related to metabolic diseases, ...little is known about differences in estrogen metabolism between different AT depots.
Objective
We compared concentrations of and metabolic pathways producing estrone and estradiol in abdominal subcutaneous and visceral AT in postmenopausal women.
Design, Setting, Patients, and Interventions
AT and serum samples were obtained from 37 postmenopausal women undergoing surgery for nonmalignant gynecological reasons. Serum and AT estrone, estradiol, and serum estrone sulfate (E1S) concentrations were quantitated using liquid chromatography-tandem mass spectrometry. Activity of steroid sulfatase and reductive 17β-hydroxysteroid dehydrogenase enzymes was measured using radiolabeled precursors. Messenger RNA (mRNA) expression of estrogen-converting enzymes was analyzed by real-time reverse transcription quantitative polymerase chain reaction.
Results
Estrone concentration was higher in visceral than subcutaneous AT (median, 928 vs 706 pmol/kg; P = 0.002) and correlated positively with body mass index (r = 0.46; P = 0.011). Both AT depots hydrolyzed E1S to estrone, and visceral AT estrone and estradiol concentrations correlated positively with serum E1S. Compared with visceral AT, subcutaneous AT produced more estradiol from estrone (median rate of estradiol production, 1.02 vs 0.57 nmol/kg AT/h; P = 0.004). In visceral AT, the conversion of estrone to estradiol increased with waist circumference (r = 0.65; P = 0.022), and estradiol concentration correlated positively with mRNA expression of HSD17B7 (r = 0.76; P = 0.005).
Conclusions
Both estrone and estradiol production in visceral AT increased with adiposity, but estradiol was produced more effectively in subcutaneous fat. Both AT depots produced estrone from E1S. Increasing visceral adiposity could increase overall estrogen exposure in postmenopausal women.
We compared estrogen concentrations and synthesis in subcutaneous and visceral adipose tissue in postmenopausal women and found visceral adiposity to be related to greater overall estrogen exposure.
CONTEXT A recent meta-analysis demonstrated that statin therapy is associated with excess risk of developing diabetes mellitus. OBJECTIVE To investigate whether intensive-dose statin therapy is ...associated with increased risk of new-onset diabetes compared with moderate-dose statin therapy. DATA SOURCES We identified relevant trials in a literature search of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (January 1, 1996, through March 31, 2011). Unpublished data were obtained from investigators. STUDY SELECTION We included randomized controlled end-point trials that compared intensive-dose statin therapy with moderate-dose statin therapy and included more than 1000 participants who were followed up for more than 1 year. DATA EXTRACTION Tabular data provided for each trial described baseline characteristics and numbers of participants developing diabetes and experiencing major cardiovascular events (cardiovascular death, nonfatal myocardial infarction or stroke, coronary revascularization). We calculated trial-specific odds ratios (ORs) for new-onset diabetes and major cardiovascular events and combined these using random-effects model meta-analysis. Between-study heterogeneity was assessed using the I2 statistic. RESULTS In 5 statin trials with 32 752 participants without diabetes at baseline, 2749 developed diabetes (1449 assigned intensive-dose therapy, 1300 assigned moderate-dose therapy, representing 2.0 additional cases in the intensive-dose group per 1000 patient-years) and 6684 experienced cardiovascular events (3134 and 3550, respectively, representing 6.5 fewer cases in the intensive-dose group per 1000 patient-years) over a weighted mean (SD) follow-up of 4.9 (1.9) years. Odds ratios were 1.12 (95% confidence interval CI, 1.04-1.22; I2 = 0%) for new-onset diabetes and 0.84 (95% CI, 0.75-0.94; I2 = 74%) for cardiovascular events for participants receiving intensive therapy compared with moderate-dose therapy. As compared with moderate-dose statin therapy, the number needed to harm per year for intensive-dose statin therapy was 498 for new-onset diabetes while the number needed to treat per year for intensive-dose statin therapy was 155 for cardiovascular events. CONCLUSION In a pooled analysis of data from 5 statin trials, intensive-dose statin therapy was associated with an increased risk of new-onset diabetes compared with moderate-dose statin therapy.
•Estrone is the dominant adipose tissue estrogen in premenopausal women.•Estrone levels in adipose tissue are much higher than in the circulation.•Adipose tissue converts estrone sulfate to estrone, ...and estrone to estradiol.•Waist circumference correlates with higher estradiol production in subcutaneous fat.
Although the ovaries produce the majority of estrogens in women before menopause, estrogen is also synthesized in peripheral tissues such as adipose tissue (AT). The typical female AT distribution, concentrated in subcutaneous and femoro-gluteal regions, is estrogen-mediated, but the significance of estrogen synthesis in AT of premenopausal women is poorly understood.
Serum and subcutaneous and visceral AT homogenates from 28 premenopausal women undergoing non-malignant surgery were analyzed for estrone, estradiol, and serum estrone sulfate (E1S) concentrations with liquid chromatography-tandem mass spectrometry. Isotopic precursors were used to measure enzyme activities of estrone-producing steroid sulfatase and estradiol-producing 17β-hydroxysteroid dehydrogenases (17β-HSD). Messenger RNA (mRNA) expression levels of genes for estrogen-metabolizing enzymes were analyzed using real-time reverse transcription quantitative polymerase chain reaction.
While estradiol was the predominant circulating active estrogen, estrone dominated in AT, with a higher concentration in visceral than subcutaneous AT (median, 2657 vs 1459 pmol/kg; P = 0.002). Both AT depots converted circulating E1S to estrone, and estrone to estradiol. Median levels of estrone were five to ten times higher in subcutaneous and visceral AT than in serum (P < 0.001) and the estradiol level in visceral AT was 1.3 times higher than in serum (P < 0.005). The local estrone concentration in visceral AT correlated positively with mRNA expression of estrone-producing enzyme aromatase (r = 0.65, P = 0.003). Waist circumference correlated positively with increased estradiol production in subcutaneous AT (r = 0.60, P = 0.039).
Premenopausal AT demonstrated high estrogenic enzyme activity and considerable local estrogen concentrations. This may be a factor promoting female-typical AT distribution in premenopausal women.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract Background Statins may reduce cardiovascular (CV) morbidity in patients with mild-to-moderate elevations in liver enzyme levels. This post-hoc analysis of the IDEAL study compared intensive ...versus moderate statin therapy for the prevention of CV events in coronary heart disease patients with normal and elevated baseline levels of serum alanine aminotransferase (ALT). Methods Cox regression analysis was used to investigate the effect of atorvastatin 80 mg/day versus simvastatin 20–40 mg/day on the risk of IDEAL study end points in patients with normal baseline ALT (defined as ALT < ULN upper limit of normal) versus elevated baseline ALT (ALT ≥ ULN). Results Of 8863 IDEAL patients with non-missing baseline ALT values, 7782 (87.8%) had an ALT < ULN and 1081 (12.2%) had an ALT ≥ ULN. In patients with elevated baseline ALT, major CV event rates were 11.5% for simvastatin and 6.5% for atorvastatin, indicating a significant risk reduction with intensive statin therapy (hazard ratio, 0.556; 95% confidence interval, 0.367–0.842; p = 0.0056). Significant heterogeneity of treatment effect was observed for major CV events, cerebrovascular events, and major coronary events, with a trend towards treatment difference for the other outcomes, indicating a greater benefit with atorvastatin in the elevated ALT group. Conclusions The CV benefit of intensive lipid lowering with atorvastatin compared with a more moderate regimen with simvastatin was generally greater in patients with mildly-to-moderately elevated baseline ALT than patients with normal baseline ALT. Moderate elevations in liver enzyme levels should not present a barrier to prescribing statins, even at higher doses, in high-risk patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
CONTEXT Evidence suggests that more intensive lowering of low-density lipoprotein cholesterol (LDL-C) than is commonly applied clinically will provide further benefit in stable coronary artery ...disease. OBJECTIVE To compare the effects of 2 strategies of lipid lowering on the risk of cardiovascular disease among patients with a previous myocardial infarction (MI). DESIGN, SETTING, AND PARTICIPANTS The IDEAL study, a prospective, randomized, open-label, blinded end-point evaluation trial conducted at 190 ambulatory cardiology care and specialist practices in northern Europe between March 1999 and March 2005 with a median follow-up of 4.8 years, which enrolled 8888 patients aged 80 years or younger with a history of acute MI. INTERVENTIONS Patients were randomly assigned to receive a high dose of atorvastatin (80 mg/d; n = 4439), or usual-dose simvastatin (20 mg/d; n = 4449). MAIN OUTCOME MEASURE Occurrence of a major coronary event, defined as coronary death, confirmed nonfatal acute MI, or cardiac arrest with resuscitation. RESULTS During treatment, mean LDL-C levels were 104 (SE, 0.3) mg/dL in the simvastatin group and 81 (SE, 0.3) mg/dL in the atorvastatin group. A major coronary event occurred in 463 simvastatin patients (10.4%) and in 411 atorvastatin patients (9.3%) (hazard ratio HR, 0.89; 95% CI, 0.78-1.01; P = .07). Nonfatal acute MI occurred in 321 (7.2%) and 267 (6.0%) in the 2 groups (HR, 0.83; 95% CI, 0.71-0.98; P = .02), but no differences were seen in the 2 other components of the primary end point. Major cardiovascular events occurred in 608 and 533 in the 2 groups, respectively (HR, 0.87; 95% CI, 0.77-0.98; P = .02). Occurrence of any coronary event was reported in 1059 simvastatin and 898 atorvastatin patients (HR, 0.84; 95% CI, 0.76-0.91; P<.001). Noncardiovascular death occurred in 156 (3.5%) and 143 (3.2%) in the 2 groups (HR, 0.92; 95% CI, 0.73-1.15; P = .47). Death from any cause occurred in 374 (8.4%) in the simvastatin group and 366 (8.2%) in the atorvastatin group (HR, 0.98; 95% CI, 0.85-1.13; P = .81). Patients in the atorvastatin group had higher rates of drug discontinuation due to nonserious adverse events; transaminase elevation resulted in 43 (1.0%) vs 5 (0.1%) withdrawals (P<.001). Serious myopathy and rhabdomyolysis were rare in both groups. CONCLUSIONS In this study of patients with previous MI, intensive lowering of LDL-C did not result in a significant reduction in the primary outcome of major coronary events, but did reduce the risk of other composite secondary end points and nonfatal acute MI. There were no differences in cardiovascular or all-cause mortality. Patients with MI may benefit from intensive lowering of LDL-C without an increase in noncardiovascular mortality or other serious adverse reactions. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT00159835.
To study whether high-dose versus usual-dose statin treatment reduces the incidence of peripheral artery disease (PAD) and what is the effect of high-dose statin treatment on cardiovascular disease ...(CVD) outcome in patients with PAD.
In the Incremental Decrease in End Points Through Aggressive Lipid Lowering trial, 8888 post-myocardial infarction patients were randomised to high-dose or usual-dose statin therapy (atorvastatin 80 mg/day vs simvastatin 20-40 mg/day). We investigated the effect of high-dose versus usual-dose statins on the pre-specified outcome PAD incidence, and additionally performed a posthoc analysis of the efficacy of high-dose statins in reducing CVD risk among patients with PAD. During a median follow-up of 4.8 years, 94 patients (2.2%) receiving atorvastatin and 135 patients (3.2%) receiving simvastatin developed PAD (HR=0.70, 95% CI 0.53 to 0.91; p=0.007). The risk of major coronary events was almost twofold higher in patients with PAD at baseline, but was no longer significant after adjusting for the adverse cardiovascular risk profile. In PAD patients, major coronary events occurred in fewer patients in the atorvastatin group (14.4%) than in the simvastatin group (20.1%), but the difference did not reach statistical significance. (HR=0.68, 95% CI 0.41 to 1.11; p=0.13). Atorvastatin treatment significantly reduced overall cardiovascular (p=0.046) and coronary events (p=0.004), and coronary revascularisation (p=0.007) in these patients.
High-dose statin therapy with atorvastatin significantly reduced the incidence of PAD compared with usual-dose statin therapy with simvastatin. Patients with a history of PAD at baseline were at higher risk of future coronary events and this risk was reduced by high-dose atorvastatin treatment.
NCT00159835 (URL: http://clinicaltrials.gov/show/NCT00159835).
The effect of statins on risk of heart failure (HF) hospitalization and HF death remains uncertain. We aimed to establish whether statins reduce major HF events.
We searched Medline, EMBASE, and the ...Cochrane Central Register of Controlled Trials for randomized controlled endpoint statin trials from 1994 to 2014. Collaborating trialists provided unpublished data from adverse event reports. We included primary- and secondary-prevention statin trials with >1000 participants followed for >1 year. Outcomes consisted of first non-fatal HF hospitalization, HF death and a composite of first non-fatal HF hospitalization or HF death. HF events occurring <30 days after within-trial myocardial infarction (MI) were excluded. We calculated risk ratios (RR) with fixed-effects meta-analyses. In up to 17 trials with 132 538 participants conducted over 4.3 weighted standard deviation (SD) 1.4 years, statin therapy reduced LDL-cholesterol by 0.97 mmol/L (weighted SD 0.38 mmol/L). Statins reduced the numbers of patients experiencing non-fatal HF hospitalization (1344/66 238 vs. 1498/66 330; RR 0.90, 95% confidence interval, CI 0.84-0.97) and the composite HF outcome (1234/57 734 vs. 1344/57 836; RR 0.92, 95% CI 0.85-0.99) but not HF death (213/57 734 vs. 220/57 836; RR 0.97, 95% CI 0.80-1.17). The effect of statins on first non-fatal HF hospitalization was similar whether this was preceded by MI (RR 0.87, 95% CI 0.68-1.11) or not (RR 0.91, 95% CI 0.84-0.98).
In primary- and secondary-prevention trials, statins modestly reduced the risks of non-fatal HF hospitalization and a composite of non-fatal HF hospitalization and HF death with no demonstrable difference in risk reduction between those who suffered an MI or not.
This study was designed to assess the relationship of high-density-lipoprotein cholesterol (HDL-C), HDL particle size, and apolipoprotein A-I (apoA-I) with the occurrence of coronary artery disease ...(CAD), with a focus on the effect of very high values of these parameters.
High plasma levels of HDL-C and apoA-I are inversely related to the risk of CAD. However, recent data suggest that this relationship does not hold true for very high HDL-C levels, particularly when a preponderance of large HDL particles is observed.
We conducted a post-hoc analysis of 2 prospective studies: the IDEAL (Incremental Decrease in End Points through Aggressive Lipid Lowering; n = 8,888) trial comparing the efficacy of high-dose to usual-dose statin treatment for the secondary prevention of cardiovascular events, and the EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk case-control study, including apparently healthy individuals who did (cases, n = 858) or did not (control patients, n = 1,491) develop CAD during follow-up. In IDEAL, only HDL-C and apoA-I were available; in EPIC-Norfolk, nuclear magnetic resonance spectroscopy-determined HDL particle sizes were also available.
In the IDEAL study, higher HDL-C proved a significant major cardiac event risk factor following adjustment for age, gender, smoking, apoA-I, and apoB. A similar association was observed for HDL particle size in EPIC-Norfolk. Increased risk estimates were particularly present in the high ends of the distributions. In contrast, apoA-I remained negatively associated across the major part of its distribution in both studies.
When apoA-I and apoB are kept constant, HDL-C and HDL particle size may confer risk at very high values. This does not hold true for very high levels of apoA-I at fixed levels of HDL-C and apoB. These findings may have important consequences for assessment and treatment of CAD risk.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We determined the ability of in-trial measurements of triglycerides (TGs) to predict new cardiovascular events (CVEs) using data from the Incremental Decrease in End Points through Aggressive Lipid ...Lowering (IDEAL) and Treating to New Targets (TNT) trials. The trials compared atorvastatin 80 mg/day with moderate-dose statin therapy (simvastatin 20 to 40 mg/day in IDEAL and atorvastatin 10 mg/day in TNT) in patients with clinically evident coronary heart disease or a history of myocardial infarction. The outcome measurement in the present research was CVE occurring after the first year of the trial. After adjusting for age, gender, and study, risk of CVEs increased with increasing TGs (p <0.001 for trend across quintiles of TGs). Patients in the highest quintile had a 63% higher rate of CVEs than patients in the lowest quintile (hazard ratio 1.63, 95% confidence interval 1.46 to 1.81) and the relation of TGs to risk was apparent even within the normal range of TGs. The ability of TG measurements to predict risk decreased when high-density lipoprotein cholesterol and apolipoprotein B:apolipoprotein A-1 were included in the statistical analysis, and it was abolished with inclusion of further variables (diabetes, body mass index, glucose, hypertension, and smoking; (p = 0.044 and 0.621, respectively, for trend across quintiles of TGs). Similar results were obtained in patients in whom low-density lipoprotein cholesterol had been lowered to guideline-recommended levels. In conclusion, even slightly increased TG levels are associated with higher risk of recurrence of CVEs in statin-treated patients and should be considered a useful marker of risk.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Context:
It has been shown that breast tumor actively produces and metabolizes steroid hormones. However, little is known about the possible mechanisms through which the nonmalignant adipose tissue ...contributes to steroid hormone metabolism.
Objective:
We compared the metabolic pathways producing active estradiol in breast sc adipose tissue of postmenopausal women with or without breast cancer.
Design and Setting:
Serum and adipose tissue samples were obtained during elective surgery.
Patients:
We studied postmenopausal women undergoing mastectomy due to an estrogen receptor-positive breast tumor (n = 14) and women undergoing breast reduction mammoplasty (n = 14).
Interventions:
Estrone, estradiol, and estradiol fatty acyl ester concentrations were determined by liquid chromatography-tandem mass spectrometry. mRNA expression levels of estrogen-converting enzymes were analyzed by quantitative RT-PCR.
Results:
Estradiol concentration in breast sc adipose tissue was lower in women with cancer than in controls (median 33 vs 62 pmol/kg; P = .002), whereas the serum concentrations did not differ. Also, the mRNA expression for 17β-hydroxysteroid dehydrogenase type 12 was lower in the adipose tissue of women with cancer compared with controls (0.19 ± 0.10 vs 0.37 ± 0.21, P = .018).
Conclusions:
Estrogen metabolism is differentially regulated in the adipose tissue of women with or without cancer. In the sc adipose tissue proximal to breast tumor 17β-hydroxysteroid dehydrogenase type 12 expression is lower than in controls, which could indicate that the conversion of estrone to estradiol is decreased. Further studies are needed to establish the clinical significance of our findings in the development and growth of breast cancer in postmenopausal women.
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