Giuseppe Mercuro

Metabolic effect of telmisartan and losartan in hypertensive patients with metabolic syndrome

BackgroundMetabolic syndrome is a cluster of common cardiovascular risk factors that includes hypertension and insulin resistance. Hypertension and diabetes mellitus are frequent comorbidities and, like metabolic syndrome, increase the risk of cardiovascular events. Telmisartan, an antihypertensive agent with evidence of partial peroxisome proliferator-activated receptor activity-gamma (PPARγ) activity, may improve insulin sensitivity and lipid profile in patients with metabolic syndrome.MethodsIn a double-blind, parallel-group, randomized study, patients with World Health Organization criteria for metabolic syndrome received once-daily doses of telmisartan (80 mg, n = 20) or losartan (50 mg, n = 20) for 3 months. At baseline and end of treatment, fasting and postprandial plasma glucose, insulin sensitivity, glycosylated haemoglobin (HBA1c) and 24-hour mean systolic and diastolic blood pressures were determined.ResultsTelmisartan, but not losartan, significantly (p < 0.05) reduced free plasma glucose, free plasma insulin, homeostasis model assessment of insulin resistance and HbAic. Following treatment, plasma glucose and insulin were reduced during the oral glucose tolerance test by telmisartan, but not by losartan. Telmisartan also significantly reduced 24-hour mean systolic blood pressure (p < 0.05) and diastolic blood pressure (p < 0.05) compared with losartan.ConclusionAs well as providing superior 24-hour blood pressure control, telmisartan, unlike losartan, displayed insulin-sensitizing activity, which may be explained by its partial PPARγ activity.

Low testosterone levels are associated with coronary artery disease in male patients with angina

Historically, high androgen levels have been linked with an increased risk for coronary artery disease (CAD). However, more recent data suggest that low androgen levels are associated with adverse cardiovascular risk factors, including an atherogenic lipid profile, obesity and insulin resistance. The aim of the present study was to evaluate the relationship between plasma sex hormone levels and presence and degree of CAD in patients undergoing coronary angiography and in matched controls. We evaluated 129 consecutive male patients (mean age 58±4 years, range 43–72 years) referred for diagnostic coronary angiography because of symptoms suggestive of CAD, but without acute coronary syndromes or prior diagnosis of hypogonadism. Patients were matched with healthy volunteers. Out of 129 patients, 119 had proven CAD; in particular, 32 of them had one, 63 had two and 24 had three vessel disease, respectively. Patients had significantly lower levels of testosterone than controls (9.8±6.5 and 13.5±5.4 nmol/l, P<0.01) and higher levels of gonadotrophin (12.0±1.5 vs 6.6±1.9 IU/l and 7.9±2.1 vs 4.4±1.4, P<0.01 for follicle-stimulating hormone and luteinizing hormone, respectively). Also, both bioavailable testosterone and plasma oestradiol levels were lower in patients as compared to controls (0.84±0.45 vs 1.19±0.74 nmol/l, P<0.01 and 10.7±1.4 vs 13.3±3.5 pg/ml, P<0.05). Hormone levels were compared in cases with one, two or three vessel disease showing significant differences associated with increasing severity of coronary disease. An inverse relationship between the degree of CAD and plasma testosterone levels was found (r=−0.52, P<0.01). In conclusion, patients with CAD have lower testosterone and oestradiol levels than healthy controls. These changes are inversely correlated to the degree of CAD, suggesting that low plasma testosterone may be involved with the increased risk of CAD in men.

Trimetazidine improves left ventricular function in diabetic patients with coronary artery disease: a double-blind placebo-controlled study

BackgroundPatients with diabetic cardiomyopathy have an impaired myocardial glucose handling and distal distribution of coronary atherosclerosis. Trimetazidine, an anti-ischemic metabolic agent, improves myocardial glucose utilization though inhibition of fatty acid oxidation. Aim of the present study was to evaluate whether the metabolic effect of trimetazidine on left ventricular function in patients with diabetic cardiomyopathy.Methods32 patients (24 males and 8 females, mean (SE) age = 67 ± 6 years) with type 2 diabetes and ischemic cardiomyopathy were randomized to receive either trimetazidine (20 mg, t.d.s.) or placebo (t.d.s.) for six months in a randomized parallel study. Patients performed an echocardiogram at baseline and after 6 months.ResultsDemographic data were comparable between the two groups. After six month baseline left ventricular end-diastolic diameters increased from 62.4 ± 1.7 to 63 ± 2.1 mm in the placebo group, while decreased from 63.2 ± 2.1 to 58 ± 1.6 mm (p < 0.01 compared to baseline) in the trimetazidine group. Compared to baseline, left ventricular ejection fraction increased by 5.4 ± 0.5% (p < 0.05) in the trimetazidine group while remained unchanged in the placebo group -2.4 ± 1.1% (NS), p < 0.01 between groups. A significant improvement in wall motion score index and in the E/A wave ratio was detected in patients treated with trimetazidine, but not in those receiving placebo.Conclusionin diabetic patients with ischemic heart disease trimetazidine added to standard medical therapy has beneficial effect on left ventricular volumes and on left ventricular ejection fraction compared to placebo. This effect may be related to the effect of trimetazidine upon cardiac glucose utilization.

Metformin improves endothelial function in patients with metabolic syndrome.

Background.  Metabolic Syndrome (MS) is associated with impaired endothelial function and increased cardiovascular risk. Insulin resistance is a key feature of MS and plays an important role in the pathogenesis of endothelial dysfunction. Aim of the present study was to evaluate the effect of metformin on endothelial function and insulin resistance, assessed by the homeostasis model (HOMA‐IR, homeostasis model assessment‐insulin resistance), in patients with MS.

Evidence of a role of endogenous estrogen in the modulation of autonomic nervous system

We studied heart rate variability in 14 healthy women before and after oophorectomy compared with 14 matched women who underwent hysterectomy with ovarian conservation. Surgical menopause induced a decline in cardiac vagal modulation with a shift toward sympathetic hyperactivity. Recovery of the baseline condition after 3 months of estrogen replacement therapy in oophorectomized women suggests a role of estrogen in the autonomic nervous control of the cardiovascular system.

Protective effects of the angiotensin II receptor blocker telmisartan on epirubicin-induced inflammation, oxidative stress, and early ventricular impairment

BACKGROUND Oxidative stress and RAAS play an important role in the occurrence of anthracyclines-induced cardiotoxicity. Telmisartan, an angiotensin II type 1 receptor blocker, inhibits activation of superoxide sources and induces anti-inflammatory effects. METHODS The possible role of telmisartan in preventing myocardial damage induced by epirubicin (EPI) was investigated. Forty-nine patients free from cardiovascular diseases affected by a variety of solid cancers were examined. Eligible patients were randomized to receive telmisartan (40 mg/d; TEL, n = 25) or placebo (PLA, n = 24) starting 1 week before chemotherapy. Patients were studied by means of echocardiography, tissue Doppler, and strain and strain rate (SR) imaging. We also measured plasma levels of inflammatory and oxidative stress markers. All parameters were assessed at baseline and 7 days after every new EPI dose of 100 mg/m(2). RESULTS An impairment of the SR peak was observed at the EPI dose of 200 mg/m(2), with no significant differences between TEL and PLA (1.41 +/- 0.31 vs 1.59 +/- 0.36/s). At growing cumulative doses of EPI, SR normalized only in TEL, showing a significant difference in comparison to PLA at EPI doses of 300 mg/m(2) (1.69 +/- 0.42 vs 1.34 +/- 0.18/s, P < .001) and 400 mg/m(2) (1.74 +/- 0.27 vs 1.38 +/- 0.24/s, P < .001). Moreover, a significant increase in reactive oxygen species and interleukin-6 was found in PLA; but these remained unchanged in TEL. CONCLUSIONS We confirmed that EPI-induced cardiotoxicity is primarily related to the inactivation of the cardiac antioxidant defenses. In addition, we showed that telmisartan can reduce EPI-induced radical species, antagonize the inflammation, and reverse the early myocardial impairment.

Estradiol-17β reduces blood pressure and restores the normal amplitude of the circadian blood pressure rhythm in postmenopausal hypertension

After menopause, both systolic (SBP) and diastolic (DBP) blood pressure (BP) become higher in women than in men of the same age, suggesting that estrogen deficiency may influence the age-related increase in BP. We studied 30 postmenopausal women (mean age, 55 +/- 5.7 years; time from menopause, 2-5 years) affected by mild hypertension with no target-organ complications by means of 24-h BP monitoring. None of the group were undergoing estrogen replacement therapy or taking antihypertensive drugs. According to a randomized, double-blind protocol, subjects received patches of transdermal estradiol-17beta (E2) or a matched placebo, with crossover after a 7-day washout period. In 12 patients the 24-h peak-to-trough variation in SBP and DBP amounted to less than 10% (nondippers). Administration of E2 significantly decreased 24-h SBP and DBP in the whole cohort (P < .05). Furthermore, E2 restored the expected reduction in BP during nighttime in the nondipper subgroup. It is well known that estrogen replacement therapy protects against the development of both cardiovascular diseases and stroke. Our data suggest that this activity could be attributed, at least in part, to the activity of E2 in preserving physiologic circadian fluctuation of BP.

Gender determinants of cardiovascular risk factors and diseases.

This article addresses the various aspects concerning gender dissimilarities in the cardiovascular system. It examines sex differences in the genetic susceptibility to cardiovascular disease (CVD) development or outcome: with the presence of either XX or XY chromosomes, every cell is sexually differentiated and there exist postpuberal differences between male and female cardiovascular systems. The main action mechanisms of sex steroid hormones are discussed, mainly as to testosterone (Te) in men and 17beta-estradiol (E2) and progesterone (Pro) in women. In women, susceptibility to CVD is known to increase in the postmenopausal period, when the ovarian hormone function expires. Some concepts of the sex-based differences in anatomy and physiology are also explained. Although they have the same structural elements, women and men use them in a different way to guarantee cardiovascular system homeostasis. Some examples of differences between men and women in pathological cardiovascular function are given. A further important issue regards the prevalence and role of cardiovascular risk factors in the two genders. Compared to boys of the same age, adolescent girls and premenopausal women have a more favorable risk profile: lower blood pressure (BP), less atherogenic lipid profile, and lower prevalence of cardiovascular risk factors. Women develop CVD later than men and diabetic women have a considerably higher mortality rate compared to men of the same age. Finally, there exist several clinically significant differences between men and women as to prevalence, presentation, management and outcome of CVD. Clinical peculiarities related to gender in presentation of some CVDs, such as coronary heart disease (CHD), stroke and heart failure, are described. We are absolutely convinced that only an accurate knowledge of the sex-specific pathophysiology may allow determination of the appropriate diagnostic instruments and to implement tailored treatments of CVD in men and women.

Role of endothelial progenitor cells in restenosis and progression of coronary atherosclerosis after percutaneous coronary intervention: a prospective study.

OBJECTIVES We prospectively investigated the relationship of circulating endothelial progenitor cells at time of percutaneous coronary intervention to the subsequent development of in-stent restenosis or progression of coronary atherosclerosis. BACKGROUND Endothelial progenitor cells provide an endogenous repair mechanism of the dysfunctional endothelium and therefore can play a pathogenic role in coronary atherosclerosis. METHODS We studied 155 consecutive stable angina patients (92 men, age 60 +/- 11 years). All patients had flow cytometry the day before elective percutaneous coronary intervention in order to derive subpopulations of endothelial progenitor cells. A control group of 20 normal subjects was considered for comparison. RESULTS At 8-month control angiography, 30 patients showed in-stent restenosis (restenosis group), 22 patients showed progression of coronary atherosclerosis (progression group), whereas the remaining 103 patients had neither in-stent restenosis nor progression of coronary atherosclerosis (stable group). Comparison of the 3 groups did not show any difference in risk factors, cardiac morphology and function, extension of coronary artery disease, and treatment. Absolute numbers of CD34+/KDR+/CD45- cells (i.e., progenitors of endothelial lineage) measured in the restenosis group (1.41 +/- 0.64 cells/microl) were significantly higher than in the progression, stable, and control groups (1.03 +/- 0.53 cells/microl, 1.07 +/- 0.46 cells/microl, and 0.95 +/- 0.44 cells/microl, respectively, p < 0.05). Similarly, CD133+/KDR+/CD45- cells (i.e., progenitors of endothelial cells at an earlier stage) were significantly higher in the restenosis (0.63 +/- 0.23 cells/microl) compared with progression, stable, and control groups (0.33 +/- 0.19 cells/microl, 0.41 +/- 0.32 cells/microl, and 0.36 +/- 0.15 cells/microl, respectively, p < 0.001). Also, numbers of CD14+/CD45+ cells (i.e., which have a role in angiogenesis via a paracrine effect) were significantly different among the restenosis, progression, stable, and control groups (0.72 +/- 0.56 cells/microl vs. 0.51 +/- 0.52 cells/microl vs. 0.28 +/- 0.54 cells/microl vs. 0.62 +/- 0.67 cells/microl, respectively, p < 0.05), whereas CD105+/CD45-/CD34- cells (i.e., which have a receptor for transforming growth factor-beta) were similar among groups. CONCLUSIONS Patients with restenosis have higher numbers of subpopulations of endothelial progenitor cells that incorporate into endothelial cells or play a role in arteriogenesis compared with controls and patients with either progression of coronary atherosclerosis or stable disease.

Effects of Acute Administration of Transdermal Estrogen on Postmenopausal Women With Systemic Hypertension

We studied 16 postmenopausal women with mild to moderate hypertension according to a randomized, double-blind protocol. They received patches of transdermal estradiol-17beta rated to deliver 100 mg/day of substance or matched placebo. A 24-hour ambulatory blood pressure (BP) monitoring was performed at baseline and after drug administrations. Our data show that estradiol-17beta exerts beneficial effects, both in lowering elevated BP levels and in maintaining a uniform BP control over 24 hours. Estrogen replacement therapy could be considered when significant changes in BP occur during the postmenopausal period.