Mechanisms of hypertension in the cardiometabolic syndrome. J Hypertens. 2009;27:441-451. [PMID: 19262221 DOI: 10.1097/hjh.0b013e32831e13e5]

Novel Techniques, Biomarkers and Molecular Targets to Address Cardiometabolic Diseases

Cardiometabolic diseases (CMDs) are interrelated and multifactorial conditions, including arterial hypertension, type 2 diabetes, heart failure, coronary artery disease, and stroke. Due to the burden of cardiovascular morbidity and mortality associated with CMDs' increasing prevalence, there is a critical need for novel diagnostic and therapeutic strategies in their management. In clinical practice, innovative methods such as epicardial adipose tissue evaluation, ventricular-arterial coupling, and exercise tolerance studies could help to elucidate the multifaceted mechanisms associated with CMDs. Similarly, epigenetic changes involving noncoding RNAs, chromatin modulation, and cellular senescence could represent both novel biomarkers and targets for CMDs. Despite the promising data available, significant challenges remain in translating basic research findings into clinical practice, highlighting the need for further investigation into the complex pathophysiology underlying CMDs.

Sodium - a systematic review for Nordic Nutrition Recommendations 2023

Blood pressure (BP) rises along with increasing sodium intake from early childhood to late adulthood, and leads to hypertension among most men and women living in Nordic and Baltic countries. Elevated BP is the leading global risk factor for premature deaths and disability-adjusted life-years. A reduction in sodium intake is essential in the prevention of hypertension in individuals, in the lowering of BP levels, in the treatment of hypertensive individuals, and in decreasing risks associated with elevated BP. There is a progressive linear dose-response relationship between sodium intake and BP beginning from a sodium intake of less than 0.8 g/day. Sodium reduction decreases BP linearly by a dose-response manner down to a sodium intake level of less than 2 g/day. Randomised intervention studies with a duration of at least 4 weeks confirm the efficiency and safety of reducing blood sodium intake to a level of less than 2 g/day. Results from prospective cohort studies show that higher sodium intake is positively associated with an increased risk of stroke and cardiovascular events and mortality among the general adult population, and the associations are linear in studies using proper sodium assessment methods. Analyses assessing sodium intake using at least two 24-h urine samples have shown a linear positive relationship between sodium intake and the risk of a cardiovascular event or death. Based on an overall evaluation of the available data, a limitation of the sodium intake to 2.0 g/day is suggested for adults. The optimal sodium intake level would be probably about 1.5 g/day. Sodium intake recommended for children can be extrapolated from the recommended sodium intake for adults. According to national dietary surveys, the average sodium intakes in Nordic countries range in adult men from 3.6 to 4.4 g/day and in adult women from 2.6. to 3.2 g/day, and in Baltic countries in men from 2.6 to 5.1 g/day and in women from 1.8 to 3.6 g/day.

Risk of Hypertension and Use of Antihypertensive Drugs in the Physically Active Population under-70 Years Old—Spanish Health Survey

Introduction: Reducing the prevalence of hypertension is a major priority of the World Health Organization (WHO). Its high prevalence and associated risks generate high economic and social costs. Physical activity (PA) is associated with a decrease in hypertension and in the use of antihypertensive drugs. Objective: To explore the association between PA levels (PAL), prevalence of hypertension and the use of antihypertensive drugs in Spanish population. To calculate risks of hypertension and use of antihypertensive in the inactive versus physically active population. Method: This cross-sectional study used data from 17717 individuals, sampled in the 2017 National Health Survey. Interaction by sex, age groups, body mass index (BMI), hypertension prevalence, antihypertensive drugs use and PAL, using a pairwise z-test, and dependence relationships between variables, were studied using a chi square test. Odds ratios of hypertension and antihypertensive drug use were calculated among the inactive and the physically active populations. Results: The findings showed a significant inverse association between prevalence of hypertension, antihypertensive use, and PAL in both sexes and different age and BMI groups, with lower prevalence of hypertension and antihypertensive use when PAL were higher. The risks of hypertension and antihypertensive use seems to be reduced when related to higher PAL compared to inactive people. Conclusions: High PAL is associated with lower prevalence of hypertension and lower antihypertensive use. Thus, being physically active or very active may reduce the risks of suffering from hypertension and the need to use antihypertensives compared to inactive people or walkers.

Cucurbitacins extracted from Cucumis melo L. (CuEC) exert a hypotensive effect via regulating vascular tone

As an effective medicine for jaundice in traditional Chinese medicine, Cucumis melo L. has been widely used in China. However, its effect on vascular function is still unclear. In this study, we extracted the compounds of Cucumis melo L., and the major ingredients were identified as cucurbitacins (CuEC, cucurbitacins extracted from Cucumis melo L.), especially cucurbitacin B. We replicated the toxicity in mice by intraperitoneal injection of a high dose of CuEC (2 mg/kg) and demonstrated that the cause of death was CuEC-induced impairment of the endothelial barrier and, thus, increased vascular permeability via decreasing VE-cadherin conjunction. The administration of low doses of CuEC (1 mg/kg) led to a decline in systolic blood pressure (SBP) without causing toxicity in mice. More importantly, CuEC dramatically suppressed angiotensin II (Ang II)-induced SBP increase. Further studies demonstrated that CuEC facilitated acetylcholine-mediated vasodilation in mesenteric arteries of mice. In vitro studies showed that CuEC induced vasodilation in a dose-dependent manner in mesenteric arteries of both mice and rats. Pretreatment with CuEC inhibited phenylephrine-mediated vasoconstriction. In summary, a moderate dose of CuEC reduced SBP by improving blood vessel tension. Therefore, our study provides new experimental evidence for developing new antihypertensive drugs.

Treatment Pattern and Factors Associated with Blood Pressure and Fasting Plasma Glucose Control among Patients with Type 2 Diabetes Mellitus in Police Referral Hospital in Ethiopia

BACKGROUND

The prevalence of T2DM in Ethiopia is on the rise according to certain studies. Appropriate management approaches are required to achieve desired goals of therapy in the clinical setup. This study was conducted to assess the treatment pattern and the factors associated with BP and FPG control among patients with T2DM in Federal Police Referral Hospital.

METHOD

An institution based cross sectional study was conducted from 15th October 2016 to 15th January 2017. A Systematic random sampling technique was employed in selecting the study participants. Data was collected using semi-structured interview and visiting medication records. SPSS version 20 was used for data analysis.

RESULTS

Out of a total of 414 participants who fulfilled the inclusion criteria, 361 were successfully interviewed and considered for further analysis. Target BP level was achieved in 206(57.1%) of the patients, whereas the proportion of hypertensive diabetics who attained the recommended BP target was 19.4% (n=40). Of the 361 participants who were checked about their current FPG level, only 142(39.3%) were found to be <130mg/dl. However, 87(24.1%) participants were found to control both BP and FPG levels. Gender, military status, comorbidity, type of therapy and dietary adherence showed a statistically significant association with outcome variables.

CONCLUSION

The proportion of participants with T2DM who achieved target BP, FPG or both was suboptimal. A comprehensive approach that involves targeted education on self-management strategies, individualized treatment plans, and continuous evaluation of treatment outcomes should be practiced.

Management of Cardiovascular Risk Factors in Type 2 Diabetes Mellitus Patients

People with Type 2 diabetes mellitus (T2DM), compared with non-diabetic individuals, have increased cardiovascular risk. Part of this excess risk is associated with a higher prevalence of other cardiovascular risk factors in these patients, such as obesity, dyslipidaemia, and hypertension. However, the increased cardiovascular risk present in T2DM cannot be attributed entirely to the high prevalence of traditional risk factors and other non-traditional risk factors may also be important for people with T2DM. Evidence suggests that in patients with T2DM, treatment of cardiovascular risk factors is very important in reducing the risk of cardiovascular disease (CVD). The poor control of risk factors observed in the diabetic population supports the need for more aggressive treatment of modifiable cardiovascular risk factors, especially in patients with previous CVD. There is little evidence on the independent association between traditional and non-traditional cardiovascular risk factors, however these risk factors do not appear in isolation and are produced at the same time, exacerbating the risk of a cardiovascular event. Targeting multiple markers of CVD risk offers the best chance of improving CVD outcomes. The objective of this review is to highlight the importance of managing cardiovascular risk factors in patients with T2DM.

Treatment of hypertensive patients with diabetes: beyond blood pressure control and focus on manidipine

Renin-angiotensin system inhibitors should be considered as the first-line therapy in the treatment of patients with hypertension and diabetes. However, most of the diabetic subjects with hypertension require at least two drugs to achieve blood pressure targets. The ACCOMPLISH trial suggested that the best combination in the treatment of high-risk hypertensive patients should include a renin-angiotensin system inhibitor and a dihydropyridine. However, not all dihydropyridines block the same receptors. Those dihydropyridines that block T-type calcium channel blockers may provide additional advantages. A number of studies suggest that compared with amlodipine, manidipine have the same antihypertensive efficacy, but with a lesser risk of ankle edema. In addition, manidipine, but not amlodipine, significantly reduces urinary albumin excretion rates.

Minimizing tacrolimus decreases the risk of new-onset diabetes mellitus after liver transplantation

AIM: To investigate the impact of minimum tacrolimus (TAC) on new-onset diabetes mellitus (NODM) after liver transplantation (LT).

METHODS: We retrospectively analyzed the data of 973 liver transplant recipients between March 1999 and September 2014 in West China Hospital Liver Transplantation Center. Following the exclusion of ineligible recipients, 528 recipients with a TAC-dominant regimen were included in our study. We calculated and determined the mean trough concentration of TAC (cTAC) in the year of diabetes diagnosis in NODM recipients or in the last year of the follow-up in non-NODM recipients. A cutoff of mean cTAC value for predicting NODM 6 mo after LT was identified using a receptor operating characteristic curve. TAC-related complications after LT was evaluated by χ² test, and the overall and allograft survival was evaluated using the Kaplan-Meier method. Risk factors for NODM after LT were examined by univariate and multivariate Cox regression.

RESULTS: Of the 528 transplant recipients, 131 (24.8%) developed NODM after 6 mo after LT, and the cumulative incidence of NODM progressively increased. The mean cTAC of NODM group recipients was significantly higher than that of recipients in the non-NODM group (7.66 ± 3.41 ng/mL vs 4.47 ± 2.22 ng/mL, P < 0.05). Furthermore, NODM group recipients had lower 1-, 5-, 10-year overall survival rates (86.7%, 71.3%, and 61.1% vs 94.7%, 86.1%, and 83.7%, P < 0.05) and allograft survival rates (92.8%, 84.6%, and 75.7% vs 96.1%, 91%, and 86.1%, P < 0.05) than the others. The best cutoff of mean cTAC for predicting NODM was 5.89 ng/mL after 6 mo after LT. Multivariate analysis showed that old age at the time of LT (> 50 years), hypertension pre-LT, and high mean cTAC (≥ 5.89 ng/mL) after 6 mo after LT were independent risk factors for developing NODM. Concurrently, recipients with a low cTAC (< 5.89 ng/mL) were less likely to become obese (21.3% vs 30.2%, P < 0.05) or to develop dyslipidemia (27.5% vs 44.8%, P <0.05), chronic kidney dysfunction (14.6% vs 22.7%, P < 0.05), and moderate to severe infection (24.7% vs 33.1%, P < 0.05) after LT than recipients in the high mean cTAC group. However, the two groups showed no significant difference in the incidence of acute and chronic rejection, hypertension, cardiovascular events and new-onset malignancy.

CONCLUSION: A minimal TAC regimen can decrease the risk of long-term NODM after LT. Maintaining a cTAC value below 5.89 ng/mL after LT is safe and beneficial.

The lysyl oxidase inhibitor (β-aminopropionitrile) reduces leptin profibrotic effects and ameliorates cardiovascular remodeling in diet-induced obesity in rats

Lysyl oxidase (LOX) is an extracellular matrix (ECM)-modifying enzyme that has been involved in cardiovascular remodeling. We explore the impact of LOX inhibition in ECM alterations induced by obesity in the cardiovascular system. LOX is overexpressed in the heart and aorta from rats fed a high-fat diet (HFD). β-Aminopropionitrile (BAPN), an inhibitor of LOX activity, significantly attenuated the increase in body weight and cardiac hypertrophy observed in HFD rats. No significant differences were found in cardiac function or blood pressure among any group. However, HFD rats showed cardiac and vascular fibrosis and enhanced levels of superoxide anion (O2(-)), collagen I and transforming growth factor β (TGF-β) in heart and aorta and connective tissue growth factor (CTGF) in aorta, effects that were attenuated by LOX inhibition. Interestingly, BAPN also prevented the increase in circulating leptin levels detected in HFD fed animals. Leptin increased protein levels of collagen I, TGF-β and CTGF, Akt phosphorylation and O2(-) production in both cardiac myofibroblasts and vascular smooth muscle cells in culture, while LOX inhibition ameliorated these alterations. LOX knockdown also attenuated leptin-induced collagen I production in cardiovascular cells. Our findings indicate that LOX inhibition attenuates the fibrosis and the oxidative stress induced by a HFD on the cardiovascular system. The reduction of leptin levels by BAPN in vivo and the ability of this compound to inhibit leptin-induced profibrotic mediators and ROS production in cardiac and vascular cells suggest that interactions between leptin and LOX regulate downstream events responsible for myocardial and vascular fibrosis in obesity.

Type 2 diabetes and cardiovascular disease: Have all risk factors the same strength?

Diabetes mellitus is a chronic condition that occurs when the body cannot produce enough or effectively use of insulin. Compared with individuals without diabetes, patients with type 2 diabetes mellitus have a considerably higher risk of cardiovascular morbidity and mortality, and are disproportionately affected by cardiovascular disease. Most of this excess risk is it associated with an augmented prevalence of well-known risk factors such as hypertension, dyslipidaemia and obesity in these patients. However the improved cardiovascular disease in type 2 diabetes mellitus patients can not be attributed solely to the higher prevalence of traditional risk factors. Therefore other non-traditional risk factors may be important in people with type 2 diabetes mellitus. Cardiovascular disease is increased in type 2 diabetes mellitus subjects due to a complex combination of various traditional and non-traditional risk factors that have an important role to play in the beginning and the evolution of atherosclerosis over its long natural history from endothelial function to clinical events. Many of these risk factors could be common history for both diabetes mellitus and cardiovascular disease, reinforcing the postulate that both disorders come independently from “common soil”. The objective of this review is to highlight the weight of traditional and non-traditional risk factors for cardiovascular disease in the setting of type 2 diabetes mellitus and discuss their position in the pathogenesis of the excess cardiovascular disease mortality and morbidity in these patients.

The potential role of leptin in the vascular remodeling associated with obesity

BACKGROUND/OBJECTIVES

Extracellular matrix (ECM) participates in the vascular remodeling associated with obesity. We investigated the effects of leptin on the production of ECM components in primary cultured vascular smooth muscle cells (VSMCs) and whether leptin could be a mediator of obesity-induced vascular remodeling.

METHODS

T he effects of leptin (100 ng ml(-1)) on ECM components and superoxide anion production (O(2)(.-)) were evaluated in presence or absence of the antioxidant melatonin (10(-)(3) mmol l(-1)) or the inhibitor of phosphatidylinositol 3'-kinase (PI3K), LY294002 (2 × 10(-)(4) mmol l(-1)) in VSMCs from adult rats in order to explore the role of both oxidative stress and the participation of PI3K/Akt pathway in the effects of leptin. ECM components and O(2)(.-) were quantified in the aortic media of male Wistar rats fed a high-fat diet (HFD; 33.5% fat), or a standard diet (CT; 3.5% fat) for 6 weeks.

RESULTS

In VSMCs, leptin enhanced gene and protein levels of collagen I, fibronectin, transforming growth factor (TGF)-β and connective tissue growth factor (CTGF) but did not change those of collagen III and galectin-3. Leptin also increased O(2)(.-) and Akt phosphorylation in VSMCs. These effects were prevented by the presence of either melatonin or LY294002, except O(2)(.-) production in the case of PI3K inhibition. The increase in body weight in HFD rats was accompanied by aorta thickening due to an increase in media area. The aortic fibrosis observed in HFD rats was associated with high levels of leptin, collagen type I, fibronectin, TGF-β, CTGF, phosphorylated Akt and O(2)(.-). Aortic leptin levels were positively correlated with total collagen, collagen I, TGF-β and CTGF levels. No differences were observed in the levels of collagen III, elastin or galectin-3 between both the groups.

CONCLUSIONS

Leptin could participate in the vascular remodeling and stiffness associated with obesity by ECM production in VSMCs through the activation of oxidative stress-PI3K/Akt pathway and the production of the profibrotic factors TGF-β and CTGF.

Revisiting the relationship between blood pressure and insulin-like growth factor-1

Conflicting evidence exists on the relationship between blood pressure (BP) and insulin-like growth factor-1 (IGF-1). We reviewed available articles and pooled extrapolated regression coefficients for the association between BP and total IGF-1 as reported in the literature and included additional data from 912 individuals from the general population. We identified 20 studies including 11 704 subjects. We also measured total IGF-1, insulin-like binding protein-3, and BP in 912 black and white men and women from South Africa (aged 20-70 years). When plotting positive and negative weighed regression coefficients (29 data points) against IGF-1, we found a significant positive relationship (r=0.31; P<0.001; n=11 704) intercepting the 0 point at 191 ng/mL IGF-1, suggesting an inverse BP/IGF-1 relationship in low IGF-1 conditions, and a positive relationship in overtly high IGF-1 conditions. In conclusion, our findings suggest that the relationship between BP and IGF-1 is dependent on, or related to, IGF-1 concentrations, as an expression of direct or reverse causality. Low IGF-1 bioavailability (associated with aging and vascular deterioration), resistance to IGF-1, and the complex interplay between IGF-1 and other vasoactive hormones could mask the vasoprotective functions of IGF-1 in cross-sectional studies or could modify their functions in prospective studies.

Pathophysiology of the diabetic kidney

Diabetes mellitus contributes greatly to morbidity, mortality, and overall health care costs. In major part, these outcomes derive from the high incidence of progressive kidney dysfunction in patients with diabetes making diabetic nephropathy a leading cause of end-stage renal disease. A better understanding of the molecular mechanism involved and of the early dysfunctions observed in the diabetic kidney may permit the development of new strategies to prevent diabetic nephropathy. Here we review the pathophysiological changes that occur in the kidney in response to hyperglycemia, including the cellular responses to high glucose and the responses in vascular, glomerular, podocyte, and tubular function. The molecular basis, characteristics, and consequences of the unique growth phenotypes observed in the diabetic kidney, including glomerular structures and tubular segments, are outlined. We delineate mechanisms of early diabetic glomerular hyperfiltration including primary vascular events as well as the primary role of tubular growth, hyperreabsorption, and tubuloglomerular communication as part of a "tubulocentric" concept of early diabetic kidney function. The latter also explains the "salt paradox" of the early diabetic kidney, that is, a unique and inverse relationship between glomerular filtration rate and dietary salt intake. The mechanisms and consequences of the intrarenal activation of the renin-angiotensin system and of diabetes-induced tubular glycogen accumulation are discussed. Moreover, we aim to link the changes that occur early in the diabetic kidney including the growth phenotype, oxidative stress, hypoxia, and formation of advanced glycation end products to mechanisms involved in progressive kidney disease.

A role for soluble ST2 in vascular remodeling associated with obesity in rats

BACKGROUND

The function of the Interleukin-33 (IL-33)/ST2 system has been mainly investigated on immunological aspects, but recent data suggest that this pathway plays also an important role in cardiovascular system and adipose tissue. Whereas IL-33 has been demonstrated to exert anti-inflammatory and protective effects, circulating soluble ST2 (sST2) has emerged as a prognostic biomarker in patients with myocardial infarction and heart failure. Furthermore, sST2 is increased in severe obesity, although its role in the pathogenesis of vascular remodeling associated with obesity is still not well defined.

METHODOLOGY/PRINCIPAL FINDINGS

Male Wistar rats fed standard diet (Control) or high fat diet (HFD) for 6 weeks. Aortic tunica media from diet-induced obese animals showed hypertrophy and fibrosis. The IL-33/ST2 system was spontaneously expressed in the aorta from Wistar rats. Administration of HFD in animals did not modify IL-33 expression at the transcriptional level. By contrast, HFD group showed an increase in aortic soluble sST2 and a decrease in the transmembrane isoform (ST2L) levels, resulting in decreased protective pathway activity. Aortic sST2 mRNA levels were associated with parameters showing vascular hypertrophy and fibrosis. In vitro experiments showed that primary cultured vascular smooth muscle cells (VSMCs) spontaneously expressed the IL-33/ST2 system. VSMCs stimulated with sST2 showed an increase in collagen type I, fibronectin and profibrotic factors.

CONCLUSIONS

This is the first study demonstrating a deleterious role for sST2 in the vascular remodeling associated with obesity. In addition, we demonstrated that sST2 may act not only as a decoy receptor by binding IL-33 and preventing ST2L, but also modulating ECM remodeling and turnover. Thus, sST2 could be a new therapeutic target to reduce vascular remodeling in the context of obesity.

Blood pressure relation to body composition and age: analysis of a nurse-led investigation and consultation program

BACKGROUND

Blood pressure (BP) increases with age and obesity. We have assessed the relative contribution of age and fatness to BP regulation in a healthy population investigated by nurse practitioners.

MATERIAL AND METHODS

Preventive investigation and counseling was offered at the entrance hall of the regional authority´s office in the town of Nitra by 2 nursing specialists who investigated 120 men and 276 women. In men the mean body mass index (BMI) was 26.8 kg/m2, mean weight was 84.4 kg, mean fat percentage was 23.3, mean age was 46.1 years, mean systolic BP was 133.1 mmHg, and mean diastolic BP was 82.5 mmHg. In women the mean BMI was 24.8 kg/m2, mean weight was 67.3 kg, mean fat percentage was 29.4, mean age was 45.4 years, mean systolic BP was 127.7 mmHg, and mean diastolic BP was 78.5 mmHg. Correlation analysis was performed and in multiple regression analysis we used BP values as the dependent variable and fat percentage and age as independent variables. Normality of variables distribution was checked and found satisfactorily.

RESULTS

Most of the subjects had an untreated component of metabolic syndrome. There was a correlation between BP values, age, and percent body fat. BP was regulated only to a certain degree by fatness and age, with the influence being relatively small. Our results showed that BP was more influenced by fatness than age, and body fatness was more related to higher systolic than to diastolic BP.

CONCLUSIONS

Age and fatness could explain BP values by only 3-30%, although BP was more influenced by fatness than by age. Nurse practitioners can effectively detect and motivate people with metabolic syndrome.

[Metabolic syndrome components in arterial hypertension]

The objectives of this study were to identify and compare the prevalence of metabolic syndrome among hypertensive individuals and people with normal blood pressure measurements. The metabolic syndrome definition used in this study is that of the National Cholesterol Education Program/Adult Treatment Panel (NCEP-ATP III). The data referring to the clinical and biochemical profiles were processed using the SPSS software to obtain absolute frequencies and percentages. The Student's t-test was used to compare the means, with values of p<0.05 considered statistically significant. The sample was comprised of 93 participants with normal blood pressure levels and 168 participants with hypertension. It was found that 60.7% of the individuals with hypertension had metabolic syndrome, versus 18.3% of those with normal blood pressure levels. Individuals with hypertension showed a significant difference in blood pressure levels (p<0.001), abdominal circumference (p<0.001), blood glucose (p<0.05) and plasma triglycerides (p<0.05). The frequency of cardiometabolic risks associated with metabolic syndrome is greater when hypertension is present.

Role of the Renin-Angiotensin system and aldosterone on cardiometabolic syndrome

Aldosterone facilitates cardiovascular damage by increasing blood pressure and through different mechanisms that are independent of its effects on blood pressure. In this respect, recent evidence involves aldosterone in the pathogenesis of metabolic syndrome. Although this relationship is complex, there is some evidence suggesting that different factors may play an important role, such as insulin resistance, renin-angiotensin-aldosterone system, oxidative stress, sodium retention, increased sympathetic activity, levels of free fatty acids, or inflammatory cytokines and adipokines. In addition to the classical pathway by which aldosterone acts through the mineralocorticoid receptors leading to sodium retention, aldosterone also has other mechanisms that influence cardiovascular tissue remodelling. Finally, overweight and obesity promote the adrenal secretion of aldosterone, increasing the predisposition to type 2 diabetes mellitus. Further studies are needed to better establish therapeutic strategies that act on the blockade of mineralocorticoid receptor in the treatment and prevention of cardiovascular diseases related to the excess of aldosterone and the metabolic syndrome.

IGF-1 and atherothrombosis: relevance to pathophysiology and therapy

IGF-1 (insulin-like growth factor-1) plays a unique role in the cell protection of multiple systems, where its fine-tuned signal transduction helps to preserve tissues from hypoxia, ischaemia and oxidative stress, thus mediating functional homoeostatic adjustments. In contrast, its deprivation results in apoptosis and dysfunction. Many prospective epidemiological surveys have associated low IGF-1 levels with late mortality, MI (myocardial infarction), HF (heart failure) and diabetes. Interventional studies suggest that IGF-1 has anti-atherogenic actions, owing to its multifaceted impact on cardiovascular risk factors and diseases. The metabolic ability of IGF-1 in coupling vasodilation with improved function plays a key role in these actions. The endothelial-protective, anti-platelet and anti-thrombotic activities of IGF-1 exert critical effects in preventing both vascular damage and mechanisms that lead to unstable coronary plaques and syndromes. The pro-survival and anti-inflammatory short-term properties of IGF-1 appear to reduce infarct size and improve LV (left ventricular) remodelling after MI. An immune-modulatory ability, which is able to suppress 'friendly fire' and autoreactivity, is a proposed important additional mechanism explaining the anti-thrombotic and anti-remodelling activities of IGF-1. The concern of cancer risk raised by long-term therapy with IGF-1, however, deserves further study. In the present review, we discuss the large body of published evidence and review data on rhIGF-1 (recombinant human IGF-1) administration in cardiovascular disease and diabetes, with a focus on dosage and safety issues. Perhaps the time has come for the regenerative properties of IGF-1 to be assessed as a new pharmacological tool in cardiovascular medicine.

Matsuda-DeFronzo insulin sensitivity index is a better predictor than HOMA-IR of hypertension in Japanese: the Tanno-Sobetsu study

Here we examined whether the Matsuda-DeFronzo insulin sensitivity index (ISI-M) is more efficient than the homeostasis model assessment of insulin resistance (HOMA-IR) for assessing risk of hypertension. Cross-sectional and longitudinal analyses were conducted using normotensive subjects who were selected among 1399 subjects in the Tanno-Sobetsu cohort. In the cross-sectional analysis (n=740), blood pressure (BP) level was correlated with HOMA-IR and with ISI-M, but correlation coefficients indicate a tighter correlation with ISI-M. Multiple linear regression analysis adjusted by age, sex, body mass index (BMI) and serum triglyceride level (TG) showed contribution of ISI-M and fasting plasma glucose, but not of HOMA-IR. In the longitudinal analysis (n=607), 241 subjects (39.7%) developed hypertension during a 10-year follow-up period, and multiple logistic regression indicated that age, TG, systolic BP and ISI-M, but not HOMA-IR, were associated with development of hypertension. In subjects <60 years old, odds ratio of new-onset hypertension was higher in the low ISI-M group (ISI-M, less than the median) than in the high ISI-M group for any tertile of BMI. In conclusion, ISI-M is a better predictor of hypertension than is HOMA-IR. Non-hepatic IR may be a determinant, which is independent of TG, BP level and BMI, of the development of hypertension.

Chronic sodium-retaining action of insulin in diabetic dogs

Insulin-mediated sodium retention is implicated as a mechanism for hypertension in metabolic syndrome and type II diabetes. However, there is no direct experimental evidence for a sustained antinatriuretic effect of insulin outside of rodents, and all previous studies in dogs have been negative. This study used a novel approach to test for a chronic sodium-retaining action of insulin in dogs, by testing the hypothesis that natriuresis in type I diabetes is dependent on the decrease in insulin, rather than being due solely to osmotic actions of hyperglycemia. Dogs were chronically instrumented and housed in metabolic cages. Fasting blood glucose in alloxan-treated dogs was maintained at ~65 mg/dl by continuous intravenous insulin infusion. Then, a 6-day diabetic period was induced by either 1) decreasing the insulin infusion to induce type I diabetes (D; blood glucose = 449 ± 40 mg/dl) or 2) clamping the insulin infusion and infusing glucose continuously (DG; blood glucose = 470 ± 56 mg/dl). Control urinary sodium excretion (UnaV) averaged 70 ± 5 (D) and 69 ± 5 (DG) meq/day and increased on day 1 in both groups. UnaV remained elevated in the D group (115 ± 15 meq/day days 2-6), but it returned to control in the DG group (69 ± 11 meq/day days 2-6) and was accompanied by decreased lithium clearance. Thus, insulin had a sustained antinatriuretic action that was triggered by increased glucose, and it was powerful enough to completely block the natriuresis caused by hyperglycemia. These data may reveal an unrecognized physiologic function of insulin as a protector against hyperglycemia-induced salt wasting in diabetes.

Plasma Proteomic Signature in Overweight Girls Closely Correlates with Homeostasis Model Assessment (HOMA), an Objective Measure of Insulin Resistance

Obesity is known to be associated with a large number of long-term morbidities, and while in some cases the relationship of obesity and the consequences is clear (for example, excess weight and lower extremity orthopedic problems) in others the mechanism is not as clear. One common system of categorizing overweight in terms of the likelihood of negative consequences involves using the concept of “metabolic syndrome”. We hypothesized that the development of a plasma protein profile of overweight adolescents with and without the metabolic syndrome might give a more precise and informative picture of the disease process than the current clinical categorization and permit early targeted intervention. For this paper, we used antibody microarrays to analyze the plasma proteome of a group of 15 overweight female adolescent patients. Upon analysis of the proteome, the overweight patients diverged from the nonoverweight female controls. Furthermore, the overweight patients were divided by the analysis into two population clusters, each with distinctive protein expression patterns. Interestingly, the clusters were characterized by differences in insulin resistance, as measured by HOMA. Categorization according to the presence or absence of the metabolic syndrome did not yield such clusters.

Blood pressure lowering in patients with diabetes--one level might not fit all

Hypertension and diabetes mellitus frequently occur together, leading to increased complications and mortality in patients with both these conditions. Blood pressure (BP) goals for patients with diabetes have consistently been more aggressive than for patients without diabetes. Although the benefits of lowering BP are well documented, data to support this more aggressive goal are lacking. In fact, lowering BP might not always be better. We review the available evidence regarding BP treatment in patients with hypertension and diabetes from randomized clinical trials, as well as available observational data. We also consider evidence related to the J-shaped curve, which reflects the relationship between BP and outcomes in patients with diabetes, and make recommendations for treatment of BP on the basis of a patient's individual risk, as opposed to on the basis of aggressive BP targets recommended by global guidelines. In the future, a personalized approach will maximize the benefits from treatment.

New-onset diabetes and cardiovascular events in essential hypertensives: a 6-year follow-up study

BACKGROUND

Controversy still exists regarding the impact of new-onset diabetes (NOD) on CV outcomes among patients with hypertension. Our aim was to determine the incidence of NOD in essential hypertensives and to evaluate its association with major cardiovascular (CV) events.

METHODS

We followed-up for a mean period of 6 years 1572 essential hypertensives (mean age 54.3 years, 696 males) for the incidence of NOD, as well as of fatal and non-fatal coronary artery disease and stroke. Based on the development of NOD, the cohort was divided into patients with pre-existing diabetes (10%), patients with NOD (10%) and those who remained free from diabetes.

RESULTS

During the follow-up period, new or recurrent cases of coronary artery disease and stroke events occurred at a rate of 5.6% (n = 88) and 4.65% (n = 73). The independent predictors for NOD were age (OR = 1.026, p = 0.041), waist circumference (OR = 1.044, p < 0.001), family history of diabetes (OR = 2.173, p = 0.003) and systolic BP at follow-up (OR 1.022, p = 0.044). The presence of NOD was independently associated with greater incidence of stroke (HR 2.404, p = 0.046), along with age (HR 1.078, p < 0.001), duration of hypertension (HR 1.039, p = 0.017) and office systolic blood pressure at follow-up (HR 1.022, p = 0.026), whereas development of NOD had no relationship with the incidence of coronary artery disease.

CONCLUSIONS

Our findings indicate the high incidence of NOD and its close association with stroke in essential hypertension. Poorer control of hypertension appears to be a common denominator of both NOD and stroke in this setting.

Epidemiological and economic burden of metabolic syndrome and its consequences in patients with hypertension in Germany, Spain and Italy; a prevalence-based model

BACKGROUND

The presence of metabolic syndrome in patients with hypertension significantly increases the risk of cardiovascular disease, type 2 diabetes and mortality. Our aim is to estimate the epidemiological and economic burden to the health service of metabolic syndrome in patients with hypertension in three European countries in 2008 and 2020.

METHODS

An age, sex and risk group structured prevalence based cost of illness model was developed using the United States Adult Treatment Panel III of the National Cholesterol Education Program criteria to define metabolic syndrome. Data sources included published information and public use databases on disease prevalence, incidence of cardiovascular events, prevalence of type 2 diabetes, treatment patterns and cost of management in Germany, Spain and Italy.

RESULTS

The prevalence of hypertension with metabolic syndrome in the general population of Germany, Spain and Italy was 36%, 11% and 10% respectively. In subjects with hypertension 61%, 22% and 21% also had metabolic syndrome. Incident cardiovascular events and attributable mortality were around two fold higher in subjects with metabolic syndrome and prevalence of type 2 diabetes was around six-fold higher. The economic burden to the health service of metabolic syndrome in patients with hypertension was been estimated at €24,427, €1,900 and €4,877 million in Germany, Spain and Italy and forecast to rise by 59%, 179% and 157% respectively by 2020. The largest components of costs included the management of prevalent type 2 diabetes and incident cardiovascular events. Mean annual costs per hypertensive patient were around three-fold higher in subjects with metabolic syndrome compared to those without and rose incrementally with the additional number of metabolic syndrome components present.

CONCLUSION

The presence of metabolic syndrome in patients with hypertension significantly inflates economic burden and costs are likely to increase in the future due to an aging population and an increase in the prevalence of components of metabolic syndrome.

Reinforcement of the adrenergic overdrive in the metabolic syndrome complicated by obstructive sleep apnea

BACKGROUND

Metabolic syndrome is characterized by a marked sympathetic overactivity. It is unknown, however, whether the neuroadrenergic activation can be ascribed to obstructive sleep apnoea (OSA), OSA exerts potentiating effects on the metabolic syndrome-related sympathetic activation and reflex/metabolic variables (insulin resistance) participate at the phenomenon.

METHODS AND RESULTS

We conducted a cross-sectional study of healthy individuals and metabolic syndrome patients recruited in our outpatient clinic. Fifty-five middle-age men classified according to Adult Treatment Panel III criteria and apnea-hypopnea index (overnight polysomnographic evaluation) as healthy controls without OSA and metabolic syndrome patients without and with OSA were studied. Blood pressure (Finapres), heart rate (ECG) and muscle sympathetic nerve activity (MSNA; microneurography) were measured at rest and during baroreflex manipulation. Compared with controls, patients with metabolic syndrome with and without OSA displayed higher waist-hip ratio, blood pressure, triglycerides and homeostasis model assessment index values but lower high-density lipoprotein cholesterol. MSNA was significantly higher in patients with metabolic syndrome without OSA than in controls (61.9 +/- 3.9 vs. 37.7 +/- 4.1 bursts/100 heartbeats, respectively, P < 0.01), a further marked increase being detected in patients with metabolic syndrome with OSA (77.1 +/- 4.3 bursts/100 heart beats, P < 0.01). Compared with controls, baroreflex control of heart rate and MSNA was markedly impaired in patients with metabolic syndrome with OSA, a further impairment in baroreflex-heart rate modulation being detected in metabolic syndrome with OSA. In the metabolic syndrome group as a whole, at the multivariate analysis, MSNA was significantly related to the apnoea-hypopnoea index but not to other variables.

CONCLUSION

Thus the sympathetic activation of metabolic syndrome occurs independently on OSA. OSA, however, markedly potentiates this neuroadrenergic abnormality via a hypoxic-dependent chemoreflex activation.

Associations of metabolic factors, especially serum retinol-binding protein 4 (RBP4), with blood pressure in Japanese--the Tanno and Sobetsu study

Excess secretion of various adipocyte-derived molecules has been linked with insulin resistance, obesity, diabetes, inflammation, atherosclerosis, and cardiovascular disease. Retinol-binding protein 4 (RBP4), one of the new adipocytokine, is recently reported to provide a link between insulin resistance and features of metabolic factors. Hypertension is one of the most influential risk factors among cardiovascular disease. We examined the relationship between systolic blood pressure (BP) levels and metabolic factors including homeostasis model assessment of insulin resistance (HOMA-R), high sensitivity c-reactive protein (hs-CRP), adiponectin, and RBP4. The subjects were 153 men aged 59 ± 14 years and 224 women aged 57 ± 14 years who had undergone medical check-ups in rural communities in 2007. Systolic BP was positively correlated with HOMA-R, hs-CRP and RBP4 but not with adiponectin in women. There was a positive significant relationship between serum RBP4 levels and blood pressure in women, but such a relationship was not found in men. Serum RBP4 levels were not correlated with HOMA-R in either men or women. Serum RBP4 levels negatively were correlated with estimated glomerular filtration rate (eGFR) in women but not in men. Multiple regression analysis revealed that serum RBP4 levels significantly were related to systolic BP independently of age, sex, body mass index (BMI), total cholesterol levels and eGFR. Our study showed that increased levels of RBP4 as well as HOMA-R and hs-CRP in women were significantly associated with increased levels of systolic BP.