Metabolically unhealthy individuals, either with obesity or not, have a higher risk of critical coronavirus disease 2019 outcomes than metabolically healthy individuals without obesity

BACKGROUND

This study aimed to determine the relative and independent contributions of impaired metabolic health and obesity to critical coronavirus disease 2019 (COVID-19).

METHODS

We analyzed 4069 COVID-19 patients between January and June 2020 in South Korea, classified into four groups according to metabolic health status and body mass index (BMI): metabolically healthy normal weight (MHNW), metabolically unhealthy normal weight (MUNW), metabolically healthy obesity (MHO), and metabolically unhealthy obesity (MUO). The primary outcome was a composite of intensive care unit (ICU) admission, invasive mechanical ventilation (IMV), extracorporeal membrane oxygenation (ECMO), and death. Multivariable Cox proportional hazard regression models were used to estimate the hazard ratio (HR) for the outcome.

RESULTS

The incidence rate (per 100 person-months) of critical COVID-19 was the lowest in the MHNW group (0.90), followed by the MHO (1.64), MUNW (3.37), and MUO (3.37) groups. Compared with MHNW, a significantly increased risk of critical COVID-19 was observed in MUNW (HR, 1.41; 95% CI, 1.01-1.98) and MUO (HR, 1.77; 95% CI, 1.39-2.44) but not in MHO (HR, 1.48; 95% CI, 0.98-2.23). The risk of ICU admission or IMV/ECMO was increased only in MUO; however, the risk of death was significantly higher in MUNW and MUO. The risk of critical COVID-19 increased insignificantly by 2% per 1 kg/m² BMI increase but significantly by 13% per 1 metabolically unhealthy component increase, even after mutually adjusting for BMI and metabolic health status.

CONCLUSIONS

Metabolic health is more important to COVID-19 outcomes than obesity itself, suggesting that metabolic health status should be considered for a precise and tailored management of COVID-19 patients.

Post-traumatic stress disorder and its association with stroke and stroke risk factors: A literature review

Stroke is a major cause of mortality and disability globally that has multiple risk factors. A risk factor that has recently gained more attention is post-traumatic stress disorder (PTSD). Literature searches were carried out for updated PTSD information and for the relationship between PTSD and stroke. The review was divided into two sections, one exploring PTSD as an independent risk factor for stroke, with a second concentrating on PTSD's influence on stroke risk factors. The study presents accumulating evidence that shows traumatic stress predicts stroke and is also linked to many major stroke risk factors. The review contributes knowledge to stroke aetiology and acts as a reference for understanding the relationship between PTSD and stroke. The information presented indicates that screening and identification of traumatic experience would be beneficial for directing stroke patients to appropriate psychological and lifestyle interventions. In doing so, the burden of stroke may be reduced worldwide.

Sex-specific prevalence, inequality and associated predictors of hypertension, diabetes, and comorbidity among Bangladeshi adults: results from a nationwide cross-sectional demographic and health survey

OBJECTIVES

To determine the sex-specific prevalence, inequality and factors associated with healthcare utilisation for diabetes mellitus (DM), hypertension and comorbidity among the adult population of Bangladesh.

STUDY DESIGN

This study analysed cross-sectional nationwide Bangladesh Demographic and Health Survey data from 2011. Comorbidity was defined as the coexistence of both DM and hypertension. Several socioeconomic and demographic factors such as age, sex, education, geographic location, administrative division, employment status, education and wealth index were considered as major explanatory variables. Inequality in prevalence and healthcare utilisation was measured using the 'Lorenz curve'. Adjusted multiple logistic regression models were performed to observe the effects of different factors and reported as adjusted ORs (AORs) with 95% CIs. A p value of <0.05 was adopted as the level of statistical significance.

SETTING

The study was conducted in Bangladesh.

PARTICIPANTS

A total of 7521 adult participants with availability of biomarkers information were included.

RESULTS

The mean age of the study participants was 51.4 years (SD ±13.0). The prevalence of hypertension, diabetes and comorbidity were 29.7%, 11.0% and 4.5% respectively. Socioeconomic inequality was observed in the utilisation of healthcare services. A higher prevalence of hypertension and comorbidity was significantly associated with individuals aged >70 years (AOR 7.0, 95% CI 5.0 to 9.9; AOR 6.7, 95% CI 3.0 to 14.9). The risk of having hypertension, diabetes and comorbidity were significantly higher among more educated, unemployed as well as among individuals from Khulna division.

CONCLUSIONS

The study revealed a rising prevalence of hypertension, diabetes and comorbidity with inequality in service utilisation. A joint effort involving public, private and non-governmental organisations is necessary to ensure improved accessibility in service utilisation and to reduce the disease burden.

Erigeron annuus (L.) Pers. Extract Inhibits Reactive Oxygen Species (ROS) Production and Fat Accumulation in 3T3-L1 Cells by Activating an AMP-Dependent Kinase Signaling Pathway

Obesity is one of the major public health problems in the world because it is implicated in metabolic syndromes, such as type 2 diabetes, hypertension, and cardiovascular diseases. The objective of this study was to investigate whether Erigeron annuus (L.) Pers. (EAP) extract suppresses reactive oxygen species (ROS) production and fat accumulation in 3T3-L1 cells by activating an AMP-dependent kinase (AMPK) signaling pathway. Our results showed that EAP water extract significantly inhibits ROS production, adipogenesis, and lipogenesis during differentiation of 3T3-L1 preadipocytes. In addition, EAP decreased mRNA and protein levels of proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα). Moreover, EAP suppressed mRNA expressions of fatty acid synthase (FAS), lipoprotein lipase (LPL), adipocyte protein 2 (aP2) in a dose-dependent manner. Whereas, EAP upregulated adiponectin expression, phosphorylation levels of AMPK and carnitine palmitoyltransferase 1 (CPT-1) protein level during differentiation of 3T3-L1 preadipocytes. These results suggest that EAP water extract can exert ROS-linked anti-obesity effect through the mechanism that might involve inhibition of ROS production, adipogenesis and lipogenesis via an activating AMPK signaling pathway.

General obesity and Cardiovascular diseases among Gaur Brahmin population of NCR/Delhi

AIMS

Cardiovascular diseases are one of the leading causes of mortality and morbidity among human beings. The presence of endemic Cardiovascular diseases and their risk factors differ from population to population. The Cardiovascular diseases associated risk factors are sub-categorised into two forms, one is traditional and the other is non-traditional risk factors. The present study shows the prevalence of both risk factors and its association with Cardiovascular diseases, especially with reference to general obesity.

MATERIALS AND METHODS

The present study includes a total of 506 Gaur Brahmins residing in Delhi and National Capital Region India. Household survey was conducted and data were collected by using pre-tested interview schedule. Somatometric measurements were taken following the international standard techniques. Approx 5 ml blood was collected from each individual unrelated up to the first cousion. The serum was used to analyse the lipid profiles and fasting glucose level. All necessary statistical analyses were performed using the Statistical Package for Social Sciences (SPSS) and MS Excel. The ethical clearance was obtained from the Ethical Committee of the Department of Anthropology, University of Delhi, Delhi.

RESULTS AND CONCLUSION

The mean value of Somatometric variables such as Body Mass Index, Waist circumference and Waist-hip ratio and physiological variables DBP and SBP (diastolic blood pressure and systolic blood pressure) were found to be higher than their respective ranges in the studied population. General obesity, though found to be less common in this population as compared to abdominal obesity, but it is found to be contributing to dyslipidemia.

Religious Attendance and Body Mass: An Examination of Variations by Race and Gender

Studies of the association between religious attendance and body mass have yielded mixed results. In this paper, we consider intersectional variations by race and gender to advance our understanding of these inconsistencies. We use data from the 2006-2008 Health and Retirement Study to examine the association between religious attendance and three indicators of body mass: overall body mass index, waist circumference, and waist-to-height ratio (n = 11,457). For White women, attendance is either protective or unrelated to body mass. For Black women, attendance is consistently associated with increased body mass. We find that religious attendance is not associated with body mass among the men.

The macrophage activation product sCD163 is associated with a less favourable metabolic profile in prepubertal children

OBJECTIVE

Macrophages are known to be involved in low-grade inflammatory processes such as obesity. soluble cluster of differentiation 163 (sCD163) is shed from the cell surface as specific macrophage activation marker. In prepubertal children, we studied if circulating sCD163 is associated with metabolic and cardiovascular risk markers.

METHODS

A population of 236 school-aged Caucasian children (111 girls and 125 boys) aged 8 ± 1 year [81 normal weight (body mass index [BMI]-SDS < 1); 74 overweight (1 ≤ BMI-standard deviation score [SDS] < 2) and 81 with obesity (BMI-SDS ≥ 2)] were studied. BMI, waist circumference, fat mass and visceral fat were measured. Fasting serum sCD163, homeostatic model assessment of insulin resistance, high sensitivity C-reactive protein, gamma-glutamyl transpeptidase and lipids were quantified.

RESULTS

Circulating sCD163 concentrations were higher in children with obesity (p < 0.0001). Associations were observed between circulating sCD163 and a less favourable metabolic profile as judged by higher waist circumference, fat mass, visceral fat, epicardial fat, homeostatic model assessment of insulin resistance, high sensitivity C-reactive protein, gamma-glutamyl transpeptidase and triglycerides (all between r = 0.173 and r = 0.363; p < 0.05 to p < 0.0001) and lower high-density lipoprotein-cholesterol (r = -0.285, p < 0.0001). In multiple regression analyses, circulating sCD163 was independently associated with HOMA-IR (β = 0.162, p = 0.016; model R²  = 0.179) and high density lipoprotein-cholesterol/triglycerides ratio (β = -0.167, p = 0.012; model R²  = 0.209).

CONCLUSIONS

Childhood obesity may increase the risk of developing metabolic diseases later in life through chronic macrophage activation having deleterious effects on metabolism.

Review: Renin-angiotensin-aldosterone system intervention in the cardiometabolic syndrome and cardio-renal protection

The metabolic syndrome, also known as the cardiometabolic syndrome (CMS), is a state of metabolic and vascular dysregulation that is associated with activation of the renin-angiotensin-aldosterone system (RAAS). Clinical components of the CMS include central or visceral obesity, hypertension (HTN), dyslipidemia, insulin resistance/hyperinsulinemia, and microalbuminuria that collectively convey increases in oxidative stress, inflammation, and subsequent endothelial dysfunction. The cardio-renal inflammation and oxidative stress enhanced in the CMS increases the risk for cardiovascular disease (CVD) and renal disease end-points such as stroke, congestive heart failure, and chronic kidney disease (CKD). The development of proteinuria is known to herald progressive kidney disease (e.g. CKD) and both are now well accepted as CVD risk factors. Evidence suggests a role for visceral obesity, insulin resistance/hyperinsulinemia, HTN, and other components of the CMS lead to an increased risk for proteinuria and progressive loss of renal function. Intervention with agents that block the RAAS (e.g. ACE inhibitors and Angiotensin type 1 receptor blockers) have been shown to reduce proteinuria, CKD progression, and CVD events. Herein, we will examine the relationship between RAAS intervention and reductions in CKD and CVD events.

Reducing Disparities in Hypertension Control: A Community-Based Hypertension Control Project (CHIP) for an Ethnically Diverse Population

The Community Hypertension Intervention Project (CHIP) is investigating medical, environmental, and psychosocial factors related to adherence to treatment for hypertension and examining the efficacy of three interventions designed to improve treatment adherence in a high-risk, underserved, ethnically diverse population. There were 1,367 Black (76%) and Hispanic (21%) adults who participated in a 4-year longitudinal study. Participants were randomized to either usual care or one of three interventions: (a) individualized counseling sessions with community health workers (CHWs), (b) a computerized appointment tracking system, or (c) home visits/focus group discussions with CHWs. At baseline, a total of 33% of the participants had one or more comorbidities in addition to hypertension; only 35% had their blood pressure under control. Participants assigned to the patient tracking intervention exhibited the most significant improvement in appointment keeping and blood pressure control status at 6 months; however, the 12-month follow-up assessments indicated that individualized counseling and home visits resulted in significant, sustained improvements in appointment keeping and blood pressure control status. These findings are now being integrated into the patient care delivery system of the participating outpatient clinics.

Transgenic Mice Overexpressing Serum Retinol-Binding Protein Develop Progressive Retinal Degeneration through a Retinoid-Independent Mechanism

Serum retinol-binding protein 4 (RBP4) is the sole specific transport protein for retinol in the blood, but it is also an adipokine with retinol-independent, proinflammatory activity associated with obesity, insulin resistance, type 2 diabetes, and cardiovascular disease. Moreover, two separate studies reported that patients with proliferative diabetic retinopathy have increased serum RBP4 levels compared to patients with mild or no retinopathy, yet the effect of increased levels of RBP4 on the retina has not been studied. Here we show that transgenic mice overexpressing RBP4 (RBP4-Tg mice) develop progressive retinal degeneration, characterized by photoreceptor ribbon synapse deficiency and subsequent bipolar cell loss. Ocular retinoid and bisretinoid levels are normal in RBP4-Tg mice, demonstrating that a retinoid-independent mechanism underlies retinal degeneration. Increased expression of pro-interleukin-18 (pro-IL-18) mRNA and activated IL-18 protein and early-onset microglia activation in the retina suggest that retinal degeneration is driven by a proinflammatory mechanism. Neither chronic systemic metabolic disease nor other retinal insults are required for RBP4 elevation to promote retinal neurodegeneration, since RBP4-Tg mice do not have coincident retinal vascular pathology, obesity, dyslipidemia, or hyperglycemia. These findings suggest that elevation of serum RBP4 levels could be a risk factor for retinal damage and vision loss in nondiabetic as well as diabetic patients.

Overnutrition, mTOR signaling, and cardiovascular diseases

The prevalence of obesity and associated medical disorders has increased dramatically in the United States and throughout much of the world in the past decade. Obesity, induced by excess intake of carbohydrates and fats, is a major cause of Type 2 diabetes, hypertension, and the cardiorenal metabolic syndrome. There is emerging evidence that excessive nutrient intake promotes signaling through the mammalian target of rapamycin (mTOR), which, in turn, may lead to alterations of cellular metabolic signaling leading to insulin resistance and obesity-related diseases, such as diabetes, cardiovascular and kidney disease, as well as cancer. While the pivotal role of mTOR signaling in regulating metabolic stress, autophagy, and adaptive immune responses has received increasing attention, there remain many gaps in our knowledge regarding this important nutrient sensor. For example, the precise cellular signaling mechanisms linking excessive nutrient intake and enhanced mTOR signaling with increased cardiovascular and kidney disease, as well as cancer, are not well understood. In this review, we focus on the effects that the interaction between excess intake of nutrients and enhanced mTOR signaling have on the promotion of obesity-associated diseases and potential therapeutic strategies involving targeting mTOR signaling.

Coronary Heart Disease in Postmenopausal Women with Type II Diabetes Mellitus and the Impact of Estrogen Replacement Therapy: A Narrative Review

Coronary heart disease is the main cause of death in postmenopausal women (PMW); moreover its mortality exceeds those for breast cancer in women at all ages. Type II diabetes mellitus is a major cardiovascular risk factor and there is some evidence that the risk conferred by diabetes is greater in women than in men. It was established that the deficiency of endogenous estrogens promotes the atherosclerosis process. However, the impact of estrogen replacement therapy (ERT) on cardiovascular prevention remains controversial. Some authors strongly recommend it, whereas others revealed a concerning trend toward harm. This review tries to underlines the different components of cardiovascular risk in diabetic PMW and to define the place of ERT.

Obesity (Sometimes) Matters: The Importance of Context in the Relationship between Obesity and Life Satisfaction

Previous research has established the negative influence of obesity on subjective well-being. In the present work, the authors use multilevel modeling and Behavior Risk Factor Surveillance System data (N = 1,319,340) to examine how this relationship is influenced by the prevalence of obesity in the contexts in which individuals are living and how such relationships vary by gender. The results suggest that some of the influence of obesity on life satisfaction is the result of relative comparison. Implications for both our understanding of the growing "obesity epidemic" and the study of subjective well-being are discussed.

Metformin in peritoneal dialysis: a pilot experience

OBJECTIVE

In a number of patients, the antidiabetic drug metformin has been associated with lactic acidosis. Despite the fact that diabetes mellitus is the most common cause of end-stage renal disease (ESRD) and that peritoneal dialysis (PD) is an expanding modality of treatment, little is known about optimal treatment strategies in the large group of PD patients with diabetes. In patients with ESRD, the use of metformin has been limited because of the perceived risk of lactic acidosis or severe hypoglycemia. However, metformin use is likely to be beneficial, and PD might itself be a safeguard against the alleged complications.

METHODS

Our study involved 35 patients with insulin-dependent type 2 diabetes [median age: 54 years; interquartile range (IQR): 47-59 years] on automated PD (APD) therapy. Patients with additional risk factors for lactic acidosis were excluded. Metformin was introduced at a daily dose in the range 0.5 - 1.0 g. All patients were monitored for glycemic control by blood sugar levels and HbA1c. Plasma lactic acid levels were measured weekly for 4 weeks and then monthly to the end of the study. Plasma and effluent metformin and plasma lactate levels were measured simultaneously.

RESULTS

In this cohort, the median duration of diabetes was 18 years (IQR: 14 - 21 years), median time on PD was 31 months (IQR: 27 - 36 months), and median HbA1c was 6.8% (IQR: 5.9% - 6.9%). At metformin introduction and at the end of the study, the median anion gap was 11 mmol/L (IQR: 9 - 16 mmol/L) and 12 mmol/L (IQR: 9 - 16 mmol/L; p > 0.05) respectively, median pH was 7.33 (IQR: 7.32 - 7.36) and 7.34 (IQR: 7.32 - 7.36, p > 0.05) respectively, and mean metformin concentration in plasma and peritoneal fluid was 2.57 ± 1.49 mg/L and 2.83 ± 1.7 mg/L respectively. In the group overall, mean lactate was 1.39 ± 0.61 mmol/L, and hyperlactemia (>2 mmol/L to 5 mmol/L) was found in 4 of 525 plasma samples (0.76%), but the patients presented no symptoms. None of the patients registered a plasma lactate level above 5 mmol/L. We observed no correlation between plasma metformin and plasma lactate (r = 0.27).

CONCLUSIONS

Metformin may be used with caution in APD patients with insulin-dependent type 2 diabetes. Although our study demonstrated the feasibility of metformin use in APD, it was not large enough to demonstrate safety; a large-scale study is needed.

Prenatal Exposure to Nicotine Causes Postnatal Obesity and Altered Perivascular Adipose Tissue Function

OBJECTIVE

Recent epidemiological studies have shown that there is an increased risk of obesity and hypertension in children born to women who smoked during pregnancy. The aim of this study was to examine the effect of fetal and neonatal exposure to nicotine, the major addictive component of cigarette smoke, on postnatal adiposity and blood vessel function.

RESEARCH METHODS AND PROCEDURES

Female Wistar rats were given nicotine or saline (vehicle) during pregnancy and lactation. Postnatal growth was determined in the male offspring from weaning until 26 weeks of age. At 26 weeks of age, fat pad weight and the function of the perivascular adipose tissue (PVAT) in the thoracic aorta and mesenteric arteries were examined.

RESULTS

Exposure to nicotine resulted in increased postnatal body weight and fat pad weight and an increased amount of PVAT in the offspring. Contraction of the aorta induced by phenylephrine was significantly attenuated in the presence of PVAT, whereas this effect was not observed in the aortic rings from the offspring of nicotine-exposed dams. Phenylephrine-induced contraction without PVAT was not different between saline- and nicotine-exposed rats. Transfer of solution incubated with PVAT-intact aorta to PVAT-free aorta induced a marked relaxation response in the rats from saline-exposed dams, but this relaxation response was significantly impaired in the rats from nicotine-exposed dams.

DISCUSSION

Our results showed that prenatal nicotine exposure increased adiposity and caused an alteration in the modulatory function of PVAT on vascular relaxation response, thus providing insight into the mechanisms underlying the increased prevalence of obesity and hypertension in children exposed to cigarette smoke in utero.

Aloe-emodin inhibits adipocyte differentiation and maturation during in vitro human mesenchymal stem cell adipogenesis

In this study, we examined the effects of Aloe-emodin (AE) on the inhibition of adipocyte differentiation during 3-isobutyl-1-methylxanthine (IBMX)-induced adipocyte differentiation in human mesenchymal stem cells (hMSCs). AE treatment (5, 10, and 20 µM) of preadipocyte cells resulted in a significant (p < 0.05) decrease in glycerol phosphate dehydrogenase and triglyceride levels as well as an increase in lactate dehydrogenase activity and attenuated lipid accumulation compared with untreated differentiated adipocytes. Using quantitative reverse transcription polymerase chain reaction, we studied the mRNA expression levels of resistin, adiponectin, aP(2), lipoprotein lipase, PPARγ, and tumor necrosis factor-α in hMSCs undergoing adipocyte differentiation; treatment with AE decreased the expression of these adipogenic genes and decreased adipocyte differentiation. In addition, AE suppresses the differentiation of hMSCs into adipocytes by downregulating PPARγ and C/EBPα expressions. AE significantly inhibited hMSCs proliferation and preadipocyte differentiation within the first 2 days of treatment, indicating that the antiadipogenic effect.

The role of metformin in the management of NAFLD

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder worldwide. Its prevalence ranges 10–24% in the general population, reaching 60–95% and 28–55% in obese and diabetic patients, respectively. Although the etiology of NAFLD is still unclear, several lines of evidences have indicated a pathogenetic role of insulin resistance in this disorder. This concept has stimulated several clinical studies where antidiabetic drugs, such as insulin sensitizers including metformin, have been evaluated in insulin-resistant, NAFLD patients. These studies indicate that metformin might be of benefit in the treatment of NAFLD, also in nondiabetic patients, when associated to hypocaloric diet and weight control. However, the heterogeneity of these studies still prevents us from reaching firm conclusions about treatment guidelines. Moreover, metformin could have beneficial tissue-specific effects in NAFLD patients irrespective of its effects as insulin sensitizer.

Enhancement of antioxidant defense mechanism by pitavastatin and rosuvastatin on obesity-induced oxidative stress in Wistar rats

CONTEXT

There has been a steady increase in the epidemiology of obesity over the last 30 years with developed countries leading the way. Oxidative stress was believed to be the principle contributor to the development of cardiovascular disorders that linked with obesity.

OBJECTIVE

To evaluate the enhancement of antioxidant defense mechanism by Pitavastatin (PTV) and Rosuvastatin (RSV) on obesity-induced oxidative stress in Wistar rats.

METHODS

Fifty Wistar albino rats were divided into five groups. High fat diet (HFD, 20 g/day/rat) pellets were given for 28 days to produce obesity-induced oxidative stress in Wistar rats. Oral administration of HFD along with PTV, RSV and Orlistat [(HFD for 28 days + from 8th day PTV (1 mg/kg), RSV (5 mg/kg) and Orlistat (10 mg/kg) to 28th day] were given respectively.

RESULTS

Both PTV and RSV produced significant (p < 0.01) reduction in serum apolipoprotein-B (Apo-B), total cholesterol (TC), triglycerides (TGs), cardiac-lipid peroxides (TBARS) levels and elevation in serum high density lipoprotein (HDL-C), cardiac antioxidant enzymes [glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catase (CAT)] levels.

DISCUSSION AND CONCLUSION

Results were comparable with Orlistat, a standard antiobesity drug and present initial evidence that Pitavastatin and Rosuvastatin are useful for the treatment of obesity by enhancing the antioxidant defense mechanism. However, the effects of PTV were more prominent than RSV. The present findings of Pitavastatin and Rosuvastatin raise the possibility of a new application as an antiobesity therapeutic modality.

The functional changes of the perivascular adipose tissue in spontaneously hypertensive rats and the effects of atorvastatin therapy

The aim of this study was to examine the function of perivascular adiposa tissue (PVAT) on vascular relaxation response in spontaneously hypertensive rats (SHR) and the modulatory effects of the atorvastatin therapy on the PVAT functions. We investigated the mechanisms of the perivascular adipocyte-derived relaxation factor (PVRF) by using isolated rat's aortic rings and isometric contraction measurements. We found that contraction of the thoracic aorta induced by phenylephrine was significantly attenuated in the presence of PVAT from normotensive Wistar-Kyoto rats (WKY group) or the spontaneously hypertensive rats treated with atorvastatin (SHR-A group, atorvastatin 50mg/kg/day), whereas this effect was not observed in the thoracic aortic rings from the control SHR (SHR group). Transferring the solution incubated with PVAT-intact thoracic aorta to PVAT-free thoracic aorta, it induced a remarkable relaxation response in the WKY but not in the control SHR. Tetraethylammoniumchloride (TEA) could block the above relaxation. It was also shown that the PVRF function was likely, depending on the extracellular [Ca(2+)]; the anti-contractile effect of PVAT could be reduced by the inhibitor of the adenosine triphosphate (ATP)-dependent potassium channels, glibenclamide, and could be reduced by the inhibitor of cyclooxygenase by indomethacin. We thus infer that the PVAT function was distorted in hypertension rats, and the lipid-lowering treatment with atorvastatin could restore the PVAT function. The function of the PVRF may involve the Ca(2+)-activated potassium channels, the ATP-dependent potassium channels in vascular smooth muscle cell (SMC), and the release of PVRF from PVAT may involve prostaglandins (PGs) and the calcium metabolism. These results provide an insight into the pathological mechanisms of hypertension development, and indicate that the PVAT may be a potential new target for the hypertensive therapy.

Interactions between lipoproteins and platelet membranes in obesity

The aim was to investigate low-density lipoprotein (LDL) composition and Na(+)/K(+) adenosine triphosphatase (ATPase) and Ca(2+) ATPase activities and membrane fluidity measured by 1-(4-trimethylaminophenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH) in platelets from obese patients and controls in order to identify, if any, platelet membrane's chemical-physical and/or functional modifications associated with compositional modification of circulating lipoproteins. Moreover, we studied the in vitro effect on both platelet transmembrane cationic transport and fluidity, by incubating LDL from 30 obese subjects with platelets from 30 control subjects. The analysis of the chemical composition of LDL from obese patients showed a significant increase in the percent content of total cholesterol (TC) and triglycerides (TGs) and in the mean levels of lipid hydroperoxides compared to controls' LDL. Platelet Na(+)/K(+) ATPase and Ca(2+) ATPase activities showed, respectively, a significant decrease and increase in patients compared to controls; minor significant, respectively, decreases and increases are shown also in control platelets incubated with LDL from obese patients. Anisotropy tested with TMA-DPH probe was significantly increased both in platelets from obese patients and in control platelets incubated with LDL from obese patients compared to control platelets. This study highlights that obesity induces remarkable modifications both in lipoproteins and platelets. Both platelet hyperfunction and quantitative/qualitative alterations in plasma lipoproteins, as well as an altered interaction between circulating lipoproteins and platelets, might play a relevant role in the increased prevalence of the early atherosclerotic lesions development in obese subjects. The present data point out that obesity might represent a major potentially modifiable risk factor for the onset of numerous complications, in particular cardiovascular ones.

Inflammatory markers and visceral fat are inversely associated with maximal oxygen consumption in women with polycystic ovary syndrome (PCOS)

BACKGROUND

We investigated whether several different inflammatory markers including C-reactive protein (CRP) and fibrinogen and white blood cells (WBCs) count, are associated with maximal oxygen consumption (VO(2 max)) in women with polycystic ovary syndrome (PCOS).

METHODS

In PCOS women (n = 124, 24.1 +/- 4.5 year-old) VO(2 max) was measured during symptom-limited cardiopulmonary exercise test. Abdominal fat distribution was determined by ultrasound. Physical activity level was assessed by a standardized questionnaire. CRP was measured by immunoassays, fibrinogen by the Clauss method, and WBCs count with a Coulter counter.

RESULTS

Pearson's analysis showed a significant correlation between VO(2 max) and logCRP (r = -0.437, P < 0.001), fibrinogen (r = -0.479, P < 0.001), and WBCs count (r = -0.438, P < 0.001). Multivariable logistic regression model showed that age (beta = -0.127, P = 0.005), AUC(INS )(beta = -0.335, P < 0.001), HDL-C (beta = 0.390, P < 0.001), physical activity score (beta = 0.238, P = 0.002), visceral fat (beta =-0.184), P = 0.023), FAI (beta = -0.291, P = 0.028); CRP (beta = -0.216, P = 0.011), fibrinogen (beta = -0.113, P = 0.008) and WBCs count (beta = -0.177, P < 0.001) were significantly associated with VO(2 max).

CONCLUSIONS

Acute-phase reactants, such as CRP and fibrinogen, and WBCs count were independently and inversely associated with a direct measure of cardiorespiratory fitness (VO(2 max)) in women with PCOS, even after adjustment for physical activity level and other potential confounding factors. These findings add to the growing body of evidence linking inflammation to cardiorespiratory fitness in PCOS women.

Changes induced by dietary energy intake and divergent selection for muscle fat content in rainbow trout (Oncorhynchus mykiss), assessed by transcriptome and proteome analysis of the liver

BACKGROUND

Growing interest is turned to fat storage levels and allocation within body compartments, due to their impact on human health and quality properties of farm animals. Energy intake and genetic background are major determinants of fattening in most animals, including humans. Previous studies have evidenced that fat deposition depends upon balance between various metabolic pathways. Using divergent selection, we obtained rainbow trout with differences in fat allocation between visceral adipose tissue and muscle, and no change in overall body fat content. Transcriptome and proteome analysis were applied to characterize the molecular changes occurring between these two lines when fed a low or a high energy diet. We focused on the liver, center of intermediary metabolism and the main site for lipogenesis in fish, as in humans and most avian species.

RESULTS

The proteome and transcriptome analyses provided concordant results. The main changes induced by the dietary treatment were observed in lipid metabolism. The level of transcripts and proteins involved in intracellular lipid transport, fatty acid biosynthesis and anti-oxidant metabolism were lower with the lipid rich diet. In addition, genes and proteins involved in amino-acid catabolism and proteolysis were also under expressed with this diet. The major changes related to the selection effect were observed in levels of transcripts and proteins involved in amino-acid catabolism and proteolysis that were higher in the fat muscle line than in the lean muscle line.

CONCLUSION

The present study led to the identification of novel genes and proteins that responded to long term feeding with a high energy/high fat diet. Although muscle was the direct target, the selection procedure applied significantly affected hepatic metabolism, particularly protein and amino acid derivative metabolism. Interestingly, the selection procedure and the dietary treatment used to increase muscle fat content exerted opposite effects on the expression of the liver genes and proteins, with little interaction between the two factors. Some of the molecules we identified could be used as markers to prevent excess muscle fat accumulation.

Effect of pioglitazone on heart function and N-terminal pro-brain natriuretic peptide levels of patients with type 2 diabetes

We assessed the effect of the addition of pioglitazone on metabolic control and heart function of patients with type 2 diabetes already receiving sulfonylurea plus metformin. Forty-four patients were given 30 mg of pioglitazone for 3 months. Physical examination, laboratory tests including N-terminal pro-brain natriuretic peptide (NT-proBNP), and echocardiography, were performed at baseline and at study completion. Target HbA(1c) levels were achieved by 44.2% of the patients. Pioglitazone ameliorated lipid profile and lowered liver enzymes and C-reactive protein. Significant increases in NT-proBNP by 39% (P < 0.005) were noticed, but echocardiographic parameters were not altered, even in high-risk subgroups (patients older than 60 years, with diabetes for more than 10 years, with hypertension, with elevated baseline NT-proBNP levels, with left ventricular hypertrophy). In patients with a greater than 60% increase in NT-proBNP levels, a significant increase in left ventricular ejection fraction (P < 0.05) and in fractional shortening (P < 0.05) was found. None of the patients developed edema or signs or symptoms of heart failure. Triple oral combination antidiabetic treatment is an effective therapeutic strategy and weight gain does not abrogate its beneficial actions. Pioglitazone does not affect heart function and even though it increases NT-proBNP, this appears to represent a reaction to volume overload.

Dietary interaction of high fat and marginal copper deficiency on cardiac contractile function

OBJECTIVE

High-fat and marginally copper-deficient diets impair heart function, leading to cardiac hypertrophy, increased lipid droplet volume, and compromised contractile function, resembling lipotoxic cardiac dysfunction. However, the combined effect of the two on cardiac function is unknown. This study was designed to examine the interaction between high-fat and marginally copper-deficient diets on cardiomyocyte contractile function.

RESEARCH METHODS AND PROCEDURES

Weanling male rats were fed diets incorporating a low- or high-fat diet (10% or 45% of kcal from fat, respectively) with adequate (6 mg/kg) or marginally deficient (1.5 mg/kg) copper content for 12 weeks. Contractile function was determined with an IonOptix system including peak shortening (PS), time-to-PS, time-to-90% relengthening, maximal velocity of shortening/relengthening, and intracellular Ca(2+) ([Ca(2+)](I)) rise and decay.

RESULTS

Neither dietary treatment affected blood pressure or glucose levels, although the high-fat diet elicited obesity and glucose intolerance. Both diets depressed PS, maximal velocity of shortening/relengthening, and intracellular Ca(2+) ([Ca(2+)](I)) rise and prolonged time-to-90% relengthening and Ca(2+) decay without an additive effect between the two. Ca(2+) sensitivity, apoptosis, lipid peroxidation, nitrosative damage, tissue ceramide, and triglyceride levels were unaffected by either diet or in combination. Phospholamban (PLB) but not sarco(endo)plasmic reticulum Ca(2+)-ATPase was increased by both diets. Endothelial NO synthase was depressed with concurrent treatments. The electron transport chain was unaffected, although mitochondrial aconitase activity was inhibited by the high-fat diet.

DISCUSSION

These data suggest that high-fat and marginally copper deficient diets impaired cardiomyocyte contractile function and [Ca(2+)](i) homeostasis, possibly through a similar mechanism, without obvious lipotoxicity, nitrosative damage, and apoptosis.

Cardiovascular complications of obesity in adolescents

Obesity is an increasingly important worldwide health problem, representing the major risk factor for coronary heart disease. The increase in the prevalence of obesity, particularly among younger age groups, is likely to have long-term implications for cardiovascular disease (CVD) in the years to come, especially at a young age. Obesity plays a central role in the insulin resistance (IR) syndrome and increases the risk of atherosclerotic CVD. The present review will examine the relationships among cardiovascular risk (CVR) factors during the childhood-adolescence-adulthood transition. In fact, the relation between obesity, in particular visceral obesity and CVD, appears to develop at a relatively young age. The foremost physical consequence of obesity is atherosclerotic CVD, and an intriguing example of obesity-related cardiovascular complications affecting young women is the polycystic ovary syndrome (PCOS).

Type 2 diabetes mellitus is a risk factor for the development of hypertension in postmenopausal women

OBJECTIVE

Hypertension and type 2 diabetes mellitus are common diseases that are frequently found concomitantly in postmenopausal women. These findings suggest a close and/or synergistic nature in the relationship between the two disease processes; however, no prospective data exist on the incidence rate of hypertension in postmenopausal women with type 2 diabetes mellitus.

METHODS

The present study assessed the risk of developing hypertension in 840 postmenopausal women: 102 women (12.1% of the cohort) with type 2 diabetes mellitus and 738 (87.9%) free of diabetes. The mean +/- SD follow-up was 3.2 +/- 0.9 years (range 0.5-6.0 years).

RESULTS

The incidence rate (cases of hypertension per 100 person-years) was 1.1 for the group of women without diabetes versus 5.6 in women with diabetes (P < 0.0001). Compared with the non-diabetic group, women with type 2 diabetes mellitus had a statistically significant higher risk of developing hypertension. The relative risks for women with diabetes was 5.09 [crude: 95% confidence interval (CI) = 3.52-7.36; P < 0.0001]; 3.43 (adjusted for body mass index and waist circumference: 95% CI = 2.25-5.14; P < 0.001); and 2.95 (adjusted for all potential confounders: 95% CI = 1.86-4.32; P < 0.01).

CONCLUSION

In our prospective study, on the incidence of hypertension, the presence of type 2 diabetes was found to be a potent independent risk determinant. This suggests that postmenopausal women affected by type 2 diabetes mellitus comprise a population at high risk for the subsequent development of hypertension.

High-fat diet-induced juvenile obesity leads to cardiomyocyte dysfunction and upregulation of Foxo3a transcription factor independent of lipotoxicity and apoptosis

BACKGROUND

Obesity is associated with dyslipidemia, which leads to elevated triglyceride and ceramide levels, apoptosis and compromised cardiac function.

METHODS

To determine the role of high-fat diet-induced obesity on cardiomyocyte function, weanling male Sprague-Dawley rats were fed diets incorporating 10% of kcal or 45% of kcal from fat. Mechanical function of ventricular myocytes was evaluated including peak shortening (PS), time-to-PS (TPS), time-to-90% relengthening (TR90) and maximal velocity of shortening and relengthening (+/- dl/dt). Intracellular Ca properties were assessed using fluorescent microscopy.

RESULTS

High-fat diet induced hyperinsulinemic insulin-resistant obesity with depressed PS, +/- dl/dt, prolonged TPS/TR90 reduced intracellular Ca release and Ca clearing rate in the absence of hypertension, diabetes, lipotoxicity and apoptosis. Myocyte responsiveness to increased stimulus frequency and extracellular Ca was compromised. SERCA2a and phospholamban levels were increased, whereas phosphorylated phospholamban and potassium channel (Kv1,2) were reduced in high-fat diet group. High-fat diet upregulated the forkhead transcription factor Foxo3a, and suppressed mitochondrial aconitase activity without affecting expression of the caloric sensitive gene silent information regulator 2 (Sir2), protein nitrotyrosine formation, lipid peroxidation and apoptosis. Levels of endothelial nitric oxide synthase (NOS), inducible NOS, triglycerides and ceramide were similar between the two groups.

CONCLUSIONS

Collectively, our data show that high-fat diet-induced obesity resulted in impaired cardiomyocyte function, upregulated Foxo3a transcription factor and mitochondrial damage without overt lipotoxicity or apoptosis.

Leptin regulates cardiomyocyte contractile function through endothelin-1 receptor-NADPH oxidase pathway

Leptin, the obese gene product, plays an important role in the regulation of cardiac function. However, the mechanism behind leptin-induced cardiomyocyte contractile response is poorly understood. This study was designed to examine whether endothelin-1 receptor and NADPH oxidase play any role in leptin-induced cardiac contractile response. Isolated murine cardiomyocytes were exposed to leptin (5, 50, and 100 nmol/L) for 60 minutes in the absence or presence of the ETA receptor antagonist BQ123 (1 micromol/L), the ETB receptor antagonist BQ788 (1 micromol/L), or the NADPH oxidase inhibitor apocynin (100 micromol/L) before mechanical function was studied. Superoxide levels were measured by dihydroethidium fluorescent dye and the superoxide dismutase-inhibitable reduction of cytochrome c. NADPH oxidase subunit expression (p22phox, p47phox, p67phox, and gp91phox) was evaluated with Western blot. Leptin depressed peak shortening and maximal velocity of shortening/relengthening (+/-dL/dt), prolonged the duration of relengthening (TR90) without affecting the time-to-peak cell shortening. Consistent with the mechanical characteristics, myocytes treated with leptin displayed a reduced electrically stimulated rise in intracellular Ca2+ (change in fura-2 fluorescence intensity) associated with a prolonged intracellular Ca2+ decay rate. All of the abnormalities were significantly attenuated by apocynin, BQ123, or BQ788. Intracellular superoxide generation was enhanced after leptin treatment, which was partially blocked by apocynin, BQ123, or BQ788. Leptin had no effect on p22phox and gp91phox but upregulated protein expression of p67phox and p47phox, both of which were inhibited by apocynin, BQ123, or BQ788. These results suggest that leptin suppresses cardiac contractile function in ventricular myocytes through the endothelin-1 receptor and NADPH oxidase-mediated pathway.

Cardiovascular risk factors in minorities

Recent clinical trials have confirmed the value of intervention on major risk factors, particularly hypertension and hyperlipidemia, in preventing the progression and clinical sequelae of atherosclerosis. Less is known about the prevalence and impact of atherosclerosis risk factors in minorities. A review of recent literature reporting the prevalence of established and new predictors of atherosclerotic events in minority populations and the inclusion of minorities in clinical trials is presented. The prevalence of risk factors differs considerably in minority populations. The role of "premature" coronary death and the level of some risk factors, particularly obesity and blood pressure in African descendants and high triglycerides, low high-density lipoproteins, and diabetes in some Hispanics, is higher than in whites. With few exceptions, however, minorities have not been included in clinical trials in sufficient numbers to determine whether significant differences in the benefit of risk factor intervention exists. Prevalence of key risk factors differs among minority groups. Risk factor intervention should be pursued in minority groups but with the understanding that clinical trials have not ruled out the possibility of qualitative or quantitative differences in response rates among different groups.

Diabetes in the elderly and in women: cardiovascular risks

The prevalence of diabetes in the United States is on the rise because of changing characteristics of our population. Ours is an aging population; women who are older than 75 years constitute the fastest growing segment of our population. Our population is increasingly more overweight and sedentary and the numbers of minority persons who have a higher prevalence of obesity and diabetes are on the rise. Currently, at least 17 million persons have known diabetes; another 4 million have the disease but have not been diagnosed. There also is a much larger population-perhaps up to 60 million per-sons-who has the metabolic syndrome. Up to 60% of persons who have essential hypertension have impaired insulin resistance and other characteristics of this syndrome. This article focuses on the metabolic syndrome and diabetes in women and the elderly.

Role of exercise training on cardiovascular disease in persons who have type 2 diabetes and hypertension

Exercise training is an essential component in the medical management of patients who have type 2 diabetes and hypertension. Regular exercise improves the cardiovascular health of individuals who have these conditions through multiple mechanisms (Fig. 1). These mechanisms include improvements in endothelial vasodilator function,left ventricular diastolic function, arterial stiffness.systematic inflammation, and reducing left ventricular mass. Exercise training also reduces total and abdominal fat, which mediate improvements in insulin sensitivity and blood pressure, and possibly, endothelial function. Persons who are in a prediabetic stage or those who have the metabolic syndrome may be able to prevent or delay the progression to overt diabetes by adopting a healthier lifestyle, of which increasing habitual levels of physical activity isa vital component. Most persons who have diabetes and hypertension or are at risk for these conditions should be able to initiate an exercise program safely after appropriate medical screen-ing and the establishment of an individualized exercise prescription. Despite the increasing amount of evidence that shows the benefits of exercise training, this modality of prevention and treatment continues to be underused. Although patients' lack of knowledge of the benefits of exercise or lack of motivation contributes to this underuse, a lack of clear and specific guidelines from health care professionals also is an important factor. Clinicians need to educate patients about the benefits of exercise for managing their type 2 diabetes and assist in formulating specific advice for increasing physical activity. Specific instructions should be given to patients, rather than general advice, such as "you should exercise more often." Many cardiac re-habilitation and clinical exercise programs can accommodate patients who have type 2 diabetes and hypertension. Such programs can establish individualized exercise prescriptions and provide an environment that is conducive for "lifestyle change" that underlies long-term compliance to exercise and risk factor modification.

Obesity and cardiovascular risk: the new public health problem of worldwide proportions

Obesity could be considered a new global health epidemic above all others, especially when it is characterized by central fat distribution. This is illustrated by dramatic provisional data, indicating a continuous increase in the trend of overweight and obese individuals in several countries, including the USA and countries in Europe. Several epidemiological, pathophysiological and clinical studies clearly indicate that two of the major independent risk factors for cardiovascular disease or events are being overweight, and obesity. Accordingly, weight loss and prevention of weight gain has to be considered one of the most important strategies to reduce the incidence of cardiovascular disease.

Insulin and insulin resistance: impact on blood pressure and cardiovascular disease

Cardiovascular disease is a major cause of mortality in individuals with diabetes. Many factors, including hypertension, contribute to the high prevalence of CVD in this population. Hypertension occurs approximately twice as frequently in patients with diabetes compared with patients without diabetes. Conversely, recent data suggest that hypertensive persons are more likely to develop diabetes than normotensive persons. In addition, up to 75% of CVD in patients with diabetes may be attributed to hypertension, leading to recommendations for more aggressive blood pressure control (ie, < 130/85 mm Hg) in persons with coexistent diabetes and hypertension. Increasing obesity further contributes to both diabetes and hypertension and significantly increases CVD morbidity and mortality. Other important risk factors for CVD in these patients include atherosclerosis, dyslipidemia, microalbuminuria, endothelial dysfunction, platelet hyperaggregability, coagulation abnormalities, and diabetic cardiomyopathy. The current knowledge regarding these risk factors has been reviewed, placing special emphasis on the metabolic syndrome, hypertension, microalbuminuria, and the role of obesity in these disorders. Although not discussed in detail, it is acknowledged that both hygienic measures (weight loss and aerobic exercise) and treatment strategies that include aspirin, statins, INS sensitizers, and antihypertensive agents that reduce renin-angiotensin-aldosterone system activity have been shown to reduce inflammation, coagulation abnormalities, endothelial function, proteinuria, and in some cases reduce CVD and renal disease progression. Additional therapeutic agents are currently being developed specifically to improve INS sensitivity and other CVD risk factors that are components of the cardiometabolic syndrome.

Obesity as a cardiovascular risk factor

The prevalence of overweight and obesity continues to increase rapidly in the United States, with more than half of all adults currently overweight or obese. In general, people become obese because of a combination of inherited genes and a lifestyle consisting of low levels of physical activity and consumption of excess calories. Obesity, especially the central or visceral type, is a predisposing factor for the development of type 2 diabetes mellitus, hypertension, and cardiovascular disease (CVD). Obesity and type 2 diabetes are associated with insulin resistance. The relation among obesity, insulin resistance, and CVD appears to develop at a relatively young age. Central obesity is linked with hyperinsulinemia, insulin resistance, dyslipidemia, and proinflammatory and prothrombotic clinical states. Adipose tissue synthesizes and secretes biologically active molecules that may affect CVD risk factors. These chemical messengers include adiponectin, resistin, leptin, plasminogen activator inhibitor-1, tumor necrosis factor-alpha, and interleukin-6. In overweight and obese individuals, weight loss may improve insulin sensitivity, leading to reduction in risk factors for CVD and, consequently, the potential for cardiovascular events. Agents that improve insulin sensitivity, such as the thiazolidinediones, have been shown to reduce visceral obesity. Decreases in visceral adipose tissue contribute to improvements in insulin sensitivity and blood pressure, and weight loss reduces serum levels of triglycerides and low-density lipoprotein cholesterol while increasing serum levels of high-density lipoprotein cholesterol. Reduction of risk factors suggests that the development of cardiovascular disease will be reduced by the improvement of insulin sensitivity and weight loss.

Alterations in nitric oxide-cGMP pathway in ventricular myocytes from obese leptin-deficient mice

Leptin is a regulator of body weight and affects nitric oxide (NO) production. This study was designed to determine whether the myocardial NO-cGMP signal transduction system was altered in leptin-deficient obese mice. Contractile function, guanylyl cyclase activity, and cGMP-dependent protein phosphorylation were assessed in ventricular myocytes isolated from genetically obese (B6.V-Lepob) and age-matched lean (C57BL/6J) mice. There were no differences in baseline contraction between the lean and obese groups. After stimulation with the NO donor S-nitroso-N-acetyl-penicillamine (SNAP, 10-6 and 10-5 M) or a membrane-permeable cGMP analog 8-bromo-cGMP (8-Br-cGMP, 10(-6) and 10(-5) M), cell contractility was depressed. However, 8-Br-cGMP had significantly greater effects in obese mice than in lean controls with percent shortening reduced by 47 vs. 39% and maximal rate of shortening decreased by 46 vs. 36%. The negative effects of SNAP were similar between the two groups. Soluble guanylyl cyclase activity was not attenuated. This suggests that the activity of the cGMP-independent NO pathway may be enhanced in obesity. The phosphorylated protein profile of cGMP-dependent protein kinase showed that four proteins were more intensively phosphorylated in obese mice, which suggests an explanation for the enhanced effect of cGMP. These results indicate that the NO-cGMP signaling pathway was significantly altered in ventricular myocytes from the leptin-deficient obese mouse model.

Change in body mass index from adolescence to young adulthood and increased carotid intima-media thickness at 28 years of age: The Atherosclerosis Risk in Young Adults study

Obesity has become a major health problem in Western societies by increasing the risk of atherosclerosis and cardiovascular disease. Although data on tracking of body mass index (BMI) are available, little is known about the impact of weight change over time on the development of vascular damage.

OBJECTIVE

To evaluate the relationship between adolescent BMI as well as change in BMI from adolescence into young adulthood and cardiovascular risk, as estimated by common carotid intima-media thickness (CIMT).

DESIGN

Cohort study.

SUBJECTS

A total of 750 healthy young adults, aged 27-30 y, who attended secondary school in Utrecht, the Netherlands.

MEASUREMENTS

Data on adolescent weight, height, blood pressure and puberty stage were available from the original school health records of the Municipal Health Service. At young adulthood, a questionnaire on cardiovascular risk factors was completed and fasting blood sample was drawn and common CIMT was measured.

RESULTS

One standard deviation (s.d.) increase in adolescent BMI was associated with 2.3 microm [95% confidence interval (CI): 1.3; 3.3] increase in mean common CIMT in young adults after adjustment for gender, adolescent age, adolescent blood pressure, puberty stage and lumen diameter. Further adjustment for adult cardiovascular risk factors did not change the relationship (linear regression coefficient=2.1 microm/s.d.; 95% CI: 1.0; 3.1). Adjustment for adult BMI attenuated the association (linear regression coefficient=0.9 microm/s.d.; 95% CI: -0.3; 2.2) as the majority of overweight and obese adolescents remained overweight or became obese young adults. Subjects who remained in the upper BMI distribution from adolescence into young adulthood had a significantly higher common CIMT compared to those who showed relative weight loss over time (mean difference 14.7 mum; P<0.001). These latter showed similar CIMT values as individuals with constant low BMI.

CONCLUSION

Adolescent BMI predicts cardiovascular risk, as estimated by common CIMT in young adulthood. Individuals who experience the largest increase in BMI and those who remain overweight over time have the thickest common CIMT.

Insulin resistance induces hyperleptinemia, cardiac contractile dysfunction but not cardiac leptin resistance in ventricular myocytes

Insulin resistance is a metabolic syndrome commonly seen in obesity. Leptin, the obese gene product, plays a role in the regulation of cardiac function. Elevated leptin levels have been demonstrated under insulin-resistant states such as obesity and hypertension, although their role in cardiac dysfunction is unknown. This study was designed to determine the impact of prediabetic insulin resistance on leptin levels and leptin-induced cardiac contractile response. Whole-body insulin resistance was generated with a 10-week dietary sucrose feeding. Contractile and intracellular Ca(2+) properties were evaluated in ventricular myocytes using an IonOptix system. The contractile indices analyzed included peak shortening (PS), time-to-PS (TPS), time-to-90% relengthening (TR(90)), maximal velocity of shortening/relengthening (+/-dL/dt), fura-fluorescence intensity change (deltaFFI) and decay rate (tau). Sucrose-fed rats displayed significantly elevated body weight and plasma leptin levels, depressed PS, +/-dL/dt, shortened TPS, prolonged TR(90) and tau, as well as reduced deltaFFI compared to the starch-fed control group. Leptin (1-1000 nM) elicited a concentration-dependent depression of PS and deltaFFI in myocytes from both starch and sucrose groups. Leptin-induced contractile depression was abolished by the nitric oxide synthase inhibitor Nomega-nitro-L-arginine methyle ester, elevation of the extracellular Ca(2+) concentration, the Janus activated kinase 2 inhibitor AG-490 or the mitogen activated protein kinase inhibitor SB203580 in myocytes from both sucrose and starch groups. Moreover, AG-490 and SB203580 unmasked a positive response of PS in myocytes from both groups. These data indicate that insulin resistance directly induces hyperleptinemia and cardiac contractile dysfunction, without affecting leptin-mediated cardiac contractile function at the myocyte level.

Prevalence and awareness of diabetes and mean fasting glucose by age, sex, and region: results from the Nutrition and Health Survey in Taiwan, 1993-1996

AIMS

The objective of this study was to evaluate the prevalence and awareness of diabetes mellitus (DM) in Taiwan.

METHODS

The Nutrition and Health Survey in Taiwan for people aged > or = 4 years was conducted between 1993 and 1996, using a multistaged, stratified, and clustered sampling scheme.

RESULTS

The prevalence of DM, defined by fasting whole blood glucose > or = 6.1 mmol/l or diagnosed DM subjects taking hypoglycaemic drugs, was 3.7% in men > or = 19 years and 6.3% in women. Corresponding to age groups 19-44, 45-64 and > or = 65 years, the prevalence was 1.5%, 7.9% and 7.8% in men and 0.5%, 12.3% and 19.6% in women, respectively. People in mountainous areas and in Peng-Hu islands had the highest prevalence, but the lowest awareness rates among seven survey strata (regions). Women from metropolitan cities had the lowest DM prevalence and body mass index (BMI) values, but the highest rate of DM awareness among all strata. This phenomenon was not apparent in men. The age, sex, and regional patterns of DM prevalence were consistent with those of BMI.

CONCLUSIONS

The prevalence of DM in Taiwan in 1993-1996 was relatively high, given a mean BMI of 23 kg/m2 in adults. Gender and regional differences were apparent in DM prevalence and awareness and in mean BMI.

Diabetes and cardiovascular diseases

Diabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetic people have cardiovascular disease (CVD) risk factors comparable to those of nondiabetics who have had a myocardial infarction or stroke. Physiologic changes in diabetic hypertensive people include endothelial dysfunction, altered platelet activity, and microalbuminuria, all of which may increase coronary heart disease risk. Hyperglycemia and dyslipidemia have been shown to effect physiologic changes in the vasculature; therefore, establishing normoglycemia, reducing cholesterol levels, and controlling blood pressure are the primary and initial goals in the management of diabetic hypertensive patients. The atherosclerotic risk is greatest in poorly controlled patients, possibly because of associated hypercholesterolemia and hypertriglyceridemia. Aggressive management of risk factors such as hypertension, dyslipidemia, and platelet dysfunction in diabetics has been shown to reduce morbidity and mortality in prospective randomized controlled clinical trials. In this article we review the impact of diabetes mellitus on cardiovascular morbidity and mortality.

Endothelin-1 inhibits resistin secretion in 3T3-L1 adipocytes

Resistin is an adipocyte-derived hormone whose role in the development of insulin resistance is controversial. Endothelin-1 (ET-1) is a 21 amino acid peptide demonstrated to possess vasoconstrictor, positive inotropic, mitogenic, and metabolic properties. In numerous disease states, including congestive heart failure, obesity, and diabetes, elevated levels of ET-1 have been reported and are thought to contribute to the pathology of the disease. A recent study demonstrated that ET-1 induces the expression and stimulates the secretion of the adipose tissue-derived hormone leptin. However, the effect of ET-1 on resistin secretion has not been determined. To characterize the effect of ET-1 on resistin secretion, 3T3-L1 fibroblasts were differentiated into adipocytes and allowed to mature for 14 days. Cells were incubated for 24h with ET-1 (1-100 nM), insulin (1-100 nM), insulin+ET-1 (100 nM I+E) or the appropriate vehicle or antagonist. At the end of the incubation period, resistin secretion was determined in the media by immunoblotting and densitometric analysis. ET-1 (1-100 nM) significantly decreased basal resistin secretion by 49% (1 nM), 43% (10nM), and 59% (100 nM). Insulin (1-100 nM) produced a concentration-dependent increase in resistin secretion from 3T3-L1 adipocytes (1 nM-42%, 10nM-55%, and 100 nM-86% vs. control). Insulin-stimulated resistin secretion (100 nM) was almost completely inhibited (94%) by ET-1 (100 nM). The effects of ET-1 on resistin protein secretion were inhibited by co-incubation with the ET(A) receptor antagonist BQ-610. In conclusion, our studies demonstrate that basal and hormonal stimulation of resistin secretion by insulin are inhibited by ET-1. Such findings demonstrate that resistin secretion is regulated in a similar manner to other adipose tissue factors, including leptin, in 3T3-L1 adipocytes. In addition, our findings suggest that vascular factors such as ET-1 may regulate whole body energy metabolism through adipocyte-derived hormones, including leptin and resistin.

Cardiovascular risk factors in diabetic patients with hypertension

Individuals with diabetes mellitus have cardiovascular disease (CVD) mortality comparable to nondiabetics who have suffered a myocardial infarction or stroke. Aggressive management of risk factors such as hypertension, dyslipidemia, and platelet dysfunction in persons with diabetes has been shown to reduce morbidity and mortality in prospective randomized controlled clinical trials. Accordingly, there are national mandates to lower blood pressure to less than 130/85 mm Hg, reduce low-density lipoprotein cholesterol to less than 100 mg/dL, and institute aspirin therapy in adult patients with diabetes. Although not definitively shown to reduce CVD, there are also recommendations to control the level of glycemia, as well. This article discusses CVD risk factors in the diabetic patient with hypertension.

The use of ACE inhibitors on diabetic patients without renal disease

Strategies that interrupt the renin-angiotensin system, especially with angiotensin-converting enzyme (ACE) inhibition, reduce cardiovascular disease mortality and morbidity in high-risk persons such as those with the insulin resistance syndrome and diabetes mellitus. In the 1980s emphasis was placed on the renal protective effects of ACE inhibitors in patients with diabetes and proteinuria. During the past several years controlled clinical trials have demonstrated that ACE inhibition reduces cardiovascular disease (CVD) mortality and morbidity. This is especially important in patients in the United States, where 80% of excess mortality for diabetes mellitus is attributed to CVD. This article reviews the clinical trials in high-risk patients, especially those with diabetes, that shown beneficial CVD risk reduction with ACE inhibitors.

Abrogated leptin-induced cardiac contractile response in ventricular myocytes under spontaneous hypertension: role of Jak/STAT pathway

Leptin regulates cardiovascular function. Leptin levels are elevated in obesity and hypertension and may play a role in cardiovascular dysfunctions in these comorbidities. This study was designed to determine the influence of hypertension on the cardiac contractile response of leptin. Mechanical and intracellular Ca(2+) properties were evaluated using an IonOptix system in ventricular myocytes from spontaneously hypertensive (SHR) and age-matched Wistar Kyoto (WKY) rats. The contractile properties included peak shortening (PS), duration and maximal velocity of shortening/relengthening (TPS/TR(90), +/-dL/dt), and fura-fluorescence intensity change (DeltaFFI). NO and nitric oxide synthase (NOS) activity were assessed by the Griess and the (3)H-arginine/citrulline conversion assays, respectively. The leptin receptor (Ob-R) and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway were evaluated by Western blot analysis. SHR animals displayed significantly elevated blood pressure and plasma leptin levels. Leptin elicited a concentration-dependent inhibition of PS and DeltaFFI in WKY, but not in SHR myocytes. Leptin did not affect TPS, TR(90), or +/- dL/dt. The difference in leptin-induced contractile response between the WKY and the SHR groups was abolished by the NOS inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME), but not by elevated extracellular Ca(2+). Either the JAK2 inhibitor AG-490 or the mitogen-activated protein (MAP) kinase inhibitor SB203580 abrogated the leptin-induced response in the WKY myocytes, whereas AG-490 unmasked a negative response in PS in the SHR myocytes. SHR myocytes displayed similar Ob-R protein abundance and basal NO levels, a blunted leptin-induced increase in NOS activity as well as enhanced basal STAT3 levels compared with the WKY group. These data indicate that the leptin-induced cardiac contractile response is abolished by spontaneous hypertension, possibly because of mechanisms involving altered JAK/STAT, MAP kinase signaling, and NO response.