Hyperinsulinemia. A link between hypertension obesity and glucose intolerance

Nutraceutical approaches to metabolic syndrome

Metabolic Syndrome (MetS), affecting at least 30% of adults in the Western World, is characterized by three out of five variables, from high triglycerides, to elevated waist circumference and blood pressure. MetS is not characterized by elevated cholesterolemia, but is rather the consequence of a complex interaction of factors generally leading to increased insulin resistance. Drug treatments are of difficult handling, whereas well-characterized nutraceuticals may offer an effective alternative. Among these, functional foods, e.g. plant proteins, have been shown to improve insulin resistance and reduce triglyceride secretion. Pro- and pre-biotics, that are able to modify intestinal microbiome, reduce absorption of specific nutrients and improve the metabolic handling of energy-rich foods. Finally, specific nutraceuticals have proven to be of benefit, in particular, red-yeast rice, berberine, curcumin as well as vitamin D. All these can improve lipid handling by the liver as well as ameliorate insulin resistance. While lifestyle approaches, such as with the Mediterranean diet, may prove to be too complex for the single patient, better knowledge of selected nutraceuticals and more appropriate formulations leading to improved bioavailability will certainly widen the use of these agents, already in large use for the management of these very frequent patient groups. Key messages Functional foods, e.g. plant proteins, improve insulin resistance. Pro- and pre-biotics improve the metabolic handling of energy-rich foods. Nutraceutical can offer a significant help in handling MetS patients being part of lifestyle recommendations.

CART neurons in the arcuate nucleus and lateral hypothalamic area exert differential controls on energy homeostasis

OBJECTIVE

The cocaine- and amphetamine-regulated transcript (CART) codes for a pivotal neuropeptide important in the control of appetite and energy homeostasis. However, limited understanding exists for the defined effector sites underlying CART function, as discrepant effects of central CART administration have been reported.

METHODS

By combining Cart-cre knock-in mice with a Cart adeno-associated viral vector designed using the flip-excision switch (AAV-FLEX) technology, specific reintroduction or overexpression of CART selectively in CART neurons in the arcuate nucleus (Arc) and lateral hypothalamic area (LHA), respectively, was achieved. The effects on energy homeostasis control were investigated.

RESULTS

Here we show that CART neuron-specific reintroduction of CART into the Arc and LHA leads to distinct effects on energy homeostasis control. Specifically, CART reintroduction into the Arc of otherwise CART-deficient Cart^cre/cre mice markedly decreased fat mass and body weight, whereas CART reintroduction into the LHA caused significant fat mass gain and lean mass loss, but overall unaltered body weight. The reduced adiposity in Arc^CART;Cart^cre/cre mice was associated with an increase in both energy expenditure and physical activity, along with significantly decreased Npy mRNA levels in the Arc but with no change in food consumption. Distinctively, the elevated fat mass in LHA^CART;Cart^cre/cre mice was accompanied by diminished insulin responsiveness and glucose tolerance, greater spontaneous food intake, and reduced energy expenditure, which is consistent with the observed decrease of brown adipose tissue temperature. This is also in line with significantly reduced tyrosine hydroxylase (Th) and notably increased corticotropin-releasing hormone (Crh) mRNA expressions in the paraventricular nucleus (PVN).

CONCLUSIONS

Taken together, these results identify catabolic and anabolic effects of CART in the Arc and LHA, respectively, demonstrating for the first time the distinct and region-specific functions of CART in controlling feeding and energy homeostasis.

Metabolic inflexibility in individuals with obesity assessed by near-infrared spectroscopy

OBJECTIVE

To non-invasively evaluate differences in oxidative metabolism in individuals with obesity compared to normal weight using the near-infrared spectroscopy and vascular occlusion technique during hyperglycaemia.

METHODS

In all, 16 normal-weight individuals (body mass index: 21.3 ± 1.7 kg/m²) and 13 individuals with obesity (body mass index: 34.4 ± 2.0 kg/m²) had five vascular occlusion tests (pre, 30, 60, 90 and 120 min after glucose ingestion). Oxygen utilization was estimated from the area under the curve of the deoxyhemoglobin [HHb] signal during occlusion. Muscle reperfusion was derived from the area above the curve after cuff release.

RESULTS

The deoxyhemoglobin area under the curve during occlusion of the normal-weight individuals increased from 15,732 ± 2344 (% . s) at pre to 18,930 ± 3226 (% . s) ( p < 0.05) at 90 min after glucose ingestion. The deoxyhemoglobin area under the curve during occlusion decreased significantly from 14,695 ± 3341 (% . s) at pre to 11,273 ± 1825 (% . s) ( p < 0.05) and 11,360 ± 1750 (% . s) ( p < 0.05) at 30 and 60 min, respectively, after glucose ingestion. The area above the curve of deoxyhemoglobin during reperfusion decreased significantly from 6450 ± 765 (% . s) at pre to 4830 ± 963 (% . s) ( p < 0.05) at 60 min and to 4210 ± 595 (% . s) ( p < 0.01) at 90 min in normal-weight individuals after glucose ingestion, with no changes observed in individuals with obesity.

CONCLUSION

This study confirmed in vivo and non-invasively the metabolic inflexibility of skeletal muscle in individuals with obesity during hyperglycaemia.

GPR88 is a critical regulator of feeding and body composition in mice

GPR88 is an orphan G-protein-coupled receptor with predominant expression in reward-related areas in the brain. While the lack of GPR88 has been demonstrated to induce behavioral deficits, the potential function of the receptor in the control of food intake and energy balance remains unexplored. In this work, the role of GPR88 in energy homeostasis was investigated in Gpr88^−/− mice fed either standard chow or high fat diet (HFD). Gpr88^−/− mice showed significantly reduced adiposity accompanied with suppressed spontaneous food intake, particularly pronounced under HFD treatment. While energy expenditure was likewise lower in Gpr88^−/− mice, body weight gain remained unchanged. Furthermore, deregulation in glucose tolerance and insulin responsiveness in response to HFD was attenuated in Gpr88^−/− mice. On the molecular level, distinct changes in the hypothalamic mRNA levels of cocaine-and amphetamine-regulated transcript (Cartpt), a neuropeptide involved in the control of feeding and reward, were observed in Gpr88^−/− mice. In addition, GPR88 deficiency was associated with altered expressions of the anorectic Pomc and the orexigenic Npy in the arcuate nucleus, especially under HFD condition. Together, our results indicate that GPR88 signalling is not only important for reward processes, but also plays a role in the central regulatory circuits for energy homeostasis.

Differential Metabolic Effects of Beta-Blockers: an Updated Systematic Review of Nebivolol

Blood pressure management in hypertensive patients with metabolic abnormalities is challenging, since many of the antihypertensive drugs adversely affect metabolism. Besides effective control of blood pressure in patients with hypertension, third-generation beta-blockers such as nebivolol offer additional benefits for central hemodynamics and neutral or beneficial effects on metabolism. Emerging clinical data suggest that nebivolol also has similar effects on metabolism in obese hypertensive and hypertensive diabetic patients. The present article will provide a systematic analysis of the pathophysiological links among hypertension, insulin resistance, and metabolic syndrome. We will also summarize the available clinical evidence regarding the metabolic effects of beta-blockers in hypertensive patients, with an emphasis on nebivolol. Nebivolol exerts neutral or beneficial effects on insulin sensitivity and lipid metabolism in hypertensive patients, owing to its nitric oxide-mediated vasodilatory and antioxidative properties. Thus, nebivolol could be a favorable therapeutic option for the treatment of hypertension in patients with impaired glucose and lipid metabolism.

The prevalence of impaired fasting glucose and undiagnosed diabetes mellitus and associated risk factors among adults living in a rural Koladiba town, northwest Ethiopia

Background

Diabetes mellitus is becoming a big public health challenge, particularly in developing countries like Ethiopia. It is a manageable disease if early screening and follow up is made. However, as studies in Ethiopia are limited and unorganized, determining the magnitude of prediabetes and diabetes and identifying associated risk factors is quite essential.

Methods

A community-based, cross-sectional study was conducted from February to April 2015 among adults (aged ≥20 years) in a rural Koladiba town. A multistage sampling technique was used to select a total of 392 study participants. Data were collected after a fully informed written consent was obtained from each participant. Demographic, behavioral, and clinical data were collected using a well-structured questionnaire. Multivariable logistic regression models were fitted to control the effect of confounders. Adjusted odds ratios (AOR) with their 95% confidence intervals (95% CI) were computed to measure associations. A p value of <0.05 was considered as statistically significant.

Results

The prevalence of impaired fasting glucose and undiagnosed diabetes mellitus were 12% (95% CI 9–16) and 2.3% (95% CI 1.1–4), respectively, in Koladiba. Overweight (AOR: 4.257, 95% CI 1.345–13.476), obesity (AOR: 5.26, 95% CI 1.138–24.316), hypertriglyceridemia (AOR: 2.83, 95% CI 1.451–5.521), and systolic hypertension (AOR: 3.858, 95% CI 1.62–9.189) were found to be independently associated with impaired fasting glucose. Positive family history of diabetes also showed a marginal association with impaired fasting glucose (p = 0.057). Male sex (p = 0.012) and hypertriglyceridemia (p = 0.030) were associated with undiagnosed diabetes mellitus.

Conclusions

The prevalence of impaired fasting glucose and undiagnosed diabetes mellitus are found to be significant. Obesity, hypertriglyceridemia, and systolic hypertension are independently associated with impaired fasting glucose among adults. We recommend that the community be aware of healthy life style, early screening, and maintain continuous follow up.

Impaired fasting glucose predicts the development of hypertension over 6years in female adults: Results from the rural Chinese cohort study

AIMS

To investigate whether impaired fasting glucose (IFG) is an independent risk factor for incident hypertension in a rural Chinese population.

METHODS

We selected 9583 eligible participants 18 to 75years old, who were without hypertension and diabetes at baseline (from 2007 to 2008) and were from a rural area in the middle of China. Concentration of fasting glucose at baseline was assessed in quartiles to predict hypertension risk by gender. Odds ratios (ORs) and 95% confidence intervals (CIs) for IFG (fasting glucose of 100 to 125mg/dl) associated with hypertension were estimated by logistic regression models.

RESULTS

Risk of hypertension was increased for females with glucose levels in quartile 2 (90-96mg/dl), quartile 3 (96-102mg/dl), and quartile 4 (102-125mg/dl) versus quartile 1 (<90mg/dl): OR=1.27 (95% CI=1.01-1.60), 1.30 (1.04-1.63), and 1.55 (1.24-1.93), respectively. During the 6-year follow-up, the cumulative incidence of hypertension was greater for people with IFG than normal fasting glucose (NFG) at baseline (23.9% vs 18.4%, p<0.001 for males and 23.8% vs 16.4%, p<0.001 for females). Risk of incident hypertension was significantly increased for females with IFG versus NFG (OR=1.23 95% CI=1.05-1.45).

CONCLUSIONS

IFG may be an independent risk factor for hypertension in normotensive nondiabetic Chinese females.

Glycemic, insulinemic and incretin responses after oral trehalose ingestion in healthy subjects

Background

Trehalose is hydrolyzed by a specific intestinal brush-border disaccharidase (trehalase) into two glucose molecules. In animal studies, trehalose has been shown to prevent adipocyte hypertrophy and mitigate insulin resistance in mice fed a high-fat diet. Recently, we found that trehalose improved glucose tolerance in human subjects. However, the underlying metabolic responses after trehalose ingestion in humans are not well understood. Therefore, we examined the glycemic, insulinemic and incretin responses after trehalose ingestion in healthy Japanese volunteers.

Methods

In a crossover study, 20 fasted healthy volunteers consumed 25 g trehalose or glucose in 100 mL water. Blood samples were taken frequently over the following 3 h, and blood glucose, insulin, active gastric inhibitory polypeptide (GIP) and active glucagon-like peptide-1 (GLP-1) levels were measured.

Results

Trehalose ingestion did not evoke rapid increases in blood glucose levels, and had a lower stimulatory potency of insulin and active GIP secretion compared with glucose ingestion. Conversely, active GLP-1 showed higher levels from 45 to 180 min after trehalose ingestion as compared with glucose ingestion. Specifically, active GIP secretion, which induces fat accumulation, was markedly lower after trehalose ingestion.

Conclusions

Our findings indicate that trehalose may be a useful saccharide for good health because of properties that do not stimulate rapid increases in blood glucose and excessive secretion of insulin and GIP promoting fat accumulation.

Sphingolipid regulators of cellular dysfunction in Type 2 diabetes mellitus: a systems overview

Climbing obesity rates have contributed to worldwide increases in obesity-associated diseases, including the metabolic syndrome and Type 2 diabetes mellitus (T2DM). Sphingolipids, an important class of structural and signaling lipids, have emerged as key players in the development and pathogenesis of insulin resistance and T2DM. More specifically, sphingolipids have been demonstrated to play integral roles in lipotoxicity and other aspects of pathogenesis in T2DM, although the cellular mechanisms by which this occurs and by which sphingolipid metabolism is dysregulated in T2DM remain under investigation. This review summarizes current knowledge of sphingolipid metabolism and signaling in key organs and tissues affected by T2DM, including the pancreas, adipose tissue, skeletal muscle, cardiovascular system and liver, and highlights areas that ripe for future investigation.

Effects of a Novel Glucokinase Activator, HMS5552, on Glucose Metabolism in a Rat Model of Type 2 Diabetes Mellitus

Glucokinase (GK) plays a critical role in the control of whole-body glucose homeostasis. We investigated the possible effects of a novel glucokinase activator (GKA), HMS5552, to the GK in rats with type 2 diabetes mellitus (T2DM). Male Sprague-Dawley (SD) rats were divided into four groups: control group, diabetic group, low-dose (10 mg/kg) HMS5552-treated diabetic group (HMS-L), and high-dose (30 mg/kg) HMS5552-treated diabetic group (HMS-H). HMS5552 was administered intragastrically to the T2DM rats for one month. The levels of total cholesterol, triglyceride, fasting plasma insulin (FINS), and glucagon (FG) were determined, and an oral glucose tolerance test was performed. The expression patterns of proteins and genes associated with insulin resistance and GK activity were assayed. Compared with diabetic rats, the FINS level was significantly decreased in the HMS5552-treated diabetic rats. HMS5552 treatment significantly lowered the blood glucose levels and improved GK activity and insulin resistance. The immunohistochemistry, western blot, and semiquantitative RT-PCR results further demonstrated the effects of HMS5552 on the liver and pancreas. Our data suggest that the novel GKA, HMS5552, exerts antidiabetic effects on the liver and pancreas by improving GK activity and insulin resistance, which holds promise as a novel drug for the treatment of T2DM patients.

Insulin resistance: potential role of the endogenous nitric oxide synthase inhibitor ADMA

The insulin resistance syndrome (IRS) is considered to be a new target of risk-reduction therapy. The IRS is a cluster of closely associated and interdependent abnormalities and clinical outcomes that occur more commonly in insulin-resistant/hyperinsulinemic individuals. This syndrome predisposes individuals to type 2 diabetes, cardiovascular diseases, essential hypertension, certain forms of cancer, polycystic ovary syndrome, nonalcoholic fatty liver disease, and sleep apnea. In patients at high risk for cardiovascular diseases, endothelial dysfunction is observed in morphologically intact vessels even before the onset of clinically manifest vascular disease. Indeed, there are several lines of evidence that indicate that endothelial function is compromised in situations where there is reduced sensitivity to endogenous insulin. It is well established that a decreased bioavailability of nitric oxide (NO) contributes to endothelial dysfunction. Furthermore, NO may modulate insulin sensitivity. Activation of NO synthase (NOS) augments blood flow to insulin-sensitive tissues (i.e. skeletal muscle, liver, adipose tissue), and its activity is impaired in insulin resistance. Inhibition of NOS reduces the microvascular delivery of nutrients and blunts insulin-stimulated glucose uptake in skeletal muscle. Furthermore, induction of hypertension by administration of the NOS inhibitor NG-monomethyl-L-arginine is also associated with insulin resistance in rats. Increased levels of asymmetric dimethylarginine (ADMA) are associated with endothelial vasodilator dysfunction and increased risk of cardiovascular diseases. An intriguing relationship exists between insulin resistance and ADMA. Plasma levels of ADMA are positively correlated with insulin resistance in nondiabetic, normotensive people. New basic research insights that provide possible mechanisms underlying the development of insulin resistance in the setting of impaired NO bioavailability will be discussed.

The Hypertension of Hemophilia Is Not Explained by the Usual Cardiovascular Risk Factors: Results of a Cohort Study

Background. The etiology of the high prevalence of hypertension among patients with hemophilia (PWH) remains unknown. Methods. We compared 469 PWH in the United States with males from the National Health and Nutrition Examination Survey (NHANES) to determine whether differences in cardiovascular risk factors can account for the hypertension in hemophilia. Results. Median systolic and diastolic BP were higher in PWH than NHANES (P < 0.001) for subjects not taking antihypertensives. Those taking antihypertensives showed similar differences. Differences in both systolic and diastolic BP were especially marked among adults <30 years old. Differences between PWH and NHANES persisted after adjusting for age and risk factors (body mass index, renal function, cholesterol, smoking, diabetes, Hepatitis C, and race). Conclusions. Systolic and diastolic BP are higher in PWH than in the general male population and especially among PWH < 30 years old. The usual cardiovascular risk factors do not account for the etiology of the higher prevalence of hypertension in hemophilia. New investigations into the missing link between hemophilia and hypertension should include age of onset of hypertension and hemophilia-specific morbidities such as the role of inflammatory joint disease.

Blood pressure in Warmblood horses before and during a euglycemic-hyperinsulinemic clamp

Background

Insulin resistance (IR) in humans is related to hypertension and impaired vasodilation. Insulin administration has been shown to lower blood pressure both in insulin resistant as well as in insulin sensitive individuals. The aim of the study was to investigate the association between insulin sensitivity and alterations in blood pressure in healthy horses before and after a euglycemic-hyperinsulinemic clamp (EHC). A 3-h EHC was performed in 13 healthy horses (11 mares, 2 geldings). Blood samples for measurement of plasma glucose and insulin were collected before the start of the EHC, every 10 min during the EHC and immediately after the EHC. Mean, systolic- and diastolic blood pressure was measured before and during the final 10 min of the EHC using an indirect high-definition oscillometric monitor (HDO, horse model) applied to the middle of the coccygeal artery. Five consecutive measurements were made in each horse and on each occasion. Insulin and glucose data from the EHC were used to calculate the mean rate of glucose disposal per unit of insulin during steady state (M/I ratio). Insulin resistance was defined as a M/I ratio <5 mg/kg/min/mUL (Lindåse et al. in Am J Vet Res 77:300–309, 2016).

Results

Insulin administration decreased systolic, diastolic and mean arterial pressure in all horses. The M/I ratio for all horses was negatively correlated with the decrease in systolic blood pressure (r² = 0.55, P = 0.004) and mean arterial pressure (r² = 0.31, P = 0.048) but not diastolic blood pressure (r² = 0.12, P = 0.26). Eight horses were defined as insulin resistant (IR) and five horses had normal insulin sensitivity. The five horses with normal insulin sensitivity showed a greater decrease in systolic blood pressure (−17.0 ± 7.4 vs. −3.4 ± 4.6 mmHg, P = 0.001) and MAP (19.2 ± 14.7 vs. 6.9 ± 8.7 mmHg, P = 0.04) than IR horses. There was no difference in the decrease in diastolic blood pressure between groups (16 ± 12.8 vs. 8.9 ± 12.1 mmHg, P = 0.17).

Conclusions

This study indicates that there is a relationship between insulin sensitivity and systolic and MAP in horses. However, studies on a larger number of horses are needed to confirm this association.

Calbindin-D9k Ablation Disrupt Glucose/Pancreatic Insulin Homeostasis

It has been proposed that cellular Ca²⁺ signals activate hormone secretion. In pancreatic β cells, which produce insulin, Ca²⁺ signals have been known to contribute to insulin secretion. Prior to this study, we confirmed that insulin-secreting β cells express CaBP-9k, and assumed that CaBP-9k play a role in β cell insulin synthesis or secretion. Using CaBP-9k knock out (KO) mice, we demonstrated that ablation of CaBP-9k causes reducing insulin secretion and increasing serum glucose. To compare the role of CaBP-9k with pathophysiological conditions, we exposed wild-type and CaBP-9k KO mice to hypoxic conditions for 10 days. Hypoxia induced endoplasmic reticulum (ER) stress, increasing both insulin signaling and insulin resistance. By exposing hypoxia, CaBP-9k KO mice showed an increased level of ER stress marker protein relative to wild type mice. Without hypoxic conditions, CaBP-9K ablation regulates calcium channels and causes ER stress in a CaBP-9K specific manner. Ablation of CaBP-9k also showed decreased levels of sulfonylurea receptor1 (SUR1) and inward-rectifier potassium ion channel 6.2 (K_ir6.2), which are insulin secretion marker genes. Overall, the results of the present study demonstrated that CaBP-9k regulates synthesis of insulin and is part of the insulin-secreting calcium signaling.

Possible Epidemiological Factors Associated with Rupture of the Posterior Tibial Tendon

Rupture of the posterior tibial tendon has been postulated to occur, in part, as a result of degenerative changes to the tendon. This possibility was examined by a review of 67 patients (average age 57 years) diagnosed with rupture of the posterior tibial tendon. Forty-five of the 67 patients (60%) had one or more of the following positive medical histories: (1) hypertension, (2) obesity, (3) diabetes mellitus, (4) previous surgery or trauma about the medial aspect of the foot, or (5) steroid exposure. Thirty-five patients (52%) had either hypertension, diabetes mellitus, or obesity. A statistical correlation was demonstrated between rupture of the posterior tibial tendon and obesity ( P = .005) and to a lesser extent hypertension ( P = .025). These disorders have been uniformly associated with an acceleration of the degenerative processes associated with aging, commonly via an acceleration of microvascular and macrovascular diseases. An additional vascular risk is implicated by the known zone of hypovascularity of the posterior tibial tendon and risk of rupture secondary to systemic or local injections of corticosteroids. The prevalence of posterior tibial tendon rupture parallels the degenerative processes of aging, hypertension, diabetes mellitus, and obesity. Additionally, the effects of corticosteroids and local surgical procedures may further be associated with local vascular impairment and eventual rupture.

Anti-obesity effects of boiled tuna extract in mice with obesity induced by a high-fat diet

The aim of this study was to examine the anti-obesity effects of boiled tuna extract in C57BL/6N mice with obesity induced by a high-fat diet (HFD). We determined the anti-obesity effects of boiled tuna extract (100, 200, or 400 mg/kg) on the progression of HFD-induced obesity for 10 weeks. The mice were divided into 5 groups as follows: the normal diet (ND) group (n=10); the HFD group (n=10); the mice fed HFD and 100 mg/kg boiled tuna extract group (n=10); those fed a HFD and 200 mg/kg boiled tuna extract group (n=10); and those fed a HFD and 400 mg/kg boiled tuna extract group (n=10). Changes in body weight, fat content, serum lipid levels and lipogenic enzyme levels were measured. The consumption of boiled tuna extract lowered epididymal tissue weight and exerted anti-obesity effects, as reflected by the serum glucose, triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL‑C), low-density lipoprotein cholesterol (LDL-C), insulin and leptin levels. In addition, we demonstrated changes in liver adipogenic- and lipogenic-related protein expression by western blot analysis. Boiled tuna extract downregulated the levels of the CCAAT/enhancer-binding protein α, β and δ (C/EBPα, β, δ), and peroxisome proliferator-activated receptor-γ (PPAR-γ) adipocyte marker genes. Boiled tuna extract also attenuated adipogenic and lipogenic gene expression, namely the levels of fatty acid synthase (FAS), lipoprotein lipase (LPL), acetyl-CoA carboxylase (ACC), glucose transporter type 4 (Glut4) and phosphorylated adenosine monophosphate-activated protein kinase α and β (AMPKα, β) in a dose-dependent manner. Moreover, the consumption of boiled tuna extract restored the levels of superoxide dismutase (SOD), catalase (CAT), glutamic oxaloacetic transaminase (GOT), glutamic-pyruvate transaminase (GPT), aspartate transaminase (AST) and alanine transaminase (ALT) to those of the control group. These results suggest that boiled tuna extract attenuates the progression of obesity by stimulating fatty acid oxidation through the upregulation of AMPK genes, as well as by inhibiting the synthesis of adipogenic and lipogenic enzymes. These characteristics of boiled tuna extract highlight its potential anti-obesity effects.

The joint association of self-rated health and diabetes status on 14-year mortality in elderly men and women

PURPOSE

Low self-rated health (SRH) has been found to be associated with increased risk of type 2 diabetes (T2D) and with mortality. We examined the possible interaction between SRH and diabetic state on all-cause mortality in a large cohort of elderly subjects, followed for 14 years.

METHODS

During the years 2000-2004, survivors of the nationwide longitudinal Israel Study of Glucose Intolerance, Obesity and Hypertension were interviewed and examined for the third follow-up. The 1037 participants (mean age 72.4 ± 7.2 years) were asked to rate their health as: excellent, good, fair, poor, or very poor. Glucose categories were as follows: Normoglycemic, Prediabetes, T2D and Undiagnosed diabetes. Survival time was defined as the time from interview to date of death or date of last vital status follow-up (August 1, 2013). Multivariate Cox proportional hazards models were performed in order to assess whether SRH interacts with glycemic state in the association with mortality.

RESULTS

A better SRH was reported by those with undiagnosed than known diabetes, and best for normoglycemic and prediabetic individuals. While all individuals with fair or poor/very poor SRH were at increased risk of mortality compared to those with excellent/good SRH, in the known diabetic individuals a greater hazard was observed in the excellent/good SRH (HR 3.32, 95 % CI 1.71-6.47) than in those with fair or poor/very poor SRH (HR 2.19, 95 % CI 1.25-3.86), after adjusting for age, sex, ethnic origin, marital status, education, BMI, physical activity, CVD, tumors, and creatinine level (p for interaction = 0.01).

CONCLUSIONS

Self-rated health is not a sensitive tool for predicting mortality in elderly men and women with known T2D.

Rubus crataegifolius Bunge regulates adipogenesis through Akt and inhibits high-fat diet-induced obesity in rats

Background

Obesity is one of the greatest public health problems and major risk factors for serious metabolic diseases and significantly increases the risk of premature death. The aim of this study was to determine the inhibitory effects of Rubus crataegifolius Bunge (RCB) on adipocyte differentiation in 3 T3-L1 cells and its anti-obesity properties in high fat diet (HFD)-induced obese rats.

Methods

3 T3-L1 adipocytes and HFD-induced obese rats were treated with RCB, and its effect on gene expression was analyzed using RT-PCR and Western blotting experiments.

Results

RCB treatment significantly inhibited adipocyte differentiation by suppressing the expression of C/EBPβ, C/EBPα, and PPARγ in the 3 T3-L1 adipocytes. Subsequently, the expression of the PPARγ target genes aP2 and fatty acid synthase (FAS) decreased following RCB treatment during adipocyte differentiation. In uncovering the specific mechanism that mediates the effects of RCB, we demonstrated that the insulin-stimulated phosphorylation of Akt strongly decreased and that its downstream substrate phospho-GSK3β was downregulated following RCB treatment in the 3 T3-L1 adipocytes. Moreover, LY294002, an inhibitor of Akt phosphorylation, exerted stronger inhibitory effects on RCB-mediated suppression of adipocyte differentiation, leading to the inhibition of adipocyte differentiation through the downregulation of Akt signaling. An HFD-induced obesity rat model was used to determine the inhibitory effects of RCB on obesity. Body weight gain and fat accumulation in adipose tissue were significantly reduced by the supplementation of RCB. Moreover, RCB treatment caused a significant decrease in adipocyte size, associated with a decrease in epididymal fat weight. The serum total cholesterol (TC) and triglyceride (TG) levels decreased in response to RCB treatment, whereas HDL cholesterol (HDL-C) increased, indicating that RCB attenuated lipid accumulation in adipose tissue in HFD-induced obese rats.

Conclusion

Our results demonstrate an inhibitory effect of RCB on adipogenesis through the reduction of the adipogenic factors PPARγ, C/EBPα, and phospho-Akt. RCB had a potent anti-obesity effect, reducing body weight gain in HFD-induced obese rats.

Electronic supplementary material

The online version of this article (doi:10.1186/s12986-016-0091-0) contains supplementary material, which is available to authorized users.

Hyperinsulinemia adversely affects lung structure and function

There is limited knowledge regarding the consequences of hyperinsulinemia on the lung. Given the increasing prevalence of obesity, insulin resistance, and epidemiological associations with asthma, this is a critical lacuna, more so with inhaled insulin on the horizon. Here, we demonstrate that insulin can adversely affect respiratory health. Insulin treatment (1 μg/ml) significantly (P < 0.05) increased the proliferation of primary human airway smooth muscle (ASM) cells and induced collagen release. Additionally, ASM cells showed a significant increase in calcium response and mitochondrial respiration upon insulin exposure. Mice administered intranasal insulin showed increased collagen deposition in the lungs as well as a significant increase in airway hyperresponsiveness. PI3K/Akt mediated activation of β-catenin, a positive regulator of epithelial-mesenchymal transition and fibrosis, was observed in the lungs of insulin-treated mice and lung cells. Our data suggests that hyperinsulinemia may have adverse effects on airway structure and function. Insulin-induced activation of β-catenin in lung tissue and the contractile effects on ASM cells may be causally related to the development of asthma-like phenotype.

Tacrolimus Induces Insulin Resistance and Increases the Glucose Absorption in the Jejunum: A Potential Mechanism of the Diabetogenic Effects

Background

The use of the immunosuppressive drug tacrolimus (TAC) is related to new onset diabetes after transplantation. Herein, we examined the effect of intraperitoneal administered TAC on intestinal glucose absorption in mice.

Methods

Animals received low, medium, or high dose TAC (0.5, 1, or 5 mg/kg/d, respectively), or 0.9% saline solution (control) for 14 days. Oral glucose tolerance test (OGTT), insulin concentration test, and serum TAC concentration measurements was performed after 14 days of TAC exposure. Plasma insulin was assessed and electrogenic glucose absorption were measured by the sodium-dependent increase of the short-circuit current. Expression levels of the glucose transporters sodium glucose co-transporter (SGLT) 1, glucose transporter (GLUT) 2, and GLUT5 were also determined.

Results

Oral glucose absorption assessed by OGTT was significantly enhanced in the low, medium, and high groups. Serum insulin was elevated in the medium and high group compared with the control. Moreover, glucose-induced Isc was significantly higher in TAC administrated groups, which indicates that SGLT1 activity increased. Transcription levels and protein abundance of SGLT1 in the experimental groups also increased compared with the control.

Conclusions

TAC induced insulin resistance and strengthened intestinal glucose absorption by increasing the activity and expression of the glucose transporter, SGLT1.

Higher glucose, insulin and insulin resistance (HOMA-IR) in childhood predict adverse cardiovascular risk in early adulthood: the Pune Children's Study

AIMS/HYPOTHESIS

The Pune Children's Study aimed to test whether glucose and insulin measurements in childhood predict cardiovascular risk factors in young adulthood.

METHODS

We followed up 357 participants (75% follow-up) at 21 years of age who had undergone detailed measurements at 8 years of age (glucose, insulin, HOMA-IR and other indices). Oral glucose tolerance, anthropometry, plasma lipids, BP, carotid intima-media thickness (IMT) and arterial pulse wave velocity (PWV) were measured at 21 years.

RESULTS

Higher fasting glucose, insulin and HOMA-IR at 8 years predicted higher glucose, insulin, HOMA-IR, BP, lipids and IMT at 21 years. A 1 SD change in 8 year variables was associated with a 0.10-0.27 SD change at 21 years independently of obesity/adiposity at 8 years of age. A greater rise in glucose-insulin variables between 8 and 21 years was associated with higher cardiovascular risk factors, including PWV. Participants whose HOMA-IR measurement remained in the highest quartile (n = 31) had a more adverse cardiovascular risk profile compared with those whose HOMA-IR measurement remained in the lowest quartile (n = 28).

CONCLUSIONS/INTERPRETATION

Prepubertal glucose-insulin metabolism is associated with adult cardiovascular risk and markers of atherosclerosis. Our results support interventions to improve glucose-insulin metabolism in childhood to reduce cardiovascular risk in later life.

High Blood Pressure and Its Association With Incident Diabetes Over 10 Years in the Korean Genome and Epidemiology Study (KoGES)

OBJECTIVE

No prospective, community-based cohort studies have investigated the association between blood pressure and diabetes in Asian ethnicity. We investigated this issue in a 10-year prospective, community-based study of Koreans.

RESEARCH DESIGN AND METHODS

We studied whether high blood pressure was associated with the development of diabetes in a population-based cohort, where we sampled ∼5,000 random subjects each from rural and urban areas (age range 40-69 years) during 2001-2010. Among 10,038 subjects, 8,359 without diabetes at baseline were categorized into normal (n = 4,809), prehypertension (n = 2,141), stage 1 hypertension (n = 804), and stage 2 hypertension (n = 605) groups, according to their blood pressure readings of <120/80 mmHg, 120-139/80-89 mmHg, 140-159/90-99 mmHg, and ≥160/100 mmHg, respectively. The development of diabetes was defined as a fasting glucose concentration of ≥126 mg/dL or a postload glucose concentration of ≥200 mg/dL, based on a 75-g oral glucose tolerance test, or the use of antidiabetic medication.

RESULTS

During the 10-year follow-up period, diabetes developed in 1,195 subjects (14.3%). The incidence of diabetes increased from 11.1% in the normal group to 17.0% in the prehypertension group, 17.7% in the stage 1 hypertension group, and 25.8% in the stage 2 hypertension group (P < 0.001). After adjusting for anthropometric factors; family history of diabetes; biochemical parameters including C-reactive protein, A1C, and fasting glucose and postload 2-h glucose levels; and the use of lipid-lowering medications, the hazard risks of diabetes development were 1.23 (95% CI 1.06-1.42), 1.26 (1.04-1.54), and 1.60 (1.30-1.96), respectively, in the prehypertension, stage 1 hypertension, and stage 2 hypertension groups.

CONCLUSIONS

Our findings indicate a grade association of baseline blood pressure with the development of diabetes in Korean individuals.

Diabetes in the Hispanic population

As the Hispanic population in the United States increases, more primary care physicians are being challenged to address the high incidence of diabetes and related metabolic disorders in Hispanic American patients. A variety of genetic, environmental, and socioeconomic factors contribute to this group's high susceptibility to diabetes. In this article, Drs Idrogo and Mazze discuss diagnosis of diabetes in Hispanic patients, as well as culturally sensitive screening and treatment strategies.

A Herbal Formula HT048, Citrus unshiu and Crataegus pinnatifida, Prevents Obesity by Inhibiting Adipogenesis and Lipogenesis in 3T3-L1 Preadipocytes and HFD-Induced Obese Rats

HT048 is a combination composed of Crataegus pinnatifida leaf and Citrus unshiu peel extracts. This study aimed to investigate potential anti-obesity effect of the combination. The 3T3-L1 adipocytes were treated with different doses of HT048 and triglyceride accumulation, glycerol release and adipogenesis-related genes were analyzed. For in vivo study, male Sprague Dawley rats were divided according to experimental diets: the chow diet group, the high-fat diet (HFD) group, the HFD supplemented with orlistat group, the HFD supplemented with HT048 group (0.2% or 0.4%) for 12 weeks. We measured the body weight, serum lipid levels and the expression of genes involved lipid metabolism. HT048 treatment dose-dependently suppressed adipocyte differentiation and stimulated glycerol release. The expressions of PPARγ and C/EBPα mRNA were decreased by HT048 treatment in adipocytes. HT048 supplementation significantly reduced the body and fat weights in vivo. Serum lipid levels were significantly lower in the HT048 supplemented groups than those of the HFD group. Expression of the hepatic lipogenesis-related genes were decreased and expression of the β-oxidation-related genes were increased in rats fed HT048 compared to that of animals fed HFD. These results suggest that HT048 has a potential benefit in preventing obesity through the inhibition of lipogenesis and adipogenesis.

Sense of coherence and 22-year all-cause mortality in adult men

BACKGROUND

Sense of coherence (SOC) is a central construct in Antonovsky's salutogenic theory, which focuses on people's health-promoting and health-protecting characteristics. We examined prospectively the association of SOC with all-cause mortality during 22 years (1989-2011).

METHODS

The data of 585 men from the Israel longitudinal study of Glucose Intolerance, Obesity, and Hypertension (The Israel GOH) comprised the analytic sample. Participants were 48-67 years old at study entry (1989). Information on sociodemographic, medical history and health-related risk factors were obtained at baseline through a face-to-face interview. Participants completed Antonovsky's 29-item SOC scale. Information on all-cause mortality was obtained from the Israeli Mortality Register (1989 through 2011). We evaluated the effect of SOC on time-to-death using multiple Cox proportional hazard regression.

RESULTS

Controlling for sociodemographic, smoking status and morbidities, there was strong evidence of an association between SOC and 22-year all-cause mortality [adjusted hazard ratio (aHR)=0.992, 95% CI 0.986-0.998 per unit]. Strong SOC was associated with a 35% reduction in all-cause mortality relative to weak SOC (aHR=0.653, 95% CI 0.454-0.939). There was no convincing evidence of a survival advantage for individuals with intermediate level of SOC relative to persons reporting weak SOC (aHR=0.821, 95% CI 0.595-1.134).

CONCLUSIONS

Our study provides strong evidence of an association between SOC and mortality, above and beyond potential confounding factors and established risk factors. Considerable more research is needed on the role of SOC in health and survival and the potential pathways linking SOC and health.

Systematic Analysis of Integrated Gene Functional Network of Four Chronic Stress-related Lifestyle Disorders

Background:

Stress is a term used to define factors involved in changes in the physiological balances resulting in disease conditions. Chronic exposure to stress conditions in modern lifestyles has resulted in a group of disorders called lifestyle disorders. Genetic background and environmental factors are interrelated to lifestyle in determining the health status of individuals. Hence, identification of disease-associated genes is the primary step toward explanations of pathogenesis of these diseases. In functional genomics, large-scale molecular and physiological data are used for the identification of causative genes associated with a disease.

Aim:

The objective of our study was to find a common set of genes involved in chronic stress-related lifestyle diseases such as cardiovascular diseases (CVDs), type 2 diabetes (T2D), hypertension (HTN), and obesity.

Materials and Methods:

In our study, we have performed a systematic analysis of the functional gene network of four chronic stress-related lifestyle diseases by retrieving genes from published databases. We have tried to systematically construct a functional protein-protein interaction (PPI) network. The goals of establishing this network were the functional enrichment study of interacting partners as well as functional disease ontology annotation (FunDO) of the enriched genes.

Results:

This study enabled the identification of key genes involved in these stress-related lifestyle diseases by prioritizing candidate genes based on their degree of involvement. In this systematic analysis, we have found key genes for these diseases based on their involvement and association at the gene network level and PPI.

Conclusion:

We have deciphered a group of genes that in combination play a crucial role and may impact the function of the whole genome in the four lifestyle disorders mentioned.

Obesity-related hypertension: possible pathophysiological mechanisms

Hypertension is one of the major risk factors of cardiovascular diseases, but despite a century of clinical and basic research, the discrete etiology of this disease is still not fully understood. The same is true for obesity, which is recognized as a major global epidemic health problem nowadays. Obesity is associated with an increasing prevalence of the metabolic syndrome, a cluster of risk factors including hypertension, abdominal obesity, dyslipidemia, and hyperglycemia. Epidemiological studies have shown that excess weight gain predicts future development of hypertension, and the relationship between BMI and blood pressure (BP) appears to be almost linear in different populations. There is no doubt that obesity-related hypertension is a multifactorial and polygenic trait, and multiple potential pathogenetic mechanisms probably contribute to the development of higher BP in obese humans. These include hyperinsulinemia, activation of the renin-angiotensin-aldosterone system, sympathetic nervous system stimulation, abnormal levels of certain adipokines such as leptin, or cytokines acting at the vascular endothelial level. Moreover, some genetic and epigenetic mechanisms are also in play. Although the full manifestation of both hypertension and obesity occurs predominantly in adulthood, their roots can be traced back to early ontogeny. The detailed knowledge of alterations occurring in the organism of experimental animals during particular critical periods (developmental windows) could help to solve this phenomenon in humans and might facilitate the age-specific prevention of human obesity-related hypertension. In addition, better understanding of particular pathophysiological mechanisms might be useful in so-called personalized medicine.

Endocrinology and Adolescence: aerobic exercise reduces insulin resistance markers in obese youth: a meta-analysis of randomized controlled trials

OBJECTIVE

The purpose of this meta-analysis was to examine the evidence for the effectiveness of aerobic exercise interventions on reducing insulin resistance markers in obese children and/or adolescents. A secondary outcome was change in percentage of body fat.

METHODS

A computerized search was made from seven databases: CINAHL, Cochrane Central Register of Controlled Trials, EMBASE, ERIC, MEDLINE, PsycINFO, and Science Citation Index. The analysis was restricted to randomized controlled trials that examined the effect of aerobic exercise on insulin resistance markers in obese youth. Two independent reviewers screened studies and extracted data. Effect sizes (ES) and 95% confidence interval (CI) were calculated, and the heterogeneity of the studies was estimated using Cochran's Q-statistic.

RESULTS

Nine studies were selected for meta-analysis as they fulfilled the inclusion criteria (n=367). Aerobic exercise interventions resulted in decreases in fasting glucose (ES=-0.39; low heterogeneity) and insulin (ES=-0.40; low heterogeneity) and in percentage of body fat (ES=-0.35; low heterogeneity). These improvements were specifically accentuated in adolescents (only in fasting insulin), or through programs lasting more than 12 weeks, three sessions per week, and over 60 min of aerobic exercise per session.

CONCLUSIONS

This meta-analysis provides insights into the effectiveness of aerobic exercise interventions on insulin resistance markers in the obese youth population.

Sympathetic activity and markers of cardiovascular risk in nondiabetic severely obese patients: the effect of the initial 10% weight loss

BACKGROUND

Obesity is associated with elevated cardiovascular mortality, which may be attributed, in part, to sympathetic nervous system (SNS) activation and an associated poor metabolic profile. We examined the effects of laparoscopic adjustable gastric band (LAGB) on SNS activity and cardiovascular profile when the initial weight loss of 10%, corresponding to the recommendation of clinical guidelines, was reached.

METHODS

Direct muscle sympathetic nerve activity (MSNA, microneurography), baroreflex function, and cardiovascular profile were examined before and after a predetermined weight loss of 10% in 23 severely obese nondiabetic individuals.

RESULTS

The 10% weight loss was achieved at an average of 7.3 ± 1.4 months (range = 1.3-23.3 months). This was associated with significant improvement in office systolic and diastolic blood pressure (BP) (-12 mm Hg and -5 mm Hg, respectively), a decrease in MSNA (33 ± 3 to 22 ± 3 bursts per minute), improvement in cardiac (16 ± 3 to 31 ± 4 ms/mm Hg) and sympathetic (-2.23 ± 0.39 to -4.30 ± 0.96 bursts/100 heartbeats/mm Hg) baroreflex function, total cholesterol (5.33 ± 0.13 to 4.97 ± 0.16 mmol/L), fasting insulin (29.3 ± 2.4 to 19.6 ± 1.1 mmol/L), and creatinine clearance (172 ± 11 to 142 ± 8 ml/min). None of the cardiovascular risk improvement related to the rate of weight loss. The change in systolic and diastolic BP correlated with change in waist circumference (r = 0.46, P = 0.04; r = 0.50, P = 0.02, respectively).

CONCLUSIONS

The initial 10% weight loss induced by LAGB was associated with substantial hemodynamic, metabolic, SNS, and renal function improvements. Changes in waist circumference appear to be an important factor contributing to BP adaptation after LAGB surgery.

Effect of orally administered L. fermentum NCIMB 5221 on markers of metabolic syndrome: an in vivo analysis using ZDF rats

Metabolic syndrome, encompassing type 2 diabetes mellitus and cardiovascular disease, is a growing health concern of industrialized countries. Ferulic acid (FA) is a phenolic acid found in foods normally consumed by humans that has demonstrated antioxidant activity, cholesterol-lowering capabilities, and anti-tumorigenic properties. Select probiotic bacteria, including Lactobacillus fermentum NCIMB 5221, produce FA due to intrinsic ferulic acid esterase activity. The aim of the present research was to investigate a FA-producing probiotic, L. fermentum NCIMB 5221, as a biotherapeutic for metabolic syndrome. The probiotic formulation was administered daily for 8 weeks to Zucker diabetic fatty (ZDF) rats, a model of hyperlipidemia and hyperglycemia. Results show that the probiotic formulation reduced fasting insulin levels and insulin resistance, significantly reduced serum triglycerides (p = 0.016), lowered serum low-density lipoprotein cholesterol levels (p = 0.008), and significantly reduced the atherogenic (p = 0.016) and atherosclerosis (p = 0.012) index as compared to the control animals. In addition, the probiotic formulation significantly increased high-density lipoprotein cholesterol levels (p = 0.041) as compared to the control animals. This research indicates that administration of the FA-producing L. fermentum NCIMB 5221 has the potential to reduce insulin resistance, hyperinsulinemia, hypercholesterolemia, and other markers involved in the pathogenesis of metabolic syndrome. Further studies are required to investigate the human clinical potential of the probiotic formulation in affecting the markers and pathogenesis of metabolic syndrome.

Partial deletion of eNOS gene causes hyperinsulinemic state, unbalance of cardiac insulin signaling pathways and coronary dysfunction independently of high fat diet

Abnormalities in eNOS gene, possibly interacting with high fat diet (HFD), affect peripheral vascular function and glucose metabolism. The relative role of eNOS gene, HFD and metabolic derangement on coronary function has not been fully elucidated. We test whether eNOS gene deficiency per se or in association with HFD modulates coronary function through mechanisms involving molecular pathways related to insulin signaling. Wild type (WT), eNOS^−/− and eNOS^+/− mice were studied. WT and eNOS^+/− mice were fed with either standard or HF diet for 16 weeks and compared with standard diet fed eNOS^−/−. Glucose and insulin tolerance tests were performed during the last week of diet. Coronary resistance (CR) was measured at baseline and during infusions of acetylcholine (Ach) or sodium-nitroprusside (SNP) to evaluate endothelium-dependent or independent vasodilation, in the Langendorff isolated hearts. Cardiac expression of Akt and ERK genes as evaluation of two major insulin-regulated signaling pathways involved in the control of vascular tone were assessed by western blot. HFD-fed mice developed an overt diabetic state. Conversely, chow-fed genetically modified mice (in particular eNOS^−/−) showed a metabolic pattern characterized by normoglycemia and hyperinsulinemia with a limited degree of insulin resistance. CR was significantly higher in animals with eNOS gene deletions than in WT, independently of diet. Percent decrease in CR, during Ach infusion, was significantly lower in both eNOS^−/− and eNOS^+/− mice than in WT, independently of diet. SNP reduced CR in all groups except eNOS^−/−. The cardiac ERK1-2/Akt ratio, increased in animals with eNOS gene deletions compared with WT, independently of diet. These results suggest that the eNOS genetic deficiency, associated or not with HFD, has a relevant effect on coronary vascular function, possibly mediated by increase in blood insulin levels and unbalance in insulin-dependent signaling in coronary vessels, consistent with a shift towards a vasoconstrictive pattern.

Coordinate control of adipose 'browning' and energy expenditure by β-adrenergic and natriuretic peptide signalling

The catecholamines and the adrenergic receptors have been long known to be vital components in the regulation of fat cell metabolism. Whether in response to stress, cold temperature or diet, the β-adrenergic receptors (βARs) respond to epinephrine/norepinephrine to activate a signalling cascade that drives triglyceride hydrolysis to free fatty acids for use as fuel for skeletal and cardiac muscle work. The βARs also are well-established activators of brown fat for the conversion of substrate energy to generate heat from the oxidation of glucose and fatty acids. Long thought to be irrelevant to the biology of adult humans, the realization that there is indeed functional brown fat in humans has now created great interest and enthusiasm over the possibility that recruiting brown fat to target obesity and metabolic disease could represent a viable therapeutic option. Coupled with newer evidence that various stimuli independent of the βARs may also be able to increase active brown adipocytes, including the cardiac natriuretic peptides, it is an exciting time to be working in this area. This review will focus on the catecholamines and natriuretic peptides as cooperative actors in promoting fat metabolism, and will consider areas in need of further research.

Evaluation of the Associations between Vascular Endothelial Function and Coronary Artery Stenosis in Patients with Elevated Blood Pressure during Coronary Angiography

<p><b>Objectives:</b> The aim of the present study is to explore the correlation between vascular endothelial function and coronary artery stenosis in non-hypertensive patients with elevated blood pressure under stress.</p><p><b>Methods:</b> This study included 1141 patients suspected of having coronary artery disease (CAD) without hypertension. Coronary arteriography and ultrasonic detection were used to measure the flow-mediated dilatation (FMD) function in the brachial artery. Patients were divided into 2 groups according to coronary angiography: experiment group, patients with blood pressure ? 140/90 mm Hg; control group, patients with blood pressure <140/90 mm Hg. The correlation between vascular endothelial function and coronary artery stenosis was observed.</p><p><b>Results:</b> The majority of the patients in the control group were found to have either normal coronary arteries or stenosis <50%. Patients in the experiment group (those with invasive blood pressure [IBP] >140/90) were more likely to have some degree of coronary artery stenosis. Specifically, there were significantly more patients with >50% stenosis in the experiment when compared with the control group (<i>P</i> < .05). The FMD in the experiment group was significantly lower than that in the control group (<i>P</i> < .05).</p><p><b>Conclusion:</b> The non-hypertensive patients with elevated blood pressure under stress had coronary artery stenosis, which was associated with vascular endothelial dysfunction.</p>

Hyperinsulinemic syndrome: the metabolic syndrome is broader than you think

BACKGROUND

Type 2 diabetes mellitus (T2DM) is characterized by hyperinsulinemia. In 2011 we showed that gastric bypass (RYGB) corrects these high levels even though insulin resistance remains high, ie, the operation "dissociates" hyperinsulinemia from insulin resistance. RYGB produces reversal of T2DM along with other diseases associated with the metabolic syndrome. This observation led us to examine whether these illnesses also were characterized by hyperinsulinemia.

METHODS

A systematic review was performed to determine whether hyperinsulinemia was present in disorders associated with the metabolic syndrome. We reviewed 423 publications. 58 were selected because of appropriate documentation of insulin measurements. Comparisons were based on whether the studies reported patients as having increased versus normal insulin levels for each metabolic disorder.

RESULTS

The presence (+) or absence (-) of hyperinsulinemia was documented in these articles as follows: central obesity (4+ vs 0-), diabetes (5+ vs 0-), hypertension (9+ vs 1-), dyslipidemia (2+ vs 0-), renal failure (4+ vs 0-), nonalcoholic fatty liver disease (5+ vs 0-), polycystic ovary syndrome (7+ vs 1-), sleep apnea (7+ vs 0-), certain cancers (4+ vs 1-), atherosclerosis (4+ vs 0-), and cardiovascular disease (8+ vs 0-). Four articles examined insulin levels in the metabolic syndrome as a whole (4+ vs 0-).

CONCLUSION

These data document that disorders linked to the metabolic syndrome are associated with high levels of insulin, suggesting that these diseases share a common etiology that is expressed by high levels of insulin. This leads us to propose the concept of a "hyperinsulinemic syndrome" and question the safety of insulin as a chronic therapy for patients with T2DM.

Renoprotective strategies in lupus nephritis: beyond immunosuppression

Lupus nephritis needs to be diagnosed promptly and treated specifically with appropriate immunosuppression. However, all patients with lupus nephritis have by definition chronic kidney disease (CKD) as they will have proteinuria with varying degrees of renal impairment. CKD requires careful additional management, not only to reduce the risk of progression to end-stage renal disease but also because it is probably the strongest risk for cardiovascular morbidity and mortality. This review focuses on the evidence underscoring strategies to prevent progression of CKD beyond the "simple" treatment of the lupus nephritis. The strategies include immaculate control of blood pressure, inhibition of the renin-angiotensin system to reduce blood pressure and proteinuria, and the benefits of lifestyle modifications such as tackling smoking, obesity and exercise. We also review the literature on control of dyslipidaemias which, although clearly of cardiovascular benefit, provide less compelling data for offering renoprotection. We touch on the emerging area of the importance of controlling urate levels in protecting against progressive renal impairment. Finally, there is a reminder about the importance of considering the nephrotoxicity of all medications prescribed for patients with lupus nephritis - above all the need to avoid the use of non-steroidal anti-inflammatory drugs. Overall, the theme is that there is much more to the management of patients with lupus nephritis than "just" the nephritis - a multidisciplinary approach involving nephrologists as well as rheumatologists is more likely to provide the appropriate wider care required for all patients with lupus nephritis.

Risk of postprandial insulin resistance: the liver/vagus rapport

Ingestion of a meal is the greatest challenge faced by glucose homeostasis. The surge of nutrients has to be disposed quickly, as high concentrations in the bloodstream may have pathophysiological effects, and also properly, as misplaced reserves may induce problems in affected tissues. Thus, loss of the ability to adequately dispose of ingested nutrients can be expected to lead to glucose intolerance, and favor the development of pathologies. Achieving interplay of several organs is of upmost importance to maintain effectively postprandial glucose clearance, with the liver being responsible of orchestrating global glycemic control. This dogmatic role of the liver in postprandial insulin sensitivity is tightly associated with the vagus nerve. Herein, we uncover the behaviour of metabolic pathways determined by hepatic parasympathetic function status, in physiology and in pathophysiology. Likewise, the inquiry expands to address the impact of a modern lifestyle, especially one's feeding habits, on the hepatic parasympathetic nerve control of glucose metabolism.