The impacts of obesity on the cardiovascular and renal systems: cascade of events and therapeutic approaches

The crucial role of hypertension in determining latent classes of metabolic syndrome in northern Iran and predictive power of these classes in non-alcoholic fatty liver: a gender-based insight

Introduction

This study investigates the subclasses of metabolic syndrome (Mets) and their relationship with non-alcoholic fatty liver (NAFLD) and the probable predictive role of serum vitamin D and CRP levels.

Methods

This community-based, cross-sectional study was performed on adults in the framework of the Amol cohort prospective study (AmolCPS). Mets was defined as Adult Treatment Panel III criteria (ATP III) and ultrasound was used to diagnose NAFLD. Anthropometric and blood pressure measurements were conducted, and biochemical measurements were assessed after fasting. Data analysis included Latent class analysis, two-tailed χ2 statistics, one-way analysis of variance, and logistic regression using Mplus (version 7.4) and spss (version 26) softwares.

Results

The study involved 2308 participants, with a mean age of 43.17 ± 12.30 years. Mets prevalence was 25.64%, with three identified classes: Mets with Hypertension (HTN), Mets without HTN (Non-HTN), and Low Risk. Mets with HTN had a high probability of at least four components, particularly high SBP. Non-HTN had at least three high probable components, especially high TG and low HDL but not high SBP and DBP. The low-risk class had a low probability of all components except low HDL in women. Serum vitamin D and CRP levels did not significantly predict Mets classes in men, while CRP level significantly predicted the HTN class in women (OR:1.03, CI:1.004-1.067). Both HTN, and Non-HTN Mets classes significantly increased the odds of NAFLD compared to the low risk class, especially in women (HTN class OR: 4.20 vs 2.94; non-HTN class OR: 5.60 vs 3.12 in women and men respectively).

Conclusion

The latent class analysis in northern Iran identified three Mets classes: HTN, Non-HTN, and low-risk, with hypertension playing a crucial role in determining these classes. These classes were stronger predictors of NAFLD in women. Serum CRP and vitamin D levels did not emerge as significant predictors of the classes, except for serum CRP in the HTN class among women.

Cardiovascular-kidney-metabolic syndrome - An integrative review

The American Heart Association recently defined the complex interactions among the cardiovascular, renal, and metabolic systems as CKM syndrome. To promote better patient outcomes, having a more profound understanding of CKM pathophysiology and pursuing holistic preventative and therapy strategies is critical. Despite many gaps in understanding CKM syndrome, this study attempts to elucidate two of these gaps: the new emerging biomarkers for screening and the role of inflammation in its pathophysiology. For this review, an extensive search for specific terms was conducted in the following databases: PubMed, Scopus, Web of Science, and Google Scholar. Studies were first assessed by title, abstract, keywords, and selected for portfolio according to eligibility criteria, which led to 38 studies. They provided background information about CKM syndrome; data suggested that serum uric acid, leptin, aldosterone, bilirubin, soluble neprilysin, lipocalin-type-prostaglandin-D-synthase, and endocan could be valuable biomarkers for CKM screening; and finally, the inflammation role in CKM.

Advanced glycation end products and insulin resistance in diabetic nephropathy

Insulin resistance is a central hallmark that connects the metabolic syndrome and diabetes to the resultant formation of advanced glycation end products (AGEs), which further results in the complications of diabetes, including diabetic nephropathy. Several factors play an important role as an inducer to diabetic nephropathy, and AGEs elicit their harmful effects via interacting with the receptor for AGEs Receptor for AGEs, by induction of pro-inflammatory cytokines, oxidative stress, endoplasmic reticulum stress and fibrosis in the kidney tissues leading to the loss of renal function. Insulin resistance results in the activation of other alternate pathways governed by insulin, which results in the hypertrophy of the renal cells and tissue remodeling. Apart from the glucose uptake and disposal, insulin dependent PI3K and Akt also upregulate the expression of endothelial nitric oxide synthase, that results in increasing the bioavailability of nitric oxide in the vascular endothelium, which further results in tissue fibrosis. Considering the global prevalence of diabetic nephropathy, and the impact of protein glycation, various inhibitors and treatment avenues are being developed, to prevent the progression of diabetic complications. In this chapter, we discuss the role of glycation in insulin resistance and further its impact on the kidney.

A novel index, Chinese visceral adiposity index is closely associated with urinary albumin-creatinine ratio in Chinese community adults, especially in hypertensive or hyperglycemic population: Results from the REACTION study

BACKGROUND

The association between the Chinese Visceral Adiposity Index (CVAI) and urinary albumin to creatinine ratio (UACR) has not been illustrated. The current study aimed to investigate the association between CVAI and UACR and to compare the discriminative power of CVAI, triglyceride, body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) with UACR in the Chinese community population.

METHODS

This study included 34 732 participants from the REACTION (Risk Evaluation of cAncers in Chinese diabeTic Individuals) study. Binary logistic regression analyses were performed to detect the association between CVAI, triglyceride, BMI, WC, WHR and UACR.

RESULTS

Binary logistic regression analysis showed that, after adjusting for potential confounders, in women, CVAI (odds ratio [OR]:1.16, 95% confidence interval [CI]: 1.01-1.34) and triglyceride (OR: 1.18, 95% CI: 1.04-1.33) were associated with UACR, whereas BMI, WC, and WHR were not associated with UACR; in men, CVAI (OR: 1.24, 95% CI: 1.02-1.50), WC (OR: 1.21, 95% CI 1.00-1.48), and triglycerides (OR: 1.18, 95% CI 0.97-1.44) were associated with UACR, whereas BMI and WHR were not associated with UACR. Stratified analysis showed that the correlation between CVAI and UACR was stronger in the population with 5.6 ≤ fasting blood glucose (FBG) <7.0 or 7.8 ≤ post-load blood glucose (PBG) <11.1 mmol/L, FBG ≥7.0 or PBG ≥11.1, systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg.

CONCLUSIONS

In the Chinese general population, CVAI and UACR were significantly associated in both genders. At higher CVAI levels, the population with prediabetes, diabetes, and hypertension has a more significant association between CVAI and UACR.

SGLT2 inhibitors attenuate nephrin loss and enhance TGF-β1 secretion in type 2 diabetes patients with albuminuria: a randomized clinical trial

To evaluate the effect of SGLT2 inhibitor (SGLT2i) on albuminuria, nephrin (NPH) and transforming-growth-factor-beta₁ (TGF-β1) levels in urine and low-grade inflammation in type 2 diabetes (T2D) patients. A randomized, blank-controlled clinical trial included 68 T2D patients and 10 controls. Based on the urinary albumin-to-creatinine ratio (UACR), 68 diabetic patients were stratified into three levels, UACR < 30 mg/g, UACR ≧ 30 mg/g to ≦ 300 mg/g and UACR ˃ 300 mg/g, who were randomized (1:1:1) to receive SGLT2i treatment for 12 weeks. The concentrations of NPH and TGF-β1 in urine were measured as indications of podocyte injury and renal fibrosis. Low-grade inflammation was assessed by the levels of IL-6, TNFα and hsCRP. After 12 weeks of SGLT2i treatment, the levels of UACR and NPH decreased, UTGF-β1 increased in the T2D with microalbuminuria and macroalbuminuria groups, NPH (1.12 [0.59, 1.29] vs. 0.71 [0.41, 1.07] µg/ml, P = 0.022) and (1.29 [0.99, 1.96] vs. 0.93 [0.57, 1.31] µg/ml, P = 0.002), UTGF-β1 (4.88 ± 1.31 vs. 7.27 ± 1.21 pg/ml, P  < 0.001) and (4.30 ± 1.34 vs. 6.78 ± 2.59 pg/ml, P  < 0.001), respectively. The changes in NPH were positively correlated with the UACR and negatively correlated with UTGF-β1 in T2D with albuminuria. SGLT2i alleviate nephrin loss and enhance TGF-β1 excretion in urine in T2DM with albuminuria. The anti-albuminuric effect of SGLT2i could be attributed to mitigating podocyte apoptosis and attenuating renal fibrosis.

Trial registration This clinical trial was registered on 15/10/2019, in ClinicalTrials.gov, and the registry number is NCT04127084.

Development and Validation of an Insulin Resistance Model for a Population with Chronic Kidney Disease Using a Machine Learning Approach

Background: Chronic kidney disease (CKD) is a complex syndrome without a definitive treatment. For these patients, insulin resistance (IR) is associated with worse renal and patient outcomes. Until now, no predictive model using machine learning (ML) has been reported on IR in CKD patients. Methods: The CKD population studied was based on results from the National Health and Nutrition Examination Survey (NHANES) of the USA from 1999 to 2012. The homeostasis model assessment of IR (HOMA-IR) was used to assess insulin resistance. We began the model building process via the ML algorithm (random forest (RF), eXtreme Gradient Boosting (XGboost), logistic regression algorithms, and deep neural learning (DNN)). We compared different receiver operating characteristic (ROC) curves from different algorithms. Finally, we used SHAP values (SHapley Additive exPlanations) to explain how the different ML models worked. Results: In this study population, 71,916 participants were enrolled. Finally, we analyzed 1,229 of these participants. Their data were segregated into the IR group (HOMA IR > 3, n = 572) or non-IR group (HOMR IR ≤ 3, n = 657). In the validation group, RF had a higher accuracy (0.77), specificity (0.81), PPV (0.77), and NPV (0.77). In the test group, XGboost had a higher AUC of ROC (0.78). In addition, XGBoost also had a higher accuracy (0.7) and NPV (0.71). RF had a higher accuracy (0.7), specificity (0.78), and PPV (0.7). In the RF algorithm, the body mass index had a much larger impact on IR (0.1654), followed by triglyceride (0.0117), the daily calorie intake (0.0602), blood HDL value (0.0587), and age (0.0446). As for the SHAP value, in the RF algorithm, almost all features were well separated to show a positive or negative association with IR. Conclusion: This was the first study using ML to predict IR in patients with CKD. Our results showed that the RF algorithm had the best AUC of ROC and the best SHAP value differentiation. This was also the first study that included both macronutrients and micronutrients. We concluded that ML algorithms, particularly RF, can help determine risk factors and predict IR in patients with CKD.

An alternative method for personalized tourniquet pressure in total knee arthroplasty: a prospective randomized and controlled study

Tourniquet use always carries potential risks, which can range from mild transient functional impairments of thigh pain, skin blisters to severe permanent dysfunction of limb paralysis, nerve injuries or compartment syndrome. The ideal method for minimizing intraoperative tourniquet pressure (TP) for reducing postoperative complications remains controversial. In this prospective, randomized and controlled study, we reinvestigated an estimation formula for TP based on thigh circumferences and systolic blood pressure (SBP) with two traditional methods for TP determination in total knee arthroplasty (TKA): SBP plus 100 mmHg and a fixed value of 300 mmHg. TP values and postoperative thigh pain scores were compared among three groups. The intraoperative TP value of the formula-calculated group was lower than that of the traditional groups (14.7 mmHg, P = 0.3475 and 94.7 mmHg, P < 0.0001, respectively), while no differences of hemostatic effect at the surgical fields and wound complications were detected among groups. The thigh pain scores at the tourniquet site decreased gradually over time and the estimation group had the lowest scores at each timepoint after surgery. Estimation method for TP was easy and rapid, without relying on specific equipment. It could provide a practical low TP and comparable hemostatic effect in TKA using an inflating tourniquet.

The Effect and Prevalence of Comorbidities in Adolescents With CKD and Obesity

Adolescent obesity and CKD are both significant public health issues independently. When seen as comorbid conditions, they can cause deleterious health outcomes that put them on the fast track to necessitate dialysis or transplantation. This paper analyzes the effects of various biomarkers and comorbidities seen in the intersection of obesity and CKD in the adolescent population. We illustrate the estimated prevalence of these biomarkers and comorbidities through a review of the literature, available treatment, and obesity-related glomerulopathies. We found significant prevalence of the biomarkers, microalbuminuria (9.42% ± 9.31% and interquartile range [IQR] of 9.5%), hypertension (23.60% ± 22.5% and IQR of 9.5%), low high-density lipoprotein (14.34% ± 5.46% and IQR of 5%), hyperfiltration (3.12% ± 5.16% and IQR of 4%), and lower estimated glomerular filtration rate 4.59 ± 2.75 and IQR of 3%. Identification of prevalent biomarkers and their manifestations can serve to inform clinicians what to look for in daily setting and help elucidate the magnitude of this growing issue. Additionally, pertinent treatment options from pharmacotherapy to bariatric surgery are outlined to provide care providers with the full spectrum of treatment options for obesity in adolescent populations.

Combined antihypertensive effect of unripe Rubus coreanus Miq. and Dendropanax morbiferus H. Lév. Extracts in 1 kidney-1 clip hypertensive rats and spontaneously hypertensive rats

Background

We previously showed that enzymatically hydrolyzed Dendropanax morbiferus H. Lév. leaf (Hy-DP) and unripe Rubus coreanus Miq. (5-uRCK) extracts exhibit potent vasodilator effects on isolated aortic rings from rats partly through endothelium-dependent and endothelium-independent mechanisms. These two extracts have different mechanisms of action; however, their combined effect on antihypertensive activity has not been explored.

Methods

The present study aims to investigate the effect of a chronic optimized mixture (HDR-2, composed of Hy-DP and 5-uRCK in a 2:1 mass ratio) on vascular tension and blood pressure in two different hypertensive rat models.

Results

The results showed that HDR-2 concentration-dependently relaxed endothelium-intact and endothelium-denuded aortic rings precontracted with phenylephrine. Antihypertensive effects were assessed in vivo on a 1 kidney-1 clip (1 K-1C) rat model of hypertension and spontaneously hypertensive rats (SHRs). Acute HDR-2 treatment significantly decreased systolic blood pressure (SBP) 3 h posttreatment in both models. Chronic HDR-2 administration also significantly decreased SBP in the hypertensive rat models. Moreover, HDR-2 increased eNOS protein expression and phosphorylation levels in the aorta.

Conclusion

Chronic HDR-2 administration may effectively improve vascular function by decreasing plasma angiotensin-converting enzyme (ACE) activity and AngII levels. HDR-2 significantly improved acetylcholine (ACh)-induced aortic endothelium-dependent relaxation and affected sodium nitroprusside (SNP)-induced endothelium-independent relaxation in SHRs.

Inhibition of HDACs (Histone Deacetylases) Ameliorates High-Fat Diet-Induced Hypertension Through Restoration of the MsrA (Methionine Sulfoxide Reductase A)/Hydrogen Sulfide Axis

[Figure: see text].

Comparison of visceral, body fat indices and anthropometric measures in relation to chronic kidney disease among Chinese adults from a large scale cross-sectional study

Background

The aim of the study was to assess the association between chronic kidney disease (CKD) and obesity in predicting CKD among Chinese adults, distinguishing between 5 different adiposity indices: visceral fat index (VFI), percentage body fat (PBF), body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR).

Methods

A total of 29,516 participants aged 35 years or above were selected using a stratified multistage random sampling method across China during 2012–2015. CKD was defined as an estimated glomerular filtration (eGFR) < 60 ml/min/1.72m².

Results

The overall weighted prevalence of CKD was 3.94% (3.62% in males and 4.25% in females). All five adiposity indices had significant negative correlations to eGFR (P < 0.05). The area under the ROC (receiver operating characteristic) curves (AUC) for PBF was almost significantly larger than the other adiposity indices (P < 0.001). In addition, PBF yielded the highest Youden index in identifying CKD (male: 0.15; female: 0.20). In the logistic analysis, PBF had the highest crude odds ratios (ORs) in both males (OR: 1.819, 95% CI 1.559–2.123) and females (OR: 2.268, 95% CI 1.980–2.597). After adjusted for age, smoking status, alcohol use, education level, marital status, rural vs. urban area, geographic regions, and diagnosis of hypertension, diabetes mellitus, myocardial infarction and stroke, the ORs on PBF remained significant for both genders (P < 0.05).

Conclusions

Obesity is associated with an increased risk of CKD. Furthermore, PBF was a better predictor for identifying CKD than other adiposity indices (BMI, WC, WHtR, and VFI).

Electronic supplementary material

The online version of this article (10.1186/s12882-018-0837-1) contains supplementary material, which is available to authorized users.

Interaction of Metabolic Health and Obesity on Subclinical Target Organ Damage

BACKGROUND

Metabolically healthy obese (MHO) individuals generally show better cardiovascular prognosis compared with metabolically unhealthy counterparts, which may be related to different patterns of target organ damage (TOD). We aimed to investigate the patterns of TOD related to obesity and metabolic unhealthiness.

METHODS

A total of 659 Korean adults (mean age, 60.0 ± 11.8 years; male, 51.1%) undergoing health examinations were stratified into four groups according to obesity (body mass index ≥25.0 kg/m²) and metabolic healthiness (meeting ≤1 criteria of metabolic syndrome excluding abdominal circumference): metabolically healthy nonobese (MHNO), metabolically unhealthy nonobese (MUNO), MHO, and metabolically unhealthy obese (MUO). Four measures of TOD were evaluated: arterial stiffness, renal dysfunction, left ventricular (LV) diastolic dysfunction, and LV hypertrophy (LVH).

RESULTS

In multivariable analyses, compared with the MHNO group, the MHO group showed 2.31 times higher odds for LVH, whereas, the MUNO group showed 3.14 and 6.28 times higher odds for increased arterial stiffness and renal dysfunction, respectively. Metabolic unhealthiness was associated with increased arterial stiffness [odds ratio (OR) 2.73; confidence interval (95% CI) 1.72-4.34], renal dysfunction (OR 4.02; 95% CI 1.54-10.49), and LV diastolic dysfunction (OR 2.28; 95% CI 1.14-4.55). Meanwhile, obesity showed weaker association with LVH and LV diastolic dysfunction, and was not associated with increased arterial stiffness and renal dysfunction in multivariable analyses.

CONCLUSIONS

Metabolic unhealthiness shows more association with TOD than obesity, which may contribute to the higher risk of cardiometabolic abnormalities in MUNO compared with MHO.

Improved In Vivo Efficacy of Anti-Hypertensive Biopeptides Encapsulated in Chitosan Nanoparticles Fabricated by Ionotropic Gelation on Spontaneously Hypertensive Rats

Recent biotechnological advances in the food industry have led to the enzymatic production of angiotensin I-converting enzyme (ACE)-inhibitory biopeptides with a strong blood pressure lowering effect from different food proteins. However, the safe oral administration of biopeptides is impeded by their enzymatic degradation due to gastrointestinal digestion. Consequently, nanoparticle (NP)-based delivery systems are used to overcome these gastrointestinal barriers to maintain the improved bioavailability and efficacy of the encapsulated biopeptides. In the present study, the ACE-inhibitory biopeptides were generated from stone fish (Actinopyga lecanora) protein using bromelain and stabilized by their encapsulation in chitosan (chit) nanoparticles (NPs). The nanoparticles were characterized for in vitro physicochemical properties and their antihypertensive effect was then evaluated on spontaneously hypertensive rats (SHRs). The results of a physicochemical characterization showed a small particle size of 162.70 nm, a polydispersity index (pdi) value of 0.28, a zeta potential of 48.78 mV, a high encapsulation efficiency of 75.36%, a high melting temperature of 146.78 °C and an in vitro sustained release of the biopeptides. The results of the in vivo efficacy indicated a dose-dependent blood pressure lowering effect of the biopeptide-loaded nanoparticles that was significantly higher (p < 0.05) compared with the un-encapsulated biopeptides. Moreover, the results of a morphological examination using transmission electron microscopy (TEM) demonstrated the nanoparticles as homogenous and spherical. Thus, the ACE-inhibitory biopeptides stabilized by chitosan nanoparticles can effectively reduce blood pressure for an extended period of time in hypertensive individuals.

Insulin Resistance in Kidney Disease: Is There a Distinct Role Separate from That of Diabetes or Obesity?

Insulin resistance is a central component of the metabolic dysregulation observed in obesity, which puts one at risk for the development of type 2 diabetes and complications related to diabetes such as chronic kidney disease. Insulin resistance and compensatory hyperinsulinemia place one at risk for other risk factors such as dyslipidemia, hypertension, and proteinuria, e.g., development of kidney disease. Our traditional view of insulin actions focuses on insulin-sensitive tissues such as skeletal muscle, liver, adipose tissue, and the pancreas. However, insulin also has distinct actions in kidney tissue that regulate growth, hypertrophy, as well as microcirculatory and fibrotic pathways which, in turn, impact glomerular filtration, including that governed by tubuloglomerular feedback. However, it is often difficult to discern the distinct effects of excess circulating insulin and impaired insulin actions, as exist in the insulin resistance individual, from the associated effects of obesity or elevated systolic blood pressure on the development and progression of kidney disease over time. Therefore, we review the experimental and clinical evidence for the distinct impact of insulin resistance on kidney function and disease.

Role of the histone deacetylase inhibitor valproic acid in high-fat diet-induced hypertension via inhibition of HDAC1/angiotensin II axis

BACKGROUND

Obesity is known as an epidemic worldwide because of consumption of westernized high-fat diets and one of the major risk factors of hypertension. Histone deacetylases (HDACs) control gene expression by regulating histone/non-histone protein deacetylation. HDAC inhibitors exert anti-cancer and anti-inflammatory effects and play a protective role in cardiovascular diseases. In the present study, we tested the effect of an FDA-approved pan-HDAC inhibitor valproic acid (VPA) on high-fat diet (HFD)-induced hypertension in mice. Furthermore, we examined the mechanism of VPA-induced prevention of hypertension.

METHODS

Nine-week-old male C57BL/6 mice were fed either a normal diet (ND) or HFD. When the HFD group reached a pre-hypertensive phase (130-140 mm Hg systolic blood pressure), VPA was administered for 6 days (300 mg kg^-1 per day). Body weights and blood pressure (BP), expression of renin-angiotensin system (RAS) components and HDAC1 were determined. The direct role of HDAC1 in the expression of RAS components was investigated using gene silencing.

RESULTS

HFD accelerated the increase in body weight from 22.4±1.3 to 31.9±3.0 compared to in the ND group from 22.7±0.9 to 26.0±1.7 (P=0.0134 ND vs HFD), systolic BP from 118.5±5.7 to 145.0±3.0 (P<0.001), and diastolic BP from 91.0±13.6 to 121.0±5.0 (P=0.006); BP was not altered in the ND group. HFD increased RAS components and HDAC1 in the kidneys as well as leptin in the plasma. VPA administration prevented the progression of hypertension and inhibited the increase in expression of HDAC1 and RAS components. VPA did not affect plasma leptin level. Knockdown of HDAC1 in MDCK cells decreased the expression of angiotensinogen and type 1 angiotensin II receptor.

CONCLUSIONS

VPA prevented HFD-induced hypertension by downregulating angiotensin II and its receptor via inhibition of HDAC1, offering a novel therapeutic option for HFD-induced hypertension.

High fat diet confers vascular hyper-contractility against angiotensin II through upregulation of MLCK and CPI-17

Obesity is a critical risk factor for the hypertension. Although angiotensin II (Ang II) in obese individuals is known to be upregulated in obesity-induced hypertension, direct evidence that explains the underlying mechanism for increased vascular tone and consequent increase in blood pressure (BP) is largely unknown. The purpose of this study is to investigate the novel mechanism underlying Ang II-induced hyper-contractility and hypertension in obese rats. Eight-week old male Sprague-Dawley rats were fed with 60% fat diet or normal diet for 4 months. Body weight, plasma lipid profile, plasma Ang II level, BP, Ang II-induced vascular contraction, and expression of regulatory proteins modulating vascular contraction with/without Ang II stimulation were measured. As a result, high fat diet (HFD) accelerated age-dependent body weight gaining along with increased plasma Ang II concentration. It also increased BP and Ang II-induced aortic contraction. Basal expression of p-CPI-17 and myosin light chain (MLC) kinase was increased by HFD along with increased phosphorylation of MLC. Ang II-induced phosphorylation of CPI-17 and MLC were also higher in HFD group than control group. In conclusion HFD-induced hypertension is through at least in part by increased vascular contractility via increased expression and activation of contractile proteins and subsequent MLC phosphorylation induced by increased Ang II.

Enhanced and Extended Anti-Hypertensive Effect of VP5 Nanoparticles

Hypertension has become a significant global public health concern and is also one of the most common risk factors of cardiovascular disease. Recent studies have shown the promising result of peptides inhibiting angiotensin converting enzyme (ACE) in lowering the blood pressure in both animal models and humans. However, the oral bioavailability and continuous antihypertensive effectiveness require further optimization. Novel nanoparticle-based drug delivery systems are helpful to overcome these barriers. Therefore, a poly-(lactic-co-glycolic) acid nanoparticle (PLGANPs) oral delivery system, of the antihypertensive small peptides Val-Leu-Pro-Val-Pro (VLPVP, VP5) model, was developed in this study and its antihypertensive effect was investigated in spontaneously hypertensive rats (SHRs) for the first time. The obtained VP5 nanoparticles (VP5-NPs) showed a small particle size of 223.7 ± 2.3 nm and high entrapment efficiency (EE%) of 87.37% ± 0.92%. Transmission electronic microscopy (TEM) analysis showed that the nanoparticles were spherical and homogeneous. The optimal preparation of VP5-NPs exhibited sustained release of VP5 in vitro and a 96 h long-term antihypertensive effect with enhanced efficacy in vivo. This study illustrated that PLGANPs might be an optimal formulation for oral delivery of antihypertensive small peptides and VP5-NPs might be worthy of further development and use as a potential therapeutic strategy for hypertension in the future.

The association between high-sensitivity C-reactive protein and hypertension in women of the CARDIA study

OBJECTIVE

The aim of this study was to determine the prevalence of hypertension in midlife women, characterize the association between high-sensitivity C-reactive protein (hs-CRP) and hypertension in women, and describe differences in hypertension prevalence by menopausal stage.

METHODS

We included 1,625 women, aged 43 to 55 years, with measurements of hs-CRP and detailed reproductive histories in the Coronary Artery Risk Development in Young Adults study at follow-up year 25. Prevalent hypertension was defined as a systolic blood pressure of 140 mm Hg, or diastolic blood pressure of 90 mm Hg or greater, or use of antihypertensive medications. Logistic regression was used for analysis.

RESULTS

The prevalence of hypertension was 25.8%, 37.8%, and 39.0% in premenopausal, perimenopausal, and postmenopausal women, respectively. The median (25th and 75th percentiles) of hs-CRP was 3.08 (1.12, 7.98) μg/mL and 1.18 (0.48, 3.15) μg/mL in women with and without hypertension, respectively. After adjusting for confounders, metabolic factors and body mass index, a doubling (100% increment) in hs-CRP levels was significantly associated with hypertension in premenopausal (1.27 [1.01-1.59]), but not in perimenopausal (1.12 [0.99-1.27]) or postmenopausal (1.09 [0.95-1.26]) women.

CONCLUSIONS

Hypertension was common in midlife women. The association of hs-CRP and hypertension was consistent across menopausal stages. The association of hs-CRP with hypertension was independent of body mass index in premenopausal but not in perimenopausal or postmenopausal women.

Effects of obesity and mild hypohydration on local sweating and cutaneous vascular responses during passive heat stress in females

The purpose of this study was to evaluate the effect of obesity and mild hypohydration on local sweating (LSR) and cutaneous vascular conductance (CVC) responses during passive heat stress in females. Thirteen obese (age, 24 ± 4 years; 45.4% ± 5.2% body fat) and 12 nonobese (age, 22 ± 2 years; 25.1% ± 3.9% body fat) females were passively heated (1.0 °C rectal temperature increase) while either euhydrated (EUHY) or mildly hypohydrated (HYPO; via fluid restriction). Chest and forearm LSR (ventilated capsule) and CVC (Laser Doppler flowmetry) onset, sensitivity, and plateau/steady state were recorded as mean body temperature increased (ΔTb). Participants began trials EUHY (urine specific gravity, Usg = 1.009 ± 0.006) or HYPO (Usg = 1.025 ± 0.004; p < 0.05), and remained EUHY or HYPO. Independent of obesity, HYPO decreased sweat sensitivity at the chest (HYPO = 0.79 ± 0.35, EUHY = 0.95 ± 0.39 Δmg·min(-1)·cm(-2)/°C ΔTb) and forearm (HYPO = 0.82 ± 0.39, EUHY = 1.06 ± 0.34 Δmg·min(-1)·cm(-2)/°C ΔTb); forearm LSR plateau was also decreased (HYPO = 0.66 ± 0.19, EUHY = 0.78 ± 0.23 mg·min(-1)·cm(-2); all p < 0.05). Overall, obese females had lower chest-sweat sensitivity (0.72 ± 0.35 vs. 1.01 ± 0.33 Δmg·min(-1)·cm(-2)/°C ΔTb) and plateau (0.55 ± 0.27 vs. 0.80 ± 0.25 mg·min(-1)·cm(-2); p < 0.05). While hypohydrated, obese females had a lower chest LSR (p < 0.05) versus nonobese females midway (0.45 ± 0.26 vs. 0.73 ± 0.23 mg·min(-1)·cm(-2)) and at the end (0.53 ± 0.27 vs. 0.81 ± 0.24 mg·min(-1)·cm(-2)) of heating. Furthermore, HYPO (relative to the EUHY trials) led to a greater decrease in CVC sensitivity in obese (-28 ± 27 Δ% maximal CVC/°C ΔTb) versus nonobese females (+9.2 ± 33 Δ% maximal CVC/°C ΔTb; p < 0.05). In conclusion, mild hypohydration impairs females' sweating responses during passive heat stress, and this effect is exacerbated when obese.

Elevated Serum Leptin Level Is Associated with Body Mass Index But Not with Serum C-reactive Protein and Erythrocyte Sedimentation Rate Values in Hemodialysis Patients

Objectives:

Aim of the present study was to investigate serum concentration of leptin and its association with values of body mass index (BMI), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) in hemodialysis (HD) patients.

Methods:

This cross-sectional study included 60 HD patients (34 male, 26 female) and 30 age- and sex-matched (4 males, 26 females) apparently healthy subjects. Serum leptin concentration was determined by an enzyme-linked immunosorbent assay (ELISA). Serum CRP concentration was measured by means of particle-enhanced immunonephelometry. ESR value was determined by Western Green method. BMI was calculated as weight (kg) divided by height squared (m²).

Results:

Results have shown that median serum leptin concentration (30.65 ng/mL; 12.48-86.40 ng/mL) was statistically significantly higher in HD patients compared to median serum leptin concentration (15.75 ng/mL; 9.15-30.65 ng/mL) in the control group of healthy subjects (p<0.05). Likewise, median serum CRP concentration (5.5 mg/L; 1.93-8.9 mg/L) and median ESR value (57.5 mm/h; 40.5-77.0 mm/h) were significantly higher in HD patients compared to median serum CRP concentration (0.8 mg/L; 0.38-1.43 mg/L) (p<0.001) and median ESR value (10.0 mm/h; 6.5-14.0 mm/h) (p<0.001) determined in the control group. Statistically significant positive correlation was found between BMI values and serum leptin concentration in HD patients (rho=0.434; p<0.001). Positive, although not significant, correlation was observed between serum CRP and leptin levels in HD patients (rho=0.171; p>0.05). Negative correlation between ESR values and serum leptin concentrations in HD patients was determined but it was not statistically significant (rho= -0.029; p>0.05).

Conclusions:

Increased serum concentration of leptin as pro-inflammatory cytokine as well as elevated serum values of CRP and ESR indicate presence of systemic micro inflammation in HD patients. Results of the present study point to possible use of serum leptin concentration as an indicator of nutritional status in HD patients based on observed significant positive correlation between serum leptin concentrations and BMI values. However, absence of significant association between serum leptin and CRP levels as well as between serum leptin concentrations and ESR values in HD patients requires further investigation and clarification.

Effect of weight reduction on the severity of lower urinary tract symptoms in obese male patients with benign prostatic hyperplasia: a randomized controlled trial

Purpose

We assessed whether weight reduction is an effective intervention for the management of lower urinary tract symptoms (LUTS) and investigated the relationship between obesity and LUTS.

Materials and Methods

This was a prospective randomized controlled trial that enrolled obese men older than 50 years with LUTS. The study period was 52 weeks. All patients received standardized alpha-adrenergic blocker therapy for the treatment of benign prostatic hyperplasia (BPH) during the run-in period. Patients were randomized to receive either a standardized prerecorded video program on the general principle of weight reduction or a comprehensive weight reduction program. Patients were assessed at different time points with symptom assessment, uroflowmetry, transrectal ultrasound, and metabolic assessment.

Results

Sixty-five patients were allocated to each study arm. After the study period, no significant difference in weight reduction was found between the two arms. When the pre- and postintervention parameters were compared, none were statistically different between the 2 arms, namely nocturia, International Prostate Symptom Score, quality of life assessment, and uroflowmetry parameters. When the whole study population was taken as a single cohort, these parameters were also not significantly different between the group with a body mass index of 25 to <30 kg/m² and the group with a BMI of 30 to 35 kg/m².

Conclusions

We found no association between obesity and LUTS. This could have been due to the less marked weight difference in our cohort. Whereas weight reduction may be an effective measure to improve LUTS, the implementation of a successful program remains a challenge.